Chan A C, Raynor C, Douglas C, Patrick J, Boland M
Am J Clin Nutr. 1986 Aug;44(2):278-82. doi: 10.1093/ajcn/44.2.278.
Human platelet lipooxygenase converts arachidonic acid to 12-hydroperoxy-eicosatetraenoic acid (12-HPETE), which is rapidly reduced by peroxidases to 12-hydroxy-eicosatetraenoic acid (12-HETE). This study was conducted to examine the effect of vitamin E supplementation on platelet 12-lipooxygenase activity. Sixteen healthy subjects were supplemented with 400 IU/day of either D-alpha-tocopherol (268 mg) or DL-alpha-tocopherol (364 mg) for 4 wk. Supplements elicited a transitory increase of lipooxygenase activity but a suppression of peroxidase activity, as indicated by increased 12-HETE production and 12-HPETE accumulation. Plasma-tocopherol concentration was double the presupplement value and remained stable during supplementation. Neither age, sex, nor isomeric form of tocopherol supplement significantly influenced the pattern of response. Results show that vitamin E exerts a differential effect on platelet lipooxygenase and peroxidase activities.
人血小板脂氧合酶可将花生四烯酸转化为12-氢过氧二十碳四烯酸（12-HPETE），后者可被过氧化物酶迅速还原为12-羟基二十碳四烯酸（12-HETE）。本研究旨在探讨补充维生素E对血小板12-脂氧合酶活性的影响。16名健康受试者连续4周每天补充400 IU的D-α-生育酚（268 mg）或DL-α-生育酚（364 mg）。补充剂引起脂氧合酶活性短暂增加，但过氧化物酶活性受到抑制，这表现为12-HETE生成增加和12-HPETE积累。血浆生育酚浓度是补充前值的两倍，且在补充期间保持稳定。年龄、性别以及生育酚补充剂的异构体形式均未显著影响反应模式。结果表明，维生素E对血小板脂氧合酶和过氧化物酶活性具有不同的作用。
