曲美他嗪预处理对大鼠心肌缺血再灌注后心肌细胞凋亡及超氧化物歧化酶表达的影响

Effect of trimetazidine preconditioning on ischemia-reperfusion injury of rat cardiomyocyte apoptosis and expression of Mn-superoxide dismutase

目的探讨曲美他嗪预处理对心肌缺血再灌注损伤大鼠心肌细胞的保护作用及其机制.方法选取30只健康成年雄性Sprague-Dawley(SD)大鼠,随机分为假手术组(A组,n=10)、心肌缺血再灌注损伤模型组(B组,n=10)、曲美他嗪灌胃预处理组(C组,n=10).观察大鼠心肌组织学改变,测定心肌细胞凋亡,检测血清中肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、超氧化物歧化酶(SOD)、丙二醛(MDA)以及心肌组织中凋亡相关基因[B细胞淋巴瘤/白血病-2(bcl-2)、bcl-2相关X蛋白(bax)、半胱氨酰天冬氨酸特异性蛋白酶(Caspase)-3]表达水平的变化.应用SPSS 19.0统计软件进行分析,多样本均数间比较采用单因素的方差分析(One-way ANOVA),组间两两比较用LSD法.结果与A组比较,B、C组均出现明确的心肌缺血和梗死区域,B组心肌细胞肿胀明显,纤维排列紊乱,C组心肌细胞肿胀明显减轻,细胞凋亡指数显著下降(F=509.000,P<0.01);与B组比较,C组大鼠血清中SOD活性(84.21±6.07)μg/L以及心肌细胞中bcl-2 mRNA表达水平(3.12±1.86)明显升高(t=15.399、16.141,P均<0.01),MDA、CK、CK-MB含量(33.58±3.73)mmol/L,(177.93±5.11)U/L,(50.92±2.94)U/L以及bax和Caspase-3的mRNA表达水平(2.41±0.19,2.34±0.23)明显降低,组间差异均有统计学意义(t=13.563、24.944、13.375、31.696、19.004,P均<0.01).结论曲美他嗪能够有效抑制心肌缺血再灌注损伤大鼠心肌细胞凋亡,对心肌细胞具有一定保护作用.

Objective To investigate the effect protection of trimetazidine pretreatment on myocardial ischemia-reperfusion injury(MIRI)in rats and its mechanism.Methods Thirty health male Sprague-Dawley rats were randomly divided into three groups,Sham group(group A),ischemia-reperfusion group(group B),trimetazidine preconditioning groups(group C).Hematoxylin-eosinstaining(HE)method was used to identify the myocardial tissue.DNA in situ end labeling(TUNEL)was used to detected the apoptosis of cardiomyocytes.The serum levels of creatine kinase(CK),creatine kinase isoenzyme MB(CK-MB),superoxide dismutase(SOD),malondialdehyde(MDA)were measured and the expression of mRNA level of B cell lymphoma/leukemia-2(bcl-2),bcl-2 associated X protein(bax)and cysteinyl aspartate-specific protease(Caspase)-3 were measured by the method of reverse transcription polymerase chain reaction(RT-PCR).Statisticalanalysis of data using the statistical product and service solutions 19.0 software.Results Compared with the group A,group B and C were present clear myocardial ischemia and myocardial infarction area.In group B,the myocardial cells were severely edematous and the fibers were disordered.In group C,the swelling myocardial cells were alleviated and the apoptosis rate of cardiomyocytes was significantly decreased(F=509.000,P<0.01).Compared with the group B,the activity of SOD(84.21±6.07)jxg/L and the expression of bcl-2 at the mRNA level(3.12±1.86)in group C were increased(Z=15.399,16.141,P<0.01).The content of MDA,CK,CK-MB(33.58±3.73)mmol/L,(177.93±5.11)U/L,(50.92±2.94)U/L and The level of bax,Caspase-3 at the mRNA level in group C(2.41±0.19,2.34±0.23)were significantly decreased(i=13.563,24.944,13.375,31.696,19.004,P<0.01).Conclusion Trimetazidine pretreatment can significantly decreases the apoptosis of myocardium induced by MIRI,could protect the myocardium of rats from ischemic reperfusion injury.