Bioglass-Reinforced Spongin-Like Collagen Scaffolds for Osteoporotic Bone Tissue Engineering

Osteoporotic fractures pose a significant clinical challenge due to impaired bone regeneration. In this study, composite scaffolds based on Bioglass 45S5 (BG) and marine-derived spongin-like collagen (SPG) were developed and analyzed. Characterization techniques included scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) to assess morphology and chemical composition of the components. In vitro analyses involved genotoxicity testing by micronucleus assay in CHOK-1 cells and assessment of mineralization potential using Alizarin Red S staining in MC3T3-E1 preosteoblasts. In vivo performance was evaluated through implantation in tibial bone defects of ovariectomized rats, followed by histological, histomorphometric, and immunohistochemical analyses at 15- and 30-days postsurgery. The characterization confirmed the successful obtation of the components, with SEM revealing distinct BG particles and fibrillar SPG architecture, and FTIR identifying the presence of key chemical bonds from both components. In vitro, BG/SPG scaffolds showed no genotoxic effects and significantly enhanced calcium deposition compared to BG alone, indicating superior mineralization capacity. In vivo, the composite scaffolds promoted greater bone regeneration than BG alone, with higher bone volume (BV/TV), increased osteoblast activity (N.Ob/T.Ar and Ob.S/BS), and greater collagen deposition. Immunostaining for RUNX-2 and OPG also confirmed elevated osteogenic activity in the BG/SPG group. These findings demonstrate that BG/SPG scaffolds possess excellent structural integrity, safety, and biological performance, supporting their potential use in bone tissue engineering applications for osteoporotic bone repair.