Abstract
The body depends on NAD to indicate/sense the energy levels in the body. When energy is normal, sirtuins respond to fluctuations in energy demands and regulate gene transcription. When the body is under an oxidative challenge, poly(ADPribose) polymerase responds to DNA strand breaks and increases the activities of DNA repair enzymes. NAD and ATP are closely linked in the cell since they are both highenergy adenine nucleotides and are mutually required for their own synthesis.
Keywords: Exercise, Poly(ADP-ribose) Polymerase, NAD, NADPH Oxidase, NADH Oxidase, Nicotinamide, Sirtuin.