Reduced glutathione, superoxide dismutase contents and malondialdehyde formation in platelets from uremic patients: relation to plasma and platelet zinc

Platelet-reduced glutathione (GSH), superoxide dismutase (SOD) and zinc content as well as malondialdehyde (MDA) formation were studied in 55 healthy volunteers as controls and 49 patients with chronic renal failure. Uremic patients had a significantly lower GSH and SOD content as well as an abnormal MDA formation in their platelets. Their plasma zinc level was sharply below the normal value, but their platelet zinc content was similar to that of normal controls. We also found that the plasma zinc and platelet zinc level was positively correlated to the platelet GSH content in normal controls and uremic patients. Therefore, the results suggest that in uremic patients the decrease in platelet antioxidant agents (GSH and SOD) may be partially related to their low plasma zinc level.