Figure 5.

SIRT1 overexpression and nicotinamide mononucleotide (NMN) supplementation suppress apoptosis induction by sorafenib. HUH7 cells were stimulated with sorafenib (5 µM), NMN (250 µM), or a combination of sorafenib and NMN. (A) SIRT1 was overexpressed in HUH7 cells by electroporation. Apoptosis was determined by FITC Annexin V Apoptosis Detection Kit and flow cytometry. Annexin V-FITC positive cells and Annexin-V-FITC and PI-positive cells were defined as apoptotic cells (n = 3). (B) Intracellular NAD levels were measured by gradient HPLC/UV analysis (n = 3). (C) Phosphorylated AMPK was normalized to total AMPK and loading control (Tubulin). One representative blot out of three experiments is shown. The mean value of solvent control (DMSO) was used to normalize values of the respective datasets. One representative blot out of three experiments is shown. Data are shown as mean ± SEM. * p < 0.05.