The effects of gradients of nerve growth factor immobilized PCLA scaffolds on neurite outgrowth in?vitro and peripheral nerve regeneration in rats

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• 作者：Shuo Tang ; Jixiang Zhu ; Yangbin Xu ; Andy Peng Xiang ; Mei Hua Jiang ; Daping Quan
• 关键词：Nerve regeneration ; Nerve conduit ; Nanofibrous architecture ; Gradient ; Nerve growth factor
• 刊名：Biomaterials
• 出版年：2013
• 出版时间：September, 2013
• 年：2013
• 卷：34
• 期：29
• 页码：7086-7096
• 全文大小：7384 K

文摘

Introducing concentration gradients of nerve growth factor (NGF) into conduits for repairing of peripheral nerve injury is crucial for nerve regeneration and guidance. Herein, combining differential adsorption of NGF/silk fibroin (SF) coating, the gradient of NGF-immobilized membranes (G-Ms) and nanofibrous nerve conduits (G-nNCs) were successfully fabricated. The efficacy of NGF gradients was confirmed by a quantitative comparison of dorsal root ganglia (DRG) neurite outgrowth on the G-Ms or uniform NGF-immobilized membranes (U-Ms). Significantly, the neurite turning ratio was 0.48?¡À?0.11 for G-M group, but it was close to zero for U-M group. The neurite length of DRGs in the middle of the G-Ms was significantly longer than that of U-M group, even though the average NGF concentration was approximated. Furthermore, 12 weeks after implantation in rats with a 14?mm gap of sciatic nerve injury, G-nNCs achieved satisfying outcomes of nerve regeneration associated with morphological and functional improvements, which was superior to that of the uniform NGF-immobilized nNCs (U-nNCs). Sciatic function index (SFI), compound muscle action potentials (CMAPs), total number of myelinated nerve fibers, thickness of myelin sheath were similar for the G-nNCs and autografts, with the G-nNCs having a higher density of axons than the autografts. Our results demonstrated the significant role of introducing NGF gradients into scaffolds in promoting nerve regeneration.