Both HDL3 and HDL2 exert a powerful anti-oxidative and protective effect against acceleration of oxidative modification of LDL by ascorbic acid.
The objective of the present study was to establish whether high-density lipoprotein 3 (HDL3) or high-density lipoprotein 2 (HDL2) might show an anti-oxidative effect on the acceleration of the oxidative modification of low-density lipoprotein (LDL) by ascorbic acid from measurement of the agarose gel electrophoretic mobility of LDL. LDL was incubated without adding transitional-metal ions for 48 or 96 h in phosphate-buffered saline (PBS) alone, with ascorbic acid (20 microg/mL), or with both ascorbic acid (20 microg/mL) and HDL3 (200 microg protein/mL). The LDL autoxidation occurred in PBS alone. Although ascorbic acid significantly suppressed oxidative modification of LDL after incubation for 48 h, the opposite was true after 96 h. However, since the anti-oxidative ability of HDL2 shows a weaker tendency than that of HDL3, both HDL3 and HDL2 significantly inhibited this acceleration of oxidative modification of LDL by ascorbic acid as assessed by electrophoretic mobility. If there is an augmented oxidative modification of LDL due to ascorbic acid in vivo, HDL3 or HDL2 may thus have an important role in inhibiting this ascorbic acid-accelerated oxidation of LDL.
Sakuma
Nagahiko
N
Department of Internal Medicine and Pathophysiology, Nagoya City University Graduate School of Medical Sciences, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan.
Saeki
Tomoaki
T
Yajima
Kazuhiro
K
Hibino
Takeshi
T
Yoshida
Takayuki
T
Mizuno
Hiromi
H
Mukai
Seiji
S
Sakata
Seiichiro
S
Kunimatsu
Mitoshi
M
Kimura
Genjiro
G
D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D004587:Electrophoresis, Agar Gel; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008075:Lipoproteins, HDL / Q000494:pharmacology*; D053439:Lipoproteins, HDL2; D053440:Lipoproteins, HDL3; D008077:Lipoproteins, LDL / Q000032:analysis / Q000737:chemistry*; D010084:Oxidation-Reduction; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
D000975:Antioxidants; D008075:Lipoproteins, HDL; D053439:Lipoproteins, HDL2; D053440:Lipoproteins, HDL3; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; C099252:oxidized low density lipoprotein; D001205:Ascorbic Acid