Mechanism of enhancing vitamin E activity by sesame seed or its lignans

通过三个实验研究了芝麻及其木脂素增强维生素E活性的机制。在实验1中，我们检测了饲喂对照日粮和含20%芝麻日粮的大鼠肝脏中α -生育酚转移蛋白（α -生育酚转移蛋白）的浓度。使用东京大学药学系Arai博士捐赠的免疫抗体，采用免疫抗体法测定浓度。结果显示，对照组大鼠和芝麻饲料大鼠的α - attp浓度无差异。实验2研究了芝麻木脂素（芝麻素和芝麻氨基酚）对0.5% DHA喂养大鼠脂质过氧化物的抑制作用。在喂食DHA的大鼠中，血浆、肝脏和大脑中的过氧化脂质水平显著增加，血浆和肝脏中的α -生育酚水平下降，但大脑中没有。芝麻素和芝麻胺的添加显著抑制了过氧化脂的产生，并提高了血浆、肝脏和大脑中α -生育酚的水平。这些效果与芝麻素或芝麻醇几乎相同。在实验3中，将只含g-生育酚的芝麻喂给大鼠脑内的γ -生育酚浓度与γ -生育酚喂给大鼠脑内的γ -生育酚浓度进行比较。在芝麻喂养组中发现了高的γ -生育酚浓度，但在γ -生育酚喂养组中发现的γ -生育酚含量可以忽略不计。此外，饲喂了α -生育酚的大鼠大脑中α -生育酚的浓度高于未饲喂芝麻的对照组。

Mechanisms enhancing vitamin E activity by sesame seed or its lignans were investigated in three experiments.In experiment 1 we examined the concentration of the liver alpha-tocopherol transfer protein (alphaTTP) in the liver of rats fed a control diet or a 20% sesame seed containing diet. The concentration was evaluated by the immuno-antibody method using immuno-antibodies kindly donated by Dr. Arai (Dept. of Pharmacology, Tokyo University). The results showed no difference in the concentrations of alphaTTP between control rats and sesame seed fed rats.In experiment 2 we investigated the suppressing effect of sesame lignans (sesamin and sesaminol) on lipid peroxides produced by 0.5 % DHA feeding in rats. In rats fed DHA, lipid peroxide levels significantly increased in the plasma, liver and brain, and alpha-tocopherol levels decreased in the plasma and liver but not the brain. The addition of sesamin and sesaminol significantly inhibited production of lipidperoxide and raised alpha-tocopherol levels in the plasma, liver and brain. These effects were nearly the same with either sesamin or sesaminol.In experiment 3, gamma-tocopherol concentration in the brain of rats fed sesame seed, which contains only g-tocopherol, was compared to that of rats fed gamma-tocopherol. A high gamma-tocopherol concentration was found in tha sesame seed fed group, but negligible amounts of gamma-tocopherol in brain were found in the gamma-tocopherol-fed group. Further, the concentration of alpha-tocopherol in the brain of rats fed sesame seed with alpha-tocopherol was higher than that of control group without sesame seed.