Alloy nanozyme-reinforced hyaluronic acid-based hydrogel with wound environment-responsive properties for synergistically accelerating infectious wound healing.

The recovery of infectious wound tissues presents a significant global health challenge due to the impediments posed by the harsh healing microenvironment, which includes ongoing bacterial invasion, high oxidative stress, inflammatory response, and impaired angiogenesis. To overcome the above issues, we propose a composite hydrogel based on the multiple-crosslinked mechanism involving the covalent network of CC bonds within catechol and maleic-modified HA (CMHA), the self-assembly network of glycyrrhizic acid (GA), and the metal-polyphenol coordination induced by ZHMCe for accelerating infectious wound healing. The resulting CMHA/GA/ZHMCe hydrogels demonstrate enhanced mechanical, adhesive, antioxidative, and antibacterial properties. Importantly, the hydrogel system possesses wound environment-responsive properties that allow it to adapt to the specific therapeutic requirements of different stages by regulating various enzyme activities in the healing of infected wounds. Furthermore, the biocompatible CMHA/GA/ZHMCe shows the ability to promote cell migration and angiogenesis in vitro while reprogramming macrophages toward an anti-inflammatory phenotype due to the effective release of active ingredients. In vivo experiments confirm that the CMHA/GA/ZHMCe hydrogel significantly enhances infectious wound healing by accelerating re-epithelialization, promoting collagen deposition, regulating inflammation, and contributing to vascularization. These findings underscore the therapeutic potential of our hydrogel dressings for the treatment of bacterially infected cutaneous wound healing.

Encapsulation of green tea polyphenol nanospheres in PVA/alginate hydrogel for promoting wound healing of diabetic rats by regulating PI3K/AKT pathway.

Difficult healing of skin wounds is one of the serious complications of diabetes mellitus. Green tea polyphenols (TP) have been found to have good therapeutic effects on wounds healing. However, TP that is soluble in water and easily been oxidized requires a gel material that provides moisture retention, oxidation prevention, and sustained release of TP to achieve better wound healing effect. Therefore, in this work, novel tea polyphenol nanospheres (TPN) were synthesized and encapsulated in a PVA /alginate hydrogel (TPN@H). The prepared TPN@H was characterized and applicated in model diabetic rats for promoting wound healing and regulating immune response. Fourier-transform infrared spectroscopy (FT-IR), UV spectroscopy, scanning electron microscopy (SEM), atomic force microscope (AFM), confocal laser scanning microscopy (CLSM), dynamic light scattering (DLS) and differential scanning calorimetry (DSC) were used for characterization. Animal experiments and molecular mechanism research proved that TPN@H could promote wound healing of diabetic rats by regulating PI3K/AKT signaling pathway.