NAD+, the molecule aging research runs on.
Most research fields organize around a pathway or a disease. Aging biology, to a remarkable degree, organizes around a single molecule that every living cell already contains.
One molecule, two different jobs.
Nicotinamide adenine dinucleotide is ancient chemistry — a coenzyme present in every living cell, doing two jobs that could hardly be more different. Job one is redox: NAD+ accepts electrons from the breakdown of food (becoming NADH) and delivers them to the mitochondria to make ATP. In this job the molecule is recycled endlessly, a rechargeable battery for metabolism, and the NAD+/NADH ratio is one of biochemistry's most-used readouts of a cell's energetic state.
Job two is what put it at the center of aging research: NAD+ is a consumable substrate. Three enzyme families destroy it as they work — sirtuins, which regulate gene expression and stress responses; PARPs, which repair DNA damage; and CD38, an immune-linked enzyme that turns out to be one of the biggest NAD+ consumers of all. In this job the molecule is spent, not recycled, which makes cellular NAD+ a genuine resource under continuous demand.
The decline that launched a thousand studies.
Measured NAD+ levels fall substantially with age across tissues and species — one of the more robust observations in aging biology. The mechanism appears to be a supply-and-demand squeeze: consumption rises (CD38 expression climbs with age; accumulated DNA damage keeps PARPs busy) while the salvage pathway that recycles nicotinamide back into NAD+ fails to keep pace. Because sirtuins and PARPs are the cell's maintenance crews, a shrinking NAD+ budget means maintenance deferred — the hypothesis that connects the decline to aging phenotypes, and the field's central open question.
What researchers actually do with it.
- Enzymatic assays: countless biochemical assays use NAD+/NADH interconversion as their readout, making the coenzyme one of the most-consumed reagents in any life-science lab.
- Sirtuin and PARP studies: as the shared substrate, NAD+ availability is the lever for probing both families — restrict it, supplement it, or trace its consumption.
- Mitochondrial function work: respiration and metabolic-flux experiments where the redox couple is either the measurement or the manipulated variable.
- Salvage-pathway research: mapping how cells synthesize and recycle NAD+, and where the aging squeeze actually binds.
Bench realities.
NAD+ is chemistry with opinions. The powder is hygroscopic — it pulls water from the air — and in solution it degrades, faster when warm or alkaline. Bench discipline is accordingly strict: keep the powder sealed, dry and frozen; prepare solutions fresh, cold, and at neutral-to-slightly-acidic pH; and don't store what you can prepare on the day. Our storage guide covers the general discipline; NAD+ is one of the compounds that genuinely punishes shortcuts.
It's also why our NAD+ ships in 500 mg and 1000 mg vials — reagent quantities for a molecule used by the assay, not the microgram. Each batch is independently verified at 99%+ purity with identity confirmation and endotoxin screening, and pairs naturally with MOTS-c in mitochondria-focused designs: one compound is the organelle's energy currency, the other its outbound signal.
Common questions.
Different category entirely. Supplements are consumer products under food regulation; research-grade NAD+ is a laboratory reagent, sold for bench use with batch-level analytical documentation and no consumption claims of any kind.
Because it eats the budget. CD38 is among the most voracious NAD+-consuming enzymes, and its expression rises with age — making it a leading suspect for the age-related decline and one of the field's most active targets of study.
Sirtuins are NAD+-dependent enzymes — no NAD+, no sirtuin activity. That hard dependency is why NAD+ availability is the standard experimental lever in sirtuin research on gene regulation, metabolism and stress response.
