DNA damage levels in systemic lupus erythematosus patients with low disease activity: An evaluation by comet assay

Oxidative stress has been implicated in the inflammatory process of Systemic Lupus Erythematosus (SLE), particularly by the formation of anti-DNA autoantibodies, which can lead to DNA damage. The aim of this study was to investigate, through comet assay, whether the level of DNA damage in SLE patients is different from that of healthy subjects. Twenty-five adult SLE patients with SLEDAI up to ten, and 25 healthy subjects were paired according to age, gender and Body Mass Index (BMI). Other anthropometric variables were also assessed. Comet assay was assessed as the marker of oxidative stress described as DNA Damage (DD) percentage. Waist Circumference (WC), Hip Circumference (HC) and BMI were also performed. Exclusion criteria for patients and controls comprised smoking and other chronic disorders. Level of damage index was remarkably higher in SLE patients than in controls, and no significant differences between the groups were found for age, BMI, WC and HC. No stratification concerning gender was performed, since there were just two males per group. No correlation was observed between BMI and DD (%). DD increased in SLE, which reflects the oxidant/antioxidant imbalance in these patients. These findings support an association between oxidative stress and SLE. This stronger correlation observed in patients with low disease activity may be useful in elucidating the mechanisms of disease pathogenesis.