Self-sacrificial bioenzyme-reinforced injectable hydrogel bone adhesives for enhancing diabetic fracture healing

The increased risk of diabetic fractures, driven by high oxidative stress and a proinflammatory response at the site of bone injury, remains a treatment challenge. Traditional internal fixation materials pose numerous limitations, prompting the emergence of new biomaterials as superior alternatives due to advancements in bone tissue engineering research. This study develops an injectable magnesium-gallate (MgGA) bioenzyme-reinforced hydrogel bone adhesive to remodel the local inflammatory microenvironment and enhance diabetic fracture healing. The MgGA bioenzyme significantly improves toughness and bone adhesive strength owing to its interaction with polymer chains. The MgGA-containing, catalyst-like injectable bone adhesive facilitates the scavenging of overexpressed reactive oxygen species, promotes macrophage polarization to the M2 phenotype, and attenuates early-stage inflammation. The pathological tissue microenvironment-responsive MgGA enables the self-sacrificial and sustained release of Mg 2+ and gallic acid, regulating redox balance and promoting angiogenesis and osteogenesis. The developed MgGA hydrogel serves as a promising multifunctional bone adhesive, offering fracture fixation and accelerating diabetic bone regeneration in vivo, thereby representing a novel strategy for treating diabetic fractures.