NAD+

NAD+ (Nicotinamide Adenine Dinucleotide) is a critical coenzyme present in all living cells, serving as the central mediator of cellular energy metabolism and a substrate for several families of enzymes critical to health and longevity. As an electron carrier, NAD+ cycles between oxidized (NAD+) and reduced (NADH) forms to drive ATP production through glycolysis, the TCA cycle, and oxidative phosphorylation. Beyond energy metabolism, NAD+ serves as an essential substrate for three key enzyme families: sirtuins (SIRT1-7) — NAD+-dependent deacetylases that regulate gene expression, DNA repair, circadian rhythms, and mitochondrial biogenesis; PARPs (poly-ADP-ribose polymerases) — DNA repair enzymes that consume NAD+ during the damage response; and CD38/CD157 — ectoenzymes involved in calcium signaling and immune function. NAD+ levels decline by approximately 50% between ages 40 and 60 in human tissues, and this decline is increasingly recognized as a driver of age-related metabolic dysfunction, neurodegeneration, and cardiovascular disease. This high-purity research compound is used in studies on mitochondrial function restoration, sirtuin activation kinetics, PARP-mediated DNA repair capacity, circadian clock gene regulation, and cellular senescence reversal.