Tight junction integrity

Tight junction integrity refers to the structural and functional stability of the zonula occludens, a specialized cell-cell adhesion complex that seals the paracellular space between epithelial or endothelial cells (StatPearls, 2023). These junctions are composed of transmembrane proteins, including claudins, occludin, and junctional adhesion molecules (JAMs), which interact with intracellular scaffold proteins like zonula occludens-1 (ZO-1) to link the barrier to the actin cytoskeleton (PubMed, 2021). The primary biological function of tight junction integrity is to maintain a selective permeable barrier, regulating the transport of ions and solutes while preventing the entry of pathogens and toxins into the systemic circulation (NIH, 2022). Loss of integrity is a hallmark of various pathologies, including inflammatory bowel disease, celiac disease, and blood-brain barrier breakdown in neurodegenerative disorders (PubMed, 2020). Pharmacological intervention typically focuses on stabilizing these complexes or inhibiting signaling molecules like zonulin that trigger junction disassembly (PubChem, 2023). For example, larazotide acetate is a peptide that acts as a zonulin antagonist to reduce intestinal permeability in celiac disease patients (PubMed, 2022). Maintaining this integrity is crucial for tissue homeostasis, as its disruption can lead to chronic inflammation and systemic immune activation (NIH, 2022).

Other names

Epithelial barrier functionParacellular barrierZonula occludens integrityMucosal barrier integrity

Modulation of paracellular permeability through the regulation of transmembrane protein assembly (e.g., claudins, occludin) and the inhibition of zonulin-mediated junction disassembly.