Avaliação do efeito imunomodulador do extrato aquoso de Agaricus blazei e sua relação com a translocação bacteriana em modelo animal

• Ano de defesa: 2007
• Autor(a) principal: Fantuzzi, Elisabete
• Orientador(a): Vanetti, Maria Cristina Dantas
• Banca de defesa: Matta, Sérgio Luis Pinto da , Paula, Sérgio Oliveira de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Microbiologia Agrícola
• Departamento: Associações micorrízicas; Bactérias láticas e probióticos; Biologia molecular de fungos de interesse
• País: BR
• Palavras-chave em Português: Imunomodulador; Agaricus blazei; Translocação bacteriana
• Palavras-chave em Inglês: Immunomudulators; Agaricus blazei; Bacterial translocation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::MICROBIOLOGIA AGRICOLA
• Link de acesso: http://locus.ufv.br/handle/123456789/1572

The goal of this work was to investigate the immunomodulator effects of Agaricus blazei water extract and its relation with the translocation of autochthones bacteria as well as of Salmonella enterica Typhimurium (106 CFU mL -1), in animal model. A. blazei water extract was administrated ad libitum and by intragastric gavage in mice of six to seven weeks, two weeks before the first dose of cyclosphosphamide and until the 23th day of experiment. In the experiment using S. enterica Typhimurium to challenge the animals, A. blazei water extract was administrated daily for 16 days before the challenge and until the 22th day, when the animals were sacrificed. It was not verified significant difference (P>0.05) in the weight gain (g) of the animals among the tested groups during the weekly evaluation; however it was observed a similar reduction in the weight of animals submitted to the treatments of immunodeppressive groups with cyclosphosphamide 200 mg kg -1 in the last week of evaluation, independently if A. blazei water extract was administrated or not ad libitum and by intragastric gavage. It was not observed translocation of autochthones Gram-negative bacteria in none of the evaluated animals, in the experiment involving immunodeppression. The immunodeppressed animals exhibited spleenic index lower than the control animals, however it was not verified significant difference (P>0.05) among the groups treated or not with A. blazei water extract. It was not observed differences in the secretion of IgAs in the thin intestine as well as in the serum secretions of TNF-α, IFN-γ and IL-10 of the animals submitted to the treatment with A. blazei water extract independent if they were immunodeppressed or not. The administration of cyclosphosphamide did not change the histology of ileum and liver compared to the control samples, however, in the spleen of the immunodeppressed animals evaluated, it was observed a reduction of the lymphoid follicles and lymphocytic depletion, and the administration of A. blazei water extract did not change this aspect. In the experiment involving microbial challenge, the values of spleenic index of the defied animals with S. enterica Typhimurium were not different (P>0.05) from that found in animals not defied or in animals witch received the extract of A. blazei. The secretion of IgAs in the small intestine of mice as well as the secretions of TNF-α, IFN-γ and IL-10 were not affected (P>0.05) by the administration of A. blazei water extract or by microbial defy. Typical colonies of S. enterica Typhimurium were recovered from liver, spleen and mesenteric linfonods (MLNs) of the defied animals in the analyses conduced in the fifth day after inoculation of 106 CFU mL -1 per animal. Nevertheless, significant difference (P>0.05) did not occur in the translocation observed in the defied animals of groups treated or not treated with A. blazei water extract. In the defied group with S. enterica Typhimurium the histopatologic analyses showed small and diffuse focuses of mixed inflammatory infiltrates in the hepatic parenchyma compatible with translocation. The spleen of defied animals also exhibited discreet reactional hyperplasia, with discreet increase lymphoid follicles and discrete increase of the germinal centers. The treatment with water extract did not modify the spleen and liver reply in the defied group. Similar to the group witch received only water and intragastric gavage with Salmonella, the ileum of treated animals with A. blazei water extract did not exhibit significant changes. The water extract of A. blazei used in this study, therefore, did not influence none of the selected variable to analyze its effect immunomodulators in vivo.