[Inhibitory effect of Isorhamnetin and Hesperidin on LDL oxidation induced by Cu2+].
OBJECTIVE
To evaluate the inhibitory effect of Isorhamnetin and Hesperidin on the LDL oxidation induced by Cu2+.


METHODS
The serum LDL was isolated by the one step density gradient ultracentrifugation. The LDL oxidation was induced by Cu2+ in vitro for different time periods. Isorhamnetin and Hesperidin at 5 micromol/L were added respectively, as the experimental groups, 3 hours before oxidation. The oxidation of LDL in experimental and control groups was identified by measuring A234 , REM, TBARS and protein carbonyls content.


RESULTS
The values of A234, REM, TBARS and protein carbonyls formation increased gradually during LDL oxidation induced by Cu2+ in vitro. During LDL oxidation induced by Cu2+ in vitro and incubation with each of Isorhamnetin and Hesperidin, the kinetic changes of A234 , REM, TBARS and protein carbonyls formation showed lag phases of 2-4 h and 2 h respectively, and the corresponding values for each of the agents treated group were reduced by 23.5%-40.4%, 20.5%-37.7%, 18.6-30.3% and 20.1%-52.4% (P < 0.001); and 11.1%-21.2%, 9.2%-28.3%, 13.7%-21.3% and 5.0%-43.8% respectively (P < 0.001, P < 0.01, P < 0.001 and P < 0.05).


CONCLUSIONS
It suggests that Isorhamnetin and Hesperidin can substantially inhibit LDL oxidation, and Isorhamnetin has antioxidation ability stronger than Hesperidin.
Liu
Rui
R
Division of Peptides Related with Human Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China. liurui60@hotmail.com
Meng
Fang
F
Liu
Yu
Y
Bai
Huai
H
Liu
Bing-Wen
BW
D000975:Antioxidants / Q000494:pharmacology*; D003300:Copper / Q000737:chemistry / Q000494:pharmacology*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D044948:Flavonols / Q000494:pharmacology*; D006569:Hesperidin / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects; D008077:Lipoproteins, LDL / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D050050:Protein Carbonylation / Q000187:drug effects; D011794:Quercetin / Q000031:analogs & derivatives; D017392:Thiobarbituric Acid Reactive Substances / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors
D000975:Antioxidants; D004365:Drugs, Chinese Herbal; D044948:Flavonols; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; C047368:3-methylquercetin; D003300:Copper; D011794:Quercetin; D006569:Hesperidin