Epithelial expression and function of trypsin-3 in irritable bowel syndrome

Claire Rolland (1) , Alexandre Denadai-Souza (1) , Carla Cirillo (2) , Cintya Lopez (3) , Josue Obed Jaramillo (3) , Cléo Desormeaux (1) , Nicolas Cénac (1) , Jean-Paul Motta (1) , Muriel Larauche (4) , Yvette Taché (4) , Pieter Vanden Berghe (2) , Michel Neunlist (5) , Emmanuel Coron (5) , Sylvain Kirzin (6) , Guillaume Portier (6) , Delphine Bonnet (6) , Laurent Alric (6) , Stephen Vanner (3) , Céline Deraison Manuel (1) , Nathalie Vergnolle (1, 7)

1 IRSD - Institut de Recherche en Santé Digestive
2 Laboratory for Enteric Neuroscience (LENS), TARGID
3 Gastrointestinal Diseases Research Unit, General Hospital, Queen’s University School of Medicine
4 David Geffen School of Medicine [Los Angeles]
5 TENS - The Enteric Nervous System in gut and brain disorders [U1235]
6 Service Médecine Interne et immunologie clinique [CHU Toulouse]
7 Department of Physiology and Pharmacology

Objectives Proteases are key mediators of pain and altered enteric neuronal signalling, although the types and sources of these important intestinal mediators are unknown. We hypothesised that intestinal epithelium is a major source of trypsin-like activity in patients with IBS and this activity signals to primary afferent and enteric nerves and induces visceral hypersensitivity. Design Trypsin-like activity was determined in tissues from patients with IBS and in supernatants of Caco-2 cells stimulated or not. These supernatants were also applied to cultures of primary afferents. mRNA isoforms of trypsin (PRSS1, 2 and 3) were detected by reverse transcription-PCR, and trypsin-3 protein expression was studied by western blot analysis and immunohistochemistry. Electrophysiological recordings and Ca2+ imaging in response to trypsin-3 were performed in mouse primary afferent and in human submucosal neurons, respectively. Visceromotor response to colorectal distension was recorded in mice administered intracolonically with trypsin-3. Results We showed that stimulated intestinal epithelial cells released trypsin-like activity specifically from the basolateral side. This activity was able to activate sensory neurons. In colons of patients with IBS, increased trypsin-like activity was associated with the epithelium. We identified that trypsin-3 was the only form of trypsin upregulated in stimulated intestinal epithelial cells and in tissues from patients with IBS. Trypsin-3 was able to signal to human submucosal enteric neurons and mouse sensory neurons, and to induce visceral hypersensitivity in vivo, all by a protease-activated receptor-2-dependent mechanism. Conclusions In IBS, the intestinal epithelium produces and releases the active protease trypsin-3, which is able to signal to enteric neurons and to induce visceral hypersensitivity.

Mots clés: trypsin; intestinal epithelium

Mots clés: syndrome de bowel; hypersensibilité viscérale; protéase; trypsine; épithélium intestinal

Domaines: Hépatologie et Gastroentérologie

Claire Rolland, Alexandre Denadai-Souza, Carla Cirillo, Cintya Lopez, Josue Obed Jaramillo, et al.. Epithelial expression and function of trypsin-3 in irritable bowel syndrome. Gut, 2017, 66 (10), pp.1767-1778. ⟨10.1136/gutjnl-2016-312094⟩. ⟨hal-01604269⟩