PUBLICATION
Time-course of coiling activity in zebrafish (Danio rerio) embryos exposed to ethanol as an endpoint for developmental neurotoxicity (DNT) - Hidden potential and underestimated challenges
- Authors
- Zindler, F., Beedgen, F., Braunbeck, T.
- ID
- ZDB-PUB-190701-22
- Date
- 2019
- Source
- Chemosphere 235: 12-20 (Journal)
- Registered Authors
- Braunbeck, Thomas
- Keywords
- Developmental delay, Ethanol, Locomotor activity, Tail movements, Visual motor response, Zebrafish embryos
- MeSH Terms
-
- Animals
- Embryo, Nonmammalian/drug effects*
- Ethanol/pharmacology
- Ethanol/toxicity*
- Neurotoxicity Syndromes/embryology
- Neurotoxicity Syndromes/etiology*
- Psychomotor Performance/drug effects
- Tail/physiopathology
- Zebrafish/embryology
- Zebrafish/growth & development
- PubMed
- 31254777 Full text @ Chemosphere
Citation
Zindler, F., Beedgen, F., Braunbeck, T. (2019) Time-course of coiling activity in zebrafish (Danio rerio) embryos exposed to ethanol as an endpoint for developmental neurotoxicity (DNT) - Hidden potential and underestimated challenges. Chemosphere. 235:12-20.
Abstract
Detection of developmental neurotoxicity (DNT) has been recognized as a major challenge by regulatory bodies and science. In search of sensitive and specific test methods, spontaneous tail coiling of embryonic zebrafish has been recommended as a promising tool for identification of DNT-inducing chemicals. The present study was designed to develop a protocol for a prolonged test to study neurotoxicity during the entire development of coiling movement in zebrafish embryos. Ambient illumination was found to modulate coiling activity from the very onset of tail movements representing the earliest behavioral response to light possible in zebrafish. In the dark, embryos displayed increased coiling activity in a way known from photokinesis, a stereotypical element of the visual motor response. Elevated coiling activity during dark phases allows for the development of test strategies that integrate later coiling movements under the control of a further developed nervous system. Furthermore, zebrafish embryos were exposed to ethanol, and coiling activity was analyzed according to the new test protocol. Exposure of embryos to non-teratogenic concentrations of ethanol (0.4-1%) resulted in a delay of the onset of coiling activity and heartbeat. Moreover, ethanol produced a dose-dependent increase in coiling frequency at 26 h post-fertilization, indicating the involvement of neurotoxic mechanisms. Analysis of coiling activity during prolonged exposure allowed for (1) attributing effects on coiling activity to different mechanisms and (2) preventing false interpretation of results. Further research is needed to verify the potential of this test protocol to distinguish between different mechanisms of neurotoxicity.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping