参芪益心方对ISO诱导的心肌细胞凋亡及内质网应激的影响

Effects of Shenqi Yixin formula on isoprenaline induced cardiomyocyte apoptosis and endoplasmic reticulum stress

目的探讨参芪益心方对异丙肾上腺素(isoprenaline,ISO)诱导的心肌细胞凋亡及内质网应激(endoplasmic reticulum stress,ERS)的干预效果。方法40只SD大鼠随机分为5组,即对照组(Con组)、模型组(ISO组)、曲美他嗪治疗组(QM组)、参芪益心方低剂量治疗组(SL组)、参芪益心方高剂量治疗组(SH组),每组各8只。除Con组外,其余各组大鼠皮下注射ISO诱导心肌损伤,Con组大鼠给予等量生理盐水,共4周;第3周开始QM组给予曲美他嗪混悬液5mg/(kg·d),SL组给予参芪益心方水煎剂10g/(kg·d),SH组给予参芪益心方水煎剂20g/(kg·d),Con组和ISO组给予等量生理盐水灌胃。实验4周末比较各组大鼠的心电图、超声心动图指标,心肌组织病理切片,肌醇需求酶1(inositol-requiring enzyme 1,IRE 1)、X盒结合蛋白1(X-box binding protein 1,XBP1)、cleaved caspase-3、p53正向凋亡调控因子(p53 upregulated modulator of apoptosis,PUMA)水平。结果与Con组比较,ISO组大鼠心电图出现异常Q波,ST段抬高,心率增快(P<0.05),左室射血分数、左心室短轴缩短率明显降低,心功能下降(P<0.05);SL组和SH组较ISO组心功能改善(P<0.05)。ISO组心肌结构紊乱,纤维化程度明显增强,可见纤维断裂与空泡样变性;SL组和SH组较ISO组纤维化程度降低,心肌纤维断裂和空泡减少。ISO组大鼠心肌组织的IRE1、XBP1、cleaved caspase-3、PUMA蛋白水平均显著高于Con组(P<0.001);SH组和SL组大鼠心肌组织的IRE1、XBP1、cleaved caspase-3、PUMA蛋白水平均显著低于ISO组(P<0.05),且SH组降低较SL组更显著。结论ERS参与ISO诱导的心肌损伤,参芪益心方可降低IRE1、XBP1、cleaved caspase-3、PUMA水平,改善心肌损伤,且高剂量效果更显著。

Objective To explore the effect of Shenqi Yixin formula on the isoproterenol(ISO)induced cardiomyocyte apoptosis and endoplasmic reticulum stress(ERS).Methods 40 SD rats were randomly divided into five groups:control group(Con group),model group(ISO group),trimetazidine group(QM group),low-dose treatment group of Shenqi Yixin formula(SL group)and high-dose treatment group of Shenqi Yixin formula(SH group),each group had 8 rats.Myocardial injury was induced by subcutaneous ISO injection in all groups except Con group,and the rats in Con group were given the same amount of normal saline for a total of 4 weeks.Starting from the third week,trimetazidine suspension was given 5mg/(kg·d)in QM group,Shenqi Yixin formula was given 10g/(kg·d)in SL group,Shenqi Yixin formula was given 20g/(kg·d)in SH group,Con group and ISO group were given the same amount of normal saline by intragastric administration.At the end of experiment 4 weeks,electrocardiograph and echocardiogram indexes,myocardial histological sections,inositol-requiring enzyme 1(IRE1),X-box binding protein 1(XBP1),cleaved caspase-3,and p53 upregulated modulator of apoptosis(PUMA)levels were compared among the groups.Results Compared with Con group,the rats in ISO group showed abnormal Q wave,ST segment elevation and increased heart rate(P<0.05),left ventricular ejection fraction,left ventricular fractional shortening significantly decreased,and cardiac function decreased(P<0.05).The cardiac function of the SL group and SH group were better than those of ISO group(P<0.05).In ISO group,the myocardial structure was disordered,the degree of fibrosis was significantly enhanced,and fiber breakage and vacuole-like degeneration could be seen.The degree of fibrosis in SL group and SH group were lower than those in ISO group,myocardial fiber breakage and vacuolation decreased.The protein levels of IRE1,XBP1,cleaved caspase-3 and PUMA in myocardial tissue of rats in ISO group were significantly higher than those in Con group(P<0.001).The protein levels of IRE1,XBP1,cleaved caspase-3 and PUMA in SH and SL groups were significantly lower than those in ISO group(P<0.05),and the reduction in SH group was more significant than that in SL group.Conclusion ERS was involved in ISO-induced myocardial injury.Shenqi Yixin formula reduced IRE1,XBP1,cleaved caspase-3,PUMA levels,and improved myocardial injury,and the effect was more significant at high doses.