A Hybrid PARP Inhibitor and Redox Catalyst for Lung Transplantation

用于肺移植的混合 PARP 抑制剂和氧化还原催化剂

• 批准号: 8248350
• 负责人: Garry John Southan
• 金额: $ 24.95万
• 依托单位: RADIKAL THERAPEUTICS, INC.
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-10 至 2014-08-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8248350
• 关键词: Acute; Address; Adult Respiratory Distress Syndrome; Animal Model; Animals; Apoptosis; Attention; Attenuated; Autopsy; Biological Assay; Blinded; Blood; Blood Chemical Analysis; Breathing; Bronchoalveolar Lavage; Cells; Cessation of life; Chairperson; Chemistry; Chlorine; Clinical; Complication; Cytoprotective Agent; DNA Damage; DNA Repair Enzymes; DNA Single Strand Break; Dose; Drug Delivery Systems; Environmental air flow; Excision; Exhibits; Experimental Models; Free Radicals; Genes; Genetic; Hematology; Histologic; Histology; Histopathology; Hospitalization; Hybrids; Hydrogen Peroxide; Hydroxyl Radical; In Situ; In Vitro; Infiltration; Inflammatory; Inhibitory Concentration 50; Injury; Intercellular adhesion molecule 1; Interruption; Investigation; Ischemia; Left lung; Legal patent; Length; Life; Lipid Peroxidation; Long-Evans Rats; Lung; Lung Transplantation; Lung diseases; Macrophage Inflammatory Protein-1; Measures; Mechanical ventilation; Medical; Membrane; Modality; Modeling; Multiple Organ Failure; Mus; Necrosis; Neutrophil Infiltration; Nitrosation; Nuclear; Organ; Organ Transplantation; Orphan Drugs; Outcome; Oxidation-Reduction; Oxygen; P-Selectin; Pathway interactions; Permeability; Peroxonitrite; Pharmaceutical Preparations; Pharmacodynamics; Pharmacotherapy; Placebo Control; Plasma; Pneumonia; Poly(ADP-ribose) Polymerases; Population; Prevention; Property; Proteins; Pulmonary Edema; Randomized; Rattus; Relative (related person); Reperfusion Injury; Reperfusion Therapy; Residual state; Respiratory Failure; Resuscitation; Rodent Model; Serum; Shunt Device; Small Inducible Cytokine A3; Staging; Stress; Structure of parenchyma of lung; Sulfhydryl Compounds; Superoxides; TNF gene; Technology; Testing; Therapeutic; Tissues; Toxic effect; Toxin; Translating; Translations; Transplantation; Vascular Permeabilities; Zymosan; base; catalase; catalyst; clinically relevant; drug market; exhaustion; follow-up; graft failure; hemodynamics; in vivo; in vivo Model; indexing; inhibitor/antagonist; innovation; lung injury; lung ischemia; medical complication; mimetics; mortality; neurobehavioral; neutrophil; nitrosative stress; novel; oxidant stress; prevent; professor; prophylactic; prospective; response; small molecule; treatment effect

DESCRIPTION (provided by applicant): Radikal Therapeutics (RTX) is developing a novel bifunctional small molecule, R-503, intended for the prevention of lung ischemia-reperfusion injury (LIRI) associated with orthotopic lung transplantation. LIRI results from an acute reperfusion-induced alteration in the synthesis of the free radical superoxide anion that is subsequently converted into powerful toxins, including peroxynitrite, hydrogen peroxide, and hydroxyl radical. These oxidizing and nitrosating species induce DNA single strand breaks that activate poly(ADP-ribose) polymerase (PARP), a nuclear DNA repair enzyme that in turn depletes its substrate NAD, resulting in an exhaustion of intracellular energetics, ATP depletion, and tissue necrosis. PARP activation also induces a widespread expresion of pro-inflammatory genes that contribute to vascular permeability, lung edema, neutrophil infiltration, pulmonary shunt, and respiratory failure. In experimental models of LIRI injury, pharmacologic inhibition of PARP potently reduces lung injury, but the extent of protection was not complete and its successful clinical translation is uncertain. We now propose a more thorough interruption of LIRI-induced tissue damage, exploiting the simultaneous and synergistic removal of upstream DNA-damaging oxidizing and nitrosating species plus downstream PARP inhibition. R-503 is formed from the covalent linkage of 2 moieties, each with demonstrated tissue protection: 1) a PARP inhibitor moiety, and 2) a thiol-rich dihydrolipoyl ("DHL") domain that acts as a broad-spectrum redox catalyst. The inclusion of the DHL moiety confers unique properties on R-503, allowing the molecule to shut down both PARP-dependent and PARP-independent pathways of redox stress. R-503 is a potent PARP inhibitor (IC50=20 nM), more cytoprotective than a monofunctional PARP inhibitor in vitro, and remarkably protective in vivo, as shown in murine LD100 models of zymosan-induced multiple organ failure and chlorine inhalational lung injury. Specific Aim: Establish the superiority and in vivo synergy of the bifunctional PARP inhibitor R-503 in an experimental rat model of LIRI. Prior to 90 min of unilateral lung ischemia and 4 h of reperfusion, rats will be treated with IV R-503, DHL, a monofunctional PARP inhibitor (INO-1001), or a combination of DHL and INO-1001. A sham animal will not undergo ischemia nor receive drug therapy. We expect that R-503 will exhibit superior efficacy, relative to treatment with INO-1001, DHL, and their combination, with respect to: 1) tissue damage (histology score, levels of neutrophil infiltration, lipid peroxidation, protein nitrosation, vascular permeability, PARP activation, and apoptosis) and arterial oxygenation; and 2) bronchoalveolar lavage markers of pulmonary injury (levels of neutrophil infiltration, concentrations of TNF-¿, MIP-1¿, and nuclear NF-?B). Such treatment effects are expected to translate into clinical endpoints in LIRI of decreased: 1) pulmonary shunt, 2) duration of mechanical ventilation, 3) length of hospitalization, and 4) all-cause 30 and 365 day mortality. PUBLIC HEALTH RELEVANCE: Ischemia-reperfusion injury is a major medical complication following lung transplantation and contributes to the high mortality in this population. At present there are no approved prophylactic measures. We are developing a novel drug that targets the basic mechanisms of this condition and will test this agent in a clinically-relevant animal model.

描述（由申请人提供）：Radikal Therapeutics (RTX) 正在开发一种新型双功能小分子 R-503，旨在预防与原位肺移植相关的肺缺血再灌注损伤 (LIRI)。 LIRI 是由急性再灌注引起的自由基超氧阴离子合成变化引起的，自由基超氧阴离子随后转化为强大的毒素，包括过氧亚硝酸盐、过氧化氢和羟​​基自由基。这些氧化和亚硝化物质诱导 DNA 单链断裂，激活聚（ADP-核糖）聚合酶 (PARP)，这是一种核 DNA 修复酶，反过来会耗尽其底物 NAD，导致细胞内能量耗尽、ATP 耗尽和组织坏死。 PARP 激活还会诱导促炎基因的广泛表达，从而导致血管通透性、肺水肿、中性粒细胞浸润、肺分流和呼吸衰竭。在 LIRI 损伤的实验模型中，PARP 的药物抑制可有效减轻肺损伤，但保护程度并不完全，其成功的临床转化尚不确定。我们现在提出更彻底地中断 LIRI 诱导的组织损伤，同时协同去除上游 DNA 损伤性氧化和亚硝化物质以及下游 PARP 抑制。 R-503 由 2 个部分共价连接而成，每个部分都具有组织保护作用：1) PARP 抑制剂部分，2) 富含硫醇的二氢硫辛酰 (“DHL”) 结构域，充当广谱氧化还原催化剂。 DHL 部分的包含赋予了 R-503 独特的特性，使该分子能够关闭 PARP 依赖性和 PARP 独立的氧化还原应激途径。 R-503 是一种有效的 PARP 抑制剂 (IC50=20 nM)，在体外比单功能 PARP 抑制剂具有更强的细胞保护作用，在体内也具有显着的保护作用，如酵母聚糖诱导的多器官衰竭和氯吸入性肺损伤的小鼠 LD100 模型所示。具体目标：在 LIRI 实验大鼠模型中建立双功能 PARP 抑制剂 R-503 的优越性和体内协同作用。在单侧肺缺血 90 分钟和再灌注 4 小时之前，将用 IV R-503、DHL、单功能 PARP 抑制剂 (INO-1001) 或 DHL 和 INO-1001 的组合治疗大鼠。假动物不会发生缺血，也不会接受药物治疗。我们预计，相对于 INO-1001、DHL 及其组合治疗，R-503 将在以下方面表现出卓越的功效：1) 组织损伤（组织学评分、中性粒细胞浸润水平、脂质过氧化、蛋白质亚硝化、血管通透性、PARP 激活和细胞凋亡）和动脉氧合； 2) 肺损伤的支气管肺泡灌洗标志物（中性粒细胞浸润水平、TNF-¿、MIP-1¿ 和核 NF-κB 浓度）。这种治疗效果预计将转化为 LIRI 的临床终点：1) 肺分流，2) 机械通气持续时间，3) 住院时间，以及 4) 全因 30 和 365 天死亡率。 公共卫生相关性：缺血再灌注损伤是肺移植后的主要医疗并发症，导致该人群的高死亡率。目前尚无批准的预防措施。我们正在开发一种针对这种情况的基本机制的新药，并将在临床相关的动物模型中测试该药物。