NAD+ biosynthesis enzyme

NAD+ biosynthesis enzymes are a group of metabolic enzymes responsible for the production and recycling of nicotinamide adenine dinucleotide (NAD+) within cells. NAD+ is an essential molecule for energy metabolism, acting as an electron carrier in redox reactions, and serving as a co-substrate for key signaling molecules such as sirtuins and PARPs. The main biosynthetic pathways include the de novo route from tryptophan, the Preiss-Handler pathway from nicotinic acid, and the salvage pathway from nicotinamide, as well as recently identified routes using nicotinamide riboside and nicotinamide mononucleotide. Key enzymes include NAMPT, NAPRT, NMNAT, NRK, and QAPRTase. Dysregulation or upregulation of these enzymes is associated with cancer metabolism, age-related diseases, neurodegenerative disorders, and metabolic syndromes. Several drugs are under development or in clinical use targeting these enzymes, particularly to induce cancer cell death and modulate immune responses, but significant challenges remain in minimizing side effects and improving therapeutic selectivity[2][3][4][5][6][1][7].

Other names

NAD biosynthetic enzymeNAD+ synthetasenicotinamide phosphoribosyltransferase (NAMPT)nicotinic acid phosphoribosyltransferase (NAPRT)nicotinamide mononucleotide adenylyltransferase (NMNAT)nicotinamide riboside kinase (NRK)quinolinate phosphoribosyltransferase (QAPRTase)NMRK1/2

Inhibition of NAD+ biosynthesis (NAMPT inhibitors block the salvage pathway, decrease NAD+ levels, induce apoptosis in cancer cells) [2][3][4][5] - Boosting NAD+ levels (precursor supplementation increases NAD+, activates sirtuins, improves metabolism and longevity, protects against metabolic disease) [6] - Modulation of NAD+-dependent enzyme signaling (such as sirtuins or PARPs) - Interference with NAD+ redox reactions - Disruption of tumor metabolism and immune evasion (targeting NADase or biosynthesis inhibits tumor immunosuppressive microenvironment) [2]