Fabrication and transplantation of chitosan-selenium biodegradable nanocomposite conduit on transected sciatic nerve: a novel study in rat model.

Purpose : The improvement of techniques using conduits that connects the ends of damaged nerves and guides the growth of nerve fibers between the stumps, including adoption of natural or synthetic materials still is a challenge in peripheral nerve repair. The aim of the present novel study was to fabricate and transplant chitosan-selenium biodegradable nanocomposite conduit on transected sciatic nerve in rat model. Methods : In NORMAL group, the left sciatic nerve was exposed through a gluteal muscle incision and after careful hemostasis skin was closed. In TRANSECTED group left sciatic nerve was transected and stumps were fixed in adjacent muscle. In CHITOSAN and CSBNC groups, 10-mm sciatic nerve defects were bridged using a chitosan and chitosan-selenium biodegradable nanocomposite conduits, respectively. The regenerated fibers were studied 4, 8 and 12 weeks after surgery. Assessment of nerve regeneration was based on behavioral, functional, biomechanical, histomorphometric and immunohistochemical criteria. Results : The behavioral, functional and biomechanical studies confirmed significant recovery of regenerated axons in CSBNC group ( P < 0.05). Quantitative morphometric analyses of regenerated fibers showed the number and diameter of myelinated fibers in CSBNC group were significantly higher than in the CHITOSAN group ( P < 0.05). Discussion : This demonstrates the potential of using CSBNC in peripheral nerve regeneration without limitations of donor-site morbidity associated with isolation autograft. It is also cost saving and may have clinical implications for the surgical management of patients after facial nerve transection.