[The difference in cholesterol metabolism by tocopheryl linolate and a mixture of tocopherol and linoleic acid with special reference to biosynthesis, absorption and excretion (author's transl)]

Animal experiments using mice were conducted to determine the difference of cholesterol metabolism, if any, between a group of mice administered with dl-alpha-tocopheryl linolate (EL) and another group administered with a mixture of dl-alpha-tocopheryl acetate (E), and ethyllinolate (L) (E+L) that were combined in such a way as to have the same composition as EL. The following results were obtained. 1. While no difference in cholesterol biosynthesis was seen in, in vitro liver homogenate to which agent were added, in liver from animals orally administered with agents in vivo, a decrease in biosynthesis of liver cholesterol in the EL group compared against the E+L group was seen, where-as opposite results were obtained when the agents were injected. 2. Absorption of cholesterol was studied. Cholesterol-4-14C was intubated into the stomach of mice fed with the agents. From the cholesterol radioactivity appearing in blood, it was seen that the inhibition of cholesterol absorption in the small intestine was higher in the EL group than in the E+L group. At the same time the excretion of the sterol-14C coming from the intubated cholesterol-14C into the feces was considerably higher in the EL group as compared with the E+L group. However, when a mixture of the agents and cholesterol-4-14C was intubated into the stomach of normally fed mice, no differences in absorption was seen and results opposite to the above were seen in the excretion of sterol-14C into the feces. 3. Following cholesterol-4-14C injection, when the mice were fed on agent added feed, the EL group showed an increased excretion of sterol-14C and sterol into feces as compared with the E+L group. 4. Regarding the disappearance of injected cholesterol-4-14C from the tissue, no difference was seen between the EL group and the E+L group, when the agents were injected or fed. 5. With regard to in vivo biosynthesis of fatty acid in the group administered orally with the agents, liver fatty acid biosynthesis showed to decrease in the EL group compared with the E+L group, while opposite results were seen in the injected groups. Based on the above, when viewed from cholesterol metabolism, oral administration of agents in the EL group showed a superior effect as a cholesterol-lowering agents compared against the E+L group and the writer is of the opinion that this may well be used for clinical purposes.