Strontium Peroxide-Loaded Composite Scaffolds Capable of Generating Oxygen and Modulating Behaviors of Osteoblasts and Osteoclasts

Abstract

The reconstruction of bone defects remains challenging. The utilization of bone autografts, although quite promising, is limited by several drawbacks, especially substantial donor site complications. Recently, strontium (Sr), a bioactive trace element with excellent osteoinductive, osteoconductive, and pro-angiogenic properties, has emerged as a potential therapeutic agent for bone repair. Herein, a strontium peroxide (SrO2)-loaded poly(lactic-co-glycolic acid) (PLGA)-gelatin scaffold system was developed as an implantable bone substitute. Gelatin sponges serve as porous osteoconductive scaffolds, while PLGA not only reinforces the mechanical strength of the gelatin but also controls the rate of water infiltration. The encapsulated SrO2 can release Sr2+ in a sustained manner upon exposure to water, thus effectively stimulating the proliferation of osteoblasts and suppressing the formation of osteoclasts. Moreover, SrO2 can generate hydrogen peroxide and subsequent oxygen molecules to increase local oxygen tension, an essential niche factor for osteogenesis. Collectively, the developed SrO2-loaded composite scaffold shows promise as a multifunctional bioactive bone graft for bone tissue engineering.

Recent Advance of Strontium Functionalized in Biomaterials for Bone Regeneration

“…Han et al [ 105 ] prepared mineralized electrostatic spun poly (lactic acid) nanofiber membranes containing varying amounts of Sr, and the membrane promoted BMSC proliferation and osteogenic differentiation, and in vivo bone defect experiments also proved that the membrane could promote bone regeneration. Lin et al [ 106 ] developed a Sr peroxide (SrO 2 )-loaded poly (lactic-co-glycolic acid) (PLGA)-gelatin scaffold system. This system effectively stimulated osteoblast proliferation and inhibited osteoclast formation.…”

Functional β‐TCP/MnO2/PCL artificial periosteum promoting osteogenic differentiation of BMSCs by reducing locally reactive oxygen species level

“…31 SrO 2 loaded PLGA-gelatin scaffold was reported to promote fracture repair through releasing O 2 locally and regulating the behavior of osteoblasts and osteoclasts. 32 β-TCP/MnO 2 /PCL artificial periosteum we constructed in this study has superior biocompatibility and cell adhesion.…”

“…PLGA/CaO 2 /MnO 2 nanoparticles had been proved to release oxygen locally and relieve local hypoxia tension, thus, promote new bone formation and fracture healing through enhancing the osteogenesis of osteoblasts and their mineral deposition in vitro 31 . SrO 2 loaded PLGA‐gelatin scaffold was reported to promote fracture repair through releasing O 2 locally and regulating the behavior of osteoblasts and osteoclasts 32 . β‐TCP/MnO 2 /PCL artificial periosteum we constructed in this study has superior biocompatibility and cell adhesion.…”

Core-shell oxygen-releasing fibers for annulus fibrosus repair in the intervertebral disc of rats

“…In the early stage of tissue injury, hypoxia is unfavorable for tissue regeneration, especially in a poorly vascularized microenvironment, which generally induces oxidative stress, apoptosis and necrosis, thereby accelerating cell death [ 46 ]. In recent years, the issue of local hypoxia in skin healing, bone regeneration and nerve repair has gained increasing attention, and studies have clarified the beneficial effects of local oxygen supply on tissue regeneration and repair [ [47] , [48] , [49] , [50] ]. However, the effect of local oxygen supply on tissue regeneration during the AF repair is still unclear.…”