miR-146a对高糖诱导的人视网膜微血管内皮细胞增殖和新生血管生成的影响及其机制

目的　探讨miR-146a对高糖诱导的人视网膜微血管内皮细胞（HRMEC）增殖和新生血管生成的影响及其机制。方法　选取对数生长期的HRMEC，将细胞分为正常组、高渗组、高糖组、阴性对照组、miR-146a mimics组、miR-146a mimics+IL-17A组。正常组细胞用含5.5 mmol·L^-1 D-葡萄糖的培养基培养24 h，高渗组细胞用含5.5 mmol·L^-1 D-葡萄糖和50 mmol·L^-1甘露醇的培养基培养24 h；其余各组细胞先用含30 mmol·L^-1 D-葡萄糖的培养基培养24 h后,阴性对照组、miR-146a mimics组、miR-146a mimics+IL-17A组分别转染阴性对照序列+pcDNA3.1空质粒、miR-146a mimics质粒、miR-146a mimics+pcDNA3.1-IL-17A质粒。采用MTT法检测细胞活力,细胞划痕实验检测细胞迁移活性,Matrigel法检测细胞管腔形成情况,Western blot法检测相关蛋白表达。结果　与正常组相比，高糖组细胞活力、细胞迁移率和细胞环状结构数量均升高，VEGF、VEGF受体2、白细胞介素-17A、磷酸化磷脂酰肌醇3-激酶（p-PI3K)、磷酸化蛋白激酶B（p-AKT)蛋白表达亦均升高（均为P<0.05）；而miR-146a mimics组上述指标则较高糖组均降低（均为P<0.05）；miR-146a mimics+IL-17A组上述指标均高于miR-146a mimics组（均为P<0.05）。结论　上调miR-146a表达可有效地降低高糖诱导的HRMEC增殖和新生血管生成，其作用机制可能与降低IL-17A表达进而抑制PI3K/AKT通路激活有关。

Effect and mechanism of miR-146a on proliferation and angiogenesis of high glucose-induced human retinal microvascular endothelial cells

Objective To investigate the effect and mechanism of miR-146a on proliferation and angiogenesis of high glucose-induced human retinal microvascular endothelial cells(HRMEC).Methods HRMEC in the logarithmic growth phase were divided into the normal group,hypertonic group,high-glucose group,negative control group,miR-146a mimics group,and miR-146a mimics+interleukin-17A(IL^-17A)group.Cells in the normal group were cultured for 24 hours in a medium containing 5.5 mmol·L^-1 D-glucose,cells in the hypertonic group were cultured for 24 hours in a medium containing 5.5 mmol·L^-1 D-glucose and 50 mmol·L^-1 mannitol,while cells in the other groups were cultured for 24 hours in a medium containing 30 mmol·L^-1 D-glucose.Besides,cells in the negative control group,miR-146a mimics group,and miR-146a mimics+IL^-17A group were transfected with negative control sequence+pcDNA3.1 empty plasmid,miR-146a mimics plasmid,miR-146a mimics+pcDNA3.1-IL^-17A plasmid,respectively.MTT assay was used to detect the cell viability,the wound healing assay was used to detect the cell migration,and the Matrigel assay was used to detect the tube formation.The protein expression was determined by the Western blot.Results Compared with the normal group,the cell viability,cell migration rate,and the number of ring structures in the high-glucose group were all increased,so were the protein expression levels of vascular endothelial growth factor(VEGF),VEGF receptor 2,IL^-17A,phosphorylated phosphatidylinositide 3-kinase(PI3K),and phosphorylated protein kinase B(AKT)(all P<0.05).Said indicators in the miR-146a mimics group were decreased compared with the high-glucose group(all P<0.05),while said indicators in the miR-146a mimics+IL^-17A group were increased compared with the miR-146a mimics group(all P<0.05).Conclusion Up-regulation of miR-146a expression can effectively reduce the proliferation and angiogenesis of HRMEC induced by high glucose,which may be associated with the inhibited activation of the PI3K/AKT pathway due to a decrease in IL^-17A expression.