Department of Cardiology, The First Affiliated Hospital of China Medical University, Liaoning, China.
The Central Laboratory, The First Affiliated Hospital of China Medical University, Liaoning, China.
Environ Toxicol. 2022 Apr;37(4):741-753. doi: 10.1002/tox.23439. Epub 2021 Dec 12.
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.
据报道,高脂肪饮食诱导肥胖大鼠的心肌细胞中 miR-141-3p 水平明显上调。然而,miR-141-3p 在心肌脂肪毒性中的作用仍不清楚。本研究评估了 miR-141-3p 在软脂酸(PA)诱导的 H9c2 细胞脂肪毒性损伤中的作用及其可能的机制。结果表明,PA 诱导的心肌细胞中 miR-141-3p 明显上调。miR-141-3p 抑制剂增强细胞活力,降低乳酸脱氢酶(LDH)、肌酸激酶同工酶-MB(CK-MB)和肌钙蛋白 I(CTN-I)的释放,降低细胞凋亡率,并抑制 PA 处理的 H9c2 中线粒体凋亡途径的激活,而 miR-141-3p 模拟物的处理则产生相反的效果。机制上,进一步揭示 miR-141-3p 可以特异性结合早老素 1(PSEN1)3'UTR,上调 miR-141-3p 水平降低 PSEN1 的表达,从而抑制 Notch1/PTEN/AKT 通路的激活。此外,其抑制剂抑制 Notch1/AKT 信号通路可以消除 miR-141-3p 对 PA 诱导的线粒体介导凋亡的作用。综上所述,本研究表明,miR-141-3p 通过靶向 PSEN1 调节饱和脂肪酸诱导的心肌细胞凋亡,通过 Notch1/PTEN/AKT 通路,为心肌脂肪毒性损伤的机制提供了新的见解。