NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in every living cell and one of the most studied molecules in cellular biology. Its central role in energy metabolism, DNA repair and cell signalling has made it a major focus of longevity and ageing research. This profile covers its biological role, key research areas and considerations for laboratory sourcing.
What is NAD+?
NAD+ is a dinucleotide coenzyme consisting of two nucleotides joined by phosphate groups. It exists in oxidised (NAD+) and reduced (NADH) forms, cycling between them as it transfers electrons in metabolic reactions. Beyond its role as a redox carrier, NAD+ serves as a substrate for several classes of enzymes — most notably sirtuins and PARPs — that are central to DNA repair, gene expression regulation and cellular stress responses.
Role in cellular energy metabolism
NAD+ is essential for glycolysis, the TCA cycle and oxidative phosphorylation — the core pathways of cellular energy production. In each of these processes, NAD+ accepts electrons (becoming NADH), which are then used by the mitochondrial electron transport chain to generate ATP. Without adequate NAD+, these pathways slow, reducing cellular energy availability. This metabolic centrality is one reason NAD+ levels are studied as a marker of cellular health and metabolic capacity.
Sirtuin and PARP interactions
The non-redox roles of NAD+ are perhaps more relevant to longevity research. Sirtuins (SIRT1–7) are NAD+-dependent deacetylases that regulate gene expression, DNA repair, mitochondrial biogenesis and stress responses. PARP enzymes consume NAD+ as part of the DNA damage repair response. Both enzyme classes compete for the same NAD+ pool, and their relative activity is studied as a determinant of cellular ageing trajectories. Research into NAD+ precursors and supplementation largely targets this axis.
Longevity and ageing research
NAD+ levels decline with age in most tissues studied, and this decline is associated with reduced sirtuin activity and impaired DNA repair capacity in preclinical models. Restoring NAD+ levels in aged animals has been studied for effects on metabolic function, physical performance and lifespan in several model organisms. NAD+ sits at the intersection of metabolism, epigenetics and ageing biology — making it one of the more versatile tools in longevity research. For related compounds, see SS-31 and Epithalon in the longevity category.
Purity and stability in research
NAD+ is sensitive to light, heat and moisture, and degrades to inactive forms under suboptimal conditions. Research-grade material should be characterised by HPLC for purity and identity, and stored in lyophilised form under appropriate conditions. Every NAD+ batch Pepreta supplies is tested by HPLC with a Certificate of Analysis, and supplied as lyophilised powder in quantities from 100mg to 1000mg.
Sourcing NAD+ for research
Pepreta supplies NAD+ as lyophilised powder in 100mg, 500mg and 1000mg vials, dispatched from Sydney and Melbourne. For reconstitution guidance see our reconstitution guide. Supplied for laboratory and research use only — not for human or animal consumption.