NEUROPROTECTIVE GROWTH FACTORS IN TRAUMATIC BRAIN INJURY

创伤性脑损伤中的神经保护生长因子

• 批准号: 6679479
• 负责人: TRACY K. MCINTOSH
• 金额: $ 31.7万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-12-01 至 2005-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6679479
• 关键词: acute disease /disorder; apoptosis; biological signal transduction; biotechnology; biotherapeutic agent; brain disorder chemotherapy; brain injury; chronic brain damage; cognition; disease /disorder prevention /control; disease /therapy duration; fibroblast growth factor; growth factor; immunocytochemistry; laboratory rat; laser capture microdissection; mitogen activated protein kinase; molecular pathology; nerve growth factors; neural degeneration; neural plasticity; neuromuscular system; neuroprotectants; nonhuman therapy evaluation; sensorimotor system; serial analysis of gene expression

DESCRIPTION: (Verbatim from the Applicant's Abstract) The mechanism(s) of delayed secondary injury following traumatic brain injury (TBI) may involve the alteration of specific intracellular signaling pathways involving the mitogen activated protein (MAP) kinases JNK and Erk 1/2, as well as long-term genomic changes. These pathogenic molecular events provide targets for treatment with growth factors intended to prevent or limit neurologic disability. The investigators, among others, have generated preliminary data suggesting that acute (24 hr postinjury) administration of exogenous NGF or basic fibroblast growth factor (bFGF) may be neuroprotective in experimental models of brain injury. Specific Aim 1 will assess whether administration of either NGF or bFGF in the acute post-traumatic period (beginning 24 hr postinjury) will attenuate long-term neurologic disability and neurodegenerative (apoptotic/necrotic) cell loss following experimental lateral fluid percussion (FP) brain injury in rats. The investigators will selectively infuse these growth factors directly into the injured brain over a 2-week postinjury period, and behaviorally evaluate the animals over a chronic 3-month postinjury period for neurologic motor and sensorimotor dysfunction, cognitive deficits, and regional cell death. Specific Aim 2 will evaluate the temporal and regional alterations in specific MAP kinase (JNK/Erk 1/2) signaling pathways following experimental FP brain injury, and relate the neuroprotective effects of therapy with NGF or bFGF to a reversal of the pathologic changes in JNK/Erk induced by trauma. They will use Western blotting and immunohistochemistry to support their pilot data that TBI results in activation of the pro-death kinase JNK signaling pathway and a concomitant decrease in signaling through the pro-survival Erk 1/2 pathway. The effects of NGF or bFGF therapy and cessation of 2-week therapy (i.e., growth factor withdrawal) on these trauma-induced signal transduction cascades will then be regionally and temporally evaluated. In Specific Aim 3, they will quantify the effects of NGF or bFGF therapy on trauma-induced alterations in expression profiles of genes involved in cell death/survival and long-term plasticity/remodeling of the injured CNS. The investigators will use laser capture microdissection and reverse-Northern hybridization techniques with custom-designed slot-blots to quantify expression levels of a selected panel of genes, including cell death/survival genes, cytoskeletal genes, growth-related proteins, and cytokines. Genomic changes will be confirmed at a translational level with immunohistochemistry for selected proteins. In Specific Aim 4, the investigators will selectively infuse NGF or bFGF into the injured brain over a 2-week treatment period beginning 2 weeks or 1 month postinjury and evaluate the ability of these delayed treatment paradigms to improve long-term neurological motor and cognitive function (up to 3 months postinjury) and attenuate progressive post-traumatic cell death.

描述：（逐字摘自申请人摘要） 创伤性脑损伤（TBI）后的迟发性继发性损伤可能涉及 涉及丝裂原的特定细胞内信号传导途径的改变 活化蛋白 (MAP) 激酶 JNK 和 Erk 1/2，以及长期基因组 变化。这些致病分子事件为治疗提供了靶点 旨在预防或限制神经功能障碍的生长因子。这 除其他外，调查人员已生成初步数据表明 急性（受伤后 24 小时）给予外源性 NGF 或碱性成纤维细胞 生长因子（bFGF）可能在大脑实验模型中具有神经保护作用 受伤。具体目标 1 将评估是否施用 NGF 或 bFGF 在急性创伤后时期（受伤后 24 小时开始）会减弱 长期神经功能障碍和神经退行性（凋亡/坏死）细胞 大鼠实验性侧向液体冲击（FP）脑损伤后的损失。 研究人员将有选择地将这些生长因子直接注入 在受伤后两周内对受伤的大脑进行评估，并进行行为评估 动物在慢性损伤后 3 个月内的神经运动和 感觉运动功能障碍、认​​知缺陷和区域细胞死亡。具体的 目标 2 将评估特定 MAP 的时间和区域变化 实验性 FP 脑损伤后激酶 (JNK/Erk 1/2) 信号通路， 并将 NGF 或 bFGF 治疗的神经保护作用与 逆转创伤引起的 JNK/Erk 病理变化。他们会使用 蛋白质印迹和免疫组织化学支持 TBI 的试验数据 导致促死亡激酶 JNK 信号通路的激活和 通过促生存 Erk 1/2 途径的信号传导随之减少。这 NGF 或 bFGF 治疗的影响以及停止 2 周治疗（即生长 这些创伤引起的信号转导级联的因子撤回将 然后进行区域和时间评估。在具体目标 3 中，他们将 量化 NGF 或 bFGF 治疗对创伤引起的变化的影响 参与细胞死亡/存活和长期的基因表达谱 受伤的中枢神经系统的可塑性/重塑。研究人员将使用激光 捕获显微切割和反向Northern杂交技术 定制设计的槽印迹来量化选定面板的表达水平 基因，包括细胞死亡/存活基因、细胞骨架基因、生长相关基因 蛋白质和细胞因子。基因组变化将在转化中得到证实 选定蛋白质的免疫组织化学水平。在具体目标 4 中， 研究人员将在一段时间内选择性地将 NGF 或 bFGF 注入受伤的大脑中 受伤后 2 周或 1 个月开始的 2 周治疗期并进行评估 这些延迟治疗范式改善长期的能力 神经运动和认知功能（受伤后 3 个月内）以及 减轻进行性创伤后细胞死亡。