Diabetic retinopathy (DR) is a leading cause of blindness. It has long been regarded as vascular disease, but work in the past years has shown abnormalities also in the neural retina. Unfortunately, research on the vascular and neural abnormalities have remained largely separate, instead of being integrated into a comprehensive view of DR that includes both the neural and vascular components. Recent evidence suggests that the most predominant neural cell in the retina (photoreceptors) and the adjacent retinal pigment epithelium (RPE) play an important role in the development of vascular lesions characteristic of DR. This review summarizes evidence that the outer retina is altered in diabetes, and that photoreceptors and RPE contribute to retinal vascular alterations in the early stages of the retinopathy. The possible molecular mechanisms by which cells of the outer retina might contribute to retinal vascular damage in diabetes also are discussed. Diabetes-induced alterations in the outer retina represent a novel therapeutic target to inhibit DR.

糖尿病视网膜病变（DR）是导致失明的主要原因。长期以来，它一直被认为是血管疾病，但过去几年的研究表明神经视网膜也存在异常。不幸的是，对血管和神经异常的研究在很大程度上仍然是分开的，而不是被整合到包括神经和血管成分的 DR 综合视图中。最近的证据表明，视网膜中最主要的神经细胞（感光细胞）和邻近的视网膜色素上皮（RPE）在 DR 特征性血管病变的发展中发挥着重要作用。这篇综述总结了糖尿病中外视网膜发生改变的证据，以及光感受器和 RPE 导致视网膜病变早期阶段视网膜血管改变的证据。还讨论了外视网膜细胞可能导致糖尿病视网膜血管损伤的可能分子机制。糖尿病引起的外视网膜变化代表了抑制 DR 的新治疗靶点。