Peroxidized low-density lipoprotein with four kinds of hydroperoxidized cholesteryl linoleate estimated in plasma of young heavy smokers.

Abstract

To clarify the mechanisms of vascular complications due to heavy smoking, it was studied whether hydroperoxidized low-density lipoprotein (HPO-LDL) was estimated in plasma of young heavy smokers. Plasmas were separated from 15 young male students (HS-M) who smoked more than 30 cigarettes/day over 5 years, and from 10 nonsmoker students (NS-M) too. LDL was isolated by ultracentrifugation. HPO-cholesteryl linoleate (HPO-CL) was identified by thin-layer chromatography (TLC), and lipid peroxide was measured by Determiner LPO (Kyowa Medics Co., Ltd, Tokyo, Japan). The molecular structure of lipid peroxide in LDL was identified using GMS analysis, HPLC chromatography and 1H-NMR analysis. (1) HPO-CL was clearly observed on the TLC in LDL lipids of HS-M but from NS-M it was barely found. (2) Lipid peroxide in LDL separated from HS-M consisted of HPO-CL and reduced HPO-CL. Peroxidized LDL was estimated in plasma with young heavy smokers. Because of injurious reactions in vessels of peroxidized LDL, it is considered that heavy smoking is one of the risk factors for vascular complications in heavy smokers.