FIGURE 1.

A schematic diagram illustrating the known relationship between Sirt1 and IGF-1 signaling discussed in text. IGF-1 signaling may modulate Sirt1 activity in rat hepatoma cells (Cohen et al., 2004) as well as Sirt1 expression (Vinciguerra et al., 2009) in cardiomyocytes. On the other hand, Sirt1 have been shown to modulate IGF-1 signaling axis by deacetylation of IRS-2 in human embryonic kidney cells and rat cortical neurons (Li et al., 2008), as well as suppressing IGF-1 and IGF-1R expression in NG108-15 (a mouse neuroblastoma/rat glioma hybrid cell line; Sansone et al., 2013).