Mechanisms of Age-related Cognitive Decline in the Rhesus Monkey

在恒河猴正常衰老期间，背外侧前额叶皮质(LPFC)中的锥体细胞 经历可能与认知障碍相关的重大结构和功能变化，而 初级视皮层(V1)的锥体细胞相对较少。对此的总体假设是 项目是与V1相比，LPFC中神经元和相关网络在衰老过程中的选择性脆弱性 是由于更容易受到氧化应激、炎症和血管功能障碍的影响 LPFC比V1中的低。我们进一步假设，对强效抗氧化剂和抗炎药物的干预 多酚姜黄素将在多个层面上预防或减少与年龄相关的功能障碍-从分子到 行为层面。本项目有三个目标：1)评估生物标志物和超微结构特征 V1和dlPFC神经膜。将使用~30个蛋白质生物标记物的原位免疫荧光复合 用GE Global确定神经元、神经胶质细胞、血管和周围神经束的分子表型 专为脑组织量身定做的研究平台，可实现高效率的定量多标记分析 吞吐量。用2D和3D电子显微镜观察抑制性和兴奋性突触、线粒体、髓鞘 神经元的轴突以及小胶质细胞和血管分子将被定量表征。2)至 描述第3层(L3)锥体神经元的生理和形态特征 恒河猴成年后V1和dlPFC的中间神经元。使用全细胞膜片钳 我们将评估被动膜属性、AP放电模式和潜在的离子电流，如 L3兴奋性和抑制性神经元的兴奋性和抑制性突触后电流 PFC和V1。然后我们将表征形态属性(例如，树枝状拓扑、密度和 树突棘和神经递质受体和转运体分布的详细形态，以及 这些神经元的氧化应激标志物)的免疫组织化学和超高分辨率 共聚焦激光扫描显微镜。3)使用V1和dlPFC网络的计算模型来预测 AIMS 1中揭示的变化在单个神经元、网络和行为水平上的功能后果 和2.LPFC和V1神经元的简化模型将被纳入到能够 持久的神经活动、动眼空间工作记忆和视觉定向调节。是独一无二的 建议是最先进的解剖学、生理学和计算方法的结合 以及在控制条件下和后续条件下对衰老猴子的并行行为评估 用姜黄素进行治疗。该项目将在以下方面产生全新的、急需的信息 老化灵长类动物认知衰退的神经基础并为了解具体情况提供了重要的见解 保护性抗炎抗氧化剂在正常衰老过程中的作用机制。

During normal aging in the rhesus monkey, pyramidal cells in the dorsolateral prefrontal cortex (LPFC) undergo significant structural and functional changes that are likely associated with cognitive impairment, while pyramidal cells in the primary visual cortex (V1) are comparatively spared. The overall hypothesis of this project is that selective vulnerability of neurons and associated networks in LPFC compared to V1 during aging is due to a greater susceptibility to increases in oxidative stress, inflammation, and vascular dysfunction in LPFC than in V1. We further hypothesize that intervention with the potent antioxidant and anti-inflammatory polyphenol curcumin will prevent or reduce age-related dysfunction on multiple scales- from the molecular to the behavioral level. This project has three aims: 1) To assess the biomarker and ultrastructural characteristics of V1 and dlPFC neuropil. In situ immunofluorescence multiplexing of ~30 protein biomarkers will be used to determine the molecular phenotype of neurons, glia, vasculature and surrounding neuropil with a GE Global Research platform tailored for use in brain tissue, enabling quantitative, multimarker analyses with high throughput. Using 2D and 3D electron microscopy, inhibitory and excitatory synapses, mitochondria, myelin and axons of neurons as well as microglia and vascular elements will be quantitatively characterized. 2) To characterize the physiological and morphological properties of layer 3 (L3) pyramidal neurons and of interneurons in V1 and dlPFC across the adult lifespan of rhesus monkeys. Using whole-cell patch-clamp recordings we will assess passive membrane properties, AP firing patterns and underlying ionic currents, as well as excitatory and inhibitory postsynaptic currents of L3 excitatory and inhibitory neurons in in vitro slices of PFC and V1. We will then characterize the morphological properties (e.g. dendritic topology, density and detailed morphology of dendritic spines and neurotransmitter receptor and transporter distribution, as well as oxidative stress markers) of these same neurons using immunohistochemistry and ultra-high resolution confocal laser scanning microscopy. 3) To use computational models of V1 and dlPFC networks to predict the functional consequences—at the single neuron, network and behavioral levels—of changes revealed in Aims 1 and 2. Simplified models of LPFC and V1 neurons will be incorporated into model networks capable of persistent neural activity, oculomotor spatial working memory, and visual orientation tuning. Unique to this proposal is the combination of state-of-the art anatomical, physiological, and computational approaches together with concurrent behavioral assessment of the aging monkey under control conditions and following therapeutic treatment with curcumin. This project will yield entirely novel and critically needed information on the neural substrates of cognitive decline in the aging primate and provide important insight into the specific mechanisms of action of protective anti-inflammatory and anti-oxidants during normal aging.