**5. The relationship between occludin and vascular endothelial injury-related diseases**

Vascular endothelial injury includes vasodilation dysfunction characterized by decreased endothelial NO and structural damage characterized by increased endothelial inflammatory response, endothelial cell apoptosis, and endothelial cell permeability. A large number of studies have found that the abnormal expression and modification of occludin is accompanied by damage to the endothelial structure of blood vessels in tissues and organs, resulting in increased vascular permeability, inflammatory cell infiltration, and apoptosis. Therefore, we will detail the relationship between occludin and diseases related to damage to the arterial vascular endothelial structure in this section.
