Toxicological Study Of Palladium On Embryonic Development Of Zebrafish

With the rapid development of science and technology, Palladium(Pd) have been playing an important role in modern life, Palladium is widely used in a variety of application such as aerospace industry, automotive manufacturing, catalytic jewelry manufacturing and others.Meanwhile Nano-Palladium serves as an emerging nanoparticles,which is widely used in modern industry and medical applications and so on. But with the increasing use of palladium, it is progressively accumulating in the environment, especially in aquatic ecosystem. In present people have little upstanding knowledge,about the toxicity of palladium, the potential toxicity of Pd has therefore caused extensive concern world widely. In the present study, we aimed to investigate the Pd-induced developmental toxicity and potential molecular mechanism by taking advantage of zebra fish model.The main results are as follows:(1) Sublethal effects of palladium ion and Nano-palladium on zebrafish embryos(2) Lethal effects of Nano-palladium on zebrafish embryos;(3) Explore the toxicological mechanisms of palladium (PdCl2) and different size nano-palladium on the zebra fish embryos.Our results indicated that when palladium (PdCl2) and nana-palladium suspending liquid high does exposition can suppress the zebrafish embryonic development, inhibit hatching rate, the exposed group juvenile fish body long reduces, the growth abnormal (such as cardiac malformation, yolk sac dropsy, pericardial edema, heart rate slow-down, the performance is a rear part/The dorsal chord is curving, aspect and so on melanin reduction), even lead to embryonic lethality. Moreover, we also found palladium (PdCl2) and nano-palladium was involved in regulation of gene expression through Real-time PCR. Similar to other metals, Pd exposure resulted in the elevated expression of general metal-inducible genes, down-regulated the expression of several antioxidant enzymes which reflects the increased production of reactive oxygen species. We also found mRNA expression levels of several cardiac-related genes were affected by PdCl2, suggesting a potential molecular mechanism of Pd-induced cardiac malformation of zebra fish embryos. On the other hand,80nm nano-palladium exposure resulted in up-regulated the expression of Box and Noxa of Bcl-2family, which suggest a potential molecular mechanism of nano-palladium-induced apoptosis of zebra fish embryo. Taken together, our study investigated the effects of Pd on zebra fish embryonic development and its potential molecular mechamsms, paving the way for the full understanding of Pd toxicity.