**3. Results and Discussion**

Previous studies have demonstrated high glucose inhibits proliferation and differentiation of osteoblasts [25]. Curcumin promotes osteogenic differentiation of osteoblasts [26]. The concentration of curcumin at 15 μmol/L showed a stronger osteogenic effect than that at 10 μmol/L, whereas it was not statistically significant, and the concentration of curcumin at 25 μmol/L showed obvious cytotoxicity [27,28]. Therefore, we grouped within the concentration range of 10μmol/l in our study. In addition, curcumin can induce cancerous cell apoptosis in specific doses and times through different pathways. However, it does not have a significant effect on normal cells in the same doses/times, which suggests that sensitivity of cells to curcumin varies under different conditions [28]. Therefore, the protective effect of curcumin on high glucose-induced apoptosis and the optimal concentration of curcumin in promoting osteogenesis in diabetic osteoporosis under different glucose concentrations are

still unclear. Our findings proved that curcumin effectively alleviates high glucose-induced negative effects on osteoblasts, its optimal concentration, and osteogenic impact on osteogenesis of osteoblasts under a series of glucose concentrations.
