Figure 7
Schematic representation of the inhibitory effects of IGF-1, suberanilohydroxamic acid (SAHA) and halofuginone (HAL) on the TGF-β pathway in keratocytes.
As shown with imaging flow cytometry, IGF-1, SAHA and halofuginone block Smad3 translocation to the nucleus. Inhibitory Smad7 forms as a negative-feedback loop53, blocking Smad3 phosphorylation and nuclearization. SAHA can also inhibit HDACs, which leads to acetylation and subsequent ubiquitination of Smad754, resulting in higher intracellular Smad7 levels, as observed in the present study. P, phosphate group; UB, ubiquitin; HDAC, histone deacetylase.
