Developing and applying the adverse outcome pathway concept for understanding and predicting neurotoxicity

Area of Science:

• Toxicology
• Risk Assessment
• Neuroscience

Background:

• The Adverse Outcome Pathway (AOP) concept offers a new paradigm for regulatory toxicology and risk assessment.
• AOPs describe a sequence of key events, from molecular initiation to adverse outcomes, triggered by stressors.
• Understanding these pathways is crucial for predicting chemical effects and assessing neurotoxicity.

Purpose of the Study:

• To introduce the principles of Mode of Action (MOA) and AOPs in the context of neurotoxicity.
• To summarize potential AOPs for developmental and adult neurotoxicity.
• To discuss the application of AOPs in Integrated Approaches to Testing and Assessment (IATA).

Main Methods:

• Review and synthesis of existing knowledge on neurotoxicity pathways.
• Application of the AOP framework to describe sequences of key events.
• Consideration of assessment strategies for AOPs.

Main Results:

• AOPs provide a structured way to link molecular initiating events to adverse outcomes.
• Potential AOPs for neurotoxicity, including developmental and adult effects, were identified.
• The utility of AOPs for developing mechanistically informed IATA was discussed.

Conclusions:

• AOPs are valuable tools for understanding chemical-induced neurotoxicity.
• The AOP concept facilitates structure-activity relationship analysis and predictive modeling.
• AOPs support the development of advanced, mechanistically based testing and assessment strategies.