In Vitro Leishmanicidal Activities of Sesquiterpene Lactones from Tithonia diversifolia against Leishmania braziliensis Promastigotes and Amastigotes
Juliano S. de Toledo,
Sergio R. Ambrósio,
Carly H. G. Borges,
Viviane Manfrim,
Daniel G. Cerri,
Angela K. Cruz,
Fernando B. Da Costa
Affiliations
Juliano S. de Toledo
Department of Cell Biology, Molecular and Pathogenic Bioagents, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Av. Bandeirantes 3900, Monte Alegre, Ribeirão Preto, SP 14049-900, Brazil
Sergio R. Ambrósio
Center for Research in Exact and Technological Sciences, University of Franca—UNIFRAN, Franca, SP 14404-600, Brazil
Carly H. G. Borges
Center for Research in Exact and Technological Sciences, University of Franca—UNIFRAN, Franca, SP 14404-600, Brazil
Viviane Manfrim
Department of Cell Biology, Molecular and Pathogenic Bioagents, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Av. Bandeirantes 3900, Monte Alegre, Ribeirão Preto, SP 14049-900, Brazil
Daniel G. Cerri
Department of Cell Biology, Molecular and Pathogenic Bioagents, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Av. Bandeirantes 3900, Monte Alegre, Ribeirão Preto, SP 14049-900, Brazil
Angela K. Cruz
Department of Cell Biology, Molecular and Pathogenic Bioagents, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Av. Bandeirantes 3900, Monte Alegre, Ribeirão Preto, SP 14049-900, Brazil
Fernando B. Da Costa
AsterBioChem Research Team, Laboratory of Pharmacognosy, Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, USP, Av. do Café s/n, Ribeirão Preto, SP 14040-903, Brazil
Natural compounds represent a rich and promising source of novel, biologically active chemical entities for treating leishmaniasis. Sesquiterpene lactones are a recognized class of terpenoids with a wide spectrum of biological activities, including activity against Leishmania spp. In this work, a sesquiterpene lactone-rich preparation—a leaf rinse extract (LRE) from Tithonia diversifolia—was tested against promastigote forms of L. braziliensis. The results revealed that the LRE is a rich source of potent leishmanicidal compounds, with an LD50 value 1.5 ± 0.50 µg·mL−1. Therefore, eight sesquiterpene lactones from the LRE were initially investigated against promastigote forms of L. braziliensis. One of them did not present any significant leishmanicidal effect (LD50 > 50 µg·mL−1). Another had a cytotoxic effect against macrophages (4.5 µg·mL−1). The five leishmanicidal compounds with the highest level of selectivity were further evaluated against intracellular parasites (amastigotes) using peritoneal macrophages. Tirotundin 3-O-methyl ether, tagitinin F, and a guaianolide reduced the internalization of parasites after 48 h, in comparison with the negative control. This is the first report on sesquiterpene lactones that have potent leishmanicidal effects on both developmental stages of L. braziliensis.