Nano artificial periosteum PLGA/MgO/Quercetin accelerates repair of bone defects through promoting osteogenic - angiogenic coupling effect via Wnt/ β-catenin pathway.

Bone nonunion or delayed union, caused by stripping or injuring of periosteum, is the most common sequelae of segmental bone defects. The preservation of periosteum, or the use of periosteal grafts, can significantly improve the integration of bone graft, speeding up the process of bone reconstruction. However, in most cases, periosteum cannot be preserved with bioactivity. Thus, it is pivotal to develop artificial periosteum. In this study, artificial periosteum of PLGA/MgO/Quercetin was prepared by electrospinning. PLGA/MgO/Quercetin membranes were shown to have a highly porous surface and microstructure, as observed by scanning electron microscopy. Along with excellent biocompatibility, PLGA/MgO/Quercetin membranes promoted cell proliferation and migration, as well as osteogenic differentiation of BMSCs (Bone marrow mesenchymal stem cells) in a dose-dependent manner through the activation of Wnt/β-Catenin pathway. The PLGA/MgO/Quercetin membranes, with an appropriate concentration of quercetin (<1 ​wt%), promoted EPCs (Endothelial progenitor cells) angiogenesis. In a subcutaneous implantation model and rat skull defect model, optimal osteogenesis and angiogenesis function were observed for the PLGA/20 ​wt% MgO/0.1 ​wt% Quercetin membrane. In conclusion, PLGA/MgO membranes, with an appropriate concentration of quercetin, show a variety of biological activities and are promising materials for the generation of artificial periosteum.