Effect of Conjugated Linoleic Acid, Vitamin E, Alone or Combined on Immunity and Inflammatory Parameters in Adults with Active Rheumatoid Arthritis: A Randomized Controlled Trial

Little information about the effects of conjugated linoleic acids (CLAs) on inflammation and immune function in humans is available. This study investigated the effects of CLAs, with and without Vitamin E on immunity and inflammatory parameters in adults with active rheumatoid arthritis (RA). In a double‑blind clinical trial, 78 patients were randomly divided into four groups, each group receiving one of the following daily supplement for 3 months; group C: 2.5 g CLAs, group E: 400 mg Vitamin E, group CE: CLAs plus Vitamin E, group P: Placebo. Cytokines, matrix metalloproteinase 3 (MMP‑3) and citrullinated antibody (CCP‑A) were measured by ELISA method and Vitamin E by high‑performance liquid chromatography. Consider statistical methods there were no significant differences between groups in cytokines interleukin‑2 (IL‑2), IL‑4, tumor necrosis factor‑α (TNF‑α), IL‑1β, IL‑2/IL‑4, CCP‑A white blood cells and neutrophils, lymphocyte, monocytes, and eosinophils numbers. TNF‑α decreased in all groups, but its reduction was significant in group CE. IL‑1β increased in groups P (P = 0.004) and E (P = 0.041) but the difference between group P and CE was significant. IL‑4 decreased in groups C, CE and E (P = 0.03, P = 0.03, P = 0.07 respectively). IL2 did not change significantly within groups. CCP‑A increased in groups P (P = 0.035) and E (P = 0.05), while it decreased in groups CE (P = 0.034). CCP‑A and MMP‑3 decrease were significant between groups P and CE. MMP‑3 reduction was significant in group CE. Co‑supplementation CLAs and Vitamin E may be effective in the level of inflammatory markers in RA patients.