补充叶黄素及EGCG对人体抗氧化活性及DNA氧化损伤的影响

Effects of lutein and EGCG supplementation on antioxidative activity and DNA oxidative damage

目的:探讨补充叶黄素与表没食子儿茶素没食子酸酯(EGCG)对机体抗氧化活性及DNA氧化损伤的影响。方法:选择40名健康青年志愿者,随机分为4组,分别为叶黄素组(20 mg/d)、EGCG组(270 mg/d)、叶黄素(20 mg/d)+EGCG(270 mg/d)组和正常对照组。3个实验组志愿者连续补充叶黄素和/或EGCG 20 d,正常对照组未给任何补充。试验前及试验第21天分别留取受试者清晨空腹静脉血5 m L,分离血浆并收集淋巴细胞。高效液相色谱法检测血浆中叶黄素和EGCG浓度,测定总超氧化物歧化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量,采用碱性单细胞凝胶电泳法测定外周血淋巴细胞DNA损伤状况。结果:经过20 d后,叶黄素组和叶黄素+EGCG组受试者血浆中叶黄素水平较干预前分别升高了257%和175%(P<0.01)。与正常对照组相比,干预后叶黄素组受试者血浆中MDA含量、T-SOD活力明显下降、GSH-Px活力显著升高(P均<0.05),EGCG组受试者血浆中MDA含量、T-SOD、GSH-Px活力无明显差异(P均>0.05),叶黄素和EGCG对机体抗氧化活力无交互作用。DNA损伤分析显示,叶黄素组、EGCG组中由低、中浓度H2 O2诱导的外周血淋巴细胞DNA损伤均显著低于对照组(P<0.05),而由高浓度H2 O2诱导的DNA氧化损伤及自发损伤与对照组比较差异无统计学意义,叶黄素和EGCG对DNA损伤的影响无交互作用(P均>0.05)。结论:叶黄素、EGCG单独补充均可降低一定浓度H 2O 2诱导的DNA氧化损伤,叶黄素单独补充也可增强机体抗氧化活性;叶黄素与EGCG对机体抗氧化活性及DNA氧化损伤的影响均无交互作用。

OBJECTIVE： To investigate the effects of lutein and epigallocatechin gallate（EGCG） supplementation on the antioxidant activity and DNA damage. METHODS：A total of 40 healthy young adults were randomly divided into four groups（n=10 in each group）,including lutein group（20 mg/d）,EGCG group（270 mg/d）,lutein（20 mg/d）＋EGCG（270 mg/d） group and normal control group. Three experimental groups of volunteers were treated with lutein and or EGCG for 20 d while the control group wasn＇t given any supplement. 5 m L fasting blood was collected at the beginning and the end of the trial. Plasma lutein and EGCG concentrations were measured by HPLC detector systems. Plasma total superoxide dismutase（T-SOD）,glutathione peroxidase（GSH-Px） and malondial dehyde（MDA） levels were measured by kits. Peripheral blood lymphocyte DNA damage was analyzed by single-cell gel electrophoresis（SCGE）. RESULTS：After supplementation for 20 days,plasma lutein concentration of the subjects in the lutein group and lutein＋EGCG group increased by 257% and 175%（P0.01）. Plasma MDA and T-SOD concentrations of the subjects in the lutein group were significantly lower than those of the control group,while plasma GSH-Px concentration was significantly increased（P0.05）. No significant difference was found in the antioxidant activity of the subjects in the EGCG group. The combined supplementation of lutein and EGCG had no interaction on the antioxidant activity. DNA damage analysis showed that low- and medium- concentration H O-induced DNA damage were markedly lower in either lutein or EGCG group than those in 2 2the control group（P0.05）. However high- concentration H O-induced and spontaneous DNA damage in both groups did 2 2not show any significant difference with those in the control group. The combined supplementation of lutein and EGCG had no interaction on the DNA damage（P0.05）. CONCLUSION：Lutein or EGCG supplementation alone could effectively reduce DNA damage. Lutein supplementation enhanced antioxidant activity,but EGCG did not. Lutein and EGCG did not show any interaction on antioxidant activity and DNA damage.