组蛋白甲基化酶EZH2对人肥大心肌细胞AC16增殖和凋亡的影响

Effect of histone methylase EZH2 on proliferation and apoptosis of hypertrophic myocardial cells of AC16

目的:探究组蛋白甲基化酶zeste基因增强子同源物2(EZH2)对人肥大心肌细胞AC16增殖和凋亡的影响。方法:通过在AC16细胞培养基中添加血管紧张素Ⅱ构建AC16肥大心肌细胞模型,细胞分为空白对照组、血管紧张素Ⅱ组、空载+血管紧张素Ⅱ组和EZH2过表达+血管紧张素Ⅱ组,并通过荧光定量PCR法检测EZH2和脑钠肽(BNP)基因的表达水平,Western Blot法检测EZH2、组蛋白H3第27位赖氨酸的三甲基化(H3K27me3)和BNP蛋白的表达水平,MTS法检测AC16肥大心肌细胞增殖,以及流式细胞仪检测细胞凋亡。结果:与空白对照组相比,血管紧张素Ⅱ组EZH2和H3K27me3表达水平降低,BNP的表达水平升高,细胞增殖降低,凋亡水平升高(均P<0.001);与空载+血管紧张素Ⅱ组相比,EZH2过表达+血管紧张素Ⅱ组EZH2和H3K27me3表达水平升高,BNP的表达水平降低,细胞增殖水平升高,凋亡水平降低(均P<0.001);血管紧张素Ⅱ组和空载+血管紧张素Ⅱ组相比上述指标差异均无统计学意义(均P>0.05)。结论:组蛋白甲基化酶EZH2对AC16细胞的增殖和凋亡具有影响,为心肌肥厚的治疗以及揭示心肌肥厚的发病机制提供参考。

ObjectiveTo explore the molecular mechanism of the effect of the histone methylase zeste gene enhancer homolog 2(EZH2)on the proliferation and apoptosis of human hypertrophic cardiomyocytes AC16.MethodsThe AC16 hypertrophic cardiomyocyte model was constructed by adding angiotensinⅡto the AC16 cell culture medium.The cells were divided into four groups,including the blank control group,the angiotensinⅡgroup,the empty vector+angiotensinⅡgroup,and the EZH2 overexpression+angiotensinⅡgroup.The expression levels of EZH2 and brain natriuretic peptide(BNP)genes were measured using fluorescent quantitative PCR.The EZH2,trimethylation of lysine at position 27 of histone H3(H3K27me3),and BNP proteins expression were detected by Western Blot.The MTS method was used to detect the proliferation of AC16 cell.The Annexin V-FITC/PI double staining method was used to detect the apoptosis of AC16 cell.ResultsCompared with the blank control group,the expression levels of EZH2 and H3K27me3 in the angiotensinⅡgroup were decreased,the expression level of BNP was increased,cell proliferation was decreased,and apoptosis was increased(all P<0.001).Compared with the empty vector+angiotensinⅡgroup,the expression levels of EZH2 and H3K27me3 in the EZH2 overexpression+angiotensinⅡgroup were increased,the expression level of BNP was decreased,the cell proliferation level was increased,and the apoptosis level was decreased(all P<0.001).There was no significant difference between the angiotensinⅡgroup and the empty vector+angiotensinⅡgroup(all P>0.05).ConclusionsHistone methylase EZH2 has an effect on the proliferation and apoptosis of AC16 cell,providing a reference for the treatment of myocardial hypertrophy and revealing the exact pathogenesis of myocardial hypertrophy.