Zhang Huanxin, Xue Shizhen, Feng Yi, Shen Jun, Zhao Jixian
Department of Cardiology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China.
Exp Ther Med. 2020 Apr;19(4):2467-2474. doi: 10.3892/etm.2020.8517. Epub 2020 Feb 11.
Numerous reports have shown that dysfunction of vascular smooth muscle cells (VSMCs) serves a critical function in the development of cardiovascular disease, including coronary heart disease (CHD). microRNAs (miRNAs/miRs) have been reported to play important roles in regulating the function of VSMCs. The present study aimed to determine the role of miR-24-3p in VSMCs and to uncover the underlying mechanism. The expression of miR-24-3p in the peripheral blood samples of CHD patients was measured by reverse transcription-quantitative (RT-q)PCR. It was found that the level of miR-24-3p in the peripheral blood of patients with CHD was significantly upregulated compared with that in healthy controls. A dual luciferase reporter assay was performed to determine whether Bcl-2-like protein 11 (Bcl-2L11) was a target gene of miR-24-3p, and it was identified that Bcl-2L11 was a direct target of miR-24-3p. The mRNA level and protein expression of Bcl-2L11 in the peripheral blood of patients with CHD were measured by RT-qPCR and western blotting, respectively. The findings suggested that Bcl-2L11 was downregulated in the peripheral blood of patients with CHD. In addition, it was found that downregulation of miR-24-3p suppressed VSMC proliferation and promoted VSMC apoptosis, while the effects of the miR-24-3p inhibitor on cell viability and apoptosis were reversed by Bcl-2L11-small interfering (si)RNA. Additionally, downregulation of miR-24-3p increased the levels of Bcl-2L11, caspase-3 and Bax, and decreased Bcl-2 expression in VSMCs; these changes were abolished by Bcl-2L11-siRNA. In conclusion, the aforementioned results indicated that miR-24-3p was an important regulator in VSMC proliferation and apoptosis by targeting Bcl-2L11, which suggested that miR-24-3p might be a potential therapeutic target for the treatment of CHD.
大量报告表明,血管平滑肌细胞(VSMC)功能障碍在包括冠心病(CHD)在内的心血管疾病发展中起关键作用。据报道,微小RNA(miRNA/miR)在调节VSMC功能中发挥重要作用。本研究旨在确定miR-24-3p在VSMC中的作用,并揭示其潜在机制。通过逆转录定量(RT-q)PCR检测冠心病患者外周血样本中miR-24-3p的表达。结果发现,冠心病患者外周血中miR-24-3p水平较健康对照者显著上调。进行双荧光素酶报告基因检测以确定Bcl-2样蛋白11(Bcl-2L11)是否为miR-24-3p的靶基因,结果确定Bcl-2L11是miR-24-3p的直接靶标。分别通过RT-qPCR和蛋白质印迹法检测冠心病患者外周血中Bcl-2L11的mRNA水平和蛋白表达。结果表明,冠心病患者外周血中Bcl-2L11表达下调。此外,发现miR-24-3p的下调抑制VSMC增殖并促进VSMC凋亡,而Bcl-2L11小干扰(si)RNA可逆转miR-24-3p抑制剂对细胞活力和凋亡的影响。此外,miR-24-3p的下调增加了VSMC中Bcl-2L11、半胱天冬酶-3和Bax的水平,并降低了Bcl-2的表达;这些变化被Bcl-2L11-siRNA消除。总之,上述结果表明,miR-24-3p通过靶向Bcl-2L11是VSMC增殖和凋亡的重要调节因子,这表明miR-24-3p可能是治疗冠心病的潜在治疗靶点。