NKA/CD36 signaling in adipocytes promotes oxidative stress and drives chronic inflammation in atherosclerosis

脂肪细胞中的 NKA/CD36 信号传导促进氧化应激并驱动动脉粥样硬化的慢性炎症

基本信息

批准号：
10655793
负责人：
Yiliang Chen
金额：
$ 54.72万
依托单位：
MEDICAL COLLEGE OF WISCONSIN
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-04-01 至 2027-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10655793
关键词：
ATPase inhibitory protein Adipocytes Adipose tissue Amino Acids Animal Model Apolipoprotein E Arterial Fatty Streak Arteries Atherosclerosis Attenuated Binding Biochemical Biological Assay CD36 gene Cause of Death Cells Chronic Complex Data Development Distant Dyslipidemias Foam Cells Gene Expression Gene Expression Profiling Genetic Goals Hormones In Vitro Incubated Inflammation Inflammatory Injections Ions K ATPase Knockout Mice Label Lentivirus Vector Ligands Link Lipids Location Macrophage Macrophage Activation Mediating Mediator Membrane Metabolic Methods MicroRNAs Mitochondria Modeling Molecular Molecular Conformation Mus Myocardial Infarction N Domain Oxidative Stress Pathway interactions Peptide Initiation Factors Peptides Phenotype Phosphotransferases Play Production Proteins Proteome Publishing Pump Reagent Reporter Risk Factors Role Signal Transduction Stroke Study models Techniques Testing Therapeutic Therapeutic Intervention Tissues Work adipocyte biology adipokines atherogenesis cell type chronic inflammatory disease cytokine diagnostic biomarker driving force exosome immune activation improved in vivo limb ischemia limb loss lipid metabolism lipidome lipidomics molecular phenotype monocyte mouse model new therapeutic target next generation novel novel diagnostics novel therapeutic intervention oxidant stress oxidized low density lipoprotein paracrine receptor release factor response scaffold scavenger receptor src-Family Kinases trafficking transcriptome sequencing

项目摘要

Atherosclerosis (AS) is a chronic inflammatory disease of medium and large arteries and remains the leading cause of death worldwide from its sequelae of heart attack, stroke and limb loss. During AS progression chronic activation of immune cells in the vessel wall, especially macrophages, leads to formation of lipid-loaded foam cells which become the major component of atherosclerotic plaque. The goal is to discover molecular mechanisms through which dyslipidemia and oxidative stress, which are major risk factors for AS, are linked to chronic macrophage activation via dysregulated function of fat cells (adipocytes). The proposal will explore how adipocyte-derived exosomes (Ad-Exo) carrying specific pro-atherogenic cargo such as miRNAs, are generated under oxidative stress, and how they activate macrophages. Focus is CD36, type II scavenger receptor highly expressed in adipocytes and macrophages that acts as a receptor for the atherogenic ligand oxidized LDL (oxLDL). The oxLDL/CD36 signaling axis creates an inflammatory paracrine loop between macrophages and adipocytes and facilitates oxidative stress and pro-inflammatory cytokine secretion through Src family kinase (SFK) activation. Na/K-ATPase (NKA) α1 subunit serves both as a CD36 co- receptor and a scaffold for the SFK, allowing conformational changes in the NKA to activate membrane bound SFK and initiate signaling cascades, a mechanism distinct from its well-understood pumping function. Hypothesis of this proposal is that activation of NKA/CD36 signaling in adipocytes produces oxidative stress that causes release of adipokines and exosomes (Ad-Exo). These released factors initiate and augment AS by stimulating macrophages. To test this hypothesis, 3 specific aims have been developed. The first will test the hypothesis that adipocyte NKA/CD36 signaling complex promotes AS through production of cellular oxidative stress leading to abnormal adipokines/exosome secretion. The approach will include use of the apoe null mouse model and lentiviral vectors to deliver cell-specific NaKtide, a peptide reagent derived from the NKA α1 domain that behaves as a specific inhibitor of the NKA/SFK pathway. Oxidant stress, AS plaque formation, and adipocyte gene expression will be assessed using state-of-the-art techniques, such as next generation RNASeq. The second aim will test whether Ad-Exo can modulate macrophage function in vitro and in vivo by characterizing the proteome, lipidome and miRNA profile of Ad-Exo released in response to oxidative stress and tracking their delivery to monocytes and AS plaque. A newly developed mouse model, GFP- CD63flox/Adipoq Cre mice will be used as an excellent Ad-Exo reporter animal model for these studies. The third aim will determine if Ad-Exo regulate macrophage lipid metabolism and mitochondrial function using sophisticated metabolic flux assays along with lipidomic and gene expression assays. Successful completion of this project will define an important concept that adipocyte CD36/NKA and downstream Ad-Exo secretion is a driving force for chronic macrophage activation in AS, thereby identifying novel therapeutic targets.

动脉粥样硬化（AS）是一种中大动脉的慢性炎症性疾病，目前仍然是导致动脉粥样硬化的主要原因 AS 进展期间心脏病发作、中风和肢体丧失的后遗症是全世界死亡的原因。血管壁中免疫细胞（尤其是巨噬细胞）的慢性激活导致脂质负载的形成泡沫细胞成为动脉粥样硬化斑块的主要成分，目标是发现分子。血脂异常和氧化应激（AS 的主要危险因素）与 AS 相关的机制该提案将探讨通过脂肪细胞（脂肪细胞）功能失调来慢性激活巨噬细胞。脂肪细胞衍生的外泌体（Ad-Exo）如何携带特定的促动脉粥样硬化货物（例如 miRNA）氧化应激下产生的巨噬细胞，以及它们如何激活巨噬细胞焦点是 CD36，II 型清道夫。在脂肪细胞和巨噬细胞中高度表达的受体，充当致动脉粥样硬化配体的受体氧化 LDL (oxLDL) oxLDL/CD36 信号轴在两者之间创建炎症旁分泌环。巨噬细胞和脂肪细胞，并通过促进氧化应激和促炎细胞因子的分泌 Src 家族激酶 (SFK) 激活 Na/K-ATP 酶 (NKA) α1 亚基既充当 CD36 共受体又充当 CD36 辅助受体。 SFK 的支架，允许 NKA 的构象变化激活膜结合的 SFK 和启动信号级联，这是一种与其众所周知的泵功能假设不同的机制。该提议认为，脂肪细胞中 NKA/CD36 信号传导的激活会产生氧化应激，从而导致释放这些释放的因子通过刺激来启动和增强 AS。为了检验这一假设，我们制定了 3 个具体目标。脂肪细胞 NKA/CD36 信号复合物通过产生细胞氧化应激促进 AS 导致脂肪因子/外泌体分泌异常该方法将包括使用 apoe null 小鼠。模型和慢病毒载体，用于递送细胞特异性 NaKtide，一种源自 NKA α1 结构域的肽试剂作为 NKA/SFK 通路的特异性抑制剂，抑制氧化应激、AS 斑块形成和将使用最先进的技术评估脂肪细胞基因表达，例如下一代 RNASeq 的第二个目标是测试 Ad-Exo 是否可以通过体外和体内调节巨噬细胞功能。表征因氧化应激而释放的 Ad-Exo 的蛋白质组、脂质组和 miRNA 谱并追踪它们向单核细胞和AS斑块的传递，这是一种新开发的小鼠模型，GFP-。 CD63flox/Adipoq Cre 小鼠将用作这些研究的优秀 Ad-Exo 报告动物模型。第三个目标是确定 Ad-Exo 是否调节巨噬细胞脂质代谢和线粒体功能复杂的代谢通量测定以及脂质组学和基因表达测定成功完成。该项目将定义一个重要的概念，即脂肪细胞 CD36/NKA 和下游 Ad-Exo 分泌是 AS 中慢性巨噬细胞激活的驱动力，从而确定新的治疗靶点。