Reaction Process: Reactome:R-TGU-379401

Clearance of dopamine related metabolites

find 11 related metabolites which is associated with chemical reaction(pathway) Clearance of dopamine

DA + SAM ⟶ 3MT + SAH

Dopamine

alpha-(3,4-Dihydroxyphenyl)-beta-aminoethane

C8H11NO2 (153.0789746)


Dopamine is a member of the catecholamine family of neurotransmitters in the brain and is a precursor to epinephrine (adrenaline) and norepinephrine (noradrenaline). Dopamine is synthesized in the body (mainly by nervous tissue and adrenal glands) first by the hydration of the amino acid tyrosine to DOPA by tyrosine hydroxylase and then by the decarboxylation of DOPA by aromatic-L-amino-acid decarboxylase. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (dopamine receptors) mediates its action, which plays a major role in reward-motivated behaviour. Dopamine has many other functions outside the brain. In blood vessels, dopamine inhibits norepinephrine release and acts as a vasodilator (at normal concentrations); in the kidneys, it increases sodium excretion and urine output; in the pancreas, it reduces insulin production; in the digestive system, it reduces gastrointestinal motility and protects intestinal mucosa; and in the immune system, it reduces the activity of lymphocytes. Parkinsons disease, a degenerative condition causing tremor and motor impairment, is caused by a loss of dopamine-secreting neurons in an area of the midbrain called the substantia nigra. There is evidence that schizophrenia involves altered levels of dopamine activity, and most antipsychotic drugs used to treat this are dopamine antagonists, which reduce dopamine activity. Attention deficit hyperactivity disorder, bipolar disorder, and addiction are also characterized by defects in dopamine production or metabolism. It has been suggested that animals derived their dopamine-synthesizing machinery from bacteria via horizontal gene transfer that may have occurred relatively late in evolutionary time. This is perhaps a result of the symbiotic incorporation of bacteria into eukaryotic cells that gave rise to mitochondria. Dopamine is elevated in the urine of people who consume bananas. When present in sufficiently high levels, dopamine can be a neurotoxin and a metabotoxin. A neurotoxin is a compound that disrupts or attacks neural tissue. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of dopamine are associated with neuroblastoma, Costello syndrome, leukemia, phaeochromocytoma, aromatic L-amino acid decarboxylase deficiency, and Menkes disease (MNK). High levels of dopamine can lead to hyperactivity, insomnia, agitation and anxiety, depression, delusions, excessive salivation, nausea, and digestive problems. A study has shown that urinary dopamine is produced by Bacillus and Serratia (PMID: 24621061) Occurs in several higher plants, such as banana (Musa sapientum). As a member of the catecholamine family, dopamine is a precursor to norepinephrine (noradrenaline) and then epinephrine (adrenaline) in the biosynthetic pathways for these neurotransmitters. Dopamine is elevated in the urine of people who consume bananas. Dopamine is found in many foods, some of which are garden onion, purslane, garden tomato, and swiss chard. Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80\% of the catecholamine content in the brain. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical, L-DOPA, which is synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons (nerve cells) to send signals to other nerve cells. Neurotransmitters are synthesized in specific regions of the brain, but affect many regions systemically. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain,[4] and many addictive drugs increase dopamine release or block its reuptake into neurons following release.[5] Other brain dopamine pathways are involved in motor control and in controlling the release of various hormones. These pathways and cell groups form a dopamine system which is neuromodulatory.[5] In popular culture and media, dopamine is often portrayed as the main chemical of pleasure, but the current opinion in pharmacology is that dopamine instead confers motivational salience;[6][7][8] in other words, dopamine signals the perceived motivational prominence (i.e., the desirability or aversiveness) of an outcome, which in turn propels the organism's behavior toward or away from achieving that outcome.[8][9] Outside the central nervous system, dopamine functions primarily as a local paracrine messenger. In blood vessels, it inhibits norepinephrine release and acts as a vasodilator; in the kidneys, it increases sodium excretion and urine output; in the pancreas, it reduces insulin production; in the digestive system, it reduces gastrointestinal motility and protects intestinal mucosa; and in the immune system, it reduces the activity of lymphocytes. With the exception of the blood vessels, dopamine in each of these peripheral systems is synthesized locally and exerts its effects near the cells that release it. Several important diseases of the nervous system are associated with dysfunctions of the dopamine system, and some of the key medications used to treat them work by altering the effects of dopamine. Parkinson's disease, a degenerative condition causing tremor and motor impairment, is caused by a loss of dopamine-secreting neurons in an area of the midbrain called the substantia nigra. Its metabolic precursor L-DOPA can be manufactured; Levodopa, a pure form of L-DOPA, is the most widely used treatment for Parkinson's. There is evidence that schizophrenia involves altered levels of dopamine activity, and most antipsychotic drugs used to treat this are dopamine antagonists which reduce dopamine activity.[10] Similar dopamine antagonist drugs are also some of the most effective anti-nausea agents. Restless legs syndrome and attention deficit hyperactivity disorder (ADHD) are associated with decreased dopamine activity.[11] Dopaminergic stimulants can be addictive in high doses, but some are used at lower doses to treat ADHD. Dopamine itself is available as a manufactured medication for intravenous injection. It is useful in the treatment of severe heart failure or cardiogenic shock.[12] In newborn babies it may be used for hypotension and septic shock.[13] Dopamine is synthesized in a restricted set of cell types, mainly neurons and cells in the medulla of the adrenal glands.[22] The primary and minor metabolic pathways respectively are: Primary: L-Phenylalanine → L-Tyrosine → L-DOPA → Dopamine[19][20] Minor: L-Phenylalanine → L-Tyrosine → p-Tyramine → Dopamine[19][20][21] Minor: L-Phenylalanine → m-Tyrosine → m-Tyramine → Dopamine[21][23][24] The direct precursor of dopamine, L-DOPA, can be synthesized indirectly from the essential amino acid phenylalanine or directly from the non-essential amino acid tyrosine.[25] These amino acids are found in nearly every protein and so are readily available in food, with tyrosine being the most common. Although dopamine is also found in many types of food, it is incapable of crossing the blood–brain barrier that surrounds and protects the brain.[26] It must therefore be synthesized inside the brain to perform its neuronal activity.[26] L-Phenylalanine is converted into L-tyrosine by the enzyme phenylalanine hydroxylase, with molecular oxygen (O2) and tetrahydrobiopterin as cofactors. L-Tyrosine is converted into L-DOPA by the enzyme tyrosine hydroxylase, with tetrahydrobiopterin, O2, and iron (Fe2+) as cofactors.[25] L-DOPA is converted into dopamine by the enzyme aromatic L-amino acid decarboxylase (also known as DOPA decarboxylase), with pyridoxal phosphate as the cofactor.[25] Dopamine itself is used as precursor in the synthesis of the neurotransmitters norepinephrine and epinephrine.[25] Dopamine is converted into norepinephrine by the enzyme dopamine β-hydroxylase, with O2 and L-ascorbic acid as cofactors.[25] Norepinephrine is converted into epinephrine by the enzyme phenylethanolamine N-methyltransferase with S-adenosyl-L-methionine as the cofactor.[25] Some of the cofactors also require their own synthesis.[25] Deficiency in any required amino acid or cofactor can impair the synthesis of dopamine, norepinephrine, and epinephrine.[25] Degradation Dopamine is broken down into inactive metabolites by a set of enzymes—monoamine oxidase (MAO), catechol-O-methyl transferase (COMT), and aldehyde dehydrogenase (ALDH), acting in sequence.[27] Both isoforms of monoamine oxidase, MAO-A and MAO-B, effectively metabolize dopamine.[25] Different breakdown pathways exist but the main end-product is homovanillic acid (HVA), which has no known biological activity.[27] From the bloodstream, homovanillic acid is filtered out by the kidneys and then excreted in the urine.[27] The two primary metabolic routes that convert dopamine into HVA are:[28] Dopamine → DOPAL → DOPAC → HVA – catalyzed by MAO, ALDH, and COMT respectively Dopamine → 3-Methoxytyramine → HVA – catalyzed by COMT and MAO+ALDH respectively In clinical research on schizophrenia, measurements of homovanillic acid in plasma have been used to estimate levels of dopamine activity in the brain. A difficulty in this approach however, is separating the high level of plasma homovanillic acid contributed by the metabolism of norepinephrine.[29][30] Although dopamine is normally broken down by an oxidoreductase enzyme, it is also susceptible to oxidation by direct reaction with oxygen, yielding quinones plus various free radicals as products.[31] The rate of oxidation can be increased by the presence of ferric iron or other factors. Quinones and free radicals produced by autoxidation of dopamine can poison cells, and there is evidence that this mechanism may contribute to the cell loss that occurs in Parkinson's disease and other conditions.[32]

   

Homocysteine

(2S)-2-amino-4-sulfanylbutanoic acid

C4H9NO2S (135.0353974)


A high level of blood serum homocysteine is a powerful risk factor for cardiovascular disease. Unfortunately, one study which attempted to decrease the risk by lowering homocysteine was not fruitful. This study was conducted on nearly 5000 Norwegian heart attack survivors who already had severe, late-stage heart disease. No study has yet been conducted in a preventive capacity on subjects who are in a relatively good state of health.; Elevated levels of homocysteine have been linked to increased fractures in elderly persons. The high level of homocysteine will auto-oxidize and react with reactive oxygen intermediates and damage endothelial cells and has a higher risk to form a thrombus. Homocysteine does not affect bone density. Instead, it appears that homocysteine affects collagen by interfering with the cross-linking between the collagen fibers and the tissues they reinforce. Whereas the HOPE-2 trial showed a reduction in stroke incidence, in those with stroke there is a high rate of hip fractures in the affected side. A trial with 2 homocysteine-lowering vitamins (folate and B12) in people with prior stroke, there was an 80\\\\\\% reduction in fractures, mainly hip, after 2 years. Interestingly, also here, bone density (and the number of falls) were identical in the vitamin and the placebo groups.; Homocysteine is a sulfur-containing amino acid that arises during methionine metabolism. Although its concentration in plasma is only about 10 micromolar (uM), even moderate hyperhomocysteinemia is associated with increased incidence of cardiovascular disease and Alzheimers disease. Elevations in plasma homocysteine are commonly found as a result of vitamin deficiencies, polymorphisms of enzymes of methionine metabolism, and renal disease. Pyridoxal, folic acid, riboflavin, and Vitamin B(12) are all required for methionine metabolism, and deficiency of each of these vitamins result in elevated plasma homocysteine. A polymorphism of methylenetetrahydrofolate reductase (C677T), which is quite common in most populations with a homozygosity rate of 10-15 \\\\\\%, is associated with moderate hyperhomocysteinemia, especially in the context of marginal folate intake. Plasma homocysteine is inversely related to plasma creatinine in patients with renal disease. This is due to an impairment in homocysteine removal in renal disease. The role of these factors, and of modifiable lifestyle factors, in affecting methionine metabolism and in determining plasma homocysteine levels is discussed. Homocysteine is an independent cardiovascular disease (CVD) risk factor modifiable by nutrition and possibly exercise. Homocysteine was first identified as an important biological compound in 1932 and linked with human disease in 1962 when elevated urinary homocysteine levels were found in children with mental retardation. This condition, called homocysteinuria, was later associated with premature occlusive CVD, even in children. These observations led to research investigating the relationship of elevated homocysteine levels and CVD in a wide variety of populations including middle age and elderly men and women with and without traditional risk factors for CVD. (PMID 17136938, 15630149); Homocysteine is an amino acid with the formula HSCH2CH2CH(NH2)CO2H. It is a homologue of the amino acid cysteine, differing by an additional methylene (-CH2-) group. It is biosynthesized from methionine by the removal of its terminal C? methyl group. Homocysteine can be recycled into methionine or converted into cysteine with the aid of B-vitamins.; Studies reported in 2006 have shown that giving vitamins [folic acid, B6 and B12] to reduce homocysteine levels may not quickly offer benefit, however a significant 25\\\\\\% reduction in stroke was found in the HOPE-2 study even in patients mostly with existing serious arterial decline although the overall death rate was not significantly changed by the intervention in the trial. Clearly, reducing homocysteine does not quickly repair existing... Homocysteine (CAS: 454-29-5) is a sulfur-containing amino acid that arises during methionine metabolism. Although its concentration in plasma is only about 10 micromolar (uM), even moderate hyperhomocysteinemia is associated with an increased incidence of cardiovascular disease and Alzheimers disease. Elevations in plasma homocysteine are commonly found as a result of vitamin deficiencies, polymorphisms of enzymes of methionine metabolism, and renal disease. It has been identified as a uremic toxin according to the European Uremic Toxin Working Group (PMID: 22626821). Pyridoxal, folic acid, riboflavin, and vitamin B(12) are all required for methionine metabolism, and deficiency of each of these vitamins result in elevated plasma homocysteine. A polymorphism of methylenetetrahydrofolate reductase (C677T), which is quite common in most populations with a homozygosity rate of 10-15 \\\\\\%, is associated with moderate hyperhomocysteinemia, especially in the context of marginal folate intake. Plasma homocysteine is inversely related to plasma creatinine in patients with renal disease. This is due to an impairment in homocysteine removal in renal disease. The role of these factors, and of modifiable lifestyle factors, in affecting methionine metabolism and in determining plasma homocysteine levels is discussed. Homocysteine is an independent cardiovascular disease (CVD) risk factor modifiable by nutrition and possibly exercise. Homocysteine was first identified as an important biological compound in 1932 and linked with human disease in 1962 when elevated urinary homocysteine levels were found in children with mental retardation. This condition, called homocystinuria, was later associated with premature occlusive CVD, even in children. These observations led to research investigating the relationship of elevated homocysteine levels and CVD in a wide variety of populations including middle age and elderly men and women with and without traditional risk factors for CVD (PMID: 17136938 , 15630149). Moreover, homocysteine is found to be associated with cystathionine beta-synthase deficiency, cystathioninuria, methylenetetrahydrofolate reductase deficiency, and sulfite oxidase deficiency, which are inborn errors of metabolism. [Spectral] L-Homocysteine (exact mass = 135.0354) and L-Valine (exact mass = 117.07898) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Homocysteine is biosynthesized naturally via a multi-step process.[9] First, methionine receives an adenosine group from ATP, a reaction catalyzed by S-adenosyl-methionine synthetase, to give S-adenosyl methionine (SAM-e). SAM-e then transfers the methyl group to an acceptor molecule, (e.g., norepinephrine as an acceptor during epinephrine synthesis, DNA methyltransferase as an intermediate acceptor in the process of DNA methylation). The adenosine is then hydrolyzed to yield L-homocysteine. L-Homocysteine has two primary fates: conversion via tetrahydrofolate (THF) back into L-methionine or conversion to L-cysteine.[10] Biosynthesis of cysteine Mammals biosynthesize the amino acid cysteine via homocysteine. Cystathionine β-synthase catalyses the condensation of homocysteine and serine to give cystathionine. This reaction uses pyridoxine (vitamin B6) as a cofactor. Cystathionine γ-lyase then converts this double amino acid to cysteine, ammonia, and α-ketobutyrate. Bacteria and plants rely on a different pathway to produce cysteine, relying on O-acetylserine.[11] Methionine salvage Homocysteine can be recycled into methionine. This process uses N5-methyl tetrahydrofolate as the methyl donor and cobalamin (vitamin B12)-related enzymes. More detail on these enzymes can be found in the article for methionine synthase. Other reactions of biochemical significance Homocysteine can cyclize to give homocysteine thiolactone, a five-membered heterocycle. Because of this "self-looping" reaction, homocysteine-containing peptides tend to cleave themselves by reactions generating oxidative stress.[12] Homocysteine also acts as an allosteric antagonist at Dopamine D2 receptors.[13] It has been proposed that both homocysteine and its thiolactone may have played a significant role in the appearance of life on the early Earth.[14] L-Homocysteine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=454-28-4 (retrieved 2024-06-29) (CAS RN: 6027-13-0). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). DL-Homocysteine is a weak neurotoxin, and can affect the production of kynurenic acid in the brain. DL-Homocysteine is a weak neurotoxin, and can affect the production of kynurenic acid in the brain. L-Homocysteine, a homocysteine metabolite, is a homocysteine that has L configuration. L-Homocysteine induces upregulation of cathepsin V that mediates vascular endothelial inflammation in hyperhomocysteinaemia[1][2].

   

S-adenosylhomocysteine (SAH)

(2S)-2-Amino-4-({[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl}sulphanyl)butanoic acid

C14H20N6O5S (384.12158300000004)


S-Adenosyl-L-homocysteine (SAH) is formed by the demethylation of S-adenosyl-L-methionine. S-Adenosylhomocysteine (AdoHcy or SAH) is also the immediate precursor of all of the homocysteine produced in the body. The reaction is catalyzed by S-adenosylhomocysteine hydrolase and is reversible with the equilibrium favoring formation of SAH. In vivo, the reaction is driven in the direction of homocysteine formation by the action of the enzyme adenosine deaminase which converts the second product of the S-adenosylhomocysteine hydrolase reaction, adenosine, to inosine. Except for methyl transfer from betaine and from methylcobalamin in the methionine synthase reaction, SAH is the product of all methylation reactions that involve S-adenosylmethionine (SAM) as the methyl donor. Methylation is significant in epigenetic regulation of protein expression via DNA and histone methylation. The inhibition of these SAM-mediated processes by SAH is a proven mechanism for metabolic alteration. Because the conversion of SAH to homocysteine is reversible, with the equilibrium favoring the formation of SAH, increases in plasma homocysteine are accompanied by an elevation of SAH in most cases. Disturbances in the transmethylation pathway indicated by abnormal SAH, SAM, or their ratio have been reported in many neurodegenerative diseases, such as dementia, depression, and Parkinsons disease (PMID:18065573, 17892439). Therefore, when present in sufficiently high levels, S-adenosylhomocysteine can act as an immunotoxin and a metabotoxin. An immunotoxin disrupts, limits the function, or destroys immune cells. A metabotoxin is an endogenous metabolite that causes adverse health effects at chronically high levels. Chronically high levels of S-adenosylhomocysteine are associated with S-adenosylhomocysteine (SAH) hydrolase deficiency and adenosine deaminase deficiency. S-Adenosylhomocysteine forms when there are elevated levels of homocysteine and adenosine. S-Adenosyl-L-homocysteine is a potent inhibitor of S-adenosyl-L-methionine-dependent methylation reactions. It is toxic to immature lymphocytes and can lead to immunosuppression (PMID:221926). S-adenosylhomocysteine, also known as adohcy or sah, is a member of the class of compounds known as 5-deoxy-5-thionucleosides. 5-deoxy-5-thionucleosides are 5-deoxyribonucleosides in which the ribose is thio-substituted at the 5position by a S-alkyl group. S-adenosylhomocysteine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). S-adenosylhomocysteine can be found in a number of food items such as rapini, european plum, rambutan, and pepper (c. pubescens), which makes S-adenosylhomocysteine a potential biomarker for the consumption of these food products. S-adenosylhomocysteine can be found primarily in blood, cerebrospinal fluid (CSF), feces, and urine, as well as throughout most human tissues. S-adenosylhomocysteine exists in all living species, ranging from bacteria to humans. In humans, S-adenosylhomocysteine is involved in several metabolic pathways, some of which include phosphatidylcholine biosynthesis PC(14:0/18:3(9Z,12Z,15Z)), phosphatidylcholine biosynthesis PC(22:4(7Z,10Z,13Z,16Z)/22:0), phosphatidylcholine biosynthesis PC(20:3(5Z,8Z,11Z)/22:2(13Z,16Z)), and phosphatidylcholine biosynthesis PC(18:3(6Z,9Z,12Z)/22:5(7Z,10Z,13Z,16Z,19Z)). S-adenosylhomocysteine is also involved in several metabolic disorders, some of which include 3-phosphoglycerate dehydrogenase deficiency, hawkinsinuria, non ketotic hyperglycinemia, and tyrosine hydroxylase deficiency. Moreover, S-adenosylhomocysteine is found to be associated with neurodegenerative disease and parkinsons disease. S-adenosylhomocysteine is a non-carcinogenic (not listed by IARC) potentially toxic compound. S-Adenosyl-L-homocysteine (SAH) is an amino acid derivative used in several metabolic pathways in most organisms. It is an intermediate in the synthesis of cysteine and adenosine . [Spectral] S-Adenosyl-L-homocysteine (exact mass = 384.12159) and Adenosine (exact mass = 267.09675) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] S-Adenosyl-L-homocysteine (exact mass = 384.12159) and Cytidine (exact mass = 243.08552) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from PDB, Protein Data Bank, WikiPathways Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS SAH (S-Adenosylhomocysteine) is an amino acid derivative and a modulartor in several metabolic pathways. It is an intermediate in the synthesis of cysteine and adenosine[1]. SAH is an inhibitor for METTL3-METTL14 heterodimer complex (METTL3-14) with an IC50 of 0.9 μM[2]. SAH (S-Adenosylhomocysteine) is an amino acid derivative and a modulartor in several metabolic pathways. It is an intermediate in the synthesis of cysteine and adenosine[1]. SAH is an inhibitor for METTL3-METTL14 heterodimer complex (METTL3-14) with an IC50 of 0.9 μM[2].

   

Bufotenin

3-(2-(Dimethylamino)ethyl)-1H-indol-5-ol (acd/name 4.0)

C12H16N2O (204.12625659999998)


A hallucinogenic serotonin analog found in frog or toad skins, mushrooms, higher plants, and mammals, especially in the brains, plasma, and urine of schizophrenics. Bufotenin has been used as a tool in CNS studies and misused as a psychedelic. Bufotenin (5-OH-DMT), is a tryptamine related to the neurotransmitter serotonin. It is an alkaloid found in the skin of some species of toads; in mushrooms, higher plants, and mammals. Bufotenin is a chemical constituent in the venom and eggs of several species of toads belonging to the Bufo genus, but most notably in the Colorado River toad (Bufo alvarius) as it is the only toad species in which bufotenin is present in large enough quantities for a psychoactive effect. Extracts of toad venom, containing bufotenin and other bioactive compounds, have been used in some traditional medicines (probably derived from Bufo gargarizans), which has been used medicinally for centuries in China. Bufotenin is a constituent of the seeds of Anadenanthera colubrina and Anadenanthera peregrina trees. Anadenanthera seeds have been used as an ingredient in psychedelic snuff preparations by indigenous cultures of the Caribbean, Central and South America. D018377 - Neurotransmitter Agents > D018490 - Serotonin Agents > D012702 - Serotonin Antagonists D002491 - Central Nervous System Agents > D011619 - Psychotropic Drugs > D006213 - Hallucinogens D009676 - Noxae > D011042 - Poisons > D014688 - Venoms

   

3-Methoxytyramine

4-(2-aminoethyl)-2-methoxyphenol

C9H13NO2 (167.0946238)


3-methoxytyramine, also known as 4-(2-amino-Ethyl)-2-methoxy-phenol or 3-O-Methyldopamine, is classified as a member of the Methoxyphenols. Methoxyphenols are compounds containing a methoxy group attached to the benzene ring of a phenol moiety. 3-methoxytyramine is considered to be slightly soluble (in water) and acidic. 3-methoxytyramine can be found primarily in human brain and most tissues tissues; and in blood, cerebrospinal fluid (csf) or urine. Within a cell, 3-methoxytyramine is primarily located in the cytoplasm The O-methylated derivative of dopamine. Dopamine is methylated by catechol-O-methyltransferase (COMT) to make 3-Methoxytyramine. This compound can be broken down to homovanillic acid by monoamine oxidase and aldehyde dehydrogenase. Elevated concentrations of this compound are indicated for a variety of brain and carcinoid tumors as well as certain mental disorders. [HMDB] COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS 3-Methoxytyramine, a well known extracellular metabolite of 3-hydroxytyramine/dopamine, is a neuromodulator.

   

1-Chloro-2,4-dinitrobenzene

1,3-Dinitro-4-chlorobenzene

C6H3ClN2O4 (201.9781348)


Dinitrochlorobenzene, also known as 4-chloro-1,3-dinitrobenzene or cdnb, is a member of the class of compounds known as nitrobenzenes. Nitrobenzenes are compounds containing a nitrobenzene moiety, which consists of a benzene ring with a carbon bearing a nitro group. Dinitrochlorobenzene is practically insoluble (in water) and an extremely weak acidic compound (based on its pKa). Dinitrochlorobenzene can be found in a number of food items such as black radish, american butterfish, hedge mustard, and other cereal product, which makes dinitrochlorobenzene a potential biomarker for the consumption of these food products. Dinitrochlorobenzene is produced commercially by the nitration of p-nitrochlorobenzene with a mixture of nitric and sulfuric acids. Other methods afford the compound less efficiently include the chlorination of dinitrobenzene, nitration of o-nitrochlorobenzene and the dinitration of chlorobenzene . D019995 - Laboratory Chemicals > D007202 - Indicators and Reagents C308 - Immunotherapeutic Agent > C2139 - Immunostimulant CONFIDENCE standard compound; INTERNAL_ID 41 D009676 - Noxae > D007509 - Irritants

   

Water

oxidane

H2O (18.0105642)


Water is a chemical substance that is essential to all known forms of life. It appears colorless to the naked eye in small quantities, though it is actually slightly blue in color. It covers 71\\% of Earths surface. Current estimates suggest that there are 1.4 billion cubic kilometers (330 million m3) of it available on Earth, and it exists in many forms. It appears mostly in the oceans (saltwater) and polar ice caps, but it is also present as clouds, rain water, rivers, freshwater aquifers, lakes, and sea ice. Water in these bodies perpetually moves through a cycle of evaporation, precipitation, and runoff to the sea. Clean water is essential to human life. In many parts of the world, it is in short supply. From a biological standpoint, water has many distinct properties that are critical for the proliferation of life that set it apart from other substances. It carries out this role by allowing organic compounds to react in ways that ultimately allow replication. All known forms of life depend on water. Water is vital both as a solvent in which many of the bodys solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism. In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) in order to grow larger molecules (e.g. starches, triglycerides and proteins for storage of fuels and information). In catabolism, water is used to break bonds in order to generate smaller molecules (e.g. glucose, fatty acids and amino acids to be used for fuels for energy use or other purposes). Water is thus essential and central to these metabolic processes. Water is also central to photosynthesis and respiration. Photosynthetic cells use the suns energy to split off waters hydrogen from oxygen. Hydrogen is combined with CO2 (absorbed from air or water) to form glucose and release oxygen. All living cells use such fuels and oxidize the hydrogen and carbon to capture the suns energy and reform water and CO2 in the process (cellular respiration). Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H+, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as hydroxide ion (OH-) to form water. Water is considered to be neutral, with a pH (the negative log of the hydrogen ion concentration) of 7. Acids have pH values less than 7 while bases have values greater than 7. Stomach acid (HCl) is useful to digestion. However, its corrosive effect on the esophagus during reflux can temporarily be neutralized by ingestion of a base such as aluminum hydroxide to produce the neutral molecules water and the salt aluminum chloride. Human biochemistry that involves enzymes usually performs optimally around a biologically neutral pH of 7.4. (Wikipedia). Water, also known as purified water or dihydrogen oxide, is a member of the class of compounds known as homogeneous other non-metal compounds. Homogeneous other non-metal compounds are inorganic non-metallic compounds in which the largest atom belongs to the class of other nonmetals. Water can be found in a number of food items such as caraway, oxheart cabbage, alaska wild rhubarb, and japanese walnut, which makes water a potential biomarker for the consumption of these food products. Water can be found primarily in most biofluids, including ascites Fluid, blood, cerebrospinal fluid (CSF), and lymph, as well as throughout all human tissues. Water exists in all living species, ranging from bacteria to humans. In humans, water is involved in several metabolic pathways, some of which include cardiolipin biosynthesis CL(20:4(5Z,8Z,11Z,14Z)/18:0/20:4(5Z,8Z,11Z,14Z)/18:2(9Z,12Z)), cardiolipin biosynthesis cl(i-13:0/i-15:0/i-20:0/i-24:0), cardiolipin biosynthesis CL(18:0/18:0/20:4(5Z,8Z,11Z,14Z)/22:5(7Z,10Z,13Z,16Z,19Z)), and cardiolipin biosynthesis cl(a-13:0/i-18:0/i-13:0/i-19:0). Water is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis tg(i-21:0/i-13:0/21:0), de novo triacylglycerol biosynthesis tg(22:0/20:0/i-20:0), de novo triacylglycerol biosynthesis tg(a-21:0/i-20:0/i-14:0), and de novo triacylglycerol biosynthesis tg(i-21:0/a-17:0/i-12:0). Water is a drug which is used for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection, according to instructions of the manufacturer of the drug to be administered [fda label]. Water plays an important role in the world economy. Approximately 70\\% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of long-distance trade of commodities (such as oil and natural gas) and manufactured products is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving .

   

Oxygen

Molecular oxygen

O2 (31.98983)


Oxygen is the third most abundant element in the universe after hydrogen and helium and the most abundant element by mass in the Earths crust. Diatomic oxygen gas constitutes 20.9\\% of the volume of air. All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all living organisms. Green algae and cyanobacteria in marine environments provide about 70\\% of the free oxygen produced on earth and the rest is produced by terrestrial plants. Oxygen is used in mitochondria to help generate adenosine triphosphate (ATP) during oxidative phosphorylation. For animals, a constant supply of oxygen is indispensable for cardiac viability and function. To meet this demand, an adult human, at rest, inhales 1.8 to 2.4 grams of oxygen per minute. This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. At a resting pulse rate, the heart consumes approximately 8-15 ml O2/min/100 g tissue. This is significantly more than that consumed by the brain (approximately 3 ml O2/min/100 g tissue) and can increase to more than 70 ml O2/min/100 g myocardial tissue during vigorous exercise. As a general rule, mammalian heart muscle cannot produce enough energy under anaerobic conditions to maintain essential cellular processes; thus, a constant supply of oxygen is indispensable to sustain cardiac function and viability. However, the role of oxygen and oxygen-associated processes in living systems is complex, and they and can be either beneficial or contribute to cardiac dysfunction and death (through reactive oxygen species). Reactive oxygen species (ROS) are a family of oxygen-derived free radicals that are produced in mammalian cells under normal and pathologic conditions. Many ROS, such as the superoxide anion (O2-)and hydrogen peroxide (H2O2), act within blood vessels, altering mechanisms mediating mechanical signal transduction and autoregulation of cerebral blood flow. Reactive oxygen species are believed to be involved in cellular signaling in blood vessels in both normal and pathologic states. The major pathway for the production of ROS is by way of the one-electron reduction of molecular oxygen to form an oxygen radical, the superoxide anion (O2-). Within the vasculature there are several enzymatic sources of O2-, including xanthine oxidase, the mitochondrial electron transport chain, and nitric oxide (NO) synthases. Studies in recent years, however, suggest that the major contributor to O2- levels in vascular cells is the membrane-bound enzyme NADPH-oxidase. Produced O2- can react with other radicals, such as NO, or spontaneously dismutate to produce hydrogen peroxide (H2O2). In cells, the latter reaction is an important pathway for normal O2- breakdown and is usually catalyzed by the enzyme superoxide dismutase (SOD). Once formed, H2O2 can undergo various reactions, both enzymatic and nonenzymatic. The antioxidant enzymes catalase and glutathione peroxidase act to limit ROS accumulation within cells by breaking down H2O2 to H2O. Metabolism of H2O2 can also produce other, more damaging ROS. For example, the endogenous enzyme myeloperoxidase uses H2O2 as a substrate to form the highly reactive compound hypochlorous acid. Alternatively, H2O2 can undergo Fenton or Haber-Weiss chemistry, reacting with Fe2+/Fe3+ ions to form toxic hydroxyl radicals (-.OH). (PMID: 17027622, 15765131) [HMDB]. Oxygen is found in many foods, some of which are soy bean, watermelon, sweet basil, and spinach. Oxygen is the third most abundant element in the universe after hydrogen and helium and the most abundant element by mass in the Earths crust. Diatomic oxygen gas constitutes 20.9\\% of the volume of air. All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all living organisms. Green algae and cyanobacteria in marine environments provide about 70\\% of the free oxygen produced on earth and the rest is produced by terrestrial plants. Oxygen is used in mitochondria to help generate adenosine triphosphate (ATP) during oxidative phosphorylation. For animals, a constant supply of oxygen is indispensable for cardiac viability and function. To meet this demand, an adult human, at rest, inhales 1.8 to 2.4 grams of oxygen per minute. This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. At a resting pulse rate, the heart consumes approximately 8-15 ml O2/min/100 g tissue. This is significantly more than that consumed by the brain (approximately 3 ml O2/min/100 g tissue) and can increase to more than 70 ml O2/min/100 g myocardial tissue during vigorous exercise. As a general rule, mammalian heart muscle cannot produce enough energy under anaerobic conditions to maintain essential cellular processes; thus, a constant supply of oxygen is indispensable to sustain cardiac function and viability. However, the role of oxygen and oxygen-associated processes in living systems is complex, and they and can be either beneficial or contribute to cardiac dysfunction and death (through reactive oxygen species). Reactive oxygen species (ROS) are a family of oxygen-derived free radicals that are produced in mammalian cells under normal and pathologic conditions. Many ROS, such as the superoxide anion (O2-)and hydrogen peroxide (H2O2), act within blood vessels, altering mechanisms mediating mechanical signal transduction and autoregulation of cerebral blood flow. Reactive oxygen species are believed to be involved in cellular signaling in blood vessels in both normal and pathologic states. The major pathway for the production of ROS is by way of the one-electron reduction of molecular oxygen to form an oxygen radical, the superoxide anion (O2-). Within the vasculature there are several enzymatic sources of O2-, including xanthine oxidase, the mitochondrial electron transport chain, and nitric oxide (NO) synthases. Studies in recent years, however, suggest that the major contributor to O2- levels in vascular cells is the membrane-bound enzyme NADPH-oxidase. Produced O2- can react with other radicals, such as NO, or spontaneously dismutate to produce hydrogen peroxide (H2O2). In cells, the latter reaction is an important pathway for normal O2- breakdown and is usually catalyzed by the enzyme superoxide dismutase (SOD). Once formed, H2O2 can undergo various reactions, both enzymatic and nonenzymatic. The antioxidant enzymes catalase and glutathione peroxidase act to limit ROS accumulation within cells by breaking down H2O2 to H2O. Metabolism of H2O2 can also produce other, more damaging ROS. For example, the endogenous enzyme myeloperoxidase uses H2O2 as a substrate to form the highly reactive compound hypochlorous acid. Alternatively, H2O2 can undergo Fenton or Haber-Weiss chemistry, reacting with Fe2+/Fe3+ ions to form toxic hydroxyl radicals (-.OH). (PMID: 17027622, 15765131). V - Various > V03 - All other therapeutic products > V03A - All other therapeutic products > V03AN - Medical gases

   

ammonia

N-acetyl-α-D-glucosamine 1-phosphate

H3N (17.0265478)


An azane that consists of a single nitrogen atom covelently bonded to three hydrogen atoms. Ammonia, also known as nh3 or ammonia solution, is a member of the class of compounds known as homogeneous other non-metal compounds. Homogeneous other non-metal compounds are inorganic non-metallic compounds in which the largest atom belongs to the class of other nonmetals. Ammonia can be found in a number of food items such as rose hip, yardlong bean, cereals and cereal products, and ceylon cinnamon, which makes ammonia a potential biomarker for the consumption of these food products. Ammonia can be found primarily in blood, cellular cytoplasm, cerebrospinal fluid (CSF), and urine, as well as throughout all human tissues. Ammonia exists in all eukaryotes, ranging from yeast to humans. In humans, ammonia is involved in several metabolic pathways, some of which include glucose-alanine cycle, phenylalanine and tyrosine metabolism, homocysteine degradation, and d-arginine and d-ornithine metabolism. Ammonia is also involved in several metabolic disorders, some of which include ureidopropionase deficiency, hyperornithinemia-hyperammonemia-homocitrullinuria [hhh-syndrome], non ketotic hyperglycinemia, and beta-mercaptolactate-cysteine disulfiduria. Moreover, ammonia is found to be associated with 3-Hydroxy-3-methylglutaryl-CoA lyase deficiency, 3-Methyl-crotonyl-glycinuria, citrullinemia type I, and short bowel syndrome. Ammonia is a non-carcinogenic (not listed by IARC) potentially toxic compound. Ammonia or azane is a compound of nitrogen and hydrogen with the formula NH3. The simplest pnictogen hydride, ammonia is a colourless gas with a characteristic pungent smell. It is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products . Acute Exposure: EYES: irrigate opened eyes for several minutes under running water. INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice. SKIN: should be treated immediately by rinsing the affected parts in cold running water for at least 15 minutes, followed by thorough washing with soap and water. If necessary, the person should shower and change contaminated clothing and shoes, and then must seek medical attention. INHALATION: supply fresh air. If required provide artificial respiration. (z)-n-coumaroyl-5-hydroxyanthranilic acid is a member of the class of compounds known as avenanthramides. Avenanthramides are a group of phenolic alkaloids consisting of conjugate of three phenylpropanoids (ferulic, caffeic, or p-coumaric acid) and anthranilic acid (z)-n-coumaroyl-5-hydroxyanthranilic acid is practically insoluble (in water) and a weakly acidic compound (based on its pKa). (z)-n-coumaroyl-5-hydroxyanthranilic acid can be found in cereals and cereal products and oat, which makes (z)-n-coumaroyl-5-hydroxyanthranilic acid a potential biomarker for the consumption of these food products.

   

Hydrogen peroxide

Hydrogen peroxide (H2O2)

H2O2 (34.0054792)


Hydrogen peroxide (H2O2) is a very pale blue liquid that appears colourless in a dilute solution. H2O2 is slightly more viscous than water and is a weak acid. H2O2 is unstable and slowly decomposes in the presence of light. It has strong oxidizing properties and is, therefore, a powerful bleaching agent that is mostly used for bleaching paper. H2O2 has also found use as a disinfectant and as an oxidizer. H2O2 in the form of carbamide peroxide is widely used for tooth whitening (bleaching), both in professionally- and in self-administered products. H2O2 is a well-documented component of living cells and is a normal metabolite of oxygen in the aerobic metabolism of cells and tissues. A total of 31 human cellular H2O2 generating enzymes has been identified so far (PMID: 25843657). H2O2 plays important roles in host defence and oxidative biosynthetic reactions. At high levels (>100 nM) H2O2 is toxic to most cells due to its ability to non-specifically oxidize proteins, membranes and DNA, leading to general cellular damage and dysfunction. However, at low levels (<10 nM), H2O2 functions as a signalling agent, particularly in higher organisms. In plants, H2O2 plays a role in signalling to cause cell shape changes such as stomatal closure and root growth. As a messenger molecule in vertebrates, H2O2 diffuses through cells and tissues to initiate cell shape changes, to drive vascular remodelling, and to activate cell proliferation and recruitment of immune cells. H2O2 also plays a role in redox sensing, signalling, and redox regulation (PMID: 28110218). This is normally done through molecular redox “switches” such as thiol-containing proteins. The production and decomposition of H2O2 are tightly regulated (PMID: 17434122). In humans, H2O2 can be generated in response to various stimuli, including cytokines and growth factors. H2O2 is degraded by several enzymes including catalase and superoxide dismutase (SOD), both of which play important roles in keeping the amount of H2O2 in the body below toxic levels. H2O2 also appears to play a role in vitiligo. Vitiligo is a skin pigment disorder leading to patchy skin colour, especially among dark-skinned individuals. Patients with vitiligo have low catalase levels in their skin, leading to higher levels of H2O2. High levels of H2O2 damage the epidermal melanocytes, leading to a loss of pigment (PMID: 10393521). Accumulating evidence suggests that hydrogen peroxide H2O2 plays an important role in cancer development. Experimental data have shown that cancer cells produce high amounts of H2O2. An increase in the cellular levels of H2O2 has been linked to several key alterations in cancer, including DNA changes, cell proliferation, apoptosis resistance, metastasis, angiogenesis and hypoxia-inducible factor 1 (HIF-1) activation (PMID: 17150302, 17335854, 16677071, 16607324, 16514169). H2O2 is found in most cells, tissues, and biofluids. H2O2 levels in the urine can be significantly increased with the consumption of coffee and other polyphenolic-containing beverages (wine, tea) (PMID: 12419961). In particular, roasted coffee has high levels of 1,2,4-benzenetriol which can, on its own, lead to the production of H2O2. Normal levels of urinary H2O2 in non-coffee drinkers or fasted subjects are between 0.5-3 uM/mM creatinine whereas, for those who drink coffee, the levels are between 3-10 uM/mM creatinine (PMID: 12419961). It is thought that H2O2 in urine could act as an antibacterial agent and that H2O2 is involved in the regulation of glomerular function (PMID: 10766414). A - Alimentary tract and metabolism > A01 - Stomatological preparations > A01A - Stomatological preparations > A01AB - Antiinfectives and antiseptics for local oral treatment D - Dermatologicals > D08 - Antiseptics and disinfectants > D08A - Antiseptics and disinfectants S - Sensory organs > S02 - Otologicals > S02A - Antiinfectives > S02AA - Antiinfectives It is used in foods as a bleaching agent, antimicrobial agent and oxidising agent C254 - Anti-Infective Agent > C28394 - Topical Anti-Infective Agent D009676 - Noxae > D016877 - Oxidants > D010545 - Peroxides D000890 - Anti-Infective Agents

   

S-Adenosylmethionine

[(3S)-3-amino-3-carboxypropyl]({[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl})methylsulfanium

C15H23N6O5S+ (399.1450568)


S-adenosylmethionine, also known as sam or adomet, is a member of the class of compounds known as 5-deoxy-5-thionucleosides. 5-deoxy-5-thionucleosides are 5-deoxyribonucleosides in which the ribose is thio-substituted at the 5position by a S-alkyl group. S-adenosylmethionine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). S-adenosylmethionine can be found in a number of food items such as common grape, half-highbush blueberry, jerusalem artichoke, and thistle, which makes S-adenosylmethionine a potential biomarker for the consumption of these food products. S-adenosylmethionine can be found primarily in blood, cerebrospinal fluid (CSF), feces, and urine, as well as throughout most human tissues. S-adenosylmethionine exists in all eukaryotes, ranging from yeast to humans. In humans, S-adenosylmethionine is involved in several metabolic pathways, some of which include phosphatidylcholine biosynthesis PC(22:1(13Z)/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), phosphatidylcholine biosynthesis PC(22:0/18:3(9Z,12Z,15Z)), phosphatidylcholine biosynthesis PC(24:0/24:0), and phosphatidylcholine biosynthesis PC(20:5(5Z,8Z,11Z,14Z,17Z)/20:0). S-adenosylmethionine is also involved in several metabolic disorders, some of which include methylenetetrahydrofolate reductase deficiency (MTHFRD), 3-phosphoglycerate dehydrogenase deficiency, monoamine oxidase-a deficiency (MAO-A), and aromatic l-aminoacid decarboxylase deficiency. Moreover, S-adenosylmethionine is found to be associated with diabetes mellitus type 2 and neurodegenerative disease. S-adenosylmethionine is a non-carcinogenic (not listed by IARC) potentially toxic compound. S-Adenosyl methionine is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throughout the body, most SAM-e is produced and consumed in the liver. More than 40 methyl transfers from SAM-e are known, to various substrates such as nucleic acids, proteins, lipids and secondary metabolites. It is made from adenosine triphosphate (ATP) and methionine by methionine adenosyltransferase (EC 2.5.1.6). SAM was first discovered by Giulio Cantoni in 1952 . Significant first-pass metabolism in the liver. Approximately 50\\\% of S-Adenosylmethionine (SAMe) is metabolized in the liver. SAMe is metabolized to S-adenosylhomocysteine, which is then metabolized to homocysteine. Homocysteine can either be metabolized to cystathionine and then cysteine or to methionine. The cofactor in the metabolism of homocysteine to cysteine is vitamin B6. Cofactors for the metabolism of homocysteine to methionine are folic acid, vitamin B12 and betaine (T3DB). S-Adenosylmethionine (CAS: 29908-03-0), also known as SAM or AdoMet, is a physiologic methyl radical donor involved in enzymatic transmethylation reactions and present in all living organisms. It possesses anti-inflammatory activity and has been used in the treatment of chronic liver disease (From Merck, 11th ed). S-Adenosylmethionine is a natural substance present in the cells of the body. It plays a crucial biochemical role by donating a one-carbon methyl group in a process called transmethylation. S-Adenosylmethionine, formed from the reaction of L-methionine and adenosine triphosphate catalyzed by the enzyme S-adenosylmethionine synthetase, is the methyl-group donor in the biosynthesis of both DNA and RNA nucleic acids, phospholipids, proteins, epinephrine, melatonin, creatine, and other molecules.