Vascular Mimetics to Study Inflammation and Atherosclerosis

University Of California At Davis, Davis CA

Investigators

Linked publications & trials

Abstract

DESCRIPTION (provided by applicant): This competitive renewal is focused on atherosclerosis, the primary cause of mortality in Western society. Our studies and others reveal that arterial plaque formation closely correlates with visceral obesity and concomitant high levels of circulating triglyceride rich lipoproteins (TGRL), especially associated with diets high in saturated fat. Over the tenure of this grant, we have developed an ex-vivo model of early inflammatory events of atherogenesis by studying blood monocytes and TGRL isolated postprandial from plasma of subjects ranging from healthy to obese and hypertriglyceridemic. By examining their interaction with low passage cultured human aortic endothelial cells (HAEC), we have reported that acute exposure to TGRL augmented cytokine- induced VCAM-1 expression and monocyte recruitment under shear stress. In subjects exhibiting high cardiovascular risk (i.e. high postprandial TGRL and abdominal obesity) we detected increased foamy monocytes in blood and correlated this with integrin activation and arrest to VCAM-1, as quantified in our vascular mimetic shear flow assay. These data provide a framework for quantifying an individual's atherogenic susceptibility. Our primary hypothesis is that we can delineate the metabolic pathways that go awry and correlate these with biomarkers of endothelial and monocyte inflammation measured ex vivo in order to provide valuable clinical insight in assessing an individual's risk for developing inflammation-mediated coronary artery disease. A systems bioengineering approach is applied to study metabolic and biomechanical responses at the cell and molecular scale using real time imaging and novel microfluidic technology in three specific aims: 1) Quantify an individual's metabolic profile following a high-fat meal in terms of the inflammatory capacity of their TGRL. 2) Delineate how TGRL signaling pathways regulate an atherogenic profile in aortic endothelium. 3) Identify the earliest events linked to hypertriglyceridemia and obesity that increase monocyte proclivity to arrest on atherogenic endothelium using a lab-on-a-chip assay. Our overall goal is to develop assays that pinpoint the extent to which dietary lipoproteins from healthy and metabolic syndrome subjects are exerting pro- inflammatory effects that shift the balance from healthy to atherogenic vasculature.