Antioxidant effects of ginsenoside Re in cardiomyocytes.
We have previously demonstrated that American ginseng berry extract exhibited significant protection against oxidant-mediated injury in cardiomyocytes. To extend this work, we sought to investigate the antioxidant effects of Re, a protopanaxatriols-type and single chemical integrant present in American ginseng berry extract, using the same chick cardiomyocyte model of oxidant injury as well as ESR spectroscopy in a cell-free chemical system. In cells exposed to 2 h of H2O2 (0.5 mM), pretreatment with Re (0.05, 0.1, or 0.5 mg/ml for 2 h) significantly attenuated 2',7'-dichlorofluorescein (DCF) fluorescence by 51% (from 1345+/-67 to 658+/-46 a.u., P<0.001), and remarkably reduced cell death (from 51.5+/-3.0% to 11.8+/-1.5%, P<0.001, compared to the control). Similar results were also observed in cells exposed to antimycin A (100 microM), a mitochondrial electron transport chain site III inhibitor which increases endogenous oxidative stress. In the ESR study, however, Re failed to reduce the formation of the superoxide/DMPO adduct and DPPH radicals. These results suggest that ginsenoside Re functions as an antioxidant, protecting cardiomyocytes from oxidant injury induced by both exogenous and endogenous oxidants, and that its protective effects may be mostly attributed to scavenging H2O2 and hydroxyl radicals.
Xie
Jing-Tian
JT
Tang Center for Herbal Medicine Research, Pritzker School of Medicine, University of Chicago, Chicago, IL 60637, USA.
Shao
Zuo-Hui
ZH
Vanden Hoek
Terry L
TL
Chang
Wei-Tien
WT
Li
Jing
J
Mehendale
Sangeeta
S
Wang
Chong-Zhi
CZ
Hsu
Chin-Wang
CW
Becker
Lance B
LB
Yin
Jun-Jie
JJ
Yuan
Chun-Su
CS
D000818:Animals; D000968:Antimycin A / Q000633:toxicity; D000975:Antioxidants / Q000494:pharmacology*; D002470:Cell Survival; D002642:Chick Embryo; D004578:Electron Spin Resonance Spectroscopy; D036145:Ginsenosides / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000633:toxicity; D023421:Models, Animal; D032383:Myocytes, Cardiac / Q000187:drug effects*; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress; D014475:Uncoupling Agents / Q000633:toxicity
D000975:Antioxidants; D036145:Ginsenosides; D016877:Oxidants; D014475:Uncoupling Agents; C049864:ginsenoside Re; D000968:Antimycin A; D006861:Hydrogen Peroxide