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Bregalda A, Carducci C, Pascucci T, Ambrogini P, Sartini S, Pierigè F, di Carlo E, Fiori E, Ielpo D, Pagliarini M, Leuzzi V, Magnani M, Rossi L. New findings about neuropathological outcomes in the PKU mouse throughout lifespan. Mol Genet Metab 2024; 143:108543. [PMID: 39047302 DOI: 10.1016/j.ymgme.2024.108543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/17/2024] [Accepted: 07/17/2024] [Indexed: 07/27/2024]
Abstract
Phenylketonuria (PKU, OMIM 261600) is a genetic disorder caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). If left untreated, PKU leads to systemic phenylalanine (Phe) accumulation, which can result in irreversible brain damage and intellectual disabilities. In the last 60 years, early and strict dietary restriction of phenylalanine (Phe) intake proved to prevent the severe clinical phenotype of untreated PKU. While the specific mechanisms through which phenylalanine causes brain damage are still poorly understood, preclinical models have been deeply explored to characterize the neurotoxic effect of Phe on neurodevelopmental processes. At the same time, that on the aging brain still needs to be explored. In the brain of untreated PAHEnu2(-/-) mouse, we previously reported a reduction of myelin basic protein (MBP) during postnatal development up to 60 PND. Later in the diseased mouse's life, a spontaneous and persistent restoration of MBP was detected. In this present longitudinal study, ranging from 14 to 540 post-natal days (PND) of untreated PAHEnu2(-/-) mice, we further investigated: a) the long-life consistency of two Phe-related brain metabolic alterations, such as large neutral amino acids (LNAA) and biogenic amine neurotransmitters' depletion; b) the outcome of locomotor functions during the same life span; c) the integrity of myelin as assessed ex vivo by central (hippocampus) and peripheral (extensor digitorum longus-sciatic nerve) action potential conduction velocities. In contrast with the results of other studies, brain Leu, Ile, and Val concentrations were not significantly altered in the brain PAHEnu2(-/-) mouse. On the other hand, 3-O-Methyldopa (3-OMD, a biomarker of L-DOPA), serotonin, and its associated metabolites were reduced throughout most of the considered time points, with consistent reductions observed prevalently from 14 to 60 PND. Normal saltatory conduction was restored after 60 PND and remained normal at the last examination at 360 PND, resulting nonetheless in a persistent locomotor impairment throughout a lifetime. These new findings contribute to laying the foundations for the preclinical characterization of aging in PKU, confirming neurotransmitter defects as consistent metabolic traits. LNAAs have a minor role, if any, in brain damage pathogenesis. Transient myelin synthesis failure may impact brain connectivity during postnatal development but not nervous signal conduction.
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Affiliation(s)
- Alessandro Bregalda
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy; Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, via Franco Gallini 2, 33081 Aviano (PN), Italy.
| | - Claudia Carducci
- Department of Experimental Medicine, Sapienza University, viale del Policlinico 155, 00161 Rome, Italy
| | - Tiziana Pascucci
- Fondazione Santa Lucia IRCCS, via Del Fosso di Fiorano, 64, 00143 Rome, Italy; Department of Psychology and Centro "Daniel Bovet", Sapienza University, via dei Marsi 78, 00185 Rome, Italy
| | - Patrizia Ambrogini
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy
| | - Stefano Sartini
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy
| | - Francesca Pierigè
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy
| | - Emanuele di Carlo
- Department of Experimental Medicine, Sapienza University, viale del Policlinico 155, 00161 Rome, Italy
| | - Elena Fiori
- Fondazione Santa Lucia IRCCS, via Del Fosso di Fiorano, 64, 00143 Rome, Italy; Technopole Foundation, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Donald Ielpo
- Fondazione Santa Lucia IRCCS, via Del Fosso di Fiorano, 64, 00143 Rome, Italy; Department of Psychology and Centro "Daniel Bovet", Sapienza University, via dei Marsi 78, 00185 Rome, Italy
| | - Marica Pagliarini
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Sapienza University, via dei Sabelli 108, 00185 Rome, Italy
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso (MI), Italy
| | - Luigia Rossi
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Ca' Le Suore 2, 61029 Urbino (PU), Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso (MI), Italy
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2
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van Wegberg AMJ, van der Weerd JC, Engelke UFH, Coene KLM, Jahja R, Bakker SJL, Huijbregts SCJ, Wevers RA, Heiner-Fokkema MR, van Spronsen FJ. The clinical relevance of novel biomarkers as outcome parameter in adults with phenylketonuria. J Inherit Metab Dis 2024; 47:624-635. [PMID: 38556470 DOI: 10.1002/jimd.12732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/07/2024] [Accepted: 03/12/2024] [Indexed: 04/02/2024]
Abstract
Recent studies in PKU patients identified alternative biomarkers in blood using untargeted metabolomics. To test the added clinical value of these novel biomarkers, targeted metabolomics of 11 PKU biomarkers (phenylalanine, glutamyl-phenylalanine, glutamyl-glutamyl-phenylalanine, N-lactoyl-phenylalanine, N-acetyl-phenylalanine, the dipeptides phenylalanyl-phenylalanine and phenylalanyl-leucine, phenylalanine-hexose conjugate, phenyllactate, phenylpyruvate, and phenylacetate) was performed in stored serum samples of the well-defined PKU patient-COBESO cohort and a healthy control group. Serum samples of 35 PKU adults and 20 healthy age- and sex-matched controls were analyzed using ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry. Group differences were tested using the Mann-Whitney U test. Multiple linear regression analyses were performed with these biomarkers as predictors of (neuro-)cognitive functions working memory, sustained attention, inhibitory control, and mental health. Compared to healthy controls, phenylalanine, glutamyl-phenylalanine, N-lactoyl-phenylalanine, N-acetyl-phenylalanine, phenylalanine-hexose conjugate, phenyllactate, phenylpyruvate, and phenylacetate were significant elevated in PKU adults (p < 0.001). The remaining three were below limit of detection in PKU and controls. Both phenylalanine and N-lactoyl-phenylalanine were associated with DSM-VI Attention deficit/hyperactivity (R2 = 0.195, p = 0.039 and R2 = 0.335, p = 0.002, respectively) of the ASR questionnaire. In addition, N-lactoyl-phenylalanine showed significant associations with ASR DSM-VI avoidant personality (R2 = 0.265, p = 0.010), internalizing (R2 = 0.192, p = 0.046) and externalizing problems (R2 = 0.217, p = 0.029) of the ASR questionnaire and multiple aspects of the MS2D and FI tests, reflecting working memory with R2 between 0.178 (p = 0.048) and 0.204 (p = 0.033). Even though the strength of the models was not considered strong, N-lactoyl-phenylalanine outperformed phenylalanine in its association with working memory and mental health outcomes.
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Affiliation(s)
- A M J van Wegberg
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, The Netherlands
| | - J C van der Weerd
- Department of Laboratory Medicine, Laboratory of Metabolic Diseases, University of Groningen, University Medical Centre Groningen, The Netherlands
| | - U F H Engelke
- Department of Human Genetics, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - K L M Coene
- Laboratory of Clinical Chemistry and Hematology, Máxima Medical Centre, Veldhoven, The Netherlands
| | - R Jahja
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, The Netherlands
| | - S J L Bakker
- Department of Internal Medicine, University of Groningen, University Medical Center Groningen, The Netherlands
| | - S C J Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, The Netherlands
| | - R A Wevers
- Department of Human Genetics, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - M R Heiner-Fokkema
- Department of Laboratory Medicine, Laboratory of Metabolic Diseases, University of Groningen, University Medical Centre Groningen, The Netherlands
| | - F J van Spronsen
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, The Netherlands
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Delbreil P, Dhondt S, Kenaan El Rahbani RM, Banquy X, Mitchell JJ, Brambilla D. Current Advances and Material Innovations in the Search for Novel Treatments of Phenylketonuria. Adv Healthc Mater 2024:e2401353. [PMID: 38801163 DOI: 10.1002/adhm.202401353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/22/2024] [Indexed: 05/29/2024]
Abstract
Phenylketonuria (PKU) is a genetically inherited disease caused by a mutation of the gene encoding phenylalanine hydroxylase (PAH) and is the most common inborn error of amino acid metabolism. A deficiency of PAH leads to increased blood and brain levels of phenylalanine (Phe), which may cause permanent neurocognitive symptoms and developmental delays if untreated. Current management strategies for PKU consist of early detection through neonatal screening and implementation of a restrictive diet with minimal amounts of natural protein in combination with Phe-free supplements and low-protein foods to meet nutritional requirements. For milder forms of PKU, oral treatment with synthetic sapropterin (BH4), the cofactor of PAH, may improve metabolic control of Phe and allow for more natural protein to be included in the patient's diet. For more severe forms, daily injections of pegvaliase, a PEGylated variant of phenylalanine ammonia-lyase (PAL), may allow for normalization of blood Phe levels. However, the latter treatment has considerable drawbacks, notably a strong immunogenicity of the exogenous enzyme and the attached polymeric chains. Research for novel therapies of PKU makes use of innovative materials for drug delivery and state-of-the-art protein engineering techniques to develop treatments which are safer, more effective, and potentially permanent.
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Affiliation(s)
- Philippe Delbreil
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | - Sofie Dhondt
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | | | - Xavier Banquy
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | - John J Mitchell
- Department of Pediatrics, Faculty of Medicine and Health Sciences, McGill University, Québec, H4A 3J1, Canada
| | - Davide Brambilla
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
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Trefz F, Frauendienst-Egger G, Dienel G, Cannet C, Schmidt-Mader B, Haas D, Blau N, Himmelreich N, Spraul M, Freisinger P, Dobrowolski S, Berg D, Pilotto A. Does hyperphenylalaninemia induce brain glucose hypometabolism? Cerebral spinal fluid findings in treated adult phenylketonuric patients. Mol Genet Metab 2024; 142:108464. [PMID: 38537426 DOI: 10.1016/j.ymgme.2024.108464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 05/08/2024]
Abstract
Despite numerous studies in human patients and animal models for phenylketonuria (PKU; OMIM#261600), the pathophysiology of PKU and the underlying causes of brain dysfunction and cognitive problems in PKU patients are not well understood. In this study, lumbar cerebral spinal fluid (CSF) was obtained immediately after blood sampling from early-treated adult PKU patients who had fasted overnight. Metabolite and amino acid concentrations in the CSF of PKU patients were compared with those of non-PKU controls. The CSF concentrations and CSF/plasma ratios for glucose and lactate were found to be below normal, similar to what has been reported for glucose transporter1 (GLUT1) deficiency patients who exhibit many of the same clinical symptoms as untreated PKU patients. CSF glucose and lactate levels were negatively correlated with CSF phenylalanine (Phe), while CSF glutamine and glutamate levels were positively correlated with CSF Phe levels. Plasma glucose levels were negatively correlated with plasma Phe concentrations in PKU subjects, which partly explains the reduced CSF glucose concentrations. Although brain glucose concentrations are unlikely to be low enough to impair brain glucose utilization, it is possible that the metabolism of Phe in the brain to produce phenyllactate, which can be transported across the blood-brain barrier to the blood, may consume glucose and/or lactate to generate the carbon backbone for glutamate. This glutamate is then converted to glutamine and carries the Phe-derived ammonia from the brain to the blood. While this mechanism remains to be tested, it may explain the correlations of CSF glutamine, glucose, and lactate concentrations with CSF Phe.
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Affiliation(s)
- Friedrich Trefz
- Heidelberg University, Medical Faculty of Heidelberg, Center for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg, Germany.
| | | | - Gerald Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | | | - Brigitte Schmidt-Mader
- Heidelberg University, Medical Faculty of Heidelberg, Center for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg, Germany
| | - Dorothea Haas
- Heidelberg University, Medical Faculty of Heidelberg, Center for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg, Germany
| | - Nenad Blau
- University Children's Hospital Zürich, Zürich, Switzerland
| | | | | | - Peter Freisinger
- Klinikum Reutlingen, Department of Pediatrics, Reutlingen, Germany
| | - Steven Dobrowolski
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15224, United States
| | - Daniela Berg
- Department of Neurology, University Hospital of Schleswig-Holstein, Kiel, Germany
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Carling RS, Barclay Z, Cantley N, Emmett EC, Hogg SL, Finezilber Y, Schulenburg‐Brand D, Murphy E, Moat SJ. Investigation of the relationship between phenylalanine in venous plasma and capillary blood using volumetric blood collection devices. JIMD Rep 2023; 64:468-476. [PMID: 37927487 PMCID: PMC10623100 DOI: 10.1002/jmd2.12398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/27/2023] [Accepted: 10/02/2023] [Indexed: 11/07/2023] Open
Abstract
Measurement of plasma and dried blood spot (DBS) phenylalanine (Phe) is key to monitoring patients with phenylketonuria (PKU). The relationship between plasma and capillary DBS Phe concentrations has been investigated previously, however, differences in methodology, calibration approach and assumptions about the volume of blood in a DBS sub-punch has complicated this. Volumetric blood collection devices (VBCDs) provide an opportunity to re-evaluate this relationship. Paired venous and capillary samples were collected from patients with PKU (n = 51). Capillary blood was collected onto both conventional newborn screening (NBS) cards and VBCDs. Specimens were analysed by liquid-chromatography tandem mass-spectrometry (LC-MS/MS) using a common calibrator. Use of VBCDs was evaluated qualitatively by patients. Mean bias between plasma and volumetrically collected capillary DBS Phe was -13%. Mean recovery (SD) of Phe from DBS was 89.4% (4.6). VBCDs confirmed that the volume of blood typically assumed to be present in a 3.2 mm sub-punch is over-estimated by 9.7%. Determination of the relationship between plasma and capillary DBS Phe, using a single analytical method, common calibration and VBCDs, demonstrated that once the under-recovery of Phe from DBS has been taken into account, there is no significant difference in the concentration of Phe in plasma and capillary blood. Conversely, comparison of plasma Phe with capillary DBS Phe collected on a NBS card highlighted the limitations of this approach. Introducing VBCDs for the routine monitoring of patients with PKU would provide a simple, acceptable specimen collection technique that ensures consistent sample quality and produces accurate and precise blood Phe results which are interchangeable with plasma Phe.
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Affiliation(s)
- Rachel S. Carling
- GKT School Medical EducationKings College LondonLondonUK
- Biochemical Sciences, Synnovis, Guys & St Thomas' NHSFTLondonUK
| | - Zoe Barclay
- Biochemical Sciences, Synnovis, Guys & St Thomas' NHSFTLondonUK
| | - Nathan Cantley
- Department of Clinical Biochemistry, Severn PathologySouthmead Hospital, North Bristol NHS TrustBristolUK
| | - Erin C. Emmett
- Biochemical Sciences, Synnovis, Guys & St Thomas' NHSFTLondonUK
| | - Sarah L. Hogg
- Biochemical Genetics UnitCambridge University HospitalsCambridgeUK
| | - Yael Finezilber
- Charles Dent Metabolic UnitNational Hospital for Neurology and Neurosurgery, Queen SquareLondonUK
| | - Danja Schulenburg‐Brand
- Department of Haematology, Immunology and Metabolic MedicineUniversity Hospital WalesCardiffUK
| | - Elaine Murphy
- Charles Dent Metabolic UnitNational Hospital for Neurology and Neurosurgery, Queen SquareLondonUK
| | - Stuart J. Moat
- Department of Medical Biochemistry, Immunology & ToxicologyUniversity Hospital WalesCardiffUK
- School of MedicineCardiff University, University Hospital WalesCardiffUK
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Parolisi S, Montanari C, Borghi E, Cazzorla C, Zuvadelli J, Tosi M, Barone R, Bensi G, Bonfanti C, Dionisi Vici C, Biasucci G, Burlina A, Carbone MT, Verduci E. Possible role of tryptophan metabolism along the microbiota-gut-brain axis on cognitive & behavioral aspects in Phenylketonuria. Pharmacol Res 2023; 197:106952. [PMID: 37804926 DOI: 10.1016/j.phrs.2023.106952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 10/09/2023]
Abstract
Cognitive and psychiatric disorders are well documented across the lifetime of patients with inborn errors of metabolism (IEMs). Gut microbiota impacts behavior and cognitive functions through the gut-brain axis (GBA). According to recent research, a broad spectrum of GBA disorders may be influenced by a perturbed Tryptophan (Trp) metabolism and are associated with alterations in composition or function of the gut microbiota. Furthermore, early-life diets may influence children's neurodevelopment and cognitive deficits in adulthood. In Phenylketonuria (PKU), since the main therapeutic intervention is based on a life-long restrictive diet, important alterations of gut microbiota have been observed. Studies on PKU highlight the impact of alterations of gut microbiota on the central nervous system (CNS), also investigating the involvement of metabolic pathways, such as Trp and kynurenine (KYN) metabolisms, involved in numerous neurodegenerative disorders. An alteration of Trp metabolism with an imbalance of the KYN pathway towards the production of neurotoxic metabolites implicated in numerous neurodegenerative and inflammatory diseases has been observed in PKU patients supplemented with Phe-free amino acid medical foods (AA-MF). The present review investigates the possible link between gut microbiota and the brain in IEMs, focusing on Trp metabolism in PKU. Considering the evidence collected, cognitive and behavioral well-being should always be monitored in routine IEMs clinical management. Further studies are required to evaluate the possible impact of Trp metabolism, through gut microbiota, on cognitive and behavioral functions in IEMs, to identify innovative dietetic strategies and improve quality of life and mental health of these patients.
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Affiliation(s)
- Sara Parolisi
- UOSD Metabolic Diseases, AORN Santobono-Pausilipon, Naples, Italy
| | - Chiara Montanari
- Department of Pediatrics, Vittore Buzzi Children's Hospital, University of Milan, Milan, Italy; Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| | - Elisa Borghi
- Department of Health Science, University of Milan, Milan, Italy
| | - Chiara Cazzorla
- Division of Inherited Metabolic Diseases, DIDAS Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Juri Zuvadelli
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, Milan, Italy
| | - Martina Tosi
- Department of Pediatrics, Vittore Buzzi Children's Hospital, University of Milan, Milan, Italy; Department of Health Science, University of Milan, Milan, Italy
| | - Rita Barone
- Child Neuropsychiatry Unit, Department of Clinical and Experimental Medicine, AOU Policlinico "G.Rodolico-San Marco", University of Catania, Catania, Italy
| | - Giulia Bensi
- Paediatrics & Neonatology Unit, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | - Cristina Bonfanti
- Rare metabolic disease unit, Pediatric Department, San Gerardo Hospital, Monza, Italy
| | | | - Giacomo Biasucci
- Paediatrics & Neonatology Unit, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | - Alberto Burlina
- Division of Inherited Metabolic Diseases, DIDAS Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Maria T Carbone
- UOSD Metabolic Diseases, AORN Santobono-Pausilipon, Naples, Italy
| | - Elvira Verduci
- Department of Pediatrics, Vittore Buzzi Children's Hospital, University of Milan, Milan, Italy; Department of Health Science, University of Milan, Milan, Italy.
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Christ SE, Clocksin HE, Zalik M, Goodlett BD, Sacharow SJ, Abbene EE. Neuropsychological assessment of adults with phenylketonuria using the NIH toolbox. Mol Genet Metab 2023; 139:107579. [PMID: 37099821 DOI: 10.1016/j.ymgme.2023.107579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/28/2023]
Abstract
Among researchers and clinicians, there is a call for the development and validation of new measures to better assess and characterize neurocognitive difficulties associated with early-treated phenylketonuria (ETPKU) and other metabolic disorders. The NIH Toolbox represents a relatively new computer-administered assessment tool and provides a sampling of performance across multiple cognitive domains, several of which (e.g., executive function, processing speed) are at risk for disruption in ETPKU. The goal of the present study was to provide an initial evaluation of the value and sensitivity of the NIH Toolbox for use with individuals with ETPKU. To this end, a sample of adults with ETPKU and a demographically-matched comparison group without PKU completed the cognitive and motor batteries of the Toolbox. Results indicate that overall performance (as reflected by the Fluid Cognition Composite) was sensitive to both group differences (ETPKU vs non-PKU) as well as blood Phe levels (a marker of metabolic control). The present findings offer preliminary support for the utility of the NIH Toolbox as a measure of neurocognitive functioning in individuals with ETPKU. Future research including a larger sample size and broader age range is needed to fully validate the Toolbox for clinical and research use with individuals with ETPKU.
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Affiliation(s)
- Shawn E Christ
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA.
| | - Hayley E Clocksin
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Maia Zalik
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
| | | | - Stephanie J Sacharow
- Boston Children's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Emily E Abbene
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
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Bregalda A, Carducci C, Viscomi MT, Pierigè F, Biagiotti S, Menotta M, Biancucci F, Pascucci T, Leuzzi V, Magnani M, Rossi L. Myelin basic protein recovery during PKU mice lifespan and the potential role of microRNAs on its regulation. Neurobiol Dis 2023; 180:106093. [PMID: 36948260 DOI: 10.1016/j.nbd.2023.106093] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/10/2023] [Accepted: 03/17/2023] [Indexed: 03/24/2023] Open
Abstract
Untreated phenylketonuria (PKU) patients and PKU animal models show hypomyelination in the central nervous system and white matter damages, which are accompanied by myelin basic protein (MBP) impairment. Despite many assumptions, the primary explanation of the mentioned cerebral outcomes remains elusive. In this study, MBP protein and mRNA expression on brains of wild type (WT) and phenylketonuric (ENU2) mice were analyzed throughout mice lifespan (14-60-180-270-360-540 post-natal days, PND). The results confirmed the low MBP expression at first PND times, while revealed an unprecedented progressive MBP protein expression recovery in aged ENU2 mice. Unexpectedly, unaltered MBP mRNA expression between WT and ENU2 was always observed. Additionally, for the same time intervals, a significant decrease of the phenylalanine concentration in the peripheral blood and brain of ENU2 mice was detected, to date, for the first time. In this scenario, a translational hindrance of MBP during initial and late cerebral development in ENU2 mice was hypothesized, leading to the execution of a microRNA microarray analysis on 60 PND brains, which was followed by a proteomic assay on 60 and 360 PND brains in order to validate in silico miRNA-target predictions. Taken together, miR-218 - 1-3p, miR - 1231-3p and miR-217-5p were considered as the most impactful microRNAs, since a downregulation of their potential targets (MAG, CNTNAP2 and ANLN, respectively) can indirectly lead to a low MBP protein expression. These miRNAs, in addition, follow an opposite expression trend compared to MBP during adulthood, and their target proteins revealed a complete normalization in aged ENU2 mice. In conclusion, these results provide a new perspective on the PKU pathophysiology understanding and on a possible treatment, emphasizing the potential modulating role of differentially expressed microRNAs in MBP expression on PKU brains during PKU mouse lifespan.
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Affiliation(s)
- Alessandro Bregalda
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy.
| | - Claudia Carducci
- Department of Experimental Medicine, Sapienza University, viale del Policlinico 155, 00161 Rome, Italy
| | - Maria Teresa Viscomi
- Department of Life Sciences and Public Health, Sect. Histology and Embryology, Università Cattolica del S. Cuore, Largo F. Vito 1, 00168 Rome, Italy; Fondazione Policlinico Universitario "Agostino Gemelli", IRCCS, 00168 Rome, Italy
| | - Francesca Pierigè
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Sara Biagiotti
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Michele Menotta
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Federica Biancucci
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Tiziana Pascucci
- Fondazione Santa Lucia IRCCS, via Ardeatina 306, 00142 Rome, Italy; Department of Psychology and Centro "Daniel Bovet", Sapienza University, via dei Marsi 78, 00185 Rome, Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Sapienza University, via dei Sabelli 108, 00185 Rome, Italy
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso, Milan, Italy
| | - Luigia Rossi
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso, Milan, Italy
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Chen A, Pan Y, Chen J. Clinical, genetic, and experimental research of hyperphenylalaninemia. Front Genet 2023; 13:1051153. [PMID: 36685931 PMCID: PMC9845280 DOI: 10.3389/fgene.2022.1051153] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/06/2022] [Indexed: 01/06/2023] Open
Abstract
Hyperphenylalaninemia (HPA) is the most common amino acid metabolism defect in humans. It is an autosomal-recessive disorder of the phenylalanine (Phe) metabolism, in which high Phe concentrations and low tyrosine (Tyr) concentrations in the blood cause phenylketonuria (PKU), brain dysfunction, light pigmentation and musty odor. Newborn screening data of HPA have revealed that the prevalence varies worldwide, with an average of 1:10,000. Most cases of HPA result from phenylalanine hydroxylase (PAH) deficiency, while a small number of HPA are caused by defects in the tetrahydrobiopterin (BH4) metabolism and DnaJ heat shock protein family (Hsp40) member C12 (DNAJC12) deficiency. Currently, the molecular pathophysiology of the neuropathology associated with HPA remains incompletely understood. Dietary restriction of Phe has been highly successful, although outcomes are still suboptimal and patients find it difficult to adhere to the treatment. Pharmacological treatments, such as BH4 and phenylalanine ammonia lyase, are available. Gene therapy for HPA is still in development.
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Affiliation(s)
- Anqi Chen
- Department of Forensic Medicine, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yukun Pan
- Barbell Therapeutics Co. Ltd., Shanghai, China,*Correspondence: Yukun Pan, ; Jinzhong Chen,
| | - Jinzhong Chen
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China,*Correspondence: Yukun Pan, ; Jinzhong Chen,
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10
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Shegani A, Kealey S, Luzi F, Basagni F, Machado JDM, Ekici SD, Ferocino A, Gee AD, Bongarzone S. Radiosynthesis, Preclinical, and Clinical Positron Emission Tomography Studies of Carbon-11 Labeled Endogenous and Natural Exogenous Compounds. Chem Rev 2022; 123:105-229. [PMID: 36399832 PMCID: PMC9837829 DOI: 10.1021/acs.chemrev.2c00398] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The presence of positron emission tomography (PET) centers at most major hospitals worldwide, along with the improvement of PET scanner sensitivity and the introduction of total body PET systems, has increased the interest in the PET tracer development using the short-lived radionuclides carbon-11. In the last few decades, methodological improvements and fully automated modules have allowed the development of carbon-11 tracers for clinical use. Radiolabeling natural compounds with carbon-11 by substituting one of the backbone carbons with the radionuclide has provided important information on the biochemistry of the authentic compounds and increased the understanding of their in vivo behavior in healthy and diseased states. The number of endogenous and natural compounds essential for human life is staggering, ranging from simple alcohols to vitamins and peptides. This review collates all the carbon-11 radiolabeled endogenous and natural exogenous compounds synthesised to date, including essential information on their radiochemistry methodologies and preclinical and clinical studies in healthy subjects.
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Affiliation(s)
- Antonio Shegani
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Steven Kealey
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Federico Luzi
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Filippo Basagni
- Department
of Pharmacy and Biotechnology, Alma Mater
Studiorum−University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Joana do Mar Machado
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Sevban Doğan Ekici
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Alessandra Ferocino
- Institute
of Organic Synthesis and Photoreactivity, Italian National Research Council, via Piero Gobetti 101, 40129 Bologna, Italy
| | - Antony D. Gee
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom,A.G.: email,
| | - Salvatore Bongarzone
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom,S.B.:
email,
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11
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Becsei D, Kiss E, Szatmári I, Arató A, Reusz G, Szabó AJ, Bókay J, Zsidegh P. A retrospective analysis of metabolic control in children with PKU in the COVID-19 era. Mol Genet Metab Rep 2022; 32:100897. [PMID: 35845719 PMCID: PMC9284369 DOI: 10.1016/j.ymgmr.2022.100897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 11/30/2022] Open
Abstract
Background Patients with phenylketonuria (PKU) must maintain a lifelong natural protein-restricted diet to prevent neuro-cognitive damage. Early diagnosis is established with newborn screening, with diet subsequently controlled by regular phenylalanine (Phe) monitoring. During the COVID-19 pandemic, significant lockdown measures were introduced that may have influenced the above. Aim of our study To establish whether the diagnosis was delayed in neonates during the pandemic. In addition, metabolic control was further assessed during the COVID-19 pandemic era (CE) compared to the same period a year prior (non-COVID-19 era, NCE). The lockdown periods (LD) were also compared with unrestricted periods (URP). Patients, methods Six neonates born during the CE and eight neonates born during NCE were included in the newborn screening analysis. Seventy-two classical PKU patients aged 2–18 years and categorized as children (2–12 years; 51 patients) and adolescents (>13 years; 21 patients) were included in the metabolic control analysis. The frequency of dried blood spot (DBS) sampling and Phe levels were assessed according to the different periods. Results There was no diagnostic or therapeutic delay in reaching the recommended Phe range in neonates born during CE compared to those born in NCE (median [interquartile range, IQR]: 23.5 [22.5–24] vs. 22 [18.0–27] days, p = NS). The cumulative DBS sampling frequency in children increased by 9.9% in the CE while no change was noted in the adolescent group. The median Phe level increased significantly in both age groups in the CE, but remained within the recommended target range. During CE, changes in Phe levels differed in the two age groups: children had the highest median Phe in the second lockdown period (LD2), while the adolescents had an increased Phe in URP. There were significant negative correlations between DBS sampling frequencies and Phe levels in both age groups in NCE (children: r − 0.43, p = 0.002; adolescents r = −0.37, p = 0.012), and in adolescents in CE (r = −0.62, p = 0.006). Conclusion The pandemic did not impact newborn metabolic screening. The increased frequency of DBS sampling in CE and good target Phe levels suggest a better compliance in a very sensitive period. Since many factors may impact metabolic control in the different age groups, further studies are needed to analyse their respective role.
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Key Words
- CE, COVID-19 era
- CLD1, control to lockdown period 1
- CLD2, control to lockdown period 2
- COVID, coronavirus disease
- COVID-19 pandemic
- CURP, control to unrestricted period
- DBS, dried blood spot
- IQR, interquartile range
- LD, lockdown
- Lockdown
- MS/MS, tandem mass spectrometry
- Metabolic control
- NCE, non-COVID-19 era
- Phenylketonuria
- SARS, Severe Acute Respiratory Syndrome,
- URP, unrestricted period
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Affiliation(s)
- Dóra Becsei
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - Erika Kiss
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - Ildikó Szatmári
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - András Arató
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - György Reusz
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - Attila J Szabó
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary.,ELKH-SE Pediatrics and Nephrology Research Group, Budapest, Hungary
| | - János Bókay
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
| | - Petra Zsidegh
- 1st Department of Pediatrics, Semmelweis University, Bókay János u. 53-54, Budapest 1083, Hungary
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12
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Dobrowolski SF, Phua YL, Vockley J, Goetzman E, Blair HC. Phenylketonuria oxidative stress and energy dysregulation: Emerging pathophysiological elements provide interventional opportunity. Mol Genet Metab 2022; 136:111-117. [PMID: 35379539 PMCID: PMC9832337 DOI: 10.1016/j.ymgme.2022.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 01/13/2023]
Abstract
Phenylalanine hydroxylase (PAH) deficient phenylketonuria (PKU) is rightfully considered the paradigm treatable metabolic disease. Dietary substrate restriction (i.e. phenylalanine (Phe) restriction) was applied >60 years ago and remains the primary PKU management means. The traditional model of PKU neuropathophysiology dictates blood Phe over-representation directs asymmetric blood:brain barrier amino acid transport through the LAT1 transporter with subsequent increased cerebral Phe concentration and low concentrations of tyrosine (Tyr), tryptophan (Trp), leucine (Leu), valine (Val), and isoleucine (Ile). Low Tyr and Trp concentrations generate secondary serotonergic and dopaminergic neurotransmitter paucities, widely attributed as drivers of PKU neurologic phenotypes. White matter disease, a central PKU characteristic, is ascribed to Phe-mediated tissue toxicity. Impaired cerebral protein synthesis, by reduced concentrations of non-Phe large neutral amino acids, is another cited pathological mechanism. The PKU amino acid transport model suggests Phe management should be more efficacious than is realized, as even early identified, continuously treated patients that retain therapy compliance into adulthood, demonstrate neurologic disease elements. Reduced cerebral metabolism was an early-recognized element of PKU pathology. Legacy data (late 1960's to mid-1970's) determined the Phe catabolite phenylpyruvate inhibits mitochondrial pyruvate transport. Respirometry of Pahenu2 cerebral mitochondria have attenuated respiratory chain complex 1 induction in response to pyruvate substrate, indicating reduced energy metabolism. Oxidative stress is intrinsic to PKU and Pahenu2 brain tissue presents increased reactive oxygen species. Phenylpyruvate inhibits glucose-6-phosphate dehydrogenase that generates reduced niacinamide adenine dinucleotide phosphate the obligatory cofactor of glutathione reductase. Pahenu2 brain tissue metabolomics identified increased oxidized glutathione and glutathione disulfide. Over-represented glutathione disulfide argues for reduced glutathione reductase activity secondary to reduced NADPH. Herein, we review evidence of energy and oxidative stress involvement in PKU pathology. Data suggests energy deficit and oxidative stress are features of PKU pathophysiology, providing intervention-amenable therapeutic targets to ameliorate disease elements refractory to standard of care.
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Affiliation(s)
- Steven F Dobrowolski
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15224, United States of America.
| | - Yu Leng Phua
- Division of Medical Genetics, Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, United States of America
| | - Jerry Vockley
- Division of Medical Genetics, Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, United States of America
| | - Eric Goetzman
- Division of Medical Genetics, Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, United States of America
| | - Harry C Blair
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15224, United States of America; Veteran's Affairs Medical Center, Pittsburgh, PA, United States of America
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13
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Becsei D, Hiripi R, Kiss E, Szatmári I, Arató A, Reusz G, Szabó AJ, Bókay J, Zsidegh P. Quality of life in children living with PKU - a single-center, cross-sectional, observational study from Hungary. Mol Genet Metab Rep 2021; 29:100823. [PMID: 34900594 PMCID: PMC8639791 DOI: 10.1016/j.ymgmr.2021.100823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 11/12/2021] [Accepted: 11/13/2021] [Indexed: 11/26/2022] Open
Abstract
Background Phenylketonuria (PKU) is an inherited error of metabolism, screened at 48–72 h of life since 1975 in Hungary. The patients have to keep a strict lifelong protein-restricted diet, resulting in PKU and its treatment can lead to social and financial burdens. The current study aimed to evaluate the health-related quality of life (HRQoL) of children living with PKU. Patients and methods A single-centre, cross-sectional, observational study was conducted at the Center of Newborn Screening and Inherited Metabolic Disorders of Budapest, Hungary, using the PKU-quality of life (PKU-QoL) questionnaire. Responses of 59 parents and 11 teenagers were collected. Numerous aspects regarding HRQoL were analysed according to clinical compliance and severity. The patients were classified into groups with good or suboptimal adherence based on regular phenylalanine (Phe) values. The online officially translated versions of the adolescent or parental PKU-QoL questionnaire were used and analysed anonymously. Differences in HRQoL were compared - PKU vs. Hyperphenylalaninaemia (HPA) and good vs. suboptimal adherence. Results Twenty-five of 32 examined parameters had no or little impact on HRQoL. The most frequently reported symptom was irritability. Food enjoyment was the most impacted domain, with a major severity score in the adolescent group (median 62,5, IQR: 25–75). The emotional impact was scored at moderate severity by both the adolescents and parents. Classical PKU patients with good metabolic control were more frequently tired than HPA patients (0,0027). The group with poor metabolic adherence showed more frequent tiredness (p = 0,03), slow thinking (p = 0,018) and anxiety (p = 0,015). Conclusion Overall, our patients showed an excellent HRQoL; most domains (29/36) were reported as little/no impacted. Worse QoL was found in patients with suboptimal metabolic control. Particular attention should be paid to the emotional health of PKU patients.
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Key Words
- Children
- DBS, dried blood spot
- DPR, dietary protein restriction
- GMP, glycomacropeptide
- HPA, hyperphenylalaninaemia
- HRQoL
- HRQoL, health-related quality of life
- Health-related quality of life
- IQ, intelligence quotient
- IQR, interquartile range
- PAH, phenylalanine hydroxylase
- PKU
- PKU, phenylketonuria
- Parents
- Phenylketonuria
- QoL, quality of life,
- SD, standard deviation
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Affiliation(s)
- Dóra Becsei
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - Réka Hiripi
- Faculty of Medicine, Semmelweis University, Üllői út 26, Budapest 1085, Hungary
| | - Erika Kiss
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - Ildiko Szatmári
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - András Arató
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - György Reusz
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - Attila J Szabó
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary.,ELKH-SE Pediatrics and Nephrology Research Group, Budapest, Hungary
| | - János Bókay
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
| | - Petra Zsidegh
- 1st Department of Pediatrics, Semmelweis University, Bókay J. u. 53-54, Budapest 1083, Hungary
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14
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Bernstein L, Hansen J, Kogelmann C, Ellerbrok M, Giżewska M, Gaughan S, Rocha JC, Belanger-Quintana A, Rohr F. Normalizing Diet in Individuals with Phenylketonuria Treated with Pegvaliase: A Case Series and Patient Perspective. NUTRITION AND DIETARY SUPPLEMENTS 2021. [DOI: 10.2147/nds.s337135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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15
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Tanacli R, Hassel JH, Gebker R, Berger A, Gräfe M, Schneeweis C, Doeblin P, Fleck E, Stehning C, Tacke F, Pieske B, Spranger J, Plöckinger U, Ziagaki A, Kelle S. Cardiac Magnetic Resonance Reveals Incipient Cardiomyopathy Traits in Adult Patients With Phenylketonuria. J Am Heart Assoc 2021; 10:e020351. [PMID: 34423658 PMCID: PMC8649272 DOI: 10.1161/jaha.120.020351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Phenylketonuria is the most common inborn error of amino acid metabolism, where oxidative stress and collateral metabolic abnormalities are likely to cause cardiac structural and functional modifications. We aim herein to characterize the cardiac phenotype of adult subjects with phenylketonuria using advanced cardiac imaging. Methods and Results Thirty-nine adult patients with phenylketonuria (age, 30.5±8.7 years; 10-year mean phenylalanine concentration, 924±330 µmol/L) and 39 age- and sex-matched healthy controls were investigated. Participants underwent a comprehensive cardiac magnetic resonance and echocardiography examination. Ten-year mean plasma levels of phenylalanine and tyrosine were used to quantify disease activity and adherence to treatment. Patients with phenylketonuria had thinner left ventricular walls (septal end-diastolic thickness, 7.0±17 versus 8.8±1.7 mm [P<0.001]; lateral thickness, 6.1±1.4 versus 6.8±1.2 mm [P=0.004]), more dilated left ventricular cavity (end-diastolic volume, 87±14 versus 80±14 mL/m2 [P=0.0178]; end-systolic volume, 36±9 versus 29±8 mL/m2 [P<0.001]), lower ejection fraction (59±6% versus 64±6% [P<0.001]), reduced systolic deformation (global circumferential strain, -29.9±4.2 % versus -32.2±5.0 % [P=0.027]), and lower left ventricular mass (38.2±7.9 versus 47.8±11.0 g/m2 [P<0.001]). T1 native values were decreased (936±53 versus 996±26 ms [P<0.001]), with particular low values in patients with phenylalanine >1200 µmol/L (909±48 ms). Both mean phenylalanine (P=0.013) and tyrosine (P=0.035) levels were independently correlated with T1; and in a multiple regression model, higher phenylalanine levels and higher left ventricular mass associate with lower T1. Conclusions Cardiac phenotype of adult patients with phenylketonuria reveals some traits of an early-stage cardiomyopathy. Regular cardiology follow-up, tighter therapeutic control, and prophylaxis of cardiovascular risk factors, in particular dyslipidemia, are recommended.
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Affiliation(s)
- Radu Tanacli
- Department of Cardiology German Heart Centre Berlin Berlin Germany.,Department of Cardiology Charité University Medicine Berlin Berlin Germany
| | | | - Rolf Gebker
- Department of Cardiology German Heart Centre Berlin Berlin Germany
| | - Alexander Berger
- Department of Cardiology German Heart Centre Berlin Berlin Germany
| | - Michael Gräfe
- Department of Cardiology German Heart Centre Berlin Berlin Germany
| | | | - Patrick Doeblin
- Department of Cardiology German Heart Centre Berlin Berlin Germany
| | - Eckart Fleck
- Department of Cardiology German Heart Centre Berlin Berlin Germany
| | | | - Frank Tacke
- Department of Hepatology and Gastroenterology Charité University Medicine Berlin Berlin Germany.,Interdisziplinäres Stoffwechsel-Centrum Charité-Universitätsmedizin BerlinCampus Virchow Klinikum Berlin Germany
| | - Burkert Pieske
- Department of Cardiology German Heart Centre Berlin Berlin Germany.,Department of Cardiology Charité University Medicine Berlin Berlin Germany.,German Centre for Cardiovascular Research DZHK, Partner Site Berlin Berlin Germany
| | - Joachim Spranger
- Department of Endocrinology, Diabetes, and Nutrition Charité University Medicine Berlin Berlin Germany.,Interdisziplinäres Stoffwechsel-Centrum Charité-Universitätsmedizin BerlinCampus Virchow Klinikum Berlin Germany
| | - Ursula Plöckinger
- Interdisziplinäres Stoffwechsel-Centrum Charité-Universitätsmedizin BerlinCampus Virchow Klinikum Berlin Germany
| | - Athanasia Ziagaki
- Interdisziplinäres Stoffwechsel-Centrum Charité-Universitätsmedizin BerlinCampus Virchow Klinikum Berlin Germany
| | - Sebastian Kelle
- Department of Cardiology German Heart Centre Berlin Berlin Germany.,Department of Cardiology Charité University Medicine Berlin Berlin Germany.,German Centre for Cardiovascular Research DZHK, Partner Site Berlin Berlin Germany
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16
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Abstract
Phenylketonuria (PKU; also known as phenylalanine hydroxylase (PAH) deficiency) is an autosomal recessive disorder of phenylalanine metabolism, in which especially high phenylalanine concentrations cause brain dysfunction. If untreated, this brain dysfunction results in severe intellectual disability, epilepsy and behavioural problems. The prevalence varies worldwide, with an average of about 1:10,000 newborns. Early diagnosis is based on newborn screening, and if treatment is started early and continued, intelligence is within normal limits with, on average, some suboptimal neurocognitive function. Dietary restriction of phenylalanine has been the mainstay of treatment for over 60 years and has been highly successful, although outcomes are still suboptimal and patients can find the treatment difficult to adhere to. Pharmacological treatments are available, such as tetrahydrobiopterin, which is effective in only a minority of patients (usually those with milder PKU), and pegylated phenylalanine ammonia lyase, which requires daily subcutaneous injections and causes adverse immune responses. Given the drawbacks of these approaches, other treatments are in development, such as mRNA and gene therapy. Even though PAH deficiency is the most common defect of amino acid metabolism in humans, brain dysfunction in individuals with PKU is still not well understood and further research is needed to facilitate development of pathophysiology-driven treatments.
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Affiliation(s)
- Francjan J van Spronsen
- Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands.
| | - Nenad Blau
- University Children's Hospital in Zurich, Zurich, Switzerland
| | - Cary Harding
- Department of Molecular and Medical Genetics and Department of Pediatrics, Oregon Health & Science University, Oregon, USA
| | | | - Nicola Longo
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA
| | - Annet M Bosch
- University of Amsterdam, Department of Pediatrics, Division of Metabolic Disorders, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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17
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van Wegberg A, Evers R, Burgerhof J, van Dam E, Heiner-Fokkema MR, Janssen M, de Vries MC, van Spronsen FJ. Effect of BH4 on blood phenylalanine and tyrosine variations in patients with phenylketonuria. Mol Genet Metab 2021; 133:49-55. [PMID: 33766497 DOI: 10.1016/j.ymgme.2021.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/26/2021] [Accepted: 02/26/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND In patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations. METHODS Blood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV). RESULTS BH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher. CONCLUSION BH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis.
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Affiliation(s)
- Amj van Wegberg
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Raf Evers
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Jgm Burgerhof
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - E van Dam
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, the Netherlands
| | - M R Heiner-Fokkema
- Department of Laboratory Medicine, Laboratory of Metabolic Diseases, University of Groningen, University Medical Centre Groningen, the Netherlands
| | - McH Janssen
- Department of Internal Medicine, Radboudumc, Nijmegen, the Netherlands
| | - M C de Vries
- Department of Pediatrics, Radboudumc Nijmegen, the Netherlands
| | - F J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, the Netherlands.
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18
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Burgess NM, Kelso W, Malpas CB, Winton-Brown T, Fazio T, Panetta J, De Jong G, Neath J, Atherton S, Velakoulis D, Walterfang M. The effect of improved dietary control on cognitive and psychiatric functioning in adults with phenylketonuria: the ReDAPT study. Orphanet J Rare Dis 2021; 16:35. [PMID: 33461585 PMCID: PMC7814424 DOI: 10.1186/s13023-020-01668-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
Background Phenylketonuria (PKU) is an autosomal recessive inherited disorder characterised by a deficiency in phenylalanine hydroxylase. Untreated, PKU is associated with a wide range of cognitive and psychiatric sequelae. Contemporary management guidelines recommend lifetime dietary control of phenylalanine (Phe) levels, however many individuals who discontinue dietary control subsequently suffer symptoms of anxiety, depression and disturbances to cognition. We undertook a prospective cohort study of patients with early-treated phenylketonuria who had ceased dietary control to test the hypothesis that resumption of dietary control of PKU is associated with improvements in measures of psychiatric morbidity and cognitive functioning. Methods We re-initiated dietary control for early-treated patients with PKU and monitored cognitive and psychiatric outcomes over a twelve-month period. Assessments included objective cognitive function (measured by cognitive proficiency index (CPI)), anxiety and depression scales. General linear mixed model (GLMM) analyses were performed to assess change in psychometric variables from baseline over twelve months after resumption of dietary control. Results A total of nine patients were recruited. Mean age was 33 years (SD = 8.75), five were female. Mean time off dietary control was 19.1 years (SD = 11.3), and mean baseline phenylalanine (Phe) levels were 1108 µmol/L (SD = 293). GLMM analysis demonstrated a positive relationship between CPI and time on diet (b = 0.56 [95% CI = 0.17, 0.95]). Age, time off diet, Phe levels and depression scores were not associated with cognitive function. There was a negative relationship between time on diet and anxiety (b = − 0.88 95% CI = [− 1.26, − 0.50]) and depression ratings (b = − 0.61, 95% CI = [− 0.95, − 0.26]). Conclusions This study demonstrated improvements in cognitive function, anxiety, and depression ratings associated with resumption of dietary control of PKU. Raw Phe levels were not strongly associated with psychiatric or cognitive scores in this cohort. These findings support the importance of lifelong treatment for PKU in improving the cognitive and psychiatric sequelae of the disease.
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Affiliation(s)
- Nicholas M Burgess
- Neuropsychiatry Unit, Royal Melbourne Hospital, Level 2, John Cade Building, Melbourne,, 3050, Australia
| | - Wendy Kelso
- Neuropsychiatry Unit, Royal Melbourne Hospital, Level 2, John Cade Building, Melbourne,, 3050, Australia
| | - Charles B Malpas
- Department of Neurology, Royal Melbourne Hospital, Melbourne, Australia.,Clinical Outcomes Research Unit (CORe), Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia.,Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Toby Winton-Brown
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Timothy Fazio
- Department of Metabolic Medicine, Royal Melbourne Hospital, Melbourne, Australia.,Melbourne Medical School, Department of Medicine and Radiology, University of Melbourne, Parkville, Australia
| | - Julie Panetta
- Department of Metabolic Medicine, Royal Melbourne Hospital, Melbourne, Australia
| | - Gerard De Jong
- Department of Metabolic Medicine, Royal Melbourne Hospital, Melbourne, Australia
| | - Joanna Neath
- Neuropsychiatry Unit, Royal Melbourne Hospital, Level 2, John Cade Building, Melbourne,, 3050, Australia
| | | | - Dennis Velakoulis
- Neuropsychiatry Unit, Royal Melbourne Hospital, Level 2, John Cade Building, Melbourne,, 3050, Australia.,Melbourne Neuropsychiatry Centre, University of Melbourne and North-Western Mental Health, Melbourne, Australia
| | - Mark Walterfang
- Neuropsychiatry Unit, Royal Melbourne Hospital, Level 2, John Cade Building, Melbourne,, 3050, Australia. .,Melbourne Neuropsychiatry Centre, University of Melbourne and North-Western Mental Health, Melbourne, Australia. .,Florey Institute of Neuroscience and Mental Health, Melbourne, Australia.
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19
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Energy metabolism profile of the effects of amino acid treatment on hepatocytes: Phenylalanine and phenylpyruvate inhibit glycolysis of hepatocytes. Nutrition 2020; 82:111042. [PMID: 33246675 DOI: 10.1016/j.nut.2020.111042] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 08/06/2020] [Accepted: 10/08/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Amino acids are not only the building blocks of proteins, but also can be metabolized to energy substances or function as signaling molecules. The aim of this study was to profile whether amino acid treatment (essential amino acids and alanine) affects the energy metabolism (glycolysis, mitochondrial respiration) of cultured hepatocytes. METHODS AML12 hepatocytes were treated with 5 mM of each amino acid for 1 h and the energy metabolism was then measured by using an extracellular flux analyzer. RESULTS The results showed that phenylalanine and lysine decreased the extracellular acidification rate (ECAR), an indirect indicator of glycolysis, whereas isoleucine and histidine increased the ECAR. Amino acids did not affect the oxygen consumption rate, an indirect indicator of mitochondrial respiration. The glycolysis stress test revealed that treatment of the hepatocytes with phenylalanine inhibited glycolysis when the concentration of the substrate for glycolysis was sufficient in cultured media. We also investigated the effect of metabolites derived from conversion of phenylalanine on glycolysis in hepatocytes and found that phenylpyruvate inhibited glycolysis, whereas tyrosine and phenylethylamine did not affect glycolysis. CONCLUSIONS The findings from the present study complement basic knowledge of the effects of amino acid treatment on energy metabolism in cultured hepatocytes and indicate that phenylalanine and phenylpyruvate inhibit glycolysis.
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20
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Daly A, Evans S, Pinto A, Ashmore C, Rocha JC, MacDonald A. A 3 Year Longitudinal Prospective Review Examining the Dietary Profile and Contribution Made by Special Low Protein Foods to Energy and Macronutrient Intake in Children with Phenylketonuria. Nutrients 2020; 12:E3153. [PMID: 33076399 PMCID: PMC7602523 DOI: 10.3390/nu12103153] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 10/11/2020] [Accepted: 10/12/2020] [Indexed: 12/18/2022] Open
Abstract
The nutritional composition of special low protein foods (SLPFs) is controlled under EU legislation for 'Foods for Special Medical Purposes (FSMP)'. They are designed to meet the energy needs of patients unable to eat a normal protein containing diet. In phenylketonuria (PKU), the macronutrient contribution of SLPFs has been inadequately examined. AIM A 3-year longitudinal prospective study investigating the contribution of SLPFs to the macronutrient intake of children with early treated PKU. METHODS 48 children (27 boys) with a mean recruitment age of 9.3 y were studied. Semi-quantitative dietary assessments and food frequency questionnaires (FFQ) were collected three to four times/year for 3 years. RESULTS The mean energy intake provided by SLPFs was 33% (SD ± 8), and this figure was 42% (SD ± 13) for normal food and 21% (SD ± 5) for protein substitutes (PS). SLPFs supplied a mean intake of 40% carbohydrate (SD ± 10), 51% starch (SD ± 18), 21% sugar (SD ± 8), and 38% fat (SD ± 13). Fibre intake met 83% of the Scientific Advisory Committee on Nutrition (SACN) reference value, with 50% coming from SLPFs with added gums and hydrocolloids. Low protein bread, pasta and milk provided the highest energy contribution, and the intake of sweet SLPFs (e.g., biscuits, cakes, and chocolate) was minimal. Children averaged three portions fruit/vegetable daily, and children aged ≥ 12 y had irregular meal patterns. CONCLUSION SLPFs provide essential energy in phenylalanine restricted diets. Optimising the nutritional quality of SLPFs deserves more attention.
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Affiliation(s)
- Anne Daly
- Dietetic Department, Birmingham Children’s Hospital, Steelhouse Lane, Birmingham B4 6NH, UK; (S.E.); (A.P.); (C.A.); (A.M.)
| | - Sharon Evans
- Dietetic Department, Birmingham Children’s Hospital, Steelhouse Lane, Birmingham B4 6NH, UK; (S.E.); (A.P.); (C.A.); (A.M.)
| | - Alex Pinto
- Dietetic Department, Birmingham Children’s Hospital, Steelhouse Lane, Birmingham B4 6NH, UK; (S.E.); (A.P.); (C.A.); (A.M.)
| | - Catherine Ashmore
- Dietetic Department, Birmingham Children’s Hospital, Steelhouse Lane, Birmingham B4 6NH, UK; (S.E.); (A.P.); (C.A.); (A.M.)
| | - Júlio César Rocha
- Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal;
- Centre for Health Technology and Services Research (CINTESIS), 4200-450 Porto, Portugal
| | - Anita MacDonald
- Dietetic Department, Birmingham Children’s Hospital, Steelhouse Lane, Birmingham B4 6NH, UK; (S.E.); (A.P.); (C.A.); (A.M.)
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21
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Ferreira BK, Rodrigues MT, Streck EL, Ferreira GC, Schuck PF. White matter disturbances in phenylketonuria: Possible underlying mechanisms. J Neurosci Res 2020; 99:349-360. [PMID: 32141105 DOI: 10.1002/jnr.24598] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/09/2020] [Accepted: 02/04/2020] [Indexed: 12/24/2022]
Abstract
White matter pathologies, as well as intellectual disability, microcephaly, and other central nervous system injuries, are clinical traits commonly ascribed to classic phenylketonuria (PKU). PKU is an inherited metabolic disease elicited by the deficiency of phenylalanine hydroxylase. Accumulation of l-phenylalanine (Phe) and its metabolites is found in tissues and body fluids in phenylketonuric patients. In order to mitigate the clinical findings, rigorous dietary Phe restriction constitutes the core of therapeutic management in PKU. Myelination is the process whereby the oligodendrocytes wrap myelin sheaths around the axons, supporting the conduction of action potentials. White matter injuries are implicated in the brain damage related to PKU, especially in untreated or poorly treated patients. The present review summarizes evidence toward putative mechanisms driving the white matter pathology in PKU patients.
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Affiliation(s)
- Bruna Klippel Ferreira
- Laboratório de Neuroenergética e Erros Inatos do Metabolismo, Programa de Bioquímica e Biofísica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Porto Alegre, Brazil
| | - Melissa Torres Rodrigues
- Laboratório de Erros Inatos do Metabolismo, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.,Programa de Pós-graduação em Biologia Celular e Molecular, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - Emilio Luiz Streck
- Laboratório de Neurologia Experimental, Programa de Pós-Graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, Brazil
| | - Gustavo Costa Ferreira
- Laboratório de Neuroenergética e Erros Inatos do Metabolismo, Programa de Bioquímica e Biofísica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Porto Alegre, Brazil
| | - Patricia Fernanda Schuck
- Laboratório de Erros Inatos do Metabolismo, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.,Programa de Pós-graduação em Biologia Celular e Molecular, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
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22
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Ashe K, Kelso W, Farrand S, Panetta J, Fazio T, De Jong G, Walterfang M. Psychiatric and Cognitive Aspects of Phenylketonuria: The Limitations of Diet and Promise of New Treatments. Front Psychiatry 2019; 10:561. [PMID: 31551819 PMCID: PMC6748028 DOI: 10.3389/fpsyt.2019.00561] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 07/17/2019] [Indexed: 12/30/2022] Open
Abstract
Phenylketonuria (PKU) is a recessive disorder of phenylalanine metabolism due to mutations in the gene for phenylalanine hydroxylase (PAH). Reduced PAH activity results in significant hyperphenylalaninemia, which leads to alterations in cerebral myelin and protein synthesis, as well as reduced levels of serotonin, dopamine, and noradrenaline in the brain. When untreated, brain development is grossly disrupted and significant intellectual impairment and behavioral disturbance occur. The advent of neonatal heel prick screening has allowed for diagnosis at birth, and the institution of a phenylalanine restricted diet. Dietary treatment, particularly when maintained across neurodevelopment and well into adulthood, has resulted in markedly improved outcomes at a cognitive and psychiatric level for individuals with PKU. However, few individuals can maintain full dietary control lifelong, and even with good control, an elevated risk remains of-in particular-mood, anxiety, and attentional disorders across the lifespan. Increasingly, dietary recommendations focus on maintaining continuous dietary treatment lifelong to optimize psychiatric and cognitive outcomes, although the effect of long-term protein restricted diets on brain function remains unknown. While psychiatric illness is very common in adult PKU populations, very little data exist to guide clinicians on optimal treatment. The advent of new treatments that do not require restrictive dietary management, such as the enzyme therapy Pegvaliase, holds the promise of allowing patients a relatively normal diet alongside optimized mental health and cognitive functioning.
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Affiliation(s)
- Killian Ashe
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Wendy Kelso
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Sarah Farrand
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Julie Panetta
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Tim Fazio
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Medical School, University of Melbourne, Melbourne, VIC, Australia
| | - Gerard De Jong
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Medical School, University of Melbourne, Melbourne, VIC, Australia
| | - Mark Walterfang
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Neuropsychiatry Centre, University of Melbourne and North-Western Mental Health, Melbourne, VIC, Australia.,Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
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23
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Moreira CM, Pereira SV, Raba J, Bertolino FA, Messina GA. Paper-based enzymatic platform coupled to screen printed graphene-modified electrode for the fast neonatal screening of phenylketonuria. Clin Chim Acta 2018; 486:59-65. [DOI: 10.1016/j.cca.2018.07.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/03/2018] [Accepted: 07/09/2018] [Indexed: 12/27/2022]
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24
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Huijbregts SCJ, Bosch AM, Simons QA, Jahja R, Brouwers MCGJ, De Sonneville LMJ, De Vries MC, Hofstede FC, Hollak CEM, Janssen MCH, Langendonk JG, Rubio-Gozalbo ME, Van der Meere JJ, Van der Ploeg AT, Van Spronsen FJ. The impact of metabolic control and tetrahydrobiopterin treatment on health related quality of life of patients with early-treated phenylketonuria: A PKU-COBESO study. Mol Genet Metab 2018; 125:96-103. [PMID: 30007854 DOI: 10.1016/j.ymgme.2018.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 11/20/2022]
Abstract
The aim of this study was to examine Health-Related Quality of Life (HRQoL) of patients with Phenylketonuria (PKU) in three different age groups and to investigate the impact of metabolic control and tetrahydrobiopterin (BH4) treatment on HRQoL of these patients. Participants were 90 early-treated patients aged 7 to 40 years (M = 21.0, SD = 10.1) and 109 controls aged 7 to 40.8 years (M = 19.4, SD = 8.6). HRQoL was assessed with the (generic) TNO-AZL questionnaires. Overall, good HRQoL was reported for children below 12 years of age, although they were judged to be less autonomic than their healthy counterparts. Adolescents aged 12-15 years showed poorer HRQoL in the domain "cognitive functioning" compared to controls. For adults ≥16 years, poorer age-controlled HRQoL was found for the domains cognition, depressive moods, and anger, with a further trend for the domain "pain". With respect to metabolic control, only for adult PKU-patients robust associations were observed, indicating poorer functioning, most notably in the domains cognition, sleep, pain, sexuality and anger, with higher historical and concurrent Phe-levels. With respect to BH4-use, effects on HRQoL were again only observed for adult PKU-patients. After controlling for age and historical Phe-levels, small but significant differences in favor of adult BH4-users compared to non-users were observed for HRQoL-categories happiness, anger, and social functioning. Together, these results show that, particularly for adult PKU-patients, HRQoL-problems are evident and that many of these problems are related to (history of) metabolic control. Beneficial effects of BH4-use appear to be limited to those associated with relief from the practical burdens related to the strict dietary treatment regimen, i.e. general mood and sociability, whereas metabolic control is more strongly related to basic physical and cognitive functioning.
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Affiliation(s)
- Stephan C J Huijbregts
- Department of Clinical Child and Adolescent Studies, Leiden University, Leiden, the Netherlands; Leiden Institute for Brain and Cognition, Leiden University Medical Centre, Leiden, the Netherlands.
| | - Annet M Bosch
- Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Quirine A Simons
- Department of Clinical Child and Adolescent Studies, Leiden University, Leiden, the Netherlands
| | - Rianne Jahja
- Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | | | - Leo M J De Sonneville
- Department of Clinical Child and Adolescent Studies, Leiden University, Leiden, the Netherlands
| | - Maaike C De Vries
- Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Floris C Hofstede
- Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Carla E M Hollak
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Academic Medical Center, Amsterdam, the Netherlands
| | | | | | | | - Jaap J Van der Meere
- Department of Developmental and Clinical Neuropsychology, University of Groningen, Groningen, the Netherlands
| | | | - Francjan J Van Spronsen
- Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, the Netherlands
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25
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Giarratana N, Gallina G, Panzeri V, Frangi A, Canobbio A, Reiner G. A New Phe-Free Protein Substitute Engineered to Allow a Physiological Absorption of Free Amino Acids for Phenylketonuria. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2018. [DOI: 10.1177/2326409818783780] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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26
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Scherer T, Allegri G, Sarkissian CN, Ying M, Grisch-Chan HM, Rassi A, Winn SR, Harding CO, Martinez A, Thöny B. Tetrahydrobiopterin treatment reduces brain L-Phe but only partially improves serotonin in hyperphenylalaninemic ENU1/2 mice. J Inherit Metab Dis 2018; 41:709-718. [PMID: 29520738 PMCID: PMC6041158 DOI: 10.1007/s10545-018-0150-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 01/26/2018] [Accepted: 01/30/2018] [Indexed: 12/16/2022]
Abstract
Hyperphenylalaninemia (HPA) caused by hepatic phenylalanine hydroxylase (PAH) deficiency has severe consequences on brain monoamine neurotransmitter metabolism. We have studied monoamine neurotransmitter status and the effect of tetrahydrobiopterin (BH4) treatment in Pahenu1/enu2 (ENU1/2) mice, a model of partial PAH deficiency. These mice exhibit elevated blood L-phenylalanine (L-Phe) concentrations similar to that of mild hyperphenylalaninemia (HPA), but brain levels of L-Phe are still ~5-fold elevated compared to wild-type. We found that brain L-tyrosine, L-tryptophan, BH4 cofactor and catecholamine concentrations, and brain tyrosine hydroxylase (TH) activity were normal in these mice but that brain serotonin, 5-hydroxyindolacetic acid (5HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) content, and brain TH protein, as well as tryptophan hydroxylase type 2 (TPH2) protein levels and activity were reduced in comparison to wild-type mice. Parenteral L-Phe loading conditions did not lead to significant changes in brain neurometabolite concentrations. Remarkably, enteral BH4 treatment, which normalized brain L-Phe levels in ENU1/2 mice, lead to only partial recovery of brain serotonin and 5HIAA concentrations. Furthermore, indirect evidence indicated that the GTP cyclohydrolase I (GTPCH) feedback regulatory protein (GFRP) complex may be a sensor for brain L-Phe elevation to ameliorate the toxic effects of HPA. We conclude that BH4 treatment of HPA toward systemic L-Phe lowering reverses elevated brain L-Phe content but the recovery of TPH2 protein and activity as well as serotonin levels is suboptimal, indicating that patients with mild HPA and mood problems (depression or anxiety) treated with the current diet may benefit from supplementation with BH4 and 5-OH-tryptophan.
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Affiliation(s)
- Tanja Scherer
- Department of Pediatrics, Divisions of Metabolism and of Clinical Chemistry and Biochemistry, University of Zürich, Zürich, Switzerland
| | - Gabriella Allegri
- Department of Pediatrics, Divisions of Metabolism and of Clinical Chemistry and Biochemistry, University of Zürich, Zürich, Switzerland
| | | | - Ming Ying
- Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders, University of Bergen, Bergen, Norway
| | - Hiu Man Grisch-Chan
- Department of Pediatrics, Divisions of Metabolism and of Clinical Chemistry and Biochemistry, University of Zürich, Zürich, Switzerland
| | - Anahita Rassi
- Department of Pediatrics, Divisions of Metabolism and of Clinical Chemistry and Biochemistry, University of Zürich, Zürich, Switzerland
| | - Shelley R Winn
- Department of Molecular and Medical Genetics, School of Medicine, Oregon Science & Health University, Portland, OR, USA
| | - Cary O Harding
- Department of Molecular and Medical Genetics, School of Medicine, Oregon Science & Health University, Portland, OR, USA
| | - Aurora Martinez
- Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders, University of Bergen, Bergen, Norway.
| | - Beat Thöny
- Department of Pediatrics, Divisions of Metabolism and of Clinical Chemistry and Biochemistry, University of Zürich, Zürich, Switzerland.
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27
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Xie F, Peng F. Radiopharmaceuticals for Assessment of Altered Metabolism and Biometal Fluxes in Brain Aging and Alzheimer's Disease with Positron Emission Tomography. J Alzheimers Dis 2018; 59:527-536. [PMID: 28671127 DOI: 10.3233/jad-170280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Aging is a risk factor for Alzheimer's disease (AD). There are changes of brain metabolism and biometal fluxes due to brain aging, which may play a role in pathogenesis of AD. Positron emission tomography (PET) is a versatile tool for tracking alteration of metabolism and biometal fluxes due to brain aging and AD. Age-dependent changes in cerebral glucose metabolism can be tracked with PET using 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG), a radiolabeled glucose analogue, as a radiotracer. Based on different patterns of altered cerebral glucose metabolism, 18F-FDG PET was clinically used for differential diagnosis of AD and Frontotemporal dementia (FTD). There are continued efforts to develop additional radiopharmaceuticals or radiotracers for assessment of age-dependent changes of various metabolic pathways and biometal fluxes due to brain aging and AD with PET. Elucidation of age-dependent changes of brain metabolism and altered biometal fluxes is not only significant for a better mechanistic understanding of brain aging and the pathophysiology of AD, but also significant for identification of new targets for the prevention, early diagnosis, and treatment of AD.
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Affiliation(s)
- Fang Xie
- Department of Radiology, and Advanced ImagingResearch Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Fangyu Peng
- Department of Radiology, and Advanced ImagingResearch Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
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28
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Didycz B, Bik-Multanowski M. Blood phenylalanine instability strongly correlates with anxiety in phenylketonuria. Mol Genet Metab Rep 2017; 14:80-82. [PMID: 29326880 PMCID: PMC5758931 DOI: 10.1016/j.ymgmr.2017.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/07/2017] [Accepted: 12/07/2017] [Indexed: 01/11/2023] Open
Abstract
We assessed the relationship between anxiety and long-term metabolic control in adolescents with phenylketonuria (PKU). We used a standardized psychological test to measure anxiety level and analyzed lifelong blood phenylalanine stability in a selected group of 25 PKU teenagers with treatment adherence problems. We demonstrated significant correlations of anxiety with variability of blood phenylalanine concentrations and with severity of hyperphenylalaninemia. Avoiding blood phenylalanine fluctuations in childhood can probably reduce anxiety in PKU adolescents.
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Affiliation(s)
- Bozena Didycz
- Department of Medical Genetics, Jagiellonian University Medical College, Krakow, Poland
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29
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van Wegberg AMJ, MacDonald A, Ahring K, Bélanger-Quintana A, Blau N, Bosch AM, Burlina A, Campistol J, Feillet F, Giżewska M, Huijbregts SC, Kearney S, Leuzzi V, Maillot F, Muntau AC, van Rijn M, Trefz F, Walter JH, van Spronsen FJ. The complete European guidelines on phenylketonuria: diagnosis and treatment. Orphanet J Rare Dis 2017; 12:162. [PMID: 29025426 PMCID: PMC5639803 DOI: 10.1186/s13023-017-0685-2] [Citation(s) in RCA: 421] [Impact Index Per Article: 60.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 07/11/2017] [Indexed: 12/22/2022] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive inborn error of phenylalanine metabolism caused by deficiency in the enzyme phenylalanine hydroxylase that converts phenylalanine into tyrosine. If left untreated, PKU results in increased phenylalanine concentrations in blood and brain, which cause severe intellectual disability, epilepsy and behavioural problems. PKU management differs widely across Europe and therefore these guidelines have been developed aiming to optimize and standardize PKU care. Professionals from 10 different European countries developed the guidelines according to the AGREE (Appraisal of Guidelines for Research and Evaluation) method. Literature search, critical appraisal and evidence grading were conducted according to the SIGN (Scottish Intercollegiate Guidelines Network) method. The Delphi-method was used when there was no or little evidence available. External consultants reviewed the guidelines. Using these methods 70 statements were formulated based on the highest quality evidence available. The level of evidence of most recommendations is C or D. Although study designs and patient numbers are sub-optimal, many statements are convincing, important and relevant. In addition, knowledge gaps are identified which require further research in order to direct better care for the future.
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Affiliation(s)
- A. M. J. van Wegberg
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - A. MacDonald
- Dietetic Department, Birmingham Children’s Hospital, Birmingham, UK
| | - K. Ahring
- Department of PKU, Kennedy Centre, Glostrup, Denmark
| | - A. Bélanger-Quintana
- Metabolic Diseases Unit, Department of Paediatrics, Hospital Ramon y Cajal Madrid, Madrid, Spain
| | - N. Blau
- University Children’s Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany
- University Children’s Hospital Zürich, Zürich, Switzerland
| | - A. M. Bosch
- Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, The Netherlands
| | - A. Burlina
- Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy
| | - J. Campistol
- Neuropaediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain
| | - F. Feillet
- Department of Paediatrics, Hôpital d’Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France
| | - M. Giżewska
- Department of Paediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology of the Developmental Age, Pomeranian Medical University, Szczecin, Poland
| | - S. C. Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, The Netherlands
| | - S. Kearney
- Clinical Psychology Department, Birmingham Children’s Hospital, Birmingham, UK
| | - V. Leuzzi
- Department of Paediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Via dei Sabelli 108, 00185 Rome, Italy
| | - F. Maillot
- CHRU de Tours, Université François Rabelais, INSERM U1069, Tours, France
| | - A. C. Muntau
- University Children’s Hospital, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - M. van Rijn
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - F. Trefz
- Department of Paediatrics, University of Heidelberg, Heidelberg, Germany
| | - J. H. Walter
- Medicine, Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - F. J. van Spronsen
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
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van Spronsen FJ, van Wegberg AM, Ahring K, Bélanger-Quintana A, Blau N, Bosch AM, Burlina A, Campistol J, Feillet F, Giżewska M, Huijbregts SC, Kearney S, Leuzzi V, Maillot F, Muntau AC, Trefz FK, van Rijn M, Walter JH, MacDonald A. Key European guidelines for the diagnosis and management of patients with phenylketonuria. Lancet Diabetes Endocrinol 2017; 5:743-756. [PMID: 28082082 DOI: 10.1016/s2213-8587(16)30320-5] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/11/2016] [Accepted: 09/28/2016] [Indexed: 12/14/2022]
Abstract
We developed European guidelines to optimise phenylketonuria (PKU) care. To develop the guidelines, we did a literature search, critical appraisal, and evidence grading according to the Scottish Intercollegiate Guidelines Network method. We used the Delphi method when little or no evidence was available. From the 70 recommendations formulated, in this Review we describe ten that we deem as having the highest priority. Diet is the cornerstone of treatment, although some patients can benefit from tetrahydrobiopterin (BH4). Untreated blood phenylalanine concentrations determine management of people with PKU. No intervention is required if the blood phenylalanine concentration is less than 360 μmol/L. Treatment is recommended up to the age of 12 years if the phenylalanine blood concentration is between 360 μmol/L and 600 μmol/L, and lifelong treatment is recommended if the concentration is more than 600 μmol/L. For women trying to conceive and during pregnancy (maternal PKU), untreated phenylalanine blood concentrations of more than 360 μmol/L need to be reduced. Treatment target concentrations are as follows: 120-360 μmol/L for individuals aged 0-12 years and for maternal PKU, and 120-600 μmol/L for non-pregnant individuals older than 12 years. Minimum requirements for the management and follow-up of patients with PKU are scheduled according to age, adherence to treatment, and clinical status. Nutritional, clinical, and biochemical follow-up is necessary for all patients, regardless of therapy.
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Affiliation(s)
- Francjan J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
| | - Annemiek Mj van Wegberg
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Kirsten Ahring
- Department of PKU, Kennedy Centre, Copenhagen University Hospital, Glostrup, Denmark
| | | | - Nenad Blau
- University Children's Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany; University Children's Hospital Zurich, Zurich, Switzerland
| | - Annet M Bosch
- Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, Netherlands
| | - Alberto Burlina
- Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy
| | - Jaime Campistol
- Neuropaediatrics Department, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain
| | - Francois Feillet
- Department of Pediatrics, Hôpital d'Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France
| | - Maria Giżewska
- Department of Pediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology of the Developmental Age, Pomeranian Medical University, Szczecin, Poland
| | - Stephan C Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, Netherlands
| | - Shauna Kearney
- Clinical Psychology Department, Birmingham Children's Hospital, Birmingham, UK
| | - Vincenzo Leuzzi
- Department of Pediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy
| | - Francois Maillot
- Internal Medicine Service, CHRU de Tours, François Rabelais University, Tours, France
| | - Ania C Muntau
- University Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fritz K Trefz
- University Children's Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany
| | - Margreet van Rijn
- Department of Dietetics, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - John H Walter
- Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - Anita MacDonald
- Dietetic Department, Birmingham Children's Hospital, Birmingham, UK
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Xu Z, Chen T, Luo J, Ding S, Gao S, Zhang J. Cartilaginous Metabolomic Study Reveals Potential Mechanisms of Osteophyte Formation in Osteoarthritis. J Proteome Res 2017; 16:1425-1435. [PMID: 28166636 DOI: 10.1021/acs.jproteome.6b00676] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Osteophyte is one of the inevitable consequences of progressive osteoarthritis with the main characteristics of cartilage degeneration and endochondral ossification. The pathogenesis of osteophyte formation is not fully understood to date. In this work, metabolomic approaches were employed to explore potential mechanisms of osteophyte formation by detecting metabolic variations between extracts of osteophyte cartilage tissues (n = 32) and uninvolved control cartilage tissues (n = 34), based on the platform of ultraperformance liquid chromatography tandem quadrupole time-of-flight mass spectrometry, as well as the use of multivariate statistic analysis and univariate statistic analysis. The osteophyte group was significantly separated from the control group by the orthogonal partial least-squares discriminant analysis models, indicating that metabolic state of osteophyte cartilage had been changed. In total, 28 metabolic variations further validated by mass spectrum (MS) match, tandom mass spectrum (MS/MS) match, and standards match mainly included amino acids, sulfonic acids, glycerophospholipids, and fatty acyls. These metabolites were related to some specific physiological or pathological processes (collagen dissolution, boundary layers destroyed, self-restoration triggered, etc.) which might be associated with the procedure of osteophyte formation. Pathway analysis showed phenylalanine metabolism (PI = 0.168, p = 0.004) was highly correlative to this degenerative process. Our findings provided a direction for targeted metabolomic study and an insight into further reveal the molecular mechanisms of ostophyte formation.
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Affiliation(s)
- Zhongwei Xu
- Department of Orthopaedics, The First Affiliated Hospital of Chongqing Medical University , Chongqing 400016, China
| | - Tingmei Chen
- Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University , Chongqing 400016, China
| | - Jiao Luo
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University , Chengdu 610041, China
| | - Shijia Ding
- Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University , Chongqing 400016, China
| | - Sichuan Gao
- Department of Orthopaedics, The First Affiliated Hospital of Chongqing Medical University , Chongqing 400016, China
| | - Jian Zhang
- Department of Orthopaedics, The First Affiliated Hospital of Chongqing Medical University , Chongqing 400016, China
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Caprile C, Campistol J, Puigcerver L, Gutiérrez-Mata AP, Alonso-Colmenero I, Colomé R, Navarra J. Subtle visuomotor deficits and reduced benefit from practice in early treated phenylketonuria. J Clin Exp Neuropsychol 2017; 39:931-940. [PMID: 28165881 DOI: 10.1080/13803395.2017.1281381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Phenylketonuria (PKU) is a rare metabolic disease that causes slight-to-severe neurological symptoms. Slow performance has been observed in PKU but the influence of high-order (i.e., not purely motor) deficits and of temporary variations of the phenylalanine (Phe) level on this slowness has not been fully corroborated as yet. Response speed and the effect of motor practice during the performance of a visuomotor coordination task were measured, in a group of patients with early-treated phenylketonuria (ET PKU). METHOD We compared the performance of a group of early-treated PKU patients with ages ranging from 11 to 25 years and a control group of healthy volunteers on a computerized visuomotor task. Participants performed rapid movements towards one of five response buttons, as indicated by a visual stimulus that could appear in five different positions on a computer screen. The results of our visuomotor task were correlated with neurobiological data (Phe levels) and with neuropsychological measures of motor (finger tapping) and executive functions (Stroop task). RESULTS The ET PKU group showed slower responses than the control group. Furthermore, an absence of a practice effect (i.e., faster response times at the end of the study) was found in the PKU group but not in the control group. Our results also revealed that this absence of practice effect correlated with higher Phe levels on the testing day with respect to the average Phe level of the previous 12 months and, although weakly, with performance on the Stroop task. CONCLUSIONS This pattern of results indicates slower visuomotor performance and a less beneficial effect of practice in ET PKU. The correlations found among our visuomotor measures, the same-day Phe level, and the Stroop test may reflect the negative effects of dopamine reduction in brain areas involved in motor control, selective attention, and learning.
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Affiliation(s)
- Claudia Caprile
- a Experimental Psychology & Brain Disorders Laboratory , Fundació Sant Joan de Déu, Hospital Sant Joan de Déu , Esplugues de Llobregat, Barcelona , Spain
| | - Jaume Campistol
- b Servei de Neurologia Pediàtrica , Hospital Sant Joan de Déu , Esplugues de Llobregat, Barcelona , Spain
| | - Laura Puigcerver
- a Experimental Psychology & Brain Disorders Laboratory , Fundació Sant Joan de Déu, Hospital Sant Joan de Déu , Esplugues de Llobregat, Barcelona , Spain.,c Department of Cognition, Development and Educational Psychology , University of Barcelona , Barcelona , Spain
| | | | - Itziar Alonso-Colmenero
- b Servei de Neurologia Pediàtrica , Hospital Sant Joan de Déu , Esplugues de Llobregat, Barcelona , Spain
| | - Roser Colomé
- e UTAE Learning Disorders Unit , Hospital Sant Joan de Déu , Barcelona , Spain
| | - Jordi Navarra
- a Experimental Psychology & Brain Disorders Laboratory , Fundació Sant Joan de Déu, Hospital Sant Joan de Déu , Esplugues de Llobregat, Barcelona , Spain.,c Department of Cognition, Development and Educational Psychology , University of Barcelona , Barcelona , Spain
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Bilder DA, Noel JK, Baker ER, Irish W, Chen Y, Merilainen MJ, Prasad S, Winslow BJ. Systematic Review and Meta-Analysis of Neuropsychiatric Symptoms and Executive Functioning in Adults With Phenylketonuria. Dev Neuropsychol 2016; 41:245-260. [PMID: 27805419 PMCID: PMC5152552 DOI: 10.1080/87565641.2016.1243109] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This systematic review and meta-analysis (MA) investigates the impact of elevated blood phenylalanine (Phe) on neuropsychiatric symptoms in adults with phenylketonuria (PKU). The meta-analysis of PKU is challenging because high-quality evidence is lacking due to the limited number of affected individuals and few placebo-controlled, double-blind studies of adults with high and low blood Phe. Neuropsychiatric symptoms associated with PKU exceed general population estimates for inattention, hyperactivity, depression, and anxiety. High Phe is associated with an increased prevalence of neuropsychiatric symptoms and executive functioning deficits whereas low Phe is associated with improved neurological performance. Findings support lifelong maintenance of low blood Phe.
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Affiliation(s)
- Deborah A Bilder
- a Department of Psychiatry , University of Utah , Salt Lake City , Utah
| | - J Kay Noel
- b CTI Clinical Trial and Consulting Services Inc ., Cincinnati , Ohio
| | - Erin R Baker
- b CTI Clinical Trial and Consulting Services Inc ., Cincinnati , Ohio
| | - William Irish
- b CTI Clinical Trial and Consulting Services Inc ., Cincinnati , Ohio
| | - Yinpu Chen
- c BioMarin Pharmaceutical Inc ., Novato , California
| | | | - Suyash Prasad
- d Audentes Therapeutics , San Francisco , California
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Abstract
Cerebral neurotransmitter (NT) deficiency has been suggested as a contributing factor in the pathophysiology of brain dysfunction in phenylketonuria (PKU), even in early-treated phenylketonuric patients. The study aimed to review dopamine and serotonin status in PKU, and the effect of the impaired neurotransmission. Several mechanisms are involved in the pathophysiology of PKU, primarily characterized by impaired dopamine and serotonin synthesis. These deficits are related to executive dysfunctions and social-emotional problems, respectively, in early treated patients. Blood phenylalanine is the main biomarker for treatment compliance follow-up, but further investigations and validation of peripheral biomarkers may be performed to monitor NT status. The development of new therapies is needed not only for decreasing blood and brain phenylalanine levels but also to improve NT syntheses.
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van Vliet D, Bruinenberg VM, Mazzola PN, van Faassen MH, de Blaauw P, Pascucci T, Puglisi-Allegra S, Kema IP, Heiner-Fokkema MR, van der Zee EA, van Spronsen FJ. Therapeutic brain modulation with targeted large neutral amino acid supplements in the Pah-enu2 phenylketonuria mouse model. Am J Clin Nutr 2016; 104:1292-1300. [PMID: 27655443 DOI: 10.3945/ajcn.116.135996] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/24/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Phenylketonuria treatment consists mainly of a Phe-restricted diet, which leads to suboptimal neurocognitive and psychosocial outcomes. Supplementation of large neutral amino acids (LNAAs) has been suggested as an alternative dietary treatment strategy to optimize neurocognitive outcome in phenylketonuria and has been shown to influence 3 brain pathobiochemical mechanisms in phenylketonuria, but its optimal composition has not been established. OBJECTIVE In order to provide additional pathobiochemical insight and develop optimal LNAA treatment, several targeted LNAA supplements were investigated with respect to all 3 biochemical disturbances underlying brain dysfunction in phenylketonuria. DESIGN Pah-enu2 (PKU) mice received 1 of 5 different LNAA-supplemented diets beginning at postnatal day 45. Control groups included phenylketonuria mice receiving an isonitrogenic and isocaloric high-protein diet or the AIN-93M diet, and wild-type mice receiving the AIN-93M diet. After 6 wk, brain and plasma amino acid profiles and brain monoaminergic neurotransmitter concentrations were measured. RESULTS Brain Phe concentrations were most effectively reduced by supplementation of LNAAs, such as Leu and Ile, with a strong affinity for the LNAA transporter type 1. Brain non-Phe LNAAs could be restored on supplementation, but unbalanced LNAA supplementation further reduced brain concentrations of those LNAAs that were not (sufficiently) included in the LNAA supplement. To optimally ameliorate brain monoaminergic neurotransmitter concentrations, LNAA supplementation should include Tyr and Trp together with LNAAs that effectively reduce brain Phe concentrations. The requirement for Tyr supplementation is higher than it is for Trp, and the relative effect of brain Phe reduction is higher for serotonin than it is for dopamine and norepinephrine. CONCLUSION The study shows that all 3 biochemical disturbances underlying brain dysfunction in phenylketonuria can be targeted by specific LNAA supplements. The study thus provides essential information for the development of optimal LNAA supplementation as an alternative dietary treatment strategy to optimize neurocognitive outcome in patients with phenylketonuria.
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Affiliation(s)
- Danique van Vliet
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, Netherlands
| | - Vibeke M Bruinenberg
- Department of Molecular Neurobiology, University of Groningen, Groningen Institute for Evolutionary Life Sciences, Groningen, Netherlands
| | - Priscila N Mazzola
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, Netherlands.,Department of Molecular Neurobiology, University of Groningen, Groningen Institute for Evolutionary Life Sciences, Groningen, Netherlands
| | - Martijn Hjr van Faassen
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Pim de Blaauw
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Tiziana Pascucci
- Department of Psychology and Centro "Daniel Bovet," "La Sapienza" University, Fondazione Santa Lucia, Rome, Italy; and.,Fondazione Santa Lucia, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Stefano Puglisi-Allegra
- Department of Psychology and Centro "Daniel Bovet," "La Sapienza" University, Fondazione Santa Lucia, Rome, Italy; and.,Fondazione Santa Lucia, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Ido P Kema
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - M Rebecca Heiner-Fokkema
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Eddy A van der Zee
- Department of Molecular Neurobiology, University of Groningen, Groningen Institute for Evolutionary Life Sciences, Groningen, Netherlands
| | - Francjan J van Spronsen
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, Netherlands;
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Li S, Sun QL, Zhou Y, Zhang Y, Hu XJ, Hong WS, Ji GP. [Factors influencing the quality of life of 104 children with phenylketonuria in Anhui Province, China]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2016; 18:702-706. [PMID: 27530785 PMCID: PMC7399507 DOI: 10.7499/j.issn.1008-8830.2016.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/25/2016] [Indexed: 06/06/2023]
Abstract
OBJECTIVE To investigate the factors influencing the quality of life (QOL) of children with phenylketonuria (PKU) in Anhui Province, China. METHODS A total of 104 PKU children who were diagnosed and treated in three major maternal and child health hospitals in Anhui Province were enrolled as study subjects. The PedsQL™ 4.0 Generic Core Scales were used to evaluate the quality of life of these children. The multivariate logistic regression analysis was used to evaluate the factors influencing the QOL. RESULTS The 104 PKU children had significantly lower overall QOL score and scores on the subscales of physiological functioning, emotional functioning, and social functioning than the general school-age children (P<0.01). They also had a significantly lower score on the physiological domain consisting of emotional functioning, social functioning, and role functioning than the general school-age children (P<0.01). The multivariate logistic regression analysis showed that an older age (≥4 years) of PKU children was the risk factor for poor QOL (OR=8.569, P<0.01), and guardians' engagement at enterprises or institutions was the protective factor for QOL (OR=0.206, P<0.05). CONCLUSIONS PKU children have a low level of QOL, and age and guardians' occupation are factors influencing the QOL.
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Affiliation(s)
- Song Li
- Hospital Administration Office, Chaohu Hospital, Anhui Medical University, Hefei 238000, China.
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Winn SR, Scherer T, Thöny B, Harding CO. High dose sapropterin dihydrochloride therapy improves monoamine neurotransmitter turnover in murine phenylketonuria (PKU). Mol Genet Metab 2016; 117:5-11. [PMID: 26653793 PMCID: PMC4706464 DOI: 10.1016/j.ymgme.2015.11.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 11/25/2015] [Indexed: 01/08/2023]
Abstract
Central nervous system (CNS) deficiencies of the monoamine neurotransmitters, dopamine and serotonin, have been implicated in the pathophysiology of neuropsychiatric dysfunction in phenylketonuria (PKU). Increased brain phenylalanine concentration likely competitively inhibits the activities of tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), the rate limiting steps in dopamine and serotonin synthesis respectively. Tetrahydrobiopterin (BH4) is a required cofactor for TH and TPH activity. Our hypothesis was that treatment of hyperphenylalaninemic Pah(enu2/enu2) mice, a model of human PKU, with sapropterin dihydrochloride, a synthetic form of BH4, would stimulate TH and TPH activities leading to improved dopamine and serotonin synthesis despite persistently elevated brain phenylalanine. Sapropterin (20, 40, or 100mg/kg body weight in 1% ascorbic acid) was administered daily for 4 days by oral gavage to Pah(enu2/enu2) mice followed by measurement of brain biopterin, phenylalanine, tyrosine, tryptophan and monoamine neurotransmitter content. A significant increase in brain biopterin content was detected only in mice that had received the highest sapropterin dose, 100mg/kg. Blood and brain phenylalanine concentrations were unchanged by sapropterin therapy. Sapropterin therapy also did not alter the absolute amounts of dopamine and serotonin in brain but was associated with increased homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), dopamine and serotonin metabolites respectively, in both wild type and Pah(enu2/enu2) mice. Oral sapropterin therapy likely does not directly affect central nervous system monoamine synthesis in either wild type or hyperphenylalaninemic mice but may stimulate synaptic neurotransmitter release and subsequent metabolism.
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Affiliation(s)
- Shelley R Winn
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Mailstop L-103, 3181 Sam Jackson Park Rd., Portland, OR 97239, USA
| | - Tanja Scherer
- Department of Pediatrics, University of Zurich, Steinweissstrasse 75, Zurich CH-8032, Switzerland
| | - Beat Thöny
- Department of Pediatrics, University of Zurich, Steinweissstrasse 75, Zurich CH-8032, Switzerland
| | - Cary O Harding
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Mailstop L-103, 3181 Sam Jackson Park Rd., Portland, OR 97239, USA.
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In Vivo NMR Studies of the Brain with Hereditary or Acquired Metabolic Disorders. Neurochem Res 2015; 40:2647-85. [PMID: 26610379 DOI: 10.1007/s11064-015-1772-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 11/10/2015] [Accepted: 11/12/2015] [Indexed: 01/09/2023]
Abstract
Metabolic disorders, whether hereditary or acquired, affect the brain, and abnormalities of the brain are related to cellular integrity; particularly in regard to neurons and astrocytes as well as interactions between them. Metabolic disturbances lead to alterations in cellular function as well as microscopic and macroscopic structural changes in the brain with diabetes, the most typical example of metabolic disorders, and a number of hereditary metabolic disorders. Alternatively, cellular dysfunction and degeneration of the brain lead to metabolic disturbances in hereditary neurological disorders with neurodegeneration. Nuclear magnetic resonance (NMR) techniques allow us to assess a range of pathophysiological changes of the brain in vivo. For example, magnetic resonance spectroscopy detects alterations in brain metabolism and energetics. Physiological magnetic resonance imaging (MRI) detects accompanying changes in cerebral blood flow related to neurovascular coupling. Diffusion and T1/T2-weighted MRI detect microscopic and macroscopic changes of the brain structure. This review summarizes current NMR findings of functional, physiological and biochemical alterations within a number of hereditary and acquired metabolic disorders in both animal models and humans. The global view of the impact of these metabolic disorders on the brain may be useful in identifying the unique and/or general patterns of abnormalities in the living brain related to the pathophysiology of the diseases, and identifying future fields of inquiry.
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Schuck PF, Malgarin F, Cararo JH, Cardoso F, Streck EL, Ferreira GC. Phenylketonuria Pathophysiology: on the Role of Metabolic Alterations. Aging Dis 2015; 6:390-9. [PMID: 26425393 DOI: 10.14336/ad.2015.0827] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 08/27/2015] [Indexed: 11/01/2022] Open
Abstract
Phenylketonuria (PKU) is an inborn error of phenylalanine (Phe) metabolism caused by the deficiency of phenylalanine hydroxylase. This deficiency leads to the accumulation of Phe and its metabolites in tissues and body fluids of PKU patients. The main signs and symptoms are found in the brain but the pathophysiology of this disease is not well understood. In this context, metabolic alterations such as oxidative stress, mitochondrial dysfunction, and impaired protein and neurotransmitters synthesis have been described both in animal models and patients. This review aims to discuss the main metabolic disturbances reported in PKU and relate them with the pathophysiology of this disease. The elucidation of the pathophysiology of brain damage found in PKU patients will help to develop better therapeutic strategies to improve quality of life of patients affected by this condition.
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Affiliation(s)
- Patrícia Fernanda Schuck
- 1 Laboratório de Erros Inatos do Metabolismo, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Fernanda Malgarin
- 1 Laboratório de Erros Inatos do Metabolismo, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - José Henrique Cararo
- 1 Laboratório de Erros Inatos do Metabolismo, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Fabiola Cardoso
- 2 Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Emilio Luiz Streck
- 3 Laboratório de Bioenergética, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Gustavo Costa Ferreira
- 2 Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Burton B, Grant M, Feigenbaum A, Singh R, Hendren R, Siriwardena K, Phillips J, Sanchez-Valle A, Waisbren S, Gillis J, Prasad S, Merilainen M, Lang W, Zhang C, Yu S, Stahl S. A randomized, placebo-controlled, double-blind study of sapropterin to treat ADHD symptoms and executive function impairment in children and adults with sapropterin-responsive phenylketonuria. Mol Genet Metab 2015; 114:415-24. [PMID: 25533024 DOI: 10.1016/j.ymgme.2014.11.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 11/17/2014] [Accepted: 11/18/2014] [Indexed: 11/23/2022]
Abstract
Symptoms of attention deficit-hyperactivity disorder (ADHD), particularly inattention, and impairments in executive functioning have been reported in early and continuously treated children, adolescents, and adults with phenylketonuria (PKU). In addition, higher blood phenylalanine (Phe) levels have been correlated with the presence of ADHD symptoms and executive functioning impairment. The placebo-controlled PKU ASCEND study evaluated the effects of sapropterin therapy on PKU-associated symptoms of ADHD and executive and global functioning in individuals who had a therapeutic blood Phe response to sapropterin therapy. The presence of ADHD inattentive symptoms and executive functioning deficits was confirmed in this large cohort of 206 children and adults with PKU, of whom 118 responded to sapropterin therapy. In the 38 individuals with sapropterin-responsive PKU and ADHD symptoms at baseline, sapropterin therapy resulted in a significant improvement in ADHD inattentive symptoms in the first 4 weeks of treatment, and improvements were maintained throughout the 26 weeks of treatment. Sapropterin was well-tolerated with a favorable safety profile. The improvements in ADHD inattentive symptoms and aspects of executive functioning in response to sapropterin therapy noted in a large cohort of individuals with PKU indicate that these symptoms are potentially reversible when blood Phe levels are reduced.
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Affiliation(s)
- B Burton
- The Ann and Robert H. Lurie Children's Hospital and the Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - M Grant
- Drexel University College of Medicine, Philadelphia, PA, USA
| | - A Feigenbaum
- The Hospital for Sick Children and University of Toronto, ON, Canada
| | - R Singh
- Emory University School of Medicine, Decatur, GA, USA
| | - R Hendren
- University of California, San Francisco, San Francisco, CA, USA
| | - K Siriwardena
- Drexel University College of Medicine, Philadelphia, PA, USA
| | - J Phillips
- Vanderbilt University School of Medicine, Nashville, TN, USA
| | - A Sanchez-Valle
- University of South Florida and Tampa General Hospital, Tampa, FL, USA
| | - S Waisbren
- Boston Children's Hospital, Boston, MA, USA
| | - J Gillis
- IWK Health Centre Maritime Medical Genetics Services, Halifax, NS, Canada
| | - S Prasad
- BioMarin Pharmaceutical Inc., Novato, CA, USA
| | | | - W Lang
- BioMarin Pharmaceutical Inc., Novato, CA, USA
| | - C Zhang
- BioMarin Pharmaceutical Inc., Novato, CA, USA
| | - S Yu
- BioMarin Pharmaceutical Inc., Novato, CA, USA
| | - S Stahl
- University of California, San Diego School of Medicine, San Diego, CA, USA
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41
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de Groot MJ, Sijens PE, Reijngoud DJ, Paans AM, van Spronsen FJ. Phenylketonuria: brain phenylalanine concentrations relate inversely to cerebral protein synthesis. J Cereb Blood Flow Metab 2015; 35:200-5. [PMID: 25352046 PMCID: PMC4426736 DOI: 10.1038/jcbfm.2014.183] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/19/2014] [Accepted: 09/04/2014] [Indexed: 11/09/2022]
Abstract
In phenylketonuria, elevated plasma phenylalanine concentrations may disturb blood-to-brain large neutral amino acid (LNAA) transport and cerebral protein synthesis (CPS). We investigated the associations between these processes, using data obtained by positron emission tomography with l-[1-(11)C]-tyrosine ((11)C-Tyr) as a tracer. Blood-to-brain transport of non-Phe LNAAs was modeled by the rate constant for (11)C-Tyr transport from arterial plasma to brain tissue (K1), while CPS was modeled by the rate constant for (11)C-Tyr incorporation into cerebral protein (k3). Brain phenylalanine concentrations were measured by magnetic resonance spectroscopy in three volumes of interest (VOIs): supraventricular brain tissue (VOI 1), ventricular brain tissue (VOI 2), and fluid-containing ventricular voxels (VOI 3). The associations between k3 and each predictor variable were analyzed by multiple linear regression. The rate constant k3 was inversely associated with brain phenylalanine concentrations in VOIs 2 and 3 (adjusted R(2)=0.826, F=19.936, P=0.021). Since brain phenylalanine concentrations in these VOIs highly correlated with each other, the specific associations of each predictor with k3 could not be determined. The associations between k3 and plasma phenylalanine concentration, K1, and brain phenylalanine concentrations in VOI 1 were nonsignificant. In conclusion, our study shows an inverse association between k3 and increased brain phenylalanine concentrations.
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Affiliation(s)
- Martijn J de Groot
- 1] Department of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands [2] Department of Digestive and Metabolic Diseases, Center for Liver, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Paul E Sijens
- Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Dirk-Jan Reijngoud
- 1] Department of Digestive and Metabolic Diseases, Center for Liver, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands [2] Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Anne M Paans
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Francjan J van Spronsen
- 1] Department of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands [2] Department of Digestive and Metabolic Diseases, Center for Liver, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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42
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Hood A, Antenor-Dorsey JAV, Rutlin J, Hershey T, Shimony JS, McKinstry RC, Grange DK, Christ SE, Steiner R, White DA. Prolonged exposure to high and variable phenylalanine levels over the lifetime predicts brain white matter integrity in children with phenylketonuria. Mol Genet Metab 2015; 114:19-24. [PMID: 25481106 PMCID: PMC4277899 DOI: 10.1016/j.ymgme.2014.11.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/04/2014] [Accepted: 11/06/2014] [Indexed: 10/24/2022]
Abstract
In this study, we retrospectively examined the microstructural white matter integrity of children with early- and continuously-treated PKU (N=36) in relation to multiple indices of phenylalanine (Phe) control over the lifetime. White matter integrity was assessed using mean diffusivity (MD) from diffusion tensor imaging (DTI). Eight lifetime indices of Phe control were computed to reflect average Phe (mean, index of dietary control), variability in Phe (standard deviation, standard error of estimate, % spikes), change in Phe with age (slope), and prolonged exposure to Phe (mean exposure, standard deviation exposure). Of these indices, mean Phe, mean exposure, and standard deviation exposure were the most powerful predictors of widespread microstructural white matter integrity compromise. Findings from the two previously unexamined exposure indices reflected the accumulative effects of elevations and variability in Phe. Given that prolonged exposure to elevated and variable Phe was particularly detrimental to white matter integrity, Phe should be carefully monitored and controlled throughout childhood, without liberalization of Phe control as children with PKU age.
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Affiliation(s)
- Anna Hood
- Department of Psychology, Washington University, Campus Box 1125, St. Louis, MO 63130, USA
| | - Jo Ann V Antenor-Dorsey
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, St. Louis, MO 63110, USA
| | - Jerrel Rutlin
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, St. Louis, MO 63110, USA
| | - Tamara Hershey
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, St. Louis, MO 63110, USA; Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8131, St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, Campus Box 8111, St. Louis, MO 63110, USA
| | - Joshua S Shimony
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8131, St. Louis, MO 63110, USA
| | - Robert C McKinstry
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8131, St. Louis, MO 63110, USA; Department of Pediatrics, Washington University School of Medicine, Campus Box 8116, St. Louis, MO 63110, USA
| | - Dorothy K Grange
- Department of Pediatrics, Washington University School of Medicine, Campus Box 8116, St. Louis, MO 63110, USA
| | - Shawn E Christ
- Department of Psychological Sciences, University of Missouri, 210 McAlester Hall, Columbia, MO 65211, USA
| | - Robert Steiner
- Department of Pediatrics, Institute on Development and Disability, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR, 97239 USA; Department of Molecular & Medical Genetics, Institute on Development and Disability, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, USA
| | - Desiree A White
- Department of Psychology, Washington University, Campus Box 1125, St. Louis, MO 63130, USA.
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Sanayama Y, Matsumoto A, Shimojo N, Kohno Y, Nakaya H. Phenylalanine sensitive K562-D cells for the analysis of the biochemical impact of excess amino acid. Sci Rep 2014; 4:6941. [PMID: 25373594 PMCID: PMC4221789 DOI: 10.1038/srep06941] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 10/20/2014] [Indexed: 12/31/2022] Open
Abstract
Although it is recognized that the abnormal accumulation of amino acid is a cause of the symptoms in metabolic disease such as phenylketonuria (PKU), the relationship between disease severity and serum amino acid levels is not well understood due to the lack of experimental model. Here, we present a novel in vitro cellular model using K562-D cells that proliferate slowly in the presence of excessive amount of phenylalanine within the clinically observed range, but not phenylpyruvate. The increased expression of the L-type amino acid transporter (LAT2) and its adapter protein 4F2 heavy chain appeared to be responsible for the higher sensitivity to phenylalanine in K562-D cells. Supplementation with valine over phenylalanine effectively restored cell proliferation, although other amino acids did not improve K562-D cell proliferation over phenylalanine. Biochemical analysis revealed mammalian target of rapamycin complex (mTORC) as a terminal target of phenylalanine in K562-D cell proliferation, and supplementation of valine restored mTORC1 activity. Our results show that K562-D cell can be a potent tool for the investigation of PKU at the molecular level and to explore new therapeutic approaches to the disease.
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Affiliation(s)
- Yoshitami Sanayama
- 1] Department of Pharmacology, Graduate School of Medicine, Chiba University, Chiba [2] Department of Pediatrics, National Hospital Organization, Shimoshizu Hospital, Chiba
| | - Akio Matsumoto
- Department of Pharmacology, Graduate School of Medicine, Chiba University, Chiba
| | - Naoki Shimojo
- Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yoichi Kohno
- Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Haruaki Nakaya
- Department of Pharmacology, Graduate School of Medicine, Chiba University, Chiba
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44
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New Strategies for the Treatment of Phenylketonuria (PKU). Metabolites 2014; 4:1007-17. [PMID: 25375236 PMCID: PMC4279156 DOI: 10.3390/metabo4041007] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 10/27/2014] [Accepted: 10/30/2014] [Indexed: 12/19/2022] Open
Abstract
Phenylketonuria (PKU) was the first inherited metabolic disease in which dietary treatment was found to prevent the disease's clinical features. Treatment of phenylketonuria remains difficult due to progressive decrease in adherence to diet and the presence of neurocognitive defects despite therapy. This review aims to summarize the current literature on new treatment strategies. Additions to treatment include new, more palatable foods based on glycomacropeptide that contains very limited amount of aromatic amino acids, the administration of large neutral amino acids to prevent phenylalanine entry into the brain or tetrahydropterina cofactor capable of increasing residual activity of phenylalanine hydroxylase. Moreover, human trials have recently been performed with subcutaneous administration of phenylalanine ammonia-lyase, and further efforts are underway to develop an oral therapy containing phenylanine ammonia-lyase. Gene therapy also seems to be a promising approach in the near future.
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45
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Hagedorn TS, van Berkel P, Hammerschmidt G, Lhotáková M, Saludes RP. Requirements for a minimum standard of care for phenylketonuria: the patients' perspective. Orphanet J Rare Dis 2013; 8:191. [PMID: 24341788 PMCID: PMC3878574 DOI: 10.1186/1750-1172-8-191] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 11/12/2013] [Indexed: 11/22/2022] Open
Abstract
Phenylketonuria (PKU, ORPHA716) is an inherited disorder that affects about one in every 10,000 children born in Europe. Early and continuous application of a modified diet is largely successful in preventing the devastating brain damage associated with untreated PKU. The management of PKU is inconsistent: there are few national guidelines, and these tend to be incomplete and implemented sporadically. In this article, the first-ever pan- European patient/carer perspective on optimal PKU care, the European Society for Phenylketonuria and Allied Disorders (E.S.PKU) proposes recommendations for a minimum standard of care for PKU, to underpin the development of new pan-European guideline for the management of PKU. New standards of best practice should guarantee equal access to screening, treatment and monitoring throughout Europe. Screening protocols and interpretation of screening results should be standardised. Experienced Centres of Expertise are required, in line with current European Union policy, to guarantee a defined standard of multidisciplinary treatment and care for all medical and social aspects of PKU. Women of childbearing age require especially intensive management, due to the risk of severe risks to the foetus conferred by uncontrolled PKU. All aspects of treatment should be reimbursed to ensure uniform access across Europe to guideline-driven, evidence-based care. The E.S.PKU urges PKU healthcare professionals caring for people with PKU to take the lead in developing evidence based guidelines on PKU, while continuing to play an active role in serving as the voice of patients and their families, whose lives are affected by the condition.
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Affiliation(s)
- Tobias S Hagedorn
- European Society for Phenylketonuria and Allied Disorders (E,S,PKU), Melsele, Belgium.
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46
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de Groot MJ, Hoeksma M, Reijngoud DJ, de Valk HW, Paans AMJ, Sauer PJJ, van Spronsen FJ. Phenylketonuria: reduced tyrosine brain influx relates to reduced cerebral protein synthesis. Orphanet J Rare Dis 2013; 8:133. [PMID: 24007597 PMCID: PMC3847152 DOI: 10.1186/1750-1172-8-133] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 08/21/2013] [Indexed: 11/25/2022] Open
Abstract
Background In phenylketonuria (PKU), elevated blood phenylalanine (Phe) concentrations are considered to impair transport of large neutral amino acids (LNAAs) from blood to brain. This impairment is believed to underlie cognitive deficits in PKU via different mechanisms, including reduced cerebral protein synthesis. In this study, we investigated the hypothesis that impaired LNAA influx relates to reduced cerebral protein synthesis. Methods Using positron emission tomography, L-[1-11C]-tyrosine (11C-Tyr) brain influx and incorporation into cerebral protein were studied in 16 PKU patients (median age 24, range 16 – 47 years), most of whom were early and continuously treated. Data were analyzed by regression analyses, using either 11C-Tyr brain influx or 11C-Tyr cerebral protein incorporation as outcome variable. Predictor variables were baseline plasma Phe concentration, Phe tolerance, age, and 11C-Tyr brain efflux. For the modelling of cerebral protein incorporation, 11C-Tyr brain influx was added as a predictor variable. Results 11C-Tyr brain influx was inversely associated with plasma Phe concentrations (median 512, range 233 – 1362 μmol/L; delta adjusted R2=0.571, p=0.013). In addition, 11C-Tyr brain influx was positively associated with 11C-Tyr brain efflux (delta adjusted R2=0.098, p=0.041). Cerebral protein incorporation was positively associated with 11C-Tyr brain influx (adjusted R2=0.567, p<0.001). All additional associations between predictor and outcome variables were statistically nonsignificant. Conclusions Our data favour the hypothesis that an elevated concentration of Phe in blood reduces cerebral protein synthesis by impairing LNAA transport from blood to brain. Considering the importance of cerebral protein synthesis for adequate brain development and functioning, our results support the notion that PKU treatment be continued in adulthood. Future studies investigating the effects of impaired LNAA transport on cerebral protein synthesis in more detail are indicated.
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Affiliation(s)
- Martijn J de Groot
- Department of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
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Nazi S, Rohani F, Sajedi F, Biglarian A, Setoodeh A. Motor development skills of 1- to 4-year-old Iranian children with early treated phenylketonuria. JIMD Rep 2013; 12:85-9. [PMID: 23918467 DOI: 10.1007/8904_2013_248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/24/2013] [Accepted: 06/25/2013] [Indexed: 03/07/2023] Open
Abstract
Objective : To gauge the gross and fine motor development of early treated phenylketonuria (ETPKU) in children in the age range of 1-4 years. Methods : A cross-sectional analytic study was conducted in PKU clinics (reference clinics for PKU follow-up), Tehran, Iran. Seventy children with ETPKU were selected as the case group for the study. ETPKU children were those with early and continuous treatment with a phenylalanine-restricted diet (the mean of blood phenylalanine level during the recent 6 months was 2-6 mg/dL or 120-360 μmol/L). Also, 100 healthy and normal children matched with the ETPKU group for age were randomly selected from 4 kindergartens in four parts of Tehran as a control group. The measurements consisted of a demographic questionnaire, Peabody Developmental Motor Scale-2 (PDMS-2), and pediatrician assessment. Motor quotients were determined by PDMS-2 and then compared in both groups by two independent samples t-test. Results : The mean ages in case and control group were 28.5 (± 11.6) and 29.7 (± 11.3) months, respectively. Comparison of the mean fine, gross, and total developmental motor quotients (DMQs) showed statistically significant differences between the two groups (p < 0.05). The fine and total DMQs of ETPKU children were also correlated with age. In addition, there was a negative correlation between the phenylalanine level and fine (p < 0.001) and total (p = 0.001) DMQs. Conclusion : It seems that ETPKU Iranian children, regardless of following a phenylalanine-restricted diet or not, have lower motor development. It is recommended to plan programs for early detection and intervention of developmental delays in these children.
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Affiliation(s)
- Sepideh Nazi
- Occupational therapy Department, Tehran University of Medical Sciences (TUMS), Tehran, Iran
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Walterfang M, Bonnot O, Mocellin R, Velakoulis D. The neuropsychiatry of inborn errors of metabolism. J Inherit Metab Dis 2013; 36:687-702. [PMID: 23700255 DOI: 10.1007/s10545-013-9618-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 04/29/2013] [Accepted: 04/30/2013] [Indexed: 12/15/2022]
Abstract
A number of metabolic disorders that affect the central nervous system can present in childhood, adolescence or adulthood as a phenocopy of a major psychiatric syndrome such as psychosis, depression, anxiety or mania. An understanding and awareness of secondary syndromes in metabolic disorders is of great importance as it can lead to the early diagnosis of such disorders. Many of these metabolic disorders are progressive and may have illness-modifying treatments available. Earlier diagnosis may prevent or delay damage to the central nervous system and allow for the institution of appropriate treatment and family and genetic counselling. Metabolic disorders appear to result in neuropsychiatric illness either through disruption of late neurodevelopmental processes (metachromatic leukodystrophy, adrenoleukodystrophy, GM2 gangliosidosis, Niemann-Pick type C, cerebrotendinous xanthomatosis, neuronal ceroid lipofuscinosis, and alpha mannosidosis) or via chronic or acute disruption of excitatory/inhibitory or monoaminergic neurotransmitter systems (acute intermittent porphyria, maple syrup urine disease, urea cycle disorders, phenylketonuria and disorders of homocysteine metabolism). In this manuscript we review the evidence for neuropsychiatric illness in major metabolic disorders and discuss the possible models for how these disorders result in psychiatric symptoms. Treatment considerations are discussed, including treatment resistance, the increased propensity for side-effects and the possibility of some treatments worsening the underlying disorder.
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Affiliation(s)
- Mark Walterfang
- Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Parkville, Australia.
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Yano S, Moseley K, Azen C. Large neutral amino acid supplementation increases melatonin synthesis in phenylketonuria: a new biomarker. J Pediatr 2013; 162:999-1003. [PMID: 23164313 PMCID: PMC8803270 DOI: 10.1016/j.jpeds.2012.10.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 08/30/2012] [Accepted: 10/08/2012] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To determine whether levels of melatonin in blood and urine can serve as a peripheral biomarker to reflect brain serotonin synthesis in individuals with phenylketonuria (PKU). STUDY DESIGN We measured the levels of melatonin, a serotonin metabolite in the pinealocytes, in the blood and urine of individuals with PKU in a randomized double-blind placebo controlled crossover study consisting of three 3-week phases in 10 adults with PKU: phase 1 (washout), phase 2 (supplementation of large neutral amino acid [LNAA] tablets or placebo), and phase 3 (alternate supplementation). An overnight protocol to measure blood melatonin and urine 6-sulfatoxymelatonin and dopamine in first void urine specimens was conducted after each phase for subjects with PKU and once in 10 controls. RESULTS Significantly lower concentrations of these neurotransmitter metabolites were observed in subjects with PKU after phase 1 compared with controls (serum melatonin P = .008, urine melatonin P = .0043, urine dopamine P < .0001), with significant increases after LNAA supplementation compared with the placebo phase (serum melatonin P = .0008, urine melatonin P = .0008, urine dopamine P = .0005). The mean tryptophan/LNAA and tyrosine/LNAA ratios were markedly lower in subjects with PKU compared with controls, and these ratios were significantly increased in the LNAA phase compared with the placebo phase (P = .016, P = .0003, respectively). Blood phenylalanine levels in subjects with PKU were not significantly different between placebo and LNAA phases (P = .74). CONCLUSION Blood and urine melatonin levels may serve as biomarkers reflecting brain serotonin synthesis in subjects with PKU. Because this cannot be evaluated using blood phenylalanine levels, it may provide information on neurotransmitter metabolism for optimal dietary management.
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Affiliation(s)
- Shoji Yano
- Genetics Division, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
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50
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The Assay of Enzyme Activity by Positron Emission Tomography. MOLECULAR IMAGING IN THE CLINICAL NEUROSCIENCES 2012. [DOI: 10.1007/7657_2012_53] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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