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

Abstract

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. 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. 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. Golgi stress occurs in diabetic cardiomyopathy (DCM), and myocardial protection of exogenous spermine is associated with a reduction in Golgi stress (GAS).