高仿真壳聚糖支架修复神经缺损的有效性研究

Efficacy of biomimicking chitosan scaffolds in bridging large nerve defect

[目的]构建具有仿真结构的壳聚糖神经支架,评价其在体桥接大鼠15mm坐骨神经缺损的修复效果。[方法]应用自主研发的梯度冷冻干燥技术,制备具有仿真结构的壳聚糖神经支架。将该仿真支架修复大鼠15mm坐骨神经缺损,应用形态计量学、逆行示踪、神经电生理以及行为学检测评价该仿真支架的修复效果。[结果]本实验构建的壳聚糖支架具有轴向平行排列的微管样超微结构,该结构高度仿真于正常神经基底膜结构。在修复大鼠15mm坐骨神经缺损的实验中,该仿真支架可取得与自体神经移植相似的修复效果。[结论]高仿真壳聚糖神经支架具有与正常神经高度仿真的内部结构,在体修复效果好,有望成为自体神经移植的替代产品。

[Objective] To develop biomimicking chitosan scaffolds with longitudinally oriented micro-channels,and investigate their efficacy in bridging 15 mm sciatic nerve gap in rats.[Methods]Chitosan scaffolds with longitudinally oriented micro-channels were fabricated using unidirectional freezing-dry methods.The chitosan scaffolds were used to bridge 15 mm nerve defect in rats,and their efficacy in bridging nerve gap was evaluated by morphometric analysis,retrograde labeling,electrophysiological studies and behavioral analysis.[Results]The chitosan scaffolds developed in the present study showed longitudinally oriented micro-channels,which resembled the dimensions of basal lamina channels in normal nerves.Implantation of chitosan scaffold achieved axonal regeneration and functional recovery similar to autograft implantation in vivo.[Conclusion]The chitosan scaffolds have inner microstructures which resemble the basal lamina channels in normal nerves.The chitosan scaffold may be used as an alternative to autograft in bridging nerve gaps.