Glutathione-dependent protection against oxidative damage of the human red cell membrane

Glutathione (GSH) dependent protection against oxidative damage of human red cell membrane was examined. An artificial system was used in which chloroform/methanol-extracted red cell lipids, in the form of liposomes, were subjected to attack by a peroxidation system consisting of ascorbate-Fe3+. Human erythrocytes contained a nondialyzable factor, completely inactivated by heating in a boiling water bath for 3 min, which showed GSH-dependent inhibition against lipid peroxidation and was devoid of GSH peroxidase activity. On the other hand, GSH-S transferase, highly purified by affinity chromatography, had no inhibitory activity. These findings strongly indicate that the GSH-dependent protection against lipid peroxidation of human red cell membrane is mediated by one or more proteins other than GSH peroxidase and GSH-S transferase.