Neurotoxic Effects of Acute Tributyltin Exposure in Adult Zebrafish: Behavioral Impairments and Mechanistic Insights

TL;DR

This study explores how the chemical tributyltin harms the brains of adult zebrafish, causing behavioral issues and disrupting brain metabolism and signaling.

Contribution

The study provides a mechanistic framework linking TBT exposure to synaptic dysfunction and metabolic disruption in zebrafish.

Findings

TBT exposure caused significant brain tissue damage and disrupted energy metabolism in zebrafish.

TBT exposure led to downregulation of SNARE complex proteins and neurotransmitter transporters.

Behavioral deficits were linked to disrupted antioxidant defenses and neurotransmitter signaling.

Abstract

Background/Objectives: Tributyltin (TBT) remains a persistent aquatic contaminant with documented neurotoxic effects, yet the underlying mechanisms of its neurotoxicity remain poorly understood. Methods: We investigated the comprehensive molecular mechanisms of TBT-induced neurotoxicity in zebrafish (Danio rerio) through an integrated approach combining histopathological examination, metabolomics analysis, transcriptional profiling, and behavioral assays. Results: Histopathological analysis revealed significant TBT-induced damage to brain tissue architecture. Metabolomic profiling demonstrated that TBT exposure (500 ng/L) severely disrupted cellular energy metabolism, particularly the TCA cycle and purine/pyrimidine metabolism, while exhibiting hormetic responses at lower concentrations. Transcriptional analysis identified widespread downregulation of SNARE complex proteins and neurotransmitter transporters, indicating comprehensive deterioration of synaptic machinery. Conclusions: These molecular perturbations corresponded with systematic disruption of antioxidant defense mechanisms and neurotransmitter signaling pathways, establishing a direct mechanistic link to observed behavioral deficits. Our findings reveal a hierarchical cascade of molecular disruptions triggered by TBT exposure, bridging the critical gap between metabolic dysregulation and synaptic dysfunction. This mechanistic framework provides fundamental insights into the neurotoxicological impact of this widespread environmental contaminant, highlighting potential therapeutic targets for intervention.

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