Inflammatory Bowel Disease: A Stressed "Gut/Feeling"

Abstract

Inflammatory bowel disease (IBD) is a chronic and relapsing intestinal inflammatory condition, hallmarked by a disturbance in the bidirectional interaction between gut and brain. In general, the gut/brain axis involves direct and/or indirect communication via the central and enteric nervous system, host innate immune system, and particularly the gut microbiota. This complex interaction implies that IBD is a complex multifactorial disease. There is increasing evidence that stress adversely affects the gut/microbiota/brain axis by altering intestinal mucosa permeability and cytokine secretion, thereby influencing the relapse risk and disease severity of IBD. Given the recurrent nature, therapeutic strategies particularly aim at achieving and maintaining remission of the disease. Alternatively, these strategies focus on preventing permanent bowel damage and concomitant long-term complications. In this review, we discuss the gut/microbiota/brain interplay with respect to chronic inflammation of the gastrointestinal tract and particularly shed light on the role of stress. Hence, we evaluated the therapeutic impact of stress management in IBD.

Keywords: IBD; brain; gastrointestinal tract; interplay; microbiota; stress.

Figure 1

The gut/microbiota/brain interplay and its interactions upon exposure to stress. Under conditions of psychological stress including lack of sleep and physical inactivity, the brain (HPA axis) stimulates the production of pro-inflammatory cytokines. This can result in increased intestinal permeability and altered gut microbiota. In addition, fat- and sugar-enriched foods, long-term usage of medicines, as well as genetic predisposition can directly affect the gut microbiota composition, and subsequently, intestinal permeability. Furthermore, personal habits, such as hygiene and smoking, can also have an impact on the gut microbiome. Altogether, the multitude of stress-related factors can perturb the gut/microbiota/brain interplay, which contributes to the development of IBD. Relevantly, several stress management techniques have been proven to greatly alleviate IBD symptoms and improve the quality of life of IBD patients. Given that the exact underlying mechanisms in the context of IBD are not yet fully understood, therapeutic options aimed at improving stress management deserve further investigation.