Coenzyme I (NAD), known as nicotinamide adenine two nucleoglycine or two phosphate glucoside, exists in two states of NAD+ and NADH in mammals, and is an important coenzyme in the redox reaction of human body. At the same time, it is the only substrate for the coenzyme I consuming enzyme (such as NAD+ dependent ADP ribonucleotransferase). These enzymes can only facilitate the decomposition of coenzyme I (NAD+) into ADP ribose and nicotinamide (Nam) as substrates, and play different physiological functions in different cells. This kind of enzyme mainly has three kinds of [1] [2] in the body.
1.ADP ribosyl transferase or poly ribonucleic polymerase (PARP):
These enzymes are involved in DNA repair, gene expression, cell cycle progression, cell survival, chromosome reconstruction and gene stability.
2. ring ADP ribose synthase (cADPR synthases) ribose polymerase (cADP synthase):
It is composed of a pair of extracellular enzyme, called lymphocyte antigen CD38 and CD157. They produce ring ADP ribose (important calcium signal (calcium signaling) messenger with NAD as substrate). It has important physiological significance in the maintenance of calcium homeostasis and immune response.
3, III protein lysine deacetylase Sirtuins:
They are a class of histone deacetylase, which have 7 different subtypes (SIRT1-SIRT7), which play an important role in cell resistance, energy metabolism, cell apoptosis and aging. A large number of studies have shown that the regulation of metabolic balance by Sirtuins will directly affect various metabolic related diseases, such as SIRT1, which regulates the state of histone acetylation in the favor of coenzyme I (NAD), and plays an important role in enhancing the oxidative stress response of the heart, regulating the metabolism of myocardial energy and resisting senescence.