Pathogenesis Study Based on High-Throughput Single-Cell Sequencing Analysis Reveals Novel Transcriptional Landscape and Heterogeneity of Retinal Cells in Type 2 Diabetic Mice

Diabetic retinopathy (DR) is the leading cause of acquired blindness in middle-aged people. The complex pathology of DR is difficult to dissect, given the convoluted cytoarchitecture of the retina. Here, we performed single-cell RNA sequencing (scRNA-seq) of retina from a model of type 2 diabetes, induced in leptin receptor-deficient (db/db) and control db/m mice, with the aim of elucidating the factors mediating the pathogenesis of DR. We identified 11 cell types and determined cell-type-specific expression of DR-associated loci via genome-wide association study (GWAS)-based enrichment analysis. DR also impacted cell-type-specific genes and altered cell-cell communication. Based on the scRNA-seq results, retinaldehyde-binding protein 1 (RLBP1) was investigated as a promising therapeutic target for DR. Retinal RLBP1 expression was decreased in diabetes, and its overexpression in Müller glia mitigated DR-associated neurovascular degeneration. These data provide a detailed analysis of the retina under diabetic and normal conditions, revealing new insights into pathogenic factors that may be targeted to treat DR and related dysfunctions.