title: Claudins, dietary milk proteins, and intestinal barrier regulation.
abstract: The family of claudin proteins plays an important role in regulating the intestinal barrier by modulating the permeability of tight junctions. The impact of dietary protein on claudin biology has not been studied extensively. Whey proteins have been reported to improve intestinal barrier function, but their mechanism of action is not clear. Recent studies, however, have demonstrated increased intestinal claudin expression in response to milk protein components. Reviewed here are new findings suggesting that whey-protein-derived transforming growth factor β transcriptionally upregulates claudin-4 expression via a Smad-4-dependent pathway. These and other data, including limited clinical studies, are summarized below and, in the aggregate, suggest a therapeutic role for whey protein in diseases of intestinal barrier dysfunction, perhaps, in part, by regulating claudin expression.
authors.affiliation: Department of Allied Health Sciences, University of Connecticut, Storrs, Connecticut 06269-2101, USA. belinda.kotler@alumni.uconn.edu
authors.forename: Belinda M
authors.initials: BM
authors.lastname: Kotler
authors.forename: Jane E
authors.initials: JE
authors.lastname: Kerstetter
authors.forename: Karl L
authors.initials: KL
authors.lastname: Insogna
mesh_terms: D057167:Claudins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000502:physiology*; D008894:Milk Proteins / Q000378:metabolism*; D051901:Smad4 Protein / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D015854:Up-Regulation; D000067816:Whey Proteins
chemical_list: D057167:Claudins; D008894:Milk Proteins; C497796:SMAD4 protein, human; D051901:Smad4 Protein; D016212:Transforming Growth Factor beta; D000067816:Whey Proteins