OSSC1E-K19, a novel phytochemical component of Osteomeles schwerinae, prevents glycated albumin-induced retinal vascular injury in rats

In the pathophysiology of diabetic retinopathy (DR), advanced glycation end products (AGEs) and vascular endothelial growth factor (VEGF) are thought to have impor- tant roles. It is known that VEGF causes a breakdown of the blood-retinal barrier (BRB) and retinal neovascularization; however, how AGEs affect the retina has largely remained elusive. OSSC1E-K19 is a novel phytochemical component of Osteomeles schwerinae. The objective of the present study was to evaluate the protective effects of OSSC1E-K19 on retinal vascular injury in AGE-modified rat serum albumin (AGE-RSA)-induced retinopathy. AGE-RSA-injected rat eyes were used investigate the protective effects of OSSC1E-K19 on BRB breakdown. Intravitreal injection of OSSC1E-K19 prevented AGE-RSA-induced BRB breakdown and decreased retinal VEGF expression in retinal vessels. In addition, OSSC1E‑K19 inhibited the loss of occludin, a significant tight junction protein. These results supported the potential thera- peutic utility of OSSC1E-K19 for retinal vascular permeability diseases.