Mahdi Aghaei
Farhood Alizadegan
Yosra Raziani
Githa Kishore
Massumeh Saadatmand
Suja Ajoy Kumar

Introduction: Leishmaniasis caused by Leishmania spp. is observed in most parts of the world. Although, glucantime, a pentavalent antimony compound, and other synthetic drugs are broadly applied for leishmaniasis therapy; however, the use of these synthetic agents has some limitations. Hence, this study was designed to assess the inhibiting effects of ۷-hydroxy۴′-methoxyisoflavone (۷HMI) against promastigote and amastigote stages of Leishmania major in vitro. Methods: The MTT assay was applied to study the antileishmanial activity of ۷HMI against promastigotes and its cytotoxicity effects on macrophage cells. The nitric oxide (NO) produced by the treated macrophage cells with ۷HMI was also assessed. Results: ۷HMI considerably (P<۰.۰۵) inhibited the growth rate of promastigotes and amastigotes stages. The ۵۰% inhibitory concentrations of ۷HMI and glucantim were ۱۱.۳ and ۱۵.۴ µg/mL for promastigote and amastigote, respectively. ۷HMI, especially at ۱/۳ IC۵۰ and ۱/۲ IC۵۰ concentrations, considerably triggered the NO release. Conclusion: The current research findings reported the favorable antileishmanial effects of ۷HMI against L. major with possible mechanisms such as reducing the infectivity rate of macrophage cells and provoking NO creation. Nevertheless, more research must be performed to clear its efficacy in animal model and then in human.