Lipid macropinocytosis: a novel target in atherosclerotic cardiovascular disease

脂质巨胞饮作用：动脉粥样硬化性心血管疾病的新靶点

• 批准号: 10401923
• 负责人: Gabor Csanyi
• 金额: $ 38.5万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10401923
• 关键词: Actin-Binding Protein; Affinity; Antibodies; Antigen Presentation; Aorta; Apolipoprotein E; Area; Arterial Fatty Streak; Arteries; Atherosclerosis; Attenuated; Binding; Blocking Antibodies; CD36 gene; CD47 gene; Cardiovascular system; Cause of Death; Cell Fractionation; Cell membrane; Cells; Cholesterol; Chronic; Confocal Microscopy; Data; Development; Dissociation; Exhibits; Extracellular Matrix Proteins; Flow Cytometry; Fluorescence; Foam Cells; Genetic; High Pressure Liquid Chromatography; Human; In Vitro; Inflammation; Inflammatory; Knock-out; Knockout Mice; Knowledge; Link; Lipid-Laden Macrophage; Lipids; Lipoproteins; Low Density Lipoprotein Receptor; Low Density Lipoprotein oxidation; Low-Density Lipoproteins; Mediating; Membrane; Microscopy; Modification; Mus; NHE1; Other Genetics; Pathogenesis; Pathway interactions; Pharmacology; Phenotype; Phospholipase C; Phosphoric Monoester Hydrolases; Physiological; Play; Process; Protein Dephosphorylation; Protein Isoforms; Proteins; Receptor Signaling; Reporting; Resolution; Role; Signal Transduction; Small Interfering RNA; Smooth Muscle Myocytes; Subendothelial Layer; Techniques; Testing; Thrombospondin 1; Time; United States; Vascular Smooth Muscle; Western Blotting; Woman; cofilin; cost; health care delivery; in vivo; inhibitor; innovation; macrophage; men; mouse genetics; mutant; nanoparticle; novel; overexpression; platelet-derived growth factor BB; protein aminoacid sequence; receptor; scavenger receptor; therapeutic target; tool; uptake; vascular inflammation

Project Summary Atherosclerosis, the main underlying cause of death worldwide, is characterized by chronic inflammation and accumulation of lipids in the arterial wall. Excessive lipid accumulation by macrophages (MΦs) and vascular smooth muscle cells (SMCs) plays a key role in the initiation and progression of atherosclerosis. It is generally accepted that atherosclerosis arise from LDL modification in the arterial wall and its subsequent internalization by MΦs and SMCs through a variety of scavenger receptors. The role of scavenger receptor-independent lipid uptake in atherosclerosis, the physiological factors stimulating this process, and the signaling mechanisms involved remain poorly characterized. We reported that matrix protein thrombospondin-1 (TSP1) stimulates direct, scavenger receptor-independent uptake of unmodified, native LDL (nLDL) in MΦs. TSP1 via its cognate receptor CD47 activates actin-binding protein cofilin, leading to macropinocytosis of nLDL, and excessive cholesterol accumulation. The signaling mechanisms downstream of CD47 that stimulate macropinocytosis are unknown. Although phospholipase C (PLC) and slingshot phosphatase 1 (SSH1) have been shown to activate cofilin, their roles in TSP1-induced macropinocytosis have not yet been investigated. Moreover, the ability of TSP1-CD47 signaling to stimulate MΦ macropinocytosis in atherosclerotic vessels in vivo and the significance of lipid macropinocytosis in the pathogenesis of atherosclerosis remain to be determined. Our novel preliminary data show that TSP1 and CD47 knockout mice are protected from atherosclerosis and the macropinocytosis inhibitor EIPA decreases atherosclerotic lesion formation in hypercholesterolemic mice. We hypothesize that TSP1 via CD47 promotes lipid macropinocytosis in the arterial wall, contributing to lipid accumulation and the pathogenesis of atherosclerosis. The hypothesis will be tested via the following aims: (1) examining for the first time whether CD47 receptor signaling in MΦs stimulates macropinocytosis via PLC- and SSH1-mediated cofilin activation and contributes to atherosclerosis development; (2) exploring whether MΦs internalize lipoproteins via macropinocytosis in atherosclerotic arteries in vivo and that deletion of NHE1 (major target of EIPA) specifically in MΦs attenuates atherosclerosis, and (3) investigating whether TSP1 binding to CD47 stimulates macropinocytosis in MΦ-like SMCs via Nox1-mediated cofilin activation. The proposal will employ global and cell-specific knockout mice, and other genetic tools to test the hypothesis. Specific targeting of CD47 via multiple approaches (antibody blockade, siRNA/morpholino silencing, and CD47 activating peptide sequences) will provide confirmation of results obtained in genetic mutants. Multiple complementary techniques will be used to study macropinocytosis in vitro (pharmacological, genetic, fluorescence/high-resolution microscopy) and in vivo (cofilin mutants, AngioSPARK 680, MΦ-specific NHE1 knockouts). This innovative proposal has the potential to reveal important new mechanisms of lipid internalization and provide a paradigm shift in our knowledge about how atherosclerosis develops.

项目总结

项目成果

PKCδ stimulates macropinocytosis via activation of SSH1-cofilin pathway.

• DOI: 10.1016/j.cellsig.2018.09.018
• 发表时间: 2019-01
• 期刊: Cellular signalling
• 影响因子: 4.8
• 作者: Singla B;Lin HP;Ghoshal P;Cherian-Shaw M;Csányi G
• 通讯作者: Csányi G

Nf1 heterozygous mice recapitulate the anthropometric and metabolic features of human neurofibromatosis type 1.

• DOI: 10.1016/j.trsl.2020.08.001
• 发表时间: 2021-03
• 期刊: Translational research : the journal of laboratory and clinical medicine
• 作者: Tritz R;Benson T;Harris V;Hudson FZ;Mintz J;Zhang H;Kennard S;Chen W;Stepp DW;Csanyi G;Belin de Chantemèle EJ;Weintraub NL;Stansfield BK
• 通讯作者: Stansfield BK

Sildenafil improves vascular endothelial function in patients with cystic fibrosis.

• DOI: 10.1152/ajpheart.00301.2018
• 发表时间: 2018-11
• 期刊: American journal of physiology. Heart and circulatory physiology
• 作者: Paula Rodriguez-Miguelez;N. Lee;M. Tucker;G. Csányi;K. McKie;C. Forseen;R. Harris