NAD⁺

Scientific identity. NAD⁺ is a dinucleotide comprising nicotinamide mononucleotide (NMN) linked through a pyrophosphate bond to adenosine monophosphate (AMP). The nicotinamide ring carries a quaternary nitrogen with a permanent positive charge — reflected in the "⁺" designation. In its reduced form (NADH), the nicotinamide ring accepts a hydride ion, carrying a hydrogen and two electrons as the primary electron carrier in cellular metabolism. The NAD⁺/NADH ratio is a fundamental measure of cellular redox state. NAD⁺ is also the substrate consumed — rather than reduced — by sirtuins, PARPs, and CD38/CD157, which cleave the glycosidic bond releasing nicotinamide and generating ADP-ribose or related products.

Compound class. Naturally occurring dinucleotide coenzyme; pyridine nucleotide; hydride-transfer coenzyme; NAD⁺-dependent enzyme substrate; cellular energy metabolism central mediator.

Primary research targets. Sirtuin deacylases (SIRT1–7); poly(ADP-ribose) polymerases (PARP1, PARP2); cyclic ADP-ribose synthases (CD38, CD157); NAD⁺-dependent dehydrogenases in glycolysis, TCA cycle, and oxidative phosphorylation.

Research areas. Cellular energy metabolism, sirtuin biology and epigenetic regulation, PARP enzyme and DNA repair research, mitochondrial function, NAD⁺ homeostasis and aging biology, circadian rhythm biology, NAD⁺ biosynthesis pathway research, metabolic regulation.

Available quantities. 500mg and 1000mg per vial.

Physical form. Supplied as a powder in a sealed research vial.

Purity. Greater than 99%, confirmed by HPLC and analytical characterisation at the batch level.

Analytical documentation. A batch-specific Certificate of Analysis is available on the Longevia Research website, covering compound identity, purity, and lot traceability.

Research-use classification. For laboratory research use only. Not for human or veterinary use, clinical diagnostics, or any therapeutic application.

NAD⁺ as Coenzyme and Signaling Substrate

NAD⁺ occupies a dual role in cellular biology — as a hydride-transfer coenzyme in oxidation-reduction reactions and as a substrate consumed by NAD⁺-dependent signaling enzymes. In its coenzyme role, NAD⁺/NADH cycling drives the TCA cycle, glycolysis, and oxidative phosphorylation — the central ATP-generating pathways of cellular energy metabolism. In its signaling substrate role, NAD⁺ is cleaved by sirtuins, PARPs, and CD38/CD157, generating nicotinamide and ADP-ribose products that regulate protein deacetylation, DNA repair signaling, and calcium signaling respectively. The total cellular NAD⁺ pool must support both roles, creating a research framework for understanding how NAD⁺ availability influences both energy metabolism and signaling pathway activity simultaneously.

Sirtuin Biology Research

Sirtuins (SIRT1–7) are NAD⁺-dependent protein deacylases that remove acyl modifications — primarily acetyl groups — from lysine residues on histones and other proteins, linking NAD⁺ availability to epigenetic regulation, mitochondrial function, and stress response signaling. Research has examined sirtuin activity in relation to cellular NAD⁺ concentration, establishing that sirtuin activity is sensitive to fluctuations in NAD⁺ availability — a finding that has generated substantial research interest in NAD⁺ homeostasis as a potential regulator of sirtuin-mediated biology. Cell-based and animal studies have investigated SIRT1, SIRT3, and other sirtuin family members in metabolic regulation, mitochondrial biogenesis, DNA repair, and aging biology. These are experimental findings in defined research systems.

PARP Enzyme and DNA Repair Research

PARP1 and PARP2 are NAD⁺-consuming enzymes that catalyse the addition of poly(ADP-ribose) chains to target proteins in response to DNA strand breaks — a primary DNA damage response mechanism. PARP activation consumes substantial quantities of NAD⁺ under conditions of DNA damage, potentially depleting cellular NAD⁺ pools in high-damage scenarios. Research examining the relationship between NAD⁺ availability, PARP activity, and DNA repair outcomes has used NAD⁺ as both a substrate reference and a supplement in cell-based DNA damage research systems.

NAD⁺ Decline and Aging Biology Research

Human observational and animal studies have reported declining NAD⁺ levels with aging in multiple tissues — including skeletal muscle, liver, and brain — in defined study populations and animal experimental systems. Research has investigated potential mechanisms including increased CD38 NADase activity, reduced NAD⁺ biosynthesis, and increased PARP consumption in aging cells. These observational and mechanistic findings provide the biological context for research into NAD⁺ homeostasis as an aging biology research topic. The relationship between NAD⁺ supplementation and aging-associated endpoints in experimental systems remains an active area of investigation.

NAD⁺ Biosynthesis Pathways

Cellular NAD⁺ is maintained through three biosynthesis routes: the Preiss-Handler pathway (from nicotinic acid/niacin); the de novo synthesis pathway (from tryptophan); and the salvage pathway (from nicotinamide, NMN, or NR). Research examining these pathways uses NAD⁺ as both a product reference standard and a direct substrate in reconstituted enzyme assay systems. The NNMT inhibitor 5-Amino-1MQ — also available in the Longevia Research catalog — operates at the intersection of the salvage pathway by competing with nicotinamide for NNMT-mediated methylation, illustrating the interconnected research context for NAD⁺ pathway biology.

Reliable research begins with accurately characterised material. For NAD⁺, the critical quality parameters are chemical identity — confirming NAD⁺ (oxidised form) rather than NADH, NADP⁺, or degradation products including ADP-ribose and nicotinamide — and purity, since NAD⁺ is susceptible to hydrolysis under acidic conditions and heat, generating ADP-ribose and nicotinamide as breakdown products that can interfere with enzyme kinetics assays.

Purity assessment. Each production lot is characterised to greater than 99% purity by HPLC. Chromatographic purity data is reported on the batch Certificate of Analysis.

Identity confirmation. Compound identity confirming the oxidised NAD⁺ form — distinct from NADH, NADP⁺, and hydrolysis products — is confirmed by analytical characterisation at the batch level. The batch COA confirms identity and purity data for the supplied material.

Batch traceability and Certificate of Analysis. Every vial of NAD⁺ 500mg and 1000mg is traceable to a specific production lot. A batch-specific Certificate of Analysis is accessible directly on the Longevia Research website, covering purity, identity, and lot information. Researchers evaluating this material for enzyme kinetics or cell-based assay work are encouraged to review the current batch documentation before use.

Handling. NAD⁺ is susceptible to hydrolytic degradation under acidic conditions and elevated temperatures. This material should be stored under conditions that minimise moisture and heat exposure, handled by qualified personnel using appropriate laboratory technique, and aliquoted appropriately to prevent repeated freeze-thaw cycling of the bulk material, consistent with institutional protocols for research-grade nucleotide coenzymes.

Longevia Research supplies NAD⁺ 500mg and 1000mg for laboratory and analytical research use only. The product is intended for use by qualified researchers and trained laboratory personnel in appropriate controlled research environments.

NAD⁺ is a naturally occurring coenzyme supplied strictly as a research tool. It is not a drug, not a dietary supplement, not a food additive, and not a cosmetic in this formulation. While NAD⁺ precursors including NMN and NR are marketed as dietary supplements in the US, and while intravenous NAD⁺ is used in certain clinical contexts, the Longevia Research research vial carries no such designation and has not been evaluated by any regulatory authority for safety or efficacy in this formulation.

Longevia provides no dosing instructions, administration guidance, treatment protocols, or reconstitution recommendations for human or veterinary use. The scientific literature summarised on this product page describes experimental observations in defined biochemical, cell-based, and animal research systems. Those findings are not medical claims and should not be interpreted as evidence of human efficacy, human safety, or fitness for any clinical application from this product.

The purchaser assumes full responsibility for lawful acquisition, handling, storage, use, and disposal of this material, and for compliance with all applicable local, state, federal, and institutional regulations. By purchasing this product, the buyer confirms that it will be used solely for legitimate laboratory research purposes by qualified personnel, and that its acquisition and intended use comply with applicable laws in the buyer's jurisdiction.