The role of the oxidative state of glutathione and glutathione-related enzymes in anemia of hemodialysis patients.

OBJECTIVE: To investigate the oxidative state of glutathione and glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R), and glucose-6-phosphate dehydrogenase (G-6-PD) levels in patients with chronic renal failure (CRF) and controls. RESULTS: Erythrocyte GSH levels of patients were decreased, but GSSG was not significantly different from that of controls. Also, plasma GSH levels were not different, although GSSG was increased. GSSG/GSH ratios in erythrocyte and plasma were significantly higher in CRF patients. Erythrocyte GSSG-R activity was high, but G-6-PD and GPX were low. CONCLUSIONS: The findings suggest that: 1. Low GSH is related to decreased G-6-PD activities. 2. The reduction of peroxides with GPX are decreased by low GSH and low GPX activity. 3. GSSG may react with hemoglobin and causes protein aggregation in erythrocytes. These alterations cause hemolysis and could play a role in the pathogenesis of anemia in hemodialyzed patients.