Review on natural products as an alternative to contemporary anti-leishmanial therapeutics

Abstract

Leishmaniasis is a vector-borne protozoan disease caused by an intracellular parasite which globally affects 350 million people. This infectious disease mainly affects undeveloped and developing countries across the world. Chemotherapeutic therapies mainly depend on pentavalent antimonials, miltefosine, stibogluconate, amphotericin B and paromomycin. However, these medications exhibit several side-effects including toxicity, cost and emerging drug resistance and this has proved to be an obstacle in the eradication of the disease. Considering the alarming drug resistance, there is an urgent need for a novel and potentially effective approach against leishmaniasis. In the course of identification of new therapies, plant-based compounds were found to be an alternative that can either be used directly or with structural modifications. Various plants have been known for ages to be the source of phytochemicals with high medicinal values. These phytochemicals have been extracted by different techniques and have shown efficacy against numerous diseases. This review study concentrates on the application of various plant source drugs and their modified analogs for the treatment of Leishmania. These natural compounds have also been tagged with nanoparticles for better delivery, efficacy, and bioavailability. These modified nanoformulations have the potential to become a better drug delivery system in the future. Thus, this review provides an overview of the current chemotherapeutic therapies, plant-based therapies and the application of nanotechnology for better efficacy.