RESUMO
The bioassay-guided phytochemical investigation of the leaf extract of Serjania yucatanensis, a woody climbing plant endemic to the Yucatan peninsula, led to the identification of a mixture of a triterpene [lup-20(29)-en-3-one] and an oxygenated sesquiterpene (ß-caryophyllene oxide), as that responsible for the originally detected trypanocidal activity in the organic crude extract. Results showed that the mixture of lup-20(29)-en-3-one and ß-caryophyllene oxide is active against trypomastigotes of Trypanosoma cruzi (IC(50) =80.3 µg/mL) and inhibits the egress of trypomastigotes from infected Vero cells (when tested at 100 µg/mL) without being cytotoxic.
Assuntos
Antiprotozoários/farmacologia , Extratos Vegetais/farmacologia , Sapindaceae/química , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Bioensaio , Chlorocebus aethiops , Concentração Inibidora 50 , Testes de Sensibilidade Parasitária , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Sesquiterpenos/análise , Sesquiterpenos/farmacologia , Triterpenos/análise , Triterpenos/farmacologia , Células VeroRESUMO
Ethanol extracts of Senna villosa, Serjania yucatanensis, Byrsonima bucidaefolia, and Bourreria pulchra were evaluated for their in vitro activity against epimastigotes and trypomastigotes of Trypanosoma cruzi. Results showed that the leaf extracts of S. yucatanensis and B. pulchra were the most active against epimastigotes (IC(100) = 100 µg/mL) and trypomastigotes of T. cruzi (95% or more reduction in the number of parasites at 100 and 50 µg/mL). However, only the leaf extract of S. yucatanensis showed significant trypanocidal activity when tested in vivo, reducing 75% of the parasitemia in infected mice at 100 mg/kg. This same extract inhibited the egress of trypomastigotes from infected cells and proved not to be cytotoxic (IC(50) = 318.8 ± 2.3 µg/mL).
