• GUT INFLAMMATION
• NUTRITION
• BRAIN/GUT INTERACTION

Inflammatory bowel diseases (IBD) comprise a spectrum of chronic intestinal inflammatory diseases, mainly ulcerative colitis (UC) and Crohn’s disease (CD), with an increasing incidence worldwide.1 2 Scientific efforts and technological advances led to a profound understanding of IBD pathophysiology, helping to recognise the complex nature and heterogeneity of the IBD spectrum. In recent years, IBD has been increasingly appreciated as a systemic disease, associated with disorders affecting various organs of the body. Moreover, the complex relationship between the gut and the central nervous system (CNS) (termed ‘the gut-brain axis’) is substantially being investigated, exploring the potential causal link between many intestinal and neurological diseases.3

Several factors might explain the remarkable connection of the gut, and in particular IBD, with neurological diseases. First, chronic intestinal inflammation might damage the CNS through a systemic inflammatory response but also by dysregulating peripheral neurons in the gut.4 5 Second, disturbed interactions between luminal factors in the gut—particularly microorganisms and their metabolites—the enteric nervous system and the CNS are implicated in IBD, which impair neuron function in the CNS.6 Third, pathophysiological traits and disease mechanisms might be shared between IBD and neurologic diseases, as suggested earlier in the case of Parkinson’s disease.7

In Gut, Erkert et al …