Antioxidant defense status of red blood cells of patients with β-thalassemia and Eβ-thalassemia

Anemia in beta -thalassemia is caused by a combination of ineffective erythropoiesis and premature hemolysis of RBC in the peripheral circulation. Excess of the cr-globin chain present in beta -thalassemic RBC is mainly responsible for oxidative damage of erythrocyte membrane protein. The activities of glucose-6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase, and the catalytic activity of catalase and superoxide dismutase, and the concentrations of non-enzymic antioxidants such as reduced glutathione were measured to estimate the status of the antioxidant defense system in the erythrocytes for protection against oxidative stress. The extent of lipid peroxidation was also estimated in thalassemic erythrocytes. Significantly lower activities of reduced glutathione indicate the cell to be in a pro-oxidant state and decreased activity of catalase favors hydrogen peroxide-mediated lipid peroxidation in beta -thalassemic and E beta -thalassemic RBC. (C) 2001 Elsevier Science B.V. All rights reserved.