Sun Ying, Florer Jane, Mayhew Christopher N, Jia Zhanfeng, Zhao Zhiying, Xu Kui, Ran Huimin, Liou Benjamin, Zhang Wujuan, Setchell Kenneth D R, Gu Jianguo, Grabowski Gregory A
Division of Human Genetics, Cincinnati Children's Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America.
Division of Human Genetics, Cincinnati Children's Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America.
PLoS One. 2015 Mar 30;10(3):e0118771. doi: 10.1371/journal.pone.0118771. eCollection 2015.
Gaucher disease (GD) is caused by insufficient activity of acid β-glucosidase (GCase) resulting from mutations in GBA1. To understand the pathogenesis of the neuronopathic GD, induced pluripotent stem cells (iPSCs) were generated from fibroblasts isolated from three GD type 2 (GD2) and 2 unaffected (normal and GD carrier) individuals. The iPSCs were converted to neural precursor cells (NPCs) which were further differentiated into neurons. Parental GD2 fibroblasts as well as iPSCs, NPCs, and neurons had similar degrees of GCase deficiency. Lipid analyses showed increases of glucosylsphingosine and glucosylceramide in the GD2 cells. In addition, GD2 neurons showed increased α-synuclein protein compared to control neurons. Whole cell patch-clamping of the GD2 and control iPSCs-derived neurons demonstrated excitation characteristics of neurons, but intriguingly, those from GD2 exhibited consistently less negative resting membrane potentials with various degree of reduction in action potential amplitudes, sodium and potassium currents. Culture of control neurons in the presence of the GCase inhibitor (conduritol B epoxide) recapitulated these findings, providing a functional link between decreased GCase activity in GD and abnormal neuronal electrophysiological properties. To our knowledge, this study is first to report abnormal electrophysiological properties in GD2 iPSC-derived neurons that may underlie the neuropathic phenotype in Gaucher disease.
戈谢病（GD）是由GBA1基因突变导致酸性β-葡萄糖苷酶（GCase）活性不足引起的。为了解神经病变型GD的发病机制，从三名2型戈谢病（GD2）患者以及两名未受影响（正常人和GD携带者）个体分离出的成纤维细胞中生成了诱导多能干细胞（iPSC）。这些iPSC被转化为神经前体细胞（NPC），并进一步分化为神经元。亲代GD2成纤维细胞以及iPSC、NPC和神经元的GCase缺乏程度相似。脂质分析显示，GD2细胞中的葡萄糖神经鞘氨醇和葡萄糖神经酰胺增加。此外，与对照神经元相比，GD2神经元的α-突触核蛋白水平升高。对GD2和对照iPSC来源的神经元进行全细胞膜片钳记录，结果显示了神经元的兴奋特性，但有趣的是，GD2来源的神经元静息膜电位始终较负，动作电位幅度、钠电流和钾电流均有不同程度的降低。在GCase抑制剂（环硫醇环氧物）存在的情况下培养对照神经元，重现了这些发现，这表明GD中GCase活性降低与异常的神经元电生理特性之间存在功能联系。据我们所知，本研究首次报道了GD2 iPSC来源的神经元存在异常电生理特性，这可能是戈谢病神经病变表型的基础。
