State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China.
Department of Anesthesiology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, 121000, China.
Biomater Adv. 2024 Nov;164:213977. doi: 10.1016/j.bioadv.2024.213977. Epub 2024 Jul 30.
Biodegradable polymer microspheres in bone tissue engineering have become appealing as their non-invasive advantages in irregular damage bone repair. However, current microspheres used in BTE still lack sufficient osteogenic capacity to induce effective bone regeneration. In this study, we developed osteogenic composite microspheres concurrently loaded with magnesium oxide (MgO) and zinc oxide (ZnO), both of which are osteogenic active substances, using a facile and scalable emulsification method. The osteogenic composite microspheres exhibited a sequential yet complementary release profile characterized by a rapid release of Mg and a gradual release of Zn in a physiological environment, thereby maintaining the concentration of bioactive ions at a sustained high level. As a result, the combination of Mg and Zn in the composite microspheres led to a synergistic enhancement in biomimetic mineralization and the upregulation in the expression of osteogenic-related genes and proteins at the cellular level. Through a critical-sized calvarial rate defect model, the osteogenic composite microspheres were demonstrated to have strong osteogenic ability to promote new bone formation via ultrasonic imaging, histological and immunohistochemical evaluations. In sum, these osteogenic composite microspheres as microcarriers of Mg and Zn have great potential in the delivery of therapeutic ions for treating bone defects.
在不规则损伤性骨修复中，具有非侵入性优势的可生物降解聚合物微球已成为骨组织工程中的热门研究对象。然而，目前用于 BTE 的微球仍然缺乏足够的成骨能力来诱导有效的骨再生。在本研究中，我们使用简单且可扩展的乳化方法，开发了同时负载具有成骨活性的氧化镁（MgO）和氧化锌（ZnO）的成骨复合微球。成骨复合微球表现出顺序但互补的释放特性，即在生理环境中快速释放 Mg 和缓慢释放 Zn，从而使生物活性离子的浓度保持在持续高水平。结果，复合微球中 Mg 和 Zn 的组合导致仿生矿化的协同增强，以及细胞水平上成骨相关基因和蛋白的表达上调。通过临界尺寸颅骨缺损模型，通过超声成像、组织学和免疫组织化学评估，证明成骨复合微球具有很强的成骨能力，可促进新骨形成。总之，这些作为 Mg 和 Zn 治疗离子载体的成骨复合微球在治疗骨缺损方面具有很大的潜力。
