Abstract: Objective To investigate the effect of hydroxyapatite (HA) on the osteogenic differentiation potency of adipose-derived mesenchymal stem cells (ADSCs). Methods ADSCs were isolated and purified from C57BL/6 mice. Toxic effects of hydroxyapatite on ADSCs were detected by cell proliferation assay. Alkaline phosphatase (ALP) assay was used to detect the effects of different concentrations of HA on osteogenic differentiation of ADSCs. Relative mRNA expression levels of osteogenic genes (BGLAP, ALP, COL1A1, OPN and Runx2) were measured by RT-PCR. Results The low concentration of HA (≤20 mg/L) showed less effect on proliferation of ADSCs. With the increase of HA concentration, the cell proliferation decreased. The co-culture of 20 mg/L HA with ADSCs significantly increased the ALP activity, and promoted the expression of osteoblast-related genes (P＜0.01). Conclusion Hydroxyapatite have the ability to induce the osteogenic differentiation of ADSCs, which provide a theoretical basis for combinating HA and ADSCs into a new bone engineering scaffold.

Key words: hydroxyapatites, mesenchymal stem cells, alkaline phosphatase, reverse transcriptase polymerase chain reaction, adipose-derived mesenchymal stem cells, osteogenic differentiation