Project description:HuMiChip2 was applied to analyze perform both strain-level identification and the functional profiling of human gut microbiomes from alcoholic cirrhosis patients and healthy individuals with alcohol abuse.
Project description:We have previously demonstrated that the gut microbiota can play a role in the pathogenesis of conditions associated with exposure to environmental pollutants. It is well accepted that diets high in fermentable fibers such as inulin can beneficially modulate the gut microbiota and lessen the severity of pro-inflammatory diseases. Therefore, we aimed to test the hypothesis that hyperlipidemic mice fed a diet enriched with inulin would be protected from the pro-inflammatory toxic effects of PCB 126.
Project description:The understanding of the effects of compounds on the gut microbiome is limited and in particular we don’t know whether structurally similar compounds have similar or distinct effects on the gut microbiome. Here we selected berberine (BBR), an isoquinoline quaternary alkaloid, and sixteen structural analogues, and evaluated their effects on in vitro cultured individual gut microbiomes. The responses of the individual microbiomes were evaluated by metaproteomic profiles and by assessing butyrate production. BBR and eight analogues led to changes in proteins involved in microbial defense and stress responses, and enrichment of proteins from Verrumicrobia, Proteobacteria and Bacteroides phyla. It also led to a decrease in proteins from the Firmicutes phylum and its Clostridiales order which correlated to decrease proteins involved in the butyrate production pathway and butyrate concentration. Three of the compounds, Sanguinarine, Chelerythrine and Ethoxysanguinarine activated bacterial protective mechanisms, enriched Proteobacteria, increased opacity proteins and markedly reduced butyrate production. Dihydroberberine had a similar function to BBR in enriching the Akkermansia genus. In addition, it showed less overall adverse impacts on the functionality of the gut microbiome, including a better maintenance of the butyrate level. Our study shows that ex vivo microbiome assay can assess differential regulating effects of compounds with subtle differences and reveals that compound analogues can have distinct effects on the microbiome.
Project description:Giant panda are carnivorous bears which feed almost exclusively on plant biomass (i.e. bamboo). The potential contribution of its gut microbiome to lignocellulose degradation has been mostly investigated with cultivation-independent approaches. Recently, we reported on the first lab-scale cultivation of giant panda gut microbiomes and described their actual fermentation capacity. Fermentation of bamboo leaf using green dung resulted in a neutral pH, the main products being ethanol, lactate and H2. Fermentation of bamboo pith using yellow dung resulted in an acidic pH, the main product being lactate. Here, we cultivated giant panda gut microbiomes to test 1) the impact of mixed dung as inoculum; 2) the fermentation capacity of solid lignocellulose as opposed to organics-rich biofluids in the dung; 3) the artificial shift of pH from neutral to acidic on bamboo leaf fermentation. Our results indicate that i) gut microbiomes fermentation of solid lignocellulose contributes up to a maximum of 1/3 even in the presence of organics-rich biofluids; ii) alcohols are an important product of bamboo leaf fermentation at neutral pH; iii) aside hemicellulose, gut microbiomes may degrade plant cell membranes to produce glycerol; iv) pH, rather than portion of bamboo, ultimately determines fermentation profiles and gut microbiome assemblage.
Project description:Resistant starches (RS) are dietary compounds processed by the gut microbiota into metabolites, such as butyrate, that are beneficial to the host. The production of butyrate by the microbiome appears to be affected by the plant source and type of RS as well as the individual’s microbiota. In this study, we used in vitro culture and metaproteomic methods to explore the consistency and variations in individual microbiome's functional responses to three types of RS - RS2(Hi Maize 260), RS3(Novelose 330) and RS4(Fibersym RW). Results showed that RS2 and RS3 significantly altered the levels of protein expression in the individual gut microbiomes, while RS4 did not result in significant protein changes. Significantly elevated protein groups were enriched in carbohydrate metabolism and transport functions of families Eubacteriaceae, Lachnospiraceae and Ruminococcaceae. In addition, Bifidobacteriaceae was significantly increased in response to RS3. We also observed taxon-specific enrichments of starch metabolism and pentose phosphate pathways corresponding to this family. Functions related to starch utilization, ABC transporters and pyruvate metabolism pathways were consistently increased in the individual microbiomes in response to RS2 and RS3; in contrast, the downstream butyrate producing pathway response varied. Our study confirm that different types of RS have markedly variable functional effects on the human gut microbiome, and also found considerable inter-individual differences in microbiome pathway responses.
Project description:RNA was extracted from the meninges of mice from either Specific pathogen free or Germ free facilities or from the offspring of mice reconstituted with different human microbiomes.
Project description:We transplanted gut microbiota via fecal transfer from TD and ASD children into germ-free wild-type mice, and reveal that colonization with ASD microbiomes induces hallmark changes in sociability, vocalization, and stereotypies. The brains of mice receiving gut microbiota from ASD individuals display alternative splicing patterns for genes dysregulated in the human ASD brain.
Project description:Although gut microbiomes are generally symbiotic or commensal, some of microbiomes become pathogenic under certain circumstances, which is one of key processes of pathogenesis. However, the factors involved in these complex gut-microbe interactions are largely unknown. Here we show that bacterial nucleoside catabolism using gut luminal uridine is required to boost inter-bacterial communications and gut pathogenesis in Drosophila. We found that uridine-derived uracil is required for DUOX-dependent ROS generation on the host side, whereas uridine-derived ribose induces quorum sensing and virulence gene expression on the bacterial side. Importantly, genetic ablation of bacterial nucleoside catabolism is sufficient to block the commensal-to-pathogen transition in vivo. Furthermore, we found that major commensal bacteria lack functional nucleoside catabolism, which is required to achieve gut-microbe symbiosis. The discovery of a novel role of bacterial nucleoside catabolism will greatly help to better understand the molecular mechanism of the commensal-to-pathogen transition in different contexts of host-microbe interactions.