Biocompatible heterogeneous porous gel matrix NeuroGel(TM) promotes regeneration of rat sciatic nerve within tubular silicone prosthesis (experimental study).

Abstract

The purpose of this study was to investigate the ability of NeuroGel™ to promote and enhance the regeneration of rat sciatic nerve within a 10-mm gap using silicone tubular prosthesis, and to evaluate and compare the regeneration outcomes versus autologous grafting. The 10-mm gap of rat sciatic nerve was bridged through silicone tubular prosthesis filled with dehydrated NeuroGel™, and NeuroGel™ saturated with rat NGF-B (NG30-NGG60, NGgfB30-NGgfB60). To assess the regeneration of the peripheral nerve we utilized three general and most commonly applied methods: electrophysiologic, hystomorphometric, and functional methods. The average M-wave amplitude (AMW index), or the intermediary index of the number of regenerated axons, in animal groups NGG60 and NGgfB60 60 days post-op was: 2.44 ± 0.57 mV and 1.87 ± 0.48 mV. These indices were statistically lower compared to the indices obtained after autologous grafting. The average impulse conduction velocity along motor fibers (VMF index), or the intermediary index of myelination rate, was: 13.3 mm/ms and 13.3 mm/ms, respectively, statistically equal to indices obtained after autologous grafting. The average density (D) of regenerated fibers (direct numerical indicator in contrast to intermediary AMW index) in animal groups NGG60 and NGgfB60 was: 4,920 ± 178.88 and 5,340 ± 150.33 per mm(2), respectively. These indices were statistically higher versus indices obtained after autologous grafting. Myelination rates of regenerated fibers in animal groups NGG60 and NGgfB60 were 73 and 86 %, respectively. They were also statistically higher. The average sciatic functional index (SFI) in NGG60 and NGgfB60 was: -25.57 ± 3.05 and -24.124 ± 4.8, respectively, which is statistically equal to indices obtained after autologous grafting. Neurogel™ strongly promotes the regeneration of rat sciatic nerve within silicone tubular prosthesis. After bridging a 10-mm gap through silicone prosthesis with Neurogel™ or Neurogel™ +NGF-B-modified intraluminal space, the myelination rate of regenerated axons of rat sciatic nerve appeared to be higher, and the axon count and functional recovery is similar to results seen with the autografting technique.