C-KIT SIGNALING IN COLLATERALS REMODELING

侧枝循环重塑中的 C-KIT 信号传导

• 批准号: 10321566
• 负责人: Roberta Marques Lassance Soares
• 金额: $ 12.64万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-17 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10321566
• 关键词: Alternative Therapies; American; Amputation; Anatomy; Arteries; Biology; Blood; Blood Vessels; Blood Volume; Blood capillaries; Blood flow; Bypass; Cell Proliferation; Coronary; Defect; Disease; Ensure; FBXO32 gene; Failure; Functional disorder; GKLF protein; Gangrene; Goals; Growth; Hematopoietic; Hindlimb; Histology; Human; Hypoxia; Impairment; Intervention; Ischemia; Knock-in; Knockout Mice; Limb structure; Lower Extremity; Mediating; Membrane; Modeling; Molecular; Morbidity - disease rate; Mus; Mutant Strains Mice; Mutation; Operative Surgical Procedures; Outcome Study; Pain; Pathway interactions; Patients; Periodicity; Peripheral arterial disease; Pharmacology; Phase; Phenotype; Physiologic pulse; Physiological; Play; Procedures; Process; Protein Kinase C; Proteomics; Proto-Oncogene Protein c-kit; Receptor Protein-Tyrosine Kinases; Recovery; Regulation; Rest; Risk; Role; Secondary to; Signal Transduction; Smooth Muscle Myocytes; Stenosis; Tamoxifen; Testing; Tissues; Training; Transgenic Model; Transgenic Organisms; Ubiquitination; United States; Vascular remodeling; angiogenesis; artery occlusion; cell motility; conditional knockout; critical limb Ischemia; effective therapy; experimental study; gain of function; imaging modality; improved; limb ischemia; loss of function; microCT; mutant; new therapeutic target; novel; novel therapeutics; patient population; prevent; reconstitution; restoration; transcriptome sequencing; vascular stress

TITLE: C-KIT SIGNALING IN COLLATERALS REMODELING Critical limb ischemia (CLI) is the most advanced form of peripheral arterial disease. At the moment, endovascular procedures and bypass surgeries are the only effective treatments for limb revascularization. However, a significant proportion of CLI patients are not good candidates for these interventions, requiring primary amputation as the main treatment option. Therefore, an effective pharmacological strategy that prevents CLI and its devastating consequences represents a much- needed alternative for this patient population. Arteriogenesis is a physiological compensatory process in which pre-existing collaterals enlarge and serve as natural bypasses to severe occlusion of arteries. We have recently identified that the c-Kit receptor tyrosine kinase plays a key role in the remodeling of collaterals during arteriogenesis. We found that defective c-Kit function compromises blood flow recovery after hindlimb ischemia, which was not resolved with hematopoietic reconstitution of c-Kit activity. We have confirmed defective arteriogenesis in c-Kit mutant mice compared to controls. Mechanistically, we advanced our understanding of how the c-Kit/Kruppel-like factor 4 (KLF4) pathway orchestrates collateral remodeling. Therefore, our central hypothesis is that c-Kit/KLF-4 signaling controls the recovery of the smooth muscle cell (SMC) contractile phenotype at the maturation phase of arteriogenesis to prevent excessive remodeling and narrowing of collaterals. We propose two Specific Aims (SA) to test our hypothesis. In SA1, we will demonstrate the involvement of vascular c-Kit signaling in arteriogenesis. We will investigate whether inactivation or activation of c-Kit specifically in SMCs will lead to dysfunction or optimal arteriogenesis in unique transgenic models of loss- and gain- of-function of c-Kit, respectively. We will also identify molecular mechanisms that can be altered by the loss- or gain-of-function on SMC c-Kit. In SA2, we will dissect the molecular pathways upstream and downstream of c-Kit in SMCs. First, we will investigate whether cyclic strain dictates the oscillatory expression of the c-Kit receptor by activating protein kinase C, leading to c-Kit suppression. Next, we will determine whether c-Kit inhibits KLF4 through FBXO32-mediated ubiquitination, thereby restoring the contractile SMC phenotype and preventing defective remodeling. RELEVANCE: Approximately 80,000 major lower-extremity amputations occur in the United States every year due to CLI. In this study, we will identify novel therapeutic targets to improve arteriogenesis and prevent or alleviate the devastating effects of CLI. Moreover, we will identify the molecular mechanism that dictates phenotypic switching in SMCs, which may be applicable to the understanding and treatment of other vascular occlusive diseases.

标题：抵押品重塑中的C-KIT信号传导 关键的肢体缺血（CLI）是最先进的外周动脉疾病。眼下， 血管内手术和旁路手术是肢体的唯一有效治疗方法 血运重建。但是，很大一部分的CLI患者对这些并不是好的候选者 干预措施，需要主要截肢为主要治疗方案。因此，有效 防止CLI及其毁灭性后果的药理策略代表了一个非常重要的 该患者人群所需的替代方案。动脉生成是一种生理补偿过程 在其中，预先存在的侧边扩大并充当自然旁路，以严重阻塞动脉。 我们最近确定，C-kit受体酪氨酸激酶在重塑中起关键作用 动脉生成期间的侧支。我们发现有缺陷的C-KIT功能会损害血流 后肢局部缺血后的恢复，而C-KIT无法解决造血的重构 活动。我们已经证实了与对照组相比，C-KIT突变小鼠中的动脉生成缺陷。 从机械上讲，我们对C-Kit/Kruppel样因子4（KLF4）途径的理解提出了了解 策划抵押改建。因此，我们的中心假设是C-KIT/KLF-4信号传导 控制平滑肌细胞（SMC）收缩表型在成熟阶段的恢复 动脉生成以防止侧支过度重塑和狭窄。我们提出了两个特定的 目的（SA）检验我们的假设。在SA1中，我们将展示血管C-KIT的参与 动脉生成中的信号传导。我们将调查C-KIT的灭活或激活是专门的 SMC将导致在损失和增益的独特转基因模型中导致功能障碍或最佳动脉生成 C-Kit的功能分别。我们还将确定可以通过 SMC C-KIT的损失或功能损益。在SA2中，我们将剖析上游的分子途径，并 SMC中的C-Kit下游。首先，我们将研究环状应变是否决定振荡 通过激活蛋白激酶C的C-KIT受体表达，导致C-KIT抑制。接下来，我们 将确定C-KIT是否通过FBXO32介导的泛素化抑制KLF4，从而恢复 收缩的SMC表型和预防有缺陷的重塑。 相关性：美国发生了大约80,000个主要的低超级截肢 每年由于CLI。在这项研究中，我们将确定新的治疗靶标以改善动脉生成 并防止或减轻CLI的破坏性影响。此外，我们将确定分子 指示SMC中表型转换的机制，这可能适用于理解 以及其他血管闭塞性疾病的治疗。