Transport across Caco-2 monolayers of peptides arising from in vitro digestion of bovine milk proteins

• Published in: Food chemistry Vol. 139; no. 1-4; pp. 203 - 212
• Main Authors: Picariello, Gianluca, Iacomino, Giuseppe, Mamone, Gianfranco, Ferranti, Pasquale, Fierro, Olga, Gianfrani, Carmen, Di Luccia, Aldo, Addeo, Francesco
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15-08-2013; Elsevier
• Subjects: Animals; Bioactive peptides; Biological and medical sciences; Biological Transport; Caco-2 cell monolayers; Caco-2 Cells; Caseins - chemistry; Caseins - metabolism; Cattle; Cell Membrane - chemistry; Cell Membrane - metabolism; Cow’s milk allergy; Digestion; Food industries; Fundamental and applied biological sciences. Psychology; Gastrointestinal digestion; General aspects; Handling, storage, packaging, transport; Humans; Kinetics; Milk and cheese industries. Ice creams; Milk proteins; Milk Proteins - chemistry; Milk Proteins - metabolism; Models, Biological; Peptide uptake; Peptides - chemistry; Peptides - metabolism; Whey Proteins; Gastrointestinal digestion; Caco-2 cell monolayers; Milk proteins; Peptide uptake; Bioactive peptides; Cow’s milk allergy; Allergy; Monolayer; Cell culture; Peptides; Gastrointestinal; Cow's milk allergy; Milk protein; Ungulata; Immunopathology; Bovine; Digestive system; Gut; Digestion; In vitro; Uptake; Vertebrata; Mammalia; Cow milk; Artiodactyla; Transport
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2013.01.063

► Casein and whey proteins were in vitro digested and applied to Caco-2 monolayers. ► Resistant peptides able to translocate across monolayers were characterised. ► Minor amount of supposed bioactive peptides were detected. ► After digestion milk proteins almost completely lost the IgE-binging properties. ► β-Lg 127–135 is a possible “immune sensitising factors” in vivo.
The entire panel of peptides produced from caseins (CN) and whey proteins (WP) that survive in vitro sequential gastro-pancreatic digestion and translocate across monolayers of Caco-2 cells, used as a model of the intestinal epithelium, has been characterised by HPLC and mass spectrometry. Among the milk-derived bioactive peptides, only minor amounts of mono-phosphorylated peptides arising from αs1- and β-CN were detected. The absorption behaviour of two resistant β-lactoglobulin (β-Lg) domains, β-Lg 125–135 and β-Lg 40–60, was studied in detail using synthetic peptides. The IgE-binding properties of the digests recovered from the apical and basolateral monolayer compartments were evaluated by dot-blot, using the sera of milk allergic children (N=5). Outcomes indicated β-Lg 127–135 as a possible “immune sensitising factor” in vivo. The almost complete loss of the IgE-affinity of CN and WP after digestion points out the need to design in vivo experiments to track the metabolic fate of dietary proteins.