Effect of Thymoquinone on Th1 and Th2 Balance in Rats Infected with Mycobacterium tuberculosis

Thymoquinone is an active compound in Nigella sativa which has potential immunomodulatory effect. Mycobacterium tuberculosis could alter the Th1 and Th2 balance by stimulating phagocyte IL-1β production, and subsequent Th2 differentiation. We aim to evaluate the effect of thymoquinone (TQ) in restore the Th1 and Th2 balance in Mycobacterium tuberculosis infection. Four groups of rats were infected with virulent Mycobacterium tuberculosis strain H37Rv. Thymoquinone at different doses was given to three groups, and one group left without treatment. Additional one group was either infected or treated with TQ. We measure IL-1β, IL-4 and IFN-γ levels using ELISA 14 days after TQ treatment. We found there were increased IL-1β, IL-4 and IFN-γ level after Mycobacterium tuberculosis infection, but we observe no significant effect of TQ treatment to Th1 and Th2 balance.  We conclude that TQ could not restore Th1 and Th2 balance in rats infected with Mycobacterium tuberculosis.