[Guling tablets promotes the proliferation and mineralization and regulates OPG/RANKL/M-CSF expression of osteoblasts...

To investigate the effect of Gulingpian (GLP, or Guling tablets) on the proliferation and mineralization of MG-63 cells and the involvement of p38 MAPK pathway in such processes.

MG-63 cells were cultured in the presence of p38 inhibitor SB203580 and or serum from rats fed with normal saline or GLP. The expression of the OPG, RANKL and M-CSF mRNA, cell proliferation and formation of mineralized bone nodule, the total protein of p38 and phosphorylated p38, were observed or quantitatively measured.

Treatment with GLP serum increased the level of p38 phosphorylation but did not affect the total p38 expression. GLP serum significantly promoted MG-63 cell proliferation and differentiation, resulting also in up-regulated OPG and down-regulated RANKL mRNA expressions without obvious alteration in M-CSF expression. These effects were blocked by the specific p38 inhibitor SB203580.

GLP promotes the proliferation and differentiation of osteoblasts and regulates OPG/RANKL expressions in vitro, which are mediated probably via the p38 MAPK pathway.