Effects of recombinant human connective tissue growth factor on the expression of osteoprotegerin and receptor activator of NF-κB ligand in human osteoblasts / 中华内分泌代谢杂志

ABSTRACT

Objective To investigate the effects of recombinant human connective tissue growth factor (rCTGF) on the expression of osteoprotegerin (OPG) and RANKL ( receptor activator of NF-κB ligand ) in human osteoblasts, as well as the mechanisms involved. Methods Human osteoblasts were treated with rCTGF. The expressions of OPG and RANKL were assessed by Western blotting. The expressions of focal adhesion kinase ( FAK), mitogen-activated protein kinase (MAPK) were also observed. Results rCTGF inhibited RANKL protein expression in a dose-and time-depentent manner in human osteoblasts, while the expression of OPG kept unchanged. rCTGF induced activation of p38MAPK and dephosphorylation of FAK in human osteoblasts, but had no effect on ERK and JNK phosphorylation. p38MAPK inhibitor SB23058 abrogated the inhibitory effect of rCTGF on RANKL in human osteoblasts. Conclusion rCTGF inhibits the expression of RANKL in human osteoblasts via activation of p38MAPK and dephosphorylation of FAK.