Protective Effects And Mechanisms Of Scutellarin And Benzyl Ester Derivant Of Scutellarin Against Hypoxia Injury In Cardiocytes

Objectives: We researched the protective effects and its mechanisms of sutellarin and benzyl ester derivant of sutellarin on cultured myocardial cells of neonatal rats in hypoxia injury.Methods: We used primary cultured SD neonatal rat (1-3d) cardiac myocytes to explore, ascertained the best time of hypoxia through MTT method and then established the model of hypoxia. The cultured cardiocytes growing in good condition were divided randomly into control group, hypoxia injury model group and intervention group of sutellarin and benzyl ester derivant of sutellarin (100μmol/L, 50μmol/L, 25μmol/L). After hypoxia for 6h, the release of LDH, the content of NO, the activities of SOD and productions of MDA in cells were measured in each group for investigating the effects of sutellarin and benzyl ester derivant of sutellarin on the cultured cardiocytes injured by hypoxia. By HE staining, we studied the effect of sutellarin and benzyl ester derivant of sutellarin on the apoptosis induced by hypoxia in cultured neonatal rat cardio myocytes at morphological level. By Hochest-PI staining and flow cytometry, we detected the sutellarin and benzyl ester derivant of sutellarin have the protected effect on cultured neonatal rat cardio myocytes in hypoxia injury. Changes in expression of Bcl-2, Bax, Cytochrome c, Caspase-3 mRNA were detected by PR-PCR. Changes in expression of Bcl-2, Bax, Cytochrome c, Caspase-3 protein were detected by Western-blot.Results:1 During six hours of cardiocytes hypoxia injury, the cells viability in model group had been degraded in the largest extent, so we ascertained six hours the best time of hypoxia. 2 Campaired with the control group, the modle group appears significant growth on leakage of LDH(P<0.01) and content of MDA(P<0.01), reduce on release of NO(P<0.01) and the activity of SOD(P<0.01). Most dose of sutellarin and benzyl ester derivant of sutellarin could significantly reduce the release of LDH(P<0.01), increase the content of NO(intervention group of 100μmol/L, 50μmol/L, P<0.01), increase SOD activities (intervention group of 100μmol/L, 50μmol/L, P<0.01) and inhibit MDA productions in cells (intervention group of 100μmol/L, P<0.05) during hypoxia injury.3 In morphology the injured cells appeared significant change, such as swelling, fragmental or the condensing of nucleus. With the intervention of sutellarin and benzyl ester derivant of sutellarin (100μmol/L), all these injurious changes could be attenuated in large degree.4 Campaired with the control group, the modle group appears significant growth of the percentage of (P<0.01). Sutellarin and benzyl ester derivant of sutellarin could remarkably decrease the percentage of apoptotic cells induced by hypoxia (each dose of sutellarin , and benzyl ester derivant of sutellarin at 100μmol/L, 50μmol/L, P<0.01).5 Sutellarin and benzyl ester derivant of sutellarin could up-regulated the expression of Bcl-2 protein (each dose of sutellarin, and benzyl ester derivant of sutellarin at 100μmol/L, 50μmol/L, P<0.01), down-regulated the expression of Bax protein (each dose of sutellarin, and benzyl ester derivant of sutellarin at 100μmol/L, 50μmol/L, P<0.01), cytochrome c protein (P<0.01) and caspase-3 proteinin (each dose of sutellarin, and benzyl ester derivant of sutellarin at 100μmol/L, 50μmol/L, P<0.01) in cardiac myocytes injured by hypoxia.Conclusions: Sutellarin and benzyl ester derivant of sutellarin could improve the myocardial function and modify the cellular configuration injury during hypoxia of neonatal rat cardiac myocytes. The protective mechanisms are possibly the effect of antioxidan and the attenuation of apoptosis.