Project description:Recent evidence suggests an important role of the gut microbiome in early life on immune cell entraining. Using two independent transgenic (Tg) lines of Alzheimer’s disease, we have demonstrated that life-long antibiotic (ABX)-perturbation of the gut microbiome is associated with reduced amyloid beta (Ab) plaque pathology and microglial phenotypes in male mice. Furthermore, fecal microbiota transfer (FMT) from age-matched APPPS1-21 Tg mice into long-term ABX-treated male APPPS1-21 mice partially restored amyloidosis and microgliosis, thus establishing causality. in the current studies, we planned to investigate the transcriptome profiles in APPPS1-21 mice treated with short-term abx (PND14-21) compared with vehicle treated groups in genotype-, sex- and time -dependent manner. Most importantly, we also investigated if fecal microbiota transplants from age-matched Tg male mice into short-term abx (PND14-21)-treated male mice restores brain transcriptomes to that of obsreved in vehicle-treated male mice at 9 weeks of age.
Project description:Opioids such as morphine have many beneficial properties as analgesics, however, opioids may induce multiple adverse gastrointestinal symptoms. We have recently demonstrated that morphine treatment results in significant disruption in gut barrier function leading to increased translocation of gut commensal bacteria. However, it is unclear how opioids modulate the gut homeostasis. By using a mouse model of morphine treatment, we studied effects of morphine treatment on gut microbiome. We characterized phylogenetic profiles of gut microbes, and found a significant shift in the gut microbiome and increase of pathogenic bacteria following morphine treatment when compared to placebo. In the present study, wild type mice (C57BL/6J) were implanted with placebo, morphine pellets subcutaneously. Fecal matter were taken for bacterial 16s rDNA sequencing analysis at day 3 post treatment. A scatter plot based on an unweighted UniFrac distance matrics obtained from the sequences at OTU level with 97% similarity showed a distinct clustering of the community composition between the morphine and placebo treated groups. By using the chao1 index to evaluate alpha diversity (that is diversity within a group) and using unweighted UniFrac distance to evaluate beta diversity (that is diversity between groups, comparing microbial community based on compositional structures), we found that morphine treatment results in a significant decrease in alpha diversity and shift in fecal microbiome at day 3 post treatment compared to placebo treatment. Taxonomical analysis showed that morphine treatment results in a significant increase of potential pathogenic bacteria. Our study shed light on effects of morphine on the gut microbiome, and its role in the gut homeostasis.
Project description:A rapid ex vivo microbiome assay and metaproteomics approach was used for rapid evaluation of the cultivability of bio-banked live microbiota, which shows minimal detrimental influences of long-term freezing in deoxygenated glycerol buffer on the cultivability of fecal microbiota.
Project description:We found that low protein diet consumption resulted in decrease in the percentage of normal Paneth cell population in wild type mice, indicating that low protein diet could negatively affect Paneth cell function. We performed fecal microbiota composition profiling. Male mice were used at 4-5 weeks of age. Fecal samples were collected for microbiome analysis.
Project description:In rodents, brown adipose tissue (BAT) contributes to whole body energy expenditure and low BAT activity is related to hepatic fat accumulation, partially attributable to the gut microbiome. Little is known of these relationships in humans. In adults (n=60), we assessed hepatic fat and cold-stimulated BAT activity utilizing magnetic resonance imaging and the gut microbiome with 16S sequencing. We transplanted gnotobiotic mice with feces from humans to assess the transferability of BAT activity and NAFLD through the microbiome. Individuals with NAFLD (n=29) had lower BAT activity than those without and BAT activity was inversely related to hepatic fat. Although the fecal microbiome was different in those with NAFLD, no differences were observed in relation to BAT activity and neither of these phenotypic traits were transmissible through fecal transplant to gnotobiotic mice. Thus, low BAT activity is associated with hepatic steatosis but this is not mediated through the gut microbiota.
Project description:We found that western diet consumption resulted in decrease in the percentage of normal Paneth cell population in wild type mice, indicating that western diet could negatively affect Paneth cell function. Subsequent generations of western diet consumption further reduced percentages of normal Paneth cell population. We performed fecal microbiota composition profiling. Male mice were used at 4-5 weeks of age. Fecal samples were collected for microbiome analysis.
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.