ABSTRACT
Objective To explore the role of compound nerve conduit, made of nerve growth factors (NGF) encapsuled by biodegradable core-shell nanofibers through coaxial electrospinning, in regeneration of injured sciatic nerves in rats. Methods The compound nerve conduits were developed from the core-shell structured biodegradable nanofibers with P(LLA-CL) as a shell and BSA/NGF or BSA as a core through coaxial electrospinning. Seventy-two Sprague-Dawley rats were randomly divided into 4 even groups. The middle segments (10 mm) of the sciatic nerve were excised and the defects were repaired with sciatic nerve autograft (group A), with P(LLA-CL) conduit (group B), with PLLA-CL conduit and one injection of NGF (group C), and with P(LLA-CL)/NGF controlled-release conduit (group D), respectively. Morphologic and functional evaluations of nerve regeneration were done by gross observation, sciatic function index, neural electrophysiological examination, resumption rates of triceps weight, histological and ultrastructural observa-tion respectively in 1, 2, 3 months after the operation. Results Three months after the operation, although partial biodegradation and small cracks could be observed, conduits remained intact in outline. Based on the functional and histological observations, nerve regeneration, nerve fibers arrangement, myelination and nerve function reconstruction in the P(LLA-CL)/NGF controlled-release conduit (group D) were similar to those in nerve autograft (group A) and significantly superior to those in groups B and C (P<0.05). Conclusion As the P(LLA-CL)/NGF-controlled release conduit has favorable mechanical properties and biocompatibility, it can effectively promote regeneration of the sciatic nerve in rats.