Adhesion to Carbon Nanotube Conductive Scaffolds Forces Action-Potential Appearance in Immature Rat Spinal Neurons

PLOS ONE, Dec 2019

In the last decade, carbon nanotube growth substrates have been used to investigate neurons and neuronal networks formation in vitro when guided by artificial nano-scaled cues. Besides, nanotube-based interfaces are being developed, such as prosthesis for monitoring brain activity. We recently described how carbon nanotube substrates alter the electrophysiological and synaptic responses of hippocampal neurons in culture. This observation highlighted the exceptional ability of this material in interfering with nerve tissue growth. Here we test the hypothesis that carbon nanotube scaffolds promote the development of immature neurons isolated from the neonatal rat spinal cord, and maintained in vitro. To address this issue we performed electrophysiological studies associated to gene expression analysis. Our results indicate that spinal neurons plated on electro-conductive carbon nanotubes show a facilitated development. Spinal neurons anticipate the expression of functional markers of maturation, such as the generation of voltage dependent currents or action potentials. These changes are accompanied by a selective modulation of gene expression, involving neuronal and non-neuronal components. Our microarray experiments suggest that carbon nanotube platforms trigger reparative activities involving microglia, in the absence of reactive gliosis. Hence, future tissue scaffolds blended with conductive nanotubes may be exploited to promote cell differentiation and reparative pathways in neural regeneration strategies.

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Adhesion to Carbon Nanotube Conductive Scaffolds Forces Action-Potential Appearance in Immature Rat Spinal Neurons

et al. (2013) Adhesion to Carbon Nanotube Conductive Scaffolds Forces Action-Potential Appearance in Immature Rat Spinal Neurons. PLoS ONE 8(8): e73621. doi:10.1371/journal.pone.0073621 Adhesion to Carbon Nanotube Conductive Scaffolds Forces Action-Potential Appearance in Immature Rat Spinal Neurons Alessandra Fabbro Antonietta Sucapane Francesca Maria Toma Enrica Calura Lisa Rizzetto Claudia Carrieri Paola Roncaglia Valentina Martinelli Denis Scaini Lara Masten Antonio Turco Stefano Gustincich Maurizio Prato (MP) Laura Ballerini Masaya Yamamoto, Institute for Frontier Medical Sciences, Kyoto University, Japan In the last decade, carbon nanotube growth substrates have been used to investigate neurons and neuronal networks formation in vitro when guided by artificial nano-scaled cues. Besides, nanotube-based interfaces are being developed, such as prosthesis for monitoring brain activity. We recently described how carbon nanotube substrates alter the electrophysiological and synaptic responses of hippocampal neurons in culture. This observation highlighted the exceptional ability of this material in interfering with nerve tissue growth. Here we test the hypothesis that carbon nanotube scaffolds promote the development of immature neurons isolated from the neonatal rat spinal cord, and maintained in vitro. To address this issue we performed electrophysiological studies associated to gene expression analysis. Our results indicate that spinal neurons plated on electro-conductive carbon nanotubes show a facilitated development. Spinal neurons anticipate the expression of functional markers of maturation, such as the generation of voltage dependent currents or action potentials. These changes are accompanied by a selective modulation of gene expression, involving neuronal and non-neuronal components. Our microarray experiments suggest that carbon nanotube platforms trigger reparative activities involving microglia, in the absence of reactive gliosis. Hence, future tissue scaffolds blended with conductive nanotubes may be exploited to promote cell differentiation and reparative pathways in neural regeneration strategies. - Funding: Funding provided by NEURONANO-NMP4-CT-2006-031847 CARBONANOBRIDGE- ERC-2008-227135 http://erc.europa.eu/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. These authors contributed equally to this work. Nanomaterials are increasingly used for organ engineering purposes [1,2]. Scaffolds with manufactured three-dimensional properties may promote cells reorganization into functional tissue. This possibility has driven a growing interest in studying physical-chemical features of scaffolds at the nano-scale, to activate cell-specific molecular machineries [14]. Scaffolds blended with various materials have been constructed for the repair of different tissues, such as bones, liver and other organs [1,2,57]. However, attempts to construct scaffolds for the repair of the central nervous system (CNS) have had limited success, because of its intrinsic complexity, low regenerative potential and anatomically restrictive nature, which pose a unique set of challenges [813]. Despite this fact, an increasing amount of studies in modern neuroscience addresses the ability of growth substrate topography or physical features in driving neuronal networks reconstruction. In cultured systems, the interaction of neurons with their growth substrate may influence neuron differentiation, morphology, adhesion and outgrowth [1319]. Our approach to address this issue was to incorporate neuronal cultures to artificial conductive nanostructures, namely carbon nanotubes. Recently, carbon nanotubes have attracted tremendous attention for the development of nano-bio hybrid systems able to govern cell-specific behaviors in cultured neuronal networks and explants [2027] and have been shown to promote proliferation of neonatal cardiac myocytes [28]. Carbon nanotubes are cylindrically shaped nanostructures, made of one or more concentric rolled-up graphene sheets, which possess peculiar properties including high surface area, high mechanical strength, ultra-light weight, rich electronic properties, and excellent chemical and thermal stability [29,30]. In vivo, carbon nanotubes have been shown to be a blood compatible and a suitable scaffold for bone regeneration [31,32] or, in vitro, for cultured synaptic network formation [2224,26,27,33] and neonatal cardiomyocyte maturation [28]. In the present work we investigate the interaction between carbon nanotube scaffolds and immature spinal cord neurons. Here we show that in vitro spinal neurons adherent to carbon nanotube substrates undergo a functional maturation characterized by an earlier appearance of voltage dependent currents and of action potentials. To address the mechanistic pathways between the enhan (...truncated)


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Alessandra Fabbro, Antonietta Sucapane, Francesca Maria Toma, Enrica Calura, Lisa Rizzetto, Claudia Carrieri, Paola Roncaglia, Valentina Martinelli, Denis Scaini, Lara Masten, Antonio Turco, Stefano Gustincich, Maurizio Prato, Laura Ballerini. Adhesion to Carbon Nanotube Conductive Scaffolds Forces Action-Potential Appearance in Immature Rat Spinal Neurons, PLOS ONE, 2013, Volume 8, Issue 8, DOI: 10.1371/journal.pone.0073621