Polybrominated diphenyl ether (PBDE)-induced alterations in vitamin A and thyroid hormone concentrations in the rat during lactation and early postnatal development.
In experimental animals fed standard laboratory diets, penta-BDE mixtures can decrease circulating thyroid hormone and liver vitamin A concentrations. A substantial number of pregnant women and their children have marginal vitamin A status, potentially increasing their risk of adverse effects to penta-BDE exposure. The current study investigated the effects of maternal gestational and lactational penta-BDE exposure on thyroid hormone and vitamin A homeostasis in rats of sufficient vitamin A (VAS) or marginal vitamin A (VAM) status and their offspring. Dams were administered daily oral doses of 18 mg/kg DE-71 (a penta-BDE mixture) or a corn oil vehicle from gestation day 6 through lactation day (LD) 18. Thyroid hormone and vitamin A homeostasis were assessed in plasma and tissues of LD 19 dams and postnatal day (PND) 12, 18, and 31 pups. DE-71 exposure induced hepatomegaly in VAS and VAM pups at all timepoints and increased testes weights at PND 31. While liver vitamin A concentrations were low in DE-71 treated dams and pups, plasma retinol concentrations and plasma retinol binding protein levels were only low in VAM animals exposed to DE-71. DE-71 exposure lowered plasma thyroxine concentrations in VAS and VAM dams and pups. Plasma thyroid stimulating hormone concentrations were high in VAM dams exposed to DE-71, suggesting that marginal vitamin A status enhances the susceptibility to thyroid hormone axis disruption by DE-71. These results support the concept that marginal vitamin A status in pregnant women may increase the risk for PBDE-induced disruptions in vitamin A and thyroid hormone homeostasis.
Department of Nutrition, University of California-Davis, Davis, CA 95616, USA.
Robert G
RG
Ellis-Hutchings
Gary N
GN
Cherr
Lynn A
LA
Hanna
Carl L
CL
Keen
D000818:Animals; D000831:Animals, Newborn; D000833:Animals, Suckling / Q000097:blood*; D005260:Female; D005411:Flame Retardants / Q000633:toxicity*; D048788:Growth and Development / Q000187:drug effects; D055768:Halogenated Diphenyl Ethers; D006706:Homeostasis / Q000187:drug effects; D007774:Lactation / Q000097:blood; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D010647:Phenyl Ethers / Q000633:toxicity*; D011075:Polybrominated Biphenyls / Q000633:toxicity*; D011247:Pregnancy; D051381:Rats; D012098:Reproduction / Q000187:drug effects; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood; D014801:Vitamin A / Q000097:blood*
D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D010647:Phenyl Ethers; D011075:Polybrominated Biphenyls; D013963:Thyroid Hormones; D014801:Vitamin A; C086401:pentabromodiphenyl ether; D013972:Thyrotropin