RESUMO
The chemical study of Eugenia protenta McVaugh extracts performed by classical and high-performance liquid chromatography techniques and spectral methods has led to the identification of known triterpenoids, flavonoids and an acetophenone derivative (dimethylxanthoxylin). The effect of dimethylxanthoxylin on Leishmania (Leishmania) amazonensis was evaluated against the promastigotes forms after 96 h of treatment. Dimethylxanthoxylin reduced 57 and 59% of the promastigotes growth when treated with 50 and 100 µg/mL solutions, respectively (IC50 117.35 µg/mL or 52.3 µM). Cytotoxicity experiments using MTT assays showed that this substance did not promote cell death after 24 h of treatment. Dimethylxanthoxylin was active on the promastigotes and could be a promising agent for treating leishmaniasis.
Assuntos
Acetofenonas/farmacologia , Antiprotozoários/farmacologia , Eugenia/química , Leishmania/efeitos dos fármacos , Acetofenonas/isolamento & purificação , Animais , Antiprotozoários/isolamento & purificação , Células Cultivadas , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/químicaRESUMO
The effects of the Securinega alkaloid (+)-phyllanthidine on Leishmania (L.) amazonensis and the first chemical investigation of Margaritaria nobilis L.f. (Phyllanthaceae) are described. Treating the parasites with this alkaloid caused a dose-dependent reduction in promastigote growth of 67.68% (IC50 82.37 µg/mL or 353 µM) and in amastigote growth of 83.96% (IC50 49.11 µg/mL or 210 µM), together with ultrastructural alterations in the promastigotes. No cytotoxic effect was detected in mammalian cells (CC50 1727.48 µg/mL or CC50 5268 µM). Classical chromatographic techniques and spectral methods led to the isolation and identification of betulinic acid, kaempferol, corilagin, gallic acid and its methyl ester, besides (+)-phyllanthidine from M. nobilis leaves and stems. Margaritaria nobilis is another source of the small group of Securinega alkaloids, together with other Phyllanthaceae (Euphorbiaceae s.l.) species. The low toxicity to macrophages and the effects against promastigotes and amastigotes are suggestive that (+)-phyllanthidine could be a promising antileishmanial agent for treating cutaneous leishmaniasis.
Assuntos
Antiprotozoários/farmacologia , Euphorbiaceae/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Alcaloides/isolamento & purificação , Animais , Antiprotozoários/isolamento & purificação , Relação Dose-Resposta a Droga , Ácido Gálico/isolamento & purificação , Glucosídeos/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Taninos Hidrolisáveis/isolamento & purificação , Concentração Inibidora 50 , Quempferóis/isolamento & purificação , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/ultraestrutura , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Triterpenos Pentacíclicos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Cultura Primária de Células , Triterpenos/isolamento & purificação , Ácido BetulínicoRESUMO
The chemical study of Aparisthmium cordatum (Euphorbiaceae) led to the isolation of tannins, together with the alkaloid ricinine and other common compounds. The composition of A. cordatum is similar to most of the Alchornea species, from the same subtribe, except for the occurrence of ricinine. This study rectifies the first investigations published for A. cordatum that were conducted with Croton palanostigma.