Figure 4.

Effects of S100B in skeletal muscle regeneration. A: S100B is passively released from acutely injured skeletal muscle tissue early after injury. Whether S100B activates quiescent muscle satellite cells (SCs) is not known (?); B: Released S100B may stimulate myoblast proliferation and simultaneously activate the myogenic program via receptor for advanced glycation end-products (RAGE) engagement, during the next few days post-injury (early regeneration phase); C: However, during the intermediate regeneration phase (i.e., from day 3 to day 7 post-injury, in coincidence with the peak of released bFGF and the myoblast proliferation phase), S100B may enhance bFGF-FGFR1 mitogenic signaling thereby contributing to expand the myoblast population while simultaneously inactivating its canonical receptor, RAGE. RAGE: Receptor for advanced glycation end-products.