Advances in diabetic retinal neurodegeneration

Diabetic retinopathy (DR) has long been recognized as a primary microvasculopathy disease.However, more and more studies have proved that diabetic retinal neurodegeneration (DRN) occurs in the early stage of DR, and may precede microvascular disease.Nevertheless, the association between vasculopathy and neuropathy remains unclear.Reduced contrast sensitivity, localized deficits in visual field, electrophysiological changes and thinning of retinal thickness on optical coherence tomography can occur in the early stage of DRN, the main pathological changes for those abnormalities are increased apoptosis of ganglion cells and increased reactivity of glial cells.The imbalance between pro-apoptotic molecules (such as glutamate, angiotensin Ⅱ, etc.) and neuroprotective molecules (such as pigment epithelium-derived factor, somatostatin, etc.), inflammation, and oxidative stress in retinal neurons are important causes of DRN.Strategies for treating neurodegeneration include reducing the production of anti-apoptotic molecules, inhibiting the apoptosis pathway of nerve cells, and using antioxidants and neuroprotective factors.Studies on neurodegeneration have found that early intervention can effectively control the progression of neurodegeneration and prevent the progression of DR in animal models, but there are currently few drugs available for clinical trials.Further research is needed to discover the link between vascular dysfunction and DRN and to evaluate neuroprotective agents for retinal neurodegeneration to develop effective strategies for preventing DR and delaying its progression.This article reviews the clinical detection methods, pathological mechanisms, and intervention strategies of DRN.