Liu Ye, Song Bing, Zheng Wei, Hu Jing
Electrocardial Center, Jinzhou Medical University, Jinzhou 121000, China.
Department of Endocrine and Metabolic Diseases, First Affiliated Hospital, Jinzhou Medical University, Jinzhou 121000, China. *Corresponding author, E-mail:
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2020 Oct;36(10):877-883.
Objective To investigate the expression levels of microRNA-186-5p (miR-186-5p) and Toll-like receptor 3 (TLR3) and their relationships with the apoptosis in high-glucose (HG)-treated AC16 cardiomyocytes. Methods Target Scan7.1 database predicted that miR-186-5p could act directly on TLR3. Diabetic cardiomyopathy model was established in cardiomyocytes stimulated by HG. The expression of miR-186-5p was detected by real-time quantitative PCR and the expression of TLR3 was detected by Western blot analysis. The expression of miR-186-5p or TLR3 was enhanced or reduced by cell transfection. The apoptosis of cardiomyocytes was detected by flow cytometry. The expression of cleaved caspase-3(c-caspase-3) was detected by Western blot analysis, and the interaction between miR-186-5p and TLR3 was analyzed by luciferase activity assay. Results The bioinformatics analysis and luciferase activity assay showed that TLR3 was a direct target gene of miR-186-5p. The expression of miR-186-5p was down-regulated in HG-treated cardiomyocytes, and the over-expression of miR-186-5p reversed HG-induced cardiomyocyte apoptosis and reduced the protein level of c-caspase-3. Down-regulation of TLR3 inhibited HG-induced apoptosis and reduced protein level of c-caspase-3 in cardiomyocytes. Over-expression of TLR3 increased HG-induced cardiomyocyte apoptosis and reversed the effect of miR-186-5p. Conclusion The miR-186-5p can inhibit the apoptosis of cardiomyocytes induced by HG via down-regulating TLR3 expression.
目的 探讨微小RNA-186-5p（miR-186-5p）和Toll样受体3（TLR3）的表达水平及其与高糖（HG）处理的AC16心肌细胞凋亡的关系。方法 Target Scan7.1数据库预测miR-186-5p可直接作用于TLR3。在HG刺激的心肌细胞中建立糖尿病心肌病模型。采用实时定量PCR检测miR-186-5p的表达，采用蛋白质免疫印迹法检测TLR3的表达。通过细胞转染增强或降低miR-186-5p或TLR3的表达。采用流式细胞术检测心肌细胞凋亡。采用蛋白质免疫印迹法检测裂解的半胱天冬酶-3（c-caspase-3）的表达，并通过荧光素酶活性测定分析miR-186-5p与TLR3之间的相互作用。结果 生物信息学分析和荧光素酶活性测定表明，TLR3是miR-186-5p的直接靶基因。HG处理的心肌细胞中miR-186-5p的表达下调，miR-186-5p的过表达逆转了HG诱导的心肌细胞凋亡，并降低了c-caspase-3的蛋白水平。TLR3的下调抑制了HG诱导的凋亡，并降低了心肌细胞中c-caspase-3的蛋白水平。TLR3的过表达增加了HG诱导的心肌细胞凋亡，并逆转了miR-186-5p的作用。结论 miR-186-5p可通过下调TLR3表达抑制HG诱导的心肌细胞凋亡。
