State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, People's Republic of China.
Center of Craniofacial Orthodontics, Department of Oral and Cranio-maxillofacial Science, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai 200011, People's Republic of China.
ACS Appl Mater Interfaces. 2016 May 11;8(18):11342-54. doi: 10.1021/acsami.6b03100. Epub 2016 Apr 29.
Bone tissue engineering offers a possible strategy for regenerating large bone defects, in which how to design beneficial scaffolds for accelerating bone formation remains significantly challenging. Europium, as an important rare earth element, has been used as a solid-state lighting material. However, there are few reports on whether Eu can be used for labeling bone tissue engineering scaffolds, and its biological effect on bone cells and bone tissue regeneration is unknown. In this study, we incorporated Eu into mesoporous bioactive glass (Eu-MBG) scaffolds by an in situ cotemplate method to achieve a bifunctional biomaterial with biolabeling and bone regeneration. The prepared Eu-MBG scaffolds have highly interconnective large pores (300-500 μm), a high specific surface area (140-290 m(2)/g), and well-ordered mesopores (5 nm) as well as uniformly distributed Eu. The incorporation of 2-5 mol % Eu into MBG scaffolds gives them a luminescent property. The in vitro degradation of Eu-MBG scaffolds has a functional effect on the change of the luminescence intensity. In addition, Eu-MBG can be used for labeling bone marrow stromal cells (BMSCs) in vitro and still presents a distinct luminescence signal in deep bone tissues in vivo to label new bone tissue via release of Eu ions. Furthermore, the incorporation of different contents of Eu (1, 2, and 5 mol %) into MBG scaffolds significantly enhances the osteogenic gene expression of BMSCs in the scaffolds. The Eu- and Si-containing ionic products released from Eu-MBG scaffolds distinctly promote the osteogenic differentiation of BMSCs. Critically sized femur defects in ovariectomized (OVX) rats are created to simulate an osteoporotic phenotype. The results show that Eu-MBG scaffolds significantly stimulate new bone formation in osteoporotic bone defects when compared to MBG scaffolds alone and Eu may be involved in the acceleration of bone regeneration in OVX rats. Our study for the first time reports that the incorporation of the rare earth element Eu into bioscaffolds has the ability to accelerate bone regeneration in vivo, and thus, the prepared Eu-MBG scaffolds possess bifunctional properties with biolabeling and bone regeneration.
骨组织工程为再生大的骨缺损提供了一种可能的策略，其中如何设计有利于骨形成的支架仍然是一个巨大的挑战。铕作为一种重要的稀土元素，已被用作固态照明材料。然而，关于铕是否可用于标记骨组织工程支架，以及它对骨细胞和骨组织再生的生物学效应知之甚少。在本研究中，我们通过原位共模板法将铕掺入介孔生物活性玻璃（Eu-MBG）支架中，以获得具有生物标记和骨再生双重功能的生物材料。所制备的 Eu-MBG 支架具有高度互连的大孔（300-500μm）、高比表面积（140-290m2/g）和有序介孔（5nm）以及均匀分布的 Eu。将 2-5mol%的 Eu 掺入 MBG 支架中可赋予其发光性能。Eu-MBG 支架的体外降解对发光强度的变化具有功能作用。此外，Eu-MBG 可用于体外标记骨髓基质细胞（BMSCs），并且在体内深部骨组织中仍呈现出明显的发光信号，通过释放 Eu 离子来标记新的骨组织。此外，将不同含量的 Eu（1、2 和 5mol%）掺入 MBG 支架中可显著增强支架中 BMSCs 的成骨基因表达。Eu-MBG 支架中释放的含 Eu 和 Si 的离子产物明显促进了 BMSCs 的成骨分化。在去卵巢（OVX）大鼠中建立临界尺寸股骨缺损以模拟骨质疏松表型。结果表明，与单独使用 MBG 支架相比，Eu-MBG 支架可显著促进骨质疏松性骨缺损中的新骨形成，并且 Eu 可能参与了 OVX 大鼠中骨再生的加速。我们的研究首次报道，将稀土元素 Eu 掺入生物支架中具有在体内加速骨再生的能力，因此，所制备的 Eu-MBG 支架具有生物标记和骨再生的双重功能。
