SIRT7 is a NAD-dependent histone deacetylase that plays crucial roles in cellular homeostasis and aging regulation 1. The protein is predominantly localized in the nucleus and nucleolus, where it specifically mediates deacetylation of histone H3 at lysine-18 (H3K18Ac), acting as a transcriptional repressor 1. SIRT7 stimulates ribosomal RNA transcription by deacetylating RNA polymerase I subunits and regulates pre-rRNA processing 1. Beyond histone modifications, SIRT7 deacetylates numerous non-histone proteins including ATM, CDK9, and various transcription factors, thereby regulating DNA repair, transcription, and metabolic processes 1. The protein serves as a critical regulator of aging and cellular senescence, with its decline associated with metabolic dysfunction and age-related pathologies 2. During senescence, SIRT7 undergoes proteasomal degradation via the E3 ligase TRIP12, leading to increased chr17 binding of NUCKS1 and activation of inflammatory gene expression 3. SIRT7 dysfunction is implicated in cardiovascular diseases, with reduced levels observed in pulmonary hypertension patients 4. Additionally, SIRT7 can be upregulated by ketone bodies, potentially contributing to cardiac fibrosis through inhibition of mitochondrial biogenesis 5.