Luís Fernando Barbisan, Clarissa Scolastici, Maristela Miyamoto, Daisy Maria Favero Salvadori, Lúcia Regina Ribeiro, Augusto Ferreira da Eira, João Lauro Viana de Camargo
Published: September 30, 2003
Genet. Mol. Res. 2 (3) : 295-308
Cite this Article:
L.Fernando Barbisan, C. Scolastici, M. Miyamoto, D.Maria Fave Salvadori, L.Regina Ribeiro, A.Ferreira da Eira, J.Lauro Vian de Camargo (2003). Effects of crude extracts of Agaricus blazei on DNA damage and on rat liver carcinogenesis induced by diethylnitrosamine. Genet. Mol. Res. 2(3): 295-308.
About the Authors
Luís Fernando Barbisan, Clarissa Scolastici, Maristela Miyamoto, Daisy Maria Favero Salvadori, Lúcia Regina Ribeiro, Augusto Ferreira da Eira, João Lauro Viana de Camargo
Corresponding author
L.F. Barbisan
E-mail: barbisan@ibb.unesp.br
ABSTRACT
The effects of crude extracts of the mushroom Agaricus blazei Murrill (Agaricaceae) on both DNA damage and placental form glutathione S-transferase (GST-P)-positive liver foci induced by diethylnitrosamine (DEN) were investigated. Six groups of adult male Wistar rats were used. For two weeks, animals of groups 3 to 6 were treated with three aqueous solutions of A. blazei (mean dry weight of solids being 1.2, 5.6, 11.5 and 11.5 mg/ml, respectively). After this period, groups 2 to 5 were given a single ip injection 200 mg/kg DEN and groups 1 and 6 were treated with 0.9% NaCl. All animals were subjected to 70% partial hepatectomy at week five and sacrificed 4, 24 and 48 h or 8 weeks after DEN or 0.9% NaCl treatments (10th week after the beginning of the experiment). The alkaline comet assay and GST-P-positive liver foci development were used to evaluate the influence of the mushroom extracts on liver cell DNA damage and on the initiation of liver carcinogenesis, respectively. Previous treatment with the highest concentration of A. blazei (11.5 mg/ml) significantly reduced DNA damage, indicating a protective effect against DEN-induced liver cytotoxicity/genotoxicity. However, the same dose of mushroom extract significantly increased the number of GST-P-positive liver foci.
Key words: DNA damage, Agaricus blazei, GST-P-positive liver foci, Hepatocarcinogenesis.