Metabolic Stress-Induced Choline Kinase α (CHKA) Activation in Endothelial Subpopulation Contributes to...

Diabetes is a prevalent metabolic disorder, and its associated microvascular dysfunction plays a key role in the pathogenesis of complications such as retinopathy, nephropathy, and peripheral vascular disease. However, the mechanism governing metabolic regulation and functional heterogeneity of endothelial dysfunction remains incompletely understood. This study investigates the role of metabolic stress-induced activation of choline kinase α (CHKA) in endothelial cell (EC) subpopulations, contributing to diabetes-induced microvascular dysfunction. Using single-cell RNA sequencing (scRNA-seq), three distinct EC subclusters are identified within retinal vessels. Among them, one subcluster characterized by elevated CHKA expression is associated with enhanced angiogenic activity. CHKA silencing in ECs inhibited angiogenic effects and reduced retinal vascular dysfunction in diabetic murine models. CHKA silencing also disrupted NAD⁺ metabolism, causing reduced NAD⁺ levels. Supplementation with nicotinamide mononucleotide (NMN), a precursor of NAD⁺, partially reversed the anti-angiogenic effects induced by CHKA silencing. Mechanistically, CHKA regulated endothelial dysfunction through the NAD⁺-SIRT1-Notch signaling. Clinical sample analysis and Mendelian randomization studies provided strong evidence linking increased CHKA expression with diabetic microvascular complications. Collectively, this study advances the understanding of endothelial heterogeneity and identifies CHKA as a critical regulator of pathological angiogenesis, highlighting its potential as a therapeutic target for diabetic vascular complications.