Artemisia dracunculus L. modulates the immune system in a multiple sclerosis mouse model

Background: Multiple sclerosis along with its animal model, experimental autoimmune encephalomyelitis (EAE), are chronic inflammatory and degenerative diseases of the central nervous system (CNS). Due to the unknown cause of the disease, the most common treatments of MS are targeted for the reduction of inflammation and the repairment of CNS tissue damage, especially myelin restoration. Due to the immune protective nature of herbs, it may be useful to evaluate the impact of herbs in the diet regimen of MS patients along with their immune-mediated effects. The purpose of this study was to investigate the effect of an aqueous extract of Artemisia dracunculus (Tarragon) on the treatment of EAE in C57BL/6 mice.Methods: In this experimental study, mice were divided into the following control, untreated EAE, and A. dracunculus treated EAE groups. EAE was induced by myelin oligodendrocyte glycoprotein (MOG35-55) in female C57BL/6 mice. The symptoms of the disease and the weight of the mice were recorded daily. On day 33 after EAE induction, the mice were sacrificed and the specimens were collected. Cell proliferation and cytokine release (TGF-β, IL-17 and IL-23) from mice cultured spleen cells was measured by 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and ELISA respectively.Results: Administration of the extract of A. dracunculus mitigated EAE symptoms (P < 0.05). Furthermore, there was a reduction in the levels of inflammatory cytokines including IL-17 (P = 0.009) and IL-23 (P = 0.012) and confirmed increased serum antioxidant levels in A. dracunculus treated EAE mice (P = 0.008).Conclusions: These observations indicate that A. dracunculus extracts could reduce inflammatory cytokines and attenuate certain signs of EAE, suggesting the potential of a useful adjuvant therapy for MS.