Traber M G, Goldberg I, Davidson E, Lagmay N, Kayden H J
Department of Medicine, New York University School of Medicine, New York.
Gastroenterology. 1990 Jan;98(1):96-103. doi: 10.1016/0016-5085(90)91296-i.
Vitamin E uptake by Caco-2 cells, a human intestinal cell line, was studied by incubating the cells with alpha-tocopherol/triglyceride emulsions with or without bile activated lipase or lipoprotein lipase. During a 1-h incubation, vitamin E was transferred to Caco-2 cells only in the presence of triglyceride hydrolysis by bile activated lipase and not by lipoprotein lipase. Incubation with either lipase resulted in hydrolysis of approximately 20% of the medium [3H]-triolein to free fatty acids and a 3-5-fold increase in cellular radioactivity. In the absence of lipases but the presence of taurocholate, addition of oleic acid in an amount equal to the molar concentration of triglyceride (5.7 mM) to triglyceride emulsions containing either alpha-tocopherol or cholesteryl ester resulted in an increase in cellular [3H]-triglyceride and alpha-tocopherol or cholesteryl ester. We suggest that the absorption of hydrophobic molecules such as vitamin E may occur in the presence of bile and amphipathic lipids via the uptake of micellar neutral lipids by the intestine.
通过将人肠道细胞系Caco - 2细胞与含有或不含有胆汁激活脂肪酶或脂蛋白脂肪酶的α-生育酚/甘油三酯乳液孵育，研究了Caco - 2细胞对维生素E的摄取。在1小时的孵育过程中，维生素E仅在胆汁激活脂肪酶水解甘油三酯的情况下才转移到Caco - 2细胞中，而脂蛋白脂肪酶则不能。用任何一种脂肪酶孵育都会使培养基中约20%的[3H]-三油酸甘油酯水解为游离脂肪酸，并使细胞放射性增加3 - 5倍。在没有脂肪酶但存在牛磺胆酸盐的情况下，向含有α-生育酚或胆固醇酯的甘油三酯乳液中添加摩尔浓度与甘油三酯相等（5.7 mM）的油酸，会导致细胞内[3H]-甘油三酯以及α-生育酚或胆固醇酯增加。我们认为，疏水分子如维生素E的吸收可能在胆汁和两亲性脂质存在的情况下，通过肠道摄取胶束中性脂质而发生。
