外源性精胺抑制高尔基体应激减轻高糖诱导的心肌损伤*

目的:观察糖尿病心肌病(DCM)是否有高尔基体应激(GAS)参与及外源性精胺心肌保护作用是否与调控GAS有关。方法:60只Wistar大鼠随机分为正常对照组(Control),糖尿病组(T1D,STZ 60 mg/kg一次性腹腔注射)和精胺组(T1D+Sp,精胺5 mg/(kg·d)腹腔注射),饲养12周。H9C2系大鼠心肌细胞随机分为正常对照组(Control,10%的FBS-DMEM培养)、高糖组(HG,10% FBS-DMEM+40 mmol/L葡萄糖)和精胺组(HG +Sp,10% FBS-DMEM+40 mmol/L葡萄糖+5 μmol/L精胺)。ELISA检测大鼠血清心肌肌酸激酶同工酶 (CK-MB)、心肌肌钙蛋白T (cTnT);Western blot测定高尔基体蛋白GOLPH3,GM130以及Cleaved Caspase3蛋白表达;免疫荧光检测GOLPH3细胞定位。结果:动物模型中,与正常组相比,糖尿病组大鼠血糖,血清心肌酶CK-MB和cTnT显著升高明显升高;体重,射血分数(EF)显著降低;心肌超微结构损伤明显(肌丝断裂,润盘消失等);同时GOLPH3和Cleaved Caspase3表达上调,GM130表达下调。细胞模型与大体结果一致,免疫荧光显示高尔基体出现应激性碎片化。外源性精胺处理可显著干预上述改变。结论:给予外源性精胺对糖尿病,诱导的心肌损伤具有干预作用,其机制与减轻高尔基体应激有关。

Exogenous spermine alleviates myocardial injury induced by hyperglycemia by inhibiting golgi stress

Objective: To investigate whether Golgi stress (GAS) is involved in diabetic cardiomyopathy (DCM) and whether myocardial protection of exogenous spermine is associated with regulation of GAS. Methods: Sixty Wistar rats were randomly divided into normal control group (Control), diabetic group (T1D, STZ 60 mg/kg intraperitoneal injection) and spermine group (T1D+Sp, spermine 5 mg/(kg·d) intraperitoneal injection) for 12 weeks. H9C2 rat cardiomyocytes were randomly divided into control group (Control, 10% FBS-DMEM culture), high glucose group (HG, 10% FBS-DMEM+40 mmol/L glucose) and spermine group (HG+Sp, 10% FBS-DMEM+40 mmol/L glucose+5 μmol/L spermine). Rat serum creatine kinase isoenzyme (CK-MB) and cardiac troponin T (cTnT) were detected by ELISA; Golgi protein GOLPH3, GM130 and Cleaved Caspase3 protein expressions were analyzed using Western blot; immunofluorescence was used to detect GOLPH3 cell localization. Results: In the animal model, compared with the normal group, myocardial ultrastructural damage was obvious,the blood glucose, the serum myocardial enzymes CK-MB and cTnT, the expressions of GOLPH3 and cleaved caspase3 were increased or up-regulated significantly,meanwhile, the body weight,the ejection fraction (EF) and the expression of GM130 were decreased or down-regulated markedly in the diabetic group. In the cell model, similar results were obtained. Immunofluorescence showed stress fragmentation of Golgi apparatus. Exogenous spermine treatment could significantly alleviate the above mentioned damages. Conclusion: Golgi stress occurs in diabetic cardiomyopathy (DCM), and myocardial protection of exogenous spermine is associated with a reduction in Golgi stress (GAS).