Transepithelial transport across Caco-2 cell monolayers of antihypertensive egg-derived peptides. PepT1 -mediated flux of Tyr-Pro-lle

This paper examines the in vitro transepithelial transport of antihypertensive peptides derived from egg proteins using Caco-2 cell monolayers. Ovokinin (FRADHPFL) was absorbed intact through the Caco-2 cell epithelium, although it was also susceptible to the action of brush-border aminopeptidases that yielded shorter fragments prior to their transport. The tripeptide YPI was resistant to cellular peptidases and transported through the monolayer, what suggests that the reduction in systemic blood pressure caused by this peptide may be mediated by effects at tissue level. Its pathway for transepithelial absorption was examined using inhibitors of the different mechanisms for oligopeptide transport in the intestinal tract. The main route involved in the transepithelial flux of YPI is probably the peptide H+-coupled transporter PepTl. These results highlight the potential of antihypertensive peptides to be used in the formulation of functional foods.