Schisandrin B-mediated TH17 cell differentiation attenuates bowel inflammation.

Schisandrin B (Sch B) is the major active constituent of the traditional Chinese medicine Schisandra chinensis and has anti-inflammatory activity, but the target of Sch B remains unclear. T helper 17 (T17) cells have been involved in the pathogenesis of many autoimmune and inflammatory diseases. Here, we showed that Sch B could decrease IL-17A production of CD4 T cells by targeting STAT3 in vitro. Importantly, Sch B has therapeutic effects on DSS-induced acute and chronic colitis, CD4CD45RB T cell-induced colitis. Furthermore, we identified T17 cells as the direct target of Sch B for mediating its anti-inflammatory activity. Sch B could serve as a lead for developing new therapeutics against T17 cells or IL-17A cytokine-driven diseases.