Diabetic Retinopathy and Diabetic Neuropathy

Perspectives on the News commentaries are now part of a new, free monthly CME activity. The Mount Sinai School of Medicine, New York, New York, is designating this activity for 2.0 AMA PRA Category 1 credits. If you wish to participate, review this article and visit www.diabetes.procampus.net to complete a posttest and receive a certificate. The Mount Sinai School of Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This is the sixth in a series of articles on presentations at the American Diabetes Association’s 66th Scientific Sessions, Washington, DC, 9–13 June 2006, reviewing aspects of diabetic retinopathy and neuropathy and lower extremity vascular disease.Maria Grant (Gainesville, FL) discussed the treatment of diabetic retinopathy with insulin-like growth factor (IGF)-1 antagonists, reviewing a number of lines of evidence. There is evidence of hypersecretion of growth hormone in diabetes. Furthermore, diabetic retinopathy has been seen following administration of growth hormone to individuals without diabetes (1); there is evidence of reduction in diabetic retinopathy in growth hormone–deficient individuals (2), and pituitary ablation has been shown to have a benefit in reducing diabetic retinopathy progression (3). A number of studies have addressed the potential benefit of somatostatin and its analogs in the treatment of diabetic retinopathy (4). IGF-1 causes a phosphatidylinositol 3-kinase–mediated increase in vascular endothelial growth factor (VEGF) expression by retinal pigment epithelial cells leading to effects on retinal endothelial cells. Somatostatin reduces circulating IGF-1, as well as acting directly in the retina to reduce VEGF production and to decrease retinal neovascularization, with three of the five somatostatin receptor subtypes having been identified in the retina.Octreotide is an eight–amino acid synthetic peptide acting at somatostatin receptors. In a 15-month study of the effect of administration of octreotide to diabetic individuals with …