Journal Article

Effects of dairy products on heterocyclic aromatic amine-induced rat colon carcinogenesis

Emmanuelle Tavan, Chantal Cayuela, Jean-Michel Antoine, Germain Trugnan, Chantal Chaugier and Pierrette Cassand

in Carcinogenesis

Volume 23, issue 3, pages 477-483
Published in print March 2002 | ISSN: 0143-3334
Published online March 2002 | e-ISSN: 1460-2180 | DOI: http://dx.doi.org/10.1093/carcin/23.3.477
Effects of dairy products on heterocyclic aromatic amine-induced rat colon carcinogenesis

More Like This

Show all results sharing this subject:

  • Clinical Cytogenetics and Molecular Genetics

GO

Show Summary Details

Preview

Heterocyclic aromatic amines (HAA) are initiating agents of colon carcinogenesis in animals and are suspected in the aetiology of human colon cancer. In the context of prevention, it seems interesting to test possible protective compounds, such as fermented milk, against HAA food carcinogens. Male F344 rats were used in a model of HAA-induced colon carcinogenesis. The HAA, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) (ratio 1:1:1) were administered in food for a 7 week induction period, with a cumulative dose of 250 mg of the HAA, per kg body weight. Four different diets were given to four rat groups: supplemented with 20% water, 30% non-fermented milk, 30% Bifidobacterium animalis DN-173 010 fermented milk and 30% Streptococcus thermophilus DN-001 158 fermented milk. Fecal mutagenicity was quantified during the induction period. At the end of the treatment, DNA lesion levels were determined in the liver and colon using the number of 8-oxo-7,8-dihydro-2′desoxyguanosine (8-oxodGuo) oxidized bases, `3D Test' and comet assay. The metabolic activity of hepatic and colon cytochrome P450 (CYP450) 1A1 and 1A2 was also evaluated. Aberrant colon crypts were scored, 8 weeks after the last HAA treatment. The results showed that dairy products decreased the incidence of aberrant crypts in rats: 66% inhibition with the milk-supplemented diet, 96% inhibition with the B.animalis fermented milk-supplemented diet and 93% inhibition with the S.thermophilus fermented milk-supplemented diet. Intermediate biomarkers showed that there was a decrease in HAA metabolism, fecal mutagenicity and colon DNA lesions. These results demonstrate the early protective effect of milk in the carcinogenesis process. This effect being more pronounced in the case of milk fermented by lactic acid bacteria.

Keywords: ACF, aberrant crypt foci;; CYP, cytochrome P450;; EROD, ethoxyresorufin deethylase;; HAA, heterocyclic aromatic amines;; IQ, 2-amino-3-methylimidazo[ 4,5-f]quinoline;; LAB, lactic acid bacteria;; MeIQ, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline;; MROD, methoxyresorufin deethylase;; 8-oxodGuo, 8-oxo-7,8-dihydro-2′desoxyguanosine;; PhIP, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine;; SD, standard deviation.

Journal Article.  6030 words.  Illustrated.

Subjects: Clinical Cytogenetics and Molecular Genetics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.