Tension-induced SGK-1 Signaling in AAA

AAA 中张力诱导的 SGK-1 信号转导

基本信息

批准号：
9914887
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
项目类别：
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/9914887
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 Cultured Cells 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 cardiovascular risk factor career cytokine digital in vivo inhibitor/antagonist macrophage migration monocyte mortality mortality risk mouse model new therapeutic target response skills transcription factor vascular inflammation

项目摘要

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% 的美国人患有高血压目前受到影响。血压升高对主动脉壁重塑的影响显着对一般血管疾病，特别是动脉瘤形成的影响。血管紧张素II (AngII) 是一种有效的血管活性肽，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) 可增加主动脉壁内巨噬细胞的数量。有趣的是，腹主动脉瘤（AAA）患者也始终表现出升高的血浆和主动脉组织中 IL-6 的水平以及密集的巨噬细胞浸润。定义张力引起的驱动细胞因子产生的激酶对于确定 AAA 药物治疗的潜在靶点至关重要。最近的有证据表明血清和糖皮质激素诱导激酶 1 (SGK-1) 是一种机械敏感激酶导致内膜增生、动脉粥样硬化和肺动脉高压及其下游多种转录因子的调节可以调节 IL-6 和 MCP-1 的产生。因此，它是假设 HTN 促进 VSMC 激活 SGK-1，产生促炎细胞因子，积累巨噬细胞以促进 AAA 生长。第一个具体目标将分析张力引起的 SGK-1 从 C57Bl/6 野生型和 SGK-1 敲除收获的主动脉 VSMC 的激活和细胞因子表达 (SGK-1KO) 小鼠。这种条件培养基通过刺激单核细胞/巨噬细胞迁移的能力渗透膜也将被评估。在第二个目标中，诱导 HTN 的 C57Bl/6 和 SGK-1KO 小鼠（通过 AngII 输注）将评估 SGK-1 的激活、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 活性的依赖性将通过用选择性 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。第三个具体目标将重点关注 SGK-1 在启动和传播 AAA 形成中的作用采用经过验证的 CaCl2 诱导 AAA 模型并使用 EMD638683 治疗小鼠。这最终程序将评估 AAA 直径以及目标细胞因子和蛋白酶的产生。机会将通过在两者中诱导 HTN 和并发 AAA 来探索升高的张力以增强这种效果小鼠品系并进行平行生化分析。通过在 HTN 之间建立此链接，炎症，以及通过 SGK-1 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轻腹主动脉的动脉瘤变性。而且，该项目中概述的实验将为鲁迪博士提供一个利用以下资源的机会 MUSC 和心血管研究实验室扩大她的研究方法，发展指导素质，提高她的批判性思维能力，并增强她的资助能力，推动她走向职业生涯独立研究员。