Controlled delivery of glial cell line-derived neurotrophic factor enhances motor nerve regeneration / 中国医师杂志

ABSTRACT

Objective@#To determine the effect of a motor-specific neurotrophic factor, glial-derived neurotrophic factor (GDNF) on motor nerve regeneration.@*Methods@#We used a nerve conduit filled with a fibrin-based delivery system that provided controlled release of GDNF during nerve regeneration. The motor branch of the rat femoral nerve was used to assess motor nerve regeneration across a 5-mm gap. Four experimental groups (n=5) were evaluated. These included GDNF with the fibrin-based delivery system (GDNF-DS group), fibrin alone(fibrin group), empty conduit (negative control group), and nerve isograft (positive control group). Nerves were harvested at 5 weeks for analysis by histomorphometry and electron microscopy.@*Results@#At 5 mm distal to the conduit or isografts, the GDNF-DS group was not significantly different from the nerve isograft group in the following histomorphometric measures: total nerve fibers, percentage of neural tissue, and nerve density. The number of nerve fibers (respectively 1 744±274 , 1 481±288) and the percentage of nerve tissue [(14.2±3.9)%, (11.0±2.2)%] in theisograft group and the GDNF-DS group were significantly higher than that in the fibrin group and the empty conduit group [(respectively 538±93, 535±96) and the percentage of nerve tissue respectively (4.3±1.6)%, (3.7±0.9)%]. There were no differences in fiber width among all groups. By electron microscopy, the GDNF-DS and isograft groups also demonstrated more organized nerve architecture than the fibrin alone and empty conduit groups.@*Conclusions@#The delivery of GDNF from the fibrin-based delivery system promotes motor nerve regeneration at a level similar to an isograft in the femoral motor nerve model. This study gives insight into the potential beneficial role of GDNF in the treatment of motor nerve injuries.