RESUMO
Bioflavonoids (polyhydroxyphenols) are ubiquitous components of plants, fruits and vegetables; these compounds are efficient scavengers of free oxygen radicals and peroxides. The aim of this study was to investigate the antioxidative effects of genistein-8-C-glycoside (G8CG) isolated from the flowers of Lipinus luteus L. G8CG dose-dependently inhibited membrane lipid peroxidation and prevented GSH oxidation in human red blood cells and rat liver homogenates under tert-butylhydroperoxide-induced oxidative stress and single whole-body gamma-irradiation (1 Gy) of rats.
Assuntos
Antioxidantes/farmacologia , Eritrócitos/efeitos dos fármacos , Raios gama , Genisteína/análogos & derivados , Glucosídeos/farmacologia , Fígado/efeitos dos fármacos , Estresse Oxidativo , Animais , Antioxidantes/isolamento & purificação , Células Cultivadas , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Genisteína/isolamento & purificação , Genisteína/farmacologia , Glucosídeos/isolamento & purificação , Humanos , Fígado/metabolismo , Fígado/efeitos da radiação , Lupinus/química , Masculino , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Ratos , Irradiação Corporal TotalRESUMO
Erythrocyte damage induced by hypochlorous acid (HOCl) results in cell lysis developing with time after the oxidant is removed (post-hemolysis). The apparent rate constant of post-hemolysis depends on time of incubation in the presence of HOCl and concentration of this oxidant. HOCl-dependent damage of erythrocyte membranes is associated with uncompetitive inhibition of the membrane-bound acetylcholinesterase. Genistein-8-C-glucoside is an isoflavonoid isolated from the flowers of Lupinus luteus L.; in aqueous solution, genistein-8-C-glucoside (0.5-2 mM) efficiently inhibited HOCl-induced damage to erythrocytes similar to the known HOCl scavengers taurine and reduced glutathione. This bioflavonoid can protect the erythrocyte membrane (and to a lesser extent, intraerythrocytic components) by interacting with the reactive chlorine species including hypochlorous acid and membrane-bound chloroamines formed in the reaction of HOCl with erythrocyte membrane proteins.