Skip to main content
. 2020 May 14;9(5):425. doi: 10.3390/antiox9050425

Figure 1.

Figure 1

NAD+ biosynthesis pathways. The kynurenine pathway represents the de novo pathway of NAD+ is synthesis from catabolism of the amino acid tryptophan. NAD+ can also be synthesised via salvage of nicotinamide, nicotinic acid, nicotinic acid riboside and nicotinamide riboside form of vitamin B3. Abbreviations: NR kinase, nicotinamide riboside kinase; NAMPT, nicotinamide phosphoribosyltransferase; NMNAT, nicotinamide mononucleotide adenyltransferase; NAPRT, nicotinic acid phosphoribosyltransferase; PNP, purine nucleoside phosphorylase.