Institute of Neurogenetics, University of Lübeck, Germany; Department of Neurology, University of Lübeck, Germany.
Department of Neurology, Hannover Medical School, Germany.
Exp Neurol. 2018 Oct;308:47-58. doi: 10.1016/j.expneurol.2018.06.012. Epub 2018 Jun 23.
X-linked dystonia-parkinsonism (XDP) is a neurodegenerative disorder endemic to Panay Island (Philippines). Patients present with generalizing dystonia and parkinsonism. Genetic changes surrounding the TAF1 (TATA-box binding protein associated factor 1) gene have been associated with XDP inducing a degeneration of striatal spiny projection neurons. There is little knowledge about the pathophysiology of this disorder. Our objective was to generate and analyze an in-vitro model of XDP based on striatal neurons differentiated from induced pluripotent stem cells (iPSC). We generated iPSC from patient and healthy control fibroblasts (3 affected, 3 controls), followed by directed differentiation of the cultures towards striatal neurons. Cells underwent characterization of immunophenotype as well as neuronal function, glutamate receptor properties and calcium dynamics by whole-cell patch-clamp recordings and calcium imaging. Furthermore, we evaluated expression levels of AMPA receptor subunits and voltage-gated calcium channels by quantitative real-time PCR. We observed no differences in basic electrophysiological properties. Application of the AMPA antagonist NBQX led to a more pronounced reduction of postsynaptic currents in XDP neurons. There was a higher expression of AMPA receptor subunits in patient-derived neurons. Basal calcium levels were lower in neurons derived from XDP patients and cells with spontaneous calcium transients were more frequent. Our data suggest altered glutamate response and calcium dynamics in striatal XDP neurons.
X 连锁型肌张力障碍-帕金森病（XDP）是一种在菲律宾帕奈岛流行的神经退行性疾病。患者表现为全身性肌张力障碍和帕金森病。TAF1（TATA 框结合蛋白相关因子 1）基因周围的遗传变化与 XDP 诱导纹状体棘突投射神经元变性有关。目前对这种疾病的病理生理学知之甚少。我们的目的是基于诱导多能干细胞（iPSC）分化的纹状体神经元，生成和分析 XDP 的体外模型。我们从患者和健康对照成纤维细胞（3 例受影响，3 例对照）中生成 iPSC，然后对培养物进行定向分化为纹状体神经元。通过全细胞膜片钳记录和钙成像技术对细胞进行免疫表型以及神经元功能、谷氨酸受体特性和钙动力学的特征分析。此外，我们通过定量实时 PCR 评估 AMPA 受体亚基和电压门控钙通道的表达水平。我们观察到基本电生理特性没有差异。应用 AMPA 拮抗剂 NBQX 导致 XDP 神经元突触后电流的减少更为明显。在源自患者的神经元中，AMPA 受体亚基的表达更高。源自 XDP 患者的神经元中的基础钙水平较低，且具有自发性钙瞬变的细胞更为频繁。我们的数据表明，纹状体 XDP 神经元的谷氨酸反应和钙动力学发生改变。
