A systematic review and meta-analysis of randomized controlled trials to evaluating the trend of cytokines to vitamin A supplementation in autoimmune diseases.

BACKGROUND & AIMS Vitamin A is considered as a supplement that effect on autoimmune diseases. We aimed to systematically review the effect of vitamin A on cytokines in patients with autoimmune disease. METHODS Two researchers searched Scopus and PubMed until May 2018. Researchers extracted data from 6 eligible published papers. Extracted data included the gene expression of the inflammatory and anti-inflammatory cytokines. RESULTS Fixed effect analysis of the WMD (95% CI) of the changes in gene expression showed that gene expression of the inflammatory (IL-17, IFN-γ and T-bet) and anti-inflammatory (TGF-β and FOXP3) cytokines significantly decreased and increased due to vitamin A supplementation in patients with autoimmune (Multiple sclerosis and atherosclerosis) diseases. CONCLUSIONS Vitamin A supplementation effects on gene expression and may improve serum level of cytokines and clinical signs of autoimmune disease but there is no adequate evidence.