Despite the better options of controlling diabetes mellitus and although the prognosis of diabetic retinopathy has markedly improved by laser treatment and vitreoretinal surgery, diabetic retinopathy still is the leading cause of blindness in working age people in industrialized countries. Little has changed in the last decades regarding the prognosis of ocular complications in diabetes mellitus. We therefore need better tools and new therapeutic approaches for the prevention and treatment of diabetic ocular complications. Newer therapeutic options are directed at the causative mechanisms of diabetic retinopathy. Experimental and clinical evidence suggests that pharmacological compounds like somatostatin analogues and protein kinase C (PKC) inhibitors may be effective in the treatment of diabetic retinopathy. Chronic overproduction of growth hormone and insulin-like growth factor 1 play an important role in the pathogenesis of diabetic retinopathy. In the treatment of diabetic retinopathy somatostatin receptors are the targets of somatostatin analogues like octreotide. Octreotide has shown to be a promising treatment of diabetic retinopathy and diabetic macular edema. One important pathomechanism in the development of diabetic retinopathy is the activation of PKC induced by high glucose due to an increased diacylglycerol level. The selective PKC-β inhibitor ruboxistaurin mesylate enables a new therapeutical approach for the treatment of diabetic retinopathy. Ongoing prospective clinical trials investigate whether the treatment with the specific PKC-β inhibitor can prevent the progression of diabetic retinopathy and diabetic macular edema.

Keywords:
Diabetic retinopathy, Somatostatin analogue, Octreotide, Protein kinase C inhibitor, Ruboxistaurin mesylate
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© 2007 S. Karger AG, Basel
2007
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