Hypocretin/orexin modulation of cognitive correlates of brain aging

下丘脑分泌素/食欲素对大脑衰老认知相关性的调节

基本信息

批准号：
10445459
负责人：
JIM R FADEL
金额：
$ 110.09万
依托单位：
UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-15 至 2025-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10445459
关键词：
Acetylcholine Acute Age Age-associated memory impairment Aging Alzheimer&apos s Disease Alzheimer&apos s disease related dementia Alzheimer&apos s disease risk Animals Attention Behavioral Cells Chronic Cognition Cognitive Dementia Disease Eating Exposure to Functional disorder Gene Transfer Hippocampus (Brain)Hypothalamic structure Impaired cognition Impairment Inflammatory Intervention Intranasal Administration Lead Learning Lewy Body Dementia Lewy Body Disease Link Lipopolysaccharides Long-Term Effects Longevity Maintenance Mediating Memory Microglia Morphology Narcolepsy Nerve Degeneration Neurobehavioral Manifestations Neurons Neuropeptides Neurotransmitters Pathology Peptides Performance Peripheral Pharmacology Physiological Play Process Rattus Regulation Rodent Model Role Signal Transduction Sleep Wake Cycle Source Stimulus System Testing Therapeutic Vascular Dementia Virus Work age related aged aging brain analog basal forebrain basal forebrain cholinergic neurons cholinergic cholinergic neuron cognitive function cognitive performance cytokine executive function experimental study gene therapy hypocretin knock-down middle age nerve supply neurochemistry neurocognitive disorder neuroinflammation neurotransmission novel preservation prevent response restoration sustained attention targeted treatment transmission process

项目摘要

The primary neurotransmitter hallmark of Alzheimer’s Disease (AD) is a loss of acetylcholine, produced by neurons of the basal forebrain cholinergic system (BFCS). Cholinergic cell loss or dysfunction is also a prominent component of Lewy Body Dementia and vascular dementia, respectively. Thus the BFCS contributes to several aspects of cognitive function that are negatively impacted in AD and related dementias, including attention, learning and memory. Regulation of the BFCS by afferent inputs, including those from the hypothalamus, is important for integration of homeostatic and cognitive functions. Because homeostatic and physiological disturbances, such as altered food intake or sleep-wake cycles, often precede and predict cognitive decline in AD, understanding these interactions may lead to novel points of intervention to treat or delay cognitive decline in conditions such as AD. An important source of this afferent regulation is the hypothalamic orexin/hypocretin neuropeptide system, which activates cholinergic neurons in response to stimuli that signal physiological valence. We have previously shown that aging, the strongest risk factor for AD, is associated with reduced orexin expression. Recently, orexin transmission has been shown to play a role in limiting neuroinflammation, suggesting that a diminished orexin system in aging may promote neuroinflammatory processes that further negatively impact cholinergic-dependent signaling and cognition. In this renewal application, we will dissect the mechanisms underlying the association between loss of orexin signaling, neuroinflammation and subsequent cholinergic dysfunction and neurodegeneration in an aged rodent model using virus-mediated gene transfer, neurochemical, pharmacological and cognitive behavioral approaches. We will further test the hypothesis that chronic restoration and maintenance of orexin function beginning in early aging will preserve the integrity of the BFCS by modulating local microglial dynamics. The proposed studies will begin to delineate the mechanisms by which age-related loss of orexin signaling drives cholinergic dysfunction and cognitive decline and suggest the potential for orexin-targeted therapies in preventing or ameliorating AD or related dementias, all of which are characterized by neuroinflammation and cholinergic dysfunction.

阿尔茨海默氏病（AD）的主要神经递质标志是乙酰胆碱的丧失，由基本前脑胆碱能系统（BFC）的神经元产生。胆碱能细胞丧失或功能障碍也是路易体痴呆和血管痴呆的重要组成部分。 BFC促进了认知功能的几个方面，这些方面在AD和相关痴呆症中受到负面影响，包括注意力，学习和记忆。通过传入输入（包括下丘脑的传统输入）对BFC进行调节对于整合体内稳态和认知功能很重要。由于稳态和身体疾病（例如食物摄入量改变或睡眠效果周期）通常是在AD之前和预测认知能力下降的，因此了解这些相互作用可能会导致新的干预点以治疗或延迟AD等状况的认知能力下降。这种传入调节的重要来源是下丘脑OREXIN/降孔蛋白神经肽系统，该系统激活胆碱能神经元，以响应信号生理价的刺激。我们先前已经表明，衰老是AD的强风险因素，与降低的Orexin表达有关。最近，已经证明Orexin传播在限制神经炎症中发挥作用，这表明衰老中的Orexin System降低可能会促进神经炎症过程，从而进一步对胆碱能依赖性信号传导和认知产生负面影响。在这种续签应用中，我们将使用病毒介导的基因转移，神经化学，药物和认知行为方法来剖析奥毛蛋白信号传导，神经炎症和随后的胆碱能功能障碍和随后的胆碱能功能障碍与神经变性之间关联的机制。我们将进一步检验以下假设：慢性恢复和维持在早期衰老开始的Orexin功能将通过调节局部小胶质细胞动力学来保留BFC的完整性。拟议的研究将开始描述与年龄相关的Orexin信号传导损失导致胆碱能功能障碍和认知能力下降的机制，并提出了预防或改善AD或相关痴呆症的潜力，这些疗法具有神经毒素流经症和胆红素的特征。