Immunotherapeutic Effects of Glycyrrhiza glabra and Glycyrrhizic Acid on Leishmania major Infected BALB/C Mice.

AIM The objective of the current study was to investigate the Immunotherapeutic activities of the hydroalcoholic extract of Glycyrrhiza glabra (HEG) and glycyrrhizic acid (GA) in the treatment of Leishmania major (L. major) infection BALB/c mice. METHODS The effect of HEG, GA was checked in vitro on growth of L. major promastigote and amastigote using MTT assay and microscopic counting, respectively. For in vivo experiment, L. major infected BALB/c mice were treated intraperitoneally with HEG, GA, Meglumine antimonite, or phosphate buffer saline as a negative control for one month. Then, the cytokine response (IFN-γ and IL-4) to Leishmania antigens was evaluated using ELISA method. The parasite burden of the lymph node was assessed at the end of treatment. RESULTS HEG, and GA significantly inhibited growth of of L. major promastigotes and amastigotes. Although the lesion development, parasite burden in the lymph nodes, level of IFN-γ and the ratio of IFN-γ/IL-4 in HEG, GA and Meglumine antimonite treated mice were significantly higher compared with the negative control group, but there was no difference between the HEG, GA and Meglumine antimonite group. CONCLUSION The hydroalcoholic extract of G. glabra and glycyrrhizic have shown therapeutic and immunomodulatory effects on L. major infected BALB/c mice.