Diabetic retinopathy is considered one of the vision-threatening diseases among 
working-age population. The pathogenesis of the disease is regarded 
multifactorial and complex: capillary basement membrane thickening, loss of 
pericytes, microaneuryms, loss of endothelial cells, blood retinal barrier 
breakdown and other anatomic lesions might contribute to macular edema and/or 
neovascularization the two major and sight threatening complications of diabetic 
retinopathy. A number of proangiogenic, angiogenic and antiangiogenic factors 
are involved in the pathogenesis and progression of diabetic retinal disease, 
Vascular Endothelial Growth Factor (VEGF) being one of the most important. Other 
growth factors, which are known to participate in the pathogenesis of the 
disease, are: Platelet Derived Growth Factor (PDGF), Fibroblast Growth Factor 
(FGF), Hepatocyte Growth Factor (HGF), Transforming Growth Factor (TGF), 
Placental Endothelial Cell Growth Factor (PlGF), Connective Tissue Growth Factor 
(CTGF). Other molecules that are involved in the disease mechanisms are: 
intergrins, angiopoietins, protein kinase C (PKC), ephrins, interleukins, 
leptin, angiotensin, monocyte chemotactic protein (MCP), vascular cell adhesion 
molecule (VCAM), tissue plasminogen activator (TPA), and extracellular matrix 
metalloproteinases (ECM-MMPs). However, the intraocular concentration of 
angiogenic factors is counterbalanced by the ocular synthesis of several 
antioangiogenic factors such as pigment epithelial derived factor (PEDF), 
angiostatin, endostatin, thrombospondin, steroids, atrial natriuretic peptide 
(ANP), inteferon, aptamer, monoclonal antibodies, VEGF receptor blocker, VEGF 
gene suppressors, intracellular signal transduction inhibitors, and 
extracellular matrix antagonists. Growth stimulation or inhibition by these 
factors depends on the state of development and differentiation of the target 
tissue. The mechanisms of angiogenesis factor action are very different and most 
factors are multipotential; they stimulate proliferation or differentiation of 
endothelial cells. This review attempts to briefly outline the knowledge about 
peptide growth factor involvement in diabetic retinopathy. Further ongoing 
research may provide better understanding of molecular mechanisms, disease 
pathogenesis and therapeutic interactions.