Role of Free Radicals in Diabetic Vascular Disease

Free radicals, however, satisfy other criteria required for an important role in the pathogenesis of diabetic vascular disease  

Free-radical-induced oxidation of low-density lipoprotein (LDL) may be another mechanism that leads to tissue injury. Following incubation with endothelial or smooth muscle cells, LDL oxidizes and becomes toxic to proliferating fibroblasts (Morel et al., 1983a). 

The cytotoxicity of LDL can also be inferred from the study by Blake et al. (1985). In this study of human cultured endothelial cells, stored sera from patients with necrotizing arteritis demonstrated an enhanced tendency to develop oxidized LDL, which correlated closely with endothelial cell cytotoxicity. This process appears to require the presence of both oxygen and transition metal ions such as iron in the presence of a reducing agent (Gebicki ef /., 1991). There is considerable evidence that transition metals are involved in cell-induced modifications of LDL including the inhibitory effects of EDTA and desfer-rioxamine (Hiramatsu et 1987). A role for Of in LDL modification by endothelial cells and fibroblasts comes from studies showing inhibition of LDL oxidation by SOD (Steinbrecher, 1988). 

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