Sustained Delivery of BMP-2-Related Peptide from the True Bone Ceramics/Hollow Mesoporous Silica Nanoparticles Scaffold for Bone Tissue Regeneration

Abstract

Bone morphogenetic protein 2 (BMP-2) is one of the most important factors for bone tissue formation. A number of BMP-2 related small molecule bioactive peptides have been designed and shown to be equally effective in osteogenic activity. In this report, we synthesized a novel BMP-2-related peptide (designated P28) and designed a delivery system to regulate the controlled release of P28 from true bone ceramics (TBC) combined with an enlarged pore hollow mesoporous silica nanoparticles (HMSNs) composite scaffold. An <i>in vitro</i> release showed that the release of P28 from the TBC/HMSN scaffold was slower than that from the TBC scaffold. An <i>in vitro</i> cell experiment of the TBC/HMSN/P28 scaffold was tested with MC3T3-E1 cells in comparison to TBC, TBC/HMSN, and TBC/P28 scaffolds. Our results demonstrated that the TBC/HMSN/P28 scaffold had better effects on promoting proliferation and osteogenic differentiation of MC3T3-E1 cells than TBC, TBC/HMSN, and TBC/P28 scaffolds. After four kinds of scaffolds were implanted into a rabbit radius critical bone defect for 6 and 12 weeks, the radiographic and histological examination indicated that this osteogenic delivery system TBC/HMSN/P28 scaffold effectively induced bone regeneration <i>in vivo</i>. Therefore, the TBC/HMSN/P28 scaffold can promote proliferation and osteogenic differentiation of MC3T3-E1 cells <i>in vitro</i> and new bone tissue generation <i>in vivo</i>. This study provides a promising scaffold for bone tissue engineering and regenerative medicine.