The effect of narrow band UVB treatment on oxidative stress in vitiligo patients

Vitiligo is a common acquired pigmentary disorder of the skin and mucoses with selective destruction of melanocytes. The pathogenetic mechanisms of vitiligo have not yet been completely clarified. One of the major hypothesies in the pathogenesis of vitiligo is the oxidative stress hypothesies. In this study we aimed to evaluate the possible role of oxidative stres in the pathogenesis of vitiligo by measuring the values of erythrocyte malondialdehyde (MDA) levels, and erythrocyte activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in generalized vitiligo patients and healthy control subjects. Also we purposed to find out if these parameters are affected or not in the patients after narrow band ultraviolet B (UVB) treatment.Twenty-four patients with generalized vitiligo and twenty-seven healthy controls were enrolled in this study. We assessed erythrocyte levels of MDA as well as erythrocyte activities of SOD and GSH-Px. We applied narrow band UVB treatment to the patient group three days in a week for six months. After the end of the treatment we measured the same parameters again. We found significantly higher levels of MDA (p=0.001), and a significantly lower erythrocytes SOD and GSH-Px (p=0.045 and (p=0.001) activities in patients with vitiligo compared with the control subjects. We also found significantly decreased levels of MDA (p=0.001), and significantly increased erythrocyte GSH-Px activities (p=0.024) after narrow band UVB treatment. However, the decreases in the erythrocytes activities of SOD (p=0.808) were insignificant.In conclusion ,our findings suggest that oxidative stress may have an important role in the pathogenesis of vitiligo. In vitiligo treatment narrow band UVB therapy may be usefull by affecting the oxidative stres in addition to its other therapeutic effects. Furthermore, it may be speculated that additional topical or/and systemic antioxidants can provide more clinical benefits. However, further controlled studies with larger study population are needed to demonstrate this hypothesis.Key Words: Malondialdehyde (MDA), Superoxide Dismutase (SOD), Glutathione peroxidase (GSH-Px), Narrow band UVB, Oxidative stress, Vitiligo.