A natural product that has been considered as a growth factor for some insects.
Compounds based on pyrazino[2,3-d]pyrimidine which is a pyrimidine fused to a pyrazine, containing four NITROGEN atoms.
Compounds based on 2-amino-4-hydroxypteridine.
A pteridine derivative present in body fluids; elevated levels result from immune system activation, malignant disease, allograft rejection, and viral infections. (From Stedman, 26th ed) Neopterin also serves as a precursor in the biosynthesis of biopterin.
(GTP cyclohydrolase I) or GTP 7,8-8,9-dihydrolase (pyrophosphate-forming) (GTP cyclohydrolase II). An enzyme group that hydrolyzes the imidazole ring of GTP, releasing carbon-8 as formate. Two C-N bonds are hydrolyzed and the pentase unit is isomerized. This is the first step in the synthesis of folic acid from GTP. EC 3.5.4.16 (GTP cyclohydrolase I) and EC 3.5.4.25 (GTP cyclohydrolase II).
An enzyme that catalyzes the reduction of 6,7-dihydropteridine to 5,6,7,8-tetrahydropteridine in the presence of NADP+. Defects in the enzyme are a cause of PHENYLKETONURIA II. Formerly listed as EC 1.6.99.7.
Enzymes that catalyze the cleavage of a phosphorus-oxygen bond by means other than hydrolysis or oxidation. EC 4.6.
A group of autosomal recessive disorders marked by a deficiency of the hepatic enzyme PHENYLALANINE HYDROXYLASE or less frequently by reduced activity of DIHYDROPTERIDINE REDUCTASE (i.e., atypical phenylketonuria). Classical phenylketonuria is caused by a severe deficiency of phenylalanine hydroxylase and presents in infancy with developmental delay; SEIZURES; skin HYPOPIGMENTATION; ECZEMA; and demyelination in the central nervous system. (From Adams et al., Principles of Neurology, 6th ed, p952).
A condition characterized by focal DYSTONIA that progresses to involuntary spasmodic contractions of the muscles of the legs, trunk, arms, and face. The hands are often spared, however, sustained axial and limb contractions may lead to a state where the body is grossly contorted. Onset is usually in the first or second decade. Familial patterns of inheritance, primarily autosomal dominant with incomplete penetrance, have been identified. (Adams et al., Principles of Neurology, 6th ed, p1078)
A folic acid derivative used as a rodenticide that has been shown to be teratogenic.
An enzyme of the oxidoreductase class that catalyzes the formation of L-TYROSINE, dihydrobiopterin, and water from L-PHENYLALANINE, tetrahydrobiopterin, and oxygen. Deficiency of this enzyme may cause PHENYLKETONURIAS and PHENYLKETONURIA, MATERNAL. EC 1.14.16.1.
An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.
A form of gram-negative meningitis that tends to occur in neonates, in association with anatomical abnormalities (which feature communication between the meninges and cutaneous structures) or as OPPORTUNISTIC INFECTIONS in association with IMMUNOLOGIC DEFICIENCY SYNDROMES. In premature neonates the clinical presentation may be limited to ANOREXIA; VOMITING; lethargy; or respiratory distress. Full-term infants may have as additional features FEVER; SEIZURES; and bulging of the anterior fontanelle. (From Menkes, Textbook of Child Neurology, 5th ed, pp398-400)
The immediate precursor in the biosynthesis of SEROTONIN from tryptophan. It is used as an antiepileptic and antidepressant.
Purine bases related to hypoxanthine, an intermediate product of uric acid synthesis and a breakdown product of adenine catabolism.
An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.
A subclass of enzymes which includes all dehydrogenases acting on primary and secondary alcohols as well as hemiacetals. They are further classified according to the acceptor which can be NAD+ or NADP+ (subclass 1.1.1), cytochrome (1.1.2), oxygen (1.1.3), quinone (1.1.5), or another acceptor (1.1.99).
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
An antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of TETRAHYDROFOLATE DEHYDROGENASE and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA.
A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in NERVE TISSUE.
A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in ENDOTHELIAL CELLS.
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
An enzyme of the oxidoreductase class that catalyzes the reaction 7,8-dihyrofolate and NADPH to yield 5,6,7,8-tetrahydrofolate and NADPH+, producing reduced folate for amino acid metabolism, purine ring synthesis, and the formation of deoxythymidine monophosphate. Methotrexate and other folic acid antagonists used as chemotherapeutic drugs act by inhibiting this enzyme. (Dorland, 27th ed) EC 1.5.1.3.
Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to METHEMOGLOBIN. In living organisms, SUPEROXIDE DISMUTASE protects the cell from the deleterious effects of superoxides.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Cells that can carry out the process of PHAGOCYTOSIS.
A CALCIUM-independent subtype of nitric oxide synthase that may play a role in immune function. It is an inducible enzyme whose expression is transcriptionally regulated by a variety of CYTOKINES.
Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.
The veins and arteries of the HEART.
Radiography of the vascular system of the heart muscle after injection of a contrast medium.
A chlorinated epoxy compound used as an industrial solvent. It is a strong skin irritant and carcinogen.
Substances which lower blood glucose levels.
Glucose in blood.
A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).
Diminished effectiveness of INSULIN in lowering blood sugar levels: requiring the use of 200 units or more of insulin per day to prevent HYPERGLYCEMIA or KETOSIS.
Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.
Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.
Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.
Enzymes that catalyze the joining of glutamine-derived ammonia and another molecule. The linkage is in the form of a carbon-nitrogen bond. EC 6.3.5.
A 4-hydroxylated metabolite of AFLATOXIN B1, one of the MYCOTOXINS from ASPERGILLUS tainted food. It is associated with LIVER damage and cancer resulting from its P450 activation to the epoxide which alkylates DNA. Toxicity depends on the balance of liver enzymes that activate it (CYTOCHROME P-450) and others that detoxify it (GLUTATHIONE S TRANSFERASE) (Pharmac Ther 50.443 1991). Primates & rat are sensitive while mouse and hamster are tolerant (Canc Res 29.236 1969).
Nitro-phenanthrenes occurring in ARISTOLOCHIACEAE and other plants. They derive from stephanine (APORPHINES) by oxidative ring cleavage. The nitro group is a reactive alkylator (ALKYLATING AGENTS) that binds to biological macromolecules. Ingestion by humans is associated with nephropathy (NEPHRITIS). There is no relationship to the similar named aristolochene (SESQUITERPENES).
Furano-furano-benzopyrans that are produced by ASPERGILLUS from STERIGMATOCYSTIN. They are structurally related to COUMARINS and easily oxidized to an epoxide form to become ALKYLATING AGENTS. Members of the group include AFLATOXIN B1; aflatoxin B2, aflatoxin G1, aflatoxin G2; AFLATOXIN M1; and aflatoxin M2.
A potent hepatotoxic and hepatocarcinogenic mycotoxin produced by the Aspergillus flavus group of fungi. It is also mutagenic, teratogenic, and causes immunosuppression in animals. It is found as a contaminant in peanuts, cottonseed meal, corn, and other grains. The mycotoxin requires epoxidation to aflatoxin B1 2,3-oxide for activation. Microsomal monooxygenases biotransform the toxin to the less toxic metabolites aflatoxin M1 and Q1.
A compound composed of a two CYCLIC PEPTIDES attached to a phenoxazine that is derived from STREPTOMYCES parvullus. It binds to DNA and inhibits RNA synthesis (transcription), with chain elongation more sensitive than initiation, termination, or release. As a result of impaired mRNA production, protein synthesis also declines after dactinomycin therapy. (From AMA Drug Evaluations Annual, 1993, p2015)
Any of the monobasic inorganic or organic acids of sulfur with the general formula RSO(OH). (From McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
A group of 3-hydroxy-4-keto-FLAVONOIDS.
Exclusive legal rights or privileges applied to inventions, plants, etc.
A novel composition, device, or process, independently conceived de novo or derived from a pre-existing model.
Property, such as patents, trademarks, and copyright, that results from creative effort. The Patent and Copyright Clause (Art. 1, Sec. 8, cl. 8) of the United States Constitution provides for promoting the progress of science and useful arts by securing for limited times to authors and inventors, the exclusive right to their respective writings and discoveries. (From Black's Law Dictionary, 5th ed, p1014)
A condition in which the FORAMEN OVALE in the ATRIAL SEPTUM fails to close shortly after birth. This results in abnormal communications between the two upper chambers of the heart. An isolated patent ovale foramen without other structural heart defects is usually of no hemodynamic significance.
Body of knowledge related to the use of organisms, cells or cell-derived constituents for the purpose of developing products which are technically, scientifically and clinically useful. Alteration of biologic function at the molecular level (i.e., GENETIC ENGINEERING) is a central focus; laboratory methods used include TRANSFECTION and CLONING technologies, sequence and structure analysis algorithms, computer databases, and gene and protein structure function analysis and prediction.
Time period from 1701 through 1800 of the common era.
Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.

L-Ascorbic acid potentiates nitric oxide synthesis in endothelial cells. (1/830)

Ascorbic acid has been shown to enhance impaired endothelium-dependent vasodilation in patients with atherosclerosis by a mechanism that is thought to involve protection of nitric oxide (NO) from inactivation by free oxygen radicals. The present study in human endothelial cells from umbilical veins and coronary arteries investigates whether L-ascorbic acid additionally affects cellular NO synthesis. Endothelial cells were incubated for 24 h with 0.1-100 microM ascorbic acid and were subsequently stimulated for 15 min with ionomycin (2 microM) or thrombin (1 unit/ml) in the absence of extracellular ascorbate. Ascorbate pretreatment led to a 3-fold increase of the cellular production of NO measured as the formation of its co-product citrulline and as the accumulation of its effector molecule cGMP. The effect was saturated at 100 microM and followed a similar kinetics as seen for the uptake of ascorbate into the cells. The investigation of the precursor molecule L-gulonolactone and of different ascorbic acid derivatives suggests that the enediol structure of ascorbate is essential for its effect on NO synthesis. Ascorbic acid did not induce the expression of the NO synthase (NOS) protein nor enhance the uptake of the NOS substrate L-arginine into endothelial cells. The ascorbic acid effect was minimal when the citrulline formation was measured in cell lysates from ascorbate-pretreated cells in the presence of known cofactors for NOS activity. However, when the cofactor tetrahydrobiopterin was omitted from the assay, a similar potentiating effect of ascorbate pretreatment as seen in intact cells was demonstrated, suggesting that ascorbic acid may either enhance the availability of tetrahydrobiopterin or increase its affinity for the endothelial NOS. Our data suggest that intracellular ascorbic acid enhances NO synthesis in endothelial cells and that this may explain, in part, the beneficial vascular effects of ascorbic acid.  (+info)

Biopterin derivatives in normal and phenylketonuric patients after oral loads of L-phenylalanine, L-tyrosine, and L-tryptophan. (2/830)

Plasma biopterin derivatives studied in 10 normal and 21 phenylketonuric children showed a significantly high concentration in the latter group. Biopterin derivatives correlated with plasma phenylalanine concentration, but in normal adults given an oral phenylalanine load the rate of increase with phenylalanine differed from that in phenylketonuric patients. A patient with hyperphenylalaninaemia, not due to phenylketonuria, had an abnormal biopterin derivatives response to phenylalanine distinct from that of patients with classical phenylketonuria. This may be a useful investigation to differentiate some variants of phenylketonuria.  (+info)

Protective effects of 5,6,7,8-tetrahydroneopterin against X-ray radiation injury in mice. (3/830)

The protective effects of 5,6,7,8-tetrahydroneopterin (NH4) against radiation injury in mice were studied. (C57BL/6xA/J)F1 (B6A) mice received a single whole-body irradiation dose of 200, 400, 700 or 800 cGy of X-rays. NH4 (30 mg/kg body weight) or phosphate-buffered saline (PBS) was injected intraperitoneally into irradiated mice 10 min before and after the irradiation and again after 6 h. All mice which received the 800 cGy radiation+PBS died between 8 and 11 days after the treatment. In contrast, those which also received NH4 demonstrated a significantly prolonged survival time and 40% lived more than 5 months. Total numbers of thymocytes and spleen cells on day 5 post-irradiation were dramatically reduced in line with the radiation dose. The survival was significantly enhanced by NH4 in treated mice. The proliferation of spleen cells in mice stimulated by concanavalin A (Con A) or lipopolysaccharide (LPS) was also greater in NH4 treated mice. The immune response of survivors 5 months after 800 cGy+NH4 treatments, against Con A, LPS, allogenic mouse, and sheep red blood cells had essentially recovered to the levels of normal mice. These results indicate that NH4 had an important role in modifying radiation injury.  (+info)

Hypoxia inhibits increased ETB receptor-mediated NO synthesis in hypertensive rat lungs. (4/830)

Although hypertensive lungs of chronically hypoxic rats express increased levels of nitric oxide (NO) synthases (NOSs) and produce increased amounts of NO-containing compounds (NOx) during normoxic ventilation, the level of NO production during hypoxic exposure is unclear. Because hypoxia inhibits NO synthesis in normotensive lungs, we investigated whether hypoxic ventilation inhibited NO synthesis in isolated hypertensive lungs and chronically hypoxic rats. Measurement of perfusate NOx concentration in hypertensive lungs from male rats exposed to 4 wk of hypobaric hypoxia showed that basal NOx production was reduced during hypoxic (0% O2) vs. normoxic (21% O2) ventilation. Similarly, plasma NOx concentration was lower in chronically hypoxic rats breathing 10% O2 than in those breathing 21% O2. Hypoxic inhibition of lung NOx production was not prevented by supplementary L-arginine or tetrahydrobiopterin and was not mimicked by inhibition of Ca2+ influx. However, it was mimicked by inhibition of constitutive NOS with NG-monomethyl-L-arginine and chelation of intracellular Ca2+. The endothelin type B-receptor antagonist BQ-788 prevented the increases in NOx production associated with normoxic ventilation in both isolated hypertensive lungs and intact chronically hypoxic rats. These results suggest that a reduced supply of the cosubstrate molecular O2 to NOS counteracts an endothelin type B receptor-mediated stimulation of NO synthesis in hypertensive rat lungs. Thus, despite increased NOS protein in the lungs and pulmonary arteries of chronically hypoxic rats, direct hypoxic inhibition of NO production may contribute to the development of pulmonary hypertension.  (+info)

Enzymatic synthesis of biopterin from D-erythrodihydroneopterin triphosphate by extracts of kidneys from Syrian golden hamsters. (5/830)

An enzyme system was found in either crude homogenates of dialyzed extracts of liver, kidney, lung, and brain from Syrian golden hamsters that catalyzed the synthesis of radioactive 6(L-erythro-1',2'-dihydroxypropyl)pterin (biopterin) from [U-14C]6(D-erythro-1',2',3'-trihydroxypropyl)-7,8-dihydropterin triphosphate (D-erythrolH2neopterin-PPP) preparation. The specific radioactivity of biopterin was found to be comparable to that of D-erythroH2neopterin-PPP. The enzyme system from hamster kidney was purified severalfold by fractionation with ammonium sulfate and with an Ultrogel AcA-34 column. It was demonstrated that (a) NADPH or NADAH was essential and that (b) Mg2+ was stimulatory for the enzymatic synthesis of biopterin from D-erythroH2-NEOPTERIN-PPP. Also GTP and nonphosphorylated neopterins were not converted to biopterin. Although 6-lactyl-7,8-dihydropterin (sepiapterin) was converted to biopterin in the presence of NADPH, sepiapterin was not detected from D-erythroH2neopterin-PPP in the absence of NADPH. A preliminary experiment was performed to identify dihydrobiopterin.  (+info)

Sepiapterin reductase producing L-threo-dihydrobiopterin from Chlorobium tepidum. (6/830)

A novel type of NADPH-dependent sepiapterin reductase, which catalysed uniquely the reduction of sepiapterin to l-threo-dihydrobiopterin, was purified 533-fold from the cytosolic fraction of Chlorobium tepidum, with an overall yield of 3%. The native enzyme had a molecular mass of 55 kDa and SDS/PAGE revealed that the enzyme consists of two subunits with a molecular mass of 26 kDa. The enzyme was optimally active at pH8.8 and 50 degrees C. Apparent Km values for sepiapterin and NADPH were 21 and 6.2 microM, respectively, and the kcat value was 5.0 s-1. Diacetyl could also serve as a substrate, with a Km of 4.0 mM. The inhibitory effects of N-acetylserotonin, N-acetyldopamine and melatonin were very weak. The Ki value of N-acetyldopamine was measured as 400 microM. The N-terminal amino acid sequence was revealed as Met-Lys-His-Ile-Leu-Leu-Ile-Thr-Gly-Ala-Xaa-Lys - Lys - Ile - Xaa - Arg - Ala - Ile - Ala - Leu - Glu - Xaa - Ala - Arg - Xaa-Xaa-Xaa-His-His-His-, which shared relatively high sequence similarity with other sepiapterin reductases.  (+info)

Activation of neuronal nitric-oxide synthase by the 5-methyl analog of tetrahydrobiopterin. Functional evidence against reductive oxygen activation by the pterin cofactor. (7/830)

Tetrahydrobiopterin ((6R)-5,6,7,8-tetrahydro-L-biopterin (H4biopterin)) is an essential cofactor of nitric-oxide synthases (NOSs), but its role in enzyme function is not known. Binding of the pterin affects the electronic structure of the prosthetic heme group in the oxygenase domain and results in a pronounced stabilization of the active homodimeric structure of the protein. However, these allosteric effects are also produced by the potent pterin antagonist of NOS, 4-amino-H4biopterin, suggesting that the natural cofactor has an additional, as yet unknown catalytic function. Here we show that the 5-methyl analog of H4biopterin, which does not react with O2, is a functionally active pterin cofactor of neuronal NOS. Activation of the H4biopterin-free enzyme occurred in a biphasic manner with half-maximally effective concentrations of approximately 0.2 microM and 10 mM 5-methyl-H4biopterin. Thus, the affinity of the 5-methyl compound was 3 orders of magnitude lower than that of the natural cofactor, allowing the direct demonstration of the functional anticooperativity of the two pterin binding sites of dimeric NOS. In contrast to H4biopterin, which inactivates nitric oxide (NO) through nonenzymatic superoxide formation, up to 1 mM of the 5-methyl derivative did not consume O2 and had no effect on NO steady-state concentrations measured electrochemically with a Clark-type NO electrode. Therefore, reconstitution with 5-methyl-H4biopterin allowed, for the first time, the detection of enzymatic NO formation in the absence of superoxide or NO scavengers. These results unequivocally identify free NO as a NOS product and indicate that reductive O2 activation by the pterin cofactor is not essential to NO biosynthesis.  (+info)

Functionally important residues tyrosine-171 and serine-158 in sepiapterin reductase. (8/830)

The active site of sepiapterin reductase (SPR), which is a member of the NADP(H)-preferring short-chain dehydrogenase/reductase (SDR) family and acts as the terminal enzyme in the biosynthetic pathway of tetrahydrobiopterin cofactor (BH4), was investigated by truncation and site-directed mutagenesis. The truncation mutants showed that N-terminal and C-terminal residues contribute to bind coenzyme and substrate, respectively. The mutant rSPRA29V showed decreased activity; however, the A-X-L-L-S sequence, which has been reported as a putative pterin binding site, was estimated to preferably work as a component in the region for binding coenzyme rather than substrate. Site-directed mutants of rSPRS158D, rSPRY171V, and rSPRK175I showed low, but significant, activity having similar Km values and kcat/Km values less than 25%, for both sepiapterin and NADPH. Both amino acids Tyr-171 and Ser-158 are located within a similar distance to the carbonyl group of the substrate in the crystal structure of mouse SPR, and the double point mutant rSPRY171V+S158D was indicated to be inactive. These results showed that Ser-158, Tyr-171, and Lys-175 contributed to the catalytic activity of SPR, and both Tyr-171 and Ser-158 are simultaneously necessary on proton transfer to the carbonyl functional groups of substrate.  (+info)

Tetrahydrobiopterin deficiency (THBD, BH4D), also called THB or BH4 deficiency, is a rare metabolic disorder that increases the blood levels of phenylalanine. Phenylalanine is an amino acid obtained through the diet. It is found in all proteins and in some artificial sweeteners. If tetrahydrobiopterin deficiency is not treated, excess phenylalanine can build up to harmful levels in the body, causing intellectual disability and other serious health problems. High levels of phenylalanine are present from infancy in people with untreated tetrahydrobiopterin (THB, BH4) deficiency. The resulting signs and symptoms range from mild to severe. Mild complications may include temporary low muscle tone. Severe complications include intellectual disability, movement disorders, difficulty swallowing, seizures, behavioral problems, progressive problems with development, and an inability to control body temperature. It was first characterized in 1975. This condition is inherited in an autosomal recessive ...
Tetrahydrobiopterin is a cofactor in hydroxylation reactions, including phenylalanine 4-monooxygenase, tyrosine 3-monooxygenase, tryptophan 5-monooxygenase, alkyl glycol ether monooxygenase and nitric oxide synthase. Determination of its biosynthesis is carried out to diagnose inherited diseases leading to partial defects in tetrahydrobiopterin synthesis. In addition, tetrahydrobiopterin synthesis is induced by proinflammatory cytokines, and intracellular levels of tetrahydro-biopterin in many cases limit the activity of tetrahydrobiopterin-dependent reactions, such as nitric oxide synthase in intact cells. Biosynthesis of tetrahydrobiopterin from guanosine 5-triphosphate (GTP) requires the action of three enzymes, GTP-cyclohydrolase I (E.C. 3.5.4.16), 6-pyruvoyl tetrahydropterin synthase (EC, 4.6.1.10) and sepiapterin reductase (E.C. 1.1.1.153). Methods for quantification of biopterin and related pteridines in biological matrices by HPLC and application of these for determining the activity of ...
B Chronic oral tetrahydrobiopterin treatment in patients with coronary artery disease elevates total biopterin levels but does not improve biopterin redox status or vascular function: a randomised placebo-controlled trial ...
This is the first study to examine the effect of increased intracellular levels of tetrahydrobiopterin on endothelial function in isolated arteries. As an experimental model, we used canine middle cerebral arteries incubated with sepiapterin. The major new findings are that (1) sepiapterin stimulates tetrahydrobiopterin production in endothelial and smooth muscle cells of intact arteries and (2) high tissue levels of tetrahydrobiopterin have an inhibitory effect on endothelium-dependent relaxations, whereas (3) in the presence of superoxide dismutase, tetrahydrobiopterin augments endothelium-dependent relaxations.. Under basal conditions, measurements of tetrahydrobiopterin levels revealed a detectable amount of NO synthase cofactor in cerebral arterial wall preparations incubated for 24 hours. Similar levels were also detected in freshly isolated basilar arteries,16 suggesting that tetrahydrobiopterin production had not been affected by incubation in MEM. The removal of endothelial cells caused ...
Overproduction of nitric oxide (NO) is thought to be a key mediator of the vascular dysfunction and severe hypotension in patients with endotoxaemia and septic shock. The contribution of NO produced directly in the vasculature by endothelial cells to the hypotension seen in these conditions, vs. the broader systemic increase in NO, is unclear. To determine the specific role of endothelium derived NO in lipopolysaccharide (LPS)-induced vascular dysfunction we administered LPS to mice deficient in endothelial cell tetrahydrobiopterin (BH4), the essential co-factor for NO production by NOS enzymes. Mice deficient in endothelial BH4 production, through loss of the essential biosynthesis enzyme Gch1 (Gch1(fl/fl)Tie2cre mice) received a 24hour challenge with LPS or saline control. In vivo LPS treatment increased vascular GTP cyclohydrolase and BH4 levels in aortas, lungs and hearts, but this increase was significantly attenuated in Gch1(fl/fl)Tie2cre mice, which were also partially protected from the LPS
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TY - JOUR. T1 - Transcribing the cross-talk of cytokine-induced tetrahydrobiopterin synthesis in endothelial cells. AU - Peterson, Timothy E.. AU - Katusic, Zvonimir S.. PY - 2005/2/4. Y1 - 2005/2/4. KW - Interferon-γ. KW - Nitric oxide. KW - Nitric oxide synthase. KW - Tumor necrosis factor-α. UR - http://www.scopus.com/inward/record.url?scp=13444271566&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=13444271566&partnerID=8YFLogxK. U2 - 10.1161/01.RES.0000156078.12390.44. DO - 10.1161/01.RES.0000156078.12390.44. M3 - Editorial. C2 - 15692091. AN - SCOPUS:13444271566. VL - 96. SP - 141. EP - 143. JO - Circulation Research. JF - Circulation Research. SN - 0009-7330. IS - 2. ER - ...
SPR Deficiency is caused by mutations in the SPR gene. The SPR gene provides instructions for making the enzyme sepiapterin reductase. Specifically, sepiapterin reductase is responsible for the last step in the production of tetrahydrobiopterin. Most SPR gene mutations result in an enzyme with little or no function.. A nonfunctional sepiapterin reductase gene leads to a lack of tetrahydrobiopterin which causes a disruption in neurotransmitter metabolism. SPR Deficiency is due to an autosomal recessive inheritance. In this type of inheritance pattern there are two mutated copies of the gene that causes the disorder. A person with SPR deficiency usually has unaffected parents (no symptoms) who each carry a single copy of the mutated gene and are referred to as carriers.. Autosomal recessive disorders are typically not seen in every generation of an affected family. When two people who are carriers of an autosomal recessive condition have a child, there is a 25% (1 in 4) chance that the child will ...
We use cookies to ensure that we give you the best experience on our website. If you click Continue well assume that you are happy to receive all cookies and you wont see this message again. Click Find out more for information on how to change your cookie settings ...
We use cookies to ensure that we give you the best experience on our website. If you click Continue well assume that you are happy to receive all cookies and you wont see this message again. Click Find out more for information on how to change your cookie settings ...
ESWL is an effective, non-invasive therapy utilized to fragment stones in the kidney and subsequently be cleared in the urinary tract. Although lithotripsy provides a safer alternative to invasive treatments for removing stones, ESWL may cause vasoconstriction after ESWL treatment, reducing renal blood flow, which can cause kidney damage leading to acute to chronic hypertension clinically. This may be due to kidney vascular endothelial dysfunction, which is characterized as increased oxidative stress and decreased endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) bioavailability. We hypothesized that ESWL would decrease NO and increase hydrogen peroxide (H2O2) in rat renal veins. Rats given tetrahydrobiopterin (BH4), the essential cofactor of eNOS coupling, would cause a decrease in H2O2 release and increase in NO release compared to ESWL + saline controls. On the contrary, when dihydrobiopterin (BH2), the cofactor for eNOS uncoupling, is given at the end of ESWL treatment we predict an
TY - JOUR. T1 - Effect of tetrahydrobiopterin on selective endothelial dysfunction of epicardial porcine coronary arteries induced by cardiopulmonary bypass. AU - Stevens, Louis Mathieu. AU - Fortier, Simon. AU - Aubin, Marie Claude. AU - El-Hamamsy, Ismail. AU - Maltais, Simon. AU - Carrier, Michel. AU - Perrault, Louis P.. PY - 2006/9/1. Y1 - 2006/9/1. N2 - Background: We hypothesized that cardiopulmonary bypass induces a selective alteration of the coronary arterial endothelial cell signal transduction which could be explained by a state of depletion and/or decreased activity of endogenous tetrahydrobiopterin (BH4). The aim of this study was to assess the effects of cardiopulmonary bypass and BH4 on the endothelial function of epicardial coronary arteries in a swine model of cardiopulmonary bypass. Methods: Swine underwent 90 min of cardiopulmonary bypass alone (N = 19) or in association with a brief cardioplegic arrest with (N = 6) or without (N = 5) in vivo BH4 administration, followed by a ...
Tetrahydrobiopterin (BH4) is an essential cofactor for the aromatic amino acid hydroxylases, alkylglycerol monooxygenase, and nitric oxide synthases (NOS). Inborn errors of BH4 metabolism lead to severe insufficiency of brain monoamine neurotransmitters while augmentation of BH4 by supplementation or stimulation of its biosynthesis is thought to ameliorate endothelial NOS (eNOS) dysfunction, to protect from (cardio-) vascular disease and/or prevent obesity and development of the metabolic syndrome. We have previously reported that homozygous knock-out mice for the 6-pyruvolytetrahydropterin synthase (PTPS; Pts-ko/ko) mice with no BH4 biosynthesis die after birth. Here we generated a Pts-knock-in (Pts-ki) allele expressing the murine PTPS-p.Arg15Cys with low residual activity (15% of wild-type in vitro) and investigated homozygous (Pts-ki/ki) and compound heterozygous (Pts-ki/ko) mutants. All mice showed normal viability and depending on the severity of the Pts alleles exhibited up to 90% reduction of
Biopterin is a coenzyme thats used to make several important neurotransmitters in the body. Problems with biopterin levels can...
In this study, we describe a new double-transgenic mouse model in which endothelial-targeted overexpression of GTPCH leads to increased endothelial BH4 levels in mice with endothelial-targeted eNOS overexpression. We used this model to investigate the role of BH4 in the regulation of eNOS coupling in vivo, specifically in the absence of pathological oxidative stress associated with vascular disease states.6 The major findings in this study are as follows. First, eNOS protein levels are markedly elevated in eNOS-Tg and eNOS/GCH-Tg mice but not in GCH-Tg animals, although the proportion of eNOS dimer to monomer is depleted only in eNOS-Tg aortas. Second, endothelial-specific overexpression of GTPCH is sufficient to increase vascular BH4 levels in GCH-Tg and in eNOS/GCH-Tg aortas, whereas BH4 levels are depleted in eNOS-Tg aortas. Third, this increase in BH4 is sufficient to augment vascular eNOS enzymatic activity even in GCH-Tg mice, which have unchanged eNOS protein levels. Indeed, eNOS activity ...
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Dihydrobiopterin (BH2) is a pteridine compound produced in the synthesis of L-DOPA, dopamine, norepinephrine and epinephrine. It is restored to the required cofactor tetrahydrobiopterin by dihydrobiopterin reductase. Pteridine ...
BACKGROUND Nitric oxide synthase uncoupling occurs under conditions of oxidative stress modifying the enzymes function so it generates superoxide rather than nitric oxide. Nitric oxide synthase uncoupling occurs with chronic pressure overload, and both are ameliorated by exogenous tetrahydrobiopterin (BH4)-a cofactor required for normal nitric oxide synthase function-supporting a pathophysiological link. Genetically augmenting BH4 synthesis in endothelial cells fails to replicate this benefit, indicating that other cell types dominate the effects of exogenous BH4 administration. We tested whether the primary cellular target of BH4 is the cardiomyocyte or whether other novel mechanisms are invoked. METHODS AND RESULTS Mice with cardiomyocyte-specific overexpression of GTP cyclohydrolase 1 (mGCH1) and wild-type littermates underwent transverse aortic constriction. The mGCH1 mice had markedly increased myocardial BH4 and, unlike wild type, maintained nitric oxide synthase coupling after transverse
The diagnosis and long-term effects of treatment of two cases of sepiapterin reductase deficiency (SRD) are reported from Service de Neuropediatrie, CHU Montpellier, France; University de Sherbrooke, Quebec, Canada; and centers in Germany and Switzerland. Patient 1, a male with first-cousin Turkish parents, presented with a prolonged afebrile seizure at 6 months of age. Progressive global delay, intermittent dystonic movements, and oculogyric crises followed. EEG, MRI, and routine metabolic tests were normal. At 18 months he had developed generalized spasticity, and by 7 years of age, symptoms showed a diurnal variation, with ability to walk in the mornings and requiring a wheelchair by afternoon. Patient 2, a female born of nonconsanguineous Caucasian parents, presented with delayed psychomotor signs at 5 months, generalized hypotonia, and oculogyric crises. At one year dystonic movements and swallowing difficulties developed. She walked at 3 years, hypotonia was replaced by spasticity, and her ...
Inadequate tetrahydrobiopterin (BH4) concentration has been linked to impaired endothelial NO synthase (eNOS) activity and to loss of endothelial function in vascular conditions such as hypercholesterolemia. Blau and Thöny correctly contend that despite the critical importance of BH4 in NO formation from eNOS, patients with BH4 deficiency typically show no evidence of vascular disease. Studies that have evaluated the effects of BH4 supplementation have further observed divergent effects in animal models as well as in humans, with some studies reporting beneficial or no effects and a few reporting actual worsening of vascular function.1 We have recently presented an alternative hypothesis that may reconcile these apparently contradictory findings. This is that the relative concentrations of fully reduced (BH4) and oxidized forms of tetrahydrobiopterin (BH2), rather than the absolute concentration of BH4, are what governs the nature of products generated from eNOS.2 At low BH4 or high BH2 ...
TY - JOUR. T1 - Acute Tetrahydrobiopterin Improves Endothelial Function in Patients With COPD. AU - Rodriguez-Miguelez, Paula. AU - Gregg, Justin. AU - Seigler, Nichole. AU - Bass, Leon. AU - Thomas, Jeffrey. AU - Pollock, Jennifer S.. AU - Sullivan, Jennifer C. AU - Dillard, Thomas A. AU - Harris, Ryan A.. PY - 2018/9/1. Y1 - 2018/9/1. N2 - Background: Cardiovascular diseases represent a hallmark characteristic in COPD, and endothelial dysfunction has been observed in these patients. Tetrahydrobiopterin (BH4) is an essential cofactor for nitric oxide (NO) synthesis and a regulator of endothelial function. The goal of this study was to test the hypothesis that a single dose of BH4 would improve endothelial function in patients with COPD via an increase in NO bioavailability. Methods: Seventeen patients with COPD completed a randomized, double-blind, placebo (PLC)-controlled, crossover trial with an acute dose of either BH4 (Kuvan; BioMarin Pharmaceutical Inc) or PLC. Flow-mediated dilation ...
BACKGROUND: Reduced availability of tetrahydrobiopterin (BH(4)), an essential cofactor of nitric oxide (NO) synthase (NOS), decreases NO production and increases reactive oxygen species. Both mechanisms contribute to atherosclerotic vascular disease. Although acute supplementation of BH(4) improves endothelial dysfunction, the effect of chronic BH(4) in humans is unknown. OBJECTIVE: To investigate the effect of chronic BH(4) supplementation on endothelial function and oxidative stress in hypercholesterolaemia. DESIGN: Randomised double-blind, placebo-controlled trial. SETTING: University Hospital. PATIENTS: 22 hypercholesterolaemic patients (low-density lipoprotein (LDL) |4.5 mmol/l) were randomised to 4 weeks of oral BH(4) (400 mg twice daily) or placebo. Age-matched healthy volunteers served as controls. MAIN OUTCOME MEASURES: Endothelium-dependent and -independent vasodilatation was assessed by venous occlusion plethysmography. To elucidate the mechanisms of BH(4) effect, NO release and superoxide
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The International Conference on Tetrahydrobiopterin, PKU, and NOS Will take place March 23-28, 2008 in St. Moritz - Champfér, Switzerland For more information, visit http://www.pku-bh4.com/index.asp Thank you very much in advance for your contributions to this blog (Click on login to register and post a comment). Click this link to see the most recent online […]. ...
SPR antibody [N2C3] (sepiapterin reductase (7,8-dihydrobiopterin:NADP+ oxidoreductase)) for ICC/IF, IHC-P, IP, WB. Anti-SPR pAb (GTX113552) is tested in Human, Mouse samples. 100% Ab-Assurance.
You have two copies of a GCH1 variant associated with lower levels of tetrahydrobiopterin (BH4) and total biopterins. BH4 is used in the production of several neurotransmitters, including serotonin and dopamine. While many people carry this with no obvious ill effects, it does seem noteworthy. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699614/ reports median plasma BH4 levels in patients with this genotype were reduced by approximately 80%. Several potentially serious health issues could result from an 80% reduction in BH4 levels. There may not be enough BH4 to convert phenylalanine to tyrosine. Therefore, phenylalanine can build up in body tissue and cause health issues (like high blood pressure). But, now there may not be enough tyrosine, which is needed to create dopamine. And so then there may not be enough dopamine, which can possibly lead to symptoms SIMILAR to conditions like Fibromyalgia and Parkinsons (but not actually Parkinsons). People who have low levels of tyrosine, and ...
Methyl-folate is pretty busy. It doesnt work alone; however. Vitamins B2, B6, and B12 as well as cofactors like magnesium all help support the functioning of this pivotal cycle in the body.. Maybe Shes Born With It. MTHFR is just one example of a gene for which we can test for decently studied variants at a local lab. There are two common variants to this gene wherein replacements of single nucleotides results in lesser functioning. These variants are inherited.. C677T - one bad copy means your enzyme is functioning at 70% and two means youre down to 30%. This mutation has been associated with cardiovascular and psychiatric pathology and its impact is often assessed through screening of homocysteine.. And.... A1298C - this variant has been less well studied but is estimated to confer 70% functioning when both copies are mutated. This mutation has been implicated in the production of neurotransmitters (because of its involvement in making biopterin, and important cofactor), and breakdown of ...
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Im not sure where to post this type of question, couldnt find an exact match, so forgive me if its in the wrong place. I havent been on BH for a while. But I find myself unexpectedly pregnant with our fourth (!!!!) baby and we are not - page 4
Is there anyone else out there on BH land that is also waiting to TTC later this year/early next year? Curious to hear why others are waiting and perhaps we can all help make the time go faster together!!! - page 66
以前我一直在買專櫃的衣服,認為要現場挑衣服才有保障,不太敢在網路上買衣服,因為害怕收到貨時與圖色差太大,或是怕…
Guppy is a popular ornamental fish owing to its diverse body and fin coloration. More than 40 established color varieties have been selectively bred. The complementary DNAs for 2 enzymes that are involved in the de novo synthesis of pteridines and purines, which are important for the production of color pigments, were cloned from the caudal fin. Two cDNA isoforms for 6-pyruvoyl tetrahydropterin synthase (PTPS), with an open reading frame of 130 and 147 amino acids, respectively, were cloned from the Red Tail variety. The deduced amino acid sequence of the longer isoform shows an overall identity of about 65% to the mammalian PTPS sequences. The cDNA for xanthine dehydrogenase (XDH) was cloned from the Yellow Tail variety, and consists of an open reading frame of 1331 amino acids. Although it shows a higher overall identity to bovine aldehyde oxidase (AO; 54%) than to chicken XDH (51%), it has a NAD-binding domain that is specific to XDHs. Northern blot analysis indicated that both PTPS and XDH ...
Tetrahydrobiopterin (BH4) cofactor is essential for various processes, and is present in probably every cell or tissue of higher organisms. BH4 is required for various enzyme activities, and for less defined functions at the cellular level. The pathway for the de novo biosynthesis of BH4 from GTP involves GTP cyclohydrolase I, 6-pyruvoyl-tetrahydropterin synthase and sepiapterin reductase. Cofactor regeneration requires pterin-4a-carbinolamine dehydratase and dihydropteridine reductase. Based on gene cloning, recombinant expression, mutagenesis studies, structural analysis of crystals and NMR studies, reaction mechanisms for the biosynthetic and recycling enzymes were proposed. With regard to the regulation of cofactor biosynthesis, the major controlling point is GTP cyclohydrolase I, the expression of which may be under the control of cytokine induction. In the liver at least, activity is inhibited by BH4, but stimulated by phenylalanine through the GTP cyclohydrolase I feedback regulatory ...
Excessive intimal hyperplasia, the principal cause of PCI failure, is associated with reduced endothelial nitric oxide (NO) bioavailability. Tetrahydrobiopterin (BH4) is a required cofactor for NO synthesis by endothelial nitric oxide synthase (eNOS). We investigated the importance of BH4 in regulating intimal hyperplasia using a transgenic mouse with endothelial overexpression of the rate-limiting enzyme in BH4 synthesis, GTP-cyclohydrolase I (GCH). Angioplasty and stenting was performed on aortic segments from donor transgenic mice crossed onto ApoE-KO background (GCH-Tg/ApoE-KO) or their ApoE-KO littermates (n=16), using a novel model of stenting in mice where the stented donor aortic segment is grafted into the carotid artery of isogenic recipients. Aortic BH4 levels were 8-fold higher in GCH-Tg/ApoE-KO mice compared with ApoE-KO controls. (P,0.01). Despite equal stent expansion and injury scores, intimal hyperplasia was reduced by 47% (P,0.001) in GCH-Tg/ApoE-KO mice. Aortic NO synthesis, ...
AIMS: Clinical markers of cardiac autonomic function, such as heart rate and response to exercise, are important predictors of cardiovascular risk. Tetrahydrobiopterin (BH4) is a required cofactor for enzymes with roles in cardiac autonomic function, including tyrosine hydroxylase and nitric oxide synthase. Synthesis of BH4 is regulated by GTP cyclohydrolase I (GTPCH), encoded by GCH1. Recent clinical studies report associations between GCH1 variants and increased heart rate, but the mechanistic importance of GCH1 and BH4 in autonomic function remains unclear. We investigate the effect of BH4 deficiency on the autonomic regulation of heart rate in the hph-1 mouse model of BH4 deficiency. METHODS AND RESULTS: In the hph-1 mouse, reduced cardiac GCH1 expression, GTPCH enzymatic activity, and BH4 were associated with increased resting heart rate; blood pressure was not different. Exercise training decreased resting heart rate, but hph-1 mice retained a relative tachycardia. Vagal nerve stimulation in vitro
Endothelial dysfunction in vascular disease states is associated with reduced NO bioactivity and increased superoxide (O2 ) production. Some data suggest that an important mechanism underlying endothelial dysfunction is endothelial NO synthase (eNOS) uncoupling, whereby eNOS generates O2 rather than NO, possibly because of a mismatch between eNOS protein and its cofactor tetrahydrobiopterin (BH4). However, the mechanistic relationship between BH4 availability and eNOS coupling in vivo remains undefined because no studies have investigated the regulation of eNOS by BH4 in the absence of vascular disease states that cause pathological oxidative stress through multiple mechanisms. We investigated the stoichiometry of BH4-eNOS interactions in vivo by crossing endothelialtargeted eNOS transgenic (eNOS-Tg) mice with mice overexpressing endothelial GTP cyclohydrolase 1 (GCH-Tg), the rate-limiting enzyme in BH4 synthesis. eNOS protein was increased 8-fold in eNOS-Tg and eNOS/GCH-Tg mice compared with wild type.
Initially immunohistochemistry staining of tissue arrays from 71 breast cancer patients for GTPCH revealed that 60% of them are strongly positive in cancer cells and 50% positive in both stroma and vessels. We co-cultured MDA231-GFP breast cancer cells with genetically modified murine fibroblasts (GCHtet-off), which express GTPCH under doxycycline (Dox) control, and found that the fibroblast-derived BH4 promoted MDA231-GFP clonogenesis, cell proliferation and migration in cultures. These augmentations were prevented by Dox when GTPCH was switched off, or by the GTPCH inhibitor-DAHP in vitro. Furthermore, cotransplantation of MDA231-GFP and GCHtet-off in SCID mice demonstrated BH4 synthesis in the fibroblasts significantly increased MDA231-GFP tumorigenesis, the tumour cell proliferation, invasiveness to smooth muscles and angiogenesis in comparison to MDA231-GFP alone or with cotransplantation of the control, Tet-off-EV. Conversely, both switching off GTPCH expression by Dox and inhibiting its ...
Tetrahydrobiopterin (BH4) is an essential cofactor for endothelial nitric oxide synthase (eNOS) function and nitric oxide (NO) generation. Augmentation of BH4 levels can prevent eNOS uncoupling and improve endothelial dysfunction in vascular disease states. However, the physiological requirement for de-novo endothelial cell BH4 biosynthesis in eNOS function remains unclear. We generated a novel mouse model with endothelial cell-specific deletion of GCH1, encoding GTP cyclohydrolase 1, an essential enzyme for BH4 biosynthesis, to test the cell-autonomous requirement for endothelial BH4 biosynthesis in vivo.. Mice with a floxed GCH1 allele (GCH1fl/fl) were crossed with Tie2cre mice to delete GCH1 in endothelial cells. GCH1fl/flTie2cre mice demonstrated virtually absent NO bioactivity and significantly greater O2•- production. GCH1fl/flTie2cre aortas and mesenteric arteries had enhanced vasoconstriction to phenylephrine and impaired endothelium-dependent vasodilatations to acetylcholine and ...
BACKGROUND: Increased serum neopterin had been described in older age two decades ago. Neopterin is a biomarker of systemic adaptive immune activation that could be potentially implicated in metabolic syndrome (MetS). Measurements of waist circumference, triglycerides, high-density lipoprotein cholesterol (HDLC), systolic and diastolic blood pressure, glycated hemoglobin as components of MetS definition, and plasma total neopterin concentrations were performed in 594 participants recruited in the European Prospective Investigation into Cancer and Nutrition (EPIC). RESULTS: Higher total neopterin concentrations were associated with reduced HDLC (9.7 %, p | 0.01 for men and 9.2 %, p | 0.01 for women), whereas no association was observed with the rest of the MetS components as well as with MetS overall (per 10 nmol/L: OR = 1.42, 95 % CI = 0.85-2.39 for men and OR = 1.38, 95 % CI = 0.79-2.43). CONCLUSIONS: These data suggest that high total neopterin concentrations are cross-sectionally associated with
The nitric oxide synthases are dimeric enzymes in which the intersubunit contacts are formed by the P-450-haem-containing, tetrahydrobiopterin-dependent oxygenase domain. The dimerization of the neuronal isoenzyme was shown previously to be triggered by Fe-protoporphyrin IX (haemin). We report for the first time the reactivation of the haem-deficient neuronal isoenzyme (from rat, expressed in a baculovirus/insect cell system) after haem reconstitution. We further examined the reconstitution of the enzyme with protoporphyrin IX (PPIX) and its Mn and Co complexes. All of these porphyrins inserted into the haem pocket, as assessed by quenching of intrinsic protein fluorescence. In addition to haemin, MnPPIX stimulated dimerization, as measured by gel filtration and by cross-linking with glutaraldehyde. In contrast, neither CoPPIX nor PPIX stimulated dimerization. The absorbance spectra of the reconstituted enzymes were measured and compared with published results on P-450 enzymes reconstituted with ...
This study examined whether maintaining the intrarenal levels of GTPCH I and BH4 inhibited the progression of diabetic nephropathy and whether the intrarenal levels of these biomolecules could be ameliorated by metformin, which is an AMPK activator. Intrarenal GTPCH I level was decreased in mice with diabetic nephropathy but was increased in mice overexpressing GTPCH I. Higher levels of GTPCH I and BH4 reduced glomerular ROS production and improved glomerular hyperpermeability and urinary albumin excretion. Metformin has been suggested to inhibit degradation of renal GTPCH I and to exert a renal protective effect. Collectively, these results show that reducing levels of intrarenal GTPCH I is profoundly involved in the progression of diabetic nephropathy, which is recognized as a manifestation of diabetic microangiopathy, and that maintaining GTPCH I activity might delay the progression of this condition.. Our results showed that there was no significant difference in the intrarenal BH4 levels in ...
Dihydrofolate reductase (DHFR) is a critical enzyme in folate metabolism and an important target of antineoplastic, antimicrobial, and antiinflammatory drugs. We describe three individuals from two families with a recessive inborn error of metabolism, characterized by megaloblastic anemia and/or pancytopenia, severe cerebral folate deficiency, and cerebral tetrahydrobiopterin deficiency due to a germline missense mutation in DHFR, resulting in profound enzyme deficiency. We show that cerebral folate levels, anemia, and pancytopenia of DHFR deficiency can be corrected by treatment with folinic acid. The characterization of this disorder provides evidence for the link between DHFR and metabolism of cerebral tetrahydrobiopterin, which is required for the formation of dopamine, serotonin, and norepinephrine and for the hydroxylation of aromatic amino acids. Moreover, this relationship provides insight into the role of folates in neurological conditions, including depression, Alzheimer disease, and ...
Dihydrofolate reductase (DHFR) is a critical enzyme in folate metabolism and an important target of antineoplastic, antimicrobial, and antiinflammatory drugs. We describe three individuals from two families with a recessive inborn error of metabolism, characterized by megaloblastic anemia and/or pancytopenia, severe cerebral folate deficiency, and cerebral tetrahydrobiopterin deficiency due to a germline missense mutation in DHFR, resulting in profound enzyme deficiency. We show that cerebral folate levels, anemia, and pancytopenia of DHFR deficiency can be corrected by treatment with folinic acid. The characterization of this disorder provides evidence for the link between DHFR and metabolism of cerebral tetrahydrobiopterin, which is required for the formation of dopamine, serotonin, and norepinephrine and for the hydroxylation of aromatic amino acids. Moreover, this relationship provides insight into the role of folates in neurological conditions, including depression, Alzheimer disease, and ...
A recent study suggests that potentially treatable metabolic abnormalities in the central nervous system may underlie a large proportion of cases of severe, treatment-resistant depression. These abnormalities, such as folate deficiency in the cerebrospinal fluid, are not screened for regularly, as they require a spinal tap to diagnose.. Researchers led by Lisa A. Pan were inspired to assess metabolic function in people with treatment-resistant depression after a young patient with severe, persistent depression who had attempted suicide several times improved dramatically after being diagnosed with a tetrahydrobiopterin deficiency in his cerebrospinal fluid and treated for the deficiency. Tetrahydrobiopterin is critical to the production of monoamine neurotransmitters.. The researchers carried out a case-control study of 33 teen and young adult patients who had had treatment-resistant depression since childhood and 16 healthy control participants. Twenty-one of the 33 patients with severe ...
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Tetrahydrobiopterin (BH4) is an essential co-factor for NO production from NOS enzymes. When BH4 levels become limiting these enzymes can become un-coupled, leading to superoxide production. GTP cyclohydrolase I (GTPCH), encoded by GCH1, is an essential enzyme in the biosynthesis of BH4. BH4 deficiency has been been shown to cause endothelial dysfunction and to exacerbate atherosclerosis in experimental models. However, the role of BH4 in regulating iNOS activity in leukocytes, and the potential impact of this on atherosclerosis is less clear. We have utilised a novel transgenic mouse to address the role of BH4 and iNOS in macrophage biology.. We designed mice harbouring a floxed portion of the GCH1 locus within the active site of the enzyme (GCHfl/fl mice). We crossed these with mice expressing the cre enzyme under control of the Tie2 promoter (GCHfl/fl Tie2cre). Cre expression causes efficient excision of the floxed allele in all leukocytes and endothelial cells, as detected by PCR for the ...
HIV-1 invades the central nervous system (CNS) in the context of acute infection, persists thereafter in the absence of treatment, and leads to chronic intrathecal immunoactivation that can be measured by the macrophage activation marker, neopterin, in cerebrospinal fluid (CSF). In this review we describe our experience with CSF neopterin measurements in 382 untreated HIV-infected patients across the spectrum of immunosuppression and HIV-related neurological diseases, in 73 untreated AIDS patients with opportunistic CNS infections, and in 233 treated patients. In untreated patients, CSF neopterin concentrations are almost always elevated and increase progressively as immunosuppression worsens and blood CD4 cell counts fall. However, patients with HIV dementia exhibit particularly high CSF neopterin concentrations, above those of patients without neurological disease, though patients with CNS opportunistic infections, including CMV encephalitis and cryptococcal meningitis, also exhibit high levels of CSF
TY - JOUR. T1 - C-terminus of heat shock protein 70-interacting protein-dependent GTP cyclohydrolase I degradation in lambs with increased pulmonary blood flow. AU - Sun, Xutong. AU - Fratz, Sohrab. AU - Sharma, Shruti. AU - Hou, Yali. AU - Rafikov, Ruslan. AU - Kumar, Sanjiv. AU - Rehmani, Imran. AU - Tian, Jing. AU - Smith, Anita. AU - Schreiber, Christian. AU - Reiser, Judith. AU - Naumann, Susanne. AU - Haag, Sebastian. AU - Hess, John. AU - Catravas, John D.. AU - Patterson, Cam. AU - Fineman, Jeffery R.. AU - Black, Stephen M.. PY - 2011/7/1. Y1 - 2011/7/1. N2 - We showed that nitric oxide (NO) signaling is decreased in the pulmonary vasculature before the development of endothelial dysfunction in a lamb model of congenital heart disease and increased pulmonary blood flow (Shunt). The elucidation of the molecular mechanism by which this occurs was the purpose of this study. Here, we demonstrate that concentrations of the endogenous NO synthase (NOS) inhibitor, asymmetric dimethylarginine ...
Sigma-Aldrich offers abstracts and full-text articles by [Anna Starr, Claire A Sand, Lamia Heikal, Peter D Kelly, Domenico Spina, Mark Crabtree, Keith M Channon, James M Leiper, Manasi Nandi].
Germanys Merck KGaA has submitted an application with European regulators to get marketing approval for sapropterin as an oral treatment for hyperphenylalaninemia (HPA). - News - PharmaTimes
Classical activation of macrophages (M(LPS+IFNγ)) elicits the expression of inducible nitric oxide synthase (iNOS), generating large amounts of NO and inhibiting mitochondrial respiration. Upregulation of glycolysis and a disrupted tricarboxylic acid (TCA) cycle underpin this switch to a pro-inflammatory phenotype. We show that the NOS cofactor tetrahydrobiopterin (BH4) modulates IL-1β production and key aspects of metabolic remodeling in activated murine macrophages via NO production. Using two complementary genetic models, we reveal that NO modulates levels of the essential TCA cycle metabolites citrate and succinate, as well as the inflammatory mediator itaconate. Furthermore, NO regulates macrophage respiratory function via changes in the abundance of critical N-module subunits in Complex I. However, NO-deficient cells can still upregulate glycolysis despite changes in the abundance of glycolytic intermediates and proteins involved in glucose metabolism. Our findings reveal a fundamental role for
Several recent studies have provided compelling evidence for increased ROS generation in the vascular tissues of SHR.13 22 23 24 For instance, using fluorescence microscopy, Suzuki et al23 have demonstrated enhanced superoxide production in mesenteric arterioles of SHR in vivo. Likewise Grunfeld et al24 have reported increased superoxide generation in cultured aortic endothelial cells from SHR compared with corresponding cells from WKY. Moreover, Cosentino et al13 have shown increased superoxide and hydrogen peroxide release in aortic strips prepared from SHR. ROS are thought to contribute to the generation and/or maintenance of hypertension in SHR by several mechanisms. These include inactivation of endothelium-derived NO,12 14 nonenzymatic generation of vasoconstrictive F2-isoprostanes from arachidonic acid peroxidation,15 and depletion of the NOS cofactor tetrahydrobiopterin.13 The role of oxidative stress in the genesis and maintenance of hypertension in SHR is supported by amelioration of ...
Tetrahydrobiopterin (BH4) is a naturally occurring cofactor essential for critical metabolic pathways. Studies suggest that BH4 supplementation may ameliorate autism symptoms; the biological mechanism for such an effect is unknown. To help understand the relation between central BH4 concentration and systemic metabolism and to develop a biomarker of central BH4 concentration, the relationship between cerebrospinal fluid BH4 concentration and serum amino acids was studied. BH4 concentration was found to be distributed in two groups, a lower and higher BH4 concentration group. Two serum amino acids, citrulline and methionine, differentiated these groups, and the ratio of serum citrulline-to-methionine was found to correlate with the cerebrospinal fluid BH4 concentration (r = -0.67, p
Easy-to-read patient leaflet for Sapropterin Powder for Oral Solution. Includes indications, proper use, special instructions, precautions, and possible side effects.
Tetrahydrobiopterin (BH4) is an essential cofactor for eNOS. Sepiapterin (Sep) is converted into BH4 by the salvage pathway. BH4 is labile at physiological pH and easily oxidized to BH3 or BH2, making it useless as a cofactor for eNOS dependent •NO generation. Loss of BH4, whether through increased oxidation or impaired synthesis, has been linked to pulmonary hypertension. Previously we showed that NADPH oxidase derived superoxide (O2•−) impaired angiogenesis of Pulmonary Artery Endothelial Cells (PAEC) isolated from in utero pulmonary hypertension fetal lambs (HTFL). As increased NADPH oxidase activity has been linked to oxidation of BH4 and in turn, impaired eNOS activity, we hypothesized that restoring BH4 with Sep might improve PAEC function isolated from HTFL. To test this hypothesis we supplemented PAEC isolated from normotensive fetal lambs and HTFL with Sep (30 μM) and then examined its effects on angiogenesis. Angiogenesis was quantified with respect to tube length, cell ...
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What goes inside is as important, support your immune system! CollincGro immunesystem Ecomer alkylglycerol which increase the white bloodcells and supports against several illnesses like flu, bacterials etc. Better skin
Dopamine neurons play a key role in normal and pathological cognitive processes as well as in the effects of certain drugs of addiction. Models of the synapses of such neurons include transporter mechanisms and reaction dynamics. We focus attention on the fundamental reaction which converts tyrosine to DOPA, which involves a cofactor. The Michaelis-Menten formula for the rate of an enzymatic reaction is modified by the presence of cofactors, which may be either essential or non-essential. In the essential case, the reaction rate is found to depend on the relative magnitudes of the concentrations of the primary enzyme and the cofactor. The case of a non-essential cofactor is more complex and it is shown for the first time how this leads to reaction rate formulas which depend explicitly on the concentrations of the enzyme and cofactor. The extended Michaelis-Menten formulas are applied to the above-mentioned reaction with tyrosine hydroxylase as enzyme and biopterin as cofactor. The results are ...
/PRNewswire/ -- BioMarin Pharmaceutical Inc. (NASDAQ: BMRN), today announced that it has entered into a settlement agreement with Par Pharmaceutical that...
GCH1 encodes GTPCH1, the rate-limiting enzyme for BH4 synthesis. Im curious to find out if anyone else has a mutation to this gene because low BH4...
Im 31 weeks and this weekend have started to notice a pattern in BH. I get them from 8-10 every morning and theyre actually pretty painful. I thought I was going to have to call the doc yesterday as they were timeable and not letting up. This is my3rd and I dont remember this with the other 2. Any other ladies experience this?
GTPCH is part of the folate and biopterin biosynthesis pathways. It is responsible for the hydrolysis of guanosine triphosphate ... "Entrez Gene: GCH1 GTP Cyclohydrolase 1 (DOPA-Responsive Dystonia)". Longo N (June 2009). "Disorders of biopterin metabolism". ...
Sepiapterin reductase Longo N (June 2009). "Disorders of biopterin metabolism". Journal of Inherited Metabolic Disease. 32 (3 ...
... deficiency (THBD, BH4D) Biopterin Dihydrobiopterin Pteridine "Sapropterin (Kuvan) Use During Pregnancy". ...
... biopterin and neopterin concentrations". Molecular Genetics and Metabolism. 95 (3): 127-32. doi:10.1016/j.ymgme.2008.07.004. ...
Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin- ...
Sawada M, Hirata Y, Arai H, Iizuka R, Nagatsu T (Mar 1987). "Tyrosine hydroxylase, tryptophan hydroxylase, biopterin, and ...
Abbreviations: DBH: Dopamine β-hydroxylase; AADC: Aromatic L-amino acid decarboxylase; AAAH: (Biopterin-dependent) aromatic ...
... relative importance of the de novo biopterin synthesis versus salvage pathways". The Journal of Biological Chemistry. 284 (41 ...
"Hyperphenylalaninemia with high levels of 7-biopterin is associated with mutations in the PCBD gene encoding the bifunctional ...
Tryptophan hydroxylases catalyze the biopterin-dependent monooxygenation of tryptophan to 5-hydroxytryptophan (5-HTP), which is ...
The molecular formula C9H11N5O3 (molar mass: 237.21 g/mol, exact mass: 237.0862 u) may refer to: Biopterin Dyspropterin ...
... biopterin MeSH D03.438.733.631.202.500 - neopterin MeSH D03.438.733.631.400 - folic acid MeSH D03.438.733.631.400.600 - ...
Folate-biopterin transporter family Frost Bank Tower, Austin, Texas, US Greg Mueller (born 1971), Canadian poker player, ...
... biopterin + 2 NADPH + 2 H+ Thus, the two substrates of this enzyme are 5,6,7,8-tetrahydrobiopterin and NADP+, whereas its 3 ... products are biopterin, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the ...
... net Determination of neopterin and biopterin by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) ...
Family 2.A.71 The Folate-Biopterin Transporter (FBT) Family 2.A.72 The K+ Uptake Permease (KUP) Family 2.A.73 The Short Chain ...
PAH is one of three members of the biopterin-dependent aromatic amino acid hydroxylases, a class of monooxygenase that uses ...
... but neopterin and biopterin were abnormal in only one sibling. The results of this research indicates that when diagnosing the ... quantification of sepiapterin in the CSF is more important and indicative of SR deficiency than using neopterin and biopterin ...
Sometimes a lumbar puncture is performed to measure concentrations of biopterin and neopterin, which can help determine the ... exact form of dopamine-responsive movement disorder: early onset parkinsonism (reduced biopterin and normal neopterin), GTP ...
Tyrosinemia II Argininemia Benign hyperphenylalaninemia Defects of biopterin cofactor biosynthesis Defects of biopterin ...
... compounds found within the body include BH4, the free radical BH3, and BH2 (also a free radical). Biopterin synthesis ... Biopterin synthesis disorders are also a cause of hyperphenylalaninemia; phenylalanine metabolism requires BH4 as a cofactor. ... A number of disorders of biopterin regulation exist. Single-gene defects affecting the gene GCH1 block the first step in ... Mouse gene knockout models that block biopterin synthesis completely die shortly after birth due to their inability to produce ...
The folate-biopterin transporter (FBT) family (TC# 2.A.71) is a distant family within the major facilitator superfamily, most ... As of this edit, this article uses content from "2.A.71 The Folate-Biopterin Transporter (FBT) Family", which is licensed in a ... A related protein in Trypanosoma brucei, ESAGIO, shows weak folate/biopterin transport activity. There are at least 6 ... The probable transport reaction catalyzed by characterized FBT family members is: [folate, biopterin, or AdoMet] (out) + H+ ( ...
... s (AAAH) are a family of aromatic amino acid hydroxylase enzymes which ...
AAAH(英語:Biopterin-dependent aromatic amino acid hydroxylase). AAAH(英語:Biopterin-dependent aromatic amino acid hydroxylase) ...
AAAH(英语:Biopterin-dependent aromatic amino acid hydroxylase). AAAH(英语:Biopterin-dependent aromatic amino acid hydroxylase) ...
Biopterin compounds found within the body include BH4, the free radical BH3, and BH2 (also a free radical). Biopterin synthesis ... Biopterin synthesis disorders are also a cause of hyperphenylalaninemia; phenylalanine metabolism requires BH4 as a cofactor. ... A number of disorders of biopterin regulation exist. Single-gene defects affecting the gene GCH1 block the first step in ... Mouse gene knockout models that block biopterin synthesis completely die shortly after birth due to their inability to produce ...
The folate-biopterin transporter (FBT) family (TC# 2.A.71) is a distant family within the major facilitator superfamily, most ... As of this edit, this article uses content from "2.A.71 The Folate-Biopterin Transporter (FBT) Family", which is licensed in a ... A related protein in Trypanosoma brucei, ESAGIO, shows weak folate/biopterin transport activity. There are at least 6 ... The probable transport reaction catalyzed by characterized FBT family members is: [folate, biopterin, or AdoMet] (out) + H+ ( ...
Biopterin is a coenzyme thats used to make several important neurotransmitters in the body. Problems with biopterin levels can ... Multivitamins can provide biopterin for people whose bodies do not produce enough. Without the right levels of biopterin in the ... One type of coenzyme is called biopterin, a product of the breakdown of the more complex tetrahydrobiopterin, or BH4. Biopterin ... Biopterin is a cofactor in the production of several needed neurotransmitters in the brain. ...
Biopterin gehört, wie die Folate, zur Familie der Pterine. Es ist in seiner biologisch aktiven Form 5,6,7,8-Tetrahydrobiopterin ... Jomaa H. (2019) Biopterin. In: Gressner A.M., Arndt T. (eds) Lexikon der Medizinischen Laboratoriumsdiagnostik. Springer ... Aufgrund der Beteiligung des Biopterin an der NO-Synthasereaktion kommt es bei Entzündungen zu einer Induktion der ... HPLC-basierte Methoden mit fluorimetrischer oder massenspektrometrischer Detektion stehen zur Verfügung, um Biopterin und die ...
biopterin 2-amino-6-[(1R,2R)-1,2- dihydroxypropyl]-1H.... Synonyms: D-Biopterin, Pterin H B2, AG-D-61696, CHEBI:41183, ... Cerebrospinal fluid biogenic amines and biopterin in Rett syndrome [7].. *We measured monoamine metabolites and biopterin in ... Disease relevance of biopterin. *Hyperphenylalaninemia due to a deficiency of biopterin. A variant form of phenylketonuria [1]. ... Chemical compound and disease context of biopterin. *Neopterin and biopterin CSF levels in tardive dyskinesia after clozapine ...
Biopterin, an obligate cofactor of iNOS enzymatic activity, is undetectable in freshly isolated or cultured human monocytes and ... Human mononuclear phagocyte inducible nitric oxide synthase (iNOS): analysis of iNOS mRNA, iNOS protein, biopterin, and nitric ... Human mononuclear phagocyte inducible nitric oxide synthase (iNOS): analysis of iNOS mRNA, iNOS protein, biopterin, and nitric ... Human mononuclear phagocyte inducible nitric oxide synthase (iNOS): analysis of iNOS mRNA, iNOS protein, biopterin, and nitric ...
Biopterin levels were measured in plasma at baseline and after the treatment period, and in saphenous vein (SV) and internal ... Conclusion Although absolute BH4 levels in plasma and SV are increased, chronic oral BH4 therapy does not alter biopterin redox ... B Chronic oral tetrahydrobiopterin treatment in patients with coronary artery disease elevates total biopterin levels but does ... B Chronic oral tetrahydrobiopterin treatment in patients with coronary artery disease elevates total biopterin levels but does ...
B Chronic oral tetrahydrobiopterin treatment in patients with coronary artery disease elevates total biopterin levels but does ... B Chronic oral tetrahydrobiopterin treatment in patients with coronary artery disease elevates total biopterin levels but does ... not improve biopterin redox status or vascular function: a randomised placebo-controlled trial ... not improve biopterin redox status or vascular function: a randomised placebo-controlled trial ...
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biopterin compound. biopterin. compound. Prior art date. 2000-08-31. Application number. IL15453001A. Original Assignee. ... IL154530D0 - Process for production of biopterin compound - Google Patents. Process for production of biopterin compound Info. ... Preparation of L- biopterin JP3137333B2 (en) * 1990-07-21. 2001-02-19. サントリー株式会社. Preparation of tetrahydrobiopterin and enzyme ... Process for production of biopterin compound IL154530A IL154530A (en) 2000-08-31. 2003-02-18. Process for the production of a ...
... biopterin, and histamine pathways.. What is StrateGene?. StrateGene is a genetic reporting tool that uses AncestryDNA (Version ...
Neopterin and Biopterin are by products of the redox reactions involving tetrahydrobiopterin (BH4). BH4 functions as a cofactor ... Low biopterin levels may reflect insufficient BH4 status.. • Urine Test: Collection is a First Morning Void (FMV) Neopterin is ... Neopterin and Biopterin are by products of the redox reactions involving tetrahydrobiopterin (BH4). BH4 functions as a cofactor ...
Biopterin compounds found within the body include both BH4 and BH2.. Synthesis. Biopterin synthesis occurs through two ... ビオプテリン(biopterin)は、体内で合成される補酵素の一つ。テトラヒドロビオプテリンの酸化分解産物である。 専門用語集 の検索結果 家庭の医学の検索結果 … 1件 ビオプテリン異常症 「ビオプテリン」の使用例を検索する "Lets get up ... チロシン tyrosine (フェニル基の3位にOHを導入) :律速酵素 -チロシン 3-モノオキシゲナーゼ tyrosine 3-monooxygenase, チロシン水酸化
"Biopterin" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical Subject ... This graph shows the total number of publications written about "Biopterin" by people in this website by year, and whether " ... Below are the most recent publications written about "Biopterin" by people in Profiles. ...
Biopterin dynamics and effects of BH4 on blood glucose levels in diabetic mice. A-D: BH2 levels and BH4-to-BH2 ratio of liver, ... Biopterin dynamics and effects of BH4 on blood glucose levels in diabetic mice.. In STZ diabetic wild-type mice, the content of ... Biopterin analysis.. Tissues or whole blood of wild-type mice and wild-type mice with STZ-induced diabetes was collected. For ... The organs were weighed, frozen immediately in liquid N2, and then stored at −80°C. Total biopterin, BH4, and BH2 were measured ...
... hyperphenylalaninaemia due to inhibition of phenylalanine hydroxylase by tetrahydro-7-biopterin. * Home ... hyperphenylalaninaemia due to inhibition of phenylalanine hydroxylase by tetrahydro-7-biopterin. Publikationstyp:. ... hyperphenylalaninaemia due to inhibition of phenylalanine hydroxylase by tetrahydro-7-biopterin. In: Journal of inherited ... hyperphenylalaninaemia due to inhibition of phenylalanine hydroxylase by tetrahydro-7-biopterin,/dcterms:title, ,dc:contributor ...
Defects of Biopterin Cofactor Biosynthesis / Biopterin Cofactor Regeneration. December 1, 2016. An inherited disorder of co- ...
Biopterin LKT Labs. Biopterin is an endogenous pterin coenzyme that acts as a cofactor for amino acid hydroxylases that produce ...
... biopterin; c-reactive protein; camitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; ...
... biopterin; c-reactive protein; carnitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; ...
Measurements of Biopterin. Measurements of biopterin content were performed using high-performance liquid chromatography (HPLC ... Analysis of reduced forms of biopterin in biological tissues and fluids. Anal Biochem. 1980; 102: 176-188. ... had no effect on the increase in H4B caused by shear and had no effect on the ratio of reduced to oxidized biopterin (Figure 5C ... Diagnosis of dopa-responsive dystonia and other tetrahydrobiopterin disorders by the study of biopterin metabolism in ...
Jeannette Vasquez Vivar, PhD, is a professor in the Department of Biophysics and associate director of the Redox Biology Program.
... biopterin; c-reactive protein; carnitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; ...
... and biopterin (p , 0.01) in the experimental piglets. Changes in cortisol concentrations and leukocyte counts were influenced ... Pterins (neopterin and biopterin) in the piglets blood serum were analyzed by separation using reversed-phase HPLC. A single ... Keywords: iron; neopterin; biopterin; cortisol; leukogram iron; neopterin; biopterin; cortisol; leukogram This is an open ... Pterins (neopterin and biopterin) in the piglets blood serum were analyzed by separation using reversed-phase HPLC. A single ...
... biopterin; c-reactive protein; camitine; camosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; ...
Biopterin defect in cofactor biosynthesis Biopterin defect in cofactor regeneration Tyrosinemia, type II ...
Biopterin Levels, Schizophrenia and Schizoaffective Disorder.. Posted on June 28, 2007. by Dr. Gary Pack ... Miscellaneous: Amines, Biopterin, Brain, Catecholamines, Conduction, Dopamine, l-DOPA, Neurotransmitters, Nitric oxide (NO), ...
3. Biopterin and Related Derivatives. 4. Pteridines Related to Riboflavin. References. Chapter VIII. Vitamin B12. 1. ...
We found that biopterin contents in the brains of these knock-out mice were moderately decreased from postnatal day 0 (P0) and ... We found that biopterin contents in the brains of these knock-out mice were moderately decreased from postnatal day 0 (P0) and ... Homma, D, Sumi-Ichinose, C, Tokuoka, H, Ikemoto, K, Nomura, T, Kondo, K, Katoh, S & Ichinose, H 2011, Partial biopterin ... We found that biopterin contents in the brains of these knock-out mice were moderately decreased from postnatal day 0 (P0) and ...
  • The folate-biopterin transporter (FBT) family (TC# 2.A.71) is a distant family within the major facilitator superfamily, most closely related to drug resistance permeases. (wikipedia.org)
  • As of this edit, this article uses content from "2.A.71 The Folate-Biopterin Transporter (FBT) Family", which is licensed in a way that permits reuse under the Creative Commons Attribution-ShareAlike 3.0 Unported License, but not under the GFDL. (wikipedia.org)
  • Leishmania infantum JPCM5 putative folate/biopterin transporter (FT1), partial mRNA. (genscript.com)
  • 2010). High affinity S-Adenosylmethionine plasma membrane transporter of Leishmania is a member of the folate biopterin transporter (FBT) family. (tcdb.org)
  • CS1 maint: discouraged parameter (link) CS1 maint: archived copy as title (link) Neurological aspects of biopterin metabolism WiseGeek. (wikipedia.org)
  • Longo N. Disorders of biopterin metabolism. (medlineplus.gov)
  • Nitric oxide synthesis also uses biopterin derivatives as cofactors. (wikipedia.org)
  • Biopterin s are pterin derivatives which function as endogenous enzyme cofactors in many species of animals and in some bacteria and fungi. (meddic.jp)
  • Neopterin and Biopterin are by products of the redox reactions involving tetrahydrobiopterin (BH4). (holisticheal.com)
  • Pterins (neopterin and biopterin) in the piglets' blood serum were analyzed by separation using reversed-phase HPLC. (mdpi.com)
  • The document Neopterin and Biopterin provides a good technical overview of the production, use, and recycling of BH4. (snpedia.com)
  • One type of coenzyme is called biopterin, a product of the breakdown of the more complex tetrahydrobiopterin, or BH4. (wisegeek.com)
  • Without the right levels of biopterin in the bloodstream, along with its cofactor dihydrobiopterin, the body could develop some serious medical conditions, including one with symptoms similar to phenylketonuria . (wisegeek.com)
  • Profound biopterin oxidation and protein tyrosine nitration in tissues of ApoE-null mice on an atherogenic diet: contribution of inducible nitric oxide synthase. (ox.ac.uk)
  • Effect of ultraviolet-A (UV-A) light on growth, photosynthetic activity and production of biopterin glucoside by the marine UV-A resistant cyanobacterium Oscillatoria sp. (elsevier.com)
  • Fingerprint Dive into the research topics of 'Effect of ultraviolet-A (UV-A) light on growth, photosynthetic activity and production of biopterin glucoside by the marine UV-A resistant cyanobacterium Oscillatoria sp. (elsevier.com)
  • A related protein in Trypanosoma brucei, ESAGIO, shows weak folate/biopterin transport activity. (wikipedia.org)
  • Our results demonstrate a critical role of biopterin in the augmentation of TH protein in the postnatal period. (fujita-hu.ac.jp)
  • This gene encodes a member of the biopterin-dependent aromatic amino acid hydroxylase protein family. (genecards.org)
  • However, total biopterin represents the sum of BH 4 , 7,8-dihydrobipterin (BH 2 ), and fully oxidized biopterin, and one cannot exclude possible the effect of either reduced BH 4 or increased BH 2 concentrations on the endothelial dysfunction in these patients. (ahajournals.org)
  • GCH1 haplotype determines vascular and plasma biopterin availability in coronary artery disease effects on vascular superoxide production and endot. (cdc.gov)
  • GCH1 haplotype determines vascular and plasma biopterin availability in coronary artery disease effects on vascular superoxide production and endothelial function. (cdc.gov)
  • This is an interesting finding because both in serum and urine from patients with coronary artery diseases and hypercholesterolemia, total plasma biopterin concentrations were found to be unchanged 2 (unpublished data, 2002). (ahajournals.org)
  • A number of disorders of biopterin regulation exist. (wikipedia.org)
  • Biopterin compounds found within the body include BH4, the free radical BH3, and BH2 (also a free radical). (wikipedia.org)
  • Biopterin compounds found within the body include both BH4 and BH2. (meddic.jp)
  • Functionally characterized members of the family include FT1, the major folate transporter, and BT1, the biopterin/folate transporter and AdoMetT1, the major S-adenosylmethionine uptake porter. (wikipedia.org)
  • Biopterin" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (wakehealth.edu)
  • On the mechanism of action of folate- and biopterin-requiring enzymes. (ebi.ac.uk)
  • Scientists analyze blood to calculate levels of biopterin in relation to other enzyme levels to determine if it or some other deficiency is responsible for a patient's symptoms. (wisegeek.com)
  • Conclusion Although absolute BH4 levels in plasma and SV are increased, chronic oral BH4 therapy does not alter biopterin redox status (BH4:BH2 ratio) in either plasma or vascular tissue. (bmj.com)
  • The probable transport reaction catalyzed by characterized FBT family members is: [folate, biopterin, or AdoMet] (out) + H+ (out) → [folate, biopterin, or AdoMet] (in) + H+ (in) The FBT family includes functionally characterized members from protozoa, cyanobacteria and plants. (wikipedia.org)
  • Single-gene defects affecting the gene GCH1 block the first step in biopterin synthesis, and lead to dopamine-responsive dystonia, also known as Segawa's syndrome. (wikipedia.org)
  • Biopterin is a cofactor in the production of several needed neurotransmitters in the body, including dopamine , serotonin and epinepherine. (wisegeek.com)
  • Differential oxidation with iodine and subsequent high-pressure liquid chromatography (HPLC), according to Fukushima and Nixon, 3 is a simple method to measure different oxidation forms of biopterin. (ahajournals.org)
  • Belongs to the biopterin-dependent aromatic amino acid hydroxylase family. (abcam.com)
  • A pteridine that is a metabolite of guanine triphosphate (GTP) and a precursor for biopterin. (semanticscholar.org)
  • We examined the associations between haplotypes of the GCH1 gene, GCH1 expression and biopterin levels, and the effects on endothelial function and vascular superoxide production. (cdc.gov)
  • Mouse gene knockout models that block biopterin synthesis completely die shortly after birth due to their inability to produce catecholamines and neurotransmitters. (wikipedia.org)
  • Biopterin is a cofactor in the production of several needed neurotransmitters in the brain. (wisegeek.com)
  • HPLC-basierte Methoden mit fluorimetrischer oder massenspektrometrischer Detektion stehen zur Verfügung, um Biopterin und die reduzierten Derivate BH2 und BH4 zu bestimmen. (springer.com)
  • Detection of biopterin glucoside levels in irradiated cells by HPLC demonstrated that after 10 h there was a rapid increase in biopterin glucoside content. (elsevier.com)
  • HPLC separation of biopterin from pterin and isoxanthopterin is essential for the correct interpretation. (ahajournals.org)
  • If the Biopterin is not available for the AAAH enzyme, phenylalanine builds up. (autismcoach.com)
  • With StrateGene you can quickly learn about potential issues by overlaying your SNPs or those of your patients onto the Pathway Planners covering the important folate, methionine, transsulfuration, biopterin, and histamine pathways. (seekinghealth.com)
  • Biopterin Levels, Schizophrenia and Schizoaffective Disorder. (rainbow.coop)
  • Low biopterin levels are suspected contributors to Alzheimer's and Parkinson's disease. (wisegeek.com)
  • Low biopterin levels may lead to clinical depression. (wisegeek.com)
  • Biopterin levels were measured in plasma at baseline and after the treatment period, and in saphenous vein (SV) and internal mammary artery (IMA) tissue collected at the time of surgery. (bmj.com)
  • Low biopterin levels may reflect insufficient BH4 status. (holisticheal.com)
  • In response to UV-A irradiation this cyanobacterium produces high levels of a UV-A absorbing compound which was identified previously as biopterin glucoside. (elsevier.com)
  • The difference in biopterin content between the two oxidations represents the actual BH 4 levels. (ahajournals.org)
  • We found that biopterin contents in the brains of these knock-out mice were moderately decreased from postnatal day 0 (P0) and remained constant up to P21. (fujita-hu.ac.jp)
  • Quinone-dihydrobiopterin can also degrade to biopterin. (snpedia.com)
  • Studies show success, in many cases, with mere multivitamins or niacin- and iron-rich diets that provide the extra biopterin needed by people whose bodies do not produce enough. (wisegeek.com)
  • the de novo pathway involves three enzymatic steps and proceeds from GTP, while the salvage pathway converts sepiapterin to biopterin. (wikipedia.org)
  • Biopterin, an obligate cofactor of iNOS enzymatic activity, is undetectable in freshly isolated or cultured human monocytes and peritoneal macrophages. (bloodjournal.org)