Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
Small. 2012 Sep 24;8(18):2869-77. doi: 10.1002/smll.201200715. Epub 2012 Jul 2.
In recent years, the utilization of nanomaterials such as carbon nanotubes (CNTs) in the field of neuroscience has forever changed the approach to nerve-related research. The array of novel properties CNTs possess allows them to interact with neurons at the nanodimensional scale. In this study, a CNT rope substrate is developed to allow the electrical stimulation of neural stem cells (NSCs) in culture medium and the in situ observation of the response of these stem cells after stimulation. CNTs are synthesized by chemical vapor deposition and prepared into a ropelike structure with a diameter of 1 mm and length of 1.5 cm. NSCs are differentiated on the CNT rope substrate while the direction of neurite outgrowth, phenotype, and maturity of the NSCs are analyzed. Fluorescence and scanning electron microscopy demonstrate that neurite extension favors the direction of the spiral topography on the CNT rope. NSCs plated on CNT ropes are boosted towards differentiated neurons in the early culture stage when compared to conventional tissue culture plates via the analysis of neuronal gene and protein expressions by quantitative polymerase chain reaction and immunostaining, respectively. Furthermore, a set of electrical stimulation parameters (5 mV, 0.5 mA, 25 ms intermittent stimulation) promotes neuronal maturity while also increasing the speed of neurite outgrowth. These results indicate that an electroconductive CNT rope substrate along with electrical stimulation may have a synergistic effect on promoting neurite elongation and boosting effects on the differentiation of NSCs into mature neuronal cells for therapeutic application in neural regeneration.
近年来，碳纳米管（CNT）等纳米材料在神经科学领域的应用彻底改变了神经相关研究的方法。CNT 所具有的一系列新颖特性使其能够在纳米尺度上与神经元相互作用。在这项研究中，开发了一种 CNT 绳状基底，以允许在培养基中对神经干细胞（NSC）进行电刺激，并原位观察刺激后这些干细胞的反应。通过化学气相沉积合成 CNT，并制备成直径为 1 毫米、长度为 1.5 厘米的绳状结构。在 CNT 绳状基底上分化 NSC，同时分析神经突生长的方向、NSC 的表型和成熟度。荧光和扫描电子显微镜表明，神经突的延伸有利于 CNT 绳状螺旋拓扑结构的方向。通过定量聚合酶链反应和免疫染色分别分析神经元基因和蛋白质表达，与传统的组织培养板相比，在早期培养阶段，在 CNT 绳上种植的 NSCs 被推向分化神经元，从而得到增强。此外，一组电刺激参数（5 mV、0.5 mA、25 ms 间歇刺激）可促进神经元成熟，同时也加快神经突生长速度。这些结果表明，导电 CNT 绳状基底和电刺激可能对促进神经突伸长具有协同作用，并能增强 NSCs 向成熟神经元细胞分化的作用，从而在神经再生的治疗应用中具有重要意义。
