Nair P P, Judd J T, Berlin E, Taylor P R, Shami S, Sainz E, Bhagavan H N
Lipid Nutrition Laboratory, Beltsville Human Nutrition Research Center, USDA, MD 20705.
Am J Clin Nutr. 1993 Jul;58(1):98-102. doi: 10.1093/ajcn/58.1.98.
Healthy men (ages 24-57 y) were fed a controlled basal diet supplemented with 15 g/d of placebo oil (PO) for 10 wk followed by 15 g/d of fish-oil concentrate (FO) (fortified with 15 mg all-rac-tocopherol) for 10 wk without additional alpha-tocopherol and the last 8 wk with 200 mg alpha-tocopherol/d (FO+E). Compared with PO, FO raised plasma malondialdehyde; lowered alpha-tocopherol in plasma, red blood cells, and platelets; and raised plasma and platelet beta-carotene. Supplementation with additional alpha-tocopherol (FO+E) not only restored tocopherol concentrations but also reversed the rise in beta-carotene. The response in retinol, particularly in platelets, showed an inverse relationship to beta-carotene, alpha-tocopherol exhibiting a modulating effect on these changes. From these observations it is postulated that platelets may be a significant extraintestinal site of retinol formation from beta-carotene.
健康男性（年龄在24 - 57岁之间）先食用一种添加了15克/天安慰剂油（PO）的受控基础饮食10周，接着食用15克/天的鱼油浓缩物（FO）（添加15毫克全消旋生育酚）10周，期间不额外补充α - 生育酚，最后8周补充200毫克α - 生育酚/天（FO + E）。与PO相比，FO使血浆丙二醛升高；降低了血浆、红细胞和血小板中的α - 生育酚；并提高了血浆和血小板中的β - 胡萝卜素。额外补充α - 生育酚（FO + E）不仅恢复了生育酚浓度，还逆转了β - 胡萝卜素的升高。视黄醇的反应，尤其是在血小板中的反应，与β - 胡萝卜素呈负相关，α - 生育酚对这些变化具有调节作用。基于这些观察结果推测，血小板可能是β - 胡萝卜素形成视黄醇的一个重要肠外部位。
