SS-31 protects against paraquat-induced lung injury and fibrosis via inhibition of the MAPK signal pathway

Aims: To explore the therapeutic effect of SS-31 on lung injury and lung fibrosis caused by paraquat (PQ). Methods: In vivo experiments involved the intraperitoneal injection of PQ solution into C57BL/6 mice to induce lung injury and fibrosis. Subsequently, SS-31 solution was administered intraperitoneally on a daily basis to investigate its protective effects against PQ-induced lung injury and fibrosis. In vitro use of PQ caused inflammatory responses in A549 cell line, and the therapeutic effects of SS-31 were explored by treatment with different concentrations of SS-31 in A549. The SS-31 pathway of action was explored and validated by RNA sequencing. Results: In vivo, SS-31 reduced PQ-induced mortality, acute lung injury, lung fibrosis and apoptosis in mice. The same results were obtained iin vitro experiments. SS-31 was found to inhibit the MAPK pathway by RNA sequencing. The mechanism was further validated by verifying MAPK pathway proteins and applying MAPK pathway agonists. Innovation and Conclusion: In vivo and in vitro experiments demonstrated that SS-31 reduces lung injury and fibrosis induced by PQ. It works through inhibition of the MAPK signaling pathway.