Exploring EGCG for Leishmaniasis: A Natural Strategy for Neglected Disease Intervention

Neglected tropical diseases (NTDs) primarily affect populations in economically disadvantaged regions globally, yet they remain underfunded and understudied. Leishmaniasis, an infection caused by parasites and transmitted by vectors, originates from protozoa in the Leishmania family, and affects 700 000 to a million new cases yearly. Despite its significant health burden and potentially fatal consequences, research into new treatments remains minimal. Current treatments like pentavalent antimonials, amphotericin B, and miltefosine have considerable side effects, high costs, lengthy treatment periods, and face drug resistance. These limited therapeutic options emphasize the need for safer, more effective treatments accessible in resource-constrained settings. Epigallocatechin gallate (EGCG), a polyphenolic compound from green tea (Camellia sinensis), shows promise as an antileishmanial agent. It disrupts the parasite's redox balance through the production of reactive oxygen species (ROS), inhibits growth, and enhances immune responses. However, poor bioavailability and rapid metabolism limit its clinical use; nanoformulations may improve its effectiveness. This review highlights the mechanism of action of EGCG against Leishmania parasites, examining its impact on parasite metabolism and cellular processes. It also explores various preclinical studies, therapeutic limitations and challenges, as well as advancements in drug delivery of EGCG for treating leishmaniasis.