tPA nanoconjugate for stroke therapy

用于中风治疗的 tPA 纳米缀合物

• 批准号: 10204139
• 负责人: VINOD D LABHASETWAR
• 金额: $ 41.35万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-30 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10204139
• 关键词: Acute; Alteplase; Animals; Binding; Blood; Blood - brain barrier anatomy; Blood Vessels; Brain; Brain hemorrhage; Carotid Arteries; Cause of Death; Cerebrovascular Circulation; Characteristics; Clinical; Coagulation Process; Cytolysis; Data; Development; Dose; Edema; Elderly; Encapsulated; Environment; Event; Extravasation; FDA approved; Fibrinolytic Agents; Formulation; Goals; Half-Life; Hemorrhage; In Vitro; Infarction; Inflammation; Inflammatory; Injections; Intravenous; Ischemia; Ischemic Stroke; Kidney; Lung; Mediating; Mediator of activation protein; Memory; Mitochondria; Modeling; Morbidity - disease rate; Motor; Movement; Nanoconjugate; Natural regeneration; Neurologic; Neurons; Organ; Oxidative Stress; Phase; Play; Process; Rattus; Reactive Oxygen Species; Recovery; Recovery of Function; Reperfusion Injury; Reperfusion Therapy; Risk; Role; Sequential Treatment; Signal Transduction; Slice; Stroke; Superoxide Dismutase; Survival Rate; Symptoms; Tail; Temperature; Testing; Therapeutic Agents; Thromboembolism; Thrombus; Time; Translations; Veins; angiogenesis; antioxidant enzyme; base; blood-brain barrier disruption; brain repair; brain tissue; catalase; cost; design; disability; effective therapy; endovascular thrombectomy; enzyme activity; heart damage; improved; in vivo; intravenous administration; intravenous injection; ischemic injury; migration; nano; nanoparticle; neurogenesis; neurological recovery; neuron apoptosis; neuroprotection; neurotoxic; neurotoxicity; neurovascular; novel; post stroke; prevent; protective effect; repaired; response; socioeconomics; stem cells; stroke model; stroke patient; stroke therapy; thromboembolic stroke; thrombolysis

Stroke is a leading cause of death, long-term disability, and socioeconomic costs, highlighting the urgent need for more effective treatments. Intravenous administration of tissue plasminogen activator (tPA) is the only FDA-approved therapy to re-establish cerebral blood flow. But because of increased risk of hemorrhage beyond 4.5 hr post stroke, few stroke patients (<5%) benefit from t-PA. Further, t-PA disrupts the blood-brain barrier integrity (BBB) and is neurotoxic, aggravates reperfusion injury. Reactive oxygen species (ROS), generated soon after ischemia and during reperfusion and thereafter, are considered the main mediators of ischemia/ischemia reperfusion injury. To support this notion, in our previous studies, we showed that sequential treatment with t-PA first, followed by delivery of the antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) encapsulated in nanoparticles (nano-SOD/CAT), both administered via carotid artery 3 hr post ischemia in a thromboembolic rat stroke model, significantly reduced reperfusion injury than did tPA alone. This sequential treatment neutralized elevated ROS levels, inhibited vascular leakage/prevented edema formation, reduced inflammation, and protected neuronal cells from apoptosis. Most important, we found out that the sequential treatment stimulated migration of neuronal and circulating progenitor cells into the infarcted brain, whereas tPA alone inhibited that movement. Based on these promising results, we designed a novel dual-action tPA nanoconjugate – tPA conjugated to nano-SOD/CAT – to achieve neuro and vascular protection from reperfusion injury while retaining the thrombolytic effects of tPA. Our preliminary data show that the tPA nanoconjugate a) has markedly better thrombolytic effects than tPA alone (at 1/4 of the dose of tPA, the conjugate yielded the same degree of thrombolysis), b) causes no tPA-associated neurotoxicity, and c) when given via intravenous (tail vein) injection at 6 hr post stroke, effectively reduces infarct volume, resulting in improved neurological recovery over time and increased survival (~85%), significantly more so than in rats given tPA alone (~20%). We hypothesize that our tPA nanoconjugate, with its sustained neuroprotective effects from oxidative stress and significantly better thrombolytic effects than t-PA alone, could overcome the limitations of tPA alone in minimizing reperfusion injury and achieving neurological/functional recovery, even if treatment is delayed. Ou goal is to investigate and develop our tPA nanoconjugate as a safe and effective treatment for stroke. Specific aims are: AIM 1: To analyze the neuroprotective/thrombolytic effects of the tPA nanoconjugate. AIM 2: To evaluate the extent of neurological recovery and motor functions over time. AIM 3: To confirm the brain repair mechanisms following ischemic/reperfusion injury. An effective treatment could benefit more stroke patients than can be treated with tPA alone because of the extended window of treatment and reduced risk of hemorrhagic complications. Such a therapy could significantly diminish the extent of post-stroke disability.

中风是死亡，长期残疾和社会经济成本的主要原因，强调了 迫切需要更有效的治疗。组织纤溶酶原激活剂（TPA）的静脉注射IS FDA批准的唯一重新建立大脑血流的疗法。但是由于增加了 中风后4.5小时的出血，中风患者（<5％）受益于T-PA。此外，T-PA破坏了 血脑屏障完整性（BBB）是神经毒性的，会加剧再灌注损伤。活性氧 （ROS），缺血后不久和再灌注期间产生，此后被认为是主要的 缺血/缺血再灌注损伤的介体。为了支持这一概念，在我们以前的研究中，我们表明 首先用T-PA进行顺序处理，然后递送抗氧化酶，超氧化物歧化酶 （SOD）和过氧化氢酶（CAT）封装在纳米颗粒（纳米sod/cat）中，均通过颈动脉施用 血栓栓塞大鼠中风模型中的动脉3小时缺血，比以前显着降低了再灌注损伤 独自一人。这种顺序处理的中和升高的ROS水平，抑制了血管泄漏/阻止了 水肿形成，减少炎症和受保护的神经元细胞免受凋亡。最重要的是，我们 发现顺序处理刺激了神经元和循环祖细胞迁移到 梗塞的大脑，而单独使用TPA抑制了这种运动。基于这些承诺结果，我们设计了一种新型的双重动作TPA纳米偶联物 - TPA与纳米sod/cat结合使用，以在保持TPA的溶栓效果的同时，从而获得了神经和血管保护，从而获得了神经和血管保护。我们的初步数据表明，TPA纳米偶联a）比单独使用TPA（在TPA的剂量的1/4时，结合剂的1/4，溶结剂都产生相同程度的溶栓剂），b）导致TPA与神经毒性相同的神经毒性（通过在6次中施加均匀的脉络脉络），而在静脉下造成了均匀的脉络脉冲（均为静脉均匀）。体积，导致神经系统恢复的改善，生存率提高（约85％），仅在TPA的大鼠中，其恢复时间（约85％）（约20％）。我们假设我们的TPA纳米偶联物具有与单独使用T-PA相比，其持续的神经保护作用和明显更好的溶栓效应，可以克服单独的TPA在 最小化再灌注损伤并实现神经/功能恢复，即使治疗延迟。 ou 目的是调查和开发我们的TPA纳米缀合物，作为中风的安全有效治疗。具体的 目的是：目标1：分析TPA纳米轭物的神经保护性/溶栓效应。目标2：到 随着时间的推移，评估神经系统恢复和运动功能的程度。目标3：确认大脑修复 缺血/再灌注损伤后的机制。有效的治疗可以使更多中风患者受益 比单独使用TPA治疗的治疗范围扩大和降低的风险 出血并发症。这种疗法可能会大大减少中风后残疾的程度。