Photosensitive small intestinal submucosal hydrogels loaded with the KR-12-a5 peptide promote periodontal...

Periodontitis, a chronic inflammatory condition, causes progressive loss of oral soft and hard tissues. Current treatments struggle to balance antimicrobial efficacy with bone regeneration. This study aimed to develop a photoresponsive hydrogel using porcine small intestinal submucosa (SIS) crosslinked with itaconic anhydride (IA) and incorporating the KR-12-a5 peptide to enhance its antibacterial and osteogenic capabilities.

Crosslinking SIS with IA significantly improved the hydrogel's mechanical and biological properties. Adding KR-12-a5 enhanced biocompatibility, promoted cell proliferation and migration, and demonstrated strong antimicrobial activity against Staphylococcus aureus, Fusobacterium nucleatum, Porphyromonas gingivalis, and Streptococcus hemolyticus. The hydrogel boosted mineralization capacity and expression of osteogenic markers (ALP, BMP-2, OPN, RUNX-2) in bone marrow stromal cells in vitro. In vivo, the IA/SIS/KR-12-a5 hydrogel promoted autologous bone formation at defect margins and reduced inflammatory cell infiltration, outperforming SIS and IA/SIS groups in both osteogenic and anti-inflammatory effects.

The IA/SIS/KR-12-a5 hydrogel exhibited rapid UV-induced gelation, strong mechanical properties, antibacterial efficacy, and significant osteogenic potential. These attributes suggest its suitability as an injectable biomaterial for bone regeneration and repair.