Figure 3.

Gene expression in empty plasmids (pEGFP) and osteoprotegerin (OPG) recombinant (pOPG) cells. For gene expression analysis, ΔΔCt was used; gene fold changes were calculated as the difference in gene expression between control group (empty plasmid transfected cells) and experiment group (OPG recombinant transfected cells). Gene fold changes were considered significant when P < .05 (**P < .01). In the control group, the gene expression level was normalized to 1, and the experiment group results indicated relative fold changes to the control group. Data were the means of triplicates with standard deviation indicated. The data showed that Runx2 was significantly suppressed, and Smad1 and Akt1 were significantly upregulated in the experiment group, but the RANKL expression was not significantly changed (t-test; **P < .001).