Intestinal barrier tight junction and desmosomal protein complexes (TJ/Desmosome complexes)

The intestinal barrier tight junction and desmosomal protein complexes are specialized intercellular structures essential for maintaining the selective permeability and mechanical integrity of the intestinal epithelium (PMID: 30126151). Tight junctions (TJs) form a continuous seal between adjacent epithelial cells, composed of transmembrane proteins such as claudins, occludin, and junctional adhesion molecules (JAMs), which are linked to the actin cytoskeleton via zonula occludens (ZO) proteins (PMID: 28117447). Desmosomes, located basal to TJs, provide robust mechanical adhesion by tethering the intermediate filament network through desmogleins and desmocollins (PMID: 25231868). Disruption of these complexes increases paracellular permeability, often referred to as leaky gut, which is a hallmark of diseases like Celiac disease, Inflammatory Bowel Disease (IBD), and Irritable Bowel Syndrome (IBS) (PMC4253991). Therapeutic strategies targeting these complexes, such as the zonulin antagonist larazotide acetate, aim to restore barrier function by preventing junctional disassembly (PMID: 26075913). Understanding the regulation of these protein complexes is vital for developing treatments that mitigate systemic inflammation and autoimmune triggers originating from the gut.

Other names

Apical junctional complex (AJC)Intestinal epithelial junctional complexesParacellular barrier proteinsIntestinal mucosal barrier junctions

Zonulin antagonism to prevent tight junction disassembly, upregulation of claudin expression to enhance barrier tightness, and stabilization of the apical junctional complex through cytoskeletal anchoring.