Oxygen-Tolerant Hydrogenase-Ag Nanoclusters-Peptide Hydrogel for Light-Driven H₂ Therapy in Diabetic Wound Healing

Diabetic wound healing is hindered by excessive reactive oxygen species (ROS), while conventional hydrogen (H₂) delivery methods lack localized efficacy. Escherichia coli [NiFe]-hydrogenase 2 (Hyd-2), though promising for H₂ production, suffers from oxygen sensitivity. Here, we engineer a peptide hydrogel (Fmoc-KYF-AgNCs) that shields Hyd-2 from oxygen inactivation, enabling sustained light-driven H₂ generation under aerobic conditions (retaining 80% activity after 12 hours). In vitro, the hydrogel scavenges ROS in LPS-stimulated macrophages, suppresses pro-inflammatory cytokines, and enhances cell survival. In diabetic mice, the hydrogel accelerates wound closure (87% by day 11), reduces oxidative stress, promotes angiogenesis, and reprograms macrophages toward an anti-inflammatory M2 phenotype. Transcriptomic profiling reveals downregulation of inflammatory pathways and upregulation of tissue repair genes. This oxygen-tolerant system bridges enzymatic catalysis with precision medicine, offering a translatable platform for diabetic wound therapy and expanding hydrogenase applications in oxidative stress-related disorders.