The oligopeptide transporter (Pept-1) in human intestine: biology and function.
Level 5 - mechanism / opinion, no new human data
Narrative review of bench, cell-line, and mechanistic data without primary clinical trial data.
PubMed 9207295 · doi:10.1016/s0016-5085(97)70112-4
What was done
This review summarized the molecular cloning, structural features, transport mechanism, cellular regulation (using Caco-2 human intestinal cell models), and pharmacological relevance of the human intestinal oligopeptide transporter Pept-1.
What was found
Pept-1 is predicted to be a 78,810-dalton protein with 708 amino acid residues and 12 membrane-spanning domains. It transports dipeptides and tripeptides via proton binding and an inside-negative membrane potential, while excluding free amino acids and longer peptides. In Caco-2 cell studies, insulin increased dipeptide transport by promoting transporter translocation from a cytoplasmic pool, whereas cholera toxin inhibited transport via elevated intracellular cyclic AMP. The abstract provides no quantitative effect sizes or statistical metrics.
Why it matters
Understanding Pept-1 mechanisms provides a biological foundation for designing peptide-based enteral nutrition formulations and optimizing oral delivery of peptidomimetic pharmaceuticals, such as beta-lactam antibiotics.
Limits
The abstract describes a narrative review combining expression cloning, in vitro cell culture (Caco-2), and mechanistic models; no clinical trials, patient cohorts, sample sizes, or quantitative error bounds are reported.
Cited by
- supports Di- and tripeptides can be orally bioavailable if they have the appropriate conformation and size.