Vitamin E reduces cholesterol esterification and uptake of acetylated low density lipoprotein in macrophages

The effects of vitamin E on cholesteryl ester (CE) metabolism in J774 cells were examined. Pretreatment of J774 cells with vitamin E at concentrations above 50 mu M significantly decreased acetylated low density lipoprotein ( LDL)-induced incorporation of [C-14]oleate into CE in cells in a dose-depen dent manner. This was partly due to vitamin E also significantly inhibiting the uptake of [H-3]CE-labeled acetylated LDL by J774 cells. A trend existe d toward suppression of acyl-CoA:cholesterol acyltransferase (ACAT) activit y in the cell lysate at high vitamin E concentration, but there was no effe ct on hydrolysis of CE. These data indicate that vitamin E reduces the upta ke of modified LDL and suppresses ACAT activity, resulting in less choleste rol esterification in macrophages: a novel mechanism underlying the antiath erogenic properties of vitamin E.