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A Gut-on-a-Chip Model to Study the Gut Microbiome-Nervous System Axis
Published on: July 28, 2023
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The Oral-Gut Axis: Bidirectional Interactions Between Microbiome and Diseases.
Shinya Ebihara1, Nobuhiko Kamada1,2,3,4
1Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA.
Journal of Periodontal Research
|May 5, 2026
Summary
Oral bacteria in the gut, termed "gut oralization," contribute to gastrointestinal disorders like inflammatory bowel disease and colorectal cancer. Targeting the oral-gut axis may offer new therapeutic strategies for these conditions.
Area of Science:
- Microbiology
- Gastroenterology
- Oral Medicine
Background:
- Oral microorganisms are increasingly found in the gut lumen and mucosa of patients with gastrointestinal disorders.
- This phenomenon, known as "gut oralization," is implicated in the pathogenesis of inflammatory bowel disease and colorectal cancer.
Purpose of the Study:
- To review the mechanisms by which oral bacteria colonize the gut.
- To explore the role of the oral-gut microbial axis in gastrointestinal disease.
- To highlight potential therapeutic strategies targeting this axis.
Main Methods:
- Review of clinical and experimental evidence.
- Examination of bacterial traits facilitating gut colonization.
- Analysis of host and environmental factors influencing oral bacteria translocation.
Main Results:
- Oral pathobionts possess specialized strategies, including adhesion systems and metabolic adaptations, to colonize the gastrointestinal tract.
- Altered gut environments and host vulnerability facilitate ectopic colonization by oral bacteria.
- Bidirectional interactions between oral bacteria and the gut contribute to disease pathogenesis.
Conclusions:
- Gut oralization is a significant factor in gastrointestinal disease development.
- Targeting the oral-gut microbial axis presents a promising therapeutic avenue for chronic gastrointestinal disorders.
- Understanding these interactions can inform novel prevention and treatment strategies.
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