Background:

NAD+ is a coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage.

NAD+ is a coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. NAD+ is the oxidized form of NADH[1]. NAD+ is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (Nadide) [2].

Oral NAD+ supplementation has been used to combat simple fatigue as well as such mysterious and energy-sapping disorders as chronic fatigue syndrome and fibromyalgia[3].

参考文献:
[1]. Viollet, B., et al., Cellular and molecular mechanisms of metformin: an overview. Clin Sci (Lond), 2012. 122(6): p. 253-70.
[2]. Brandt, U., Energy converting NADH:quinone oxidoreductase (complex I). Annu Rev Biochem, 2006. 75: p. 69-92.
[3]. Kussmaul, L. and J. Hirst, The mechanism of superoxide production by NADH:ubiquinone oxidoreductase (complex I) from bovine heart mitochondria. Proc Natl Acad Sci U S A, 2006. 103(20): p. 7607-12.