Abstract Th0074: Single-cell Transcriptome Profiling of the Aorto-Iliac Region in Diabetic Peripheral Arterial Disease

Introduction: The prevalence of peripheral arterial disease (PAD) has significantly risen, especially among individuals with diabetes, though the pathophysiological mechanisms underlying diabetic vasculopathy remain incompletely defined. A crucial element of diabetic angiopathy is the interplay between endothelial cells (ECs) and Inflammatory cells within the vascular microenvironment. We propose that hyperglycemia-induced activation of ECs potentiates monocyte recruitment and subsequent differentiation into macrophages, exacerbating vascular inflammation and complications in diabetic PAD. Identifying this process's cellular and molecular drivers could uncover therapeutic targets to mitigate disease progression. Methods: We employed db/db mice, a widely recognized model of type 2 diabetes, alongside sibling-matched wild-type controls to elucidate gene expression dynamics in the aortoiliac region. Using single-cell RNA sequencing, we dissected cellular populations and evaluated transcriptional changes in ECs and immune cells. This approach enabled the identification of differential gene expression profiles and functional pathway enrichment, offering insights into cell-type-specific responses associated with diabetic vascular pathology. Results: Our analysis revealed ten discrete cell populations, including stromal cells, ECs, vascular smooth muscle cells (SMCs), and diverse immune cell types. We identified ECs and SMCs cell types in the aortoiliac region by immunofluorescence and compared the representative markers (CD31 for ECs and SMA for SMCs) and found no significant differences in expression levels between wild-type and db/db. Top 5 genes found in the subpopulations of ECs and SMCs and compared the correlations of expressed genes through biological function analysis. In this comparison, db/db aortic-iliac endothelium showed significant upregulation of Notch3, which is associated with Angiopoietin-2, and upregulation of KIK10, which plays a role in inducing permeability dysfunction and inflammation by association with VCAM1. In SMCs, we identified Pde4 and Vcam1, which play a role in promoting cell proliferation and adhesion, as key regulators upregulated in db/db. Conclusions: This study elucidates differential gene expression patterns in ECs and SMCs within the aortoiliac region of db/db mice, highlighting specific genes as potential biomarkers and therapeutic targets for diabetic vasculopathy.