PUBLICATION

Toxicological Evaluation of SiO₂ Nanoparticles by Zebrafish Embryo Toxicity Test

Authors

Vranic, S., Shimada, Y., Ichihara, S., Kimata, M., Wu, W., Tanaka, T., Boland, S., Tran, L., Ichihara, G.

ID

ZDB-PUB-190220-8

Date

2019

Source

International Journal of Molecular Sciences 20(4): (Journal)

Registered Authors

Tanaka, Toshio

Keywords

bio-distribution, dechorionation, embryo acute toxicity test, silica nanoparticles, surface functionalization, vascularization, zebrafish

MeSH Terms

Toxicity Tests*
Chorion/metabolism
Animals
Suspensions
Nanoparticles/toxicity*
Gene Expression Regulation, Developmental/drug effects
Neovascularization, Physiologic/drug effects
Embryo, Nonmammalian/anatomy & histology
Embryo, Nonmammalian/blood supply
Embryo, Nonmammalian/drug effects*
Silicon Dioxide/toxicity*
Survival Analysis
Vascular Endothelial Growth Factor A/genetics
Vascular Endothelial Growth Factor A/metabolism
Zebrafish/embryology*
Receptors, Vascular Endothelial Growth Factor/genetics
Receptors, Vascular Endothelial Growth Factor/metabolism
Protective Agents/metabolism

PubMed

30781642 Full text @ Int. J. Mol. Sci.

Abstract

As the use of nanoparticles (NPs) is increasing, the potential toxicity and behavior of NPs in living systems need to be better understood. Our goal was to evaluate the developmental toxicity and bio-distribution of two different sizes of fluorescently-labeled SiO₂ NPs, 25 and 115 nm, with neutral surface charge or with different surface functionalization, rendering them positively or negatively charged, in order to predict the effect of NPs in humans. We performed a zebrafish embryo toxicity test (ZFET) by exposing the embryos to SiO₂ NPs starting from six hours post fertilization (hpf). Survival rate, hatching time, and gross morphological changes were assessed at 12, 24, 36, 48, 60, and 72 hpf. We evaluated the effect of NPs on angiogenesis by counting the number of sub-intestinal vessels between the second and seventh intersegmental vessels and gene expression analysis of vascular endothelial growth factor (VEGF) and VEGF receptors at 72 hpf. SiO₂ NPs did not show any adverse effects on survival rate, hatching time, gross morphology, or physiological angiogenesis. We found that SiO₂ NPs were trapped by the chorion up until to the hatching stage. After chemical removal of the chorion (dechorionation), positively surface-charged SiO₂ NPs (25 nm) significantly reduced the survival rate of the fish compared to the control group. These results indicate that zebrafish chorion acts as a physical barrier against SiO₂ NPs, and removing the chorions in ZFET might be necessary for evaluation of toxicity of NPs.

Genes / Markers

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