Comparative study on the neurotoxicity of five bisphenols using zebrafish embryos/larvae models

Area of Science:

• Environmental Toxicology
• Neuroscience
• Developmental Biology

Background:

• Bisphenols (BPs) are endocrine-disrupting chemicals with known neurotoxic potential.
• Comparative neurotoxicity studies using equivalent concentrations of various BPs are limited.
• Understanding differential BP neurotoxicity is crucial for environmental health risk assessment.

Purpose of the Study:

• To comparatively assess the neurotoxicity of five bisphenols (BPA, BPS, BPF, BHPF, BPAF) in zebrafish embryos/larvae.
• To investigate the molecular mechanisms underlying BP-induced neurobehavioral abnormalities.
• To validate the use of equivalent concentrations for toxicity assessment.

Main Methods:

• Zebrafish embryos/larvae were exposed to concentrations equivalent to 2% of each bisphenol's LC50.
• Neurobehavioral assessments included body length, mortality, hatching rate, heart rate, eye span, locomotor activity, and anxiety-like behaviors.
• Gene expression analysis targeted GABAergic, dopaminergic, cholinergic, neurodevelopmental, oxidative stress, and metabolic pathways.

Main Results:

• All five bisphenols significantly reduced body length and increased mortality.
• Bisphenols induced hyperactivity and anxiety-like behaviors, affecting locomotor ability.
• Molecular analysis revealed downregulation of neurotransmitter-related genes and neurodevelopmental genes, alongside upregulation of oxidative stress and metabolic genes.

Conclusions:

• Equivalent concentration comparison is a reliable method for assessing chemical toxicity.
• Bisphenols exhibit varying neurodevelopmental toxicity profiles, impacting neurotransmitter systems and inducing oxidative stress.
• Findings provide a basis for managing environmental chemical risks associated with bisphenol exposure.