Ouabain alleviates Mycobacterium abscessus-triggered inflammatory responses through dual regulation of NLRP3 inflammasome activity and M1 macrophage polarization

Mycobacterium abscessus (M. abscessus), one of the most drug-resistant and difficult-to-treat pathogens, primarily causes chronic pulmonary inflammation in humans. The cardiac glycoside ouabain has demonstrated broad-spectrum anti-inflammatory properties in multiple disease models. However, its therapeutic potential against M. abscessus-induced pulmonary inflammation remains unexplored. In this study, we aim to investigate the role of ouabain on M. abscessus-induced inflammation. Our results demonstrated that ouabain remarkably attenuated M. abscessus-mediated inflammatory responses by decreasing the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β. H&E results showed that intraperitoneal administration of ouabain alleviated M. abscessus-induced pulmonary inflammation and injury. Transcriptomic analysis and qPCR results further revealed that ouabain treatment significantly suppressed the upregulation of pro-inflammatory cytokines induced by M.abscessus and downregulated NLRP3 inflammasome expression in vivo. In vitro experiments further confirmed that ouabain treatment effectively suppressed both NLRP3 inflammasome activation and M1 macrophage polarization. Collectively, these findings suggested that ouabain alleviated M. abscessus-induced pulmonary inflammation through dual mechanisms: inhibition of NLRP3 inflammasome activation and modulation of M1 macrophage polarization. This work highlights ouabain’s potential as a therapeutic candidate for combating M. abscessus infections.