The interaction of reduced glutathione with active oxygen species generated by xanthine-oxidase-catalyzed metabolism of xanthine.
The interaction of reduced glutathione (GSH) with active oxygen species generated during xanthine-oxidase-catalyzed metabolism of xanthine was investigated. The only GSH-derived product detected in this system was oxidized glutathione (GSSG). Catalase inhibited the oxidation of GSH to GSSG by more than 80%, whereas superoxide dismutase exerted a smaller but significant inhibition of GSSG formation. Hydroxyl radical (OH) scavengers or desferrioxamine (1 mM) had no effect on GSSG formation. Using EPR spectroscopy and the spin trap 5,5-dimethylpyrroline-N-oxide (DMPO), the production of superoxide was observed by the detection of a DMPO-OOH radical adduct. This spectrum was altered by the inclusion of GSH (5 - 20 mM) in the reaction mixture, indicating the generation of a different radical species consistent with DMPO-glutathionyl radical adduct generation.
Ross
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D
Cotgreave
I
I
Moldéus
P
P
D002374:Catalase / Q000378:metabolism; D003497:Cyclic N-Oxides; D003676:Deferoxamine; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D005978:Glutathione / Q000378:metabolism*; D006878:Hydroxides; D010084:Oxidation-Reduction; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D019820:Xanthine; D014969:Xanthine Oxidase / Q000378:metabolism; D014970:Xanthines / Q000378:metabolism
D003497:Cyclic N-Oxides; D005609:Free Radicals; D006878:Hydroxides; D014970:Xanthines; D013481:Superoxides; D019820:Xanthine; C017245:5,5-dimethyl-1-pyrroline-1-oxide; D002374:Catalase; D013482:Superoxide Dismutase; D014969:Xanthine Oxidase; D005978:Glutathione; D003676:Deferoxamine