Intestinal and skin epithelial barrier

The intestinal and skin epithelial barriers are complex physiological systems that maintain homeostasis by acting as a selective physical and chemical shield against the external environment (Nature Reviews Gastroenterology & Hepatology, 2014). These barriers are composed of epithelial cells interconnected by specialized protein complexes, including tight junctions, adherens junctions, and desmosomes (Journal of Investigative Dermatology, 2012). In the intestine, the barrier is further reinforced by a mucus layer and antimicrobial peptides, whereas the skin barrier relies on the lipid-rich stratum corneum (PubMed, PMC4616219). Impairment of these barriers leads to increased permeability, allowing the translocation of pathogens and allergens, which triggers chronic inflammation seen in conditions like inflammatory bowel disease (IBD) and atopic dermatitis (NIH, StatPearls). While not a single molecular target, therapeutic strategies aim to restore barrier integrity by modulating signaling pathways, such as the GLP-2 pathway with drugs like Teduglutide, or by neutralizing cytokines like IL-4 and IL-13 with Dupilumab to improve skin barrier function (PubChem).

Other names

Epithelial barrier functionMucosal barrierSkin barrierGut barrierEpidermal barrierIntestinal permeability

Therapeutic agents typically act by upregulating tight junction proteins, inhibiting pro-inflammatory cytokines that compromise barrier integrity, or providing physical/chemical supplementation to the barrier surface.