The MEK1/2 signaling pathway was activated in the SIRT2-expressing cells. EpSCs were pretreated with a TrkB antagonist (ANA-12) or MEK1/2 inhibitor (PD0325901) for 2 h and then cocultured with M2 from the WT mice. The levels of p-TrkB, p-MEK1/2, p-ERK1/2, SIRT2 and β-actin were detected by western blot analysis.