Toxic effect of PBDE-47 on thyroid development, learning, and memory, and the interaction between PBDE-47 and PCB153 that enhances toxicity in rats.

Abstract

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are widespread environmental contaminants. There are potential interactive effects between PBDEs and PCBs, as these compounds share similar structures. The developmental neurotoxicity of 2, 2', 4, 4'-tetrabromodiphenyl ether (PBDE-47) and the interaction of PBDE-47 with 2, 2', 4, 4', 5, 5'-hexachlorobipheny (PCB153) were investigated herein, as the dominant congener forms of PBDEs and PCBs, respectively. SD rats were exposed to a single oral dose of PBDE-47 (1, 5, and 10 μg/g) and/or PCB153 (5 μg/g) on post-natal day (PND) 10. Concentrations of PBDE-47, triiodothyronine (T(3)), thyroxine (T(4)), and thyroid-stimulating hormone (TSH) in serum; organ-to-body weight ratios; as well as long-term learning and memory were measured in 2-month-old rats. The present study found that some doses of PBDE-47 decreased the organ-to-body weight ratios of the thyroid and uterus, decreased the concentration of T(4) in serum, and increased the organ-to-body weight ratio of the ovaries (p < 0.05). PCB153 could increase the action of PBDE-47 during combined exposure, but this interaction was not found between PBDE-47 and PCB153. In a Morris water maze experiment, the latency periods were significantly prolonged and time ratios were obviously depressed in all PBDE-47-treated groups compared to the control (p < 0.05); furthermore, significant interactions between PBDE-47 and PCB153 were observed (p < 0.05). In conclusion, PBDE-47 may depress thyroid development as well as the long-term learning and memory capabilities in adult rats exposed to PBDE-47 on PND 10. PCB153 can interact with PBDE-47, resulting in an increase in developmental neurotoxicity.

• Authors: Ping He, Aiguo Wang, Qiang Niu, Lijuan Guo, Tao Xia, Xuemin Chen
• Journal: Toxicology and industrial health (Toxicol Ind Health) Vol. 27 Issue 3 Pg. 279-88 (Apr 2011) ISSN: 1477-0393 [Electronic] England
• PMID: 20947653 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Flame Retardants
• Halogenated Diphenyl Ethers
• Thyroid Hormones
• 2,2',4,4'-tetrabromodiphenyl ether
• Polychlorinated Biphenyls
• 2,4,5,2',4',5'-hexachlorobiphenyl

Topics

• Animals
• Animals, Suckling
• Drug Synergism
• Drug Therapy, Combination
• Female
• Flame Retardants (toxicity)
• Halogenated Diphenyl Ethers (toxicity)
• Male
• Maze Learning (drug effects, physiology)
• Memory (drug effects, physiology)
• Organ Size (drug effects)
• Ovary (drug effects, pathology)
• Polychlorinated Biphenyls (toxicity)
• Rats
• Rats, Sprague-Dawley
• Thyroid Gland (drug effects, growth & development, pathology)
• Thyroid Hormones (blood)
• Uterus (drug effects, pathology)