NAD+: Why a Coenzyme Sits in a Peptide Catalog
Not a peptide but a coenzyme, and the reason it appears in longevity research is that sirtuins and PARPs cannot function without it.
NAD+ is not a peptide, and that is worth saying at the top of an article in a peptide catalog. It is a coenzyme — a small molecule present in every living cell — and it appears alongside peptides in longevity research because so many of the enzymes that research is interested in cannot function without it.
Everything below describes published preclinical and in-vitro research. It is not a therapeutic claim, not medical advice, and not a statement about effects in humans.
What it is
Nicotinamide adenine dinucleotide, molecular weight about 663 Da, built from a nicotinamide nucleotide and an adenine nucleotide joined by a phosphate bridge. It cycles between an oxidised form (NAD+) and a reduced form (NADH), and that cycling is the central electron-carrying reaction of metabolism.
Two roles run in parallel. As a redox cofactor it is consumed and regenerated continuously — the same molecules turning over. As a substrate for a family of enzymes including the sirtuins and PARPs, it is consumed and destroyed, which is what makes cellular supply a subject of study rather than a constant.
Why it appears in longevity research
- Sirtuins — a family of deacetylases that require NAD+ as a co-substrate. Their activity is therefore tied to NAD+ availability, which is the mechanistic link most of this literature is built on.
- PARP enzymes — involved in DNA repair and among the largest consumers of cellular NAD+, which sets up a documented competition between repair activity and sirtuin activity.
- Reported age-related decline — multiple studies describe falling tissue NAD+ levels with age across several species, and this observation is what turned a metabolism textbook entry into a research target.
- Mitochondrial function — work examining the relationship between NAD+ availability and oxidative phosphorylation capacity.
Practical notes
| Class | Coenzyme, not a peptide |
|---|---|
| Molecular weight | ~663 Da |
| Forms | NAD+ (oxidised), NADH (reduced) |
| Key enzyme families | Sirtuins, PARPs |
| Typical vial size | 100 mg |
Because it is not a peptide, some of the usual handling logic does not transfer directly. NAD+ is more prone to hydrolysis in solution than most of the peptides in this catalog and is notably pH sensitive — it degrades faster in alkaline conditions. Prepare fresh where a protocol allows it rather than relying on a long-lived stock.
Reading this literature critically
- NAD+ is not an approved medicine in the European Union or anywhere else.
- Much of the published enthusiasm concerns precursors — nicotinamide riboside and nicotinamide mononucleotide — rather than NAD+ itself, and results from precursor studies are frequently reported as though they were NAD+ studies. Check which molecule was used.
- The age-related decline observation is well replicated; what it causes is not settled, and correlation with age is not a mechanism.
- Cellular uptake of intact NAD+ is itself contested in the literature, which is exactly why the precursor research exists.
Handling
Supplied as lyophilised powder at 100 mg — the largest vial in the range, so recalculate rather than assuming the usual concentrations. Our reconstitution calculator handles the arithmetic and the storage notes cover degradation.
Every batch is analysed by an independent laboratory for purity and identity, with batch-matched certificates available on request. See the NAD+ 100mg product page, or the rest of longevity research.
All products and information referenced are for in-vitro research and laboratory use only. Nothing here is medical advice, and no therapeutic claim is made or implied.