Abstract
It has been reported that miR-141-3p levels are markedly upregulated in the cardiomyocytes of obese rats induced by a high-fat diet. However, the role of miR-141-3p in myocardial lipotoxicity remains elusive. In the present study, the role of miR-141-3p in lipotoxic injury of H9c2 cells induced by palmitic acid (PA) and its possible mechanisms were assessed. The results indicated that miR-141-3p was significantly upregulated in PA-induced cardiomyocytes. miR-141-3p inhibitor enhanced the cell viability, reduced the release of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and troponin I (CTN-I), decreased cell apoptosis rate, and repressed the activation of mitochondrial apoptosis pathway in PA-treated H9c2, whereas treatment with miR-141-3p mimics resulted in the opposite effects. Mechanistically, it was further revealed that miR-141-3p could specifically bind to presenilin 1 (PSEN1) 3'UTR, and upregulating miR-141-3p levels reduced the expression of PSEN1, thereby inhibiting the activation of the Notch1/PTEN/AKT pathway. Additionally, inhibition of Notch1/AKT signaling pathway by its inhibitor could abrogate the effect of miR-141-3p on mitochondrial-mediated apoptosis induced by PA. In conclusion, the present study demonstrates that miR-141-3p regulates saturated fatty acid-induced cardiomyocyte apoptosis through Notch1/PTEN/AKT pathway via targeting PSEN1, which gains a new insight into the mechanisms of myocardial lipotoxic injury.