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Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Published on: November 15, 2013
Pregnane xenobiotic receptors and their effect on drug elimination from the organism
M Šíma1, I Netíková1, O Slanař2
1Institute of Pharmacology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic.
Abstract:
Nuclear receptors are intracellular proteins which, having been activated by their more or less specific ligands, regulate (usually increase) the transcription of target genes. They thus participate in a regulation of a number of physiologic functions. Some of them - especially pregnane xenobiotic receptors - serve primarily as protection of the organism from the xenobiotic intoxication. This is because many xenobiotics activate their function which consists in increasing the gene expression of enzymes involved in the metabolism of xenobiotics and detoxication drug transporters. Clarification of these mechanisms enabled the understanding of the substance of many drug-drug interactions observed in the clinical practice. Polymorphism of the nuclear receptors appears to be one of the causes of the interindividual variability in response to drug administration.
Insights
Nuclear receptors regulate gene transcription for physiologic functions. Pregnane xenobiotic receptors protect against toxins by boosting metabolism and detoxifying enzymes, impacting drug interactions and variability.
Area of Science:
- Molecular Biology
- Pharmacology
- Toxicology
Background:
- Nuclear receptors are intracellular proteins that regulate gene transcription upon ligand activation.
- They play crucial roles in various physiological functions and organism protection.
- Pregnane xenobiotic receptors (PXRs) are key in defending against xenobiotic intoxication.
Purpose of the Study:
- To elucidate the mechanisms by which nuclear receptors, particularly PXRs, mediate xenobiotic metabolism and detoxification.
- To understand the role of these mechanisms in drug-drug interactions.
- To explore the contribution of nuclear receptor polymorphism to interindividual variability in drug response.
Main Methods:
- Analysis of gene transcription regulation by nuclear receptors.
- Investigation of xenobiotic activation pathways.
- Study of drug metabolism enzyme and transporter gene expression.
- Examination of clinical data on drug-drug interactions and patient responses.
Main Results:
- Xenobiotics activate nuclear receptors, increasing the expression of genes involved in xenobiotic metabolism and drug transporters.
- These mechanisms clarify the basis of numerous observed drug-drug interactions.
- Genetic variations (polymorphisms) in nuclear receptors contribute to differing individual responses to medications.
Conclusions:
- Nuclear receptors are critical regulators of xenobiotic metabolism and detoxification pathways.
- Understanding nuclear receptor function is essential for predicting and managing drug-drug interactions.
- Nuclear receptor polymorphism is a significant factor in personalized medicine and pharmacogenomics.
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