Abstract: Objective: To explore the feasibility of increasing the RANKL/OPG ratio by using the RNAi technique to silence rat OPG gene of bone marrow mesenchymal stem cells (BMSCs) in vitro. Methods: BMSCs were set up in the empty vector group and OPG silencing group. RT-PCR was used to detect the mRNA expression of OPG and RANKL. Western blot was used to detect the protein expression of OPG and RANKL. Results: The expressions of OPG mRNA and protein in OPG silencing group were significantly inhibited and the expression of RANKL mRNA was significantly increased (P<0.05) compared with the empty vector group. There was no significant difference in the expressions of RANKL protein between two groups (P>0.05). The expressions of RANKL/OPG mRNA and protein in OPG silencing group were significantly increased. The difference was statistically significant (P<0.05). Conclusion: It is feasible to increase the RANKL/OPG ratio by using the lentivirus as vector and silencing OPG gene of rat BMSCs by RNAi technique in vitro.

Key words: Bone mesenchymal stem cells , OPG , RNAi, RANKL , RANKL/OPG