Synergistic effect of electrophysiological microenvironment and bioactive ions for enhancing bone regeneration

Bone traumatic defects, requiring a long-term healing procedure cause the destruction of physical microenvironment, remain a critical challenge in orthopedic care. Given the electrical properties and bioactive elemental composition of natural bone, electrophysical microenvironment and bioactive ions play crucial roles in regulating bone metabolism. Our study constructs an implantable electret scaffold based on coaxial electrospinning technology. The core-shell electrospun fibrous membrane (PSPC) comprising shell structure of polycaprolactone (PCL)/calcium silicate nanowires (CSNs) loading with a core of polycaprolactone/silicon dioxide (SiO2) electret. In which, the sheath of the core-shell fibers is designed to continuously release bioactive ions to stimulate osteogenesis after the fiber degrades, while the core layer is intended to provide consistent endogenous electrical stimulation for osteogenic differentiation. This battery-free and biocompatible scaffold utilizes the synergistic outcome of electrical stimulation and bioactive ions and shows the most satisfactory osteogenic efficiency both in vitro and in vivo. Moreover, the underlying mechanism was interpreted that electrical stimulation-driven osteogenesis was driven by the activation of Calmodulin (CaM) / Calcineurin (CaN)/nuclear factor of activated T cells (NFAT) signaling pathway. This work proposes a potential strategy to improve bone regeneration by developing a coaxial electrospun fibrous membrane that combines the synergistic benefits of electrophysical microenvironment restoration and bioactive ions.