The thyroid hormone system disrupting potential of resorcinol in fish.

Environmental pollutants capable of interfering with the thyroid hormone (TH) system increasingly raise concern for both human and environmental health. Recently, resorcinol has received attention as a compound of concern due to its endocrine disrupting properties. It is a known inhibitor of thyroperoxidase (TPO), an enzyme required in TH synthesis, and therapeutic use of resorcinol exposure has led to hypothyroidism in humans.

Deiodinase inhibition impairs the formation of the three posterior swim bladder tissue layers during early embryonic development in zebrafish.

Thyroid hormone system disruption (THSD) negatively affects multiple developmental processes and organs. In fish, inhibition of deiodinases, which are enzymes crucial for (in)activating thyroid hormones (THs), leads to impaired swim bladder inflation. Until now, the underlying mechanism has remained largely unknown.

Cross-species applicability of an adverse outcome pathway network for thyroid hormone system disruption.

Thyroid hormone system disrupting compounds are considered potential threats for human and environmental health. Multiple adverse outcome pathways (AOPs) for thyroid hormone system disruption (THSD) are being developed in different taxa. Combining these AOPs results in a cross-species AOP network for THSD which may provide an evidence-based foundation for extrapolating THSD data across vertebrate species and bridging the gap between human and environmental health.

New approach methods to improve human health risk assessment of thyroid hormone system disruption-a PARC project.

Current test strategies to identify thyroid hormone (TH) system disruptors are inadequate for conducting robust chemical risk assessment required for regulation. The tests rely heavily on histopathological changes in rodent thyroid glands or measuring changes in systemic TH levels, but they lack specific new approach methodologies (NAMs) that can adequately detect TH-mediated effects. Such alternative test methods are needed to infer a causal relationship between molecular initiating events and adverse outcomes such as perturbed brain development.

Getting more out of the zebrafish light dark transition test.

In (eco-)toxicological studies the light/dark transition (LDT) test is one of the most frequently used behaviour assays with zebrafish eleutheroembryos. However, study results vary regarding data presentation and analysis and mostly focus on a limited amount of the recorded data. In this study, we investigated whether monitoring two behavioural outcomes (time and distance moved) together with analysing multiple parameters can improve test sensitivity and data interpretation.

Clozapine modulation of zebrafish swimming behavior and gene expression as a case study to investigate effects of atypical drugs on aquatic organisms.

Mental illnesses affect more than 150 million people in Europe and lead to an increasing consumption of neuroactive drugs during the last twenty years. The antipsychotic compound, clozapine, is one of the most used psychotropic drugs worldwide, with potentially negative consequences for the aquatic environment. Hence, the objectives of the study presented here were the quantification of clozapine induced changes in swimming behavior of exposed Danio rerio embryos and the elucidation of the molecular effects on the serotonergic and dopaminergic systems.

Effects of 25 thyroid hormone disruptors on zebrafish embryos: A literature review of potential biomarkers.

It is estimated that many organic compounds found in our environment can interfere with the thyroid system and act as thyroid hormone (TH) disruptor. Despite that, there is a clear lack of assays to identify TH disruptors. Recently zebrafish embryos were suggested as screening tool to identify compounds which impact thyroid synthesis.

Nanosized titanium dioxide influences copper-induced toxicity during aging as a function of environmental conditions.

Titanium dioxide nanoparticles (TiO2 -NPs) adsorb co-occurring heavy metals in surface waters, modulating their toxicity for freshwater invertebrates. The processes triggering this interaction may be influenced by several environmental parameters; however, their relative importance remains unclear. The present study assessed the implications of aging on the joint acute toxicity of copper (Cu) and TiO2 -NPs for Daphnia magna over a duration of up to 72 h.