Multifunctional Bioactive Nanozyme Systems for Enhanced Diabetic Wound Healing

The protracted transition from inflammation to proliferation in diabetic wound healing poses significant challenges, exacerbated by persistent inflammatory responses and inadequate vascularization. To address these issues, a novel nanozymatic therapeutic approach utilizing asymmetrically structured MnO₂-Au-mSiO₂@aFGF Janus nanoparticles is engineered. Nanozymes featuring a mSiO₂ head and MnO₂ extensions, into which acidic fibroblast growth factor (aFGF) is encapsulated, resulting in MnO₂-Au-mSiO₂@aFGF Janus nanoparticles (mSAM@aFGF), are synthesized. This nanozyme system effectively emulates enzymatic activities of catalase (CAT) and superoxide dismutase (SOD), catalyzing degradation of reactive oxygen species (ROS) and generating oxygen. In addition, controlled release of aFGF fosters tissue regeneration and vascularization. In vitro studies demonstrate that mSAM@aFGF significantly alleviates oxidative stress in cells, and enhances cell proliferation, migration, and angiogenesis. An injectable hydrogel based on photocrosslinked hyaluronic acid (HAMA), incorporating the nanozymatic ROS-scavenging and growth factor-releasing system, is developed. The HAMA-mSAM@aFGF hydrogel exhibits multifaceted benefits in a diabetic wound model, including injectability, wound adhesion, hemostasis, anti-inflammatory effects, macrophage polarization from M1 to M2 phenotype, and promotion of vascularization. These attributes underscore the potential of this system to facilitate transition from chronic inflammation to the proliferative phase of wound repair, offering a promising therapeutic strategy for diabetic wound management.