Silver nanocolloids disrupt medaka embryogenesis through vital gene expressions

TitleSilver nanocolloids disrupt medaka embryogenesis through vital gene expressions
Publication TypeJournal Article
Year of Publication2012
AuthorsKashiwada, S, Ariza, ME, Kawaguchi, T, Nakagame, Y, Jayasinghe, BS, Gärtner, K, Nakamura, H, Kagami, Y, Sabo-Attwood, T, Ferguson, PL, Chandler, GT
JournalEnvironmental Science & Technology
Volume46
Issue11
Start Page6278
Pagination6278 - 6287
Date Published01/2012
Abstract

Silver nanomaterials are the major components of healthcare products largely because of their antimicrobial effects. However, their unintended toxicity to biological organisms and its mechanism are not well understood. Using medaka fish embryo model, the toxic effects and corresponding mechanisms of silver nanocolloids (SNC, particle size 3.8 ± 1.0-diameter nm) were investigated. SNC caused morphological changes in embryos including cardiovascular malformations, ischemia, underdeveloped central nervous system and eyes, and kyphosis at exposures of 0.5 mg/L. Interestingly, SNC were observed inside the eggs at a level of 786.1 ± 32.5 pg/mg egg weight, and TEM analysis showed that SNC adhered to the surface and inside of the chorion. Meanwhile, medaka oligo DNA microarray and qRT-PCR were used for gene expression analysis in the embryos exposed to 0.05 mg/L SNC for 48 h. As a result, expressions of six of the oxidative stress-, embryogenesis- and morphogenesis-related genes, ctsL, tpm1, rbp, mt, atp2a1, and hox6b6, were affected by the SNC exposure, and these genes' involvement in those malformations was implied. Thus, SNC could potentially cause malformations in the cardiovascular and central nervous systems in developing medaka embryo through SNC-induced differential expression of the genes related to oxidative stress, embryonic cellular proliferation, and morphological development. © 2012 American Chemical Society.

DOI10.1021/es2045647
Short TitleEnvironmental Science & Technology