FIG. 7.

Cartoon depicting schematically the proposed underlying molecular mechanism(s) governing the healing of calvarial defects treated with SB431542. Inhibition of TGFβ signaling by SB431542 treatment leads to activation of BMP signaling through stimulation of the pro-osteogenic BMP2 ligand production in DM cells migrating into the area of defect. These cells from an immature status promptly differentiate along the osteogenic lineage, thus participating in the healing of bone. Furthermore, SB431542 upregulates inhibitory Smad6 in response to elevated BMP2, thus providing a negative feedback loop to contain excessive BMP signaling. Color images available online at www.liebertpub.com/tea