🧬NAD+ (Nicotinamide Adenine Dinucleotide)
The central electron carrier of cellular metabolism and obligate substrate for sirtuins (SIRT1–7), PARPs, and CD38. Declines 50% between ages 40–60.
Dinucleotide coenzymeWhat Is NAD+?
Nicotinamide Adenine Dinucleotide (NAD+) is a coenzyme found in all living cells. It is the obligate electron carrier in oxidative phosphorylation and the essential substrate for three longevity-regulating enzyme families: sirtuins (SIRT1–7), PARPs, and CD38. NAD+ levels decline ~50% between ages 40–60 — a decline now considered a primary molecular driver of biological aging.
Key Mechanisms
- Sirtuin activation (SIRT1–7) — deacetylases that regulate mitochondrial biogenesis, DNA repair, and metabolic homeostasis
- PARP-mediated DNA repair — repairs up to 70,000 single-strand DNA breaks per cell per day
- Complex I electron transport — NADH donates electrons to the mitochondrial ETC — rate-limiting for ATP production
- Circadian clock regulation — SIRT1 deacetylates core clock proteins BMAL1 and PER2
- AMPK cross-talk — via SIRT1→LKB1→AMPK axis, drives catabolic/repair longevity states
Research Applications
- Mitochondrial rejuvenation and age-related muscle decline
- DNA damage and repair kinetics in aging models
- Metabolic health and insulin sensitivity
- Neurodegeneration (Alzheimer's, Parkinson's preclinical models)
- Circadian biology research
Key References
- Gomes AP et al. "Declining NAD+ induces a pseudohypoxic state during aging." Cell, 2013;155(7):1624–1638.
- Verdin E. "NAD+ in aging, metabolism, and neurodegeneration." Science, 2015;350(6265):1208–1213.
- Yoshino M et al. "NMN increases muscle insulin sensitivity in prediabetic women." Science, 2021;372:1224–1229.
Frequently Asked Questions
NAD+ is the final coenzyme; NMN (nicotinamide mononucleotide) and NR (nicotinamide riboside) are precursors the body converts into NAD+ via the salvage pathway. Direct NAD+ administration versus precursor supplementation are studied as distinct research strategies with different pharmacokinetics.
NAD+ is the obligate substrate for sirtuins and PARPs — enzymes central to DNA repair and mitochondrial regulation — so its ~50% decline between ages 40–60 is considered one of the more actionable hallmarks of aging currently under research.
As a lyophilized or solution-stabilised compound depending on formulation. NAD+ is chemically less stable in solution than many peptides, so cold-chain handling and prompt use after reconstitution are especially important.