Effects of postprandial hyperlipemia on the vitamin E content of lipoproteins

Delayed postprandial clearance of triglyceride-rich lipoproteins (TGRL) could induce a decrease of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) vitamin E content through its transfer into TGRL. We thus studied lipoprotein vitamin E content during postprandial hypertriglyceridemia induced by a high fat meal without vitamin E supplement. Venous blood was drawn from five healthy male volunteers following a 12 h fast at (t(0)) then 2 h (t(2)), 4 h (t(4)), 6 h (t(6)) and 8 h (t(8)) after a 80 g fat meal. In plasma, only TG significantly varied during the postprandial period with a large interindividual variability. Mean composition of lipoproteins in terms of mass was not significantly modified. The amount of vitamin E significantly increased in TGRL and decreased in LDL plus HDL at t(4) and t(6) relative to t(0). Vitamin E content of TGRL and LDL but not of HDL decreased significantly at t(4). The mean decrease was 20% (range 5%-54%) for the LDL. LDL- and HDL vitamin E content correlated inversely with plasma TGRL levels. Our data suggest that LDL from subjects with delayed chylomicron clearance could be less protected against oxidation. (C) 1998 Elsevier Science B.V. All rights reserved.