薯蓣皂素通过抑制内质网应激对柯萨奇病毒诱导心肌细胞损伤的影响

Effect of Diosgenin on Coxsackievirusinduced Cardiomyocyte Injury via Inhibition of Endoplasmic Reticulum Stress

柯萨奇病毒B3(Coxsackievirus B3,CVB3)是病毒性心肌炎最常见的致病毒株,CVB3感染诱导心肌细胞损伤的作用与激活内质网应激(Endoplasmic reticulum stress,ERS)有关。薯蓣皂素(Diosgenin,DG)通过抑制ERS减轻心肌细胞缺氧损伤,但DG对CVB3感染诱导心肌细胞损伤的保护作用及机制尚不清楚。因此,本研究将分析DG通过抑制ERS对CVB3诱导心肌细胞损伤的影响及机制。培养心肌H9c2细胞并分组,对照组用不含药物和病毒的培养基处理,模型组用含有CVB3的培养基处理,不同浓度DG用含有10、20、40 mg/L DG及CVB3的培养基处理,溶剂对照组用含有对照溶剂二甲基亚砜(DMSO)的培养基处理,溶剂+模型组用含有DMSO和CVB3的培养基处理,溶剂+DG组用含有DMSO、CVB3及40 mg/L DG的培养基处理,激动剂组用含有ERS激动剂、CVB3及40 mg/L DG的培养基处理。检测培养基中乳酸脱氢酶(Lactic dehydrogenase,LDH)、肌酸激酶(Creatine kinase,CK)、肌酸激酶同工酶(Creatine Kinase isoenzymeMB,CKMB)的含量,细胞活力A490,细胞凋亡率,细胞中ERS标志蛋白葡萄糖调节蛋白78(Glucoseregulated protein 78,GRP7)、C/EBP同源蛋白(C/EBP homologous protein,CHOP)、磷酸化cJun氨基末端激酶(Phosphorylation cJun nterminal kinase,pJNK)、裂解型caspase12的表达。结果显示,与对照组比较,模型组培养基中LDH、CK、CKMB的含量、细胞凋亡率、细胞中GRP78、CHOP、pJNK、裂解型caspase12的表达水平增加,细胞活力A490降低;与模型组比较,不同浓度DG组培养基中LDH、CK、CKMB的含量、细胞凋亡率、细胞中GRP78、CHOP、pJNK、裂解型caspase12的表达水平降低,细胞活力A490增加且DG浓度越高,上述变化越显著;与溶剂+DG组比较,激动剂+DG组培养基中LDH、CK、CKMB的含量、细胞凋亡率、细胞中GRP78、CHOP、pJNK、裂解型caspase12的表达水平增加,细胞活力A490降低。以上结果表明,DG能够减轻CVB3诱导心肌细胞损伤及凋亡,抑制ERS是可能相关的分子机制。

Coxsackievirus B3(CVB3)is the most common pathogenic strain of viral myocarditis.The effect of CVB3 infection on cardiomyocyte injury is related to activation of endoplasmic reticulum stress(ERS).Diosgenin alleviates hypoxic injury to cardiomyocytes by inhibiting ERS.However,the protective effect of diosgenin on CVB3 infectioninduced cardiomyocyte injury and its mechanism of action are not known.We analyzed the effect and mechanism of action of diosgenin on CVB3induced cardiomyocyte injury by inhibiting ERS.Myocardial(H9c2)cells were cultured and divided into groups.The control group was treated with medium free of drugs or viruses.The model group was treated with medium containing CVB3 and diosgenin(10,20,40 mg/L).The solvent control group was treated with medium containing the control solvent dimethyl sulfoxide(DMSO).The solvent+model group was treated with medium containing DMSO and CVB3.The solvent+diosgenin group was treated with medium containing DMSO,CVB3 and diosgenin(40 mg/L).The agonist+diosgenin group was treated with medium containing an ERS agonist,CVB3 and diosgenin(40 mg/L).The content of lactate dehydrogenase(LDH),creatine kinase(CK),and creatine kinase isoenzymeMB(CKMB)in the medium,viability of A490 cells,and apoptosis rate,as well as expression of the ERS marker glucoseregulated protein 78(GRP78),C/EBP homologous protein(CHOP),phosphorylated CJun aminoterminal kinase(pJNK),and cleaved caspase12 in cells were determined.Compared with the control group,the content of LDH,CK,and CKMB in the medium,apoptosis rate,and expression of GRP78,CHOP,pJNK,and cleaved caspase12 in cells of the model group increased,while the viability of A490 cells decreased.Compared with the model group,the content of LDH,CK,and CKMB in the medium,apoptosis rate,and expression of GRP78,CHOP,pJNK,and cleaved caspase12 in cells of the model group decreased,while the viability of A490 cells increased.Compared with the solvent+diosgenin group,the content of LDH,CK,and CKMB in the medium,apoptosis rate,and expression of GRP78,CHOP,pJNK,and cleaved caspase12 in cells of the model group increased,while the viability of A490 cells decreased in the agonist+diosgenin group.These results suggest that diosgenin alleviates the injury to and apoptosis of cardiomyocytes induced by CVB3,and that ERS inhibition may be the related molecular mechanism.