PDF(Pubmed)
Abstract：
Cofilactin rod pathology, which can initiate synapse loss, has been extensively studied in rodent neurons, hippocampal slices, and in vivo mouse models of human neurodegenerative diseases such as Alzheimer\'s disease (AD). In these systems, rod formation induced by disease-associated factors, such as soluble oligomers of Amyloid-β (Aβ) in AD, utilizes a pathway requiring cellular prion protein (PrPC), NADPH oxidase (NOX), and cytokine/chemokine receptors (CCR5 and/or CXCR4). However, rod pathways have not been systematically assessed in a human neuronal model. Here, we characterize glutamatergic neurons differentiated from human-induced pluripotent stem cells (iPSCs) for the formation of rods in response to activators of the PrPC-dependent pathway. Optimization of substratum, cell density, and use of glial-conditioned medium yielded a robust system for studying the development of Aβ-induced rods in the absence of glia, suggesting a cell-autonomous pathway. Rod induction in younger neurons requires ectopic expression of PrPC, but this dependency disappears by Day 55. The quantification of proteins within the rod-inducing pathway suggests that increased PrPC and CXCR4 expression may be factors in the doubling of the rod response to Aβ between Days 35 and 55. FDA-approved antagonists to CXCR4 and CCR5 inhibit the rod response. Rods were predominantly observed in dendrites, although severe cytoskeletal disruptions prevented the assignment of over 40% of the rods to either an axon or dendrite. In the absence of glia, a condition in which rods are more readily observed, neurons mature and fire action potentials but do not form functional synapses. However, PSD95-containing dendritic spines associate with axonal regions of pre-synaptic vesicles containing the glutamate transporter, VGLUT1. Thus, our results identified stem cell-derived neurons as a robust model for studying cofilactin rod formation in a human cellular environment and for developing effective therapeutic strategies for the treatment of dementias arising from multiple proteinopathies with different rod initiators.
摘要：
Cofilactin棒病理学，可以引发突触丢失，已经在啮齿动物神经元中进行了广泛的研究，海马片,和人神经退行性疾病如阿尔茨海默病(AD)的体内小鼠模型。在这些系统中,由疾病相关因素诱导的杆形成，如AD中淀粉样蛋白-β(Aβ)的可溶性寡聚体，利用需要细胞朊病毒蛋白（PrPC）的途径，NADPH氧化酶(NOX),和细胞因子/趋化因子受体(CCR5和/或CXCR4)。然而,杆途径尚未在人类神经元模型中进行系统评估。这里,我们描述了从人诱导的多能干细胞(iPSCs)分化的谷氨酸能神经元在PrPC依赖性途径的激活剂作用下形成棒的过程.基质的优化，细胞密度，神经胶质条件培养基的使用产生了一个强大的系统，用于研究在没有神经胶质的情况下Aβ诱导的棒的发育，提示细胞自主途径。年轻神经元中的棒诱导需要PrPC的异位表达，但是这种依赖性在第55天消失了。杆诱导途径内蛋白质的定量表明，PrPC和CXCR4表达的增加可能是第35天和第55天之间杆对Aβ的反应加倍的因素。FDA批准的CXCR4和CCR5拮抗剂抑制杆反应。主要在树突中观察到棒，尽管严重的细胞骨架破坏阻止了超过40％的棒分配给轴突或树突。在没有神经胶质的情况下,在这种情况下，杆更容易被观察到，神经元成熟并激发动作电位，但不形成功能性突触。然而,含有PSD95的树突棘与含有谷氨酸转运体的突触前囊泡的轴突区域相关，VGLUT1。因此，我们的研究结果确定干细胞衍生的神经元是研究人类细胞环境中的cofilactin杆状蛋白形成和开发有效治疗策略的稳健模型,用于治疗由不同杆状蛋白引发剂引起的多种蛋白病引起的痴呆.
