Nicotinic acid adenine dinucleotide

The result of this biosynthesis is that the product is nicotinic acid mononucleotide rather than free nicotinic acid. Ingested nicotinic acid is converted to nicotinic acid mononucleotide which, in turn, is converted to nicotinic acid adenine dinucleotide. Nicotinic acid adenine dinucleotide is then converted to nicotinamide adenine dinucleotide. If excess nicotinic acid is ingested, it is metabolized into a series of detoxification products (Fig. 4). Physiological metabohtes include /V-methylnicotinamide (19) and A/-methyl-6-pyridone-2-carboxamide (24) (1). 

NADP can be converted to nicotinic acid adenine dinucleotide phosphate (NAADP), which has distinct functions in the regulation of intracellular calcium stores. The studies of these new roles of NAD(P) in metabolism are in their early stages, but they might soon help to better understand and explain the symptoms of niacin deficiency ( pellagra) [1]. 

Brailoiu, E., Patel, S. and Dun, N. J. Modulation of spontaneous transmitter release from the frog neuromuscular junction by interacting intracellular Ca2+ stores critical role for nicotinic acid-adenine dinucleotide phosphate (NAADP). Biochem. J. 373 313-318, 2003. 

LEMS Lambert-Eaton myasthenic syndrome NAADP nicotinic acid-adenine dinucleotide phosphate... 

Yusufi ANK, Cheng J, Thompson MA, Chini EN, Grande JP 2001 Nicotinic acid-adenine dinucleotide phosphate (NAADP) elicits specific microsomal Ca2+ release from mammalian cells. Biochem J 353 531—536... 

In smooth muscle, just as in other cells, extracellular stimuli typically evoke an increase in cytosolic Ca2+ concentration ([Ca2+]c) by stimulating release of Ca2+ from intracellular stores or Ca2+ entry across the plasma membrane. Members of two closely related families of intracellular Ca2+ channels, ryanodine receptors and the receptors for inositol-1,4,5-trisphosphate (InsP3) appear to be expressed in all smooth muscle cells and they provide the most important route for release of Ca2+ from the sarcoplasmic reticulum (Sutko Airey 1996). The roles of additional Ca2+-mobilizing messengers, such as nicotinic acid adenine dinucleotide... 

Nicotinic acid adenine dinucleotide phosphate (NAA 315 Nicotinic acid hydroxylase 825 Nidogen 437 Ninhydrin 120,121s Nitrate reductase(s)... 

NAADP = Nicotinic Acid Adenine Dinucleotide Phosphate... 

NAD(P)H nicotinic acid adenine dinucleotide (phosphate), reduced form NMR nuclear magnetic resonance (spectroscopy)... 

The most generally interesting intracellular metabolites are the adenine nucleotide phosphates (ATP/ADP/AMP) and the nicotinic acid/adenine dinucleotide phosphates (NAD(P)H/NAD(P)). The pool concentrations and ratios of these can serve as markers for the physiological status of a culture. 

Nicotinic acid adenine dinucleotide 2 -phosphate (= NAADP)... 

NAADP, nicotinic acid adenine dinucleotide 2 -phosphate NAADP-R, nicotinic acid adenine dinucleotide 2 -phosphate receptor nACh-R, nicotinic acetylcholine receptor NADH DH, NADH dehydrogenase NADH/NAD"1", reduced/oxidized nicotinamide adenine dinucleotide NADH-U() OR, NADH-ubiquinone oxidoreductase... 

Navazio, L., Bewell, M.A., Siddiqua, A., Dickinson, G.D., Galione, A., and Sanders, D., 2000, Calcium release from the endoplasmic reticulum of higher plants elicited by the NADP metabolite nicotinic acid adenine dinucleotide phosphate. Proc. Natl. Acad. Sci. USA. 97 8693-8698. 

Retinoids in Transmembrane Signaling Neutrophils treated with physiological concentrations of all-tra s-retinoic acid show a dose-dependent increase in synthesis of superoxide. Inhibitor studies suggest that retinoic acid acts via an inositol trisphosphate cascade rather than calcium and protein kinase C (Koga et al., 1997). There is also evidence that all-rrans-retinoic acid leads to increased formation of cADP-ribose and nicotinic acid adenine dinucleotide phosphate as second messengers (Section 8.4.4 Dousa et al., 1996 Mehta and Cheema, 1999). 

The nicotinamide nucleotide coenzymes function as electron carriers in a wide variety of redox reactions. In addition, NAD is the precursor of adenine dinucleotide phosphate (ADP)-ribose for ADP-ribosylation and poly(ADP-ribosylation) of proteins and cADP-ribose and nicotinic acid adenine dinucleotide phosphate (NAADP). They act as second messengers and stimulate increases in intracellular calcium concentrations. 

NAD is the source of ADP-ribose for the modification of proteins by mono-ADP-ribosylation, catalyzed by ADP-ribosyltransferases (Section 8.4.2), and poly(ADP-ribosylation), catalyzed by poly(ADP-ribose) polymerase (Section 8.4.3). It is also the precursor of two second messengers that act to increase the intracellular concentration of calcium, cADP-ribose, and nicotinic acid adenine dinucleotide phosphate (Section 8.4.4). 

Figure 8.7. Reactions catalyzed byADP ribose cyclase (NAD glycohydrolase, EC 3.2.2.5). When the substrate is NADP, the base exchange reaction leads to the formation of nicotinic acid adenine dinucleotide phosphate.

Wilson HL and Galione A (1998) Differential regulation of nicotinic acid-adenine dinucleotide phosphate and cADP-ribose production by cAMP and cGMP. Biochemical Journal331, 837-43. 

It is eilso the precursor of two second messengers that act to increase the intracellular concentration of calcium, cADP-ribose, tmd nicotinic acid adenine dinucleotide phosphate (Section 8.4.4). 

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