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Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
10:51

Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists

Published on: November 16, 2013

Drug-activated nuclear receptors CAR and PXR

Paavo Honkakoski1, Tatsuya Sueyoshi, Masahiko Negishi

  • 1Department of Pharmaceutics, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.

Annals of Medicine
|June 26, 2003
PubMed

Insights

Drug metabolism and elimination involve cytochrome P450 enzymes, regulated by nuclear receptors like constitutive androstane receptor (CAR) and pregnane X receptor (PXR). Understanding this induction is key for drug research and development.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Biochemistry

Background:

  • Drug metabolism and elimination are primarily mediated by cytochrome P450 (CYP) enzymes, conjugative enzymes, and transport proteins.
  • Induction of drug metabolism, through gene expression activation, is a critical aspect of drug elimination.
  • Nuclear receptors, specifically constitutive androstane receptor (CAR) and pregnane X receptor (PXR), are known regulators of this induction process.

Purpose of the Study:

  • To review the fundamental properties of CAR and PXR, including their ligands and target genes.
  • To elucidate the mechanisms underlying drug metabolism induction mediated by these nuclear receptors.
  • To discuss the implications of nuclear receptor-mediated induction for the field of drug research.

Main Methods:

  • Literature review focusing on the roles of CAR and PXR in drug metabolism.
  • Analysis of existing data on nuclear receptor activation, gene expression, and drug response.
  • Synthesis of information regarding the molecular mechanisms of induction.

Main Results:

  • CAR and PXR are key drug-activated nuclear receptors that regulate the expression of genes involved in drug metabolism and transport.
  • These receptors bind to specific ligands and activate downstream signaling pathways leading to increased metabolic enzyme activity.
  • The induction process mediated by CAR and PXR significantly influences drug efficacy and toxicity.

Conclusions:

  • Nuclear receptors CAR and PXR play a pivotal role in the induction of drug metabolism.
  • Understanding the mechanisms of CAR/PXR-mediated induction is essential for optimizing drug therapy and minimizing adverse drug reactions.
  • This knowledge has significant implications for drug discovery, development, and personalized medicine.

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