Effect of tanshinoneⅡ A on expression of protein S100A1in acute myocardial ischemia rats / 中国中西医结合急救杂志

ABSTRACT

ObjectiveTo investigate the protective effect of tanshinoneⅡA on the expression of S100A1 protein after acute myocardial ischemia injury in rats.Methods Sixty Wistar rats were randomly divided into sham operation group, acute myocardial ischemia model group and tanshinoneⅡA pretreatment group by random number table. The acute myocardial ischemia model was established by thoracotomy and penetration of a thread and occlusion around the root part of the left anterior descending coronary artery, while the sham operation group was established only by thoracotomy and penetration of a thread around the root part of that artery but without occlusion; 3 days before the operation, in the tanshinoneⅡA pretreatment group, intraperitoneal injection of tanshinoneⅡA solution(at a dose of 1.5 mg/kg) was applied, while in the sham and acute myocardial ischemia groups, intraperitoneal injection of an equal volume of saline was given. Myocardial cell apoptosis was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL), the levels of serum superoxide dismutase (SOD), malondialdehyde(MDA), creatine kinase(CK), lactate dehydrogenase(LDH) and S100A1 protein were examined and the level of expression of S100A1 protein in myocardial tissue was assayed by immunohistochemical staining and Western Blot.Results Compared with the sham operation group, the myocardial cell apoptosis rate, the contents of MDA, CK, LDH, S100A1 and the level of S100A1 expression in myocardial ischemia group and tanshinoneⅡA pretreated group were significantly increased, while SOD activity was decreased obviously; compared with the myocardial ischemia model group, the myocardial cell apoptosis rate, the contents of MDA, CK, LDH, S100A1 and the level of S100A1 protein expression were significantly reduced〔apoptosis rate(32.1±4.2)% vs.(72.4±5.4)%, MDA(μmol/L) 9.1±2.2 vs. 17.3±5.2, CK(U/L) 83.3±12.2 vs. 107.5±12.4, LDH (μmol·s-1·L-1) 84.0±16.4 vs. 114.4±16.0, S100A1(μg/L) 37.6±6.0 vs. 78.4±8.6,P<0.05 orP<0.01〕, while the activity of SOD was increased markedly in tanshinoneⅡA pretreated group(kU/L72.8±10.2 vs. 49.6±8.8,P<0.01). TUNEL staining showed that in the myocardial ischemia model group and tanshinoneⅡA pretreated group, the myocardial cells represented positive staining(brown-yellow in color), irregular in shape with nuclear pyknosis, cell detachment from the surrounding tissue and other characteristics. And in sham operation group,the staining of majority of cells was negative. The results of immunohistochemistry showed that S100A1 protein staining was relatively deep in the myocardial ischemia model group and tanshinoneⅡA pretreated group, and in the latter group, the color of S100A1 protein positive staining was not as deep as that in the former group. Western Blot showed that the S100A1 protein expression in myocardial ischemia model group was 2.8 folds of that of the sham operation group, while the S100A1 protein expression in tanshinoneⅡA pretreated group was significantly decreased compared with that of myocardial ischemia model group(bothP<0.05),which was 1.5 folds of that of the sham operation group.ConclusionTanshinoneⅡA may play a role in inhibiting the expression of S100A1 protein to protect against acute myocardial ischemia injury, suggesting that this agent have a potential effect for treatment of myocardial ischemia.