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

Abstract

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.

In Vitro Evaluation of Biocompatibility of Uncoated Thermally Reduced Graphene and Carbon Nanotube-Loaded PVDF Membranes with Adult Neural Stem Cell-Derived Neurons and Glia

“…In addition, cells were plated on graphene composites, graphene oxides, or on reduced graphene oxides with different surface charges and degree of electrical, photo, and laser stimulation (Akhavan and Ghaderi, 2013a,b, 2014; Tu et al, 2013a, 2014; Akhavan et al, 2014, 2015; Guo et al, 2016a). Similarly, both uncoated and coated functionalized single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) as well as aligned CNTs and nanofibers have been reported to permit and stimulate neuronal growth and the formation of active synaptic contacts (Jan and Kotov, 2007; Malarkey et al, 2009; Cellot et al, 2011; Jin et al, 2011; Fabbro et al, 2013; Gupta et al, 2015; Vicentini et al, 2015). …”

Regenerative nanomedicine: current perspectives and future directions

“…Further, the microarray studies suggested the presence of the active repair process involving microglia in the absence of reactive gliosis. 65 Nanotechnology approaches can also be used to regenerate chronically injured nerve cells. An interesting study has shown that the incorporation of electrospun nanofibers, self-assembling peptides, and proregenerative cytokines into guidance channels of the chronic spinal cord injured rat model resulted in a well-developed vascular network, basal lamina, and myelin, which eventually leads to enhanced electrophysiological recovery.…”

Recent advances in bioactive 1D and 2D carbon nanomaterials for biomedical applications

“…155 In another study, immature spinal cord neurons isolated from neonatal rat spinal cords showed rapid growth on pyrolidine-functionalized MWCNT coated surfaces. 156 In an in vivo study, electrospun collagen-PCL-MWCNT fibrous scaffolds were shown to assist in the recovery of rat sciatic nerve defect models and prevented muscle atrophy. In the same study, the scaffold also supported Schwann cell adhesion and elongation.…”