Detection of nitrotyrosine in the diabetic plasma: evidence of oxidative stress (original) (raw)

The relation between diabetes and premature vascular disease is well established [1] and oxidative stress has been claimed as one of the most important pathogenetic factors [2]. In diabetes, oxidative stress could increase the production of superoxide (O 2-) and nitric oxide (NO) [2±3], which could lead to the formation of pro-oxidant peroxynitrite (ONOO-) [4]. The ONOO-, formed by the reaction between NO and O 2-, is a powerful oxidant capable of oxidizing low density lipoprotein [5], of causing vascular dysfunction [6] and of nitrating tyrosine residues in proteins [7]. Because the production of ONOOis difficult to determine, the assay of nitrotyrosine in protein has been proposed as an indirect marker of ONOOproduction [7]. The presence of nitrotyrosine in biological fluids such as plasma and urine have been investigated in a limited number of conditions. Raised values of nitrotyrosine have been found in the plasma of patients Diabetologia (2001) 44: 834±838