An integrated multi-layer 3D-fabrication of PDA/RGD coated graphene loaded PCL nanoscaffold for peripheral nerve restoration

Abstract

As a conductive nanomaterial, graphene has huge potentials in nerve function restoration by promoting electrical signal transduction and metabolic activities with unique topological properties. Polydopamine (PDA) and arginylglycylaspartic acid (RGD) can improve cell adhesion in tissue engineering. Here we report an integrated 3D printing and layer-by-layer casting (LBLC) method in multi-layered porous scaffold fabrication. The scaffold is composed of single-layered graphene (SG) or multi-layered graphene (MG) and polycaprolactone (PCL). The electrically conductive 3D graphene scaffold can significantly improve neural expression both in vitro and in vivo. It promotes successful axonal regrowth and remyelination after peripheral nerve injury. These findings implicate that graphene-based nanotechnology have great potentials in peripheral nerve restoration in preclinical and clinical application.

Enhancement of sciatic nerve regeneration with dual delivery of vascular endothelial growth factor and nerve growth factor genes

“…Therefore, here we did not observe there exist biologically synergistic recovery effect between VEGF and NGF. However, we think it may be caused by the short term recovery time we used in this study (4 weeks), as it's usually reported to last for 8 weeks or even longer for nerve recovery [8,9].…”

“…Peripheral sciatic nerve crush injury model was established on Sprague Dawley (SD) rats to evaluate the therapeutic effect of PDAPEI/pDNA polyplexes. All surgical operations followed instructions in published studies [8,9,35,36]. Briefly, SD rats (weight of 150 ± 10 g) were maintained in the SPF environment for 1 week and then anesthetized by 10% chloral hydrate (0.3 mL/kg) via intraperitoneal injection.…”

“…However, problems of low success rate of surgery, limited supply of donor nerves, insufficiency in large nerve gaps and inherent damage to donor Fang et al J Nanobiotechnol (2020) 18:46 sites have posed a huge challenge to the clinical use of autologous nerve grafting [6,7]. Currently, recovery with tissue-engineered methods is gradually becoming an alternative strategy for sciatic nerve reconstruction [8][9][10]. However, after having an overview of reported studies on tissue-engineered nerve grafting, we found that most pre-clinical researches focused on the role of neurogenesis in the peripheral nerve recovery, while the angiogenesis effect of blood vessels were often ignored [11].…”

Current Advances in the Utilization of Polydopamine Nanostructures in Biomedical Therapy

“…In terms of tissue engineering, PDA has been previously proven to be beneficial for cell attachment, and the utilization of PDA coatings in this field has been reported. For instance, PDA and arginylglycylaspartic acid were deposited onto a 3D graphene framework via the layer‐by‐layer method to prepare porous scaffolds for the adhesion and expression of neural cells both in vitro and in vivo . In a different study, Pacelli et al employed PDA coating to enhance the adsorption of dexamethasone onto a hydrogel arising from alginate and gelatin methacrylamide, which was later used as a scaffold for the modulation of osteogenic differentiation.…”

Multilayered spraying and gradient dotting of nanodiamond–polycaprolactone guidance channels for restoration of immune homeostasis

“…We previously reported integrated multilayer fabrication of polydopamine-and arginylglycylaspartic acid-modified graphene/polycaprolactone (PCL) conduits in the application of long-range sciatic nerve defect regeneration. Conductive graphene-based conduits can greatly increase neural expression and improve axonal regeneration and remyelination 10 . We also discussed GO/PCL conduits via integration molding and evaluated their potential in stimulating angiogenesis to promote sciatic nerve defect repair.…”