Fig. 8.

Individual RAR antagonist and pan-RAR antagonist were unable to rescue the inhibitory effect of ATRA on osteoclastogenesis. a Representative microscopic image of osteoclast formed in presence of BMP2/7 and/or ATRA ± 1.5 μΜ ER or 1.5 μΜ LE, or 1.5 μΜ MM at day 7. Red arrow indicates the TRAP-positive multinucleated osteoclast. b Semi-quantitative analysis of osteoclast numbers from the groups mentioned in (a). X indicates nil. All data are presented as mean ± SD, from three independent experiments. Significant effect of the treatment, **p < 0.01 and ****p < 0.0001. Significant difference also existed compared to the indicated group: ^a ATRA, ^e ER + no ATRAP, ^ea ER + ATRA, ^l LE + no ATRA, ^la LE + ATRA, ^m MM + no ATRA, ^ma MM + ATRA. ER: RARα-antagonist ER50891, LE: RARβ-antagonist LE135, and MM: RARγ-antagonist MM11253