Publikationen der letzten 7 Jahre

PubMed-Suche nach Gerhard Jahreis

2014

Jaudszus Anke, Lorkowski Stefan, Gruen Michael, Roth Alexander, Jahreis Gerhard (2014) Limited applicability of GW9662 to elucidate PPARγ-mediated fatty acid effects in primary human T-helper cells. Intern J Inflam, doi.org/10.1155/2014/149628
Synthetic antagonists of the nuclear receptor PPARγ such as GW9662 are widely used to elucidate receptor-mediated ligand effects. In addition and complementary to recent work, we examined whether GW9662 is suitable to serve for mechanistic investigation in T-helper cells. Human peripheral blood mononuclear cells (PBMC) were preincubated with increasing concentrations of GW9662 (0, 0.4, 2, and 10 μmol/L) 30 min before adding the c9,t11-isomer of conjugated linoleic acid (c9,t11-CLA) as representative of PPARγ-activating fatty acids with immunomodulatory properties. Corresponding cultures were incubated with GW9662 in the absence of the fatty acid. After 19 h, cells were mitogen stimulated for further 5 h. Subsequently, intracellular IL-2 was measured in CD3+CD4+ lymphocytes by means of flow cytometry. 100 μmol/L c9,t11-CLA reduced the number of T-helper cells expressing IL-2 by 68%. GW9662 failed to abrogate this fatty acid effect, likely due to the fact that the compound exerted an own inhibitory effect on IL-2 production. Moreover, GW9662 dose-dependently induced cell death in human leukocytes. These results suggest that application of GW9662 is not conducive in this experimental setting.

Bähr Melanie, Fechner Anita, Hasenkopf Katrin, Mittermaier Stephanie, Jahreis Gerhard (2014) Chemical composition of dehulled seeds of selected lupin cultivars in comparison to pea and soya bean. LWT - Food Science and Technology, in press
With the objective of promoting the cultivation, usage, and consumption of lupin, in the present study, the chemical and fibre composition of dehulled seeds of seven cultivars of different lupin species (Lupinus angustifolius, Lupinus albus and Lupinus luteus) was determined in comparison to pea (Pisum sativum) and soya bean (Glycine max). The mean protein content of lupin was significantly higher compared to pea (P < 0.001) and similar to soya bean, whereas the proportion of calculated carbohydrates was lowest for lupin (P < 0.001). The content of total dietary fibre and of calculated soluble fibre was higher for lupin compared to pea (P < 0.003) and soya bean (P < 0.013). In contrast to the existing literature, the soluble fibre content of lupin contributed about 75% of the total dietary fibre. In conclusion, dehulled lupin seeds can be considered as a valuable source of plant protein and dietary fibre, while simultaneously being low in carbohydrates. Therefore, lupin should be exploited more efficiently within human and also animal nutrition. In further studies, the impact of dehulling lupin seeds and of using different methodologies in fibre analyses on the results of chemical composition should be elucidated.

Kusche D, Kuhnt K, Ruebesam K, Rohrer C, Nierop AF, Jahreis G, Baars T (2014). Fatty acid profiles and antioxidants of organic and conventional milk from low- and high-input systems during outdoor period. J Sci Food Agric. Jun 5. doi: 10.1002/jsfa.6768. [Epub ahead of print]
Background: Intensification of organic dairy production leads to the question if the implementation of intensive feeding incorporating maize silage and concentrates was altering milk quality. Therefore the fatty acid (FA) profiles and antioxidants (AO) of milk on 24 farms divided in 4 system groups in 3 replications (n = 71) during outdoor period were analyzed. In this system comparison, a differentiation of the system groups and the effects of the main system factors 'intensification level' [high-input (HI) versus low-input (LI)] and 'origin' [organic (B) versus conventional (C)] were evaluated in a multivariate statistical approach.
Results: Consistent differentiation of milk from the system groups due to feeding related impacts was possible in general and on the basis of 15 markers. The prediction of the main system factors was based on 4-5 markers. The prediction of 'intensification level' was based mainly on CLA c9,t11 and C18:1 t11, whereas 'origin' on n-3 PUFA.
Conclusions: It was possible to demonstrate consistent differences in the FA and AO profiles of organic and standard conventional milk. Highest concentrations of nutritionally beneficial compounds were found in the low-input organic system (BLI). Adapted grass based feeding strategies including pasture offer the potential to produce a distinguishable organic milk product quality.

Mäkilä Leenamaija, Laaksonen Oskar, Diaz Jose Martin Ramos, Vahvaselkä Marjatta, Myllymäki Olavi, Lehtomäki Ilkka, Laakso Simo, Jahreis Gerhard, Jouppila Kirsi, Larmo Petra, Yang Baoru, Kallio Heikki (2014): Exploiting blackcurrant juice press residue in extruded snacks. LWT - Food Science and Technology 57, 618-627.
Extrusion process was developed to exploit blackcurrant juice press residues from industrial side-streams. Press residues obtained from conventional enzymatic pressing, with high content of fiber and seed oil, and novel non-enzymatic juice processing, with high content of sugars, fruit acids and anthocyanins, were extruded with barley fl our, oat fl our or oat bran. The recipes consisted of blackcurrant press residues (30%), cereal materials (40%) and potato starch (30%) and small amount of sugar and salt. When compared to enzymatic press residue and oat bran, the novel non-enzymatic press residue extruded with barley or oat fl our had higher expansion, lower hardness and density, higher redness (a*), lower pH, and higher contents of fructose, glucose and fruit acids, all contributing positively to liking of texture, appearance, and flavor as well as berry-like experience. These characteristics were obtained with more gentle processing parameters, consisting of a lower total mass flow, screw speed and barrel temperature. Female consumers gave lower ratings in flavor, appearance and overall pleasantness for blackcurrant snacks than males. The study presented a sustainable way of utilizing industrial press residues from different processes of berry juice pressing for production of healthy snacks and breakfast cereals.

Bähr Melanie, Fechner Anita, Kaatz Martin, Jahreis Gerhard: Skin prick test reactivity to lupin in comparison to peanut, pea, and soybean in atopic and non-atopic German subjects: A preliminary cross-sectional study. Immunity, Inflammation and Disease (2014) doi: 10.1002/iid3.24
The increasing use of lupin in food processing poses a problem of potential (cross-)allergic reactions. To evaluate the prevalence of sensitization to lupin in comparison to that of other legumes skin prick tests were performed with lupin, pea, peanut, and soybean in atopic (n=81) and non-atopic (n=102) German adults. Of these 183 subjects, 20 subjects had to be excluded due to invalid skin prick tests (reaction to histamine <3 mm or to sodium chloride >2 mm). Thus, skin prick tests of 163 subjects were included in final analyses. Of 163 subjects, 18 had a positive reaction to at least one legume tested. Overall skin prick test reactivity was different among non-atopic and atopic subjects (P=0.005). Altogether, six subjects (4%) were sensitized to lupin, 12 (7%) to pea, 5 (3%) to peanut, and 8 (5%) to soybean. Two (2%) of the 92 non-atopic subjects and 4 (6%) of the 71 atopic subjects had a positive skin prick test to lupin. Of the 6 subjects sensitized to lupin, 3 (50%) were also sensitized to pea, 3 (50%) to peanut, and 5 (83%) to soybean. In conclusion, the prevalence rates of lupin sensitization were comparable to or even lower than those of pea, peanut, and soybean. To date, lupin allergy is suspected to be relatively uncommon in the overall German population since lupin sensitization occurred in only 2% of non-atopic subjects. However, there is a clear risk of a lupin allergy in predisposed subjects, since the frequency of lupin sensitization was 6% in atopic subjects. In particular, subjects with existing sensitization or allergy to other legumes are at higher risk for a sensitization or allergy to lupin due to cross-reactivity.

Melanie Bähr, Anita Fechner Michael Kiehntopf, Gerhard Jahreis (2014). Consuming a mixed diet enriched with lupin protein beneficially affects plasma lipids in hypercholesterolemic subjects: A randomized controlled trial. Clinical Nutrition. http://dx.doi.org/10.1016/j.clnu.2014.03.008.
Background & aims: The objectives of this study were to assess whether 25 g/d lupin protein, integrated into a mixed diet, might affect cardiovascular risk factors and whether lL-arginine was responsible for these effects.
Methods: Seventy-two hypercholesterolemic subjects participated in the randomized, controlled, double-blind three-phase crossover study. They were assigned to three diets with 25 g/d lupin protein (LP), milk protein (MP) or milk protein plus 1.6 g/d arginine (MPA) each for 28 d in a random order interrupted by 6-week washout periods. Lupin protein and the comparator milk protein were incorporated into complex food products (bread, roll, sausage, and vegetarian spread). Arginine was administered via capsules. Sixty-eight subjects were included in final analyses.
Results: Compared with MP, LDL cholesterol was significantly lower after LP. Compared with MP and MPA, homocysteine was significantly lower after LP. Compared with baseline, concentrations of total, LDL, and HDL cholesterol significantly decreased after LP and MPA. Triacylglycerols and uric acid significantly decreased after LP. The relative changes in total and LDL cholesterol were significantly greater for subjects with severe hypercholesterolemia (>6.6 mmol/L) than those with moderate hypercholesterolemia (5.2–6.6 mmol/L).
Conclusions: The present study showed for the first time that incorporation of 25 g/d of lupin protein into a variety of complex food products lowers total and LDL cholesterol, triacylglycerols, homocysteine, and uric acid in hypercholesterolemic subjects. The hypocholesterolemic effect is stronger in subjects with severe hypercholesterolemia. Arginine might be responsible for some, but not all of the beneficial effects of lupin protein.

Katrin Kuhnt, Claudia Fuhrmann, Melanie Köhler, Michael Kiehntopf, Gerhard Jahreis. Dietary Echium oil increases long-chain n–3 PUFAs, including docosapentaenoic acid, in blood fractions and alters biochemical markers for cardiovascular disease independent of age, sex, and metabolic syndrome. J. Nutr. doi: 10.3945/jn.113.180802
Dietary supplementation with echium oil (EO) containing stearidonic acid (SDA) is a plant-based strategy to improve long-chain (LC) n-3 (ω-3) polyunsaturated fatty acid (PUFA) status in humans. We investigated the effect of EO on LC n-3 PUFA accumulation in blood and biochemical markers with respect to age, sex, and metabolic syndrome. This double-blind, parallel-arm, randomized controlled study started with a 2-wk run-in period, during which participants (n = 80) were administered 17 g/d run-in oil. Normal-weight individuals from 2 age groups (20-35 and 49-69 y) were allotted to EO or fish oil (FO; control) groups. During the 8-wk intervention, participants were administered either 17 g/d EO (2 g SDA; n = 59) or FO [1.9 g eicosapentaenoic acid (EPA); n = 19]. Overweight individuals with metabolic syndrome (n = 19) were recruited for EO treatment only. During the 10-wk study, the participants followed a dietary n-3 PUFA restriction, e.g., no fish. After the 8-wk EO treatment, increases in the LC n-3 metabolites EPA (168% and 79%) and docosapentaenoic acid [DPA (68% and 39%)] were observed, whereas docosahexaenoic acid (DHA) decreased (-5% and -23%) in plasma and peripheral blood mononuclear cells, respectively. Compared with FO, the efficacy of EO to increase EPA and DPA in blood was significantly lower (∼25% and ∼50%, respectively). A higher body mass index (BMI) was associated with lower relative and net increases in EPA and DPA. Compared with baseline, EO significantly reduced serum cholesterol, LDL cholesterol, oxidized LDL, and triglyceride (TG), but also HDL cholesterol, regardless of age and BMI. In the FO group, only TG decreased. Overall, daily intake of 15-20 g EO increased EPA and DPA in blood but had no influence on DHA. EO lowered cardiovascular risk markers, e.g., serum TG, which is particularly relevant for individuals with metabolic syndrome. Natural EO could be a noteworthy source of n-3 PUFA in human nutrition.

Anita Fechner, Michael Kiehntopf, Gerhard Jahreis (2014) The Formation of Short-Chain Fatty Acids Is Positively Associated with the Blood Lipid-Lowering Effect of Lupin Kernel Fiber in Moderately Hypercholesterolemic Adults. J. Nutr.
Lupin kernel fiber beneficially modifies blood lipids because of its bile acid–binding capacity. The aim of this study was to evaluate the preventive effects of a lupin kernel fiber preparation on cardiovascular diseases and to clarify possible mechanisms. In a randomized, double-blind, controlled crossover trial, 60 moderately hypercholesterolemic adults (plasma total cholesterol: >5.2 mmol/L) passed 3 intervention periods in different orders with a 2-wk washout phase between each. Participants consumed either a high-fiber diet containing 25-g/d lupin kernel fiber (LF) or citrus fiber (CF), or a low-fiber control diet (CD) for 4 wk each. Anthropometric, plasma, and fecal variables were assessed at baseline and after the interventions. Contrary to the CF period, total (9%) and LDL (12%) cholesterol as well as triacylglycerols (10%) were lower after the LF period when compared with the CD period [P # 0.02, adjusted for baseline, age, gender, and body mass index (BMI)]. HDL cholesterol remained unchanged. Moreover, the LF period reduced high-sensitivity C-reactive protein (P = 0.02) and systolic blood pressure (P = 0.01) when compared with baseline. Bile acid binding could not be shown because the excretion of total bile acids remained constant after the high-fiber diets. However, the LF period resulted in an enhanced formation of the main short-chain fatty acids in comparison with the CD period. During the CF period, only acetate increased significantly. Both highfiber diets led to higher satiety and modified nutritional behavior, resulting in significantly lower body weight, BMI, and waist circumference compared with the CD period. The blood lipid–lowering effects of LF are apparently not a result of bile acid binding. Rather, we hypothesize for the first time that the blood lipid–lowering effects of LF may be mainly attributed to the formation of short-chain fatty acids, specifically propionate and acetate.

Radtke Juliane, Geissler Stefanie, Schutkowski Alexandra, Brandsch Corinna, Kluge Holger, Duranti Marcello M, Keller Sylvia, Jahreis Gerhard, Hirche Frank, Stangl Gabriele I: Lupin protein isolate modifies cholesterol excretion and mRNA expression of intestinal sterol transporters in a pig model. Nutrition & Metabolism 2014, 11:9 doi:10.1186/1743-7075-11-9 versus casein.
Background Lupin proteins exert hypocholesterolemic effects in man and animals, although the underlying mechanism remains uncertain. Herein we investigated whether lupin proteins compared to casein modulate sterol excretion and mRNA expression of intestinal sterol transporters by use of pigs as an animal model with similar lipid metabolism as humans, and cellular cholesterol-uptake by Caco-2 cells.
Methods Two groups of pigs were fed cholesterol-containing diets with either 230 g/kg of lupin protein isolate from L. angustifolius or 230 g/kg casein, for 4 weeks. Faeces were collected quantitatively over a 5 d period for analysis of neutral sterols and bile acids by gas chromatographically methods. The mRNA abundances of intestinal lipid transporters were analysed by real-time RT-PCR. Cholesterol-uptake studies were performed with Caco-2 cells that were incubated with lupin conglutin gamma, phytate, ezetimibe or albumin in the presence of labelled [4-14C]-cholesterol.
Results Pigs fed the lupin protein isolate revealed lower cholesterol concentrations in total plasma, LDL and HDL than pigs fed casein (P < 0.05). Analysis of faeces revealed a higher output of cholesterol in pigs that were fed lupin protein isolate compared to pigs that received casein (+57.1%; P < 0.05). Relative mRNA concentrations of intestinal sterol transporters involved in cholesterol absorption (Niemann-Pick C1-like 1, scavenger receptor class B, type 1) were lower in pigs fed lupin protein isolate than in those who received casein (P < 0.05). In vitro data showed that phytate was capable of reducing the uptake of labelled [4-14C]-cholesterol into the Caco-2 cells to the same extend as ezetimibe when compared to control (-20.5% vs. -21.1%; P < 0.05).
Conclusions Data reveal that the cholesterol-lowering effect of lupin protein isolate is attributable to an increased faecal output of cholesterol and a reduced intestinal uptake of cholesterol. The findings indicate phytate as a possible biofunctional ingredient of lupin protein isolate.

González-Serrano AF, Ferreira CR, Pirro V, Heinzmann J, Hadeler KG, Herrmann D, Aldag P, Meyer U, Piechotta M, Rohrer C, Jahreis G, Dänicke S, Cooks RG, Niemann H. 2 specific Fatty Acid follow-up reveals rumen-protected fat supplementation effects on bovine oocyte quality and embryo development. Reprod Fertil Dev 26 (2014) 115-116. doi: 10.1071/RDv26n1Ab2
Information on how supplementation of high-yield dairy cows with rumen-protected fat affects fertility in cattle herds is scarce. Here, Holstein-Friesian heifers (n=84) received a supplement consisting of either rumen-protected conjugated linoleic acid (CLA; cis-9,trans-11-CLA and trans-10,cis-12-CLA) or stearic acid 18:0 (SA) on top of an isocaloric grass silage diet. Two supplementation doses were used (100 and 200 gd(-1)). Blood and follicular fluid were collected at the start and end of the supplementation period for analysis of cholesterol, insulin-like growth factor (IGF), and nonesterified fatty acids (NEFA), and for fatty acid profiling. Although cholesterol, IGF, and NEFA levels did not differ among experimental groups, lipid profiles in blood and follicular fluid were affected in a dose-dependent manner by both supplements. After 45 days of supplementation, oocytes were collected by ovum pick-up (OPU). The mRNA relative abundance of target genes (IGF1r, GJA1, FASN, SREBP1, and SCAP) was analysed in single in vitro- (24h IVM) and in vivo-matured (collected by OPU 20h after GnRH injection) oocytes and in vitro-produced blastocysts (Day 8) by qPCR (n=6/group). Lipid profiling of individual oocytes from the CLA-supplemented (n=37) and the SA-supplemented (n=50) was performed by desorption electrospray ionization mass spectrometry (DESI-MS). Oocytes from the CLA-supplemented (n=413) and the SA-supplemented (n=350) groups were used for assessing maturation and blastocysts development rates. In immature oocytes, CLA supplementation led to an increase of triacylglycerol 52:3 [TAG (52:3)] and TAG (52:2), squalene, palmitic acid 16:0, and oleic acid 18:1, and decreased abundance of TAG (56:3), TAG (50:2) and TAG (48:1). In vitro-matured oocytes showed different lipid profiles, with increased abundances of TAG (52:3), and TAG (52:2) as well as phosphatidylinositol 34:1 [Plo (34:1)], whereas phosphatidylglycerol (34:1) [PG (34:1)] and palmitic acid 16:0 were less abundant in in vitro-matured oocytes. SCAP was significantly down-regulated in in vitro-matured oocytes from supplemented heifers compared with their in vivo-matured counterparts. Maturation (CLA=74% v. SA=67%) and blastocyst rates (CLA=22.4% v. SA=12.7%) were different among experimental groups. One-way ANOVA and the Tukey-Kramer test were applied for a multiple comparison of means (P-value≤0.05 was considered as statistically significant). In conclusion, we demonstrate here that fatty acid monitoring along different compartments (i.e. blood system, follicular fluid, and intra-oocyte) after rumen-protected fat supplementation of dairy heifer diet reveals nutritional footprints on oocyte quality and embryo development. These results demonstrate the close relationship between nutrition and cattle herd's fertility and, at the same time, support the role of the bovine model for understanding nutritional-dependent fertility impairments.

Jaudszus Anke, Kramer Ronny, Pfeuffer Maria, Roth Alexander, Jahreis Gerhard, Kuhnt Katrin. trans Palmitoleic acid arises endogenously from dietary vaccenic acid. Am J Clin Nutr (2014) doi: 10.3945/ajcn.113.076117.
Background: trans Palmitoleic acid (t-16:1n–7, or 16:1t9 in the d nomenclature usually applied to trans fatty acids and used herein) arouses great scientific interest because it has been suggested to serve as a bio-marker for lower risks of type 2 diabetes and coronary artery disease. Objective: Although 16:1t9 has been assumed to derive from dietary sources, we examined the hypothesis that 16:1t9 might also be endogenously produced from its metabolic precursor vaccenic acid (t-18:1n–7 or 18:1t11).
Design: We reevaluated fatty acid data obtained from one human intervention study and one cellular model in both of which 18:1t11 was supplemented. Both studies have already been published, but to our knowledge, 16:1t9 has not yet been considered. This reanalysis of the datasets was reasonable because a new methodology for identifying 16:1 cis and trans isomers allowed us to address the subject presented in this article.
Results: Data showed that the systemic or intracellular increase in 16:1t9 was strongly correlated with the increase in 18:1t11 after the dietary intake or cellular uptake of 18:1t11. The conversion rate in humans was, on average, 17%. Conclusion: Our findings suggest that endogenous 16:1t9 is not, as has been assumed, exclusively diet derived but may also be produced by the partial beta-oxidation of dietary 18:1t11.

Trautvetter U, Jahreis G. Effect of supplementary calcium phosphate on plasma gastrointestinal hormones in a double-blind, placebo-controlled, cross-over human study. Br J Nutr 111 (2014) 287–293
Gastrointestinal hormones and Ca are associated with bone metabolism. The objective of the present human study was to determine the effect of calcium phosphate on the postprandial circulation of gastrointestinal hormones. A total of ten men participated in the present double-blind, placebo-controlled, cross-over study. The participants were divided into two groups. Of these, one group consumed bread enriched with 1 g Ca (pentacalcium hydroxy-triphosphate, CaP) daily for 3 weeks. The other group consumed placebo bread. After 2 weeks of washout, the intervention was changed between the groups for another 3 weeks. The subjects consumed a defined diet at the beginning (single administration) and at the end (repeated administration) of the intervention periods, and blood samples were drawn at 0, 30, 60, 120, 180 and 240 min. Between 0 and 30 min, the participants consumed a test meal, with or without CaP. The concentrations of gastrointestinal hormones (glucose-dependent insulinotropic polypeptide, glucagon-like peptide (GLP) 1 and GLP2), insulin and glucose were determined. The AUC of GLP1 (total and active) and GLP2 increased significantly after the repeated CaP administrations compared with that after placebo administration. The AUC of insulin and glucose showed no differences between the CaP and placebo administrations. CaP affects the postprandial plasma concentrations of gastrointestinal hormones through the modulation of the intestinal environment, e.g. bile acids and microbiota.

Toni Meier, Olaf Christen, Edmund Semler, Gerhard Jahreis, Lieske Voget-Kleschin, Alexander Schrode, Martina Artmann. Balancing virtual land imports by a shift in the diet. Using a land balance approach to assess the sustainability of food consumption. Germany as an example. Appetite 74 (2014) 20–34
Nutrition is considered as one of the main drivers of global environmental change. Dietary patterns in particular, embedded in the international trade of foods and other biomass based commodities, determine the dimension of beneficial or harmful environmental impacts of the agri-food sector – both domestically and abroad. In this study we analysed different dietary scenarios from a virtual land flow perspective, based on representative consumption data for Germany in the years 2006 and 1985–89. Further we identified the consumer groups that would have to adapt most to balance Germany’s virtual land import and analysed the impact reduced food wastage. For the study, official data sets concerning production, trade and consumption were used. We derived land use data from environmentally extended input–output data sets and FAO statistics. The conversion of agricultural raw products to consumed commodities is based on official processing and composition data. Subgroup-specific intake data from the last representative National Nutrition Survey in Germany were used. We analysed 42 commodities, aggregated into 23 product groups, seven land use types and six nutrition scenarios. The results show that in the baseline scenario the average nutrition in the year 2006 leads to a virtual land import of 707 m2 p_1 a_1, which represents 30% of the total nutrition-induced land demand of 2365 m2 p_1 a_1. On the other hand, the German agri-food sector exports virtual land, in the form of commodities, equivalent to 262 m2 p_1 a_1. In this paper we calculate that the resulting net import of virtual land could be balanced by way of a shift to an officially recommended diet and a reduction in the consumption of stimulants (cocoa, coffee, green/black tea, wine). A shift to an ovo-lacto-vegetarian or vegan diet would even lead to a positive virtual land balance (even with maintained consumption of stimulants). Moreover, we demonstrate that a shift in the average diet profile could lead to maintained or even expanded export competitiveness and simultaneously enable environmental benefits. Since such a diet shift complies with official dietary recommendations, it follows that public health benefits may well result. We show further that a reduction of avoidable food losses/wastage would not be sufficient to level out the virtual land balance of the average nutrition in Germany. Regarding the dietary developments in the last 20 years, we argue that a dietary shift resulting in a zero land balance is within reach. The population groups that would have to be addressed most are younger and middle-aged men. Nevertheless, women’s land saving potentials should not be ignored neither. Due to the fact that a western-style diet prevails in Germany, we argue that our basic findings are applicable to other industrialised and densely populated countries.

2013

Annemarie Grindel, Frank Staps, Katrin Kuhnt (2013) Cheek cell fatty acids reflect n-3 PUFA in bloodfractions during linseed oil supplementation: a controlled human intervention study. Lipids in Health and Disease 12:173¸ doi:10.1186/1476-511X-12-173.
Background: Adequate biomarkers for the dietary supply of fatty acids (FA) are FA of adipose tissue and blood fractions. In human studies, invasive sample collection is unpleasant for subjects. In contrast, cheek cell sampling can be considered as a non-invasive alternative to investigate FA status. The aim of this study was to analyze whether cheek cell FA composition reflect the supplementation of alpha-linolenic acid (ALA) using a linseed oil mixture compared to olive oil supplementation. Additionally, it was investigated if cheek cell FA composition correlates with the FA composition of plasma, red blood cells (RBC) and peripheral blood mononuclear cells (PBMC) before and during both interventions.
Methods: During a 10-week randomized, controlled, double-blind human intervention study, 38 subjects provided cheek cell and blood samples. After a two-week run-in period, the test group (n = 23) received 17 g/d of an ALA-rich linseed oil mixture, while the control group (n = 15) received 17 g/d of an omega-3 (n-3) polyunsaturated FA (PUFA)-free olive oil. Cheek cells and blood were collected on days 0, 7 and 56 of the 8-week intervention period. Results Compared to olive oil, the linseed oil intervention increased ALA and also the endogenously converted long-chain n-3 metabolites eicosatetraenoic-, icosapentaenoic- and docosapentaenoic acid in cheek cells (P ≤ 0.05). Docosahexaenoic acid remained unchanged. Reflecting the treatment, the n-6/n-3 ratio decreased in the test group. In general, cheek cell FA reflected the changes of FA in blood fractions. Independent of treatment, significant correlations (P ≤ 0.05) of n-6 PUFA and n-3 PUFA between cheek cells and plasma, RBC and PBMC were found, except for linoleic acid and ALA.
Conclusions: The changes in FA composition of cheek cells confirmed that ALA from linseed oil increased endogenously derived n-3 PUFA in cheek cell lipids. These changes in cheek cells and their correlation to the respective FA in blood fractions indicate the cheek cell FA profile as an adequate non-invasive biomarker for short-term n-3 PUFA intake and metabolism. Therefore, cheek cell FA can be used in human intervention studies or large-scale epidemiological studies, especially for assessment of the n-3 PUFA status.
Trial registration: ClinicalTrials.gov IDNCT01317290

Pfaender S, Heyden J, Friesland M, Ciesek S, Ejaz A, Steinmann J, Steinmann J, Malarski A, Stoiber H, Tsiavaliaris G, Bader W, Jahreis G, Pietschmann T, Steinmann E. (2013): Inactivation of Hepatitis C Virus Infectivity by Human Breast Milk. J Infect Dis. 208 (2013):1943-1952; doi: 10.1093/infdis/jit519.
Background. Hepatitis C virus (HCV) is spread through direct contact with blood, although alternative routes of transmission may contribute to the global burden. Perinatal infection occurs in up to 5% of HCV-infected mothers, and presence of HCV RNA in breast milk has been reported. We investigated the influence of breast milk on HCV infectiousness.
Methods/Results.Human breast milk reduced HCV infectivity in a dose-dependent manner. This effect was species-specific because milk from various animals did not inhibit HCV infection. Treatment of HCV with human breast milk did not compromise integrity of viral RNA or capsids but destroyed the lipid envelope. Fractionation of breast milk revealed that the antiviral activity is present in the cream fraction containing the fat. Proteolytic digestion of milk proteins had no influence on its antiviral activity, whereas prolonged storage at 4°C increased antiviral activity. Notably, pretreatment with a lipase inhibitor ablated the antiviral activity and specific free fatty acids of breast milk were antiviral.
Conclusions.The antiviral activity of breast milk is linked to endogenous lipase-dependent generation of free fatty acids, which destroy the viral lipid envelope. Therefore, nursing by HCV-positive mothers is unlikely to play a major role in vertical transmission.

Anna Eisenstadt, Ulrich Schäfer, Michael Glei, Gerhard Jahreis (2013) Iron metabolism and prevention of iron deficiency via iron fortification of foods Trace Elements and Electrolytes 30, 156-166
Introduction: Nutritional iron deficiency can be caused by low dietary iron bioavailability. The provision of foods fortified with iron might be a feasible strategy against nutritional iron deficiency in areas where its prevalence is high. However, the selection of an optimal combination of a food vehicle and an iron fortificant is challenging. The iron fortificant should be sufficiently bioavailable and should not adversely affect sensory properties of the fortified food.
Methods: Literature research was performed to identify such combinations from 22 efficacy and effectiveness studies evaluating iron fortification of foods. Results and discussion: In the selected studies, frequently used iron fortificants were NaFeEDTA, ferrous sulfate, and micronized ferric pyrophosphate. Cereal-based products, salt, sauces, fruit juice, and cow’s milk-based foods were used as food vehicles. It is believed that native dietary iron and fortification iron do not pose a risk of iron overload due to a tight regulation of iron absorption in normal subjects. However, iron intake exceeding iron requirements might lead to increased risk of cardiovascular diseases and colorectal cancer.
Conclusions: Regular intake of iron-fortified foods is effective in curing nutritional iron deficiency. Such interventions should be targeted at people with low iron status who fail to improve their iron deficiency by means of dietary modification.

Fardin-Kia AR, Delmonte P, Kramer JKG, Jahreis G, Kuhnt K, Santercole V, Rader JI (2013) Separation of the fatty acids in Menhaden oil as methyl esters with a highly polar ionic liquid gas chromatographic column and identification by time of flight mass spectrometry. Lipids 48 (2013) 1279-1295, DOI 10.1007/s11745-013-3830-2
The fatty acids contained in marine oils or products are traditionally analyzed by gas chromatography using capillary columns coated with polyethylene glycol phases. Recent reports indicate that 100 % cyanopropyl siloxane phases should also be used when the analyzed samples contain trans fatty acids. We investigated the separation of the fatty acid methyl esters prepared from menhaden oil using the more polar SLB-IL111 (200 m 9 0.25 mm) ionic liquid capillary column and the chromatographic conditions previously optimized for the separation of the complex mixture of fatty acid methyl esters prepared from milk fat. Identifications of fatty acids were achieved by applying Ag+-HPLC fractionation and GC-TOF/MS analysis in CI+ mode with isobutane as the ionization reagent. Calculation of equivalent chain lengths confirmed the assignment of double bond positions. This methodology allowed the identification of 125 fatty acids in menhaden oil, including isoprenoid and furanoid fatty acids, and the novel 7-methyl-6-hexadecenoic and 7-methyl-6-octadecenoic fatty acids. The chromatographic conditions applied in this study showed the potential of separating in a single 90-min analysis, among others, the short chain and trans fatty acids contained in dairy products, and the polyunsaturated fatty acids contained in marine products.

Bähr Melanie, Fechner Anita, Krämer Julia, Kiehntopf Michael, Jahreis Gerhard: Lupin protein positively affects plasma LDL cholesterol and LDL:HDL cholesterol ratio in hypercholesterolemic adults after four weeks of supplementation: a randomized, controlled crossover study. Nutrition Journal 2013, 12:107 doi:10.1186/1475-2891-12-107
Background: A couple of studies indicate a favorable impact of lupin protein on cardiovascular risk factors in humans. These studies, however, used relatively high doses of > 33 g/d, which can hardly be consumed under physiological conditions. Therefore, we investigated the effect of 25 g/d lupin protein isolate (LPI) on selected cardiovascular markers and on serum amino acids.
Methods: A total of 33 hypercholesterolemic subjects participated in a randomized, controlled, double-blind crossover study. LPI and the active comparator milk protein isolate (MPI) were incorporated in protein drinks and consumed over 8 wk separated by a 4 wk washout period. Anthropometric data, blood pressure, and nutrient intake were assessed at baseline and after 8 wk of both protein interventions. Blood was sampled at baseline, wk 4 and wk 8. All 33 subjects were included in final statistical analyses using repeated measures ANOVA with the general linear model or using linear mixed model.
Results: Except for higher HDL cholesterol at wk 4 of LPI (P <= 0.036), anthropometric parameters, blood pressure, and plasma lipids did not differ among LPI and MPI intervention. Compared to baseline, the primary outcome LDL cholesterol was significantly reduced after 4 wk of both interventions (P <= 0.008), while LDL:HDL cholesterol ratio was decreased only by LPI (P = 0.003). These time effects were restricted to subjects with higher hypercholesterolemia and disappeared after 8 wk. Blood pressure was reduced after 8 wk of LPI (P <= 0.044). Almost all serum amino acids were higher at wk 4 but not at wk 8 of MPI compared to LPI. Following 4 wk and 8 wk of LPI intervention, most amino acids remained unchanged. Both interventions caused a slight, but significant rise in body weight and body fat after 8 wk (P <= 0.045).
Conclusion: In conclusion, 25 g LPI can beneficially modulate plasma LDL cholesterol at least over short-term. Using appropriate dietetic conditions that improve consumer compliance and avoid changes in energy intake as well as in body composition, lupin protein could positively impact cardiovascular risk factors particularly in individuals with higher hypercholesterolemia. Trial registration: ClinicalTrials.gov: NCT01304992

Petersen KD, Jahreis G, Busch‐Stockfisch M, Fritsche J. Chemical and sensory assessment of deep‐frying oil alternatives for the processing of French fries. Eur J Lipid Sci Technol 2013, 115, 935–945
The aim of the study was to evaluate volatile compounds as marker compounds for the edible oil deterioration during the production of deep‐fried French fries. Additionally the sensory characteristics (taste and smell) were assessed and results were compared with the results of the volatile compound analysis. A 32‐hdeep‐frying experiment was performed and different frying oils, namely sunflower oil (SF), high‐oleic sunflower oil (HOSF), rapeseed oil (RO), high‐oleic rapeseed oil (HORO), and palm olein, were subsequently analyzed for their oxidative properties by the determination of their total polar material (TPM), polymerized triglycerides (PTG), peroxide value, anisidine value, as well as the fatty acid composition. In addition, analysis of the volatile compounds derived from the thermal degradation of the frying oils was performed by means of headspace‐GC/MS techniques (HS‐SPME‐GC/MS and DHS‐GC/MS). Multivariate statistical methods (principal component analysis with VARIMAX rotation) were applied to identify sensitive volatile lipid degradation indicators, enabling a differentiation of the various frying oils of different degrees of lipid oxidation just after 3 h of deep‐frying. E,E‐2,4‐decadienal and heptanal showed the greatest ability to differentiate between samples of various oxidative states, whereas E,E‐2,4‐heptadienal and E‐2‐decenal showed a reasonable correlation with well‐known lipid oxidation parameters, e.g., values for PTG or TPM. In addition to the chemical evaluation of the frying oils, the produced French fries were evaluated in terms of their taste and smell by an advanced scientific sensory method (balanced incomplete block design). French fries produced in conventional vegetable oils (SF and RO) were differentiated earlier from those prepared in fresh reference oil compared to HOSF and HORO. The perception of the French fries prepared in HOSF was comparable to those prepared in palm olein. Therefore, high‐oleic vegetable oils, especially high‐oleic SF, provide a frying oils alternative for the production of deep‐fried French fries, delivering low proportions of trans and saturated fatty acids.

Trautvetter U, Jahreis G. Effect of supplementary calcium phosphate on plasma gastrointestinal hormones in a double-blind, placebo-controlled, cross-over human study. Br J Nutr. 2013 Jul 22:1-7. [Epub ahead of print]
Gastrointestinal hormones and Ca are associated with bone metabolism. The objective of the present human study was to determine the effect of calcium phosphate on the postprandial circulation of gastrointestinal hormones. A total of ten men participated in the present double-blind, placebo-controlled, cross-over study. The participants were divided into two groups. Of these, one group consumed bread enriched with 1 g Ca (pentacalcium hydroxy-triphosphate, CaP) daily for 3 weeks. The other group consumed placebo bread. After 2 weeks of washout, the intervention was changed between the groups for another 3 weeks. The subjects consumed a defined diet at the beginning (single administration) and at the end (repeated administration) of the intervention periods, and blood samples were drawn at 0, 30, 60, 120, 180 and 240 min. Between 0 and 30 min, the participants consumed a test meal, with or without CaP. The concentrations of gastrointestinal hormones (glucose-dependent insulinotropic polypeptide, glucagon-like peptide (GLP) 1 and GLP2), insulin and glucose were determined. The AUC of GLP1 (total and active) and GLP2 increased significantly after the repeated CaP administrations compared with that after placebo administration. The AUC of insulin and glucose showed no differences between the CaP and placebo administrations. CaP affects the postprandial plasma concentrations of gastrointestinal hormones through the modulation of the intestinal environment, e.g. bile acids and microbiota

Trautvetter U, Kiehntopf M, Jahreis G. Postprandial effects of calcium phosphate supplementation on plasma concentration-double-blind, placebo-controlled cross-over human study. Nutr J. 2013 Mar 8;12:30. doi: 10.1186/1475-2891-12-30.
BACKGROUND: The aim of the present study was to examine the postprandial calcium and phosphate concentrations after supplementation with pentacalcium hydroxy-triphosphate (CaP).
METHODS: Ten men participated in this double-blind, placebo-controlled, cross-over study. The participants were divided into two groups. One group consumed bread enriched with CaP (plus 1 g calcium/d) and the other group a placebo product for three weeks. After a two week wash-out, the intervention was switched between the groups for another three weeks. Blood samples were drawn at the beginning (single administration) and at the end (repeated administration) of the intervention periods at 0, 30, 60, 120, 180 and 240 min. Between 0 and 30 min, a test meal, with or without CaP was consumed. The plasma concentrations of calcium and phosphate were examined. One participant dropped out due to personal reasons.
RESULTS: CaP supplementation resulted in a significantly higher plasma calcium concentration after 240 min compared to placebo. After repeated CaP administration, the AUC for the increment in plasma calcium concentration was significantly higher compared to placebo.After single and repeated CaP supplementation, plasma phosphate concentration significantly decreased after 30, 60, 120 and 180 min compared to 0 min. The placebo administration resulted in significant decreases after 30, 60 and 120 min compared to 0 min.
CONCLUSION: Our results show that CaP contributes to an adequate calcium supply, but without increasing the plasma concentration of phosphate.
TRIAL REGISTRATION: www.clinicaltrials.gov; NCT01296997.

Fechner A, Fenske K, Jahreis G. Effects of legume kernel fibres and citrus fibre on putative risk factors for colorectal cancer: a randomised, double-blind, crossover human intervention trial. Nutrition Journal. 2013, 12:101. DOI: 10.1186/10.1186/1475-2891-12-101
Background: In some studies, high intake of dietary fibre has been associated with a lower risk of colorectal cancer. The present study aimed to compare physiological effects of three legume kernel fibres and citrus fibre on blood lipids (primary outcome: LDL cholesterol) and colonic health.
Methods: Ninety-two subjects were recruited for the double-blind, controlled crossover trial. Seventy-eight participants were randomly divided into three groups. Following run-in, half the volunteers from each group consumed 25 g/d of a legume fibre, comprising blue lupin fibre, white lupin fibre, and soya fibre for two weeks. The other half received the same amount of citrus fibre (active comparator). The intervention was crossed within each group after two weeks wash-out. At the end of run-in and intervention, a quantitative faeces collection took place and fasting blood samples were drawn. Repeated measures ANOVA with the general linear model were applied to evaluate changes following interventions.
Results: Seventy-six subjects completed the study. Dietary fibre intake during all interventions was approximately twice the fibre intake at run-in. The lupin fibre supplementations increased daily faecal dry matter and faecal weight compared to run-in, representing an increase of 1.76 g faeces/g additional dietary fibre contributed by blue lupin and of 1.64 g faeces/g by white lupin, respectively. Both lupin interventions led to a significantly enhanced formation of short-chain fatty acids, and blue lupin fibre to a decrease in faecal pH compared to run-in (0.27 units, P< 0.01). Further, blue lupin increased primary bile acids-excretion (P = 0.02). All legume fibres reduced faecal concentrations of total and secondary bile acids (blue lupin: 16%; white lupin: 24%; soya: 16%). Blood lipids were not influenced by any intervention. No serious adverse effects were observed.
Conclusions: The tested fibre preparations do not affect lipid metabolism through bile acid-binding in normocholesterolaemic subjects. However, particularly blue lupin kernel fibre improve colonic function and have beneficial effects on putative risk factors for colorectal cancer such as faecal mass, transit time, SCFA, faecal pH, and secondary bile acid concentration. Therefore, enhancing dietary fibre intake through blue lupin up to about 50 g/d can be recommended.
Trial registration: NCT01036308

Kramer R, Wolf S, Petri T, von Soosten D, Dänicke S, Weber EM, Zimmer R, Rehage J, Jahreis G. A commonly used rumen-protected conjugated linoleic acid supplement marginally affects fatty acid distribution of body tissues and gene expression of mammary gland in heifers during early lactation. Lipids Health Dis. 2013 Jul 4;12(1):96. [Epub ahead of print]
BACKGROUND: Conjugated linoleic acids (CLA) in general, and in particular the trans-10,cis-12 (t10,c12-CLA) isomer are potent modulators of milk fat synthesis in dairy cows. Studies in rodents, such as mice, have revealed that t10,c12-CLA is responsible for hepatic lipodystrophy and decreased adipose tissue with subsequent changes in the fatty acid distribution. The present study aimed to investigate the fatty acid distribution of lipids in several body tissues compared to their distribution in milk fat in early lactating cows in response to CLA treatment. Effects in mammary gland are further analyzed at gene expression level.
METHODS: Twenty-five Holstein heifers were fed a diet supplemented with (CLA groups) or without (CON groups) a rumen-protected CLA supplement that provided 6 g/d of c9,t11- and t10,c12-CLA. Five groups of randomly assigned cows were analyzed according to experimental design based on feeding and time of slaughter. Cows in the first group received no CLA supplement and were slaughtered one day postpartum (CON0). Milk samples were taken from the remaining cows in CON and CLA groups until slaughter at 42 (period 1) and 105 (period 2) days in milk (DIM). Immediately after slaughter, tissue samples from liver, retroperitoneal fat, mammary gland and M. longissimus (13th rib) were obtained and analyzed for fatty acid distribution. Relevant genes involved in lipid metabolism of the mammary gland were analyzed using a custom-made microarray platform.
RESULTS: Both supplemented CLA isomers increased significantly in milk fat. Furthermore, preformed fatty acids increased at the expense of de novo-synthesized fatty acids. Total and single trans-octadecenoic acids (e.g., t10-18:1 and t11-18:1) also significantly increased. Fatty acid distribution of the mammary gland showed similar changes to those in milk fat, due mainly to residual milk but without affecting gene expression. Liver fatty acids were not altered except for trans-octadecenoic acids, which were increased. Adipose tissue and M. longissimus were only marginally affected by CLA supplementation.
CONCLUSIONS: Daily supplementation with CLA led to typical alterations usually observed in milk fat depression (reduction of de novo-synthesized fatty acids) but only marginally affected tissue lipids. Gene expression of the mammary gland was not influenced by CLA supplementation.

Steinert RE, Peterli R, Keller S, Meyer-Gerspach AC, Drewe J, Peters T, Beglinger C. Bile acids and gut peptide secretion after bariatric surgery - A 1-year prospective randomized pilot trial. Obesity (2013), doi: 10.1002/oby.20522.
Objective: Increased delivery of bile acid salts (BA) to distal L-cells and altered TGR5 receptor activation may contribute to the early and substantial increases in gut peptide secretion seen after bariatric surgery. To further elucidate a potential role of BA in the secretion of GLP-1 and PYY, we analyzed plasma BA concentrations in 14 morbidly obese patients undergoing gastric bypass or sleeve gastrectomy in a prospective, randomized 1-year trial. Design and Methods: Patients received a standard test meal and blood was collected before and after eating, prior to, and 1 week, 3 months, and 12 months after surgery. Results: Pre-surgery, basal BA concentrations were significantly lower in bariatric patients than in healthy controls. One year post-surgery, bariatric patients expressed variably increased BA concentrations (gastric bypass patients ˜2 fold increase, p≤0.05). However, whereas in both patient groups, marked increases in GLP-1 and PYY and improved glycemic control was seen already 1 week and 3 months post-surgery, changes in plasma BA followed a different pattern - basal and postprandial plasma BA concentrations increased much slower, more progressively with significant increases only 1 year post-surgery. Conclusions: Based on these findings, BA do not appear to be key mediators of the early increase in GLP-1 and PYY response in postbariatric patients.

Meyer-Gerspach AC, Steinert RE, Keller S, Malarski A, Schulte FH, Beglinger C. Effects of Chenodeoxycholic Acid on the Secretion of Gut Peptides and Fibroblast Growth Factors in Healthy Humans. J Clin Endocrinol Metab (2013), doi:10.1210/jc.2012-4109
Context:Recent evidence suggests bile acids (BAs) are involved in the glycemic control via TGR5 activation with the subsequent release of gut peptides and farnesoid X receptor activation with ensuing release of fibroblast growth factors (FGFs).Objective:We hypothesized that intraduodenal infusions of chenodeoxycholic acid (CDCA) would stimulate FGF and gut peptide secretion, thereby positively influencing glucose homeostasis.Design, Setting, Participants, and Intervention:This randomized, double-blind, placebo-controlled, crossover trial included 12 healthy volunteers who received intraduodenal infusions (2.0 mL/min for 180 minutes) of saline, CDCA (5 or 15 mmol/L), and a fatty acid (sodium oleate), either alone or with 5 mmol/L CDCA. After 60 minutes, an oral glucose tolerance test (oGTT) was performed.Main Outcome Measures:Plasma levels of glucagon-like peptide-1 (GLP-1), peptide tyrosine tyrosine, cholecystokinin (CCK), total BAs, FGF19, FGF21, C-peptide, insulin, glucose, and glucagon were measured.Results:Within the first 60 minutes, high-concentration CDCA induced a small but significant increase in GLP-1 and CCK secretion (P = .016 and P =.011), whereas plasma C-peptide, insulin, and glucose were not affected. Attenuated C-peptide and insulin release was observed after the oGTT with 15 mmol/L CDCA (P = .013 and P =.011). Plasma BA and FGF19 levels significantly increased after CDCA administration (P = .001 and P < .001).Conclusions:CDCA modulates GLP-1 and CCK secretion; the effect is small and does not influence glucose levels. The marked increase in plasma BAs and the attenuated insulin release after the oGTT indicate the role of BAs in glycemic control, independent of the incretin axis, and suggest involvement of farnesoid X receptor activation pathways.

Jahreis G, Wohlgemuth S, Grünz G, Martin L, Knieling M, Engel R, Türk M, Keller S. Dietary crystalline common-, micro-, nanoscale and emulsified nanoscale sitosterol reduce equally the cholesterol pool in guinea pigs, but varying nanosystems result in different sterol concentrations in serosal jejunum. Nanomedicine-Nanotechnology Biology and Medicine 9 (2013) 1027-1035.  
Due to hypocholesterolemic effects, sitosterol is used in functional foods and nanoscale dispersions. To investigate the influence of dietary sitosterol on sterol concentrations in Dunkin Hartley guinea pigs, seven groups consisting of eight animals each were fed either a basal diet (BD), a high-cholesterol diet (HC) or a high-cholesterol diet supplemented with crystalline commonscale (CCS), microscale (CMS, low-dosed: CMLS), nanoscale (CNS) or emulsified nanoscale (ENS) sitosterol. When compared to HC group, all sitosterol formulations decreased liver cholesterol concentrations. No differences in cholesterol or sitosterol concentration were found in plasma and liver between CCS, CMS, CNS, and ENS groups. Apparent cholesterol digestibility decreased by increasing crystalline microscale sitosterol doses. Despite a lower sitosterol intake, ENS group had higher serosal sitosterol concentrations in jejunum than CNS group. To elucidate an impact of the sitosterol nanosystem on gut tissues further studies are necessary.

Fleddermann M, Fechner A, Rößler A, Bähr M, Pastor A, Liebert F, Jahreis G. Nutritional evaluation of rapeseed protein compared to soy protein for quality, plasma amino acids, and nitrogen balance - A randomized cross-over intervention study in humans. Clinical Nutrition  32 (2013) 519-526
BACKGROUND & AIMS: Plant proteins such as rapeseed have received little attention for human nutrition due to their high level of antinutritive compounds. Today, newer technologies can eliminate such compounds. The present intervention study aimed to evaluate nutritional and physiological properties of two manufactured canola proteins with special focus on their bioavailability in humans.
METHODS:
28 healthy male subjects (ø 25 years) consumed 30.0 g protein (canola protein isolate - CPI, canola protein hydrolyzate - CPH or soy protein isolate - SPI) in a randomized, double-blind, cross-over study. Blood samples were regularly drawn over the 8-h postprandial period and a 24-h urine sample was collected.
RESULTS: True digestibility of the canola proteins determined in a separate rat assay showed 93.3% for CPI and 97.3% for CPH. In humans, consumption of either 30.0 g canola protein or soy protein mixed in a drink led to significant increases in plasma amino acids after 62.3 and 83.6 min, respectively. While the CPH produced an earlier response compared to CPI and SPI, total amino acid response (AUC for 8 h) was comparable between all interventions. The nitrogen balance between the three proteins tested showed no statistical differences.
CONCLUSIONS: High digestibility of rapeseed protein was found in rats. In humans, this is the first intervention study showing rapeseed protein (both isolate and hydrolyzate) as having a high nutritional quality and can be considered to be as efficient as soy protein for a postprandial amino acid response. This trial was registered at ClinicalTrials.gov Identifier: NCT01481584.

Mouritsen Ole G., Dawczynski Christine, Duelund Lars, Jahreis Gerhard, Vetter Walter, Schröder Markus: On the human consumption of the red seaweed dulse (Palmaria palmata (L.) Weber & Mohr). J Appl Phycol 25 (2013) 1777-1791.
The red seaweed dulse (Palmaria palmata) is one of the more popular seaweed species for human consumption in the Western world. With a documented historical use up to present days in Ireland, Brittany (France), Iceland, Maine (USA), and Nova Scotia (Canada), it has remained a snack, a food supplement, and an ingredient in various dishes. The trend towards more healthy and basic foodstuffs, together with an increasing interest among chefs for the seaweed cuisine, has posed the need for more quantitative knowledge about the chemical composition of dulse of relevance for human consumption. Here, we report on data for amino acid composition, fatty acid profile, vitamin K, iodine, kainic acid, inorganic arsenic, as well as for various heavy metals in samples from Denmark, Iceland, and Maine.

Arnold C, Winter L, Fröhlich K, Jentsch S, Dawczynski J, Jahreis G, Böhm V. Macular xanthophylls and ω-3 long-chain polyunsaturated fatty acids in age-related macular degeneration: A randomized trial. JAMA Ophthalmol. 2013 Mar 21:1-9. doi: 10.1001/jamaophthalmol.2013.2851.
IMPORTANCE It has been shown that the functionality of the macula lutea depends on the nutritional uptake of lutein and zeaxanthin and that it is inversely associated with the risk of age-related macular degeneration (AMD). Additionally, ω-3 long-chain polyunsaturated fatty acids (LC-PUFAs) may also be protective. OBJECTIVE To investigate the effect of a 12-month intervention with macular xanthophylls and ω-3 LC-PUFAs on xanthophylls and fatty acids in plasma, antioxidant capacity, and optical density of the macular pigment of patients with nonexudative AMD. DESIGN The LUTEGA study was a randomized, double-blind, placebo-controlled, parallel clinical trial that was conducted for 12 months. SETTING University Eye Hospital and Institute of Nutrition, Friedrich Schiller University Jena, Germany. PARTICIPANTS A total of 172 individuals with nonexudative AMD. INTERVENTION Individuals were enrolled and randomly divided as follows: placebo group, group 1 (a capsule containing 10 mg of lutein, 1 mg of zeaxanthin, 100 mg of docosahexaenoic acid, and 30 mg of eicosapentaenoic acid administered each day), and group 2 (same substances but twice the dose used in group 1). One hundred forty-five participants completed the study successfully. MAIN OUTCOME MEASURES Plasma xanthophyll concentrations and fatty acid profiles, optical density of the macular pigment, and antioxidant capacity in plasma (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid [Trolox] equivalent antioxidant capacity and photochemiluminescence). RESULTS The concentrations of the administered carotenoids in plasma as well as the optical density of the macular pigment increased significantly in the groups randomized to receive supplementary macular xanthophylls and ω-3 LC-PUFAs after 1 month of intervention and remained at this level through the end of the study. Use of the double dose resulted in a beneficial alteration of the fatty acid profile in the plasma of patients with AMD in comparison with the dose in group 1. The lipophilic antioxidant capacity in plasma was significantly elevated with the intervention. CONCLUSIONS AND RELEVANCE A supplement containing a fixed combination of lutein, zeaxanthin, and ω-3 LC-PUFAs during 12 months significantly improved plasma antioxidant capacity, circulating macular xanthophyll levels, and the optical density of the macular pigment. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00763659.

Jaudszus A, Gruen M, Watzl B, Ness C, Roth A, Lochner A, Barz D, Gabriel H, Rothe M, Jahreis G. Evaluation of suppressive and pro-resolving effects of EPA and DHA in human primary monocytes and T-helper cells. J Lipid Res 54 (2013) 923-935
Besides their health beneficial anti-inflammatory properties, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may increase the infection risk at high doses, likely by generating an immune-depressed state. To assess the contribution of different immune cell populations to the immunomodulatory fatty acid effect, we comparatively investigated several aspects of inflammation in human T-helper (Th) cells and monocytes. Both fatty acids, but DHA to a lesser extent compared to EPA, selectively and dose-dependently reduced the percentage of cytokine expressing Th cells in a PPARγ-dependent fashion, whereas the expression of the cell surface marker CD69 was unaltered on activated T cells. In monocytes, both EPA and DHA increased IL-10 without affecting TNF-α and IL-6. Cellular incorporation of EPA and DHA occurred mainly at the expense of arachidonic acid. Concomitantly, TXB2 and LTB4 in supernatants decreased, while levels of TXB3 and LTB5 increased. This increase was independent of activation and in accordance with cyclooxygenases expression patterns in monocytes. Moreover, EPA and DHA gave rise to a variety of mono- and trihydroxy derivatives of highly anti-inflammatory potential, such as resolvins and their precursors. Our results suggest that EPA and DHA do not generally affect immune cell functions in an inhibitory manner but rather promote pro-resolving responses.

C Dawczynski, KA Massey, C Ness, M Kiehntopf, S Stepanow, M Platzer, M Grün, A Nicolaou, G Jahreis (2013) Randomized placebo-controlled intervention with n-3 LC-PUFA-supplemented yoghurt: Effects on circulating eicosanoids and cardiovascular risk factors, Clin Nutr 32: 686-696 DOI: 10.1016/j.clnu.2012.12.010.
Background & aims: The study examined the value of n-3 LC-PUFA-enriched yogurt as means of improving cardiovascular health.
Design: Fifty three mildly hypertriacylglycerolemic subjects (TAG ≥ 1.7 mmol/L) participated in a randomized, placebo-controlled, double-blind, parallel designed study. The subjects consumed 1) control yoghurt; 2) yoghurt enriched with 0.8 g n-3 LC-PUFA/d; or 3) yoghurt enriched with 3 g n-3 LC-PUFA/d for a period of 10 wks. Blood samples were taken at the beginning and the end of the study period.
Results: Following daily intake of 3 g n-3 LC-PUFA for 10 weeks, n-3 LC-PUFA levels increased significantly in plasma and red blood cells (RBC) with concomitant increase in the EPA-derived mediators (PGE3, 12-, 15-, 18-HEPE) in plasma whilst cardiovascular risk factors such as HDL, TAG, AA/EPA ratio, and n-3 index were improved (P < 0.05); the decrease of TAG and increase in HDL were associated with the CD36 genotype.
Conclusion: The observed increase of n-3 LC-PUFA in RBC and plasma lipids due to intake of n-3 LC-PUFA enriched yoghurt resulted in a reduction of cardiovascular risk factors and inflammatory mediators showing that daily consumption of n-3 PUFA enriched yoghurt can be an effective way of supplementing the daily diet and improving cardiovascular health.

ClinicalTrials.govIdentifier: NCT01244048

2012

M Fleddermann, A Fechner, A Rößler, M Bähr, A Pastor, F Liebert, G Jahreis (2012) Nutritional evaluation of rapeseed protein compared to soy protein for quality, plasma amino acids, and nitrogen balance - A randomized cross-over intervention study in humans. Clin Nutr. [Epub ahead of print]

BACKGROUND & AIMS: Plant proteins such as rapeseed have received little attention for human nutrition due to their high level of antinutritive compounds. Today, newer technologies can eliminate such compounds. The present intervention study aimed to evaluate nutritional and physiological properties of two manufactured canola proteins with special focus on their bioavailability in humans.

METHODS: 28 healthy male subjects (ø 25 years) consumed 30.0 g protein (canola protein isolate - CPI, canola protein hydrolyzate - CPH or soy protein isolate - SPI) in a randomized, double-blind, cross-over study. Blood samples were regularly drawn over the 8-h postprandial period and a 24-h urine sample was collected.

RESULTS: True digestibility of the canola proteins determined in a separate rat assay showed 93.3% for CPI and 97.3% for CPH. In humans, consumption of either 30.0 g canola protein or soy protein mixed in a drink led to significant increases in plasma amino acids after 62.3 and 83.6 min, respectively. While the CPH produced an earlier response compared to CPI and SPI, total amino acid response (AUC for 8 h) was comparable between all interventions. The nitrogen balance between the three proteins tested showed no statistical differences.

CONCLUSIONS: High digestibility of rapeseed protein was found in rats. In humans, this is the first intervention study showing rapeseed protein (both isolate and hydrolyzate) as having a high nutritional quality and can be considered to be as efficient as soy protein for a postprandial amino acid response. This trial was registered at ClinicalTrials.gov Identifier: NCT01481584.

 

Strobel C, Jahreis G, Kuhnt K. (2012) Survey of n-3 and n-6 polyunsaturated fatty acids in fish and fish products. Lipids Health Dis. 2012 Oct 30;11(1):144. [Epub ahead of print]
BACKGROUND: The imbalance of the n-3/n-6 ratio in the Western diet is characterised by a low intake of n-3 long-chain (LC) PUFA and a concurrent high intake of n-6 PUFA. Fish, in particular marine fish, is a unique source of n-3 LC PUFA. However, FA composition of consumed fish changed, due to the increasing usage of n-6 PUFA-rich vegetable oils in aquaculture feed and in fish processing (frying) which both lead to a further shift in n-6 PUFA to the detriment of n-3 LC PUFA.The aim of this study was to determine the ratio of n-3/n-6 including the contents of EPA and DHA in fish fillets and fish products from the German market (n=123). Furthermore, the study focussed on the FA content in farmed salmon compared to wild salmon as well as in processed Alaska pollock fillet, e.g., fish fingers.
RESULTS: Total fat and FA content in fish products varied considerably depending on fish species, feed management, and food processing. Mackerel, herring and trout fillets characteristically contained adequate dietary amounts of absolute EPA and DHA, due to their high fat contents. However, despite a lower fat content, tuna, pollock, and Alaska pollock can contribute considerable amounts of EPA and DHA to the human supply.Farmed salmon are an appropriate source of EPA and DHA owing to their higher fat content compared to wild salmon (12.3 vs. 2.1 wt %), however with elevated SFA, n-9 and n-6 FA contents representing the use of vegetable oils and oilseeds in aquaculture feed. The n-3/n-6 ratio was deteriorated (2.9 vs. 12.4) but still acceptable. Compared to pure fish fillets, breaded and pre-fried Alaska pollock fillet contained extraordinarily high fat and n-6 PUFA levels.
CONCLUSIONS: Since fish species vary with respect to their n-3 LC PUFA contents, eating a variety of fish is advisable. High n-6 PUFA containing pre-fried fish support the imbalance of n-3/n-6 ratio in the Western diet. Thus, consumption of pure fish fillets is to be favoured. The lower n-3 PUFA portion in farmed fish can be offset by the higher fat content, however, with an unfavourable FA distribution compared to wild fellows.

Degen C, Habermann N, Piegholdt S, Glei M, Jahreis G (2012) Human colon cell culture models of different transformation stages to assess conjugated linoleic acid and conjugated linolenic acid metabolism: Challenges and chances. Toxicol In Vitro. 26:985-92.
Both cellular transformation status and cell culture conditions affect fatty acid metabolism. Hence, the incorporation and metabolism of c9,t11-CLA (conjugated linoleic acid) and other CFAs (conjugated fatty acids) were compared in colon cells (LT-97, adenoma; HT-29, adenocarcinoma). Growth inhibition by CFA in LT-97 cells was assessed via the DAPI (4',6-diamidino-2-phenylindole dihydrochloride) assay. Basal gene expression of desaturases (Δ5, Δ6 and Δ9) and elongases (1, 2, 5 and 6) was determined in LT-97 using PCR. Analysis of cellular fatty acids revealed a 2-fold higher incorporation of c9,t11-CLA (40 and 80μM) in HT-29 cells compared to LT-97 cells. The β-oxidized and elongated conjugated dienoic (CD) fatty acids differed by 8-fold (CD-C16:2/CD-C20:2; HT-29: 8:1; LT-97: 1:1). Notably, LT-97 cells were shown to convert conjugated linolenic acid (CLnA) to CLA. Moreover, LT-97 cells revealed no basal expression of elongase 2. CLnA caused stronger growth inhibition (80μM) compared to CLA (200μM). The results indicate that LT-97 cells represent a superior model to carry out elongation and desaturation studies of unsaturated and conjugated fatty acids compared to HT-29 cells. Nevertheless, further in-depth metabolic and transcriptomic analyses are required to confirm this suggestion.

T Baars, J Wohlers, D Kusche, G Jahreis (2012) Experimental inprovement of cow milk fatty acid composition in organic winter diets. J Sci Food Agric 92, 2883-2890

BACKGROUND: Organic milk is seen as more healthy in terms of its fatty acid (FA) profile. In three on-farm crossover trials with 10-12 cows in each group, different forages were compared for their potential to improve the FA composition. Different hay qualities (hay of pasture vs. hay of leys), additional energy sources (fodder beets vs. wheat) and roughage qualities (hay of pasture vs. grass silage) were compared for their effect on the FA composition of the milk.

RESULTS: Rumenic acid (CLA cis-9, trans-11) and α-linolenic acid (ALA) were selected as principal markers to evaluate effects. The overall CLA cis-9, trans-11 was low (3.6-6.3 g kg(-1) fat), whereas ALA levels were intermediate (6.8-9.4 g kg(-1) fat). Differences between the forages were explained by the fat metabolism of the ruminants.

CONCLUSION: Organic winter milk is low in several desirable FAs. Diets rich in mature fodder and sugar were a poor choice for an improved FA composition.

Grądzka I, Sochanowicz B, Brzóska K, Wójciuk G, Sommer S, Wojewódzka M, Gasińska A, Degen C, Jahreis G, Szumiel I. (2012) Cis-9, trans-11 conjugated linoleic acid affects lipid raft composition and sensitizes human colorectal adenocarcinoma HT-29 cells to X-radiation. Biochim Biophys Acta.2012 Oct 29. [Epub ahead of print]
BACKGROUND: Investigations concerned the mechanism of HT-29 cells radiosensitization by cis-9,trans-11-conjugated linoleic acid (c9,t11-CLA), a natural component of human diet with proven antitumor activity.
METHODS: The cells were incubated for 24hours with 70μM c9,t11-CLA and then X-irradiated. The following methods were used: gas chromatography (incorporation of the CLA isomer), flow cytometry (cell cycle), cloning (survival), Western blotting (protein distribution in membrane fractions), pulse-field gel electrophoresis (rejoining of DNA double-strand breaks). In parallel, DNA-PK activity, γ-H2AX foci numbers and chromatid fragmentation were estimated. Gene expression was analysed by RT-PCR and chromosomal aberrations - by the mFISH method. Nuclear accumulation of the EGF receptor (EGFR) was monitored by ELISA.
RESULTS AND CONCLUSIONS: C9,t11-CLA sensitized HT-29 cells to X-radiation. This effect was not due to changes in cell cycle progression or DNA-repair-related gene expression. Post-irradiation DSB rejoining was delayed, corresponding with the insufficient DNA-PK activation, although chromosomal aberration frequencies did not increase. Distributions of cholesterol and caveolin-1 in cellular membrane fractions changed. The nuclear EGFR translocation, necessary to increase the DNA-PK activity in response to oxidative stress, was blocked. We suppose that c9,t11-CLA modified the membrane structure, thus disturbing the intracellular EGFR transport and the EGFR-dependent pro-survival signalling, both functionally associated with lipid raft properties.
GENERAL SIGNIFICANCE: The results point to the importance of the cell membrane interactions with the nucleus after injury inflicted by X -rays. Compounds like c9,t11-CLA, that specifically alter membrane properties, could be used to develop new anticancer strategies.

Renner L, Pappritz J, Kramer R, Döll S, Jahreis G, Dänicke S (2012) Fatty acid profile and proliferation of bovine blood mononuclear cells after conjugated linoleic acid supplementation. Lipids Health Dis 11:63. [Epub ahead of print]
BACKGROUND: Conjugated linoleic acids (CLA) are in focus of dairy cattle research because of its milk fat reducing effects. Little is known about the impact of CLA on immune function in dairy cows. Therefore, in the present study we investigated the effects of a long term supplementation of dairy cows with CLA on the fatty acid profile of peripheral blood mononuclear cells (PBMC) and their proliferation ex vivo.
RESULTS: The supplementation of dairy cows with either 100 g/d of a control fat preparation (CON,n = 15), 50 g/d of the control fat preparation and 50 g/d CLA supplement - containing 12.0 % cis-9,trans-11 and 11.9 % trans-10,cis-12 CLA of total fatty acid methyl esters - (CLA-50, n = 15) or 100 g/d of the CLA supplement (CLA-100, n = 16) did not influence the major fatty acids (C18:0, C16:0, cis-9 C18:1, cis-9,cis-12 C18:2, cis-5,cis-8,cis-11,cis-14 C20:4) in the lipid fraction of PBMC. The proportion of trans-10,cis-12 CLA of total fatty acids was increased in both CLA supplemented groups, but there was no effect on the cis-9,trans-11 isomer. Furthermore, the proportion of trans-9 C18:1 and cis-12 C24:1 was reduced in the CLA-100 group. The mitogen stimulated cell proliferation was not influenced by CLA feeding.
CONCLUSION: CLA supplementation influenced the FA profile of some minor FA in PBMC, but these changes did not lead to differences in the mitogen induced activation of the cells.

Dänicke S, Kowalczyk J, Renner L, Pappritz J, Meyer U, Kramer R, Weber EM, Döll S, Rehage J, Jahreis G (2012) Effects of conjugated linoleic acids fed to dairy cows during early gestation on hematological, immunological, and metabolic characteristics of cows and their calves. J Dairy Sci 95:3938-53.
The aim of the present experiment was to test the stimulation ability of peripheral blood mononuclear cells (PBMC) expressed as stimulation index (SI) of newborn calves and of their dams fed a control fat supplement (CON, n=6) or 50 and 100g/d of a CLA-containing fat supplement (CLA50, n=5, and CLA100, n=6, respectively) during the preceding lactation period for 182d after calving. The total intake of cis-9,trans-11 and trans-10,cis-12 CLA by groups CLA50 and CLA100 amounted to 4 and 8g/d each, respectively. For this purpose, blood was collected immediately after parturition from calves before and after colostrum intake, and from cows after parturition and 21d later. The SI was related to the fatty acid composition of erythrocyte and milk lipids and to various hematological and clinical-chemical parameters. Retrospective evaluation revealed that depletion time (i.e., the individual period elapsed between the day of terminating the feeding of the experimental diet in the preceding lactation period and the day of calving) ranged from 190 to 262d, which corresponded to fetal exposure times of 19 to 102d. The SI from cows increased significantly by 77 and 55%, within 21d after calving according to the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and Alamar Blue assays, respectively. However, feeding of 50g of the CLA product failed to demonstrate this increase in the MTT assay. Moreover, SI was significantly lower for calves whose dams belonged to the CLA50 group, whereas stimulation ability was comparable for the PBMC from calves whose mothers were treated with CON and CLA100. Plasma metabolites (total bilirubin, total cholesterol, glucose, nonesterified fatty acids, 3-β-hydroxybutyrate, total protein, and albumin) and hematological parameters (hematocrit, white blood cell profile) were not significantly influenced by dietary treatments of the cows in the preceding lactation period. Although the fatty acid pattern of erythrocyte lipids of cows remained uninfluenced, that of calves showed alterations due to the feeding type of their dams. For example, C16:0 increased significantly from 14.4 to 16.9% of total fatty acid methyl esters, whereas cis-9,trans-11 CLA increased slightly from 0.11 to 0.15% at the same time in calves when their mothers were fed the CLA100 instead of the CON diet. Fatty acid profile of colostrum was significantly different from that of milk after 3wk for most of the detected fatty acids, but was not influenced by diet type. In conclusion, feeding a CLA-containing fat supplement during the preceding lactation and gestation period exerted effects on the stimulation ability of PBMC from cows and calves for the subsequent parturition. However, CLA dose effects were inconsistent and require further investigation.

Jaudszus A, Jahreis G, Schlörmann W, Fischer J, Kramer R, Degen C, Rohrer C, Roth A, Gabriel H, Barz D, Gruen M (2012) Vaccenic acid-mediated reduction in cytokine production is independent of c9,t11-CLA in human peripheral blood mononuclear cells. Biochim Biophys Acta - Mol Cell Biol Lipids 1821:1316-1322
The ruminant trans fatty acid vaccenic acid (tVA) favorably alters markers of inflammation. However, it is not yet clear whether these effects are attributed to its endogenous partial conversion to c9,t11-CLA, which is known to possess anti-inflammatory properties. We compared the cytokine reducing potential of tVA to c9,t11-CLA in human T-helper (Th) cells as a main source of cytokine production during inflammation. Secondly, we assessed whether a bioconversion of tVA to c9,t11-CLA via stearoyl-CoA desaturase (SCD) encoded activity takes place in peripheral blood mononuclear cells (PBMC) in order to relate the outcomes of intracellular cytokine measurement to the degree of conversion. TVA reduced the percentage of both IL-2 and TNF-α expressing Th cells significantly, but to a lesser extent compared to c9,t11-CLA, as determined by flow cytometry after alloreactive stimulation of PBMC. Pre-treatment with the selective PPARγ antagonist T0070907 largely re-established the IL-2 and TNF-α positive Th cell population in both tVA and c9,t11-CLA treated cultures. Interestingly, while the portion of tVA dose-dependently increased within the cellular lipid fraction, the initially marginal amount of c9,t11-CLA remained unaltered. However, SCD mRNA although abundantly expressed in PBMC was not regulated by tVA. Conclusively, these results suggest that the cytokine reducing effect of tVA in human T cells is independent of c9,t11-CLA, since no bioconversion occurred. Moreover, the data provide evidence that tVA mechanistically acts in a manner similar to c9,t11-CLA.

S Keller, A Malarski, C Reuther, R Kertscher, M Kiehntopf, G. Jahreis (2012) Milk phospholipid and plant sterol-dependent modulation of plasma lipids in healthy volunteers. Eur J Nutr DOI 10.1007/s00394-012-0427-0
Purpose: Hypolipidemic and/or hypocholesterolemic effects are presumed for dietary milk phospholipid (PL) as well as plant sterol (PSt) supplementation. The aim was to induce changes in plasma lipid profile by giving different doses of milk PL and a combination of milk PL with PSt to healthy volunteers.
Methods: In an open-label intervention study, 14 women received dairy products enriched with moderate (3 g PL/day) or high (6 g PL/day) dose of milk PL or a high dose of milk PL combined with PSt (6 g PL/day + 2 g PSt/day) during 3 periods each lasting 10 days.
Results: Total cholesterol concentration and HDL cholesterol concentration were reduced following supplementation with 3 g PL/day. No significant change in LDL cholesterol concentration was found compared with baseline. High PL dose resulted in an increase of LDL cholesterol and unchanged HDL cholesterol compared with moderate PL dose. The LDL/HDL ratio and triglyceride concentration remained constant within the study. Except for increased phosphatidyl ethanolamine concentrations, plasma PL concentrations were not altered during exclusive PL supplementations. A combined high-dose PL and PSt supplementation led to decreased plasma LDL cholesterol concentration, decreased PL excretion, increased plasma sphingomyelin/phosphatidyl choline ratio, and significant changes in plasma fatty acid distribution compared with exclusive high-dose PL supplementation.
Conclusion: Milk PL supplementations influence plasma cholesterol concentrations, but without changes of LDL/HDL ratio. A combined high-dose milk PL and PSt supplementation decreases plasma LDL cholesterol concentration, but it probably enforces absorption of fatty acids or fatty acid-containing hydrolysis products that originated during lipid digestion.

Trautvetter U, Ditscheid B, Kiehntopf M, Jahreis G (2012) A combination of calcium phosphate and probiotics beneficially influences intestinal lactobacilli and cholesterol metabolism in humans. Clin Nutr. 31:230-237
BACKGROUND & AIMS: The study focuses on the influence of a probiotic supplement alone and in combination with a calcium supplement on faecal lactobacilli colonisation and beneficial health effects such as a lowering of blood cholesterol.
METHODS: Thirty-two men and women participated in the double-blind, placebo-controlled, cross-over study. All participants consumed a probiotic drink containing 10(10)CFU/d Lactobacillus paracasei (LPC37) for four weeks. In addition, one group consumed bread enriched with pentacalcium hydroxy-triphosphate (CaP; 1g Ca/d) and the other group had bread without CaP. After a two-week washout and a two-week placebo period, the intervention was switched for further four weeks.
RESULTS: After intervention with LPC37+CaP, total cholesterol and LDL-cholesterol concentration in plasma decreased significantly compared to LPC37 and placebo. The faecal concentration of L. paracasei and that of all lactobacilli increased significantly after LPC37+CaP and LPC37 compared to placebo. Moreover, secondary bile acids in faeces increased significantly after LPC37+CaP intervention compared to placebo.
CONCLUSIONS: CaP modulates the colonisation of LPC37 in the human gut under combinatory supplementation of CaP and LPC37. The combined supplementation also decreases plasma LDL-cholesterol and the LDL/HDL ratio in healthy, moderately hypercholesterolemic men and women, which could be also due to the CaP supplementation. CLINICAL TRIAL REGISTRATION NUMBER: NCT01033461.

Desmarchelier C, Dahlhoff C, Keller S, Sailer M, Jahreis G, Daniel H. C57Bl/6N mice on a Western diet display reduced intestinal and hepatic cholesterol levels despite a plasma hypercholesterolemia. BMC Genomics 2012 Mar 6;13:84. [Epub ahead of print]
BACKGROUND: Small intestine and liver greatly contribute to whole body lipid, cholesterol and phospholipid metabolism but to which extent cholesterol and phospholipid handling in these tissues is affected by high fat Western-style obesogenic diets remains to be determined.
METHODS: We therefore measured cholesterol and phospholipid concentration in intestine and liver and quantified fecal neutral sterol and bile acid excretion in C57Bl/6N mice fed for 12 weeks either a cholesterol-free high carbohydrate control diet or a high fat Western diet containing 0.03 % (w/w) cholesterol. To identify the underlying mechanisms of dietary adaptations in intestine and liver, changes in gene expression were assessed by microarray and qPCR profiling, respectively.
RESULTS: Mice on Western diet showed increased plasma cholesterol levels, associated with the higher dietary cholesterol supply, yet, significantly reduced cholesterol levels were found in intestine and liver. Transcript profiling revealed evidence that expression of numerous genes involved in cholesterol synthesis and uptake via LDL, but also in phospholipid metabolism, underwent compensatory regulations in both tissues. Alterations in glycerophospholipid metabolism were confirmed at the metabolite level by phospolipid profiling via mass spectrometry.
CONCLUSIONS: Our findings suggest that intestine and liver react to a high dietary fat intake by an activation of de novo cholesterol synthesis and other cholesterol-saving mechanisms, as well as with major changes in phospholipid metabolism, to accommodate to the fat load.

KD Petersen, KK Kleeberg, G Jahreis, J Fritsche (2012) Assessment of the oxidative stability of conventional and high-oleic sunflower oil by means of solid-phase microextraction-gas chromatography. Int J Food Sci Nutr 63, 160-169
Headspace-solid-phase microextraction-gas chromatography (HS-SPME-GC) was used to identify in total 74 volatile lipid oxidation compounds altogether in thermally stressed conventional and high-oleic sunflower (HOSF) oil samples (in accelerated storage conditions for 14 days at 80°C). Out of the volatile compounds identified, six volatile compounds were selected as marker compounds for the assessment of lipid oxidation of sunflower (SF) and HOSF oils due to their low odour threshold values and fatty-rancid odour impression. Additionally, other oxidation parameters such as fatty acid composition, peroxide value (PV), anisidine value and tocopherol and tocotrienol composition were determined. Multivariate statistical methods (principal component analysis and agglomerative hierarchical cluster analysis) were applied to identify sensitive oxidation marker compounds. Preliminary results revealed that hexanal, E-2-heptenal, E-2-decenal and E,E-2,4-nonadienal were the most suitable in differentiating HOSF and SF oil varieties from each other and SF samples with differing oxidative properties. Differentiation of SF samples according to their volatile compound composition was done in accordance with the results from the well-known oil quality parameters (e.g. PV or fatty acid composition). In conclusion, the combination of volatile compound analysis with HS-SPME-GC and multivariate statistical methods provides a sensitive tool in differentiating conventional SF and HOSF oils by means of volatile lipid oxidation marker compounds.

M Köhler, A Fechner, M Leiterer, K Spörl, T Remer, U Schäfer, G Jahreis (2012) Iodine content in milk from German cows and in human milk: new monitoring study. Trace Elem Electrol 29, 119-126
Objective: Milk can provide more than 1/3 of the iodine content in human diet. Moreover, iodine supply in cow’s milk in Germany has improved throughout the last decade. Since 1982, analyses of iodine content of cow’s and human milk have been undertaken regularly in the State of Thuringia (East Germany). Data show increasing iodine concentration in milk over the past few years. Nonetheless, dietary supply of iodine via milk needs to be continuously monitored.
Material and methods: To investigate the latest trend of iodine content in milk over time, 135 samples of cow’s milk and 65 samples of human milk were analyzed by ICP-MS after digestion with tetra-methyl-ammonium hydroxide. Samples of cow’s milk (conventionally and organically produced) were purchased from the same supermarkets in Thuringia in March and November every year between 2007 and 2011. Human milk samples were obtained on a voluntary basis from breast-feeding women in Thuringia during the same time period.
Results: Samples of cow’s milk from 2007 to 2011 showed a mean iodine concentration of 122.0 ± 36.8 µg/l. There was no significant change during these 5 years (p > 0.05). In the same period, iodine content of conventionally produced milk was on average 51 µg/l higher compared to organically produced milk (p < 0.001). For all human milk samples, the mean iodine content was 170 ± 96 µg/l, with a range of 45.6 – 478.4 µg/l. In breast milk, not only were high variations present between samples of milk from the individual women, but iodine content also varied over lactation time.
Conclusions: The current results demonstrate that in East Germany the average iodine content in cow’s milk has remained stable at an appropriate level during the last 5 years. Although iodine concentrations in human milk likewise reveal relatively constant values on average, individual variations can be substantial.

S.A Johner, K. von Nida, G. Jahreis, T. Remer (2012) Aktuelle Untersuchungen zeitlicher Trends und saisonaler Effekte des Jodgehaltes in Kuhmilch - Untersuchungen aus Nordrhein Westfalen. Berliner und Münchner Tierärztliche Wochenschrift 125, Heft 1/2, 76-82
Milk is one of the most important iodine providers in the human diet. To investigate the longitudinal development of the iodine content of German cow’s milk, iodine content was analysed by a Cer-Arsenit method after alkaline wet washing in 112 milk samples from the greater Dortmund area (8 samples each were purchased in June and December from 2004 onward to 2010 in the same food markets). We found an increasing trend of milk iodine content until 2010 (P<0.005). The mean iodine content in 2004/05 was 97 ± 32 µg/L, in 2009/10 it was 110 ± 36 µg/L. This increase was only observable for conventionally produced milk samples (P=0.0003), and not for organic milk (P=0.6). The iodine content of summer milk was about 22 µg/L lower than that of winter milk (p<0,0001), however, seasonal variation was especially pronounced in organic milk. Iodine content of organic milk was in average about 54 µg/L lower than that of conventionally produced milk (P<0.0001). The moderate increase of milk iodine content to 110 µg/L on average contributes to the maintainence of the population’s iodine supply, whereas the analysed maximum iodine contents of around 160 µg/L do not give reason to expect an excessive iodine intake, even in case of a high milk consumption.

K. Kuhnt, C. Degen, A. Jaudszus, G. Jahreis (2012) Searching for health beneficial n-3 and n-6 fatty acids in plant seeds. Eur. J. Lipid Sci. Technol. 114, 153-160
Various plant seeds have received little attention in fatty acid research. Seeds from 30 species mainly of Boraginaceae and Primulaceae were analysed in order to identify potential new sources of the n-3 PUFA a-linolenic acid (ALA) and stearidonic acid (SDA) and of the n-6 PUFA g-linolenic acid (GLA). The fatty acid distribution differed enormously between genera of the same family. Echium species (Boraginaceae) contained the highest amount of total n-3 PUFA (47.1%), predominantly ALA (36.6%) and SDA (10.5%) combined with high GLA (10.2%). Further species of Boraginaceae rich in both SDA and GLA were Omphalodes linifolia (8.4, 17.2%, resp.), Cerinthe minor (7.5, 9.9%, resp.) and Buglossoides purpureocaerulea (6.1, 16.6%, resp.). Alkanna species belonging to Boraginaceae had comparable amounts of ALA (37.3%) and GLA (11.4%) like Echium but lower SDA contents (3.7%). Different genera of Primulaceae (Dodecatheon and Primula) had varying ALA (14.8, 28.8%, resp.) and GLA portions (4.1, 1.5%, resp.), but similar amounts of SDA (4.9, 4.5%, resp.). Cannabis sativa cultivars (Cannabaceae) were rich in linoleic acid (57.1%), but poor in SDA and GLA (0.8, 2.7%, resp.). In conclusion, several of the presented plant seeds contain considerable amounts of n-3 PUFA and GLA, which could be relevant for nutritional purposes due to their biological function as precursors for eicosanoid synthesis. Practical applications: N-3 PUFA are important for human health and nutrition. Unfortunately, due to the increasing world population, overfishing of the seas and generally low amounts of n-3 PUFA in major oil crops, there is a demand for new sources of n-3 PUFA. One approach involves searching for potential vegetable sources of n-3 PUFA; especially those rich in ALA and SDA. The conversion of ALA to SDA in humans is dependent on the rate-limiting D6-desaturation. Plant-derived SDA is therefore a promising precursor regarding the endogenous synthesis of n-3 long-chain PUFA in humans. The present study shows that, in addition to seed oil of Echium, other species of Boraginaceae (Cerinthe, Omphalodes, Lithospermum, Buglossoides) and Primulaceae (Dodecatheon, Primula), generally high in n-3 PUFA (30–50%), contain considerable amounts of SDA (5–10%). Therefore, these seed oils could be important for nutrition.

A. Roessler, S.D. Forssten, M. Glei, A.C. Ouwehand, G. Jahreis (2012).The effect of probiotics on faecal microbiota and genotoxic activity of faecal water in patients with atopic dermatitis: A randomized, placebo-controlled study. Clinical Nutrition 31, 22-29
Background: Colonic microbiota is involved in the etiology of colon cancer according to several reports. Studies also indicate that the microbiota differs between atopic patients and healthy subjects. Objective: To evaluate whether a probiotic mix containing Lactobacillus paracasei Lpc-37, Lactobacillus acidophilus 74-2, and Bifidobacterium animalis subsp. lactis DGCC 420 can affect the microbiota and its genotoxic activity in healthy subjects and patients with atopic dermatitis (AD). Methods: A placebo-controlled cross-over study was conducted. Fifteen healthy adults and 15 adult AD patients consumed 2 × 100 ml/d of either a probiotic or a placebo drink for 8 weeks followed by a wash out period of 2 weeks before crossing the intervention. Faecal water was isolated from stool samples collected at the end of each period. HT29c19a cells incubated with faecal water were measured for DNA damage using single-cell gel electrophoresis (“comet assay”). Bacterial species were determined by qPCR and concentrations of short-chain fatty acids were measured by means of gas chromatography. Results: Probiotic supplementation resulted in a significant increase in lactobacilli, whereas numbers of Bifidobacteria and Bacteroidetes remained unchanged. Clostridium perfringens cluster I–II was significantly reduced in healthy subjects. Genotoxic potential (expressed as tail intensity) of faecal water, was not affected. However, tail intensity decreased significantly in the probiotic period compared to placebo (23.5 vs. 16.7%) in AD patients. Although faecal concentrations of short-chain fatty acids were not affected, faecal pH was significantly reduced (7.0 vs. 6.6) in AD patients after probiotics. Conclusion. The results indicate that probiotics lower the genotoxic potential of faecal water in AD patients. The faecal C. perfringens cluster I–II levels remained unaffected suggesting either a change in their activity, or the fact that other bacterial species are responsible for the reduced genotoxic activity of faecal water.

2011

M. Köhler, A. Fechner, M. Leiterer, K. Spörl, T. Remer, U. Schäfer. G. Jahreis (2011) Iodine content in milk from German cows and in human milk: new monitoring study. Trace Elements and Electrolytes (Epub ahead of print]
Objective: Milk can provide more than 1/3 of the iodine content in human diet. Moreover, iodine supply in cow’s milk in Germany has improved throughout the last decade. Since 1982, analyses of iodine content of cow’s and human milk have been undertaken regularly in the State of Thuringia (East Germany). Data show increasing iodine concentration in milk over the past few years. Nonetheless, dietary supply of iodine via milk needs to be continuously monitored. Material and methods: To investigate the latest trend of iodine content in milk over time, 135 samples of cow’s milk and 65 samples of human milk were analyzed by ICP-MS after digestion with tetramethyl-ammonium hydroxide. Samples of cow’s milk (conventionally and organically produced) were purchased from the same supermarkets in Thuringia in March and November every year between 2007 and 2011. Human milk samples were obtained on a voluntary basis from breast-feeding women in Thuringia during the same time period. Results: Samples of cow’s milk from 2007 to 2011 showed a mean iodine concentration of 122.0 ± 36.8 μg/l. There was no significant change during these 5 years (p > 0.05). In the same period, iodine content of conventionally produced milk was on average 51 μg/l higher compared to organically produced milk (p < 0.01). For all human milk samples, the mean iodine content was 170 ± 96 μg/l, with a range of 45.6 – 478.4 μg/l. In breast milk, not only were high variations present between samples of milk from the individual women, but iodine content also varied over lactation time. Conclusions: The current results demonstrate that in East Germany the average iodine content in cow’s milk has remained stable at an appropriate level during the last 5 years. Although iodine concentrations in human milk likewise reveal relatively constant values on average, individual variations can be substantial.

Uta Enke, Anke Jaudszus, Ekkehard Schleussner, Lydia Seyfarth, Gerhard Jahreis, Katrin Kuhnt. Lipids in Health and Disease 2011, 10:247 (30 December 2011) Fatty acid distribution of cord and maternal blood in human pregnancy: special focus on individual trans fatty acids and conjugated linoleic acids
Background: Maternal nutrition in pregnancy has a crucial impact on the development of the fetus. Dietary trans fatty acids (tFA) are known to have adverse health effects, especially during pregnancy. However, the distribution of tFA produced via partial hydrogenation of vegetable oils (mainly elaidic acid; t9) differs compared to ruminant-derived tFA (mainly vaccenic acid; t11). Recent findings indicate that they may have different impact on human health. Therefore, in this study, plasma and erythrocytes of mother-child pairs (n = 55) were sampled to investigate the distribution of tFA, including individual trans C18:1 fatty acids and conjugated linoleic acids (CLA) in fetal related to maternal lipids; with additional consideration of maternal dairy fat intake.
Results: Portion of t9 and t11, but also of c9,t11 CLA was higher in maternal than in fetal blood lipids. The portion of t9 in maternal and fetal lipids differed only slightly. In contrast, the portion of fetal t11 was only half of that in maternal blood. This led to a fetal t9/t11-index in plasma and erythrocytes being twice as high compared to the maternal values. A high dairy fat intake resulted in elevated portions of t11 and its ∆9-desaturation product c9,t11 CLA in maternal blood. In contrast, in the respective fetal blood lipids only c9,t11 CLA, but not t11 was increased. Nevertheless, a positive association between maternal and fetal plasma exists for both t11 and c9,t11 CLA. Furthermore, in contrast to t9, t11 was not negatively associated with n-3 LC-PUFA in fetal blood lipids.
Conclusions: Fetal blood fatty acid composition essentially depends on and is altered by the maternal fatty acid supply. However, in addition to dietary factors, other aspects also contribute to the individual fatty acid distribution (oxidation, conversion, incorporation). The lower portion of fetal t11 compared to maternal t11, possibly results from ∆9-desaturation to c9,t11 CLA and/or oxidation. Based on the fatty acid distribution, it can be concluded that t11 differs from t9 regarding its metabolism and their impact on fetal LC-PUFA.

Ulrike Trautvetter, Bianka Ditscheid, Michael Kiehntopf, Gerhard Jahreis (2011) A combination of  calcium phosphate and probiotics beneficially influences intestinal lactobacilli and cholesterol metabolism in humans. Clin Nutr in press
Background & aims: The study focuses on the influence of a probiotic supplement alone and in combination with a calcium supplement on faecal lactobacilli colonisation and beneficial health effects such as a lowering of blood cholesterol.
Methods: Thirty-two men and women participated in the double-blind, placebo-controlled, cross-over study. All participants consumed a probiotic drink containing 1010 CFU/d Lactobacillus paracasei (LPC37) for four weeks. In addition, one group consumed bread enriched with pentacalcium hydroxytriphosphate (CaP; 1 g Ca/d) and the other group had bread without CaP. After a two-week washout and a two-week placebo period, the intervention was switched for further four weeks.
Results: After intervention with LPC37 + CaP, total cholesterol and LDL-cholesterol concentration in plasma decreased significantly compared to LPC37 and placebo. The faecal concentration of L. paracasei and that of all lactobacilli increased significantly after LPC37 + CaP and LPC37 compared to placebo. Moreover, secondary bile acids in faeces increased significantly after LPC37 + CaP intervention compared to placebo.
Conclusions: CaP modulates the colonisation of LPC37 in the human gut under combinatory supplementation of CaP and LPC37. The combined supplementation also decreases plasma LDL-cholesterol and the LDL/HDL ratio in healthy, moderately hypercholesterolemic men and women, which could be also due to the CaP supplementation. Clinical trial registration number: NCT01033461

Melanie Bähr, Gerhard Jahreis, Katrin Kuhnt (2011) Trans fatty acids in foods on the German market and in human tissue. Ernährungs-Umschau 58, 478–485
A high intake of trans fatty acids (TFA) is associated with adverse effects on health. Nevertheless, there is little current data on the TFA content in German foods. Therefore, the content and distribution of individual TFA were analysed in German foods (n = 229; 53 deep-fried potato products, 60 bakery products, 116 sweets) and in various human tissues (n = 162). TFA content varied greatly within all food categories (MIN 0 %, MAX 38 %), although the mean levels were less than in previous studies. Only 4 % of the deep-fried potato products, but 10 % of the sweets and as many as 48 % of the bakery products contained more than 2 % TFA within fat. There was an individual pattern of trans isomers in foods, depending on the origin of the fats used – particularly whether they were partially hydrogenated or from ruminants – and this was reflected in human tissues as well. In general, the average content of TFA in German foods is declining, but foods with high TFA and fat content are still available.

Degen C, Ecker J, Piegholdt S, Liebisch G, Schmitz G, Jahreis G. Metabolic and growth inhibitory effects of conjugated fatty acids in the cell line HT-29 with special regard to the conversion of t11,t13-CLA. Biochim Biophys Acta, Mol Cell Biol Lipids. 2011 Aug 26. [Epub ahead of print]
Conjugated fatty acids (CFAs) exhibit growth inhibitory effects on colon cancer in vitro and in vivo. To investigate whether the anticancerogenic potency depends on number or configuration of the conjugated double bonds, the effect of conjugated linoleic acid; (CLA; C18:2) isomers and conjugated linolenic acid (CLnA; C18:3) isomers on viability and growth of HT-29 cells were compared. Low concentrations of CLnAs (<10μM) yielded a higher degree of inhibitory effects compared to CLAs (40μM). All trans-CFAs were more effective compared to cis/trans-CFAs as follows: t9,t11,t13-CLnA≥c9,t11,t13-CLnA>t11,t13-CLA≥t9,t11-CLA>c9,t11-CLA. The mRNA expression analysis of important genes associated with fatty acid metabolism showed an absence of ∆5-/∆6-desaturases and elongases in HT-29 cells, which was confirmed by fatty acid analysis. Using time- and dose-dependent stimulation experiments several metabolites were determined. Low concentrations of all trans-CFAs (5-20μM) led to dose-dependent increase of conjugated t/t-C16:2 formed by β-oxidation of C18 CFAs, ranging from 1-5% of total FAME. Importantly, it was found that CLnA is converted to CLA and that CLA is inter-converted (t11,t13-CLA is metabolized to c9,t11-CLA) by HT-29 cells. In summary, our study shows that growth inhibition of human cancer cells is associated with a specific cellular transcriptomic and metabolic profile of fatty acid metabolism, which might contribute to the diversified ability of CFAs as anti-cancer compounds.

Katharina Domitila Petersen, Kim Karen Kleeberg, Gerhard Jahreis, Jan Fritsche. Assessment of the oxidative stability of conventional and high-oleic sunflower oil by means of solid-phase microextraction-gas chromatography. Int J Food Sci Nutr 2011, Early Online: 1–10
Headspace-solid-phase microextraction-gas chromatography (HS-SPME-GC) was used to identify in total 74 volatile lipid oxidation compounds altogether in thermally stressed conventional and high-oleic sunflower (HOSF) oil samples (in accelerated storage conditions for 14 days at 808C). Out of the volatile compounds identified, six volatile compounds were selected as marker compounds for the assessment of lipid oxidation of sunflower (SF) and HOSF oils due to their low odour threshold values and fatty-rancid odour impression. Additionally, other oxidation parameters such as fatty acid composition, peroxide value (PV), anisidine value and tocopherol and tocotrienol composition were determined. Multivariate statistical methods (principal component analysis and agglomerative hierarchical cluster analysis) were applied to identify sensitive oxidation marker compounds. Preliminary results revealed that hexanal, E-2-heptenal, E-2-decenal and E,E-2,4-nonadienal were the most suitable in differentiating HOSF and SF oil varieties from each other and SF samples with differing oxidative properties. Differentiation of SF samples according to their volatile compound composition was done in accordance with the results from the well-known oil quality parameters (e.g. PV or fatty acid composition). In conclusion, the combination of volatile compound analysis with HS-SPME-GC and multivariate statistical methods provides a sensitive tool in differentiating conventional SF and HOSF oils by means of volatile lipid oxidation marker compounds.

Knoll N, Kuhnt K, Kyallo FM, Kiage-Mokua BN, Jahreis G. High content of long-chain n-3 polyunsaturated fatty acids in red blood cells of Kenyan Maasai despite low dietary intake. Lipids Health Dis. 2011 Aug 19;10(1):141. [Epub ahead of print]
BACKGROUND: Increasing land restrictions and a reduced livestock-to-human ratio during the 20th century led the Maasai lead a more sedentary, market-orientated lifestyle. Although plant-derived food nowadays contributes substantially to their diet, dairy products being high in saturated fatty acids (SFA) and low in polyunsaturated fatty acids (PUFA) still are an important energy source. Since reliable data regarding the Maasai diet date back to the 1980s, the study objective was to document current diet practices in a Kenyan Maasai community and to investigate the fatty acid distribution in diet and red blood cells. METHODS: A cross-sectional study was conducted among 26 Maasai (20 women, 6 men) from Loodokilani, Kajiado District, Kenya. Food intake was described by the subjects via 24-h recall, and both food and blood samples were analysed. RESULTS: Two main foods - milk and ugali - constituted the Maasai diet in this region. A total of 0.9 L of milk and 0.6 kg of ugali were consumed per person to yield an energy intake of 7.6 MJ/d per person. A major proportion of ingested food contributing 58.3% to the total dietary energy (en%) was plant-derived, followed by dairy products representing 41.1 en%. Fat consumed (30.5 en%) was high in SFA (63.8%) and low in PUFA (9.2%). Long-chain n-3 PUFA (EPA, DPA and DHA) made up only 0.15% of the ingested fatty acids, but 5.9% of red blood cell fatty acids. CONCLUSION: The study indicates the Maasai diet is rich in SFA and low in PUFA. Nevertheless, red blood cells are composed of comparable proportions of long-chain n-3 PUFA to populations consuming higher amounts of this fatty acid group.

Degen C, Lochner A, Keller S, Kuhnt K, Dänicke S, Jahreis G (2011) Influence of in vitro supplementation with lipids from conventional and Alpine milk on fatty acid distribution and cell growth of HT-29 cells. Lipids Health Dis. 2011 Aug 4;10(1):131. [Epub ahead of print]
BACKGROUND: To date, the influence of milk and dairy products on carcinogenesis remains controversial. However, lipids of ruminant origin such as conjugated linoleic acids (CLA) are known to exhibit beneficial effects in vitro and in vivo. The aim of the present study was to determine the influence of milk lipids of different origin and varying quality presenting as free fatty acid (FFA) solutions on cellular fatty acid distribution cellular viability, and growth of human colon adenocarcinoma cells (HT-29). METHODS: FAME of conventional and Alpine milk lipids (MLcon, MLalp) and cells treated with FFA derivatives of milk lipids were analyzed by means of GC-FID and Ag+-HPLC. Cellular viability and growth of the cells were determined by means of CellTiter-Blue-assay and DAPI-assay (4',6-diamidino-2-phenylindole dihydrochloride), respectively. RESULTS: Supplementation with milk lipids significantly decreased viability and growth of HT-29 cells in a dose- and time-dependent manner. MLalp showed a lower SFA/MUFA ratio, a 8 fold increased CLA content, and different CLA profile compared to MLcon but did not demonstrate additional growth-inhibitory effects. In addition, total concentration and fatty acid distribution of cellular lipids were altered. In particular, treatment of the cells yielded highest amounts of two types of milk-specific major fatty acids (ug FA/mg cellular protein) after 8 h of incubation compared to 24 h; 200 uM of MLcon (C16:0, 206 +/-43), 200 uM of MLalp (C18:1 c9, (223 +/-19). Vaccenic acid (C18:1 t11) contained in milk lipids was converted to c9,t11-CLA in HT-29 cells. Notably, the ratio of t11,c13-CLA/t7,c9-CLA, an criterion for pasture feeding of the cows, was significantly changed after incubation for 8 h with lipids from MLalp (3.6 - 4.8), compared to lipids from MLcon (0.3 - 0.6). CONCLUSIONS: Natural lipids from conventional and Alpine milk showed similar growth inhibitory effects. However, different changes in cellular lipid composition suggested a milk lipid-depending influence on cell sensitivity. It is expected that similar changes may also be evident in other cell lines. To our knowledge, this is the first study showing a varied impact of complex milk lipids on fatty acid distribution in a colon cancer cell line.

Dawczynski C, Hackermeier U, Viehweger M, Stange R, Springer M, Jahreis G (2011) Incorporation of n-3 LC-PUFA and g-linolenic acid in blood lipids and red blood cell lipids together with their influence on disease activity in patients with chronic inflammatory arthritis - a randomized controlled human intervention trial. Lipids Health Dis. 2011 Aug 4;10(1):130. [Epub ahead of print]
BACKGROUND: Marine n-3 fatty acids and g-linolenic acid both have anti-inflammatory effects and may be useful to help treat inflammatory diseases. The effects of these alone or combined were examined in patients with arthritis in a randomized controlled trial. DESIGN: Patients with rheumatoid arthritis or psoriatic arthritis were randomized into four groups in a double-blind, placebo-controlled parallel designed study. Patients received the respective capsules (1: 3.0g n-3 LC-PUFA/d; 2: 3.2g g-linolenic acid/d; 3: 1.6g n-3 LC-PUFA + 1.8g g-linolenic acid/d; 4: 3.0g olive oil) for a twelve week period. Clinical status was evaluated and blood samples were taken at the beginning and at the end of the period. Differences before and after intervention were tested with paired t-test or with Wilcoxon test for non-normal data distribution. RESULTS: 60 patients (54 rheumatoid arthritis, 6 psoriatic arthritis) were randomised, 47 finished per protocol. In group 1, the ratio of arachidonic acid (AA)/eicosapentaenoic acid (EPA) decreased from 6.5 +/- 3.7 to 2.7 +/- 2.1 in plasma lipids and from 25.1 +/- 10.1 to 7.2 +/- 4.7 in erythrocyte membranes (p < 0.001). There was no significant influence on AA/EPA ratio due to interventions in group 2-4. In group 2, the intake of g-linolenic acid resulted in a strong rise of g-linolenic acid and dihomo-g-linolenic acid concentrations in plasma lipids, cholesteryl esters, and erythrocyte membranes. The combination of n-3 LC-PUFA and g-linolenic acid (group 3) led to an increase of g-linolenic acid and dihomo-g-linolenic acid concentrations in plasma lipids, cholesteryl esters, and erythrocyte membranes. This increase was only half of that in group 2. CONCLUSIONS: Incorporation of eicosanoid precursor FAs was influenced by an intake of n-3 LC-PUFA and g-linolenic acid suggesting a possible benefit for therapy of chronic inflammatory diseases. Trial Registration: ClinicalTrials NCT01179971.

Kuhnt Katrin, Baehr Melanie, Rohrer Carsten, Jahreis Gerhard (2011) Trans fatty acid isomers and the trans-9/trans-11 index in fat containing foods. Eur. J. Lipid Sci. Technol. 113, 1281–1292
To determine trans fatty acid (TFA) distribution of contemporary foods, especially regarding individual trans octadecenoic acids (trans C18:1), 339 German foods of six categories (semi-solid fats, deep-fried potato products, bakery products, confectioneries, instant products, and butter) were analysed using two GC methods. Results showed a high variation of TFA content between and within the categories containing between 0 to 40.5% of FAME except in butter, which is a source of natural TFA. The mean TFA values were below 2.0% of FAME, however, bakery products contained 4.5% and butter fat 3.2%, respectively. In addition, the distribution of individual trans C18:1 differed. In samples containing ruminant fat (butter and various confectioneries), vaccenic acid (t11-C18:1, t11) predominated, while in industrially processed foods, t9- and t10-C18:1 were the major trans isomers. This was reflected by a low t9/t11 index of 0.3 and 0.5 in butter and ruminant fat containing confectioneries, respectively, whilst the highest index was observed in shortenings and deep-fried potato products at 5.2 and 6.8, respectively. In conclusion, the TFA content of foods available on the German market is generally declining, but substantial variations are present. The t9/t11 index could be used as an indicator to determine ruminant fat.

Arnold, Christin; Jahreis, Gerhard (2011) Milk Fat and Health. Ernährungs-Umschau 58, 177-181
Although it is quite clear that the spectrum of nutrients in milk and milk products is unique, it is unclear whether the saturated fat in milk is unfavourable with respect to nutritional physiology. There is currently no convincing evidence that moderate ingestion of saturated fatty acids from milk increases the risk of cardiovascular diseases. It can be concluded that the effect of milk fat on human health cannot be generally described as unfavourable and that the biological function of each milk fatty acid should be considered separately.

Julia Pappritz; Ulrich Meyer; Ronny Kramer; Eva-Maria Weber; Gerhard Jahreis; Jürgen Rehage; Gerhard Flachowsky; Sven Dänicke (2011) Effects of long-term supplementation of dairy cow diets with rumen-protected conjugated linoleic acids (CLA) on performance, metabolic parameters and fatty acid profile in milk fat. Arch. Anim. Nutr. 65, 2011, 89-107
The supplementation of conjugated linoleic acids (CLA) to the rations of dairy cows represents an opportunity to reduce the content of milk fat. Therefore, CLA have the potential beneficial effect of reducing energy requirements of the early lactating cow. The present study aimed at the examination of long-term and post-treatment effects of dietary CLA intake on performance, variables of energy metabolism-like plasma levels of non-esterified fatty acids (NEFA) and -hydroxybutyrate (BHB), and fatty acid profile in milk fat. Forty-six pregnant German Holstein cows were assigned to one of three dietary treatments: (1) 100 g/d of control fat supplement (CON), (2) 50 g/d of control fat supplement and 50 g/d of CLA supplement (CLA-1) and (3) 100 g/d of CLA supplement (CLA-2). The lipid-encapsulated CLA supplement consisted of approximately 10% of trans-10, cis-12 CLA and cis-9, trans-11 CLA each. The experiment started 1 d after calving and continued for about 38 weeks, divided into a supplementation (26 weeks) and a depletion period (12 weeks). Over the first 7 weeks of treatment, 11 and 16% reductions in dry matter intake compared to control were observed for the cows fed CLA-1 and CLA-2 supplements respectively. Consequently, the calculated energy balance for these two CLA groups was lower compared to the control. Plasma levels of NEFA and BHB remained unaffected. Later in lactation the highest CLA supplementation resulted in a reduction of milk fat content of 0.7%. However, no reduction in milk fat yield, and accordingly no milk fat depression (MFD), could be shown. The trans-10, cis-12 CLA in milk fat increased with increasing dietary CLA supplementation in a dose-dependent manner. The proportion of C16 in milk fat was decreased by the highest CLA supplementation. With the exception of an increase in plasma glucose level in the CLA-2 group, no post-treatment effects were observed. Overall, under the conditions of the present study no improvement in the calculated energy balance by CLA supplementation could be shown for the entire evaluation period.

Steffen Wohlgemuth, Sylvia Keller, Romy Kertscher, Mandy Stadion, Dirk Haller, Sigrid Kisling, Gerhard Jahreis, Michael Blaut, Gunnar Loh (2011) Intestinal steroid profiles and microbiota composition in colitic mice. Gut Microbes 2:3, 159-166
Reduced gut microbiota diversity in conjunction with a bloom of a few bacterial species is a common feature in inflammatory bowel disease (IBD) patients. However, the environmental changes caused by inflammation and their possible impact on the microbiota are largely unknown. Since IBD is associated with an impaired intestinal steroid metabolism, we hypothesized that changes in intestinal steroid and particularly bile acid (Ba) concentrations affect microbial communities. We used Interleukin-10 deficient (IL-10 -/- ) mice as a model for chronic gut inflammation. Healthy wild-type mice served as controls. In these animals, intestinal steroid concentrations and gut microbial diversity were analyzed at 24 weeks of age. The IL-10 -/- mice developed moderate inflammation in cecum and colon and colorectal tumor formation was observed in 55% of the animals. Compared to the healthy conditions, gut inflammation was associated with higher intestinal cholesterol and cholic acid concentrations and a reduced microbial diversity. The latter was accompanied by a proliferation of Robinsoniella peoriensis, Clostridium innocuum, Escherichia coli and Enterococcus gallinarum. All these species proved to be highly bile acid resistant. We concluded that chronic colitis in IL-10 -/- mice is associated with changes in intestinal steroid profiles. These changes may be due to alterations in gut microbiota composition or vice versa. Whether the bacterial sterol and bile acid metabolism is implicated in colitis and colorectal carcinoma etiology remains to be clarified.

Keller S, Prechtl D, Aslanidis C, Ceglarek U, Thiery J, Schmitz G, Jahreis G (2011) Increased plasma plant sterol concentrations and a heterozygous amino acid exchange in ATP binding cassette transporter ABCG5: A case report. Eur J Med Genet. 54(4):e458-60. Epub 2011 May 23.
Whilst conducting a scientific study, an elevated plasma plant sterol concentration of 3.07 mg/dL was established in one proband. Similar levels found in his mother’s plasma (2.73 mg/dL) were suggestive of a heterozygous sitosterolemia. The resulting gene analysis for ATP binding cassette transporter G5/G8 (ABCG5/G8) revealed a heterozygous polymorphism in ABCG8 (Thr400Lys, rs4148217), which the proband had inherited from his father. However, a heterozygous amino acid exchange (Arg406Gln) in exon 9 of ABCG5 was revealed, which was inherited from his mother. Although not sufficient evidence exists to regard this sequence variation as a mutation, this previously unreleased sequence variation occurred in a "hot spot" area for sitosterolemia of the ABCG5 gene (exon 9) and the similar increased plasma plant sterol concentrations of the heterozygous mother contribute to the notion, that this very likely presents an inactivating mutation.

Jahreis, G, Schäfer, U. (2011). Rapeseed (Brassica napus) oil and its benefits for human health. In V. R. Preedy, R. R. Watson, V. B. Patel (Editors), Nuts & Seeds in Health and Disease Prevention (1st ed.) London, Burlington, San Diego, Academic Press/Elsevier (pp 967-974)
Rapeseed oils for human nutrition are offered as a refined edible oil with 00-quality, as a cold-pressed edible oil, and as HOLLi quality oil (very low a-linolenic acid of 3%). Refined and cold-pressed rapeseed oils are valuable because of their high a-linolenic acid content (about 10%), their low saturated fatty acid content (6%), and their optimal n-6 :n-3 ratio (2:1).
In humans, a-linolenic acid is converted to eicosapentaenoic acid and docosahexaenoic acid; these two fatty acids are therefore not essential. The conversion efficiency of a-linolenic acid to long-chain n-3 PUFAs, important precursors of anti-inflammatory eicosanoids, is limited. High dietary intake of n-6 PUFA impairs the conversion rate.
According to several studies, consumption of n-3 PUFA is positively correlated with cardiovascular and neuropsychiatric health effects, and results in a lower ratio of arachidonic acid/eicosapentaenoic acid in human cell membranes. These data support the health-beneficial effects of rapeseed oil.

Dawczynski, Christine and Jahreis Gerhard (2011), Benefits of Fish Oil for Rheumatoid Arthritis, In: Debasis Bagchi, Hiroyoshi Moriyama, Siba P. Raychaudhuri (Eds.) Arthritis: Pathophysiology, Prevention, and Therapeutics, CRC Press/Taylor & Francis, USA, pp. 349–384,

1  Chemical structure of n-3 PUFA

2  Anti-inflammatory effects of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA)
   2.1  Effects on eicosanoid metabolism
   2.2  Effects on gene expression
   2.3  Effects on production of cytokines
   2.4  Effects on the production of ‘pro-resolving’ mediators (resolvins, protectins, maresins)
   2.5  Effects on bone metabolism and cartilage integrity

3  Effects of fish oil-derived n-3 LC-PUFA on therapy of RA (human intervention trials)
   3.1  Limitations of human intervention studies with n-3 PUFA in RA patients
   3.2  Effect of fish oil on inflammation parameters depend on genotype

4  Effects of n-3 LC-PUFA on the risk for coronary heart diseases (CHD)

5  References

Fechner, A., Schweiggert, U., Hasenkopf, K., Jahreis, G.. (2011). Lupine kernel fiber: Metabolic effects in human intervention studies and use as a supplement in wheat bread. In V. R. Preedy, R. R. Watson, & V. B. Patel, (Eds.), Flour and breads and their fortification in health and disease prevention (pp. 463-473). London, Burlington, San Diego: Academic Press, Elsevier.
Due to its neutral taste, mouthfeel, and white color, lupine kernel fiber can be incorporated in high amounts into foods without impairing the sensory profile. Lupine kernel fiber can be obtained by extracting proteins and other water-soluble substances from the dehulled and deoiled kernels. Lupine kernel fiber decreases plasma cholesterol, triacylglyceroles, and C-reactive protein in moderate hypercholesterolemic subjects, but the mechanisms are not fully understood. Legumes affect hypertension, diabetes, and obesity. These factors can independently contribute to the cardiovascular protective effects of foods enriched with lupine fiber. Lupine kernel fiber has a beneficial impact on the function of the colon and on general health. Lupine kernel fiber has a positive impact on the putative risk factors of colon cancer.

2010

Jahreis Gerhard, Hengst Christin: Fat-modified dairy products and blood lipids in humans. In: F. De Meester et al. (eds.) Modern Dietary Fat Intake in Disease Promotion. Humana Press, c/o Springer New York Dordrecht Heidelberg London, (2010) 205 – 214
Dairy products are an important part of a healthy human diet due to its highly nutritional value. However, with regard to its relatively high content of saturated fatty acids (SFA), milk fat has been considered to contribute to a hypercholesterolaemic state. On the other hand, there is some indication that other milk fatty acid classes are associated with hypocholesterolaemic effects. Therefore, positive as well as negative properties of dairy products are discussed. As a result, scientific interest has been arisen to enhance the health benefits through modifying the milk fat composition. First human intervention studies suggest that fat-modified milk products provide positive effects on established risk factors of cardiovascular diseases (CVD) like dyslipidemia, hypertension and obesity. Prospectively, fat-modified dairy products may play a role in the primary prevention of cardiovascular diseases (CVD). This chapter attempts to contrast known effects of milk lipids on blood lipid profiles (as a risk factor) with respect to CVD.

Jaudszus Anke, Kuhnt Katrin, Rohrer Carsten, Jahreis Gerhard: CLA TAG rich in cis-9,trans-11-CLA is stable beyond 2 years of proper storage. Eur J Lipid Sci Technol 112 (2010) 1393–1639
We analyzed a triacylgylcerol esterified CLA preparation characteristically rich in c9,t11-CLA and free of t10,c12-CLA three times within a period of 2½ years by GC and silver ion- HPLC. For the first time, we present data on the long-term stability of this preparation with regard to the fatty acid profile and the isomeric composition of CLA under certain storage conditions, providing useful information for the planning of long-term trials.

Anke Jaudszus, Peter Moeckel, Eckard Hamelmann, Gerhard Jahreis: Trans -10, cis -12-CLA-Caused Lipodystrophy Is Associated with Profound Changes of Fatty Acid Profiles of Liver, White Adipose Tissue and Erythrocytes in Mice: Possible Link to Tissue-Specific Alterations of Fatty Acid Desaturation. Ann Nutr Metab 2010;57:103–111
Dietary supplementation with conjugated linoleic acid (CLA) has been shown to reduce body fat mass. To investigate the effects of individual CLA isomers on the fatty acid profiles of lipogenic (liver and white adipose) and lipid sensitive (erythrocyte) tissues, BALB/c mice were fed with 1 of 2 diets supplemented with either a c 9, t 11-CLA-enriched and t 10, c 12-CLAfree or a CLA-mixture containing both isomers in equal amounts (1% w/w of the diet) for 5 weeks. A control group was fed with a diet enriched in sunflower oil to energy balance the CLA. Compared to the t 10, c 12-CLA-free and the control diets, we observed a significant reduction of adipose tissue accompanied by fatty livers in the CLA-mix-fed group. These alterations in body fat distribution entailed a conspicuous shift of the fatty acid profiles of adipose tissue and livers. Liver enlargement was mainly caused by accumulation of C18 monoenes that accounted for 67 8 1% of total fatty acid methyl esters. The significant reduction of the 18: 0/18: 1 desaturation index in the liver upon CLA-mix diet indicated high stearoyl-CoA desaturase activity. In contrast, reduction in white adipose tissue was largely driven by percental reduction of monounsaturated fatty acids (p ^ 0.001). 16: 0/ 16: 1 and 18: 0/18: 1 desaturation indices for white adipose tissue significantly increased, suggesting an inhibition of stearoyl-CoA desaturase upon CLA-mix diet. The fatty acid profile of the erythrocytes widely reflected that of livers, depending on the supplemented diet. These profound changes in fatty acid composition of lipogenic organs due to t 10, c 12-CLA intake may be the consequence of functional alterations of lipid metabolism.

Dawczynski Christine,  Martin Lena, Wagner Andreas, Jahreis Gerhard: n-3 LC-PUFA-enriched dairy products are able to reduce cardiovascular risk factors: A double-blind, cross-over study. Clin. Nutr. 29 (2010) 592-599.
Background & aims: The effects of n-3 LC-PUFA-supplemented dairy products on cardiovascular risk factors in mildly hypertriacylglycerolemic patients (TAG: <1.5 mmol/L) were determined.
Methods: Fifty-one patients (25 f, 26 m) were included in the double-blind, placebo-controlled cross-over study and were randomly divided into two groups. Both groups received intervention (3 g n-3 LC-PUFA/d) and control dairy products consecutively for fi fteen weeks with a ten-week wash-out phase between the two treatments. Blood samples and 24-h urine were obtained at the beginning and at the end of each period. The blood lipids were determined by enzymatic methods and using the autoanalyser Synchron LX systems (Beckman Coulter). 7,8-Dihydro-8-oxo-20-deoxyguanosine and fatty acids were analysed with HPLC and GC.
Results: Generally, the consumption of the intervention products resulted in a significant improvement of cardiovascular risk factors, e.g., n-3 FA index, AA/EPA ratio, total cholesterol, and TAG. The TAG and LDL/HDL ratio were lower at the end of the intervention period in comparison with the control period, whereas HDL cholesterol was higher at the end of the intervention period. Further, n-3 LC-PUFA-enriched products did not cause additional oxidative DNA damage as shown by the 7,8-dihydro-8-oxo-20-deoxyguanosine excretion.
Conclusions: The consumption of n-3 LC-PUFA-supplemented dairy products decreases cardiovascular risk factors.

Fechner Anita, Jahreis Gerhard: Lupine kernel fibre can help to manage risk factors for atherosclerosis. Atherosclerosis Suppl. 11, 2 (2010) 150 (Abstr.)
There is evidence that the consumption of legume kernel fibre, containing both soluble and insoluble fibre fractions, may beneficially modify coronary and colonic health. Therefore, the objective of two human intervention studies was to determine the efficacy of a native lupine kernel fibre (L. angustifolius Boregine) on the prevention of risk factors for gastrointestinal or cardiovascular diseases. In study I 26 healthy subjects consumed the pure lupine fibre- product (25 g/day) over two weeks. In study II 54 moderate hypercholesterolemic subjects consumed the same amount, incorporated in different food, over a period of 28 days.
The serum cholesterol concentration did not change in normocholesterolemic subjects. In contrast, the four-week intervention with lupine fibre-enriched food in hypercholesterolemic subjects decreased the total cholesterol by 12% (P<0.001) compared to baseline. The LDL concentration was lowered by 15% (P<0.001) and HDL cholesterol remained unchanged. Moreover, the lupine fibre enriched diet led to a significant decrease of the triacylglyceroles (P=0.03) and of the high sensitivity C-reactive protein (P=0.02).
Additionally, the intake of lupine fibre increased satiety and modified nutritional behaviour positively (lower intake of energy, fat, protein and cholesterol), which can support long- term weight loss and protect against diet-induced obesity.
To sum up, the results of the present studies show that lupine kernel fibre can have a positive impact on putative risk factors of atherosclerosis. The inclusion of this palatable lupine fibre into the diet can help predisposed people in prevention of coronary heart disease and the fibre-consumption can support medical therapies.

Annegret Auinger, Ulf Helwig, Diana Rubin, Julia Herrmann, Gerhard Jahreis, Maria Pfeuffer, Michael de Vrese, Ulrich Robert Foelsch, Stefan Schreiber, Frank Doering, Juergen Schrezenmeir. Human intestinal fatty acid binding protein 2 expression is associated with fat intake and polymorphisms. J. Nutr. 140 (2010)   1411-1417
The intestinal fatty acid binding protein (FABP2) is involved in lipid metabolism whereby variations in the promoter (haplotypes NB) and exon 2 (Ala54Thr) are associated with dyslipidemia and insulin resistance. To elucidate which factors determine FABP2 expression in human mucosa, we investigated the association between fat intake, genotypes, biochemical variables, and FABP2 expression. FABP2 gene expression was assessed in duodenal specimens from 100 participants who answered a FFQ and who were genotyped and characterized for traits of metabolic syndrome and further biochemical data. Homozygotes for haplotype A tended to have lower fat intake than B-allele carriers (P = 0.066). Searching for an explanation, we evaluated the orexigenic glucose-dependent insulinotropic polypeptide (GIP) in a subset from the Metabolic Intervention Cohort Kiel. AA homozygotes had lower postprandial GIP concentrations than BB homozygotes. Duodenal FABP2 expression was correlated with (n-3) fatty acid (FA) intake in AA homozygotes (r = 0.49; P = 0.021). It was higher in AA homozygotes than in B-allele carriers after adjustment for (n-3) FA intake (P = 0.049) and was negatively correlated with serum FFA (r = -0.41; P < 0.01). Our data indicate that FABP2 expression depends on (n-3) FA intake and FABP2 genotypes. FABP2 might be involved in regulating food intake and intestinal FA utilization.

Hartung D, Stadeler M, Grieshaber R, Keller S, Jahreis G.Work and diet-related risk factors of cardiovascular diseases: comparison of two occupational groups. J Occup Med Toxicol. 2010 Mar 22;5:4.
BACKGROUND: Although work related risk factors associated with Cardiovascular Diseases (CD) have been well researched, there is no detailed knowledge regarding disparate occupational groups each with a different risk exposition. Therefore, two occupational groups (chefs and office workers) were compared with a focus on nutritional and psychosocial factors.
METHODS: Two groups of subjects were tested for work and diet-related risks of CD (45 chefs and 48 office workers). The groups matched both for gender (male) and age (30 to 45 years). The study included a medical check-up, bioelectrical impedance analysis as well as an evaluation of questionnaires on health, nutritional behaviour and coping capacity. In addition, volunteers were required to compile a 7-day-dietary-record and collect their urine 24 h prior to their check-up. Blood samples drawn were analysed for glucose and lipid metabolism, homocysteine, vitamin B12, folic acid; C-reactive protein, uric acid, red blood cell fatty acids, plant sterols, antioxidative capacity and oxidative stress.
RESULTS: On average, the chefs showed one risk factor more compared to the office workers. The most frequent risk factors in both groups included overweight/obesity (chef group [CG]: 62.2%; office group [OG]: 58.3%) and elevated TC (CG: 62.2%; OG: 43.8%]. Moreover, although the chefs often had higher CRP-concentrations (40.0%), more office workers suffered from hypertension (37.5%).Chefs showed significant higher concentrations of saturated fatty acids and oleic acid, whereas docosahexaenoic acid, Omega-6- and trans fatty acids were found more frequently in the red blood cell membranes of office workers. While there were no significant differences in analysed plant sterols between the two occupational groups, 7,8-dihydro-8-oxo-2'-deoxyguanosine was significantly increased in office workers.Concerning the work-related psychosocial factors, the chefs were characterised by a stronger subjective importance of work, a greater degree of professional aspiration and enhanced efforts at perfectionism at their workplace.
CONCLUSIONS: The chefs in the study bear a higher risk of CD compared to the office-workers. Although, CD is not exclusively a result of workplace-conditions, study results show that work-related influences can not be ignored. Thus, prevention of CD may be an important task attributable to occupational physicians.

Katrin Kuhnt, Christian Degen, Gerhard Jahreis. 2-Propanol in the mobile phase reduces the time of analysis of CLA isomers by silver ion-HPLC. J Chromatogr B, 878 (2010) 88–91
Individual isomers of octadecadienoic acid (C18:2) with conjugated double bonds (conjugated linoleic acids; CLA) exert different biological activities. Their distribution in food and tissues differs. Therefore, the separation of the various positional and geometric isomers is important. The time of analysis using silver ion-high performance liquid chromatography can extend up to 90 min. The aim of this study was to reduce this time. The time of analysis reduced from ca. 90 min onto 45 to 35 min, respectively, by the addition of 0.05% or 0.1% (v/v) 2-propanol to the mobile phase [acetonitrile (0.1%; v/v) and diethyl ether (0.5%; v/v) in n-hexane]. There was no effect on resolution of the 17 individual CLA isomers of the CLA mixture. Regarding the lowest coefficient of variation and an adequate baseline separation the use of 0.05% 2-propanol in the mobile phase is recommended, without any disadvantages and adverse effects on the service life of columns. In conclusion, adding 0.05% or 0.1% 2-propanol to the mobile phase shortens the time of analysis of CLA isomers, saves solvents and reduces costs.

S Keller. Faecal varieties between high- and low-converters of cholesterol. European Journal of Clinical Nutrition (2010) 64, 227–229
Background: Analyzing faecal sterol concentrations in humans, subjects with a strongly decreased faecal cholesterol conversion were identified. The reasons and outcomes of this phenomenon have not been sufficiently investigated because of the complexity of the host–microflora interactions.
Subjects/Methods: To evaluate differences between cholesterol high and low converters, the sterol excretion and faeces attributes of 320 healthy subjects (213 women, 107 men) were analyzed. Two different cut-off levels classifying cholesterol high and low converters were tested (level 1: conversion rate <30%; level 2: 50th percentile).
Results: In both test models the faeces attributes differ significantly in a lower pH value and a lower faecal dry matter of the low converters in comparison with the high converters.
Conclusions: These findings in faeces may reflect the conditions in the colon and can be a reason for the decreased bacterial growth and/or activity of cholesterol-reducing bacteria in the colonic microflora.

2009

Dawczynski C, Schubert R, Hein G, Müller A, Eidner T, Vogelsang H, Basu S, Jahreis G. Long-term moderate intervention with n-3 long-chain PUFA-supplemented dairy products: effects on pathophysiological biomarkers in patients with rheumatoid arthritis. Br J Nutr. 2009, 101, 1517-1526
n-3 long-chain PUFA (n-3 LC-PUFA) may improve cardiovascular and inflammatory diseases. The effects of n-3 LC-PUFA-supplemented dairy products on inflammation and immunological parameters, biomarkers of oxidative stress, serum lipids, and on disease activity were determined in patients with rheumatoid arthritis (RA). Forty-five subjects (forty-three females and two males) were randomly divided into two groups in a double-blind, placebo-controlled cross-over study. Both groups received placebo or verum products consecutively for 3 months with a 2-month washout phase between the two periods. Blood samples were taken at the beginning and at the end of each period. The dairy products generally improved serum lipids by increasing HDL and lowering lipoprotein a. The n-3 LC-PUFA supplements act to lower TAG. Additionally, a decreased lipopolysaccharide-stimulated cylo-oxygenase-2 expression was found in patients who had consumed the enriched dairy products. The majority of the CD analysed were not influenced, although n-3 LC-PUFA did suppress the immune response as lymphocytes and monocytes were found to be significantly decreased. The n-3 LC-PUFA did not increase the biomarkers of oxidative stress such as 8-iso-PGF2alpha and 15-keto-dihydro PGF2alpha, and DNA damage like 7,8-dihydro-8-oxo-2'-deoxyguanosine. The long-term consumption of dairy products (2 x 12 weeks) diminished the excretion of hydroxypyridinium crosslinks, and favoured the diastolic blood pressure. The consumption of moderate doses of n-3 LC-PUFA in combination with dairy products did not improve the disease activity. However, there is evidence of cardioprotective effects. Furthermore, the long-term consumption of dairy products acts against the cartilage and bone destruction in RA.

Dawczynski C, Jahreis G. Prevention of Cardiovascular Diseases with Milk Products Supplemented with Long-Chain Omega-3-Fatty Acids. Ernährungs Umschau 2009, 56, 618–625
In two interventional studies in man, the influence of the consumption of n-3-LC-PUFA-enriched yoghurt was examined on cardiovascular risk factors (blood lipids). The volunteers consumed the intervention products with 0.8 g n-3-LC-PUFA/125 g yoghurt or comparator products for a period of 5 or 10 weeks. Blood samples were taken at the start and end of each phase. As a consequence of the 5-week consumption of the enriched products, HDL-cholesterol was significantly increased and the LDL/HDL quotient was reduced. After 10 weeks, these effects were more marked in the group given 0.8 g n-3-LC-PUFA/125 g yoghurt. The favourable changes in HDL-cholesterol and in the LDL/HDL quotient were not found in subjects given low fat (less enriched) yoghurt over a period of 10 weeks. There was a trend for TAG to be reduced in this group (p = ? 0.1). Conclusion: Daily consumption of n-3-LC-PUFA-enriched yoghurt (0.8 g n-3-LC-PUFA/125 g yoghurt) had a favourable effect on cardiovascular risk factors.

Ditscheid B, Keller S, Jahreis G. Faecal steroid excretion in humans is affected by calcium supplementation and shows gender-specific differences. Eur J Nutr 48, 22-30, 2009
BACKGROUND: Previous human studies on the effect of dietary calcium supplementation on faecal excretion of bile acids (BA) and faecal water concentrations of animal neutral sterols (NSt, cholesterol and its metabolites) lack detailed information about single BA and NSt.
AIM OF THE STUDY: We investigated whether single BA and NSt in faeces and especially in faecal water are affected by calcium supplementation and whether this affects genotoxicity of faecal water. In addition, we differentiated between men and women with regard to the concentrations of BA and NSt in faecal water.
METHODS: Thirty-one healthy volunteers consumed a calcium supplemented bread (1.0 g/day) and a placebo bread, respectively, for 4 weeks in a double-blind, randomised cross-over trial. Faeces were collected quantitatively for 5 days in the last week of each period. NSt and BA were analysed by GC-MS.
RESULTS: Due to calcium supplementation faecal concentrations of lithocholic acid (LCA, 14%, P = 0.008), deoxycholic acid (DCA, 19%, P < 0.001) and 12 keto-deoxycholic acid (12 keto DCA, 29%, P = 0.049) significantly increased whereas BA concentrations in faecal water were only marginally affected. In contrast, concentrations of cholesterol (30%, P = 0.020) and its metabolites coprostanol (43%, P = 0.004), coprostanone (36%, P = 0.003), cholestanol (44%, P = 0.001) and cholestenone (32%, P = 0.038) in faecal water significantly decreased. Total NSt concentration in faecal water was found to be significantly higher in women compared to men (P = 0.018). The genotoxicity of faecal water was neither affected by calcium supplementation nor were there gender-specific differences.
CONCLUSIONS: Dietary calcium supplementation diversely affects BA and NSt in faeces and in faecal water but does not influence the genotoxicity of faecal water in healthy adults.

Foekel C, Schubert R, Kaatz M, Schmidt I, Bauer A, Hipler U-Ch, Vogelsang H, Rabe K, Jahreis G. Dietetic effects of oral intervention with mare's milk on SCORAD, faecal microbiota and immunological parameters in patients with atopic dermatitis. Internat J Food Sci Nutr, 2009 [online on InformaWorld]
In a double-blind, placebo-controlled crossover trial 23 patients consumed 250 ml mare's milk or placebo for 16 weeks. The aim was to examine the effects of mare's milk on characteristics of atopic dermatitis (AD), on faecal microbiota and on clinical and immunological parameters. The intensity of AD was examined using the Severity Scoring of Atopic Dermatitis (SCORAD) index. During the mare's milk period the mean SCORAD of patients (n = 23; 17 females, 6 males) decreased from 30.1 to 25.3 after 12 weeks (P < 0.05) and to 26.7 after 16 weeks (P < 0.1). In a subgroup (n = 7) the SCORAD and especially the pruritus decreased by 30% through the mare's milk period (P < 0.01). In this subgroup the faecal Bifidobacteria increased during the mare's milk period from 4.6 to 11.9% of Eubacteria (P < 0.05). The immunological parameters, except C-reactive protein (CRP) were unchanged.

Grün M, Liebisch M, Sauerwein H , Jahreis G, Sachse K. Flow cytometric quantification of chlamydial infection in cell culture. J Microbiol Methods 78 (2009) 360–362.
A flow cytometric method was developed, which allows fast and efficient analysis of cell cultures infected with chlamydiae. The proportion of positive cells increased with the infectious dose and correlated with chlamydia copy numbers calculated from real-time PCR. While retaining the advantages of single- cell analysis, flow cytometry allows handling of large sample numbers and counterstaining for additional marker proteins.

Helbig D, Wagner A, Schubert R. Jahreis G. Tocopherol isomer pattern in serum and stool of human following consumption of black currant seed press residue administered in whole grain bread. Clin Nutr. 2009, 28, 662 -667
Background and aims. Serum γ-tocopherol is thought to be associated with human health. The dietary influence of tocopherol and fibre-rich black currant seed press residue on serum and stool tocopherol concentration was investigated in a controlled human intervention study.
Methods. Thirty-six women consumed bread enriched with black currant press residue (4 weeks). The resultant faecal and serum tocopherol concentrations were compared with those after a period consuming control bread without press residue and a normal baseline diet. Fibre intake and excretion, antioxidant capacity (TEAC), and vitamin C concentrations in serum and urine were also determined. Samples were obtained with a 5-day standardised diet at the end of each period.
Results. The press residue bread lead to significantly increased β-, γ-, δ- and total tocopherol intake, serum α-, β-, γ- and total tocopherol concentration (with and without lipid adjustment), fibre intake and urinary vitamin C concentration compared to control bread (P < 0.05). Faecal excretion of total tocopherols and fibre increased compared to baseline (P < 0.05).
Conclusions. Fibre intake and excretion influence total tocopherol concentration in lipid-adjusted serum and in stool. The outstandingly high increase of serum γ-tocopherol concentration through seed press residue consumption could be due to a presumed interruption of the enzymatic tocopherol degradation mechanism by bread constituents.

Helbig D, Wagner A, Glei M, Basu S, Schubert R, Jahreis G. Blackcurrant seed press residue increases tocopherol concentrations in serum and stool whilst biomarkers in stool and urine indicate increased oxidative stress in human subjects. Br J Nutr. 2009, 102, 554-562
Berry seeds are a tocopherol-rich by-product of fruit processing without specific commercial value. In a human intervention study, the physiological impact of blackcurrant seed press residue (PR) was tested. Thirty-six women (aged 24 +/- 3 years; twenty non-smokers, sixteen smokers) consumed 250 g bread/d containing 8 % PR for a period of 4 weeks (period 3). Comparatively, a control bread without PR (250 g/d) was tested (period 2) and baseline data were obtained (period 1). Blood, stool and 24 h urine were collected during a 5 d standardised diet within each period. Tocopherol and Fe intakes were calculated from food intake. In serum, tocopherol concentration and Fe parameters were determined. In urine, oxidative stress markers 8-oxo-2'-deoxyguanosine, 8-iso-PGF2alpha and inflammatory response marker 15-keto-dihydro-PGF2alpha were analysed. Stool tocopherol concentration, genotoxicity of faecal water (comet assay) and antioxidant capacity of stool (aromatic hydroxylation of salicylic acid) were determined. Fe and total tocopherol intake, total tocopherol concentrations in serum and stool, and genotoxicity of faecal water increased with PR bread consumption (P < 0.05). The antioxidant capacity of stool decreased between baseline and intervention, expressed by increased formation of 2,3- and 2,5-dihydroxybenzoic acid in vitro (P < 0.05). In smokers, 8-oxo-2'-deoxyguanosine increased with PR consumption (P < 0.05). Prostane concentrations were unaffected by PR bread consumption. In summary, the intake of bread containing blackcurrant PR for 4 weeks increased serum and stool total tocopherol concentrations. However, various biomarkers indicated increased oxidative stress, suggesting that consumption of ground berry seed may not be of advantage.

Hengst Ch, Ptok S, Roessler A, Fechner A, Jahreis G: Effects of polydextrose supplementation on different faecal parameters in healthy volunteers. Int J Food Sci Nutr 2009, 60, 96-105
Polydextrose (PDX) is a non-digestible polysaccharide providing beneficial effects on bowel health. The aim of the study was to show prebiotic effects of PDX. A placebo-controlled, randomized intervention study with PDX supplementation (8 g/day) was conducted in 45 healthy subjects. The effects of PDX on stool weight, orofaecal transit time, consistency of stool (Bristol stool form scale), short-chain fatty acid production, pH value, neutral sterol and bile acid excretion and faecal microbiota were evaluated. It was found that supplementation of PDX shortened the orofaecal transit time significantly. Furthermore, ingestion of PDX resulted in a decreased pH value and in significant changes in bile acid and neutral sterol excretion. PDX had no effects on stool weight, concentrations of the abundant short-chain fatty acids (acetate, propionate) and faecal contents of Lactobacillus acidophilus and Bifidobacterium lactis. In conclusion, PDX is able to shorten the orofaecal transit time and to improve stool consistency in subjects suffering from constipation.

Keller S. Faecal varieties between high- and low-converters of cholesterol European Journal of Clinical Nutrition advance online publication, 2009, 1-3
Background: Analyzing faecal sterol concentrations in humans, subjects with a strongly decreased faecal cholesterol conversion were identified. The reasons and outcomes of this phenomenon have not been sufficiently investigated because of the complexity of the host–microflora interactions. Subjects/Methods: To evaluate differences between cholesterol high and low converters, the sterol excretion and faeces attributes of 320 healthy subjects (213 women, 107 men) were analyzed. Two different cut-off levels classifying cholesterol high and low converters were tested (level 1: conversion rate o30%; level 2: 50th percentile). Results: In both test models the faeces attributes differ significantly in a lower pH value and a lower faecal dry matter of the low converters in comparison with the high converters. Conclusions: These findings in faeces may reflect the conditions in the colon and can be a reason for the decreased bacterial growth and/or activity of cholesterol-reducing bacteria in the colonic microflora.

Kuhnt K, Flotho S, Benjamin S, Boerchers T, Schubert R, Jahreis G, Spener, F. Gene expression after dietary intervention with trans fatty acids (trans-11/trans-12 18:1) in humans Eu J Lipid Sci Techn 111 (2009), 442-450
Gene-by-diet interactions play an important role in the prevention of several diseases. Conjugated linoleic acids (CLA) are ligands of gene regulators [e.g. peroxisome proliferator-activated receptors (PPAR)] and have anti-inflammatory properties. The aim of the study was to investigate the changes in gene expression in monocytes during the intervention with two trans fatty acids (trans-11 18:1 and trans-12 18:1) and endogenous CLA from trans-11 18:1 as precursor in humans. Monocytes were isolated at baseline and after a 6-wk intervention period. The female and male test groups received Σ6.0 g trans-11 and trans-12 18:1/day (1:1). The control group received control oil. The expression of candidate genes was detd. by quant. RT-PCR. Gender- and treatment-related gene expression was found. Due to trans fatty acid intake in both gender subgroups, the relative PPARγ expression was up-regulated. In the female test group, the expression of FAT, SCD, COX2 and BCL2 were induced, while in the male test group E-FABP, CYP, GLUT4 and PBE were induced. In the male test group compared to controls, a clear increase in gene expression of PPARγ and GLUT4 was shown. The results reveal a gender- and treatment-related gene expression. There is no clear indication as to what extent the supplemented trans fatty acids and the synthesized cis-9, trans-11 CLA were involved.

Missner U. Darmkrebsrisiko und Aufnahme von Kalzium, Vitamin D und Milchprodukten. Ernährungsumschau 2009, 6, 362-363
HUNCHAREK et al. recherchierten in Datenbanken im Zeitraum von Januar 1966 bis Februar 2007 unter Verwendung folgender Stichworte: Milchprodukte, [Calcium, diätetisch], diätetische Fette, Vitamin D und Kolon-/Rektaltumore. Nach Ausschluss verschiedener ungeeigneter Veröffentlichungen wurden 60 zur Analyse herangezogen (26 Fall-Kontroll-, 34 Kohortenstudien). Damit berücksichtigen die Autoren insgesamt 26 335 Krebsfälle.

Schäfer U, Jahreis G. Update on regulations of aluminium intake - biochemical and toxicological assessment. TRACE ELEMENTS AND ELECTROLYTES 26, 95-99, 2009
For aluminium (Al), the European Food Safety Authority (EFSA) has recently established a Tolerable Weekly Intake (TWI) of 1 mg Al/kg bw/week due to its neurotoxicity, embryotoxicity and adverse effects on the development of the nervous system. The TWI took the place of the Provisional Tolerable Weekly Intake (PTWI) of 0 - 7 mg Al/kg bw/week issued by FAO/WHO in 1989. The considerable reduction in the TWI for AI intake means a conflicting situation because a significant part of the European population exceeds the TWI value. Al absorption is a complex network of biochemical reactions which are influenced by several parameters and can vary up to 50-fold, depending on the chemical form of Al only. Al absorption is increased by low pH, high solubility of AI species, organic acids and their salts, a low Fe status and uremia, whereas it is decreased by phosphates or phosphate-rich compounds and silicates. The presence of citrate increases Al absorption also from AI compounds with low solubility. This outcome is very important regarding the fact that the human diet contains considerable amounts of citric acid which is reported to average 4 g (as citrate) in the daily diet. Elevated exposure of AI may produce accumulation of systemic Al and cause toxicity of the respiratory, central nervous, skeletal and hematopoietic systems. In this way, Al may induce lung fibrosis, the dialysis encephalopathy syndrome, a low bone turnover osteodystrophy and an erythropoietin-resistant microcytic anaemia. Due to the new regulation of the EFSA for reduced Al intake it is suggested to reconsider the allowance and use of Al-containing food additives being a main Al source in some foods. Furthermore, the contamination of Al in Ca compounds used as fortifiers in infant foods should be reduced to the lowest possible limit because infants are particularly susceptible to Al.

Schäfer U, Dawczynski C, Leiterer M., Schubert R, Jahreis G. Dietary value and toxicological potential of macroalgae products. TRACE ELEMENTS AND ELECTROLYTES 26, 100-100, 2009
Letter to the editor.

Schubert R, Kahle C, Kauf E, Hofmann J, Hobert I, Gruhn B, Häfer R, Vogelsang H, Jahreis G: Dietetic efficacy of mare’s milk for patients with chronic inflammatory bowel diseases - clinical study. ernährung/nutrition (accepted June 2009)
Background: Dietetic effects of mare’s milk have been reported for a long time and can be based on bactericidal and immunological components of mare’s milk.
Objective: Dietetic effects of oral intake of mare's milk in adolescent patients with chronic inflammatory bowel diseases were investigated.
Design: In a randomized, placebo-controlled, double-blind, cross-over intervention study, eight Crohn’s disease patients and nine ulcerative colitis patients received daily 250 mL mare’s milk or placebo drink.
Results: Consumption of mare's milk caused a lower abdominal and extraintestinal pain, reduced the occurrence of visible blood in the faeces and required lower medication to reduce the symptoms of bowel diseases compared to the placebo drink. The parameters of blood, urine and faeces as well as the Crohn's disease activity index and ulcerative colitis activity index were not influenced.
Conclusions: Mare’s milk consumption could improve the well-being in patients with Crohn’s disease and colitis ulcerosa, respectively.

Spielmeyer A, Wagner A, Jahreis G. Influence of thermal treatment of rapeseed on the canolol content. Food Chem 112 (2009) 944–948
4-Vinylsyringol, also referred to as canolol, is a highly active antioxidant and potent lipidperoxyl radical scavenger found in rapeseed.  The canolol content of rapeseed can be increased through the decarboxylation of sinapic acid via roasting treatments.  Different roasting conditions were tested and compared and an optimum for the canolol formation was found at 160 °C.  The canolol content of the rapeseed samples with optimal roasting increased by a factor of 120 in relation to the unroasted sample.  The rapeseed was ground, extd. and analyzed by normal-phase HPLC/UV.  The structure of canolol was confirmed by NMR and MS techniques.  Several rapeseed oils were purchased in German food stores and analyzed.  No differences in canolol content were obsd. in both cold-pressed and rape kernel oil samples tested.  Dehulled rapeseed samples demonstrated no significant difference in canolol content when compared to unpeeled rapeseed samples.

2008

Ditscheid B, Keller S, Jahreis G (2009) Faecal steroid excretion in humans is affected by calcium supplementation and shows gender-specific differences. Eur J Nutr 48, 22-30
Previous human studies on the effect of dietary calcium supplementation on faecal excretion of bile acids (BA) and faecal water concentrations of animal neutral sterols (NSt, cholesterol and its metabolites) lack detailed information about single BA and NSt.|We investigated whether single BA and NSt in faeces and especially in faecal water are affected by calcium supplementation and whether this affects genotoxicity of faecal water. In addition, we differentiated between men and women with regard to the concentrations of BA and NSt in faecal water.|Thirty-one healthy volunteers consumed a calcium supplemented bread (1.0 g/day) and a placebo bread, respectively, for 4 weeks in a double-blind, randomised cross-over trial. Faeces were collected quantitatively for 5 days in the last week of each period. NSt and BA were analysed by GC-MS.|Due to calcium supplementation faecal concentrations of lithocholic acid (LCA, 14%, P = 0.008), deoxycholic acid (DCA, 19%, P < 0.001) and 12keto-deoxycholic acid (12keto DCA, 29%, P = 0.049) significantly increased whereas BA concentrations in faecal water were only marginally affected. In contrast, concentrations of cholesterol (30%, P = 0.020) and its metabolites coprostanol (43%, P = 0.004), coprostanone (36%, P = 0.003), cholestanol (44%, P = 0.001) and cholestenone (32%, P = 0.038) in faecal water significantly decreased. Total NSt concentration in faecal water was found to be significantly higher in women compared to men (P = 0.018). The genotoxicity of faecal water was neither affected by calcium supplementation nor were there gender-specific differences.|Dietary calcium supplementation diversely affects BA and NSt in faeces and in faecal water but does not influence the genotoxicity of faecal water in healthy adults.

Helbig D, Böhm V, Wagner A, Schubert R, Jahreis G, Berry seed press residues and their valuable ingredients with special regard to black currant seed press residues. Food Chem 111: 1043–1049, 2008
Berry seeds are distinguished by longevity though clear scientific appraisals cannot be made. Besides a hard seed coat other protecting substances are presumed in the seeds. Commonly the seeds are utilized as a source of oils. After pressing, there is a residue left that is still rich in bioactive ingredients. This paper gives an overview of the health-beneficial ingredients remaining in the residue of various berry seeds (bilberry, cranberry, rose hip, strawberry, elder, and black currant) with special focus on black currant. The fatty acid distribution and the content of fat, tocopherols and tocotrienols, phytosterols, carotenoids, vitamin C, fibre, protein, amino acids, dry matter, ashes, minerals, total phenols (gallic acid equivalent) and antioxidant capacity (TEAC) were determined. The investigation of berry seed press residues revealed that the total phenols and tocopherols were quantitatively the most important features of this material but there were significant differences between batches and cultures.

Kuhnt Katrin, Jahreis Gerhard. Trans fatty acids in human nutrition. Zywienie Czlowieka i Metabolizm 2007, 34, 46-54.
This review comprises the impact of trans fatty acids (tFA) and conjugated linoleic acids (CLA) in the human nutrition. The knowledge of the impact of the relation between dietary tFA and the risk of cardiovascular diseases, diabetes mellitus type-2, and cancer increased in the last years. There is increasing evidence that the effects of tFA on human health differ among positional trans-isomers. CLA show various metabolic properties, mainly anti-cancerogenic, anti-inflammatory, and anti-atherogenic, with potent impact in humans.

Jaudszus A, Krokowski M, Möckel P, Darcan Y, Avagyan A, Matricardi P, Jahreis G, Hamelmann E. Cis-9,trans-11-conjugated linoleic acid inhibits allergic sensitization and airway inflammation via a PPARgamma-related mechanism in mice. J Nutr 2008;138:1336-1342
Milk consumption from early childhood on has been found to be inversely correlated with allergic sensitization and the onset of bronchial asthma. We tested whether cis-9,trans-11-conjugated linoleic acid (c9,t11-CLA), naturally occurring in milk fat, may prevent allergic sensitization and inhibit airway inflammation in a murine asthma model. BALB/c mice were fed a diet enriched in 1 wt% of c9,t11-CLA or a control diet 7 d prior to and for 32 d during sensitization [d 1 and 14, 100 mg/L ovalbumin (OVA) in adjuvant vs. PBS] and airway challenges (d 28-30, 1% OVA in PBS vs. PBS). Subgroups of mice were coadministered 20 micromol/L of the selective PPARgamma antagonist GW9662 during each OVA challenge. C9,t11-CLA feeding resulted in significantly reduced IgE production and allergen-induced in vivo airway hyperresponsiveness. Further, less mucous plugging of segmental bronchi and significantly reduced interleukin-5 and eosinophils were determined in bronchoalveolar lavage fluids of c9,t11-CLA-fed mice. C9,t11-CLA feeding prevented the downregulation of PPARgamma mRNA in the lung tissues observed after allergen sensitization and airway challenges in control mice. The inhibitory effects of c9,t11-CLA on airway inflammation were partially prevented by coadministration of GW9962. Further, c9,t11-CLA feeding resulted in a significantly lower concentration of the eicosanoid precursor, arachidonic acid, in tissue lipids. These findings demonstrate that dietary c9,t11-CLA can reduce allergic airway inflammation, most likely via a PPARgamma-related mechanism and by reducing eicosanoid precursors. They give new insights into the fatty acid-mediated mechanism of immunomodulation and may represent a step toward an attractive novel strategy in the dietary prevention and treatment of allergic asthma.

Steinert, Robert E.; Ditscheid, Bianka; Netzel, Michael; Jahreis, Gerhard. Absorption of black currant anthocyanins by monolayers of human intestinal epithelial Caco-2 cells mounted in Ussing type chambers. J Agric Food Chem 2008 Jun 10. [Epub ahead of print]
Anthocyanins (ACNs) have been reported to have multiple biological properties imparting benefits to human health. Their role in human nutrition, however, needs to be related to biokinetic data, such as bioavailability. The purpose of the present study was to focus on the potential absorption of black currant ( Ribes nigrum L.) ACNs. Caco-2 monolayers were used as an in vitro model of the absorptive intestinal epithelium. For absorption studies, Caco-2 cells grown on permeable filters were mounted into Ussing type chambers. The monolayer integrity was monitored by measuring the transepithelial electrical resistance (TEER). Luminal to serosal transport of ACNs was examined by comparing ACN disappearance from the luminal solution of Ussing chambers not containing any inserts (control chambers) with that of Ussing chambers containing inserts. ACNs (C total ACN approximately 180 microM) were not detected in any serosal solution. However, it was shown that ACNs disappeared from the luminal side, not due to ACN degradation processes but ratherat least in partdue to physiological actions of the cells. The luminal net disappearance of ACNs was calculated (max t 20 min approximately 11% for total ACNs) and labeled as "absorption efficiency". This apical transport might occur to a much larger extent than the further translocation across the basolateral membrane. Thus, cell metabolism and translocation across the basolateral membrane may be the key determinants of ACN absorption and bioavailability.

Kraft J, Kramer JKG, Schoene F, Chambers JR, Jahreis G: Extensive analysis of long-chain polyunsaturated fatty acids, CLA, trans-18:1 isomers, and plasmalogenic lipids in different retail beef type. J Agr Food Chem 2008 May 21 [Epub ahead of print]
The objective of this investigation was to provide a comprehensive analysis of the total lipid composition of present-day retail beef meat available at the consumer level and to evaluate the total lipid composition with special emphasis on the nutritional value. For this purpose, 40 beef cuts were obtained from four cattle farms based on either a natural grazing system (NGS) or an intensive production system (IPS). The total lipid composition was analyzed using complementary chemical and chromatographic procedures. The content of n-3 LC-PUFA, CLA, total trans-18:1, and branched-chain fatty acids was significantly higher in NGS beef than in IPS beef. The trans-18:1 and CLA profiles were affected by the different production systems, whereby they can be utilized empirically to differentiate between feeding regimen and production management. Fatty acid ratios that have health implications ( n-6/ n-3, LA/alphaLNA, and AA/EPA) were remarkably beneficial for NGS beef compared with IPS beef. In conclusion, from the human health perspective, beef raised on NGS is clearly superior with regard to a more favorable fatty acid profile in comparison to IPS beef.

Klein, A.; Friedrich, U.; Vogelsang, H.; Jahreis, G. Lactobacillus acidophilus 74-2 and Bifidobacterium animalis subsp lactis DGCC 420 modulate unspecific cellular immune response in healthy adults. European Journal of Clinical Nutrition  (2008), 62(5),  584-593
Objective: It was detd. whether a combination of Lactobacillus acidophilus (L. acidophilus) 74-2 and Bifidobacterium animalis subsp lactis DGCC 420 (B. lactis 420) affect the faecal microbiota as well as immunol. parameters and blood lipids in healthy adults.  Design: A placebo-controlled, double-blinded, randomized crossover trial was conducted.  Subjects: Twenty- six healthy volunteers (mean age 25 years) were recruited by advertising in academical buildings.  All of them completed the study.  Methods: After 3-wk run-in period, half of the volunteers consumed 300 g/day of yoghurt supplement contg. probiotic strains L. acidophilus 74-2 and B. lactis 420, and the other half received the placebo product for a period of 5 wk.  The two groups were crossed during the following 5-wk period.  Blood and faecal samples were collected at the end of each period. The faecal content of probiotic bacteria, faecal short-chain fatty acids (SCFA), serum lipids and plasma immune system biomarkers were evaluated.  Results: Faecal proportions of L. acidophilus and of B. lactis increased significantly from 0.02 to 0.19 and 0.4 to 1.4% (P<0.05), resp.  Percentages of granulocytes and monocytes showing phagocytic activity were significantly elevated from 92 to 95% during probiotic intervention, whereas their oxidative burst activity and specific immune parameters remained unaffected.  Fecal SCFA and serum cholesterol levels were not influenced by the probiotics. However, serum concns. of triacylglyceroles decreased significantly by 11.6% (P<0.05) in the probiotic supplementation period.  Conclusions: L. acidophilus and B. lactis were recovered in faeces in significantly elevated nos. after supplementation.  They are able to modulate unspecific cellular immune response indicated by the increased phagocytic activity.

Roessler A, Friedrich U, H. Vogelsang H, Bauer A, Kaatz M, Hipler U.C, Schmidt I, Jahreis G: The immune system in healthy adults and patients with atopic dermatitis seems to be affected differently by a probiotic intervention. Clin Exp Allergy 2008, 38: 93-102
Background. Probiotic bacteria are proposed to alleviate atopic dermatitis (AD) in infants. There are few indications about the effect of probiotics on AD in adults. Objective. The purpose of this study was to elucidate the influence of a probiotic drink containing a combination of the probiotics Lactobacillus paracasei Lpc-37, Lactobacillus acidophilus 74-2 and Bifidobacterium animalis subsp. lactis DGCC 420 (B. lactis 420) in healthy volunteers and in patients with AD on clinical and immunological parameters and their detection in feces. Methods A double-blind, placebo-controlled, randomized cross-over study was conducted in 15 healthy adults and 15 patients with AD. The probiotic product or placebo was given over 8 weeks. A 2-week washout period was interconnected before the intervention was crossed. At the end of each period, blood and stool samples were collected. In patients, the severity of AD was evaluated using the Scoring of Atopic Dermatitis (SCORAD). Results. L. paracasei and B. lactis were recovered in high numbers in feces after supplementation, whereas L. acidophilus marginally increased. In patients, the SCORAD tended to decrease by 15.5% (P=0.081). Major lymphocyte subsets were not affected by the probiotic intervention. However, CD57(+) increased significantly (P=0.034) in healthy subjects after probiotic intake and was not changed in patients, whereas CD4(+)CD54(+) decreased significantly (P=0.031) in patients with AD and remained uninfluenced in healthy subjects. The expression of CD4(+)CD25(+) T cells was similar in healthy subjects and AD patients. The phagocytic activity of monocytes and granulocytes was significantly increased in healthy subjects after probiotic intervention (P=0.014). Conclusion. L. paracasei Lpc-37 and B. lactis 420 are able to colonize the intestine transiently. This study reveals that the probiotics differently modulate peripheral immune parameters in healthy subjects and patients with AD.

Keller S, Gimmler F, Jahreis G.: Octacosanol administration to humans decreases neutral sterol and bile Acid concentration in feces. Lipids. 43(2):109-15, 2008
To investigate octacosanol (OC) metabolism in humans and its influence on cholesterol metabolism, two studies were conducted. In the first study ten healthy women received daily 30 mg OC for a period of 4 weeks. Blood and feces samples were collected at baseline and after the intervention. Serum concentrations of total cholesterol, LDL cholesterol, and HDL cholesterol were not altered following OC administration. Concentrations of excreted cholesterol end products decreased with the intervention (neutral sterols: 24.6 +/- 9.7 mg/g vs. 20.3 +/- 7.5 mg/g dry matter, P < 0.05; bile acids: 6.47 +/- 3.89 mg/g vs. 4.03 +/- 2.26 mg/g dry matter, P < 0.05). OC was not detected in serum samples, but the fecal OC concentration increased after the intervention period (11 +/- 7 mug/g vs. 817 +/- 179 mug/g dry matter, P < 0.05). In the second kinetic study on three participants, OC was identified in serums after oral application of 50 mg OC within 8 h. The decrease in the concentration of fecal cholesterol end products may underline a systemic effect of OC on cholesterol metabolism, even though the serum cholesterol levels were not influenced.

2007

Keller S, Helbig D, Härtl A, Jahreis G. Nanoscale and customary non-esterified sitosterols are equally enriched in different body compartments of the guinea pig. Mol Nutr Food Res 51(12):1503-1509, 2007
The impact of sitosterol formulation particle size on the intestinal sterol absorption and the sterol status in various tissues in Dunkin Hartley guinea pigs was investigated. Three groups of animals (six each) were fed a basal diet ("control") or a basal diet containing either customary sitosterol ("customary", particle size: 10 000-90 000 nm) or nanoscale sitosterol ("nanoscale", particle size: 200-300 nm). The average daily sitosterol intake was 21 +/- 7 mg (control), 154 +/- 8 mg (customary), and 127 +/- 18 mg (nanoscale) for 2 weeks. Sitosterol and cholesterol were analyzed in samples of plasma, blood cells, bile, liver, kidney, jejunal mucosa/serosa, cecum, colon and feces. Concentrations of sitosterol in all analyzed matrices increased significantly in the supplemented groups when compared to control group. No differences in the sitosterol concentrations in analyzed matrices occurred between nanoscale and customary group. The cholesterol concentrations in tissues remained unchanged. Fecal fatty acid and sterol distributions were modified during sitosterol intervention. Both particle sizes equally increased sitosterol levels in cholesterol-metabolizing compartments in the guinea pig. No differences in body compartment accumulation and intestinal absorption of the different sitosterol particle sizes were observed.

Dawczynski C, Schäfer U, Leiterer M, Jahreis G. Nutritional and Toxicological Importance of Macro, Trace, and Ultra-Trace Elements in Algae Food Products. J Agric Food Chem. 55(25):10470-10475, 2007
The content of 5 macro elements (Na, K, Ca, Mg, and P), 6 trace elements (Fe, Mn, Zn, Cu, Se, and I), and 4 ultra-trace elements (As, Pb, Cd, and Hg) in 34 edible dried seaweed products of brown algae (Laminaria sp., Undaria pinnatifida, and Hizikia fusiforme) and red algae ( Porphyra sp.) originated from China, Japan, and Korea and bought by retail in Germany was determined. The content of these elements was analyzed by spectrometric methods (ICP-AES, ICP-MS, HGAAS, and CVAAS). Assuming a daily intake with 5 g FM of algae, the contribution of the essential elements to the diet is low, with the exception of I. Brown algae contained as much as 1316 +/- 1669 mg of I/kg FM. More than 4000 mg of I/kg FM were found in several Laminaria sp. Moreover, some brown algae, such as Hizikia fusiforme, had high contents of total As (87.7 +/- 8.2 mg/kg FM).

Jürgens K, Kraft J, Jahreis G. Nutrition of patients with adrenoleucodystrophy (ALD) and adrenomyeloneuropathy (AMN). Ernährungs-Umschau 54:188-194, 2007
Adrenoleucodystrophy (ALD) is a rare x-linked, recessive disorder, characterized by an abnormal accumulation of saturated very long-chain fatty acids (VLCFA) in body tissues and plasma, associated with a progressive demyelinization of the central nervous system accompanied by adrenal insufficiency (M. Addison). The symptoms range from slowly progressing gait disorders to severe-often fast progressing and fatal-cerebral deficits such as blindness, deafness and dementia. To date, effective therapies are not available. VLCFA plasma levels may be normalized by a diet low in fat and VLCFA in combinatiom with intake of Lorenzo's oil (R), a mixture of monounsaturated oleic acid (C18:1) and erucic acid (C22:1 n-9) which competitively inhibit the endogenous synthesis of VLCFA. Major aim of the present study were reliable dietary recommendations for German ALD patients in view of the fact that existing advices are often unclear and to some extent incorrect. VLCFA contents of 68 common German food items were analyzed. ALD patients should generally prefer a low-fat diet and avoid food containing high amounts of VLCFA such as peanuts and peanut oil. Intake of high-fat dairy products, bananas, whole-grain based bread and other products containing moderate amounts of VLCFA should be reduced. VLCFA intake may be reduced (by about 65%) by an appropriate choice of food items. A mixture of special plant oils was developed which could be a promising and less expensive alternative to the high-priced Lorenzo's oil.

Kuhnt K, Kraft J, Vogelsang H, Eder K, Kratzsch J, Jahreis G: Dietary supplementation with trans-11- and trans-12-18:1 increases cis-9, trans-11-conjugated linoleic acid in human immune cells, but without effects on biomarkers of immune function and inflammation. British Journal of Nutrition (2007), 97, 1196–1205
Trans-fatty acid intake is associated with an increased risk of CHD and diabetes. The effects of single trans-fatty acid isomers are largely unexplored. The present study examined the effects of a 6-week supplementation with two trans-18:1 isomers (trans-11 and trans-12) in human subjects on immune cells, several inflammatory and immunological biomarkers (for example, IL, TNFα, C-reactive protein, adiponectin, intercellular adhesion molecule-1, prostacyclin, phagocytic process). Following a 2-week adaptation period without supplements, the test group (n 12) received vaccenic acid (trans-11-18:1) and trans-12-18:1 in equal amounts (6.0 g/d) for 6 weeks. The control group (n 12) consumed an oil without trans fatty acids and conjugated linoleic acids (CLA). Samples were collected at the end of both periods. Trans-11- and trans-12-18:1 were significantly increased in cellular lipids. The endogenous synthesis of cis-9, trans-11-CLA from trans-11-18:1 was demonstrated via increased CLA in cellular lipids of the test group. Generally, trans-isomer supplementation did not affect either inflammatory biomarkers (for example, IL-6, IL-8, TNFα) or immune function (for example, phagocytosis) during the present study. The dietary supplementation of trans-11- and trans-12-18:1 (6 g/d) and their accumulation in leucocytes had no effects on biomarkers of inflammation and immune function. How ever, because of the limited data on the safety of trans-fatty acid intake and effects of individual trans isomers on human health (for example, trans-9-18:1, trans-10-18:1) at present, it is prudent to reduce trans-fat intake in general.

Dawczynski C, Schubert R, Jahreis G: Amino acids, fatty acids, and dietary fibre in edible seaweed products. Food Chemistry 103 (2007): 891–899
The nutritional compositions of 34 edible seaweed products of the Laminaria sp., Undaria pinnatifida, Hizikia fusiforme and Porphyra sp. varieties were analyzed. This study determined amino acid and fatty acid (FA) distributions and contents of protein, fat, and total fibre of these seaweed varieties. In general, the marine macroalgae varieties tested demonstrated low lipid contents with 2.3 ± 1.6 g/100 g semi-dry sample weight (s.w.) and proved to be a rich source of dietary fibre (46.2 ± 8.0 g/100 g s.w). The pure protein content of seaweed products varied widely (26.6 ± 6.3 g/100 g s.w. in red algae varieties and 12.9 ± 6.2 g/100 g s.w. in brown algae varieties). All essential amino acids were detected in the seaweed species tested and red algae species featured uniquely high concentrations of taurine when compared to brown algae varieties. Interestingly, the FA distribution of seaweed products showed high levels of n-3 FA and demonstrated a nutritionally ideal n-6/n-3 FA ratio. The predominante FA in various seaweed products was eicosapentaenoic acid (C20:5, n-3) which was at concentrations as high as 50% of total FA content.

Seidel C, Boehm V, Vogelsang H, Wagner A, Persin C, Glei M,. Pool-Zobel BL and Jahreis G: Influence of prebiotics and antioxidants in bread on the immune system, antioxidative status and antioxidative capacity in male smokers and non- smokers. Br J Nutr  97 (2007): 349-356
Interest in functional foods is increasing. The aim of the present study was to investigate breads supplemented with functional components. One was bread supplemented with inulin, linseed and soya fibre (prebiotic bread). The other was a prebiotic antioxidant bread (pre-aox-bread), which additionally contained green tea powder, herbs and tomato paste. The effects of these two breads on immunological and antioxidative parameters were compared with control bread (placebo). Twenty smokers and eighteen non-smokers were enrolled in the randomised parallel study, which consisted of a control period and an intervention period, each lasting for 5 weeks. Daily intake of bread and nutrients did not differ between the intervention and the control period. Most of the twenty-three investigated immunological parameters measured in peripheral blood were unaffected. However, the percentage of CD19 increased after intervention with prebiotic bread, whereas intercellular adhesion molecule-1 (ICAM-1) and CD3+NK+ (P<0,05) decreased in both intervention arms. The ferric reducing ability of plasma (FRAP) was increased after consumption of the pre-aox-bread for non-smokers (1256 v. 1147 mmol/l; P=0·019) and remained unchanged for smokers consuming the preaox-bread. All analysed carotenoids (P<0·001) in plasma were increased after the consumption of pre-aox-bread. The concentrations of uric acid and a- tocopherol rose after intervention with both breads. ICAM-1 as a marker of stress decreased after consuming the prebiotic bread.
In conclusion, increased plasma concentrations of carotenoids and the responses observed with the FRAP assay after intervention with the preaox-bread indicate a unique response in terms of antioxidative potentials for this type of functional food.