Determination of Immunostimulatory Efficacy of Benzimidazole Derivatives Against Leishmania infantum

Abstract Leishmaniasis is a parasitic disease affecting more than 12 million people worldwide. Although the use of chemotherapeutic drugs is among the current treatment methods, it is emphasized that the limitations of the drugs, their disadvantages such as insufficient safety and efficacy, the disease being endemic, and the need to develop drugs for this disease. In this study, in vitro anti-leishmanial activities of two benzimidazole derivatives (B1 and B2) were tested against L. infantum promastigote and amastigote for the first time. In our study, the anti-leishmanial effects of B1 and B2 on both amastigote and promastigote forms of Leishmania infantum were investigated using J774 macrophage cells. It was found that the tested compounds were not toxic to the host cell. In addition, when compared to the drug miltefosine, which is used worldwide in the treatment of leishmaniasis, it has been determined that it has a serious inhibitory effect by reducing the proliferation of promastigotes and the metabolic activities of amastigotes, and it acts at lower concentrations than miltefosine. We found that benzimidazolium derivatives (B1 and B2) used for the first time in this study were more effective on both forms of L. infantum. The obtained results showed that benzimidazolium derivatives have high anti-leishmanial potential against L. infantum, which is the cause of visceral leishmaniasis (VL), which is known to be the deadly form of leishmaniasis. It has been shown that the obtained results will help the development of safe, stable, and effective anti-leishmanial drug formulations against VL.