Inhibition of BMP and p38 MAPK Pathways

Dorsomorphin (DM (6-[4-(2-piperidin-1-yl-ethoxy)phenyl]-3-pyridin-4-yl-pyrazolo[1,5-a]pyrimidine) (Sigma-Aldrich S.r.l., Milano, Italy), a selective inhibitor of BMP type I receptors [22 (link),23 (link),24 (link)] and SB203580 (Cell Signaling Technology Inc., Euroclone, Milano, Italy), a pyridinyl imidazole inhibitor widely used to inhibit p38 MAPK [25 (link)], were added to culture medium in the three treatment groups (OM + PEMFs; OM + BMP2; OM + PEMFs + BMP2) for the whole culture period. SB203580 was used at 10 µM as commonly recommended for cell culture experiments [25 (link),42 (link)], DM was used at different concentrations (0, 5, 10, 20 μM) [24 (link)] in preliminary experiments to evaluate p-SMAD1/5/8 activation by Western blotting. Cell viability was assessed using Prestoblue assay (Invitrogen by Life Technologies, Monza, Italy) [41 (link)].