Molecular therapies to enhance brain recovery after experimental stroke

分子疗法促进实验性中风后大脑恢复

• 批准号: 8004760
• 负责人: Jun Chen
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-01 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8004760
• 关键词: Acute; Adult; Age; Animals; Area; Blood Vessels; Brain; Brain Injuries; Caenorhabditis elegans; Caring; Cell Death Inhibition; Cell Proliferation; Cerebral Ischemia; Cerebrum; Clinical; Data; Dependovirus; Diet; Docosahexaenoic Acids; Emergency Medicine; Enzymes; Epidemiologic Studies; Exhibits; Fatty acid glycerol esters; Gene Expression; Generations; Genes; Goals; Infarction; Inflammation; Injury; Intake; Investigation; Ischemia; Ischemic Brain Injury; Ischemic Stroke; Lead; Long-Term Effects; Medical; Methods; Middle Cerebral Artery Occlusion; Military Personnel; Mission; Molecular; Mus; N-3 polyunsaturated fatty acid; Natural regeneration; Neurologic; Neurological outcome; Neurons; Omega-3 Fatty Acids; Patient Care; Performance; Phase; Population; Production; Proteins; Quality of life; Recovery; Resistance; Risk; Stroke; Stroke prevention; Supplementation; Survivors; Testing; Therapeutic; Transgenic Mice; Transgenic Organisms; United States; Veterans; Work; aged; angiogenesis; brain repair; brain tissue; disability; effective therapy; functional outcomes; improved; migration; neovascularization; nerve stem cell; neurogenesis; neurological recovery; neuron loss; neuronal replacement; novel; post stroke; prophylactic; protective effect; repaired; restoration; stroke rehabilitation; success; white matter injury; young adult; Acute; Adult; Age; Animals; Area; Blood Vessels; Brain; Brain Injuries; Caenorhabditis elegans; Caring; Cell Death Inhibition; Cell Proliferation; Cerebral Ischemia; Cerebrum; Clinical; Data; Dependovirus; Diet; Docosahexaenoic Acids; Emergency Medicine; Enzymes; Epidemiologic Studies; Exhibits; Fatty acid glycerol esters; Gene Expression; Generations; Genes; Goals; Infarction; Inflammation; Injury; Intake; Investigation; Ischemia; Ischemic Brain Injury; Ischemic Stroke; Lead; Long-Term Effects; Medical; Methods; Middle Cerebral Artery Occlusion; Military Personnel; Mission; Molecular; Mus; N-3 polyunsaturated fatty acid; Natural regeneration; Neurologic; Neurological outcome; Neurons; Omega-3 Fatty Acids; Patient Care; Performance; Phase; Population; Production; Proteins; Quality of life; Recovery; Resistance; Risk; Stroke; Stroke prevention; Supplementation; Survivors; Testing; Therapeutic; Transgenic Mice; Transgenic Organisms; United States; Veterans; Work; aged; angiogenesis; brain repair; brain tissue; disability; effective therapy; functional outcomes; improved; migration; neovascularization; nerve stem cell; neurogenesis; neurological recovery; neuron loss; neuronal replacement; novel; post stroke; prophylactic; protective effect; repaired; restoration; stroke rehabilitation; success; white matter injury; young adult

DESCRIPTION (provided by applicant): ABSTRACT Stroke is one of the major medical concerns for United States military veterans. Stroke is devastating as currently no therapy is available to prevent stroke-induced neurological deficit. Prophylactic or therapeutic supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) has recently emerged as a highly promising neuroprotective strategy for stroke. Epidemiological studies have shown an inverse association between n-3 PUFAs intake and risk of ischemic stroke. Supplementation with n-3 PUFAs, especially DHA, effectively reduces the extent of brain damage and neurological deficits in the acute phase of ischemic injury in experimental animals. However, the long-term effect of n-3 PUFAs on brain damage and post- stroke neurological recovery is unknown. We have recently created transgenic (Tg) mice over-expressing the C elegans fat-1 gene encoding an enzyme that converts endogenous n-6 to n-3 PUFAs. Our preliminary studies with fat-1 Tg mice have suggested two-phase (acute and delayed) beneficial effects of n-3 PUFAs on ischemic stroke. The fat-1 Tg mice at either young (3-month-old) or old age (15-month-old) were remarkably resistant to focal ischemic injury compared to their age-matched wild-type (Wt) littermates, showing reduced infarct size and improved neurological functional performance up to 14 days after middle cerebral artery occlusion. We have found that angiogenesis and neurogenesis were robustly enhanced after ischemia in 3-month old fat-1 Tg mice compared to Wt littermates, suggesting that n-3 PUFAs promote post-stroke neurovascular regeneration. Strikingly, we found that post-stroke angiogenesis and neurogenesis were profoundly impaired in aged mice, but almost fully restored by transgenic expression of fat-1. This proposal attempts to further explore the long-term protective effect of n-3 PUFAs on focal cerebral ischemia. The goal is to develop n-3 PUFA supplementation as a novel, clinically feasible prophylactic and/or therapeutic strategy to promote long-term neurological recovery after stroke through stimulating the generation of functional blood vessels and new neurons. The central hypothesis to be tested in the current proposal is that prophylactic or therapeutic n-3 PUFA treatment improves long-term neurological outcomes after stroke by stimulating and enhancing post-ischemia brain repair, including augmented neurogenesis and angiogenesis. The following specific objectives are proposed: Aim 1. Test the hypothesis that n-3 PUFAs reduce long-term neurological deficits as well as brain tissue damage after focal cerebral ischemia in both young adult and aged mice. Two clinically applicable methods: 1) dietary delivery; and 2) augmented endogenous production of n-3 PUFAs via adeno-associated virus (AAV)-directed fat-1 gene expression, will be established to elevate brain levels of n-3 PUFAs. The effect of elevated n-3 PUFAs on ischemic brain injury induced by MCAO will be quantitatively evaluated. The endpoints of assessment include functional outcomes, infarct size, and white matter injury. Aim 2. Test the hypothesis that n-3 PUFA treatment enhances cerebral neurovascular regeneration, including augmented angiogenesis and neurogenesis after cerebral ischemia in both young adult and aged mice. The proposed studies will quantitatively determine the effect of n-3 PUFAs on post-stroke neovascularization and on neural stem cell proliferation, migration, differentiation and neuronal replacement following ischemic stroke. PUBLIC HEALTH RELEVANCE: NARRATIVE Stroke is one of the major medical concerns for United States military veterans. Stroke is devastating as currently no therapy is available to prevent stroke-induced neurological deficit. Prophylactic or therapeutic supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) has recently emerged as a highly promising neuroprotective strategy for stroke. Supplementation with n-3 PUFAs, especially DHA, effectively reduces the extent of brain damage and neurological deficits in the acute phase of ischemic injury in experimental animals. However, the long-term effect of n-3 PUFAs on brain damage and post-stroke neurological recovery is unknown. Our preliminary studies have suggested two-phase (acute and delayed) beneficial effects of n-3 PUFAs on ischemic stroke. We have found evidence that n-3 PUFAs promote post-stroke neurovascular regeneration. Thus, the objective of the current proposal is to develop n-3 PUFA supplementation as a novel, clinically feasible prophylactic and/or therapeutic strategy to promote long-term neurological recovery after stroke. First, we will test the hypothesis that n-3 PUFAs reduce long-term neurological deficits as well as brain tissue damage after focal cerebral ischemia in both young adult and aged mice. Second, we will test the hypothesis that n-3 PUFA treatment enhances cerebral neurovascular regeneration.

描述（由申请人提供）： 抽象中风是美国退伍军人的主要医疗问题之一。中风是毁灭性的，因为目前尚无治疗可预防中风引起的神经系统缺陷。用omega-3多不饱和脂肪酸（N-3 PUFAS）进行预防或治疗性补充，最近已成为一种高度有希望的中风神经保护策略。流行病学研究表明，N-3 PUFAS摄入量与缺血性中风风险之间存在反向关联。补充N-3 PUFA，尤其是DHA，有效地减少了实验动物缺血性损伤急性期脑损伤和神经缺陷的程度。但是，N-3 PUFAS对脑损伤和中风后神经恢复的长期影响尚不清楚。最近，我们创建了过表达C秀丽隐杆线虫脂肪1基因的转基因（TG）小鼠，该酶编码将内源性N-6转换为N-3 PUFAS的酶。我们对脂肪1 TG小鼠的初步研究表明N-3 PUFAS对缺血性中风的两相（急性和延迟）有益作用。与年龄匹配的野生型（WT）同窝仔相比，年轻（3个月大）或老年（15个月大）处于年轻人（3个月大）或老年（15个月大）的脂肪1 TG小鼠具有明显的抵抗力，显示出梗塞的大小和脑膜功能降低，在中脑脑脑闭塞后至14天提高了神经功能性能。我们发现，与WT同窝仔相比，在3个月旧的脂肪1 TG小鼠缺血后，血管生成和神经发生在缺血后得到了强劲增强，这表明N-3 PUFA促进了势后神经血管内再生。引人注目的是，我们发现卒中后血管生成和神经发生在老年小鼠中受到了严重损害，但几乎通过FAT-1的转基因表达完全恢复了。该建议试图进一步探索N-3 PUFAS对局灶性脑缺血的长期保护作用。目的是开发N-3 PUFA作为一种新颖的，临床上可行的预防性和/或治疗策略，以促进中风后长期神经恢复，通过刺激功能性血管和新神经元的产生。当前建议中要检验的中心假设是，预防性或治疗性N-3 PUFA治疗通过刺激和增强异化后脑修复（包括增强的神经发生和血管生成）来改善中风后的长期神经学结局。提出了以下特定目标：目标1。检验以下假设：N-3 PUFA可减少长期神经缺陷以及局灶性大脑缺血后年轻小鼠和老年小鼠后脑组织损伤。两种临床上适用的方法：1）饮食分娩； 2）将通过腺相关病毒（AAV）指导的脂肪-1基因表达增强内源性的N-3 PUFA，以升高N-3 PUFAS的大脑水平。将对N-3 PUFAS升高对MCAO引起的缺血性脑损伤的影响进行定量评估。评估的终点包括功能结果，梗塞大小和白质损伤。 AIM 2。检验以下假设：N-3 PUFA治疗增强了脑神经血管再生，包括在年轻成年和老年小鼠中脑缺血后的增强血管生成和神经发生。拟议的研究将定量确定N-3 PUFA对势后新血管形成以及缺血性中风后神经干细胞增殖，迁移，分化和神经元替代的影响。 公共卫生相关性： 叙事中风是美国退伍军人的主要医疗问题之一。中风是毁灭性的，因为目前尚无治疗可预防中风引起的神经系统缺陷。用omega-3多不饱和脂肪酸（N-3 PUFAS）进行预防或治疗性补充，最近已成为一种高度有希望的中风神经保护策略。补充N-3 PUFA，尤其是DHA，有效地减少了实验动物缺血性损伤急性期脑损伤和神经缺陷的程度。但是，N-3 PUFAS对脑损伤和中风后神经系统康复的长期影响尚不清楚。我们的初步研究表明N-3 PUFAS对缺血性中风的两相（急性和延迟）有益作用。我们发现了N-3 PUFA促进了中风后神经血管再生的证据。因此，当前建议的目的是将补充N-3 PUFA作为一种新颖的临床可行的预防性和/或治疗策略，以促进中风后的长期神经恢复。首先，我们将检验以下假设：N-3 PUFA减少了年轻小鼠和老年小鼠局灶性脑缺血后的长期神经缺陷以及脑组织损伤。其次，我们将测试N-3 PUFA治疗增强脑神经血管再生的假设。