IL-10-dependent Effect of Chinese Medicine Abelmoschus manihot on Alleviating Intestinal Inflammation and Modulating Gut Microbiota

Inflammatory bowel disease (IBD) is a recurrent disease associated with a potential risk of colorectal cancer. Abelmoschus manihot (AM), a Chinese herbal medicine, is known to alleviate IBD. However, its mechanism of action requires further clarification. Here, we focused on the role of IL-10 and the gut microbiota in the mechanism of action of AM. The effects of AM on intestinal inflammation, mucus production, and gut microbes were evaluated in dextran sodium sulfate (DSS)-induced acute and chronic IBD models and in IL-10-deficient mice (IL-10 − ∕ − ). AM exhibited protective effects on acute and chronic models of IBD in wild-type mice by restoring body weight and colon length, promoting IL-10 secretion, and decreasing TNF- α levels. Moreover, AM alleviated inflammatory infiltration, increased mucin 2 transcription, and increased the number of goblet cells in the colon. On the contrary, these effects were diminished in IL-10 − ∕ − mice, which implied that the effect of AM on intestinal inflammation is IL-10-dependent. A gut microbial sequencing analysis showed that gut microbial dysbiosis was modulated by AM intervention. The regulatory effects of AM on Eggerthellaceae , Sutterellaceae , Erysipelotrichaceae , Burkholderiaceae , Desulfovibrionaceae , and Enterococcaceae were dependent on IL-10. These results revealed that AM ameliorated IBD and modulated gut microbes by promoting IL-10 secretion, indicating that AM has the potential to improve IBD and that AM is IL-10-dependent.