Influence of dietary protein intakes on the metabolism and DNA-binding of 7,12-dimethylbenz(a)anthracene (DMBA) in rat mammary epithelial cells

Journal Article · Wed Mar 05 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:7024636

Singletary, K; Milner, J

The influence of prior dietary protein intakes in rats on the ability of their isolated mammary cells to metabolize DMBA to intermediates that bind to intracellular DNA was examined. Female 40d old SD rats (30) were pair-fed isocaloric diets containing 7.5 or 15% protein (casein) for two weeks prior to sacrifice. Pooled cells were plated (0.9 mg protein) in Dulbecco's Modified Eagle's Medium containing antibiotics, insulin and 10% fetal calf serum, 1 h before adding 0.4 ..mu..g DMBA/ml. At 6 hours of incubation, cells from rats fed 15% protein metabolized 52.7% of the DMBA while those from rats fed 7.5% protein metabolized 43.7%. Extracellular water-soluble metabolites increased as dietary protein increased but accounted for only 14% of total metabolism. Binding of DMBA at 6 h to DNA from rats fed 15% protein was 19% higher than binding in rats fed 7.5% protein. These differences in binding increased with increasing doses of DMBA. The increased binding was associated with a proportional increase in both syn and anti- bay-region dihydrodiol-epoxide adducts. The bay-region syn-dihydrodiol-epoxide:deoxyadenosine adduct was the predominant adduct. Thus, increasing dietary protein intake leads to increased metabolism of DMBA and increased binding of bay-region dihydrodiol-epoxides to DNA.

• Research Organization: Univ. of Illinois, Urbana
• OSTI ID: 7024636
• Report Number(s): CONF-8604222-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:4; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADDUCTS
ANIMAL TISSUES
ANIMALS
AROMATICS
BENZANTHRACENE
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL MODELS
BODY
CONDENSED AROMATICS
DIET
DNA
DNA ADDUCTS
DOSE-RESPONSE RELATIONSHIPS
EPITHELIUM
GLANDS
HYDROCARBONS
INTAKE
KINETICS
MAMMALS
MAMMARY GLANDS
METABOLISM
METABOLITES
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RATS
REACTION KINETICS
RODENTS
TISSUES
VERTEBRATES