Arquivo Brasileiro de Medicina Veterinária e Zootecnia (Oct 2006)
Efeito do miriadenolídeo isolado de Alomia myriadenia (Asteraceae) sobre o tumor de Erlich ascítico no camundongo Effect of myriadenolide isolated from Alomia myriadenia (Asteraceae) on Ehrlich tumor in its ascitic form
Abstract
Estudou-se atividade antineoplásica de um produto natural isolado de Alomia myriadenia (miriadenolídeo) no modelo do tumor de Ehrlich em camundongos. Dezoito fêmeas de camundongo Swiss foram inoculadas com 2x10(7) células viáveis de tumor de Ehrlich via intraperitoneal (0,3ml) e posteriormente distribuídas aleatoriamente em três grupos que receberam: grupo I (controle) - 0,3ml de solução de Hanks; grupo II - 31µg/kg de miriadenolídeo; e grupo III - 139µg/kg de miriadenolídeo. No oitavo dia de experimento, foram realizados exames hematológicos e perfil protéico sérico eletroforético. Coletou-se todo o líquido ascítico para avaliação do volume, aparência, pH, contagem de células viáveis e inviáveis, realização de esfregaços para contagem de células claras e escuras, leucócitos e avaliação das regiões organizadoras de nucléolos argentafins (AgNORs). Foram realizados exames macro e microscópicos do baço, fígado e rins e aspirado o conteúdo da medula óssea dos fêmures direito e esquerdo de cada animal para avaliação da relação mielóide:eritróide. Não houve diferença significativa no volume, pH, contagem de células viáveis e inviáveis entre os três grupos estudados, observando-se valores de 17,6 x 10(4) células tumorais viáveis no grupo III, 27,7 x 10(4) no grupo II e 21,1 x 10(4) no grupo I. As AgNORs apresentaram-se pequenas, com distribuição difusa e incontáveis no grupo I, e em menor quantidade no grupo III. Os animais do grupo III apresentaram a menor concentração protéica total sérica (4,7g/dl) (PAntitumoral activity of a natural product of Alomia myriadenia (myriadenolide) in Ehrlich tumor in mice was studied. Eighteen Swiss female mice were intra-peritoneal inoculated 2x10(7) viable cells of Ehrlich Tumor (0.3ml) and randomly distributed in three groups receiving via intra-peritoneal on the 3rd and 5th day post-inoculation the following treatments: group I (control) - 0.3ml Hanks solution; group II: 31µg/kg myriadenolide; and group III: 139µg/kg myriadenolide. On the eighth day of the experiment blood profile and protein serum electrophoresis were performed. All ascitic liquid was collected to evaluate the volume and pH; to observe the aspect; to count viable and no viable cells, dark and clear cells, leukocytes and nucleolar organizer regions (NORs). Macro and microscopic exams were performed and bone marrow was aspirated from right and left femurs of each animal to evaluate myeloid:erythroid ratio. It was not observed difference in volume, pH, counts viable and no viable cells in the groups, although group III showed smaller number of viable tumoral cells (17.6 x 10(4)) when compared to the group II (27.7 x 10(4)) and group I (21.1 x 10(4)). The investigation of NORs to evaluate the proliferative capacity of tumoral cells after myriadenolide treatment showed that cells were smaller, uncountable and with diffuse distribution in group I. They were in lower quantity in group III. These results suggest that myriadenolide in dose 139µg/kg (group III) delay the tumoral growing and, probably, cell proliferation. The animals of group III showed lower value of total protein (4.7g/dl) (P<0.05) when compared to animals from group II (5.3g/dl) and group I (5.1g/dl). The values of albumin were similar in all groups (2.6g/dl) and total globulin was higher (P<0.05) in group II (2.71g/dl) when compared to mean values of group III (2.11g/dl) and similar to group I (2.43g/dl). The decrease of total protein in group III occurred by globulin reduction. There was no difference in alpha and beta globulin in the three studied groups, although the immunoglobulins were higher (P<0.05) in group II (1.72g/dl) when compared to group III (1.13g/dl). These results suggest the viable number of tumoral cells in group II could cause the increase response of IgM reflecting on the final value of immunoglobulins. In relation to erythrogram and leukogram there was no statistical difference. The myeloid:erythroid ratio was higher (P<0.05) in group III (1.40) when compared to groups I (0.92) and II (0.61). Reticulocytes count were higher (P<0.05) (11.2) in group III, when compared to groups I (4.3) and II (3.6). In all groups, hepatic degeneration was observed.
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