Evaluation of oxidative stress markers and vascular risk factors in patients with diabetic peripheral neuropathy.

Diabetic peripheral neuropathy (DPN) is one of the most common diabetic chronic complications. The pathogenesis of DPN is complex and involves an intertwined array of mechanisms. The purposes of this study were to evaluate the association of oxidative stress and vascular risk factors with the prevalence of DPN and to determine the role of these biochemical parameters in the prognosis of DPN. One hundred patients with type 2 diabetes mellitus and 40 clinically healthy individuals were evaluated. The patients were divided into two groups. Group 1 included 40 diabetic patients without peripheral neuropathy, and group 2 consisted of 60 patients with DPN. Erythrocytes glutathione (GSH) level, plasma malondialdehyde (MDA), nitrite/nitrate (NOx) and homocysteine (Hcy) levels as well as serum ceruloplasmin (Cp), total antioxidants (TAO), endothelin-1 (ET-1) levels and γ-glutamyl transferase (GGT) activity were estimated. A significant decrease of erythrocyte GSH was observed in groups 1 and 2 relative to the controls. An increase in glycosylated haemoglobin (HbA1c), MDA, NOx, GGT, Cp, TAO, Hcy and ET-1 was noted in patients with DPN. In conclusion, oxidative stress biomarkers and vascular risk factors could be important in the pathogenesis of DPN. The measurement of serum GGT and Hcy in addition to HbA1c and disease duration could facilitate the early detection of neuropathy in diabetic patients.