Nicotinamide Adenine Dinucleotide (NAD) is a cozyme found in all living cells, located at the center of adenine dinucleotide metabolism. It plays a crucial role in the biochemical processes that generate energy through the oxidation of nutrients. NAD is also crucial for DNA repair, cell signaling, regulation of gene expression and, calcium signaling. NAD is called a dinucleotide because it consists of two nucleotides joined through phosphate groups. NAD exists in two forms: NAD+ and NADH. The "+" or "H" indicates the molecule's oxidation state; NAD+ is the oxidized form, while NADH is the reduced form.
Molecular Formula: C21H27N7O14P2
Molecular Weight: 663.4 g/mol
PubChem CID: 5892
CAS Number: 53-84-9
Synonyms: Beta-nicotinamide adenine dinucleotide, Dihydronicotinamide Adenine Dinucleotide, Nicotinamide-Adenine Dinucleotide
In metabolism, nicotinamide adenine dinucleotide takes part in redox reactions that transport electrons from one reaction to another. Therefore, the cofactor is found in two forms in cells; NAD+ is an oxidizing agent and accepts (-) electrons from other molecules and is reduced. This reaction forms NADH, which can then be used as a reducing agent to donate electrons. These electron transfer reactions are the main process of NAD.
NAD is vital for several cellular processes:
Energy Metabolism: NAD+ plays a central role in metabolism, acting as a carrier for electrons in the electron transport chain, which is a series of reactions that generate ATP, the primary energy currency of the cell.
DNA Repair and Cell Signaling: It also functions in DNA repair and as a signaling molecule, participating in the activation of enzymes that may influence aging and disease.
Regulation of Gene Expression: NAD+ is involved in the regulation of gene expression through its role as a substrate for enzymes like sirtuins and ADP-ribosyltransferases, which modulate the activity of proteins by removing or adding ADP-ribose units.
Calcium Signaling: NAD+ and its derivatives are also involved in calcium signaling pathways that are crucial for cellular responses to external stimuli.
Since NAD+ levels in the body decrease with age, it can have an impact on health and longevity. The relationship between the decrease in NAD+ levels in the body and age-related degenerative diseases is being intensively researched by scientists. This increases interest in strategies and NAD + supplements to increase NAD + levels to delay aging and solve age-related health problems. Increasing NAD+ levels in cells will continue to be examined as a potential anti-aging strategy.
