Nicorandil alleviates myocardial injury and post-infarction cardiac remodeling by inhibiting Mst1.

Abstract Background Cardiomyocyte autophagy and apoptosis are crucial events underlying the development of cardiac abnormalities and dysfunction after myocardial infarction (MI). A better understanding of the cell signaling pathways involved in cardiac remodeling may support the development of new therapeutic strategies for the treatment of heart failure (HF) after MI. Methods A cardiac MI injury model was constructed by ligating the left anterior descending (LAD) coronary artery. Neonatal cardiomyocytes were isolated and cultured to investigate the mechanisms underlying the protective effects of nicorandil on MI-induced injury. Results Nicorandil reduced cardiac enzyme release, mitigated left ventricular enlargement and cardiac dysfunction after MI, as evaluated by echocardiography and hemodynamic measurements. According to the results of the western blot analysis and immunofluorescence staining, nicorandil enhanced autophagic flux and reduced apoptosis in cardiomyocytes subjected to hypoxic injury. Interestingly, nicorandil increased Mst1 and p-Mst1 levels in cardiomyocytes subjected to MI injury. Mst1 knockout abolished the protective effects of nicorandil on cardiac remodeling and dysfunction after MI. Mst1 knockout also abolished the beneficial effects of nicorandil on cardiac enzyme release and cardiomyocyte autophagy and apoptosis. Conclusions Nicorandil alleviates post-MI cardiac dysfunction and remodeling. The mechanisms were associated with enhancing autophagy and inhibiting apoptosis through Mst1 inhibition.