miR-181a 通过调节 akt 信号通路影响大鼠心肌缺血再灌注损伤。
MiR-181a affects myocardial ischemia-reperfusion injury in rats via regulating akt signaling pathway.
机构信息
Department of Gerontology, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
出版信息
Eur Rev Med Pharmacol Sci. 2019 Jul;23(14):6292-6298. doi: 10.26355/eurrev_201907_18451.
OBJECTIVE
The aim of this study was to explore the influence of the micro ribonucleic acid (miR)-181a on myocardial ischemia-reperfusion injury (MIRI) in rats by regulating the protein kinase B (Akt) signaling pathway.
MATERIALS AND METHODS
A total of 30 male Sprague-Dawley rats were randomly divided into three groups, including: sham operation group (Sham group), ischemia-reperfusion group (I/R group), and miR group (MiR-181a group). The model of myocardial ischemia-reperfusion was successfully established in rats. The concentration of blood nitric oxide (NO) was detected by the relative kits. Myocardial apoptosis in rats of the three groups was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Furthermore, the expressions of myocardial cell apoptosis-related proteins and tumor necrosis factor-α (TNF-α), and the degree of Akt phosphorylation were determined by Western blotting.
RESULTS
Compared with Sham group and miR-181a group, I/R group exhibited significantly elevated left ventricular end-diastolic pressure (LVEDP) (p<0.05). However, the left ventricular end-systolic pressure (LVESP), stroke work (SW), differential pressure (DP), end-systolic pressure-volume relationship (ESPVR), and end-diastolic pressure-volume relationship (EDPVR) significantly decreased in the I/R group (p<0.05). In comparison with miR-181a group, the apoptosis index of myocardial cells was remarkably elevated in the I/R group, showing statistically significant differences (p<0.05). The protein bands were analyzed using the Quantity One detection software. The results demonstrated that, compared with the Sham group, I/R group showed significantly elevated expressions of cysteine-aspartic protease (Caspase)-3 and TNF-α in rat myocardial tissues (p<0.05). However, the protein levels of Akt and endothelial NO synthase (eNOS) phosphorylation and NO in rat myocardial cells were significantly down-regulated (p<0.05).
CONCLUSIONS
MiR-181a activates Akt to promote the phosphorylation of its downstream protein eNOS, inhibit the apoptosis of myocardial cells, and alleviate MIRI.
目的
本研究旨在探讨微小 RNA-181a（miR-181a）通过调控蛋白激酶 B（Akt）信号通路对大鼠心肌缺血再灌注损伤（MIRI）的影响。
材料与方法
将 30 只雄性 Sprague-Dawley 大鼠随机分为三组，分别为假手术组（Sham 组）、缺血再灌注组（I/R 组）和 miR-181a 组（MiR-181a 组）。成功建立大鼠心肌缺血再灌注模型。采用相对试剂盒检测各组大鼠血液中一氧化氮（NO）的浓度。采用末端脱氧核苷酸转移酶介导的 dUTP 缺口末端标记法（TUNEL）检测各组大鼠心肌细胞凋亡情况。采用 Western blot 法检测各组大鼠心肌细胞凋亡相关蛋白及肿瘤坏死因子-α（TNF-α）的表达，以及 Akt 磷酸化程度。
结果
与 Sham 组和 miR-181a 组相比，I/R 组大鼠左心室舒张末期压（LVEDP）明显升高（p<0.05），左心室收缩末期压（LVESP）、每搏功（SW）、压差（DP）、收缩末期压力-容积关系（ESPVR）和舒张末期压力-容积关系（EDPVR）明显降低（p<0.05）。与 miR-181a 组相比，I/R 组大鼠心肌细胞凋亡指数明显升高，差异有统计学意义（p<0.05）。采用 Quantity One 检测软件对蛋白条带进行分析。结果表明，与 Sham 组相比，I/R 组大鼠心肌组织中半胱氨酸天冬氨酸蛋白酶（Caspase）-3 和 TNF-α表达明显升高（p<0.05），而大鼠心肌细胞中 Akt 和内皮型一氧化氮合酶（eNOS）磷酸化及 NO 蛋白水平明显下调（p<0.05）。
结论
miR-181a 通过激活 Akt 促进其下游蛋白 eNOS 磷酸化，抑制心肌细胞凋亡，从而减轻 MIRI。
Zotero 插件