The copper ion (Cu²⁺) has been reported to suppress the hatching of fish. However, little is known about the underlying mechanism. In this study, copper nanoparticles (CuNPs) and Cu²⁺ were shown to significantly suppress hatching of zebrafish in a dosage-dependent manner, and reactive oxygen species (ROS) scavengers NAC (N­acetylcysteine) & GSH (reduced glutathione) and Wnt signaling agonist BIO (6­bromoindirubin­3′­oxime) significantly alleviated the suppressing effects of Cu²⁺ and CuNPs on egg hatching. Mechanistically, NAC, GSH, and BIO recovered the egg hatching in copper-treated group via increasing the embryonic motility rather than stimulating the expression and secretion of hatching enzymes before hatching. Additionally, no significant difference in egg hatching was observed between the control and Cu²⁺-treated group at 72 hpf (hours post fertilization) in cox17 mutant embryos, in which little ROS was producd after copper stimulation. This may be the first report that Cu²⁺ and CuNPs suppress embryonic motility and the subsequent hatching via inducing ROS and at the same time down-regulating Wnt signaling in fish embryos.

据报道，铜离子（Cu ²⁺）可以抑制鱼类的孵化。但是，对于底层机制知之甚少。在这项研究中，铜纳米颗粒（CuNPs）和Cu ²⁺被证明以剂量依赖性方式显着抑制斑马鱼的孵化，并且活性氧（ROS）清除剂NAC（N乙酰半胱氨酸）和GSH（还原型谷胱甘肽）和Wnt信号传导激动剂BIO（6bromoindirubin3'oxime）明显减轻了Cu ²⁺和CuNPs对卵孵化的抑制作用。机械地，NAC，GSH和BIO回收的蛋在铜处理组孵化经由提高孵化率，而不是在孵化前刺激孵化酶的表达和分泌。另外，在cox17突变体胚胎中，在受精后72 hpf（受精后数小时），对照组和Cu ²⁺处理组之间在卵孵化方面没有观察到显着差异，其中铜刺激后几乎没有产生ROS。这可能是第一个关于Cu ²⁺和CuNPs通过诱导ROS抑制胚胎运动和随后孵化的报告，同时下调了鱼胚中的Wnt信号传导。