Peroxynitrite is a Molecular Determinant of Impaired Microvascular Energetics in Alzheimer's Disease

过氧亚硝酸盐是阿尔茨海默氏病微血管能量受损的分子决定因素

• 批准号: 10307476
• 负责人: Prasad V Katakam
• 金额: $ 63.84万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10307476
• 关键词: Age; Age-Months; Aging; Alzheimer' s Disease; Alzheimer' s disease model; Animals; Antioxidants; Behavioral; Biochemical; Bioenergetics; Biological Assay; Brain; C57BL/6 Mouse; Cells; Citric Acid Cycle; Dependence; Diabetes Mellitus; Discrimination; Electron Spin Resonance Spectroscopy; Estrogens; Female; Free Radicals; Genus Hippocampus; Glycolysis; Hormones; Human; Impaired cognition; Impairment; Insulin; Knock-in; Measures; Mediating; Metabolic; Methods; Microscopy; Microvascular Dysfunction; Mitochondria; Molecular; Mus; Neurodegenerative Disorders; Nitric Oxide; Obesity; Oxidative Phosphorylation; Perceptual learning; Peroxonitrite; Physiological; Pilot Projects; Play; Porphyrins; Production; Protons; Reactive Oxygen Species; Reporting; Research; Respiration; Respiratory physiology; Risk; Role; Severities; Sex Differences; Signal Transduction; Stress; Testing; Texture; Vibrissae; age related; aged; awake; base; cerebral microvasculature; cerebrovascular; cognitive function; enzyme activity; extracellular; high throughput screening; in vivo; ischemic injury; male; molecular targeted therapies; mouse model; neglect; neurovascular coupling; neurovascular unit; novel; protein expression; response; senescence; sensor; sex; therapeutic target; two photon microscopy; two-photon

Summary Brain microvessels (BMVs) play an important role in the neurovascular coupling (NVC). Mitochondria are energy sensors of cells and impaired mitochondrial respiratory function initiate critical signaling detrimental to NVC leading to impaired cognitive function associated with Alzheimer's disease (AD). Our recent technological breakthrough utilizing Agilent Seahorse XFe extracellular flux analyzer developed a mitochondrial respiration assay in BMVs. Using this novel method, we observed age-dependent impairment of mitochondrial respiration and bioenergetics in BMVs from male and female C57Bl/6 mice. Notably, we found that BMVs from APP NL-G-F Knock-in model of AD display impaired mitochondrial respiration and accelerated senescence. Furthermore, we observed that young and aged female mice display sex-dependent differences in microvascular energetics related to the relative contribution of oxidative phosphorylation and glycolysis to overall energy production. Finally, we found that peroxynitrite scavenger (FeTMPyP) treatment enhanced non-mitochondrial respiration young female mice but enhanced proton leak in young male mice indicating that the differential peroxynitrite activity is sex-dependent. Therefore, we hypothesize that peroxynitrite differentially regulates microvascular mitochondrial function sex-dependently and is the molecular determinant of exaggerated age-related impairment of NVC and cognitive function in AD. We will employ male and female AD and C57Bl/6 mice of 8 months and 20 months age. Aim 1 will determine the sex dependent differential impact of peroxynitrite on the bioenergetics and enzyme activities (Krebs cycle, glycolysis, and antioxidants) in BMVs ex vivo. Aim 2 will determine the sex dependent differential impact of peroxynitrite on in vivo NVC responses to whisker deflections by two-photon excitation microscopy in awake mice. Aim 3 will determine the sex dependent differential impact of FeTMPyP on cognitive function by assessing whisker-dependent perceptual learning using the novel texture discrimination task. The results of this proposal would challenge the existing dogma and will demonstrate the sex-specific physiological role of peroxynitrite in regulating the microvascular bioenergetics and neurovascular unit. Furthermore, our results will firmly establish microvascular peroxynitrite as a potential therapeutic target in sex- dependent vulnerability and severity of AD and other neurodegenerative diseases.

概括 脑微血管（BMV）在神经血管耦合（NVC）中起重要作用。线粒体是能量 细胞的传感器和线粒体呼吸功能受损会引发关键信号传导对NVC有害 导致与阿尔茨海默氏病（AD）相关的认知功能受损。我们最近的技术 利用Agilent Seahorse XFE细胞外通量分析仪的突破开发了线粒体呼吸 在BMV中进行测定。使用这种新方法，我们观察到了线粒体呼吸的年龄依赖性损害 来自男性和雌性C57BL/6小鼠的BMV中的生物能学。值得注意的是，我们发现App NL-G-F的BMVS AD敲入模型显示的线粒体呼吸和加速衰老受损。此外，我们 观察到年轻的和老年的雌性小鼠在微血管能量学上表现出性别依赖性差异 与氧化磷酸化和糖酵解对总体能量产生的相对贡献有关。 最后，我们发现过氧亚硝酸盐清除剂（FETMPYP）治疗增强了非单位呼吸 年轻的雌性小鼠，但在年轻雄性小鼠的质子泄漏增强 活动是性别依赖性的。因此，我们假设过氧亚硝酸盐差异调节微血管 线粒体功能性依赖性依赖性，是夸张的年龄相关障碍的分子决定因素 AD中的NVC和认知功能。我们将使用8个月和20个的男性和女性AD和C57BL/6小鼠 几个月。 AIM 1将确定过氧亚硝酸盐对生物能学的性别差异影响和 BMVS ex Vivo中的酶活性（克雷布斯循环，糖酵解和抗氧化剂）。 AIM 2将决定性别 过氧亚硝酸盐对体内NVC对晶须偏转的依赖性差异影响 清醒小鼠的激发显微镜。 AIM 3将确定FETM型对性别因素的影响 通过使用新颖的纹理歧视评估晶须依赖性感知学习来认知功能 任务。该提案的结果将挑战现有的教条，并展示特定于性别的教条 过氧亚硝酸盐在调节微血管生物能学和神经血管单元中的生理作用。 此外，我们的结果将牢固地建立微血管过氧亚硝酸盐，作为性别的潜在治疗靶标 AD和其他神经退行性疾病的依赖脆弱性和严重性。