Grant: Operating Grant - PA: Regional Partnership Program - Newfoundland and Labrador

Dietary protein is taken up by absorptive cells in the gut after the digestive process breaks it down into free amino acids and small protein fragments called peptides. Free amino acids are absorbed by specific amino acid transport systems, whereas thousands of types of small peptides are absorbed by one transporter called PepT1. In situations when the gut is injured, such as during infection or after surgery, there is evidence that the absorption of dietary protein as peptides is preserved, while capacity to absorb single amino acids declines. One of the objectives of this research program is to determine if we can take advantage of this peptide transport system by feeding specific dipeptides that are nutritionally important, and may stimulate expression of greater amounts of the PepT1 transporters on the absorptive surface of cells of the gut. This may enhance the recovery of the injured small intestine by improving the nutritional status of the individual. Alternatively, PepT 1 also transports pro-inflammatory proteins that are released by bacteria in the gut. As such, more PepT1 may be harmful to the damaged intestine. Thus, a second objective of this research is to investigate the interactions between dietary peptides, bacterial peptides, and PepT1.