The role of alpha7 nicotinic acetylcholine receptors in inflammatory bowel disease: involvement of different cellular pathways

Introduction: Autonomic imbalance plays a pivotal role in the pathophysiology of inflammatory bowel diseases (IBD). The central nervous system (CNS) cooperates dynamically with the immune system to regulate inflammation through humoral and neural pathways. In particular, acetylcholine (Ach), the main neurotransmitter in the vagus nerve, decreases the production of pro-inflammatory cytokines through a mechanism dependent on the alpha 7 nicotinic Ach receptors (alpha 7nAChRs). Areas covered: Here, we review the evidence for involvement of the cholinergic anti-inflammatory pathway (CAP) in IBD. We also elaborate the role of alpha 7nAChRs and subsequent cellular pathways in CAP. Finally, we review potential therapeutic implications of modulators of these receptors. Expert opinion: Alpha7nAChR modulators possess both cognitive improving and anti-inflammatory properties. Although, these agents demonstrated therapeutic benefits in experimental models, their efficacy has not always been translated in clinical trials. Thus, development of more specific alpha 7nAChR ligands as well as more experimental studies and better controlled trials, especially in the field of IBD, are encouraged for a progress in this field.