Jiang Jin, Xu Jian, Tang Huifang
The First Affiliated Hospital of Nanhua University, Hengyang 421001, Hunan, China.
Protein Pept Lett. 2022;29(11):917-924. doi: 10.2174/0929866529666220819120736.
MicroRNA-490-3p (miR-490-3p) plays a role in the pathogeneses of a variety of cardiovascular diseases. Bioinformatic analysis showed that miR-490-3p was downregulated in the myocardial tissues of mice with myocardial infarction (MI). Nevertheless, the functions and mechanisms of miR-490-3p in MI remain unclear.
This study used an in-vitro model to investigate the role of miR-490-3p in MI. Human cardiac myocytes (HCMs) were cultured in a hypoxic environment. 3-(4,5)-Dimethylthiahiazo (-zy1)- 3,5-di-phenytetrazoliumromide (MTT) assay and flow cytometry were used to detect cell viability and apoptosis. The expression levels of forkhead box O1 (FOXO1) and miR-490-3p were detected by quantitative real-time PCR and Western blot. The levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), lactate dehydrogenase (LDH), cardiac troponin I (cTnI), and creatine kinase MB (CK-MB) were detected by enzyme-linked immunosorbent assay (ELISA). The targeted relationship between miR-490-3p and FOXO1 3'UTR was determined by a dual-luciferase reporter gene assay.
miR-490-3p was significantly down-regulated in hypoxia-induced HCM cells, while FOXO1 was markedly up-regulated. miR-490-3p overexpression inhibited HCM cell inflammatory responses and injury after hypoxia treatment. FOXO1 was validated to be a direct target of miR- 490-3p, and its overexpression weakened the effects of miR-490-3p on cell viability, apoptosis, as well as inflammatory responses.
miR-490-3p alleviates cardiomyocyte injury via targeting FOXO1 in MI.
微小RNA-490-3p（miR-490-3p）在多种心血管疾病的发病机制中发挥作用。生物信息学分析表明，在心肌梗死（MI）小鼠的心肌组织中miR-490-3p表达下调。然而，miR-490-3p在MI中的功能和机制仍不清楚。
本研究采用体外模型研究miR-490-3p在MI中的作用。将人心脏心肌细胞（HCMs）在缺氧环境中培养。采用3-（4,5）-二甲基噻唑-2,5-二苯基四氮唑溴盐（MTT）法和流式细胞术检测细胞活力和凋亡情况。通过定量实时PCR和蛋白质免疫印迹法检测叉头框O1（FOXO1）和miR-490-3p的表达水平。采用酶联免疫吸附测定（ELISA）法检测白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）、乳酸脱氢酶（LDH）、心肌肌钙蛋白I（cTnI）和肌酸激酶同工酶MB（CK-MB）的水平。通过双荧光素酶报告基因测定法确定miR-490-3p与FOXO1 3'非翻译区（UTR）之间的靶向关系。
在缺氧诱导的HCM细胞中，miR-490-3p显著下调，而FOXO1明显上调。miR-490-3p过表达抑制缺氧处理后HCM细胞的炎症反应和损伤。FOXO1被证实为miR-490-3p的直接靶点，其过表达减弱了miR-490-3p对细胞活力、凋亡以及炎症反应的影响。
在MI中，miR-490-3p通过靶向FOXO1减轻心肌细胞损伤。
