Constipation-Predominant Irritable Bowel Syndrome Females Have Normal Colonic Barrier and Secretory Function

Area of Science:

• Gastroenterology
• Human Physiology
• Microbiome Research

Background:

• Irritable bowel syndrome with constipation (IBS-C) affects intestinal function.
• Previous research suggests potential alterations in intestinal barrier and secretory functions in IBS-C.
• Understanding these mechanisms is crucial for developing targeted therapies.

Purpose of the Study:

• To investigate the association between IBS-C and changes in intestinal barrier and secretory function in female patients.
• To compare in vivo and ex vivo measurements of intestinal permeability and secretion between IBS-C patients and healthy controls.
• To analyze colonic tight junction gene expression in relation to IBS-C.

Main Methods:

• Saccharide excretion assays (mannitol, lactulose) were performed to assess intestinal permeability.
• Measurements included duodenal and colonic mucosal barrier function (TMR, translocation assays) and secretion (short-circuit current).
• In vivo duodenal impedance, circulating endotoxins, and colonic tight junction gene expression were also evaluated.

Main Results:

• No significant differences were observed in colonic barrier function, duodenal impedance, plasma endotoxin levels, or colonic tight junction gene expression between IBS-C patients and controls.
• Ex vivo assessments of duodenal and colonic transmucosal resistance and particle flux showed no group differences.
• While colonic basal secretion was similar, basal duodenal secretion was significantly lower in IBS-C patients (P=0.05).

Conclusions:

• Female patients with IBS-C exhibit normal colonic barrier and secretory functions.
• A notable finding is the decreased basal duodenal secretion in IBS-C patients.
• These results suggest that colonic integrity is maintained in IBS-C, but duodenal secretory function may be impaired.