The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234, China.
Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China.
Carbohydr Polym. 2022 Sep 1;291:119575. doi: 10.1016/j.carbpol.2022.119575. Epub 2022 May 6.
Nacre, exhibiting excellent mechanical strengths due to its hierarchical structures, becomes a potential model to design bone implants. Herein, we firstly fabricated nacre-mimetic hydroxyapatite/chitosan/gelatin (HA/CS/Gel) layered scaffolds and incorporated substance P (SP) peptides. The CS scaffolds with a layered architecture could regulate the deposition of HA nanoplates on the interlamellar CS sheets by using CaCO as precursors. The HA/CS/Gel layered scaffolds exhibited a great flexure strength of 11.42 MPa due to a brick-and-mortar structure. The biocompatible components, layered macropores and SP peptides in the HA/CS/Gel therapeutic scaffolds facilitated the spreading and proliferation mesenchymal stem cells (MSCs). Notably, the incorporation of SP peptides induced MSC osteogenic differentiation and extracellular matrix mineralization. Rabbit knee subchondral defect models further proved that the HA/CS/Gel-SP layered scaffolds promoted in vivo subchondral bone regeneration. Hence, the combination of nacre-mimetic bone implants and therapeutic drugs may become an attractive strategy for subchondral bone regeneration.
珍珠层由于其分层结构而表现出优异的机械强度，成为设计骨植入物的潜在模型。在此，我们首先制备了珍珠层仿生羟基磷灰石/壳聚糖/明胶（HA/CS/Gel）分层支架并掺入了 P 物质（SP）肽。CS 支架具有分层结构，可以通过使用 CaCO 作为前体来调节 HA 纳米板在层间 CS 片上的沉积。由于具有“砖-泥”结构，HA/CS/Gel 分层支架表现出 11.42 MPa 的高弯曲强度。HA/CS/Gel 治疗性支架中的生物相容性成分、分层大孔和 SP 肽促进了间充质干细胞（MSCs）的扩展和增殖。值得注意的是，SP 肽的掺入诱导 MSC 成骨分化和细胞外基质矿化。兔膝关节软骨下缺损模型进一步证明，HA/CS/Gel-SP 分层支架促进了体内软骨下骨再生。因此，珍珠层仿生骨植入物和治疗药物的结合可能成为软骨下骨再生的一种有吸引力的策略。
