| Start Date: | 10/21/2021 | Start Time: | 1:00 PM |
| End Date: | 10/21/2021 | End Time: | 3:00 PM |
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Event Description
BIOMED PhD Research Proposal
Title:
Mechanism of Cholesterol Induced Impairment of Capacitative Calcium Entry in Endothelial Cells
Speaker:
Kelly Zaccheo, PhD Candidate
School of Biomedical Engineering, Science and Health Systems
Drexel University
Advisor:
Kenneth Barbee, PhD
Professor
Senior Associate Dean and Associate Dean for Research
School of Biomedical Engineering, Science and Health Systems
Drexel University
Details:
Nitric oxide is a potent vasodilator generated by endothelial nitric oxide synthase (eNOS) in endothelial cells (EC). Early stages of atherosclerosis are marked by endothelial dysfunction–either impaired NO production or bioavailability. Studies have shown that cellular plasma membrane cholesterol levels are elevated in rabbits fed a high cholesterol diet to induce the development of atherosclerotic plaques. Cholesterol is a major component of EC plasma membranes and favors environments with sphingolipids and phospholipids with longer chains. Areas with higher concentrations of cholesterol are considered a liquid ordered (Lo) phase while areas with lower concentrations of cholesterol are liquid disordered (Ld). Changes in cellular cholesterol levels can impact signaling mechanisms by disrupting the integrity of the membrane and spacial organization of signal molecules, leading to the impairment of ion channels or dynamics of membrane proteins in addition to affecting specific interactions between cholesterol and protein channels. Our lab has shown that cholesterol enrichment of bovine aortic endothelial cells (BAECs) impairs capacitive calcium entry (CCE) during agonist stimulated NO production.
To determine the mechanism of impairment, we must be able to separate the effects of cholesterol on membrane properties from direct cholesterol-protein interactions. This project will utilize the properties of the fluorescent dye Laurdan along with novel data analysis techniques termed phasor analysis to examine the effects of cholesterol manipulations, membrane fluidizers and a cholesterol analog on membrane properties and cholesterol content in bovine aortic endothelial cells (BAECs).
Furthermore, we will examine the effects of reagents on agonist stimulated calcium (Ca2+ ) signaling and eNOS phosphorylation. Our goal is to be able to manipulate and characterize changes in membrane fluidity and cholesterol content along with investigating the mechanism by which cholesterol enrichment of BAECs leads to CCE impairment. Insight into the development of the early stages of atherosclerosis can aid in understanding the progression of the disease and help determine possible therapeutic targets. |
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Audience:
Undergraduate StudentsGraduate StudentsFacultyStaff |
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