RESUMO
Objective:To 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.Methods:The AC16 hypertrophic cardiomyocyte model was constructed by adding angiotensin Ⅱ to the AC16 cell culture medium. The cells were divided into four groups, including the blank control group, the angiotensin Ⅱ group, the empty vector + angiotensin Ⅱ group, and the EZH2 overexpression + angiotensin Ⅱ group. 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. Results:Compared with the blank control group, the expression levels of EZH2 and H3K27me3 in the angiotensin Ⅱ group 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 + angiotensin Ⅱ group, the expression levels of EZH2 and H3K27me3 in the EZH2 overexpression + angiotensin Ⅱ group 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 angiotensin Ⅱ group and the empty vector + angiotensin Ⅱ group (all P > 0.05). Conclusions:Histone 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.