Oxidation of low density lipoprotein and plasma by 15‐lipoxygenase and free radicals

FEBS Letters

Nakamura, Akio²  Niki, Etsuo²  Kühn, Hartmut¹  Noguchi, Noriko²  Yamashita, Hiromasa² 

[1] Institute of Biochemistry, University Clinicum Charite, Humboldt University Berlin, Hessische Str. 3-4, D-10115 Berlin, Germany;Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153, Japan

关键词: Lipoxygenase;    Low density lipoprotein;    Lipid peroxidation;    Plasma;    CE;    cholesteryl ester;    CEOH;    cholesteryl ester hydroxide;    CEOOH;    cholesteryl ester hydroperoxide;    EDTA;    ethylenediaminetetraacetic acid;    HPLC;    high pressure liquid chromatography;    HODE;    hydroxyoctadecadienoate;    LDL;    low density lipoprotein;    LOX;    lipoxygenase(s);    MeO-AMVN;    2;    2′-azobis(4-methoxy-2;    4-dimethylvaleronitrile);    PBS;    phosphate buffered saline;    PC;    phosphatidylcholine;    PCOH;    phosphatidylcholine hydroxide;    PCOOH;    phosphatidylcholine hydroperoxide;    TMAH;    tetramethylammonium hydroxide;   

DOI  :  10.1016/S0014-5793(99)00137-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

It is generally accepted that the oxidation of pentadiene structures of polyunsaturated lipids by lipoxygenase (LOX) is regio- and enantio-specific, while the free radical-mediated lipid peroxidation gives stereo-random racemic products. It was confirmed that the oxidation of human low density lipoprotein (LDL) by 15-LOX from rabbit reticulocytes gave phosphatidylcholine (PC) and cholesteryl ester (CE) hydroperoxides regio-, stereo- and enantio-specifically. 15-LOX also oxidized human plasma to give specific PC and CE hydroperoxides in spite of the presence of high concentrations of antioxidants. More CE hydroperoxides were formed than PC hydroperoxides from LDL, but the reverse order was observed for plasma oxidation. The S/R ratio of the hydroperoxides decreased during long time incubation but remained significantly larger than one, while free radical-mediated oxidation of LDL and plasma gave racemic products.

【 授权许可】

Unknown