Abstract: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.