Rifici V A, Khachadurian A K
Department of Medicine, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, New Brunswick.
J Am Coll Nutr. 1993 Dec;12(6):631-7. doi: 10.1080/07315724.1993.10718353.
The oxidative modification of lipoproteins has been implicated in atherogenesis, suggesting a protective role of circulating antioxidants. Vitamin C (ascorbic acid, 1 g/day) and vitamin E (dl alpha-tocopheryl acetate, 800 IU/day) were administered to healthy female and male volunteers. Lipoproteins with density < 1.063 g/mL were isolated from serum before and after vitamin supplementation and incubated with copper (Cu) or mononuclear cells (MC) plus Cu. Administration of vitamins C and E together to 4 subjects for 10 days resulted in a 57% (range 40-72%) decrease in Cu-catalyzed production of thiobarbituric acid reactive substances (TBARS) under the following conditions of assay: incubation times of 0-8 hours, Cu concentrations of 0-10 microM lipoprotein protein concentrations of 0.1-0.5 mg/mL. Decreases in other parameters of lipoprotein oxidation, i.e,, electrophoretic mobility, production of conjugated dienes and modification of amino groups, were also observed. Vitamin E administration alone produced a 52% inhibition and vitamin C alone a 15% inhibition of TBARS formation. Vitamins C and E supplementation resulted in a 78% decrease in the susceptibility of lipoproteins to MC-mediated oxidation. There was a strong inverse correlation (r = -0.64, p < 0.0007) between vitamin E levels in the lipoproteins and TBARS production in samples from 12 subjects administered vitamins C and E. In 3 individuals vitamin E levels remained low and in 2 of these subjects there was no effect of vitamins C and E administration on TBARS production. These results suggest a protective role of antioxidant vitamins and significant individual variability in response.
脂蛋白的氧化修饰与动脉粥样硬化的发生有关，这表明循环抗氧化剂具有保护作用。对健康的女性和男性志愿者给予维生素C（抗坏血酸，每日1克）和维生素E（dl-α生育酚醋酸酯，每日800国际单位）。在补充维生素前后从血清中分离出密度<1.063克/毫升的脂蛋白，并与铜（Cu）或单核细胞（MC）加铜一起孵育。对4名受试者联合给予维生素C和E共10天，在以下检测条件下，铜催化的硫代巴比妥酸反应性物质（TBARS）生成量减少了57%（范围为40%-72%）：孵育时间0 - 8小时、铜浓度0 - 10微摩尔、脂蛋白蛋白浓度0.1 - 0.5毫克/毫升。还观察到脂蛋白氧化的其他参数降低，即电泳迁移率、共轭二烯生成量和氨基修饰。单独给予维生素E产生了52%的抑制作用，单独给予维生素C产生了15%的TBARS生成抑制作用。补充维生素C和E使脂蛋白对MC介导的氧化的敏感性降低了78%。在12名接受维生素C和E的受试者的样本中，脂蛋白中的维生素E水平与TBARS生成量之间存在强烈的负相关（r = -0.64，p < 0.0007）。在3名个体中，维生素E水平仍然较低，其中2名受试者补充维生素C和E对TBARS生成没有影响。这些结果表明抗氧化维生素具有保护作用，且个体反应存在显著差异。
