What is NAD+?
NAD+ (nicotinamide adenine dinucleotide, oxidized form) is a dinucleotide coenzyme: an adenosine and a nicotinamide riboside joined through a diphosphate bridge (PubChem CID 5892). It contains no amino acids and is not a peptide.
Redox enzymes use it to carry electrons from one reaction to another, cycling between NAD+ and its reduced form, NADH, while sirtuins, poly(ADP-ribose) polymerases (PARPs) and CD38 consume it as a cosubstrate (Verdin, 2015; Covarrubias et al., 2021). Disguised Alpha supplies NAD+ as buffered lyophilized powder and as a 200 mg/mL liquid for laboratory research use only. Nothing on this page is guidance for use in people.
NAD+ reference data
| Property | Value |
|---|---|
| Name | NAD+ (Nicotinamide Adenine Dinucleotide) |
| Aliases | Nadide, beta-NAD, coenzyme I, diphosphopyridine nucleotide (PubChem CID 5892) |
| Compound class | Pyridine nucleotide coenzyme (a dinucleotide, not a peptide) |
| Molecular formula | C₂₁H₂₇N₇O₁₄P₂ |
| Molecular weight | 663.43 g/mol |
| Reduced form | NADH: C₂₁H₂₉N₇O₁₄P₂, 665.4 g/mol (PubChem CID 439153) |
| Phosphorylated form | NADP+: C₂₁H₂₈N₇O₁₇P₃, 743.4 g/mol (PubChem CID 5885) |
| Formats and sizes | Buffered lyophilized powder in 500MG (10ML) and 1000MG (10ML) vials; liquid, 200MG/ML in 20ML (4000MG total) |
| Container | Glass bottle |
| Testing | Third-party tested by ILS Laboratories and Chromate, with the certificate for each lot published on the product page and in the COA portal |
Formula, molecular weight, compound class, formats, sizes, container and storage are from the NAD+ product page. PubChem CID 5892 gives the same formula at 663.4 g/mol; the NADH and NADP+ rows are from PubChem. The vials are described as buffered, with the buffer unnamed, so use the NAD+ content measured on your lot's certificate for molar calculations.
See it beside the other compounds on this site in the peptide molecular weight reference table.
What the research covers
This guide covers six areas of the NAD+ literature. Each summary below states the model used.
Redox coenzyme: NAD+/NADH and NADP+/NADPH
NAD+ and NADH shuttle electrons into mitochondrial respiration and oxidative phosphorylation (Massudi et al., 2012). NADP+ carries an extra phosphate on the adenosine ribose (PubChem CID 5885) and is made only by NAD kinases, one of which was located in the mitochondria of human HEK293A cells (Ohashi et al., 2012). Cells keep the NADP pool mostly reduced, as NADPH, as a store of reducing equivalents against oxidative damage (Pollak et al., 2007), and hold both couples in separate, compartmentalized pools (Xiao et al., 2018). Models: biochemical reviews and human cell culture.
Sirtuins and PARPs
Yeast and mouse Sir2 proteins were shown to be NAD-dependent histone deacetylases, and in yeast that activity accounted for gene silencing, suppression of rDNA recombination and longer replicative lifespan (Imai et al., 2000). In mouse fibroblasts, nicotinamide phosphoribosyltransferase (NAMPT) was rate-limiting for NAD synthesis from nicotinamide, and raising it increased cellular NAD and Sir2α activity (Revollo et al., 2004). PARPs draw on the same pool: deleting PARP-1, a major NAD+ consumer, raised NAD+ and SIRT1 activity in mouse brown fat and muscle (Bai et al., 2011).
CD38 and NAD+ breakdown
Tissues from CD38-deficient mice held 10 to 20 times more NAD than wild-type tissues, with NADase activity essentially absent from most of them, and CD38 makes about one cyclic ADP-ribose for every 100 NAD molecules it hydrolyzes (Aksoy et al., 2006). In aging mice, CD38 expression and activity rose, and CD38 was required for the age-related NAD decline and mitochondrial dysfunction, partly through SIRT3; it was also the main enzyme degrading the precursor nicotinamide mononucleotide (NMN) in vivo (Camacho-Pereira et al., 2016).
Synthesis and uptake by cells
In human cells, nicotinamide, nicotinic acid and their nucleosides entered cells readily, while extracellular NAD and NMN were first degraded outside the cell into permeable precursors that were then rebuilt into cytosolic and mitochondrial NAD (Nikiforov et al., 2011).
NAD+ and age: what the data show
In pelvic skin from 49 people aged newborn to 77, NAD+ fell with age in both sexes while PARP activity rose with age in males (Massudi et al., 2012). A magnetic resonance method in healthy volunteers found lower NAD+ and higher NADH in older brains (Zhu et al., 2015), and plasma from people aged 20 to 87 showed lower NAD+ and NADP+ but higher NADH and NADPH with age (Clement et al., 2019).
In aged mice, tissue NAD+ was about 30 percent lower while synthesis flux was maintained, pointing to faster consumption (McReynolds et al., 2021). A review spanning yeast, worms, rodents, monkeys and humans found the evidence for an overall decline limited and often confined to one tissue, especially in humans (Peluso et al., 2021).
Measurement and stability in solution
During extraction, oxidized and reduced forms interconvert enough to distort NAD+/NADH and NADP+/NADPH ratios; in cultured mammalian cells and mouse tissues, an acidic acetonitrile:methanol:water extraction gave the least interconversion, followed by prompt neutralization (Lu et al., 2018). Over 43 days at 19 and 25°C, NAD+ and NADH were most stable in Tris buffer, with faster NADH loss in sodium phosphate or HEPES (Wolfe et al., 2024). NADPH degraded faster than NADH, at rates driven by temperature, acidity and phosphate or acetate concentration (Wu et al., 1986).
Recent research since 2024
This section covers studies indexed in PubMed since January 2024; each summary states the model used.
Linked NAD+ pools and mitochondrial buffering
To force chronic, compartment-specific NAD+ consumption, researchers engineered human cell lines that stably express PARP activity in the mitochondria, cytosol, endoplasmic reticulum or peroxisomes, lowering cellular NAD+ by up to 50%. Isotope-tracer flux measurements and mathematical modeling showed that the lower NAD+ concentration kinetically restricted consumption to balance a biosynthesis rate that did not change. Mitochondria imported NAD+ through SLC25A51 and, when NMNAT3 was present, held a reserve by reversibly cleaving it to nicotinamide mononucleotide and ATP. The cells tolerated chronic NAD+ deficiency unless mitochondria were targeted directly (Høyland et al., 2024). Model: engineered human cell lines.
Uric acid as an endogenous CD38 inhibitor
In enzyme assays and metabolic assays in cells and mice, soluble uric acid directly inhibited both the hydrolase and cyclase activities of CD38 through a reversible, non-competitive mechanism, limiting NAD+ degradation. Within purine metabolism the effect was specific to uric acid, and comparisons with methyl analogs such as caffeine metabolites pointed to 1,3-dihydroimidazol-2-one as the main functional group.
In mice, plasma uric acid at the human physiological minimum lowered serum IL-1β and IL-18 after a 2 mg/kg crude lipopolysaccharide challenge but not after 20 mg/kg, and limited monosodium urate crystal-induced peritonitis through CD38 (Wen et al., 2024). Models: recombinant CD38, cultured cells, and wild-type and CD38 knockout mice.
Whole-blood NAD+ across seven human cohorts
Using an ultra-high-performance liquid chromatography and high-resolution mass spectrometry system validated to account for real-world analytical variability, researchers quantified NAD+ in whole blood from seven independent human cohorts. Whole-blood NAD+ stayed stable with age and across lifestyle interventions, but shifted in response to the NAD+ precursor nicotinamide riboside, as the authors expected. They concluded that these findings challenge the use of blood NAD+ levels as a biomarker of aging or lifestyle factors (Trętowicz et al., 2026). Model: human whole blood from seven cohorts.
Key studies
- Imai S, et al. "Transcriptional silencing and longevity protein Sir2 is an NAD-dependent histone deacetylase." Nature. 2000. PMID 10693811. DOI 10.1038/35001622. Yeast genetics and purified yeast and mouse Sir2.
- Aksoy P, et al. "Regulation of intracellular levels of NAD: a novel role for CD38." Biochem Biophys Res Commun. 2006. PMID 16730329. DOI 10.1016/j.bbrc.2006.05.042. Wild-type and CD38-deficient mouse tissues.
- Nikiforov A, et al. "Pathways and subcellular compartmentation of NAD biosynthesis in human cells: from entry of extracellular precursors to mitochondrial NAD generation." J Biol Chem. 2011. PMID 21504897. DOI 10.1074/jbc.M110.213298. Human cell lines.
- Massudi H, et al. "Age-associated changes in oxidative stress and NAD+ metabolism in human tissue." PLoS One. 2012. PMID 22848760. DOI 10.1371/journal.pone.0042357. Human skin samples, newborn to 77 years.
- Camacho-Pereira J, et al. "CD38 Dictates Age-Related NAD Decline and Mitochondrial Dysfunction through an SIRT3-Dependent Mechanism." Cell Metab. 2016. PMID 27304511. DOI 10.1016/j.cmet.2016.05.006. Aging and CD38-knockout mice.
- Lu W, et al. "Extraction and Quantitation of Nicotinamide Adenine Dinucleotide Redox Cofactors." Antioxid Redox Signal. 2018. PMID 28497978. DOI 10.1089/ars.2017.7014. Cultured cells and mouse tissues, LC-MS.
- McReynolds MR, et al. "NAD(+) flux is maintained in aged mice despite lower tissue concentrations." Cell Syst. 2021. PMID 34559996. DOI 10.1016/j.cels.2021.09.001. Aged mice, isotope tracing.
- Wen S, et al. "Functional identification of soluble uric acid as an endogenous inhibitor of CD38." Elife. 2024. PMID 39527634. DOI 10.7554/eLife.96962. Recombinant CD38, cultured cells, wild-type and CD38 knockout mice.
- Høyland LE, et al. "Subcellular NAD(+) pools are interconnected and buffered by mitochondrial NAD(+)." Nat Metab. 2024. PMID 39702414. DOI 10.1038/s42255-024-01174-w. Engineered human cell lines, isotope tracing.
- Trętowicz MM, et al. "Human whole-blood NAD(+) levels do not vary with age or lifestyle interventions." Nat Metab. 2026. PMID 42135539. DOI 10.1038/s42255-026-01537-5. Human whole blood from seven cohorts, LC-MS.
Handling and storage of NAD+
General laboratory practice for this material:
- Follow the storage instructions on the product page for the size you have, keep material protected from light, and avoid freeze/thaw cycles once a solution is made.
- The storage panel describes the lyophilized powder and gives no separate condition for the 200 mg/mL liquid, so follow that bottle's label. The product ships in glass; inspect it on arrival.
- The vial buffer is not named, so check the pH of reconstituted solutions before use.
- Buffer and temperature affect stability: NAD+ and NADH lasted longest in Tris of three buffers tested (Wolfe et al., 2024), and reduced forms degrade faster in acid and in phosphate (Wu et al., 1986). Prepare working solutions fresh and keep them cold.
- In culture, extracellular NAD is broken down before cells take it up (Nikiforov et al., 2011), so measure intracellular NAD+ rather than assume intact uptake.
- Record the lot number and keep its certificate with your notes.
Frequently asked questions
What is NAD+?
NAD+ is the oxidized form of nicotinamide adenine dinucleotide, a coenzyme found in all living cells that carries electrons in redox reactions and is consumed as a cosubstrate by sirtuins and PARPs (Verdin, 2015).
Is NAD+ a peptide?
No. A peptide is a chain of amino acids joined by peptide bonds. NAD+ is a dinucleotide, two nucleotides joined through phosphate groups, with no amino acids, and its formula, C₂₁H₂₇N₇O₁₄P₂, contains phosphorus (PubChem CID 5892). It is stocked alongside research peptides, but chemically it is a nucleotide coenzyme.
Is NAD+ a coenzyme, and is NADH an enzyme?
NAD+ is a coenzyme: redox enzymes use it to carry electrons, and sirtuins, PARPs and CD38 use it as a consumed cosubstrate (Verdin, 2015; Covarrubias et al., 2021). NADH is not an enzyme. It is the reduced form of the same coenzyme, the form that carries the electrons, so it is a coenzyme as well.
NAD+ vs NADH vs NADP+: what is the difference?
NAD+ is the oxidized coenzyme (663.4 g/mol) and NADH the reduced form that carries electrons (665.4 g/mol). NADP+ (743.4 g/mol) is NAD+ with an extra phosphate on the adenosine ribose, made only by NAD kinases (Ohashi et al., 2012). The NAD pool mainly serves energy metabolism, while the NADP pool is kept mostly reduced as NADPH for antioxidant and detoxifying reactions (Pollak et al., 2007; Ying, 2008).
How should NAD+ be stored?
Follow the storage instructions on the product page for the size you have, keep material protected from light, and avoid freeze/thaw cycles once a solution is made. For the 200 mg/mL liquid, also follow the bottle label.
Where can researchers buy NAD+?
Disguised Alpha sells NAD+ for laboratory research as 500MG and 1000MG buffered lyophilized vials and a 200MG/ML liquid (20ML), third-party tested with each lot's certificate published on the product page: NAD+ (Nicotinamide Adenine Dinucleotide).
Related compounds and guides
- NAD+ Aerosol Spray: another NAD+ format
- MitoPrime (NAD+ / MOTs-C / 5-Amino-1MQ) and its research guide
- NMN (Nicotinamide Mononucleotide): an NAD+ precursor
- MOTS-c research guide and SS-31 research guide: mitochondrial research peptides
- Humanin (Mitochondrial Bioregulator) and its research guide
- COA portal: every published certificate, by lot
This product is for research use only. It has not been evaluated for safety or effectiveness in humans. Not for human consumption. All products are intended for laboratory research purposes only.