The aging process is strongly linked to epigenetic drift—a gradual breakdown in the structural packing of DNA that causes cells to lose their identity and express incorrect genes. Sirtuins are a family of NAD+-dependent deacetylase enzymes responsible for maintaining chromatin structure and genomic stability.
### The Mechanism of STACs
Sirtuin Activating Compounds (STACs) act as direct or indirect allosteric modulators that increase sirtuin enzyme activity toward target substrates:
* **Resveratrol:** A stilbenoid polyphenol that binds to SIRT1, boosting its affinity for acetylated protein substrates.
* **Pterostilbene:** A natural methylated derivative of resveratrol with vastly superior oral bioavailability and plasma lipophilicity.
### Key Rejuvenation Pathways
1. **Histone Deacetylation:** Keeps heterochromatin tightly wound, silencing aberrant gene transcription.
2. **Mitochondrial Protection:** SIRT3 activation inside mitochondria detoxifies reactive oxygen species and stabilizes energy output.
3. **Inflammation Suppression:** Suppresses NF-kB signaling, curbing systemic inflammatory responses.
### Optimization Strategy
Pairing STACs with NAD+ boosters provides both the enzyme activator (STAC) and the required biological fuel (NAD+) for maximum cellular sirtuin activity.