Anti-leishmanial potentials of Euphorbia wallichii root extracts and their effects on membrane permeability and apoptosis

Leishmaniasis is a neglected tropical disease effecting millions of people around the globe especially in developing and under developed countries. The disease is reported to be caused by a protozoan of the genus Leishmania whereas sand-fly of genus Lutzomyia or phlebotomus are main source of transmission. Three types of leishmaniasis are known till now i.e. cutaneous, Mucocutaneous and visceral leishmaniasis. Currently there is no vaccines available to treat any of the 3 types of this disease and the available drugs are highly associated with side effects like (problem in oral administration, trouble in intestinal regions, joints get rigid/stiff). Therefore, the world is now looking towards plants and plant products for the possible solution of leishmaniasis. In present project, we screened various fractions (N-Hexane, Ethyl Acetate, Chloroform and Water) of E. wallichii root extract for potential anti-leishmanial activity, its possible mechanism of action and for the presence of biologically active phytochemicals. Ethyl Acetate (EWEA) and Water (EWAQ) showed high antileishmanial potentials with IC50 value of 6.6 mg/mL and 11.3 mg/mL against promastigote and 9 mg/mL and 13 mg/mL against amastigotes form of Leishmania tropica respectively. On investigation of cytotoxicity, membrane permeability, Apoptosis and ROS generation assays, our results confirmed that all the four fractions of E. wallichii root extract bears no cytotoxic effect to human erythrocytes at lower doses. Whereas EWEA and EWAQ were able to induce membrane polarization and apoptotic death without any persistent reactive oxygen species generation in leishmanial cells. Results from different assays showed that this plant has high anti-leishmnaial potentials by killing leishmanial cells via membrane damage and apoptosis. Phytochemical investigations of the same fractions have further confirmed the presence of high quantity of tannins and saponins which may be involved in conferring membrane permeability and hence death to parasite. Therefore, further investigation like in-vivo testing and isolation of the potent anti-leishmanial compound/s are highly recommended for drug development and future treatment of leishmaniasis.

Keywords:

Anti-leishmanial , apoptosis , Euphorbia wallichii and membrane permeability