Effects of Alpha-Lipoic Acid Supplementation on Inflammatory Biomarkers and Matrix Metalloproteinase-3 in Rheumatoid Arthritis Patients

OBJECTIVE: Although many studies have considered alpha-lipoic acid (ALA) as a potent antioxidant with anti-inflammatory functions in oxidative stress-associated inflammatory diseases, few studies have evaluated its efficacy in rheumatoid arthritis (RA). Therefore, we aimed to examine the effects of ALA on serum biomarkers of joint damage and inflammation in women with RA. METHODS: We performed a randomized, double-blind, placebo-controlled clinical trial in which RA patients (n = 70) aged 20-50 years were randomly assigned 1:1 to receive either ALA (1200 mg/day) or placebo for 8 weeks. Fasting blood samples were taken before and after the study to analyze inflammatory biomarkers including serum high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and serum matrix metalloproteinase-3 (MMP-3) as a marker of joint erosion. Moreover, 3-day dietary records, the International Physical Activity Questionnaire (IPAQ), and the Spielberger State-Trait anxiety inventory form Y (STAI-Y) were assessed before and after the intervention. RESULTS: Sixty-five RA patients completed the trial. No statistically significant differences were observed in serum levels of hs-CRP, TNF-α, IL-6, and MMP-3 within and between the ALA and placebo groups (p > 0.05). There were no statistically significant differences in dietary intakes, physical activity, and anxiety levels between groups at baseline and they remained statistically unchanged during the study period (p > 0.05). CONCLUSION: Although in theory ALA supplementation could serve as a beneficial nutraceutical in RA patients, in the present study serum inflammatory biomarkers and MMP-3 were not significantly affected by 8 weeks of ALA supplementation.