Hutchinson Gilford Progeria Syndrome alters the endothelial genetic response to laminar shear stress
Hutchinson-Gilford Progeria Syndrome (HGPS) is a fatal, accelerated-aging disease caused by a mutation in the nuclear envelope protein Lamin A. The resulting mutant protein, progerin, accumulates on the nuclear envelope, causing nuclear blebbing, altered gene expression, and other cellular defects. The primary pathology of HGPS is atherosclerosis, leading to stroke or heart attack. Given that atherosclerosis begins with endothelial dysfunction in non-HGPS individuals, we examined whether the HGPS endothelium has an altered genetic response to shear stress, contributing to atherogenesis. We examined morphology and gene expression of HGPS and healthy iPSC-derived endothelial cells (viECs) after exposure to steady laminar shear stress (12 dynes/cm^2 for 24 hours) in a parallel-plate flow channel. We found that elongation in response to flow is impaired in HGPS viECs compared with healthy viECs. Differential expression (DE) analysis showed fewer significant differentially expressed genes and a lower magnitude of gene expression change after flow in HGPS compared with healthy viECs. Gene Set Enrichment Analysis identified differences in the gene sets altered by flow-induced DE, including Cholesterol Homeostasis, which was overrepresented in HGPS viECs. LGALS3, encoding the atherosclerosis marker galectin-3, was a main driver of this overrepresentation. RT-PCR confirmed LGALS3 as a shear-sensitive gene robustly upregulated in HGPS viECs compared with healthy viECs after flow. Treatment with an adenine base editor correcting the HGPS mutation restored LGALS3 expression to healthy levels. These observations indicate that HGPS ECs have an aberrant molecular response to atheroprotective shear stress, contributing to atherogenesis in HGPS patients. Overall design: RNA sequencing of iPSC-derived endothelial cells after 24h shear stress at 12dynes/cm^2 and accompanying static controls. ECs are healthy or diseased (HGPS).