Mg-integrated octopus-inspired hydrogel dressing enables autonomous adhesion and wound closure for enhanced healing...

Diabetic wounds are characterized by persistent infection, excessive oxidative stress, and impaired healing. Conventional dressings often lack autonomous adhesion and wound-closure capabilities, and fail to balance essential antimicrobial and anti-inflammatory properties. Inspired by the sucker morphology and thermo-responsive behavior of the octopus, this study developed a Three-Dimensional (3D)-printed, photosensitive/thermosensitive dual-responsive poly(N-isopropylacrylamide) (PNIPAM)/gelatin hydrogel dressing. The hydrogel was functionalized with mesoporous MgO nanoparticles coated with self-assembled curcumin and polydopamine (MCP NPs). Under near-infrared (NIR) irradiation, the hydrogel achieved robust tissue adhesion (∼2.3 N cm^-2) facilitated by biomimetic sucker structures and integrated adhesive groups. The MCP NPs, stabilized by π-π stacking and electrostatic interactions, enabled sequential reactive oxygen species generation and scavenging. During the repair process, NIR-triggered controllable contraction allowed the hydrogel to actively close wounds, exert potent antibacterial effects, and promote extracellular matrix remodeling through the activation of the Hippo and Fibroblast Growth Factor (FGF) signaling pathways. By integrating antioxidant activity, bioactive Mg²⁺ ions release, and photothermal therapy, the hydrogel effectively inhibited macrophage pyroptosis and restored the mitochondrial membrane potential. Furthermore, it reprogrammed macrophages from the metabolic and immune perspectives by modulating the glycolysis/gluconeogenesis and Interleukin-10 (IL-10) pathways, while suppressing the NF-κB pathway. In diabetic rat models, the hydrogel significantly accelerated angiogenesis and re-epithelialization, achieving wound closure four days earlier than the untreated group. Overall, this study presents a promising strategy for the effective clinical management of infected diabetic wounds.