牡荆素对CVB3病毒性心肌炎心肌细胞损伤的影响及机制

Effect of Vitexin on myocardial cell injury of viral myocarditis induced by Coxsackie B3 virus

目的:研究牡荆素对柯萨奇B3病毒(CVB3)诱导的病毒性心肌炎心肌细胞凋亡和炎症的影响及其可能作用机制。方法:体外培养人心肌细胞AC-16,将细胞分为5组:正常组、病毒组、牡荆素低剂量组(10 mg/kg)、牡荆素中剂量组(30 mg/kg)和牡荆素高剂量组(50 mg/kg),正常组常规培养,病毒组和牡荆素组经CVB3诱导构建病毒性心肌炎细胞模型,牡荆素各剂量组分别给予不同剂量牡荆素处理;MTT法检测细胞增殖活性;流式细胞仪检测细胞凋亡情况;Western blotting检测凋亡相关蛋白Bcl-2、Bax及p-p38MAPK蛋白的表达;ELISA法检测细胞培养液中白细胞介素1β(IL-1β)和肿瘤坏死因子α(TNF-α)的表达水平。结果:与正常组比较,病毒组心肌细胞增殖活力降低,凋亡率升高,细胞中Bcl-2蛋白相对表达水平降低,Bax蛋白相对表达水平升高,细胞培养液中IL-1β和TNF-α水平升高,细胞中p-p38 MAPK蛋白相对表达量升高(P<0.05);与病毒组比较,牡荆素低、中、高剂量组心肌细胞增殖活力增强,细胞中Bcl-2蛋白相对表达水平升高,凋亡率、Bax蛋白相对表达水平、细胞培养液中IL-1β和TNF-α水平、p-p38 MAPK蛋白均降低(均P<0.05),并具有一定的剂量依赖性。结论:牡荆素能够抑制CVB3诱导的心肌细胞凋亡和炎症,促进细胞增殖,其作用机制可能与抑制p38 MAPK信号通路激活有关。

Objective: To study the effect of Vitexin on apoptosis and inflammation of myocarditis induced by Coxsackie B3 virus(CVB3) and its possible mechanism. Methods Human cardiomyocytes AC-16 were cultured in vitro, and the cells were divided into five groups: normal group, virus group and Vitexin low dose group(10 mg/kg), Vitexin middle dose group(30 mg/kg), Vitexin high dose group(50 mg/kg);normal group was routinely cultured;virus group and Vitexin group were induced by CVB3 to construct viral myocarditis cell model;and the Vitexin group was treated with different doses of Vitexin respectively. Cell proliferation activity was detected by MTT assay. Flow cytometry was used to detect apoptosis. Western blotting was used to detect the expression of apoptosis-related proteins Bcl-2 and Bax. ELISA was used to detect interleukin1β(IL-1β) and tumor necrosis factorα(TNF-α) in cell culture medium. Results Compared with the normal group, myocardial cell proliferation activity and the expression of Bcl-2 protein were decreased, whereas the apoptosis rate, the expression of Bax andpp38 MAPK protein, and the levels of IL-1β and TNF-α in cell culture fluid were increased inthe viral group(P<0.05). Compared with the virus group, the proliferation activity of cardiomyocytes and the Bcl-2 protein levelwere elevated, whilethe apoptosis rate, the Bax and p-p38 MAPKprotein expressions, and the levels of IL-1β and TNF-α in the cell culture medium were reduced in Vitexin-treated groupsin a dose-dependent manner(P<0.05).Conclusion: Vitexin could inhibit the apoptosis and inflammation of cardiomyocytes induced by CVB3 and promote cell proliferation, and the mechanism may be related to inhibiting the activation of p38 MAPK signaling pathway.