Artículo de revista
Cu(I)-Glutathione complex: A potential source of superoxide radicals generation
Fecha
2008Registro en:
Bioorganic and Medicinal Chemistry, Volumen 16, Issue 13, 2008, Pages 6568-6574
09680896
10.1016/j.bmc.2008.05.026
Autor
Speisky Cosoy, Hernán
Gómez, Maritza
Carrasco Pozo, Catalina
Pastene, Edgar
López Alarcón, Camilo
Olea Azar, Claudio
Institución
Resumen
Cu(2+) ions and and GSH molecules interact swiftly to form the complex Cu(I)–glutathione. We investigated the potential capacity of such complex to reduce molecular oxygen. The addition of SOD to a solution containing Cu(I)–glutathione led to a sustained decline of the basal oxygen level. Such effect was partially reverted by the addition of catalase. The complex was able to induce the reduction of cytochrome c and the oxidation of dyhydroethidium into 2-hydroxyethidium. Both effects were totally blocked by SOD. The ability of the complex to generate superoxide radicals was confirmed by EPR spin-trapping. Cu(I)–glutathione induces no oxidation of fluorescein, a hydroxyl radical-sensitive probe. We conclude that in solutions containing the complex, oxygen is continually reduced into superoxide, and that—in absence of interceptors—the latter radicals are quantitatively re-oxidized into molecular oxygen. We suggest that, by functioning as a continuous source of superoxide, the complex could potentially affect a broad range of susceptible biological targets.