Minimally modified LDL is an oxidized LDL enriched with oxidized phosphatidylcholines.
The oxidative modification of low-density lipoprotein (LDL) is involved in atherogenesis. Among a variety of modified LDLs mentioned in the literature, so-called minimally modified LDL (MM-LDL) was reported to have pro-atherogenic properties despite minimal changes in its oxidative measures. After treatment of LDL with 1 micro M FeSO(4) at 4 degrees C for 96 h, the resulting MM-LDL showed a slight increase in thiobarbituric acid-reactive substances (TBARS) and little association with macrophages. On the other hand, heavily oxidized LDL, which was prepared by copper-induced oxidation of LDL at 37 degrees C, showed a sharp increase in TBARS and strong association with macrophages. By introducing a fluorometric procedure to detect aldehyde-containing phosphatidylcholines (aldehyde-PCs), we examined the amounts of aldehyde-PCs in modified LDL preparations. Aldehyde-PCs increased to 23.4 pmol/ microg protein in MM-LDL, which was more than four-fold higher than in the heavily oxidized LDL. We conclude that MM-LDL is a unique type of oxidized LDL enriched with aldehyde-PCs.
Itabe
Hiroyuki
H
Department of Molecular Pathology, Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1 Suarashi, Sagamiko, Tsukui, Kanagawa 199-0195. h-itabe@pharm.teikyo-u.ac.jp
Mori
Masahiro
M
Fujimoto
Yasuyuki
Y
Higashi
Yusuke
Y
Takano
Tatsuya
T
D000447:Aldehydes / Q000378:metabolism; D003956:Dialysis; D005470:Fluorometry / Q000379:methods; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood / Q000378:metabolism*; D010084:Oxidation-Reduction; D010713:Phosphatidylcholines / Q000378:metabolism*; D013696:Temperature; D017392:Thiobarbituric Acid Reactive Substances / Q000494:pharmacology
D000447:Aldehydes; D008077:Lipoproteins, LDL; D010713:Phosphatidylcholines; D017392:Thiobarbituric Acid Reactive Substances; C099252:oxidized low density lipoprotein