In vitro evaluation of the leishmanicidal potential of selected plant-derived extracts against Leishmania (Leishmania) amazonensis
- International Journal of Complementary & Alternative Medicine
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Julia M Souza,1 Ana Carolina BB Candido,1 Mariana C Pagotti,1 Herbert J Dias,2 Gabriela P Aguiar,1 Andréia T Arantes,3 Wilson R Cunha,1 Milton Groppo,4 Antônio EM Crotti,2 Renato LT Parreira,1 Jean A Bernatchez,5 Lizandra G Magalhãesa1
Abstract
Background: Leishmaniasis is a potentially fatal, neglected parasitic disease caused by different species of Leishmania sp. Natural products, especially from plants; represent a rich source for the screening of potential antiparasitic compounds.
Purpose and study design: In this study, we evaluated the leishmanicidal activity of thirteen plant extracts against the parasite Leishmania (Leishmania) amazonensis in vitro, the cytotoxic and hemolytic activity. The extracts with activity against the parasite, was determined the chemical constituents.
Results: The hexane extracts of Bidens sulphurea and Plectranthus neochilus were the most effective extracts against promastigote forms at 24h and 48h. The EC50 (50% effective concentration) value obtained for these extracts against promastigote forms were calculated to be 84.26µg/mL and 46.32µg/mL in 24h, respectively. The EC50 values against intracellular amastigotes were higher than 100µg/mL after 48h of incubation for both extracts. Regarding cytotoxicity in peritoneal macrophages, extracts of B. sulphurea showed CC50 values (cytotoxicity concentration of 50% of cells) of 103.9 and 80.30µg/mL at 24 and 48h, respectively, whereas the CC50 values for the P. neochilus extract were 66.95 and 34.39µg/mL at 24 and 48h, respectively. The extracts showed no significant hemolysis at the concentrations evaluated, and the CH50 values were higher than 100µg/mL. The chemical constituent of the hexane extracts of B. sulphurea and P. neochilus and their activity against L. amazonensis has not been previously described.
Conclusion: Despite the unsatisfactory results against amastigotes forms, this study shows extracts obtained from botanical sources merit further study for their leishmanicidal properties.
Keywords
Leishmania (Leishmania) amazonensis, natural products, hexane plant extracts, leishmanicidal activity, VL, visceral leishmaniasis, CL, cutaneous leishmaniasis, GC, gas chromatography, MS, mass spectrometry, FBS, fetal bovine serum, DMSO, dimethyl sulfoxide, EC50, 50% effective concentration, CC50, 50% cytotoxic concentration, HC50, 50% hemolytic concentration, SD, standard deviation, SI, selectivity index
