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01:29
The Number e as a Limit
Published on: January 12, 2026
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Loss of detoxification in inflammatory bowel disease: dysregulation of pregnane X receptor target genes
Thomas Langmann1, Christoph Moehle, Richard Mauerer
1Institute of Clinical Chemistry and Laboratory Medicine, University of Regensburg, Regensburg, Germany.
Gastroenterology
|July 6, 2004
Summary
Reduced expression of detoxification genes and pregnane X receptor (PXR) in ulcerative colitis may impair gut barrier function. This suggests PXR dysregulation contributes to UC pathophysiology.
Area of Science:
- Gastroenterology
- Molecular Biology
- Pharmacology
Background:
- Intestinal barrier integrity relies on efflux transporters crucial for xenobiotic and bacterial defense.
- Global gene expression profiling was conducted in ulcerative colitis (UC) and Crohn's disease patients.
Purpose of the Study:
- To investigate the role of detoxification and epithelial membrane integrity genes in inflammatory bowel disease (IBD).
- To identify specific gene expression changes in UC and Crohn's disease.
Main Methods:
- DNA microarray analysis and pathway analysis of mucosal biopsies from IBD patients and controls.
- Real-time RT-PCR validation in larger patient cohorts and intestinal cell lines.
Main Results:
- Coordinately down-regulated detoxification and defense genes were identified in the colon of UC patients, linked to pregnane X receptor (PXR) targets.
- Significant reduction in ABCB1 (MDR1) and PXR mRNA expression observed in UC colons, but not in Crohn's disease.
- PXR expression was not affected by tumor necrosis factor alpha stimulation in intestinal cell lines.
Conclusions:
- A disease- and tissue-specific decrease in detoxification enzymes and ABC transporters suggests a loss of PXR expression in UC.
- Dysregulation of xenobiotic metabolism and PXR activity in the gut likely contributes to UC pathophysiology.
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