Related Experiment Video
Updated: Jun 13, 2026
07:39
Basic Three-Dimensional (3D) Intestinal Model System with an Immune Component
Published on: September 1, 2023
The Intestinal Barrier: A Multilayered Gatekeeper Against Systemic Disease
Jun Wakabayashi1,2, Katsunori Kimura1,2, Takeshi Kawauchi1,3
1Department of Adaptive and Maladaptive Responses in Health and Disease, Graduate School of Medicine, Kyoto University, Kyoto, Japan, kyoto-u.ac.jp.
International Journal of Microbiology
|June 12, 2026
Summary
The intestinal barrier, crucial for nutrient absorption and pathogen defense, comprises four layers. Its disruption, or "leaky gut," can trigger systemic inflammation and disease, necessitating effective restoration strategies.
Area of Science:
- Gastroenterology and Immunology
- Physiology
- Microbiology
Background:
- The intestine balances nutrient absorption with defense against pathogens via a multilayered barrier.
- This barrier consists of physical, chemical, microbiological, and immunological components.
- Disruption leads to increased intestinal permeability ('leaky gut'), allowing systemic translocation.
Purpose of the Study:
- To delineate the four layers of the intestinal barrier.
- To explore the systemic consequences of intestinal barrier disruption.
- To summarize current assessment methods and therapeutic strategies for barrier restoration.
Main Methods:
- Review of existing literature on intestinal barrier structure and function.
- Analysis of regional differences in barrier integrity between small and large intestines.
- Synthesis of data on systemic inflammatory responses triggered by barrier dysfunction.
Main Results:
- Barrier dysfunction varies regionally (small vs. large intestine) due to differences in epithelium, mucus, and microbiota.
- Disrupted intestinal barrier triggers inflammation in distant organs (liver, brain, kidneys, muscles).
- Current therapeutic strategies include diet, microbiota modulation, postbiotics, and lifestyle changes.
Conclusions:
- Understanding the intestinal barrier's complexity is vital for preventing and treating systemic diseases.
- Restoring barrier integrity is key to strengthening defense against pathogens and maintaining physiological function.
- Novel therapeutic approaches are needed to address the systemic impact of leaky gut.
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