Cardiovascular disease (CVD) is driven by complications of inflammation in atherosclerotic plaque. The endothelium is a key component to the progression of this disease, as innate immune cell recruitment to the arterial wall and the subsequent inflammatory response are endothelial cell dependent. The proinflammatory cytokines that are secreted as part of this inflammatory response activate the NFB signaling pathway as well as endothelial cells, causing an upregulation of the cell adhesion molecules Icam1 and Vcam. We performed the first broad analysis of the alternative splicing events in the inflamed arterial endothelium under low and disturbed blood flow (LDF) conditions, mimicking those seen during the progression of CVD, in response to innate immune cell recruitment. Weve shown that some of these changes were required to prevent intimal rupture under disturbed flow conditions and that about 1/3 are innate immune cell dependent. We performed in vitro CRISPR screens to identify top candidates to pursue individually from the pool of regulators for those splicing changes. We identified Ptbp1, an RNA-binding protein that binds to the polypyrimidine tract of introns, as one of those top candidates. Previously published literature on Ptbp1 suggests that Ptbp1 helps to regulate the inflammatory response to senescence. In turn, the progression of senescence parallels the progression of atherosclerosis, suggesting senescense and Ptbp1 play a role in cardiovascular disease. Here, we will focus on Ptbp1, and hypothesize that activation of Ptbp1 in the endothelium modulates the inflammatory response seen in the progression of CVD through alternative splicing. In order to determine the role of Ptbp1 in inflammation and CVD, we propose to determine how Ptbp1 suppresses NFKB-mediated endothelial activation through in vitro approaches. We also propose to determine the role of Ptbp1 in the inflammatory response and progression in vivo by using a Ptbp1 inducible knockout (KO) system. We will be using both male and females for these experiments, as we know there are sex differences in plaque progression. The combination of these experiments will provide more information towards the ultimate goal of modulating the inflammatory response associated with CVD, and potentially, create better treatment options for those diagnosed with CVD.
|Program type||Predoctoral Fellowship|
|Effective start/end date||01/01/2020 → 12/31/2021|