摘要
目的探讨慢病毒介导的P38丝裂原活化蛋白激酶（P38MAPK）短发夹环RNA（shRNA）对醛固酮过负荷大鼠心肌梗死（心梗）后心功能的影响并探讨其机制。方法制作醛固酮过负荷大鼠心梗模型，构建慢病毒P38MAPKshRNA（PGLV-shRNA）测序鉴定并经尾静脉注射，超声评价心功能，检测心肌细胞凋亡、P38MAPKmRNA、蛋白及Caspase-3蛋白的表达。结果假手术组、PGLV空载组和PGLV-SHRNA组细胞凋亡指数分别为（15．20±2．18）％、（31．26±4．45）％和（22．35±3．59）％；醛固酮过负荷大鼠心梗后心脏收缩功能显著降低，伴随心肌细胞凋亡增加、P38MAPKmRNA、蛋白及caspase-3蛋白表达上调（P〈0．01）。PGLV-shRNA明显改善心梗后的心脏功能，减少心肌细胞凋亡P38MAPKmRNA、蛋白及caspase-3表达（P〈0．05）。结论醛固酮过负荷大鼠心梗后心脏功能降低与P38MAPK信号通路介导的心肌细胞凋亡相关，PGLV-shRNA抑制细胞凋亡，改善心梗后的心脏功能。
Objective To investigate the effects of p38 mitogen-activated protein kinase （MAPK） short hair RNA （shRNA） delivered by lentiviral vectors （pGLV） on cardiac function after myocardial infarction （MI） in aldosterone overload rats and to explore the mechanism. Methods Aldosterone overload rat myocardial infarction model was obtained by ligating the left anterior descending coronary artery. The pGLV-shRNA was constructed, sequenced and injected into rats via tail vein. Rats were divided into 3 groups： pGLV-shRNA group （n=6）, pGLV- shRNA -NC group （n=6, contained a nonsense shRNA） and the sham-operation group （n=6）. Cardiac function was measured by cardiac ultrasound. Apoptosis was assessed by transferase （TdT）-mediated biotin-16- dUTP nick-end labelling （TUNEL）. The p38 MAPK mRNA expression was analyzed by RT-PCR. The protein expressions of p38 MAPK and caspase-3 were detected by Western blot. Results Compared with the sham operation group, cardiac systolic function was reduced and myocardial apoptosis index was significantly increased [（31.26 ± 4.45）% vs. （15.20 ±2.18）%, P〈0.01] in pGLV- shRNA -NC group. The mRNA and protien expressions of p38MAPK and caspase 3 protein expression were significantly increased in pGLV- shRNA -NC group （all P%0.01）. Compared with pGLV-shRNA-NC group, cardiac function was improved, myocardial cell apoptosis index was reduced [（22.35±3.59）% vs. （31.26 ± 4.45）%, P〈0.05], and the mRNA and protien expressions of p38MAPK and caspase 3 protein expression were decreased in pGLV-shRNA group （all P%0.05）. Conclusions Cardiac dysfunction is associated with p38MAPK-mediated myocardial apoptosis in aldosterone overload MI rats. pGLV-shRNA may inhibit cardiomyocyte apoptosis and improve post- MI cardiac function.
出处
《中华老年医学杂志》
CAS
CSCD
北大核心
2013年第6期671-674,共4页
Chinese Journal of Geriatrics
基金
胡北省自然科学基金（2010CDB06806）,广东省医学科研基金（A2007022）
