Molecular size of collagen peptide reverses the permeability of Caco-2 cells.

Intestinal permeability to size-classified fish collagen peptides (FCPs) was examined using Caco-2 monolayers. Minimum-sized FCPs were most efficiently transported across the Caco-2 monolayers. Permeability depended on peptide size. It was independent of the H(+)-coupled peptide transport system but was associated with tight junction permeability, suggesting that the paracellular pathway is responsible for transepithelial transport of collagen peptides.