Lymphoma and lung cancer in offspring born to pregnant mice dosed with dibenzo[a,l]pyrene: the importance of in utero vs. lactational exposure.
Toxicol Appl Pharmacol
; 233(3): 454-8, 2008 Dec 15.
Article
in En
| MEDLINE
| ID: mdl-18848954
ABSTRACT
The fetus and neonate cannot be viewed as "little adults"; they are highly sensitive to toxicity from environmental chemicals. This phenomenon contributes to the fetal basis of adult disease. One example is transplacental carcinogenesis. Animal models demonstrate that environmental chemicals, to which pregnant women are daily exposed, can increase susceptibility of the offspring to cancer. It is uncertain to what degree in utero vs. lactational exposure contributes to cancer, especially for hydrophobic chemicals such as polyhalogenated biphenyls, ethers, dioxins, furans, etc., which can partition into breast milk. We developed a pregnant mouse model in which exposure to the polycyclic aromatic hydrocarbon (PAH), dibenzo[a,l]pyrene (DBP), during late gestation, produces an aggressive T-cell lymphoma in offspring between 3 and 6 months of age. Survivors exhibit multiple lung and liver (males) tumors. Here, we adopt a cross-foster design with litters born to dams treated with DBP exchanged with those born to dams treated with vehicle. Exposure to DBP in utero (about 2 days) produced significantly greater mortality than residual DBP exposure only through breast milk (3 weeks of lactation). As previously observed pups in all groups with an ahr(b-1/d) ("responsive") genotype were more susceptible to lymphoma mortality than ahr(d/d) ("non-responsive") siblings. At termination of the study at 10 months, mice exposed in utero also had greater lung tumor multiplicity than mice exposed only during lactation. Our results demonstrate that short exposure to DBP during late gestation presents a greater risk to offspring than exposure to this very hydrophobic PAH following 3 weeks of nursing.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Prenatal Exposure Delayed Effects
/
Benzopyrenes
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Lactation
/
Carcinogens, Environmental
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Lymphoma, T-Cell
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Maternal Exposure
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Lung Neoplasms
Limits:
Animals
/
Pregnancy
Language:
En
Journal:
Toxicol Appl Pharmacol
Year:
2008
Document type:
Article
Affiliation country:
Estados Unidos