Oxidation status of β-thalassemia minor and Hb H disease, and its association with glycerol lysis time (GLT50).

β-Thalassemia (β-thal), especially β-thalassemia major (β-TM), is reported to be related to reactive oxygen species (ROS) and enhanced oxidation status. It is reflected by increased malondialdehyde (MDA), by membrane lipid peroxidation and decreased by the newly developed total antioxidant capacity (TAC). However, there is less evidence for β-thal minor and Hb H (β4) disease on its association with oxidation status. On the other hand, hemolysis by glycerol lysis time (GLT50) is invariably prolonged in thalassemia. The reason for the prolongation of GLT50 is not well understood. The aim of this study was to investigate the oxidation state in β-thal minor and Hb H disease and to find out the association of the oxidation with the prolongation of GLT50. Blood samples from 39 subjects (33 with β-thal minor, six with Hb H disease) were collected from individuals living in Japan. The clinical screening tests and molecular identification of the thalassemias were performed. Malondialdehyde and TAC were measured using spectrophotometric analyses. In β-thal minor and Hb H disease, the plasma MDA level was significantly elevated and the TAC reduced. A highly reversed correlation between MDA and TAC was noted. Their GLT50 levels were evidently prolonged, and the GLT50 has significant correlations with MDA and TAC. β-Thalassemia minor and mild Hb H disease are evidently in a milieu of reduced redox state, and GLT50 prolongation in β-thal minor and Hb H disease has a close correlation with the oxidation state, possibly by oxidative impairment of the membrane protein of the red cell.