Fagopyrum cymosum alleviates DSS-induced colitis via ameliorating intestinal barrier function and remolding gut microbiota

Previous research by our team has shown that Fagopyrum cymosum capsules may exert a regulatory effect on intestinal inflammation and immunity through their heat clearing and detoxification effects, and have the potential to become a new approach for treating colitis. In this study, an investigation was conducted to determine whether Fagopyrum cymosum capsules could exert a protective effect on Dextran sulfate sodium (DSS) induced ulcerative colitis rats and to explore its potential mechanisms. The results showed that Fagopyrum cymosum capsules effectively alleviated symptoms such as colon length, weight loss, fecal viscosity, fecal blood and diarrhea in colitis rats. In addition, it up-regulated the protein expression of Occludin, Claudin-1, and Zona occludens-1 (ZO-1), thereby minimizing histological damage and restoring the colonic mucosal barrier. Fagopyrum cymosum capsules suppressed the levels of pro-inflammatory cytokines such as IL-6, IL-1 beta and IFN- gamma in colon tissue and also elevated the production of anti-inflammatory cytokine IL-4. The results of Illumina MiSequencing demonstrated that Fagopyrum cymosum capsules remodeled the gut microbiota dysbiosis in rats treated with DSS by increasing the level of alpha diversity of the intestinal microbiota, decreasing Firmicutes / Bacteroidetes ratio, and improving bacterial abundance, proliferating beneficial bacteria and inhibiting pathogenic organisms, which maintain mucosal immunity and intestinal barrier. In a word, our results suggest that Fagopyrum cymosum capsules had alleviating effects on DSS induced colitis, which could be associated with reshaping the gut microbiota and improving intestinal barrier function.