Image from: http://www.indstate.edu/thcme/mwking/vitamins.html
(Inset photo is NADH)
NAD, which stands for Nicotinamide Adenine Dinucleotide is an electron carrier in processes throughout living organisms. Electron carriers are most commonly known as Coenzymes. NAD has a reduced form which is called NADH, and is the product of NAD taking two hydrogen atoms from a substrate with the assistance of an enzyme known as dehydrogenases. The general form of an oxidation-reduction reaction such as the one described above is:
How is NAD Created?
NAD dervies from the Vitamin Niacin which derives from Tryptophan the whole cycle can be seen in the image below.
(http://lpi.oregonstate.edu/infocenter/vitamins/niacin/parp.html)
We can see that NAD fucntions as an enzyme but where does it function?
One place we see NAD functioning is in Glycolysis, which is the releasing of ATP from glucose in the absence of oxygen. In this process glucose reacts with NAD to produce pyruvic acid which contains a lesser amount of energy. The difference from the begining of the process to the end is transferred to create ATP. The pyruvic acid is then sent throughout the cells/body and broken back down to reform NAD.
Image From: (http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/G/Glycolysis.html)
Another Place where NAD functions is in Cellular Respiration. This is where NAD enters the Kreb's Cycle or Citric Acid Cycle to help produce ATP for the cells. As you can see NAD has important role in producing energy in every living cell in the human body.
!GO --- NAD!
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