Controlling sustained statins release in multi-layered composite scaffolds for healing of osteoporotic bone defects

The risk of fragility fracture sharply increases due to the decreased bone mineral density and toughness in patients with osteoporosis (OP). The local use of bone tissue scaffolds with both mechanical stability and drug-delivery functionality is one of the key strategies for the efficient curing of OP. In this work, we reported a layer-by-layer constructing strategy to fabricate 3-D composite bone tissue scaffolds (eSTPS) by assembling β-tri‑calcium phosphate (β-TCP)/polycaprolactone (PCL) microchips and lovastatin-loaded nanofiber membranes (eLOV/PCL). The eSTPS scaffolds show a strong and suited compressive strength as well as long-term delivery of lovastatin. The in vitro tests indicate well biocompatibility and alkaline phosphatase activity of the scaffolds. The eSTPS scaffolds were implanted into the femur of OP modeled rabbits. After 12 weeks curing, the bone parameters are significantly improved, meanwhile ingrowth of new bone and vascular-like tissue were observed. These results suggest the eSTPS scaffolds to be a promising candidate for the local treatment of OP.