Nicotinamide adenine dinucleotide salvage pathway

The **nicotinamide adenine dinucleotide salvage pathway** is a major cellular route to regenerate NAD⁺ from nicotinamide produced as a byproduct of NAD⁺-consuming reactions such as sirtuin- and PARP-mediated processes[1][2][3][5]. The pathway involves key enzymes including **nicotinamide phosphoribosyltransferase (NAMPT)**, which catalyzes the conversion of nicotinamide to nicotinamide mononucleotide (NMN), and **nicotinamide mononucleotide adenylyltransferases (NMNAT1-3)**, which convert NMN to NAD⁺[1][2][3][5]. The pathway is critical for sustaining NAD⁺ levels, especially in tissues with high NAD⁺ turnover, and is increasingly recognized as a target for intervention in cancer, aging, and metabolic disease[1][2][3][5].

Other names

NAD⁺ salvage pathwayNAD salvage

Inhibition of NAD⁺ salvage pathway enzymes (esp. NAMPT) depletes cellular NAD⁺, impacting cellular metabolism. Supplementation with NAD⁺ precursors (e.g., NR, NMN) can boost NAD⁺ levels by feeding into the salvage pathway.