Sirtuin 1 and Sirtuin 2 (SIRT1/2)

Sirtuin 1 and Sirtuin 2 (SIRT1 and SIRT2) are NAD+-dependent class III histone deacetylases that play key roles in epigenetic regulation and diverse biological processes, including chromatin remodeling, DNA repair, cell cycle control, metabolic regulation, and response to cellular stress[1][2][7][8]. SIRT1 is primarily localized in the nucleus (but can shuttle to the cytoplasm) and regulates transcription, apoptosis, inflammation, and metabolism through deacetylation of histone and non-histone proteins (e.g., p53, FOXO, NF-κB)[2][8]. SIRT2 is mainly cytoplasmic—also shuttling to the nucleus during mitosis—where it deacetylates α-tubulin and other substrates, regulating microtubule dynamics, the cell cycle, differentiation, inflammation, and aging[3][8][9]. Both have been implicated as therapeutic targets in cancer, neurodegenerative, cardiovascular, and metabolic diseases, but their context-dependent roles pose both promise and challenges for drug development[4][7][8].

Other names

Sirtuin 1 (SIRT1)Sirt1NAD-dependent deacetylase sirtuin-1Sirtuin 2 (SIRT2)Sirt2NAD-dependent deacetylase sirtuin-2Hst2 (yeast homolog)

Inhibitors: Block deacetylase (and mono-ADP ribosyltransferase, in the case of SIRT2) activity, modulating acetylation of histones and non-histone proteins, affecting gene expression, cell survival, and disease pathways[2][7][9]. Activators: Enhance deacetylase activity, promoting stress resistance, metabolism, and longevity pathways[2][7].