RNA interference-mediated osteoprotegerin silencing increases the receptor activator of nuclear factor-kappa B ligand/osteoprotegerin ratio and promotes osteoclastogenesis

Figure 3 The mRNA levels of receptor activator of nuclear factor-kappa B ligand and osteoprotegerin genes in each group. A and B: On the 3^rd, 7^th, 14^th, and 21^st day post-transfection, real-time quantitative polymerase chain reaction was used to evaluate the mRNA levels of osteoprotegerin (OPG) (A) and receptor activator of nuclear factor-kappa B ligand (RANKL) (B) in each group. The experimental group, “shOPG”, represents OPG gene-silenced bone marrow-derived mesenchymal stem cells (BMSCs) transfected with shOPG, while the control groups, “shScr” and “control”, represent BMSCs transfected with a scramble vector and untreated BMSCs, respectively. Compared to the shScr and control groups, RANKL was upregulated in shOPG-transfected BMSCs, particularly on day 3. Conversely, OPG expression was downregulated in shOPG-transfected BMSCs compared to the shScr and control groups (mean ± SEM, n = 3 experiments). ^aP < 0.05; ^bP < 0.01. BMSC: Bone marrow-derived mesenchymal stem cell; OPG: Osteoprotegerin; RANKL: Receptor activator of nuclear factor-kappa B ligand.