Study of the Effects of N-acetylcysteine on Inflammatory Biomarkers and Disease Activity Score in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is considered as an autoimmune-related condition in which the overproduction of pro-inflammatory cytokines leads to an inflammatory cascade. N-acetylcysteine (NAC) is a potent anti-inflammatory and anti-oxidant agent. We aimed to explore the impact of oral NAC on cytokines activities and clinical indicators in RA patients. In this placebo-controlled randomized double-blind clinical trial, 41 active RA patients were allocated in either NAC (600 mg, twice a day) or placebo group, as add-on therapy to the routine regimen, for 8 weeks. Disease activity score with an erythrocyte sedimentation rate (DAS28-ESR), and serum concentrations of interleukin (IL)-1β and IL-17 were assessed at baseline and end of the trial for all participants in the test and control groups. The reduction of the DAS28-ESR was higher considerably in the NAC group compared to that of the control group. No statistically significant differences were seen in the reduction of IL-1β and IL-17 cytokines between the NAC and control groups. In addition, improvements in the patient global assessment, number of tender joints, number of swollen joints, and the ESR rates were in favor of the NAC group. Our findings reveal that NAC may have a beneficial effect on all of the clinical features of RA. However, non-significant variations in the IL-1β and IL-17 levels suggest an alternative way of NAC effectiveness without influencing the measured cytokines. Nevertheless, these results need to be confirmed by further investigations.