Effects of parthenolide on osteoclast differentiation of RAW264. 7 cell induced by receptor activator of nuclear factor κB ligand

Abstract

Objective To study the effects of parthenolide on osteoclast differentiation of RAW264. 7 cell induced by receptor activator of nuclear factor κB ligand (RANKL). Methods The mouse macrophage RAW264.7 cells induced by RANKL was used alone as the control group, different concentrations of parthenolide (0.5, 1, 2 μmol/L) were added to culture the RAW264.7 cells. On the third, fifth and seventh day, the tartrate resistant acid phosphatase (TRAP) staining method was used to detect osteodast-like cells and the cell number was count; the contents of tartrate resistant acid phosphatase (TRAP5b) in the Culture supernatant of each groups were detected by enzyme linked immunosorbent assay (ELISA) and the expression of osteodast marker gene alcitonin receptor (CTR) and matrix metalloproteinase (MMP)-9 in each groups were detected by realtime-polymerase chain reaction (PCR) on the seventh day. We use Chisquare test and t test to test the differences between groups by SPSS 17.0. Results In different culture conditions, RANKL could always induce the RAW264.7 cell differentiate into mature osteoclasts. Compared with the control group at the same time control group, on the third, fifth and seventh day, he number of mature osteoclasts induced were obviously decreased in groups adding different concentration of PAR; the number of induced osteoclasts decreased along with the increase of parthenolide concentration, on the seventh day in 0.5, 1, 2 μmol/L concentration PAR groups, the number of mature osteoclasts compared with the control group were descended 36.3%, 40.8%, 49.3% (t=7.758, 8.742, 10.56; P<0.05); the contents of TRAP5b in the culture supernatant were consistent with the cell counting results on the seventh day(P<0.05). The expression of CTR and MMP-9 by TRAP positive osteoclasts decreased along with the increase of parthenolide concentration, and the 2 μmol/L group was the lowest. Compared with the control group, there were statistically significant differences with the different PAR concentration groups 0.5, 1, 2 μmol/L (P<0.05). Conclusion Parthenolide can inhibit RANKL induced RAW264.7 differentiation into osteoclast cells, and the inhibition is dose dependent. Key words: Osteoclasts; Parthenolide; Receptor activator of nuclear factor-Kappa B ligand; Tartrate resistant acid phosphatase