1. Induced Trf2 deletion leads to aging vascular phenotype in mice associated with arterial telomere uncapping, senescence signaling, and oxidative stress
- Author
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R. Garrett Morgan, Lisa A. Lesniewski, Tam T. T. Phuong, Yu Liu, Daniel R. Machin, Kelly D. Reihl, Russell S. Richardson, Grant D. Henson, Daniel W. Trott, Eros Lazzerini Denchi, Samuel I. Bloom, Richard M. Cawthon, Anthony J. Donato, and Ashley E. Walker
- Subjects
Cyclin-Dependent Kinase Inhibitor p21 ,0301 basic medicine ,Senescence ,Aging ,medicine.medical_specialty ,Blood Pressure ,Vasodilation ,030204 cardiovascular system & hematology ,Glycocalyx ,medicine.disease_cause ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Telomeric Repeat Binding Protein 2 ,Molecular Biology ,Cellular Senescence ,Uncapping ,business.industry ,Body Weight ,Telomere Homeostasis ,Arteries ,Telomere ,Phenotype ,Perfusion ,Oxidative Stress ,030104 developmental biology ,medicine.anatomical_structure ,Blood pressure ,Endocrinology ,Adipose Tissue ,Microvessels ,Cardiology and Cardiovascular Medicine ,business ,Gene Deletion ,Oxidative stress ,Signal Transduction ,Artery - Abstract
Age-related vascular dysfunction in large elastic and resistance arteries is associated with reductions in microvascular perfusion and elevations in blood pressure. Recent evidence indicates that telomere uncapping-induced senescence in vascular cells may be an important source of oxidative stress and vascular dysfunction in aging, but the causal relationship between these processes has yet to be elucidated. To test this important unexplored hypothesis, we measured arterial senescence signaling and oxidative stress, carotid and mesenteric artery endothelium-dependent vasodilatory capacity, markers of mesenteric microvascular perfusion and endothelial glycocalyx deterioration, and blood pressure in a novel mouse model of Cre-inducible whole body Trf2 deletion and telomere uncapping. Trf2 deletion led to a 320% increase in arterial senescence signaling (P < 0.05). There was a concurrent 29% and 22% reduction in peak endothelium-dependent vasodilation in carotid and mesenteric arteries, respectively, as well as a 63% reduction in mesenteric microvascular endothelial glycocalyx thickness (all P ≤ 0.01). Mesenteric microvascular perfusion was reduced by 8% and systolic blood pressure was increased by 9% following Trf2 deletion (both P < 0.05). Trf2 deletion also led to a pro-oxidative arterial phenotype characterized by increased in NADPH oxidase gene expression; a 210% increase in superoxide levels that was partly dependent on NADPH oxidase activity; and an oxidative stress-mediated reduction in carotid artery vasodilation (all P ≤ 0.05). Collectively, our findings demonstrate that induced Trf2 deletion leads to telomere uncapping, increased senescence signaling, and oxidative-stress mediated functional impairments in the vasculature similar to those seen in human aging.
- Published
- 2019