中文摘要：

目的探讨齐墩果酸对氧化性低密度脂蛋白（oxLDL）诱导人脐静脉内皮细胞（HUVEC）损伤的保护作用。方法体外培养HUVEC,以维生素E（200μmol/L）或齐墩果酸（5-40μmol/L）预处理细胞24h,再加入200mg/L oxLDL继续培养24h造成细胞损伤。采用MTT法检测各组细胞存活率,同时检测细胞丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性、还原型谷胱甘肽（GSH）含量,采用DCFH-DA探针法检测细胞内活性氧（ROS）含量。结果与正常组比较,200mg/L oxLDL组细胞存活率、SOD活性、GSH含量明显降低,MDA、ROS含量明显增加,差异均有统计学意义（F=67.72-173.25,q=11.46-30.86,P〈0.01）;与200mg/L oxLDL组比较,齐墩果酸在5-20μmol/L浓度范围内,可剂量依赖性提高细胞存活率、减少MDA含量及ROS形成、增加GSH含量及SOD活性（q=4.26-22.35,P〈0.05）。结论齐墩果酸能抑制ox-LDL诱导的HUVEC氧化损伤,其机制可能与维持SOD活性,减少ROS释放、MDA生成及GSH消耗有关。

英文摘要：

Objective To investigate the protective effect of oleanolic acid on damaged umbilical vein endothelial cells（HUVECs）induced by oxLDL. Methods Methods HUVECs were in vitro cultured and pretreated with vitamin E（200μmol/L）or oleanolic acid（5-40μmol/L）for 24 h,and then again added 200mg/L oxLDL to continuously cultivate for 24 hto cause cell damage.Employing MTT,the survival rate of HUVECs,cell content of malondialdehyde（MDA）,the activity of superoxide dismutase（SOD）and content of glutathione（GSH）were detected,and using DCFH-DA to measure the content of intracellular reactive oxygen species（ROS）. Results Compared with the normal control group,the cell survival rate in the oxLDL group decreased,the contents of GSH and SOD declined,and that of ROS and MDA increased,the differences were significant（F=67.72-173.25,q=11.46-30.86,P 〈0.01）.Compared with the oxLDL group,5-20μmol/L oleanolic acid groups significantly increased the cell survival rate,decreased the levels of ROS and MDA,and increased GSH content and SOD activity in a concentration-dependent manner（q=4.26-22.35,P〈0.05）. Conclusion Oleanolic acid can prevent HUVECs from oxidative injury induced by oxLDL and its role may be related to the maintenance of SOD activity,reduction of ROS release,of MDA production and decrease of GSH consumption.