The susceptibility of red blood cells to autoxidation in type 2 diabetic patients with angiopathy

We examined the in vitro susceptibility of red blood cell (RBC) lipids to o xidation in type 2 diabetic patients with or without angiopathy. Lipid pero xidation was assessed by quantifying thiobarbituric acid (TBA) reactivity a s malondialdehyde (MDA). We also examined the RBC antioxidant status by det ermining glutathione (GSH) levels. Before in vitro oxidation, RBC MDA level s were significantly higher in both diabetic groups than in the controls (P <.001), and a significant difference was found between the two diabetic gr oups (P <.05). Alter in vitro treatment of RBCs with hydrogen peroxide, the degree of lipid peroxidative damage was significantly higher in diabetic p atients with angiopathy versus diabetics without angiopathy (P <.001). Diab etic patients have low RBC GSH levels compared with controls, and after in vitro oxidation, the levels were significantly decreased in diabetics (P <. 001). There was not a significant correlation between RBC MDA levels and gl ycated hemoglobin (GHb), plasma cholesterol, and triglyceride. The correlat ion between RBC MDA and GSH was weak (P <.001). We suggest that the results of this study might help to clarify the role of oxidative mechanisms as an in vitro model of degenerative damage in type 2 diabetic angiopathic compl ications. Copyright (C) 1999 by W.B. Saunders Company.