Evaluation of osteoinduction of bioactive glass, magnesium oxide and calcitonin on mesenchymal stem cells in bacterial cellulose/ Silk scaffold

Abstract

Introduction: Bacterial cellulose (BC) and silk fibroin (SF) are natural polymers that have high mechanical strength and biocompatibility. The purpose of this study was to investigate the osteogenesis induced by magnesium oxide (MgO), bioactive glass and calcitonin in mesenchymal stem cells (MSCs) in BC and SF composite scaffolds. Materials and methods: Green synthesized MgO and bioactive glass nanoparticles were incorporated in BC and SF scaffolds. Scanning electron microscope (SEM) used to analyze the structural characteristics of scaffolds and Fourier transform infrared spectroscopy (FTIR) confirm the loaded of particles in the scaffolds. Porosity, swelling rate and degradability of scaffolds were carry out. Survival and differentiation of MSCs derived from human adipose tissue into bone cells in scaffolds were performed by MTT and expression genes of alkaline phosphatase, osteocalcin and RUNX2. Results: Biocompatibility, swelling rate and porosity increased in the BC/FS scaffolds incorporated with MgO nanoparticles (P< 0.05). Mechanical strength increased in SF and SF/BC scaffolds incorporated with MgO nanoparticles (P< 0.05). On the 21days, alkaline phosphatase enzyme activity and mineralization of calcitonin-treated cells were higher in the BC/SF composite scaffolds than in other scaffolds (P< 0.05). Alkaline phosphatase, osteocalcin gene expression increased on day 21 of differentiation in calcitonin-treated cells in BC/SF composite scaffolds, while on day 7 of differentiation, RUNX2 gene expression increased in these scaffolds (P< 0.05). Conclusion: The green synthesized MgO nanoparticles improved the physicochemical properties of SF and BC/SF composite scaffolds. Calcitonin, bioactive glass nanoparticles and MgO incorporated in BC/SF composite scaffolds were effective in differentiating MSCs to bone cells. Keywords: bone tissue engineering, magnesium oxide, bioactive glass, silk fibroin, bacterial cellulose.