Photopolymerizable fish collagen peptide-GelMa composite hydrogels for dental pulp regeneration.

Marine-derived biomaterials, such as fish collagen peptides (FCP), have attracted significant attention for their applications in tissue regeneration due to their excellent biological properties. This study aims to develop and characterize a FCP-GelMa composite hydrogel and evaluate its potential for dental pulp regeneration in vitro and in vivo. A 0.2 mg/mL concentration of FCP was chosen for hydrogel fabrication. The resulting FCP-GelMa hydrogel exhibited a porous structure, a swelling ratio of 348%, and complete degradation within 24 h following collagenase exposure. In vitro, FCP-GelMa significantly enhanced dental pulp stem cells (DPSCs) proliferation, migration, and multi-lineage differentiation, and upregulated key genes such as runt-related transcription factor 2 (Runx 2), platelet endothelial cell adhesion molecule-1 (CD31), dentin matrix protein 1 (DMP-1), nestin, and glutathione peroxidase 4 (GPX4). Western blot analysis confirmed elevated levels of Runx2 and CD31 proteins. After 12 weeks of transplantation in nude mice, vascularized pulp-like tissue formation was observed, as evidenced by histological analysis showing positive immunostaining for CD31 and DSPP. In conclusion, FCP-GelMa demonstrates favorable biocompatibility and shows its promising potential for pulp-like tissue regeneration.