LIPOPROTEIN COMPOSITION INFLUENCES CHOLESTERYL ESTER TRANSFER IN ALCOHOL ABUSERS

Alcohol use is known to increase high-density lipoprotein (HDL) choles terol, which is at least in part mediated by the alcohol-induced reduc tion in plasma cholesteryl ester transfer protein (CETP) activity and mass. We have shown that the high plasma HDL concentration reduces the CETP-mediated net mass transfer of cholesteryl esters from HDL to ver y-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL), or even reverses the direction of transfer in plasma incubations. Theref ore, we studied the effect of lipoprotein composition on lipid net mas s transfers in 14 male alcohol abusers and nine male control subjects by incubating plasma for up to 2 h. The cholesteryl ester net mass tra nsfer in the alcohol abusers was mainly predicted by the VLDL and LDL lipid composition in multiple linear regression, while the HDL composi tion was the main factor in the controls. The observed difference in t he effect of the lipoprotein composition on cholesteryl ester net mass transfer support our previous finding in rabbits that CETP binding to lipoproteins may differ during ethanol oxidation. The results suggest that ethanol oxidation induces alterations which may affect the bindi ng of CETP to lipoproteins.