Abstract
We have reported that high exogenous vitamin E (0.1-1 mM) inhibits thioglycollate-induced mouse peritoneal macrophages from binding and uptake of oxidized low density lipoprotein (oxLDL). However, in the present study, we found the amount of oxLDL bound to mouse macrophages increased with increasing levels of endogenous vitamin E in macrophages. Different vitamin E levels in macrophages were obtained by feeding mice with vitamin E deficient-, adequate- or rich-diet for 3 weeks;0.02, 0.12 and 0.14 μg/mg protein, respectively. Exogenous vitamin E dose-dependently (up to 1 μM) increased the amount of oxLDL bound to macrophages from mice fed vitamin E adequate-diet and the numbers of lipid droplet positive macrophages. An increase of oxLDL binding with increasing of exogenous vitamin E was also observed in macrophages from mice fed vitamin E deficient-diet. Above results suggest that vitamin E at physiological levels enhances macrophages to bind and incorporate oxLDL.
