血管内皮生长因子与纳米晶胶原基骨支架复合修复大鼠股骨缺损

背景：研究证实纳米晶胶原基骨复合间充质干细胞修复骨缺损具有体内成骨能力。 目的：观察血管内皮生长因子与骨髓间充质干细胞、纳米晶胶原基骨复合物修复大鼠股骨缺损的效果。 方法：制作SD大鼠股骨中段骨缺损模型，随机分为2组：对照组植入骨髓间充质干细胞/纳米晶胶原基骨复合物；实验组植入血管内皮生长因子/骨髓间充质干细胞/纳米晶胶原基骨复合物。术后第2，4，8周行股骨标本影像学与组织学观察；术后第8周行新生骨痂环境扫描电镜检查。 结果与结论：纳米晶胶原基骨支架复合物植入大鼠体内后无排斥反应及炎症反应，且血管内皮生长因子/骨髓间充质干细胞/纳米晶胶原基骨复合物成骨更快，较骨髓间充质干细胞/纳米晶胶原基骨复合物具有更好的骨再生能力，其成骨方式主要为软骨内成骨。推测血管内皮生长因子促进了局部微血管的形成和成骨细胞的分化、增殖，加快了软骨内成骨的速率，缩短了骨修复时间，提高了骨再生的质量和速率。

Vascular endothelial growth factor and nano-hydroxyapatite/collagen composite in the repair of femoral defect in rats

BACKGROUND: Previous studies have confirmed that nano-hydroxyapatite/collagen (nHAC) and mesenchymal stem cells for repair of bone defect have the ability of bone formation in vivo. OBJECTIVE: To observe the effects of vascular endothelial growth factor (VEGF) and bone marrow mesenchymal stem cells (BMSCs), nHAC composite in the repair of femoral defect in rats. METHODS: Sprague-Dawley rat models of middle part of the femur defect were established and randomly assigned to two groups. Control group was implanted with BMSCs/nHAC composite. Experimental group was implanted with VEGF/BMSCs/nHAC composite. At 2, 4 and 8 weeks postoperation, imaging and histology observation of femoral samples were performed. At 8 weeks postoperation, scanning electron microscopy was performed in new bony callus environment. RESULTS AND CONCLUSION: nHAC composite implantation in the rats did not show rejection or inflammatory reaction. Moreover, bone formed rapidly using VEGF and BMSCs, nHAC composite, which exhibited better bone regeneration capacity compared with BMSCs/nHAC composite. The way of ossification mainly was endochondral ossification. It is presumed that VEGF promoted the formation of local microvessels, differentiation and proliferation of osteoblasts, speeded up the speed of endochondral ossification, shortened bone repair time, and elevated the quality and velocity of osteanagenesis.