Biomimetic multi-channel nerve conduits with micro/nanostructures for rapid nerve repair
Xinqing Wang, Shuo Chen, Xiaolei Chen, Juan Wu, Zhenhua Huang, Jing Wang, Fangping Chen, Changsheng Liu
Abstract
Peripheral nervous system (PNS) injuries often lead to significant sensory and motor impairments. Traditional artificial nerve conduits, lacking anisotropic structures, have been associated with prolonged repair time and failures in nerve regeneration. This study aimed to address these challenges by developing a novel approach for rapid repair of peripheral nerve injuries (PNI). A 3D oriented fibers scaffold featuring distinct radial (RFs) and longitudinal (LFs) fibers orientations was engineered using coaxial electrospinning and gas directional foaming techniques. This scaffold was then integrated with a shape memory conduit to form a directional multi-channel nerve conduit with micro/nanostructures. The results revealed that the grooved surface of the fibers significantly improved cellular directional guidance, effectively facilitating the migration of SCs from the periphery towards the center and from the base to the apex of the scaffold. In a rat model with a 10 mm nerve defect, the ND-PLATMC/LF ND-PCL scaffold significantly enhanced nerve regeneration and motor function recovery within 4 weeks. These results suggest the potential of this innovative scaffold for efficient repair of the nerve injuries. • Inspired by the xylem structure of Redwoods, three-dimensional double-oriented PCL/PVP fiber scaffolds with controlled micro-nano grooves were prepared by a combination of coaxial electrospinning, gas foaming and in-situ pore forming technologies. • Radial foaming (RF) and longitudinal foaming (LF) of PCL/PVP fiber scaffolds allowed flexible adjustment of pore sizes, along with nano-scale grooves varying in width and depth within individual fibers. • The 3D fibrous scaffold guide'd long distance (>12 mm) directional migration of cells and promoted axonal elongation with the expression of neuroblast -related genes nearly doubling that of the control group. • The channel micro-nano composite nerve catheter demonstrates rapid and high-quality repair of a 10 mm sciatic nerve defect in rats, highlighting its significant potential for nerve regeneration and motor function recovery.