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Updated: Jun 21, 2026
05:10
Three-dimensional Quantification of Intestinal Mucus Using Whole-mount Tissue Imaging
Published on: September 12, 2025
Gastroduodenal mucosal defense.
Hamed Nayeb-Hashemi1, Jonathan D Kaunitz
1aDepartment of Internal Medicine, UCLA Medical Center, USA bGreater Los Angeles Veteran Affairs Healthcare System, WLAVA Medical Center, Los Angeles, California, USA.
Current Opinion in Gastroenterology
|August 6, 2009
Summary
The gastroduodenum employs bicarbonate secretion and other mechanisms to resist injury from factors like NSAIDs and H. pylori. Understanding these defenses reveals potential therapeutic targets for better treatments.
Area of Science:
- Gastroenterology
- Immunology
- Pharmacology
Background:
- The gastroduodenum possesses inherent defense mechanisms against various injurious agents.
- Factors such as gastric acid, NSAIDs, and H. pylori can compromise these defenses.
Purpose of the Study:
- To review recent advances in understanding gastroduodenal injury resistance mechanisms.
- To discuss factors contributing to the failure of these defensive pathways.
Main Methods:
- Review of current scientific literature on gastroduodenal physiology and pathology.
- Analysis of molecular and cellular mechanisms underlying mucosal defense and injury.
Main Results:
- Duodenal bicarbonate secretion, regulated by anion exchangers and estrogens, is a key defense.
- NSAID-induced gastric damage involves toll-like receptor signaling.
- Portal hypertensive gastropathy increases oxidative stress via impaired ERK1/2 phosphorylation.
- H. pylori-induced ulcers are linked to insufficient regulatory T cell responses.
Conclusions:
- Advances in understanding gastroduodenal defense mechanisms offer novel therapeutic targets.
- This knowledge facilitates the development of safer and more effective gastrointestinal therapies.
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