Department of Emergency Medicine, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China.
Eur Rev Med Pharmacol Sci. 2020 Mar;24(5):2659-2666. doi: 10.26355/eurrev_202003_20535.
To study the influence of micro ribonucleic acid (miR)-26a on myocardial cell apoptosis in rats with acute myocardial infarction (AMI) through the glycogen synthase kinase 3 beta (GSK-3β) pathway.
A total of 36 Sprague-Dawley rats were randomly divided into sham group (n=12), model group (n=12), and miR-26a mimics group (n=12). Only the heart was exposed, and normal saline was intraperitoneally injected postoperatively in sham group, and the model of AMI was prepared in model group. Besides, after modeling, miR-26a mimics were injected into the left ventricle in miR-26a mimics group. At 48 h after operation, sampling was performed. Then, the expressions of B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X protein (Bax), as well as the protein expression of phosphorylated GSK-3β (p-GSK-3β) were detected via immunohistochemistry and Western blotting, respectively. Moreover, the expression level of miR-26a was measured via quantitative polymerase chain reaction (qPCR), and cell apoptosis was evaluated using terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay.
Compared with those in sham group, the expression level of Bax was substantially raised, but that of Bcl-2 was notably lowered in model group and miR-26 mimics group (p<0.05), and miR-26 mimics group had a markedly lower expression level of Bax and a remarkably higher expression level of Bcl-2 than model group (p<0.05). According to Western blotting results, the protein expression level of p-GSK-3β in model and miR-26a mimics groups was considerably higher than that in sham group (p<0.05), and miR-26a mimics group exhibited a notably higher protein expression level of p-GSK-3β than model group (p<0.05). In comparison with that in sham group, the expression level of miR-26a rose markedly in both model group and miR-26a mimics group (p<0.05), and its expression level in miR-26a mimics group was dramatically higher than that in model group (p<0.05). Additionally, the TUNEL-positive cells were considerably increased in both model group and miR-26a mimics group in comparison with that in sham group (p<0.05), and miR-26a mimics group had markedly fewer TUNEL-positive cells than model group (p<0.05).
MiR-26a activates the GSK-3β signaling pathway to inhibit myocardial cell apoptosis after AMI.
通过糖原合酶激酶 3β（GSK-3β）通路研究微小 RNA-26a 对急性心肌梗死（AMI）大鼠心肌细胞凋亡的影响。
36 只 Sprague-Dawley 大鼠随机分为假手术组（n=12）、模型组（n=12）和 miR-26a 模拟物组（n=12）。假手术组仅暴露心脏，术后腹腔内注射生理盐水，模型组制备 AMI 模型。此外，miR-26a 模拟物组在造模后将 miR-26a 模拟物注入左心室。术后 48 h 取样。然后，通过免疫组织化学和 Western blot 分别检测 B 细胞淋巴瘤 2（Bcl-2）和 Bcl-2 相关 X 蛋白（Bax）的表达以及磷酸化 GSK-3β（p-GSK-3β）的蛋白表达。此外，通过实时定量聚合酶链反应（qPCR）测量 miR-26a 的表达水平，并通过末端脱氧核苷酸转移酶（TdT）dUTP 缺口末端标记（TUNEL）测定细胞凋亡。
与假手术组相比，模型组和 miR-26a 模拟物组 Bax 的表达水平显著升高，而 Bcl-2 的表达水平显著降低（p<0.05），miR-26a 模拟物组 Bax 的表达水平显著低于模型组，Bcl-2 的表达水平显著高于模型组（p<0.05）。根据 Western blot 结果，模型组和 miR-26a 模拟物组 p-GSK-3β 的蛋白表达水平明显高于假手术组（p<0.05），而 miR-26a 模拟物组的 p-GSK-3β 蛋白表达水平明显高于模型组（p<0.05）。与假手术组相比，模型组和 miR-26a 模拟物组 miR-26a 的表达水平明显升高（p<0.05），miR-26a 模拟物组的表达水平明显高于模型组（p<0.05）。此外，与假手术组相比，模型组和 miR-26a 模拟物组的 TUNEL 阳性细胞明显增多（p<0.05），miR-26a 模拟物组的 TUNEL 阳性细胞明显少于模型组（p<0.05）。
miR-26a 通过激活 GSK-3β 信号通路抑制 AMI 后心肌细胞凋亡。
