Figure 7.

Starvation enhances the effect of SIRT inhibitors and knock down of sirtuins reduces cell viability. (A) JVM-3 and (B) MEC-2 cells were exposed to EX-527 or sirtinol in normal and nutrient deprived medium for 24 hr. Apoptosis was measured by Annexin V/PtdIns staining followed by flow cytometry. Statistically significant differences (by Student t test) between un-starved and starved cells is indicated by an asterisk (*, P< 0.01, **, P < 0.001; ***, P < 0.0001). (C, D) JVM-3 and MEC-2 were transiently transduced with lentivirus containing short hairpin RNA for SIRT1 or SIRT2. Cell viability was measured using MTT assay following 48 hr. of transduction. The error bars represent SDs of mean and statistically significant differences (by Student t test) between cells tranduced with scrambeled and/or SIRT-shRNA are indicated by an asterisk (*, P < 0.01, **, P < 0.001; ***, P < 0.0001).