Increased Cellular Distribution of Vimentin and Ret in the Cingulum of Rat Offspring After Developmental Exposure to Decabromodiphenyl Ether or 1,2,5,6,9,10-Hexabromocyclododecane

Abstract: To determine effects of developmental exposure to brominated flame retardants (BFRs), weak thyroid hormone disruptors, on white matter development, white matter-specific global gene expression analysis was performed using microdissection techniques and microarrays in male rats exposed maternally to decabromodiphenyl ether (DBDE), one of the representative BFRs, at 10, 100 or 1000 ppm. Based on previous gene expression profiles of developmental hypothyroidism and DBDE-exposed cases, vimentin⁺ immature astrocytes and ret proto-oncogene (Ret)⁺ oligodendrocytes were immunohistochemically examined after developmental exposure to representative BFRs, i.e., DBDE, 1,2,5,6,9,10-hexabromocyclododecane (HBCD; 100, 1000 or 10,000 ppm) and tetrabromobisphenol A (TBBPA; 100, 1000 or 10,000 ppm). Vimentin⁺ and Ret⁺ cell populations increased at ≥ 100 ppm and ≥ 10 ppm DBDE, respectively. Vimentin⁺ and Ret⁺ cells increased at ≥ 1000 ppm HBCD, with no effect of TBBPA. The highest dose of DBDE and HBCD revealed subtle fluctuations in serum thyroid-related hormone concentrations. Thus, DBDE and HBCD may exert direct effects on glial cell development at ≥ middle doses. At high doses, hypothyroidism may additionally be an inducing mechanism, although its contribution is rather minor.     

溴系阻燃剂(BFRs)的动物内分泌干扰(ED)研究

近年来,防火溴系阻燃剂(Brominated flame retardants,BFRs)是在聚合物和织物中应用最为广泛的阻燃剂之一,广泛应用于各种家用和工业产品。BFRs属持久性有机污染物,目前在环境中已普遍存在,已在国际上引起了广泛的关注。由于BFRs的使用量在逐年增大,在土壤、沉积物、大气和生物体中普遍检测出BFRs。BFRs对水生动物、鸟类、哺乳动物都存在不同程度的毒害作用,其分布的广泛性、难降解性和对人体健康的不确定性已引起人们的普遍关注。基于国外动物毒理学研究成果,文章综合论述了BFRs及其代谢化合物对不同动物的内分泌干扰活性,主要介绍了对甲状腺激素水平、雌激素水平、雄激素水平及对动物神经系统发育的影响,为评价BFRs对动物和人类的健康影响提供理论基础。