Genetic Determinism of Epithelial Barrier Defects in Irritable Bowel Syndrome (PROTIBS)

Centre Hospitalier Universitaire de Nice

Status: Withdrawn

Conditions: Irritable Bowel Syndrome (IBS)

Treatments: Genetic: Analysis on colorectal biopsy

Study type: Interventional

Funder types: Other

Identifiers

NCT02841878

14-PP-20

Details and patient eligibility

About

Irritable bowel syndrome (IBS) profoundly affects the quality of life. Mucosal micro-inflammation, epithelial permeability disorder and proteases activity increase have been demonstrated in the patients' gastrointestinal tract. Protease activity increase could be subjected to a genetic determinism (decrease in proteases inhibitors genes expression). Objectives: 1/ To study relations between proteases activity (in stool and colonic biopsies supernatants), proteases inhibitors genes expression and mucosal cellular infiltrate (IBS patients and healthy subjects). 2/ Establishing a correlation between proteases activity, mucosal micro-inflammation and symptoms. 3/ To evaluate proteases inhibitors therapeutic potential. Expected results: 1/ Decreased expression of proteases inhibitors genes in subjects with IBS. 2/ Correlation of symptoms with proteases activity intensity. 3/ Demonstration of restorative potential of proteases inhibitors.

Full description

Irritable bowel syndrome (IBS) is the first reason for consultation in gastroenterology and his prevalence reach 5% of the general population. IBS is characterized by abdominal discomfort, diarrhea or constipation and decreased quality of life.

Recent facts on IBS pathophysiology show association between mucosal immunity activation (mast cells and their proteases) and epithelial permeability disorder. Permeability disorder can be reproduced by application of colonic biopsies cultures supernatants on in-vitro cell cultures. In parallel, tight junctions proteins mRNA (ZO-1, Occludin) decrease is observed ex-vivo in biopsies and in-vitro.

Gut bacterial proteases (cystein and serin proteases) may also play a role. In human, proteases activity is correlated with IBS symptoms severity. Proteases activity increase (cystein and serin proteases) is poorly understood, and this increase could be subjected to a genetic determinism (decrease in proteases inhibitors genes expression - Serpin A1/E1).

Objectives: 1/ To study relations between proteases activity (in stool and colonic biopsies supernatants), proteases inhibitors genes expression and mucosal cellular infiltrate (IBS patients and healthy subjects). 2/ Establishing a correlation between proteases activity, mucosal micro-inflammation and symptoms. 3/ To evaluate proteases inhibitors therapeutic potential.

Method: Subjects will be recruited in gastroenterology consultation. IBS patients will answer to Rome III criteria. Patients coming for screening colonoscopy will be defined as healthy subjects.

Colonic biopsies will be sent in real time to the research laboratory (EA 6302) for supernatants collecting, mRNA expression studies (Serpins, ZO-1, occludin, cytokines), proteases activity / permeability measurements and proteases inhibitors reversibility tests. Histologic study will also be performed.

Expected results: 1/ Decreased expression of proteases inhibitors genes in subjects with IBS. 2/ Correlation of symptoms with proteases activity intensity. 3/ Demonstration of restorative potential of proteases inhibitors.

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria:

• Patient with irritable bowel syndrome (IBS), defined by Rome III criteria (patient group)
• Patients coming for screening colonoscopy (control group)

Patients exclusion criteria :

• Active inflammatory bowel disease
• Infectious bowel disease or other cause that could explain digestive symptoms

Healthy subjects inclusion criteria :

• Patients coming for screening colonoscopy without inflammatory bowel disease or IBS

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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0 participants in 1 patient group

analysis on colorectal biopsy

Other group

Description:

* Proteases activity (cystein and serin proteases) * Proteases inhibitors genes expression (Serpins A1 / E1) * Colonic biopsies permeabilityTight junctions genes expression * Cytokines genes expression (TNFalpha, interleukines) * Cellularity on histologic sections

Treatment:

Genetic: Analysis on colorectal biopsy