Ergolide covalently binds NLRP3 and inhibits NLRP3 inflammasome-mediated pyroptosis

[Display omitted] •NLR family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis plays a key role in various acute and chronic inflammatory diseases. Targeted inhibition of NLRP3-mediated pyroptosis may be a potential therapeutic strategy for various inflammatory diseases.•Ergolide (ERG) is a sesquiterpene lactone natural product derived from the traditional Chinese medicinal herb, Inula britannica.•In our research, ERG was an efficient inhibitor of NLRP3-mediated pyroptosis in the first and second signals of NLRP3 inflammasome activation. ERG blocked NLRP3 inflammasome assembly. Drug affinity response target stability (DARTS) assays indicated that ERG irreversibly bound to the NLRP3 NACHT domain to prevent the assembly and activation of the NLRP3 inflammasome.•In animal experiments, ERG remarkably reduced mortality of wild-type septic mice and relieved lipopolysaccharide-induced acute lung injury of wild-type mice but not NLRP3 knockout mice.•ERG can serve as a precursor drug for the development of novel NLRP3 inhibitors to treat NLRP3 inflammasome mediated inflammatory diseases. NLR family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis plays a key role in various acute and chronic inflammatory diseases. Targeted inhibition of NLRP3-mediated pyroptosis may be a potential therapeutic strategy for various inflammatory diseases. Ergolide (ERG) is a sesquiterpene lactone natural product derived from the traditional Chinese medicinal herb, Inula britannica. ERG has been shown to have anti-inflammatory and anti-cancer activities, but the target is remains unknown. This study performed an in-depth investigation of the anti-inflammatory mechanism of ERG in NLRP3-mediated pyroptosis and NLPR3 inflammasome related sepsis and acute lung injury model. ELISA and Western blot were used to determine the IL-1β and P20 levels. Co-immunoprecipitation assays were used to detect the interaction between proteins. Drug affinity response target stability (DARTS) assays were used to explore the potential target of ERG. C57BL/6J mice were intraperitoneally injected with E. coli DH5α (2 × 109 CFU/mouse) to establish a sepsis model. Acute lung injury was induced by intratracheal administrationof lipopolysaccharide in wild-type mice and NLRP3 knockout mice with or without ERG treatment. We showed that ERG is an efficient inhibitor of NLRP3-mediated pyroptosis in the first and second signals of NLRP3 inflammasome activation. Furthermore, we demonstrated that ERG irreversibl