Tension-induced SGK-1 Signaling in AAA

AAA 中张力诱导的 SGK-1 信号转导

• 批准号: 10368068
• 负责人: Jean Marie Ruddy
• 金额: $ 17.65万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-14 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10368068
• 关键词: Abdominal Aortic Aneurysm; Affect; American; Aneurysm; Angiotensin II; Aorta; Aortic Aneurysm; Atherosclerosis; Attenuated; Automobile Driving; Biochemical; Biomechanics; Blood Pressure; Bone Marrow; CCL2 gene; Caliber; Cardiovascular system; Cell Culture Techniques; Cell Line; Cell Membrane Permeability; Cells; Critical Thinking; Culture Media; Dependence; Development; Disease; Enzyme-Linked Immunosorbent Assay; Epidemiology; Experimental Designs; Exposure to; Flow Cytometry; Future; Gelatinase B; Glucocorticoids; Growth; Harvest; Hyperplasia; Hypertension; ITGAM gene; Immunoblot Analysis; In Vitro; Infiltration; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Infusion procedures; Innovative Therapy; Interleukin-6; Knock-out; Knockout Mice; Laboratories; Laboratory Research; Life; Link; Measures; Mechanics; Mediating; Mentorship; Microscopy; Modeling; Molecular; Mouse Strains; Mus; Pathology; Pathway interactions; Patients; Peptide Hydrolases; Peptides; Pharmacotherapy; Phosphotransferases; Plasma; Play; Population; Procedures; Production; Proteins; Pulmonary Hypertension; Regulation; Research Methodology; Research Personnel; Resources; Role; Rupture; Serum; Signal Transduction; Small Interfering RNA; Smooth Muscle Myocytes; Stains; Stimulus; Stretching; Stroke; Tissues; Unstable angina; Vascular Diseases; Vascular Smooth Muscle; Vascular remodeling; Wild Type Mouse; Work; abdominal aorta; blood pressure elevation; cardiovascular risk factor; career; cytokine; digital; hypertensive; in vivo; inhibitor; inhibitor therapy; macrophage; migration; monocyte; mortality; mortality risk; mouse model; new therapeutic target; response; skills; transcription factor; vascular inflammation

Hypertension (HTN) is a major risk factor for cardiovascular mortality and greater than 30% of Americans are currently affected. The impact of elevated blood pressure on aortic wall remodeling has significant implications for vascular disease in general, and aneurysm formation specifically. AngiotensinII (AngII) is a potent vasoactive peptide and contributes to vascular inflammation by stimulating production of interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) to augment the population of macrophages within the aortic wall. Interestingly, patients with abdominal aortic aneurysms (AAA) have also consistently demonstrated elevated plasma and aortic tissue levels of IL-6, along with dense macrophage infiltration. Defining the tension-induced kinase driving cytokine production is vital to identifying a potential target for pharmacotherapy of AAA. Recent evidence has identified serum and glucocorticoid inducible kinase-1 (SGK-1) as a mechanically sensitive kinase that contributes to intimal hyperplasia, atherosclerosis, and pulmonary hypertension, and its downstream regulation of several transcription factors can modulate the production of IL-6 and MCP-1. Therefore, it is hypothesized that HTN promotes VSMC activation of SGK-1 to produce pro-inflammatory cytokines that accumulate macrophages to propagate AAA growth. The first specific aim will analyze tension-induced SGK-1 activation and cytokine expression from aortic VSMCs harvested from C57Bl/6 wild-type and SGK-1 knockout (SGK-1KO) mice. The ability of this conditioned media to stimulate monocyte/macrophage migration through a permeable membrane will also be assessed. In the second aim, C57Bl/6 and SGK-1KO mice with induced HTN (via AngII infusion) will be evaluated for the activation of SGK-1, production of pro-inflammatory cytokines IL-6 and MCP-1, and accumulation of macrophages. Dependence of this inflammatory response on SGK-1 activity will be further explored by treating wild-type mice subjected to induced HTN with the selective SGK-1 inhibitor EMD638683. The third specific aim will focus on the role of SGK-1 in initiating and propagating AAA formation by employing a validated model of AAA induction with CaCl2 application and treating mice with EMD638683. The terminal procedure will evaluate AAA diameter and production of target cytokines and proteases. The opportunity for elevated tension to augment this effect will be explored by inducing HTN and concurrent AAA in the two mouse strains and conducting parallel biochemical analysis. By establishing this link between HTN, inflammation, and the initiation of degradative vascular remodeling through the activity of SGK-1, future studies may utilize targeted inhibitor therapies to attenuate aneurysmal degeneration in the abdominal aorta. Moreover, the experimentation outlined in this project will provide an opportunity for Dr. Ruddy to engage the resources of MUSC and the Cardiovascular Research Laboratory to expand her research methodology, develop mentorship qualities, enhance her critical-thinking skills, and augment her grantsmanship to propel her toward a career as an independent researcher.

高血压（HTN）是心血管死亡的主要危险因素，超过30%的美国人 目前受到影响。血压升高对主动脉壁重构的影响具有显著性 对血管疾病的影响，特别是动脉瘤的形成。血管紧张素II（AngII）是一种有效的 血管活性肽，并通过刺激白细胞介素-6（IL-6）的产生而导致血管炎症， 单核细胞趋化蛋白-1（MCP-1）增加主动脉壁内巨噬细胞的数量。 有趣的是，患有腹主动脉瘤（AAA）的患者也一直表现出升高的 血浆和主动脉组织IL-6水平，沿着致密巨噬细胞浸润。定义张力引起的 激酶驱动细胞因子的产生对于确定AAA药物治疗的潜在靶点至关重要。最近 有证据表明血清和糖皮质激素诱导的激酶-1（SGK-1）是一种机械敏感的激酶 导致内膜增生、动脉粥样硬化和肺动脉高压，及其下游 几种转录因子的调节可以调节IL-6和MCP-1的产生。因此有 假设HTN促进SGK-1的VSMC活化以产生促炎细胞因子， 积聚巨噬细胞以传播AAA生长。第一个具体目标将分析张力诱导的SGK-1 从C57 B1/6野生型和SGK-1敲除收获的主动脉VSMC的活化和细胞因子表达 （SGK-1 KO）小鼠。这种条件培养基刺激单核细胞/巨噬细胞通过单核细胞/巨噬细胞膜迁移的能力被证实。 还将评估渗透膜。在第二个目标中，C57 B1/6和SGK-1 KO小鼠诱导HTN (via AngII输注）将评估SGK-1的活化、促炎细胞因子IL-6的产生 和MCP-1，以及巨噬细胞的积累。这种炎症反应对SGK-1活性的依赖 将通过用选择性SGK-1抑制剂治疗经受诱导HTN的野生型小鼠来进一步探索 EMD638683。第三个具体目标将侧重于SGK-1在启动和传播AAA形成中的作用 通过采用经验证的CaCl 2诱导AAA模型并用EMD 638683治疗小鼠。的 终末程序将评估AAA直径和靶细胞因子和蛋白酶产生。机会 对于张力升高，将通过诱导HTN和并发AAA来探索这种效应， 小鼠品系并进行平行生化分析。通过在HTN之间建立这种联系， 炎症，并通过SGK-1的活性启动降解性血管重塑，未来的研究 可以利用靶向抑制剂疗法来减弱腹主动脉中的平滑肌变性。此外，委员会认为， 本项目中概述的实验将为鲁迪博士提供一个机会， MUSC和心血管研究实验室，以扩大她的研究方法，发展导师 素质，提高她的批判性思维能力，并增加她的granitarian推动她走向职业生涯， 独立研究员。