The role of Raf-1 kinase in diabetic retinopathy

Expert Opin Ther Targets. 2011 Apr;15(4):357-64. doi: 10.1517/14728222.2011.553604. Epub 2011 Jan 23.

Abstract

Many metabolic pathways, including oxidative stress, PKC and the polyol pathway have been implicated in the development of diabetic retinopathy, but despite extensive research, its pathogenesis remains unclear. Recent studies have shown the role of a low-molecular-weight GTP-binding protein (H-Ras)-mediated signaling pathway in its development. The key effector protein of Ras function is a threonine/serine kinase-Raf kinase, and this kinase is involved in a variety of functions, including the cell cycle and proliferation and apoptosis. In animal models of diabetic retinopathy, Raf kinase is activated in the retina and its microvasculature. Activated Raf kinase is associated with increased apoptosis of retinal capillary cells, the process that precedes the development of retinal histopathology, and inhibition of Raf kinase ameliorates apoptosis. In clinical settings, inhibitors of Raf kinase have shown promising results in cancer treatment, and Raf kinase antisense oligonucleotides, iCo 007, is now in Phase II trial for macular edema, a chronic ocular disease associated with retinal neovascularization. Further elucidating the role of Raf kinase in diabetic retinopathy, and advances in the generation of antisense therapy for chronic diseases, should help test Raf antisense oligonucleotides for the treatment of this blinding complication that diabetic patients fear the most.

Publication types

  • Editorial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Diabetic Retinopathy / drug therapy*
  • Diabetic Retinopathy / enzymology
  • Diabetic Retinopathy / pathology
  • Diabetic Retinopathy / physiopathology
  • Enzyme Inhibitors / therapeutic use
  • Eye / physiopathology
  • Humans
  • MAP Kinase Signaling System
  • Molecular Targeted Therapy
  • Proto-Oncogene Proteins c-raf / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-raf / genetics
  • Proto-Oncogene Proteins c-raf / metabolism*
  • Retina / enzymology
  • Retinal Vessels / enzymology
  • Signal Transduction

Substances

  • Enzyme Inhibitors
  • Proto-Oncogene Proteins c-raf