Investigation of the molecular mechanisms of vascular endothelial dysfunction in Hutchinson-Gilford Progeria Syndrome through in vitro 2D and 3D models

Abstract Hutchinson-Gilford progeria syndrome (HGPS) is a rare, genetic disorder with features of accelerated aging. The majority of HGPS cases caused by a de novo point mutation in the LMNA gene (c.1824C > T; p.G608G) that results in progerin, a toxic lamin A protein variant. Children with the disease mostly die from coronary artery diseases or strokes at an average age of 14.6

years. Endothelial dysfunction is a key contributor to the cardiovascular pathobiology as the endothelium maintains vascular homeostasis and vascular tone by activating eNOS responsible for nitric oxide (NO) production. Perturbation of eNOS activity causes many diseases including atherosclerosis. Despite the vast knowledge of endothelial dysfunction in the pathogenesis of

cardiovascular disease, very little known about the role of progerin in the disruption of endothelial cell function in HGPS. Furthermore, there is accumulated evidence about the role of progerin in many aspects of generalized aging and cardiovascular health. Particularly, the atherosclerotic plaques in HGPS are similar to those found in aging individuals. Moreover, vascular stiffening in

HGPS is much like that seen on normal aging that manifested in both populations by increased pulse wave velocity. Using human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs), I demonstrated the reduction of endothelial nitric oxide synthase (eNOS) expression level and activity in HGPS

ECs compared to their normal controls. Consequently, the depletion of nitric oxide bioavailability in HGPS ECs both in static and fluidic culture conditions. Remarkably, iPSC-derived HGPS ECs exhibited eNOS dependent functional defects in forming microvascular networks that validated through over-expression of progerin in healthy human umbilical vein endothelial cells (HUVECs).

I also found that Adenine Base Editor (ABEmax) that mediates the conversion of A×T to G×C in genomic DNA efficiently corrected the HGPS mutation, and the progerin expression was significantly reduced to the basal level. In addition, ABEmax rescued the nuclear blebbing phenotype of the HGPS iPSC-ECs. Thus, the study provides valuable insights into HGPS

cardiovascular pathology and cardiovascular diseases associated with normal aging, and may lead to novel strategies to treat cardiovascular disease in HGPS.