Neural stem cells enhance nerve regeneration after sciatic nerve injury in rats

摘要

With the development of tissue engineering and the shortage of autologous nerve grafts in nerve reconstruction, cell transplantation in a conduit is an alternative strategy to improve nerve regeneration. The present study evaluated the effects and mechanismofbrain-derived neural stemcells (NSCs) onsciatic nerve injury in rats. At the transection of the sciatic nerve, a 10-mm gap between the nerve stumps was bridged with a silicon conduit filledwith5×105NSCs. Incontrol experiments, the conduitwas filledwithnerve growth factor(NGF)ornormal saline (NS). The functional and morphological properties of regenerated nerves were investigated, and expression of hepatocyte growth factor (HGF) andNGFwasmeasured.Oneweek later, therewas noconnectionthrough the conduit.Four or eight weeks later, fibrous connections were evident between the proximal and distal segments. Motor function was revealed by measurement of the sciatic functional index (SFI) and sciatic nerve conduction velocity (NCV). Functional recovery in the NSC and NGF groups was significantly more advanced than that in theNS group.NSCs showed significant improvement in axonmyelinationof the regeneratednerves.Expression ofNGF and HGF in the injured sciatic nerve was significantly lower in the NS group than in the NSCs and NGF groups. These results and other advantages of NSCs, such as ease of harvest and relative abundance, suggest thatNSCs could be used clinically to enhance peripheral nerve repair.