铜介导的低密度脂蛋白氧化程度取决于氧化时间和铜/低密度脂蛋白比例：化学特征分析。

Extent of copper LDL oxidation depends on oxidation time and copper/LDL ratio: chemical characterization.

作者信息

Zarev Stéphanie, Bonnefont-Rousselot Dominique, Jedidi Iness, Cosson Claudine, Couturier Martine, Legrand Alain, Beaudeux Jean-Louis, Thérond Patrice

机构信息

Laboratoire de Biochimie Métabolique et Clinique, Faculté de Pharmacie, 4, avenue de l'Observatoire, 75270 Paris Cedex 06, France.

出版信息

Arch Biochem Biophys. 2003 Dec 1;420(1):68-78. doi: 10.1016/j.abb.2003.09.022.

DOI:10.1016/j.abb.2003.09.022

PMID:14622976

Abstract

The aim of our study was to determine, as a function of [Cu(2+)]/[LDL] ratios (0.5 and 0.05) and of oxidation phases, the extent of LDL oxidation by assessing the lipid and apo B oxidation products. The main results showed that: (i) kinetics of conjugated diene formation presented four phases for Cu(2+)/LDL ratio of 0.5 and two phases for [Cu(2+)]/[LDL] ratio of 0.05; (ii) oxidation product formation (cholesteryl ester and phosphatidylcholine hydroperoxides, apo B carbonyl groups) occurred early in the presence of endogenous antioxidants, under both copper oxidation conditions; (iii) apo B carbonylated fragments appeared when antioxidants were totally consumed at [Cu(2+)]/[LDL] ratio of 0.5; and (iv) antioxidant concentrations were stable, oxysterol formation was negligible, and no carbonylated fragment was detected at [Cu(2+)]/[LDL] ratio of 0.05. Depending on the copper/LDL ratio, oxidized LDL differ greatly in the nature of lipid peroxidation product and the degree of apo B fragmentation.

摘要

我们研究的目的是根据[Cu(2+)]/[LDL]比率（0.5和0.05）以及氧化阶段，通过评估脂质和载脂蛋白B氧化产物来确定低密度脂蛋白（LDL）氧化的程度。主要结果表明：（i）对于Cu(2+)/LDL比率为0.5时，共轭二烯形成的动力学呈现四个阶段，而对于[Cu(2+)]/[LDL]比率为0.05时呈现两个阶段；（ii）在两种铜氧化条件下，在内源性抗氧化剂存在的情况下，氧化产物（胆固醇酯和磷脂酰胆碱氢过氧化物、载脂蛋白B羰基）早期就会形成；（iii）当抗氧化剂在[Cu(2+)]/[LDL]比率为0.5时完全消耗时，会出现载脂蛋白B羰基化片段；以及（iv）在[Cu(2+)]/[LDL]比率为0.05时，抗氧化剂浓度稳定，氧化甾醇形成可忽略不计，且未检测到羰基化片段。根据铜/LDL比率的不同，氧化型LDL在脂质过氧化产物的性质和载脂蛋白B片段化程度上有很大差异。