Claudins, dietary milk proteins, and intestinal barrier regulation

• Published in: Nutrition reviews 2013-01, Vol.71 (1), p.60-65
• Main Authors: Kotler, Belinda M, Kerstetter, Jane E, Insogna, Karl L
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; claudin; Claudins - genetics; Claudins - metabolism; Diet; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Humans; intestinal barrier function; Intestinal Mucosa - physiology; Milk; Milk Proteins - metabolism; Nutrition; Permeability; Proteins; Smad4 Protein - metabolism; Small intestine; TGFβ; tight junction; Transforming Growth Factor beta - metabolism; Up-Regulation; Vertebrates: anatomy and physiology, studies on body, several organs or systems; whey protein; Whey Proteins
• ISSN: 0029-6643; 1753-4887
• DOI: 10.1111/j.1753-4887.2012.00549.x

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.