Peganum harmala and Nigella sativa: anti-leishmanial activity against Leishmania major promastigotes and amastigotes: in vitro and ex vivo experiment

Leishmaniosis is one of the most important vectors borne disease that is endemic in tropical and subtropical areas. There are many approved treatment for different types of leishmaniosis but all are with some adverse side effects that limited its uses. Here, we attempt to evaluate in vitro and ex vivo anti-leishmanial activities of Peganum harmala (P. harmala) and N. sativa (Nigella sativa) on promastigotes and amastigotes of L. major. The plants were extracted by maceration method and prepared in concentrations of 7.8, 3.9, 1.9, and 0.9 μg. L. major were cultured in RPMI-1640 medium alone and in J774 cell line separately. The extracts at different concentrations were assessed against promastigote (in vitro assay) and amastigotes (ex vivo assay) of L. major for 72 h at 22 and 37°C, respectively. In current work, N. sativa at highest concentration (7.8 μg/ml) showed 54.4 and 60% anti-leishmanial activity with IC50 of 5.3 and 3.278 μg/ml, respectively. Also, P. harmala at highest concentration (7.8 μg/ml) showed 68.9 and 58.6% antileishmanial activity with IC50 of 2.4 μg/ml for both of them, respectively. The SI value was 38.22 for N. sativa, 25.9 for P. harmala, 19.4 for Amphotericin B, and 16.33 for Glucantime. The results of our study indicated that N. sativa and P. harmala are effective against L. major promastigotes and amastigotes and could be consider as an alternative treatments for leishmaniosis. Therefore, it is recommended that further studies be performed to confirm the efficacy and evaluate the toxicity of the herbal extracts.