miR-29a抑制KLF4对血管平滑肌细胞表型转化的影响  

Effects of inhibition of KLF4 expression by miR-29a on transformation of phenotype of vascular smooth muscle cells

作　　者：钱德慧[1] 晋军[1] 秦浙学[1] 刘曦[1] 黄岚[1] 

机构地区：[1]第三军医大学新桥医院全军心血管病研究所,重庆400038

出　　处：《解放军医学杂志》2014年第10期787-790,共4页Medical Journal of Chinese People's Liberation Army

基　　金：2012年重庆市科委重点实验室开放课题资助项目(2012C267)~~

摘　　要：目的探讨miR-29a是否可通过抑制KLF4表达影响血管平滑肌细胞(VSMCs)的表型转化。方法原代培养大鼠VSMCs。采用荧光素酶报告基因系统验证KLF4是否为miR-29a靶基因。将VSMCs分为转染miR-29a表达质粒组、转染阴性表达质粒组及未转染质粒组,采用Western blotting检测KLF4及VSMCs收缩表型蛋白的表达,[3H]-TdR掺入法检测VSMCs的增殖能力。结果共转染野生型KLF4荧光素报告基因+miR-29a表达质粒的实验组中,荧光素酶活性显著降低。转染miR-29a表达质粒组KLF4蛋白表达水平(0.36±0.02)显著低于未转染组(1.52±0.06)及转染阴性表达质粒组(1.55±0.05,P<0.01)。与未转染及转染阴性表达质粒组相比,转染miR-29a表达质粒组VSMCs收缩表型相关蛋白SMMHC、SM-22α、calponin的表达均明显增高,增殖能力明显降低。结论 miR-29a可靶向抑制KLF4表达,进而维持VSMCs的收缩表型,降低其增殖能力。Objective To explore whether miR-29 a can influence the phenotypic transformation of vascular smooth muscle cells（VSMCs） by inhibiting expression of Kruppel-like factor 4（KLF4）. Methods Rat VSMCs were cultured primarily. The luciferase reporter system was used to verify whether KLF4 is the target gene of miR-29 a. VSMCs were divided into miR-29 atransfected expression plasmid group, transfection-negative expression plasmid group, and no-transfection group. The expression of KLF4 and VSMC contractile phenotype protein levels were determined by Western blotting. The proliferation of VSMCs was analyzed by 3H thymidine-incorporation assay. Results The luciferase activity was significantly decreased in wild-type KLF4 luciferase report gene and miR-29 a expression plasmid co-transfection group. The KLF4 protein expression level（0.36±0.02） was significantly lower in miR-29a-transfected expression plasmid group than that in untransfected and transfection-negative expression plasmid group（1.52±0.06, 1.55±0.05, respectively, P〈0.01）. Meanwhile, compared with untransfected and transfection-negative expression plasmid groups, the contractile phenotype associated protein SM-MHC, SM-22α, calponin expression levels were increased, while the proliferation capability was decreased in miR-29a-transfected expression plasmid group. Conclusion MiR-29 a targets KLF4 and inhibits its expression, thus maintains contractile phenotype of VSMCs, and reduces the cell proliferation ability.

关 键 词：微RNA Krupple样因子4 肌细胞 平滑肌 表型转化 细胞增殖 

分 类 号：R329.41[医药卫生—人体解剖和组织胚胎学]