Sulforaphane ameliorates DSS-induced colitis and secondary liver injury in mice: Proposed mechanism in the SCFAs-FFAR2/3-macrophage polarization axis.

Sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables, has shown therapeutic potential in inflammatory diseases. Our previous studies demonstrated that SFN ameliorates ulcerative colitis (UC) and restores gut microbiota composition in dextran sulfate sodium (DSS)-induced mice. In the present study, we further investigate the protective effects and underlying mechanisms of SFN against secondary liver injury associated with UC. The results revealed that SFN significantly alleviated pathological damage in both the colon and liver, improved liver function parameters, upregulated intestinal tight junction proteins and Muc2 expression, and inhibited inflammation in DSS-induced colitis mice. Additionally, SFN significantly elevated short-chain fatty acid (SCFA) concentrations, enhanced the expression of SCFA receptors (free fatty acid receptors 2 and 3, FFAR2/3), and modulated macrophage polarization by inhibiting M1 and promoting M2 phenotypes in the colon and liver. Collectively, these findings suggest that SFN may alleviate colitis and secondary liver injury by enhancing intestinal barrier function and reducing inflammatory responses, potentially via the SCFAs-FFAR2/3-macrophage polarization signaling cascade. Thus, SFN may serve as a promising adjunctive therapeutic agent for the prevention and treatment of UC.