Project description:Dietary n-3 polyunsaturated fatty acids can reduce inflammation via a range of mechanisms. This study tested the effect of dietary eicosapentaenoic acid (EPA) on intestinal inflammation using interleukin-10 gene-deficient (Il10-/-) mice. Methods: At 35 days of age, 12 weaned Il10-/- and 12 C57 mice were randomly assigned to one of two modified AIN-76A diets, supplemented with 3.7% purified ethyl esters of either EPA (n-3) or oleic acid (OA, control). To identify genes relevant to colon inflammation, transcription profiling (microarrays and qRT-PCR) and bioinformatic analyses were used. Results: In this study, dietary EPA reversed the decrease in colon fatty acid β-oxidation gene expression observed in OA-fed Il10-/- compared to C57 mice. Il10-/- mice fed the OA diet showed decreased expression of antioxidant enzyme genes, as well as those involved in detoxification of xenobiotics, compared to C57 mice on the same diet. In contrast, dietary EPA increased the expression of these genes in Il10-/- mice. Conclusions: These data indicate that dietary EPA induced endogenous lipid oxidation which might have a potential anti-inflammatory effect on colon tissue. This is supported by the activation of the Ppara gene that regulates the expression of pro-inflammatory and immunomodulatory genes and proteins. Experiment Overall Design: The diet abbreviations EPA, OA, AA and CO used in the sample records Experiment Overall Design: refer to the following : Experiment Overall Design: CO : AIN-76A (control) Experiment Overall Design: OA : AIN-76A (fat-free) + 1% corn oil + 3.7% oleic acid Experiment Overall Design: EPA : AIN-76A (fat-free) + 1% corn oil + 3.7% eicosapentaenoic acid Experiment Overall Design: AA : AIN-76A (fat-free) + 1% corn oil + 3.7% arachidonic acid Experiment Overall Design: Corn oil was supplemented with purified linoleic and alpha-linolenic acid to meet the nutritional requirements of mice for these essential fatty acids. Diets fed for 6 weeks.
Project description:Dietary n-3 polyunsaturated fatty acids can reduce inflammation via a range of mechanisms. This study tested the effect of dietary eicosapentaenoic acid (EPA) on intestinal inflammation using interleukin-10 gene-deficient (Il10-/-) mice. Methods: At 35 days of age, 12 weaned Il10-/- and 12 C57 mice were randomly assigned to one of two modified AIN-76A diets, supplemented with 3.7% purified ethyl esters of either EPA (n-3) or oleic acid (OA, control). To identify genes relevant to colon inflammation, transcription profiling (microarrays and qRT-PCR) and bioinformatic analyses were used. Results: In this study, dietary EPA reversed the decrease in colon fatty acid β-oxidation gene expression observed in OA-fed Il10-/- compared to C57 mice. Il10-/- mice fed the OA diet showed decreased expression of antioxidant enzyme genes, as well as those involved in detoxification of xenobiotics, compared to C57 mice on the same diet. In contrast, dietary EPA increased the expression of these genes in Il10-/- mice. Conclusions: These data indicate that dietary EPA induced endogenous lipid oxidation which might have a potential anti-inflammatory effect on colon tissue. This is supported by the activation of the Ppara gene that regulates the expression of pro-inflammatory and immunomodulatory genes and proteins.
Project description:The Ability of Dietary Polyunsaturated Fatty Acids to Protect Against Liver Inflammation and Non-Alcoholic Steatohepatitis (NASH) is Dependent on Gut Microbes
Project description:The aim of the study is to establish the existence of a relationship between the dietary intake of polyunsaturated fatty acids (PUFA) and the risk of colorectal cancer in humans, using 2 reliable and complementary biomarkers: the fatty acid-composition of lipids of the abdominal subcutaneous adipose tissue and the fatty acid composition of erythrocyte phospholipids.
Project description:The current study was designed to determine if dietary fatty acid concentration and composition affects the development and progression of nonalcoholic fatty liver disease. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated), or corn oil (polyunsaturated). Overfeeding 5% corn oil produced little steatosis relative to feeding 5% olive oil. This was associated with lower fatty acid synthesis and reduced SREBP-c signaling in the 5% corn oil group. Overfeeding 70% fat diets increased steatosis and lead to increased liver necrosis in the 70% corn oil but not olive oil group. Increased injury after feeding polyunsaturated fat diets was linked to peroxidizability of hepatic free fatty acids and triglycerides and appearance of peroxidaized lipid products HETES and HODES previously linked to clinical nonalcoholic steatohepatitis. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated) or corn oil (polyunsaturated).
Project description:Intestinal lipid absorption, the entry point for fats into the body, requires the coordinated actions of bile acids and lipases. Here, we uncover distinct yet cooperative roles of bile acids in driving the differential uptake of dietary fatty acids. We first decreased the bile acid pool size by disrupting the rate-limiting enzyme in bile acid synthesis, Cyp7a1, using liver-directed gene editing in mice. Compared with lipase inhibition, reduced bile acids prevented diet-induced obesity, increased anorectic hormones, suppressed excessive eating, and improved systemic lipid metabolism. Remarkably, decreasing bile acids selectively reduced the absorption of saturated fatty acids but preserved polyunsaturated fatty acids. By targeting additional bile acid enzymes, we identified specific functions of individual bile acid species. Mechanistically, we show that cholic acid preferentially solubilizes polyunsaturated fatty acids into mixed micelles for intestinal uptake. Our studies demonstrate that bile acids can selectively control fatty acid uptake, revealing insights for future interventions in metabolic diseases.
Project description:Analysis of variation in subcutaneous adipose tissue gene expression in response to dietary intake of n-3 polyunsaturated fatty acids, as assessed in a cohot of individuals with metabolic syndrome. Outcomes from this study provide insight on molecular details of dietary effects on gene expression and metabolic health. Subcutaneous adipose tissue samples were taken from a cohort of seventeen individuals with metabolic syndrome. Habitual intake of n-3 polyunsaturated fatty acids was assessed with 3-day weighed food journals.
Project description:Omega-3 and omega-6 polyunsaturated fatty acids (PUFA) have important signalling roles in the body. The goal of this study was to investigate the impact of linoleic acid (LA, omega-6) and alpha-linolenic (ALA, omega-3) on global skeletal muscle gene expression. We were also interested to study the impact of these fatty acids on myokine expression. To differentiate the roles of essential dietary PUFA on skeletal muscle function, we fed male rats a control diet (AIN-93G) or diets containing 10% safflower oil or flaxseed oil. Skeletal muscle gene expression was investigated by microrray.
Project description:The present study aimed to determine the impact of dietary docosahexaenoic acid (DHA) on the metabolism of Atlantic salmon (Salmo salar). The effects of diets containing increasing levels of DHA (1 g kg-1, 5 g kg-1, 10 g kg-1, 15 g kg-1 and 20 g kg-1) on the liver transcriptome of post-smolt salmon was determined using regression analysis to elucidate patterns of gene expression and responses of specific metabolic pathways. Total RNA was isolated from liver of individual fish and analyzed using a custom 44K Atlantic salmon oligo-microarray. The expression of up to 911 unique annotated genes was significantly affected by dietary DHA inclusion relative to a low DHA reference diet. Using regression analysis, 797 unique genes were found with a significant linear correlation between expression level and dietary DHA. Gene-Set Enrichment Analysis (GSEA) identified a range of pathways that were significantly affected by dietary DHA content. Pathways that showed a significant response to dietary DHA level included those for long-chain polyunsaturated fatty acid biosynthesis, fatty acid elongation, steroid biosynthesis, glycan biosynthesis, protein export and protein processing in the endoplasmic reticulum. These findings suggest that in addition to clear roles in influencing lipid metabolic pathways, DHA also has key functional roles in other biosynthetic pathways distinct from lipid metabolism.