We aimed to investigate the extent of alterations in the pro/antioxidant balance in the blood of patients with relapsing-remitting multiple sclerosis (RRMS) in relation to drug-modified therapy, gender, disability score, and disease duration. 161 patients (67 men and 94 women, aged 24-69 years, median 43.0) and 29 healthy individuals (9 men and 20 women, aged 25-68 years, median 41.0) were included in the study. We measured the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) as well as the concentration of interleukin-6 (IL-6), lipid peroxidation parameters (LPO), total oxidant status (TOS), and total antioxidant capacity (TAS). The activity of SOD did not show any significant differences between patients with RRMS and the control group in our study. In contrast, significant decreased GPx activity and increased CAT activity was observed in the blood of patients with RRMS compared to the control group. Additionally, the activity of CAT was influenced by gender and the use of disease-modifying therapies. Disease-modifying therapies also affected the concentration of TOS, TAS, and LPO. Our studies indicated that enhancing GPx activity may be more beneficial to providing potential therapeutic strategies aimed at modulating antioxidant defenses to mitigate oxidative stress in this disease.
Keywords: antioxidants; oxidative stress; relapsing–remitting multiple sclerosis.