金樱子总黄酮对过氧化氢损伤内皮细胞的保护作用

Protective Effect of Rosa laevigata Michx Total Flavonoids on Vascular Endothelial Cells Injury Induced by Hydrogen Peroxide

目的研究金樱子总黄酮对过氧化氢损伤人脐静脉内皮细胞(human umbilical vascular endothelial cells,HUVEC)的保护作用。方法体外培养HUVEC,用不同浓度H2O2诱导HUVEC损伤构建内皮细胞氧化损伤模型,采用MTT法测定各组细胞活力;用酶标仪测定各组细胞中超氧化物歧化酶(SOD),过氧化氢酶(CAT),谷胱甘肽过氧化物酶(GSH-Px)活力;Western Blot检测各组细胞凋亡抑制蛋白Bcl-2及促凋亡蛋白Bax的表达情况。结果 MTT观察结果表明600μmol/L H2O2为构建氧化损伤HUVEC模型的合适浓度。与H2O2损伤组比较,不同浓度总黄酮预处理组的细胞活力均显著升高(P<0.01);不同浓度总黄酮预处理组细胞培养液中的SOD、CAT和GSH-Px活性均明显增加(P<0.01),且随着总黄酮浓度的增大而升高。与H2O2损伤组比较,0.12 mg/ml处理组Bcl-2蛋白表达无显著升高,0.24 mg/ml和0.48 mg/ml处理组Bcl-2蛋白表达水平均显著升高(P<0.05);而各浓度预处理组Bax蛋白表达水平显著降低(P<0.05或P<0.01)。结论金樱子总黄酮能保护氧化损伤的HUVEC,其保护机制与提高SOD、CAT、GSH-Px三种抗氧化酶的活性,上调Bcl-2蛋白的表达、下调Bax蛋白的表达来抑制细胞凋亡有关。

Objective To investigate the protective effects and mechanisms of Rosa laevigata Michx total flavonoids（RLMTF） on human umbilical vascular endothelial cells（HUVEC） following oxidative damage. MethodsTo construct the oxidative injury model,Hydrogen Peroxide（H2O2） with different concentrations were used to treat HUVEC.The cell vitality was measured by MTT.SOD,CAT,GSH-Px activities in HUVEC were assayed using microplate spectrophotemeter.Western blotting was employed to detect the expression of the anti-apoptosis protein Bcl-2 and the pro-apoptosis protein Bax in HUVEC. ResultsThe optimal H2O2 concentration to establish oxidative injury model was 600μmol/L.The cell vitalities in different RLMTF concentration groups were obviously raised than those of H2O2 groups（P＆lt;0.01）.Compared with H2O2 oxidative injury group,the activities of SOD in 0.24 mg/ml and 0.48 mg/ml RLMTF groups were obviously increased（P＆lt;0.01）.The activities of CAT and GSH-Px in all RLMTF groups were significantly higher than those of H2O2 oxidative injury group（P＆lt;0.05 or P＆lt;0.01）.The expression levels of Bcl-2 in 0.24 mg/ml RLMTF group and 0.48 mg/ml RLMTF group except 0.12 mg/ml RLMTF group were significantly higher than those of H2O2 oxidative injury groups（P＆lt;0.05）,and the expression levels of Bax in all RLMTF groups were significantly lower than those of H2O2 oxidative injury groups（P＆lt;0.05 or P＆lt;0.01）. ConclusionRLMTF can protect HUVEC from oxidative injury induced by H2O2.The mechanisms were concerned with increasing the activities of SOD,CAT,GSH-Px,up-regulating the expression of Bcl-2 and down-regulating the level of Bax.