The role of short-chain fatty acid metabolism in colonic disorders.

During the past decade it has become evident that colonic mucosal metabolism is more complex than previously suspected. Luminal short-chain fatty acids (SCFAs) are recognized as an essential fuel source for colonocytes, particularly in the distal colon. Their absence may explain the development of diversion colitis; however, this has not been confirmed by clinical trials. The histologic, endoscopic, and metabolic similarities between diversion colitis and ulcerative colitis suggest that a nutritional SCFA deficiency state may play a role in the pathogenesis of these disorders. Diversion colitis and continent urinary diversion, utilizing distal and proximal colon reservoirs, provide in vivo models to study normal colonic mucosa in circumstances of reduced intraluminal SCFA concentrations and altered luminal effluent. Further studies utilizing these models would enhance our understanding of the regional differences in mucosal cell metabolism and adaptability and, hopefully, provide therapeutic alternatives for the management of colonic disorders. The welfare of colonic mucosa, as it relates to SCFA metabolism, awaits another exciting decade of investigation.