Differential Responsiveness of Early and Late Passage Endothelial Cells to Shear Stress

by Juran, Peter

I hypothesize that shear stress helps maintain the quiescent phenotype of vascular endothelium. I also hypothesize that changes in levels of shear stress facilitate alternations in endothelial cell activity consistent with an activated phenotype and the development of atherosclerotic vascular disease. Purpose #1: To assess the effects of aging on EC proliferation induced by SS Hypothesis: Orbital SS stimulates EC proliferation. Aged cells are less responsive to orbital SS and show less proliferation. Purpose #2: To assess the effects of aging on EC survival and apoptosis Hypothesis: Versus younger cells, aged cells have increased rates of apoptosis. Purpose #3: To assess the effects of aging on SS induced SMC chemotaxis Hypothesis: Aged EC are less responsive to orbital SS and induce less SMC chemotaxis versus younger cells. Purpose #4: To assess the effects of aging on Akt pathway activation with SS Hypothesis: Orbital SS activates EC leading to phosphorylation of Akt. Versus younger cells, aged cells are less responsive to orbital SS and show less stress induced phosphorylation of Akt.