硒对体外心肌细胞过氧化损伤保护和骨架蛋白actin表达的影响

Effect of selenium on the protection of myocardial cells from injuries induced by overloaded reactive oxygen species,and on the expression of actin in myocardial cells

目的探讨硒对H2O2损伤心肌细胞的保护作用以及α-actin和β-actin表达的影响。方法培养乳鼠心肌细胞随机分为对照组,H2O2组,Se 0.05、0.5、1.0和5.0μmol/L组,采用透射电镜观察实验心肌细胞的超微结构,比色法检测心肌细胞培养介质中LDH和MDA含量,Western Blot检测α-actin和β-actin蛋白的表达。结果 Se 0.5μmol/L可减轻心肌细胞超微结构损伤;各加硒组LDH和MDA水平较H2O2组显著降低（P〈0.05）,较对照组显著升高（P〈0.05）,其中Se 0.5μmol/L组LDH和MDA含量在各加硒组中最低;Se 0.5μmol/L组α-actin表达水平较H2O2组升高并高于正常对照组;Se 0.5μmol/L组β-actin表达水平较损伤组升高,低于正常对照组。结论 0.5μmol/L硒对H2O2损伤心肌细胞具有较好的保护作用,可维持和保护α-actin和β-actin的表达,参与细胞骨架蛋白重构。

Objective To investigate the effect of selenium on the protection of myocardial cells from injuries induced by H2O2 and on the expression of α-actin and β-actin in myocardial cells.Method Myocardial cells of suckling mice in the culture were divided into six groups： Controls group（without H2O2 or Se）,H2O2 group,Se 0.05μmol/L group,Se 0.5μmol/L group,Se 1.0μmol/L group and Se 5.0μmol/L group.The ultrastructure of myocardial cells was observed by transmission electron microscope（TEM）,and the LDH and MDA contents in the culture media were determined by colorimetry.The expression of α-actin and β-actin in myocardial cells was detected by Western blot.Results The injury of myocardial cells observed under TEM was attenuated in the 0.5μmol/L Se group.The LDH and MDA contents in the culture media of the Se groups was higher than the control group（P0.05）,but lower than the H2O2 group（P0.05）.The LDH and MDA contents in the 0.5μmol/L Se group were the lowest in all Se groups.The expression level of α-actin and β-actin in the 0.5μmol/L Se group is higher than that in the H2O2 group,even higher than the control group.Conclusion The protective effect of Se on myocardial cells damaged by H2O2 was better in the 0.5μmol/LSe group,which could maintain the expression of α-actin and β-actin,even induce the remolding of cytoskeleton proteins.