Résumé
The current study was designed to evaluate the modulatory effects of paeoniflorin on the dysregulated gut microbiota as well as the disturbed fecal bile acids (BAs) in colitis mice. After approved by Xi'an Jiaotong University Ethics Committees (Approval No. XJTU2019-679), the animals were randomly distributed into the control (Con), colitis, low dose paeoniflorin (PF-L, 25 mg·kg-1·d-1), high dose paeoniflorin (PF-H, 50 mg·kg-1·d-1) and 5-aminosalicylic acid (5-ASA, 50 mg·kg-1·d-1) groups. Colitis was induced by administering 3% (w/v) DSS in drinking water for 7 days. Paeoniflorin and 5-ASA were dissolved in water and administered to the appropriate groups by oral gavage over the 7-day period. The mice were monitored daily, and the disease activity index (DAI) comprising of body weight loss, stool consistency and gross blood was measured. The pathological changes of colon were evaluated by HE staining; the levels of inflammatory cytokines in colonic tissue were determined by ELISA; the gut permeability was measured by FITC-dextran. Microbiota analysis based on 16S rDNA and targeted metabolomics for BAs were used to evaluate the composition of gut microbiota and fecal BAs pool. The results showed that administration of paeoniflorin markedly alleviated the inflammatory response and intestinal barrier dysfunction in DSS-induced colitis. Importantly, these ameliorative effects of paeoniflorin were accompanied by the improvements of disturbed composition of gut microbiota and the dysmetabolism of bile acids in feces. Finally, we performed Spearman's correlation analysis between the fecal BAs and gut microbiota genera, and found that Lactobacillus has a strong positive correlation with DCA and LCA which were reported to confer the beneficial effects of maintaining intestinal homeostasis. Taken together, paeoniflorin might improve the intestinal homeostasis in colitis mice via modulating gut microbiota and fecal BAs metabolism.