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This page was last updated on 2026-04-11 and is reviewed periodically as new material appears.
Nicotinamide mononucleotide, abbreviated NMN, is a naturally occurring nucleotide found in cells. Its structure consists of a nicotinamide ring linked to ribose phosphate, and the compound serves as an intermediate in the salvage pathway for nicotinamide adenine dinucleotide, or NAD+. In this pathway, nicotinamide phosphoribosyltransferase converts nicotinamide and phosphoribosyl pyrophosphate into NMN, after which NMN adenylyltransferase attaches an adenylate group to produce NAD+. Because NAD+ participates in redox reactions and signaling, NMN occupies a central position in cellular metabolism. The molecule is distinct from nicotinamide riboside, though the two are related in NAD+ precursor research.
Beyond its intracellular synthesis, NMN can be taken up from the extracellular environment, although the routes are still debated. Some evidence points to direct transport into cells through specific transporters, while other work suggests dephosphorylation to nicotinamide riboside followed by cellular uptake. Once inside, NMN can be converted to NAD+ by NMN adenylyltransferases; the relative contribution of these routes may differ by tissue, species, and experimental conditions. Researchers continue to investigate which mechanisms dominate in intact organisms and how they affect measured NAD+ levels. Direct measurement in tissues remains technically challenging because NMN can be rapidly metabolized during sample collection.
NMN occurs in many living systems, including bacteria, yeast, plants, and mammals. Dietary sources are present in foods such as edamame, avocado, broccoli, and various meats, but amounts vary widely and are generally lower than those used in research settings. Laboratory production often relies on enzymatic synthesis or chemical phosphorylation of nicotinamide riboside, and commercial material is typically supplied as a white to off-white powder. Because NMN is hygroscopic and sensitive to heat, moisture, and pH extremes, its handling requires care to preserve identity and purity. Aqueous preparation should be done with attention to pH and temperature to limit hydrolysis.
Nicotinamide mononucleotide is usually handled as a dry powder because moisture can promote hydrolysis and shorten shelf life. Recommended storage conditions often include a desiccated container at minus twenty degrees Celsius or colder, with protection from light. Aqueous solutions are less stable than solid material and may degrade faster at ambient temperature or neutral pH. Repeated freeze-thaw cycles can introduce variability, so aliquoting is common in laboratory settings. These practices reflect general nucleotide chemistry rather than a single universal protocol.
Analytical laboratories identify and quantify NMN using several complementary techniques. High-performance liquid chromatography with ultraviolet detection is widely used for purity and assay work. Liquid chromatography coupled to mass spectrometry provides greater sensitivity and is common for biological matrices. Nuclear magnetic resonance spectroscopy supports structural confirmation and can distinguish related nucleotides. Accurate measurement depends on reference standards, validated methods, and careful sample preparation, especially because NMN can convert to related compounds under some conditions.
| Property | Value | Notes |
|---|---|---|
| Chemical formula | C11H15N2O8P | Neutral form; often supplied as a salt or hydrate. |
| Molecular weight | 334.22 g/mol | Calculated for C11H15N2O8P. |
| Appearance | White to off-white powder | Color can vary with purity and hydration. |
| Solubility | Soluble in water | Aqueous solutions are acidic and stability depends on pH and temperature. |
| Typical storage | −20 °C or below, desiccated | Protect from light; avoid repeated freeze-thaw cycles. |
Nicotinamide mononucleotide, commonly abbreviated NMN, is a naturally occurring nucleotide. Its structure combines a nicotinamide ring with a ribose sugar and a phosphate group. The compound appears in cells across many organisms as an intermediate in the production of nicotinamide adenine dinucleotide, or NAD+. Because NMN sits close to NAD+ in metabolism, it has drawn interest in biochemistry and aging research. The molecule is not a dietary essential nutrient in the classical sense, and its presence in food is generally low and variable.
NAD+ serves as a coenzyme in redox reactions and as a substrate for enzymes involved in DNA repair and cellular signaling. In the salvage pathway, nicotinamide is converted to NMN by the enzyme NAMPT. NMN is then converted to NAD+ by NMNAT enzymes. A separate route links nicotinamide riboside to NMN through phosphorylation. These pathways maintain NAD+ levels, which can decline with age or metabolic stress in some tissues. The relative contribution of circulating NMN to tissue NAD+ remains an active area of study.
Analytical measurement of NMN typically uses reversed-phase high-performance liquid chromatography with ultraviolet detection near 260 nm. Mass spectrometry, often coupled to liquid chromatography, provides sensitive quantification and confirmatory identification in biological matrices. Nuclear magnetic resonance spectroscopy is used to verify molecular structure and distinguish related nucleotides. Because NMN is polar and poorly retained on conventional reversed-phase columns, ion-pairing reagents or hydrophilic interaction chromatography are sometimes employed. Reported purity values depend on the chosen method, calibration standard, and whether related substances are resolved.
Stability studies indicate that NMN is sensitive to heat, light, and pH extremes. In aqueous solution, hydrolysis can cleave the phosphate linkage or convert NMN to related nicotinamide derivatives, with degradation accelerating at elevated temperatures and alkaline conditions. Solid material is generally more stable when kept dry and cold, and research-grade supplies are often stored at minus twenty degrees Celsius or lower, protected from light and moisture. Repeated freeze-thaw cycles of solutions can promote degradation, so aliquoting is a common laboratory practice. The exact shelf life depends on purity, counterion, packaging, and storage history.
Two enzymatic steps define the canonical route from nicotinamide to NAD+. Nicotinamide phosphoribosyltransferase, known as NAMPT, produces NMN from nicotinamide and phosphoribosyl pyrophosphate. NMN adenylyltransferases, or NMNAT enzymes, then couple NMN with ATP to form NAD+. Whether intact NMN crosses cell membranes efficiently remains an active area of investigation; some studies propose direct transport, while others emphasize extracellular dephosphorylation to nicotinamide riboside followed by uptake. The relative contribution of each route likely depends on cell type, tissue, and experimental conditions.
Trace amounts of NMN have been reported in certain plant foods, including edamame, avocado, broccoli, cucumber, and cabbage. Reported concentrations vary widely because analytical methods differ and food matrices complicate extraction. Endogenous production in cells is generally considered more quantitatively important than dietary intake, though precise human turnover rates are difficult to establish. Commercial NMN for research or consumer products is commonly made through enzymatic synthesis or chemical phosphorylation routes. Regulatory classification differs by country; in some jurisdictions NMN is sold as a supplement, while in others it is treated as a novel food ingredient or restricted substance.
== Clinical use == Alpha-glucosidase inhibitors are used to establish greater glycemic control over hyperglycemia in diabetes mellitus type 2, particularly with regard to postprandial hyperglycemia. The intake of a single dose before a meal containing complex carbohydrates clearly suppresses the glucose spike and may decrease the postprandial hyperglycemia (higher than 140 mg/dL; >7.8 mmol/L) in patients with type II diabetes. This ability is observed in the native/raw state of the alpha-amylase inhibitor; therefore, its consumption inside a meal that undergo heating (baking, frying or cooking/boiling) is expected to blunt its property to decrease the activity of carbohydrate digesting enzymes. They may be used as monotherapy in conjunction with an appropriate diabetic diet and exercise, or they may be used in conjunction with other anti-diabetic drugs. A Cochrane systematic review assessed the effect of AGIs in people with impaired glucose tolerance, impaired fasting blood glucose, elevated glycated hemoglobin A1c (HbA1c). It was found that Acarbose appeared to reduce incidence of diabetes mellitus type 2 when compared to placebo, however there was no conclusive evidence that acarbose compare to diet and exercise, metformin, placebo, no intervention improved all-cause mortality, reduced or increased risk of cardiovascular mortality, serious or non-serious adverse events, non-fatal stroke, congestive heart failure, or non-fatal myocardial infarction.
Carbamic acid, which might also be called aminoformic acid or aminocarboxylic acid, is the chemical compound with the formula H2NCOOH. It can be obtained by the reaction of ammonia NH3 and carbon dioxide CO2 at very low temperatures, which also yields ammonium carbamate [NH4]+[NH2CO2]−. The compound is stable only up to about 250 K (−23 °C); at higher temperatures it decomposes into those two gases. The solid apparently consists of dimers, with the two molecules connected by hydrogen bonds between the two carboxyl groups –COOH. Carbamic acid could be seen as both an amine and carboxylic acid, and therefore an amino acid; however, the attachment of the carboxyl group –COOH directly to the nitrogen atom (without any intermediate carbon chain) makes it behave very differently from the amino acids with intermediate carbon chain. (Glycine NH2CH2COOH is generally considered to be the simplest amino acid.) The hydroxyl group –OH attached to the carbon also excludes it from the amide class. The term "carbamic acid" is also used generically for any compounds of the form RR′NCOOH, where R and R′ are organic groups or hydrogen. Deprotonation of a carbamic acid yields a carbamate anion RR′NCOO−, the salts of which can be relatively stable. Carbamate is also a term used for esters of carbamic acids, such as methyl carbamate H2N−C(=O)−OCH3. The carbamoyl functional group RR′N–C(=O)– (often denoted by Cbm) is the carbamic acid molecule minus the OH part of the carboxyl.
== Finite elasticity == The elastic behavior of objects that undergo finite deformations has been described using a number of models, such as Cauchy elastic material models, Hypoelastic material models, and Hyperelastic material models. The deformation gradient (F) is the primary deformation measure used in finite strain theory.
Sources: en.wikipedia.org
== Pharmacological modulation == Neutral endopeptidase (NEP) also known as neprilysin is the enzyme that metabolizes natriuretic peptides. Several inhibitors of NEP are currently being developed to treat disorders ranging from hypertension to heart failure. Most of them are dual inhibitors (NEP and ACE). In 2014, PARADIGM-HF study was published in NEJM. This study considered as a landmark study in treatment of heart failure. The study was double blinded; compared LCZ696 versus enalapril in patients with heart failure. The study showed lower all cause mortality, cardiovascular mortality and hospitalization in LCZ696 arm. Omapatrilat (dual inhibitor of NEP and angiotensin-converting enzyme) developed by BMS did not receive FDA approval due to angioedema safety concerns. Other dual inhibitors of NEP with ACE/angiotensin receptor are (in 2003) being developed by pharmaceutical companies.
== Epidemiology == An estimated 20 per million live births are diagnosed with EB, and 9 per million people in the general population have the condition. Of these cases, approximately 92% are EBS, 5% are DEB, 1% are JEB, and 2% are unclassified. Carrier frequency ranges from 1 in 333 for JEB, to 1 in 450 for DEB; the carrier frequency for EBS is presumed to be much higher than JEB or DEB. The disorder occurs in every racial and ethnic group and affects both sexes.
The PFA-100 (Platelet Function Assay or Platelet Function Analyser) is a platelet function analyser that aspirates blood in vitro from a blood specimen into disposable test cartridges through a microscopic aperture cut into a biologically active membrane at the end of a capillary. The membrane of the cartridges are coated with collagen and adenosine diphosphate (ADP) or collagen and epinephrine inducing a platelet plug to form which closes the aperture. The PFA test result is dependent on platelet function, plasma von Willebrand Factor level, platelet number, and (to some extent) the hematocrit (that is, the percent composition of red blood cells in the sample). The PFA test is initially performed with the Collagen/Epinepherine membrane. A normal Col/Epi closure time (<180 seconds) excludes the presence of a significant platelet function defect. If the Col/Epi closure time is prolonged (>180 seconds), the Col/ADP test is automatically performed. If the Col/ADP result is normal (<120 seconds), aspirin-induced platelet dysfunction is most likely. Prolongation of both test results (Col/Epi >180 seconds, Col/ADP >120 seconds) may indicate the following;
Sources: en.wikipedia.org
Sitagliptin/simvastatin, sold under the brand name Juvisync, is a fixed-dose combination anti-diabetic medication used to treat type 2 diabetes and hypercholesterolemia. It contains sitagliptin and simvastatin. Sitagliptin is a dipeptidyl peptidase-4 inhibitor and simvastatin is an HMG-CoA reductase inhibitor. These two disorders commonly occur in people at the same time, and have been typically treated with administration of these medications separately. The combination was approved in 2011, and sold under the brand name Juvisync by Merck. Juvisync was later removed from the market in 2013, due to business reasons.
=== Abuse of LGBTQ+ people === According to Amnesty International on 9 February 2024, two Houthi-run courts in Yemen sentenced 48 individuals either to death, flogging, or prison over charges related to same-sex conduct in the past month.
=== Redox-responsive nanogels === Redox-responsive nanogels generally contain crosslinks formed by disulfide bonds or specific crosslinking agents. Nanogels made of bioreducible and bifunctional monomers can also be used. In the presence of reducing agents such as glutathione, thioredoxin and peroxiredoxin, these nanogels respond by releasing their cargo. Given that these reducing agents and several others are found in larger concentrations inside cells compared to their external environment, redox-responsive nanogels are a promising strategy for targeted intracellular delivery.
Sources: en.wikipedia.org
NMN is nicotinamide mononucleotide, a nucleotide intermediate in NAD+ biosynthesis. It consists of nicotinamide, ribose, and phosphate groups.
No. NMN is a precursor, while NAD+ is the dinucleotide product formed after an adenylate group is added. They are distinct molecules with different cellular roles.
Small amounts of NMN have been reported in several foods, including some vegetables and meats. The concentrations are variable and usually much lower than those used in laboratory research.
Solid NMN is often kept cool, dry, and protected from light. Long-term storage may use temperatures at or below minus twenty degrees Celsius. Moisture and repeated temperature changes should be avoided.