Retinal Cell Loss Associated with Alzheimer’s Disease

Vision deterioration is a symptom of Alzheimer’s Disease (AD). Neural cells that make up the visual pathway from the retina to the brain degenerate in AD. However, the identity of the neural cells underlying this loss of vision is still unknown. The ability to identify the visual cells that degenerate in AD could facilitate the diagnosis of the disease and the tracking of its progression. An international team of researchers investigating this phenomenon has recently reported that a particular layer of retinal cells, the inner nuclear layer, could provide this step in clinical advancement.

Researchers from Georgetown University Medical Centre and the University of Hong Kong investigated the link between vision loss and AD using a mouse model that was genetically engineered to exhibit AD pathology. On examining retinas from the eyes of these mice, the group noticed that inner nuclear layer cells, which had not previously been studied, had degenerated compared to those of healthy age-matched control mice.

The majority of research in the field to date has focused on the degeneration of the retinal ganglion layer cells, to the neglect of the inner nuclear layer cells. There was a significant loss of thickness of both cell layers in the mice with AD pathology in this study, indicating substantial cell degeneration. It was therefore proposed that the state of inner nuclear layer cells could provide a possible predictive measure of AD onset and progression in humans.

The thickness and structure of retinal cell layers in humans is easily measurable by optical coherence tomography. If inner nuclear layer cells degeneration proves to be a marker of AD in humans, it could provide novel means of measuring the progression of the disease in everyday clinical practice. Furthermore, drugs used to treat AD could be administered to patients with glaucoma, with the aim of minimizing retinal cell loss.

Read more at: http://explore.georgetown.edu/news/?ID=73188&PageTemplateID=295