Time filter

Source Type

Andersen G.,German Research Center for Food Chemistry | Burkon A.,German Research Center for Food Chemistry | Sulzmaier F.J.,German Research Center for Food Chemistry | Walker J.M.,University of Vienna | And 5 more authors.
Molecular Nutrition and Food Research | Year: 2011

Scope: trans-Resveratrol has been shown to improve insulin sensitivity and to enhance cellular glucose uptake. Evidence from recent studies indicates that these effects depend on SIRT1-pathways. Methods and results: Since ingestion of resveratrol leads to the presence of resveratrol and resveratrol metabolites in the body, we aimed at investigating (i) whether a daily dose of 300mg resveratrol/kg body weight in healthy male Wistar rats for a period of 8wk affects the selected parameters of glucose and lipid metabolism and (ii) whether the resulting plasma concentrations of resveratrol metabolites were effective in modulating SIRT1 expression. The dietary dose was based on the results from preceding toxicity studies. The results from the feeding experiment revealed plasma concentrations of resveratrol and its metabolites below 1μmol/L and showed that fasting glucose and insulin levels were decreased by 35 and 41%, respectively, in the resveratrol group compared with controls. Insulin sensitivity was enhanced by 70%, whereas liver SIRT1 protein expression was not affected. Treatment of HepG2 cells with 10μM resveratrol (1.49-fold) or its diglucuronides (1.21-fold) increased SIRT1 expression. Conclusion: These results suggest that the improved insulin sensitivity after dietary administration of 300mg resveratrol/kg body weight does not involve increased protein expression of SIRT1. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

If research in male fruit flies holds up, it might help you live longer. A new research report published in the February 2016 issue of The FASEB Journal, shows that administering an oral dose of prunetin to male fruit flies extends lifespan, increases fitness levels, and improves their glucose balance. This effect was not found in females. Prunetin is a plant-derived compound that belongs to the isoflavone group. "Our study provides novel insights into plant bioactive research and suggests a potential to combat aging comparatively simple by the intake of a plant bioactive," said Anika E. Wagner, Ph.D., a researcher involved in the work from the Institute of Human Nutrition and Food Science at Christian-Albrechts-University Kiel, in Kiel, Germany. "Further studies in mammalian species/humans are needed to validate initial data which were generated in the model organism Drosophila melanogaster." To make their discovery, scientists separated fruit flies according to sex prior to the start of the experimental treatment to compare prunetin-mediated effects on both males and females. The flies were then chronically administered either a prunetin-containing diet or a prunetin-free control diet. The flies were monitored every other day, and dead flies were counted. The researchers found that prunetin-fed male flies lived longer than those receiving the control diet. To evaluate their health state / fitness, the flies were coerced to climb up in a transparent tube and the distance which they could overcome in a defined time period was calculated. "This research shows that the connection between diet and health is important for all living animals, no matter how complex or how simple they are," said Thoru Pederson, Ph.D., Editor-in-Chief of The FASEB Journal. "There is a lot of work that must be done before we would know if this compound will be useful to humans, but it certainly doesn't hurt to add lima beans to more men's diets." Explore further: Fruit flies with better sex lives live longer More information: S. Piegholdt et al. The phytoestrogen prunetin affects body composition and improves fitness and lifespan in male Drosophila melanogaster, The FASEB Journal (2015). DOI: 10.1096/fj.15-282061

Frenzel M.,Institute of Human Nutrition and Food Science | Steffen-Heins A.,Institute of Human Nutrition and Food Science
Food chemistry | Year: 2015

Liposomes are suitable for encapsulating lipophilic bioactive compounds, enhancing compound solubility, stability and bioavailability. To enhance physical stability of liposomes in food-like matrices they were coated with positively charged whey protein isolate (WPI). WPI concentration, for a successful coating, was optimised by dynamic light scattering (DLS) and zeta potential measurements. Membrane properties of coated and uncoated vesicles were investigated by electron paramagnetic resonance (EPR) with site-directed and non-site-directed spin probes. Coexistence of two or three simulated spin probe populations indicated a less fluid membrane and higher concentration of water molecules in the phosphate/glycerol moiety with WPI coating. This relies on the insertion of WPI into the membrane, which is favoured by the molten globule state under investigated acidic conditions. Physical stability of liposomes benefits from WPI coating, as indicated by prolonged shelf-life, cancellation of osmotic effects in the presence of salts or sugars and a lower sensitivity towards low pH values during in vitro gastric digestion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fischer A.,Institute of Human Nutrition and Food Science | Onur S.,Institute of Human Nutrition and Food Science | Niklowitz P.,Childrens Hospital of Datteln | Menke T.,Childrens Hospital of Datteln | Doring F.,Institute of Human Nutrition and Food Science
BioFactors | Year: 2016

In the present study the relationship between the CoQ10 redox state (% oxidized form of CoQ10) and the serum level of c-reactive protein (CRP) was investigated in a large Caucasian study population (n=1319). In order to evaluate independently the influence of the variables that predict the outcome of CRP, an analysis of covariance (ANCOVA) was performed with CRP as the dependent variable. Gender was taken as an independent factor and CoQ10 redox and BMI as independent covariates. Results were substantiated with findings from a human intervention study (n=53), receiving 150 mg/day ubiquinol for 14 days. Spearman's correlation revealed a significant (P<0.001) association between the CoQ10 redox state and CRP concentrations in the whole study population. Thus, higher CRP concentrations were found in subjects having more oxidized CoQ10. Similar results were evident for further inflammatory markers (interleukin-6, number of leucocytes). The ANCOVA revealed a significant (P<0.001) prediction of CRP concentrations by CoQ10 redox state, after controlling for the effect of BMI and separately for gender. In the intervention study it was further found that the oral intake of ubiquinol increased its proportion significantly (P<0.001), with the highest increase in those persons having a low basal serum ubiquinol content (<92.3%). Here it was discovered that the ubiquinol status significantly correlated to the concentration of the inflammation marker monocyte chemotactic protein 1. It is concluded that CoQ10 redox state predicts the concentration of CRP. Persons at risk with lower ubiquinol status, higher BMI, and low grade inflammation may benefit from ubiquinol supplementation. © 2016 International Union of Biochemistry and Molecular Biology.

Huebbe P.,Institute of Human Nutrition and Food Science | Lange J.,Institute of Human Nutrition and Food Science | Lietz G.,Rural University | Rimbach G.,Institute of Human Nutrition and Food Science
BioFactors | Year: 2016

The human apolipoprotein E (APOE) genotype has been suggested to interact with nutrient metabolism particularly with lipid soluble vitamins. Plasma carotenoid levels are determined by numerous dietary and genetic factors with high inter-individual variation; however, the APOE genotype has not been systematically examined so far. Our aim was to investigate the effect of the APOE genotype on dietary carotenoid metabolism with special regard to transcriptional regulation of carotenoid absorption, cleavage and adipocyte fat storage. We supplemented targeted replacement mice expressing human APOE3 and APOE4 isoforms with dietary beta-carotene (BC) and lutein (LUT) for 8 weeks. Plasma BC and adipose tissue BC and LUT levels were in trend lower in APOE4 than APOE3 mice, while hepatic expression of the beta-carotene oxygenases BCO1 and BCO2 was significantly higher. In contrast to the liver, mRNA levels of proteins involved in carotenoid absorption and cleavage in the small intestinal mucosa as well as of adipogenic markers in the adipose tissue were not different between APOE3 and APOE4 mice. Our data suggest that the hepatic carotenoid cleavage activity is higher in APOE4 mice partially reducing the circulation and extra-hepatic accumulation of intact carotenoids as compared to APOE3. Therefore we suggest considering the APOE genotype as modulator of carotenoid status in the future. © 2016 International Union of Biochemistry and Molecular Biology.

Discover hidden collaborations