目的 探讨比索洛尔预处理对缺氧/复氧诱导的心肌细胞凋亡和纤维化的影响，并分析分子机制。方法 构建缺氧/复氧细胞模型，将H9c2细胞分为对照组、模型组、比索洛尔组、细胞外信号调节激酶（ERK1/2）通路激活剂（LM22B-10）组。采用酶联免疫吸附测定法（ELISA）检测细胞中乳酸脱氢酶（LDH）和肌酸激酶同工酶（CK-MB）水平，CCK-8法检测细胞活力，流式细胞术检测细胞凋亡水平，免疫印迹法（Western blotting）法检测凋亡蛋白、纤维化蛋白和ERK1/2信号通路蛋白表达。结果 与模型组比较，比索洛尔组H9c2细胞中LDH和CK-MB水平、细胞凋亡率，切割型半胱氨酸天冬氨酸蛋白水解酶-3（cleaved Caspase-3）、B淋巴细胞瘤-2相关蛋白（Bax）、I型胶原（Col I）、III型胶原（Col III）、α-平滑肌肌动蛋白（α-SMA）、基质金属蛋白酶9（MMP-9）蛋白表达以及磷酸化细胞外信号调节激酶1/2（p-ERK1/2）/（ERK1/2）比值显著降低；细胞活力，B淋巴细胞瘤2（Bcl2）、金属蛋白酶组织抑制因子1（TIMP-1）蛋白表达显著升高（P<0.05）。与比索洛尔组比较，LM22B-10组H9c2细胞中LDH和CK-MB水平、细胞凋亡率，Cleaved Caspase-3、Bax、Col I、Col III、α-SMA、MMP-9蛋白表达以及（p-ERK1/2）/（ERK1/2）比值均显著升高，细胞活力，Bcl-2、TIMP-1蛋白表达均显著降低（P<0.05）。结论 比索洛尔预处理通过抑制ERK1/2信号通路活化减轻缺氧/复氧诱导的心肌细胞凋亡和纤维化。

Objective To investigate the effects of bisoprolol pretreatment on cardiomyocyte apoptosis and fibrosis induced by hypoxia reoxygenation, and to analyze the its mechanisms. Methods Hypoxia/reoxygenation cell model were constructed, H9c2 cells were divided into control group, model group, bisoprolol group, and LM22B-10 group. LDH and CK-MB levels in cells were detected by enzyme-linked immunosorbent assay (ELISA), cell viability was detected by CCK-8 assay, and cell apoptosis was detected by flow cytometry. The expressions of apoptotic proteins, fibrotic proteins and ERK1/2 signaling pathway proteins were detected by Western blotting. Results Compared with model group, LDH and CK-MB levels and apoptosis rate of H9c2 cells, protein expression of cleaved Caspase-3, Bax, Col I, Col III, α-SMA, MMP-9, and (p-ERK1/2)/(ERK1/2) ratio were significantly decreased. Cell viability, Bcl-2, and TIMP-1 protein expressions were significantly increased in bisoprolol group (P < 0.05). Compared with bisoprolol group, LDH and CK-MB levels, apoptosis rate of H9c2 cells, protein expression of cleaved Caspase-3, Bax, Col I, Col III,α-SMA, MMP-9, and (p-ERK1/2)/(ERK1/2) ratio were significantly increased, and cell viability, Bcl-2 and TIMP-1 protein expression were significantly decreased in LM22B-10 group (P < 0.05). Conclusion Bisoprolol pretreatment attenuated hypoxia/reoxygenation induced cardiomyocyte apoptosis and fibrosis by inhibiting the activation of ERK1/2 signaling pathway.

R965

海南省卫生健康行业科研项目（20A200060）