Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Middle Yanchang Road, Shanghai 200072, China.
Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Middle Yanchang Road, Shanghai 200072, China.
Toxicol In Vitro. 2021 Jun;73:105131. doi: 10.1016/j.tiv.2021.105131. Epub 2021 Feb 27.
The pathogenesis of acute myocardial infarction (AMI) is associated with cardiomyocyte necrosis and apoptosis. Numerous studies have determined the regulatory effects of Phosphatase and tensin homolog (PTEN) cell proliferation and apoptosis in other cell types. However, the potential role of PTEN in cardiomyocyte is unclear. In this study, we used H9c2 cells cultured under serum deprivation to simulate the apoptosis process of myocardial infarction. Small interference RNA (siRNA) of PTEN was used to knock down the expression of PTEN. Cell viability was determined by CCK-8. Cell proliferation was examined by Edu staining, and the protein expression was analyzed by Western blot. We also evaluated the generation of ROS, the degree of DNA damage, and cell apoptosis using immunofluorescence assay. As a result, we observed that serum deprivation in H9c2 cells increased PTEN expression. Functionally, the PTEN knockdown experiment using siRNA inhibited serum deprivation-induced cell apoptosis, ROS production, and DNA damage, whereas increased cell proliferation. All these effects could be reversed by phosphatidylinositol 3-kinase (PI3K) inhibitor, which indicated the PI3K/protein kinase B (AKT) might be the critical component of the PTEN effects during serum deficiency. In conclusion, our study indicated the role of the PTEN/PI3K/AKT pathway in serum deprivation-induced cytotoxicity in H9c2 cells.
急性心肌梗死（AMI）的发病机制与心肌细胞坏死和凋亡有关。大量研究已经确定了磷酸酶和张力蛋白同源物（PTEN）在其他细胞类型中对细胞增殖和凋亡的调节作用。然而，PTEN 在心肌细胞中的潜在作用尚不清楚。在这项研究中，我们使用血清剥夺培养的 H9c2 细胞来模拟心肌梗死的细胞凋亡过程。使用小干扰 RNA（siRNA）敲低 PTEN 的表达。通过 CCK-8 测定细胞活力。通过 Edu 染色检测细胞增殖，通过 Western blot 分析蛋白表达。我们还通过免疫荧光法评估 ROS 的产生、DNA 损伤程度和细胞凋亡。结果表明，血清剥夺可增加 H9c2 细胞中的 PTEN 表达。功能上，使用 siRNA 的 PTEN 敲低实验抑制了血清剥夺诱导的细胞凋亡、ROS 产生和 DNA 损伤，同时增加了细胞增殖。PI3K 抑制剂可逆转所有这些作用，表明在血清缺乏时，PTEN 效应的关键组成部分可能是 PI3K/蛋白激酶 B（AKT）。总之，我们的研究表明 PTEN/PI3K/AKT 通路在血清剥夺诱导的 H9c2 细胞细胞毒性中的作用。
