Development of multi-generation assay for endocrine disrupting chemicals

本研究旨在建立一种多代毒性测定方法，用于化学品的生物学评价。线虫秀丽隐杆线虫被采用为模式生物。在此基础上，我们进行了五代以上的亚致死毒性、繁殖力和生殖力的测定。结果表明，C.线虫对脊椎动物类固醇激素有反应特别是雌二醇具有胆固醇样的效力，支持C。优雅而睾酮和己烯雌酚则抑制C.优雅用同样的方法对一些化学品进行了评价。特别是双酚A降低了C.甚至在1 nM时也显著地增加。用磷酸化氨基酸的特异性抗体进行蛋白质印迹分析，发现雌二醇暴露后，雌虫体内某些蛋白质的磷酸化水平发生了变化。这些结果表明，该毒性测定的灵敏度比LC_（50）和自由活线虫C.线虫正成为测试包括生殖中断在内的化学毒性的有效模式生物。

In this study, we investigated to develop a multiple-generation toxicity assay for biological evaluation of chemicals. The nematode Caenorhabditis elegans was adopted for a model organism. Then we examined the sublethal toxicity, fecundity and reproduction for over five generations. As the results, C. elegans responds to vertebrate steroid hormones. Especially estradiol has a cholesterol-like potency in supporting the reproduction of C. elegans. In contrast testosterone and diethylstibestrol suppressed the fecundity rate of C. elegans. Some chemicals were evaluated by same method. In particular, bisphenol A was decreased the number of C. elegans significantly even at 1 nM. A comparison of the number of viable worms and eggs suggested that the phenols exert hatching toxicity.When we performed western-blotting analyses using specific antibodies for phosphorylated amino acids, we could detect some proteins which phosphorylation levels were changed in estradiol exposed C. elegans extracts.These results indicated that this toxicity assay had 100-1000-fold higher sensitivity than the LC50s and free living nematode C. elegans is becoming an effective model organism for testing chemical toxicity including reproductive disruption.