黄芪多糖对过氧化氢诱导的内皮细胞损伤的保护作用

Protective effects of Astragalus polysaccharide on endothelial cell injury induced by hydrogen peroxide.

目的:观察黄芪多糖(Astragalus polysaccharide,APS)对过氧化氢(H2O2)诱导的人脐静脉内皮细胞HUVECs损伤的保护作用及其可能的作用机制。方法:不同浓度的黄芪多糖孵育内皮细胞1h后加入400μmol/L的H2O2继续培养24h,用MTT法检测细胞活性;DAPI/PI双染法观察细胞形态并统计细胞凋亡率;硝酸还原酶法测定NO释放量;Western blot法测定Cu/Zn-SOD蛋白表达。结果:H2O2模型组细胞活性较之空白对照组下降42.87%,细胞核皱缩形态不规则化,细胞凋亡率升高了7倍、NO释放量降低42.96%,Cu/Zn-SOD蛋白表达下降45.31%;与模型组相比黄芪多糖各剂量组可不同程度改善这些变化,其中黄芪多糖1μg/ml组作用最为明显,其细胞活性和NO释放量分别增加24.96%、32.13%,细胞凋亡率降低36.02%,Cu/Zn-SOD蛋白表达升高37.14%。结论:黄芪多糖可能通过影响内皮细胞NO释放量和Cu/Zn-SOD蛋白表达,改善细胞NO与氧自由基的平衡发挥保护作用。

Objective： To observe the protective effect of Astragalus polysaccharides（ APS） against human umbilical vein endothelial cells（ HUVECs） damage induced by hydrogen peroxide（ H2O2） and its possible mechanism. Methods： The HUVECs were preincubated with different concentrations of APS for 1h and subsequently stimulted with 400μmol / L H2O2 for 24h. The cell viability was detected by MTT assay; DAPI /PI double staining were used to evaluate nuclei morphology and apoptosis rate; NO levels was determinated by nitrate reductase method; the expression of Cu / Zn-SOD were assessed by Western blot. Results： Compared with the control group,in H2O2 model group,the cell viability were decreased by 42. 87% with shrunken,irregular,and fragmented nuclei,the cell apoptosis rate were increased by 7 times,the levels of NO were decreased by 42. 96%,the protein expression of Cu / Zn-SOD were reduced by 45. 31%. Compared with the model group,all these changes were improved in different Astragalus polysaccharide groups,the effect of Astragalus polysaccharide group（ 1μg / ml） were the most obvious while the cell viability and the release of NO were increased by 24. 96%,32. 13% respectively,the apoptosis rate were decreased by36. 02%,Cu / Zn-SOD protein expression were increased by 37. 14%. Conclusions： APS may through increasing the release of NO and Cu /Zn-SOD protein expression,improving the balance between NO levels and oxygen free radicals play a protective role.