Figure 7.

SIRT1 silencing activates FoxO3a and drives Bnip3 expression. Cortical neuron cultures were treated with lentiviral particles expressing shRNA to reduce the transcription of SIRT1. A, B, Real-time PCR indicated a dramatic reduction of SIRT1 mRNA levels (A) and immunoreactivity (B) 72 h after infection. C, At 72 h after infection, acetylated FoxO3a levels were enhanced in the SIRT1 shRNA group relative to the scrambled control. D, E, FoxO3a binding to the Bnip3 promoter region (determined by ChIP) was enhanced more than threefold (D) and Bnip3 mRNA levels were increased more than twofold (E) by 72 h of SIRT1 shRNA treament. *p < 0.05, **p < 0.01, and ***p < 0.001, compared with control shRNA group using unpaired t tests. All data are reported as the mean ± SEM (n = 5–7).