Project description:Early-weaning-induced stress causes diarrhea, thereby reduces growth performance of piglets. Gut bacterial dysbiosis emerges as a leading cause of post-weaning diarrhea. The present study was aimed to investigate the effect of capsulized fecal microbiota transportation (FMT) on gut bacterial community, immune response and gut barrier function of weaned piglets. Thirty-two were randomly divided into two groups fed with basal diet for 21 days. Recipient group was inoculated orally with capsulized fecal microbiota of health Tibetan pig daily morning during whole period of trial, while control group was given orally empty capsule. The results showed that the F/G ratio, diarrhea ratio, diarrhea index, and histological damage score of recipient piglets were significantly decreased. FMT treatment also significantly increased the colon length of piglets. Furthermore, the relative abundances of Firmicutes, Euryarchaeota, Tenericutes, Lactobacillus, Methanobrevibacter and Sarcina in colon of recipient piglets were increased, and the relative abundances of Campylobacter, Proteobacteria, and Melainabacteria were significantly decreased compared with control group.
Project description:Background & Aims: The complex interactions between diet and the microbiota that influence mucosal inflammation and inflammatory bowel disease are poorly understood. Experimental colitis models provide the opportunity to control and systematically perturb diet and the microbiota in parallel to quantify the contributions between multiple dietary ingredients and the microbiota on host physiology and colitis. Methods: To examine the interplay of diet and the gut microbiota on host health and colitis, we fed over 40 different diets with varied macronutrient sources and concentrations to specific pathogen free or germ free mice either in the context of healthy, unchallenged animals or dextran sodium sulfate colitis model. Results: Diet influenced physiology in both health and colitis across all models, with the concentration of protein and psyllium fiber having the most profound effects. Increasing dietary protein elevated gut microbial density and worsened DSS colitis severity. Depleting gut microbial density by using germ-free animals or antibiotics negated the effect of a high protein diet. Psyllium fiber influenced host physiology and attenuated colitis severity through microbiota-dependent and microbiota-independent mechanisms. Combinatorial perturbations to dietary protein and psyllium fiber in parallel explain most variation in gut microbial density, intestinal permeability, and DSS colitis severity, and changes in one ingredient can be offset by changes in the other. Conclusions: Our results demonstrate the importance of examining complex mixtures of nutrients to understand the role of diet in intestinal inflammation. Keywords: IBD; Diet; Microbiota; Mouse Models; Systems Biology
Project description:Research findings of the past decade have highlighted the gut as the main site of action of the oral antihyperglycemic agent metformin despite its pharmacological role in the liver. Extensive evidence supports metformin’s modulatory effect on the composition and function of gut microbiota, nevertheless, the underlying mechanisms of the host responses remain elusive. Our study aimed to evaluate metformin-induced alterations in the intestinal transcriptome profiles at different metabolic states. The high-fat diet-induced type 2 diabetes mouse model of both sexes was developed in a randomized block experiment and bulk RNA-Seq of the ileum tissue was the method of choice for comparative transcriptional profiling after metformin intervention for ten weeks. We found a prominent transcriptional effect of the diet itself with comparatively fewer genes responding to metformin intervention. The overrepresentation of immune-related genes was observed, including pronounced metformin-induced upregulation of immunoglobulin heavy-chain variable regioncoding Ighv1-7 gene in both high-fat diet and control diet-fed animals, supporting the contribution of intestinal immunoglobulin responses. Finally, we provide evidence of the downregulation NF-kappa B signaling pathway in the small intestine of both hyperglycemic and normoglycemic animals after metformin treatment. Moreover, our data pinpoint the gut microbiota as a crucial component in the metformin-mediated downregulation of NF-kappaB signaling evidenced by a positive correlation between the Rel and Rela gene expression levels and abundances of Parabacteroides distasonis, Bacteroides spp., and Lactobacillus spp. in the gut microbiota of the same animals.
Project description:The gut microbiota composition is unique to every individual but is shaped by common factors including diet, lifestyle, medication use, early-life determinants, living environment or genetics. Most of these factors may be influenced by ethnicity. This study explored variations in fecal microbiota composition in 6048 individuals with different ethnic backgrounds living in the same geographical area (Amsterdam, the Netherlands).
Project description:Pu-erh tea has attracted increasing attention worldwide because of its special flavor and health effects, but its impact on composition and function of the gut microbiota remains unclear. The aim of this study was to investigate effects of aqueous extracts of fermented (ripe) and non-fermented (raw) Pu-erh teas on the composition and function of intestinal microbiota of rats with diet-induced obesity. We conducted a comparative metagenomic and metaproteomic investigation of the microbial communities in cecal samples taken from obese rats administrated with or without extracts of raw and ripe Pu-erh tea. By analyzing the composition and diversity of 16S rRNA amplicons and expression profiles of 814 distinct proteins, we found that, despite differences in the chemical compositions of the raw and ripe Pu-erh tea, administration of either at two different doses (0.15 and 0.40 g/Kg body weight), significantly (P<0.05) increased community diversity, and changed the composition of the cecal microbiota by increasing the relative abundances of Firmicutes and decreasing those of Bacteroidetes. Community metabolic processes including sucrose metabolism, glycolysis, syntheses of proteins, rRNA and antibiotics were significantly (P<0.05), or had a tendency (0.10<P<0.05) to be, promoted by enriching relevant enzymes. Furthermore, evidences from population, molecular and metabolic levels have shown that polyphenols of raw Pu-erh tea and their metabolites can promote potentially the growth of Akkermansia municiphila by stimulating the type II and III secretion system protein, elongation factor Tu, and glyceraldehyde-3-phosphate dehydrogenase. This study has provided new evidences for the prebiotic effects of Pu-erh tea.
Project description:The human gut microbiota is a metabolic organ whose cellular composition is determined by a dynamic process of selection and competition. To identify microbial genes required for establishment of human symbionts in the gut, we developed an approach (insertion-sequencing, or INSeq) based on a mutagenic transposon that allows capture of adjacent chromosomal DNA to define its genomic location. We used massively parallel sequencing to monitor the relative abundance of tens of thousands of transposon mutants of a saccharolytic human gut bacterium, Bacteroides thetaiotaomicron, as they established themselves in wild-type and immunodeficient gnotobiotic mice, in the presence or absence of other human gut commensals. In vivo selection transforms this population, revealing functions necessary for survival in the gut: we show how this selection is influenced by community composition and competition for nutrients (vitamin B12). INSeq provides a broadly applicable platform to explore microbial adaptation to the gut and other ecosystems. Keywords: Other 57 samples analyzed, 1 of these is the reference (input) sample
Project description:The ketogenic diet has long been used to treat epilepsy, but its mechanism is not yet clearly understood. To explore the potential mechanism, the changes in gene expression induced by the ketogenic diet in the rat kainic acid (KA) epilepsy model were analyzed. Two-condition experiment, Normal diet-fed rat brain vs. Ketogenic diet-fed rat brain. Duplicate per array
Project description:Gut microbiota is involved in metabolic disorders. However, microbiome-based therapeutic interventions are not always effective, which might be due to interference of the host factors. Here, we first identified a strong positive correlation between OPN levels and BMI in humans. Next, we confirmed that OPN could aggravate high-fat diet induced metabolic disorders in mice. Importantly, we found that fecal microbiota transplantation from OPN-deficient mice significantly alleviated metabolic disorders in WT mice. OPN directly induces remodeling of the gut microbiota both in vitro and in vivo. These findings indicate that OPN could contribute to metabolic disorders by inducing an alteration of gut microbiota. OPN regulated the relative abundance of Lactobacillus by decreasing the adhesion of Lactobacillus to intestinal epithelial cells through Notch signaling pathway. These data identify OPN may serve as a potential pharmaceutical target for weight control and metabolic disorders treatment.
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.