RESUMEN
A leishmaniose é considerada uma importante causa de morbidade e mortalidade a nível mundial, principalmente nos países tropicais. As formas cutânea e mucocutânea são causadas, entre outras espécies, por Leishmania braziliensis. Na procura de compostos leishmanicidas de origem natural, foi estudada a atividade da mistura de alcalóides de Ervatamia coronaria (Apocynaceae) contra amastigotas de L. braziliensis em 6 concentrações diferentes (1, 10, 20, 25, 50 e 100 µg/mL). Foram tratados macrófagos de ratos da linha J774, infectados com promastigotas de L. braziliensis, com a mistura de alcalóides 1 hora após-infecção e diariamente por 3 dias sem mudança de meio. As experiências de citotoxicidade foram efetuadas sobre os macrófagos com azul tripam. Todos os cultivos foram feitos de forma triplicada e os grupos de controle não foram submetidos à mistura de alcalóides. Foi obtido que o composto adicionado exerce atividade doses/dependente sobre a parasita. No entanto, as concentrações mais altas (50 e 100 µg/mL), adicionado durante 3 dias, mostraram os maiores índices de infecção, provavelmente devido a diminuição no número de macrófagos, sobre os quais não foi observado efeito tóxico do tratamento durante 24 horas DL50/24h = 233,52 µg/mL. Os resultados dessa pesquisa revelaram uma nova atividade farmacológica de alcalóides da espécie Ervatamia coronaria sobre a forma amastigota de Leishmania braziliensis, com IC50 = 2,6 e 12,4 µg/mL sem mostrar toxicidade sobre a célula hospedeira.
Leishmaniasis, caused by Leishmania sp., is one of the mean reason of considerable mortality and morbidity throughout the world, especially in the tropics. Cutaneous and mucocutaneous manifestations are caused by Leishmania braziliensis, and the cutaneous form is the most common one in Colombia. In the search for antileishmanial compounds from natural sources, we studied the alkaloids mixture from Ervatamia coronaria against L. braziliensis at six different concentrations (1.0, 10, 20, 25, 50 and 100 µg/mL). Macrophages J774 infected with L. braziliensis were treated with alkaloids one hour, and once a day for three days, after parasitic infection and preserving the same culture medium. Cytotoxicity with trypan blue was undertaken in macrophages J774 by using the same concentrations. Three different cultures samples were carried out. As a control we used medium alone. The alkaloids mix showed a dose/dependent activity on amastigote, but by increasing concentrations from 50 to 100 µg/mL for three days, we saw a high index of infection, probably caused by cellular death. We did not see any toxic effect on macrophages J774 at 100 µg/mL, LD50/24h= 233.52 µg/mL. These results revealed a novel pharmacological activity of alkaloids from E. coronaria against amastigotes of L. braziliensis IC50 = 2.6 and 12.4 µg/mL without toxicity on host cells.
RESUMEN
Los programas de doctorado son relativamente recientes en Colombia y sólo se articularon formalmente como parte de la estructura de la educación superior con la Ley 30 de 1992. Aunque esta modalidad de estudio posgradual, que otorga el más alto título educativo, se ha venido regla-mentando en nuestro país (decretos 836 de 1994,2791 de 1994, 1475 de 1996, 2566 de 2003 y1001 de 2006), aún no ha logrado alcanzar una cobertura significativa en las ofertas académicas que promueven la mayoría de las universidades tanto públicas como privadas. El hecho de que en relación con el resto del mundo en nuestro medio llegamos a desarrollar tardíamente este tipo de formación educativa noes algo fortuito: está en concordancia con las características sociales, económicas, culturales y políticas de la nación colombiana.
Doctoral programs are relatively recent in Colombia and were only formally articulated as part of the structure of higher education with Law 30 of 1992. Although this modality of postgraduate study, which grants the highest educational degree, has been regulated in our country (decrees 836 of 1994, 2791 of 1994, 1475 of 1996, 2566 of 2003 and 1001 of 2006), it has not yet achieved significant coverage in the academic offerings promoted by most public and private universities. The fact that in relation to the rest of the world in our environment we are late in developing this type of educational training is not fortuitous: it is in accordance with the social, economic, cultural and political characteristics of the Colombian nation.
Asunto(s)
Humanos , Educación de Postgrado , Universidades , Colombia , Universidades , PolíticasRESUMEN
Primary cell cultures were obtained from eggs of Anopheles albimanus and Aedes taeniorhynchus mosquitoes, vectors of human malaria and of Venezuelan equine encephalitis virus, respectively. The cellular growth of the An. albimanus cells began four weeks after explanting the embryonic tissues in MK/VP12 medium, supplemented with 15 por cento fetal bovine serum. The culture showed heterogeneous cellular morphology. With regard to the Ae. taeniorhynchus culture, growth occurred three weeks after initiating the culture in MM/VP12 medium. The majority of cells were small and round. Karyotypes were examined in the latter species.