Figure 1. Effect of 17β-E2 on the expression level of SIRT1 in hFOB1.19 osteoblasts. (A) Western blotting showed the expression level of SIRT1 in osteoblasts treated with 17β-E2 (0, 10-8, 10-7, 10-6 M) for 24 h. Histogram showed the relative expression of SIRT1 normalized to β-actin protein, and the densitometry analysis of the blots were estimated by using Image J Software. (B) The expression of SIRT1 mRNA in osteoblasts treated with 17β-E2 (0, 10-8, 10-7, 10-6 M) for 24 h, and was assessed using RT-PCR. The data were normalized to GAPDH. Results were expressed as the means ± SD from 3 independent experiments. Statistically significance was evaluated using the Student’s t-test. * P < 0.05 vs. the control group was considered significant.