Kombucha ameliorates experimental autoimmune encephalomyelitis through activation of Treg and Th2 cells

Multiple sclerosis (MS) is the most common inflammatory disorder of the central nervous system (CNS). Kombucha is produced by the fermentation of sugared tea with a symbiotic culture of bacteria and yeasts. This research was designed to reveal the therapeutic impact and the molecular and cellular processes determining the effect of kombucha on MS alleviation in an experimental autoimmune encephalomyelitis (EAE). The EAE was induced using myelin oligodendrocyte glycoprotein (MOG_35-55) peptide emulsified in CFA and injected subcutaneously over two flank areas in C57BL/6 mice. In addition, pertussis toxin was injected intraperitoneally and repeated 48 h later. Treatment groups were received three different doses of kombucha (K1: low dose, K2: medium dose and K3: high dose) to obtain a maximum protection. Clinical scores and other criteria were followed daily for the 25 days. At the end of the course, T-helper-related cytokines (IFN-γ, IL-17, IL-4, and TGF-β) were measured through ELISA. Moreover, nitric oxide (NO) concentration in spinal cord tissue was detected. The severity of disease on the peak of disease in K1, K2, and K3 groups were 3.4 ± 0.18 and 2.6 ± 0.18 and 2 ± 0.14 respectively, compared to the CTRL group with 4.5 ± 0.19 (p < 0.001). Kombucha increased production of interleukin IL-4 (K1 = 95 ± 5, K2 = 110 ± 10, K3 = 115 ± 5 and CTRL = 65 ± 5; p < 0.05) and TGF-β (K1 = 1750 ± 80, K2 = 2050 ± 65, K3 = 2200 ± 75 and CTRL = 850 ± 85; p < 0.001) but concurrently resulted in a remarkable reduction in the production of IFN-γ (K1 = 950 ± 70, K2 = 890 ± 65, K3 = 850 ± 85 and CTRL = 3850 ± 115; p < 0.001) and IL-17 (K1 = 1250 ± 75, K2 = 1050 ± 90, K3 = 970 ± 80 and CTRL = 6450 ± 125; p < 0.001). Moreover, NO concentration in spinal cord tissue in the treatment groups was significantly less than the control group (K1: 35.42 ± 2.1, K2 = 31.21 ± 2.2, K3 = 28.24 ± 2.6 and CTRL = 45.25 ± 2.7; p < 0.05). These results supported that kombucha could reduce the severity of disease in an EAE model through motivating polarization of CD4⁺ T cells by induction of IL-4 and TGF-β as well as inhibition of IFN-γ and IL-17.