Use of long-acting somatostatin analogue treatment in diabetic retinopathy

The diabetes epidemic continues unabated, leading to an increasing number of acute and chronic complications, including sight-threatening proliferative diabetic retinopathy. Currently, there is no accepted pharmaceutical therapy for diabetic retinopathy besides nearnormal glycemia, treatment of hypertension, and dyslipidemia. For an effective treatment of retinopathy, one would recommend a concept leading to the downregulation of endogenous angiogenic stimulators and the upregulation of endogenous angiogenic inhibitors, resulting in a restoration of the balance in angiogenic control. The naturally occurring growth hormone inhibitor, somatostatin, has been suggested as candidate for developing novel therapies. Somatostatin may exert its antiangiogenic effects, both through antagonism of the growth hormone axis and through direct antiproliferative and apoptotic effects on endothelial cells. Therefore, the use of long-acting somatostatin analogues will lead to an upregulation of antiangiogenic signaling. Use of long-acting somatostatin analogues in diabetic retinopathy would be an important extension of the initial concept that somatostatin is a regulator of growth hormone secretion only. Currently available analogues have already allowed to modulate the expression of diabetic retinopathy at various disease stages. Somatostatin analogues remain the only nondestructive therapeutic alternative to patients with proliferative diabetic retinopathy who have failed to respond to panretinal photocoagulation.