川芎嗪调控Wnt/β-连环蛋白信号通路对冠心病大鼠心肌细胞凋亡的机制研究

Mechanism of tetramethylpyrazine regulating Wnt/β-catenin signaling pathway on cardiomyocyte apoptosis in rats with coronary heart disease

目的:探讨川芎嗪调控Wnt/β-连环蛋白(Wnt/β-catenin)信号通路对冠心病(CHD)大鼠心肌细胞凋亡的影响。方法:选择成年雄性SD大鼠50只,分为对照组、模型组、川芎嗪低、中、高剂量组,各10只。采用高脂饲料喂养加脂肪乳剂灌胃建立CHD大鼠模型,对照组和模型组大鼠尾静脉注射等体积生理盐水,川芎嗪低、中、高剂量腹腔注射川芎嗪,各组均连续治疗3周。干预后检测各组大鼠心功能和血清乳酸脱氢酶(LDH)、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)水平,采用HE染色观察心肌组织结构,TUNEL检测心肌细胞凋亡情况,RT-qPCR、Western blot法检测心肌组织Wnt3a、β-cateninmRNA及蛋白表达。结果:模型组大鼠心功能低于对照组和川芎嗪低、中、高剂量组(均P<0.05)。模型组大鼠血清LDH、CK、CK-MB水平高于对照组和川芎嗪低、中、高剂量组(均P<0.05)。对照组心肌细胞大小均等,心肌纤维无肿胀、排列紧密,模型组心肌纤维呈现明显肿胀、断裂,细胞排列无规则,并有大量炎症细胞浸润,川芎嗪低、中、高剂量组心肌损伤逐渐改善,细胞水肿变性减少,仅少量炎性细胞浸润。川芎嗪高剂量组心肌组织中Wnt3a、β-cateninmRNA和蛋白表达低于低、中剂量组(均P<0.05)。结论:川芎嗪能改善大鼠心肌细胞的凋亡,减轻细胞损伤,其机制可能与调节Wnt/β-catenin信号通路相关蛋白表达有关。

Objective:To investigate the effect of tetramethylpyrazine regulation of Wnt/β-catenin signaling pathway on cardiomyocyte apoptosis in rats with coronary heart disease(CHD).Methods:A total of 50 adult male SD rats were selected and divided into control group,model group,tetramethylpyrazine low dose group,medium dose group and high dose group with 10 rats each.The CHD rat model was established by high fat feed and fat emulsion intragastric administration.The rats in the control group and model group were injected with equal volume 0.9%sodium chloride solution through tail vein,and tetramethylpyrazine was injected intraperitoneally at low,medium and high doses.All groups were treated continuously for 3 weeks.After intervention,the cardiac function and serum lactate dehydrogenase(LDH),creatine kinase(CK)and CK isoenzyme(CK-MB)levels of rats in each group were detected.Myocardial tissue structure was observed by HE staining,and myocardial apoptosis was detected by TUNEL.The mRNA and protein expressions of Wnt3a andβ-catenin were detected by qRT-PCRand Western blot.Results:The heart function of the model group was lower than that of the control group and the low dose,medium dose and high dose groups(all P<0.05).The serum levels of LDH,CK and CK-MB in model group were higher than those in control group and low,medium and high dose groups(all P<0.05).The myocardial cells of the control group were equal in size,and the myocardial fibers were not swollen and tightly arranged;the myocardial fibers of the model group showed obvious swelling and breakage,and the cell arrangement was irregular,with a large number of inflammatory cells infiltrating;the myocardial damage of the tetramethylpyrazine low,medium and high dose groups was gradually improved,and the cell edema degeneration was reduced,with only a small number of inflammatory cells infiltrating.The mRNA and protein expressions of Wnt3a andβ-catenin in myocardium of tetramethylpyrazine high dose group were lower than those of low and medium dose groups(all P<0.05).Conclusion:Ligustrazine can improve apoptosis and reduce cell damage of rat cardiomyocytes,and its mechanism may be related to the regulation of Wnt/β-catenin signaling pathway related protein expression.