New Therapies to Restore Vascular Integrity During Sepsis

脓毒症期间恢复血管完整性的新疗法

基本信息

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
项目类别：
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

项目摘要

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.

项目概要/摘要脓毒症是宿主对感染的灾难性全身炎症反应，可导致血管渗漏，尽管进行了大量研究，但除了非特异性外，很少有治疗策略。支持性护理已得到发展，感染性休克病例的死亡率仍高达 60-70%。每年有超过 750,000 名美国人感染败血症，其中死亡人数比死于败血症的人数还要多已知在败血症中发现的激动剂会导致乳腺癌、前列腺癌和艾滋病。患者，如炎症细胞因子、VEGF、凝血酶、微粒、细菌毒素和细菌它们本身会引起血管不稳定和水肿，从而有助于引发脓毒症的病理生理学。数据表明，这些内皮细胞干扰剂的直接和立即影响可能是通过多种受体通过共同的汇聚点发出信号，即细胞内 GTPase ARF6。控制细胞-细胞连接蛋白的运输，与典型的炎症途径不同调节转录（例如，在炎症性疾病动物模型中激活 NF-κB）。通过条件性基因消融或化学抑制激活 ARF6 可稳定脉管系统，减少炎症并提高存活率因此，我们帮助激活了 ARF6。脓毒症期间会引起病理性血管渗漏，导致多器官衰竭和死亡 ARF6 或其激活的 ARF-GEF 的药理抑制或基因消除将稳定人类和小鼠内皮暴露于脓毒症损伤并提高脓毒症动物模型的存活率。认识到小鼠的败血症反应可能并不完全模仿人类的反应，因此，我们将。评估物种之间在 ARF-GEF—ARF6 途径及其相关方面的异同在目标 1 中，我们将确定 ARF6 是否代表的收敛点。我们将使用定义的调节由脓毒症环境中产生的激动剂诱导的血管通透性。脓毒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旁通透性。在目标 2 中，我们将鉴定参与这些信号传导过程的 ARF-GEF 和接头蛋白。单独消除小鼠中的 Arf6 和 Arno（一种已知的 ARF6-GEF），并在几种小鼠中使用 ARF6 的化学抑制脓毒症动物模型以确定去除或抑制 ARF6 活性是否可以稳定脉管系统为了更接近地模拟临床情况，我们还将使用 ARF6 抑制作为一种方法。抗生素辅助评估联合治疗是否可以减少血管渗漏和死亡率在目标 3 中，我们检查了 ARF6 抑制在体外人类脓毒症模型中的功效。通过评估 ARF6 阻断和暴露于血浆或微粒后的内皮完整性脓毒症患者的体外全血模型也将用于评估 ARF6 功能。