Effects of APOE on neuronal network dynamics using multi-electrode arrays

使用多电极阵列进行 APOE 对神经元网络动力学的影响

• 批准号: 8786199
• 负责人: Gustavo A Rodriguez
• 金额: $ 2.56万
• 依托单位: GEORGETOWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8786199
• 关键词: Affect; Aftercare; Aging; Agonist; Alleles; Alzheimer' s Disease; Alzheimer' s disease risk; Apolipoprotein E; Brain; Cell Culture Techniques; Cells; Chemicals; Cholesterol Homeostasis; Complement; Confocal Microscopy; Data Analyses; Development; Disease; Disease susceptibility; E protein; Electrodes; Excitatory Synapse; Forskolin; Genotype; Glycoproteins; Harvest; Health; Human; Impaired cognition; In Vitro; Individual; Inflammation; Knock-in Mouse; LDL-Receptor Related Protein 1; Laboratories; Lead; Learning; Life; Link; Lipids; Lipoprotein (a); Long-Term Effects; Long-Term Potentiation; Measures; Memory; Modeling; Modification; Mus; Nerve Degeneration; Neuroglia; Neurons; Pathogenesis; Pathology; Peptides; Play; Population; Probability; Process; Property; Protein Isoforms; Proteins; Research Proposals; Risk; Risk Factors; Role; Rolipram; Series; Signal Transduction; Site; Synapses; Synaptic plasticity; System; Testing; Therapeutic; Time; Tissues; Vertebral column; Western Blotting; apolipoprotein E-2; apolipoprotein E-3; apolipoprotein E-4; base; cognitive function; density; electrical measurement; genetic risk factor; immunocytochemistry; in vitro Model; indexing; insight; lipid transport; memory process; mimetics; neurodevelopment; neuron development; neurotransmission; novel strategies; promoter; pup; receptor; relating to nervous system; research study; synaptogenesis

DESCRIPTION (provided by applicant): Apolipoprotein E (apoE) is a lipoprotein-associated glycoprotein synthesized in the CNS by glial cells, responsible for lipid transport within the brai. It has also been linked to a variety of CNS functions, including: neurodevelopment, inflammation, and synaptic plasticity. Importantly, APOE is the strongest genetic risk factor for the development of Alzheimer's disease (AD); it affects processes early in disease development and is known to influence normal brain function in the absence of AD pathology. There are three common human alleles: APOE-ε2, APOE-ε3, and APOE-ε4. Compared to non-ε4 carriers, a single copy of the ε4 allele confers an increased risk of 2- to 3-fold, while two ε4 alleles dramatically increase AD risk by 12-fold. At present, the mechanisms underlying apoE4-associated AD risk are unknown. My overarching hypothesis is that APOE genotype affects normal brain function before AD pathogenesis, specifically by affecting the development and network activity of organized neuronal populations in the brain. The objective of this research proposal is to investigate: 1) whether APOE genotype affects the functional development of neuronal networks in vitro; and 2) how apoE affects activity-induced network dynamics and excitatory neurotransmission. To test these objectives, I will first assess the formation and functional properties of neuronal networks in culture using multi-electrode arrays (MEA) (Aim 1). The MEA allows simultaneous measurement of electrical activity at 59 sites in a neuronal culture system. Cortical tissue will be harvested from APOE Targeted Replacement (TR) mice, a knock-in model expressing human APOE in place of murine APOE, and cultured onto MEAs for repeated electrophysiological recording as neuronal networks develop. This in vitro model allows me to test the contribution of each apoE isoform on neuronal networks, effectively reducing confounds present in other cell-based systems. I hypothesize that apoE4 may negatively impact the development of neuronal networks and cause overall decreased network activity compared to apoE2 or apoE3. Next, I will assess the influence of APOE genotype on activity-induced excitation and neuronal network dynamics using chemical Long-Term Potentiation (cLTP) (Aim 2). MEAs allow simple pharmacologic manipulation of apoE levels and signaling during cLTP to mechanistically determine the role apoE isoforms and its receptors play in activity-induced network dynamics. I hypothesize that apoE4 negatively affects cLTP-induced network dynamics. This interdisciplinary proposal represents a novel approach to understanding how APOE genotype contributes to large scale network formation and neuronal population activity. If my hypotheses are correct, then the information gained by these studies will be critical for the development of preventative therapeutics that compensate for apoE4-related brain changes.

描述（由申请人提供）：载脂蛋白E（apoE）是一种脂蛋白相关糖蛋白，由神经胶质细胞在CNS中合成，负责脑内的脂质转运。它还与各种CNS功能有关，包括：神经发育，炎症和突触可塑性。重要的是，APOE是阿尔茨海默病（AD）发展的最强遗传风险因素;它影响疾病发展的早期过程，并且已知在没有AD病理的情况下影响正常脑功能。有三种常见的人类等位基因：APOE-ε2、APOE-ε3和APOE-ε4。与非ε4携带者相比，ε4等位基因的单个拷贝赋予2至3倍的风险增加，而两个ε4等位基因使AD风险显著增加12倍。目前，apoE 4相关AD风险的潜在机制尚不清楚。我的总体假设是，APOE基因型在AD发病前影响正常的脑功能，特别是通过影响大脑中有组织的神经元群体的发育和网络活动。本研究的目的是探讨：1）APOE基因型是否影响体外神经元网络的功能发育; 2）apoE如何影响活动诱导的网络动力学和兴奋性神经传递。为了测试这些目标，我将首先使用多电极阵列（MEA）（目标1）评估培养中神经元网络的形成和功能特性。MEA允许同时测量神经元培养系统中59个位点的电活动。将从APOE靶向置换（TR）小鼠（表达人APOE代替鼠APOE的敲入模型）中收获皮质组织，并在MEA上培养，以在神经元网络发育时进行重复电生理记录。这种体外模型使我能够测试每个apoE亚型对神经元网络的贡献，有效地减少了其他基于细胞的系统中存在的混淆。我推测apoE 4可能会对神经网络的发育产生负面影响，并导致与apoE 2或apoE 3相比网络活动总体下降。接下来，我将使用化学长时程增强（cLTP）评估APOE基因型对活动诱导的兴奋和神经元网络动力学的影响（目的2）。MEA允许在cLTP期间对apoE水平和信号传导进行简单的药理学操作，以机械地确定apoE亚型及其受体在活性诱导的网络动力学中的作用。我假设apoE 4对cLTP诱导的网络动态产生负面影响。这一跨学科的建议代表了一种新的方法来了解APOE基因型如何有助于大规模网络的形成和神经元群体的活动。如果我的假设是正确的，那么这些研究所获得的信息将对开发预防性治疗方法，弥补apoE 4相关的大脑变化至关重要。