2,2',4,4'-四溴联苯醚通过核受体介导神经毒性作用机制的初步研究

目的：探讨2，2'，4，4'-四溴联苯醚（BDE-47）对人神经母细胞瘤SK-N-SH细胞增殖及对RXRα、TRs、PPARs核受体表达水平的影响，为阐明多溴联苯醚化合物神经毒性作用提供科学依据。方法：采用CCK-8法检测不同浓度BDE-47处理不同时间后的SK-N-SH细胞增殖情况；再以5、10和20 μmol/L BDE-47染毒细胞24 h后，分别采用DCFH-DA荧光法、WST-1法、比色法、qPCR法测定胞内ROS水平、SOD活力、GSH-Px活力及hOGG1 mRNA表达量；采用qPCR及Western blot检测BDE-47对RXRa、TRs、PPARs受体mRNA及蛋白表达水平的影响。结果：BDE-47抑制SK-N-SH细胞增殖，其抑制作用呈明显的时间和剂量效应关系（P < 0.05），24 h半数抑制浓度（IC₅₀）为75.94 μmol/L；与溶剂对照组相比，10和20 μmol/L BDE-47导致细胞内ROS水平上升、SOD活力下降、GSH-Px活力下降、hOGG1 mRNA水平上升，并可致SK-N-SH细胞氧化损伤（P < 0.05或P < 0.01）；BDE-47可诱导RXRα、TRs及PPARs受体各亚型mRNA及蛋白表达显著上升（P < 0.05或P < 0.01），并且对各亚型的诱导程度不一。结论：BDE-47抑制人神经母细胞瘤SK-N-SH细胞的增殖，导致氧化损伤，上调RXRα、TRs、PPARs核受体的表达从而介导神经毒性作用。

Preliminary study on mechanisms of neurotoxicity by 2, 2', 4, 4'- tetrabromodiphenyl ether via nuclear receptors

OBJECTIVE: To investigate the effects of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on cell proliferation and expression of the main nuclear receptors of RXRα,TRs and PPARs in human neuroblastoma SK-N-SH cells. METHODS:SK-N-SH cells were treated with different concentrations of BDE-47 and their proliferation was measured by the Cell Counting Kit-8 (CCK-8) assay. In addition,ROS level,SOD vitality,GSH-Px vitality and hOGG1 mRNA expression were analyzed by using the DCFH-DA,WST-1,colorimetric and qPCR assays,respectively. Involvement of the main nuclear receptors on expression of mRNA and protein were determined by qPCR and Western blot,respectively. RESULTS:BDE-47 inhibited cell proliferation and induced significant cytotoxicity in SK-N-SH cells. Dose- and time-dependent responses of the inhibitory effect were concentration-dependent,and the IC for 24-50 hours was 75.94 μmol/L. The expression levels in mRNA and protein of RXRα,TRs and PPARs in the treated cells were significantly increased compared with that in the control group,while induction of the isoforms was not consistent. CONCLUSION:BDE-47 inhibited proliferation of SK-N-SH cells via the induction of oxidative damage and neurotoxicity through up-regulating the expression of nuclear receptors:RXRα,TRs,and PPARs.