Cardioprotection of M2 macrophages-derived exosomal microRNA-24-3p/Tnfsf10 axis against myocardial injury after sepsis

OBJECTIVE: Some reports have suggested the involvement of microRNA-24-3p (miR-24-3p) in heart diseases. Here, the intention of this work was to unmask whether miR-24-3p from M2 macrophages-derived exosomes (M2-exo) could protect against myocardial injury after sepsis. METHODS: Mice model of sepsis was induced by intraperitoneal injection of lipopolysaccharide (LPS). miR-24-3p and tumor necrosis factor superfamily member 10 (Tnfsf10) expression levels were measured in the myocardial tissue of septic mice. M2-exo were isolated, in which miR-24-3p expression was altered. Then, septic mice were alone or in combination injected with the miR-24-3p-modified M2-exo or siRNA of Tnfsf10. Subsequently, cardiac function, apoptosis and serum inflammatory response were examined. RESULTS: miR-24-3p expression dropped while Tnfsf10 expression raised in the myocardial tissue of septic mice. M2-exo-derived miR-24-3p or deficiency of Tnfsf10 had cardioprotective effects on LPS-induced myocardial injury in mice through improving cardiac function and reducing cardiomyocyte apoptosis in the myocardial tissue and serum inflammation. A binding relation exhibited between miR-24-3p and Tnfsf10, and M2-exo-derived miR-24-3p alleviated LPS-induced myocardial injury by inhibiting Tnfsf10. CONCLUSION: Up-regulating miR-24-3p from M2-exo imposes cardioprotection against myocardial injury after sepsis through reducing Tnfsf10 expression.