3-氨基苯甲酰胺对心肌缺血再灌注大鼠心肌损伤的保护作用研究

Protective effect of 3-aminobenzamide on myocardial injury in rats with myocardial ischemia-reperfusion injury

目的探究3-氨基苯甲酰胺预处理对大鼠心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury,MIRI)的保护作用。方法大鼠通过结扎左前降支血管实现缺血,缺血40 min后将结扎线松解,实现再灌注120 min,建立MIRI模型;取10只为假手术组(只穿线不结扎)。将模型大鼠随机分为模型组、对照组和实验组,每组10只。对照组于缺血40 min后,腹腔注射20 mg·kg^(-1)3-AB,实现再灌注120 min后再次腹腔注射20 mg·kg^(-1)3-AB;实验组于再灌注120 min后腹腔注射20 mg·kg^(-1)3-AB+1 mg·kg^(-1) AG490;模型组和假手术组均腹腔注射等量0.9%NaCl。比较各组血清心肌酶谱水平,心肌细胞凋亡情况,并用蛋白质印迹法检测核酶多腺苷二磷酸核糖聚合酶1(polyadenosine diphosphate ribose polymerase 1,PARP-1)蛋白及Janus激酶2/转录激活因子3(Janus kinase 2/activator of transcription 3,JAK2/STAT3)通路蛋白的表达水平。结果实验组、对照组、模型组和假手术组的乳酸脱氢酶分别为(5061.83±759.13),(4533.79±680.08),(5737.93±860.68)和(4135.26±620.30)U·L^(-1),肌酸激酶同工酶水平分别为(579.77±86.96),(516.58±77.50),(656.87±98.53)和(496.35±75.46)U·L^(-1),心肌细胞凋亡率分别为(19.33±3.68)%,(13.58±2.06)%,(26.96±4.05)%和(9.87±1.47)%,心肌组织PARP-1蛋白相对表达水平分别为0.89±0.15,0.57±0.09,1.12±0.17和0.33±0.05,p-JAK2/JAK2分别为0.50±0.08,0.67±0.11,0.25±0.03和0.96±0.15,p-STAT3/STAT3分别为0.45±0.07,0.80±0.13,0.16±0.03和0.99±0.15。实验组和对照组的上述指标与模型组比较,实验组的上述指标与对照组比较,差异均有统计学意义(均P<0.05)。结论3-氨基苯甲酰胺预处理可通过下调PARP-1表达,促进JAK2/STAT3通路活化,进而抑制心肌细胞凋亡,从而发挥对大鼠MIRI的保护作用。

Objective To explore the protective effect of 3-aminobenzamide preconditioning on myocardial ischemia-reperfusion injury(MIRI)in rats.Methods The rats achieved ischemia by ligating the left anterior descending vessels,releasing the ligation line for 40 min,and achieved reperfusion for 120 min to establish the MIRI model.Ten rats were selected as the sham-operation group(only thread without ligation).The model rats were randomly divided into model,control and experimental groups with 10 cases per group.Control group received 20 mg·kg^(-1)3-AB with intraperitoneal injection after ischemia 40 minutes,and 20 mg·kg^(-1)3-AB was intraperitoneally injected again after reperfusion 120 minutes.Experimental group was intraperitoneally injected with 20 mg·kg^(-1)3-AB+1 mg·kg^(-1) AG490 after reperfusion 120 min.Model and sham-operated groups were intraperitoneally injected with the same amount of 0.9%NaCl.The levels of serum myocardial enzyme spectrum and cardiomyocyte apoptosis were compared among four groups.The protein expression levels of polyadenosine diphosphate ribose polymerase 1(PARP-1)and Janus kinase 2/activator of transcription 3(JAK2/STAT3)were detected by Western blotting.Results The levels of lactic dehydrogenase in the experimental,control,model and sham-operation groups were(5061.83±759.13),(4533.79±680.08),(5737.93±860.68)and(4135.26±620.30)U·L^(-1);creatine kinase isomer-MB levels were(579.77±86.96),(516.58±77.50),(656.87±98.53)and(496.35±75.46)U·L^(-1);apoptosis rates of cardiomyocytes were(19.33±3.68)%,(13.58±2.06)%,(26.96±4.05)%and(9.87±1.47)%;the levels of p-JAK2/JAK2 were 0.89±0.15,0.57±0.09,1.12±0.17 and 0.33±0.05;p-STAT3/STAT3 were 0.45±0.07,0.80±0.13,0.16±0.03 and 0.99±0.15.There were significant differences in the above-mentioned indexes between the experimental and control groups and the model group(all P<0.05).There differences were statistically significant in the above indexes between the experimental group and the control group(all P<0.05).Conclusion 3-aminobenzamide preconditioning can protect rat MIRI by down-regulating the expression of PARP-1,promoting the activation of JAK2/STAT3 pathway,and then inhibiting cardiomyocyte apoptosis.