What Is NAD+?
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme present in every living cell. Its most fundamental role is as a redox carrier: it cycles between its oxidized form (NAD+) and reduced form (NADH), shuttling electrons through glycolysis, the citric acid cycle, and oxidative phosphorylation. Without this cycling, cells cannot efficiently convert nutrients into usable energy.
Because it is a coenzyme rather than a peptide, NAD+ is studied as a metabolic cofactor. This guide frames it accurately as such, distinct from the peptides elsewhere in this library.
NAD+ As A Signaling Substrate: Sirtuins And PARPs
Beyond energy metabolism, NAD+ is consumed as a substrate by several important enzyme families. Sirtuins use NAD+ to remove acetyl and other groups from proteins, which links the cell’s energy state to gene expression, stress resistance, and mitochondrial function. PARP enzymes use NAD+ during DNA-damage repair, and CD38 consumes it in immune-signaling contexts.
This makes NAD+ availability a shared currency: when it is abundant, sirtuin and repair pathways can operate; when it is depleted, they compete for a shrinking pool. That competition is a recurring theme in aging research.
- NAD+ is the central redox coenzyme for cellular energy production.
- It is the required substrate for sirtuins (protein deacylation) and PARPs (DNA repair).
- Cellular NAD+ levels decline with age in many tissues in research models.
- It is a coenzyme, not a peptide — studied as a metabolic cofactor.
Research Context And Handling
NAD+ features in aging, mitochondrial-function, and DNA-repair research, and is often studied alongside its biosynthetic precursors and the enzymes that consume it. Common in vitro readouts include NAD+/NADH ratio assays, sirtuin-activity assays, and mitochondrial-respiration measurements. As with any Research Use Only compound, verified identity and purity, appropriate storage, and interpretation against the primary literature are essential. It is supplied strictly for laboratory research and not for human or animal use.
Research Use Only: This guide is informational and describes research-context handling of compounds intended strictly for in vitro laboratory research. Products are not for human or animal consumption, ingestion, or injection, and are not FDA-approved. Nothing here is medical, clinical, or dosing advice.
Frequently Asked Questions
Is NAD+ a peptide?
No. NAD+ (nicotinamide adenine dinucleotide) is a coenzyme, not a peptide. It is included in the research library because it is central to cellular energy metabolism and longevity research.
Why is NAD+ important in longevity research?
NAD+ is the required substrate for sirtuins and PARP DNA-repair enzymes, linking a cell’s energy state to gene expression and repair. Cellular NAD+ declines with age in many tissues, a recurring theme in aging research.
What are sirtuins?
Sirtuins are enzymes that use NAD+ to remove acetyl and other groups from proteins, connecting metabolic state to stress resistance and mitochondrial function. Their activity depends on NAD+ availability.