[Role of oxidative stress in the maintenance of inflamation in patients with juvenile rheumatoid arthritis].

OBJECTIVE

To determine the level of cellular oxidative stress blood markers and the enzymatic system of antioxidant defense establishing the oxidative profile in patients with Juvenile Rheumatoid Arthritis. METHODS: Case-control study that included 64 patients (46 of female sex) with Juvenile Rheumatoid Arthritis (JRA) following clinical control in the Pediatric Rheumatology Service of the Vall dacute;Hebron Hospital, Barcelona, Spain. The patients were separated in three subtypes based on the pattern of onset within the first six months of disease: polyarticular, pauciarticular and systemic. The control group included 60 patients (38 of female sex) following clinical control to diseases of non inflammatory nature, in the same hospital. The plasmatic levels of malondialdehyde (MDA), lipoperoxide (LPO), hydroperoxide (HPX), carbonile groups (CG) of proteins and gluthathione and the enzymatic activities of Superoxide dismutase (SOD), gluthathione peroxidase (GSH-Px) and gluthathione reductase were determined. RESULTS: The group of patients with JRA presented high concentrations of lipid peroxidation products, evaluated by determining the plasmatic levels of MDA, LPO, and HPX; oxidative damage of the circulate protein, determined by CG contents of plasma proteins; elevation of enzymatic activity of SOD and GSH-Red; decrease of GSH-Px activity and GSH levels. CONCLUSIONS: Our results show the presence of molecular damage determined by oxygen free radicals in the JRA patients. The SOD activity and the changes of gluthathione redox enzymatic cycle confirm the decrease of capacity of cellular defense system against the induced toxicity of oxidative stress in these patients.