NAD+ Peptide

NAD+ is one of the most important molecules in cell biology. It works as an electron carrier, picking up electrons from nutrients during metabolic reactions (glycolysis, the citric acid cycle, oxidative phosphorylation) and delivering them to the mitochondria where they are used to generate ATP, the cell's energy currency. When NAD+ picks up electrons, it becomes NADH. The ratio of NAD+ to NADH is a key indicator researchers use to assess a cell's metabolic state.

But NAD+ does more than shuttle electrons. It is also consumed (not just used, actually used up) by two important enzyme families. Sirtuins are enzymes that remove chemical tags from proteins and regulate gene activity, and they require NAD+ to function. PARP enzymes use NAD+ during DNA repair. When these enzymes are highly active, they can drain NAD+ levels inside the cell, creating competition between energy production and these other critical functions.

Researchers have found that NAD+ levels in tissues appear to decline with age in animal models, which has made it a focal point of aging and metabolism research. Scientists also study the pathways cells use to make NAD+, including the salvage pathway (recycling nicotinamide) and de novo synthesis (building it from the amino acid tryptophan), to understand how cells maintain their supply. With over 60,000 published papers, NAD+ is one of the most extensively studied molecules in all of biochemistry. For Research Use Only. Not intended for human or veterinary use.