Augmentation of Tissue Perfusion with Ultrasound-mediated Cavitation

用超声介导的空化增强组织灌注

• 批准号: 10650238
• 负责人: Jonathan R Lindner
• 金额: $ 51.22万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-12 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10650238
• 关键词: 3-Dimensional; 3D ultrasound; Acoustics; Acute; Address; Adenosine; Adenosine A2B Receptor; Affect; Age; Animal Model; Antiinflammatory Effect; Area; Atherosclerosis; Award; Blood Vessels; Blood flow; Caliber; Cardiovascular Diseases; Catheters; Chronic; Chronic Disease; Clinical Trials; Clinical Trials Design; Coagulation Process; Complication; Contrast Media; Convection; Coronary Arteriosclerosis; Coronary artery; Cytolysis; Development; Diabetes Mellitus; Diagnostic Imaging; Diffuse; Disease; Distal; Dose; Elements; Encapsulated; Endothelial Cells; Endothelium; Erythrocytes; Foundations; Frequencies; Funding; Gene-Modified; Grant; Health Care Costs; Heart; Heart failure; Human; Human Biology; Hyperlipidemia; Infarction; Inflammation; Ischemia; Isolated limb perfusion; Knowledge; Left Ventricular Dysfunction; Leg; Leg Ulcer; Limb structure; Lung; Maps; Mediating; Mediator of activation protein; Methods; Microbubbles; Microcirculation; Modeling; Morbidity - disease rate; Motion; Mus; Muscle; Muscle relaxation phase; Myocardial Ischemia; Myocardial perfusion; Myocardium; Pathway interactions; Patients; Perfusion; Peripheral; Peripheral arterial disease; Physiologic pulse; Pilot Projects; Pre-Clinical Model; Primates; Prostaglandins; Protocols documentation; Pulmonary Embolism; Pulmonary Vascular Resistance; Receptor Signaling; Regional Perfusion; Reperfusion Therapy; Rest; Risk; Risk Factors; Role; Scheme; Signal Transduction; Skeletal Muscle; Smooth Muscle; Syndrome; System; Techniques; Testing; Therapeutic; Thrombosis; Tissue Preservation; Tissue Viability; Tissues; Ultrasonic Therapy; United States; Vascular Diseases; Vascular resistance; Vasodilation; Vasospasm; acute coronary syndrome; atherosclerosis risk; base; clinical diagnostics; clinical effect; contrast enhanced; critical limb Ischemia; design; frailty; improved; inhibitor; limb ischemia; mortality; mouse model; necrotic tissue; nonhuman primate; novel; novel therapeutic intervention; preconditioning; pressure; prevent; receptor; sex; thrombotic; ultrasound; volunteer; wound healing

SUMMARY Ultrasound (US) is used for a variety of therapeutic applications. Over a range of different frequencies and powers, US has been shown to produce to produce modest increases in arterial diameter and tissue perfusion in animal models of limb and myocardial ischemia. In the initial funding period for this award, we described how the combination of US with microbubble (MB) contrast agents that undergo inertial cavitation during high-power contrast-enhanced US (CEU) produces much greater augmentation of limb skeletal muscle perfusion (up to 10-fold) than US alone. Brief CEU cavitation protocols were found to reverse limb ischemia for >24 hrs in animal models, and a clinical trial in patients with peripheral artery disease (PAD) confirmed that MB cavitation increases limb perfusion by several fold. In the course of our studies, optimal conditions for these bioeffects were investigated which mandated us to design novel US pulse schemes and 3-D exposure capability. From a mechanistic standpoint, we carefully mapped pathways responsible for cavitation-induced flow augmentation which rely on shear-mediated ATP release from endothelial cells and erythrocytes, with secondary purinergic vasodilation through downstream mediators (NO, prostaglandins, adenosine). Knowledge of the optimal conditions and mechanistic underpinnings is critical for our current efforts to apply cavitation and activation of ATP channels to treat ischemic disease by augmenting flow or by other potentially beneficial anti-thrombotic and anti-inflammatory effects of purinergic signaling. The overall aim of this renewal is to leverage knowledge from the first funding period in order to explore the therapeutic role of cavitation and non-cavitation US for acute and chronic ischemic syndromes. In Aim 1 preclinical models will be used to determine whether limb flow-augmentation from MB cavitation using previously-optimized pulse schemes can: (a) prevent tissue necrosis in acute ischemia, with a particular focus on the effect of clinical variables (age, sex, hyperlipidemia, diabetes), and (b) improve wound healing and limb function in chronic disease. The functional role of purinergic vascular signaling will be evaluated by using inhibitor strategies or gene--modified models. In Aim 2 we will determine whether MB cavitation directly augments myocardial perfusion in acute MI using murine models that allow us to manipulate purinergic pathways, and in primate models that more closely resemble human biology. We will also study how US-mediated ATP release has the potential to mitigate inflammation, and microvascular thrombosis upon reperfusion. In Aim 3 we will test whether US energy from multi-element high-power intra- arterial catheters increases downstream perfusion through shear-mediated purinergic pathways. This Aim is based on evidence that therapeutic US catheters used in patients with pulmonary embolism can reduce pulmonary vascular resistance even without clot lysis. Our proposal represents the translational steps for development of non-invasive therapies for acute and chronic vascular diseases and will form the basis for the design of clinical trials that we plan to initiate as the key unsolved issues are addressed.

概括 超声（US）用于多种治疗应用。超过一系列不同的频率和 美国已经显示出可产生的美国产生动脉直径和组织灌注的适度增加 在肢体和心肌缺血的动物模型中。在该奖项的最初资助期内，我们描述了如何 我们与微泡（MB）对比剂的组合，在大功率期间经历惯性空化 对比增强的美国（CEU）产生了更大的肢体骨骼肌肉灌注的增强（最多 比我们一个人十倍）。发现简短的CEU空化方案可逆转肢体缺血，> 24小时 动物模型和外周动脉疾病（PAD）患者的临床试验证实了MB气氮 将肢体灌注增加几倍。在我们的研究过程中，这些生物效应的最佳条件 研究了该研究要求我们设计新型的US脉搏方案和3-D暴露能力。来自 机械的角度，我们仔细映射了负责气腔诱导的流量增大的途径 依赖于剪切介导的ATP从内皮细胞和红细胞释放，次生嘌呤能 通过下游介质（不，前列腺素，腺苷）进行血管舒张。最佳知识 条件和机械基础对于我们目前的空化和激活至关重要 通过增加流动或其他潜在有益的抗脉动的ATP通道来治疗缺血性疾病 和嘌呤能信号传导的抗炎作用。这种更新的总体目的是利用知识 从第一个资金期开始，以探索空化和非浪费的治疗作用 急性和慢性缺血综合征。在AIM 1中，将使用临床前模型来确定是否肢体 使用先前优化的脉搏方案从MB空化的流动仪可以：（a）防止组织 急性缺血的坏死，特别关注临床变量的作用（年龄，性别，高脂血症， 糖尿病）和（b）改善慢性疾病中的伤口愈合和肢体功能。嘌呤能的功能作用 血管信号传导将通过使用抑制剂策略或基因改性模型来评估。在目标2中，我们将 确定使用使用鼠模型直接增强急性MI中的心肌灌注 允许我们操纵嘌呤能途径，并在更像人类生物学的灵长类动物模型中。 我们还将研究US介导的ATP释放如何减轻炎症和微血管 再灌注后血栓形成。在AIM 3中，我们将测试US来自多元素高功率内部的能源 动脉导管通过剪切介导的嘌呤能途径增加下游灌注。这个目标是 基于证据表明，在肺栓塞患者中使用的治疗性美国导管可以减少 即使没有凝块裂解，肺血管抗性也是如此。我们的建议代表了转化步骤 开发针对急性和慢性血管疾病的非侵入性疗法，将构成 我们计划在关键的未解决问题的关键问题上进行临床试验的设计。