Target type: biologicalprocess
The chemical reactions and pathways involving nicotinamide adenine dinucleotide (NAD), a coenzyme present in most living cells and derived from the B vitamin nicotinic acid. [GOC:jl, ISBN:0618254153]
NAD metabolic process encompasses a series of biochemical reactions that involve the synthesis, degradation, and utilization of nicotinamide adenine dinucleotide (NAD). NAD is a crucial coenzyme involved in numerous metabolic pathways, playing a vital role in energy production, redox reactions, and signaling cascades. The NAD metabolic process can be broadly categorized into two main stages: NAD biosynthesis and NAD degradation.
**NAD biosynthesis:**
* **De novo synthesis:** This pathway involves the conversion of tryptophan or nicotinic acid (niacin) into nicotinamide mononucleotide (NMN). NMN is then phosphorylated to NAD by the enzyme NMN adenylyltransferase.
* **Precursor salvage pathway:** This pathway utilizes pre-existing nicotinamide, nicotinic acid, or nicotinamide riboside to produce NAD. These precursors are salvaged and converted to NAD through specific enzymatic reactions.
**NAD degradation:**
* NAD is degraded into nicotinamide, which can be recycled back into the biosynthesis pathway.
* NAD can also be hydrolyzed to nicotinamide riboside and adenosine diphosphate ribose (ADPR). ADPR can be further metabolized into ADP-ribose, a signaling molecule involved in various cellular processes.
**Functions of NAD:**
* **Redox reactions:** NAD acts as an electron carrier in numerous redox reactions, including glycolysis, the citric acid cycle, and oxidative phosphorylation. It shuttles electrons between different metabolic pathways, facilitating energy production.
* **DNA repair:** NAD is a substrate for poly(ADP-ribose) polymerase (PARP), an enzyme involved in DNA damage repair. PARP utilizes NAD to generate poly(ADP-ribose) chains, which contribute to the repair process.
* **Signaling pathways:** NAD is involved in various signaling pathways, including the regulation of calcium homeostasis, apoptosis, and cell proliferation.
**Regulation of NAD metabolism:**
* NAD levels are tightly regulated by various factors, including nutritional intake, metabolic stress, and hormonal signals.
* Enzymes involved in NAD biosynthesis and degradation are subject to regulation by various mechanisms, ensuring optimal NAD levels for cellular function.
**Clinical implications:**
* NAD metabolism is linked to various diseases, including cancer, neurodegenerative disorders, and metabolic diseases.
* Therapeutic strategies targeting NAD metabolism are being investigated for the treatment of these diseases.
Overall, NAD metabolic process plays a critical role in maintaining cellular function and homeostasis. Its intricate regulation ensures the optimal availability of NAD for various metabolic pathways and signaling cascades, highlighting its importance in human health.'
"
Protein | Definition | Taxonomy |
---|---|---|
ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 1 | An ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 1 that is encoded in the genome of human. [PRO:WCB, UniProtKB:P28907] | Homo sapiens (human) |
ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 1 | An ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 1 that is encoded in the genome of human. [PRO:WCB, UniProtKB:P28907] | Homo sapiens (human) |
L-lactate dehydrogenase B chain | An L-lactate dehydrogenase B chain that is encoded in the genome of human. [PRO:DNx, UniProtKB:P07195] | Homo sapiens (human) |
NAD kinase | An NAD kinase that is encoded in the genome of human. [PRO:DNx, UniProtKB:O95544] | Homo sapiens (human) |
Kynurenine 3-monooxygenase | A kynurenine 3-monooxygenase that is encoded in the genome of human. [PRO:DNx, UniProtKB:O15229] | Homo sapiens (human) |
Compound | Definition | Classes | Roles |
---|---|---|---|
taxifolin | 3'-hydroxyflavanones; 4'-hydroxyflavanones; dihydroflavonols; pentahydroxyflavanone; secondary alpha-hydroxy ketone | ||
oxamic acid | oxamic acid : A dicarboxylic acid monoamide resulting from the formal condensation of one of the carboxy groups of oxalic acid with ammonia. Oxamic Acid: Amino-substituted glyoxylic acid derivative. | dicarboxylic acid monoamide | Escherichia coli metabolite |
catechin | hydroxyflavan | ||
gossypol | Gossypol: A dimeric sesquiterpene found in cottonseed (GOSSYPIUM). The (-) isomer is active as a male contraceptive (CONTRACEPTIVE AGENTS, MALE) whereas toxic symptoms are associated with the (+) isomer. | ||
guanidine hydrochloride | one-carbon compound; organic chloride salt | protein denaturant | |
1-hydroxy-2-naphthoic acid | 1-hydroxy-2-naphthoic acid : A naphthoic acid with the carboxy group at position 2 and carrying a hydroxy substituent at the 1-position. It is a xenobiotic metabolite produced by the biodegradation of phenanthrene by microorganisms. 1-hydroxy-2-naphthoic acid: RN given refers to parent cpd | hydroxy monocarboxylic acid; naphthoic acid; naphthols | bacterial xenobiotic metabolite; fungal xenobiotic metabolite |
2,4-pyridinedicarboxylic acid | lutidinic acid : A pyridinedicarboxylic acid carrying carboxy groups at positions 2 and 4. | pyridinedicarboxylic acid | |
epigallocatechin gallate | (-)-epigallocatechin 3-gallate : A gallate ester obtained by the formal condensation of gallic acid with the (3R)-hydroxy group of (-)-epigallocatechin. epigallocatechin gallate: a steroid 5alpha-reductase inhibitor and antimutagen in green tea (Camellia sinensis) | flavans; gallate ester; polyphenol | antineoplastic agent; antioxidant; apoptosis inducer; geroprotector; Hsp90 inhibitor; neuroprotective agent; plant metabolite |
gallocatechol | (-)-epigallocatechin : A flavan-3,3',4',5,5',7-hexol having (2R,3R)-configuration. | catechin; flavan-3,3',4',5,5',7-hexol | antioxidant; food component; plant metabolite |
gossylic nitrile-1,1'-diacetate | gossylic nitrile-1,1'-diacetate: inhibits human immunodeficiency virus Type I replication; structure given in first source | ||
(3-nitrobenzoyl)alanine | (3-nitrobenzoyl)alanine: inhibits kynurenine hydroxylase; structure in first source | ||
delphinidin | delphinidin : An anthocyanidin cation consisting of benzopyrylium with hydroxy substituents at the 3-, 5- and 7-positions and a 3,4,5-trihydroxyphenyl group at the 2-position. It is a plant pigment responsible for the colours of the plants of the genera Viola and Delphinium. delphinidin: RN given refers to parent cpd; | 5-hydroxyanthocyanidin | antineoplastic agent; biological pigment; plant metabolite |
cyanidin | cyanidin cation : An anthocyanidin cation that is flavylium substituted at positions 3, 3', 4', 5 and 7 by hydroxy groups. cyanidin: RN given refers to parent cpd; structure | 5-hydroxyanthocyanidin | antioxidant; metabolite; neuroprotective agent |
benzamide adenine nucleotide | benzamide adenine nucleotide: structure given in first source | ||
tecadenoson | tecadenoson: an A1 adenosine receptor agonist | ||
malvidin | malvidin : An anthocyanidin cation that is delphinidin carrying methyl substituents at positions 3' and 5'. malvidin: RN given refers to parent cpd; coloring agent from flowers of Malvaviscus conzatti | 5-hydroxyanthocyanidin | biological pigment; metabolite |
pelargonidin | pelargonidin : An anthocyanidin cation that is flavylium substituted by a hydroxy groups at positions 3, 5, 7 and 4'. pelargonidin: influences flower phenotype | 5-hydroxyanthocyanidin | plant metabolite |
cyanidin 3-o-beta-d-glucopyranoside | cyanidin 3-O-beta-D-glucoside : An anthocyanin cation that is a cyanidin cation linked to a beta-D-glucosyl moiety at position 3. | anthocyanin cation; beta-D-glucoside; monosaccharide derivative | metabolite |
buclizine | luteolinidin: structure in first source | 5-hydroxyanthocyanidin | |
peonidin | peonidin : An anthocyanidin cation that is flavylium bearing four hydroxy substituents at positions 3, 4', 5 and 7 as well as a methoxy substituent at position 3'. peonidin: a COX-2 inhibitor with protein kinase inhibitory and phytogenic antineoplastic activities; RN given for chloride salt | 5-hydroxyanthocyanidin | antineoplastic agent; antioxidant; apoptosis inducer; metabolite |
petunidin | petunidin : An anthocyanidin cation that is flavylium bearing five hydroxy substituents at positions 3, 3', 4', 5 and 7 as well as a methoxy substituent at position 5'. petunidin: RN given for chloride salt | 5-hydroxyanthocyanidin | plant metabolite |
resveratrol | trans-resveratrol : A resveratrol in which the double bond has E configuration. | resveratrol | antioxidant; phytoalexin; plant metabolite; quorum sensing inhibitor; radical scavenger |
3,3',4,5'-tetrahydroxystilbene | 3,3',4,5'-tetrahydroxystilbene: demethyl derivative of isorhapontigenin; structure in first source; a Syk kinase inhibitor; found in heartwood of FABACEAE; inhibitor of photosynthesis in spinach chloroplasts; may be inhibitor of plant growth; RN given refers to (E)-isomer piceatannol : A stilbenol that is trans-stilbene in which one of the phenyl groups is substituted by hydroxy groups at positions 3 and 4, while the other phenyl group is substituted by hydroxy groups at positions 3 and 5. | catechols; polyphenol; resorcinols; stilbenol | antineoplastic agent; apoptosis inducer; geroprotector; hypoglycemic agent; plant metabolite; protein kinase inhibitor; tyrosine kinase inhibitor |
oxalylglycine | N-oxalylglycine : An amino dicarboxylic acid that is iminodiacetic acid with an oxo substituent. It is used as an inhibitor of alpha-ketoglutarate dependent (EC 1.14.11.*) enzymes. oxalylglycine: structure given in first source | amino dicarboxylic acid; N-acylglycine | EC 1.14.11.* (oxidoreductase acting on paired donors, 2-oxoglutarate as one donor, incorporating 1 atom each of oxygen into both donors) inhibitor |
ex 527 | 6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide : A member of the class of carbazoles that is 2,3,4,9-tetrahydro-1H-carbazole which is substituted at position 1 by an aminocarbohyl group and at position 6 by a chlorine. 6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide: structure in first source | carbazoles; monocarboxylic acid amide; organochlorine compound | |
quercetin | 7-hydroxyflavonol; pentahydroxyflavone | antibacterial agent; antineoplastic agent; antioxidant; Aurora kinase inhibitor; chelator; EC 1.10.99.2 [ribosyldihydronicotinamide dehydrogenase (quinone)] inhibitor; geroprotector; phytoestrogen; plant metabolite; protein kinase inhibitor; radical scavenger | |
luteolin | 3'-hydroxyflavonoid; tetrahydroxyflavone | angiogenesis inhibitor; anti-inflammatory agent; antineoplastic agent; apoptosis inducer; c-Jun N-terminal kinase inhibitor; EC 2.3.1.85 (fatty acid synthase) inhibitor; immunomodulator; nephroprotective agent; plant metabolite; radical scavenger; vascular endothelial growth factor receptor antagonist | |
myricetin | 7-hydroxyflavonol; hexahydroxyflavone | antineoplastic agent; antioxidant; cyclooxygenase 1 inhibitor; food component; geroprotector; hypoglycemic agent; plant metabolite | |
quercetagetin | quercetagetin : A hexahydroxyflavone that is flavone substituted by hydroxy groups at positions 3, 5, 6, 7, 3' and 4' respectively. quercetagetin: structure given in first source; inhibits aldose reductase in rat lens | flavonols; hexahydroxyflavone | antioxidant; antiviral agent; plant metabolite |
robinetin | robinetin : A pentahydroxyflavone that is flavone substituted by hydroxy groups at positions 3, 7, 3, 4' and 5'. robinetin: structure given in first source | 7-hydroxyflavonol; pentahydroxyflavone | plant metabolite |
ro 61-8048 | C-nitro compound | ||
3-dihydroxy-6-methyl-7-(phenylmethyl)-4-propylnaphthalene-1-carboxylic acid | 3-dihydroxy-6-methyl-7-(phenylmethyl)-4-propylnaphthalene-1-carboxylic acid: inhibits lactate dehydrogenase A | ||
adenosine monophosphate | adenosine 5'-monophosphate(2-) : A nucleoside 5'-monophosphate(2-) that results from the removal of two protons from the phosphate group of adenosine 5'-monophosphate (AMP). | nucleoside 5'-monophosphate(2-) | cofactor; fundamental metabolite; human metabolite |
galloflavin | galloflavin: structure in first source | ||
gossylic iminolactone | gossylic iminolactone: inhibits human immunodeficiency virus type I replication; structure given in first source | ||
gossylic lactone | gossylic lactone: inhibits human immunodeficiency virus type I replication; structure given in first source |