Estrogenic activity of by-products produced by the reaction of estrogens with hypochlorous acid.

源于人类和动物的雌激素被认为是环境中内分泌干扰物的一个因素。我们研究了它们的卤代衍生物，这些衍生物可以通过污水处理厂的氯处理而产生。在有机溶剂中与次氯酸反应生成雌酮(EL)、17β-雌二醇(E_2)、雌三醇(E_3)和17 a-乙炔基雌二醇(E_2)的氯代衍生物，并在有溴离子存在的情况下生成溴代衍生物。用酵母双杂交方法检测了卤代衍生物的雌激素活性，分别与人雌激素受体a(HERα)或青鱼(Oryzias Latipe)雌激素受体a(Mederα)结合。虽然4-CIE1和10-氯-L，4-雌二烯-3，17-二酮的活性与EL相似，但2-C1E_1和2，4-diCIE1的活性分别约为EL的4/5和1/50，对她的α的激动剂。在2，4，16，16-四氯乙烷中未检测到活性。E_2、E_3和E_2的氯化衍生物的雌激素活性与E_1相似。溴化衍生物的活性略弱于相应的氯化衍生物。在人乳腺癌MCF7细胞中设计的GFP表达系统和细胞增殖实验中也得到了类似的结果。事实上，在日本静冈县一座市政污水处理厂的出水中检测到了EL、2-ClE1、4-C1E1和2，4-diClE1的氯化衍生物。用实时荧光定量聚合酶链式反应分析氯化衍生物EL和E2对MCF7细胞基因表达水平的影响。两个被充分研究的雌激素反应基因PS2和PGR的水平随着氯化衍生物的雌激素活性的增加而增加。另一方面，AhR taeget基因、Cyplal水平降低。

Estrogens that originate from humans and animals are thought of as a factor of endocrine disruptors in the environment. We investigated their halogenated derivatives, which could be produced by chlorine treatment at a sewage treatment plant. The chlorinated derivatives of estrone (El), 17p-estradiol (E2), estriol (E3), and 17a-ethynylestradiol (EE2) were produced by the reaction with hypochlorous acid in organic solvents and also brominated derivatives when bromide ions were present. The estrogenic activities of the halogenated derivatives were measured by yeast two-hybrid assays incorporating the human estrogen receptor a (hERα) or medaka fish (Oryzias latipes) estrogen receptor a (medERα). Although the activities of 4-CIE1 and 10-chloro-l,4-estradiene-3,17-dione were similar to those of El, the activities of 2-C1E1 and 2,4-diCIE1 were approximately 4/5 and 1/50 that of El, respectively, in an agonist assay for hERα. No activity was detected in 2,4,16,16-tetraClE1. The estrogenicities of chlorinated derivatives of E2, E3, and EE2 showed a similar tendency to that of El. The brominated derivatives showed slightly weaker activity than the corresponding chlorinated derivatives. Similar results were obtained in a devised GFP expression system in human breast carcinoma MCF7 cells and in their cell proliferation assay. In fact, chlorinated derivatives of El, 2-ClE1, 4-C1E1 and 2,4-diClE1 in the effluent of a municipal sewage treatment plant located in Shizuoka prefecture, Japan were detected. The effects of chlorinated derivatives of El and E2 on the gene expression levels in MCF7 cells were analyzed by real-time quantitative PCR. The levels of two well-studied estrogen-responsive genes, pS2 and PgR, increased corresponding to the estrogenicity of chlorinated derivatives. On the other hand, AhR taeget gene, Cyplal levels were decreased.