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Published on: November 15, 2013
Assessing the dynamics of nuclear glucocorticoid-receptor complex: adding flexibility to gene expression modeling
Anasuya Hazra1, Debra C DuBois, Richard R Almon
1Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, State University of New York, 565 Hochstetter Hall, Buffalo, NY 14260, USA.
Journal of Pharmacokinetics and Pharmacodynamics
|February 8, 2007
Summary
This study enhances a pharmacodynamic model for glucocorticoid receptor (GR) dynamics by incorporating physiological features. The improved model better predicts GR-mediated gene expression in rat liver following methylprednisolone (MPL) treatment.
Area of Science:
- Pharmacology
- Molecular Biology
- Systems Biology
Background:
- Glucocorticoid receptor (GR) signaling is crucial for cellular responses.
- Existing pharmacodynamic models require refinement for greater physiological relevance.
Purpose of the Study:
- To modify and enhance a fourth-generation pharmacodynamic model for GR dynamics.
- To incorporate in vitro and in vivo data for improved mechanistic understanding of GR signaling.
Main Methods:
- Retrospective analysis of existing GR and GR mRNA data in rats.
- Integration of in vitro kinetic data for steroid-receptor complex nuclear translocation.
- Validation using chronic methylprednisolone infusion studies in adrenalectomized rats.
Main Results:
- The modified model accurately describes GR and GR mRNA dynamics after single and dual methylprednisolone doses.
- In vitro receptor kinetics enabled characterization of pharmacogenomic effects on multiple genes.
- The model successfully predicted responses for early (CEBP-beta) and late (TAT) responsive genes.
Conclusions:
- The enhanced mechanistic model provides a more comprehensive understanding of GR dynamics.
- This model can be applied to characterize gene expression profiles mediated by glucocorticoids in the liver.
- The refined model improves predictions of receptor-mediated pharmacogenomic effects.
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