Nerve Conduit With Autologous Tissue Promotes Peripheral Nerve Regeneration In Rodent Model

PART1 Epimysium-muscle conduit with live myogenic cells promotes peripheral nerve regeneration in rodent modelObjective:Epimysium-muscle conduit(EMC)was reported to be an alternative repair method for promoting sciatic nerve regeneration.Furthermore,the myogenic cells inside the epimysium nerve conduit include skeletal muscle-derived stem cells,which may contribute to the improvement of nerve regeneration.However,how epimysium-muscle conduit promotes nerve regeneration still needs to be understood.Methods:Proper methods were examined to inhibit or destroy function and proliferation of myogenic cells in epimysium-muscle conduit in vitro.Then,three groups,a normal EMC group,irradiated EMC(IR-EMC)group and decellularized EMC(DE-EMC)group,were prepared to repair mice 5 mm long sciatic nerve defects in mice in order to investigate the effect of live myogenic cells.At 8 and 12 weeks post-operation,immunofluorescence staining and transmission electron microscopy were used for assessing the regenerated nerve tissue.The walking-track analysis,wet weight analysis and Masson trichrome staining of gastrocnemius muscles were performed to evaluate recovery of nerve function.Result:The results showed that 8 and 12 weeks after surgery,the EMC group was significantly superior to the IR-EMC and DE-EMC groups in gross appearance,uniform distribution of axonal myelin sheath,number of myelinated nerve fibers and reversal of muscle atrophy.The myogenic cells from skeletal muscle may migrate inward and differentiate into Schwann cells under certain injured-nerve microenvironment.Conclusion:Epimysium nerve conduit with the presence of live myogenic cells effectively promoted axon and myelin sheath regeneration,which makes it a promising future candidate for nerve repair.PART 2 Platelet-rich fibrin membrane nerve guidance conduit(PRF-NGC),a potential promising method for peripheral nerve injuriesBackground:Platelet Rich Fibrin(PRF)is defined as new generation of platelet concentrates on fibrin gel with high regenerative potential.However,PRF membrane served as a nerve conduit has not yet been studied.The aim of our study was thus to investigate the potential effect of PRF-NGC on peripheral nerve repair.Methods:A total of 24 BALB/c nude mice were examined,8 mice received the PRF-NGC treatment,8 mice received autologous nerve grafting which served as positive control group and the remaining 8 mice formed the polyurethane(PUR)conduits negative control group.PRF was isolated from Sprague-Dawley(SD)rats.Regenerated nerves were analyzed by immunofluorescent staining and transmission electron microscopy.Measurements of wet weight and Masson's trichrome stained sections of gastrocnemius muscle were collected for deterministic quantification of sciatic nerve functional recovery.Results:12 weeks post-surgery,the measures of regeneration of myelinated axon numbers,nerve fiber diameter,thickness of the myelin sheath,and of gastrocnemius muscle atrophy recovery for the PRF-NGC group were significantly better than were found for the PUR group.While the nerve fiber diameter,maturity of myelin sheath and muscle recovery in the PRF group were not found to have been significantly worse than were found for the ANG group.Conclusions:The novel findings identified that PRF-NGC promoted nerve regeneration and may help clinical surgeons treat seriously injured cases in a rapid fashion.