Role Of Phosphatidylinositol 3-kinase In Proliferation And VEGF Expression In Hypoxic Human RPE Cells

Background Neovascularization is associated with various ocular disorders, often causing severe loss of vision and eventually blindness,Such as,diabetic retinopathy and age-related macular degeneration (AMD).VEGF is up-regulated by hypoxia and is a major stimulatory factor for retinal and choroidal neovascularization. In an animal model, CNV was induced by subretinal injection of VEGF. A transgenic murine model of AMD has been established successfully, in which the overexpression of VEGF by RPE cells induces CNV. All these showed the important role of VEGF in the formation of CNV.Retinal microvascular endothelial cells, pericytes and retinal pigment epithelium cells all can produce VEGF. In particular, RPE cells have the most potential to express VEGF.Hypoxia can activate several signal pathways. Among them, phosphatidylinositol 3-kinase (PI3K) are ubiquitous enzymes involved in signal transduction. Their activity is essential in numerous cellular functions,...