BDE-47和BDE-209对乙酰胆碱酯酶(AChE)活性的抑制特性及分子作用力研究  

Inhibitory Characteristics and Molecular Forces of BDE-47 and BDE-209 on Acetylcholinesterase(AChE)

作　　者：巫川 王树涛[1] 朱婧 尤宏[1] 

机构地区：[1]哈尔滨工业大学城市水资源与水环境国家重点实验室,哈尔滨150090

出　　处：《生态毒理学报》2017年第6期99-106,共8页Asian Journal of Ecotoxicology

基　　金：哈尔滨工业大学城市水资源与水环境国家重点实验室开放基金项目

摘　　要：多溴联苯醚(PBDEs)是应用广泛的溴代阻燃剂,其中2,2',4,4'-四溴联苯醚(BDE-47)和2,2',3,3',4,4',5,5',6,6'-十溴联苯醚(BDE-209)广泛存在于环境中。PBDEs具有神经毒性,但其致毒机制尚不明确。本文通过研究BDE-47与BDE-209对乙酰胆碱酯酶(AChE)活性的影响及二者与AChE相互作用的光谱分析,揭示BDE-47与BDE-209导致神经毒性的致毒机制。BDE-47和BDE-209在一定浓度范围内均能够抑制AChE分解乙酰胆碱;随着浓度的增加,两者的抑制率均呈现出先增加后降低的规律。BDE-47浓度为400μmol·L-1时抑制率达到最大,为22.3%;BDE-209浓度为200μmol·L-1时抑制率达到最大,为11.2%。相同浓度下,BDE-47对AChE的抑制率始终大于BDE-209,表明AChE对BDE-47更加敏感。荧光光谱分析结果表明BDE-47和BDE-209与AChE之间的相互作用均主要为疏水作用,同时不存在范德华引力作用;BDE-47与AChE的结合常数大于BDE-209与AChE的结合常数,表明BDE-47更易与AChE相互作用。此外,温度的升高不利于BDE-47和BDE-209与AChE之间相互作用。BDE-47和BDE-209抑制AChE活性很可能是导致神经毒性通路之一。Polybrominated diphenyl ethers （PBDEs） are widely used as brominated flame retardants, among which both 2,2＇ ,4,4＇ -tetrabromodiphenylether （BDE-47） and 2,2＇ ,3,3＇ ,4,4＇ ,5,5＇ ,6,6＇ -decabromodiphenyl ether （BDE-209） are often detected in the environment. As known, PBDEs is of concern for the neurotoxicity. However, the neuro- toxicological mechanism is not clear yet. The effects of BDE-47 and BDE-209 on the activity of acetylcholinester- ase （ACHE） and the interaction between BDE-47, BDE-209 and AChE were investigated. The potential neuro-toxi- cological mechanism of BDE-47 and BDE-209 was also revealed. The results showed that BDE-47 and BDE-209 could inhibit AChE decomposition of acetylcholine in a certain concentrations range. With the increase of concentrations, the inhibition rates of BDE-47 and BDE-209 increased at first and decreased subsequently, and the maxi- mum inhibition rate were 22.3% and 11.2%, respectively, at the concentration of BDE-47 of 400 p^mol-L1 and of BDE-209 of 200 p^mol. L1. At the same concentration, the inhibition of BDE-47 to AChE was always stronger than that of BDE-209, indicating that AChE was more sensitive to BDE-47. The results of fluorescence spectrosco- py showed that the interaction between BDE-47 and BDE-209 and AChE was dominated by hydrophobic force. The binding constant of BDE-47 with AChE was greater than that of BDE-209 with ACHE, suggesting that BDE- 47 is more likely to interact with ACHE. In addition, the increase of temperature restrains the interaction of BDE-47 and BDE-209 with ACHE. The inhibition of BDE-47 and BDE-209 to AChE activity is likely to be one of the neu- rotoxic pathways.

关 键 词：BDE-47 BDE-209 乙酰胆碱酯酶(AChE) 分子作用力 荧光光谱 

分 类 号：X171.5[环境科学与工程—环境科学]