RNA-Sequence analysis of enteroids incubating with Bifidobacterium longum

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.