Polyvinyl alcohol/pectin hydrogels incorporating marine elastin hydrolysates for enhanced wound healing and...

Hydrogels are extensively used in advanced wound care owing to their superior water-retention capacity and biocompatibility. However, their limited bioactivity often hampers effective tissue regeneration. Although marine-derived biomolecules exhibit considerable regenerative potential, they remain underexplored in hydrogel-based wound dressing systems. In this study, we aimed to develop a bioactive hydrogel dressing by incorporating marine-derived elastin hydrolysates into a physically cross-linked polyvinyl alcohol (PVA)/pectin matrix to promote extracellular matrix remodeling. Insoluble elastin was isolated from the bulbus arteriosus of tuna (Thunnus orientalis) (IET), characterized, and hydrolyzed using either Alcalase (Al-IET) or gastrointestinal enzymes (GI-IET). The hydrolysates exhibited excellent in vitro biocompatibility with human dermal fibroblasts (HDFs) and keratinocytes. In HDFs, Al-IET and GI-IET upregulated collagen type I and α-smooth muscle actin expression. Scratch assays demonstrated that Al-IET promoted fibroblast migration in a dose- and time-dependent manner, indicating its role in early wound healing. Al-IET was incorporated into PVA/Pectin hydrogels via freeze-thaw crosslinking. The resulting hydrogels exhibited favorable physicochemical properties, swelling behavior, drug release, and rheological stability, with no cytotoxicity. Furthermore, hydrogel eluates promoted HDF migration. In a murine dorsal wound model, the PVA/Pectin hydrogel with 0.025% Al-IET significantly accelerated wound closure and enhanced regeneration, with dense collagen deposition by day 14 postinjury. These findings highlight the potential of elastin hydrolysate-loaded PVA/Pectin hydrogel as a bioactive wound dressing with structural integrity.