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Abstract
The pteridine tetrahydrobiopterin (BH4) is an essential cofactor in the biosynthesis of dopamine, (nor)epinephrine, serotonin and nitric oxide (NO). Furthermore, BH4 has a direct influence on release mechanisms of these neurotransmitters and on serotonin receptor binding activity immunology. The synthesis of BH4 is stimulated by interferon-gamma and hence there is a close relationship with the immune system HPA-axis. In animal experiments it was also found that the hypothalamus-pituitary-adrenal axis influences the pteridine metabolism. In clinical studies, so far, no evidence has been found for this relationship diseases. A congenital biopterin deficiency results in atypical phenylketonuria with severe neuropsychiatric symptoms. In several neurological diseases, such as Parkinson's disease, decreased levels of BH4 are found depression. Since 1984 there have been reports on decreased biopterin and increased neopterin levels in urine and plasma of depressed patients. Conflicting results have also been found, however, due probably to methodological problems therapy. Until now, oral administration of BH4 to depressed patients has been performed by two investigators, which resulted in mainly temporal clinical improvement discussion. Understanding of biochemical mechanisms in which pteridines are involved may contribute to our knowledge of the pathogenesis and treatment of affective disorders. This paper aims to provide an overview of the relevant literature and warrant for further research on this intriguing compound.
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Affiliation(s)
- R Hoekstra
- 1Delta Psychiatric Hospital, MFC-Zuid, Rotterdam
| | - D Fekkes
- 2Department of Psychiatry, Section Pathophysiology of Behavior, Erasmus University, Rotterdam, the Netherlands
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2
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Vrecko K, Storga D, Birkmayer JG, Möller R, Tafeit E, Horejsi R, Reibnegger G. NADH stimulates endogenous dopamine biosynthesis by enhancing the recycling of tetrahydrobiopterin in rat phaeochromocytoma cells. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1361:59-65. [PMID: 9247090 DOI: 10.1016/s0925-4439(97)00016-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Treatment of Parkinson patients with L-DOPA (3,4-dihydroxy-L-phenylalanine) leads to endproduct inhibition of tyrosine hydroxylase, the key enzyme in dopamine biosynthesis and the enzyme needing tetrahydrobiopterin and iron as cofactors. To overcome this problem an alternative treatment was investigated which attempted to stimulate endogenous dopamine biosynthesis. Incubation of rat PC 12 cells with NADH (beta-nicotinamide adeninedinucleotide) leads to increased dopamine production. We investigated the possibility that this increase of dopamine biosynthesis was due to stimulation of quinonoid dihydropteridine reductase, the enzyme which recycles the inactive dihydrobiopterin to the active tetrahydrobiopterin. The experiments showed that whereas NADH is able to increase dopamine production in PC 12 cells (rat phaeochromocytoma cells, clone PC 12) up to three-fold, no influence is exerted by NADH on pteridine metabolism; neither are tetrahydrobiopterin concentrations nor the de novo-biosynthesis of pteridines from guanosine triphosphate altered by NADH. Further no influence of NADH on protein de novo synthesis of quinonoid dihydropteridine reductase was observed. However, NADH was able to directly increase the catalytic activity of this enzyme. Our results suggest that the stimulation of dopamine biosynthesis by NADH is due to more rapid regeneration of quinonoid dihydrobiopterin to tetrahydrobiopterin.
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Affiliation(s)
- K Vrecko
- Institute for Medical Chemistry and Pregl Laboratory, KF University of Graz, Austria
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3
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Anastasiadis PZ, Kuhn DM, Blitz J, Imerman BA, Louie MC, Levine RA. Regulation of tyrosine hydroxylase and tetrahydrobiopterin biosynthetic enzymes in PC12 cells by NGF, EGF and IFN-gamma. Brain Res 1996; 713:125-33. [PMID: 8724983 DOI: 10.1016/0006-8993(95)01494-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The regulation of catecholamine and tetrahydrobiopterin synthesis was investigated in cultured rat pheochromocytoma PC12 cells following treatments with nerve growth factor (NGF), epidermal growth factor (EGF) and interferon-gamma (IFN-gamma). NGF and EGF, but not IFN-gamma, caused an increase after 24 h in the levels of BH4 and catecholamines, and the activities of tyrosine hydroxylase and GTP cyclohydrolase, the rate-limiting enzymes in catecholamine and BH4 synthesis, respectively. Actinomycin D, a transcriptional inhibitor, blocked treatment-induced elevations in tyrosine hydroxylase and GTP cyclohydrolase activities. NGF, EGF or IFN-gamma did not affect the activity of sepiapterin reductase, the final enzyme in BH4 biosynthesis. Rp-cAMP, an inhibitor of cAMP-mediated responses, blocked the induction of tyrosine hydroxylase by NGF or EGF; inhibition of protein kinase C partially blocked the EGF effect, but not the NGF effect, NGF also induced GTP cyclohydrolase in a cAMP-dependent manner, while the EGF effect was not blocked by Rp-cAMP or protein kinase C inhibitors. Sphingosine induced GTP cyclohydrolase in a protein kinase C-independent manner without affecting tyrosine hydroxylase activity. Our results suggest that both tyrosine hydroxylase and GTP cyclohydrolase are induced in a coordinate and transcription-dependent manner by NGF and EGF, while conditions exist where the induction of tyrosine hydroxylase and GTP cyclohydrolase is not coordinately regulated.
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Affiliation(s)
- P Z Anastasiadis
- William T. Gossett Neurology Laboratories, Henry Ford Health Sciences Center, Detroit, MI 48202, USA
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4
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Abou-Saleh MT, Anderson DN, Collins J, Hughes K, Cattell RJ, Hamon CG, Blair JA. The role of pterins in depression and the effects of antidepressive therapy. Biol Psychiatry 1995; 38:458-63. [PMID: 8672606 DOI: 10.1016/0006-3223(94)00323-u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Urinary excretion of neopterins (N) and biopterins (B) was measured in 48 patients with depression before and after treatment with placebo, antidepressants, or electroconvulsive therapy (ECT), and in 26 healthy control subjects. Patients prior to and after treatment had a significantly greater neopterin/biopterin (N:B) ratio than control subjects. There was a significant correlation between N:B ratios and the severity of depression and plasma cortisol. As a raised N:B ratio implies failure to convert neopterin to biopterin, it is possible that reduced availability of tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, serotonin and dopamine, may exert rate-limiting control over the synthesis of monoamines implicated in the pathogenesis of depressive illness.
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Affiliation(s)
- M T Abou-Saleh
- Department of Psychiatry and Behavioural Sciences, United Arab Emirates University, Al Ain, UAE
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5
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Anastasiadis PZ, Kuhn DM, Levine RA. Tetrahydrobiopterin uptake into rat brain synaptosomes, cultured PC12 cells, and rat striatum. Brain Res 1994; 665:77-84. [PMID: 7882022 DOI: 10.1016/0006-8993(94)91154-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The uptake of (6R)-5,6,7,8-tetrahydro-L-biopterin (BH4) was investigated in rat brain synaptosomes, cultured rat pheochromocytoma (PC12) cells, and rat striatum (control and depleted of dopamine neurons) following peripheral administration. A linear, non-saturable, concentration-dependent intracellular accumulation was observed when BH4 was added to either synaptosomes or PC12 cells. The uptake of BH4, in contrast to that of serotonin uptake into synaptosomes or norepinephrine (NE) uptake into PC12 cells, was not dependent on glucose or extracellular sodium. Stimulation of tryptophan hydroxylation in synaptosomes by incubation with 5 microM tryptophan (which increases utilization of BH4 in serotonergic cells) did not alter BH4 uptake. In rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of dopamine neurons, BH4 uptake was the same in control and lesioned striatum following peripheral administration. These results indicate that neurons and PC12 cells do not appear to have a specific membrane carrier for BH4 and that BH4 uptake into cells is due to passive diffusion.
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Affiliation(s)
- P Z Anastasiadis
- William T. Gossett Neurology Laboratories, Henry Ford Hospital, Detroit, MI 48207
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Anderson DN, Wilkinson AM, Abou-Saleh MT, Blair JA. Recovery from depression after electroconvulsive therapy is accompanied by evidence of increased tetrahydrobiopterin-dependent hydroxylation. Acta Psychiatr Scand 1994; 90:10-3. [PMID: 7976441 DOI: 10.1111/j.1600-0447.1994.tb01547.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Serum phenylalanine and tyrosine levels were measured in 26 patients with severe depression before and after receiving electroconvulsive therapy. The phenylalanine:tyrosine [P:T] ratio declined significantly for those responding to treatment but not for nonresponders. These findings are discussed in relation to tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, dopamine and serotonin and the hydroxylation of phenylalanine to tyrosine.
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Affiliation(s)
- D N Anderson
- Sir Douglas Crawford Unit, Mossley Hill Hospital, Liverpool, United Kingdom
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Fleischhacker WW, Levine RA, Lieberman JA, Pollack S, Johns CA, Richardson MA. Neopterin and biopterin CSF levels in tardive dyskinesia after clozapine treatment. Biol Psychiatry 1993; 34:741-5. [PMID: 8292676 DOI: 10.1016/0006-3223(93)90046-g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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8
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Tani Y, Ohno T. Analysis of 6R- and 6S-tetrahydrobiopterin and other pterins by reversed-phase ion-pair liquid-chromatography with fluorimetric detection by post-column sodium nitrite oxidation. JOURNAL OF CHROMATOGRAPHY 1993; 617:249-55. [PMID: 8408390 DOI: 10.1016/0378-4347(93)80495-p] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A rapid and sensitive reversed-phase ion-pair liquid chromatographic system with fluorimetric detection by post-column sodium nitrite oxidation was established for measuring six pterin compounds (6R-5,6,7,8-tetrahydrobiopterin, 6S,5,6,7,8-tetrahydrobiopterin, 7,8-dihydrobiopterin, biopterin, pterin and D-neopterin). The coefficients of variation for these pterins were 0.705-3.714%, and the minimum detectable amount was ca. 10-20 pg at a signal-to-noise ratio of 3. A linear detector response was also verified. The concentrations of the pterin compounds in rat tissues were measured by the described method. Furthermore, by means of brain microdialysis, the output of pterin compounds from rat striatum was detected. Therefore, these results demonstrate that this system can be applied to analyses not only of various rat tissues but also of dialysates collected in vivo.
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Affiliation(s)
- Y Tani
- Suntory Institute for Biomedical Research, Osaka, Japan
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9
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Hossain MA, Masserano JM, Weiner N. Effects of electroconvulsive shock on tetrahydrobiopterin and GTP-cyclohydrolase activity in the brain and adrenal gland of the rat. J Neurochem 1992; 59:2237-43. [PMID: 1431904 DOI: 10.1111/j.1471-4159.1992.tb10116.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of a single and repeated electroconvulsive shock (ECS) (300 mA, 0.2 s) on tetrahydrobiopterin (BH4) levels and GTP-cyclohydrolase activity in the brain and adrenal glands of rats were examined. Twenty-four hours after the last ECS treatment (one/day for 7 days), biopterin levels were significantly elevated in the locus coeruleus, hippocampus, frontal cortex, hypothalamus, ventral tegmental area, and adrenal gland. There were no changes in biopterin levels after a single application of ECS. GTP-cyclohydrolase activity was significantly increased in the locus coeruleus, frontal cortex, hippocampus, hypothalamus, and adrenal gland 24 h after repeated ECS and remained elevated in certain tissues up to 8 days after the last treatment. Kinetic analysis of adrenal and locus coeruleus GTP-cyclohydrolase 1 day after 7 days of ECS showed significant changes in both Km and Vmax values. These data suggest that the long-term increases in BH4 levels and GTP-cyclohydrolase activity after repeated ECS may play a part in the mediation of the antidepressant effects of ECS.
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Affiliation(s)
- M A Hossain
- University of Colorado Health Sciences Center, Department of Pharmacology, Denver 80262
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Anderson DN, Abou-Saleh MT, Collins J, Hughes K, Cattell RJ, Hamon CG, Blair JA, Dewey ME. Pterin metabolism in depression: an extension of the amine hypothesis and possible marker of response to ECT. Psychol Med 1992; 22:863-869. [PMID: 1488484 DOI: 10.1017/s0033291700038435] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Urinary excretion of neopterins and biopterins was measured in 23 patients with severe depression before and after receiving electroconvulsive therapy (ECT) and 26 healthy control subjects. Patients with psychotic depression and those responding to ECT had neopterin:biopterin (N:B) ratio significantly higher than controls before commencing ECT and positive therapeutic response was associated with reduction of N:B ratio towards control values. As a raised N:B ratio implies failure to convert neopterin to biopterin it is possible that reduced availability of tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, serotonin and dopamine, may exert rate limiting control over the synthesis of monoamines implicated in the pathogenesis of depressive disorders. The N:B ratio may be a marker for certain depressive subtypes and response to ECT.
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Affiliation(s)
- D N Anderson
- Department of Psychiatry, Fazakerley Hospital, Liverpool
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11
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Eto I, Bandy MD, Butterworth CE. Plasma and urinary levels of biopterin, neopterin, and related pterins and plasma levels of folate in infantile autism. J Autism Dev Disord 1992; 22:295-308. [PMID: 1624410 DOI: 10.1007/bf01058157] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tetrahydrobiopterin is essential for brain cells to make monoamine neurotransmitters. It has been reported that the concentrations of tetrahydrobiopterin in plasma and urine are low in certain mental disorders and that oral supplements are beneficial. A group of Japanese investigators have been conducting clinical trials of the effect of administration of tetrahydrobiopterin to autistic children and reported that it is beneficial with no significant side effects. We, therefore, initiated a study to assess plasma and urinary levels of tetrahydrobiopterin in infantile autism to see if they are reduced. Besides tetrahydrobiopterin, we also determined plasma and urinary levels of neopterin and monapterin in these individuals in order to evaluate the status of dihydroneopterin triphosphate, a key biosynthetic precursor of tetrahydrobiopterin. Sixteen autistic children and 12 healthy controls were included in this study. Results indicated that the plasma and urinary levels of tetrahydrobiopterin are not statistically different between the two groups and, therefore, no simple explanation for the beneficial effects of administration of tetrahydrobiopterin on autistic children can be offered at the present time. In contrast, plasma and urinary levels of neopterin were depressed (.01 less than p less than .05) and plasma monapterin was also significantly depressed (p less than .01) in autistic subjects compared with controls. Levels of other pterins, including folate, were not statistically different between the two groups. The basis for this depression in neopterin and monapterin is unknown. It does not seem likely that this depression could be attributed to a difference in age or T-lymphocyte/macrophage activity. However, further studies are needed to investigate these possibilities.
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Affiliation(s)
- I Eto
- Department of Nutrition Sciences, University of Alabama, Birmingham 35294
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12
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Reversal of α-Methyltyrosine-Induced Hypoactivity by 6-(R)-5,6,7,8-Tetrahydro-L-Erythrobiopterin (R-THBP) in Mice. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/s0021-5198(19)39779-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Hashimoto R, Ozaki N, Ohta T, Kasahara Y, Kaneda N, Nagatsu T. The plasma tetrahydrobiopterin levels in patients with affective disorders. Biol Psychiatry 1990; 28:526-8. [PMID: 2223922 DOI: 10.1016/0006-3223(90)90487-m] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- R Hashimoto
- Department of Psychiatry, Nagoya University School of Medicine, Japan
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14
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Zigmond MJ, Stricker EM. Animal models of parkinsonism using selective neurotoxins: clinical and basic implications. INTERNATIONAL REVIEW OF NEUROBIOLOGY 1989; 31:1-79. [PMID: 2689379 DOI: 10.1016/s0074-7742(08)60277-9] [Citation(s) in RCA: 154] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M J Zigmond
- Department of Behavioral Neuroscience, University of Pittsburgh, Pennsylvania 15260
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Suzuki S, Watanabe Y, Tsubokura S, Kagamiyama H, Hayaishi O. Decrease in tetrahydrobiopterin content and neurotransmitter amine biosynthesis in rat brain by an inhibitor of guanosine triphosphate cyclohydrolase. Brain Res 1988; 446:1-10. [PMID: 2453255 DOI: 10.1016/0006-8993(88)91290-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To investigate the regulatory role of tetrahydrobiopterin in neurotransmitter amine biosynthesis, 2,4-diamino-6-hydroxypyrimidine, a potent inhibitor of guanosine triphosphate cyclohydrolase which is a rate-limiting enzyme of tetrahydrobiopterin biosynthesis, was administered intraperitoneally to weanling rats. Four h after 4 injections at 4-h intervals, the biopterin contents in plasma and liver were reduced to the level of 9 and 3.5%, respectively, of those in the control group injected with saline; while the contents in the whole brain, neocortex + striatum, diencephalon, and brainstem were 34, 50, 33 and 28%, respectively, of the control level. When in vivo tyrosine and tryptophan hydroxylase activities were measured over a 30-min period after the inhibition of aromatic amino acid decarboxylase, the accumulation of dihydroxyphenylalanine was reduced to 74, 77, 67 and 69% of the control in the whole brain, neocortex + striatum, diencephalon, and brainstem, respectively; and the accumulation of 5-hydroxytryptophan, to 71, 74, 66 and 65% of the control, respectively. On the other hand, 5-hydroxytryptamine and 5-hydroxyindole acetic acid contents were not altered in any brain regions, although norepinephrine and dopamine contents were reduced to approximately 70% of the control in the brainstem and the contents of dopamine metabolites were significantly decreased in the diencephalon and brainstem. Plasma phenylalanine level was significantly elevated, while the plasma tyrosine level was reduced, compared with the control level of these amino acids. These results indicate that the drug-treated rats could be an animal model for tetrahydrobiopterin-deficient disease involving neurological disorder.
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Affiliation(s)
- S Suzuki
- Department of Medical Chemistry, Osaka Medical College, Japan
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16
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Ziegler I. [Pterins: pigments, cofactors and signal connections in cell interactions]. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 1987; 74:563-72. [PMID: 3327013 DOI: 10.1007/bf00368513] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Pteridines were originally described as pigments of insects and lower vertebrates. The electron-donating function of tetrahydrobiopterin for aromatic amino acid hydroxylation and thus, for neurotransmitter biosynthesis adduced the participation of unconjugated pterins in cellular metabolism. There has been increasing evidence moreover that they are signal molecules for intercellular recognition in primitive eucaryotes, as well as modifiers of signal polypeptides in higher vertebrates.
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Affiliation(s)
- I Ziegler
- Gesellschaft für Strahlen- und Umweltforschung, Institut für Experimentelle Hämatologie, München
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Olgiati VR, Algeri S, Stramentinoli G. Biochemical and behavioural indices of striatal dopaminergic activity after 6-methyltetrahydropterin. PHARMACOLOGICAL RESEARCH COMMUNICATIONS 1987; 19:231-40. [PMID: 3602044 DOI: 10.1016/0031-6989(87)90066-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The biochemical effects of 6-methyltetrahydropterin (6-MPH4), a synthetic analogue of tetrahydrobiopterin (BH4), the hydroxylase cofactor, were investigated on striatal dopaminergic neurons in the rat. Although a single parenteral dose of 6-MPH4 (18 or 54 mg/kg) did not significantly increase the content of dopamine (DA) or its acidic metabolites, L-didrohyphenylanine (L-DOPA) accumulation after decarboxylase inhibition was evident in rats receiving 54 mg/kg of 6-MPH4. On the other hand, 6-MPH4 (18 mg/kg) potentiated the reserpine-induced DA metabolism as demonstrated by increased HVA levels. In a behavioural test, 6-MPH4 partially prevented haloperidol-induced catalepsy. BH4 concentrations could thus be subsaturating with respect to tyrosine hydroxylase (TH), particularly when the enzyme activity is stimulated and the results suggest that cofactor supply may have pharmacological significance.
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Abstract
A model for tetrahydrobiopterin deficiency in mice is described. Elevated levels of phenylalanine produced in the model were shown to be dramatically reduced after injection of tetrahydrobiopterin. A comparison of several reduced pterins for their efficacy in the system is described. The unnatural S isomer of tetrahydrobiopterin was shown to be active in the system.
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Curtius HC, Heintel D, Ghisla S, Kuster T, Leimbacher W, Niederwieser A. Tetrahydrobiopterin biosynthesis. Studies with specifically labeled (2H)NAD(P)H and 2H2O and of the enzymes involved. EUROPEAN JOURNAL OF BIOCHEMISTRY 1985; 148:413-9. [PMID: 3888618 DOI: 10.1111/j.1432-1033.1985.tb08855.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The biosynthesis of tetrahydrobiopterin from either dihydroneopterin triphosphate, sepiapterin, dihydrosepiapterin or dihydrobiopterin was investigated using extracts from human liver, dihydrofolate reductase and purified sepiapterin reductase from human liver and rat erythrocytes. The incorporation of hydrogen in tetrahydrobiopterin was studied in either 2H2O or in H2O using unlabeled NAD(P)H or (R)-(4-2H)NAD(P)H or (S)-(4-2H)NAD(P)H. Dihydrofolate reductase catalyzed the transfer of the pro-R hydrogen of NAD(P)H during the reduction of 7,8-dihydrobiopterin to tetrahydrobiopterin. Sepiapterin reductase catalyzed the transfer of the pro-S hydrogen of NADPH during the reduction of sepiapterin to 7,8-dihydrobiopterin. In the presence of partially purified human liver extracts one hydrogen from the solvent is introduced at position C(6) and the 4-pro-S hydrogen from NADPH is incorporated at each of the C(1') and C(2') position of BH4. Label from the solvent is also introduced into position C(3'). These results suggest that dihydrofolate reductase is not involved in the biosynthesis of tetrahydrobiopterin from dihydroneopterin triphosphate. They are consistent with the assumption of the occurrence of a 6-pyruvoyl-tetrahydropterin intermediate, which is proposed to be formed upon triphosphate elimination from dihyroneopterin triphosphate, and via an intramolecular redox reaction. Our results suggest that the reduction of 6-pyruvoyl-tetrahydropterin might be catalyzed by sepiapterin reductase.
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Curtius HC, Heintel D, Ghisla S, Kuster T, Leimbacher W, Niederwieser A. Biosynthesis of tetrahydrobiopterin in man. J Inherit Metab Dis 1985; 8 Suppl 1:28-33. [PMID: 3930838 DOI: 10.1007/bf01800656] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The biosynthesis of tetrahydrobiopterin (BH4) from dihydroneopterin triphosphate (NH2P3) was studied in human liver extract. The phosphate-eliminating enzyme (PEE) was purified approximately 750-fold. The conversion of NH2P3 to BH4 was catalyzed by this enzyme in the presence of partially purified sepiapterin reductase. Mg2+ and NADPH. The PEE is heat stable when heated at 80 degrees C for 5 min. It has a molecular weight of 63 000 daltons. One possible intermediate 6-(1'-hydroxy-2'-oxopropyl)5,6,7,8-tetrahydropterin(2'-oxo-tetrahydropte rin) was formed upon incubation of BH4 in the presence of sepiapterin reductase and NADP+ at pH 9.0. Reduction of this compound with NaBD4 yielded monodeutero threo and erythro-BH4, the deuterium was incorporated at the 2' position. This and the UV spectra were consistent with a 2'-oxo-tetrahydropterin structure. Dihydrofolate reductase (DHFR) catalyzed the reduction of BH2 to BH4 and was found to be specific for the pro-R-NADPH side. The sepiapterin reductase catalyzed the transfer of the pro-S hydrogen of NADPH during the reduction of sepiapterin to BH2. In the presence of crude liver extracts the conversion of NH2P3 to BH4 requires NADPH. Two deuterium atoms were incorporated from (4S-2H)NADHP in the 1' and 2' position of the BH4 side chain. Incorporation of one hydrogen from the solvent was found at position C(6). These results are consistent with the occurrence of an intramolecular redox exchange between the pteridine nucleus and the side chain and formation of 6-pyruvoyl-5,6,7,8-tetrahydropterin(tetrahydro-1'-2'-dioxopterin) as intermediate.
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Abstract
Forty-nine patients with low serum and cerebrospinal fluid folate levels completed the Ottawa-Wechsler Scale after 7-11 months of folate supplementation (10 mg daily). Twelve patients exhibited major neurological symptoms, while 37 patients displayed depression and minor neurological signs. After folate therapy, Verbal, Performance and Full Wechsler scores were significantly improved (P less than 0.001). The order of improvement in scores on the Wechsler subtests (from the statistically most significant to the least as measured by the t-statistics) was: Block Design, Digit Symbol, Similarities, Picture Completion, Picture Arrangement, Arithmetic, Object Assembly, Digit Span, Information, and Comprehension.
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Duch DS, Woolf JH, Nichol CA, Davidson JR, Garbutt JC. Urinary excretion of biopterin and neopterin in psychiatric disorders. Psychiatry Res 1984; 11:83-9. [PMID: 6584938 DOI: 10.1016/0165-1781(84)90090-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Levels of urinary neopterin and biopterin were determined in patients having a diagnosis of schizophrenia, unipolar depression, or bipolar depression. Both neopterin and biopterin levels were significantly higher in the urine of patients with unipolar depression than in the urine of the control group. Subclassification of patients into primary and secondary depression demonstrated a significant elevation of urinary biopterin in both groups, whereas urinary neopterin was elevated only in those patients with primary depression. In patients with bipolar depression, neopterin excretion was elevated, but biopterin excretion did not differ from controls. No significant differences were found in schizophrenic patients.
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Kellner CH, Rakita RM, Rubinow DA, Gold PW, Ballenger JC, Post RM. Tetrahydrobiopterin levels in cerebrospinal fluid of affectively ill patients. Lancet 1983; 2:55-6. [PMID: 6134926 DOI: 10.1016/s0140-6736(83)90046-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Baker JT, Singh HM. Jaundice after cardiopulmonary bypass. Lancet 1983; 2:55. [PMID: 6134925 DOI: 10.1016/s0140-6736(83)90045-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Curtius HC, Niederwieser A, Levine RA, Lovenberg W, Woggon B, Angst J. Successful treatment of depression with tetrahydrobiopterin. Lancet 1983; 1:657-8. [PMID: 6131342 DOI: 10.1016/s0140-6736(83)91837-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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