CNS targets for the treatment of retinal dystrophies: a Win-Win strategy

Abstract

As an extension of the central nervous system (CNS), the retina shares with the brain certain developmental, physiological, and pathological characteristics. However, the underlying mechanisms and pathological signs common to neurodegenerative conditions of both the retina and brain have been relatively overlooked. In animal models and in human patients, marked retinal alterations have been demonstrated in Alzheimer´s disease,Parkinson´s disease, and multiple sclerosis, among other pathologies. Furthermore,neurodegeneration of the retina and brain appears to be mediated by similar mechanisms,which include protein aggregation, neuroinflammation, and cell death. Analysis of the retina, which is easily accessible to objective techniques, may therefore constitute an effective tool for the screening and follow-up of CNS neurodegeneration. Moreover,patients with retinal neurodegeneration could potentially benefit from the broad array of pharmacological compounds that have been designed and tested for the treatment of the aforementioned CNS pathologies. Supporting this view, we have shown that GSK-3 inhibitors, which have already been tested in clinical trials to treat several neurodegenerative conditions of the brain, attenuate retinal damage and vision loss in a mouse model of retinitis pigmentosa. Furthermore, systemic proinsulin treatment preserves visual and cognitive function in mouse models of retinitis pigmentosa and precocious aging, respectively.