Leishmanicidal and Cytotoxic Activity of Algerian Medicinal Plants on Leishmania major and Leishmania infantum

Abstract

Introduction: Leishmaniasis is a severe disease that presents a real public health problem worldwide. Antileishmanial therapy remains expensive with intolerable side effects; therefore, it is essential to develop tolerable antileishmanial medications with a selective efficacy. Methods: In this study, the leishmanicidal activities of seven Algerian plant extracts, selected based on either ethnobotanical or chemotaxonomical data, were screened for their antileishmanial activity against promastigotes and amastigotes of cutaneous leishmaniasis agent Leishmania major (MON 25), and visceral leishmaniasis agent Leishmania infantum (MON 1). The cytotoxic activity against human monocytes THP1 was also determined. Results: In both species, amastigotes showed more sensitivity to the extracts than promastigotes. Erica arborea flower (IC50=43,98 𝜇g/mL), Marrubium vulgare leaves (IC50=45,84 𝜇g/mL) and Artemisia herba-alba Asso aerial parts (IC50=55,21 𝜇g/mL) had an almost similar inhibitory effect on L. major promastigote. Marrubium vulgare leaves (IC50=35,63 𝜇g/mL) was most effective against L. infantum promastigotes. Besides, these extracts exhibited low selectivity indices. The best results were obtained with M. vulgare on both L. major and L. infantum promastigotes (IC50s of 45,84 µg/ml and 35,63 µg/ml), and amastigotes (IC50s of 32,15 µg/ml and 18,64 µg/ml). The selectivity index was above two (2.34 for L. major and 3.01 for L. infantum), calculated based on the acceptable cytotoxic effect of M. vulgare on human macrophage cell line (CC50=107,45 µg/ml). Conclusion: Out of the seven methanol extracts tested against promastigotes of L. major and L. infantum, three showed promising activity with potent leishmanicidal effect and acceptable selectivity indices on L. major and L. infantum.

Keywords

• leishmanicidal effect
• medicinal plant
• algeria
• leishmaniasis.