Researchers from the Diabetes and Metabolism group at Vall d'Hebron Institute of Research (VHIR) have discovered that the topical administration of one of the current treatments for diabetes type 2 may prevent diabetic retinopathy. The treatment is composed of the GLP-1 hormone receptor agonists, which are usually administered subcutaneously, in order to help the pancreas to produce more insulin. The study has been published in http://diabetes.diabetesjournals.org/content/early/2015/09/15/db15-0443.abstract?sid=e7eaccfe-2226-4230-9e9a-08964c6e8f32" Diabetes.Before any microcirculatory abnormalities can be detected under ophthalmoscopic examination, retinal neurodegeneration is already present, and the process is asymptomatic. With the aim to prevent and/or treat this retinal neurodegeneration, VHIR researchers selected GLP-1 receptor agonists as a therapeutic target, because they were already known for their neuroprotective effects in the central nervous system. This receptor had been previously detected in the retina of animals, but its expression in human retina had never been analyzed."We have identified, for the first time, the presence of GLP-1 receptors in human retina and that patients with diabetes have lower expression of these receptors", says Dr. Rafael Simó, principal investigator of the study. He adds that "this discovery allows us to propose a replacement therapy with a natural agent that it is produced in the human retina, but it is underexpressed in diabetes patients". A total of 8 donors with diabetes and eight donors without the disease were included in the study.Their next step was to assess in a murine model of diabetes the effects of GLP-1 in the neurodegeneration process, administered by both ways: by topical administration, using eyedrops, and by subcutaneous administration, as it is already administered in many patients with diabetes type 2. As a result, they found a similar neuroprotective effect in both administrations.Dr. Simó remarks that "the neuroprotective action was observed without any reduction in blood glucose levels, so this treatment can be also administered using eye drops". Thus, the treatment can be used in patients who don't need to increase the insulin, such as diabetes type 1 patients, and in those patients that can't receive the subcutaneous GLP-1 treatment because of the side effects.Researchers have now started preclinical studies with the aim to set up a clinical trial with patients. Their goal is to demonstrate the added benefits of these treatments, that have already been in the market for years and, then, there are no doubts about their security. EUROCONDOR projectDr. Rafael Simó's group has wide experience in the study of diabetic retinopathy. He is currently leading the European consortium EUROCONDOR, funded by the 7th Framework Programme of the European Commission, under the number 278040, with the aim to find an early treatment for the diasease.Last October they finished the clinical trial of this project in which have participated 450 patients from Europe. They tested the effects of a non-invasive (eye drops) and innovative treatment (somatostatin) specifically targeting the earliest stages of the disease. The results are expected and will be made public by March of 2016.