Dihydromyricetin a potential candidate for the treatment of cholestatic liver injury via inhibition of the NLRP3 inflammasome

Abstract

Objective Cholestatic liver injury is a hepatic disorder caused by abnormal bile acid metabolism and biliary obstruction, with limited clinical treatment options. Activation of the NLRP3 inflammasome is recognized as a key pathogenic mechanism. This study aims to investigate whether DHM, a natural flavonoid, alleviates cholestatic liver injury by modulating the NLRP3 inflammasome and to elucidate its underlying mechanism. Methods The protective effects of DHM were evaluated both in vivo (using an ANIT-induced mouse cholestasis model) and in vitro (using an LPS plus nigericin-induced ANA-1 macrophage model). Assessments included liver function, histopathology, inflammatory cytokine levels, and the expression of key molecules in the NLRP3 inflammasome pathway (NLRP3, ASC, Caspase-1, GSDMD, IL-1β, IL-18). Cell viability was measured by CCK-8 assay, while molecular expression was analyzed via Western blot, qPCR, ELISA, and immunofluorescence. The specific role of NLRP3 was confirmed using siRNA knockdown. Results DHM demonstrated good safety profiles in both experimental settings. In the ANIT-induced cholestatic model, DHM significantly improved liver function markers (ALT, AST, ALP, TBIL), reduced histopathological damage, and suppressed the expression and activation of key components in the NLRP3 inflammasome pathway. In vitro studies further confirmed that DHM exerts its anti-inflammatory effects by inhibiting ROS burst, preventing NLRP3 inflammasome assembly, and blocking the subsequent pyroptosis process. NLRP3 knockdown experiments indicated that the anti-inflammatory effect of DHM is highly dependent on the presence of NLRP3. Conclusion DHM alleviates cholestatic liver injury by inhibiting the activation of the NLRP3 inflammasome in macrophages, a mechanism involving multi-level anti-inflammatory and antioxidant pathways. This study provides a theoretical foundation for DHM as a potential therapeutic agent against cholestatic liver injury and identifies the NLRP3 inflammasome as its critical molecular target.