miR-206-3p通过LXRα调控糖尿病心肌病心肌细胞凋亡的研究

MiR-206-3p regulates cardiomyocyte apoptosis in diabetic cardiomyopathy by targeting LXRα

目的:探究微RNA(miR)-206-3p是否通过调控肝X受体α基因(LXRα)发挥高糖情况下的促心肌细胞凋亡作用.方法:根据不同培养基培养以及是否加LXRα激动剂GW3965将H9C2心肌细胞分为:低糖对照组(5.5mmol/L低糖完全培养基培养)、HM组(加甘露醇的33mmol/L高渗低糖完全培养基培养)、HG组(33mmol/L高糖完全培养基培养)、HG+GW3965-1μM组(HG组加1μmol/L GW3965激动剂).构建miR-206-3p激活及抑制模型后,根据处理方案分为:低糖对照组(转染miR-inhibitor NC质粒+5.5mmol/L低糖培养基)、HG组(转染miR-inhibitor NC质粒+33mmol/L高糖培养基)、HG+inhibitor组(转染miR-206-3p inhibitor质粒+33mmol/L高糖培养基).比较各组间心肌细胞凋亡情况、miR-206-3p和LXRα蛋白质相对表达水平,验证miR-206-3p对LXRα的靶向关系.结果:HG组心肌细胞miR-206-3p表达量显著高于低糖对照组[(6.775±0.615)比(0.976±0.781),P=0.001],HG+miR-206-3p inhibitor组凋亡细胞水平显著低于HG组[(0.059±0.001)比(0.123±0.074),P=0.001];双荧光素酶活性实验证实miR-206-3p同LXRα相结合.激活LXRα可减少高糖导致的心肌细胞凋亡.结论:高糖情况下miR-206-3p表达显著升高并通过靶向下调LXRα促进了高糖介导的心肌细胞凋亡.

Objective:To explore whether microRNA(miR)-206-3 p can promote cardiomyocyte apoptosis under high glucose condition via targeting liver X receptor α gene(LXRα). Methods:H9 C2 cardiomyocytes were grouped according to different media cultures and whether or not LXRα agonist GW3965 was added: low glucose control group(5.5 mmol/L low glucose complete medium culture), HM group(33 mmol/L mannitol-added high osmotic low glucose complete medium culture), HG group(33 mmol/L high glucose complete medium culture) and HG + GW3965-1μM group(HG group plus 1μmol/L GW3965 agonist). After miR-206-3 p mimic and inhibitor model were established, they were divided according to treatment program: low glucose control group(transfected miR-inhibitor NC plasmid + 5.5 mmol/L low glucose medium), HG group(transfected miR-inhibitor NC plasmid + 33 mmol/L high glucose medium) and HG + inhibitor group(transfected miR-206-3 p inhibitor plasmid + 33 mmol/L high glucose medium). Cardiomyocyte apoptosis condition, relative expression levels of miR-206-3 p and LXRα protein were compared among all groups, and the targeting relationship of miR-206-3 p to LXRα was verified. Results:Expression amount of miR-206-3 p of cardiomyocyte in HG group was significantly higher than that of low glucose control group [(6.775±0.615) vs.(0.976±0.781), P=0.001];cell apoptotic level of HG+miR-206-3 p inhibitor group was significantly lower than that of HG group [(0.059±0.001) vs.(0.123±0.074), P=0.001];dual luciferase activity experiment proved that miR-206-3 p was combined with LXRα. LXRα activation can reduce cardiomyocyte apoptosis caused by high glucose. Conclusion:On high glucose condition, miR-206-3 p expression significantly rises and target downregulates LXRα, then promoting cardiomyocyte apoptosis mediated by high glucose.