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Schwantje M, Ebberink MS, Doolaard M, Ruiter JPN, Fuchs SA, Darin N, Hedberg‐Oldfors C, Régal L, Donker Kaat L, Huidekoper HH, Olpin S, Cole D, Moat SJ, Visser G, Ferdinandusse S. Thermo-sensitive mitochondrial trifunctional protein deficiency presenting with episodic myopathy. J Inherit Metab Dis 2022; 45:819-831. [PMID: 35403730 PMCID: PMC9542805 DOI: 10.1002/jimd.12503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/24/2022] [Accepted: 04/07/2022] [Indexed: 11/29/2022]
Abstract
Mitochondrial trifunctional protein (MTP) is involved in long-chain fatty acid β-oxidation (lcFAO). Deficiency of one or more of the enzyme activities as catalyzed by MTP causes generalized MTP deficiency (MTPD), long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), or long-chain ketoacyl-CoA thiolase deficiency (LCKATD). When genetic variants result in thermo-sensitive enzymes, increased body temperature (e.g. fever) can reduce enzyme activity and be a risk factor for clinical decompensation. This is the first description of five patients with a thermo-sensitive MTP deficiency. Clinical and genetic information was obtained from clinical files. Measurement of LCHAD and LCKAT activities, lcFAO-flux studies and palmitate loading tests were performed in skin fibroblasts cultured at 37°C and 40°C. In all patients (four MTPD, one LCKATD), disease manifested during childhood (manifestation age: 2-10 years) with myopathic symptoms triggered by fever or exercise. In four patients, signs of retinopathy or neuropathy were present. Plasma long-chain acylcarnitines were normal or slightly increased. HADHB variants were identified (at age: 6-18 years) by whole exome sequencing or gene panel analyses. At 37°C, LCHAD and LCKAT activities were mildly impaired and lcFAO-fluxes were normal. Remarkably, enzyme activities and lcFAO-fluxes were markedly diminished at 40°C. Preventive (dietary) measures improved symptoms for most. In conclusion, all patients with thermo-sensitive MTP deficiency had a long diagnostic trajectory and both genetic and enzymatic testing were required for diagnosis. The frequent absence of characteristic acylcarnitine abnormalities poses a risk for a diagnostic delay. Given the positive treatment effects, upfront genetic screening may be beneficial to enhance early recognition.
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Affiliation(s)
- Marit Schwantje
- Department of Metabolic DiseasesWilhelmina Children's Hospital, University Medical Center UtrechtUtrechtThe Netherlands
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Merel S. Ebberink
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Mirjam Doolaard
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Jos P. N. Ruiter
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Sabine A. Fuchs
- Department of Metabolic DiseasesWilhelmina Children's Hospital, University Medical Center UtrechtUtrechtThe Netherlands
| | - Niklas Darin
- Department of Pediatrics, Institute of Clinical Sciences, Sahlgrenska AcademyUniversity of Gothenburg, Sahlgrenska University HospitalGothenburgSweden
| | - Carola Hedberg‐Oldfors
- Department of Laboratory Medicine, Institute of BiomedicineUniversity of GothenburgGothenburgSweden
| | - Luc Régal
- Pediatric Neurology and Metabolism Department of PediatricsUZ BrusselJetteBelgium
| | - Laura Donker Kaat
- Department of Clinical Genetics, Erasmus MCUniversity Medical Center RotterdamRotterdamThe Netherlands
| | - Hidde H. Huidekoper
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MCUniversity Medical Center RotterdamRotterdamThe Netherlands
| | - Simon Olpin
- Department of Clinical ChemistrySheffield Children's HospitalSheffieldUK
| | - Duncan Cole
- Wales Newborn Screening Laboratory, Department of Medical Biochemistry, Immunology and ToxicologyUniversity Hospital of WalesCardiffUK
- School of MedicineCardiff UniversityCardiffUK
| | - Stuart J. Moat
- Department of Clinical ChemistrySheffield Children's HospitalSheffieldUK
- Wales Newborn Screening Laboratory, Department of Medical Biochemistry, Immunology and ToxicologyUniversity Hospital of WalesCardiffUK
| | - Gepke Visser
- Department of Metabolic DiseasesWilhelmina Children's Hospital, University Medical Center UtrechtUtrechtThe Netherlands
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
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2
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Sasarman F, Ferdinandusse S, Sinasac DS, Fung E, Sparkes R, Reeves M, Rombough C, Sass JO, Voit R, Ruiter JPN, Koster J, Waterham HR, Pasquini E, Donati MA, Marquardt T, Wanders RJA, Al-Hertani W. 3-Hydroxyisobutyric acid dehydrogenase deficiency: Expanding the clinical spectrum and quantitation of D- and L-3-Hydroxyisobutyric acid by an LC-MS/MS method. J Inherit Metab Dis 2022; 45:445-455. [PMID: 35174513 DOI: 10.1002/jimd.12486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/11/2022] [Accepted: 02/15/2022] [Indexed: 11/11/2022]
Abstract
A deficiency of 3-hydroxyisobutyric acid dehydrogenase (HIBADH) has been recently identified as a cause of primary 3-hydroxyisobutyric aciduria in two siblings; the only previously recognized primary cause had been a deficiency of methylmalonic semialdehyde dehydrogenase, the enzyme that is immediately downstream of HIBADH in the valine catabolic pathway and is encoded by the ALDH6A1 gene. Here we report on three additional patients from two unrelated families who present with marked and persistent elevations of urine L-3-hydroxyisobutyric acid (L-3HIBA) and a range of clinical findings. Molecular genetic analyses revealed novel, homozygous variants in the HIBADH gene that are private within each family. Evidence for pathogenicity of the identified variants is presented, including enzymatic deficiency of HIBADH in patient fibroblasts. This report describes new variants in HIBADH as an underlying cause of primary 3-hydroxyisobutyric aciduria and expands the clinical spectrum of this recently identified inborn error of valine metabolism. Additionally, we describe a quantitative method for the measurement of D- and L-3HIBA in plasma and urine and present the results of a valine restriction therapy in one of the patients.
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Affiliation(s)
- Florin Sasarman
- Department of Medical Genetics, Cummings School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Biochemical Genetics Laboratory, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands
| | - David S Sinasac
- Department of Medical Genetics, Cummings School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Biochemical Genetics Laboratory, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Ernest Fung
- Biochemical Genetics Laboratory, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Rebecca Sparkes
- Department of Medical Genetics, Cummings School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Melanie Reeves
- Nutrition and Food Services, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Catherine Rombough
- Nutrition and Food Services, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Jörn Oliver Sass
- Inborn Errors of Metabolism, Department of Natural Sciences, Bonn-Rhein- Sieg University of Applied Sciences, Rheinbach, Germany
- Instititute for Functional Gene Analytics (IFGA), Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany
| | - Renate Voit
- Inborn Errors of Metabolism, Department of Natural Sciences, Bonn-Rhein- Sieg University of Applied Sciences, Rheinbach, Germany
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Janet Koster
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Elisabetta Pasquini
- Metabolic Unit and Newborn Screening, Department of Neuroscience, Meyer Children's Hospital, Florence, Italy
| | - Maria A Donati
- Metabolic Unit and Newborn Screening, Department of Neuroscience, Meyer Children's Hospital, Florence, Italy
| | - Thorsten Marquardt
- Department of General Pediatrics, University Children's Hospital Münster, Münster, Germany
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Walla Al-Hertani
- Department of Pediatrics, Harvard Medical School and Boston Children's Hospital, Boston, Massachusetts, USA
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3
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Ferdinandusse S, McWalter K, Te Brinke H, IJlst L, Mooijer PM, Ruiter JPN, van Lint AEM, Pras-Raves M, Wever E, Millan F, Guillen Sacoto MJ, Begtrup A, Tarnopolsky M, Brady L, Ladda RL, Sell SL, Nowak CB, Douglas J, Tian C, Ulm E, Perlman S, Drack AV, Chong K, Martin N, Brault J, Brokamp E, Toro C, Gahl WA, Macnamara EF, Wolfe L, Waisfisz Q, Zwijnenburg PJG, Ziegler A, Barth M, Smith R, Ellingwood S, Gaebler-Spira D, Bakhtiari S, Kruer MC, van Kampen AHC, Wanders RJA, Waterham HR, Cassiman D, Vaz FM. Correction to: An autosomal dominant neurological disorder caused by de novo variants in FAR1 resulting in uncontrolled synthesis of ether lipids. Genet Med 2021; 23:2467. [PMID: 34667295 PMCID: PMC8629751 DOI: 10.1038/s41436-021-01189-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands.
| | | | - Heleen Te Brinke
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Petra M Mooijer
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Alida E M van Lint
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Mia Pras-Raves
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
- Core Facility Metabolomics, Amsterdam UMC, Amsterdam, The Netherlands
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Eric Wever
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
- Core Facility Metabolomics, Amsterdam UMC, Amsterdam, The Netherlands
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | | | | | | | - Mark Tarnopolsky
- Department of Pediatrics, McMaster University Children's Hospital, Hamilton, ON, Canada
| | - Lauren Brady
- Department of Pediatrics, McMaster University Children's Hospital, Hamilton, ON, Canada
| | - Roger L Ladda
- Department of Pediatrics, Penn State Children's Hospital, Hershey, PA, USA
| | - Susan L Sell
- Department of Pediatrics, Penn State Children's Hospital, Hershey, PA, USA
| | - Catherine B Nowak
- The Feingold Center for Children, Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Jessica Douglas
- The Feingold Center for Children, Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Cuixia Tian
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Elizabeth Ulm
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Seth Perlman
- Department of Neurology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | - Arlene V Drack
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Karen Chong
- Mount Sinai Hospital, Department of Obstetrics and Gynecology, Prenatal Diagnosis and Medical Genetics Program, Toronto, ON, Canada
| | - Nicole Martin
- Mount Sinai Hospital, Department of Obstetrics and Gynecology, Prenatal Diagnosis and Medical Genetics Program, Toronto, ON, Canada
| | - Jennifer Brault
- Vanderbilt University Medical Center, Department of Pediatrics, Nashville, TN, USA
| | - Elly Brokamp
- Vanderbilt University Medical Center, Department of Pediatrics, Nashville, TN, USA
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Ellen F Macnamara
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Lynne Wolfe
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Quinten Waisfisz
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Petra J G Zwijnenburg
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Alban Ziegler
- Genetic department, University Hospital Angers, Angers, France
| | - Magalie Barth
- Genetic department, University Hospital Angers, Angers, France
| | - Rosemarie Smith
- Division of Genetics, Department of Pediatrics, Maine Medical Center, Portland, ME, USA
| | - Sara Ellingwood
- Division of Genetics, Department of Pediatrics, Maine Medical Center, Portland, ME, USA
| | - Deborah Gaebler-Spira
- Feinberg Northwestern University School of Medicine, Shirley Ryan Ability Lab, Chicago, IL, USA
| | - Somayeh Bakhtiari
- Barrow Neurological Institute, Phoenix Children's Hospital and University of Arizona College of Medicine, Phoenix, AZ, USA
| | - Michael C Kruer
- Barrow Neurological Institute, Phoenix Children's Hospital and University of Arizona College of Medicine, Phoenix, AZ, USA
| | - Antoine H C van Kampen
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - David Cassiman
- Department of Gastroenterology-Hepatology, Metabolic Center, University Hospitals Leuven, Leuven, Belgium
| | - Frédéric M Vaz
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands.
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4
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Ferdinandusse S, McWalter K, Te Brinke H, IJlst L, Mooijer PM, Ruiter JPN, van Lint AEM, Pras-Raves M, Wever E, Millan F, Guillen Sacoto MJ, Begtrup A, Tarnopolsky M, Brady L, Ladda RL, Sell SL, Nowak CB, Douglas J, Tian C, Ulm E, Perlman S, Drack AV, Chong K, Martin N, Brault J, Brokamp E, Toro C, Gahl WA, Macnamara EF, Wolfe L, Waisfisz Q, Zwijnenburg PJG, Ziegler A, Barth M, Smith R, Ellingwood S, Gaebler-Spira D, Bakhtiari S, Kruer MC, van Kampen AHC, Wanders RJA, Waterham HR, Cassiman D, Vaz FM. An autosomal dominant neurological disorder caused by de novo variants in FAR1 resulting in uncontrolled synthesis of ether lipids. Genet Med 2021; 23:740-750. [PMID: 33239752 PMCID: PMC8026396 DOI: 10.1038/s41436-020-01027-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 10/15/2020] [Accepted: 10/21/2020] [Indexed: 12/25/2022] Open
Abstract
PURPOSE In this study we investigate the disease etiology in 12 patients with de novo variants in FAR1 all resulting in an amino acid change at position 480 (p.Arg480Cys/His/Leu). METHODS Following next-generation sequencing and clinical phenotyping, functional characterization was performed in patients' fibroblasts using FAR1 enzyme analysis, FAR1 immunoblotting/immunofluorescence, and lipidomics. RESULTS All patients had spastic paraparesis and bilateral congenital/juvenile cataracts, in most combined with speech and gross motor developmental delay and truncal hypotonia. FAR1 deficiency caused by biallelic variants results in defective ether lipid synthesis and plasmalogen deficiency. In contrast, patients' fibroblasts with the de novo FAR1 variants showed elevated plasmalogen levels. Further functional studies in fibroblasts showed that these variants cause a disruption of the plasmalogen-dependent feedback regulation of FAR1 protein levels leading to uncontrolled ether lipid production. CONCLUSION Heterozygous de novo variants affecting the Arg480 residue of FAR1 lead to an autosomal dominant disorder with a different disease mechanism than that of recessive FAR1 deficiency and a diametrically opposed biochemical phenotype. Our findings show that for patients with spastic paraparesis and bilateral cataracts, FAR1 should be considered as a candidate gene and added to gene panels for hereditary spastic paraplegia, cerebral palsy, and juvenile cataracts.
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Affiliation(s)
- Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands.
| | | | - Heleen Te Brinke
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Petra M Mooijer
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Alida E M van Lint
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Mia Pras-Raves
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
- Core Facility Metabolomics, Amsterdam UMC, Amsterdam, The Netherlands
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Eric Wever
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
- Core Facility Metabolomics, Amsterdam UMC, Amsterdam, The Netherlands
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | | | | | | | - Mark Tarnopolsky
- Department of Pediatrics, McMaster University Children's Hospital, Hamilton, ON, Canada
| | - Lauren Brady
- Department of Pediatrics, McMaster University Children's Hospital, Hamilton, ON, Canada
| | - Roger L Ladda
- Department of Pediatrics, Penn State Children's Hospital, Hershey, PA, USA
| | - Susan L Sell
- Department of Pediatrics, Penn State Children's Hospital, Hershey, PA, USA
| | - Catherine B Nowak
- The Feingold Center for Children, Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Jessica Douglas
- The Feingold Center for Children, Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Cuixia Tian
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Elizabeth Ulm
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Seth Perlman
- Department of Neurology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | - Arlene V Drack
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Karen Chong
- Mount Sinai Hospital, Department of Obstetrics and Gynecology, Prenatal Diagnosis and Medical Genetics Program, Toronto, ON, Canada
| | - Nicole Martin
- Mount Sinai Hospital, Department of Obstetrics and Gynecology, Prenatal Diagnosis and Medical Genetics Program, Toronto, ON, Canada
| | - Jennifer Brault
- Vanderbilt University Medical Center, Department of Pediatrics, Nashville, TN, USA
| | - Elly Brokamp
- Vanderbilt University Medical Center, Department of Pediatrics, Nashville, TN, USA
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Ellen F Macnamara
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Lynne Wolfe
- NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Quinten Waisfisz
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Petra J G Zwijnenburg
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Alban Ziegler
- Genetic department, University Hospital Angers, Angers, France
| | - Magalie Barth
- Genetic department, University Hospital Angers, Angers, France
| | - Rosemarie Smith
- Division of Genetics, Department of Pediatrics, Maine Medical Center, Portland, ME, USA
| | - Sara Ellingwood
- Division of Genetics, Department of Pediatrics, Maine Medical Center, Portland, ME, USA
| | - Deborah Gaebler-Spira
- Feinberg Northwestern University School of Medicine, Shirley Ryan Ability Lab, Chicago, IL, USA
| | - Somayeh Bakhtiari
- Barrow Neurological Institute, Phoenix Children's Hospital and University of Arizona College of Medicine, Phoenix, AZ, USA
| | - Michael C Kruer
- Barrow Neurological Institute, Phoenix Children's Hospital and University of Arizona College of Medicine, Phoenix, AZ, USA
| | - Antoine H C van Kampen
- Bioinformatics Laboratory, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands
| | - David Cassiman
- Department of Gastroenterology-Hepatology, Metabolic Center, University Hospitals Leuven, Leuven, Belgium
| | - Frédéric M Vaz
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, The Netherlands.
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5
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Vaz FM, McDermott JH, Alders M, Wortmann SB, Kölker S, Pras-Raves ML, Vervaart MAT, van Lenthe H, Luyf ACM, Elfrink HL, Metcalfe K, Cuvertino S, Clayton PE, Yarwood R, Lowe MP, Lovell S, Rogers RC, van Kampen AHC, Ruiter JPN, Wanders RJA, Ferdinandusse S, van Weeghel M, Engelen M, Banka S. Mutations in PCYT2 disrupt etherlipid biosynthesis and cause a complex hereditary spastic paraplegia. Brain 2020; 142:3382-3397. [PMID: 31637422 PMCID: PMC6821184 DOI: 10.1093/brain/awz291] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 06/07/2019] [Accepted: 07/16/2019] [Indexed: 11/14/2022] Open
Abstract
CTP:phosphoethanolamine cytidylyltransferase (ET), encoded by PCYT2, is the rate-limiting enzyme for phosphatidylethanolamine synthesis via the CDP-ethanolamine pathway. Phosphatidylethanolamine is one of the most abundant membrane lipids and is particularly enriched in the brain. We identified five individuals with biallelic PCYT2 variants clinically characterized by global developmental delay with regression, spastic para- or tetraparesis, epilepsy and progressive cerebral and cerebellar atrophy. Using patient fibroblasts we demonstrated that these variants are hypomorphic, result in altered but residual ET protein levels and concomitant reduced enzyme activity without affecting mRNA levels. The significantly better survival of hypomorphic CRISPR-Cas9 generated pcyt2 zebrafish knockout compared to a complete knockout, in conjunction with previously described data on the Pcyt2 mouse model, indicates that complete loss of ET function may be incompatible with life in vertebrates. Lipidomic analysis revealed profound lipid abnormalities in patient fibroblasts impacting both neutral etherlipid and etherphospholipid metabolism. Plasma lipidomics studies also identified changes in etherlipids that have the potential to be used as biomarkers for ET deficiency. In conclusion, our data establish PCYT2 as a disease gene for a new complex hereditary spastic paraplegia and confirm that etherlipid homeostasis is important for the development and function of the brain.
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Affiliation(s)
- Frédéric M Vaz
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - John H McDermott
- Manchester Centre for Genomics Medicine, St Mary's Hospital, Manchester University Hospital Foundation Trust, Health Innovation Manchester, Oxford Road, Manchester, UK
| | - Mariëlle Alders
- Laboratory Genome Diagnostics, Amsterdam UMC, University of Amsterdam, Department of Clinical Genetics, Amsterdam Reproduction and Development, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Saskia B Wortmann
- Institute of Human Genetics, Technical University München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.,University Children's Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Stefan Kölker
- Division of Pediatric Neurology and Metabolic Medicine, Centre for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Mia L Pras-Raves
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands.,Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health research institute, Amsterdam UMC, University of Amsterdam, Amsterdam AZ, The Netherlands
| | - Martin A T Vervaart
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Henk van Lenthe
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Angela C M Luyf
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health research institute, Amsterdam UMC, University of Amsterdam, Amsterdam AZ, The Netherlands
| | - Hyung L Elfrink
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Kay Metcalfe
- Manchester Centre for Genomics Medicine, St Mary's Hospital, Manchester University Hospital Foundation Trust, Health Innovation Manchester, Oxford Road, Manchester, UK
| | - Sara Cuvertino
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Peter E Clayton
- Department of Pediatric Endocrinology, Royal Manchester Children's Hospital, Manchester University Hospital Foundation Trust, Oxford Road, Manchester, UK
| | - Rebecca Yarwood
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Martin P Lowe
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Simon Lovell
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Richard C Rogers
- Greenwood Genetic Center, 14 Edgewood Drive, Greenville, SC, USA
| | | | - Antoine H C van Kampen
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health research institute, Amsterdam UMC, University of Amsterdam, Amsterdam AZ, The Netherlands.,Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, XH Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Michel van Weeghel
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Marc Engelen
- Department of (Pediatric) Neurology, Emma Children's Hospital, Amsterdam UMC, Amsterdam, The Netherlands
| | - Siddharth Banka
- Manchester Centre for Genomics Medicine, St Mary's Hospital, Manchester University Hospital Foundation Trust, Health Innovation Manchester, Oxford Road, Manchester, UK.,Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
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6
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Welsink-Karssies MM, van Weeghel M, Hollak CEM, Elfrink HL, Janssen MCH, Lai K, Langendonk JG, Oussoren E, Ruiter JPN, Treacy EP, de Vries M, Ferdinandusse S, Bosch AM. The Galactose Index measured in fibroblasts of GALT deficient patients distinguishes variant patients detected by newborn screening from patients with classical phenotypes. Mol Genet Metab 2020; 129:171-176. [PMID: 31954591 DOI: 10.1016/j.ymgme.2020.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 11/18/2022]
Abstract
BACKGROUND The high variability in clinical outcome of patients with Classical Galactosemia (CG) is poorly understood and underlines the importance of prognostic biomarkers, which are currently lacking. The aim of this study was to investigate if residual galactose metabolism capacity is associated with clinical and biochemical outcomes in CG patients with varying geno- and phenotypes. METHODS Galactose Metabolite Profiling (GMP) was used to determine residual galactose metabolism in fibroblasts of CG patients. The association between the galactose index (GI) defined as the ratio of the measured metabolites [U13C]Gal-1-P/ [13C6]UDP-galactose, and both intellectual and neurological outcome and galactose-1-phosphate (Gal-1-P) levels was investigated. RESULTS GMP was performed in fibroblasts of 28 patients and 3 control subjects. The GI of the classical phenotype patients (n = 22) was significantly higher than the GI of four variant patients detected by newborn screening (NBS) (p = .002), two homozygous p.Ser135Leu patients (p = .022) and three controls (p = .006). In the classical phenotype patients, 13/18 (72%) had a poor intellectual outcome (IQ < 85) and 6/12 (50%) had a movement disorder. All the NBS detected variant patients (n = 4) had a normal intellectual outcome (IQ ≥ 85) and none of them has a movement disorder. In the classical phenotype patients, there was no significant difference in GI between patients with a poor and normal clinical outcome. The NBS detected variant patients had significantly lower GI levels and thus higher residual galactose metabolism than patients with classical phenotypes. There was a clear correlation between Gal-1-P levels in erythrocytes and the GI (p = .001). CONCLUSIONS The GI was able to distinguish CG patients with varying geno- and phenotypes and correlated with Gal-1-P. The data of the NBS detected variant patients demonstrated that a higher residual galactose metabolism may result in a more favourable clinical outcome. Further research is needed to enable individual prognostication and treatment in all CG patients.
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Affiliation(s)
- Mendy M Welsink-Karssies
- Department of Pediatrics, Division of Metabolic Disorders, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Michel van Weeghel
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Core Facility Metabolomics, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Carla E M Hollak
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Hyung L Elfrink
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Core Facility Metabolomics, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Mirian C H Janssen
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Kent Lai
- Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, United States
| | - Janneke G Langendonk
- Department of Internal Medicine, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Esmee Oussoren
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Jos P N Ruiter
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Eileen P Treacy
- National Centre for Inherited Metabolic Disorders, The Mater Misericordiae University Hospital Dublin, Ireland
| | - Maaike de Vries
- Department of Pediatrics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Sacha Ferdinandusse
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Annet M Bosch
- Department of Pediatrics, Division of Metabolic Disorders, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.
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7
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van Rijt WJ, Ferdinandusse S, Giannopoulos P, Ruiter JPN, de Boer L, Bosch AM, Huidekoper HH, Rubio-Gozalbo ME, Visser G, Williams M, Wanders RJA, Derks TGJ. Prediction of disease severity in multiple acyl-CoA dehydrogenase deficiency: A retrospective and laboratory cohort study. J Inherit Metab Dis 2019; 42:878-889. [PMID: 31268564 DOI: 10.1002/jimd.12147] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/24/2019] [Accepted: 07/01/2019] [Indexed: 12/16/2022]
Abstract
Multiple acyl-CoA dehydrogenase deficiency (MADD) is an ultra-rare inborn error of mitochondrial fatty acid oxidation (FAO) and amino acid metabolism. Individual phenotypes and treatment response can vary markedly. We aimed to identify markers that predict MADD phenotypes. We performed a retrospective nationwide cohort study; then developed an MADD-disease severity scoring system (MADD-DS3) based on signs and symptoms with weighed expert opinions; and finally correlated phenotypes and MADD-DS3 scores to FAO flux (oleate and myristate oxidation rates) and acylcarnitine profiles after palmitate loading in fibroblasts. Eighteen patients, diagnosed between 1989 and 2014, were identified. The MADD-DS3 entails enumeration of eight domain scores, which are calculated by averaging the relevant symptom scores. Lifetime MADD-DS3 scores of patients in our cohort ranged from 0 to 29. FAO flux and [U-13 C]C2-, C5-, and [U-13 C]C16-acylcarnitines were identified as key variables that discriminated neonatal from later onset patients (all P < .05) and strongly correlated to MADD-DS3 scores (oleate: r = -.86; myristate: r = -.91; [U-13 C]C2-acylcarnitine: r = -.96; C5-acylcarnitine: r = .97; [U-13 C]C16-acylcarnitine: r = .98, all P < .01). Functional studies in fibroblasts were found to differentiate between neonatal and later onset MADD-patients and were correlated to MADD-DS3 scores. Our data may improve early prediction of disease severity in order to start (preventive) and follow-up treatment appropriately. This is especially relevant in view of the inclusion of MADD in population newborn screening programs.
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Affiliation(s)
- Willemijn J van Rijt
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Sacha Ferdinandusse
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Panagiotis Giannopoulos
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Jos P N Ruiter
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Lonneke de Boer
- Department of Pediatrics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Annet M Bosch
- Department of Pediatrics, Division of Metabolic Disorders, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Hidde H Huidekoper
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - M Estela Rubio-Gozalbo
- Department of Pediatrics and Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Gepke Visser
- Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Monique Williams
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Ronald J A Wanders
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Terry G J Derks
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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8
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Ferdinandusse S, Te Brinke H, Ruiter JPN, Haasjes J, Oostheim W, van Lenthe H, IJlst L, Ebberink MS, Wanders RJA, Vaz FM, Waterham HR. A mutation creating an upstream translation initiation codon in SLC22A5 5'UTR is a frequent cause of primary carnitine deficiency. Hum Mutat 2019; 40:1899-1904. [PMID: 31187905 PMCID: PMC6790604 DOI: 10.1002/humu.23839] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/28/2019] [Accepted: 06/05/2019] [Indexed: 12/31/2022]
Abstract
Primary carnitine deficiency is caused by a defect in the active cellular uptake of carnitine by Na+ -dependent organic cation transporter novel 2 (OCTN2). Genetic diagnostic yield for this metabolic disorder has been relatively low, suggesting that disease-causing variants are missed. We Sanger sequenced the 5' untranslated region (UTR) of SLC22A5 in individuals with possible primary carnitine deficiency in whom no or only one mutant allele had been found. We identified a novel 5'-UTR c.-149G>A variant which we characterized by expression studies with reporter constructs in HeLa cells and by carnitine-transport measurements in fibroblasts using a newly developed sensitive assay based on tandem mass spectrometry. This variant, which we identified in 57 of 236 individuals of our cohort, introduces a functional upstream out-of-frame translation initiation codon. We show that the codon suppresses translation from the wild-type ATG of SLC22A5, resulting in reduced OCTN2 protein levels and concomitantly lower transport activity. With an allele frequency of 24.2% the c.-149G>A variant is the most frequent cause of primary carnitine deficiency in our cohort and may explain other reported cases with an incomplete genetic diagnosis. Individuals carrying this variant should be clinically re-evaluated and monitored to determine if this variant has clinical consequences.
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Affiliation(s)
- Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands.,United for Metabolic Diseases, The Netherlands
| | - Heleen Te Brinke
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Janet Haasjes
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Wendy Oostheim
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Henk van Lenthe
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - Merel S Ebberink
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands.,United for Metabolic Diseases, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands.,United for Metabolic Diseases, The Netherlands
| | - Frédéric M Vaz
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands.,United for Metabolic Diseases, The Netherlands
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism Research Institute, University of Amsterdam, Amsterdam, The Netherlands.,United for Metabolic Diseases, The Netherlands
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9
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Adam AAA, van der Mark VA, Ruiter JPN, Wanders RJA, Oude Elferink RPJ, Chamuleau RAFM, Hoekstra R. Overexpression of carbamoyl-phosphate synthase 1 significantly improves ureagenesis of human liver HepaRG cells only when cultured under shaking conditions. Mitochondrion 2019; 47:298-308. [PMID: 30802674 DOI: 10.1016/j.mito.2019.02.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 01/17/2019] [Accepted: 02/21/2019] [Indexed: 12/12/2022]
Abstract
Hyperammonemia is an important contributing factor to hepatic encephalopathy in end-stage liver failure patients. Therefore reducing hyperammonemia is a requisite of bioartificial liver support (BAL). Ammonia elimination by human liver HepaRG cells occurs predominantly through reversible fixation into amino acids, whereas the irreversible conversion into urea is limited. Compared to human liver, the expression and activity of the three urea cycle (UC) enzymes carbamoyl-phosphate synthase1 (CPS1), ornithine transcarbamoylase (OTC) and arginase1, are low. To improve HepaRG cells as BAL biocomponent, its rate limiting factor of the UC was determined under two culture conditions: static and dynamic medium flow (DMF) achieved by shaking. HepaRG cells increasingly converted escalating arginine doses into urea, indicating that arginase activity is not limiting ureagenesis. Neither was OTC activity, as a stable HepaRG line overexpressing OTC exhibited a 90- and 15.7-fold upregulation of OTC transcript and activity levels, without improvement in ureagenesis. However, a stable HepaRG line overexpressing CPS1 showed increased mitochondrial stress and reduced hepatic differentiation without promotion of the CPS1 transcript level or ureagenesis under static-culturing conditions, yet, it exhibited a 4.3-fold increased ureagenesis under DMF. This was associated with increased CPS1 transcript and activity levels amounting to >2-fold, increased mitochondrial abundance and hepatic differentiation. Unexpectedly, the transcript levels of several other UC genes increased up to 6.8-fold. We conclude that ureagenesis can be improved in HepaRG cells by CPS1 overexpression, however, only in combination with DMF-culturing, suggesting that both the low CPS1 level and static-culturing, possibly due to insufficient mitochondria, are limiting UC.
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Affiliation(s)
- Aziza A A Adam
- Amsterdam UMC, University of Amsterdam, Tytgat Institute for Liver and Intestinal Research, AG&M, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands
| | - Vincent A van der Mark
- Amsterdam UMC, University of Amsterdam, Tytgat Institute for Liver and Intestinal Research, AG&M, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands; Amsterdam UMC, University of Amsterdam, Surgical Laboratory, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Ronald P J Oude Elferink
- Amsterdam UMC, University of Amsterdam, Tytgat Institute for Liver and Intestinal Research, AG&M, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands
| | - Robert A F M Chamuleau
- Amsterdam UMC, University of Amsterdam, Tytgat Institute for Liver and Intestinal Research, AG&M, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands
| | - Ruurdtje Hoekstra
- Amsterdam UMC, University of Amsterdam, Tytgat Institute for Liver and Intestinal Research, AG&M, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands; Amsterdam UMC, University of Amsterdam, Surgical Laboratory, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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10
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Palir N, Ruiter JPN, Wanders RJA, Houtkooper RH. Identification of enzymes involved in oxidation of phenylbutyrate. J Lipid Res 2017; 58:955-961. [PMID: 28283530 PMCID: PMC5408614 DOI: 10.1194/jlr.m075317] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/08/2017] [Indexed: 02/03/2023] Open
Abstract
In recent years the short-chain fatty acid, 4-phenylbutyrate (PB), has emerged as a promising drug for various clinical conditions. In fact, PB has been Food and Drug Administration-approved for urea cycle disorders since 1996. PB is more potent and less toxic than its metabolite, phenylacetate (PA), and is not just a pro-drug for PA, as was initially assumed. The metabolic pathway of PB, however, has remained unclear. Therefore, we set out to identify the enzymes involved in the β-oxidation of PB. We used cells deficient in specific steps of fatty acid β-oxidation and ultra-HPLC to measure which enzymes were able to convert PB or its downstream products. We show that the first step in PB oxidation is catalyzed solely by the enzyme, medium-chain acyl-CoA dehydrogenase. The second (hydration) step can be catalyzed by all three mitochondrial enoyl-CoA hydratase enzymes, i.e., short-chain enoyl-CoA hydratase, long-chain enoyl-CoA hydratase, and 3-methylglutaconyl-CoA hydratase. Enzymes involved in the third step include both short- and long-chain 3-hydroxyacyl-CoA dehydrogenase. The oxidation of PB is completed by only one enzyme, i.e., long-chain 3-ketoacyl-CoA thiolase. Taken together, the enzymatic characteristics of the PB degradative pathway may lead to better dose finding and limiting the toxicity of this drug.
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Affiliation(s)
- Neža Palir
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Riekelt H Houtkooper
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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11
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Dercksen M, Duran M, IJlst L, Kulik W, Ruiter JPN, van Cruchten A, Tuchman M, Wanders RJA. A novel UPLC-MS/MS based method to determine the activity of N-acetylglutamate synthase in liver tissue. Mol Genet Metab 2016; 119:307-310. [PMID: 27771289 DOI: 10.1016/j.ymgme.2016.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 10/11/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND N-acetylglutamate synthase (NAGS) plays a key role in the removal of ammonia via the urea cycle by catalyzing the synthesis of N-acetylglutamate (NAG), the obligatory cofactor in the carbamyl phosphate synthetase 1 reaction. Enzymatic analysis of NAGS in liver homogenates has remained insensitive and inaccurate, which prompted the development of a novel method. METHODS UPLC-MS/MS was used in conjunction with stable isotope (N-acetylglutamic-2,3,3,4,4-d5 acid) dilution for the quantitative detection of NAG produced by the NAGS enzyme. The assay conditions were optimized using purified human NAGS and the optimized enzyme conditions were used to measure the activity in mouse liver homogenates. RESULTS A low signal-to-noise ratio in liver tissue samples was observed due to non-enzymatic formation of N-acetylglutamate and low specific activity, which interfered with quantitative analysis. Quenching of acetyl-CoA immediately after the incubation circumvented this analytical difficulty and allowed accurate and sensitive determination of mammalian NAGS activity. The specificity of the assay was validated by demonstrating a complete deficiency of NAGS in liver homogenates from Nags -/- mice. CONCLUSION The novel NAGS enzyme assay reported herein can be used for the diagnosis of inherited NAGS deficiency and may also be of value in the study of secondary hyperammonemia present in various inborn errors of metabolism as well as drug treatment.
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Affiliation(s)
- Marli Dercksen
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Human Metabonomics, North-West University, Potchefstroom Campus, South Africa.
| | - Marinus Duran
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Wim Kulik
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jos P N Ruiter
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arno van Cruchten
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Mendel Tuchman
- Children's National Medical Center, The George Washington University, Washington, DC, USA
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Departments of Pediatrics and Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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12
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Ferdinandusse S, Friederich MW, Burlina A, Ruiter JPN, Coughlin CR, Dishop MK, Gallagher RC, Bedoyan JK, Vaz FM, Waterham HR, Gowan K, Chatfield K, Bloom K, Bennett MJ, Elpeleg O, Van Hove JLK, Wanders RJA. Clinical and biochemical characterization of four patients with mutations in ECHS1. Orphanet J Rare Dis 2015; 10:79. [PMID: 26081110 PMCID: PMC4474341 DOI: 10.1186/s13023-015-0290-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 05/29/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Short-chain enoyl-CoA hydratase (SCEH, encoded by ECHS1) catalyzes hydration of 2-trans-enoyl-CoAs to 3(S)-hydroxy-acyl-CoAs. SCEH has a broad substrate specificity and is believed to play an important role in mitochondrial fatty acid oxidation and in the metabolism of branched-chain amino acids. Recently, the first patients with SCEH deficiency have been reported revealing only a defect in valine catabolism. We investigated the role of SCEH in fatty acid and branched-chain amino acid metabolism in four newly identified patients. In addition, because of the Leigh-like presentation, we studied enzymes involved in bioenergetics. METHODS Metabolite, enzymatic, protein and genetic analyses were performed in four patients, including two siblings. Palmitate loading studies in fibroblasts were performed to study mitochondrial β-oxidation. In addition, enoyl-CoA hydratase activity was measured with crotonyl-CoA, methacrylyl-CoA, tiglyl-CoA and 3-methylcrotonyl-CoA both in fibroblasts and liver to further study the role of SCEH in different metabolic pathways. Analyses of pyruvate dehydrogenase and respiratory chain complexes were performed in multiple tissues of two patients. RESULTS All patients were either homozygous or compound heterozygous for mutations in the ECHS1 gene, had markedly reduced SCEH enzymatic activity and protein level in fibroblasts. All patients presented with lactic acidosis. The first two patients presented with vacuolating leukoencephalopathy and basal ganglia abnormalities. The third patient showed a slow neurodegenerative condition with global brain atrophy and the fourth patient showed Leigh-like lesions with a single episode of metabolic acidosis. Clinical picture and metabolite analysis were not consistent with a mitochondrial fatty acid oxidation disorder, which was supported by the normal palmitate loading test in fibroblasts. Patient fibroblasts displayed deficient hydratase activity with different substrates tested. Pyruvate dehydrogenase activity was markedly reduced in particular in muscle from the most severely affected patients, which was caused by reduced expression of E2 protein, whereas E2 mRNA was increased. CONCLUSIONS Despite its activity towards substrates from different metabolic pathways, SCEH appears to be only crucial in valine metabolism, but not in isoleucine metabolism, and only of limited importance for mitochondrial fatty acid oxidation. In severely affected patients SCEH deficiency can cause a secondary pyruvate dehydrogenase deficiency contributing to the clinical presentation.
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Affiliation(s)
- Sacha Ferdinandusse
- Departments of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, AZ, 1105, The Netherlands.
| | - Marisa W Friederich
- Department of Pediatrics, Section of Genetics, University of Colorado, Aurora, CO, 80045, USA.
| | - Alberto Burlina
- Department of Paediatrics, Division of Metabolic Diseases, University Hospital of Padua, Padua, Italy.
| | - Jos P N Ruiter
- Departments of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, AZ, 1105, The Netherlands.
| | - Curtis R Coughlin
- Department of Pediatrics, Section of Genetics, University of Colorado, Aurora, CO, 80045, USA.
| | - Megan K Dishop
- Department of Pathology, University of Colorado, Aurora, CO, 80045, USA.
| | - Renata C Gallagher
- Department of Pediatrics, Section of Genetics, University of Colorado, Aurora, CO, 80045, USA.
| | - Jirair K Bedoyan
- Center for Inherited Disorders of Energy Metabolism (CIDEM), University Hospitals Case Medical Center, Cleveland, OH, 44106, USA. .,Departments of Genetics and Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA.
| | - Frédéric M Vaz
- Departments of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, AZ, 1105, The Netherlands.
| | - Hans R Waterham
- Departments of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, AZ, 1105, The Netherlands.
| | - Katherine Gowan
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, CO, 80045, USA.
| | - Kathryn Chatfield
- Department of Pediatrics, Section of Genetics, University of Colorado, Aurora, CO, 80045, USA. .,Department of Pediatrics, Section of Pediatric Cardiology, University of Colorado, Aurora, CO, 80045, USA.
| | - Kaitlyn Bloom
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, U74SA, USA.
| | - Michael J Bennett
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, U74SA, USA.
| | - Orly Elpeleg
- Monique and Jacques Roboh Department of Genetic Research, Hadassah, Hebrew University Medical Center, Jerusalem, Israel.
| | - Johan L K Van Hove
- Department of Pediatrics, Section of Genetics, University of Colorado, Aurora, CO, 80045, USA.
| | - Ronald J A Wanders
- Departments of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, AZ, 1105, The Netherlands.
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13
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Diekman EF, Ferdinandusse S, van der Pol L, Waterham HR, Ruiter JPN, Ijlst L, Wanders RJ, Houten SM, Wijburg FA, Blank AC, Asselbergs FW, Houtkooper RH, Visser G. Fatty acid oxidation flux predicts the clinical severity of VLCAD deficiency. Genet Med 2015; 17:989-94. [DOI: 10.1038/gim.2015.22] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 01/20/2015] [Indexed: 01/20/2023] Open
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14
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van Hasselt PM, Ferdinandusse S, Monroe GR, Ruiter JPN, Turkenburg M, Geerlings MJ, Duran K, Harakalova M, van der Zwaag B, Monavari AA, Okur I, Sharrard MJ, Cleary M, O'Connell N, Walker V, Rubio-Gozalbo ME, de Vries MC, Visser G, Houwen RHJ, van der Smagt JJ, Verhoeven-Duif NM, Wanders RJA, van Haaften G. Monocarboxylate transporter 1 deficiency and ketone utilization. N Engl J Med 2014; 371:1900-7. [PMID: 25390740 DOI: 10.1056/nejmoa1407778] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ketoacidosis is a potentially lethal condition caused by the imbalance between hepatic production and extrahepatic utilization of ketone bodies. We performed exome sequencing in a patient with recurrent, severe ketoacidosis and identified a homozygous frameshift mutation in the gene encoding monocarboxylate transporter 1 (SLC16A1, also called MCT1). Genetic analysis in 96 patients suspected of having ketolytic defects yielded seven additional inactivating mutations in MCT1, both homozygous and heterozygous. Mutational status was found to be correlated with ketoacidosis severity, MCT1 protein levels, and transport capacity. Thus, MCT1 deficiency is a novel cause of profound ketoacidosis; the present work suggests that MCT1-mediated ketone-body transport is needed to maintain acid-base balance.
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Affiliation(s)
- Peter M van Hasselt
- From the Division of Pediatrics, Department of Metabolic Diseases (P.M.H., G.V.), and the Division of Pediatrics, Department of Pediatric Gastroenterology (R.H.J.H.), Wilhelmina Children's Hospital, and the Center for Molecular Medicine, Department of Medical Genetics (G.R.M., M.J.G., K.D., M.H., B.Z., J.J.S., N.M.V.-D., G.H.), University Medical Center Utrecht, Utrecht, Laboratory Genetic Metabolic Diseases, Departments of Clinical Chemistry and Pediatrics, Academic Medical Center, Amsterdam (S.F., J.P.N.R., M.T., R.J.A.W.), the Division of Pediatrics, Department of Metabolic Diseases, and Laboratory Genetic Metabolic Diseases, Maastricht University Medical Center, Maastricht (M.E.R.-G.), and the Department of Pediatrics, Nijmegen Center for Mitochondrial Disorders, Radboud University Medical Center, Nijmegen (M.C.V.) - all in the Netherlands; the National Centre for Inherited Metabolic Disorders, Children's University Hospital, Dublin, Ireland (A.A.M.); the Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey (I.O.); and the Department of Paediatric Metabolic Medicine, Sheffield Children's Hospital, Sheffield (M.J.S.), the Department of Metabolic Medicine, Great Ormond Street Hospital NHS Foundation Trust, London (M.C.), Chemical Pathology, Department of Laboratory Medicine, Salisbury (N.O.), and the Department of Clinical Biochemistry, Southampton General Hospital, Southampton (V.W.) - all in the United Kingdom
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15
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van Weeghel M, Ofman R, Argmann CA, Ruiter JPN, Claessen N, Oussoren SV, Wanders RJA, Aten J, Houten SM. Identification and characterization of Eci3, a murine kidney-specific Δ3,Δ2-enoyl-CoA isomerase. FASEB J 2013; 28:1365-74. [PMID: 24344334 DOI: 10.1096/fj.13-240416] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Oxidation of unsaturated fatty acids requires the action of auxiliary enzymes, such as Δ(3),Δ(2)-enoyl-CoA isomerases. Here we describe a detailed biochemical, molecular, histological, and evolutionary characterization of Eci3, the fourth member of the mammalian enoyl-CoA isomerase family. Eci3 specifically evolved in rodents after gene duplication of Eci2. Eci3 is with 79% identity homologous to Eci2 and contains a peroxisomal targeting signal type 1. Subcellular fractionation of mouse kidney and immunofluorescence studies revealed a specific peroxisomal localization for Eci3. Expression studies showed that mouse Eci3 is almost exclusively expressed in kidney. By using immunohistochemistry, we found that Eci3 is not only expressed in cells of the proximal tubule, but also in a subset of cells in the tubulointerstitium and the glomerulus. In vitro, Eci3 catalyzed the isomerization of trans-3-nonenoyl-CoA to trans-2-nonenoyl-CoA equally efficient as Eci2, suggesting a role in oxidation of unsaturated fatty acids. However, in contrast to Eci2, in silico gene coexpression and enrichment analysis for Eci3 in kidney did not yield carboxylic acid metabolism, but diverse biological functions, such as ion transport (P=7.1E-3) and tissue morphogenesis (P=1.0E-3). Thus, Eci3 picked up a novel and unexpected role in kidney function during rodent evolution.
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Affiliation(s)
- Michel van Weeghel
- 1Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mt. Sinai, 1425 Madison Ave., Box 1498, New York, NY 10029, USA.
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16
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Houten SM, Herrema H, Te Brinke H, Denis S, Ruiter JPN, van Dijk TH, Argmann CA, Ottenhoff R, Müller M, Groen AK, Kuipers F, Reijngoud DJ, Wanders RJA. Impaired amino acid metabolism contributes to fasting-induced hypoglycemia in fatty acid oxidation defects. Hum Mol Genet 2013; 22:5249-61. [PMID: 23933733 DOI: 10.1093/hmg/ddt382] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The importance of mitochondrial fatty acid β-oxidation (FAO) as a glucose-sparing process is illustrated by patients with inherited defects in FAO, who may present with life-threatening fasting-induced hypoketotic hypoglycemia. It is unknown why peripheral glucose demand outpaces hepatic gluconeogenesis in these patients. In this study, we have systematically addressed the fasting response in long-chain acyl-CoA dehydrogenase-deficient (LCAD KO) mice. We demonstrate that the fasting-induced hypoglycemia in LCAD KO mice was initiated by an increased glucose requirement in peripheral tissues, leading to rapid hepatic glycogen depletion. Gluconeogenesis did not compensate for the increased glucose demand, which was not due to insufficient hepatic glucogenic capacity but rather caused by a shortage in the supply of glucogenic precursors. This shortage in supply was explained by a suppressed glucose-alanine cycle, decreased branched-chain amino acid metabolism and ultimately impaired protein mobilization. We conclude that during fasting, FAO not only serves to spare glucose but is also indispensable for amino acid metabolism, which is essential for the maintenance of adequate glucose production.
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Affiliation(s)
- Sander M Houten
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry
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17
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Dercksen M, Duran M, Ijlst L, Mienie LJ, Reinecke CJ, Ruiter JPN, Waterham HR, Wanders RJA. Clinical variability of isovaleric acidemia in a genetically homogeneous population. J Inherit Metab Dis 2012; 35:1021-9. [PMID: 22350545 DOI: 10.1007/s10545-012-9457-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 01/20/2012] [Accepted: 01/24/2012] [Indexed: 10/28/2022]
Abstract
Isovaleric acidemia (IVA) is one of the most common organic acidemias found in South Africa. Since 1983, a significant number of IVA cases have been identified in approximately 20,000 Caucasian patients screened for metabolic defects. IVA is caused by an autosomal recessive deficiency of isovaleryl-CoA dehydrogenase (IVD) resulting in the accumulation of isovaleryl-CoA and its metabolites. In total, 10 IVA patients and three carriers were available for phenotypic and genotypic investigation in this study. All patients were found to be homozygous for a single c.367 G > A (p.G123R) mutation. The amino acid substitution of a glycine to arginine resulted in a markedly reduced steady-state level of the IVD protein, which explains the nearly complete lack of IVD enzyme activity as assessed in fibroblast homogenates. Despite the genetic homogeneity of this South African IVA group, the clinical presentation varied widely, ranging from severe mental handicap and multiple episodes of metabolic derangement to an asymptomatic state. The variation may be due to poor dietary intervention, delayed diagnosis or even epigenetic and polygenetic factors of unknown origin.
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Affiliation(s)
- M Dercksen
- Centre for Human Metabonomics, North-West University (Potchefstroom Campus), Potchefstroom, South Africa.
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18
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Schmidt SP, Corydon TJ, Pedersen CB, Vang S, Palmfeldt J, Stenbroen V, Wanders RJA, Ruiter JPN, Gregersen N. Toxic response caused by a misfolding variant of the mitochondrial protein short-chain acyl-CoA dehydrogenase. J Inherit Metab Dis 2011; 34:465-75. [PMID: 21170680 PMCID: PMC3063561 DOI: 10.1007/s10545-010-9255-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Revised: 11/21/2010] [Accepted: 11/24/2010] [Indexed: 01/19/2023]
Abstract
BACKGROUND Variations in the gene ACADS, encoding the mitochondrial protein short-chain acyl CoA-dehydrogenase (SCAD), have been observed in individuals with clinical symptoms. The phenotype of SCAD deficiency (SCADD) is very heterogeneous, ranging from asymptomatic to severe, without a clear genotype-phenotype correlation, which suggests a multifactorial disorder. The pathophysiological relevance of the genetic variations in the SCAD gene is therefore disputed, and has not yet been elucidated, which is an important step in the investigation of SCADD etiology. AIM To determine whether the disease-associated misfolding variant of SCAD protein, p.Arg107Cys, disturbs mitochondrial function. METHODS We have developed a cell model system, stably expressing either the SCAD wild-type protein or the misfolding SCAD variant protein, p.Arg107Cys (c.319 C > T). The model system was used for investigation of SCAD with respect to expression, degree of misfolding, and enzymatic SCAD activity. Furthermore, cell proliferation and expression of selected stress response genes were investigated as well as proteomic analysis of mitochondria-enriched extracts in order to study the consequences of p.Arg107Cys protein expression using a global approach. CONCLUSIONS We found that expression of the p.Arg107Cys variant SCAD protein gives rise to inactive misfolded protein species, eliciting a mild toxic response manifested though a decreased proliferation rate and oxidative stress, as shown by an increased demand for the mitochondrial antioxidant SOD2. In addition, we found markers of apoptotic activity in the p.Arg107Cys expressing cells, which points to a possible pathophysiological role of this variant protein.
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Affiliation(s)
- Stinne P Schmidt
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Denmark.
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19
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Luís PBM, Ruiter JPN, Ijlst L, Tavares de Almeida I, Duran M, Mohsen AW, Vockley J, Wanders RJA, Silva MFB. Role of isovaleryl-CoA dehydrogenase and short branched-chain acyl-CoA dehydrogenase in the metabolism of valproic acid: implications for the branched-chain amino acid oxidation pathway. Drug Metab Dispos 2011; 39:1155-60. [PMID: 21430231 DOI: 10.1124/dmd.110.037606] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Many biological systems including the oxidative catabolic pathway for branched-chain amino acids (BCAAs) are affected in vivo by valproate therapy. In this study, we investigated the potential effect of valproic acid (VPA) and some of its metabolites on the metabolism of BCAAs. In vitro studies were performed using isovaleryl-CoA dehydrogenase (IVD), isobutyryl-CoA dehydrogenase (IBD), and short branched-chain acyl-CoA dehydrogenase (SBCAD), enzymes involved in the degradation pathway of leucine, valine, and isoleucine. The enzymatic activities of the three purified human enzymes were measured using optimized high-performance liquid chromatography procedures, and the respective kinetic parameters were determined in the absence and presence of VPA and the corresponding CoA and dephosphoCoA conjugates. Valproyl-CoA and valproyl-dephosphoCoA inhibited IVD activity significantly by a purely competitive mechanism with K(i) values of 74 ± 4 and 170 ± 12 μM, respectively. IBD activity was not affected by any of the tested VPA esters. However, valproyl-CoA did inhibit SBCAD activity by a purely competitive mechanism with a K(i) of 249 ± 29 μM. In addition, valproyl-dephosphoCoA inhibited SBCAD activity via a distinct mechanism (K(i) = 511 ± 96 μM) that appeared to be of the mixed type. Furthermore, we show that both SBCAD and IVD are active, using valproyl-CoA as a substrate. The catalytic efficiency of SBCAD turned out to be much higher than that of IVD, demonstrating that SBCAD is the most probable candidate for the first dehydrogenation step of VPA β-oxidation. Our data explain some of the effects of valproate on the branched-chain amino acid metabolism and shed new light on the biotransformation pathway of valproate.
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Affiliation(s)
- Paula B M Luís
- Research Institute for Medicines and Pharmaceutical Sciences-iMED.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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20
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Avis HJ, Hargreaves IP, Ruiter JPN, Land JM, Wanders RJ, Wijburg FA. Rosuvastatin lowers coenzyme Q10 levels, but not mitochondrial adenosine triphosphate synthesis, in children with familial hypercholesterolemia. J Pediatr 2011; 158:458-62. [PMID: 20884007 DOI: 10.1016/j.jpeds.2010.08.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 08/04/2010] [Accepted: 08/13/2010] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To investigate whether statin therapy affects coenzyme Q10 (CoQ10) status in children with heterozygous familial hypercholesterolemia (FH). STUDY DESIGN Samples were obtained at baseline (treatment naïve) and after dose titration with rosuvastatin, aiming for a low-density lipoprotein cholesterol level of 110 mg/dL. Twenty-nine patients were treated with 5, 10, or 20 mg of rosuvastatin for a mean period of 29 weeks. RESULTS We found a significant (32%) decrease in peripheral blood mononuclear cell (PBMC) CoQ10 level (P = .02), but no change in PBMC adenosine triphosphate synthesis (P = .60). Uncorrected plasma CoQ10 values were decreased significantly, by 45% (P < .01). In contrast, ratios of plasma CoQ10/total cholesterol and CoQ10/low-density lipoprotein cholesterol remained equal during treatment. CONCLUSIONS In children with FH, rosuvastatin causes a significant decrease in cellular PBMC CoQ10 status but does not affect mitochondrial adenosine triphosphate synthesis in children with FH. Further studies should address whether (rare) side effects of statin therapy could be explained by a deterioration in CoQ10 status.
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Affiliation(s)
- Hans J Avis
- Department of Pediatrics, Academic Medical Center, Amsterdam, The Netherlands
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21
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Wanders RJA, Ruiter JPN, IJLst L, Waterham HR, Houten SM. The enzymology of mitochondrial fatty acid beta-oxidation and its application to follow-up analysis of positive neonatal screening results. J Inherit Metab Dis 2010; 33:479-94. [PMID: 20490924 PMCID: PMC2946543 DOI: 10.1007/s10545-010-9104-8] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 03/19/2010] [Accepted: 04/12/2010] [Indexed: 12/22/2022]
Abstract
Oxidation of fatty acids in mitochondria is a key physiological process in higher eukaryotes including humans. The importance of the mitochondrial beta-oxidation system in humans is exemplified by the existence of a group of genetic diseases in man caused by an impairment in the mitochondrial oxidation of fatty acids. Identification of patients with a defect in mitochondrial beta-oxidation has long remained notoriously difficult, but the introduction of tandem-mass spectrometry in laboratories for genetic metabolic diseases has revolutionalized the field by allowing the rapid and sensitive analysis of acylcarnitines. Equally important is that much progress has been made with respect to the development of specific enzyme assays to identify the enzyme defect in patients subsequently followed by genetic analysis. In this review, we will describe the current state of knowledge in the field of fatty acid oxidation enzymology and its application to the follow-up analysis of positive neonatal screening results.
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Affiliation(s)
- Ronald J A Wanders
- Department of Clinical Chemistry, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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22
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Pedersen CB, Zolkipli Z, Vang S, Palmfeldt J, Kjeldsen M, Stenbroen V, Schmidt SP, Wanders RJA, Ruiter JPN, Wibrand F, Tein I, Gregersen N. Antioxidant dysfunction: potential risk for neurotoxicity in ethylmalonic aciduria. J Inherit Metab Dis 2010; 33:211-22. [PMID: 20443061 DOI: 10.1007/s10545-010-9086-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 03/08/2010] [Accepted: 03/10/2010] [Indexed: 11/29/2022]
Abstract
Mitochondrial dysfunction and oxidative stress are central to the molecular basis of several human diseases associated with neuromuscular disabilities. We hypothesize that mitochondrial dysfunction also contributes to the neuromuscular symptoms observed in patients with ethylmalonic aciduria and homozygosity for ACADS c.625G>A-a common variant of the short-chain acyl-coenzyme A (CoA) dehydrogenase (SCAD) enzyme in the mitochondrial fatty acid oxidation pathway. This study sought to identify the specific factors that initiate cell dysfunction in these patients. We investigated fibroblast cultures from 10 patients with neuromuscular disabilities, elevated levels of ethylmalonic acid (EMA) (>50 mmol/mol creatinine), and ACADS c.625G>A homozygosity. Functional analyses, i.e., ACADS gene and protein expression as well as SCAD enzyme activity measurements, were performed together with a global nano liquid chromatography tandem mass spectroscopy (nano-LC-MS/MS)-based screening of the mitochondrial proteome in patient fibroblasts. Moreover, cell viability of patient fibroblasts exposed to menadione-induced oxidative stress was evaluated. Loss of SCAD function was detected in the patient group, most likely due to decreased ACADS gene expression and/or elimination of misfolded SCAD protein. Analysis of the mitochondrial proteome in patient fibroblasts identified a number of differentially expressed protein candidates, including reduced expression of the antioxidant superoxide dismutase 2 (SOD2). Additionally, patient fibroblasts demonstrated significantly higher sensitivity to oxidative stress than control fibroblasts. We propose that reduced mitochondrial antioxidant capacity is a potential risk factor for ACADS c.625G>A-associated ethylmalonic aciduria and that mitochondrial dysfunction contributes to the neurotoxicity observed in patients.
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Affiliation(s)
- Christina B Pedersen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, Aarhus N, Denmark.
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23
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Chegary M, Brinke HT, Ruiter JPN, Wijburg FA, Stoll MSK, Minkler PE, van Weeghel M, Schulz H, Hoppel CL, Wanders RJA, Houten SM. Mitochondrial long chain fatty acid beta-oxidation in man and mouse. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:806-15. [PMID: 19465148 DOI: 10.1016/j.bbalip.2009.05.006] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 04/28/2009] [Accepted: 05/18/2009] [Indexed: 10/20/2022]
Abstract
Several mouse models for mitochondrial fatty acid beta-oxidation (FAO) defects have been developed. So far, these models have contributed little to our current understanding of the pathophysiology. The objective of this study was to explore differences between murine and human FAO. Using a combination of analytical, biochemical and molecular methods, we compared fibroblasts of long chain acyl-CoA dehydrogenase knockout (LCAD(-/-)), very long chain acyl-CoA dehydrogenase knockout (VLCAD(-/-)) and wild type mice with fibroblasts of VLCAD-deficient patients and human controls. We show that in mice, LCAD and VLCAD have overlapping and distinct roles in FAO. The absence of VLCAD is apparently fully compensated, whereas LCAD deficiency is not. LCAD plays an essential role in the oxidation of unsaturated fatty acids such as oleic acid, but seems redundant in the oxidation of saturated fatty acids. In strong contrast, LCAD is neither detectable at the mRNA level nor at the protein level in men, making VLCAD indispensable in FAO. Our findings open new avenues to employ the existing mouse models to study the pathophysiology of human FAO defects.
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Affiliation(s)
- Malika Chegary
- Department of Clinical Chemistry, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, The Netherlands
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24
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Illsinger S, Lücke T, Peter M, Ruiter JPN, Wanders RJA, Deschauer M, Handig I, Wuyts W, Das AM. Carnitine-palmitoyltransferase 2 deficiency: novel mutations and relevance of newborn screening. Am J Med Genet A 2008; 146A:2925-8. [PMID: 18925671 DOI: 10.1002/ajmg.a.32545] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We report on a newborn male, born at term after an uneventful pregnancy presenting with a pathological acylcarnitine profile in routine newborn screening on the third day of life. The profile showed characteristic elevations of C14:0-, C16:0-, C16:1- and C18:1-acylcarnitines, while the ratio of (C16 + C18:1)/C2 was increased, suggesting CPT2- or carnitine-acylcarnitine-translocase- deficiency. The acylcarnitine profile in blood taken on day 9 was normal with breast milk feeding. No dicarboxylic aciduria was found. In fibroblasts, the activity of CPT2 was decreased to 25%, overall oxidation of the long-chain fatty acids was reduced to 10% of control values. Sequence analysis of the CPT2 gene showed heterozygosity for two previously undescribed mutations in exon 4: c.748-749delAA (truncating), and c.1436A > G (p.Tyr479Cys; missense) mutations. The asymptomatic parents were found to be heterozygous, the mother carries the c.748-749delAA and the father the c.1436A > G mutation. The boy is now 2.5 years old; no clinical symptoms associated with the marked impairment of long-chain fatty acid oxidation have occurred. Confirmation of mitochondrial fatty acid oxidation defects from an initial abnormal newborn-screening by tandem mass spectrometry should include enzyme and, if possible, molecular genetic analysis despite a normal 2nd screening. Biochemical testing of urine (organic acids) may be unrevealing.
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Affiliation(s)
- Sabine Illsinger
- Department of Pediatric Kidney-, Liver- and Metabolic Diseases, Children's Hospital Hannover Medical School, Hannover, Germany.
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25
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Westermann CM, Dorland L, Votion DM, de Sain-van der Velden MGM, Wijnberg ID, Wanders RJA, Spliet WGM, Testerink N, Berger R, Ruiter JPN, van der Kolk JH. Acquired multiple Acyl-CoA dehydrogenase deficiency in 10 horses with atypical myopathy. Neuromuscul Disord 2008; 18:355-64. [PMID: 18406615 DOI: 10.1016/j.nmd.2008.02.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 02/07/2008] [Accepted: 02/18/2008] [Indexed: 11/29/2022]
Abstract
The aim of the current study was to assess lipid metabolism in horses with atypical myopathy. Urine samples from 10 cases were subjected to analysis of organic acids, glycine conjugates, and acylcarnitines revealing increased mean excretion of lactic acid, ethylmalonic acid, 2-methylsuccinic acid, butyrylglycine, (iso)valerylglycine, hexanoylglycine, free carnitine, C2-, C3-, C4-, C5-, C6-, C8-, C8:1-, C10:1-, and C10:2-carnitine as compared with 15 control horses (12 healthy and three with acute myopathy due to other causes). Analysis of plasma revealed similar results for these predominantly short-chain acylcarnitines. Furthermore, measurement of dehydrogenase activities in lateral vastus muscle from one horse with atypical myopathy indeed showed deficiencies of short-chain acyl-CoA dehydrogenase (0.66 as compared with 2.27 and 2.48 in two controls), medium-chain acyl-CoA dehydrogenase (0.36 as compared with 4.31 and 4.82 in two controls) and isovaleryl-CoA dehydrogenase (0.74 as compared with 1.43 and 1.61 nmol min(-1) mg(-1) in two controls). A deficiency of several mitochondrial dehydrogenases that utilize flavin adenine dinucleotide as cofactor including the acyl-CoA dehydrogenases of fatty acid beta-oxidation, and enzymes that degrade the CoA-esters of glutaric acid, isovaleric acid, 2-methylbutyric acid, isobutyric acid, and sarcosine was suspected in 10 out of 10 cases as the possible etiology for a highly fatal and prevalent toxic equine muscle disease similar to the combined metabolic derangements seen in human multiple acyl-CoA dehydrogenase deficiency also known as glutaric acidemia type II.
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Affiliation(s)
- C M Westermann
- Department of Equine Sciences, Medicine Section, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 114, 3508 TD Utrecht, The Netherlands
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26
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Silva MFB, Aires CCP, Luis PBM, Ruiter JPN, IJlst L, Duran M, Wanders RJA, Tavares de Almeida I. Valproic acid metabolism and its effects on mitochondrial fatty acid oxidation: a review. J Inherit Metab Dis 2008; 31:205-16. [PMID: 18392741 DOI: 10.1007/s10545-008-0841-x] [Citation(s) in RCA: 253] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Revised: 02/12/2008] [Accepted: 02/15/2008] [Indexed: 12/25/2022]
Abstract
Valproic acid (VPA; 2-n-propylpentanoic acid) is widely used as a major drug in the treatment of epilepsy and in the control of several types of seizures. Being a simple fatty acid, VPA is a substrate for the fatty acid beta-oxidation (FAO) pathway, which takes place primarily in mitochondria. The toxicity of valproate has long been considered to be due primarily to its interference with mitochondrial beta-oxidation. The metabolism of the drug, its effects on enzymes of FAO and their cofactors such as CoA and/or carnitine will be reviewed. The cumulative consequences of VPA therapy in inborn errors of metabolism (IEMs) and the importance of recognizing an underlying IEM in cases of VPA-induced steatosis and acute liver toxicity are two different concepts that will be emphasized.
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Affiliation(s)
- M F B Silva
- Centro de Patogénese Molecular-UBMBE, iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Lisboa, Portugal.
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27
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Gobin-Limballe S, Djouadi F, Aubey F, Olpin S, Andresen BS, Yamaguchi S, Mandel H, Fukao T, Ruiter JPN, Wanders RJA, McAndrew R, Kim JJ, Bastin J. Genetic basis for correction of very-long-chain acyl-coenzyme A dehydrogenase deficiency by bezafibrate in patient fibroblasts: toward a genotype-based therapy. Am J Hum Genet 2007; 81:1133-43. [PMID: 17999356 DOI: 10.1086/522375] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Accepted: 08/01/2007] [Indexed: 12/30/2022] Open
Abstract
Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is an inborn mitochondrial fatty-acid beta-oxidation (FAO) defect associated with a broad mutational spectrum, with phenotypes ranging from fatal cardiopathy in infancy to adolescent-onset myopathy, and for which there is no established treatment. Recent data suggest that bezafibrate could improve the FAO capacities in beta-oxidation-deficient cells, by enhancing the residual level of mutant enzyme activity via gene-expression stimulation. Since VLCAD-deficient patients frequently harbor missense mutations with unpredictable effects on enzyme activity, we investigated the response to bezafibrate as a function of genotype in 33 VLCAD-deficient fibroblasts representing 45 different mutations. Treatment with bezafibrate (400 microM for 48 h) resulted in a marked increase in FAO capacities, often leading to restoration of normal values, for 21 genotypes that mainly corresponded to patients with the myopathic phenotype. In contrast, bezafibrate induced no changes in FAO for 11 genotypes corresponding to severe neonatal or infantile phenotypes. This pattern of response was not due to differential inductions of VLCAD messenger RNA, as shown by quantitative real-time polymerase chain reaction, but reflected variable increases in measured VLCAD residual enzyme activity in response to bezafibrate. Genotype cross-analysis allowed the identification of alleles carrying missense mutations, which could account for these different pharmacological profiles and, on this basis, led to the characterization of 9 mild and 11 severe missense mutations. Altogether, the responses to bezafibrate reflected the severity of the metabolic blockage in various genotypes, which appeared to be correlated with the phenotype, thus providing a new approach for analysis of genetic heterogeneity. Finally, this study emphasizes the potential of bezafibrate, a widely prescribed hypolipidemic drug, for the correction of VLCAD deficiency and exemplifies the integration of molecular information in a therapeutic strategy.
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Affiliation(s)
- S Gobin-Limballe
- Université Paris-Descartes, Centre National de la Recherche Scientifique Biotram, Paris, France
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28
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Luís PBM, Ruiter JPN, Aires CCP, Soveral G, de Almeida IT, Duran M, Wanders RJA, Silva MFB. Valproic acid metabolites inhibit dihydrolipoyl dehydrogenase activity leading to impaired 2-oxoglutarate-driven oxidative phosphorylation. Biochim Biophys Acta 2007; 1767:1126-33. [PMID: 17706936 DOI: 10.1016/j.bbabio.2007.06.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 06/21/2007] [Accepted: 06/26/2007] [Indexed: 11/26/2022]
Abstract
The effect of the antiepileptic drug valproic acid (VPA) on mitochondrial oxidative phosphorylation (OXPHOS) was investigated in vitro. Two experimental approaches were used, in the presence of selected respiratory-chain substrates: (1) formation of ATP in digitonin permeabilized rat hepatocytes and (2) measurement of the rate of oxygen consumption by polarography in rat liver mitochondria. VPA (0.1-1.0 mM) was found to inhibit oxygen consumption and ATP synthesis under state 3 conditions with glutamate and 2-oxoglutarate as respiratory substrates. No inhibitory effect on OXPHOS was observed when succinate (plus rotenone) was used as substrate. We tested the hypothesis that dihydrolipoyl dehydrogenase (DLDH) might be a direct target of VPA, especially its acyl-CoA intermediates. Valproyl-CoA (0.5-1.0 mM) and valproyl-dephosphoCoA (0.5-1.0 mM) both inhibited the DLDH activity, acting apparently by different mechanisms. The decreased activity of DLDH induced by VPA metabolites may, at least in part, account for the impaired rate of oxygen consumption and ATP synthesis in mitochondria if 2-oxoglutarate or glutamate were used as respiratory substrates, thus limiting the flux of these substrates through the citric acid cycle.
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Affiliation(s)
- Paula B M Luís
- Centro de Patogénese Molecular, Unidade de Biologia Molecular e Biopatologia Experimental, (UBMBE) Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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29
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Aires CCP, Ruiter JPN, Luís PBM, ten Brink HJ, Ijlst L, de Almeida IT, Duran M, Wanders RJA, Silva MFB. Studies on the extra-mitochondrial CoA-ester formation of valproic and Δ4-valproic acids. Biochim Biophys Acta Mol Cell Biol Lipids 2007; 1771:533-43. [PMID: 17321204 DOI: 10.1016/j.bbalip.2007.01.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 01/15/2007] [Accepted: 01/17/2007] [Indexed: 10/23/2022]
Abstract
The hypothesis whether valproic acid (VPA) and its main microsomal metabolite, Delta(4)-valproic acid, can be activated to the respective CoA esters in the cell cytosol was investigated. The valproyl-CoA formation was measured in different subcellular fractions obtained by differential centrifugation of liver homogenates of rats treated with VPA (studies ex vivo) and digitonin fractionation of rat hepatocytes incubated with VPA and cofactors (studies in vitro). The results show that VPA activation may occur in the cytosol and is not restricted to the mitochondrial matrix as believed until now. Furthermore, the activation of Delta(4)-VPA is demonstrated in vitro. Valproyl-CoA and Delta(4)-valproyl-CoA were detected after in vitro incubations and the former also in the mitochondrial and cytosolic fractions obtained from liver cells of treated rats. The activation to valproyl-CoA was characterized in cytosolic fractions, optimized with respect to time and protein and the kinetic constants (K(m)(app)) were estimated for the reaction substrates. Other medium-chain fatty acids decreased the formation of valproyl-CoA suggesting a competition for both mitochondrial and extra-mitochondrial VPA activating enzymes. The present findings suggest additional mechanisms of mitochondrial dysfunction associated with VPA, and they may contribute to the further understanding of the toxic effects associated with this drug.
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Affiliation(s)
- Cátia C P Aires
- UBMBE, Centro de Patogénese Molecular, Faculdade de Farmácia da Universidade de Lisboa, Av Prof Gama Pinto, Lisboa, Portugal
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30
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Yamada K, Fukao T, Zhang G, Sakurai S, Ruiter JPN, Wanders RJA, Kondo N. Single-base substitution at the last nucleotide of exon 6 (c.671G>A), resulting in the skipping of exon 6, and exons 6 and 7 in human succinyl-CoA:3-ketoacid CoA transferase (SCOT) gene. Mol Genet Metab 2007; 90:291-7. [PMID: 17169596 DOI: 10.1016/j.ymgme.2006.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Revised: 10/27/2006] [Accepted: 10/28/2006] [Indexed: 10/23/2022]
Abstract
Succinyl-CoA:3-ketoacid CoA transferase (SCOT, EC 2.8.3.5) is the key enzyme for ketone body utilization. Hereditary SCOT deficiency (MIM 245050) causes episodes of severe ketoacidosis. We identified a homozygous point mutation (c.671G>A) , which is a single-base substitution at the last nucleotide of exon 6, in a Turkish patient (GS12) with SCOT deficiency. This point mutation resulted in the skipping of exon 6, and exons 6 and 7 in human SCOT genes. To understand why the c.671G>A causes exons 6 and 7 skipping, nuclear RNA was separated from cytoplasmic RNA and both were analyzed by RT-PCR. In nuclear RNA, SCOT mRNA with exon 6 skipping was predominant and mRNA with exons 6 and 7 skipping was hardly detected, whereas the latter became one of major mRNA species in cytoplasmic RNA. This discrepancy was interpreted as follows: exon 6 skipping causes a frameshift and nonsense-mediated RNA decay in the cytosol, so mRNA with exon 6 skipping was unstable. On the other hand, SCOT mRNA with exons 6 and 7 is a minor transcript but it retains the reading-frame and is stable in cytosol. As a result, the latter mRNA is more abundant under steady-state conditions as compared to the former mRNA.
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Affiliation(s)
- Keitaro Yamada
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, Gifu 501-1194, Japan
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31
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van Vlies N, Ruiter JPN, Doolaard M, Wanders RJA, Vaz FM. An improved enzyme assay for carnitine palmitoyl transferase I in fibroblasts using tandem mass spectrometry. Mol Genet Metab 2007; 90:24-9. [PMID: 16935015 DOI: 10.1016/j.ymgme.2006.07.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 07/19/2006] [Accepted: 07/19/2006] [Indexed: 10/24/2022]
Abstract
Carnitine palmitoyl transferase I (CPTI), which converts acyl-CoA and carnitine into acyl-carnitine and free CoASH, is the rate limiting enzyme of hepatic mitochondrial beta-oxidation. CPTI-deficiency is a severe disorder characterized by Reye-like attacks with hypoketotic hypoglycemia, hepatomegaly, elevated liver enzymes and hyperammonemia. We developed a simple tandem-MS-based assay to measure CPTI activity in human fibroblasts. Surprisingly, a large part of the palmitoyl-carnitine formed in our assay by CPTI was degraded into C14- to C2-acyl-carnitines. Degradation of the product of CPTI leads to under estimation of the CPTI activity. When we used potassium cyanide to inhibit enzymes downstream of CPTI and thereby degradation of the product, we measured four times more CPTI activity than the previous methods. This inhibition is essential for correct calculation of CPTI activity. In fibroblasts of CPTI-deficient patients, CPTI activity was not detectable and this assay can be used for the diagnosis of CPTI-deficiency.
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Affiliation(s)
- Naomi van Vlies
- Department of Clinical Chemistry and Pediatrics, Laboratory Genetic Metabolic Diseases (F0-224), Academic Medical Center, University of Amsterdam, PO Box 22700, 1100 DE Amsterdam, The Netherlands
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32
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Loupatty FJ, Clayton PT, Ruiter JPN, Ofman R, Ijlst L, Brown GK, Thorburn DR, Harris RA, Duran M, Desousa C, Krywawych S, Heales SJR, Wanders RJA. Mutations in the gene encoding 3-hydroxyisobutyryl-CoA hydrolase results in progressive infantile neurodegeneration. Am J Hum Genet 2007; 80:195-9. [PMID: 17160907 PMCID: PMC1785315 DOI: 10.1086/510725] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Accepted: 10/31/2006] [Indexed: 11/03/2022] Open
Abstract
Only a single patient with 3-hydroxyisobutyryl-CoA hydrolase deficiency has been described in the literature, and the molecular basis of this inborn error of valine catabolism has remained unknown until now. Here, we present a second patient with 3-hydroxyisobutyryl-CoA hydrolase deficiency, who was identified through blood spot acylcarnitine analysis showing persistently increased levels of hydroxy-C(4)-carnitine. Both patients manifested hypotonia, poor feeding, motor delay, and subsequent neurological regression in infancy. Additional features in the newly identified patient included episodes of ketoacidosis and Leigh-like changes in the basal ganglia on a magnetic resonance imaging scan. In cultured skin fibroblasts from both patients, the 3-hydroxyisobutyryl-CoA hydrolase activity was deficient, and virtually no 3-hydroxyisobutyryl-CoA hydrolase protein could be detected by western blotting. Molecular analysis in both patients uncovered mutations in the HIBCH gene, including one missense mutation in a conserved part of the protein and two mutations affecting splicing. A carefully interpreted acylcarnitine profile will allow more patients with 3-hydroxyisobutyryl-CoA hydrolase deficiency to be diagnosed.
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Affiliation(s)
- Ference J Loupatty
- Department of Clinical Chemistry and Pediatrics, Emma Children's Hospital, Amsterdam, The Netherlands
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33
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Gloerich J, van den Brink DM, Ruiter JPN, van Vlies N, Vaz FM, Wanders RJA, Ferdinandusse S. Metabolism of phytol to phytanic acid in the mouse, and the role of PPARα in its regulation. J Lipid Res 2007; 48:77-85. [PMID: 17015885 DOI: 10.1194/jlr.m600050-jlr200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phytol, a branched-chain fatty alcohol, is the naturally occurring precursor of phytanic and pristanic acid, branched-chain fatty acids that are both ligands for the nuclear hormone receptor peroxisome proliferator-activated receptor alpha (PPARalpha). To investigate the metabolism of phytol and the role of PPARalpha in its regulation, wild-type and PPARalpha knockout (PPARalpha-/-) mice were fed a phytol-enriched diet or, for comparison, a diet enriched with Wy-14,643, a synthetic PPARalpha agonist. After the phytol-enriched diet, phytol could only be detected in small intestine, the site of uptake, and liver. Upon longer duration of the diet, the level of the (E)-isomer of phytol increased significantly in the liver of PPARalpha-/- mice compared with wild-type mice. Activity measurements of the enzymes involved in phytol metabolism showed that treatment with a PPARalpha agonist resulted in a PPARalpha-dependent induction of at least two steps of the phytol degradation pathway in liver. Furthermore, the enzymes involved showed a higher activity toward the (E)-isomer than the (Z)-isomer of their respective substrates, indicating a stereospecificity toward the metabolism of (E)-phytol. In conclusion, the results described here show that the conversion of phytol to phytanic acid is regulated via PPARalpha and is specific for the breakdown of (E)-phytol.
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Affiliation(s)
- J Gloerich
- Laboratory of Genetic Metabolic Diseases, Department of Clinical Chemistry, Emma's Children's Hospital, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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34
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Pedersen CB, Bischoff C, Christensen E, Simonsen H, Lund AM, Young SP, Koeberl DD, Millington DS, Roe CR, Roe DS, Wanders RJA, Ruiter JPN, Keppen LD, Stein Q, Knudsen I, Gregersen N, Andresen BS. Variations in IBD (ACAD8) in children with elevated C4-carnitine detected by tandem mass spectrometry newborn screening. Pediatr Res 2006; 60:315-20. [PMID: 16857760 DOI: 10.1203/01.pdr.0000233085.72522.04] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The isobutyryl-CoA dehydrogenase (IBD) enzyme is involved in the degradation of valine. IBD deficiency was first reported in 1998 and subsequent genetic investigations identified acyl-CoA dehydrogenase (ACAD) 8, now IBD, as the gene responsible for IBD deficiency. Only three individuals homozygous or compound heterozygous for variations in the IBD gene have been reported. We present IBD deficiency in an additional four newborns with elevated C(4)-carnitine identified by tandem mass spectrometry (MS/MS) screening in Denmark and the United States. Three showed urinary excretions of isobutyryl-glycine, and in vitro probe analysis of fibroblasts from two newborns indicated enzymatic IBD defect. Molecular genetic analysis revealed seven new rare variations in the IBD gene (c.348C>A, c.400G>T, c.409G>A, c.455T>C, c.958G>A, c.1000C>T and c.1154G>A). Furthermore, sequence analysis of the short-chain acyl-CoA dehydrogenase (SCAD) gene revealed heterozygosity for the prevalent c.625G>A susceptibility variation in all newborns and in the first reported IBD patient. Functional studies in isolated mitochondria demonstrated that the IBD variations present in the Danish newborn (c.409G>A and c.958G>A) together with a previously published IBD variation (c.905G>A) disturbed protein folding and reduced the levels of correctly folded IBD tetramers. Accordingly, low/no IBD residual enzyme activity was detectable when the variant IBD proteins were overexpressed in Chang cells.
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Affiliation(s)
- Christina B Pedersen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby Sygehus, 8200 Aarhus N, Denmark
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35
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Oey NA, Ruiter JPN, Ijlst L, Attie-Bitach T, Vekemans M, Wanders RJA, Wijburg FA. Acyl-CoA dehydrogenase 9 (ACAD 9) is the long-chain acyl-CoA dehydrogenase in human embryonic and fetal brain. Biochem Biophys Res Commun 2006; 346:33-7. [PMID: 16750164 DOI: 10.1016/j.bbrc.2006.05.088] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Accepted: 05/08/2006] [Indexed: 11/20/2022]
Abstract
We recently reported the expression and activity of several fatty acid oxidation enzymes in human embryonic and fetal tissues including brain and spinal cord. Liver and heart showed expression of both very long-chain acyl-CoA dehydrogenase (VLCAD) and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) mRNA. However, while mRNA expression of LCHAD could be clearly detected in the retina and spinal cord, expression of VLCAD mRNA was low to undetectable in these tissues. Nevertheless, abundant acyl-CoA dehydrogenase (ACAD) activity was detected with palmitoyl-CoA as substrate in fetal central nervous tissue. These conflicting data suggested the presence of a different long-chain ACAD in human embryonic and fetal brain. In this study, using in situ hybridization as well as enzymatic studies, we identified acyl-CoA dehydrogenase 9 (ACAD 9) as the long-chain ACAD in human embryonic and fetal central nervous tissue. Until now, no clinical signs and symptoms of central nervous system involvement have been reported in VLCAD deficiency. A novel long-chain FAO defect, i.e., ACAD 9 deficiency with only central nervous system involvement, could, if not lethal during intra uterine development, easily escape proper diagnosis, since probably no classical signs and symptoms of FAO deficiency will be observed. Screening for ACAD 9 deficiency in patients with undefined neurological symptoms and/or impairment in neurological development of unknown origin is necessary to establish if ACAD 9 deficiency exists as a separate disease entity.
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Affiliation(s)
- N A Oey
- Department of Paediatrics, Laboratory for Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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36
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Timmermans EC, Tebas P, Ruiter JPN, Wanders RJA, de Ronde A, de Baar MP. Real-Time Nucleic Acid Sequence–Based Amplification Assay to Quantify Changes in Mitochondrial DNA Concentrations in Cell Cultures and Blood Cells from HIV-Infected Patients Receiving Antiviral Therapy. Clin Chem 2006; 52:979-87. [PMID: 16601068 DOI: 10.1373/clinchem.2005.062901] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
Background: To study the clinical relevance of changes in mitochondrial DNA (mtDNA) in peripheral blood mononuclear cells (PBMCs) attributable to HIV infection and/or combination antiretroviral therapy (cART), a high-throughput molecular assay to quantify mtDNA is required.
Methods: We developed a quantitative real-time duplex nucleic acid sequence–based amplification assay in which both mtDNA and nuclear DNA are simultaneously amplified in 1 tube. The assay could accurately quantify mtDNA in a range of 15–1500 copies of mtDNA per 2 genomic copies with an intrarun variation of 11% and an interrun variation of 16%. We compared this real-time assay with the lactate/pyruvate ratios in fibroblasts incubated with glucose and exposed to zalcitabine. Additionally, we studied the effects of platelet contamination and the in vivo effects of cART on mtDNA in PBMCs from a small group of patients.
Results: Decreases in mtDNA preceded the increase in lactate/pyruvate ratios and vice versa when zalcitabine was eliminated from the culture. Platelets affected the mtDNA in PBMCs if >5 platelets per PBMC were present. Within 12 weeks, mtDNA increased and remained increased in PBMCs from patients on continuous treatment with zidovudine/lamivudine/indinavir therapy (P = 0.03), but increased if patients were switched to stavudine/didanosine therapy (P = 0.008).
Conclusion: After drug exposure, the mtDNA assay can detect changes in mtDNA concentrations in cell lines and PBMCs, when properly controlled for platelet effects, earlier than traditional assays.
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37
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Liebig M, Gyenes M, Brauers G, Ruiter JPN, Wendel U, Mayatepek E, Strauss AW, Wanders RJA, Spiekerkoetter U. Carnitine supplementation induces long-chain acylcarnitine production--studies in the VLCAD-deficient mouse. J Inherit Metab Dis 2006; 29:343-4. [PMID: 16763898 DOI: 10.1007/s10545-006-0249-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2005] [Accepted: 02/03/2006] [Indexed: 10/24/2022]
Abstract
Carnitine supplementation does not affect carnitine concentrations in tissues of wild-type and very long-chain acyl-CoA dehydrogenase-deficient mice, but results in an increase in long-chain acylcarnitine production.
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Affiliation(s)
- M Liebig
- Department of General Pediatrics, University Children's Hospital, Duesseldorf, Germany
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38
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Gloerich J, Ruiter JPN, van den Brink DM, Ofman R, Ferdinandusse S, Wanders RJA. Peroxisomal trans-2-enoyl-CoA reductase is involved in phytol degradation. FEBS Lett 2006; 580:2092-6. [PMID: 16546181 DOI: 10.1016/j.febslet.2006.03.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2006] [Accepted: 03/04/2006] [Indexed: 11/23/2022]
Abstract
Phytol is a naturally occurring precursor of phytanic acid. The last step in the conversion of phytol to phytanoyl-CoA is the reduction of phytenoyl-CoA mediated by an, as yet, unidentified enzyme. A candidate for this reaction is a previously described peroxisomal trans-2-enoyl-CoA reductase (TER). To investigate this, human TER was expressed in E. coli as an MBP-fusion protein. The purified recombinant protein was shown to have high reductase activity towards trans-phytenoyl-CoA, but not towards the peroxisomal beta-oxidation intermediates C24:1-CoA and pristenoyl-CoA. In conclusion, our results show that human TER is responsible for the reduction of phytenoyl-CoA to phytanoyl-CoA in peroxisomes.
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Affiliation(s)
- J Gloerich
- Laboratory Genetic Metabolic Diseases (F0-224), Department of Clinical Chemistry, Emma's Children's Hospital, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
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39
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Loupatty FJ, van der Steen A, Ijlst L, Ruiter JPN, Ofman R, Baumgartner MR, Ballhausen D, Yamaguchi S, Duran M, Wanders RJA. Clinical, biochemical, and molecular findings in three patients with 3-hydroxyisobutyric aciduria. Mol Genet Metab 2006; 87:243-8. [PMID: 16466957 DOI: 10.1016/j.ymgme.2005.09.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 09/22/2005] [Accepted: 09/22/2005] [Indexed: 11/17/2022]
Abstract
3-Hydroxyisobutyric aciduria is a rare entity and affected individuals display a range of clinical manifestations including dysmorphic features and neurodevelopmental problems in the majority of patients. Here, we present two novel patients with 3-hydroxyisobutyric aciduria. To our knowledge, these are the 11th and 12th cases of 3-hydroxyisobutyic aciduria reported. It is believed that a deficiency in 3-hydroxyisobutyrate dehydrogenase is the most likely cause of this disorder. Measurement of 3-hydroxyisobutyrate dehydrogenase activity in fibroblasts homogenates of the two newly identified patients and a previously reported patient, however, revealed similar activities as in control fibroblasts. Since other enzymes with overlapping substrate specificity could conceal abnormal 3-hydroxyisobutyrate dehydrogenase activity, we cloned a candidate human cDNA for 3-hydroxyisobutyrate dehydrogenase (HIBADH). By heterologous expression in Escherichia coli, we showed that the product of the HIBADH gene indeed displays 3-hydroxyisobutyrate dehydrogenase activity. Mutation analysis of the corresponding gene in the patients suffering from 3-hydroxyisobutyric aciduria revealed no mutations. We conclude that HIBADH is not the causative gene in 3-hydroxyisobutyric aciduria.
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Affiliation(s)
- Ference J Loupatty
- Department of Clinical Chemistry and Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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40
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Oey NA, Ruiter JPN, Attié-Bitach T, Ijlst L, Wanders RJA, Wijburg FA. Fatty acid oxidation in the human fetus: implications for fetal and adult disease. J Inherit Metab Dis 2006; 29:71-5. [PMID: 16601871 DOI: 10.1007/s10545-006-0199-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 12/02/2005] [Indexed: 11/28/2022]
Abstract
Studies in the last few years have shown a remarkably high activity of fatty acid oxidation (FAO) enzymes in human placenta. We have recently shown mRNA expression as well as enzymatic activity of long-chain FAO enzymes in the human embryo and fetus. In this study we show activity of the FAO enzymes carnitine palmitoyltranferase 1, medium-chain acyl-CoA dehydrogenase and short-chain hydroxyacyl-CoA dehydrogenase in embryonic and fetal tissues. In addition, we show the presence of different acylcarnitines in fetal liver and kidney, which substantiates the notion that the mitochondrial FAO enzymes are not only present in human fetal tissues but also metabolically active. In a glucose-rich environment FAO might be necessary for additional ATP production from fatty acids, but also for the breakdown of fatty acids that are products of the turnover of membranes in the growing fetus. The importance of FAO in the human embryo and fetus is further stressed by the fact that a higher frequency of prematurity, intrauterine growth retardation, fetal morbidity and intrauterine death is noted in long-chain FAO defects. Furthermore, in animal studies, gestational loss during early embryonic development has been observed as a consequence of disturbed FAO. Finally, there are indications that regulation of activity of FAO during fetal development might not only be important for fetal life but may also have implications for health and disease in adulthood.
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Affiliation(s)
- Nadia A Oey
- Department of Pediatrics, G8-205, Emma Children's Hospital AMC, Academic Medical Centre, PO Box 22660, NL-1100 DD, Amsterdam, The Netherlands
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41
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Das AM, Illsinger S, Lücke T, Hartmann H, Ruiter JPN, Steuerwald U, Waterham HR, Duran M, Wanders RJA. Isolated mitochondrial long-chain ketoacyl-CoA thiolase deficiency resulting from mutations in the HADHB gene. Clin Chem 2006; 52:530-4. [PMID: 16423905 DOI: 10.1373/clinchem.2005.062000] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The human mitochondrial trifunctional protein (MTP) complex is composed of 4 hydroacyl-CoA dehydrogenase-alpha (HADHA) and 4 hydroacyl-CoA dehydrogenase-beta (HADHB) subunits, which catalyze the last 3 steps in the fatty acid beta-oxidation spiral of long-chain fatty acids. The HADHB gene encodes long-chain ketoacyl-CoA thiolase (LCTH) activity, whereas the HADHA gene contains the information for the long-chain enoyl-CoA hydratase and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) functions. At present, 2 different biochemical phenotypes of defects in the mitochondrial trifunctional protein complex are known: isolated LCHAD deficiency and generalized MTP deficiency, with decreased activities of all 3 enzymes. Isolated LCTH deficiency with mutations in the HADHB gene has not been reported. PATIENT AND RESULTS We report a male newborn who presented with lactic acidosis, pulmonary edema, and cardiomyopathy leading to acute heart failure and death at the age of 6 weeks. Routine newborn screening by tandem mass spectrometry showed increased concentrations of the acylcarnitines tetradecenoylcarnitine, hexadecenoylcarnitine, hydroxypalmitoylcarnitine, and hydroxyoctadecenoylcarnitine, suggesting LCHAD deficiency or complete MTP deficiency. Enzyme investigations revealed very low LCTH (4% of normal) and normal LCHAD activities, whereas molecular analysis showed compound heterozygosity for 185G > A (R62H) and 1292T > C (F431S) mutations in the HADHB gene. CONCLUSION We describe the first case of isolated LCTH deficiency based on a mutation in the HADHB gene.
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Affiliation(s)
- Anibh M Das
- Department of Paediatrics, Hannover Medical School, Hannover, Germany.
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42
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Madsen PP, Kibaek M, Roca X, Sachidanandam R, Krainer AR, Christensen E, Steiner RD, Gibson KM, Corydon TJ, Knudsen I, Wanders RJA, Ruiter JPN, Gregersen N, Andresen BS. Short/branched-chain acyl-CoA dehydrogenase deficiency due to an IVS3+3A>G mutation that causes exon skipping. Hum Genet 2005; 118:680-90. [PMID: 16317551 DOI: 10.1007/s00439-005-0070-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Accepted: 08/31/2005] [Indexed: 12/23/2022]
Abstract
Short/branched-chain acyl-CoA dehydrogenase deficiency (SBCADD) is an autosomal recessive disorder of L: -isoleucine catabolism. Little is known about the clinical presentation associated with this enzyme defect, as it has been reported in only a limited number of patients. Because the presence of C5-carnitine in blood may indicate SBCADD, the disorder may be detected by MS/MS-based routine newborn screening. It is, therefore, important to gain more knowledge about the clinical presentation and the mutational spectrum of SBCADD. In the present study, we have studied two unrelated families with SBCADD, both with seizures and psychomotor delay as the main clinical features. One family illustrates the fact that affected individuals may also remain asymptomatic. In addition, the normal level of newborn blood spot C5-acylcarnitine in one patient underscores the fact that newborn screening by MS/MS currently lacks sensitivity in detecting SBCADD. Until now, seven mutations in the SBCAD gene have been reported, but only three have been tested experimentally. Here, we identify and characterize an IVS3+3A>G mutation (c.303+3A>G) in the SBCAD gene, and provide evidence that this mutation is disease-causing in both families. Using a minigene approach, we show that the IVS3+3A>G mutation causes exon 3 skipping, despite the fact that it does not appear to disrupt the consensus sequence of the 5' splice site. Based on these results and numerous literature examples, we suggest that this type of mutation (IVS+3A>G) induces missplicing only when in the context of non-consensus (weak) 5' splice sites. Statistical analysis of the sequences shows that the wild-type versions of 5' splice sites in which +3A>G mutations cause exon skipping and disease are weaker on average than a random set of 5' splice sites. This finding is relevant to the interpretation of the functional consequences of this type of mutation in other disease genes.
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Affiliation(s)
- Pia Pinholt Madsen
- Research Unit for Molecular Medicine, Aarhus University Hospital and Faculty of Health Science, Skejby Sygehus, Aarhus, Denmark
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43
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Djouadi F, Aubey F, Schlemmer D, Ruiter JPN, Wanders RJA, Strauss AW, Bastin J. Bezafibrate increases very-long-chain acyl-CoA dehydrogenase protein and mRNA expression in deficient fibroblasts and is a potential therapy for fatty acid oxidation disorders. Hum Mol Genet 2005; 14:2695-703. [PMID: 16115821 DOI: 10.1093/hmg/ddi303] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Inherited defect in very-long-chain acyl-CoA dehydrogenase (VLCAD), a mitochondrial enzyme catalyzing the initial step of long-chain fatty acid beta-oxidation (FAO), is one of the most frequent FAO enzyme defects. VLCAD deficiency is associated with clinical manifestations varying in severity, tissue involvement and age of onset. The molecular basis of VLCAD deficiency has been elucidated but therapeutic approaches are quite limited. In this study, we tested the hypothesis that fibrates, acting as agonist of peroxisome proliferator-activated receptors (PPARs), might stimulate FAO in VLCAD-deficient cells. We demonstrate that addition of bezafibrate or fenofibric acid in the culture medium induced a dose-dependent (up to 3-fold) increase in palmitate oxidation capacities in cells from patients with the myopathic form of VLCAD deficiency, but not in cells from severely affected patients. Complete normalization of cell FAO capacities could be achieved after exposure to 500 microm bezafibrate for 48 h. Cell therapy of VLCAD deficiency was related to drug-induced increases in VLCAD mRNA (+44 to +150%; P<0.001), protein (1.5-2-fold) and residual enzyme activity (up to 7.7-fold) in patient cells. Bezafibrate also diminished the production of toxic long-chain acylcarnitines by 90% in cells harboring moderate VLCAD deficiency. Finally, real-time PCR studies indicated that bezafibrate potentially stimulated gene expression of other enzymes in the beta-oxidation pathway. These data highlight the potential of fibrates in the correction of inborn FAO defects, as most mutations associated with these defects are compatible with the synthesis of a mutant protein with variable levels of residual enzyme activity.
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MESH Headings
- Acyl-CoA Dehydrogenase, Long-Chain/deficiency
- Acyl-CoA Dehydrogenase, Long-Chain/genetics
- Acyl-CoA Dehydrogenase, Long-Chain/metabolism
- Bezafibrate/pharmacology
- Bezafibrate/therapeutic use
- Blotting, Western
- Carnitine/analogs & derivatives
- Carnitine/metabolism
- DNA Primers
- Dose-Response Relationship, Drug
- Fibroblasts
- Gene Expression Regulation, Enzymologic/drug effects
- Humans
- Lipid Metabolism, Inborn Errors/drug therapy
- Lipid Metabolism, Inborn Errors/genetics
- Lipid Metabolism, Inborn Errors/metabolism
- Mitochondria/enzymology
- Mutation, Missense/genetics
- Palmitates/metabolism
- Peroxisome Proliferator-Activated Receptors/antagonists & inhibitors
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- F Djouadi
- INSERM U393, Hôpital Necker-Enfants Malades, Paris 75015, France
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44
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Oey NA, den Boer MEJ, Wijburg FA, Vekemans M, Augé J, Steiner C, Wanders RJA, Waterham HR, Ruiter JPN, Attié-Bitach T. Long-chain fatty acid oxidation during early human development. Pediatr Res 2005; 57:755-9. [PMID: 15845636 DOI: 10.1203/01.pdr.0000161413.42874.74] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Patients with very long-chain acyl-CoA dehydrogenase (VLCAD) and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD)/mitochondrial trifunctional protein (MTP) deficiency, disorders of the mitochondrial long-chain fatty acid oxidation, can present with hypoketotic hypoglycemia, rhabdomyolysis, and cardiomyopathy. In addition, patients with LCHAD/MTP deficiency may suffer from retinopathy and peripheral neuropathy. Until recently, there was no indication of intrauterine morbidity in these disorders. This observation was in line with the widely accepted view that fatty acid oxidation (FAO) does not play a significant role during fetal life. However, the high incidence of the gestational complications acute fatty liver of pregnancy and hemolysis, elevated liver enzymes, and low platelets syndrome observed in mothers carrying a LCHAD/MTP-deficient child and the recent reports of fetal hydrops due to cardiomyopathy in MTP deficiency, as well as the high incidence of intrauterine growth retardation in children with LCHAD/MTP deficiency, suggest that FAO may play an important role during fetal development. In this study, using in situ hybridization of the VLCAD and the LCHAD mRNA, we report on the expression of genes involved in the mitochondrial oxidation of long-chain fatty acids during early human development. Furthermore, we measured the enzymatic activity of the VLCAD, LCHAD, and carnitine palmitoyl-CoA transferase 2 (CPT2) enzymes in different human fetal tissues. Human embryos (at d 35 and 49 of development) and separate tissues (5-20 wk of development) were used. The results show a strong expression of VLCAD and LCHAD mRNA and a high enzymatic activity of VLCAD, LCHAD, and CPT2 in a number of tissues, such as liver and heart. In addition, high expression of LCHAD mRNA was observed in the neural retina and CNS. The observed pattern of expression during early human development is well in line with the spectrum of clinical signs and symptoms reported in patients with VLCAD or LCHAD/MTP deficiency.
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Affiliation(s)
- Nadia A Oey
- Department of Pediatrics, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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45
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Gloerich J, van Vlies N, Jansen GA, Denis S, Ruiter JPN, van Werkhoven MA, Duran M, Vaz FM, Wanders RJA, Ferdinandusse S. A phytol-enriched diet induces changes in fatty acid metabolism in mice both via PPARalpha-dependent and -independent pathways. J Lipid Res 2005; 46:716-26. [PMID: 15654129 DOI: 10.1194/jlr.m400337-jlr200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Branched-chain fatty acids (such as phytanic and pristanic acid) are ligands for the nuclear hormone receptor peroxisome proliferator-activated receptor alpha (PPARalpha) in vitro. To investigate the effects of these physiological compounds in vivo, wild-type and PPARalpha-deficient (PPARalpha-/-) mice were fed a phytol-enriched diet. This resulted in increased plasma and liver levels of the phytol metabolites phytanic and pristanic acid. In wild-type mice, plasma fatty acid levels decreased after phytol feeding, whereas in PPARalpha-/- mice, the already elevated fatty acid levels increased. In addition, PPARalpha-/- mice were found to be carnitine deficient in both plasma and liver. Dietary phytol increased liver free carnitine in wild-type animals but not in PPARalpha-/- mice. Investigation of carnitine biosynthesis revealed that PPARalpha is likely involved in the regulation of carnitine homeostasis. Furthermore, phytol feeding resulted in a PPARalpha-dependent induction of various peroxisomal and mitochondrial beta-oxidation enzymes. In addition, a PPARalpha-independent induction of catalase, phytanoyl-CoA hydroxylase, carnitine octanoyltransferase, peroxisomal 3-ketoacyl-CoA thiolase, and straight-chain acyl-CoA oxidase was observed. In conclusion, branched-chain fatty acids are physiologically relevant ligands of PPARalpha in mice. These findings are especially relevant for disorders in which branched-chain fatty acids accumulate, such as Refsum disease and peroxisome biogenesis disorders.
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Affiliation(s)
- J Gloerich
- University of Amsterdam, Academic Medical Center, Departments of Clinical Chemistry and Pediatrics, Laboratory for Genetic Metabolic Diseases, 1100 DE Amsterdam, The Netherlands
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46
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Loupatty FJ, Ruiter JPN, IJlst L, Duran M, Wanders RJA. Direct Nonisotopic Assay of 3-Methylglutaconyl-CoA Hydratase in Cultured Human Skin Fibroblasts to Specifically Identify Patients with 3-Methylglutaconic Aciduria Type I. Clin Chem 2004; 50:1447-50. [PMID: 15192029 DOI: 10.1373/clinchem.2004.033142] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ference J Loupatty
- Academic Medical Centre, Departments of Clinical Chemistry and Pediatrics, Emma Children's Hospital, University of Amsterdam, Amsterdam, The Netherlands
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47
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Poll-The BT, Wanders RJA, Ruiter JPN, Ofman R, Majoie CBLM, Barth PG, Duran M. Spastic diplegia and periventricular white matter abnormalities in 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency, a defect of isoleucine metabolism: differential diagnosis with hypoxic-ischemic brain diseases. Mol Genet Metab 2004; 81:295-9. [PMID: 15059617 DOI: 10.1016/j.ymgme.2003.11.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2003] [Revised: 11/17/2003] [Accepted: 11/17/2003] [Indexed: 01/15/2023]
Abstract
A 19-month-old boy with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase (MHBD) deficiency, a defect of isoleucine degradation, had cognitive and motor development delay, spastic diplegia, dysmorphism, and occipital periventricular white matter lesions on MRI scan of the brain. The urinary accumulation of the isoleucine metabolites 2-methyl-3-hydroxybutyrate and tiglylglycine was only moderate under basal conditions. These abnormalities became more pronounced after a 100mg/kg oral isoleucine challenge. Enzyme studies showed a markedly decreased activity of MHBD in fibroblasts and lymphocytes. Sequence analysis of the involved X-chromosome gene (HADH2), revealed the presence of 364C -->G mutation in the patient. His mother was heterozygous for the 364C-->G mutation, whereas the mutation was not found in the other members of the family (father, brother, and sister). This report indicates that an enzyme defect in the metabolism of branched-chain fatty acid oxidation and isoleucine may present features resembling sequelae of neonatal hypoxic-ischemic brain injury. All patients with MHBD deficiency identified so far are characterized by a neurologic phenotype rather than ketoacidotic attacks, unlike patients with the related isoleucine defect beta-ketothiolase deficiency.
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Affiliation(s)
- Bwee Tien Poll-The
- Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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48
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Ofman R, Ruiter JPN, Feenstra M, Duran M, Poll-The BT, Zschocke J, Ensenauer R, Lehnert W, Sass JO, Sperl W, Wanders RJA. 2-Methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency is caused by mutations in the HADH2 gene. Am J Hum Genet 2003; 72:1300-7. [PMID: 12696021 PMCID: PMC1180283 DOI: 10.1086/375116] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2002] [Accepted: 02/24/2003] [Indexed: 01/12/2023] Open
Abstract
2-methyl-3-hydroxybutyryl-CoA dehydrogenase (MHBD) deficiency is a novel inborn error of isoleucine degradation. In this article, we report the elucidation of the molecular basis of MHBD deficiency. To this end, we purified the enzyme from bovine liver. MALDI-TOF mass spectrometry analysis revealed that the purified protein was identical to bovine 3-hydroxyacyl-CoA dehydrogenase type II. The human homolog of this bovine enzyme is a short-chain 3-hydroxyacyl-CoA dehydrogenase, also known as the "endoplasmic reticulum-associated amyloid-beta binding protein" (ERAB). This led to the identification of the X-chromosomal gene involved, which previously had been denoted "HADH2." Sequence analysis of the HADH2 gene from patients with MHBD deficiency revealed the presence of two missense mutations (R130C and L122V). Heterologous expression of the mutant cDNAs in Escherichia coli showed that both mutations almost completely abolish enzyme activity. This confirms that MHBD deficiency is caused by mutations in the HADH2 gene.
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Affiliation(s)
- Rob Ofman
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Jos P. N. Ruiter
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Marike Feenstra
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Marinus Duran
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Bwee Tien Poll-The
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Johannes Zschocke
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Regina Ensenauer
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Willy Lehnert
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Jörn Oliver Sass
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Wolfgang Sperl
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
| | - Ronald J. A. Wanders
- Departments of Clinical Chemistry, Neurology, and Pediatrics, Academic Medical Center, Emma Children’s Hospital, University of Amsterdam, Amsterdam; Institute of Human Genetics, Heidelberg; Metabolic Unit, University Children’s Hospital, and Stoffwechsellabor, Zentrum für Kinderheilkunde und Jugendmedizin, Universitätsklinikum Freiburg, Freiburg, Germany; and Children’s Hospital LKA Salzburg, Salzburg
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49
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Oey NA, den Boer MEJ, Ruiter JPN, Wanders RJA, Duran M, Waterham HR, Boer K, van der Post JAM, Wijburg FA. High activity of fatty acid oxidation enzymes in human placenta: implications for fetal-maternal disease. J Inherit Metab Dis 2003; 26:385-92. [PMID: 12971426 DOI: 10.1023/a:1025163204165] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
As the human fetus and placenta are considered to be primarily dependent on glucose oxidation for energy metabolism, the cause of the remarkable association between severe maternal pregnancy complications and the carriage of a fetus with an inborn error of mitochondrial long-chain fatty acid oxidation (FAO) has remained obscure. We analysed human term placenta and chorionic villus samples for the activities of a variety of enzymes involved in FAO, and compared the results with those obtained in human liver. All enzymes were found to be expressed, with a very high activity of two enzymes involved in the metabolism of long-chain fatty acids (CPT2 and VLCAD), whereas the activity of medium-chain acyl-CoA dehydrogenase (MCAD) was found to be low, when compared to liver. These results suggest that fatty acid oxidation may play an important role in energy generation in human placenta, and that a deficiency in the placental oxidation of long-chain FAO may result in placental dysfunction, thus causing gestational complications.
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Affiliation(s)
- N A Oey
- Department of Paediatrics, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
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50
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IJlst L, Loupatty FJ, Ruiter JPN, Duran M, Lehnert W, Wanders RJA. 3-Methylglutaconic aciduria type I is caused by mutations in AUH. Am J Hum Genet 2002; 71:1463-6. [PMID: 12434311 PMCID: PMC378594 DOI: 10.1086/344712] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2002] [Accepted: 09/11/2002] [Indexed: 11/03/2022] Open
Abstract
3-Methylglutaconic aciduria type I is an autosomal recessive disorder clinically characterized by various symptoms ranging from delayed speech development to severe neurological handicap. This disorder is caused by a deficiency of 3-methylglutaconyl-CoA hydratase, one of the key enzymes of leucine degradation. This results in elevated urinary levels of 3-methylglutaconic acid, 3-methylglutaric acid, and 3-hydroxyisovaleric acid. By heterologous expression in Escherichia coli, we show that 3-methylglutaconyl-CoA hydratase is encoded by the AUH gene, whose product had been reported elsewhere as an AU-specific RNA-binding protein. Mutation analysis of AUH in two patients revealed a nonsense mutation (R197X) and a splice-site mutation (IVS8-1G-->A), demonstrating that mutations in AUH cause 3-methylglutaconic aciduria type I.
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Affiliation(s)
- Lodewijk IJlst
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
| | - Ference J. Loupatty
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
| | - Jos P. N. Ruiter
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
| | - Marinus Duran
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
| | - Willy Lehnert
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
| | - Ronald J. A. Wanders
- Departments of Clinical Chemistry and Pediatrics, Emma Children’s Hospital, Academic Medical Center, University of Amsterdam, Amsterdam; and University Children’s Hospital, Freiburg, Germany
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