Functionalized BLGFs/ODEX hydrogel scaffold incorporating Oreochromis lidole skin collagen for bone tissue regeneration

Background: Bones provide support to the body and protect vital internal organs. Bones have the capacity to repair minor defects, but this ability is substantially impaired in large defects. Mineralization, which is an essential stage of osteogenesis during bone defect repair, occurs through the deposition of calcium phosphate crystals to form the structural framework of bone tissue. In the present study, BLGFs/ODEX/COL hydrogel scaffolds were synthesized and characterized to determine their osteogenic differentiation capabilities. The hydrogel scaffolds were also applied to bone defect in SD rats and the regeneration of bone tissue was assessed. Methods: Whey protein was used to synthesize BLGMs which were later converted into BLGFs. Dextran underwent oxidation to yield ODEX while collagen was extracted from Chambo tilapia fish skin. The BLGFs solution and ODEX solution were mixed at a ratio of 3:1 to form BLGFs/ODEX hydrogel. To make BLGFs/ODEX/COL hydrogel, collagen was added to BLGFs/ODEX solution before its gelation. The mechanical characterization of the synthesized hydrogel scaffolds was done by FTIR and SEM. In vitro assessments of the hydrogels were evaluated to determine cell viability, hemocompatibility and osteogenic differentiation capability. The hydrogels were also applied in a tibial bone defect to evaluate their potential in aiding bone tissue regeneration. Results: Characterization of the synthesized hydrogel scaffold demonstrated a more favorable porous microstructure compared to the BLGFs/ODEX hydrogel. In addition, the BLGFs/ODEX/COL hydrogel scaffolds showed enhanced cell viability, improved rBMSCs adhesion and proliferation, better hemocompatibility, and greater osteogenic differentiation potential relative to the BLGFs/ODEX hydrogel scaffolds. BLGFs/ODEX/COL hydrogel scaffolds also showed better performance in accelerating early bone defect closure and promoting advanced bone maturation than the BLGFs/ODEX hydrogel scaffolds. Conclusions: Incorporating Oreochromis lidole (Chambo tilapia) skin collagen into BLGFs/ODEX hydrogels significantly improves scaffold porosity, cytocompatibility, and osteoinductive capacity, leading to accelerated early bone defect closure and enhanced bone maturation in a rat tibial defect model. The BLGFs/ODEX/COL hydrogel scaffold is a promising candidate for bone tissue engineering applications.