Carboxymethyl chitin or chitosan for osteoinduction effect on the human periodontal ligament stem cells

Human periodontal ligament stem cells (hPDLSCs) are seeding cells for tissue-engineered treatment of alveolar bone regeneration. To elucidate carboxymethyl chitosan (CMCTS) and carboxymethyl chitin (CMCT) effect on osteogenic differentiation, hPDLSCs were isolated and treated with CMCTS or CMCT. Cell viability and multiplication capacity were measured. The expression of classic osteogenic related molecules, including Alkaline Phosphatase (ALP), Phosphoprotein 1 (OPN), RUNX family transcription factor 2 (Runx2) and Osteocalcin (OCN), were determined. Mineralization levels were detected by Alizarin Red staining. Results showed that both CMCTS and CMCT treatment had the maximal promoting ability for hPDLSCs viability below the concentration of 100 μg/mL, while CMCTS improved hPDLSCs mineralization significantly. CMCTS induced multiple-factor high expression, including ALP, Runx2, OPN and OCN, whereas slightly osteoinductive bioactivity of CMCT was mainly due to ALP. Therefore, CMCTS had a more significant advantage for osteoinductive differentiation of hPDLSCs than CMCT, which may be a promising material for periodontal regeneration.