Single cell transcriptomic analysis identifies novel vascular smooth muscle subsets under high hydrostatic pressure

Although some co-risk factors and hemodynamic alterations are involved in hypertension progression, their direct biomechanical effects are unclear. Here, we constructed a high-hydrostatic-pressure cell-culture system to imitate constant hypertension and identified novel molecular classifications of human aortic smooth muscle cells (HASMCs) by single-cell transcriptome analysis. Under 100-mmHg (analogous to healthy human blood pressure) or 200-mmHg (analogous to hypertension) hydrostatic pressure for 48 h, HASMCs showed six distinct vascular SMC (VSMC) clusters according to differential gene expression and gene ontology enrichment analysis. Especially, two novel HASMC subsets were identified, named the inflammatory subset, with CXCL2, CXCL3 and CCL2 as markers, and the endothelial-function inhibitory subset, with AKR1C2, AKR1C3, SERPINF1 as markers. The inflammatory subset promoted CXCL2&3 and CCL2 chemokine expression and secretion, triggering monocyte migration; the endothelial-function inhibitory subset secreted SERPINF1 and accelerated prostaglandin F2α generation to inhibit angiogenesis. The expression of the two VSMC subsets was greatly increased in arterial media from patients with hypertension and experimental animal models of hypertension. Collectively, we identified high hydrostatic pressure directly driving VSMCs into two new subsets, promoting or exacerbating endothelial dysfunction, thereby contributing to the pathogenesis of cardiovascular diseases.