Project description:Although oral administration of Bifidobacterium longum (B. longum) relieves irritable bowel syndrome (IBS) symptoms in a clinical setting, the underlying mechanisms remain undetermined. Herein, we confirmed that B. longum ameliorated defecation habits and alleviated visceral hypersensitivity in water avoidance stress (WAS) rats. Further analysis revealed that B. longum enhanced mucosal repair, promoted the production of lysozyme, and ameliorated microbiota dysbiosis in WAS rats. These activities are all closely correlated with Paneth cell function. In vitro, we incubated primary cultured enteroids with B. longum and found that this bacterium promoted the proliferation of these organoids, which may be attributed to the up-regulated expression of the stem niche factors WNT3A and TGF-β which are serected by the Paneth cells. On the basis of our findings, we propose that B. longum relieves IBS by restoring the antimicrobial activity and stem niche maintenance functions of Paneth cells.
Project description:To understand how glycans influence the growth of probiotic strains in monocultures and communities, we characterized the growth and perform proteome profiling of 3 major probiotics, A. muciniphila (AM) BAA-835, B. breve (BB) JCM1192, and B. longum (BL) JCM1217 in monocultures and co-cultures grown in media with monosaccharides (Glucose & GlcNAc), Mucin, or Arabinoxylan. For the proteomic file annotations, A refers to AM monoculture, B refers to BB monoculture, and L referes to BL monoculture, AL refers to AM+BL co-culture, AB refers to AM+BB co-culture. The letter following the underline specify the media: g refers to Glc+GlcNAc, m refers to mucin, ax refers to arabinoxylan. If there is no underline following the species annotations, the cultures were grown in the base media only. Numbers following the letters specify biological replicates.
Project description:Transcriptional profiling of Bifidobacterium longum mutant versus wt strain in exponentional phase Keywords: Characterization of natural mutant
