Mast cells play an important role in many chronic inflammatory states. For Crohn and colitis various experimental studies support the use of the mast cell modulator palmitoylethanolamide. As this is a widely available foodsupplement this therapeutic compound should be more often considered.
Cancer patients treated with radiotherapy may develop bowel complications resembling Crohn’s disease and ulcerative colitis due to mast cell hyperplasia and activation in rectal tissue. To investigate the specific role played by mast cells, Blirando et al (Am J Pathol 2011, 178:640–651) induced experimental radiation proctitis in a mast cell-deficient (Wsh/Wsh) mouse model. Irradiated control rodent rectum showed mast cell hyperplasia, whereas Wsh/Wsh mice exhibited tissue protection associated with increased tissue neutrophil influx and expression of several inflammatory mediators immediately following radiation exposure. Expression of chymase, tryptase, and histamine by mast cells increased proliferation and migration of human primary colonic smooth muscle cells, as well as their secretion of proinflammatory molecules. Mast cells may thus disrupt neutrophil-mediated tissue protection, thereby perpetuating colonic wall inflammation and damage.