维生素E、C和β-胡萝卜素对老年人细胞氧化损伤影响的研究

目的:探讨不同剂量天然抗氧化β-胡萝卜素(β-C)联合维生素E(VE)和维生素C(VC)干预,对老年机体淋巴细胞增殖活性、红细胞溶血度、红细胞膜流动性和尿中DNA烷化损伤代谢产物O6-甲基鸟嘌呤(O6-MeG)的影响。方法:选择300名60～75岁老年人,经知情后同意参加,随机分为5组:1组至3组每天补充VE 200mg+VC 300mg的同时再分别补充16.7mg、8.4mg和5.6mg天然β-C,4组(VE 200mg/d+VC 300mg/d);5组(对照组)VE 5mg/d;饭后1次口服,连服16w。6补充前后分别用四甲基偶氮唑盐(MTT)法测淋巴细胞增殖活性;H2O2诱导溶血法测红细胞溶血度;荧光偏振法测红细胞膜流动性;高效毛细管电泳法测O6-MeG。结果:干预后1组至4组淋巴细胞增殖活性增高,显著高于其干预前,也明显高于干预后第5组,且干预后第1组显著高于第4组;干预后1组至4组红细胞溶血度均显著低于其干预前,也明显低于干预后第5组;干预后1组至4组红细胞膜荧光偏振度ρ值和微粘度η值均明显低于干预前;干预后1组至4组O6-MeG浓度低于其干预前,也低于干预后第5组。结论:天然抗氧化β-C联合VE、VC干预可提高老年机体淋巴细胞增殖活性,改善红细胞功能,降低DNA的烷化损伤,提高老年机体细胞的抗氧化功能。

EFFECT OF VITAMIN E,C AND β-CAROTENE SUPPLEMENT ON CELLULAR OXIDATIVE DAMAGE IN AGED PEOPLE

Objective:To study the effect of natural antioxidant β-carotene(β-C) combined with vitamin E and C supplement on cellular oxidative damage in aged people. Method:Three hundred subjects aged from 60 to 75y,128 males and 172 females were randomized into 5 groups:group 1(VE 200mg/d+VC 300 mg/d+β-C 16.7 mg/d) ,group 2(VE 200 mg/d+VC 300 mg/d+β-C 8.4 mg/d) ,group 3(VE 200 mg/d+VC 300 mg/d+β-C 5.6 mg/d) ,group 4(VE 200mg/d+VC 300mg/d) ,group 5(VE 5 mg/d) . The trial lasted 16 weeks. All subjects were asked to record the nutrients intake daily. The investigators followed-up and supervised the subjects irregularly. The samples of blood and urine were collected at the beginning and end of the trial. The proliferation of lymphocytes was detected by MTT and H2O2-induced erythrocyte hemolytic degrees were measured before and after the trial. Thefluidity of erythrocyte membrane was evaluated by fluorescence polarization(ρ) and microviscosity(η) . O6-MeG was analyzed by high performance capillary zone electrophoresis. Results:The proliferation of lymphocytes was increased and H2O2-induced erythrocyte hemolytic degrees were decreased from group 1 to group 4 at the end of trial with significant difference compared with control group 5. The ρ and η values were lower in 1 to 4 groups at the end of trial. O6-MeG was significantly lower in group 1 to 4 group at the end of trial,and group 1 lower than group 4. Conclusion:Different doses of natural antioxidant β-carotene supplement combined with vitamin E and C could improve the function of erythrocyte and the proliferation of lymphocytes,and decrease DNA alkylating damage.