Protective effects of wedelolactone on dextran sodium sulfate induced murine colitis partly through inhibiting the NLRP3 inflammasome activation via AMPK signaling.

It has been reported that the ethanol extract of Wedelia chinensis attenuates murine colitis. Wedelolactone (WEL), a coumestane-type compound with many pharmacological activities, was isolated from W. chinensis. The present study aims to investigate the beneficial effects and underlying mechanisms of WEL on ulcerative colitis. In a dextran sodium sulfate (DSS)-induced mouse model, oral administration of WEL (50mg/kg) significantly attenuated pathological colonic damage and inhibited inflammatory infiltration, myeloperoxidase and alkaline phosphatase activities through MAPKs and NF-κB signaling pathways, while activating AMPK in colons treated with DSS. Further study revealed that WEL treatment dramatically inhibited NLRP3 inflammasome activation and caspase-1 phosphorylation to decrease IL-1β release in colons treated with DSS. In addition, WEL effectively regulates the disorder of skeleton proteins in colonic epithelial cells NCM460 exposed to TNF-α and protects the intestinal barrier function by activating AMPK in vivo. In summary, the AMPK-NLRP3-IL-1β signaling axis plays an important role in colitis following WEL treatments. These findings provide new insights into the pharmacological actions of WEL as a potential therapeutic agent for colitis.