Project description:D-galactose orally intake ameliorate DNCB-induced atopic dermatitis by modulating microbiota composition and quorum sensing. The increased abundance of bacteroidetes and decreased abundance of firmicutes was confirmed. By D-galactose treatment, Bacteroides population was increased and prevotella, ruminococcus was decreased which is related to atopic dermatitis.
Project description:Objective: Roux-Y gastric bypass (RYGB) surgery is a last treatment resort to induce substantial and sustained weight loss in severe obesity. The anatomical rearrangement affects the intestinal microbiota but so far, little information is available how it interferes with microbial functionality and microbial-host interaction independent from weight loss. Design: A RYGB rat model was utilized and compared to sham-operated controls which were kept at matched body weight as RYGB animals by food restriction. We assessed microbial taxonomy by 16S rRNA gene sequencing and functional activity by metaproteomics and metabolomics on microbiota samples collected separately from the ileum, the cecum as well as the colon and separately analysed the lumen and mucus associated microbiota. Results: Altered gut architecture in RYGB strongly affected the occurrence of Actinobacteria, especially Bifidobacteriaceae and Proteobacteria which were increased, whereas Firmicutes were decreased, although Streptococcaceae and Clostridium perfringens were observed at higher abundances. A decrease of conjugated as well as secondary bile acids was observed in the RYGB-gut lumen. In addition the arginine biosynthesis pathway in the microbiota was altered, indicated by the changes in abundance of upstream metabolites and enzymes, resulting in lower levels of arginine and higher levels of aspartate in the colon after RYGB. Conclusion: The anatomical rearrangement in RYGB affects microbiota composition and functionality by changes in amino acid and bile acid metabolism, independent of weight loss. The shift in microbiota taxonomic structure after RYGB may be mediated by the resulting change in composition of the bile acid pool in the gut lumen.
Project description:Gut microbiome research is rapidly moving towards the functional characterization of the microbiota by means of shotgun meta-omics. Here, we selected a cohort of healthy subjects from an indigenous and monitored Sardinian population to analyze their gut microbiota using both shotgun metagenomics and shotgun metaproteomics. We found a considerable divergence between genetic potential and functional activity of the human healthy gut microbiota, in spite of a quite comparable taxonomic structure revealed by the two approaches. Investigation of inter-individual variability of taxonomic features revealed Bacteroides and Akkermansia as remarkably conserved and variable in abundance within the population, respectively. Firmicutes-driven butyrogenesis (mainly due to Faecalibacterium spp.) was shown to be the functional activity with the higher expression rate and the lower inter-individual variability in the study cohort, highlighting the key importance of the biosynthesis of this microbial by-product for the gut homeostasis. The taxon-specific contribution to functional activities and metabolic tasks was also examined, giving insights into the peculiar role of several gut microbiota members in carbohydrate metabolism (including polysaccharide degradation, glycan transport, glycolysis and short-chain fatty acid production). In conclusion, our results provide useful indications regarding the main functions actively exerted by the gut microbiota members of a healthy human cohort, and support metaproteomics as a valuable approach to investigate the functional role of the gut microbiota in health and disease.
Project description:Roux-en-Y gastric bypass (RYGB) is highly effective in reversing obesity and associated diabetes. Recent observations in humans suggest a contributing role of increased circulating bile acids in mediating such effects. Here we use a diet-induced obesity mouse model and compared metabolic remission when bile flow was diverted through a gallbladder anastomosis to jejunum, ileum or duodenum (sham control). We found that only bile diversion to the ileum results in physiologic changes similar to RYGB including sustained improvements in weight, glucose tolerance and hepatic steatosis despite differential effects on hepatic gene expression. Circulating free fatty acids and triglycerides decrease while bile acids increase, particularly conjugated tauro-b-muricholic acid, an FXR antagonist. Activity of the hepatic FXR/FGF15 axis was reduced and associated with altered gut microbiota. Thus bile diversion, independent of surgical rearrangement of the gastrointestinal tract, imparts significant weight loss accompanied by improved glucose and lipid homeostasis that are hallmarks of RYGB. Total RNA from n = 5 DIO, n = 4 GB-IL, n = 5 RYGB mice livers was extracted of total RNA and submitted fro RNAseq
Project description:This study aimed to analyze changes in gut microbiota composition in mice after transplantation of fecal microbiota (FMT, N = 6) from the feces of NSCLC patients by analyzing fecal content using 16S rRNA sequencing, 10 days after transplantation. Specific-pathogen-free (SPF) mice were used for each experiments (N=4) as controls.
Project description:Colorectal cancer (CRC) is closely related to gut dysbiosis. We investigated the effects of imbalanced gut microbiota on the progression of intestinal adenoma in Apcmin/+ mice model using fecal microbiota transplantation (FMT). Administration of feces from CRC patients increased tumor proliferation and decreased apoptosis in tumor cells. Abnormal expression of genes related to Wnt-protein binding and lipid metabolic process was observed.
Project description:For phytophagous insects, the efficiency of utilization of hemicellulose and cellulose depends on the gut microbiota. Shifts in environmental and management conditions alter the presence and abundance of plant species which may induce adaptations in the diversity of gut microbiota. To test the adaptation of the microbiota to a shift from a natural diverse to a monocultural meadow with Dactylis glomerata the highly abundant grasshopper species, Chorthippus dorsatus, was taken from the wild and kept in captivity and were fed with Dactylis glomerata for five days. The feces were collected and analyzed by metaproteomics. After the diet shift from a diverse source to the single source, the microbiota composition stays relatively stable. The Bacilli as the group of highest abundance did not change on the functional level. In contrast, pronounced shifts of amino acid and carbohydrate metabolism in Clostridia and Proteobacteria were observed. Hence, the adaptation upon short-term change of food source in this grasshopper species is dominated by functional adaptations and not by shifts in the community structure of the microbiota. This suggests that the microbiota of grasshoppers is capable to cope also with the loss of diverse feeding plants at least for a shorter time period.
Project description:To address the role of gut microbiota in the development of paclitaxel-induced peripheral neuropathy (PIPN), we performed 16S rRNA sequencing analysis of feces samples at 14 days and 28 days after the initiation of paclitaxel or vehicle injections.
Project description:Roux-en-Y gastric bypass (RYGB) is highly effective in reversing obesity and associated diabetes. Recent observations in humans suggest a contributing role of increased circulating bile acids in mediating such effects. Here we use a diet-induced obesity mouse model and compared metabolic remission when bile flow was diverted through a gallbladder anastomosis to jejunum, ileum or duodenum (sham control). We found that only bile diversion to the ileum results in physiologic changes similar to RYGB including sustained improvements in weight, glucose tolerance and hepatic steatosis despite differential effects on hepatic gene expression. Circulating free fatty acids and triglycerides decrease while bile acids increase, particularly conjugated tauro-b-muricholic acid, an FXR antagonist. Activity of the hepatic FXR/FGF15 axis was reduced and associated with altered gut microbiota. Thus bile diversion, independent of surgical rearrangement of the gastrointestinal tract, imparts significant weight loss accompanied by improved glucose and lipid homeostasis that are hallmarks of RYGB.