Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People's Republic of China.
Biomaterials. 2011 Oct;32(29):7068-78. doi: 10.1016/j.biomaterials.2011.06.009. Epub 2011 Jun 24.
Boron is one of the trace elements in the human body which plays an important role in bone growth. Porous mesopore bioactive glass (MBG) scaffolds are proposed as potential bone regeneration materials due to their excellent bioactivity and drug-delivery ability. The aims of the present study were to develop boron-containing MBG (B-MBG) scaffolds by sol-gel method and to evaluate the effect of boron on the physiochemistry of B-MBG scaffolds and the response of osteoblasts to these scaffolds. Furthermore, the effect of dexamethasone (DEX) delivery in B-MBG scaffold system was investigated on the proliferation, differentiation and bone-related gene expression of osteoblasts. The composition, microstructure and mesopore properties (specific surface area, nano-pore volume and nano-pore distribution) of B-MBG scaffolds have been characterized. The effect of boron contents and large-pore porosity on the loading and release of DEX in B-MBG scaffolds were also investigated. The results have shown that the incorporation of boron into MBG scaffolds slightly decreases the specific surface area and pore volume, but maintains well-ordered mesopore structure and high surface area and nano-pore volume compared to non-mesopore bioactive glass. Boron contents in MBG scaffolds did not influence the nano-pore size distribution or the loading and release of DEX. B-MBG scaffolds have the ability to maintain a sustained release of DEX in a long-term span. Incorporating boron into MBG glass scaffolds led to a controllable release of boron ions and significantly improved the proliferation and bone-related gene expression (Col I and Runx2) of osteoblasts. Furthermore, the sustained release of DEX from B-MBG scaffolds significantly enhanced alkaline phosphatase (ALP) activity and gene expressions (Col I, Runx2, ALP and BSP) of osteoblasts. These results suggest that boron plays an important role in enhancing osteoblast proliferation in B-MBG scaffold system and DEX-loaded B-MBG scaffolds show great potential as a release system to enhance osteogenic property for bone tissue engineering application.
硼是人体中的微量元素之一，在骨骼生长中起着重要作用。多孔中孔生物活性玻璃（MBG）支架因其具有优异的生物活性和药物输送能力而被提议作为潜在的骨再生材料。本研究旨在通过溶胶-凝胶法制备含硼 MBG（B-MBG）支架，并评估硼对 B-MBG 支架理化性质和成骨细胞对这些支架反应的影响。此外，还研究了在 B-MBG 支架系统中递送地塞米松（DEX）对成骨细胞增殖、分化和骨相关基因表达的影响。B-MBG 支架的组成、微观结构和中孔性质（比表面积、纳米孔体积和纳米孔分布）已得到表征。还研究了硼含量和大孔孔隙率对 B-MBG 支架中 DEX 的负载和释放的影响。结果表明，硼的掺入使 MBG 支架的比表面积和孔体积略有降低，但与非中孔生物活性玻璃相比，仍保持有序的中孔结构和高的比表面积和纳米孔体积。硼含量对 MBG 支架的纳米孔尺寸分布或 DEX 的负载和释放没有影响。B-MBG 支架具有在较长时间内维持 DEX 持续释放的能力。将硼掺入 MBG 玻璃支架中可控制释放硼离子，并显著提高成骨细胞的增殖和骨相关基因表达（Col I 和 Runx2）。此外，B-MBG 支架中 DEX 的持续释放显著增强了碱性磷酸酶（ALP）活性和成骨细胞的基因表达（Col I、Runx2、ALP 和 BSP）。这些结果表明，硼在增强 B-MBG 支架系统中成骨细胞增殖方面起着重要作用，负载 DEX 的 B-MBG 支架作为一种释放系统，具有增强骨组织工程应用中成骨特性的巨大潜力。
