Dataset Information

Detection and Prioritization of Developmentally Neurotoxic and/or Neurotoxic Compounds Using Zebrafish.

ABSTRACT: The standard methods for toxicity testing using rodent models cannot keep pace with the increasing number of chemicals in our environment due to time and resource limitations. Hence, there is an unmet need for fast, sensitive, and cost-effective alternate models to reliably predict toxicity. As part of Tox21 Phase III's effort, a 90-compound library was created and made available to researchers to screen for neurotoxicants using novel technology and models. The chemical library was evaluated in zebrafish in a dose-range finding test for embryo-toxicity (ie, mortality or morphological alterations induced by each chemical). In addition, embryos exposed to the lowest effect level and nonobservable effect level were used to measure the internal concentration of the chemicals within the embryos by bioanalysis. Finally, considering the lowest effect level as the highest testing concentration, a functional assay was performed based on locomotor activity alteration in response to light-dark changes. The quality control chemicals included in the library, ie, negative controls and replicated chemicals, indicate that the assays performed were reliable. The use of analytical chemistry pointed out the importance of measuring chemical concentration inside embryos, and in particular, in the case of negative chemicals to avoid false negative classification. Overall, the proposed approach presented a good sensitivity and supports the inclusion of zebrafish assays as a reliable, relevant, and efficient screening tool to identify, prioritize, and evaluate chemical toxicity.

SUBMITTER: Quevedo C

PROVIDER: S-EPMC6390653 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Detection and Prioritization of Developmentally Neurotoxic and/or Neurotoxic Compounds Using Zebrafish.

Quevedo Celia C Behl Mamta M Ryan Kristen K Paules Richard S RS Alday Aintzane A Muriana Arantza A Alzualde Ainhoa A

Toxicological sciences : an official journal of the Society of Toxicology 20190301 1

The standard methods for toxicity testing using rodent models cannot keep pace with the increasing number of chemicals in our environment due to time and resource limitations. Hence, there is an unmet need for fast, sensitive, and cost-effective alternate models to reliably predict toxicity. As part of Tox21 Phase III's effort, a 90-compound library was created and made available to researchers to screen for neurotoxicants using novel technology and models. The chemical library was evaluated in ...[more]

PMID: 30521027

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Dataset Information

Detection and Prioritization of Developmentally Neurotoxic and/or Neurotoxic Compounds Using Zebrafish.

Publications

Detection and Prioritization of Developmentally Neurotoxic and/or Neurotoxic Compounds Using Zebrafish.

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