Identification and quantification of regioisomeric cholesteryl linoleate hydroperoxides in oxidized human low density lipoprotein and high density lipoprotein.

Published

Journal Article

Oxidation of human LDL is implicated as an initiator of atherosclerosis. Isolated low density lipoprotein (LDL) and high density lipoprotein (HDL2) were exposed to aqueous radicals generated from the thermolabile azo compound 2,2'-azobis(2-amidinopropane) dihydrochloride. The primary nonpolar lipid products formed from the autoxidation of LDL and HDL were the regioisomeric cholesteryl linoleate hydroperoxides. In LDL oxidations, 9- and 13-hydroperoxides with trans,cis conjugated diene were formed as the major oxidation products if endogenous alpha-tocopheral was present in the LDL. After extended oxidation of LDL, at the time when endogenous alpha-tocopherol was consumed, the two trans,cis conjugated diene hydroperoxides began to disappear and the 9- and 13-hydroperoxides with trans,trans conjugated diene appeared. At very long oxidation times, none of the primary products, the conjugated diene hydroperoxides, were present. In HDL2, which has only very low levels of antioxidants, both the 9- and 13-hydroperoxides with trans,cis conjugated diene and the 9- and 13-hydroperoxides with trans,trans conjugated diene were formed at early stages of oxidation. The corresponding alcohols were also formed in the HDL2 oxidations. A mechanistic hypothesis consistent with these observations is presented.

Full Text

Duke Authors

Cited Authors

  • Kenar, JA; Havrilla, CM; Porter, NA; Guyton, JR; Brown, SA; Klemp, KF; Selinger, E

Published Date

  • June 1996

Published In

Volume / Issue

  • 9 / 4

Start / End Page

  • 737 - 744

PubMed ID

  • 8831818

Pubmed Central ID

  • 8831818

Electronic International Standard Serial Number (EISSN)

  • 1520-5010

International Standard Serial Number (ISSN)

  • 0893-228X

Digital Object Identifier (DOI)

  • 10.1021/tx9600098

Language

  • eng