Mechanisms of Age-related Cognitive Decline in the Rhesus Monkey

在恒河猴的正常衰老过程中，背外侧前额叶皮层（LPFC）的锥体细胞 发生可能与认知障碍相关的显著结构和功能变化， 初级视觉皮层（V1）中的锥体细胞相对较少。这个问题的总体假设 该项目是在老化过程中，与V1相比，LPFC中神经元和相关网络的选择性脆弱性 是由于更大的易感性增加氧化应激，炎症，血管功能障碍， LPFC比V1。我们进一步假设，用有效的抗氧化剂和抗炎剂干预， 多酚姜黄素将预防或减少与年龄相关的功能障碍在多个尺度-从分子到 行为层面。本课题的主要目的有三：1）研究其生物标志物和超微结构特征 V1和dlPFC神经毡的变化。将使用~30种蛋白质生物标志物的原位免疫荧光多重检测， 用GE Global确定神经元、神经胶质、血管和周围神经元的分子表型 专为脑组织使用而定制的研究平台，能够进行定量、多标记物分析， 吞吐量使用二维和三维电子显微镜，抑制性和兴奋性突触，线粒体，髓鞘 并且神经元的轴突以及小胶质细胞和血管成分将被定量表征。2)到 表征第3层（L3）锥体神经元和神经元的生理和形态学特性， V1和dlPFC中的中间神经元在恒河猴的成年寿命中的变化。采用全细胞膜片钳 记录，我们将评估被动膜特性，AP放电模式和潜在的离子电流， 以及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，我们将描述形态学特性（例如，树枝状拓扑结构，密度和 树突棘和神经递质受体和转运蛋白分布的详细形态，以及 氧化应激标志物）的这些相同的神经元使用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 目标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能够 持续的神经活动、眼空间工作记忆和视觉定向调节。独特的这个 该建议是最先进的解剖学，生理学和计算方法的结合 同时在对照条件下对衰老猴进行行为评估， 用姜黄素治疗。该项目将产生完全新颖和急需的信息， 衰老灵长类动物认知能力下降的神经基质，并提供了重要的洞察力， 在正常衰老过程中保护性抗炎和抗氧化剂的作用机制。

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.