Project description:Increasing the consumption of dietary fibre has been proposed to alleviate the progression of non-communicable diseases such as obesity, type 2 diabetes and cardiovascular disease, yet the effect of dietary fibre on host physiology remains unclear. In this study, we performed a multiple diet feeding study in C57BL/6J mice to compare high fat and high fat modified with dietary fibre diets on host physiology and gut homeostasis by combining proteomic, metagenomic, metabolomic and glycomic techniques with correlation network analysis. We observed significant changes in physiology, liver proteome, gut microbiota and SCFA production in response to high fat diet. Dietary fibre modification did not reverse these changes but was associated with specific changes in the gut microbiota, liver proteome, SCFA production and colonic mucin glycosylation. Furthermore, correlation network analysis identified gut bacterial-glycan associations.
Project description:Background: The long-term high-fat, high-sugar diet exacerbates type 2 diabetes mellitus (T2DM)-related cognitive impairments. The negative impact of poor dietary patterns on brain development and neurological function may be related to gut microbiota disturbance. The role of phlorizin in mitigating glucose and lipid metabolism disorders is well documented. However, the protective effect of phlorizin on diabetes-related cognitive dysfunction is unclear. Therefore, the present study aimed to investigate the effect of dietary supplementation of phlorizin on high-fat and high-fructose diet (HFFD)-induced cognitive dysfunction and evaluate the crucial role of the microbiota-gut-brain axis. Results: Dietary supplementation of phlorizin for 14 weeks effectively prevented glucolipid metabolism disorder, spatial learning impairment, and memory impairment in HFFD mice. In addition, phlorizin improved the HFFD-induced decrease in synaptic plasticity, neuroinflammation, and excessive activation of microglia in the hippocampus. Transcriptomics analysis shows that the protective effect of phlorizin on cognitive impairment was associated with increased expression of neurotransmitters and synapse-related genes in the hippocampus. Phlorizin treatment alleviated colon microbiota disturbance, mainly manifested by an increase in gut microbiota diversity and the abundance of short-chain fatty acid (SCFA)-producing bacteria. The level of microbial metabolites, including SCFA, inosine 5'-monophosphate (IMP), and D (-)-beta-hydroxybutyric acid (BHB) were also significantly increased after phlorizin treatment. Moreover, integrating multiomics analysis observed tight connections between phlorizin-regulated genes, microbiota, and metabolites. Furthermore, removal of the gut microbiota via antibiotics treatment diminished the protective effect of phlorizin against HFFD-induced cognitive impairment, underscoring the critical role of the gut microbiota in mediating cognitive behavior. Importantly, supplementation with SCFA and BHB alone mimicked the regulatory effects of phlorizin on cognitive function. Conclusions: These results indicate that gut microbiota and their metabolites mediate the ameliorative effect of phlorizin on HFFD-induced cognitive impairment. Therefore, phlorizin can be used as an easy-to-implement nutritional therapy to prevent and alleviate metabolism-related neurodegenerative diseases by targeting the regulation of the microbiome-gut-brain axis.
Project description:We studied the effect of dietary fat type, varying in polyunsaturated/saturated fatty acid ratio's (P/S) on development of metabolic syndrome. C57Bl/6J mice were fed purified high-fat diets (45E% fat) containing palm oil (HF-PO; P/S 0.4), olive oil (HF-OO; P/S 1.1) or safflower oil (HF-SO; P/S 7.8) for 8 weeks. A low-fat palm oil diet (LF-PO; 10E% fat) was used as a reference. Additionally, we analyzed diet-induced changes in gut microbiota composition and mucosal gene expression. The HF-PO diet induced a higher body weight gain and liver triglyceride content compared to the HF-OO, HF-SO or LF-PO diet. In the intestine, the HF-PO diet reduced microbial diversity and increased the Firmicutes/Bacteroidetes ratio. Although this fits a typical obesity profile, our data clearly indicate that an overflow of the HF-PO diet to the distal intestine, rather than obesity itself, is the main trigger for these gut microbiota changes. A HF-PO diet-induced elevation of lipid metabolism-related genes in the distal small intestine confirmed the overflow of palm oil to the distal intestine. Some of these lipid metabolism-related genes were previously already associated with the metabolic syndrome. In conclusion, our data indicate that saturated fat (HF-PO) has a more stimulatory effect on weight gain and hepatic lipid accumulation than unsaturated fat (HF-OO and HF-SO). The overflow of fat to the distal intestine on the HF-PO diet induced changes in gut microbiota composition and mucosal gene expression. We speculate that both are directly or indirectly contributive to the saturated fat-induced development of obesity and hepatic steatosis. Keywords: Diet intervention study Nine-week-old C57Bl/6J mice were fed a low-fat diet (LF-PO) and three different types of high-fat diet, based on palm oil (HF-PO; P/S1.0), olive oil (HF-OO; P/S4.6) and safflower oil (HF-SO; P/S10.1) for 8 weeks. Body weight was recorded weekly and after 7 weeks of diet intervention an oral glucose tolerance test was performed. After 2 weeks of diet intervention, 6 mice per high-fat diet group were anaesthetized with a mixture of isofluorane (1.5%), nitrous oxide (70%) and oxygen (30%) and the small intestines were excised. Adhering fat and pancreatic tissue were carefully removed. The small intestines were divided in three equal parts along the proximal to distal axis (SI 1, SI 2 and SI 3) and microarray analysis was performed on mucosal scrapings.
Project description:We studied the effect of dietary fat type, varying in polyunsaturated/saturated fatty acid ratio's (P/S) on development of metabolic syndrome. C57Bl/6J mice were fed purified high-fat diets (45E% fat) containing palm oil (HF-PO; P/S 0.4), olive oil (HF-OO; P/S 1.1) or safflower oil (HF-SO; P/S 7.8) for 8 weeks. A low-fat palm oil diet (LF-PO; 10E% fat) was used as a reference. Additionally, we analyzed diet-induced changes in gut microbiota composition and mucosal gene expression. The HF-PO diet induced a higher body weight gain and liver triglyceride content compared to the HF-OO, HF-SO or LF-PO diet. In the intestine, the HF-PO diet reduced microbial diversity and increased the Firmicutes/Bacteroidetes ratio. Although this fits a typical obesity profile, our data clearly indicate that an overflow of the HF-PO diet to the distal intestine, rather than obesity itself, is the main trigger for these gut microbiota changes. A HF-PO diet-induced elevation of lipid metabolism-related genes in the distal small intestine confirmed the overflow of palm oil to the distal intestine. Some of these lipid metabolism-related genes were previously already associated with the metabolic syndrome. In conclusion, our data indicate that saturated fat (HF-PO) has a more stimulatory effect on weight gain and hepatic lipid accumulation than unsaturated fat (HF-OO and HF-SO). The overflow of fat to the distal intestine on the HF-PO diet induced changes in gut microbiota composition and mucosal gene expression. We speculate that both are directly or indirectly contributive to the saturated fat-induced development of obesity and hepatic steatosis. Keywords: Diet intervention study
Project description:Dietary lipids can affect metabolic health through gut microbiota-mediated mechanisms, but the influence of lipid-microbiota interaction on liver steatosis is unknown. We investigated the effect of dietary lipid composition on human microbiota in an observational study and combined diet experiments with microbiota transplants to study lipid-microbiota interactions and liver status in mice. In humans, low intake of saturated fatty acids (SFA) was associated with increased microbial diversity independent of fiber intake. In mice, cecum levels of SFA correlated negatively with microbial diversity and were associated with a shift in butyrate and propionate producers. Mice fed poorly absorbed SFA had improved metabolism and liver status. These features were transmitted by microbial transfer. Diets enriched in n-6- and/or n-3-polyunsaturated fatty acids were protective against steatosis but had minor influence on the microbiota. In summary, we find that unabsorbed SFA correlate with microbiota features that may be targeted to decrease liver steatosis.
Project description:Gut microbiota dysbiosis characterizes systemic metabolic alteration, yet its causality is debated. To address this issue, we transplanted antibiotic-free conventional wild-type mice with either dysbiotic (“obese”) or eubiotic (“lean”) gut microbiota and fed them either a NC or a 72%HFD. We report that, on NC, obese gut microbiota transplantation reduces hepatic gluconeogenesis with decreased hepatic PEPCK activity, compared to non-transplanted mice. Of note, this phenotype is blunted in conventional NOD2KO mice. By contrast, lean microbiota transplantation did not affect hepatic gluconeogenesis. In addition, obese microbiota transplantation changed both gut microbiota and microbiome of recipient mice. Interestingly, hepatic gluconeogenesis, PEPCK and G6Pase activity were reduced even once mice transplanted with the obese gut microbiota were fed a 72%HFD, together with reduced fed glycaemia and adiposity compared to non-transplanted mice. Notably, changes in gut microbiota and microbiome induced by the transplantation were still detectable on 72%HFD. Finally, we report that obese gut microbiota transplantation may impact on hepatic metabolism and even prevent HFD-increased hepatic gluconeogenesis. Our findings may provide a new vision of gut microbiota dysbiosis, useful for a better understanding of the aetiology of metabolic diseases. all livers are from NC-fed mice only.
Project description:Microbiota from rats fed with wheat aleurone and plant omega fatty acids In this study we investigated how an AX-rich WA and ALA from linseed oil (LO) modulate the gut microbiota of rats. Wistar rats were fed a standard diet and received either an iso-energetic control oil (PO), control oil + aleurone (A+PO), linseed oil (LO) or linseed oil + aleurone (A+LO) during 12 weeks. Feacal samples were recovered after the 12 week treatments. DNA extractions were performed using using the Qiagen's DNA Stool Kit (Qiagen, West Sussex, UK). 10ng of DNA template were amplified by PCR (16S gene) and purified using Qiagen's Qiaquick PCR purification kit (Qiagen, West Sussex, UK). 1ug of purified PCR product were labelled with either Cy3 or Cy5 using Genomic DNA ULS Labelling kit (Agilent Technologies, Palo Alto, CA). 250ng of labelled DNA were hybridized on the microarray for 24h at 65M-BM-0C. Washings were performed as recommended by the manufacturer. Microarray scanning was performed on a Surescan Microarray scanner (Agilent Technologies, Palo Alto, CA). Data were extracted using the Feature extraction software (Agilent Technologies, Palo Alto, CA). The retained intensity value for each probe was the ratio between the spotM-bM-^@M-^Ys median intensity signals and the median of background signals. A 13 chip study was realized to analyze the feacal microbiota of rats treated with either an iso-energetic control oil (PO), control oil + aleurone (A+PO), linseed oil (LO) or linseed oil + aleurone (A+LO) during 12 weeks. Each microarray corresponding to hybridization with 250ng of labelled 16S rRNA gene amplicons from 2 rat DNA faecal samples. Microbiota structure and diversity were assessed using the HuGChip (Tottey et al., 2013). Each probe (4441) was synthetized in three replicates. On the same array, 2 different samples were hybridized. One labelled with the Cy3 dye and one with the Cy5 dye. The results were processed as single channel (13 raw data files available on Series records for 25 samples).