Neuroimmune Cross Talk in the Gut. Neuroendocrine and neuroimmune pathways contribute to the pathophysiology of irritable bowel syndrome

Dervla O'Malley

Irritable bowel syndrome (IBS) is a common disorder characterized by recurrent abdominal pain, bloating and disturbed bowel habit, symptoms which impact on the quality of life of sufferers. The pathophysiological changes underlying this multifactorial condition are complex and include increased sensitivity to luminal and mucosal factors which result in altered colonic transit and visceral pain. Moreover, dysfunctional communication in the bidirectional signaling axis between the brain and the gut, which involves efferent and afferent branches of the peripheral nervous systems, circulating endocrine hormones and local paracrine and neurocrine factors, including immune and perhaps even microbial signaling molecules have a role to play in this disorder. This mini-review will examine recent advances in our understanding of the pathophysiology of IBS and assess how crosstalk between hormones, immune and microbe-derived factors and their neuromodulatory effects on peripheral nerves may underlie IBS symptomatology.