Innovative Hydrogel Formulation Combining Phycocyanin and Probiotic for Enhancing Skin Regeneration and Accelerated Wound Healing: A Preclinical Investigation in Wistar Rats.

Skin repair is a global concern that requires multifunctional wound healing platforms that accelerate healing and shield the wound from external contamination. Phycocyanin (C-PC) is a natural protein that shows favorable characteristics for skin repair. The present study aims to investigate the synergistic wound healing potential of probiotic Pediococcus pentosaceus and C-PC hydrogel formulation. C-PC whey protein nanofibrils (WPINF) were first prepared and evaluated for particle size, % entrapment efficiency, and zeta potential. Selected WPINF was used to prepare several hydrogel formulations which were further evaluated for physical properties and in vitro C-PC release. Formulation with acceptable physical properties and C-PC release was studied for oxidative stress markers, antioxidant biomarkers, and wound healing effect in animal models. WPINF had acceptable particle size (26.59-153.5 nm), % EE (65.76-95.98%), and zeta potential (22.3-26.1 mV). The developed hydrogels exhibited neutral pH values (6.97-7.10), optimal spreadability (5.60-7.50 cm), and viscosity (123-209 Pa). HEC-based hydrogel (F1) showed superior C-PC release which was found to follow Higuchi diffusion. In vivo, hydrogel formulations (with and without probiotic) showed significantly reduced oxidative stress markers, with MDA reduced by 54.76-98.58% and antioxidant biomarkers (GSH and TAC) ensuring successful delivery of therapeutic compounds. Histological analysis showed improved re-epithelialization, reduced inflammation, and well-formed granulation tissue in treated groups, with probiotic-C-PC group demonstrating additional immunomodulatory effects. The study highlights promising potential of C-PC-probiotic hydrogels as a safe and effective biotherapeutics for wound healing, supporting their advancement into further clinical investigations to validate their efficacy in humans.