Transport Across Caco-2 Cell Monolayer and Sensitivity to Hydrolysis of Two Anxiolytic Peptides from αs1-Casein, α-Casozepine, and αs1-Casein-(f91–97): Effect of Bile Salts

• Published in: Journal of agricultural and food chemistry 2011-11, Vol.59 (22), p.11956-11965
• Main Authors: Cakir-Kiefer, Céline, Miclo, Laurent, Balandras, Frédérique, Dary, Annie, Soligot, Claire, Roux, Yves Le
• Format: Article
• Language: English
• Subjects: alphaS1-casein; bile; bile salts; Bioactive Constituents; Biological and medical sciences; Feeding. Feeding behavior; Food engineering; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Handling, storage, packaging, transport; human cell lines; hydrolysis; intestinal mucosa; Life Sciences; peptidases; peptides; rats; swine; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf202890e

α-Casozepine and f91–97, peptides from αs1-casein, display anxiolytic activity in rats and may have to cross the intestinal epithelium to exert this central effect. We evaluated their resistance to hydrolysis by the peptidases of Caco-2 cells and their ability to cross the cell monolayer. To mimic physiological conditions, two preparations of bile salts were used in noncytotoxic concentrations: porcine bile extract and an equimolar mixture of taurocholate, cholate, and deoxycholate. The presence and composition of bile salts appeared to modulate the peptidase activities of the Caco-2 cells involved (i) in the hydrolysis of α-casozepine, leading to much higher formation of fragments f91–99, f91–98, and f91–97, and (ii) in the hydrolysis of f91–97, leading to lower degradation of this peptide. Transport of α-casozepine across Caco-2 monolayer increased significantly, in the presence of bile extract, and of fragment f91–97, in the presence of bile salts.