Authors: G. Colton Gardner, Lynasi Gapelu, Sohom Mookherjee, Sihem Boudina, J. David Symons
Mentors: J. David Symons
Insitution: University of Utah
With the prevalence of cardiovascular disease increasing world wide and its precise mechanisms remaining elusive, the need for novel treatments is urgent. Autophagy is a conserved process whereby dysregulated intracellular proteins are escorted to the lysosome for recycling. Emerging evidence indicates that autophagy is important in maintaining endothelial cell (EC) proteostasis and function. My laboratory showed that autophagy repression in adult mice ECs produces arterial dysfunction, and indexes of autophagy are repressed in ECs of older mice and humans which display concurrent EC dysfunction. Sequestosome 1 (p62) tethers proteins and enables their entry into the autophagic pathway. The contribution from EC p62 to cardiovascular and metabolic function is unknown and experiments are needed to investigate this. Thus, p62 will be depleted from ECs of adult male and female mice (p62iEC-/-) via tamoxifen regimen, and results will be compared to animals wherein EC p62 is intact (CON). The efficacy and specificity of EC p62 depletion will be evaluated in ECs and vascular smooth muscle by qPCR and immunoblotting. Three adjacent 1 mm thoracic aorta sections will be obtained 14 days after the tamoxifen regimen. The central aorta section will be used to measure intrinsic mechanical stiffness by wire myography, with the other two used to find lumen diameter and intimal medial thickness. These measurements will help create Stress vs. Strain curves and the Elastic Modulus, which will be compared between the groups to show the differences caused by p62 depletion. We expect p62 depletion from ECs to increase intrinsic aortic stiffness.