Bibliogr.

Aims: Dysfunctional endothelium contributes to the initiation and progression of atherosclerosis. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcription factor that regulates the expression of antioxidant and cytoprotective genes. Reduced activity of Nrf2 can contribute to endothelial dysfunction. While the role of endothelial Nrf2 in vascular homeostasis is well supported, several knowledge gaps remain, particularly regarding its cell type-specific contributions and crosstalk mechanisms in vascular disease progression. Materials and methods: Atherosclerosis was induced in mice with transcriptionally inactive Nrf2 in cadherin 5 (Cdh5)-expressing cells () and appropriate control mice via adeno-associated viral vector (AAV)-mediated overexpression of murine proprotein convertase subtilisin/kexin type 9 (Pcsk9) in the liver and high-fat diet feeding. In addition to histological analysis, single-cell RNA sequencing (scRNA-seq) was performed to investigate the cellular composition of healthy and atherosclerotic mouse aortas and examine their gene expression characteristics. Key findings: Loss of Nrf2 transcriptional activity in mice promoted aortic root lesions formation. The scRNA-seq analysis performed on the aortas of mice revealed a specific transcriptomic profile of endothelial cells (ECs) lacking Nrf2 activity, including altered expression of genes regulating shear stress, inflammation, vascular permeability, and secretion of proatherogenic factors. Additionally, cellular crosstalk analysis revealed significant alterations in the atherosclerotic aortas of mice, including weakened communication probability between ECs and (myo)fibroblasts and enhanced interactions between ECs and inflammatory macrophages. Significance: Endothelial Nrf2 deficiency promotes atherosclerosis by inducing inflammatory traits in ECs and shifting vascular cell communication dynamics.