Melatonin reduces oxidative stress in the erythrocytes of multiple sclerosis patients with secondary progressive clinical course

•We examined melatonin in the reduction of oxidative stress in multiple sclerosis.•We estimated lipid peroxidation and main antioxidative enzymes.•The results were verified with functional state.•Melatonin caused significant increase of antioxidative enzymes in MS.•We showed positive correlation between SOD and EDSS.

Oxidative stress plays a major role in multiple sclerosis (MS). Melatonin is a potent neuroprotectant. The aims of this study were to determine the actions of melatonin in the reduction of oxidative stress in MS. Therefore, we estimated lipid peroxidation and activities of main antioxidative enzymes in the red blood cells (RBCs) from selective group of MS patients only with secondary progressive (SPMS) clinical form and verified results with functional state. The sixteen (n = 16) SPMS patients were supplemented with melatonin (10 mg daily/30 days). Age matched healthy subjects were used as a control (n = 13). We determined the level of lipid peroxidation by malondialdehyde (MDA) and activities of main antioxidative enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxide (GPx) in RBCs of SPMS patients. Melatonin caused statistically significant increase of SOD, GPx (p < 0.0001 and p = 0.004065, respectively) and decrease of MDA in erythrocytes of SPMS patients (p = 0.00019). Correlation analysis of Spearman showed positive correlation between SOD and (expanded disability status scale) EDSS scale both before (r = 0.64, p = 0.00756) and after (r = 0.634, p = 0.00834) melatonin treatment. These results demonstrate that supplementation with melatonin SPMS patients should be taken into account, especially in progressive form of MS.