Is metabolic stress a common denominator in inflammatory bowel disease?

Ida Schoultz, Johan D. Söderholm, Derek M. McKay

The enteric epithelium represents the major boundary between the outside world and the body, and in the colon it is the interface between the host and a vast and diverse microbiota. A common feature of inflammatory bowel disease (IBD) is decreased epithelial barrier function, and while a cause-and-effect relationship can be debated, prolonged loss of epithelial barrier function (whether this means the ability to sense bacteria or exclude them) would contribute to inflammation. While there are undoubtedly individual nuances in IBD, we review data in support of metabolic stress--that is, perturbed mitochondrial function--in the enterocyte as a contributing factor to the initiation of inflammation and relapses in IBD. The postulate is presented that metabolic stress, which can arise as a consequence of a variety of stimuli (e.g., infection, bacterial dysbiosis, and inflammation also), will reduce epithelial barrier function and perturb the enterocyte-commensal flora relationship and suggest that means to negate enterocytic metabolic stress should be considered as a prophylactic or adjuvant therapy in IBD.