title: Neonatal exposure to BDE 209 impaired learning and memory, decreased expression of hippocampal core SNAREs and synaptophysin in adult rats.
abstract: Polybrominated diphenyl ethers (PBDEs) are a class of flame retardants. While the mechanism remains unknown, the potential neurotoxic effects of PBDEs remain a relevant issue. In the present study, neonatal Sprague-Dawley rats of both sexes were administered BDE 209 (1, 10, or 20mg/kg body weight) or peanut oil once daily from postnatal day (PND) 5 to PND 10. We examined the spatial learning and memory by Morris water maze and the working and reference memory by eight-arm radial maze in the stage of adulthood. Compared with controls, significantly longer escape latencies and fewer platform-crossings in the Morris water maze were observed in rats exposed to 1, 10, and 20mg/kg BDE 209, and these effects were dose-dependent. Significantly higher working and reference memory error rates in the eight-arm radial maze were also observed in rats exposed to 10 and 20mg/kg BDE 209. Furthermore, we detected the mRNA and protein expressions of hippocampal synaptobrevin 2, syntaxin 1A, Synaptosome Associated Protein 25 (SNAP-25), and synaptophysin using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot methods. Compared with controls, the mRNA expressions of synaptobrevin 2, syntaxin 1A, SNAP-25, and synaptophysin were significantly decreased in the hippocampi of rats exposed to 1, 10, and 20 mg/kg BDE 209, and the protein expressions of synaptobrevin 2 and SNAP-25 were significantly decreased in the hippocampi of rats exposed to 10 and 20 mg/kg BDE 209, while syntaxin 1A and synaptophysin were significantly decreased in rats exposed to 1, 10, and 20 mg/kg BDE 209. Alterations that may be involved in the learning and memory deficits induced by BDE 209 reveal the possibility of synapse loss.
authors.affiliation: Department of Occupational Medicine, School of Public Health, Southwest Medical University, Luzhou City 646000, PR China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Li
authors.affiliation: Experimental Teaching Center, School of Public Health, Southwest Medical University, Luzhou City 646000, PR China.
authors.forename: Chunmei
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Public Health, School of Public Health, Southwest Medical University, Luzhou City 646000, PR China.
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Prevention Medicine, School of Public Health, Southwest Medical University, Luzhou City 646000, PR China.
authors.forename: Chengwei
authors.initials: C
authors.lastname: Yue
authors.affiliation: Experimental Teaching Center, School of Public Health, Southwest Medical University, Luzhou City 646000, PR China. Electronic address: tangyan200310@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Tang
mesh_terms: D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D004305:Dose-Response Relationship, Drug; D005260:Female; D005411:Flame Retardants / Q000633:toxicity*; D005786:Gene Expression Regulation / Q000187:drug effects; D055768:Halogenated Diphenyl Ethers / Q000633:toxicity*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007859:Learning Disabilities / Q000139:chemically induced*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced*; D012333:RNA, Messenger; D051381:Rats; D017207:Rats, Sprague-Dawley; D050600:SNARE Proteins / Q000235:genetics / Q000378:metabolism*; D016708:Synaptophysin / Q000235:genetics / Q000378:metabolism*
chemical_list: D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D012333:RNA, Messenger; D050600:SNARE Proteins; D016708:Synaptophysin; C010902:decabromobiphenyl ether
keywords: Decabromodiphenyl ether; Developmental neurotoxicity; Hippocampus; Learning and memory; SNAREs; Synaptophysin