Electrical stimulation alters protein adsorption and nerve cell interactions with electrically conducting biomaterials
Electrical stimulation alters protein adsorption and nerve cell interactions with electrically conducting biomaterials
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DOI：
10.1016/s0142-9612(00)00344-6
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发表时间：
2001-05-01
期刊：
影响因子：
14
通讯作者：
Schmidt, CE
中科院分区：
文献类型：
--
作者：
Kotwal, A;Schmidt, CE
电荷已被证明可以促进神经再生；然而，这种影响的机制尚不清楚。一种假设是，电刺激改变了细胞外基质分子的局部电场，改变了蛋白质的吸附。我们已经研究了这一假设——电刺激增加了血清蛋白，特别是纤维连接蛋白（FN）对导电聚合物聚吡咯（PP）的吸附，从而增加了神经突的延伸。之所以使用PP，是因为电刺激PP可以显著促进神经突生长，更重要的是，PP可以在体内形成引导神经再生的导管。在这里，我们观察了电刺激对蛋白质吸附的影响，当电流施加于PP(1)在蛋白质吸附期间（即时刺激）和(2)在蛋白质吸附后几小时（延迟刺激）。我们发现直接刺激PP会增加纯化FN和含血清溶液对FN的吸附。相应的，在PP膜上生长的PC-12细胞在直接刺激时表达了更长的神经突。然而，对于延迟刺激，没有观察到吸附或神经突生长的显着差异。这些研究表明，直接电刺激增加的FN吸附可以解释电刺激PP上神经突延伸增强的原因。版权所有。
Electrical charges have been shown to enhance nerve regeneration; however, the mechanisms for this effect are unclear. One hypothesis is that an electrical stimulus alters the local electrical fields of extracellular matrix molecules, changing protein adsorption. We have investigated this hypothesis - that electrical stimulation increases the adsorption of serum proteins, specifically fibronectin (FN), to the electrically conducting polymer polypyrrole (PP), thereby, increasing neurite extension. PP was used because electrical stimulation of PP has been shown to significantly enhance neurite outgrowth, and more importantly, PP can be formed into conduits to guide nerve regeneration in vivo. Here, we looked at the effects of electrical stimulation on protein adsorption when an electrical current was applied to PP (1)during protein adsorption (immediate stimulation) and (2) several hours after protein adsorption (delayed stimulation). We found that immediate stimulation of PP increases FN adsorption from purified FN and serum-containing solutions. Correspondingly, PC-12 cells grown on PP films that had been previously adsorbed with FN during immediate stimulation expressed longer neurites. However, for delayed stimulation, no significant differences in adsorption or neurite outgrowth were observed. These studies suggest that increased FN adsorption with immediate electrical stimulation may explain enhanced neurite extension on electrically stimulated PP. (C) 2001 Elsevier Science Ltd. All rights reserved.