HUVECs were treated with CSE (0.5% and 1.0%) and H2O2 (25, 50 and 100 μM) for indicated time points. A) CSE and H2O2 increased the phosphorylation of SIRT1 (at Ser27 and Ser47). B) and C) Histograms represent relative intensity of phosphorylated SIRT1 levels compared to respective control treatments (n=3). *P < 0.05, **P < 0.01, ***P < 0.001 vs. controls. p-SIRT1 (Ser27), phosphorylation of SIRT1 at Ser27; p- SIRT1 (Ser47), phosphorylation of SIRT1 at Ser 47.