Figure 4.

Co-culturing MC3T3 cells with the myostatin-modified osteocyte-derived exosomes inactivated Wnt signaling. As shown in Fig. 1A, Ocy454 cells were differentiated for 12 days and were treated with 100 ng/ml myostatin or vehicle for 48 h followed by the isolation of exosomes released form Ocy454 cells. MC3T3 cells were then co-cultured with the myostatin-modified osteocytic exosomes for 48 h. A, changes in mRNA levels of Wnt signaling-related genes Tcf7, SOST, RANKL, and DKK2 in MC3T3 cells were determined by real-time PCR. B, Western blotting was performed on total proteins from MC3T3 cells. Images shown in (Ba) were representative Western blotting. Bb, blots in (Ba) were quantified by scanning densitometry and normalized relative to β-tubulin. Data are expressed as the mean ± S.E. for three separate determinations. *, p < 0.05; ***, p < 0.001 versus the indicated group.