Superoxide dismutase and glutathione peroxidase in erythrocytes of patients with iron deficiency anemia: effects of different treatment modalities.

AIM To test whether the activities of erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) can be affected by oral iron (OI) treatment, parenteral iron (PI) treatment, and parenteral iron treatment with vitamin E supplementation (PIE) in iron deficiency anemia. METHODS Twenty-eight patients with iron deficiency anemia and 18 healthy controls were included in the study. Anemic patients were systematically allocated into 3 treatment groups. The first group (n=8) received OI, the second group (n=10) PI, and the third group (n=10) PIE. SOD and GSH-Px activities were determined using commercial kits. RESULTS Before the treatment, SOD activity was significantly lower in anemic patients than in the control group (Kruskal-Wallis test, p<0.05). After the treatment, SOD activity significantly increased in all three patient groups and reached the values found in the control group (Wicoxon signed-rank test, p=0.017 for OI, p=0.047 for PI, and p=0.037 for PIE group). Before the treatment, GSH-Px activities in anemic patients were similar to that of control group (Kruskal-Wallis test, p>0.05). Although there was no significant decrease in GSH-Px activity after OI treatment, both PI and PIE treatments significantly decreased GSH-Px activity (Wilcoxon signed-ranks test, p=0.007 for PI and p=0.005 for PIE). PIE was more effective than PI treatment in maintaining GSH-PX activity. CONCLUSION Oral iron treatment improved the iron deficiency anemia and recovered antioxidant defense system by increasing SOD activity and maintaining GSH-Px activity at normal level. When parenteral iron treatment is inevitable, vitamin E supplementation together with PI treatment may be effective in partially restoring the antioxidant status in this type of anemia.