Effects of Probiotic Supplementation on Oxidative Stress Indices in Women with Rheumatoid Arthritis: A Randomized Double-Blind Clinical Trial

Objective : Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that causes great pain and disability and increasing oxidative stress in patients. The objective of the present study was to evaluate the effects of probiotics—live microorganisms with many health benefits, including antioxidant properties—on oxidative stress indices of patients with RA. This study is a secondary analysis from a previously published study Methods : In a randomized double-blind placebo-controlled clinical trial, 46 patients with RA were assigned to one of two groups; patients in the probiotic group received a daily capsule containing 10 ⁸ colony forming units (CFUs) of Lactobacillus casei 01 (L. casei 01), while those in the placebo group took identical capsules containing maltodextrin, for 8 weeks. In the baseline and at the end of the study, anxiety, physical activity levels, and dietary intakes were assessed. Anthropometric parameters, serum malondialdehyde (MDA), total antioxidant capacity (TAC), erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were measured. Results : There was no significant difference between the two groups for demographic characteristics, anthropometric parameters, physical activity, anxiety levels, or dietary intakes, throughout the course of the study. No significant within- and between-group differences were observed for MDA, TAC, or CAT. SOD activity decreased only in the probiotic group and GPx activity decreased in both study groups (p < 0.05); however, no significant between-group difference was found for these enzymes activities at the end of the study (p > 0.05). Conclusion : No significant effect of L. casei 01 supplementation was observed on the oxidative status of patients with RA, compared to placebo.