Resumo

MIRANDA, M et al. Oxidative stress in a model for experimental diabetic retinopathy: treatment with antioxidants. Arch Soc Esp Oftalmol [online]. 2004, vol.79, n.6, pp.289-294. ISSN 0365-6691.

Purpose: Diabetic retinopathy is the primary cause of blindness in developed countries, and though strict glycemic control is desirable to prevent complications, this is not always achievable. Thus, adjunctive therapies are needed to help in preventing or delaying the onset of diabetic complications. We have studied the biochemical and functional changes in the retina of diabetic mice, and the ability of ebselen and lutein, two antioxidants, to reverse these effects, using as a comparison the effect of insulin therapy. Methods: Alloxan injection was used to achieve hyperglycemia. Malondialdehyde (MDA) concentration in blood and glutathione peroxidase (GPx) activity in eye homogenate were measured. Serial electroretinograms (ERG) were recorded. Results: MDA concentration in the blood was high in diabetic animals. GPx activity in eye homogenate decreased in the diabetic conditions. Maximal electroretinogram amplitude decreased in diabetic animals with respect to controls. Ebselen and lutein restored MDA levels, GPx activity and ERG amplitude, and had no effect on glycemia. Conclusion: These results call for further studies on ebselen or lutein as adequate adjunctive therapies for diabetes.

Palavras-chave : Diabetes; mouse; ebselen; lutein; oxidative stress; electroretinogram; antioxidants.