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Seker Yilmaz B, Baruteau J, Chakrapani A, Champion M, Chronopoulou E, Claridge LC, Daly A, Davies C, Davison J, Dhawan A, Grunewald S, Gupte GL, Heaton N, Lemonde H, McKiernan P, Mills P, Morris AA, Mundy H, Pierre G, Rajwal S, Sivananthan S, Sreekantam S, Stepien KM, Vara R, Yeo M, Gissen P. Liver transplantation in ornithine transcarbamylase deficiency: A retrospective multicentre cohort study. Mol Genet Metab Rep 2023; 37:101020. [PMID: 38053940 PMCID: PMC10694733 DOI: 10.1016/j.ymgmr.2023.101020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 12/07/2023] Open
Abstract
Ornithine transcarbamylase deficiency (OTCD) is an X-linked defect of ureagenesis and the most common urea cycle disorder. Patients present with hyperammonemia causing neurological symptoms, which can lead to coma and death. Liver transplantation (LT) is the only curative therapy, but has several limitations including organ shortage, significant morbidity and requirement of lifelong immunosuppression. This study aims to identify the characteristics and outcomes of patients who underwent LT for OTCD. We conducted a retrospective study for OTCD patients from 5 UK centres receiving LT in 3 transplantation centres between 2010 and 2022. Patients' demographics, family history, initial presentation, age at LT, graft type and pre- and post-LT clinical, metabolic, and neurocognitive profile were collected from medical records. A total of 20 OTCD patients (11 males, 9 females) were enrolled in this study. 6/20 had neonatal and 14/20 late-onset presentation. 2/20 patients had positive family history for OTCD and one of them was diagnosed antenatally and received prospective treatment. All patients were managed with standard of care based on protein-restricted diet, ammonia scavengers and supplementation with arginine and/or citrulline before LT. 15/20 patients had neurodevelopmental problems before LT. The indication for LT was presence (or family history) of recurrent metabolic decompensations occurring despite standard medical therapy leading to neurodisability and quality of life impairment. Median age at LT was 10.5 months (6-24) and 66 months (35-156) in neonatal and late onset patients, respectively. 15/20 patients had deceased donor LT (DDLT) and 5/20 had living related donor LT (LDLT). Overall survival was 95% with one patient dying 6 h after LT. 13/20 had complications after LT and 2/20 patients required re-transplantation. All patients discontinued dietary restriction and ammonia scavengers after LT and remained metabolically stable. Patients who had neurodevelopmental problems before LT persisted to have difficulties after LT. 1/5 patients who was reported to have normal neurodevelopment before LT developed behavioural problems after LT, while the remaining 4 maintained their abilities without any reported issues. LT was found to be effective in correcting the metabolic defect, eliminates the risk of hyperammonemia and prolongs patients' survival.
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Affiliation(s)
- Berna Seker Yilmaz
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Julien Baruteau
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Anupam Chakrapani
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Michael Champion
- Department of Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH London, UK
| | - Efstathia Chronopoulou
- Department of Inherited Metabolic Disease, Division of Women's and Children's Services, University Hospitals Bristol NHS Foundation Trust, Bristol BS1 3NU, UK
| | | | - Anne Daly
- Birmingham Women's and Children's Hospital NHS Foundation Trust, B4 6NH, Birmingham, UK
| | - Catherine Davies
- Department of Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH London, UK
| | - James Davison
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Anil Dhawan
- Paediatric Liver Gastroenterology and Nutrition Centre and Mowat Labs, King's College Hospital NHS Foundation Trust, WC2R 2LS, London, UK
| | - Stephanie Grunewald
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Girish L. Gupte
- Birmingham Women's and Children's Hospital NHS Foundation Trust, B4 6NH, Birmingham, UK
| | - Nigel Heaton
- Institute of Liver Studies, Kings College Hospital, Denmark Hill, WC2R 2LS London, UK
| | - Hugh Lemonde
- Department of Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH London, UK
| | - Pat McKiernan
- Birmingham Women's and Children's Hospital NHS Foundation Trust, B4 6NH, Birmingham, UK
| | - Philippa Mills
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Andrew A.M. Morris
- Willink Unit, Genetic Medicine, Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Oxford Road, Manchester M13 9WL, UK
| | - Helen Mundy
- Department of Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH London, UK
| | - Germaine Pierre
- Department of Inherited Metabolic Disease, Division of Women's and Children's Services, University Hospitals Bristol NHS Foundation Trust, Bristol BS1 3NU, UK
| | - Sanjay Rajwal
- Leeds Teaching Hospitals NHS Trust, LS9 7TF Leeds, UK
| | - Siyamini Sivananthan
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Srividya Sreekantam
- Birmingham Women's and Children's Hospital NHS Foundation Trust, B4 6NH, Birmingham, UK
| | - Karolina M. Stepien
- Adult Inherited Metabolic Diseases, Salford Royal NHS Foundation Trust, M6 8HD Salford, UK
| | - Roshni Vara
- Department of Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH London, UK
| | - Mildrid Yeo
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Paul Gissen
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Department of Paediatric Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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2
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Seker Yilmaz B, Gissen P. Genetic Therapy Approaches for Ornithine Transcarbamylase Deficiency. Biomedicines 2023; 11:2227. [PMID: 37626723 PMCID: PMC10452060 DOI: 10.3390/biomedicines11082227] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/06/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Ornithine transcarbamylase deficiency (OTCD) is the most common urea cycle disorder with high unmet needs, as current dietary and medical treatments may not be sufficient to prevent hyperammonemic episodes, which can cause death or neurological sequelae. To date, liver transplantation is the only curative choice but is not widely available due to donor shortage, the need for life-long immunosuppression and technical challenges. A field of research that has shown a great deal of promise recently is gene therapy, and OTCD has been an essential candidate for different gene therapy modalities, including AAV gene addition, mRNA therapy and genome editing. This review will first summarise the main steps towards clinical translation, highlighting the benefits and challenges of each gene therapy approach, then focus on current clinical trials and finally outline future directions for the development of gene therapy for OTCD.
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Affiliation(s)
- Berna Seker Yilmaz
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK;
| | - Paul Gissen
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK;
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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3
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Forsyth R, Peretz RH, Dempsey A, Britton J, Kratz L, Hamosh A, Vernon H, Batshaw ML, Valle D. The remarkable journey of one female individual with ornithine transcarbamylase deficiency diagnosed post-mortem. JIMD Rep 2023; 64:233-237. [PMID: 37151362 PMCID: PMC10159862 DOI: 10.1002/jmd2.12361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 01/12/2023] [Accepted: 01/16/2023] [Indexed: 01/31/2023] Open
Abstract
Urea cycle disorders (UCDs) comprise a group of inborn errors of metabolism with impaired ammonia clearance and an incidence of ~1:35 000 individuals. First described in the 1970s, the diagnosis and management of these disorders has evolved dramatically. We report on a 59-year-old woman with a UCD who contributed to advances in the understanding and treatment of this group of disorders. This individual was diagnosed with carbamoyl phosphate synthetase 1 deficiency based on a biochemical assay under a research context predating genetic sequencing, treated longitudinally as having this metabolic disorder, and was among the first participants to trial UCD pharmaceutical therapies. She ultimately succumbed to a SARS-CoV-2 infection while maintaining unexpectedly normal ammonium levels. Postmortem genetic testing revealed ornithine transcarbamylase deficiency. This individual's contributions to the field of UCDs is discussed herein.
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Affiliation(s)
- RaeLynn Forsyth
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Ryan H. Peretz
- National Human Genome Research InstituteNational Institutes of HealthBethesdaMarylandUSA
| | - Angela Dempsey
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Jacquelyn Britton
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Lisa Kratz
- Biochemical Genetics LaboratoryKennedy Krieger InstituteBaltimoreMarylandUSA
| | - Ada Hamosh
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Hilary Vernon
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Mark L. Batshaw
- Center for Genetic Medicine ResearchChildren's National HospitalWashingtonDCUSA
| | - David Valle
- Department of Genetic MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
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Mirdamadi ES, Khosrowpour Z, Jafari D, Gholipourmalekabadi M, Solati-Hashjin M. 3D-printed PLA/Gel hybrid in liver tissue engineering: Effects of architecture on biological functions. Biotechnol Bioeng 2023; 120:836-851. [PMID: 36479982 DOI: 10.1002/bit.28301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/28/2022] [Accepted: 12/04/2022] [Indexed: 12/13/2022]
Abstract
The liver is one of the vital organs in the body, and the gold standard of treatment for liver function impairment is liver transplantation, which poses many challenges. The specific three-dimensional (3D) structure of liver, which significantly impacts the growth and function of its cells, has made biofabrication with the 3D printing of scaffolds suitable for this approach. In this study, to investigate the effect of scaffold geometry on the performance of HepG2 cells, poly-lactic acid (PLA) polymer was used as the input of the fused deposition modeling (FDM) 3D-printing machine. Samples with simple square and bioinspired hexagonal cross-sectional designs were printed. One percent and 2% of gelatin coating were applied to the 3D printed PLA to improve the wettability and surface properties of the scaffold. Scanning electron microscopy pictures were used to analyze the structural properties of PLA-Gel hybrid scaffolds, energy dispersive spectroscopy to investigate the presence of gelatin, water contact angle measurement for wettability, and weight loss for degradation. In vitro tests were performed by culturing HepG2 cells on the scaffold to evaluate the cell adhesion, viability, cytotoxicity, and specific liver functions. Then, high-precision scaffolds were printed and the presence of gelatin was detected. Also, the effect of geometry on cell function was confirmed in viability, adhesion, and functional tests. The albumin and urea production of the Hexagonal PLA scaffold was about 1.22 ± 0.02-fold higher than the square design in 3 days. This study will hopefully advance our understanding of liver tissue engineering toward a promising perspective for liver regeneration.
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Affiliation(s)
- Elnaz Sadat Mirdamadi
- BioFabrication Lab (BFL), Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.,Department of Biomedical Engineering, University of Connecticut, Storrs, Connecticut, USA
| | - Zahra Khosrowpour
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran.,Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Davod Jafari
- Department of Medical Biotechnology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mazaher Gholipourmalekabadi
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran.,Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran.,Department of Medical Biotechnology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mehran Solati-Hashjin
- BioFabrication Lab (BFL), Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
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5
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García Vega M, Andrade JD, Morais A, Frauca E, Muñoz Bartolo G, Lledín MD, Bergua A, Hierro L. Urea cycle disorders and indications for liver transplantation. Front Pediatr 2023; 11:1103757. [PMID: 36937980 PMCID: PMC10020209 DOI: 10.3389/fped.2023.1103757] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 02/01/2023] [Indexed: 03/06/2023] Open
Abstract
Urea cycle disorders (UCD) are inborn errors of metabolism caused by deficiency of enzymes required to convert nitrogen from ammonia into urea. Current paradigms of treatment focus on dietary manipulations, ammonia scavenger drugs, and liver transplantation. The aim of this study was to describe the characteristics and indication of liver transplantation in UCD in a tertiary hospital. We performed a retrospective study of children with UCD seen in the period 2000-2021. Data was collected on clinical onset, hyperammonemia severity, evolution and liver transplantation. There were 33 patients in the study period, whose diagnosis were: ornithine transcarbamylase (OTC, n = 20, 10 females), argininosuccinate synthetase (ASS, n = 6), carbamylphosphate synthetase 1 (CPS1, n = 4), argininosuccinate lyase (ASL, n = 2) and N-acetylglutamate synthetase (NAGS, n = 1) deficiency. Thirty one were detected because of clinical symptoms (45% with neonatal onset). The other 2 were diagnosed being presymptomatic, by neonatal/family screening. Neonatal forms (n = 14) were more severe, all of them presented during the first week of life as severe hyperammonemia (mean peak 1,152 µmol/L). Seven patients died (6 at debut) and all survivors received transplantation. There was no mortality among the late forms. Of the 27 patients who did not die in the neonatal period, 16 (59%) received liver transplantationwith 100% survival, normal protein tolerance and usual need of citrulline supplementation. The transplant's metabolic success was accompanied by neurologic sequelae in 69%, but there was no progression of brain damage. Decision of continuous medical treatment in 11 patients appeared to be related with preserved neurodevelopment and fewer metabolic crises.
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Affiliation(s)
- Marta García Vega
- Department of Pediatric Hepatology & Liver Transplant, Hospital Universitario La Paz & IdiPAZ, ERN Rare-Liver, ERN Trasplant Child, Madrid, Spain
- Correspondence: Marta García Vega
| | - José D. Andrade
- Department of Pediatric Nutrition and Metabolic Diseases, Hospital Universitario La Paz, Madrid, Spain
| | - Ana Morais
- Department of Pediatric Nutrition and Metabolic Diseases, Hospital Universitario La Paz, Madrid, Spain
| | - Esteban Frauca
- Department of Pediatric Hepatology & Liver Transplant, Hospital Universitario La Paz & IdiPAZ, ERN Rare-Liver, ERN Trasplant Child, Madrid, Spain
| | - Gema Muñoz Bartolo
- Department of Pediatric Hepatology & Liver Transplant, Hospital Universitario La Paz & IdiPAZ, ERN Rare-Liver, ERN Trasplant Child, Madrid, Spain
| | - María D. Lledín
- Department of Pediatric Hepatology & Liver Transplant, Hospital Universitario La Paz & IdiPAZ, ERN Rare-Liver, ERN Trasplant Child, Madrid, Spain
| | - Ana Bergua
- Department of Pediatric Nutrition and Metabolic Diseases, Hospital Universitario La Paz, Madrid, Spain
| | - Loreto Hierro
- Department of Pediatric Hepatology & Liver Transplant, Hospital Universitario La Paz & IdiPAZ, ERN Rare-Liver, ERN Trasplant Child, Madrid, Spain
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6
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Seker Yilmaz B, Baruteau J, Arslan N, Aydin HI, Barth M, Bozaci AE, Brassier A, Canda E, Cano A, Chronopoulou E, Connolly GM, Damaj L, Dawson C, Dobbelaere D, Douillard C, Eminoglu FT, Erdol S, Ersoy M, Fang S, Feillet F, Gokcay G, Goksoy E, Gorce M, Inci A, Kadioglu B, Kardas F, Kasapkara CS, Kilic Yildirim G, Kor D, Kose M, Marelli C, Mundy H, O’Sullivan S, Ozturk Hismi B, Ramachandran R, Roubertie A, Sanlilar M, Schiff M, Sreekantam S, Stepien KM, Uzun Unal O, Yildiz Y, Zubarioglu T, Gissen P. Three-Country Snapshot of Ornithine Transcarbamylase Deficiency. Life (Basel) 2022; 12:1721. [PMID: 36362876 PMCID: PMC9695856 DOI: 10.3390/life12111721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/24/2022] [Accepted: 10/25/2022] [Indexed: 11/16/2022] Open
Abstract
X-linked ornithine transcarbamylase deficiency (OTCD) is the most common urea cycle defect. The disease severity ranges from asymptomatic carrier state to severe neonatal presentation with hyperammonaemic encephalopathy. We audited the diagnosis and management of OTCD, using an online 12-question-survey that was sent to 75 metabolic centres in Turkey, France and the UK. Thirty-nine centres responded and 495 patients were reported in total. A total of 208 French patients were reported, including 71 (34%) males, 86 (41%) symptomatic and 51 (25%) asymptomatic females. Eighty-five Turkish patients included 32 (38%) males, 39 (46%) symptomatic and 14 (16%) asymptomatic females. Out of the 202 UK patients, 66 (33%) were male, 83 (41%) asymptomatic and 53 (26%) symptomatic females. A total of 19%, 12% and 7% of the patients presented with a neonatal-onset phenotype in France, Turkey and the UK, respectively. Vomiting, altered mental status and encephalopathy were the most common initial symptoms in all three countries. While 69% in France and 79% in Turkey were receiving protein restriction, 42% were on a protein-restricted diet in the UK. A total of 76%, 47% and 33% of patients were treated with ammonia scavengers in Turkey, France and the UK, respectively. The findings of our audit emphasize the differences and similarities in manifestations and management practices in three countries.
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Affiliation(s)
- Berna Seker Yilmaz
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Julien Baruteau
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Nur Arslan
- Paediatric Metabolic Medicine Department, Dokuz Eylul University Faculty of Medicine, Izmir 35340, Turkey
| | - Halil Ibrahim Aydin
- Paediatric Metabolic Medicine Department, Baskent University Faculty of Medicine, Ankara 06490, Turkey
| | - Magalie Barth
- Centre de Référence des Maladies Héréditaires du Métabolisme, CHU Angers, 4 rue Larrey, CEDEX 9, 49933 Angers, France
| | - Ayse Ergul Bozaci
- Paediatric Metabolic Medicine Department, Diyarbakir Children’s Hospital, Diyarbakir 21100, Turkey
| | - Anais Brassier
- Reference Center for Inborn Errors of Metabolism, Necker University Hospital, APHP and University of Paris Cité, 75015 Paris, France
| | - Ebru Canda
- Paediatric Metabolic Medicine Department, Ege University Faculty of Medicine, Izmir 35100, Turkey
| | - Aline Cano
- Reference Center of Inherited Metabolic Disorders, Timone Enfants Hospital, 264 rue Saint-Pierre, 13005 Marseille, France
| | - Efstathia Chronopoulou
- Department of Inherited Metabolic Disease, Division of Women’s and Children’s Services, University Hospitals Bristol NHS Foundation Trust, Bristol BS1 3NU, UK
| | | | - Lena Damaj
- Centre de Compétence Maladies Héréditaires du Métabolisme, CHU Hôpital Sud, CEDEX 2, 35203 Rennes, France
| | - Charlotte Dawson
- Metabolic Medicine Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2GW, UK
| | - Dries Dobbelaere
- Medical Reference Center for Inherited Metabolic Diseases, Jeanne de Flandre University Hospital and RADEME Research Team for Rare Metabolic and Developmental Diseases, EA 7364 CHRU Lille, 59000 Lille, France
| | - Claire Douillard
- Medical Reference Center for Inherited Metabolic Diseases, Jeanne de Flandre University Hospital and RADEME Research Team for Rare Metabolic and Developmental Diseases, EA 7364 CHRU Lille, 59000 Lille, France
| | - Fatma Tuba Eminoglu
- Paediatric Metabolic Medicine Department, Ankara University Faculty of Medicine, Ankara 06080, Turkey
| | - Sahin Erdol
- Paediatric Metabolic Medicine Department, Uludag University Faculty of Medicine, Bursa 16059, Turkey
| | - Melike Ersoy
- Paediatric Metabolic Medicine Department, Dr Sadi Konuk Reseach & Training Hospital, Istanbul 34450, Turkey
| | - Sherry Fang
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - François Feillet
- Centre de Référence des Maladies Métaboliques de Nancy, CHU Brabois Enfants, 5 Rue du Morvan, 54500 Vandœuvre-lès-Nancy, France
| | - Gulden Gokcay
- Paediatric Metabolic Medicine Department, Istanbul University Istanbul Faculty of Medicine, Istanbul 34093, Turkey
| | - Emine Goksoy
- Paediatric Metabolic Medicine Department, Cengiz Gokcek Children’s Hospital, Gaziantep 27010, Turkey
| | - Magali Gorce
- Centre de Référence des Maladies Rares du Métabolisme, Hôpital des Enfants—CHU Toulouse, 330 Avenue de Grande-Bretagne, CEDEX 9, 31059 Toulouse, France
| | - Asli Inci
- Paediatric Metabolic Medicine Department, Gazi University Faculty of Medicine, Ankara 06500, Turkey
| | - Banu Kadioglu
- Paediatric Metabolic Medicine Department, Konya City Hospital, Konya 42020, Turkey
| | - Fatih Kardas
- Paediatric Metabolic Medicine Department, Erciyes University Faculty of Medicine, Kayseri 38030, Turkey
| | - Cigdem Seher Kasapkara
- Paediatric Metabolic Medicine Department, Ankara Yildirim Beyazit University Faculty of Medicine, Ankara 06800, Turkey
| | - Gonca Kilic Yildirim
- Paediatric Metabolic Medicine Department, Osmangazi University Faculty of Medicine, Eskisehir 26480, Turkey
| | - Deniz Kor
- Paediatric Metabolic Medicine Department, Cukurova University Faculty of Medicine, Adana 01250, Turkey
| | - Melis Kose
- Paediatric Metabolic Medicine Department, Faculty of Medicine, Izmir Katip Celebi University, Izmir 35620, Turkey
| | - Cecilia Marelli
- MMDN, University Montpellier, EPHE, INSERM, 34090 Montpellier, France
- Expert Center for Metabolic and Neurogenetic Diseases, Centre Hospitalier Universitaire (CHU), 34090 Montpellier, France
| | - Helen Mundy
- Evelina Children’s Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London SE1 7EH, UK
| | | | - Burcu Ozturk Hismi
- Paediatric Metabolic Medicine Department, Marmara University Faculty of Medicine, Istanbul 34854, Turkey
| | | | - Agathe Roubertie
- MMDN, University Montpellier, EPHE, INSERM, 34090 Montpellier, France
- Expert Center for Metabolic and Neurogenetic Diseases, Centre Hospitalier Universitaire (CHU), 34090 Montpellier, France
| | - Mehtap Sanlilar
- Paediatric Metabolic Medicine Department, Antalya Training and Research Hospital, Antalya 07100, Turkey
| | - Manuel Schiff
- Reference Center for Inborn Errors of Metabolism, Necker University Hospital, APHP and University of Paris Cité, 75015 Paris, France
| | - Srividya Sreekantam
- Birmingham Women’s and Children’s Hospital NHS Foundation Trust, Birmingham B4 6NH, UK
| | - Karolina M. Stepien
- Adult Inherited Metabolic Diseases, Salford Royal NHS Foundation Trust, Salford M6 8HD, UK
| | - Ozlem Uzun Unal
- Paediatric Metabolic Medicine Department, Kocaeli University Faculty of Medicine, Kocaeli 41380, Turkey
| | - Yilmaz Yildiz
- Paediatric Metabolic Medicine Department, Hacettepe University Faculty of Medicine, Ankara 06230, Turkey
| | - Tanyel Zubarioglu
- Paediatric Metabolic Medicine Department, Istanbul University-Cerrahpasa Faculty of Medicine, Istanbul 34096, Turkey
| | - Paul Gissen
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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7
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Jin X, Zeng X, Zhao D, Jiang N. Liver transplantation in rare late-onset ornithine transcarbamylase deficiency with central nervous system injury: A case report and review of the literature. Brain Behav 2022; 12:e2765. [PMID: 36128655 PMCID: PMC9575608 DOI: 10.1002/brb3.2765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/29/2022] [Accepted: 08/28/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Ornithine transcarbamylase deficiency (OTCD) is a genetic metabolic disease. Its clinical manifestations are mainly central nervous system dysfunction caused by high blood ammonia. Late-onset OTCD combined with central nervous system injury has a poor therapeutic response, which is one of the main factors affecting the prognosis and quality of life of patients. liver transplantation (LT) has gradually become a radical treatment for OTCD, which has achieved good results. However, there is no consensus on the timing of LT and problems of nervous system damage and repair. METHODS We report the development of late-onset OTCD with central nervous system injury in an 11-year-old child who received liver transplantation at our transplant center. His first symptoms were nonprojectile vomiting, followed by irritability and disturbance of consciousness, after which the disease progressed rapidly and finally resulted in a coma. After liver transplantation, the child's consciousness returned to normal, muscle strength of the limbs gradually recovered from grade 0 to grade 4, and muscle tone gradually recovered from grade 4 to grade 1, suggesting that the motor nerves had gradually recovered. However, the child is currently mentally retarded, and the language center has not yet fully recovered.At the same time, we made a literature review of OTCD. CONCLUSION For OTCD patients with central nervous system injury, liver transplantation can fundamentally solve the problem of ammonia metabolism in the liver and avoids further damage to the central nervous system caused by hyperammonemia. At the same time, children's nervous systems are in the developmental stage when neuroplasticity is greatest. If liver transplantation is performed as soon as possible, nerve repair is still possible.
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Affiliation(s)
- Xin Jin
- Division of Liver Surgery and Organ Transplantation Center, Shenzhen Third People's Hospital, Second Affiliated Hospital of Southern University of Science and Technology, National Clinical Research Center for Infectious Disease, Shenzhen, China
| | - Xinchen Zeng
- Division of Liver Surgery and Organ Transplantation Center, Shenzhen Third People's Hospital, Second Affiliated Hospital of Southern University of Science and Technology, National Clinical Research Center for Infectious Disease, Shenzhen, China
| | - Dong Zhao
- Division of Liver Surgery and Organ Transplantation Center, Shenzhen Third People's Hospital, Second Affiliated Hospital of Southern University of Science and Technology, National Clinical Research Center for Infectious Disease, Shenzhen, China
| | - Nan Jiang
- Division of Liver Surgery and Organ Transplantation Center, Shenzhen Third People's Hospital, Second Affiliated Hospital of Southern University of Science and Technology, National Clinical Research Center for Infectious Disease, Shenzhen, China
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8
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Mao X, Chen H, Lin AZ, Kim S, Burczynski ME, Na E, Halasz G, Sleeman MW, Murphy AJ, Okamoto H, Cheng X. Glutaminase 2 knockdown reduces hyperammonemia and associated lethality of urea cycle disorder mouse model. J Inherit Metab Dis 2022; 45:470-480. [PMID: 34988999 PMCID: PMC9302672 DOI: 10.1002/jimd.12474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 12/29/2021] [Accepted: 01/04/2022] [Indexed: 11/12/2022]
Abstract
Amino acids, the building blocks of proteins in the cells and tissues, are of fundamental importance for cell survival, maintenance, and proliferation. The liver plays a critical role in amino acid metabolism and detoxication of byproducts such as ammonia. Urea cycle disorders with hyperammonemia remain difficult to treat and eventually necessitate liver transplantation. In this study, ornithine transcarbamylase deficient (Otcspf-ash ) mouse model was used to test whether knockdown of a key glutamine metabolism enzyme glutaminase 2 (GLS2, gene name: Gls2) or glutamate dehydrogenase 1 (GLUD1, gene name: Glud1) could rescue the hyperammonemia and associated lethality induced by a high protein diet. We found that reduced hepatic expression of Gls2 but not Glud1 by AAV8-mediated delivery of a short hairpin RNA in Otcspf-ash mice diminished hyperammonemia and reduced lethality. Knockdown of Gls2 but not Glud1 in Otcspf-ash mice exhibited reduced body weight loss and increased plasma glutamine concentration. These data suggest that Gls2 hepatic knockdown could potentially help alleviate risk for hyperammonemia and other clinical manifestations of patients suffering from defects in the urea cycle.
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Affiliation(s)
- Xia Mao
- Regeneron PharmaceuticalsTarrytownNew YorkUSA
| | - Helen Chen
- Regeneron PharmaceuticalsTarrytownNew YorkUSA
| | | | - Sun Kim
- Regeneron PharmaceuticalsTarrytownNew YorkUSA
| | | | - Erqian Na
- Regeneron PharmaceuticalsTarrytownNew YorkUSA
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9
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Pritchard AB, Izumi K, Payan‐Walters I, Yudkoff M, Rand EB, Bhoj E. Inborn error of metabolism patients after liver transplantation: Outcomes of 35 patients over 27 years in one pediatric quaternary hospital. Am J Med Genet A 2022; 188:1443-1447. [DOI: 10.1002/ajmg.a.62659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/22/2021] [Accepted: 01/01/2022] [Indexed: 01/25/2023]
Affiliation(s)
- Amanda Barone Pritchard
- Division of Pediatric Genetics, Metabolism, and Genomic Medicine, Department of Pediatrics C.S. Mott Children's Hospital, Michigan Medicine Ann Arbor Michigan USA
| | - Kosuke Izumi
- Division of Human Genetics, Department of Pediatrics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
| | - Irma Payan‐Walters
- Division of Human Genetics, Department of Pediatrics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
| | - Marc Yudkoff
- Division of Human Genetics, Department of Pediatrics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
| | - Elizabeth B. Rand
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
| | - Elizabeth Bhoj
- Division of Human Genetics, Department of Pediatrics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
- Center for Applied Genomics The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
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10
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Choi Y, Oh A, Lee Y, Kim GH, Choi JH, Yoo HW, Lee BH. Unfavorable clinical outcomes in patients with carbamoyl phosphate synthetase 1 deficiency. Clin Chim Acta 2021; 526:55-61. [PMID: 34973183 DOI: 10.1016/j.cca.2021.11.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/22/2021] [Accepted: 11/30/2021] [Indexed: 12/31/2022]
Abstract
PURPOSE Carbamoyl phosphate synthetase 1 (CPS1) deficiency affects the first step of urea cycle and is a severe form of urea cycle disorder (UCD). The severity of hyperammonemic encephalopathy determines the clinical course of UCDs. Here, we describe the genetic and clinical characteristics of CPS1 deficiency in Korea. PATIENT AND METHODS This study included seven patients with CPS1 deficiency genetically confirmed from January 1992 to September 2020. The peak ammonia level during the first crisis, the half time of peak ammonia level, the initial plasma amino acid levels, and neurological outcomes were compared between CPS1 deficiency and two common UCDs (i.e., 17 patients with argininosuccinate synthetase 1 deficiency and 24 patients with ornithine transcarbamylase deficiency). RESULT Eleven CPS1 mutations were identified, including 10 novel mutations. Eight mutations were missense. Six patients with CPS1 deficiency had neonatal type. The peak ammonia level, initial glutamate level, and accompanying rate of irreversible neurological damages were highest in patients with CPS1 deficiency. The patient with late-onset CPS1 deficiency responded dramatically to N-carbamylglutamate treatment. CONCLUSION The clinical manifestations of CPS1 deficiency were the most severe among UCDs. Considering the high proportion of missense mutations, responsiveness to N-carbamylglutamate would be evaluated in a future study.
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Affiliation(s)
- Yunha Choi
- Department of Pediatrics, Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Arum Oh
- Department of Pediatrics, Chungbuk National University Hospital, Chungbuk National University College of Medicine, Cheongju, South Korea
| | - Yena Lee
- Department of Pediatrics, Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Gu-Hwan Kim
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Jin-Ho Choi
- Department of Pediatrics, Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Han-Wook Yoo
- Department of Pediatrics, Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea; Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Beom Hee Lee
- Department of Pediatrics, Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea; Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea.
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11
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Baruteau J, Cunningham SC, Yilmaz BS, Perocheau DP, Eaglestone S, Burke D, Thrasher AJ, Waddington SN, Lisowski L, Alexander IE, Gissen P. Safety and efficacy of an engineered hepatotropic AAV gene therapy for ornithine transcarbamylase deficiency in cynomolgus monkeys. Mol Ther Methods Clin Dev 2021; 23:135-146. [PMID: 34703837 PMCID: PMC8517016 DOI: 10.1016/j.omtm.2021.09.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 09/08/2021] [Indexed: 12/31/2022]
Abstract
X-linked inherited ornithine transcarbamylase deficiency (OTCD) is the most common disorder affecting the liver-based urea cycle, a pathway enabling detoxification of nitrogen waste and endogenous arginine biosynthesis. Patients develop acute hyperammonemia leading to neurological sequelae or death despite the best-accepted therapy based on ammonia scavengers and protein-restricted diet. Liver transplantation is curative but associated with procedure-related complications and lifelong immunosuppression. Adeno-associated viral (AAV) vectors have demonstrated safety and clinical benefits in a rapidly growing number of clinical trials for inherited metabolic liver diseases. Engineered AAV capsids have shown promising enhanced liver tropism. Here, we conducted a good-laboratory practice-compliant investigational new drug-enabling study to assess the safety of intravenous liver-tropic AAVLK03 gene transfer of a human codon-optimized OTC gene. Juvenile cynomolgus monkeys received vehicle and a low and high dose of vector (2 × 1012 and 2 × 1013 vector genome (vg)/kg, respectively) and were monitored for 26 weeks for in-life safety with sequential liver biopsies at 1 and 13 weeks post-vector administration. Upon completion of monitoring, animals were euthanized to study vector biodistribution, immune responses, and histopathology. The product was well tolerated with no adverse clinical events, predominant hepatic biodistribution, and sustained supra-physiological OTC overexpression. This study supports the clinical deployment of intravenous AAVLK03 for severe OTCD.
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Affiliation(s)
- Julien Baruteau
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- National Institute of Health Research, Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Sharon C. Cunningham
- Gene Therapy Research Unit, Children’s Medical Research Institute and Children’s Hospital at Westmead, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Berna Seker Yilmaz
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Department of Pediatric Metabolic Medicine, Mersin University, Mersin 33110, Turkey
| | - Dany P. Perocheau
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Simon Eaglestone
- Translational Research Office, University College London, London, UK
| | - Derek Burke
- Enzyme Unit, NIHR BRC, Great Ormond Street Hospital Foundation Trust and UCL Great Ormond Street Institute of Child Health, London, UK
| | - Adrian J. Thrasher
- Molecular & Cellular Immunology, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Simon N. Waddington
- Gene Transfer Technology Group, Institute for Women’s Health, University College London, 86-96 Chenies Mews, London, UK
- MRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witswatersrand, Johannesburg, South Africa
| | - Leszek Lisowski
- Translational Vectorology Unit, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW, Australia
- Military Institute of Medicine, Laboratory of Molecular Oncology and Innovative Therapies, Warsaw, Poland
| | - Ian E. Alexander
- Gene Therapy Research Unit, Children’s Medical Research Institute and Children’s Hospital at Westmead, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
- Discipline of Child and Adolescent Health, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - Paul Gissen
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- National Institute of Health Research, Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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12
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Couchet M, Breuillard C, Corne C, Rendu J, Morio B, Schlattner U, Moinard C. Ornithine Transcarbamylase - From Structure to Metabolism: An Update. Front Physiol 2021; 12:748249. [PMID: 34658931 PMCID: PMC8517447 DOI: 10.3389/fphys.2021.748249] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/07/2021] [Indexed: 12/30/2022] Open
Abstract
Ornithine transcarbamylase (OTC; EC 2.1.3.3) is a ubiquitous enzyme found in almost all organisms, including vertebrates, microorganisms, and plants. Anabolic, mostly trimeric OTCs catalyze the production of L-citrulline from L-ornithine which is a part of the urea cycle. In eukaryotes, such OTC localizes to the mitochondrial matrix, partially bound to the mitochondrial inner membrane and part of channeling multi-enzyme assemblies. In mammals, mainly two organs express OTC: the liver, where it is an integral part of the urea cycle, and the intestine, where it synthesizes citrulline for export and plays a major role in amino acid homeostasis, particularly of L-glutamine and L-arginine. Here, we give an overview on OTC genes and proteins, their tissue distribution, regulation, and physiological function, emphasizing the importance of OTC and urea cycle enzymes for metabolic regulation in human health and disease. Finally, we summarize the current knowledge of OTC deficiency, a rare X-linked human genetic disorder, and its emerging role in various chronic pathologies.
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Affiliation(s)
- Morgane Couchet
- Université Grenoble Alpes, Inserm U1055, Laboratory of Fundamental and Applied Bioenergetics, Grenoble, France
| | - Charlotte Breuillard
- Université Grenoble Alpes, Inserm U1055, Laboratory of Fundamental and Applied Bioenergetics, Grenoble, France
| | | | - John Rendu
- Centre Hospitalier Université Grenoble Alpes, Grenoble, France
| | - Béatrice Morio
- CarMeN Laboratory, INSERM U1060, INRAE U1397, Lyon, France
| | - Uwe Schlattner
- Université Grenoble Alpes, Inserm U1055, Laboratory of Fundamental and Applied Bioenergetics, Grenoble, France.,Institut Universitaire de France, Paris, France
| | - Christophe Moinard
- Université Grenoble Alpes, Inserm U1055, Laboratory of Fundamental and Applied Bioenergetics, Grenoble, France
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13
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Ribas GS, Lopes FF, Deon M, Vargas CR. Hyperammonemia in Inherited Metabolic Diseases. Cell Mol Neurobiol 2021; 42:2593-2610. [PMID: 34665389 DOI: 10.1007/s10571-021-01156-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/10/2021] [Indexed: 12/13/2022]
Abstract
Ammonia is a neurotoxic compound which is detoxified through liver enzymes from urea cycle. Several inherited or acquired conditions can elevate ammonia concentrations in blood, causing severe damage to the central nervous system due to the toxic effects exerted by ammonia on the astrocytes. Therefore, hyperammonemic patients present potentially life-threatening neuropsychiatric symptoms, whose severity is related with the hyperammonemia magnitude and duration, as well as the brain maturation stage. Inherited metabolic diseases caused by enzymatic defects that compromise directly or indirectly the urea cycle activity are the main cause of hyperammonemia in the neonatal period. These diseases are mainly represented by the congenital defects of urea cycle, classical organic acidurias, and the defects of mitochondrial fatty acids oxidation, with hyperammonemia being more severe and frequent in the first two groups mentioned. An effective and rapid treatment of hyperammonemia is crucial to prevent irreversible neurological damage and it depends on the understanding of the pathophysiology of the diseases, as well as of the available therapeutic approaches. In this review, the mechanisms underlying the hyperammonemia and neurological dysfunction in urea cycle disorders, organic acidurias, and fatty acids oxidation defects, as well as the therapeutic strategies for the ammonia control will be discussed.
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Affiliation(s)
- Graziela Schmitt Ribas
- Departamento de Análises Clínicas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Serviço de Genética Médica, Hospital de Clíınicas de Porto Alegre, Ramiro Barcelos, 2350, Porto Alegre, RS, CEP 90035-003, Brazil.
| | - Franciele Fátima Lopes
- Serviço de Genética Médica, Hospital de Clíınicas de Porto Alegre, Ramiro Barcelos, 2350, Porto Alegre, RS, CEP 90035-003, Brazil
| | - Marion Deon
- Serviço de Genética Médica, Hospital de Clíınicas de Porto Alegre, Ramiro Barcelos, 2350, Porto Alegre, RS, CEP 90035-003, Brazil
| | - Carmen Regla Vargas
- Departamento de Análises Clínicas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Serviço de Genética Médica, Hospital de Clíınicas de Porto Alegre, Ramiro Barcelos, 2350, Porto Alegre, RS, CEP 90035-003, Brazil.
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14
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Kido J, Matsumoto S, Takeshita E, Hayasaka C, Yamada K, Kagawa J, Nakajima Y, Ito T, Iijima H, Endo F, Nakamura K. Current status of surviving patients with arginase 1 deficiency in Japan. Mol Genet Metab Rep 2021; 29:100805. [PMID: 34646736 PMCID: PMC8495172 DOI: 10.1016/j.ymgmr.2021.100805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/14/2022] Open
Abstract
Arginase 1 (ARG1) deficiency is a rare urea cycle disorder (UCD), with an estimated frequency of 1 per 2,200,000 births in Japan. Patients with ARG1 deficiency develop symptoms in late infancy or pre-school age with progressive neurological manifestations and sometimes present with severe hepatic disease. We previously investigated the status of UCDs in Japan; however, only one patient was identified as having ARG1 deficiency. Therefore, we aimed to investigate the current status of patients with ARG1 deficiency in 2018–2021 because almost 10 years have passed since the previous study. We present the disease history, clinical outcome, and treatment of five surviving patients with ARG1 deficiency and discuss the features of ARG1 deficiency in Japan. We found that clinicians often face difficulty in diagnosing ARG1 deficiency at the early stage of onset because of interpatient variability in onset time and clinical manifestations. Blood L-arginine and guanidino compounds were considered to be the major factors causing adverse neurodevelopmental outcomes. Therefore, early detection and intervention of ARG1 deficiency is essential for improved neurodevelopmental outcomes. Liver transplantation has been considered an effective treatment option that can dramatically improve the quality of life of patients, prior to the neurological manifestation of symptoms caused by ARG1 deficiency.
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Affiliation(s)
- Jun Kido
- Department of Pediatrics, Faculty of Life Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan
| | - Shirou Matsumoto
- Department of Pediatrics, Faculty of Life Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan
| | - Eiko Takeshita
- Department of Pediatrics, Yanagawa Institute for Developmental Disabilities, International University of Health and Welfare, Yanagawa City, Fukuoka, Japan
| | | | - Keitaro Yamada
- Department of Pediatric Neurology, Aichi Developmental Disability Center Central Hospital, Kasugai City, Aichi, Japan
| | - Jiro Kagawa
- Department of Pediatrics, Fujieda Municipal General Hospital, Fujieda City, Shizuoka, Japan
| | - Yoko Nakajima
- Department of Pediatrics, Fujita Health University School of Medicine, Toyoake City, Aichi, Japan
| | - Tetsuya Ito
- Department of Pediatrics, Fujita Health University School of Medicine, Toyoake City, Aichi, Japan
| | - Hiroyuki Iijima
- Department of General Pediatrics & Interdisciplinary Medicine, National Center for Child Health and Development, Tokyo, Japan
| | - Fumio Endo
- Department of Pediatrics, Faculty of Life Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan
| | - Kimitoshi Nakamura
- Department of Pediatrics, Faculty of Life Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan
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15
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De Bruyne P, Verloo P, Van Hove JLK, de Hemptinne B, Vande Velde S, Van Winckel M, Van Biervliet S, De Bruyne R. Successful liver transplantation in hyperornithinemia-hyperammonemia-homocitrullinuria syndrome: Case report. Pediatr Transplant 2021; 25:e13943. [PMID: 33314525 DOI: 10.1111/petr.13943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND HHH syndrome is a rare autosomal recessive disorder of the urea cycle, caused by a deficient mitochondrial ornithine transporter. We report the first successful liver transplantation in HHH syndrome performed in a seven-year-old boy. The patient presented at 4 weeks of age with hyperammonemic coma. The plasma amino acid profile was suggestive of HHH syndrome, and the diagnosis was confirmed when sequencing of the SLC25A15 gene identified two mutations p.R275Q and p.A76D. Although immediate intervention resulted in normalization of plasma ammonia levels within 24 hours, he developed cerebral edema, coma, convulsions, and subsequent neurological sequelae. Metabolic control was difficult requiring severe protein restriction and continued treatment with sodium benzoate and L-arginine. Despite substantial developmental delay, he was referred to our center for liver transplantation because of poor metabolic control. Following cadaveric split liver transplantation, there was complete normalization of his plasma ammonia and plasma amino acid levels under a normal protein-containing diet. This excellent metabolic control was associated with a markedly improved general condition, mood and behavior, and small developmental achievements. Twelve years after liver transplantation, the patient has a stable cognitive impairment without progression of spastic diplegia. CONCLUSION This first case of liver transplantation in HHH syndrome demonstrates that this procedure is a therapeutic option for HHH patients with difficult metabolic control.
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Affiliation(s)
- Pauline De Bruyne
- Department of Internal Medicine and Genetics, Ghent University, Ghent, Belgium
| | - Patrick Verloo
- Department of Pediatric Neurology, Princess Elisabeth Children's Hospital, Ghent University Hospital, Ghent, Belgium
| | - Johan L K Van Hove
- Department of Pediatrics, University Hospital Gasthuisberg, University of Leuven, Leuven, Belgium
| | - Bernard de Hemptinne
- Department of General, Hepatobiliary and Liver Transplantation Surgery, Ghent University Hospital, Ghent, Belgium
| | - Saskia Vande Velde
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Princess Elisabeth Children's Hospital, Ghent University Hospital, Ghent, Belgium
| | - Myriam Van Winckel
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Princess Elisabeth Children's Hospital, Ghent University Hospital, Ghent, Belgium
| | - Stephanie Van Biervliet
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Princess Elisabeth Children's Hospital, Ghent University Hospital, Ghent, Belgium
| | - Ruth De Bruyne
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Princess Elisabeth Children's Hospital, Ghent University Hospital, Ghent, Belgium
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16
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Menon J, Vij M, Sachan D, Rammohan A, Shanmugam N, Kaliamoorthy I, Rela M. Pediatric metabolic liver diseases: Evolving role of liver transplantation. World J Transplant 2021; 11:161-179. [PMID: 34164292 PMCID: PMC8218348 DOI: 10.5500/wjt.v11.i6.161] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 05/13/2021] [Accepted: 06/03/2021] [Indexed: 02/06/2023] Open
Abstract
Metabolic liver diseases (MLD) are the second most common indication for liver transplantation (LT) in children. This is based on the fact that the majority of enzymes involved in various metabolic pathways are present within the liver and LT can cure or at least control the disease manifestation. LT is also performed in metabolic disorders for end-stage liver disease, its sequelae including hepatocellular cancer. It is also performed for preventing metabolic crisis’, arresting progression of neurological dysfunction with a potential to reverse symptoms in some cases and for preventing damage to end organs like kidneys as in the case of primary hyperoxalosis and methyl malonic acidemia. Pathological findings in explant liver with patients with metabolic disease include unremarkable liver to steatosis, cholestasis, inflammation, variable amount of fibrosis, and cirrhosis. The outcome of LT in metabolic disorders is excellent except for patients with mitochondrial disorders where significant extrahepatic involvement leads to poor outcomes and hence considered a contraindication for LT. A major advantage of LT is that in the post-operative period most patients can discontinue the special formula which they were having prior to the transplant and this increases their well-being and improves growth parameters. Auxiliary partial orthotopic LT has been described for patients with noncirrhotic MLD where a segmental graft is implanted in an orthotopic position after partial resection of the native liver. The retained native liver can be the potential target for future gene therapy when it becomes a clinical reality.
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Affiliation(s)
- Jagadeesh Menon
- Institute of Liver Disease and Transplantation, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Mukul Vij
- Department of Pathology, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Deepti Sachan
- Department of Transfusion Medicine, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Ashwin Rammohan
- Institute of Liver Disease and Transplantation, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Naresh Shanmugam
- Institute of Liver Disease and Transplantation, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Ilankumaran Kaliamoorthy
- Institute of Liver Disease and Transplantation, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
| | - Mohamed Rela
- Institute of Liver Disease and Transplantation, Dr Rela Institute and Medical Center, Chennai 600044, Tamil Nadu, India
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17
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Nitzahn M, Lipshutz GS. CPS1: Looking at an ancient enzyme in a modern light. Mol Genet Metab 2020; 131:289-298. [PMID: 33317798 PMCID: PMC7738762 DOI: 10.1016/j.ymgme.2020.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/02/2020] [Accepted: 10/03/2020] [Indexed: 02/06/2023]
Abstract
The mammalian urea cycle (UC) is responsible for siphoning catabolic waste nitrogen into urea for excretion. Disruptions of the functions of any of the enzymes or transporters lead to elevated ammonia and neurological injury. Carbamoyl phosphate synthetase 1 (CPS1) is the first and rate-limiting UC enzyme responsible for the direct incorporation of ammonia into UC intermediates. Symptoms in CPS1 deficiency are typically the most severe of all UC disorders, and current clinical management is insufficient to prevent the associated morbidities and high mortality. With recent advances in basic and translational studies of CPS1, appreciation for this enzyme's essential role in the UC has been broadened to include systemic metabolic regulation during homeostasis and disease. Here, we review recent advances in CPS1 biology and contextualize them around the role of CPS1 in health and disease.
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Affiliation(s)
- Matthew Nitzahn
- Molecular Biology Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Gerald S Lipshutz
- Molecular Biology Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Psychiatry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Intellectual and Developmental Disabilities Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Semel Institute for Neuroscience, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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18
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Schiergens KA, Weiß KJ, Dokoupil K, Fleissner S, Maier EM. [Dietary treatment of inborn errors of metabolism-a balancing act between indulgence and therapy]. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2020; 63:864-871. [PMID: 32542434 DOI: 10.1007/s00103-020-03168-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
For many inborn metabolic diseases, a lifelong diet is a crucial part of the therapy since pharmacological therapy is available for only a few conditions and patients. The implementation of a low natural protein diet with a reduced intake of natural protein and the complementary use of synthetic amino acid mixtures is described using the examples of phenylketonuria and urea cycle disorders focusing on children and adolescents. For phenylketonuria, the amino acid supplement is free of phenylalanine whereas for urea cycle disorders, it exclusively consists of essential amino acids. The dietary treatment aims to maintain metabolic stability and to prevent accumulation of toxic metabolites. At the same time, the nutritional requirements to ensure growth and development must be met. Therefore, patients need to follow strict rules regarding the choice of food products. This restrictive therapy interferes with the desire for autonomy and the joy of eating and often results in a reduced quality of life.Following the diet is crucial for a favorable outcome. To meet its requirements, patients and their families are provided with training. It is a great challenge not only to support the patients and their families in all practical aspects of dietary management, but also to motivate them to lifelong adherence in order to ensure the best possible outcome.
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Affiliation(s)
- Katharina A Schiergens
- Abteilung für angeborene Stoffwechselerkrankungen, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital der LMU München, Lindwurmstr. 4, 80337, München, Deutschland
| | - Katharina J Weiß
- Abteilung für angeborene Stoffwechselerkrankungen, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital der LMU München, Lindwurmstr. 4, 80337, München, Deutschland
| | - Katharina Dokoupil
- Abteilung für angeborene Stoffwechselerkrankungen, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital der LMU München, Lindwurmstr. 4, 80337, München, Deutschland
| | - Sandra Fleissner
- Abteilung für angeborene Stoffwechselerkrankungen, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital der LMU München, Lindwurmstr. 4, 80337, München, Deutschland
| | - Esther M Maier
- Abteilung für angeborene Stoffwechselerkrankungen, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital der LMU München, Lindwurmstr. 4, 80337, München, Deutschland.
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19
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Jain-Ghai S, Joffe AR, Bond GY, Siriwardena K, Chan A, Yap JYK, Hajihosseini M, Dinu IA, Acton BV, Robertson CMT. Pre-school neurocognitive and functional outcomes after liver transplant in children with early onset urea cycle disorders, maple syrup urine disease, and propionic acidemia: An inception cohort matched-comparison study. JIMD Rep 2020; 52:43-54. [PMID: 32154059 PMCID: PMC7052695 DOI: 10.1002/jmd2.12095] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 12/20/2019] [Accepted: 01/07/2020] [Indexed: 12/23/2022] Open
Abstract
Background Urea cycle disorders (UCD) and organic acid disorders classically present in the neonatal period. In those who survive, developmental delay is common with continued risk of regression. Liver transplantation improves the biochemical abnormality and patient survival is good. We report the neurocognitive and functional outcomes post‐transplant for nine UCD, three maple syrup urine disease, and one propionic acidemia patient. Methods Thirteen inborn errors of metabolism (IEM) patients were individually one‐to‐two matched to 26 non‐IEM patients. All patients received liver transplant. Wilcoxon rank sum test was used to compare full‐scale intelligence‐quotient (FSIQ) and Adaptive Behavior Assessment System‐II General Adaptive Composite (GAC) at age 4.5 years. Dichotomous outcomes were reported as percentages. Results FSIQ and GAC median [IQR] was 75 [54, 82.5] and 62.0 [47.5, 83] in IEM compared with 94.5 [79.8, 103.5] and 88.0 [74.3, 97.5] in matched patients (P‐value <.001), respectively. Of IEM patients, 6 (46%) had intellectual disability (FSIQ and GAC <70), 5 (39%) had autism spectrum disorder, and 1/13 (8%) had cerebral palsy, compared to 1/26 (4%), 0, 0, and 0% of matched patients, respectively. In the subgroup of nine with UCDs, FSIQ (64[54, 79]), and GAC (56[45, 75]) were lower than matched patients (100.5 [98.5, 101] and 95 [86.5, 99.5]), P = .005 and .003, respectively. Conclusion This study evaluated FSIQ and GAC at age 4.5 years through a case‐comparison between IEM and matched non‐IEM patients post‐liver transplantation. The neurocognitive and functional outcomes remained poor in IEM patients, particularly in UCD. This information should be included when counselling parents regarding post‐transplant outcome.
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Affiliation(s)
- Shailly Jain-Ghai
- Department of Medical Genetics University of Alberta Edmonton Alberta Canada
| | - Ari R Joffe
- Department of Pediatrics University of Alberta Edmonton Alberta Canada
| | - Gwen Y Bond
- Department of Pediatrics Glenrose Rehabilitation Hospital Edmonton Alberta Canada
| | - Komudi Siriwardena
- Department of Medical Genetics University of Alberta Edmonton Alberta Canada
| | - Alicia Chan
- Department of Medical Genetics University of Alberta Edmonton Alberta Canada
| | - Jason Y K Yap
- University of Melbourne The Royal Children's Hospital Melbourne Australia
| | - Morteza Hajihosseini
- School of Public Health (Biostatistics) University of Alberta Edmonton Alberta Canada
| | - Irina A Dinu
- School of Public Health (Biostatistics) University of Alberta Edmonton Alberta Canada
| | - Bryan V Acton
- Department of Psychology University of Saskatchewan Saskatoon Saskatchewan Canada
| | - Charlene M T Robertson
- Department of Pediatrics University of Alberta Edmonton Alberta Canada.,Department of Pediatrics Glenrose Rehabilitation Hospital Edmonton Alberta Canada
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20
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Soria LR, Nitzahn M, Angelis AD, Khoja S, Attanasio S, Annunziata P, Palmer DJ, Ng P, Lipshutz GS, Brunetti-Pierri N. Hepatic glutamine synthetase augmentation enhances ammonia detoxification. J Inherit Metab Dis 2019; 42:1128-1135. [PMID: 30724386 PMCID: PMC6684872 DOI: 10.1002/jimd.12070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 01/28/2019] [Indexed: 12/18/2022]
Abstract
The urea cycle and glutamine synthetase (GS) are the two main pathways for waste nitrogen removal and their deficiency results in hyperammonemia. Here, we investigated the efficacy of liver-specific GS overexpression for therapy of hyperammonemia. To achieve hepatic GS overexpression, we generated a helper-dependent adenoviral (HDAd) vector expressing the murine GS under the control of a liver-specific expression cassette (HDAd-GS). Compared to mice injected with a control vector expressing an unrelated reporter gene (HDAd-alpha-fetoprotein), wild-type mice with increased hepatic GS showed reduced blood ammonia levels and a concomitant increase of blood glutamine after intraperitoneal injections of ammonium chloride, whereas blood urea was unaffected. Moreover, injection of HDAd-GS reduced blood ammonia levels at baseline and protected against acute hyperammonemia following ammonia challenge in a mouse model with conditional hepatic deficiency of carbamoyl phosphate synthetase 1 (Cps1), the initial and rate-limiting step of ureagenesis. In summary, we found that upregulation of hepatic GS reduced hyperammonemia in wild-type and Cps1-deficient mice, thus confirming a key role of GS in ammonia detoxification. These results suggest that hepatic GS augmentation therapy has potential for treatment of both primary and secondary forms of hyperammonemia.
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Affiliation(s)
| | - Matthew Nitzahn
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, United States
- Molecular Biology Institute at UCLA, Los Angeles, United States
| | | | - Suhail Khoja
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, United States
- Molecular Biology Institute at UCLA, Los Angeles, United States
| | | | | | - Donna J. Palmer
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
| | - Philip Ng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
| | - Gerald S. Lipshutz
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, United States
- Molecular Biology Institute at UCLA, Los Angeles, United States
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
- Department of Translational Medicine, Federico II University, Naples, Italy
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21
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Häberle J, Burlina A, Chakrapani A, Dixon M, Karall D, Lindner M, Mandel H, Martinelli D, Pintos-Morell G, Santer R, Skouma A, Servais A, Tal G, Rubio V, Huemer M, Dionisi-Vici C. Suggested guidelines for the diagnosis and management of urea cycle disorders: First revision. J Inherit Metab Dis 2019; 42:1192-1230. [PMID: 30982989 DOI: 10.1002/jimd.12100] [Citation(s) in RCA: 249] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 04/04/2019] [Accepted: 04/08/2019] [Indexed: 02/06/2023]
Abstract
In 2012, we published guidelines summarizing and evaluating late 2011 evidence for diagnosis and therapy of urea cycle disorders (UCDs). With 1:35 000 estimated incidence, UCDs cause hyperammonemia of neonatal (~50%) or late onset that can lead to intellectual disability or death, even while effective therapies do exist. In the 7 years that have elapsed since the first guideline was published, abundant novel information has accumulated, experience on newborn screening for some UCDs has widened, a novel hyperammonemia-causing genetic disorder has been reported, glycerol phenylbutyrate has been introduced as a treatment, and novel promising therapeutic avenues (including gene therapy) have been opened. Several factors including the impact of the first edition of these guidelines (frequently read and quoted) may have increased awareness among health professionals and patient families. However, under-recognition and delayed diagnosis of UCDs still appear widespread. It was therefore necessary to revise the original guidelines to ensure an up-to-date frame of reference for professionals and patients as well as for awareness campaigns. This was accomplished by keeping the original spirit of providing a trans-European consensus based on robust evidence (scored with GRADE methodology), involving professionals on UCDs from nine countries in preparing this consensus. We believe this revised guideline, which has been reviewed by several societies that are involved in the management of UCDs, will have a positive impact on the outcomes of patients by establishing common standards, and spreading and harmonizing good practices. It may also promote the identification of knowledge voids to be filled by future research.
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Affiliation(s)
- Johannes Häberle
- University Children's Hospital Zurich and Children's Research Centre, Zurich, Switzerland
| | - Alberto Burlina
- Division of Inborn Metabolic Disease, Department of Pediatrics, University Hospital Padua, Padova, Italy
| | - Anupam Chakrapani
- Department of Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Marjorie Dixon
- Dietetics, Great Ormond Street Hospital for Children, NHS Trust, London, UK
| | - Daniela Karall
- Clinic for Pediatrics, Division of Inherited Metabolic Disorders, Medical University of Innsbruck, Innsbruck, Austria
| | - Martin Lindner
- University Children's Hospital, Frankfurt am Main, Germany
| | - Hanna Mandel
- Institute of Human Genetics and metabolic disorders, Western Galilee Medical Center, Nahariya, Israel
| | - Diego Martinelli
- Division of Metabolism, Bambino Gesù Children's Hospital, Rome, Italy
| | - Guillem Pintos-Morell
- Centre for Rare Diseases, University Hospital Vall d'Hebron, Barcelona, Spain
- CIBERER_GCV08, Research Institute IGTP, Barcelona, Spain
- Universitat Autònoma de Barcelona, Barcelona, Spain
| | - René Santer
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anastasia Skouma
- Institute of Child Health, Agia Sofia Children's Hospital, Athens, Greece
| | - Aude Servais
- Service de Néphrologie et maladies métaboliques adulte Hôpital Necker 149, Paris, France
| | - Galit Tal
- The Ruth Rappaport Children's Hospital, Rambam Medical Center, Haifa, Israel
| | - Vicente Rubio
- Instituto de Biomedicina de Valencia (IBV-CSIC), Centro de Investigación Biomédica en Red para Enfermedades Raras (CIBERER), Valencia, Spain
| | - Martina Huemer
- University Children's Hospital Zurich and Children's Research Centre, Zurich, Switzerland
- Department of Paediatrics, Landeskrankenhaus Bregenz, Bregenz, Austria
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22
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Srinivasan RC, Zabulica M, Hammarstedt C, Wu T, Gramignoli R, Kannisto K, Ellis E, Karadagi A, Fingerhut R, Allegri G, Rüfenacht V, Thöny B, Häberle J, Nuoffer JM, Strom SC. A liver-humanized mouse model of carbamoyl phosphate synthetase 1-deficiency. J Inherit Metab Dis 2019; 42:1054-1063. [PMID: 30843237 DOI: 10.1002/jimd.12067] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/25/2019] [Indexed: 12/31/2022]
Abstract
A liver-humanized mouse model for CPS1-deficiency was generated by the high-level repopulation of the mouse liver with CPS1-deficient human hepatocytes. When compared with mice that are highly repopulated with CPS1-proficient human hepatocytes, mice that are repopulated with CPS1-deficient human hepatocytes exhibited characteristic symptoms of human CPS1 deficiency including an 80% reduction in CPS1 metabolic activity, delayed clearance of an ammonium chloride infusion, elevated glutamine and glutamate levels, and impaired metabolism of [15 N]ammonium chloride into urea, with no other obvious phenotypic differences. Because most metabolic liver diseases result from mutations that alter critical pathways in hepatocytes, a model that incorporates actual disease-affected, mutant human hepatocytes is useful for the investigation of the molecular, biochemical, and phenotypic differences induced by that mutation. The model is also expected to be useful for investigations of modified RNA, gene, and cellular and small molecule therapies for CPS1-deficiency. Liver-humanized models for this and other monogenic liver diseases afford the ability to assess the therapy on actual disease-affected human hepatocytes, in vivo, for long periods of time and will provide data that are highly relevant for investigations of the safety and efficacy of gene-editing technologies directed to human hepatocytes and the translation of gene-editing technology to the clinic.
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Affiliation(s)
- Raghuraman C Srinivasan
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Mihaela Zabulica
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Christina Hammarstedt
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Tingting Wu
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Roberto Gramignoli
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Kristina Kannisto
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Stockholm, Sweden
| | - Ewa Ellis
- Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
| | - Ahmad Karadagi
- Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
| | - Ralph Fingerhut
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
- Swiss Newborn Screening Laboratory, University Children's Hospital Zurich, Zurich, Switzerland
| | - Gabriella Allegri
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
| | - Véronique Rüfenacht
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
| | - Beat Thöny
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
- Swiss Newborn Screening Laboratory, University Children's Hospital Zurich, Zurich, Switzerland
| | - Johannes Häberle
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) and, Neuroscience Centre Zurich (ZNZ), Zurich, Switzerland
| | - Jean-Marc Nuoffer
- Institute for Clinical Chemistry and University Children's Hospital, Bern, Switzerland
| | - Stephen C Strom
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden
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23
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Urea cycle disorders-update. J Hum Genet 2019; 64:833-847. [PMID: 31110235 DOI: 10.1038/s10038-019-0614-4] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 04/14/2019] [Accepted: 04/15/2019] [Indexed: 12/14/2022]
Abstract
The urea cycle is a metabolic pathway for the disposal of excess nitrogen, which arises primarily as ammonia. Nitrogen is essential for growth and life-maintenance, but excessive ammonia leads to life-threatening conditions. The urea cycle disorders (UCDs) comprise diseases presenting with hyperammonemia that arise in either the neonatal period (about 50% of cases) or later. Congenital defects of the enzymes or transporters of the urea cycle cause the disease. This cycle utilizes five enzymes, two of which, carbamoylphosphate synthetase 1 and ornithine transcarbamylase are present in the mitochondrial matrix, whereas the others (argininosuccinate synthetase, argininosuccinate lyase and arginase 1) are present in the cytoplasm. In addition, N-acetylglutamate synthase and at least two transporter proteins are essential to urea cycle function. Severity and age of onset depend on residual enzyme or transporter function and are related to the respective gene mutations. The strategy for therapy is to prevent the irreversible toxicity of high-ammonia exposure to the brain. The pathogenesis and natural course are poorly understood because of the rarity of the disease, so an international registry system and novel clinical trials are much needed. We review here the current concepts of the pathogenesis, diagnostics, including genetics and treatment of UCDs.
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24
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Ashley SN, Nordin JML, Buza EL, Greig JA, Wilson JM. Adeno-associated viral gene therapy corrects a mouse model of argininosuccinic aciduria. Mol Genet Metab 2018; 125:241-250. [PMID: 30253962 DOI: 10.1016/j.ymgme.2018.08.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 08/26/2018] [Accepted: 08/27/2018] [Indexed: 12/11/2022]
Abstract
Argininosuccinic aciduria (ASA) is the second most common genetic disorder affecting the urea cycle. The disease is caused by deleterious mutations in the gene encoding argininosuccinate lyase (ASL); total loss of ASL activity results in severe neonatal onset of the disease, which is characterized by hyperammonemia within a few days of birth that can rapidly progress to coma and death. The long-term complications of ASA, such as hypertension and neurocognitive deficits, appear to be resistant to the current treatment options of dietary restriction, arginine supplementation, and nitrogen scavenging drugs. Treatment-resistant disease is currently being managed by orthotopic liver transplant, which shows variable improvement and requires lifetime immunosuppression. Here, we developed a gene therapy strategy for ASA aimed at alleviating the symptoms associated with urea cycle disruption by providing stable expression of ASL protein in the liver. We designed a codon-optimized human ASL gene packaged within adeno-associated virus serotype 8 (AAV8) as a vector for targeted delivery to the liver. To evaluate the therapeutic efficacy of this approach, we utilized a murine hypomorphic model of ASA. Neonatal administration of AAV8 via the temporal facial vein extended survival in ASA hypomorphic mice, although not to wild-type levels. Intravenous injection into adolescent hypomorphic mice led to increased survival and body weight and correction of metabolites associated with the disease. Our results demonstrate that AAV8 gene therapy is a viable approach for the treatment of ASA.
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Affiliation(s)
- Scott N Ashley
- Gene Therapy Program, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jayme M L Nordin
- Gene Therapy Program, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Elizabeth L Buza
- Gene Therapy Program, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jenny A Greig
- Gene Therapy Program, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - James M Wilson
- Gene Therapy Program, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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25
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Meyburg J, Opladen T, Spiekerkötter U, Schlune A, Schenk JP, Schmidt J, Weitz J, Okun J, Bürger F, Omran TB, Abdoh G, Al Rifai H, Monavari A, Konstantopoulou V, Kölker S, Yudkoff M, Hoffmann GF. Human heterologous liver cells transiently improve hyperammonemia and ureagenesis in individuals with severe urea cycle disorders. J Inherit Metab Dis 2018; 41:81-90. [PMID: 29027067 DOI: 10.1007/s10545-017-0097-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/19/2017] [Accepted: 09/22/2017] [Indexed: 12/16/2022]
Abstract
BACKGROUND Urea cycle disorders (UCDs) still have a poor prognosis despite several therapeutic advancements. As liver transplantation can provide a cure, liver cell therapy (LCT) might be a new therapeutic option in these patients. METHODS Twelve patients with severe UCDs were included in this prospective clinical trial. Patients received up to six infusions of cryopreserved human heterologous liver cells via a surgically placed catheter in the portal vein. Portal vein pressure, portal vein flow, and vital signs were monitored continuously. Calcineurin inhibitors and steroids were used for immunosuppression. In four patients, ureagenesis was determined with stable isotopes. Number and severity of hyperammonemic events and side effects of immunosuppression were analyzed during an observation period of up to 2 years. RESULTS No study-related mortality was observed. The application catheter dislocated in two children. No significant side effects of catheter application or cell infusion were noted in the other ten patients. The overall incidence of infections did not differ significantly from a historical control group, and no specific side effects of immunosuppression were found. Seven patients were treated per protocol and could be analyzed for efficacy. Severe metabolic crises could be prevented in all of these patients, moderate crises in four of seven. Ureagenesis increased after cell infusion in all patients investigated. CONCLUSIONS We found a favorable safety profile with respect to catheter placement, intraportal liver cell infusion, and immunosuppression. More than half of the children treated per protocol experienced metabolic stabilization and could be safely bridged to liver transplantation.
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Affiliation(s)
- Jochen Meyburg
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany.
| | - Thomas Opladen
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany
| | - Ute Spiekerkötter
- Department of General Pediatrics, Neonatology and Paediatric Cardiology, Medical Faculty, Heinrich-Heine-University, Duesseldorf, Germany
- Division of General Pediatrics, University Children's Hospital, Freiburg, Germany
| | - Andrea Schlune
- Department of General Pediatrics, Neonatology and Paediatric Cardiology, Medical Faculty, Heinrich-Heine-University, Duesseldorf, Germany
| | - Jens-Peter Schenk
- Division of Pediatric Radiology, Department of Diagnostic and Interventional Radiology, University Hospital, Heidelberg, Germany
| | - Jan Schmidt
- Department of Visceral and Transplant Surgery, University Hospital, Heidelberg, Germany
| | - Jürgen Weitz
- Department of Visceral and Transplant Surgery, University Hospital, Heidelberg, Germany
| | - Jürgen Okun
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany
| | - Friederike Bürger
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany
| | - Tawfeg Ben Omran
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Ghassan Abdoh
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Hilal Al Rifai
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Ahmad Monavari
- National Centre of Inherited Metabolic Disorders, Dublin, Ireland
| | - Vassiliki Konstantopoulou
- Division of Pulmonology, Allergology, Endocrinology, and Metabolic Medicine, University Children's Hospital, Vienna, Austria
| | - Stefan Kölker
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany
| | - Marc Yudkoff
- Division of Metabolic Diseases, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Georg F Hoffmann
- Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Im Neuenheimer Feld 430, D-69120, Heidelberg, Germany
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26
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Tarasenko TN, McGuire PJ. The liver is a metabolic and immunologic organ: A reconsideration of metabolic decompensation due to infection in inborn errors of metabolism (IEM). Mol Genet Metab 2017; 121:283-288. [PMID: 28666653 PMCID: PMC5553615 DOI: 10.1016/j.ymgme.2017.06.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 06/22/2017] [Accepted: 06/23/2017] [Indexed: 12/30/2022]
Abstract
Metabolic decompensation in inborn errors of metabolism (IEM) is characterized by a rapid deterioration in metabolic status leading to life-threatening biochemical perturbations (e.g. hypoglycemia, hyperammonemia, acidosis, organ failure). Infection is the major cause of metabolic decompensation in patients with IEM. We hypothesized that activation of the immune system during infection leads to further perturbations in end-organ metabolism resulting in increased morbidity. To address this, we established model systems of metabolic decompensation due to infection. Using these systems, we have described the pathologic mechanisms of metabolic decompensation as well as changes in hepatic metabolic reserve associated with infection. First and foremost, our studies have demonstrated that the liver experiences a significant local innate immune response during influenza infection that modulates hepatic metabolism. Based on these findings, we are the first to suggest that the role of the liver as a metabolic and immunologic organ is central in the pathophysiology of metabolic decompensation due to infection in IEM. The dual function of the liver as a major metabolic regulator and a lymphoid organ responsible for immunosurveillance places this organ at risk for hepatotoxicity. Mobilization of hepatic reserve and the regenerative capacity of a healthy liver compensates for this calculated risk. However, activation of the hepatic innate immune system may be deleterious in IEM. Based on this assertion, strategies aimed at modulating the innate immune response may be a viable target for intervention in the treatment of hepatic metabolic decompensation.
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Affiliation(s)
- Tatyana N Tarasenko
- Metabolism, Infection and Immunity Section, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States
| | - Peter J McGuire
- Metabolism, Infection and Immunity Section, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States.
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27
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Diez-Fernandez C, Häberle J. Targeting CPS1 in the treatment of Carbamoyl phosphate synthetase 1 (CPS1) deficiency, a urea cycle disorder. Expert Opin Ther Targets 2017; 21:391-399. [PMID: 28281899 DOI: 10.1080/14728222.2017.1294685] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Carbamoyl phosphate synthetase 1 (CPS1) deficiency (CPS1D) is a rare autosomal recessive urea cycle disorder (UCD), which can lead to life-threatening hyperammonemia. Unless promptly treated, it can result in encephalopathy, coma and death, or intellectual disability in surviving patients. Over recent decades, therapies for CPS1D have barely improved leaving the management of these patients largely unchanged. Additionally, in many cases, current management (protein-restriction and supplementation with citrulline and/or arginine and ammonia scavengers) is insufficient for achieving metabolic stability, highlighting the importance of developing alternative therapeutic approaches. Areas covered: After describing UCDs and CPS1D, we give an overview of the structure- function of CPS1. We then describe current management and potential novel treatments including N-carbamoyl-L-glutamate (NCG), pharmacological chaperones, and gene therapy to treat hyperammonemia. Expert opinion: Probably, the first novel CPS1D therapies to reach the clinics will be the already commercial substance NCG, which is the standard treatment for N-acetylglutamate synthase deficiency and has been proven to rescue specific CPS1D mutations. Pharmacological chaperones and gene therapy are under development too, but these two technologies still have key challenges to be overcome. In addition, current experimental therapies will hopefully add further treatment options.
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Affiliation(s)
- Carmen Diez-Fernandez
- a Division of Metabolism , University Children's Hospital Zurich and Children's Research Center , Zurich , Switzerland
| | - Johannes Häberle
- a Division of Metabolism , University Children's Hospital Zurich and Children's Research Center , Zurich , Switzerland
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28
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Oishi K, Arnon R, Wasserstein MP, Diaz GA. Liver transplantation for pediatric inherited metabolic disorders: Considerations for indications, complications, and perioperative management. Pediatr Transplant 2016; 20:756-69. [PMID: 27329540 PMCID: PMC5142218 DOI: 10.1111/petr.12741] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/18/2016] [Indexed: 12/13/2022]
Abstract
LT is an effective therapeutic option for a variety of IEM. This approach can significantly improve the quality of life of patients who suffer from severe disease manifestations and/or life-threatening metabolic decompensations despite medical/dietary management. Due to the significant risks for systemic complications from surgical stressors, careful perioperative management is vital. Even after LT, some disorders require long-term dietary restriction, medical management, and monitoring of metabolites. Successful liver transplant for these complex disorders can be achieved with disease- and patient-specific strategies using a multidisciplinary approach. In this article, we review indications, complications, perioperative management, and long-term follow-up recommendations for IEM that are treatable with LT.
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Affiliation(s)
- Kimihiko Oishi
- Departments of Pediatrics, Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ronen Arnon
- Departments of Pediatrics, Pediatric Gastroenterology and Hepatology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, The Recanati / Miller Transplantation Institute, Mount Sinai Medical Center, New York, NY10029
| | - Melissa P. Wasserstein
- Departments of Pediatrics, Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - George A. Diaz
- Departments of Pediatrics, Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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29
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Yankol Y, Mecit N, Kanmaz T, Acarli K, Kalayoglu M. Argininosuccinic Aciduria-A Rare Indication for Liver Transplant: Report of Two Cases. EXP CLIN TRANSPLANT 2016; 15:581-584. [PMID: 26768012 DOI: 10.6002/ect.2015.0078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Argininosuccinic aciduria is a urea cycle disorder caused by an argininosuccinate lyase enzyme deficiency that ends with nitrogen accumulation as ammonia. Argininosuccinic aciduria patients are at risk for long-term complications including poor neurocognitive outcome, hepatic disease, and systemic hypertension despite strict pharmacologic and dietary therapy. As the liver is the principle site of activity of the urea cycle, it is logical that a liver transplant should be an option, with careful patient selection, even in the absence of cirrhosis. We present 2 pediatric argininosuccinic aciduria patients who underwent a living-donor liver transplant from their mothers. After the liver transplant, the general well-being of the patients and their quality of life improved significantly. Liver transplant should be an option for argininosuccinic aciduria patients to prevent further neurologic deterioration and improve the patient's quality of life.
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Affiliation(s)
- Yucel Yankol
- From the Memorial Sisli Hospital, Organ Transplantation Center, Istanbul, Turkey
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30
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Abstract
Human adults produce around 1000 mmol of ammonia daily. Some is reutilized in biosynthesis. The remainder is waste and neurotoxic. Eventually most is excreted in urine as urea, together with ammonia used as a buffer. In extrahepatic tissues, ammonia is incorporated into nontoxic glutamine and released into blood. Large amounts are metabolized by the kidneys and small intestine. In the intestine, this yields ammonia, which is sequestered in portal blood and transported to the liver for ureagenesis, and citrulline, which is converted to arginine by the kidneys. The amazing developments in NMR imaging and spectroscopy and molecular biology have confirmed concepts derived from early studies in animals and cell cultures. The processes involved are exquisitely tuned. When they are faulty, ammonia accumulates. Severe acute hyperammonemia causes a rapidly progressive, often fatal, encephalopathy with brain edema. Chronic milder hyperammonemia causes a neuropsychiatric illness. Survivors of severe neonatal hyperammonemia have structural brain damage. Proposed explanations for brain edema are an increase in astrocyte osmolality, generally attributed to glutamine accumulation, and cytotoxic oxidative/nitrosative damage. However, ammonia neurotoxicity is multifactorial, with disturbances also in neurotransmitters, energy production, anaplerosis, cerebral blood flow, potassium, and sodium. Around 90% of hyperammonemic patients have liver disease. Inherited defects are rare. They are being recognized increasingly in adults. Deficiencies of urea cycle enzymes, citrin, and pyruvate carboxylase demonstrate the roles of isolated pathways in ammonia metabolism. Phenylbutyrate is used routinely to treat inherited urea cycle disorders, and its use for hepatic encephalopathy is under investigation.
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Affiliation(s)
- Valerie Walker
- Department of Clinical Biochemistry, University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom.
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31
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Squires RH, Ng V, Romero R, Ekong U, Hardikar W, Emre S, Mazariegos GV. Evaluation of the pediatric patient for liver transplantation: 2014 practice guideline by the American Association for the Study of Liver Diseases, American Society of Transplantation and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition. Hepatology 2014; 60:362-98. [PMID: 24782219 DOI: 10.1002/hep.27191] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 04/22/2014] [Indexed: 12/16/2022]
Affiliation(s)
- Robert H Squires
- Department of Pediatrics, University of Pittsburgh School of Medicine; Division of Pediatric Gastroenterology, Hepatology and Nutrition, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA
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32
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Chandler RJ, Tarasenko TN, Cusmano-Ozog K, Sun Q, Sutton VR, Venditti CP, McGuire PJ. Liver-directed adeno-associated virus serotype 8 gene transfer rescues a lethal murine model of citrullinemia type 1. Gene Ther 2013; 20:1188-91. [PMID: 24131980 PMCID: PMC3855546 DOI: 10.1038/gt.2013.53] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/23/2013] [Accepted: 08/22/2013] [Indexed: 12/17/2022]
Abstract
Citrullinemia type 1 (CTLN1) is an autosomal recessive disorder of metabolism caused by a deficiency of argininosuccinate synthetase. Despite optimal management, CTLN1 patients still suffer from lethal metabolic instability and experience life threatening episodes of acute hyperammonemia. A murine model of CTLN1 (fold/fold) that displays lethality within the first 21 days of life was used to determine the efficacy of adeno-associated viral (AAV) gene transfer as a potential therapy. An AAV serotype 8 (AAV8) vector was engineered to express the human ASS1 cDNA under the control of a liver-specific promoter (thyroxine binding globulin, TBG), AAV8-TBG-hASS1, and delivered to 7–10 day old mice via intraperitoneal injection. Greater than 95% of the mice were rescued from lethality and survival was extended beyond 100 days after receiving a single dose of vector. AAV8-TBG-hASS1 treatment resulted in liver specific expression of hASS1, increased ASS1 enzyme activity, reduction in plasma ammonia and citrulline concentrations, and significant phenotypic improvement of the fold/fold growth and skin phenotypes. These experiments highlight a gene transfer approach using AAV8 vector for liver targeted gene therapy that could serve as a treatment for CTLN1.
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Affiliation(s)
- R J Chandler
- Organic Acid Research Section, Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
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33
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Shin WK, Jang YE, Lee H, Min SH, Ryu HG. Sudden severe hyperammonemia and status epilepticus -a case report-. Korean J Anesthesiol 2013; 65:262-5. [PMID: 24101963 PMCID: PMC3790040 DOI: 10.4097/kjae.2013.65.3.262] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 10/16/2012] [Accepted: 10/17/2012] [Indexed: 12/21/2022] Open
Abstract
There are various causes to a low level of consciousness in patients in the intensive care unit. Neurological injury, infection, and metabolic disarray are considered as some of the causes. A 39 year-old female patient was transferred to our hospital with septic shock due to ascending colon perforation. The patient had previously received ovarian cancer surgery and a cycle of chemotherapy at another hospital. Emergent operation for colon perforation was successful. After the operation, she was treated in the intensive care unit for infectious and pulmonary complications. She suddenly showed deterioration in her level of consciousness and had a generalized seizure. At the time of her seizure, she had severe hyperammonemia. Brain CT showed severe cerebral edema that was absent in the CT scan taken 2 days before. Continuous renal replacement therapy was conducted but was ineffective in lowering the level of serum ammonia and the patient subsequently died.
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Affiliation(s)
- Woo-Kyung Shin
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea
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34
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Fagiuoli S, Daina E, D'Antiga L, Colledan M, Remuzzi G. Monogenic diseases that can be cured by liver transplantation. J Hepatol 2013; 59:595-612. [PMID: 23578885 DOI: 10.1016/j.jhep.2013.04.004] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 04/02/2013] [Accepted: 04/02/2013] [Indexed: 02/08/2023]
Abstract
While the prevalence of most diseases caused by single-gene mutations is low and defines them as rare conditions, all together, monogenic diseases account for approximately 10 in every 1000 births according to the World Health Organisation. Orthotopic liver transplantation (LT) could offer a therapeutic option in monogenic diseases in two ways: by substituting for an injured liver or by supplying a tissue that can replace a mutant protein. In this respect, LT may be regarded as the correction of a disease at the level of the dysfunctional protein. Monogenic diseases that involve the liver represent a heterogeneous group of disorders. In conditions associated with predominant liver parenchymal damage (i.e., genetic cholestatic disorders, Wilson's disease, hereditary hemochromatosis, tyrosinemia, α1 antitrypsin deficiency), hepatic complications are the major source of morbidity and LT not only replaces a dysfunctional liver but also corrects the genetic defect and effectively cures the disease. A second group includes liver-based genetic disorders characterised by an architecturally near-normal liver (urea cycle disorders, Crigler-Najjar syndrome, familial amyloid polyneuropathy, primary hyperoxaluria type 1, atypical haemolytic uremic syndrome-1). In these defects, extrahepatic complications are the main source of morbidity and mortality while liver function is relatively preserved. Combined transplantation of other organs may be required, and other surgical techniques, such as domino and auxiliary liver transplantation, have been attempted. In a third group of monogenic diseases, the underlying genetic defect is expressed at a systemic level and liver involvement is just one of the clinical manifestations. In these conditions, LT might only be partially curative since the abnormal phenotype is maintained by extrahepatic synthesis of the toxic metabolites (i.e., methylmalonic acidemia, propionic acidemia). This review focuses on principles of diagnosis, management and LT results in both paediatric and adult populations of selected liver-based monogenic diseases, which represent examples of different transplantation strategies, driven by the understanding of the expression of the underlying genetic defect.
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Affiliation(s)
- Stefano Fagiuoli
- Gastroenterology and Transplant Hepatology, Ospedale Papa Giovanni XXIII, Bergamo, Italy.
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35
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Grünert SC, Villavicencio-Lorini P, Wermuth B, Lehnert W, Sass JO, Schwab KO. Ornithine transcarbamylase deficiency combined with type 1 diabetes mellitus - a challenge in clinical and dietary management. J Diabetes Metab Disord 2013; 12:37. [PMID: 23829977 PMCID: PMC3706312 DOI: 10.1186/2251-6581-12-37] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 07/02/2013] [Indexed: 12/30/2022]
Abstract
Ornithine transcarbamylase (OTC) deficiency is the most common urea cycle defect. The clinical presentation in female manifesting carriers varies both in onset and severity. We report on a female with insulin dependent diabetes mellitus and recurrent episodes of hyperammonemia. Since OTC activity measured in a liver biopsy sample was within normal limits, OTC deficiency was initially excluded from the differential diagnoses of hyperammonemia. Due to moderately elevated homocitrulline excretion, hyperornithinemia-hyperammonemia-homocitrullinuria-syndrome was suggested, but further assays in fibroblasts showed normal ornithine utilization. Later, when mutation analysis of the OTC gene became available, a known pathogenic missense mutation (c.533C>T) in exon 5 leading to an exchange of threonine-178 by methionine (p.Thr178Met) was detected. Skewed X-inactivation was demonstrated in leukocyte DNA. In the further clinical course the girl developed marked obesity. By initiating physical activities twice a week, therapeutic control of both diabetes and OTC deficiency improved, but obesity persisted. In conclusion, our case confirms that normal hepatic OTC enzyme activity measured in a single liver biopsy sample does not exclude a clinical relevant mosaic of OTC deficiency because of skewed X-inactivation. Mutation analysis of the OTC gene in whole blood may be a simple way to establish the diagnosis of OTC deficiency. The joint occurrence of OTC deficiency and diabetes in a patient has not been reported before.
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Affiliation(s)
- Sarah C Grünert
- Center of Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg, Germany.
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36
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McKiernan P. Liver transplantation and cell therapies for inborn errors of metabolism. J Inherit Metab Dis 2013; 36:675-80. [PMID: 23296369 DOI: 10.1007/s10545-012-9581-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 12/16/2012] [Accepted: 12/20/2012] [Indexed: 12/25/2022]
Abstract
Liver transplantation is now very successful with >85 % long term survival into adult life. When considering the impact of liver transplantation for metabolic disease two independent factors need to be considered; whether or not the defect causes liver disease and whether or not it is confined to the liver. When considering transplantation many factors need to be considered including the local success of transplantation, the impact of the metabolic disease on the patient and family and the potential for future therapeutic developments. Where transplantation is undertaken for a liver based defect there is a lifelong complete correction of the defect. Where there is a residual extrahepatic defect this will have an impact on the outcome of liver transplantation and the severity of this defect must be considered as part of the transplant assessment process. Access to a multi-disciplinary team with expertise in metabolic disease, liver disease and other relevant organ based specialists is crucial. Most children will receive transplantation from cadaveric donor but living related transplantation from a heterozygote parent is usually safe and effective. Auxiliary liver transplantation has a small but useful role where partial correction of the defect is helpful and there is a future prospect of gene therapy. The first-generation of hepatocyte transplants have shown proof of principle but to date have had a rather modest and temporary metabolic effect. Stem cells may have the potential to produce a more sustained and significant metabolic correction, but must be shown to be effective in controlled trials.
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37
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Häberle J, Boddaert N, Burlina A, Chakrapani A, Dixon M, Huemer M, Karall D, Martinelli D, Crespo PS, Santer R, Servais A, Valayannopoulos V, Lindner M, Rubio V, Dionisi-Vici C. Suggested guidelines for the diagnosis and management of urea cycle disorders. Orphanet J Rare Dis 2012; 7:32. [PMID: 22642880 PMCID: PMC3488504 DOI: 10.1186/1750-1172-7-32] [Citation(s) in RCA: 362] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 04/06/2012] [Indexed: 12/11/2022] Open
Abstract
Urea cycle disorders (UCDs) are inborn errors of ammonia detoxification/arginine synthesis due to defects affecting the catalysts of the Krebs-Henseleit cycle (five core enzymes, one activating enzyme and one mitochondrial ornithine/citrulline antiporter) with an estimated incidence of 1:8.000. Patients present with hyperammonemia either shortly after birth (~50%) or, later at any age, leading to death or to severe neurological handicap in many survivors. Despite the existence of effective therapy with alternative pathway therapy and liver transplantation, outcomes remain poor. This may be related to underrecognition and delayed diagnosis due to the nonspecific clinical presentation and insufficient awareness of health care professionals because of disease rarity. These guidelines aim at providing a trans-European consensus to: guide practitioners, set standards of care and help awareness campaigns. To achieve these goals, the guidelines were developed using a Delphi methodology, by having professionals on UCDs across seven European countries to gather all the existing evidence, score it according to the SIGN evidence level system and draw a series of statements supported by an associated level of evidence. The guidelines were revised by external specialist consultants, unrelated authorities in the field of UCDs and practicing pediatricians in training. Although the evidence degree did hardly ever exceed level C (evidence from non-analytical studies like case reports and series), it was sufficient to guide practice on both acute and chronic presentations, address diagnosis, management, monitoring, outcomes, and psychosocial and ethical issues. Also, it identified knowledge voids that must be filled by future research. We believe these guidelines will help to: harmonise practice, set common standards and spread good practices with a positive impact on the outcomes of UCD patients.
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Affiliation(s)
- Johannes Häberle
- University Children’s Hospital Zurich and Children’s Research Centre, Zurich, 8032, Switzerland
| | - Nathalie Boddaert
- Radiologie Hopital Necker, Service Radiologie Pediatrique, 149 Rue De Sevres, Paris 15, 75015, France
| | - Alberto Burlina
- Department of Pediatrics, Division of Inborn Metabolic Disease, University Hospital Padua, Via Giustiniani 3, Padova, 35128, Italy
| | - Anupam Chakrapani
- Birmingham Children’s Hospital NHS Foundation Trust, Steelhouse Lane, Birmingham, B4 6NH, United Kingdom
| | - Marjorie Dixon
- Dietetic Department, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, WC1N 3JH, United Kingdom
| | - Martina Huemer
- Kinderabteilung, LKH Bregenz, Carl-Pedenz-Strasse 2, Bregenz, A-6900, Austria
| | - Daniela Karall
- University Children’s Hospital, Medical University Innsbruck, Anichstrasse 35, Innsbruck, 6020, Austria
| | - Diego Martinelli
- Division of Metabolism, Bambino Gesù Children’s Hospital, IRCCS, Piazza S. Onofrio 4, Rome, I-00165, Italy
| | | | - René Santer
- Universitätsklinikum Hamburg Eppendorf, Klinik für Kinder- und Jugendmedizin, Martinistr. 52, Hamburg, 20246, Germany
| | - Aude Servais
- Service de Néphrologie et maladies métaboliques adulte Hôpital Necker 149, rue de Sèvres, Paris, 75015, France
| | - Vassili Valayannopoulos
- Reference Center for Inherited Metabolic Disorders (MaMEA), Hopital Necker-Enfants Malades, 149 Rue de Sevres, Paris, 75015, France
| | - Martin Lindner
- University Children’s Hospital, Im Neuenheimer Feld 430, Heidelberg, 69120, Germany
| | - Vicente Rubio
- Instituto de Biomedicina de Valencia del Consejo Superior de Investigaciones Científicas (IBV-CSIC) and Centro de Investigación Biomédica en Red para Enfermedades Raras (CIBERER), C/ Jaume Roig 11, Valencia, 46010, Spain
| | - Carlo Dionisi-Vici
- Division of Metabolism, Bambino Gesù Children’s Hospital, IRCCS, Piazza S. Onofrio 4, Rome, I-00165, Italy
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Pillai U, Kahlon R, Sondheimer J, Cadnapaphorncai P, Bhat Z. A rare case of hyperammonemia complication of high-protein parenteral nutrition. JPEN J Parenter Enteral Nutr 2012; 37:134-7. [PMID: 22610979 DOI: 10.1177/0148607112447815] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hyperammonemia is a metabolic derangement that can be potentially fatal. Primary hyperammonemia due to urea cycle enzyme deficiency is usually discovered in neonates but rarely can present in adulthood. Late-onset manifestations of urea cycle disorders can go unnoticed, until they become life threatening. The authors report a 28-year-old man who developed hyperammonemia in the hospital following parenteral nutrition (PN), leading to cerebral edema, which was fatal despite resolution of the hyperammonemia with cessation of PN and the use of continuous renal replacement therapy.
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39
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Wang L, Wang H, Morizono H, Bell P, Jones D, Lin J, McMenamin D, Yu H, Batshaw ML, Wilson JM. Sustained correction of OTC deficiency in spf( ash) mice using optimized self-complementary AAV2/8 vectors. Gene Ther 2012; 19:404-10. [PMID: 21850052 PMCID: PMC3321078 DOI: 10.1038/gt.2011.111] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 05/18/2011] [Indexed: 12/26/2022]
Abstract
Ornithine transcarbamylase deficiency (OTCD) is the most common inborn error of urea synthesis. Complete OTCD can result in hyperammonemic coma in the neonatal period, which can rapidly become fatal. Current acute therapy involves dialysis; chronic therapy involves the stimulation of alternate nitrogen clearance pathways; and the only curative approach is liver transplantation. Adeno-associated virus (AAV) vector-based gene therapy would add to current treatment options provided the vector delivers high level and stable transgene expression in liver without dose-limiting toxicity. In this study, we employed an AAV2/8-based self-complementary (sc) vector expressing the murine OTC (mOTC) gene under a liver-specific thyroxine-binding globulin promoter and examined the therapeutic effects in a mouse model of OTCD, the spf (ash) mouse. Seven days after a single intravenous injection of vector, treated mice showed complete normalization of urinary orotic acid, a measure of OTC activity. We further improved vector efficacy by incorporating a Kozak or Kozak-like sequence into mOTC complementary DNA, which increased the OTC activity by five or twofold and achieved sustained correction of orotic aciduria for up to 7 months. Our results demonstrate that vector optimizations can significantly improve the efficacy of gene therapy.
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Affiliation(s)
- Lili Wang
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Huan Wang
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Vaccine Research Institute, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Hiroki Morizono
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, District of Columbia, USA
| | - Peter Bell
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - David Jones
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, District of Columbia, USA
| | - Jianping Lin
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Deirdre McMenamin
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Hongwei Yu
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Mark L. Batshaw
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, District of Columbia, USA
| | - James M. Wilson
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine, University of Pennsylvania, Philadelphia, PA 19104
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Abstract
Ammonia is produced continuously in the body. It crosses the blood-brain barrier readily and at increased concentration it is toxic to the brain. A highly integrated system protects against this: ammonia produced during metabolism is detoxified temporarily by incorporation into the non-toxic amino acid glutamine. This is transported safely in the circulation to the small intestine, where ammonia is released, carried directly to the liver in the portal blood, converted to non-toxic urea and finally excreted in urine. As a result, plasma concentrations of ammonia in the systemic circulation are normally very low (<40 μmol/L). Hyperammonaemia develops if the urea cycle cannot control the ammonia load. This occurs when the load is excessive, portal blood from the intestines bypasses the liver and/or the urea cycle functions poorly. By far, the commonest cause is liver damage. This review focuses on other causes in adults. Because they are much less common, the diagnosis may be missed or delayed, with disastrous consequences. There is effective treatment for most of them, but it must be instituted promptly to avoid fatality or long-term neurological damage. Of particular concern are unsuspected inherited defects of the urea cycle and fatty acid oxidation presenting with catastrophic illness in previously normal individuals. Early identification of the problem is the challenge.
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Affiliation(s)
- Valerie Walker
- Department of Clinical Biochemistry, University Hospital Southampton NHS Foundation Trust, C Level MP 8, South Block, Southampton Hospital, Tremona Road, Southampton SO16 6YD, UK.
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41
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Wang L, Morizono H, Lin J, Bell P, Jones D, McMenamin D, Yu H, Batshaw ML, Wilson JM. Preclinical evaluation of a clinical candidate AAV8 vector for ornithine transcarbamylase (OTC) deficiency reveals functional enzyme from each persisting vector genome. Mol Genet Metab 2012; 105:203-11. [PMID: 22133298 PMCID: PMC3270700 DOI: 10.1016/j.ymgme.2011.10.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 10/31/2011] [Accepted: 10/31/2011] [Indexed: 10/15/2022]
Abstract
Ornithine transcarbamylase deficiency (OTCD), the most common and severe urea cycle disorder, is an excellent model for developing liver-directed gene therapy. No curative therapy exists except for liver transplantation which is limited by available donors and carries significant risk of mortality and morbidity. Adeno-associated virus 8 (AAV8) has been shown to be the most efficient vector for liver-directed gene transfer and is currently being evaluated in a clinical trial for treating hemophilia B. In this study, we generated a clinical candidate vector for a proposed OTC gene therapy trial in humans based on a self-complementary AAV8 vector expressing codon-optimized human OTC (hOTCco) under the control of a liver-specific promoter. Codon-optimization dramatically improved the efficacy of OTC gene therapy. Supraphysiological expression levels and activity of hOTC were achieved in adult spf(ash) mice following a single intravenous injection of hOTCco vector. Vector doses as low as 1×10(10) genome copies (GC) achieved robust and sustained correction of the OTCD biomarker orotic aciduria and clinical protection against an ammonia challenge. Functional expression of hOTC in 40% of liver areas was found in mice treated with a low vector dose of 1×10(9) GC. We suggest that the clinical candidate vector we have developed has the potential to achieve therapeutic effects in OTCD patients.
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Affiliation(s)
- Lili Wang
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hiroki Morizono
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, D.C., USA
| | - Jianping Lin
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Peter Bell
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David Jones
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, D.C., USA
| | - Deirdre McMenamin
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hongwei Yu
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Mark L. Batshaw
- Center for Genetic Medicine Research, Children’s National Medical Center, Children’s Research Institute, Washington, D.C., USA
| | - James M. Wilson
- Gene Therapy Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Corresponding author: Department of Pathology and Laboratory Medicine University of Pennsylvania, Philadelphia, PA 19104, USA Phone: 215-898-0226; Fax: 215-494-5444
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42
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Hyperammonemia in review: pathophysiology, diagnosis, and treatment. Pediatr Nephrol 2012; 27:207-22. [PMID: 21431427 DOI: 10.1007/s00467-011-1838-5] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 01/09/2011] [Accepted: 01/12/2011] [Indexed: 12/31/2022]
Abstract
Ammonia is an important source of nitrogen and is required for amino acid synthesis. It is also necessary for normal acid-base balance. When present in high concentrations, ammonia is toxic. Endogenous ammonia intoxication can occur when there is impaired capacity of the body to excrete nitrogenous waste, as seen with congenital enzymatic deficiencies. A variety of environmental causes and medications may also lead to ammonia toxicity. Hyperammonemia refers to a clinical condition associated with elevated ammonia levels manifested by a variety of symptoms and signs, including significant central nervous system (CNS) abnormalities. Appropriate and timely management requires a solid understanding of the fundamental pathophysiology, differential diagnosis, and treatment approaches available. The following review discusses the etiology, pathogenesis, differential diagnosis, and treatment of hyperammonemia.
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Bates TR, Lewis BD, Burnett JR, So K, Mitchell A, Delriviere L, Jeffrey GP. Late-onset carbamoyl phosphate synthetase 1 deficiency in an adult cured by liver transplantation. Liver Transpl 2011; 17:1481-4. [PMID: 21837743 DOI: 10.1002/lt.22407] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Urea cycle disorders (UCDs) are rare causes of hyperammonemic encephalopathy in adults. Most UCDs present in childhood and, if unrecognized, are rapidly fatal. Affected individuals who survive to adulthood may remain undiagnosed because of clinicians' unawareness of the condition or atypical presentations. We describe the case of a 49-year-old man who initially presented with a stroke and developed hyperammonemic encephalopathy over a period of 8 months. A diagnosis of carbamoyl phosphate synthetase type 1 deficiency was made, and the patient was referred for liver transplantation. One year after liver transplantation, the patient had normal plasma ammonia concentrations and had returned to work.
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Affiliation(s)
- Timothy R Bates
- Department of Internal Medicine, Swan District Hospital, Middle Swan, Western Australia, Australia.
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Jain-Ghai S, Nagamani SCS, Blaser S, Siriwardena K, Feigenbaum A. Arginase I deficiency: severe infantile presentation with hyperammonemia: more common than reported? Mol Genet Metab 2011; 104:107-11. [PMID: 21802329 PMCID: PMC3171515 DOI: 10.1016/j.ymgme.2011.06.025] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 06/29/2011] [Accepted: 06/29/2011] [Indexed: 11/21/2022]
Abstract
Enzyme defects of the urea cycle typically present with significant hyperammonemia and its associated toxicity, in the first few months of life. However, arginase I (ARG1) deficiency, a rare autosomal recessive disorder, has classically been the exception. ARG1 deficiency usually presents later in life with spasticity, seizures, failure to thrive and developmental regression. Neonatal and early infantile presentation of ARG1 deficiency with severe hyperammonemia remains rare and only six such cases have been described. We report a severely affected infant with ARG1 deficiency who presented at 6 weeks of age with lethargy, poor feeding and severe encephalopathy caused by hyperammonemia. The clinical and biochemical features of the proband and six other previously reported cases with neonatal or infantile-onset presentation of ARG1 deficiency with hyperammonemia are reviewed. In addition, the clinical spectrum of seven previously unpublished patients with later onset ARG1 deficiency, who also experienced recurrent hyperammonemia, is presented. Several biochemical abnormalities have been postulated to play a role in the pathogenesis of the neurological changes in ARG1 deficiency including hyperargininemia, elevated guanidino compounds and elevated glutamine levels, as well as the hyperammonemia. The index case demonstrated many of these. The cases reviewed here suggest a genotype/phenotype correlation and advocate for the addition of arginine as a primary target in newborn screening programs.
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Affiliation(s)
- Shailly Jain-Ghai
- Hospital for Sick Children, 555 University Ave, Toronto, Ontario, Canada M5G1X8.
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45
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De Bie I, Lemyre E, Lambert M. Favorable long-term outcome following severe neonatal hyperammonemic coma in a patient with argininosuccinate synthetase deficiency. JIMD Rep 2011; 1:83-8. [PMID: 23430833 DOI: 10.1007/8904_2011_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 01/24/2011] [Accepted: 01/25/2011] [Indexed: 03/24/2023] Open
Abstract
This chapter reports on the sequelae-free 8-year follow-up with normal growth, intellectual development, and schooling of a boy with argininosuccinate synthetase deficiency (citrullinemia type I) who was rescued from severe neonatal hyperammonemic coma at 8 days of life (peak ammonia level of 1,058 μmol/L). Important clinical management aspects were: rapidity of response to emergency therapeutic measures that included specific drug regimen, protein restriction, optimal caloric intake and hemodialysis, short coma duration (14 h), possible neuroprotective effect of mild systemic hypothermia during the acute episode, long-term metabolic control with strict compliance to standard of care therapeutic and dietary regimens, active prevention of subsequent hyperammonemic episodes, and early neurodevelopmental evaluations and interventions. We conclude that good long-term neurological outcome following rescue from neonatal hyperammonemic coma is rarely reported but attainable. Prospective registries and interventional studies regrouping clinical data from urea cycle disorders patients will assist clinicians in instituting the appropriate therapeutic measures to provide the best prospect of positive long-term outcome for these children.
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Affiliation(s)
- Isabelle De Bie
- Medical Genetics Division, Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, 3175 Côte Sainte-Catherine, Montréal, QC, Canada, H3T-1C5,
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46
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Induction and prevention of severe hyperammonemia in the spfash mouse model of ornithine transcarbamylase deficiency using shRNA and rAAV-mediated gene delivery. Mol Ther 2011; 19:854-9. [PMID: 21386824 DOI: 10.1038/mt.2011.32] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Urea cycle defects presenting early in life with hyperammonemia remain difficult to treat and commonly necessitate liver transplantation. Gene therapy has the potential to prevent hyperammonemic episodes while awaiting liver transplantation, and possibly also to avert the need for transplantation altogether. Ornithine transcarbamylase (OTC) deficiency, the most prevalent urea cycle disorder, provides an ideal model for the development of liver-targeted gene therapy. While we and others have successfully cured the spf(ash) mouse model of OTC deficiency using adeno-associated virus (AAV) vectors, a major limitation of this model is the presence of residual OTC enzymatic activity which confers a mild phenotype without clinically significant hyperammonemia. To better model severe disease we devised a strategy involving AAV2/8-mediated delivery of a short hairpin RNA (shRNA) to specifically knockdown residual endogenous OTC messenger RNA (mRNA). This strategy proved highly successful with vector-treated mice developing severe hyperammonemia and associated neurological impairment. Using this system, we showed that the dose of an AAV rescue construct encoding the murine OTC (mOTC) cDNA required to prevent hyperammonemia is fivefold lower than that required to control orotic aciduria. This result is favorable for clinical translation as it indicates that the threshold for therapeutic benefit is likely to be lower than indicated by earlier studies.
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47
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Clinical and biochemical characteristics of patients with urea cycle disorders in a developing country. Clin Biochem 2010; 43:461-6. [DOI: 10.1016/j.clinbiochem.2009.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/23/2009] [Accepted: 12/07/2009] [Indexed: 11/21/2022]
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Campeau PM, Pivalizza PJ, Miller G, McBride K, Karpen S, Goss J, Lee BH. Early orthotopic liver transplantation in urea cycle defects: follow up of a developmental outcome study. Mol Genet Metab 2010; 100 Suppl 1:S84-7. [PMID: 20223690 PMCID: PMC2867349 DOI: 10.1016/j.ymgme.2010.02.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Accepted: 02/15/2010] [Indexed: 01/24/2023]
Abstract
Patients with neonatal urea cycle defects (UCDs) typically have high mortality and poor neurological outcome unless they receive liver transplantation. Neurologic outcome may be better with liver transplantation before age one year. We report on a follow up on an initial prospective study performed to assess developmental outcome after early liver transplant using the Griffiths Scales. Developmental testing up to 7years after transplantation showed average developmental quotients (DQs) of 69 for four children who underwent transplantation before one year of age (latest DQs were 47, 63, 95 and 96), and 80 for a patient who underwent transplantation at 3years of age (latest DQ was 88). We conclude that a combination of early liver transplantation, aggressive metabolic management and early childhood intervention improve the neurologic outcome of children with UCDs.
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Affiliation(s)
- Philippe M Campeau
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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49
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Meyburg J, Hoffmann GF. Liver, liver cell and stem cell transplantation for the treatment of urea cycle defects. Mol Genet Metab 2010; 100 Suppl 1:S77-83. [PMID: 20156696 DOI: 10.1016/j.ymgme.2010.01.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 01/13/2010] [Accepted: 01/13/2010] [Indexed: 12/23/2022]
Abstract
Despite advances in pharmacological therapy of urea cycle disorders (UCDs), the overall long-term prognosis is poor, especially for neonatal manifestations. Transplantation of liver tissue or isolated cells appears suitable for transfer of the missing enzyme. Liver transplantation (LT) for UCDs has an excellent 5-year survival rate of approximately 90% and is the only way to completely cure the disease. However, major neurological damage can only be prevented if the operation is performed during the first months of life. Unfortunately, such early LTs have a substantial risk for peri- and postoperative complications, mostly caused by a relatively large liver graft. Liver cell transplantation (LCT) is less invasive than LT, but has still to be regarded as an experimental therapy with about 100 patients treated since its first use in 1993. UCDs are a model disease for LCT, because of the poor prognosis, mainly hepatic enzyme defects, and excellent outcome after LT. So far, 10 children underwent LCT for UCDs with very few technical complications and encouraging clinical results. A first prospective study on its use in severe neonatal UCDs has recently started. However, availability of hepatocytes is limited by the scarcity of donor livers; therefore the use of stem cells is under investigation. Several different cell types may be regarded as liver stem cells, and in vivo transformation into hepatocyte-like cells has been shown in animal studies. However, a clear proof of principle in animal models of human metabolic disease is still missing, which is the prerequisite for clinical application in humans.
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Affiliation(s)
- Jochen Meyburg
- Department of General Pediatrics, University Children's Hospital, Heidelberg, Germany.
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50
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Abstract
The urea cycle is the final pathway for removal of surplus nitrogen from the body, and the major route in humans for detoxification of ammonia. The full complement of enzymes is expressed only in liver. Inherited deficiencies of urea cycle enzymes lead to hyperammonaemia, which causes brain damage. Severe defects present with hyperammonaemic crises in neonates. Equally devastating episodes may occur in previously asymptomatic adults with mild defects, most often X-linked ornithine transcarbamylase (OTC) deficiency. Several mechanisms probably contribute to pathogenesis. Treatment aims to reduce plasma ammonia quickly, reduce production of waste nitrogen, dispose of waste nitrogen using alternative pathways to the urea cycle and replace arginine. These therapies have increased survival and probably improve the neurological outcome. Arginine, sodium benzoate, sodium phenylbutyrate and, less often, sodium phenylacetate are used. Long-term correction is achieved by liver transplantation. Gene therapy for OTC deficiency is effective in animals, and work is ongoing to improve persistence and safety.
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Affiliation(s)
- V Walker
- Department of Clinical Biochemistry, Southampton University Hospitals NHS Trust, Southampton General Hospital, Southampton, UK. valerie.walker @suht.swest.nhs.uk
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