ISSN: 2161-1149 (Printed)
Introduction: The aim of this study was to evaluate the relationship between oxidative stress and pulmonary involvement and its severity in patients with systemic sclerosis (SSc).
Materials and Methods: 34 patients (30 female, 4 male) and 27 healthy volunteers (21 female, 6 male) were included into the study. All patients fullfilled the American College of Rheumatology criteria for the diagnosis of SSc.
Oxidant-antioxidant enzymes malondialdehyde (MDA), Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), xanthine oxidase (XO), and adenosine deaminase (ADA) enzyme activities were measured by spectrophotometric methods.
Results: Plasma ADA levels was significantly higher in patients than the control group. On contrary, XO levels of erythroctes were lower. Of 34 patients, 11 had no pulmonary involvement, 14 had mild to moderate and 9 had severe-end stage pulmonary involvement. In patients with pulmonary involvement, plasma XO level was statistically significantly lower but intraerythrocyte XO levels were higher (not statistically significant) than the patients without pulmonary involvement. Severe-end stage group had significantly higher intraerythrocyte XO activity. In limited early disease, intraerythrocyte SOD level was significantly lower than the other groups. Plasma MDA level was significantly higher in limited early and diffuse early disease. Plasma MDA, GSH-PX and intraerythrocyte ADA levels were negatively correlated with disease duration. Intraerythrocyte MDA level was positively correlated with pulmonary arterial pressure.
Conclusions: This study may show that besides the role in the pathogenesis of systemic sclerosis, oxidative stress may also play a role in the severity of the pulmonary involvement of the disease.