Influence of diabetes mellitus on the glutathione redox system of human red blood cells

ABSTRACT

Several components of the erythrocyte-dependent glutathione redox system (reduced glutathione, GSH; oxidized glutathione, GSSG; glutathione peroxidase, GSH-Px; glutathione reductase, GSH-Red) were determined in patients with types I and II diabetes mellitus (DM). All groups studied were male subjects: G1, 200 young healthy individuals (aged 23.7 ñ 4.2 years); G2, 15 young insulin-treated type I DM patients; G3, 20 older older insulin-treated type II DM patiens; G4, 21 older oral hypoglycemic agent-treated type II DM patients; G5, 28 aged healthy individuals (aged 68.9 ñ 11.5 years). There were no differences between G1 and G3 or G4 regarding erythrocyte GSH, GSSG, and GSH-Red (without FAD) levels. GSH-Px activity was significantly lower in G2 when compared to G1 (15.2 ñ 4.9 vs 20.6 ñ 6.6 IU/g Hb). The GSH-Red and GSH-Px activities and GSH levels were significantly higher in G3 (4.6 ñ 1.7 IU/g Hb, 20.2 ñ 8.7 IU/g Hb and 3.5 ñ 1.3 uM/g Hb) and G4 (5.0 ñ 2.2 IU/g Hb, 16.9 ñ 6.1 IU/g Hb and 5.0 ñ 2.3 uM/g Hb) when compared to G5 (3.4 ñ 0.9 IU/g Hb, 12.0 ñ 3.6 IU/g Hb and 2.3 ñ 0.9 uM/g Hb). The findings suggest that treatment of DM can stimulate the redox activity of red blood cells in aged subjects: