ABSTRACT
Foram utilizados 182 camundongos machos, isogênicos, da linhagem C57BL/6 inoculados na orelha direita com 3,0 x 10(6) formas promastigotas da cepa MHOM/BR/PH8 de Leishmania (Leishmania) amazonensis. Os animais foram separados em três grupos: 1) 52 animais tratados com mefloquina (16mg/kg/dia/l0 dias), 2) 52 animais tratados com aminosidina [Paramomicina ©] (20mg/kg/dia/20 dias), 3) 78 animais controles, näo manipulados. Vinte e seis animais de cada grupo tratado foram sacrificados nove e quinze semanas após a inoculaçäo. Animais do grupo controle foram sacrificados na sexta, nona e décima quinta semanas após a inoculaçäo. Ao final do tratamento, em relaçäo à curva de peso da orelhas, somente nos animais tratados com aminosidina, houve nítida reduçäo do peso em comparaçäo com grupo controle. Na histopatologia verificou-se: a) näo houve diferença entre o grupo tratado com mefloquina e o grupo controle; o grupo tratado com aminosidina, ao final do tratamento, teve menor infiltraçäo por macrófagos vacuolizados; b) as avaliaçöes da extensäo das áreas de necrcose e do nível da fibrose tecidual näo mostraram diferenças entre os grupos tratados. Os animais do grupo controle apresentaram fibrose mais acentuada, seis semanas após o fim do tratamento. Pode-se concluir que ocorreu efeito terapêutico reduzido com a mefloquina e houve significativa melhora com a aminosidina. Entretanto, em todos os grupos as lesöes näo chegaram a curar
Subject(s)
Animals , Leishmaniasis, Cutaneous/drug therapy , Mefloquine , Paromomycin , Mice, Inbred Strains , Disease Models, Animal , Leishmania mexicanaABSTRACT
In the animal model of leishmaniasis caused by Leishmania (Leishmania) amazonensis there is a complex mechanism of the host-parasite interaction. The present study was performed to interfere with the inflammatory reaction to the parasites, through immune modulation. Female C5BL/6 isogenic mice were used, some of which were inoculated on the right ear and others on the right footpad with 3.10(6) stationary phase promastigotes of the MHOM/BR/PH8 strain of L. (L.) amazonensis, and were allocated in three groups: the first received pentoxifylline 8mg/kg every 12 h, since the first day; the second one received the same dose since the 40th day of infection and a control group that did not receive any treatment. All the ears excised were analyzed to determine the variation in weight between both ears and for histopathological analyses. A quantification of the parasites was done using the limiting dilution assay. A significant reduction of the number of parasites, was observed among the animals treated which had an accordingly significant reduction on the weight of the ears. Pentoxifylline reduced the macrophages propensity to vacuolation and induced a more effective destruction of the parasites by these cells. Moreover, the group that began the treatment later did not show the same effectiveness.