Project description:Gut microbiota were assessed in 540 colonoscopy-screened adults by 16S rRNA gene sequencing of stool samples. Investigators compared gut microbiota diversity, overall composition, and normalized taxon abundance among these groups.
Project description:Significant gut microbiota heterogeneity exists amongst UC patients though the clinical implications of this variance are unknown. European and South Asian UC patients exhibit distinct disease risk alleles, many of which regulate immune function and relate to variation in gut microbiota β-diversity. We hypothesized ethnically distinct UC patients exhibit discrete gut microbiotas with unique luminal metabolic programming that influence adaptive immune responses and relate to clinical status. Using parallel bacterial 16S rRNA and fungal ITS2 sequencing of fecal samples (UC n=30; healthy n=13), we corroborated previous observations of UC-associated depletion of bacterial diversity and demonstrated significant gastrointestinal expansion of Saccharomycetales as a novel UC characteristic. We identified four distinct microbial community states (MCS 1-4), confirmed their existence using microbiota data from an independent UC cohort, and show they co-associate with patient ethnicity and degree of disease severity. Each MCS was predicted to be uniquely enriched for specific amino acid, carbohydrate, and lipid metabolism pathways and exhibited significant luminal enrichment of metabolic products from these pathways. Using a novel in vitro human DC/T-cell assay we show that DC exposure to patient fecal water led to MCS -specific changes in T-cell populations, particularly the Th1:Th2 ratio, and that patients with the most severe disease exhibited the greatest Th2 skewing. Thus, based on ethnicity, microbiome composition, and associated metabolic dysfunction, UC patients may be stratified in a clinically and immunologically meaningful manner, providing a platform for the development of FMC-focused therapy. Fecal microbiome was assessed with Affymetrix PhyloChip arrays from patients with ulcerative colitis and healthy controls.
Project description:Persistent mucosal inflammation and microbial infection are characteristic of Chronic Rhinosinusitis (CRS). Though mucosal microbiota dysbiosis is a characteristic feature of other chronic inflammatory diseases, the relationship between sinus microbiota composition and CRS is unknown. Here we demonstrate, using comparative microbiome profiling of a cohort of CRS patients and healthy subjects, that the sinus microbiota of CRS patients exhibit significantly reduced bacterial diversity. Characteristic of this community collapse is the depletion of multiple, phylogenetically distinct, Lactic Acid Bacteria and the concomitant increase in relative abundance of a single species, Corynebacterium tuberculostearicum. Recapitulating the conditions observed in our human cohort in a murine model confirmed the pathogenic potential of C. tuberculostearicum and the critical necessity for a replete mucosal microbiota to protect against this species. Moreover, we provide evidence that Lactobacillus sakei, identified from our comparative microbiome analyses as a potentially protective species, affords defense against C. tuberculostearicum sinus infection, even in the context of a depleted sinus bacterial community. These studies demonstrate that sinus mucosal health is highly dependent on the composition of the resident microbiota, and identifies a new sino-pathogen and a strong bacterial candidate for therapeutic intervention. A total of 14 samples were profiled for microbiome composition: 7 from non-sinusitis patients, and 7 from patients with clinically diagnosed chronic sinusitis.
Project description:We applied metagenomic shotgun sequencing to investigate the effects of ZEA exposure on the change of mouse gut microbiota composition and function.
Project description:Changes in microbiome composition have been associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we infused gut organ cultures with longitudinal microbiota samples collected from therapy-naïve irritable bowel syndrome (IBS) patients under low-FODMAP (fermentable Oligo-, Di-, Mono-saccharides and Polyols) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene-sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a unique pathway discovery approach for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of low-FODMAP diet and reinforce the potential feasibility of microbiome based-therapies in IBS.
Project description:Changes in microbiome composition have been associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we infused gut organ cultures with longitudinal microbiota samples collected from therapy-naïve irritable bowel syndrome (IBS) patients under low-FODMAP (fermentable Oligo-, Di-, Mono-saccharides and Polyols) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene-sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a unique pathway discovery approach for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of low-FODMAP diet and reinforce the potential feasibility of microbiome based-therapies in IBS.
Project description:Changes in microbiome composition have been associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we infused gut organ cultures with longitudinal microbiota samples collected from therapy-naïve irritable bowel syndrome (IBS) patients under low-FODMAP (fermentable Oligo-, Di-, Mono-saccharides and Polyols) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene-sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a unique pathway discovery approach for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of low-FODMAP diet and reinforce the potential feasibility of microbiome based-therapies in IBS.
Project description:Maternal secretor status is one of the determinants of human milk oligosaccharides (HMOs) composition, which in turn changes the gut microbiota composition of infants. To understand if this change in gut microbiota impacts immune cell composition, intestinal morphology and gene expression, day 21-old germ-free mice were transplanted with fecal microbiota from infants whose mothers were either secretors (SMM) or non-secretors (NSM) or from infants consuming dairy-based formula (MFM). For each group, one set of mice was supplemented with HMOs. HMO supplementation did not significantly impact the microbiota diversity however, SMM mice had higher abundance of genus Bacteroides, Bifidobacterium, and Blautia, whereas, in the NSM group, there were higher abundance of Akkermansia, Enterocloster, and Klebsiella. In MFM, gut microbiota was represented mainly by Parabacteroides, Ruminococcaceae_unclassified, and Clostrodium_sensu_stricto. In mesenteric lymph node, Foxp3+ T cells and innate lymphoid cells type 2 (ILC2) were increased in MFM mice supplemented with HMOs while in the spleen, they were increased in SMM+HMOs mice. Similarly, serum immunoglobulin A (IgA) was also elevated in MFM+HMOs group. Distinct global gene expression of the gut was observed in each microbiota group, which was enhanced with HMOs supplementation. Overall, our data shows that distinct infant gut microbiota due to maternal secretor status or consumption of dairy-based formula and HMO supplementation impacts immune cell composition, antibody response and intestinal gene expression in a mouse model.
Project description:Introduction: Chronic sleep fragmentation (SF) is prevalent in contemporary human society, highlighting detrimental effects on glucose metabolism and adipose tissue morphology, which is closely linked to gut microbiota composition. However, it remains unclear whether sleep recovery (SR) after prolonged SF can ameliorate glucose metabolism, influence the transcriptome of inguinal white adipose tissue (iWAT), and whether these effects align with alterations in the gut microbiota. Methods: Mice were subjected to 8 weeks of SF and subsequently allowed 2 weeks of SR. We assessed glucose tolerance through intraperitoneal glucose tolerance tests (ipGTT), analyzed gut microbiota via 16s rDNA amplicon sequencing, and examined transcriptomic alterations in iWAT using RNA sequencing. Results: Despite the two-week SR following chronic SF, significant glucose intolerance persisted, accompanied by subtle shifts in the gut microbiota and alterations in gene expression within iWAT. The top hub genes Ncapg, Cenpe, and Tik were identified from the protein-protein interaction network. Conclusion: Even followed by a brief period of SR, prolonged SF still led to ongoing glucose intolerance and alterations in the adipose tissue transcriptome in mice. These changes were intertwined with modifications in the gut microbiome. The shifts in gut microbiota may play a pivotal role in understanding the sustained negative effects of SF.
Project description:The gut microbiota has been implicated in obesity and cardiometabolic diseases, although evidence in humans is scarce. We investigated how gut microbiota manipulation by antibiotics (7-day administration of amoxicillin, vancomycin, or placebo) affects host metabolism in 57 obese, prediabetic men. Vancomycin, but not amoxicillin, decreased bacterial diversity and reduced Firmicutes involved in short-chain fatty acid and bile acid metabolism, concomitant with altered plasma and/or fecal metabolite concentrations. Adipose tissue gene expression of oxidative pathways was upregulated by antibiotics, whereas immune-related pathways were downregulated by vancomycin. Antibiotics did not affect tissue-specific insulin sensitivity, energy/substrate metabolism, postprandial hormones and metabolites, systemic inflammation, gut permeability, and adipocyte size. Importantly, energy harvest, adipocyte size, and whole-body insulin sensitivity were not altered at 8-week follow-up, despite a still considerably altered microbial composition, indicating that interference with adult microbiota by 7-day antibiotic treatment has no clinically relevant impact on metabolic health in obese humans. This randomized, placebo-controlled, double-blind study had a 3-armed parallel design. Overweight/obese participants were randomized to oral intake of amoxicillin, vancomycin or placebo for 7 consecutive days. After an overnight fast, subcutaneous adipose tissue biopsies were taken that were subjected to gene expression profiling by array.