MicroRNA-126 在动脉粥样硬化性脑梗死患者 血清中的表达变化及其机制研究

目的 观察microRNA（miR-126）在动脉粥样硬化性脑梗死（ACI）患者血清中的表达变化及 其对血管平滑肌细胞增殖和迁移的影响，并探讨其机制。方法 选取2015 年11 月—2017 年11 月莱芜市人 民医院发病7 d 内就诊的150 例急性脑梗死患者，分为ACI 组110 例（稳定斑块患者74 例，不稳定斑块患 者36 例）和非动脉粥样硬化性脑梗死（NACI）患者40 例，同时选择同期40 例年龄、性别相匹配的健康志 愿者作为对照组。实时荧光定量聚合酶链反应（qRT-PCR）检测3 组血清miR-126 的表达，体外培养人血 管平滑肌细胞系HA-VSMC，分别转染miR-126 模拟物、模拟物阴性对照和miR-126 抑制物、抑制物阴性 对照。采用qRT-PCR 检测miR-126 的表达；CCK-8 法检测细胞增殖活性；Transwell 迁移实验检测细胞 迁移能力；Western blotting 检测基质金属蛋白酶13（MMP-13）蛋白的表达。结果 ACI 组患者血清miR- 126 表达水平较NACI 组和对照组降低（P <0.05），且不稳定斑块患者血清miR-126 表达水平低于稳定斑块 患者（P <0.05）。与模拟物阴性对照组比较，miR-126 模拟物组细胞miR-126 表达水平升高（P <0.05），细 胞增殖活性和迁移能力下降（P <0.05），MMP-13 表达升高（P <0.05）；与抑制物阴性对照组比较，miR- 126 抑制物组细胞增殖活性和迁移能力提高（P <0.05），MMP-13 表达降低（P <0.05）。结论 ACI 患者血清 miR-126 表达降低，并可通过抑制血管平滑肌细胞的增殖和迁移起到抗动脉粥样硬化作用，其机制可能与下 调MMP-13 的表达有关。

Changes of serum miR-126 expression in patients with atherosclerosis cerebral infarction and its mechanism

Objective To observe the expression of miR-126 in serum in patients with atherosclerosis cerebral infarction (ACI) and its influence on the proliferation and migration of vascular smooth muscle cells, and to probe the potential mechanism. Methods Totally 150 acute cerebral infarction patients consulted in the Department of Neurology in our hospital were selected and divided into ACI group (n = 110, including 74 patients with stable plaque and 36 patients with unstable plaque) and the non-atherosclerosis cerebral infarction (NACI) group (n = 40). Meanwhile, additional 40 healthy volunteers with matched sex and age were enrolled at the same period into the control group. The serum miR-126 expression levels in each group were detected using quantitative real-time fluorescence PCR (qRT-PCR). Besides, human vascular smooth muscle cell line HA-VSMC was cultured in vitro, and transfected with miR-126 mimics, mimics negative control, miR-126 inhibitor and inhibitor negative control, respectively. The miR-126 expression was detected by qRT-PCR; the cell proliferation activity was examined through CCK-8 assay; cell migration capacity was detected through Transwell assay; and MMP-13 protein expression was detected by Western blotting. Results Serum miR-126 expression level in ACI group was lower than that in NACI group and control group (P < 0.05), and that in patients with unstable plaque was lower than that in those with stable plaque (P < 0.05). Compared with the cells in the mimics negative control group, the miR-126 expression level in miR-126 mimics group was up-regulated (P < 0.05), while cell proliferation activity and migration capacity were distinctly reduced (P < 0.05), and MMP-13 expression level was evidently increased (P < 0.05). Compared with the cells in inhibitor negative control group, the cell proliferation activity and migration capacity in miR-126 inhibitor group were notably elevated (P < 0.05), while MMP-13 expression level was distinctly reduced (P < 0.05). Conclusions The expression of miR-126 in serum of patients with ACI decreased, and miR-126 can suppress the proliferation and migration of vascular smooth muscle cells to resist atherosclerosis, the mechanism of which may be related to the down-regulation of MMP-13 expression.