Modulation of tight junction integrity by food components

The primary function of the human intestine is to absorb nutrients and water. However, equally important is its ability to act as a selective barrier to protect the human system. Intestinal epithelium is formed by a monolayer of epithelial cells. Adjacent cells of the monolayer are sealed together by the formation of tight junctions (TJs)–complex protein systems. The structure of TJ involves transmembrane proteins linked to a cytoplasmic plaque, which is formed by a network of scaffolding and adaptor proteins, signalling components and actin-binding cytoskeleton linkers. TJs regulate paracellular transport of compounds as well as physical barrier function of epithelium, which is linked to pathogenesis of inflammatory bowel disease, ulcerative colitis, Crohn's disease and food allergies. Epithelium is intensively exposed to food components. Various food components can affect the functioning of TJ by modifying expression of TJ protein components and affecting signalling pathways involved in TJ regulation. The targeted usage of food components to modulate TJ permeability is of vital importance for enhancing the absorption of poorly permeable drugs or bioactive compounds and, on the other hand, for sealing the junction in order to limit the risk of intestine pathology. The aim of this review is to compile and analyse the previous research investigating the possible relevance of food components to TJ regulation, with a special consideration of phenolic compounds