FIGURE 7.

A–C, activation of AMPK by CA-α1AMPK expression increases NAD⁺ content and NAD⁺/NADH ratio in macrophages. RAW264.7 macrophages were transfected with CA-α1AMPK expression vectors. NAD⁺ and NADH nucleotides were measured with a NAD⁺/NADH quantification kit. D and E, activation of AMPK increases SIRT1 mRNA expression in macrophages. RAW264.7 macrophages were treated with 2 mm AICAR (D) or transfected with CA-α1AMPK overnight (E). F, AICAR increases SIRT1 protein expression in macrophages. Peritoneal macrophages were treated with AICAR (2 mm) at the indicated time points. SIRT1 mRNA was measured by real time RT-PCR. SIRT1 protein expression was measured by immunoblotting. All data are expressed as mean ± S.E., n = 4; *, p < 0.05.