Insights from RNA sequencing techniques revealing the molecular mechanisms associated with diabetic retinopathy

Diabetic retinopathy (DR), a leading cause of vision loss worldwide, is triggered by complex molecular pathways that involve oxidative stress, inflammation, and vascular dysfunction. The introduction of RNA sequencing (RNA-Seq) technology has significantly enhanced our understanding of DR etiology, providing high-resolution insights into gene expression patterns and cellular interactions. This review scrutinizes the application of bulk RNA-Seq and single-cell RNA sequencing (scRNA-Seq) in analyzing the molecular underpinnings of DR, emphasizing critical pathways such as Vascular endothelial growth factor A (VEGF), Interleukin-17 (IL-17), and Phosphatidylinositol 3-kinase (PI3K) - AKT signaling pathways, and revealing possible biomarkers including Bone Morphogenetic Protein 4 (BMP4), SMAD Family Member (SMAD9), and microRNAs. Synthesizing findings from both bulk and single-cell RNA-Seq, this review delineates an emerging paradigm shift in DR research from a vessel-centric to an ecosystem-centric view, uncovering critical cell-specific contributions to disease pathogenesis and highlighting the complementary roles of these technologies in translating discoveries from animal models to human disease. The review also reports that various pharmacological candidates, including curcumin and Transthyretin (TTR), have surfaced from these investigations and show promise in reducing angiogenesis and inflammation. In addition to the aforementioned comparative studies involving animal models, human research, and cell line investigations have revealed species-specific transcriptional patterns and conserved pathways, underscoring the translational significance of RNA-Seq data. These findings provide a foundation for identifying potential therapeutic targets involved in angiogenesis, neurodegeneration, and inflammation, offering new directions for future research in DR management.