Activation of the Aryl Hydrocarbon Receptor by Methyl Yellow and Related Congeners: Structure-Activity Relationships in Halogenated Derivatives.
作者:Taka-aki Kato、Tomonari Matsuda、Saburo Matsui、Takaharu Mizutani、Ken-ichi Saeki
DOI:10.1248/bpb.25.466
日期:——
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates the biological action of many environmental compounds. Methyl yellow (4-dimethylaminoazobenzene; MY) is a principal azo-dye, and structurally related compounds were subjected to analysis of structure–activity relationships as AhR ligands by using a yeast AhR signaling assay. The effects of halogen-substitution among 23 halogenated MYs on the AhR ligand activity can be summarized as follows: enhancement by halogen-substitution at the ortho-position (2′- and 6′-position), and reduction by substitution at the para-position (4′-position). The greatest enhancement of the ligand activity was observed in 2′,6′-dichlorinated MY (13.5-fold of MY), and its AhR ligand activity was very close to that of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the present assay system. In the study of compounds structurally related to MY, benzanilide (BA) showed almost the same AhR ligand activity as azobenzene and trans-stilbene. Furthermore, 4′-chlorobenzanilide, in which the length of the molecule is similar to that of MY, enhanced the AhR ligand activity by ortho(2′)-chlorine-substitution, and the AhR ligand activity of 2′,4′-dichlorobenzanilide was similar to that of 2′-chloro-MY. These results suggest that the amide bond is equivalent to the –N=N– or –CH=CH– double bond for recognition as the ligand by AhR in 1,2-diphenyl-1,2-ene derivatives.
芳香烃受体(AhR)是一种配体激活的转录因子,可介导多种环境化合物的生物作用。甲基黄(4-二甲氨基偶氮苯;MY)是一种主要的偶氮染料,通过使用酵母AhR信号检测方法,对结构相关化合物进行了结构-活性关系分析,以评估其作为AhR配体的特性。
对23种卤代甲基黄的AhR配体活性的卤素取代效应可总结如下:邻位(2'和6'位)的卤素取代增强活性,对位(4'位)取代则降低活性。2',6'-二氯代甲基黄表现出最强的配体活性增强效果(是MY的13.5倍),其AhR配体活性与2,3,7,8-四氯二苯并-p-二恶英(TCDD)在本检测系统中的活性非常接近。
在研究与MY结构相关的化合物时发现,苯甲酰苯胺(BA)显示出与偶氮苯和反式二苯乙烯几乎相同的AhR配体活性。此外,分子长度与MY相似的4'-氯代苯甲酰苯胺通过邻位(2')氯取代增强了AhR配体活性,2',4'-二氯代苯甲酰苯胺的AhR配体活性与2'-氯代-MY相似。
这些结果表明,在1,2-二苯基-1,2-烯衍生物中,酰胺键与-N=N-或-CH=CH-双键在被AhR识别为配体时具有等效作用。