Retinal Neurodegeneration in the Course of Diabetes-Pathogenesis and Clinical Perspective

Diabetic retinopathy is generally considered as a microvascular disease which develops as a result of chronic hyperglycaemia. However, the neuronal apoptosis and reactive gliosis are recently postulated as early changes in diabetic retinopathy. This phenomenon is described as a neurodegeneration and suggests that diabetic retinopathy should be recognized as a neurovascular complication. In this review, we discuss the mechanisms leading to the neurodegeneration of the retina in diabetic patients including: low-grade inflammatory process, oxidative stress, activation of polymorphonuclear neutrophils, glutamate excitotoxicity and imbalance in the neuroprotective factors. Secondly, we point out the clinical significance of measuring the retinal neurodegeneration.