Zebrafish have gained popularity as a model organism due to their rapid, external, and transparent development, high fecundity, and gene homology with higher vertebrate models and humans. Specifically, drug discovery has had high success in the implementation of zebrafish in studies for target discovery, efficacy, and toxicity. However, a major limitation of the zebrafish model is a dependence on waterborne exposure in order to maintain high throughput capabilities. Dose delivery can be impeded by a matrix of N-linked glycoproteins and other polypeptides called the chorion. This acelluar barrier is protective of the developing embryo, and thus new approaches for assessment have involved their removal. In these studies, we explored the chorionic interference of a well-characterized alkylating chemotherapeutic, cisplatin, known to accumulate in the chorion of zebrafish and cause delayed hatching. Our results indicated that increased exposure of cisplatin due to dechorionation did not alter morphological endpoints, although retained confinement reduced total body length and yolk utilization. Additionally, inhibition of osteogenesis visualized with Alizarian Red staining, was observable in dechorionated and non-dechorionated treatment groups. The chorions of cisplatin-treated embryos showed resistance to degradation unless treated with a pronase solution. This may be may be due to cisplatin covalently crosslinking which reinforces the structure. As such, the chorion may play an advantageous role in studies to determine alkylating activity of novel compounds. Furthermore, the expression of zebrafish hatching enzyme was not affected by cisplatin exposure. These studies demonstrate that not only was recapitulation of mechanistic activity supported in zebrafish, but highly relevant off-target toxicities observed in higher vertebrates were identified in zebrafish, regardless of chorionation. Experimental design in drug discovery should consider preliminary studies without dechorionation in order to determine dose impediment or off-target adducting.

斑马鱼因其快速、外部、透明的发育、高繁殖力以及与高等脊椎动物模型和人类的基因同源性而作为模式生物而受到欢迎。具体而言，药物发现在斑马鱼的靶标发现、功效和毒性研究中取得了巨大成功。然而，斑马鱼模型的一个主要限制是依赖于水性暴露以保持高通量能力。 N-连接糖蛋白和其他称为绒毛膜的多肽基质可能会阻碍剂量递送。这种无细胞屏障可以保护发育中的胚胎，因此新的评估方法涉及去除它们。在这些研究中，我们探索了一种众所周知的烷基化化疗药物顺铂的绒毛膜干扰，已知顺铂会在斑马鱼的绒毛膜中积聚并导致孵化延迟。我们的结果表明，由于去绒毛膜去除而增加的顺铂暴露并没有改变形态学终点，尽管保留限制减少了总体长度和卵黄利用率。此外，在去绒毛膜和非去绒毛膜处理组中可以观察到通过茜红染色观察到的成骨抑制。顺铂处理的胚胎的绒毛膜表现出抗降解性，除非用链霉蛋白酶溶液处理。这可能是由于顺铂共价交联增强了结构。因此，绒毛膜可能在确定新型化合物的烷基化活性的研究中发挥有利的作用。此外，斑马鱼孵化酶的表达不受顺铂暴露的影响。 这些研究表明，不仅在斑马鱼中支持了机械活动的重现，而且在斑马鱼中也发现了在高等脊椎动物中观察到的高度相关的脱靶毒性，而与绒毛膜形成无关。药物发现中的实验设计应考虑不进行去绒毛膜化的初步研究，以确定剂量障碍或脱靶加合。