microRNA-133a在心肌梗死后心力衰竭大鼠心肌细胞中的表达及抗凋亡作用  

The Anti-apoptosis Effect and Expression of microRNA-133a in Rat Myocardium of Heart Failure After Myocardial Infarction

作　　者：李安莹[1] 杨侃[1] 杨琼[1] 

机构地区：[1]中南大学湘雅三医院心内科,湖南省长沙市410013

出　　处：《中国动脉硬化杂志》2014年第10期1001-1008,共8页Chinese Journal of Arteriosclerosis

摘　　要：目的观察microRNA-133a(miR-133a)在心肌梗死后心衰大鼠心肌细胞中的表达及对细胞凋亡的影响。方法 SD大鼠随机分为四组:1假手术组:仅开胸不结扎冠状动脉;2心肌梗死组:结扎冠状动脉前降支;3r AAV9组:先冠状动脉转染空白病毒r AAV9后再结扎冠状动脉前降支;4miR-133a组:先冠状动脉转染r AAV9-Zs Green-premiR-133a后再结扎冠状动脉前降支。饲养8周后,real-time PCR检测大鼠心肌miR-133a、Transgelin-2(TAGLN2)、Caspase-9、Bcl-2 mRNA水平,免疫组织化学和Western blot检测TAGLN2、Caspase-9、Bcl-2蛋白水平。结果心肌梗死后心衰大鼠心肌组织中miR-133a的表达较假手术组相比显著下降(2.963±0.461比12.518±2.21),TAGLN2和Caspase-9的mRNA及蛋白表达升高,Bcl-2 mRNA和蛋白表达水平降低。冠状动脉注射r AAV9-Zs Green-pre-miR-133a使大鼠心肌miR-133a表达明显上调,TAGLN2和Caspase-9的mRNA及蛋白表达减少,Bcl-2的mRNA和蛋白表达水平增加。结论心肌梗死后心衰大鼠心肌miR-133a表达下调,可能使其对促凋亡基因TAGLN2和Caspase-9的降解和抑制作用减弱,从而促进心肌凋亡的发生;过表达miR-133a可能减少心肌梗死后的心肌凋亡。Aim To observe the anti-apoptosis effect and expression of microRNA-133a（ miR-133a） in rat myocardium of heart failure after myocardial infarction（ MI）. Methods Sprague-Dawley rats were divided into four groups randomly： 1Sham group： rats were dealt with open-chest; 2MI group： rats were operated by left anterior descending coronary artery ligation; 3r AAV9 group： rats were operated by left anterior descending coronary artery ligation after transfected with r AAV9-Zs Green by coronary injection; 4miR-133 a group： rats were operated by left anterior descending coronary artery ligation after transfected with r AAV9-Zs Green-pre-miR-133 a by coronary injection. Feeding for eight weeks,expressions of miR-133 a and mRNA of transgelin-2（ TAGLN2）,Caspase-9 and Bcl-2 were detect by real-time PCR,immunohistochemistry and Western blot were used to determine protein level of TAGLN2,Caspase-9 and Bcl-2.Results The miR-133 a expression of MI group decreased obviously compared with sham group（ 2. 963 ± 0. 461 vs.12. 518 ± 2. 21）. The mRNA and protein level of TAGLN2 and Caspase-9 both increased in MI group versus sham group,while Bcl-2 expression decreased in MI group. The expression of miR-133 a was up-regulated after r AAV9-Zs Green-premiR-133 a coronary injection,the mRNA and protein level of TAGLN2 and Caspase-9 were reduced in the same group,while Bcl-2 expression increased. Conclusions The down-regulation of miR-133 a in failure heart after MI could decrease its degradation and inhibiting effects to TAGLN2 and Caspase-9,thus promote myocardial apoptosis. Myocardial apoptosis may be alleviated by over-expressed miR-133 a.

关 键 词：MicroRNA-133a 心肌梗死 Transgelin-2 CASPASE-9 细胞凋亡 

分 类 号：R363[医药卫生—病理学]