Project description:Gut dysbiosis is closely involved in the pathogenesis of inflammatory bowel disease (IBD). However, it remains unclear whether IBD-associated gut dysbiosis plays a primary role in disease manifestation or is merely secondary to intestinal inflammation. Here, we established a humanized gnotobiotic (hGB) mouse system to assess the functional role of gut dysbiosis associated with two types of IBD - Crohn's disease (CD) and ulcerative colitis (UC). In order to explore the functional impact of dysbiotic microbiota in IBD patients on host immune responses, we analyzed gene expression profiles in colonic mucosa of hGB mice colonized with healty (HC), CD, and UC microbiota.
Project description:Gut microbiota in short bowel syndrome
| PRJDB4453 | ENA
Project description:EMG produced TPA metagenomics assembly of the Severe gut microbiota dysbiosis is associated with poor growth in patients with short bowel syndrome (human gut metagenome) data set.
Project description:Dysbiosis is linked to the pathogenesis of inflammatory bowel disease. Although there is a lot of interest in restoring the balance, we do not understand the effects of dysbiosis, especially on epithelial cells. In addition, we know that epithelial cells from IBD patients maintain intrinsic defects. For that reason, we aimed to unravel if epithelial cells of UC patients are more sensitive towards microbiota stimulation, compared to non-IBD controls. In addition, we analyzed the effect of UC microbiota or microbiota of healthy donors towards epithelial cells. Confluent organoid derived monolayers of 8 UC patients and 8 non-IBD controls were co-cultured for 6 hours with microbiota (3.10^8 cells) , derived of a healthy donor (HD) or UC patients. If applicable, epithelial cells were first cultured for 24 hours with an inflammatory mix (100 ng/mL TNFα, 20 ng/mL IL1β, 1 µg/mL Flagellin). The inflammatory stimulation was continued in the 6 hours co-culture.Transcriptomic expression of epithelial cells was evaluated after 6 hours co-culture by Truseq for Illumina.
Project description:Morphine and its pharmacological derivatives are the most prescribed analgesics for moderate to severe pain management. However, chronic use of morphine reduces pathogen clearance and induces bacterial translocation across the gut barrier. The enteric microbiome has been shown to play a critical role in the preservation of the mucosal barrier function and metabolic homeostasis. Here, we show for the first time, using bacterial 16s rDNA sequencing, that chronic morphine treatment significantly alters the gut microbial composition and induces preferential expansion of the gram-positive pathogenic and reduction of bile-deconjugating bacterial strains. A significant reduction in both primary and secondary bile acid levels was seen in the gut, but not in the liver with morphine treatment. Morphine induced microbial dysbiosis and gut barrier disruption was rescued by transplanting placebo-treated microbiota into morphine-treated animals, indicating that microbiome modulation could be exploited as a therapeutic strategy for patients using morphine for pain management. In this study, we establish a link between the two phenomena, namely gut barrier compromise and dysregulated bile acid metabolism. We show for the first time that morphine fosters significant gut microbial dysbiosis and disrupts cholesterol/bile acid metabolism. Changes in the gut microbial composition is strongly correlated to disruption in host inflammatory homeostasis13,14 and in many diseases (e.g. cancer/HIV infection), persistent inflammation is known to aid and promote the progression of the primary morbidity. We show here that chronic morphine, gut microbial dysbiosis, disruption of cholesterol/bile acid metabolism and gut inflammation; have a linear correlation. This opens up the prospect of devising minimally invasive adjunct treatment strategies involving microbiome and bile acid modulation and thus bringing down morphine-mediated inflammation in the host.
Project description:Microbial dysbiosis has been identified in adult inflammatory bowel disease (IBD) patients. However, microbial composition and functional interplay between host genetics and microorganisms in early IBD onset remain poorly defined. Here, we identified and demonstrated the causal effect of Atopobium parvulum and the gut microbiota in pediatric IBD. Microbiota and proteomic profiling revealed that the abundance of A. parvulum, a potent H2S producer, was associated with increased disease severity and a concurrent reduction in the expression of the host H2S detoxification pathway. In the Il10-/- mouse model of inflammation, A. parvulum induced severe pancolitis that was dependent on the presence of the gut microbiota. In addition, we demonstrated that administration of bismuth, an H2S scavenger, prevented A. parvulum-induced colitis. Our findings identified Atopobium parvulum as a major mediator of inflammation severity, and revealed an alteration of the balance between the production and detoxification of H2S in the gastrointestinal tract.
Project description:Compositional changes in the microbiota (dysbiosis) may be a basis for Irritable Bowel Syndrome (IBS) but biomarkers are currently unavailable to direct microbiota-directed therapy. We therefore examined whether changes in fecal β-defensin could be a marker of dysbiosis in a murine model. Experimental dysbiosis was induced using four interventions relevant to IBS: a mix of antimicrobials, westernized diets (high-fat/high-sugar and, high salt diets), or mild restraint stress. Fecal mouse β-defensin-3 and 16S rRNA-based microbiome profiles were assessed at baseline, during and following these interventions. Each intervention, except for mild restraint stress, altered compositional and diversity profiles of the microbiota. Exposure to antimicrobials or a high-fat/high-sugar diet, but not mild restraint stress, resulted in decreased fecal β-defensin-3 compared to baseline. In contrast, exposure to the high salt diet increased β-defensin-3 compared to baseline but this was not accompanied by discernible inflammatory changes in the host.
Project description:Irritable Bowel Syndrome (IBS) is a disorder of the gut-brain axis, characterized by altered gut function and frequent psychiatric co-morbidity. Although altered intestinal microbiome profiles have been documented, their relevance to the clinical expression of IBS is unknown. To evaluate a functional role of the microbiota, we colonized germ-free mice with fecal microbiota from healthy controls or IBS patients with accompanying anxiety, and monitored gut function and behavior. Mouse microbiota profiles clustered according to their human donors. Despite having taxonomically similar composition as controls, mice with IBS microbiota had distinct serum metabolomic profiles related to neuro- and immunomodulation. Mice with IBS, but not control microbiota, exhibited faster gastrointestinal transit, intestinal barrier dysfunction, innate immune activation and anxiety-like behavior. These results support the notion that the microbiota contributes to both intestinal and behavioral manifestations of IBS and rationalize the use of microbiota-directed therapies in ameliorating IBS.