Novel Epigenetic Modulation Chitosan-Based Scaffold as a Promising Bone Regenerative Material

Bone tissue engineering is a complicated field requiring concerted participation of cells, scaffolds, and osteoactive molecules to replace damaged bone. This study synthesized a chitosan-based (CS) scaffold incorporated with trichostatin A (TSA), an epigenetic modifier molecule, to achieve promising bone regeneration potential. The scaffolds with various biphasic calcium phosphate (BCP) proportions: 0%, 10%, 20%, and 40% were fabricated. The addition of BCP improved the scaffolds' mechanical properties and delayed the degradation rate, whereas 20% BCP scaffold matched the appropriate scaffold requirements. The proper concentration of TSA was also validated. Our developed scaffold released TSA and sustained them for up to three days. The scaffold with 800 nM of TSA showed excellent biocompatibility and induced robust osteoblast-related gene expression in the primary human periodontal ligament cells (hPDLCs). To evaluate in vivo bone regeneration potential, the scaffolds were implanted in the mice calvarial defect model. The excellent bone regeneration ability was further demonstrated in the micro-CT and histology sections compared to both negative control and commercial bone graft product. New bone formed in the CS/BCP/TSA group revealed a trabeculae-liked characteristic of the mature bone as early as six weeks. The CS/BCP/TSA scaffold is an up-and-coming candidate for the bone tissue engineering scaffold.