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Untargeted metabolomic profiling reveals multiple pathway perturbations and new clinical biomarkers in urea cycle disorders. Genet Med 2019; 21:1977-1986. [PMID: 30670878 PMCID: PMC6650380 DOI: 10.1038/s41436-019-0442-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/09/2019] [Indexed: 12/30/2022] Open
Abstract
Purpose: Untargeted metabolomic analysis is increasingly being used in the screening and management of individuals with inborn errors of metabolism (IEM). We aimed to test whether untargeted metabolomic analysis in plasma might be useful for monitoring the disease course and management of urea cycle disorders (UCDs). Methods: Untargeted mass spectrometry-based metabolomic analysis was used to generate z-scores for more than 900 metabolites in plasma from 48 individuals with various UCDs. Pathway analysis was used to identify common pathways that were perturbed in each UCD. Results: Our metabolomic analysis in plasma identified multiple potentially neurotoxic metabolites of arginine in arginase deficiency and, thus, may have utility in monitoring the efficacy of treatment in arginase deficiency. In addition, we were also able to detect multiple biochemical perturbations in all UCDs that likely reflect clinical management, including metabolite alterations secondary to dietary and medication management. Conclusions: In addition to utility in screening for IEM, our results suggest that untargeted metabolomic analysis in plasma may be beneficial for monitoring efficacy of clinical management and off-target effects of medications in UCDs and potentially other IEM.
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Cai X, Yu D, Xie Y, Zhou H. Argininemia as a cause of severe chronic stunting and partial growth hormone deficiency (PGHD): A case report. Medicine (Baltimore) 2018; 97:e9880. [PMID: 29443755 PMCID: PMC5839826 DOI: 10.1097/md.0000000000009880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/21/2018] [Accepted: 01/24/2018] [Indexed: 11/26/2022] Open
Abstract
RATIONALE Argininemia is an autosomal recessive inherited disorder of the urea cycle. Because of its atypical symptoms in early age, diagnosis can be delayed until the typical chronic manifestations - including spastic diplegia, deterioration in cognitive function, and epilepsy - appear in later childhood. PATIENT CONCERNS A Chinese boy initially presented with severe stunting and partial growth hormone deficiency (PGHD) at 3 years old and was initially treated with growth hormone replacement therapy. Seven years later (at 10 years old), he presented with spastic diplegia, cognitive function lesions, epilepsy, and peripheral neuropathy. DIAGNOSES Ultimately, the patient was diagnosed with argininemia with homozygous mutation (c.32T>C) of the ARG1 gene at 10 years old. Blood tests showed mildly elevated blood ammonia and creatine kinase, and persistently elevated bilirubin. INTERVENTIONS Protein intake was limited to 0.8 g/kg/day, citrulline (150-200 mg [kg d]) was prescribed. OUTCOMES The patient's mental state and vomiting had improved after 3 months treatment. At 10 years and 9 month old, his height and weight had reached 121cm and 22kg, respectively, but his spastic diplegia symptoms had not improved. LESSONS This case demonstrates that stunting and PGHD that does not respond to growth hormone replacement therapy might hint at inborn errors of metabolism (IEM). IEM should also be considered in patients with persistently elevated bilirubin with or without abnormal liver transaminase, as well as elevated blood ammonia and creatine kinase, in the absence of hepatic disease.
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Affiliation(s)
- Xiaotang Cai
- Department of Pediatrics, West China Second University Hospital
- Key Laboratory of Obstetric and Gynaecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | - Dan Yu
- Department of Pediatrics, West China Second University Hospital
- Key Laboratory of Obstetric and Gynaecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | - Yongmei Xie
- Department of Pediatrics, West China Second University Hospital
- Key Laboratory of Obstetric and Gynaecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | - Hui Zhou
- Department of Pediatrics, West China Second University Hospital
- Key Laboratory of Obstetric and Gynaecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan, China
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Boyko A, Ksenofontov A, Ryabov S, Baratova L, Graf A, Bunik V. Delayed Influence of Spinal Cord Injury on the Amino Acids of NO • Metabolism in Rat Cerebral Cortex Is Attenuated by Thiamine. Front Med (Lausanne) 2018; 4:249. [PMID: 29379782 PMCID: PMC5775235 DOI: 10.3389/fmed.2017.00249] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 12/19/2017] [Indexed: 01/02/2023] Open
Abstract
Severe spinal cord injuries (SCIs) result in chronic neuroinflammation in the brain, associated with the development of cognitive and behavioral impairments. Nitric oxide (NO•) is a gaseous messenger involved in neuronal signaling and inflammation, contributing to nitrosative stress under dysregulated production of reactive nitrogen species. In this work, biochemical changes induced in the cerebral cortex of rats 8 weeks after SCI are assessed by quantification of the levels of amino acids participating in the NO• and glutathione metabolism. The contribution of the injury-induced neurodegeneration is revealed by comparison of the SCI- and laminectomy (LE)-subjected animals. Effects of the operative interventions are assessed by comparison of the operated (LE/SCI) and non-operated animals. Lower ratios of citrulline (Cit) to arginine (Arg) or Cit to ornithine and a more profound decrease in the ratio of lysine to glycine distinguish SCI animals from those after LE. The data suggest decreased NO• production from both Arg and homoarginine in the cortex 8 weeks after SCI. Both LE and SCI groups show a strong decrease in the level of cortex glutathione. The neurotropic, anti-inflammatory, and antioxidant actions of thiamine (vitamin B1) prompted us to study the thiamine effects on the SCI-induced changes in the NO• and glutathione metabolism. A thiamine injection (400 mg/kg intraperitoneally) within 24 h after SCI abrogates the changes in the cerebral cortex amino acids related to NO•. Thiamine-induced normalization of the brain glutathione levels after LE and SCI may involve increased supply of glutamate for glutathione biosynthesis. Thus, thiamine protects from sequelae of SCI on NO•-related amino acids and glutathione in cerebral cortex.
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Affiliation(s)
- Alexandra Boyko
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | - Alexander Ksenofontov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergey Ryabov
- Russian Cardiology Research-and-Production Complex, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Lyudmila Baratova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Anastasia Graf
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
- Faculty of Nano-, Bio-, Informational and Cognitive Technologies, Moscow Institute of Physics and Technology, Moscow, Russia
| | - Victoria Bunik
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
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The prognostic biomarker L-homoarginine is a substrate of the cationic amino acid transporters CAT1, CAT2A and CAT2B. Sci Rep 2017; 7:4767. [PMID: 28684763 PMCID: PMC5500509 DOI: 10.1038/s41598-017-04965-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 05/22/2017] [Indexed: 02/05/2023] Open
Abstract
Low plasma concentration of L-homoarginine is an independent predictor of cardiovascular events and total mortality. Experimental data indicate that supplementation of L-homoarginine may have protective effects. We aimed to elucidate the mechanisms involved in the cellular uptake of L-homoarginine, which are little understood, so far. Using human embryonic kidney (HEK293) cell lines stably overexpressing the human cationic amino acid transporters CAT1 [solute carrier family 7 (SLC7A1)], CAT2A (SLC7A2A) or CAT2B (SLC7A2B) we assessed the transport kinetics of L-homoarginine and interactions with the CAT substrates L-arginine and asymmetric dimethylarginine (ADMA). Significant uptake of L-homoarginine was observed for all three CATs with apparent KM-values of 175 ± 7 µM for CAT1 and 523 ± 35 µM for CAT2B. Saturation of CAT2A-mediated L-homoarginine uptake could not be reached. Uptake of L-homoarginine by any of the three CATs could be inhibited by L-arginine and ADMA. Significant inhibition of CAT1-mediated uptake of L-homoarginine by L-arginine already occurred in the physiological concentration range. Taken together these data demonstrate that L-homoarginine is a substrate of CAT1, CAT2A and CAT2B and that CAT1 is a key site with regard to physiological relevance and interactions with related substrates such as L-arginine.
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Delwing-de Lima D, Sasso S, Dalmedico L, Delwing-Dal Magro D, Pereira EM, Wyse ATS. Argininic acid alters markers of cellular oxidative damage in vitro: Protective role of antioxidants. ACTA ACUST UNITED AC 2017; 69:605-611. [PMID: 28554820 DOI: 10.1016/j.etp.2017.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/05/2017] [Accepted: 05/18/2017] [Indexed: 12/19/2022]
Abstract
We, herein, investigated the in vitro effects of argininic acid on thiobarbituric acid-reactive substances (TBA-RS), total sulfhydryl content and on the activities of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the blood, kidney and liver of 60-day-old rats. We also verified the influence of the antioxidants (each at 1.0mM) trolox and ascorbic acid, as well as of NG-nitro-l-arginine methyl ester (L-NAME) at 1.0mM, a nitric oxide synthase inhibitor, on the effects elicited by argininic acid on the parameters tested. The liver, renal cortex and renal medulla were homogenized in 10vol (1:10w/v) of 20mM sodium phosphate buffer, pH 7.4, containing 140mM KCl; and erythrocytes and plasma were prepared from whole blood samples obtained from rats. For in vitro experiments, the samples were pre-incubated for 1h at 37°C in the presence of argininic acid at final concentrations of 0.1, 1.0 and 5.0μM. Control experiments were performed without the addition of argininic acid. Results showed that argininic acid (5.0μM) enhanced CAT and SOD activities and decreased GSH-Px activity in the erythrocytes, increased CAT and decreased GSH-Px activities in the renal cortex and decreased CAT and SOD activities in the renal medulla of 60-day-old rats, as compared to the control group. Antioxidants and/or L-NAME prevented most of the alterations caused by argininic acid on the oxidative stress parameters evaluated. Data suggest that argininic acid alters antioxidant defenses in the blood and kidney of rats; however, in the presence of antioxidants and L-NAME, most of these alterations in oxidative stress were prevented. These findings suggest that oxidative stress may be make an important contribution to the damage caused by argininic acid in hyperargininemic patients and that treatment with antioxidants may be beneficial in this pathology.
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Affiliation(s)
- Daniela Delwing-de Lima
- Departamento de Medicina, Universidade da Região de Joinville - UNIVILLE, Rua Paulo Malschitzki, 10 - Zona Industrial Norte, CEP 89201-972, Joinville, SC, Brazil; Programa de Pós-Graduação em Saúde e Meio Ambiente, Universidade da Região de Joinville - UNIVILLE, Rua Paulo Malschitzki, 10 - Zona Industrial Norte, CEP 89201-972, Joinville, SC, Brazil.
| | - Simone Sasso
- Programa de Pós-Graduação em Saúde e Meio Ambiente, Universidade da Região de Joinville - UNIVILLE, Rua Paulo Malschitzki, 10 - Zona Industrial Norte, CEP 89201-972, Joinville, SC, Brazil
| | - Leticia Dalmedico
- Departamento de Farmácia, Universidade da Região de Joinville - UNIVILLE, Rua Paulo Malschitzki, 10 - Zona Industrial Norte, CEP 89201-972, Joinville, SC, Brazil
| | - Débora Delwing-Dal Magro
- Departamento de Ciências Naturais, Centro de Ciências Exatas e Naturais, Universidade Regional de Blumenau, Rua Antônio da Veiga, 140, CEP 89012-900, Blumenau, SC, Brazil
| | - Eduardo Manoel Pereira
- Departamento de Farmácia, Universidade da Região de Joinville - UNIVILLE, Rua Paulo Malschitzki, 10 - Zona Industrial Norte, CEP 89201-972, Joinville, SC, Brazil
| | - Angela T S Wyse
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, Brazil
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Rasic-Markovic A, Hrncic D, Krstic D, Colovic M, Djuric E, Rankov-Petrovic B, Susic V, Stanojlovic O, Djuric D. The effect of subchronic supplementation with folic acid and l-arginine on homocysteine-induced seizures. Can J Physiol Pharmacol 2016; 94:1083-1089. [DOI: 10.1139/cjpp-2016-0076] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The aim of the present study was to examine the effect of subchronic co-administration of folic acid (F) and l-arginine (A) on behavioural and electroencephalographic (EEG) characteristics of dl homocysteine thiolactone (H) induced seizures in adult rats. The activity of membrane ATPases in different brain regions were also investigated. Rats were treated with F, A, or vehicle for 15 days (regimen: F 5 mg/kg + A 500 mg/kg (F5A500); F 10 mg/kg + A 300 mg/kg (F10A300)). Seizures were elicited by convulsive dose of H (H, F5A500H, F10A300H) Subchronic supplementation with F and A did not affect seizure incidence, number of seizure episodes, and severity in F5A500H and F10A300H groups vs. H group. However, a tendency to increase latency and decrease the number of seizure episodes was noticed in the F10A300H group. EEG mean spectral power densities during ictal periods were significantly lower in F10A300H vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in rats treated with F and A. We can conclude that subchronic supplementation with folic acid and l-arginine has an antiepileptic effect in dl homocysteine thiolactone induced epilepsy.
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Affiliation(s)
- A. Rasic-Markovic
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - D. Hrncic
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - D. Krstic
- Institute of Medical Chemistry, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - M. Colovic
- Department of Physical Chemistry, Institute of Nuclear Sciences “Vinča”, University of Belgrade, M. Petrovic 12-14, P.O. Box 522, 11000 Belgrade, Serbia
| | - E. Djuric
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - B. Rankov-Petrovic
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - V. Susic
- Serbian Academy of Sciences and Arts, 11000 Belgrade, Serbia
| | - O. Stanojlovic
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - D. Djuric
- Institute of Medical Physiology “Richard Burian”, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
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7
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Atzler D, Schönhoff M, Cordts K, Ortland I, Hoppe J, Hummel FC, Gerloff C, Jaehde U, Jagodzinski A, Böger RH, Choe CU, Schwedhelm E. Oral supplementation with L-homoarginine in young volunteers. Br J Clin Pharmacol 2016; 82:1477-1485. [PMID: 27434056 DOI: 10.1111/bcp.13068] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 07/14/2016] [Accepted: 07/17/2016] [Indexed: 12/17/2022] Open
Abstract
AIMS Low blood concentrations of the naturally occurring amino acid L-homoarginine (L-hArg) are related to impaired cardiovascular outcome and mortality in humans and animals. L-hArg is a weak substrate of nitric oxide synthase and an inhibitor of arginases in vitro. The aim of our study was to obtain kinetic and dynamic data after oral L-hArg supplementation. METHODS In a double-blind, randomized, placebo-controlled crossover study, 20 young volunteers received 125 mg L-hArg once daily for 4 weeks. Kinetic parameters (Cmax , Tmax and AUC0-24h ) were calculated after ingestion of single and multiple doses of oral supplementation as primary endpoint. Secondary endpoints that were evaluated were routine laboratory, L-arginine, asymmetric dimethylarginine (ADMA), pulse wave velocity (PWV), augmentation index (AIx), flow-mediated vasodilatation (FMD), corticospinal excitability, i.e. motor threshold (MT), and cortical excitability, i.e. intracortical inhibition (ICI) and facilitation (ICF). RESULTS One hour after ingestion (Tmax ), L-hArg increased the baseline L-hArg plasma concentration (2.87 ± 0.91 μmol l-1 , mean ± SD) by 8.74 ± 4.46 [95% confidence intervals 6.65; 10.9] and 17.3 ± 4.97 [14.9; 19.6] μmol l-1 (Cmax ), after single and multiple doses, respectively. Once-only and 4 weeks of supplementation resulted in AUCs0-24h of 63.5 ± 28.8 [50.0; 76.9] and 225 ± 78.5 [188; 2624] μmol l-1 *h, for single and multiple doses, respectively. Routine laboratory parameters, L-arginine, ADMA, PWV, AIx, FMD, MT, ICI and ICF did not change by L-hArg supplementation compared to baseline. CONCLUSION Once daily orally applied 125 mg L-hArg raises plasma L-hArg four- and sevenfold after single dose and 4 weeks of supplementation, respectively, and is safe and well tolerated in young volunteers.
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Affiliation(s)
- Dorothee Atzler
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany.,Vascular Biology, Institute for Stroke and Dementia Research, Klinikum der Universität München Ludwig Maximilians-University of Munich, Munich, Germany
| | - Mirjam Schönhoff
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Kathrin Cordts
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany
| | - Imke Ortland
- Institute of Pharmacy Department of Clinical Pharmacy, University of Bonn, Bonn, Germany
| | - Julia Hoppe
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Friedhelm C Hummel
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Gerloff
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ulrich Jaehde
- Institute of Pharmacy Department of Clinical Pharmacy, University of Bonn, Bonn, Germany
| | - Annika Jagodzinski
- DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany.,Department of General and Interventional Cardiology, University Heart Center Hamburg-Eppendorf, Hamburg, Germany
| | - Rainer H Böger
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany
| | - Chi-Un Choe
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Edzard Schwedhelm
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany
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8
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Hyperargininemia due to arginase I deficiency: the original patients and their natural history, and a review of the literature. Amino Acids 2015; 47:1751-62. [DOI: 10.1007/s00726-015-2032-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 06/13/2015] [Indexed: 12/30/2022]
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9
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Sasso S, Dalmedico L, Delwing-Dal Magro D, Wyse ATS, Delwing-de Lima D. Effect ofN-acetylarginine, a metabolite accumulated in hyperargininemia, on parameters of oxidative stress in rats: protective role of vitamins and L-NAME. Cell Biochem Funct 2014; 32:511-9. [DOI: 10.1002/cbf.3045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Revised: 06/17/2014] [Accepted: 06/19/2014] [Indexed: 12/20/2022]
Affiliation(s)
- Simone Sasso
- Mestrado em Saúde e Meio Ambiente; Universidade da Região de Joinville-UNIVILLE; Joinville SC Brazil
| | - Leticia Dalmedico
- Departamento de Farmácia; Universidade da Região de Joinville-UNIVILLE; Joinville SC Brazil
| | - Débora Delwing-Dal Magro
- Departamento de Ciências Naturais, Centro de Ciências Exatas e Naturais; Universidade Regional de Blumenau; Blumenau SC Brazil
| | - Angela T. S. Wyse
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde; Universidade Federal do Rio Grande do Sul; Porto Alegre RS Brazil
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Guanidino compounds inhibit acetylcholinesterase and butyrylcholinesterase activities: Effect neuroprotector of vitamins E plus C. Int J Dev Neurosci 2010; 28:465-73. [DOI: 10.1016/j.ijdevneu.2010.06.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2010] [Revised: 06/12/2010] [Accepted: 06/16/2010] [Indexed: 11/21/2022] Open
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Nasrallah F, Feki M, Kaabachi N. Creatine and creatine deficiency syndromes: biochemical and clinical aspects. Pediatr Neurol 2010; 42:163-71. [PMID: 20159424 DOI: 10.1016/j.pediatrneurol.2009.07.015] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 06/10/2009] [Accepted: 07/30/2009] [Indexed: 11/28/2022]
Abstract
Creatine deficiency syndromes, which have only recently been described, represent a group of inborn errors of creatine synthesis (L-arginine-glycine amidinotransferase deficiency and guanidinoacetate methyltransferase deficiency) and transport (creatine transporter deficiency). Patients with creatine deficiency syndromes present with mental retardation expressive speech and language delay, and epilepsy. Patients with guanidinoacetate methyltransferase deficiency or creatine transporter deficiency may exhibit autistic behavior. The common denominator of these disorders is the depletion of the brain creatine pool, as demonstrated by in vivo proton magnetic resonance spectroscopy. For diagnosis, laboratory investigations start with analysis of guanidinoacetate, creatine, and creatinine in plasma and urine. Based on these findings, enzyme assays or DNA mutation analysis may be performed. The creatine deficiency syndromes are underdiagnosed, so the possibility should be considered in all children affected by unexplained mental retardation, seizures, and speech delay. Guanidinoacetate methyltransferase deficiency and arginine-glycine amidinotransferase deficiency are treatable by oral creatine supplementation, but patients with creatine transporter deficiency do not respond to this type of treatment.
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12
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Deignan JL, De Deyn PP, Cederbaum SD, Fuchshuber A, Roth B, Gsell W, Marescau B. Guanidino compound levels in blood, cerebrospinal fluid, and post-mortem brain material of patients with argininemia. Mol Genet Metab 2010; 100 Suppl 1:S31-6. [PMID: 20176499 DOI: 10.1016/j.ymgme.2010.01.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2010] [Revised: 01/13/2010] [Accepted: 01/13/2010] [Indexed: 10/19/2022]
Abstract
The paucity of hyperammonemic crises together with spasticity, only seen in human arginase I deficient patients and not in patients with other urea cycle disorders, forces a search for candidates other than ammonia to associate with the pathophysiology and symptomatology. Therefore, we determined arginine together with some catabolites of arginine in blood and cerebrospinal fluid of these patients as well as in extremely rare post-mortem brain material of two patients with argininemia. The levels of alpha-keto-delta-guanidinovaleric acid, argininic acid and alpha-N-acetylarginine correlate with the arginine levels in blood and cerebrospinal fluid of patients with imposed or spontaneous protein restriction. The levels in blood are higher than the upper limit of normal in all studied patients. In addition to the highly increased levels of these same compounds in blood of a child with argininemia, the increase of guanidinoacetic acid, 24h before death, is remarkable. However, the manifest increases of these studied catabolites of arginine are not seen in post-mortem brain material of the same pediatric patient. Otherwise a clear increase of guanidinoacetic acid in post-mortem brain material of an adult patient was shown. A similar, comparable increase of homoarginine in both studied post-mortem brain materials is observed. Therefore the study of the pathobiochemistry of arginine in argininemia must be completed in the future by the determination of the end catabolites of the nitric oxide and agmatine biosynthesis pathways in the knockouts as well as in the patients to evaluate their role, together with the here studied catabolites, as candidates for association with pathophysiology and symptomatology.
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Affiliation(s)
- Joshua L Deignan
- Department of Pathology, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
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13
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The Role of Nitric Oxide in Homocysteine Thiolactone-Induced Seizures in Adult Rats. Cell Mol Neurobiol 2009; 30:219-31. [DOI: 10.1007/s10571-009-9444-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Accepted: 08/11/2009] [Indexed: 12/24/2022]
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14
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Deignan JL, Marescau B, Livesay JC, Iyer RK, De Deyn PP, Cederbaum SD, Grody WW. Increased plasma and tissue guanidino compounds in a mouse model of hyperargininemia. Mol Genet Metab 2008; 93:172-8. [PMID: 17997338 DOI: 10.1016/j.ymgme.2007.09.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Accepted: 09/18/2007] [Indexed: 10/22/2022]
Abstract
In humans, arginase I (AI)-deficiency results in hyperargininemia, a metabolic disorder with symptoms of progressive neurological and intellectual impairment, spasticity, persistent growth retardation, and episodic hyperammonemia. A deficiency of arginase II (AII) has never been detected and the clinical disorder, if any, associated with its deficiency has not been defined. Since the spasticity and paucity of hyperammonemic crises seen in human AI-deficient patients are not features of the other urea cycle disorders, the likelihood of ammonia as the main neuropathogenic agent becomes extremely low, and the modest elevations of arginine seen in the brains of our mouse model of hyperargininemia make it an unlikely candidate as well. Specific guanidino compounds, direct or indirect metabolites of arginine, are elevated in the blood of patients with uremia. Other guanidino compounds are also increased in plasma and cerebrospinal fluid of hyperargininemic patients making them plausible as neurotoxins in these disorders. We analyzed several guanidino compounds in our arginase single and double knockout animals and found that alpha-keto-delta-guanidinovaleric acid, alpha-N-acetylarginine, and argininic acid were increased in the brain tissue from the AI knockout and double knockout animals. Several compounds were also increased in the plasma, liver, and kidneys. This is the first time that several of the guanidino compounds have been shown to be elevated in the brain tissue of an arginase-deficient mammal, and it further supports their possible role as the neuropathogenic agents responsible for the complications seen in arginase deficiency.
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Affiliation(s)
- Joshua L Deignan
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
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15
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Perasso L, Lunardi GL, Risso F, Pohvozcheva AV, Leko MV, Gandolfo C, Florio T, Cupello A, Burov SV, Balestrino M. Protective effects of some creatine derivatives in brain tissue anoxia. Neurochem Res 2007; 33:765-75. [PMID: 17940889 DOI: 10.1007/s11064-007-9492-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Accepted: 08/28/2007] [Indexed: 11/25/2022]
Abstract
Some derivatives more lipophylic than creatine, thus theoretically being capable to better cross the blood-brain barrier, were studied for their protective effect in mouse hippocampal slices. We found that N-amidino-piperidine is harmful to brain tissue, and that phosphocreatine is ineffective. Creatine, creatine-Mg-complex (acetate) and phosphocreatine-Mg-complex (acetate) increased the latency to population spike disappearance during anoxia. Creatine and creatine-Mg-complex (acetate) also increased the latency of anoxic depolarization, while the delay induced by phosphocreatine-Mg-complex (acetate) was of borderline significance (P = 0.056). Phosphocreatine-Mg-complex (acetate) significantly reduced neuronal hyperexcitability during anoxia, an effect that no other compound (including creatine itself) showed. For all parameters except reduced hyperexcitability the effects statistically correlated with tissue levels of creatine or phosphocreatine. Summing up, exogenous phosphocreatine and N-amidino piperidine are not useful for brain protection, while chelates of both creatine and phosphocreatine do replicate some of the known protective effects of creatine. In addition, phosphocreatine-Mg-complex (acetate) also reduced neuronal hyperexcitability during anoxia.
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Affiliation(s)
- Luisa Perasso
- Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Via De Toni 5, Genova 16132, Italy
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16
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Murphy TV, Kotecha N, Hill MA. Endothelium-independent constriction of isolated, pressurized arterioles by Nomega-nitro-L-arginine methyl ester (L-NAME). Br J Pharmacol 2007; 151:602-9. [PMID: 17471179 PMCID: PMC2013995 DOI: 10.1038/sj.bjp.0707262] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND AND PURPOSE Nitric oxide synthase (NOS) inhibitors cause vasoconstriction in pressurized arterioles with myogenic tone. This suggests either tonic production of NO modulates myogenic tone or a direct, NOS-independent effect of the NOS inhibitors. The nature of the contractile effect of the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM) on pressurised arterioles was investigated. EXPERIMENTAL APPROACH Segments of rat cremaster muscle first-order arteriole were cannulated on glass micropipettes and maintained at an intraluminal pressure of 50, 70 or 120 mmHg. KEY RESULTS L-NAME and the related compound L-NA (100 microM) constricted pressurized vessels with myogenic tone. Removal of the endothelium did not cause constriction or alter myogenic tone, however the constrictor effect of L-NAME persisted. The constrictor effect of L-NAME was abolished by L-arginine (1 mM). Other NO and cGMP pathway inhibitors, including the nNOS inhibitor 7-nitroindazole (100 muM), the NO scavenger carboxy-PTIO (100 microM), the guanylate cyclase inhibitor ODQ (10 microM) and the cGMP inhibitor Rp-8CPT-cGMPS (10 microM) did not cause constriction of the arterioles. L-NAME caused a small (3-4 mV) but not statistically significant depolarization of the arteriolar smooth muscle at both pressures. The constrictor effect was not prevented by the K(+)-channel antagonist tetraethyl ammonium (TEA, 1 mM) or the K(ATP) channel antagonist glibenclamide (1 microM). CONCLUSIONS AND IMPLICATIONS These observations demonstrate that L-NAME causes an endothelium- and NOS-independent contraction of vascular smooth muscle in isolated skeletal muscle arterioles. It is suggested that the underlying mechanism relates to an arginine binding interaction.
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Affiliation(s)
- T V Murphy
- Department of Physiology and Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.
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17
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Abstract
Recent observations in two patients, one with AGAT deficiency (AGAT-D) and one with GAMT deficiency (GAMT-D), both diagnosed already at birth, provide first evidence for important therapeutic effects of pre-symptomatic treatment with creatine (Cr) supplementation in AGAT-D and Cr supplementation plus guanidinoacetate lowering strategies in GAMT-D. Although long-term data are lacking, the results suggest that complete prevention of neurological sequelae in early treated patients could be feasible (Battini et al., 2006; Schulze et al., 2006).
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Affiliation(s)
- Andreas Schulze
- University of Toronto, Department of Paediatrics, Division of Clinical and Metabolic Genetics, and Research Institute, The Hospital for Sick Children, 555 University Avenue, Toronto, ON. M5G 1X8, Canada
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18
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da Silva AC, Balz D, de Souza JBD, Morsch VM, Corrêa MC, Zanetti GD, Manfron MP, Schetinger MRC. Inhibition of NTPDase, 5'-nucleotidase, Na+/K+-ATPase and acetylcholinesterase activities by subchronic treatment with Casearia sylvestris. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2006; 13:509-14. [PMID: 16785042 DOI: 10.1016/j.phymed.2005.01.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Accepted: 01/11/2005] [Indexed: 05/10/2023]
Abstract
The aqueous extract of Casearia sylvestris was tested in cortical membrane preparations. C. sylvestris was obtained commercially from two different sources, designated as Sample A and Sample B. The enzymes studied in this work were NTPDase-like, 5'-Nucleotidase, Na(+)/K(+)-ATPase and acetylcholinesterase (AChE). Adult rats received aqueous extracts from C. sylvestris in a dose of 20mg/kg body wt. daily for a 75-day-period, by oral administration (gavage). Our study showed that this treatment caused an inhibition of NTPDase-like activity with both, ATP (19.41% with Sample A and 25.03% with Sample B) and ADP (41.57% with Sample A and 31.20% with Sample B) as substrates. This treatment also caused an inhibition of 5'-nucleotidase activity (28.34% with Sample A and 31.46% with Sample B) and Na(+)/K(+)-ATPase (25.08% with Sample A and 24.81% with Sample B). The rate of acetylcholine degradation was reduced, as shown by the inhibition of AChE (31.65% and 26.74%, Samples A and B, respectively). These results suggest that extracts of C. sylvestris can cause neurochemical alterations in the purinergic and cholinergic systems of the central nervous system.
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Affiliation(s)
- A C da Silva
- Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
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19
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Scaglia F, Lee B. Clinical, biochemical, and molecular spectrum of hyperargininemia due to arginase I deficiency. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2006; 142C:113-20. [PMID: 16602094 PMCID: PMC4052756 DOI: 10.1002/ajmg.c.30091] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The urea cycle consists of six consecutive enzymatic reactions that convert waste nitrogen into urea. Urea cycle disorders are a group of inborn errors of hepatic metabolism that often result in life threatening hyperammonemia and hyperglutaminemia. Deficiencies of all of the enzymes of the cycle have been described and although each specific disorder results in the accumulation of different precursors, hyperammonemia and hyperglutaminemia are common biochemical hallmarks of these disorders. Arginase is the enzyme involved in the last step of the urea cycle. It catalyzes the conversion of arginine to urea and ornithine. The latter reenters the mitochondrion to continue the cycle. Hyperargininemia is an autosomal recessive disorder caused by a defect in the arginase I enzyme. Unlike other urea cycle disorders, this condition is not generally associated with a hyperammonemic encephalopathy in the neonatal period. It typically presents later in childhood between 2 and 4 years of age with predominantly neurological features. If untreated, it progresses with gradual developmental regression. A favorable outcome can be achieved if dietary treatment and alternative pathway therapy are instituted early in the disease course. With this approach, further neurological deterioration is prevented and partial recovery of skills ensues. Early diagnosis of this disorder through newborn screening programs may lead to a better outcome. This review article summarizes the clinical characterization of this disorder; as well as its biochemical, enzymatic, and molecular features. Treatment, prenatal diagnosis and diagnosis through newborn screening are also discussed.
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Affiliation(s)
- Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine and Texas Children's Hospital, Clinical Care Center Suite 1560, 6621 Fannin Street, Houston, TX 77030, USA.
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20
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Zugno AI, Scherer EBS, Schuck PF, Oliveira DL, Wofchuk S, Wannmacher CMD, Wajner M, Wyse ATS. Intrastriatal administration of guanidinoacetate inhibits Na+, K+-ATPase and creatine kinase activities in rat striatum. Metab Brain Dis 2006; 21:41-50. [PMID: 16773469 DOI: 10.1007/s11011-006-9003-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2005] [Accepted: 09/12/2005] [Indexed: 11/28/2022]
Abstract
Guanidinoacetate methyltransferase deficiency (GAMT deficiency) is an inherited neurometabolic disorder clinically characterized by epilepsy and mental retardation and biochemically by accumulation of guanidinoacetate (GAA) and depletion of creatine. Although this disease is predominantly characterized by severe neurological findings, the underlying mechanisms of brain injury are not yet established. In the present study, we investigated the effect of intrastriatal administration of GAA on Na+, K+-ATPase activity, total (tCK), cytosolic (Cy-CK), and mitochondrial (Mi-CK) creatine kinase (CK) activities in rat striatum. We verified that Na+, K+-ATPase, tCK, and Mi-CK activities were significantly inhibited by GAA, in contrast to Cy-CK which was not affected by this guanidino compound. Since these enzyme activities can be affected by reactive species, we also investigated the effect of intrastriatal administration of GAA on thiobarbituric acid reactive substances (TBARS), an index of lipid peroxidation in rats. We found that this metabolite significantly increased this oxidative stress parameter. Considering the importance of Na+, K+-ATPase and CK activities for brain metabolism homeostasis, our results suggest that the inhibition of these enzymes by increased intracerebral levels of GAA may contribute to the neuropathology observed in patients with GAMT-deficiency.
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Affiliation(s)
- Alexandra I Zugno
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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21
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22
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Delwing D, Gonçalves MCF, Sarkis JJF, Wyse ATS. L-NAME administration prevents the inhibition of nucleotide hydrolysis by rat blood serum subjected to hyperargininemia. Amino Acids 2005; 29:267-72. [PMID: 15977041 DOI: 10.1007/s00726-005-0216-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2004] [Accepted: 05/12/2005] [Indexed: 10/25/2022]
Abstract
The main objective of the present study was to evaluate the in vivo and in vitro effect of Arg on serum nucleotide hydrolysis. The action of Nomega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase, on the effects produced by Arg was also examined. Sixty-day-old rats were treated with a single or a triple (with an interval of 1 h between each injection) intraperitoneal injection of saline (group I), Arg (0.8 g/kg) (group II), L-NAME (2.0 mg/kg or 20 mg/kg) (group III) or Arg (0.8 g/kg) plus L-NAME (2.0 mg/kg or 20 mg/kg) (group IV) and were killed 1 h later. The present results show that a triple Arg administration decreased ATP, ADP and AMP hydrolysis. Simultaneous injection of L-NAME (20 mg/kg) prevented such effects. Arg in vitro did not alter nucleotide hydrolysis. It is suggested that in vivo Arg administration reduces nucleotide hydrolysis in rat serum, probably through nitric oxide or/and peroxynitrite formation.
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Affiliation(s)
- D Delwing
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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23
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Scaglia F, Brunetti-Pierri N, Kleppe S, Marini J, Carter S, Garlick P, Jahoor F, O'Brien W, Lee B. Clinical consequences of urea cycle enzyme deficiencies and potential links to arginine and nitric oxide metabolism. J Nutr 2004; 134:2775S-2782S; discussion 2796S-2797S. [PMID: 15465784 DOI: 10.1093/jn/134.10.2775s] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Urea cycle disorders (UCD) are human conditions caused by the dysregulation of nitrogen transfer from ammonia nitrogen into urea. The biochemistry and the genetics of these disorders were well elucidated. Earlier diagnosis and improved treatments led to an emerging, longer-lived cohort of patients. The natural history of some of these disorders began to point to pathophysiological processes that may be unrelated to the primary cause of acute morbidity and mortality, i.e., hyperammonemia. Carbamyl phosphate synthetase I single nucleotide polymorphisms may be associated with altered vascular resistance that becomes clinically relevant when specific environmental stressors are present. Patients with argininosuccinic aciduria due to a deficiency of argininosuccinic acid lyase are uniquely prone to chronic hepatitis, potentially leading to cirrhosis. Moreover, our recent observations suggest that there may be an increased prevalence of essential hypertension. In contrast, hyperargininemia found in patients with arginase 1 deficiency is associated with pyramidal tract findings and spasticity, without significant hyperammonemia. An intriguing potential pathophysiological link is the dysregulation of intracellular arginine availability and its potential effect on nitric oxide (NO) metabolism. By combining detailed natural history studies with the development of tissue-specific null mouse models for urea cycle enzymes and measurement of nitrogen flux through the cycle to urea and NO in UCD patients, we may begin to dissect the contribution of different sources of arginine to NO production and the consequences on both rare genetic and common multifactorial diseases.
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Affiliation(s)
- Fernando Scaglia
- Department of Molecular and Human Genetics, Children's Nutritional Research Center, Baylor College of Medicine, Houston, TX 77030, USA
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24
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Matté C, Monteiro SC, Calcagnotto T, Bavaresco CS, Netto CA, Wyse ATS. In vivo and in vitro effects of homocysteine on Na+,K+‐ATPase activity in parietal, prefrontal and cingulate cortex of young rats. Int J Dev Neurosci 2004; 22:185-90. [PMID: 15245753 DOI: 10.1016/j.ijdevneu.2004.05.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Revised: 05/11/2004] [Accepted: 05/19/2004] [Indexed: 10/26/2022] Open
Abstract
In the present study we determined the effect of chronic administration of homocysteine on Na+,K+-ATPase activity in synaptic membranes from parietal, prefrontal and cingulate cortex of young rats. We also studied the in vitro effect of homocysteine on this enzyme activity and on some oxidative stress parameters, namely thiobarbituric acid-reactive substances (TBA-RS) and total radical-trapping antioxidant potential (TRAP) in the same cerebral structures. For the in vivo studies, we induced elevated levels of homocysteine in blood (500 microM), comparable to those of human homocystinuria, and in brain (60 nmol/g wet tissue) of young rats by injecting subcutaneously homocysteine (0.3-0.6 micromol/g of body weight) twice a day at 8 h intervals from the 6th to the 28th postpartum day. Controls received saline in the same volumes. Rats were killed 12 h after the last injection. Chronic administration of homocysteine significantly decreased (50%) Na+,K+-ATPase activity in parietal, increased (36%) in prefrontal and did not alter in cingulate cortex of young rats. In vitro homocysteine decreased Na+,K+-ATPase activity and TRAP and increased TBA-RS in all cerebral structures studied. It is proposed that the alteration of Na+,K+-ATPase and induction of oxidative stress by homocysteine in cerebral cortex may be one of the mechanisms related to the neuronal dysfunction observed in human homocystinuria.
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Affiliation(s)
- Cristiane Matté
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600 Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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25
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Zugno AI, Franzon R, Chiarani F, Bavaresco CS, Wannmacher CMD, Wajner M, Wyse ATS. Evaluation of the mechanism underlying the inhibitory effect of guanidinoacetate on brain Na
+
, K
+
‐ATPase activity. Int J Dev Neurosci 2004; 22:191-6. [PMID: 15245754 DOI: 10.1016/j.ijdevneu.2004.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2004] [Revised: 05/03/2004] [Accepted: 05/04/2004] [Indexed: 11/15/2022] Open
Abstract
Guanidinoacetate methyltransferase deficiency (GAMT-deficiency) is an inherited neurometabolic disorder clinically characterized by epilepsy and mental retardation and biochemically by accumulation of guanidinoacetate (GAA) and depletion of creatine. Although the neurological symptoms are predominant, the pathogenesis of the brain dysfunction in this disorder is not yet established. In the present study we investigated the in vitro effect of GAA on Na+, K+-ATPase and Mg2+-ATPase activities in synaptic plasma membrane from hippocampus of young rats. Results showed that GAA significantly inhibited Na+, K+-ATPase activity without affecting Mg2+-ATPase activity. We also evaluated the effect of glutathione (GSH), trolox, Nomega-nitro-L-arginine methyl ester (L-NAME) and taurine (Tau) on the inhibition elicited by GAA on Na+, K+-ATPase activity. GSH, trolox, L-NAME and Tau per se did not alter Na+, K+-ATPase activity. However, L-NAME and taurine prevented the inhibitory effect of GAA on this enzyme activity. Our findings suggest that the inhibition of Na+, K+-ATPase activity caused by GAA is possibly mediated by nitric oxide (NO) formation and/or synaptic membrane alteration. The present data may contribute to the understanding of the neurological dysfunction characteristic of GAMT-deficient patients.
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Affiliation(s)
- Alexandra I Zugno
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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26
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Bavaresco CS, Zugno AI, Tagliari B, Wannmacher CMD, Wajner M, Wyse ATS. Inhibition of Na+, K+-ATPase activity in rat striatum by the metabolites accumulated in Lesch-Nyhan disease. Int J Dev Neurosci 2004; 22:11-7. [PMID: 15013074 DOI: 10.1016/j.ijdevneu.2003.11.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2003] [Revised: 11/18/2003] [Accepted: 11/20/2003] [Indexed: 02/04/2023] Open
Abstract
In the present study, we investigated the in vitro effect of hypoxanthine, xanthine and uric acid, metabolites accumulating in tissue of patients with Lesch-Nyhan disease, on Na(+), K(+)-ATPase activity in striatum of neonate rats. Results showed that all compounds significantly inhibited Na(+), K(+)-ATPase activity. We also studied the kinetics of the inhibition of Na(+), K(+)-ATPase activity caused by hypoxanthine. The apparent K(m) and V(max) of Na(+), K(+)-ATPase activity for ATP as the substrate and hypoxanthine as the inhibitor were 0.97 mM and 0.69 nmol inorganic phosphate (Pi) released per min per mg of protein, respectively. K(i)-value was 1.9 microM, and the inhibition was of the non-competitive type. We also observed that the inhibitory effects of hypoxanthine, xanthine and uric acid probably occur through the same mechanism, suggesting a common binding site for these oxypurines on Na(+), K(+)-ATPase. Therefore, it is conceivable that inhibition of brain Na(+), K(+)-ATPase activity may be involved at least in part in the neuronal dysfunction characteristic of patients with Lesch-Nyhan disease.
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Affiliation(s)
- Caren S Bavaresco
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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27
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Zugno AI, Stefanello FM, Streck EL, Calcagnotto T, Wannmacher CMD, Wajner M, Wyse ATS. Inhibition of Na+, K+-ATPase activity in rat striatum by guanidinoacetate. Int J Dev Neurosci 2003; 21:183-9. [PMID: 12781785 DOI: 10.1016/s0736-5748(03)00038-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The aim of this work was to investigate the effect of guanidinoacetate (GAA), the principal metabolite accumulating in guanidinoacetate methyltransferase (GAMT)-deficiency, on Na(+), K(+)-ATPase, Mg(2+)-ATPase and acetylcholinesterase (AChE) activities in striatum of young rats. We also studied the kinetics of the inhibition of Na(+), K(+)-ATPase activity caused by guanidinoacetate. Guanidinoacetate did not alter acetylcholinesterase and Mg(2+)-ATPase activities, but significantly inhibited Na(+), K(+)-ATPase activity. The apparent K(m) and V(max) of Na(+), K(+)-ATPase for ATP as substrate were 0.20mM and 0.82nmol inorganic phosphate (Pi) released per min per mg of protein, respectively. K(i) value was 7.18mM, and the inhibition was of the uncompetitive type. The results also showed a competition between guanidinoacetate and argininic acid (AA), suggesting a common binding site for the guanidino compounds (GC) on the enzyme. It is proposed that Na(+), K(+)-ATPase inhibition by guanidinoacetate may be one of the mechanisms involved in the neuronal dysfunction observed in GAMT-deficiency and in other diseases which accumulate guanidinoacetate.
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Affiliation(s)
- Alexandra I Zugno
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003 Porto Alegre, RS, Brazil
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28
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Balz D, de Souza Wyse AT, Morsch VM, da Silva AC, Vieira VL, Morsch ALB, Schetinger MRC. In vitro effects of L-arginine and guanidino compounds on NTPDase1 and 5'-nucleotidase activities from rat brain synaptosomes. Int J Dev Neurosci 2003; 21:75-82. [PMID: 12615083 DOI: 10.1016/s0736-5748(02)00138-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Tissue accumulation of arginine (Arg), N-acetylarginine (NA), argininic acid (AA) and homoarginine (HA) occurs in hyperargininemia, an inborn error of the urea cycle. In the present study, we investigated the in vitro effects of Arg, NA, AA and HA on NTPDase1 and 5'-nucleotidase activities from synaptosomal cerebral cortex of rats. The results showed that Arg enhances NTPDase1 activity at the high concentrations tested (1.5 and 3.0mM) for both the ATP and ADP nucleotides. Activation was also observed with other guanidino compounds tested: NA, AA and HA activated ATP and ADP hydrolysis in all experiments at the concentration of 25 microM. Besides this, NA and AA activated ATP hydrolysis at a lower concentration (1 microM). In another set of experiments, we verified the effect of Arg on purified apyrase at pH 8.0 and 6.5 and observed an increase in the enzyme activity at all Arg concentrations tested (0.01-3.0mM). In contrast, Arg and the other guanidino compounds tested did not alter 5'-nucleotidase activity. These results suggest that changes in nucleotide hydrolysis may be involved in the brain dysfunction caused by hyperargininemia amongst other potential pathophysiological mechanisms involved in this condition.
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Affiliation(s)
- Daniela Balz
- Departamento de Qui;mica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, RS, Santa Maria, Brazil
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29
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dos Reis EA, de Oliveira LS, Lamers ML, Netto CA, Wyse ATDS. Arginine administration inhibits hippocampal Na+,K+-ATPase activity and impairs retention of an inhibitory avoidance task in rats. Brain Res 2002; 951:151-7. [PMID: 12270492 DOI: 10.1016/s0006-8993(02)03077-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the present study we investigated the effect of acute administration of L-arginine (Arg) on hippocampal Na(+),K(+)-ATPase activity and on retrieval of step-down inhibitory avoidance in adult rats. The action of L-NAME on the effects produced by Arg was also tested. Sixty-day-old rats were treated with a single intraperitoneal injection of saline (group I, control), arginine (0.8 g/kg) (group II), L-NAME (2 mg/kg) (group III) or arginine (0.8 g/kg) plus L-NAME (2 mg/kg) (group IV). Na(+),K(+)-ATPase activity was significantly reduced in arginine-treated rats; this effect was prevented by L-NAME. Retrieval of the avoidance task was also significantly impaired by arginine, whereas the simultaneous injection of L-NAME prevented this effect. Present data strongly indicate that in vivo Arg administration reduces both Na(+),K(+)-ATPase activity and memory modulation in rats probably through NO formation.
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Affiliation(s)
- Eleonora Araújo dos Reis
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, RS, Porto Alegre, Brazil
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Streck EL, Zugno AI, Tagliari B, Wannmacher C, Wajner M, Wyse ATS. Inhibition of Na+, K+-ATPase activity by the metabolites accumulating in homocystinuria. Metab Brain Dis 2002; 17:83-91. [PMID: 12083340 DOI: 10.1023/a:1015594111778] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Homocystinuria is an inborn error of sulfur amino acid metabolism characterized predominantly by vascular and nervous system dysfunction. In this study we determined the in vitro effects of homocysteine and methionine, metabolites which accumulate in homocystinuria, on Na+, K+-ATPase, and Mg2+-ATPase activities in synaptic membranes from the hippocampus of rats. The results showed that both metabolites significantly inhibit Na+, K+-ATPase but not Mg2+-ATPase activity at concentrations usually observed in plasma of homocystinuric patients. Furthermore, incubation of hippocampal homogenates with homocysteine also elicited an inhibition of the enzyme activity which was however prevented by the simultaneous addition of cysteine to the medium. In addition, cysteine or methionine per se did not modify the two enzymatic activities. These findings indicate that oxidation of critical groups in the enzyme may possibly be involved in homocysteine inhibitory effect. Moreover, kinetic studies performed to investigate the interaction between homocysteine and methionine on Na+, K+-ATPase inhibition suggested a common site for the two amino acids in the enzyme. Considering the critical role exerted by Na+, K+-ATPase in brain, it is proposed that the inhibition provoked by homocysteine and methionine on the enzyme activity may be possibly related to the brain dysfunction characteristic of homocystinuria.
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Affiliation(s)
- Emilio L Streck
- Departamento de Bioquímica, Instituto de Ciências Básicas de Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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31
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Streck EL, Zugno AI, Tagliari B, Sarkis JJF, Wajner M, Wannmacher CMD, Wyse ATS. On the mechanism of the inhibition of Na(+), K(+)-ATPase activity caused by homocysteine. Int J Dev Neurosci 2002; 20:77-81. [PMID: 12034138 DOI: 10.1016/s0736-5748(02)00043-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In the present work, we investigated the kinetics of the inhibition of Na(+), K(+)-ATPase activity caused by homocysteine (Hcy) in rat hippocampus. We also studied the interaction between Hcy and phenylalanine (Phe) and the kinetics of alanine (Ala) reversal of the inhibition of Na(+), K(+)-ATPase caused by Hcy. The apparent K(m) and V(max) of Na(+), K(+)-ATPase for ATP as substrate were 0.55mM and 2.0nmol Pi released per min per mg of protein, respectively. K(i) value was approximately 0.1mM, and the inhibition was of the non-competitive type. The results also showed a competition between Hcy and Phe. Ala per se did not alter this enzyme, but prevented the inhibitory effect caused by Hcy, suggesting a common binding site for these substances. It is proposed that the inhibition of Na(+), K(+)-ATPase by Hcy may be one of the mechanisms related to the neuronal dysfunction observed in human homocystinuria.
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Affiliation(s)
- Emilio L Streck
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP, 90035-003 Porto Alegre, RS, Brazil
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32
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Wyse AT, Bavaresco CS, Hagen ME, Delwing D, Wannmacher CM, Severo Dutra-Filho C, Wajner M. In vitro stimulation of oxidative stress in cerebral cortex of rats by the guanidino compounds accumulating in hyperargininemia. Brain Res 2001; 923:50-7. [PMID: 11743972 DOI: 10.1016/s0006-8993(01)03197-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hyperargininemia is a metabolic disorder biochemically characterized by tissue accumulation of arginine and other guanidino compounds. Convulsions, lethargy and psychomotor delay or cognitive deterioration are predominant clinical features of this disease. Although neurologic symptoms predominate in this disorder, their pathophysiology is still unknown. In the present study we investigated the in vitro effects of arginine, N-acetylarginine, argininic acid and homoarginine on some oxidative stress parameters in rat brain in the hope to identify a possible mechanism for the brain damage in hyperargininemia. Chemiluminescence, total radical-trapping antioxidant potential (TRAP), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were measured in the cerebral cortex of rats in the presence of various concentrations of these compounds. The results showed that all guanidino compounds tested significantly increased chemiluminescence and decreased TRAP at concentrations similar to those observed in the tissue of hyperargininemic patients. Furthermore, these compounds inhibited CAT and GSH-Px activities to varying extents, with GSH-Px activity being more susceptible to their action. In turn, argininic acid inhibited all enzyme activities, and its main action was also directed towards GSH-Px. The results suggest that oxidative stress caused by guanidino compounds may be involved in the brain dysfunction amongst other potential pathophysiological mechanisms observed in hyperargininemia.
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Affiliation(s)
- A T Wyse
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre RS, Brazil.
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Schulze A, Ebinger F, Rating D, Mayatepek E. Improving treatment of guanidinoacetate methyltransferase deficiency: reduction of guanidinoacetic acid in body fluids by arginine restriction and ornithine supplementation. Mol Genet Metab 2001; 74:413-9. [PMID: 11749046 DOI: 10.1006/mgme.2001.3257] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Guanidinoacetate methyltransferase (GAMT) deficiency (McKusick 601240), an inborn error of creatine biosynthesis, is characterized by creatine depletion and accumulation of guanidinoacetate (GAA) in the brain. Treatment by oral creatine supplementation had no effect on the intractable seizures. Based on the possible role of GAA as an epileptogenic agent, we evaluated a dietary treatment with arginine restriction and ornithine supplementation in order to achieve reduction of GAA. In an 8-year-old Kurdish girl with GAMT deficiency arginine intake was restricted to 15 mg/kg/day (0.4 g natural protein/kg/day) and ornithine was supplemented with 100 mg/kg/day over a period of 14 months. The diet was enriched with 0.4 g/kg/day of arginine-free essential amino acid mixture and creatine treatment remained unchanged (1.1 g/kg/day). Guanidino compounds in blood, urine, and CSF were measured by means of cation-exchange chromatography. The combination of arginine restriction and ornithine supplementation led to a substantial and permanent decrease of arginine without disturbance of nitrogen detoxification. Formation of GAA was effectively reduced after 4 weeks of treatment and sustained thereafter. Biochemical effects were accompanied by a marked clinical improvement. Distinctly reduced epileptogenic activities in electroencephalography accompanied by almost complete disappearance of seizures demonstrates the positive effect of GAA reduction. This indicates for the first time that GAA may exert an important epileptogenic potential in man. Arginine restriction in combination with ornithine supplementation represents a new and rationale therapeutic approach in GAMT deficiency.
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Affiliation(s)
- A Schulze
- Department of General Pediatrics, Division of Metabolic and Endocrine Diseases, University Children's Hospital, Im Neuenheimer Feld 150, Heidelberg, 69120, Germany.
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de Jonge WJ, Marescau B, D'Hooge R, De Deyn PP, Hallemeesch MM, Deutz NE, Ruijter JM, Lamers WH. Overexpression of arginase alters circulating and tissue amino acids and guanidino compounds and affects neuromotor behavior in mice. J Nutr 2001; 131:2732-40. [PMID: 11584097 DOI: 10.1093/jn/131.10.2732] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Arginine is an intermediate of the ornithine cycle and serves as a precursor for the synthesis of nitric oxide, creatine, agmatine and proteins. It is considered to be a conditionally essential amino acid because endogenous synthesis only barely meets daily requirements. In rapidly growing suckling neonates, endogenous arginine biosynthesis is crucial to compensate for the insufficient supply of arginine via the milk. Evidence is accumulating that the intestine rather than the kidney plays a major role in arginine synthesis in this period. Accordingly, ectopic expression of hepatic arginase in murine enterocytes by genetic modification induces a selective arginine deficiency. The ensuing phenotype, whose severity correlates with the level of transgene expression in the enterocytes, could be reversed with arginine supplementation. We analyzed the effect of arginine deficiency on guanidine metabolism and neuromotor behavior. Arginine-deficient transgenic mice continued to suffer from an arginine deficiency after the arginine biosynthetic enzymes had disappeared from the enterocytes. Postweaning catch-up growth in arginine-deficient mice was characterized by increased levels of all measured amino acids except arginine. Furthermore, plasma total amino acid concentration, including arginine, was significantly lower in adult male than in adult female transgenic mice. Decreases in the concentration of plasma and tissue arginine led to significant decreases in most metabolites of arginine. However, the accumulation of the toxic guanidino compounds, guanidinosuccinic acid and methylguanidine, corresponded inversely with circulating arginine concentration, possibly reflecting a higher oxidative stress under hypoargininemic conditions. In addition, hypoargininemia was associated with disturbed neuromotor behavior, although brain levels of toxic guanidino compounds and ammonia were normal.
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Affiliation(s)
- W J de Jonge
- Department of Anatomy & Embryology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
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Wyse AT, Bavaresco CS, Bandinelli C, Streck EL, Franzon R, Dutra-Filho CS, Wajner M. Nitric oxide synthase inhibition by L-NAME prevents the decrease of Na+,K+-ATPase activity in midbrain of rats subjected to arginine administration. Neurochem Res 2001; 26:515-20. [PMID: 11513478 DOI: 10.1023/a:1010912929042] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In the present study we investigated the effect of acute administration of L-arginine on Na(+),K(+)-ATPase and Mg(2+)-ATPase activities and on some parameters of oxidative stress (chemiluminescence and total radical-trapping antioxidant parameter-TRAP) in midbrain of adult rats. We also tested the effect of L-NAME on the effects produced by arginine. Sixty-day-old rats were treated with an acute intraperitoneal injection of saline (group I, control), arginine (0.8 g/kg) (group II), L-NAME (2 mg/kg) (group III) or arginine (0.8 g/kg) plus L-NAME (2 mg/kg) (group IV). Na(+),K(+)-ATPase activity was significantly reduced in the arginine-treated rats, but was not affected by other treatments. In contrast, Mg(2+)-ATPase activity was not altered by any treatment. Furthermore, chemiluminescence was significantly increased and TRAP was significantly decreased in arginine-treated rats, whereas the simultaneous injection of L-NAME prevented these effects. These results demonstrate that in vivo arginine administration reduces Na(+),K(+)-ATPase activity possibly through free radical generation induced by NO formation.
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Affiliation(s)
- A T Wyse
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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Streck EL, Edom PT, Noriler ME, Borges LF, Pontes ZL, Parolo E, Dutra-Filho CS, Wannmacher CM, Wyse AT. Effect of phenylalanine and p-chlorophenylalanine on Na+, K+-ATPase activity in the synaptic plasma membrane from the cerebral cortex of rats. Metab Brain Dis 2000; 15:105-14. [PMID: 11092577 DOI: 10.1007/bf02679977] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Na+, K+-ATPase activity was measured in synaptic plasma membrane from cerebral cortex of Wistar rats subjected to experimental phenylketonuria, i.e., chemical hyperphenylalaninemia induced by subcutaneous administration of 5.2 micromol phenylalanine / g body weight (twice a day) plus 0.9 micromol p-chlorophenylalanine / g body weight (once a day). The treatment was performed from the 6th to the 14th postpartum day and rats were killed 12 h after the last injection. Synaptic plasma membrane from cerebral cortex was prepared by a discontinuous density sucrose gradient for Na+, K+-ATPase activity determination. The results showed that the enzyme activity was decreased by 30% in animals subjected to experimental phenylketonuria when compared to control. The in vitro effects of the drugs on Na+, K+-ATPase activity were also investigated. Phenylalanine and p-chlorophenylalanine inhibited the enzyme activity and this inhibition was reversed by alanine. In addition, competition between phenylalanine and p-chlorophenylalanine for binding to the enzyme was observed, suggesting a common binding site for these substances. Our results suggest that reduction of Na+, K+-ATPase activity may be one of the mechanisms related to the brain dysfunction observed in human PKU.
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Affiliation(s)
- E L Streck
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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