Research Paper Volume 4, Issue 6 pp 436—447

Figure 2. AS101 increases SIRT1 protein activity in vitro and in vivo.

(A) AS101 induces activity of recombinant SIRT1. To determine in vitro SIRT1 activity, recombinant SIRT1 was incubated with AS101 at different concentration (0.1-2.5 μg/ml) or with PBS for 1 hour. Activity was examined based on SIRT1 de-acetylation of a fluorogenic acetylated peptide substrate. Results shown are average ±SEM of three independent experiments (#p=0.05,*p<0.05 versus PBS). (B-C) AS101 treatment reduces the acetylation levels of SIRT1 substrates. In vivo SIRT1 activity was measured by de-acetylation of its substrates PGC1α (B), and p53 (C) in rat liver extracts from treated for 14 days with AS101 or PBS at different concentrations. To detect acetylation levels, immunoprecipitated PGC1α and p53 were immunoblotted with antibodies against themselves and against pan acetyl antibodies. IgG was used as a control for the immunoprecipitation. Results shown are representative of the experiments from three independent replicates that gave similar results.