title: Transepithelial transport and stability in blood serum of angiotensin-I-converting enzyme inhibitory dipeptides.
abstract: The dipeptides Ala-Trp, Val-Phe, and Val-Tyr inhibit the angiotensin-I-converting enzyme. They are encrypted within the primary sequences of different food proteins, e.g. milk proteins. The angiotensin-I-converting enzyme inhibitory potency of these synthetic dipeptides was quantified using a spectrophotometric assay. The dipeptides showed no adverse effects on differentiated Caco-2 cells (model for human intestinal epithelium), as confirmed by transepithelial electrical resistance, microscopy and the activity of the brush-border enzyme dipeptidyl aminopeptidase IV. Furthermore, the transport of these bioactive dipeptides through intact Caco-2 monolayers and their stability to incubation in human blood serum has been demonstrated for the first time. Low molecular mass peptides represent the minimal structures required for angiotensin-I-converting enzyme inhibition which have a high potential bioavailability. Therefore, they may act as target peptides in enriched hydrolysates for the preparation of an angiotensin-I-converting enzyme inhibitory peptide and for the use in special formulations as functional foods/foods of specified health use.
authors.affiliation: Max-Rubner-Institute (MRI), Federal Research Institute of Nutrition and Food-Location Kiel, Department of Safety and Quality of Milk and Fish Products, Hermann-Weigmann-Str. 1, D-24103 Kiel, Germany.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Pentzien
authors.forename: Hans
authors.initials: H
authors.lastname: Meisel
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000097:blood / Q000494:pharmacology*; D001692:Biological Transport / Q000187:drug effects; D018938:Caco-2 Cells / Q000187:drug effects; D004151:Dipeptides / Q000097:blood / Q000494:pharmacology*; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology*; D006626:Hippurates / Q000378:metabolism; D006801:Humans; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D004151:Dipeptides; D006626:Hippurates; C042807:DPP4 protein, human; D018819:Dipeptidyl Peptidase 4; D007703:Peptidyl-Dipeptidase A; C030514:hippuric acid