Oriented Graphene Oxide Scaffold Promotes Nerve Regeneration in vitro and in vivo

Abstract

Xu Zhou,1,2,* Aolin Tang,2,3,* Chengjie Xiong,2,* Guoquan Zhang,2 Liangliang Huang,1,2 Feng Xu1,2 1The First School of Clinical Medicine, Southern Medical University, Guangzhou, 510515, People’s Republic of China; 2Department of Orthopaedics, General Hospital of Central Theater Command, Wuhan, 430070, People’s Republic of China; 3Department of Orthopaedics, Minda Hospital of Hubei Minzu University, Enshi, 445000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Liangliang Huang; Feng Xu, Department of Orthopaedics, General Hospital of Central Theater Command, Wuhan, 430070, People’s Republic of China, Email [email protected]; [email protected]: Treating peripheral nerve injuries (PNI) with defects remains challenging in clinical practice. The commercial conduits have shown suboptimal nerve regeneration and functional recovery due to their basic tubular design without electroactive and oriented topographical cues.Purpose: To develop a new scaffold with oriented microstructure and electroactive Graphene oxide (GO) and investigate its’ therapeutic effect on nerve regeneration in vitro and in vivo.Methods: This study employed a straightforward approach to co-spin PCL and GO, yielding an oriented hybrid nanofibrous scaffold known as the O-GO/PCL scaffold. The physical and chemical properties of nanofibrous scaffold were tested by scanning electron microscopy (SEM), transmission electron microscope (TEM), tensile test and so on. Primary Schwann cells (SCs) and dorsal root ganglia (DRG) were used to investigate the impact of the newly developed scaffolds on the biological behavior of neural cells in vitro. Transcriptome sequencing (mRNA-seq) was employed to probe the underlying mechanisms of the synergistic effect of electroactive GO and longitudinal topographic guidance on nerve regeneration. Furthermore, the developed O-GO/PCL scaffold was utilized to bridge a 10-mm sciatic nerve defect in rat, aiming to investigate its therapeutic potential for peripheral nerve regeneration in vivo.Results and discussion: The SEM and TEM revealed that the newly developed O-GO/PCL scaffold showed longitudinally oriented microstructure and GO particles were homogenously and uniformly distributed inside the nanofibers. Primary SCs were utilized to assess the biocompatibility of the GO-based scaffold, revealing that negligible cytotoxicity when GO concentration does not exceed 0.5%. In vitro analysis of nerve regeneration demonstrated that axons in the O-GO/PCL group exhibited an average length of 1054.88 ± 161.32 μm, significant longer than those in the other groups (P < 0.05). Moreover, mRNA sequencing results suggested that the O-GO/PCL scaffold could enhance nerve regeneration by upregulating genes associated with neural regeneration, encompassing ion transport, axon guidance and cell–cell interactions. Most importantly, we employed the O-GO/PCL scaffold to repair a 10-mm sciatic nerve defect in rat, resulting in augmented nerve regeneration, myelination, and functional recovery.Conclusion: The O-GO/PCL scaffold with oriented microstructure and electroactive GO represents a promising heral nerve reconstruction. Keywords: nanofibers, topographical guidance, electroactive, graphene oxide, nerve regeneration

Keywords

• nanofibers
• topographical guidance
• electroactive
• graphene oxide
• nerve regeneration.