Graduate School of Life Sciences, Toyo University, Ora-gun, Gunma, Japan.
Nanotechnology. 2010 Mar 19;21(11):115101. doi: 10.1088/0957-4484/21/11/115101. Epub 2010 Feb 22.
Low concentrations (0.11-1.7 microg ml(-1)) of functionalized carbon nanotubes (CNTs), which are multi-walled CNTs modified by amino groups, when added with nerve growth factor (NGF), promoted outgrowth of neuronal neurites in dorsal root ganglion (DRG) neurons and rat pheochromocytoma cell line PC12h cells in culture media. The quantity of active extracellular signal-regulated kinase (ERK) was higher after the addition of both 0.85 microg ml(-1) CNTs and NGF than that with NGF alone. CNTs increased the number of cells with neurite outgrowth in DRG neurons and PC12h cells after the inhibition of the ERK signaling pathway using a mitogen-activated protein kinase (MAPK)/ERK kinase (MEK) inhibitor. Active ERK proteins were detected in MEK inhibitor-treated neurons after the addition of CNTs to the culture medium. These results demonstrate that CNTs may stimulate neurite outgrowth by activation of the ERK signaling pathway. Thus, CNTs are biocompatible and are promising candidates for biological applications and devices.
低浓度（0.11-1.7 μg/ml）的功能化碳纳米管（CNTs），即经氨基基团修饰的多壁 CNTs，与神经生长因子（NGF）一同加入时，可促进体外培养的背根神经节（DRG）神经元和大鼠嗜铬细胞瘤 PC12h 细胞的神经元突起生长。与单独使用 NGF 相比，加入 0.85 μg/ml CNTs 和 NGF 后，细胞外信号调节激酶（ERK）的活性更高。使用丝裂原活化蛋白激酶（MAPK）/ERK 激酶（MEK）抑制剂抑制 ERK 信号通路后，CNTs 可增加 DRG 神经元和 PC12h 细胞中具有突起生长的细胞数量。在向培养基中添加 CNTs 后，可在经 MEK 抑制剂处理的神经元中检测到活性 ERK 蛋白。这些结果表明，CNTs 可能通过激活 ERK 信号通路来刺激突起生长。因此，CNTs 具有生物相容性，是生物应用和器件的有前途的候选材料。
