Insulin-Like Growth Factor-1 and Atherosclerosis

项目总结/摘要 冠心病是全球心血管疾病的主要原因。尽管最佳治疗 许多患者仍然易受局部缺血事件的影响。虽然小动物模型已经证明了 为了有效地探索机制，迫切需要在大型动物模型中进行研究， 啮齿动物研究和人体试验，并开发新的疗法。我们已经证明胰岛素样生长因子-1 在Apoe-/-小鼠和Rapacz中，IGF-1降低动脉粥样硬化负荷并促进斑块稳定性特征 患有家族性高胆固醇血症的猪（FH猪）。我们的新发现表明，IGF-1减少了 猪冠状动脉中衰老细胞的数量，包括衰老的SMC样细胞和MF样细胞 动脉粥样硬化斑块，特别是纤维帽（FC）。细胞衰老被认为是 在衰老和慢性病发展中的作用。然而，IGF-1与细胞衰老的关系 和动脉粥样硬化疾病几乎是未知的。衰老细胞促进动脉粥样硬化形成和纤维帽 在小鼠模型中，细胞变薄，但没有关于细胞衰老在动脉粥样硬化形成中的因果作用的信息。 大型动物模型或人类。使用scRNA-seq分析来自ApoE-/-小鼠和空间 通过对猪牙菌斑的转录组学分析，我们显示了衰老相关基因的高水平表达。 分泌表型（SASP）因子IGF结合蛋白-7（IGFBP 7），一种IGF-1抑制剂，在纤维帽中， 主要定位于SMC样细胞，特别是纤维肌细胞。衰老分数的升高 与纤维肌细胞和高IGFBP 7表达相关。我们假设衰老细胞抑制了 SASP诱导的IGF-1抵抗降低了IGF-1的抗动脉粥样硬化作用。 我们的数据表明，来自衰老培养SMC的条件培养基抑制SMC中的IGF 1 R信号， 通过抗IGFBP 7抗体逆转该效应。我们的总体目标是证明去除衰老细胞 使用衰老清除剂ABT 263将减少大型动物模型中的动脉粥样硬化， IGF-I的作用我们还将使用功能丧失的小鼠模型证明IGFBP 7在IGF-1抗性中的作用。 模型，并进一步探索机制，使用体外研究。 具体目的1：检验在大型动物中使用衰老清除剂清除衰老细胞的假设 动脉粥样硬化模型将减少动脉粥样硬化负荷，并增强IGF-1减少 动脉粥样硬化负担和促进斑块稳定性。scRNA-seq，空间转录组学，多标记 组织学和激光捕获显微切割（LCM）将用于解剖机制。 具体目标2：具体目标2：证明SMC样细胞中IGFBP 7的遗传剥夺 增强IGF-1的抗动脉粥样硬化作用。我们将使用SMC选择性IGFBP 7缺陷小鼠，scRNA- 序列分析和体外模型来剖析机制。

PROJECT SUMMARY / ABSTRACT Coronary heart disease is a primary contributor to cardiovascular disease worldwide. Despite optimal treatment many patients remain vulnerable to ischemic events. While small animal models have proven extraordinarily effective at exploring mechanisms, studies in large animal models are critically needed, as a bridge between rodent studies and human trials, and to develop new therapies. We have shown that insulin-like growth factor-1 (IGF-1) reduces atherosclerotic burden and promotes features of plaque stability in Apoe-/- mice and in Rapacz swine with familial hypercholesterolemia (FH pigs). Our novel findings indicate that IGF-1 reduces the number of senescent cells, including senescent SMC-like and MF-like cells in pig coronary atherosclerotic plaques, in particular in the fibrous cap (FC). Cellular senescence is thought to play a vital role in aging and in the development of chronic disease. However, the relation between IGF-1, cell senescence and atherosclerotic disease is virtually unknown. Senescent cells contribute to atherogenesis and fibrous cap thinning in mouse models, but there is no information on the causal role of cell senescence in atherogenesis in large animal models or in humans. Using scRNA-seq analysis of aortas from Apoe-/- mice and spatial transcriptomics analysis of porcine plaque we show high-level expression of the senescence-associated secretory phenotype (SASP) factor IGF binding Protein-7 (IGFBP7), an IGF-1 inhibitor, in the fibrous cap, primarily localized to SMC-like cells, particularly fibromyocytes. Elevated senescence scores are strongly associated with fibromyocytes and high IGFBP7 expression. We hypothesize that senescent cells inhibit IGF-1 signaling and that SASP-induced IGF-1 resistance reduces anti-atherosclerotic effects of IGF-1. Our data shows that conditioned medium from senescent cultured SMC inhibits IGF1R signaling in SMC, an effect reversed by anti-IGFBP7 antibody. Our overall goal is to demonstrate that removal of senescent cells using a senolytic, ABT263, will reduce atherosclerosis in a large animal model and potentiate anti-atherosclerotic effects of IGF-I. We will also demonstrate the role of IGFBP7 in IGF-1 resistance using a loss-of-function murine model, and further explore mechanisms using in vitro studies. Specific Aim 1: Test the hypothesis that clearance of senescent cells using a senolytic in a large animal model of atherosclerosis will reduce atherosclerotic burden and potentiate IGF-1 ability to reduce atherosclerotic burden and promote plaque stability. scRNA-seq, spatial transcriptomics, multi-marker histology, and laser capture microdissection (LCM) will be used to dissect mechanisms. Specific Aim 2: Specific Aim 2: Demonstrate that genetic deprivation of IGFBP7 in SMC-like cells enhances anti-atherosclerosis effects of IGF-1. We will use SMC-selective IGFBP7-deficient mice, scRNA- seq analysis and in vitro models to dissect mechanisms.