Department of Critical Care Medicine, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, China.
Eur Rev Med Pharmacol Sci. 2021 Jan;25(1):335-343. doi: 10.26355/eurrev_202101_24399.
Acute myocardial infarction (AMI) is a serious cardiovascular disease that threatens human life. MicroRNA is considered to be an important participant in the pathophysiology of AMI. This article focused on the role of microRNA-495 (miR-495) in regulating apoptosis after myocardial infarction (MI) and its underlying mechanisms.
H9c2 cells were cultured in an incubator containing 1% O2 to establish a cell model of MI. Quantitative reverse-transcription polymerase chain reaction (RT-PCR) was utilized to detect miR-495 expression in H9c2 cells. The effects of miR-495 and NFIB on hypoxia-treated H9c2 cells were observed by Western blot, lactate dehydrogenase (LDH) detection, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, flow cytometry, and terminal dexynucleotidyl transferase(TdT)-mediated dUTP nick end labeling (TUNEL) staining. Luciferase reporter gene experiment was used to prove the regulatory relationship between miR-495 and NFIB.
Hypoxia induced injury to H9c2 cells, which was manifested by decreased cell viability, increased LDH release, increased pro-apoptotic proteins (Bax, Cleaved Caspase-3) expression, decreased anti-apoptotic protein (Bcl-2) expression, and increased in the rate of apoptosis and TUNEL positive cells. MiR-495 expression was remarkably increased in H9c2 cells treated with hypoxia. Inhibiting miR-495 expression markedly alleviated the hypoxia-induced injury in H9c2 cells, while silencing NFIB aggravated the hypoxia-induced damage. In addition, NFIB was confirmed to be the target of miR-495.
MiR-495 expression was increased in hypoxia-treated H9c2 cells. Silencing miR-495 could significantly inhibit hypoxia-induced apoptosis of H9c2 cells by targeting NFIB.
急性心肌梗死（AMI）是一种严重威胁人类生命的心血管疾病。miRNA 被认为是 AMI 病理生理学的重要参与者。本文重点研究了 microRNA-495（miR-495）在调节心肌梗死后细胞凋亡中的作用及其潜在机制。
在含有 1%氧气的培养箱中培养 H9c2 细胞，建立心肌梗死细胞模型。采用定量逆转录聚合酶链反应（RT-PCR）检测 H9c2 细胞中 miR-495 的表达。采用 Western blot、乳酸脱氢酶（LDH）检测、MTT（3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐）检测、流式细胞术和末端脱氧核苷酸转移酶（TdT）介导的 dUTP 缺口末端标记（TUNEL）染色观察 miR-495 和 NFIB 对缺氧处理的 H9c2 细胞的影响。采用荧光素酶报告基因实验证明 miR-495 和 NFIB 之间的调控关系。
缺氧诱导 H9c2 细胞损伤，表现为细胞活力降低、LDH 释放增加、促凋亡蛋白（Bax、Cleaved Caspase-3）表达增加、抗凋亡蛋白（Bcl-2）表达降低、细胞凋亡率和 TUNEL 阳性细胞增加。缺氧处理的 H9c2 细胞中 miR-495 表达明显增加。抑制 miR-495 表达显著减轻缺氧诱导的 H9c2 细胞损伤，而沉默 NFIB 则加重缺氧诱导的损伤。此外，NFIB 被证实是 miR-495 的靶标。
缺氧处理的 H9c2 细胞中 miR-495 表达增加。沉默 miR-495 可通过靶向 NFIB 显著抑制缺氧诱导的 H9c2 细胞凋亡。
