Changes in the endothelial functional state on the background of diabetic retinopathy (experimental modelling)

Background. Diabetes mellitus remains one of the most widespread diseases among working-age individuals. The insufficient investigation of pathogenetic triggers in the development of this condition leads to the rapid progression of vascular complications, particularly diabetic retinopathy. Objective: to study the functional state of the endothelium under conditions of experimental diabetic retinopathy in rats. Materials and methods. A streptozotocin-induced model of type 2 diabetes mellitus was used. The study was conducted on days 60 and 120, taking into account the levels of endothelin-1, von Willebrand factor, tissue plasminogen activator (t-PA) antigen, intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule (VCAM). Results. There was a significant increase in the levels of endothelin-1, von Willebrand factor, VCAM, accompanied by a decrease in t-PA levels. A local increase in ICAM-1 expression was also observed. These changes, evident as early as day 60 of the experiment, were triggered by marked endothelial cell alteration due to endothelial wall dysfunction. Endothelial dysfunction, in turn, leads to the imbalance of biologically active substances responsible for intercellular interac­tion, vascular function, and the state of the hemostatic system. Conclusions. Changes in the functional state of the endothelial wall represent an important prognostic and pathogenetic link in the development of microvascular diabetic complications, particularly diabetic retinopathy. The study provides valuable insights into the pathogenesis of microvascular diabetic complications and potential therapeutic approaches.