The NADPH oxidase enzyme as a therapeutic target after Spinal Cord Injury

NADPH 氧化酶作为脊髓损伤后的治疗靶点

• 批准号: 8416963
• 负责人: Kimberly Byrnes
• 金额: $ 25.35万
• 依托单位: HENRY M. JACKSON FDN FOR THE ADV MIL/MED
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8416963
• 关键词: Acute; Affect; Anti-Inflammatory Agents; Anti-inflammatory; Bladder; Cell Death; Chronic; Data; Diffusion Magnetic Resonance Imaging; Enzyme Inhibition; Enzyme Inhibitor Drugs; Enzyme Inhibitors; Enzymes; Evolution; Family; Genetic; Goals; Hindlimb; Hour; Immunohistochemistry; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Injury; Knock-out; Label; Lesion; Life; Macrophage Activation; Magnetic Resonance Imaging; Measures; Mechanics; Microglia; Molecular Profiling; Motor; NADPH Oxidase; Pattern; Peptides; Phenotype; Play; Production; Protein Isoforms; Rattus; Reactive Oxygen Species; Recovery; Recovery of Function; Reporting; Role; Secondary to; Sensory; Site; Source; Spinal Cord; Spinal cord injury; Testing; Therapeutic; Time; Tissues; Toxic effect; United States; Up-Regulation; Wild Type Mouse; axonal sprouting; clinically relevant; disability; enzyme activity; functional loss; improved; inflammatory marker; inhibitor/antagonist; insight; macrophage; neurotoxicity; research study; therapeutic target

DESCRIPTION (provided by applicant): Over 250,000 people in the United States are currently living with disabilities caused by spinal cord injury (SCI), and approximately 12,000 new injuries are reported each year. Inflammation, including activation of microglia and invasion of macrophages, plays a central role in the secondary injury observed after SCI. After SCI, the NOX family of enzymes is chronically up-regulated and may contribute to microglial/macrophage activation, inflammation and tissue damage through the production of reactive oxygen species (ROS). This expression profile coincides with the invasion of macrophages and activation of microglia into a pro-inflammatory, or M1, phenotype, but not with the M2, or anti-inflammatory, phenotype. Knockout of the NOX2 isoform can reduce ROS production. Further, acute pharmacological inhibition of NOX2 reduces lesion volume following SCI in rats. However, the expression profile of the family of enzymes is currently unclear and the effect of NOX2 inhibition on chronic inflammation, axonal sparing, or motor or autonomic function after SCI is unknown. Therefore, we hypothesize that NOX2 is the primary NOX isoform expressed in M1 microglia/macrophages after spinal cord injury and that inhibition of NOX2 will reduce chronic inflammation and improve recovery, including axonal sprouting/sparing and motor and autonomic function. To test this hypothesis, we propose three specific aims. In aim 1, we will identify the NOX isoform expression profile and correlation with M1 and M2 phenotype after spinal cord injury. In this aim, we will use immunohistochemistry to identify the expression profile of the NOX isoforms and their co-localization with M1 and M2 activation markers. In aim 2, we will demonstrate that NOX2 inhibition induces an M2 phenotype in microglia and macrophages and reduces inflammation in the injured spinal cord. In this aim, we will assess inflammation after moderate SCI at acute, sub-acute and chronic time points using both genetic knockout (gp91PHOX) and pharmacological inhibition approaches. Finally, in aim 3 we will show that delayed administration of a NOX2 inhibitor improves axonal sprouting and sparing and restores motor and autonomic function after spinal cord injury. Utilizing a NOX2 specific inhibitor, we will assess motor and autonomic function, as well as axonal sparing and sprouting. The proposed research study will clarify the role of NOX after SCI and demonstrate the therapeutic applications of NOX inhibition. The data from these studies will provide insight into the role of inflammation, including chronic inflammation, in recovery from SCI.

描述（由申请人提供）：目前美国有超过 250,000 人因脊髓损伤 (SCI) 导致残疾，每年报告约 12,000 例新损伤。炎症，包括小胶质细胞的激活和巨噬细胞的侵袭，在 SCI 后观察到的继发性损伤中起着核心作用。 SCI 后，NOX 酶家族长期上调，可能通过产生活性氧 (ROS) 导致小胶质细胞/巨噬细胞激活、炎症和组织损伤。这种表达谱与巨噬细胞的侵袭和小胶质细胞活化成促炎表型或 M1 表型一致，但与 M2 表型或抗炎表型不相符。 NOX2 同工型的敲除可以减少 ROS 的产生。此外，NOX2 的急性药理学抑制可减少大鼠 SCI 后的病变体积。然而，该酶家族的表达谱目前尚不清楚，并且 NOX2 抑制对 SCI 后慢性炎症、轴突保留或运动或自主功能的影响尚不清楚。因此，我们假设 NOX2 是脊髓损伤后 M1 小胶质细胞/巨噬细胞中表达的主要 NOX 亚型，抑制 NOX2 将减少慢性炎症并改善恢复，包括轴突萌芽/保留以及运动和自主功能。为了检验这一假设，我们提出了三个具体目标。在目标 1 中，我们将确定脊髓损伤后 NOX 亚型表达谱及其与 M1 和 M2 表型的相关性。为此，我们将使用免疫组织化学来鉴定 NOX 亚型的表达谱及其与 M1 和 M2 激活标记的共定位。在目标 2 中，我们将证明 NOX2 抑制会诱导小胶质细胞和巨噬细胞出现 M2 表型，并减少受损脊髓的炎症。为此，我们将使用基因敲除 (gp91PHOX) 和药物抑制方法评估中度 SCI 后急性、亚急性和慢性时间点的炎症。最后，在目标 3 中，我们将证明延迟施用 NOX2 抑制剂可改善轴突萌芽和保留，并恢复脊髓损伤后的运动和自主功能。利用 NOX2 特异性抑制剂，我们将评估运动和自主神经功能，以及轴突保留和发芽。拟议的研究将阐明 SCI 后 NOX 的作用，并证明 NOX 抑制的治疗应用。这些研究的数据将深入了解炎症（包括慢性炎症）在 SCI 恢复中的作用。