Resveratrol is not a direct activator of SIRT1 enzyme activity.
Level 5 - mechanism / opinion, no new human data
In vitro and cell-based laboratory bench research without human participants.
PubMed 19843076 · doi:10.1111/j.1747-0285.2009.00901.x
What was done
The authors investigated whether resveratrol directly activates SIRT1 deacetylase activity using biochemical and cell-based assays. They evaluated the requirement of the covalently linked fluorophore on the standard Fluor de Lys-SIRT1 peptide substrate and assessed SIRT1 deacetylation in the presence of resveratrol using native substrates, including a p53-derived peptide and acetylated PGC-1alpha.
What was found
The abstract provides qualitative findings without numerical metrics. The Fluor de Lys-SIRT1 peptide was shown to be an artificial substrate that SIRT1 does not deacetylate without the covalently linked fluorophore. Resveratrol failed to activate SIRT1 in vitro against a p53-derived peptide or acetylated PGC-1alpha isolated from cells. Furthermore, although SIRT1 deacetylated PGC-1alpha in vitro and in cell-based assays, resveratrol did not stimulate SIRT1 activity under these conditions.
Why it matters
This study shows that reported direct catalytic activation of SIRT1 by resveratrol was an artifact of synthetic fluorescent screening substrates, challenging the premise that resveratrol directly stimulates SIRT1 enzymatic activity in vivo.
Limits
The study is restricted to cell-free and cell-culture models with no in vivo animal or human data. The abstract reports no quantitative values such as kinetic rates, concentrations tested, or statistical replicates, and it does not rule out indirect mechanisms of SIRT1 modulation by resveratrol.
Cited by
- supports Resveratrol and pterostilbene do not increase the activity of the SIRT1 enzyme.