Potential effects of the herbicide Diuron on mammary and urinary bladder two-stage carcinogenesis in a female Swiss mouse model

Autor(es)

de Moura, Nelci Antunes ^[1] ; Grassi, Tony Fernando ^[2] ; Marchesan Rodrigues, Maria Aparecida ^[2] ; Barbisan, Luis Fernando ^{[2, 1]}

Afiliação do(s) autor(es)

^[1] UNESP Sao Paulo State Univ, Dept Morphol, Inst Biosci, BR-18618000 Botucatu, SP - Brazil

^[2] UNESP Sao Paulo State Univ, Dept Pathol, Fac Med, BR-18618000 Botucatu, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ARCHIVES OF TOXICOLOGY; v. 84, n. 2, p. 165-173, FEB 2010.
• Citações Web of Science: 9

Resumo

The potential promoting effect of Diuron was investigated in a mouse model of mammary and urinary bladder carcinogenesis induced by 7,12-dimethylbenz(a)anthracene (DMBA) and N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Four-week old female Swiss mice were allocated to five groups: Groups G1-G3 received DMBA (5 x 1.5 mg/mouse) and BBN (8 x 7.5 mg/mouse) and G4 and G5 groups received only vehicles during the first 6 weeks. At week 7, G1 and G5 groups received basal diet and G2, G3 and G4 groups were fed a diet containing Diuron at 1,250, 2,500 and 2,500 ppm, respectively, during 13 weeks. At week 20, the animals were euthanized and the gross tumors were registered. Mammary glands and urinary bladder were processed for histopathological analysis. Samples from non-tumor areas were evaluated for cell proliferation by 5-bromodeoxyuridine labeling index (BrdU-LI%) and apoptosis. Dietary treatment with Diuron at 1,250 and 2,500 ppm significantly increased BrdU-LI% (P < 0.05) and the incidence of simple/nodular urothelial hyperplasia in the urinary bladder from DMBA/BBN-initiated groups (G2 and G3 vs. G1, P < 0.02) and in the non-initiated group (G4 vs. G5, P = 0.042). Two transitional cell carcinomas were observed in the group initiated and fed Diuron 2,500 ppm (G3). In contrast, in the mammary gland, Diuron feeding for 13 weeks did not significantly alter cell proliferation and apoptosis indexes or the incidence of hyperplastic lesions or neoplasms in the DMBA/BBN-initiated groups. These findings suggest that Diuron is a promoting agent to the urinary bladder but not to the mammary gland in female Swiss mice submitted to a medium-term two-stage carcinogenesis bioassay. (AU)

• Processo FAPESP: 06/01330-0 - Carcinogênese de mama em modelo experimental de exposição gestacional, juvenil e adulta ao herbicida diuron [3(3,4-diclorofenil) 1,1, dimetil uréia] em fêmeas Sprague-Dawley
• Beneficiário: Tony Fernando Grassi
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 07/58937-7 - Efeitos do herbicida diuron sobre etapa de promocao da carcinogenese quimica da mama e bexiga em femeas da linhagem swiss.
• Beneficiário: Nelci Antunes de Moura
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica