title: Effect of molecular weight on the transepithelial transport and peptidase degradation of casein-derived peptides by using Caco-2 cell model.
abstract: The transepithelial transport routes of casein-derived peptides with different molecular weights (MWs) were investigated using a Caco-2 cell monolayer. The peptidase hydrolysis during transport was also studied. The results indicate that the paracellular route was the main pathway for F1 (1600-1300Da) and F2 (1000-500Da), and the bioavailabilities were 10.66% and 9.54%, respectively. Peptidase hydrolysis results reveal that brush-border peptidases (BBPs) as well as some other peptidases were responsible for peptide degradation in the paracellular route. The maximum hydrolysis rate of the former was 6.91 and 5.59μM Gly/min for the latter. However, PepT1 was involved in the transport of F3 (<500Da) and its bioavailability was 16.23%. BBPs were the main peptidases involved in the PepT1 transport and the maximum hydrolysis rate was 11.4μM Gly/min. Furthermore, we found that the amino acid sequence of di- and tripeptides might affect their bioavailabilities significantly.
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; Beijing Higher Institution Engineering Research Center of Animal Product, Beijing 100083, China. Electronic address: libo@cau.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Li
mesh_terms: D001682:Biological Availability; D001692:Biological Transport; D018938:Caco-2 Cells; D002364:Caseins / Q000493:pharmacokinetics*; D006801:Humans; D006868:Hydrolysis; D008871:Microvilli / Q000378:metabolism; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism*; D000074011:Peptide Transporter 1; D010455:Peptides / Q000493:pharmacokinetics*; D027981:Symporters / Q000378:metabolism
chemical_list: D002364:Caseins; D000074011:Peptide Transporter 1; D010455:Peptides; C082186:SLC15A1 protein, human; D027981:Symporters; D010447:Peptide Hydrolases
keywords: Bioavailability; Brush-border peptidase (BBP); Casein peptide; Hydrolysis; Molecular weight (MW); Transepithelial transport