ABSTRACT
@#To study the protective effects of Roudoukou-8 San extract on hypoxia/reoxygenation injury of cardiac myocytes and its relationship with tyrosine protein kinase 2(JAK2)/signal transducer and activator 3(STAT3)signaling pathway, hypoxia/reoxygenation injury model of H9c2 cells was built by sodium dithionite(Na2S2O4). The vitality of the cells was tested by CCK-8; the contents of lactate dehydrogenase(LDH), creatine phosphate kinase(CK)and aspartate aminotransferase(AST)in cell culture medium were tested by fully automatic biochemical analyzer; the contents of catalase(CAT), superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)in cells were tested by kits; cell apoptosis degree was tested by hoechst staining. And the protein expressions of JAK2, p-JAK2, STAT3, p-STAT3, Bcl-2 and Bax in myocardial cells of each group were tested by Western blot. Hypoxia for 1 hour and reoxygenation for 3 hours of 2 mmol/L Na2S2O4 caused damage of about 50% H9c2 cells. Compared with the model group, the extracts of Roudoukou-8 San with different concentrations could increase the viability of cells. Besides, contents of CK, LDH and AST in cell culture medium were decreased significantly, while contents of CAT, SOD and GSH-Px were increased significantly. At the same time, the expression of p-JAK2, p-STAT3 and Bcl-2 were significantly increased and that of Bax was significantly decreased. The effects of Roudoukou-8 San extract could bereduced by AG490 blocker. Therefore, Roudoukou-8 San extract possesses protective effects on Na2S2O4 induced-hypoxia/reoxygenation injury of cardiac myocytes through JAK2/STAT3 signaling pathway.
ABSTRACT
@#To study the effects of Roudoukou-8 San against hydrogen peroxide-induced cardiomyocyte in neonatal rats and to explore its mechanism. Cardiomyocytes were isolated and cultivated by neonatal rats and the injure models were established by H2O2. Methyl thiazolyl tetrazolium(MTT)assay was used to detect the protective effects of Roudoukou-8 San on H2O2-induced cardiomyocyte. The effects of Roudoukou-8 San on myocardium morphology were observed under inverted microscope. The contents of lactate dehydrogenase(LDH), creatine kinase(CK)and aspartate aminotransferase(AST)in cell culture medium were determined by Automatic biochemical instrument; The levels of malonydialdehyde(MDA), superoxide dismutase(SOD)and NO in the cells were detected by kit method. The apoptotic morphology of cardiomyocytes was observed by Hoechst fluorescence staining. Cell apoptosis were measured by Annexin V and PI double staining and flow cytomety. 100μmol/L H2O2 for 2 h could cause about 50% of myocardial injury. In the inverted optical microscope, H2O2 model group showed increased cell gap, decreased cell count, cell cytoplasmic vacuoles and other obvious damage. Roudoukou-8 San protected cell from H2O2-induced morphlogical improved in different degrees, reduced the release of LDH, CK and AST content, reduced the content of MDA, NO in myocardial cells significantly and increased the activity of SOD. Roudoukou-8 San energy significantly inhibited H2O2 damage myocardial cell apoptosis. Our study suggested that Roudoukou-8 San can protect cardiomyocyte from H2O2-induced injury by improving the cell viability, reducing oxidative stress injury, inhibiting inflammatory reaction and inhibiting cell apoptosis.