NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, Pisa, 56127, Italy.
CNR-IOM, Area Science Park, S.S. 14, km 163.5, Basovizza, TS, Italy.
Sci Rep. 2020 Feb 28;10(1):3742. doi: 10.1038/s41598-020-60745-5.
Contact interaction of neuronal cells with extracellular nanometric features can be exploited to investigate and modulate cellular responses. By exploiting nanogratings (NGs) with linewidth from 500 nm down to 100 nm, we here study neurite contact guidance along ultra-small directional topographies. The impact of NG lateral dimension on the neuronal morphotype, neurite alignment, focal adhesion (FA) development and YAP activation is investigated in nerve growth factor (NGF)-differentiating PC12 cells and in primary hippocampal neurons, by confocal and live-cell total internal reflection fluorescence (TIRF) microscopy, and at molecular level. We demonstrate that loss of neurite guidance occurs in NGs with periodicity below 400 nm and correlates with a loss of FA lateral constriction and spatial organization. We found that YAP intracellular localization is modulated by the presence of NGs, but it is not sensitive to their periodicity. Nocodazole, a drug that can increase cell contractility, is finally tested for rescuing neurite alignment showing mild ameliorative effects. Our results provide new indications for a rational design of biocompatible scaffolds for enhancing nerve-regeneration processes.
神经元细胞与细胞外纳米特征的接触相互作用可用于研究和调节细胞反应。通过利用线宽从 500nm 减小到 100nm 的纳米光栅 (NG),我们在此研究了沿着超小定向形貌的神经突接触导向。通过共聚焦和活细胞全内反射荧光 (TIRF)显微镜以及分子水平,研究了 NG 横向尺寸对神经生长因子 (NGF) 分化的 PC12 细胞和原代海马神经元的神经元形态、神经突取向、焦点黏附 (FA) 发育和 YAP 激活的影响。我们证明,周期性小于 400nm 的 NG 中会发生神经突导向丧失,并且与 FA 侧向收缩和空间组织的丧失相关。我们发现 YAP 细胞内定位受 NG 的调制,但对其周期性不敏感。最后,测试了药物 nocodazole 来恢复神经突取向,显示出轻度的改善作用,nocodazole 是一种可以增加细胞收缩性的药物。我们的结果为增强神经再生过程的生物相容性支架的合理设计提供了新的依据。