Claudin-related intestinal diseases.

Area of Science:

• Gastroenterology
• Cell Biology
• Immunology

Background:

• The human intestine possesses a vast absorptive surface (200 m²) lined by epithelial cells, crucial for nutrient absorption and barrier function.
• Tight junction (TJ) proteins, particularly claudins, maintain the paracellular barrier, regulating the passage of substances and defending against antigens.
• Dysregulation of claudins can lead to altered intestinal permeability, causing issues like malabsorption, diarrhea, and inflammatory responses.

Purpose of the Study:

• To review current knowledge on intestinal barrier dysfunction.
• To summarize claudin dysregulation in common gastrointestinal diseases.
• To highlight the role of claudins in diseases like IBD, celiac disease, and infectious enteropathies.

Main Methods:

• Literature review of studies on intestinal barrier function and claudin proteins.
• Analysis of claudin alterations in various gastrointestinal pathologies.
• Synthesis of findings related to disease mechanisms and clinical implications.

Main Results:

• Changes in claudin abundance or structure impact intestinal permeability.
• Claudin dysregulation is associated with decreased absorption, increased secretion (diarrhea), and heightened passage of macromolecules.
• Specific claudin alterations are implicated in inflammatory bowel disease, microscopic colitis, celiac disease, IBS, and infectious enteropathies.

Conclusions:

• Claudin proteins are critical components of the intestinal barrier.
• Dysfunctional claudins contribute significantly to the pathogenesis of numerous gastrointestinal diseases.
• Targeting claudin pathways may offer therapeutic strategies for intestinal disorders.