Effects of Nigella sativa oil extract on inflammatory cytokine response and oxidative stress status in patients with rheumatoid arthritis: a randomized, double-blind, placebo-controlled clinical trial

Abstract

Objectives:<em> Nigella sativa</em> is a medicinal plant that has long been used in traditional medicine for treating various conditions. Numerous animal studies provided evidences that the seed may elicit a broad anti-inflammatory/anti-oxidant activity. The aim of the present clinical trial was to evaluate anti-inflammatory and antioxidant properties of <em>Nigella sativa</em> oil in patients with rheumatoid arthritis (RA). <br/>Materials and Methods: Forty-two patients with RA were assigned into two groups in this randomized, double blind, placebo-controlled clinical trial. Subjects in intervention group received two capsules, 500 mg each, of <em>Nigella sativa</em> oil, each day for 8 weeks. The other group consumed two capsules as placebo per day for the same period of time. Serum TNF-α, IL-10, and whole blood levels of oxidative stress parameters were measured at baseline and end of the trial. <br/>Results: The serum level of IL-10 was increased in the <em>Nigella sativa</em> group (p<0.01). Moreover, treatment with <em>Nigella sativa</em> led to significant reduction of serum MDA and NO compared with baseline (p<0.05). There were no significant differences in the TNF-α, SOD, catalase, and TAS values between or within the groups, before and after the intervention (p>0.05). <br/>Conclusions: This study indicates that <em>Nigella sativa</em> could improve inflammation and reduce oxidative stress in patients with RA. It is suggested that <em>Nigella sativa</em> may be a beneficial adjunct therapy in this population of patients