Caveolin-mediated neuronal signaling in differentiated adult human neuronal stem cells and the aging brain

到2050年，65岁以上的人口将增加到约8700万。[Age是最大的风险因素， 发展为阿尔茨海默病（AD）和其他形式的神经变性，如帕金森病（PD）， 肌萎缩侧索硬化症（ALS）或抑郁症。没有预防或治疗，与年龄有关 到2050年，神经退行性疾病可能达到1100万至1600万。到2035年，今天的退伍军人将是中年人， 健康问题，如在年老的越南退伍军人中看到的，由创伤后应激障碍的并发症复杂化 创伤性脑损伤和多发性创伤。在神经退化过程中，大脑表现出区域- 神经元形态的特定改变，结构可塑性和树突分支的减少，以及 再生能力下降。大脑的功能是由电活动和化学物质支撑的。 神经元之间的通信;细胞之间的这种通信对于重建正常的 AD大脑的功能除了启动神经元生长的遗传调节外， 干预，如1）选择性5-羟色胺和多巴胺再摄取抑制（SDRI），以促进cAMP，或2） [神经营养因子受体激动]可能促进结构和功能可塑性，并改善行为， 患有AD的人。正常的神经元生长和引导依赖于来自 细胞外信号（即，空间信息）通过质膜。一个关键的质膜“枢纽”， 将细胞外信号转导至细胞骨架的基本机制是膜/脂筏（MLR）， 富含鞘脂、胆固醇和支架蛋白小窝蛋白-1（Cav-1）的离散微区。 神经元的极化和运动依赖于位于其前缘的MLR。我们先前已经 证明神经元靶向Cav-1过表达（通过将其与神经元特异性 突触蛋白启动子[SynCav 1]）：1）增强膜胆固醇、MLR形成和突触受体 表达和信号传导（TrkB）; 2）增加5-羟色胺受体（5-HT 6）和多巴胺受体介导的 (D1R)cAMP形成; 3）即使在生长的情况下也促进树枝发芽和树枝化 抑制剂的我们小组最近的一份开创性出版物表明，将SynCav 1直接递送到 脑增强成年小鼠（6个月）和老年小鼠（20个月）海马神经可塑性的结构和功能 mo），并改善成年和老年小鼠的大脑依赖性情境恐惧学习和记忆。 这些结果提供了概念验证的证据，即通过增加Cav-1在神经元中的特异性表达， 可以改善结构和功能性神经可塑性，具有积极的行为结果。本申请 试图确定SynCav 1是否可以在分化的人类神经细胞中诱导类似的神经可塑性变化， 神经元干细胞（NSC）来源于诱导多能干细胞（iPSC），然后使用SynCav 1在 与SSRIs、SDRIs或TrkB激动剂组合以显著增加行为改善率 在AD小鼠中。我们的研究将利用一种新的成人分化神经干细胞的体外模型 （NSC）衍生自诱导多能干细胞（iPSC）与量子点轴突运输时间的组合。 用于评估神经元功能的衰减成像，以及体内遗传干预、药理学和运动 治疗技术，电生理学，共聚焦和扫描电子显微镜，和电机和 认知电池完成拟议的实验可能会导致使用新的 针对Cav-1和MLR的治疗干预（小分子，肽，基因操作）， 目的是在退伍军人群体中对抗AD相关的神经变性或神经创伤。

The population over 65 will increase to ~87 million by 2050. [Age alone is the greatest risk factor for developing Alzheimer's disease (AD) and other forms of neurodegeneration such as Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) or depression.] With no prevention or treatment, aged-related neurodegeneration could reach 11-16 million by 2050. In 2035, today's Veterans will be middle-aged, with health issues like those seen in aging Vietnam Veterans, complicated by comorbidities of posttraumatic stress disorder, traumatic brain injury, and polytrauma. During neurodegeneration, the brain demonstrates region- specific alterations in neuronal morphology, reduced structural plasticity and dendritic branching, and a decreased capacity to regenerate. Brain function is underpinned by both electrical activity and chemical communication between neurons; this communication between cells is necessary for re-establishing normal brain function in the AD brain. In addition to genetic modulation that initiate neuronal growth, other interventions such as 1) selective serotonin and dopamine reuptake inhibition (SDRI) to promote cAMP, or 2) [neurotrophin receptor agonism] may promote structural and functional plasticity and improve behavior in individuals afflicted with AD. Proper neuronal growth and guidance is dependent upon communication from extracellular signals (i.e., spatial information) through the plasma membrane. A key plasmalemmal `hub' that transduces the extracellular cues to the underlying cytoskeletal machinery are membrane/lipid rafts (MLR), discrete microdomains enriched in sphingolipids, cholesterol, and scaffolding protein caveolin-1 (Cav-1). Neuronal polarization and motility is dependent upon MLR localized in its leading edge. We have previously demonstrated that neuron-targeted Cav-1 over-expression (achieved by linking it to a neuron-specific synapsin promoter [SynCav1]): 1) enhances membrane cholesterol, MLR formation, and synaptic receptor expression and signaling (TrkB); 2) increases serotonin receptor (5-HT6) and dopamine receptor-mediated (D1R) cAMP formation; 3) promotes dendritic sprouting and arborization even in the presence of growth inhibitors. A recent seminal publication from our group demonstrates that direct delivery of SynCav1 into the brain augments structural and functional hippocampal neuroplasticity in adult mice (6 mo) and aged mice (20 mo) and improves hippocampal-dependent contextual fear learning and memory in both adult and aged mice. These results provide proof-of-concept evidence that by increasing expression of Cav-1 specifically in neurons, one can improve structural and functional neuroplasticity with positive behavioral outcome. This application seeks to determine whether SynCav1 can induce similar neuroplastic changes in differentiated human neuronal stem cells (NSCs) derived from induced pluripotent stem cells (iPSCs) and then to use SynCav1 in combination with SSRIs, SDRIs, or TrkB agonism to significantly augment the rate of behavioral improvement in AD mice. Our study will utilize a novel in vitro model of adult human differentiated neuronal stem cells (NSCs) derived form induced pluripotent stem cells (iPSCs) combined with quantum dot axonal transport time- lapse imaging to assess neuronal function, and in vivo genetic interventions, pharmacological, and exercise therapeutic techniques, electrophysiology, confocal and scanning electron microscopy, and motor and cognitive batteries. Completion of the proposed experiments could lead to the justification of using novel therapeutic interventions (small molecules, peptides, gene manipulation) that target Cav-1 and MLR for the purpose of combating AD-associated neurodegeneration or nerve trauma in the Veteran population.