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Hormetic mechanisms

Edward J Calabrese1

  • 1Department of Public Health, Environmental Health Sciences, University of Massachusetts, Amherst, MA 01003, USA. edwardc@schoolph.umass.edu

Critical Reviews in Toxicology
|July 24, 2013
PubMed

Insights

This study extensively documents hormetic dose responses, revealing consistent quantitative features across diverse agents and pathways. These findings highlight biological plasticity and offer insights for drug discovery and risk assessment.

Area of Science:

  • Toxicology
  • Pharmacology
  • Biochemistry

Background:

  • Hormesis describes a non-monotonic dose-response relationship.
  • Understanding the underlying mechanisms is crucial for its application.

Purpose of the Study:

  • To extensively document the mechanisms of hormetic dose/concentration responses.
  • To investigate receptor and cell signaling pathways involved in hormesis.
  • To explore the generalizability and potential applications of hormetic responses.

Main Methods:

  • Systematic review and documentation of mechanisms for over 100 agents.
  • Analysis of nearly 400 dose/concentration responses across various chemical classes.
  • Inclusion of both in vitro and in vivo models.

Main Results:

  • Identified mechanisms primarily mediated by receptor and cell signaling pathways.
  • Documented hormetic responses across diverse cell types and endpoints.
  • Observed consistent quantitative features of hormetic responses regardless of the model or agent.

Conclusions:

  • Hormetic dose responses exhibit remarkable generalizability across biological contexts.
  • The magnitude of hormetic response reflects biological plasticity.
  • Findings have significant implications for drug discovery, efficacy assessment, and risk assessment.

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