New Therapies to Restore Vascular Integrity During Sepsis

脓毒症期间恢复血管完整性的新疗法

• 批准号: 9277547
• 负责人: SHANNON J ODELBERG
• 金额: $ 73.35万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9277547
• 关键词: ADP-ribosylation factor 6; Ablation; Acquired Immunodeficiency Syndrome; Acute Lung Injury; Adaptor Signaling Protein; Adherens Junction; Adjuvant; Affect; Agonist; American; Animal Model; Antibiotics; Bacteria; Bacterial Toxins; Biological Models; Blood Vessels; Cell Culture Techniques; Cells; Cessation of life; Chemicals; Clinical; Clinical Trials; Combined Modality Therapy; Communicable Diseases; Contracts; Data; Death Rate; Development; Diagnosis; Disease; Disseminated Intravascular Coagulation; Edema; Endothelial Cells; Endothelium; Ensure; Excision; Exposure to; Failure; Family member; Functional disorder; Future; Genetic; Genetic Transcription; Guanine Nucleotide Exchange Factors; Guanosine Triphosphate Phosphohydrolases; Human; Immune response; In Vitro; Individual; Infection; Inflammation; Inflammatory; Inflammatory Response; Influenza; Influenza A Virus, H1N1 Subtype; Intercellular Junctions; Interleukin-1 beta; Lead; Malignant neoplasm of prostate; Mediating; Modeling; Molecular; Monomeric GTP-Binding Proteins; Mus; National Institute of General Medical Sciences; Organ failure; Pathologic; Pathway interactions; Patients; Permeability; Pharmaceutical Preparations; Pharmacology; Physiology; Plasma; Process; Proteins; RNA Interference; Receptor Signaling; Role; Sampling; Sepsis; Septic Shock; Signal Pathway; Signal Transduction; Supportive care; Survival Rate; Syndrome; TNF gene; Testing; Therapeutic; Thrombin; Vascular Endothelial Growth Factors; Vascular Permeabilities; Whole Blood; cytokine; experimental study; genetic manipulation; in vivo; inhibitor/antagonist; malignant breast neoplasm; mortality; mouse model; novel; novel therapeutics; response; septic; trafficking; treatment strategy

PROJECT SUMMARY/ABSTRACT Sepsis is a catastrophic systemic inflammatory host response to infection, which can lead to vascular leak, edema, organ failure, and death. Despite intense study, few therapeutic strategies other than nonspecific supportive care have been developed and death rates remain as high as 60-70% in cases of septic shock. More than 750,000 Americans contract sepsis each year and more of these patients die than those that succumb to breast cancer, prostate cancer, and AIDS combined. It is known that agonists found in septic patients, such as inflammatory cytokines, VEGF, thrombin, microparticles, bacterial toxins, and bacteria themselves induce the vascular instability and edema that help trigger septic pathophysiology. Our preliminary data suggest that the direct and immediate effects of these endothelial-disrupting agents may be mediated by diverse receptors that signal via a common convergence point, the intracellular GTPase ARF6. ARF6 appears to control trafficking of cell-cell junction proteins and is distinct from the canonical inflammatory pathways that regulate transcription (e.g., those activating NF-κB). In animal models of inflammatory disease, inhibiting the activation of ARF6 either through conditional genetic ablation or chemical inhibition stabilizes the vasculature, decreases inflammation, and increases survival rates. Therefore, we hypothesize that activation of ARF6 during sepsis induces pathologic vascular leak, which contributes to multi-organ failure and death and that pharmacologic inhibition or genetic ablation of ARF6 or its activating ARF-GEFs will stabilize human and mouse endothelium exposed to septic insults and increase survival rates in animal models of sepsis. We realize that the septic response in mice may not completely mimic the human response. Therefore, we will assess the similarities and differences between the species in regards to ARF-GEF—ARF6 pathway and its control of vascular integrity. In Aim 1, we will determine whether ARF6 represents a convergence point for regulating vascular permeability induced by agonists generated in the septic milieu. We will use defined agonists that are present in the plasma of sepsis patients to determine whether these agonists signal through ARF6 or other ARF family members to induce paracellular permeability of both human and mouse endothelium. We will identify the ARF-GEFs and adaptor proteins involved in these signaling processes. In Aim 2, we will individually ablate Arf6 and Arno (a known ARF6-GEF) in mice and use chemical inhibition of ARF6 in several animal models of sepsis to determine whether removal or inhibition of ARF6 activity stabilizes the vasculature and increases survival rates. To more closely mimic clinical situations, we will also use ARF6 inhibition as an adjuvant to antibiotics to assess whether combination therapy can reduce vascular leak and mortality rates in these animal models. In Aim 3, we examine the efficacy of ARF6 inhibition in in vitro human models of sepsis by assessing endothelial integrity following ARF6 blockade and exposure to plasma or microparticles from septic patients. In vitro whole blood models of sepsis will also be used to assess ARF6 function.

项目摘要/摘要 败血症是一种灾难性的全身炎症宿主对感染的反应，这可能导致血管泄漏， 尽管进行了深入研究，但除非特异性的治疗策略很少 在败血性休克病例中，已经开发了支持性护理，死亡率仍然高达60-70％。 每年超过75万美国人签约败血症，其中这些患者的死亡比 屈服于乳腺癌，前列腺癌和艾滋病。众所周知，在化粪池中发现激动剂 患者，例如炎性细胞因子，VEGF，凝血酶，微粒，细菌毒素和细菌 本身会诱导有助于触发化脓性病理生理学的血管不稳定性和水肿。我们的初步 数据表明，这些内皮干扰剂的直接和直接影响可能是由 通过公共收敛点（细胞内GTPase ARF6）发出信号的潜水受体。 ARF6出现 控制细胞 - 细胞连接蛋白的运输，并且与规范的炎症途径不同 调节转录（例如，那些激活NF-κB）。在炎症性疾病的动物模型中，抑制 通过有条件的遗传消融或化学抑制使ARF6激活稳定脉管系统， 降低影响力，并提高生存率。因此，我们假设ARF6的激活 在脓毒症期间，诱导病理血管泄漏，这有助于多器官失败和死亡，并且 ARF6或其激活ARF-GEF的药理抑制或遗传消融将稳定人类和 败血症动物模型中的小鼠内皮暴露于化粪池损伤并增加了存活率。我们 意识到小鼠的化粪池反应可能不会完全模仿人类的反应。因此，我们会的 评估该物种在ARF-GEF方面的相似性和差异-ARF6途径及其 控制血管完整性。在AIM 1中，我们将确定ARF6是否代表 调节化粪池环境中产生的激动剂引起的血管通透性。我们将使用定义的 败血症患者血浆中存在的激动剂，以确定这些激动剂是否通过 ARF6或其他ARF家族成员诱导人和小鼠内皮的细胞细胞渗透性。 我们将确定参与这些信号过程的ARF-GEF和衔接蛋白。在AIM 2中，我们将 在小鼠中单独烧蚀Arf6和Arno（已知的ARF6-GEF），并在几种中使用ARF6的化学抑制作用 败血症的动物模型，以确定去除或抑制ARF6活性是否稳定脉管系统 并提高生存率。为了更紧密地模拟临床情况，我们还将使用ARF6抑制作用作为 抗生素辅助疗法以评估联合疗法是否可以降低血管泄漏和死亡率 这些动物模型。在AIM 3中，我们检查了ARF6抑制败血症模型的效率 通过评估ARF6桶后的内皮完整性，并暴露于等离子体或微粒 化粪池患者。败血症的体外全血模型也将用于评估ARF6功能。