持久性有机污染物六溴环十二烷(HBCD)是一种高含溴量阻燃剂，广泛应用在与人们日常生活密切相关的涤纶织物、塑料、纤维和建筑物保温材料中，HBCD进入机体主要富集在脂肪组织。尽管目前针对HBCD的毒性已开展了大量研究，但有关HBCD对脂肪组织的毒性却很少关注，HBCD对肥胖发生和脂肪细胞的影响仍不清楚。申请人前期的研究结果表明， HBCD暴露具有诱发腹内脂肪增加和干扰脂肪细胞分化的效应，此外，有文献报道HBCD具有加剧已有肥胖的效应。在此基础上，本项目将深入探讨：1）低剂量HBCD长期暴露诱发肥胖发生的毒性效应特征；2）HBCD暴露对白色脂肪细胞分化成熟、米色脂肪细胞与白色脂肪细胞转化的影响及相关转录因子、重要信号通路所介导的诱发肥胖的毒性机制研究；3）阐明α-HBCD，β-HBCD，γ-HBCD在促肥胖效应中的毒性效应差异。本项目的开展将为全面深刻评价HBCD的环境健康风险提供科学依据

Hexabromocyclododecane (HBCD) is a high bromine content fire retardant, which belongs to the Persistent Organic Pollutants(POPs). HBCD is widely used in exterior building insulation materials, such as expanded polystyrene (EPS) and extruded polystyrene (XPS), and is also added into electrical equipment, high impact polystyrene (HIPS), and textile coatings. HBCD is prone to accumulate in the organism and adipose tissue is one of main organs which accumulated. Although there has been a number of studies focused on the toxicity of HBCD, the toxicity of HBCD on adipose is little mentioned and the influence of HBCD on obesity development and adipocytes is still to be unclear. Our group observed that HBCD exposure lead to preadipocyte differentiation and adipose accumulation in vivo in the previous study, in addition, others reported that HBCD exposure aggravated HFD induced obisity. Based on these realization, we will carry out following work in this project: 1) To reveal the effects of low dose HBCD exposure on obesity development in vivo; 2)To examine the effects of HBCD exposure on white preadipocyte differentiation, transdifferentiation between mature white adipocyte and beige adipocyte and elucidate the molecular mechanisms underlying HBCD exposure mediated obesity development by analyzing transcription factors, key signal transduction pathways correlated to white preadipocyte differentiation and transdifferentiation between mature white adipocyte and beige adipocyte . 3) To elucidate different effects of α-HBCD，β-HBCD，γ-HBCD on HBCD induced obesity. Thus, this project will provide theoretical basis and scientific guidance for the environmental health risky of HBCD.