RESUMO
The difficulties encountered and the numerous side effects present in the treatment of cutaneous leishmaniasis have encouraged the research for new compounds that can complement or replace existing treatment. The growing scientific interest in the study of plants, which are already used in folk remedies, has led our group to test Endlicheria bracteolata essential oil against Leishmania amazonensis. Several species of the Lauraceae family, or their compounds, have relevant antiprotozoal activities Therefore, the biological potential on L. amazonensis forms from the essential oil of Endlicheria bracteolata leaves was verified for the first time in that work. The antileishmanial activity was evaluated against promastigotes and intracellular amastigotes, and cytotoxicity were performed with J774.G8, which were incubated with different concentrations of E. bracteolata essential oil. Transmission electron microscopy and flow cytometry were performed with E. bracteolata essential oil IC50. Promastigote forms showed E. bracteolata essential oil IC50 of 7.945 ± 1.285 µg/mL (24 h) and 6.186 ± 1.226 µg/mL (48 h), while for intracellular amastigote forms it was 3.546 ± 1.184 µg/mL (24 h). The CC50 was 15.14 ± 0.090 µg/mL showing that E. bracteolata essential oil is less toxic to macrophages than to parasites. Transmission electron microscopy showed that E. bracteolata essential oil treatment is capable of inducing mitochondrial damage to promastigote and intracellular amastigote forms, while flow cytometry showed ΔÑ°m disruption in treated parasites. These results could bring about new possibilities to develop products based on E. bracteolata essential oil to treat cutaneous leishmaniasis, especially for people who cannot receive the conventional therapy.
Assuntos
Antiprotozoários/farmacologia , Leishmania mexicana/química , Leishmania/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Antiprotozoários/química , Cromatografia Gasosa-Espectrometria de Massas , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Macrófagos/patologia , Macrófagos/ultraestrutura , Camundongos , Óleos Voláteis/química , Testes de Sensibilidade ParasitáriaRESUMO
Essential oil of Cymbopogon citratus collected from Brazil and Cuba was tested to a chemical characterization and then was tested on the post-embryonic development of Musca domestica. The chemical composition analysis by GC-MS of the oils from Brazil/Cuba allowed the identification of 13 and 12 major constituents respectively; nine of them common to both. In the both oils, the main components were the isomers geranial and neral, which together form the compound citral. This corresponds to a total of 97.92%/Brazil and 97.69%/Cuba of the compounds identified. The monoterpene myrcene, observed only in the sample of Cuba, presented a large relative abundance (6.52%). The essential oil of C. citratus (Brazil/Cuba) was dissolved in DMSO and tested at concentrations of 5, 10, 25, 50, 75 and 100% and citral was prepared by mixing 16.8 mg with 960 µL DMSO. Both essential oils and monoterpene citral were applied topically to newly-hatched larvae (1µL/larva). The results showed a lethal concentration (LC50) of 4.25 and 3.24% for the Brazilian and Cuban essential oils, respectively. Mortalities of larval and newly-hatched larvae to adult periods were dose-dependent for the two both oils as for monoterpene citral, reaching 90%. Both essential oils and citral caused morphological changes in adult specimens.