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Two-dimensional Porcine Intestinal Organoids Reflecting the Physiological Properties of Native Gut
Published on: January 31, 2025
Ambient tonicity and intestinal cytochrome CYP3A
1Department of Pharmacology, University of Toronto, Ontario, Canada.
Expert Opinion on Drug Metabolism & Toxicology
|April 9, 2010
Summary
Osmotic pressure influences human CYP3A expression in the gut. The tonicity-sensitive transcription factor NFAT5 increases CYP3A in vitro, but its role in vivo remains unclear.
Area of Science:
- Pharmacology
- Gastroenterology
- Molecular Biology
Background:
- Human CYP3A expression in vitro is tonicity-dependent, suggesting a novel regulatory mechanism in intestinal epithelia.
- The gastrointestinal tract presents a dynamic osmotic environment influenced by dietary intake.
Purpose of the Study:
- To review the impact of the gastrointestinal osmotic environment on intestinal CYP3A expression and function.
- To highlight the role of the tonicity-sensitive transcription factor NFAT5.
Main Methods:
- Comprehensive literature searches were conducted using Medline via OVID.
- Searches covered reports from 1950 to November 7, 2009.
Main Results:
- An update on the osmotic environment in the GI tract and its effects on intestinal CYP3A.
- Emphasis on the osmosensitive transcription factor NFAT5 and its role in tonicity-dependent regulation.
Conclusions:
- In vitro hypertonicity increases CYP3A expression via NFAT5 transcriptional enhancement.
- NFAT5 activation in vivo post-prandially or with high-salt diets requires further investigation.
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