A Sustained-Release SP-Sr-CaS/NBD Microsphere for Promoting Bone Repair and Inhibiting Inflammation for the Treatment of Osteomyelitis

Abstract

In this study, we prepare sustained-release poly(lactide-co-glycolide) (PLGA)-based microspheres (SP), containing strontium (Sr), calcium sulfate (CaS), and NF-κB essential modifier-binding domain (NBD) peptide, namely SP-Sr-CaS/NBD, for the treatment of osteomyelitis. Our results demonstrate that the SP-Sr-CaS/NBD group exhibited enhanced bone repair speed and infection clearance rate compared to other groups. Moreover, histological staining revealed more comprehensive bone structure restoration in the SP-Sr-CaS/NBD group. Furthermore, we assessed the levels of bone growth factors and apoptosis factors in primary bone marrow mesenchymal stem cells and found that NBD effectively suppresses inflammation while Sr-CaS promotes bone healing by inhibiting cell apoptosis. Additionally, we conducted in vitro and in vivo toxicity evaluations of the microspheres, which confirmed their potential as a competitive filling material for osteomyelitis. In conclusion, SP-Sr-CaS/NBD microspheres hold great promise as therapeutic scaffolds for clinical cases involving bone infections by reducing pain and treatment duration. This study provides a new repair material for the treatment of osteomyelitis and promotes the development of repair material for osteomyelitis.