Project description:Prolonged intervention studies investigating molecular metabolism are necessary for a deeper understanding of dietary effects on health. Here we provide mechanistic information about metabolic adaptation to fat-rich diets. Healthy men ingested saturated (SFA) or poly unsaturated (PUFA) fat-rich diets for six weeks during weight maintenance. Hyperinsulinemic clamps combined with leg balance technique revealed unchanged peripheral insulin sensitivity, independent of fatty acid type. Both diets increased fat oxidation potential in muscle. Hepatic insulin clearance increased, while glucose production, de novo lipogenesis and plasma triacylglycerol decreased. High fat intake changed the plasma proteome in immune-supporting direction and the gut microbiome displayed changes at taxonomical and functional level with PUFA. In mice, eucaloric feeding of human PUFA and SFA diets lowered hepatic triacylglycerol content compared to low-fat fed control mice, and induced adaptations in the liver supportive of decreased gluconeogenesis and lipogenesis. Intake of fat-rich diets thus induces extensive metabolic adaptations enabling disposition of dietary fat without metabolic complications.
Project description:Acute effects of different dietary fatty acids on the gene expression profiles of peripheral blood mononuclear cells in healthy young men. A randomized cross-over study. Gene expression profiles of peripheral blood mononuclear cells (PBMCs) have been used to reflect pathological and physiological states of humans. We theorized that these cells could also be used to show fatty acid specific gene expression profiles. Since most individuals are in a postprandial state for the main part of the day, knowledge about acute effects of diet is highly valuable. In a cross over study, 21 healthy male volunteers were given shakes containing mainly polyunsaturated or saturated fatty acids. Before and 6 hours after intake of the shakes blood was taken and PBMCs were isolated to use for whole genome gene expression profiling, using Affymetrix NuGO_Hs1a52018 arrays. PUFA intake showed an decrease in LXR signaling and an increase in cellular stress response, while SFA intake showed an increase in LXR signaling.We conclude that PBMCs can reveal a fatty acid specific gene expression profile and in this study show an adverse effect on cellular stress responses of immune cells upon high PUFA intake. We hypothesize that these cells can therefore be used as biomarkers to reflect the capacity of cells to response to cellular stressors, such as fatty acids. Keywords: Acute fatty acid shake cross-over intervention study
Project description:BACKGROUND. Dietary intake of saturated fat is a likely contributor to nonalcoholic fatty liver disease (NAFLD) and insulin resistance, but the mechanisms that initiate these abnormalities in humans remain unclear. We examined the effects of a single oral saturated fat load on insulin sensitivity, hepatic glucose metabolism, and lipid metabolism in humans. Similarly, initiating mechanisms were examined after an equivalent challenge in mice. METHODS. Fourteen lean, healthy individuals randomly received either palm oil (PO) or vehicle (VCL). Hepatic metabolism was analyzed using in vivo 13C/31P/1H and ex vivo 2H magnetic resonance spectroscopy before and during hyperinsulinemic-euglycemic clamps with isotope dilution. Mice underwent identical clamp procedures and hepatic transcriptome analyses. RESULTS. PO administration decreased whole-body, hepatic, and adipose tissue insulin sensitivity by 25%, 15%, and 34%, respectively. Hepatic triglyceride and ATP content rose by 35% and 16%, respectively. Hepatic gluconeogenesis increased by 70%, and net glycogenolysis declined by 20%. Mouse transcriptomics revealed that PO differentially regulates predicted upstream regulators and pathways, including LPS, members of the TLR and PPAR families, NF-κB, and TNF-related weak inducer of apoptosis (TWEAK). CONCLUSION. Saturated fat ingestion rapidly increases hepatic lipid storage, energy metabolism, and insulin resistance. This is accompanied by regulation of hepatic gene expression and signaling that may contribute to development of NAFLD.
Project description:19 men were split into two groups. 10 were provided with a diet of twice the recommended daily intake of protein and 9 were provided meals with the recommended dietary intake of protein. Faecal samples were collected after 10 weeks on the diet. This project looked at determining any qualitative differences present in the self-proteins from each group.
Project description:Fermented dairy milks have been associated with many health benefits including the regulation of metabolic dysfunction. Different circulating clinical biomarkers have been used to explore the effect of fermented milks on metabolic health but the development of whole blood transcriptomics has recently been proposed as a source of novel biomarkers for this health outcome. In a randomised, cross-over study, we evaluate the changes in the whole blood transcriptome after the intake of a probiotic yoghurt compared to a milk acidified with gluconic acid in seven healthy young men. The effects of the dairy foods on whole blood gene expression were assessed at three time points during a 6 h postprandial test (800g single dose) and in the fasting state after a daily intake of the products over two-weeks (400g/d). RNA was extracted from Paxgene ® whole blood samples and sequenced on the Illumina HiSeq platform.
Project description:The purpose of this study was to conduct a randomized-controlled trial to evaluate the effect of a high-protein (HP) diet weight loss (WL) on changes in body composition, insulin sensitivity and skeletal muscle gene expression profile in postmenopausal women who were obese and randomized to one of three dietary intervention groups: 1) a weight maitenance group, 2) a weight loss group (normal protein intake, 0.8 g protein/kg body weight per day) and 3) a weight loss group (high protein intake, 1.2 g protein/kg body weight per day) and studies before and after they lost 10% of their body weight (WL groups) or a time-matched weight maintenacne period.
Project description:Skeletal muscle unloading due to joint immobilization induces skeletal muscle atrophy. However, the skeletal muscle proteome response to limb immobilization has not been investigated using SWATH methods. This study quantitatively characterized the muscle proteome at baseline, and after 3 and 14 d of unilateral lower limb (knee-brace) immobilization in 18 healthy young men (25.4 ±5.5 y, 81.2 ±11.6 kg). All muscle biopsies were obtained from the vastus lateralis muscle. Unilateral lower limb immobilization was preceded by four-weeks of exercise training to standardise acute training history, and 7 days of dietary provision to standardise energy/macronutrient intake. Dietary intake was also standardised/provided throughout the 14 d immobilization period.
Project description:Beneficial effects of long-chain omega-3 polyunsaturated fatty acids (n-3 FAs) are generally well-known from epidemiological studies, but the various mechanisms of action are not completely clarified. Regulation of gene expression is one known mechanism of action, but only very limited data of regulated pathways in humans after n-3 FA supplementation are available. Up to now, no studies compared gene expression changes after n-3 FA supplementation between normolipidemic and dyslipidemic subjects. Therefore, the aim of this study was to investigate the effects of n-3 FA administration on whole genome expression profiles in the blood of normo- and dyslipidemic subjects. We conducted an intervention study with normo- and dyslipidemic men aged between 29 and 51 years, which were subdivided into four groups with a balanced age distribution and randomized to either six fish oil capsules per day providing 1.5 g docosahexaenoic acid and 1.0 g eicosapentaenoic acid or corn oil capsules rich in linoleic acid per day for a period of 12 weeks. Venous blood samples were collected at baseline as well as after 4 hours, 1 week and 12 weeks of supplementation. For each investigation time point, the samples of each group were pooled together to minimize inter-individual variability. All subjects have successfully completed the study, but for the microarray experiments, nine subject samples were excluded. Therefore, the microarray experiments are based on the following group characteristics: normolipidemic fish oil group (FO-N): pool of nine RNAs from normolipidemic subjects supplemented with fish oil; normolipidemic corn oil group (CO-N): pool of six RNAs from normolipidemic subjects supplemented with corn oil; dyslipidemic corn oil group (CO-D): pool of eight RNAs from dyslipidemic subjects supplemented with corn oil; dyslipidemic fish oil group (FO-D): pool of nine RNAs from dyslipidemic subjects supplemented with fish oil. The twenty normolipidemic and the twenty dyslipidemic subjects were subdivided into two groups. Thus, a total of four groups with ten men per group passed through the study. To realize a comparable mean age between groups, the formation of groups was performed by stratified allocation according to subject's age. The four study groups were randomly assigned to different study products by an uninvolved collaborator. Subjects ingested either six FO or six corn oil (CO) capsules per day for a period of twelve weeks. The daily n-3 PUFA intake via FO capsules was 2.7 g (1.14 g DHA and 1.56 g EPA). The predominant FA of the CO capsules was the omega-6 (n-6) PUFA linoleic acid (LA, 18:2n-6). Thus, the daily LA intake via CO capsules was 3.05 g LA. The subjects were instructed to ingest the capsules together with food, three in the morning and three in the evening, and to maintain their usual exercise and dietary habits throughout the intervention time. As an exception, at the first intervention day, all six capsules were ingested at the same time in the morning after a standardised breakfast. During each visit, fasting blood samples were collected by venepuncture. Additionally, participants completed a questionnaire to obtain information about changes in medication, dietary (e.g., changes in weekly fish intake, preferred fish dishes or species, respectively) and lifestyle habits (e.g., physical activity), as well as the tolerability of the capsules. This record summarizes the results of 16 microarrays. The samples originate from whole blood of normo- and dyslipidemic subjects supplemented with either fish oil or corn oil for 4 h, 1 week and 12 weeks. Microarrays were hybridized in a loop design with one common reference using a dye-swap approach.
Project description:This data submission reports the effects of 12 weeks supplementaion of 10%w/v sucrose supplied in drinking water on the inguinal white adipose tissue mRNA profiles of male and female mice relative to control groups (littermates that received plain water instead). RNAseq was performed by Novogene and investigators performed all analyses downstream of readcount acquisition. Manuscript abstract: Almost all effective treatments for non-alcoholic fatty liver disease (NAFLD) involve reduction of adiposity, which suggests the metabolic axis between liver and adipose tissue is essential to NAFLD development. Since excessive dietary sugar intake may be an initiating factor for NAFLD, we have characterized the metabolic effects of liquid sucrose intake at concentrations relevant to typical human consumption in mice. We report that sucrose intake induces sexually dimorphic effects in liver, adipose tissue, and the microbiome; differences concordant with steatosis severity. We show that when steatosis is decoupled from impairments in insulin responsiveness, sex is a moderating factor that influences sucrose-driven lipid storage and the contribution of de novo fatty acid synthesis to the overall hepatic triglyceride pool. Our findings provide physiologic insight into how sex influences the regulation of adipose-liver crosstalk and highlight the importance of extrahepatic metabolism in the pathogenesis of diet-induced steatosis and NAFLD.