Phosphorous pentoxide-free bioactive glass exhibits dose-dependent angiogenic and osteogenic capacities which are retained in glass polymeric composite scaffolds

• Published in: Biomaterials science 2021-11, Vol.9 (23), p.7876-7894
• Main Authors: Font Tellado, Sonia, Delgado, José Angel, Poh, Su Ping Patrina, Zhang, Wen, García-Vallés, Maite, Martínez, Salvador, Gorustovich, Alejandro, Morejón, Lizette, van Griensven, Martijn, Balmayor, Elizabeth Rosado
• Format: Article
• Language: English
• Subjects: Alkaline phosphatase; Angiogenesis Inducing Agents; Animals; Biocompatibility; Biocompatible Materials; Bioglass; Biological activity; Biomarkers; Biomedical materials; Deposition; Embryos; Gene expression; Glass; Growth factors; Humans; Modulus of elasticity; Osteogenesis; Particulate composites; Phosphorus Compounds; Scaffolds; Silicon Dioxide; Stem cells; Tissue engineering; Vascular endothelial growth factor; Vascular Endothelial Growth Factor A; Zebrafish
• ISSN: 2047-4830; 2047-4849
• DOI: 10.1039/d1bm01311d

Bioactive glasses (BGs) are attractive materials for bone tissue engineering because of their bioactivity and osteoinductivity. In this study, we report the synthesis of a novel phosphorous pentoxide-free, silicate-based bioactive glass (52S-BG) composed of 52.1% SiO 2 , 23.2% Na 2 O and 22.6% CaO (wt%). The glass was thoroughly characterized. The biocompatibility and osteogenic properties of 52S-BG particles were analyzed in vitro with human adipose-derived mesenchymal stem cells (AdMSCs) and human osteoblasts. 52S-BG particles were biocompatible and induced mineralized matrix deposition and the expression of osteogenic markers (RunX2, alkaline phosphatase, osteocalcin, osteopontin, collagen I) and the angiogenic marker vascular endothelial growth factor (VEGF). Angiogenic properties were additionally confirmed in a zebrafish embryo model. 52S-BG was added to poly- -caprolactone (PCL) to obtain a composite with 10 wt% glass content. Composite PCL/52S-BG scaffolds were fabricated by additive manufacturing and displayed high porosity (76%) and pore interconnectivity. The incorporation of 52S-BG particles increased the Young's modulus of PCL scaffolds from 180 to 230 MPa. AdMSC seeding efficiency and proliferation were higher in PCL/52S-BG compared to PCL scaffolds, indicating improved biocompatibility. Finally, 52S-BG incorporation improved the scaffolds' osteogenic and angiogenic properties by increasing mineral deposition and inducing relevant gene expression and VEGF protein secretion. Overall, 52S-BG particles and PCL/52S-BG composites may be attractive for diverse bone engineering applications requiring concomitant angiogenic properties. New P 2 O 5 -free, silicate-based bioactive glass showing angiogenic and osteogenic properties. Glass polymeric composite scaffolds showed improved mechanics and biocompatibility while stimulating cell differentiation.