METHANOLIC BARK EXTRACT OF Sterculia villosa ATTENUATE THE INTRACELLULAR LEISHMANIAL LOAD THROUGH NITRIC OXIDE GENERATION AND IMMUNOMODULATION

Antu Das, Junaid Jibran Jawed, Manash C Das, Akshay Daware, Chinmoy Ghosh, Shukdeb Acharjee, Surajit Bhattacharjee*

ABSTRACT

Visceral leishmaniasis is an immunosuppressive disease caused by the protozoan parasite Leishmania donovani. Visceral leishmaniasis affects millions of people all over the world, especially in subtropical countries. Presently available drugs against visceral leishmaniasis are restricted due to their higher toxicity. This condition further aggravated due to the development of resistance of the parasites against the available drugs. Nowadays several ethnobotanical plant extract are in use for treatment of the protozoan diseases. Sterculia villosa is an ethnomedicinal plant and possess antimicrobial, antiprotozoal property. In the present study methanolic bark extract of Sterculia villosa (SVE) was prepared to evaluate its antileishmanial and immunomodulatory activity. To evaluate its antileishmanial study, intracellular parasitic burden, nitric oxide (NO) generation and cytokine production was studied in L. donovani infected murine peritoneal macrophages. It was observed that SVE inhibited the intracellular parasitic load in the murine peritoneal macrophages and IC50 dose was found to be 50 μg/mL. It was also observed that SVE induces killing of intracellular parasite by up regulating pro-inflammatory and down regulating anti-inflammatory cytokine release. The present study explores that SVE at IC50 dose can induce parasite killing through modulation of cytokine expression and NO generation in comparison with un-treated infected macrophages.

Keywords: Leishmania donovani, SVE, amastigotes, nitric oxide, cytokines.