[The effect of vitamin C in oxidative modification of low-density lipoprotein induced by macrophage and copperion].
OBJECTIVE
To study the effect of vitamin C on preventing oxidative modification of low density lipoprotein cholesterol (LDL) in vitro.


METHODS
Different levels of vitamin C were added to two different systems of lipid peroxidation of LDL induced by either Cu(2+) or macrophage. The level of VC in systems induced by Cu(2+) were 10, 50, 100 and 200 micromol/L respectively and by macrophage were 50, 100, 200 micromol/L respectively. Vitamin E (200 micromol/L) and VC(0) (0 micromol/L) were served as positive and negative control respectively. The content of TBARS, Ox-LDL, fluorescent compounds, electrophoretic mobility of LDL and the lag-phage of oxidation of LDL were measured.


RESULTS
In the oxidative systems induced by Cu(2+), the groups with higher levels of VC (100, 200 micromol/L) reduced the levels of TBARS, Ox-LDL at 3, 6, and 9 hour after adding Cu(2+), but low dose groups (10, 50 micromol/L) had no the effects. In the macrophage systems, higher levels of VC (100, 200 micromol/L) significantly reduced levels of fluorescent compounds and TBARS, and also lowered electrophoretic mobility of LDL and increased the lag-phage of oxidation of LDL.


CONCLUSIONS
Vitamin C has dual effect on oxidation of LDL. Low dose treatment enhanced oxidation of LDL, but high doses has anti-oxidative effects on LDL.
Chen
Yanqiu
Y
Department of Otorhinolaryngology, First Clinical Hospital of Shanxi Medical University, Taiyuan 030001, China.
Yang
Qi
Q
Yang
Yan
Y
Zhang
Xizhong
X
D000818:Animals; D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000378:metabolism* / Q000494:pharmacology; D002478:Cells, Cultured; D003300:Copper; D004587:Electrophoresis, Agar Gel / Q000379:methods; D005456:Fluorescent Dyes; D008062:Lipofuscin / Q000032:analysis; D008077:Lipoproteins, LDL / Q000096:biosynthesis / Q000378:metabolism*; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D000975:Antioxidants; D005456:Fluorescent Dyes; D008062:Lipofuscin; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; C099252:oxidized low density lipoprotein; D003300:Copper; D001205:Ascorbic Acid