10.51 Niacin Functions

Approximately 200 enzymes require NAD or NADP+. We will go through some selected functions of NAD and NADP+. The following figures and legends show and describe the functions of NAD and NADP+.

Figure 10.511 NAD is required for glycolysis1

Figure 10.512 NAD is required for the transition reaction and at three different points in the citric acid cycle2

Figure 10.513 NAD is required for fatty acid oxidation

Figure 10.514 Alcohol oxidation; NAD is required by alcohol dehydrogenase, and the MEOS uses NADPH3,4

Figure 10.515 Fatty acid synthesis uses NADPH5

HMG CoA reductase, the rate-limiting enzyme in cholesterol synthesis, uses NADPH. NADPH is also used by the antioxidant enzyme glutathione reductase as shown in the link below6.

Web Link

The Glutathione Oxidation Reduction (Redox) Cycle

References & Links

1. http://en.wikipedia.org/wiki/File:CellRespiration.svg

2. http://en.wikipedia.org/wiki/File:Citric_acid_cycle_with_aconitate_2.svg

3. http://en.wikipedia.org/wiki/File:Ethanol_flat_structure.png

4. https://en.wikipedia.org/wiki/Acetaldehyde#/media/File:Acetaldehyde-2D-flat.svg

5. http://en.wikipedia.org/wiki/Mitochondrion

6. Gropper SS, Smith JL, Groff JL. (2008) Advanced nutrition and human metabolism. Belmont, CA: Wadsworth Publishing.


The Glutathione Oxidation Reduction (Redox) Cycle – http://lpi.oregonstate.edu/infocenter/minerals/selenium/gsh.html