SIRT1 regulates C2C12 myoblast cell proliferation by activating Wnt signaling pathway

Sirtuin type 1 (SIRT1) is a potent NAD+ dependent deacetylase that deacetylates histone and nonhistone proteins to regulate gene expression and protein activity. Emerging evidences have indicated that SIRT1 plays a significant role in diverse cellular processes including cell growth, differentiation, development, and physiological function in muscle cells; however the signaling mechanisms involved remain to be established. In order to investigate its potential role in muscle biological processes, we administrated C2C12 cells which were isolated from skeletal muscle tissue of dystrophic mice with SIRT1 activator resveratrol (REV), inhibitor nicotinamide (NAM) and Wnt inhibitor FH535. By CCK-8, BrdU assay, real-time PCR and Western blot, we investigated whether the SIRT1 has a function in C2C12 cells by promoting β-catenin accumulation. Our results demonstrate that SIRT1 increases cell proliferation of C2C12 myoblast in a SIRT1-dependent manner. And SIRT1 significantly up-regulates the expression of cyclin D1, C-myc and Dvl2 in vitro as well as stimulates the accumulation of the Wnt/β-catenin. In conclusion, this study indicates that SIRT1 promotes the proliferation of C2C12 myoblast cells, at least partly via Wnt signaling pathway.