title: EPR studies on the superoxide-scavenging capacity of the nutraceutical resveratrol.
abstract: Resveratrol (3,4',5-trihydroxystilbene), a polyphenolic compound found in mulberries, grapes, and red wine, has received considerable attention because of its apparent protective effects against various degenerative diseases due to its potential antioxidant activities. However, direct evidence for the superoxide-scavenging capacity of resveratrol is lacking in literature. In this study, electron paramagnetic resonance spectroscopy in combination with 5-(diethoxyphosphoryl)-5-methylpyrroline-N-oxide (DEPMPO)-spin trapping technique was utilized to determine the ability of resveratrol in scavenging superoxide anions generated from both potassium superoxide and the xanthine oxidase/xanthine system. We have demonstrated here for the first time that the presence of resveratrol resulted in decreased formation of DEPMPO-superoxide adduct (DEPMPO-OOH) in both the potassium superoxide and xanthine oxidase/xanthine systems, indicating that resveratrol could directly scavenge superoxide anions. The inhibition of DEPMPO-OOH in the xanthine oxidase/xanthine system, however, was found to be much potent as compared to that observed in potassium superoxide system. It was further shown that resveratrol could also directly inhibit xanthine oxidase activity as assessed by oxygen consumption and formation of uric acid. Taken together, the dual role of resveratrol in directly scavenging superoxide and inhibiting its generation via xanthine oxidase reported in this study may explain, at least in part, the protective role of this compound against oxidative injury in various disease processes.
authors.affiliation: Division of Biomedical Sciences, Edward Via Virginia College of Osteopathic Medicine, Virginia Tech Corporate Research Center, 2265 Kraft Drive, Blacksburg, VA 24060, USA.
authors.forename: Zhenquan
authors.initials: Z
authors.lastname: Jia
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.forename: Bhaba R
authors.initials: BR
authors.lastname: Misra
authors.forename: James E
authors.initials: JE
authors.lastname: Mahaney
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Li
authors.forename: Hara P
authors.initials: HP
authors.lastname: Misra
mesh_terms: D019587:Dietary Supplements; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000378:metabolism / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D011758:Pyrroles; D000077185:Resveratrol; D013113:Spin Labels; D013267:Stilbenes / Q000378:metabolism / Q000494:pharmacology*; D013481:Superoxides / Q000378:metabolism*; D014527:Uric Acid / Q000378:metabolism; D019820:Xanthine / Q000378:metabolism; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: C510912:(diethoxyphosphoryl)-5-methylpyrroline N-oxide; D016166:Free Radical Scavengers; D011758:Pyrroles; D013113:Spin Labels; D013267:Stilbenes; D013481:Superoxides; D019820:Xanthine; D014527:Uric Acid; D014969:Xanthine Oxidase; D000077185:Resveratrol