Zebrafish Vascular Toxicity

There is growing concern and evidence for adverse human health effects due to elevated exposure to environmental pollutants, including pesticides and industrial chemicals. One of the toxicity endpoints relevant to human health is the disruption of vascular development. The vascular network is the first fully functional tissue system to be formed during embryonic development. It is sensitive to chemical perturbation and vascular toxicity is associated with adverse developmental outcomes including embryo resorption, skeletal defects, and fetal weight reduction. Thus, screening for vascular toxicity provides information relevant to the developmental toxicity profile of environmental chemicals.

Zebrafish (Danio rerio) is a popular model for investigating vascular toxicity, as its gene pattern of vasculogenesis and angiogenesis is similar to humans. Vascular development was divided into two stages: vasculogenesis, de novo formation of vessels, and angiogenesis, which involves the sprouting of new vessels from preexisting ones. The vascular endothelial growth factor (VEGF) signaling pathway regulates vasculogenesis and angiogenesis through endothelial cell proliferation, promoting cell migration and inhibition of apoptosis. In zebrafish, VEGFa is the key driver of vascular development. VEGFa is transferred maternally and expressed at a very early stage, declining to very low levels at 8.5 h post-fertilization (hpf) or 80% epiboly. Embryonic zebrafish develop ex utero and are also transparent, allowing for the visualization of vascular morphological changes in real-time. For example, vascular development in zebrafish larvae can be tracked in real-time through visualizing the whole circulatory system by using transgenic lines with fluorescent markers.

Figure 1. Developmental angiogenesis toxicity assay. (Tal T, et al., 2017)

Our Vascular Toxicity Evaluation in Zebrafish

To identify vascular disruptor compounds (VDCs), Creative Biogene deployed multiple angiogenesis assays in transgenic zebrafish embryos. Our transgenic Tg(kdrl:EGFP) and Tg(fli1:EGFP) zebrafish embryos are available to identify chemicals that impair developmental angiogenesis.

Workflow

• Zebrafish chemical treatments
• Quantification of dorsal longitudinal anatomotic vessels (DLAVs) growth
• Angiogenesis toxicity screen: Caudal vein (CV), intersegmental vessel (ISV), sub-intestinal vessel (SIV), yolk vessel, and eye (E) vessel structures were assessed.
• Zebrafish ISV and caudal vein plexus (CVP) image analysis: Segmentation and feature extraction algorithms were developed to analyze images of exposed zebrafish embryos for the two most common malformations, ISV morphology (ISV count; the total area of ISV; average distance between ISV; and average ISV length) and condensation of CVP (shape quantification of CVP and fenestrations).
• Quantitative reverse-transcription polymerase chain reaction (qRT-PCR)

Our Advantages

• Wide ranges of detection technologies
• Easy and flexible workflow
• Advanced high-content screening equipment
• Excellent predictability

Contact us to learn more about our zebrafish vascular toxicity assay services.

References

1. Tal T, et al. Screening for angiogenic inhibitors in zebrafish to evaluate a predictive model for developmental vascular toxicity. Reproductive Toxicology, 2017, 70: 70-81.
2. McCollum C W, et al. Identification of vascular disruptor compounds by analysis in zebrafish embryos and mouse embryonic endothelial cells. Reproductive Toxicology, 2017, 70: 60-69.
3. Yeh C H, et al. Caffeine treatment disturbs the angiogenesis of zebrafish embryos. Drug and chemical toxicology, 2012, 35(4): 361-365.
4. Gao J, et al. Vascular toxicity of silver nanoparticles to developing zebrafish (Danio rerio). Nanotoxicology, 2016, 10(9): 1363-1372.

For research use only. Not intended for any clinical use.