Reaction Process: Reactome:R-TGU-211958
Miscellaneous substrates related metabolites
find 15 related metabolites which is associated with chemical reaction(pathway) Miscellaneous substrates
H+ + Oxygen + TES + TPNH ⟶ 6BHT + H2O + TPN
Testosterone
Testosterone is the primary male sex hormone and anabolic steroid from the androstane class of steroids. It is the most important androgen in potency and quantity for vertebrates. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. In addition, testosterone is involved in health and well-being, and the prevention of osteoporosis. Testosterone exerts its action through binding to and activation of the androgen receptor. In mammals, testosterone is metabolized mainly in the liver. Approximately 50\\% of testosterone is metabolized via conjugation into testosterone glucuronide and to a lesser extent testosterone sulfate by glucuronosyltransferases and sulfotransferases. An additional 40\\% of testosterone is metabolized in equal proportions into the 17-ketosteroids androsterone and etiocholanolone via the combined actions of 5alpha- and 5beta-reductases, 3alpha-hydroxysteroid dehydrogenase, and 17beta-HSD. Like other steroid hormones, testosterone is derived from cholesterol. The first step in the biosynthesis of testosterone involves the oxidative cleavage of the side-chain of cholesterol by the cholesterol side-chain cleavage enzyme (P450scc, CYP11A1) to give pregnenolone. In the next step, two additional carbon atoms are removed by the CYP17A1 (17alpha-hydroxylase/17,20-lyase) enzyme to yield a variety of C19 steroids. In addition, the 3beta-hydroxyl group is oxidized by 3beta-hydroxysteroid dehydrogenase to produce androstenedione. In the final and rate limiting step, the C17 keto group androstenedione is reduced by 17beta-hydroxysteroid hydrogenase to yield testosterone. Testosterone is synthesized and released by the Leydig cells in the testes that lie between the tubules and comprise less than 5\\% of the total testicular volume. Testosterone diffuses into the seminiferous tubules where it is essential for maintaining spermatogenesis. Some testosterone binds to an androgen-binding protein (ABP) that is produced by the Sertoli cells and is homologous to the sex-hormone binding globulin that transports testosterone in the general circulation. The ABP carries testosterone in the testicular fluid where it maintains the activity of the accessory sex glands and may also help to retain testosterone within the tubule and bind excess free hormone. Some testosterone is converted to estradiol by Sertoli cell-derived aromatase enzyme. Leydig cell steroidogenesis is controlled primarily by luteinizing hormone with negative feedback of testosterone on the hypothalamic-pituitary axis. The requirement of spermatogenesis for high local concentrations of testosterone means that loss of androgen production is likely to be accompanied by loss of spermatogenesis. Indeed, if testicular androgen production is inhibited by the administration of exogenous androgens then spermatogenesis ceases. This is the basis of using exogenous testosterone as a male contraceptive. The largest amounts of testosterone (>95\\%) are produced by the testes in men, while the adrenal glands account for most of the remainder. Testosterone is also synthesized in far smaller total quantities in women by the adrenal glands, thecal cells of the ovaries, and, during pregnancy, by the placenta. Testosterone levels fall by about 1\\% each year in men. Therefore, with increasing longevity and the aging of the population, the number of older men with testosterone deficiency will increase substantially over the next several decades. Serum testosterone levels decrease progressively in aging men, but the rate and magnitude of decrease vary considerably. Approximately 1\\% of healthy young men have total serum testosterone levels below normal; in contrast, approximately 20\\% of healthy men over age 60 years have serum testosterone levels below normal. (PMID: 17904450, 17875487). G - Genito urinary system and sex hormones > G03 - Sex hormones and modulators of the genital system > G03B - Androgens > G03BA - 3-oxoandrosten (4) derivatives D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006728 - Hormones > D000728 - Androgens C147908 - Hormone Therapy Agent > C548 - Therapeutic Hormone > C1636 - Therapeutic Steroid Hormone C147908 - Hormone Therapy Agent > C548 - Therapeutic Hormone > C2360 - Anabolic Steroid
all-trans-Retinoic acid
all-trans-Retinoic acid is an isomer of retinoic acid, the oxidized form of vitamin A. Retinoic acid functions in determining position along embryonic anterior/posterior axis in chordates. It acts through Hox genes, which ultimately controls anterior/posterior patterning in early developmental stages (PMID:17495912). It is an important regulator of gene expression during growth and development, and in neoplasms. As a drug, all-trans-retinoic acid is known as tretinoin. Tretinoin is derived from maternal vitamin A and is essential for normal growth and embryonic development. An excess of tretinoin can be teratogenic. Tretinoin is used in the treatment of psoriasis, acne vulgaris, and several other skin diseases. It has also been approved for use in promyelocytic leukemia (leukemia, promyelocytic, acute). Retinoic acid is the oxidized form of Vitamin A. It functions in determining position along embryonic anterior/posterior axis in chordates. It acts through Hox genes, which ultimately controls anterior/posterior patterning in early developmental stages (PMID: 17495912). It is an important regulator of gene expression during growth and development, and in neoplasms. Tretinoin, also known as retinoic acid and derived from maternal vitamin A, is essential for normal growth and embryonic development. An excess of tretinoin can be teratogenic. It is used in the treatment of psoriasis; acne vulgaris; and several other skin diseases. It has also been approved for use in promyelocytic leukemia (leukemia, promyelocytic, acute). [HMDB] L - Antineoplastic and immunomodulating agents > L01 - Antineoplastic agents > L01X - Other antineoplastic agents > L01XF - Retinoids for cancer treatment D - Dermatologicals > D10 - Anti-acne preparations > D10A - Anti-acne preparations for topical use > D10AD - Retinoids for topical use in acne C274 - Antineoplastic Agent > C2122 - Cell Differentiating Agent > C1934 - Differentiation Inducer C274 - Antineoplastic Agent > C163758 - Targeted Therapy Agent > C804 - Retinoic Acid Agent Acquisition and generation of the data is financially supported in part by CREST/JST. C308 - Immunotherapeutic Agent > C129820 - Antineoplastic Immunomodulating Agent D020011 - Protective Agents > D000975 - Antioxidants > D002338 - Carotenoids D003879 - Dermatologic Agents > D007641 - Keratolytic Agents D000970 - Antineoplastic Agents Retinoic acid is a metabolite of vitamin A that plays important roles in cell growth, differentiation, and organogenesis. Retinoic acid is a natural agonist of RAR nuclear receptors, with IC50s of 14 nM for RARα/β/γ. Retinoic acid bind to PPARβ/δ with Kd of 17 nM. Retinoic acid acts as an inhibitor of transcription factor Nrf2 through activation of retinoic acid receptor alpha. Retinoic acid is a metabolite of vitamin A that plays important roles in cell growth, differentiation, and organogenesis. Retinoic acid is a natural agonist of RAR nuclear receptors, with IC50s of 14 nM for RARα/β/γ. Retinoic acid bind to PPARβ/δ with Kd of 17 nM. Retinoic acid acts as an inhibitor of transcription factor Nrf2 through activation of retinoic acid receptor alpha. Retinoic acid is a metabolite of vitamin A that plays important roles in cell growth, differentiation, and organogenesis. Retinoic acid is a natural agonist of RAR nuclear receptors, with IC50s of 14 nM for RARα/β/γ. Retinoic acid bind to PPARβ/δ with Kd of 17 nM. Retinoic acid acts as an inhibitor of transcription factor Nrf2 through activation of retinoic acid receptor alpha.
Nicotinamide adenine dinucleotide phosphate
NADPH is the reduced form of NADP+, and NADP+ is the oxidized form of NADPH. Nicotinamide adenine dinucleotide phosphate (NADP) is a coenzyme composed of ribosylnicotinamide 5-phosphate (NMN) coupled with a pyrophosphate linkage to 5-phosphate adenosine 2,5-bisphosphate. NADP serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). NADP is formed through the addition of a phosphate group to the 2 position of the adenosyl nucleotide through an ester linkage (Dorland, 27th ed). This extra phosphate is added by the enzyme NAD+ kinase and removed via NADP+ phosphatase. NADP is also known as TPN (triphosphopyridine nucleotide) and it is an important cofactor used in anabolic reactions in all forms of cellular life. Examples include the Calvin cycle, cholesterol synthesis, fatty acid elongation, and nucleic acid synthesis (Wikipedia). Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5-phosphate (NMN) coupled by pyrophosphate linkage to the 5-phosphate adenosine 2,5-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed.) [HMDB]. NADPH is found in many foods, some of which are american pokeweed, rice, ginseng, and ostrich fern. COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS
Arachidonic acid
Arachidonic acid is a polyunsaturated, essential fatty acid that has a 20-carbon chain as a backbone and four cis-double bonds at the C5, C8, C11, and C14 positions. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is synthesized from dietary linoleic acid. Arachidonic acid mediates inflammation and the functioning of several organs and systems either directly or upon its conversion into eicosanoids. Arachidonic acid in cell membrane phospholipids is the substrate for the synthesis of a range of biologically active compounds (eicosanoids) including prostaglandins, thromboxanes, and leukotrienes. These compounds can act as mediators in their own right and can also act as regulators of other processes, such as platelet aggregation, blood clotting, smooth muscle contraction, leukocyte chemotaxis, inflammatory cytokine production, and immune function. Arachidonic acid can be metabolized by cytochrome p450 (CYP450) enzymes into 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids (EETs), their corresponding dihydroxyeicosatrienoic acids (DHETs), and 20-hydroxyeicosatetraenoic acid (20-HETE). The production of kidney CYP450 arachidonic acid metabolites is altered in diabetes, pregnancy, hepatorenal syndrome, and in various models of hypertension, and it is likely that changes in this system contribute to the abnormalities in renal function that are associated with many of these conditions. Phospholipase A2 (PLA2) catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid (PMID: 12736897, 12736897, 12700820, 12570747, 12432908). The beneficial effects of omega-3 fatty acids are believed to be due in part to selective alteration of arachidonate metabolism that involves cyclooxygenase (COX) enzymes (PMID: 23371504). 9-Oxononanoic acid (9-ONA), one of the major products of peroxidized fatty acids, was found to stimulate the activity of phospholipase A2 (PLA2), the key enzyme to initiate the arachidonate cascade and eicosanoid production (PMID: 23704812). Arachidonate lipoxygenase (ALOX) enzymes metabolize arachidonic acid to generate potent inflammatory mediators and play an important role in inflammation-associated diseases (PMID: 23404351). Essential fatty acid. Constituent of many animal phospholipids Arachidonic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=506-32-1 (retrieved 2024-07-15) (CAS RN: 506-32-1). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Arachidonic acid is an essential fatty acid and a major constituent of biomembranes. Arachidonic acid is an essential fatty acid and a major constituent of biomembranes.
Indolin-2-one
1,3-Dihydro-(2H)-indol-2-one, also known as 2-oxindole or 2-indolinone, belongs to the class of organic compounds known as indolines. Indolines are compounds containing an indole moiety, which consists of pyrrolidine ring fused to benzene to form 2,3-dihydroindole. CONFIDENCE standard compound; INTERNAL_ID 2508 COVID info from PDB, Protein Data Bank Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS Oxindole (Indolin-2-one) is an aromatic heterocyclic building block. 2-indolinone derivatives have become lead compounds in the research of kinase inhibitors. Oxindole (Indolin-2-one) is an aromatic heterocyclic building block. 2-indolinone derivatives have become lead compounds in the research of kinase inhibitors.
Indole
Indole is an aromatic heterocyclic organic compound. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. The participation of the nitrogen lone electron pair in the aromatic ring means that indole is not a base, and it does not behave like a simple amine. Indole is a microbial metabolite and it can be produced by bacteria as a degradation product of the amino acid tryptophan. It occurs naturally in human feces and has an intense fecal smell. At very low concentrations, however, indole has a flowery smell and is a constituent of many flower scents (such as orange blossoms) and perfumes. As a volatile organic compound, indole has been identified as a fecal biomarker of Clostridium difficile infection (PMID: 30986230). Natural jasmine oil, used in the perfume industry, contains around 2.5\\\\\% of indole. Indole also occurs in coal tar. Indole has been found to be produced in a number of bacterial genera including Alcaligenes, Aspergillus, Escherichia, and Pseudomonas (PMID: 23194589, 2310183, 9680309). Indole plays a role in bacterial biofilm formation, bacterial motility, bacterial virulence, plasmid stability, and antibiotic resistance. It also functions as an intercellular signalling molecule (PMID: 26115989). Recently, it was determined that the bacterial membrane-bound histidine sensor kinase (HK) known as CpxA acts as a bacterial indole sensor to facilitate signalling (PMID: 31164470). It has been found that decreased indole concentrations in the gut promote bacterial pathogenesis, while increased levels of indole in the gut decrease bacterial virulence gene expression (PMID: 31164470). As a result, enteric pathogens sense a gradient of indole concentrations in the gut to migrate to different niches and successfully establish an infection. Constituent of several flower oils, especies of Jasminum and Citrus subspecies (Oleaceae) production of bacterial dec. of proteins. Flavouring ingredientand is also present in crispbread, Swiss cheese, Camembert cheese, wine, cocoa, black and green tea, rum, roasted filbert, rice bran, clary sage, raw shrimp and other foodstuffs Indole. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=120-72-9 (retrieved 2024-07-16) (CAS RN: 120-72-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Indole is an endogenous metabolite. Indole is an endogenous metabolite.
6beta-Hydroxytestosterone
Testosterone is reported to have an acute vasodilating action in vitro, an effect that may impart a favourable haemodynamic response in patients with chronic heart failure.
NADP+
[C21H29N7O17P3]+ (744.0832754)
[Spectral] NADP+ (exact mass = 743.07545) and NAD+ (exact mass = 663.10912) 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. COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS
Water
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
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
4-Hydroxyretinoic acid
4-Hydroxyretinoic acid is an NADPH-dependent hydroxylation metabolite of retinoic acid in the microsomes, via the cytochrome P-450 system. Retinoic acid is an activated metabolite of retinol that supports the systemic functions of vitamin A in vivo. (PMID: 1538719, 1932598, 2851384) [HMDB] 4-Hydroxyretinoic acid is an NADPH-dependent hydroxylation metabolite of retinoic acid in the microsomes, via the cytochrome P-450 system. Retinoic acid is an activated metabolite of retinol that supports the systemic functions of vitamin A in vivo. (PMID: 1538719, 1932598, 2851384). D020011 - Protective Agents > D000975 - Antioxidants > D002338 - Carotenoids
Hydrogen Ion
Hydrogen ion, also known as proton or h+, is a member of the class of compounds known as other non-metal hydrides. Other non-metal hydrides are inorganic compounds in which the heaviest atom bonded to a hydrogen atom is belongs to the class of other non-metals. Hydrogen ion can be found in a number of food items such as lowbush blueberry, groundcherry, parsley, and tarragon, which makes hydrogen ion a potential biomarker for the consumption of these food products. Hydrogen ion exists in all living organisms, ranging from bacteria to humans. In humans, hydrogen ion is involved in several metabolic pathways, some of which include cardiolipin biosynthesis cl(i-13:0/a-25:0/a-21:0/i-15:0), cardiolipin biosynthesis cl(a-13:0/a-17:0/i-13:0/a-25:0), cardiolipin biosynthesis cl(i-12:0/i-13:0/a-17:0/a-15:0), and cardiolipin biosynthesis CL(16:1(9Z)/22:5(4Z,7Z,10Z,13Z,16Z)/18:1(11Z)/22:5(7Z,10Z,13Z,16Z,19Z)). Hydrogen ion is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis TG(20:3(8Z,11Z,14Z)/22:6(4Z,7Z,10Z,13Z,16Z,19Z)/22:5(7Z,10Z,13Z,16Z,19Z)), de novo triacylglycerol biosynthesis TG(18:2(9Z,12Z)/20:0/20:4(5Z,8Z,11Z,14Z)), de novo triacylglycerol biosynthesis TG(18:4(6Z,9Z,12Z,15Z)/18:3(9Z,12Z,15Z)/18:4(6Z,9Z,12Z,15Z)), and de novo triacylglycerol biosynthesis TG(24:0/20:5(5Z,8Z,11Z,14Z,17Z)/24:0). A hydrogen ion is created when a hydrogen atom loses or gains an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. Due to its extremely high charge density of approximately 2×1010 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it readily hydrates, i.e., bonds quickly. The hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions . Hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions. Under aqueous conditions found in biochemistry, hydrogen ions exist as the hydrated form hydronium, H3O+, but these are often still referred to as hydrogen ions or even protons by biochemists. [Wikipedia])
(R)-3-Hydroxy-hexadecanoic acid
In humans fatty acids are predominantly formed in the liver and adipose tissue, and mammary glands during lactation. (R)-3-Hydroxy-hexadecanoic acid is an intermediate in fatty acid biosynthesis. Specifically, (R)-3-Hydroxy-hexadecanoic acid is converted from 3-Oxo-tetradecanoic acid via fatty-acid Synthase and 3-oxoacyl- [acyl-carrier-protein] reductase. (EC: 2.3.1.85 and EC: 2.3.1.41) [HMDB] In humans fatty acids are predominantly formed in the liver and adipose tissue, and mammary glands during lactation. (R)-3-Hydroxy-hexadecanoic acid is an intermediate in fatty acid biosynthesis. Specifically, (R)-3-Hydroxy-hexadecanoic acid is converted from 3-Oxo-tetradecanoic acid via fatty-acid Synthase and 3-oxoacyl- [acyl-carrier-protein] reductase. (EC: 2.3.1.85 and EC: 2.3.1.41).
3,16-Dihydroxypalmitate
A hydroxy fatty acid anion that is the conjugate base of 3,16-dihydroxypalmitic acid, arising from deprotonation of the carboxy group; major species at pH 7.3.