Figure 8.

NS398 blocked the RANKL induction of SAA1 and SAA2 expression in hBMMs but did not affect osteoclast-like cell numbers, and SAA1 and SAA2 inhibited PTH-stimulated osteoblastic differentiation in hBMSCs. (a–c) hBMMs were treated with M-CSF (30 ng/mL) plus vehicle (VEH) or M-CSF plus RANKL (30 ng/mL each) with/without NS398 (100 nM). (a) SAA1 and SAA2 protein measurement in the culture medium of hBMMs measured by ELISA. (b) SAA1 and SAA2 mRNA at day 3. (c) TRAP-stained microscopic images at ×100 original magnification (scale bars, 200 µm) and TRAP⁺ MNC counts per well. (d) ALPL (alkaline phosphatase) and BGLAP (osteocalcin) mRNA expression in hBMSCs at day 21 treated with VEH or PTH in presence of OPG (100 ng/mL) to prevent osteoclastogenesis with/without rhSAA1 (10 µg/mL) or rhSAA2 (10 to 50 ng/mL). Data are means ± SEM for n = 3 independent samples. For (a), **P < 0.01, significantly different from VEH treated at same time point, determined by two-tailed unpaired t test. For (c), **P < 0.01, significantly different from day 4, determined by one-way ANOVA, post hoc Bonferroni pairwise multiple comparisons. For (b) and (d), *P < 0.05, **P < 0.01, determined by two-way ANOVA, post hoc Bonferroni pairwise multiple comparisons.