纳微多孔结构骨植入材料缓释染料木素促进脊椎间骨融合及机制

It is necessary to treat pain of neck/waist and numbness of limb caused by spinal degenerative disease via surgical operation (spine intervertebral fusion) if the spinal cord or nerve root are compressed.Bone implant materials is key to the success of this surgical operation by promoting spine intervertebral fusion. Bone implant composite with nano-micro structure and containing mesoporous magnesium based bioglass and poly(ether-ether-ketone) for loading and delayed-release genistein (drug) was designed and developed, which were used to promote spine intervertebral fusion. The effects and regulation of composition/structure of the drug loaded bone implant composite on their mechanical performances,bioactivity and drug delayed release were studied. The effects and mechanism of composition/structure (surface morphology, chemical performances, drug delayed release) of the drug loaded bone implant composite on bone marrow mesenchymal stem cells behaviours (cell adhesion, proliferation and differentiation, and bone interrelated gene expression) were studied by cell culture. The impact of stimulating new bone regeneration and promoting spine intervertebral fusion of the drug loaded bone implant composite were studied by implantation in vivo through animal model (sheep spine intervertebral fusion), and mechanism of promoting bone fusion of the drug loaded bone implant materials was opened out. Biosecurity, biocompatibility and functionality of the drug loaded bone implant composite were entirely evaluated in this study. The relationship between composition/structure and functions (stimulation new bone regerenation, promotion bone fusion) of drug loaded bone implant composite were elucidated, which will provide new method for developing new implantable material of spine intervertebral fusion with special biofunction, and provide based gist for clinical application.

由脊柱退行性病变引起的严重颈/腰痛及肢体麻木发展为脊髓/神经根压迫，需要手术治疗（脊柱融合术），而骨植入材料促进脊椎间骨融合是该手术成功的关键。本研究设计基于纳微孔结构的介孔镁基玻璃与聚醚醚酮复合多孔骨植入材料，负载和缓释染料木素（药物），用于促进脊椎间骨融合。研究载药多孔骨植入材料的组成结构对其力学性能、生物活性、药物缓释等性能的影响及调控。研究载药多孔材料的组成结构（如表面微纳形貌、化学特性和药物缓释等）对骨髓基质干细胞行为如粘附、增殖与分化、基因表达等的影响及机制。将载药多孔材料植入动物体内（羊脊柱模型），研究其刺激新骨再生，促进骨融合的效果，并揭示其机制。通过研究，全面评价载药多孔骨植入材料的安全性、生物相容性及功能性，阐明载药骨植入材料的组成结构与功能（刺激新骨再生，促进骨融合）的关系，为发展新型、有特殊功能的脊椎间融合骨植入材料提供新思路和新技术，为其临床应用提供依据。

本项目设计基于纳微孔结构的介孔镁基玻璃与聚醚醚酮复合多孔骨植入材料，负载和缓释染料木素（GS），用于促进骨融合。合成了介孔镁基生物玻璃（m-MCS），采用冷压烧结技术制备了m-MCS/PEEK复合材料，并通过颗粒浸出、喷砂、磺化技术对复合材料进行改性。该复合多孔材料具有高亲水性和表面粗糙度，高孔隙率和吸水性。在模拟体液中，复合多孔材料可以显著促进磷灰石矿化，表现出优异的体外生物活性；且随着复合多孔材料中m-MCS含量的提高，其体外生物活性随之提高。抗菌实验表明，磺化复合多孔材料明显抑制了金黄色葡萄球菌和大肠杆菌的生长，表明表面上引入的磺酸根基团（-SO3H）具有优异的抗菌活性。体外细胞实验发现复合多孔材料可以促进鼠前成骨细胞（MC3T3-E1）和大鼠骨髓间充质干细胞（rBMSCs）的粘附、增殖与分化。体内动物实验发现复合多孔材料可以促进新骨再生，并与周围骨组织形成良好的骨整合。血管内皮生长因子（VEGF）免疫组织化学评价表明：复合多孔材料可以促进VEGF阳性表达，具有促血管生成的潜力。将复合多孔材料在磷酸缓冲溶液（PBS）中负载并缓释GS，发现GS可以缓慢并持续从复合多孔材料表面释放出来。抗菌实验表明，负载GS的复合多孔材料缓释GS明显抑制了金黄色葡萄球菌和大肠杆菌的生长，具有优异的抗菌活性。体外细胞实验发现载药复合多孔材料可以促进MC3T3-E1和rBMSCs的粘附、增殖与分化，以及成骨相关基因的表达，具有良好的体外细胞相容性。体内动物实验发现载药复合多孔材料可以显著促进新骨在植入体周围的生成，与植入体形成良好的骨融合。通过研究，评价了载药多孔骨植入材料的安全性、生物相容性及功能性，阐明载药骨植入材料的组成结构与功能（刺激新骨再生，促进骨融合）的关系，将为发展新型、有特殊功能的骨融合植入材料提供新思路和新技术，为其临床应用提供依据。