Hypoxia-induced intestinal barrier changes in balloon-assisted enteroscopy

Area of Science:

• Gastroenterology
• Cell Biology
• Microbiology

Background:

• Balloon-assisted enteroscopy (BAE) is a deep endoscopy technique using balloons.
• BAE may cause gut tissue hypoxia and potential barrier dysfunction.
• The effects of BAE-induced hypoxia on intestinal barriers are not fully understood.

Purpose of the Study:

• To investigate bacterial translocation after BAE in patients.
• To model BAE-induced hypoxia in mice and assess its impact on the gut barrier.
• To determine the effects of short- and long-term hypoxia on epithelial permeability.

Main Methods:

• Prospective patient study with microbiological analysis of blood samples before and after BAE.
• Murine model of colonic balloon distension to evaluate tissue hypoxia and gut permeability.
• In vitro study using Caco-2 cells exposed to varying durations of hypoxia.

Main Results:

• Bacterial DNA was detected in 30.8% of patients post-BAE, with increased endotoxaemia but no sepsis.
• Colonic balloon distension in mice induced transient hypoxia and altered gut permeability.
• Short-term hypoxia (5-20 min) fortified epithelial tight junctions, while long-term hypoxia disrupted them.

Conclusions:

• BAE can lead to transient bacteraemia without clinical sepsis.
• Short-term hypoxia during BAE may protect the gut barrier.
• Prolonged balloon distension in BAE risks gut barrier dysfunction due to sustained hypoxia.