Department of Cardiology, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, 325000 Zhejiang, China.
Biomed Res Int. 2021 Mar 8;2021:8870674. doi: 10.1155/2021/8870674. eCollection 2021.
This study is aimed at investigating the therapeutic effects of tetrandrine (Tet) on myocardial ischemia reperfusion (I/R) injury and probe into underlying molecular mechanism.
H9C2 cells were divided into hypoxia/oxygenation (H/R) group, H/R+Tet group, H/R+Tet+negative control (NC) group, and H/R+Tet+miR-202-5p inhibitor group. RT-qPCR was utilized to monitor miR-202-5p and TRPV2 expression, and TRPV2 protein expression was detected via western blot and immunohistochemistry in H9C2 cells. Cardiomyocyte apoptosis was evaluated through detection of apoptosis-related markers and flow cytometry. Furthermore, myocardial enzyme levels were detected by ELISA. Rats were randomly separated into sham operation group, I/R group, I/R+Tet group (50 mg/kg), I/R+Tet+NC group, and I/R+Tet+miR-202-5p inhibitor group. miR-202-5p and TRPV2 mRNA expression was assessed by RT-qPCR. TRPV2 protein expression was detected through western blot and immunohistochemistry in myocardial tissues. Apoptotic levels were assessed via apoptosis-related proteins and TUNEL. Pathological changes were observed by H&E staining. Myocardial infarction size was examined by Evans blue-TCC staining.
Abnormally expressed miR-202-5p as well as TRPV2 was found in H/R H9C2 cells and myocardial tissues of I/R rats, which was ameliorated following Tet treatment. Tet treatment significantly suppressed H/R- or I/R-induced cardiomyocyte apoptosis. ELISA results showed that CK-MB and LDH levels were lowered by Tet treatment in H/R H9C2 cells and serum of I/R rats. H&E staining indicated that Tet reduced myocardial injury in I/R rats. Also, myocardial infarction size was lowered by Tet treatment. The treatment effects of Tet were altered following cotreatment with miR-202-5p inhibitor.
Our findings revealed that Tet may ameliorate myocardial I/R damage via targeting the miR-202-5p/TRPV2 axis.
本研究旨在探讨汉防己甲素（Tet）对心肌缺血再灌注（I/R）损伤的治疗作用，并探讨其潜在的分子机制。
将 H9C2 细胞分为缺氧/复氧（H/R）组、H/R+Tet 组、H/R+Tet+阴性对照（NC）组和 H/R+Tet+miR-202-5p 抑制剂组。利用 RT-qPCR 检测 miR-202-5p 和 TRPV2 的表达，并用 Western blot 和免疫组化检测 H9C2 细胞中 TRPV2 蛋白的表达。通过检测凋亡相关标志物和流式细胞术评估心肌细胞凋亡。此外，通过 ELISA 检测心肌酶水平。将大鼠随机分为假手术组、I/R 组、I/R+Tet 组（50mg/kg）、I/R+Tet+NC 组和 I/R+Tet+miR-202-5p 抑制剂组。通过 RT-qPCR 检测 miR-202-5p 和 TRPV2 mRNA 的表达。通过 Western blot 和免疫组化检测心肌组织中 TRPV2 蛋白的表达。通过凋亡相关蛋白和 TUNEL 评估凋亡水平。通过 H&E 染色观察病理变化。通过 Evans 蓝-TTC 染色检测心肌梗死面积。
在 H/R H9C2 细胞和 I/R 大鼠心肌组织中发现异常表达的 miR-202-5p 和 TRPV2，Tet 治疗后得到改善。Tet 治疗显著抑制 H/R 或 I/R 诱导的心肌细胞凋亡。ELISA 结果显示，Tet 治疗可降低 H/R H9C2 细胞和 I/R 大鼠血清中 CK-MB 和 LDH 水平。H&E 染色表明，Tet 减轻了 I/R 大鼠的心肌损伤。此外，Tet 治疗降低了心肌梗死面积。miR-202-5p 抑制剂共处理后，Tet 的治疗效果发生改变。
本研究结果表明，Tet 可能通过靶向 miR-202-5p/TRPV2 轴来改善心肌 I/R 损伤。
