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Ammar M, Safi W, Tlili A, Alila-Fersi O, Frikha F, Chouchen J, Mnif F, Kharrat M, Maalej M, Felhi R, Abid M, Mnif-Feki M, Kacem FH, Fakhfakh F, Mkaouar-Rebai E. A novel TYMP mutation in a family with MNGIE syndrome: Molecular docking, dynamic simulation and computational investigations. Int J Dev Neurosci 2022; 82:626-638. [PMID: 35841120 DOI: 10.1002/jdn.10215] [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: 04/04/2022] [Revised: 06/27/2022] [Accepted: 07/02/2022] [Indexed: 11/11/2022] Open
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE; OMIM 603041) is a rare inherited metabolic disorder mostly caused by mutations in TYMP gene encoding thymidine phosphorylase (TP) protein that affects the mitochondrial nucleotide metabolism. TP, functionally active as a homodimer, is involved in the salvage pathway of pyrimidine nucleosides. MNGIE-like syndrome having an overlapping phenotype of MNGIE was also described and has been associated with mutations in POLG and RRM2B genes. In the present study, we report the molecular investigation of a consanguineous family including two patients with clinical features suggestive of MNGIE syndrome. Bioinformatics analyses were carried out in addition to mtDNA deletion screening and copy number quantification in the blood of the two patients. Whole exome sequencing and Sanger sequencing analyses revealed the segregation in the affected family a novel mutation c.1205T>A (p.L402Q) within the exon 9 of the TYMP gene. In addition, mtDNA analysis revealed the absence of mtDNA deletions and a decrease of the copy number in the blood of the two patients of the studied family. The p.Leu402Gln mutation was located in a conserved amino acid within the α/β domain of the TP protein and several software supported its pathogenicity. In addition, and based on docking and molecular dynamic simulation analyses, results revealed that L402Q caused a conformational change in TP mutated structure and could therefore alter its flexibility and stability. These changes prevent also the formation of stable homodimer leading to non-functional protein with partial or complete loss of its catalytic activity.
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Affiliation(s)
- Marwa Ammar
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Wajdi Safi
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Olfa Alila-Fersi
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Fakher Frikha
- Laboratory of Molecular and Cellular Screening Processes, Center of Biotechnology of Sfax, University of Sfax, Tunisia
| | - Jihen Chouchen
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Fatma Mnif
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Marwa Kharrat
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Marwa Maalej
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Rahma Felhi
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Mohamed Abid
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Mouna Mnif-Feki
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Faten Hadj Kacem
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
| | - Emna Mkaouar-Rebai
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences. University of Sfax, Tunisia
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2
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Gautheron J, Lima L, Akinci B, Zammouri J, Auclair M, Ucar SK, Ozen S, Altay C, Bax BE, Nemazanyy I, Lenoir V, Prip-Buus C, Acquaviva-Bourdain C, Lascols O, Fève B, Vigouroux C, Noel E, Jéru I. Loss of thymidine phosphorylase activity disrupts adipocyte differentiation and induces insulin-resistant lipoatrophic diabetes. BMC Med 2022; 20:95. [PMID: 35341481 PMCID: PMC8958798 DOI: 10.1186/s12916-022-02296-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/10/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Thymidine phosphorylase (TP), encoded by the TYMP gene, is a cytosolic enzyme essential for the nucleotide salvage pathway. TP catalyzes the phosphorylation of the deoxyribonucleosides, thymidine and 2'-deoxyuridine, to thymine and uracil. Biallelic TYMP variants are responsible for Mitochondrial NeuroGastroIntestinal Encephalomyopathy (MNGIE), an autosomal recessive disorder characterized in most patients by gastrointestinal and neurological symptoms, ultimately leading to death. Studies on the impact of TYMP variants in cellular systems with relevance to the organs affected in MNGIE are still scarce and the role of TP in adipose tissue remains unexplored. METHODS Deep phenotyping was performed in three patients from two families carrying homozygous TYMP variants and presenting with lipoatrophic diabetes. The impact of the loss of TP expression was evaluated using a CRISPR-Cas9-mediated TP knockout (KO) strategy in human adipose stem cells (ASC), which can be differentiated into adipocytes in vitro. Protein expression profiles and cellular characteristics were investigated in this KO model. RESULTS All patients had TYMP loss-of-function variants and first presented with generalized loss of adipose tissue and insulin-resistant diabetes. CRISPR-Cas9-mediated TP KO in ASC abolished adipocyte differentiation and decreased insulin response, consistent with the patients' phenotype. This KO also induced major oxidative stress, altered mitochondrial functions, and promoted cellular senescence. This translational study identifies a new role of TP by demonstrating its key regulatory functions in adipose tissue. CONCLUSIONS The implication of TP variants in atypical forms of monogenic diabetes shows that genetic diagnosis of lipodystrophic syndromes should include TYMP analysis. The fact that TP is crucial for adipocyte differentiation and function through the control of mitochondrial homeostasis highlights the importance of mitochondria in adipose tissue biology.
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Affiliation(s)
- Jérémie Gautheron
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France.
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France.
| | - Lara Lima
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
| | - Baris Akinci
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Dokuz Eylul University, 35330, Izmir, Turkey
| | - Jamila Zammouri
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
| | - Martine Auclair
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
| | - Sema Kalkan Ucar
- Department of Pediatrics, Division of Metabolic Diseases, Ege University, 35100, Izmir, Turkey
| | - Samim Ozen
- Department of Pediatrics, Division of Pediatric Endocrinology, Ege University, 35100, Izmir, Turkey
| | - Canan Altay
- Department of Radiology, Dokuz Eylul University, 35100, Izmir, Turkey
| | - Bridget E Bax
- Institute of Molecular and Clinical Sciences, St George's University of London, London, SW17 0RE, UK
| | - Ivan Nemazanyy
- Platform for Metabolic Analyses, Structure Fédérative de Recherche Necker, Inserm, US24/CNRS UMS 3633, 75015, Paris, France
| | - Véronique Lenoir
- Institut Cochin, Université Paris Descartes-CNRS UMR8104, Paris, France
| | - Carina Prip-Buus
- Institut Cochin, Université Paris Descartes-CNRS UMR8104, Paris, France
| | - Cécile Acquaviva-Bourdain
- Service de Biochimie et Biologie Moléculaire Grand Est, Hospices Civils, UM Pathologies Héréditaires du Métabolisme et du Globule Rouge, CHU de Lyon, 69500, Bron, France
| | - Olivier Lascols
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
- Laboratoire commun de Biologie et Génétique Moléculaires, Hôpital Saint-Antoine, AP-HP, 75012, Paris, France
| | - Bruno Fève
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
- Centre National de Référence des Pathologies Rares de l'Insulino-Sécrétion et de l'Insulino-Sensibilité (PRISIS), Service de Diabétologie et Endocrinologie de la Reproduction, Hôpital Saint-Antoine, AP-HP, 75012, Paris, France
| | - Corinne Vigouroux
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France
- Laboratoire commun de Biologie et Génétique Moléculaires, Hôpital Saint-Antoine, AP-HP, 75012, Paris, France
- Centre National de Référence des Pathologies Rares de l'Insulino-Sécrétion et de l'Insulino-Sensibilité (PRISIS), Service de Diabétologie et Endocrinologie de la Reproduction, Hôpital Saint-Antoine, AP-HP, 75012, Paris, France
| | - Esther Noel
- Département de Médecine Interne, Centre Hospitalier Universitaire, 67000, Strasbourg, France
| | - Isabelle Jéru
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université-Inserm UMRS_938, 27 rue Chaligny 75571, 12, Paris Cedex, France.
- Institute of Cardiometabolism and Nutrition (ICAN), CHU Pitié-Salpêtrière - Saint-Antoine, Assistance Publique-Hôpitaux de Paris (AP-HP), 75012, Paris, France.
- Laboratoire commun de Biologie et Génétique Moléculaires, Hôpital Saint-Antoine, AP-HP, 75012, Paris, France.
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Karamitros CS, Somody CM, Agnello G, Rowlinson S. Engineering of the Recombinant Expression and PEGylation Efficiency of the Therapeutic Enzyme Human Thymidine Phosphorylase. Front Bioeng Biotechnol 2021; 9:793985. [PMID: 34976980 PMCID: PMC8718881 DOI: 10.3389/fbioe.2021.793985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 11/12/2021] [Indexed: 12/01/2022] Open
Abstract
Human thymidine phosphorylase (HsTP) is an enzyme with important implications in the field of rare metabolic diseases. Defective mutations of HsTP lead to mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a disease with a high unmet medical need that is associated with severe neurological and gastrointestinal complications. Current efforts focus on the development of an enzyme replacement therapy (ERT) using the Escherichia coli ortholog (EcTP). However, bacterial enzymes are counter-indicated for human therapeutic applications because they are recognized as foreign by the human immune system, thereby eliciting adverse immune responses and raising significant safety and efficacy risks. Thus, it is critical to utilize the HsTP enzyme as starting scaffold for pre-clinical drug development, thus de-risking the safety concerns associated with the use of bacterial enzymes. However, HsTP expresses very poorly in E. coli, whereas its PEGylation, a crucial chemical modification for achieving long serum persistence of therapeutic enzymes, is highly inefficient and negatively affects its catalytic activity. Here we focused on the engineering of the recombinant expression profile of HsTP in E. coli cells, as well as on the optimization of its PEGylation efficiency aiming at the development of an alternative therapeutic approach for MNGIE. We show that phylogenetic and structural analysis of proteins can provide important insights for the rational design of N’-terminus-truncation constructs which exhibit significantly improved recombinant expression levels. In addition, we developed and implemented a criteria-driven rational surface engineering strategy for the substitution of arginine-to-lysine and lysine-to-arginine residues to achieve more efficient, homogeneous and reproducible PEGylation without negatively affecting the enzymatic catalytic activity upon PEGylation. Collectively, our proposed strategies provide an effective way to optimize enzyme PEGylation and E. coli recombinant expression and are likely applicable for other proteins and enzymes.
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Ronchi D, Caporali L, Manenti GF, Meneri M, Mohamed S, Bordoni A, Tagliavini F, Contin M, Piga D, Sciacco M, Saetti C, Carelli V, Comi GP. TYMP Variants Result in Late-Onset Mitochondrial Myopathy With Altered Muscle Mitochondrial DNA Homeostasis. Front Genet 2020; 11:860. [PMID: 32849836 PMCID: PMC7419576 DOI: 10.3389/fgene.2020.00860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/14/2020] [Indexed: 12/02/2022] Open
Abstract
Biallelic TYMP variants result in the mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a juvenile-onset disorder with progressive course and fatal outcome. Milder late-onset (>40 years) form has been rarely described. Gene panel sequencing in a cohort of 60 patients featuring muscle accumulation of mitochondrial DNA (mtDNA) deletions detected TYMP defects in three subjects (5%), two of them with symptom onset in the fifth decade. One of the patients only displayed ptosis and ophthalmoparesis. Biochemical and molecular studies supported the diagnosis. Screening of TYMP is recommended in adult patients with muscle mtDNA instability, even in the absence of cardinal MNGIE features.
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Affiliation(s)
- Dario Ronchi
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy.,Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Leonardo Caporali
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Giulia Francesca Manenti
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Megi Meneri
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Susan Mohamed
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Andreina Bordoni
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | | | - Manuela Contin
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy.,Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM), Università di Bologna, Bologna, Italy
| | - Daniela Piga
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Monica Sciacco
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Cristina Saetti
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy.,Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy.,Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM), Università di Bologna, Bologna, Italy
| | - Giacomo Pietro Comi
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
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Habibzadeh P, Silawi M, Dastsooz H, Bahramjahan S, Ezzatzadegan Jahromi S, Ostovan VR, Yavarian M, Mofatteh M, Faghihi MA. Clinical and molecular characterization of a patient with mitochondrial Neurogastrointestinal Encephalomyopathy. BMC Gastroenterol 2020; 20:142. [PMID: 32384880 PMCID: PMC7206720 DOI: 10.1186/s12876-020-01280-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 04/21/2020] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder caused by mutations in TYMP gene, encoding nuclear thymidine phosphorylase (TP). MNGIE mainly presents with gastrointestinal symptoms and is mostly misdiagnosed in many patients as malabsorption syndrome, inflammatory bowel disease, anorexia nervosa, and intestinal pseudo-obstruction. Up to date, more than 80 pathogenic and likely pathogenic mutations associated with the disease have been reported in patients from a wide range of ethnicities. The objective of this study was to investigate the underlying genetic abnormalities in a 25-year-old woman affected with MNGIE. CASE PRESENTATION The patient was a 25-year-old female referred to our center with the chief complaint of severe abdominal pain and diarrhea for 2 years that had worsened from 2 months prior to admission. The clinical and para-clinical findings were in favor of mitochondrial neurogastrointestinal encephalomyopathy syndrome. Subsequent genetic studies revealed a novel, private, homozygous nonsense mutation in TYMP gene (c. 1013 C > A, p.S338X). Sanger sequencing confirmed the new mutation in the proband. Multiple sequence alignment showed high conservation of amino acids of this protein across different species. CONCLUSION The detected new nonsense mutation in the TYMP gene would be very important for genetic counseling and subsequent early diagnosis and initiation of proper therapy. This novel pathogenic variant would help us establish future genotype-phenotype correlations and identify different pathways related to this disorder.
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Affiliation(s)
- Parham Habibzadeh
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Silawi
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hassan Dastsooz
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Italian Institute for Genomic Medicine (IIGM), University of Turin, Turin, Italy
| | - Shima Bahramjahan
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Vahid Reza Ostovan
- Clinical Neurology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Majid Yavarian
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Mofatteh
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Mohammad Ali Faghihi
- Persian BayanGene Research and Training Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, USA
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Mitochondrial Neurogastrointestinal Encephalomyopathy: Novel Pathogenic Mutation in Thymidine Phosphorylase Gene in a Patient from Cape Verde Islands. Case Rep Neurol Med 2019; 2019:5976410. [PMID: 31885962 PMCID: PMC6927060 DOI: 10.1155/2019/5976410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 08/24/2019] [Accepted: 09/27/2019] [Indexed: 11/17/2022] Open
Abstract
Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE) is a rare autosomal recessive disorder caused by mutations in the gene encoding the Thymidine Phosphorylase (TP). It is clinically characterized by severe gastrointestinal dysmotility, cachexia, palpebral ptosis, ophthalmoparesis, sensorimotor polyneuropathy and leukoencephalopathy. The diagnosis is established by the presence of typical clinical and neuroimaging features, positive family history, and abnormal genetic test. A 19-year-old Cape Verdean patient with a history since childhood of recurrent episodes of nausea, vomiting, diarrhoea and painful abdominal distension associated with progressive motor disability with difficulty in climbing stairs and running and clumsiness with her hands. The diagnostic workup was suggestive of MNGIE. Genetic screening of the TYMP gene identified a novel mutation (c. 1283 G>A). Patients with MNGIE have significant comorbidity and mortality, and they are frequently misdiagnosed. A better acknowledgment of this disorder is essential to permit an earlier diagnosis and to improve disease management.
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Corazza G, Pagan C, Hardy G, Besson G, Lombès A, Acquaviva-Bourdain C, Bouhour F, Gaignard P, Slama A, Roubertie A, Morales RJ, Barth M, Cintas P, Bereau M, Campana-Salort E, Ogier de Baulny H, Schiff M, Benoist JF, Corne C, Joly F. MyoNeuroGastroIntestinal Encephalopathy: Natural History and Means for Early Diagnosis. Gastroenterology 2019; 156:1525-1527.e4. [PMID: 30582904 DOI: 10.1053/j.gastro.2018.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 12/02/2022]
Affiliation(s)
| | - Cécile Pagan
- CHU Lyon, Groupement Hospitalier Est, Centre de biologie et Pathologie Est, F-69500, Bron, France
| | | | | | - Anne Lombès
- INSERM U1016, CNRS UMR 8104, Université Paris 5, F-75014, Paris, France.
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8
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Pacitti D, Levene M, Garone C, Nirmalananthan N, Bax BE. Mitochondrial Neurogastrointestinal Encephalomyopathy: Into the Fourth Decade, What We Have Learned So Far. Front Genet 2018; 9:669. [PMID: 30627136 PMCID: PMC6309918 DOI: 10.3389/fgene.2018.00669] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 12/04/2018] [Indexed: 02/05/2023] Open
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an ultra-rare metabolic autosomal recessive disease, caused by mutations in the nuclear gene TYMP which encodes the enzyme thymidine phosphorylase. The resulting enzyme deficiency leads to a systemic accumulation of the deoxyribonucleosides thymidine and deoxyuridine, and ultimately mitochondrial failure due to a progressive acquisition of secondary mitochondrial DNA (mtDNA) mutations and mtDNA depletion. Clinically, MNGIE is characterized by gastrointestinal and neurological manifestations, including cachexia, gastrointestinal dysmotility, peripheral neuropathy, leukoencephalopathy, ophthalmoplegia and ptosis. The disease is progressively degenerative and leads to death at an average age of 37.6 years. As with the vast majority of rare diseases, patients with MNGIE face a number of unmet needs related to diagnostic delays, a lack of approved therapies, and non-specific clinical management. We provide here a comprehensive collation of the available knowledge of MNGIE since the disease was first described 42 years ago. This review includes symptomatology, diagnostic procedures and hurdles, in vitro and in vivo disease models that have enhanced our understanding of the disease pathology, and finally experimental therapeutic approaches under development. The ultimate aim of this review is to increase clinical awareness of MNGIE, thereby reducing diagnostic delay and improving patient access to putative treatments under investigation.
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Affiliation(s)
- Dario Pacitti
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, United Kingdom
| | - Michelle Levene
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, United Kingdom
| | - Caterina Garone
- MRC Mitochondrial Biology Unit, Cambridge Biomedical, Cambridge, United Kingdom
| | | | - Bridget E. Bax
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, United Kingdom
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Mitochondrial Diseases as Model of Neurodegeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1007:129-155. [DOI: 10.1007/978-3-319-60733-7_8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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10
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Hamzic S, Kummer D, Milesi S, Mueller D, Joerger M, Aebi S, Amstutz U, Largiader CR. Novel Genetic Variants in Carboxylesterase 1 Predict Severe Early-Onset Capecitabine-Related Toxicity. Clin Pharmacol Ther 2017; 102:796-804. [DOI: 10.1002/cpt.641] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/20/2017] [Accepted: 01/23/2017] [Indexed: 12/19/2022]
Affiliation(s)
- S Hamzic
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
- Graduate School for Cellular and Biomedical Sciences; University of Bern; Bern Switzerland
| | - D Kummer
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
- Graduate School for Cellular and Biomedical Sciences; University of Bern; Bern Switzerland
| | - S Milesi
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
| | - D Mueller
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
| | - M Joerger
- Department of Medical Oncology and Hematology; Cantonal Hospital St. Gallen; St. Gallen Switzerland
| | - S Aebi
- Division of Medical Oncology; Cantonal Hospital Lucerne; Lucerne Switzerland
| | - U Amstutz
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
| | - CR Largiader
- Institute of Clinical Chemistry; Inselspital, Bern University Hospital, University of Bern; Bern Switzerland
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Abstract
Mitochondrial disorders (MIDs) due to respiratory-chain defects or nonrespiratory chain defects are usually multisystem conditions [mitochondrial multiorgan disorder syndrome (MIMODS)] affecting the central nervous system (CNS), peripheral nervous system, eyes, ears, endocrine organs, heart, kidneys, bone marrow, lungs, arteries, and also the intestinal tract. Frequent gastrointestinal (GI) manifestations of MIDs include poor appetite, gastroesophageal sphincter dysfunction, constipation, dysphagia, vomiting, gastroparesis, GI pseudo-obstruction, diarrhea, or pancreatitis and hepatopathy. Rare GI manifestations of MIDs include dry mouth, paradontosis, tracheoesophageal fistula, stenosis of the duodeno-jejunal junction, atresia or imperforate anus, liver cysts, pancreas lipomatosis, pancreatic cysts, congenital stenosis or obstruction of the GI tract, recurrent bowel perforations with intra-abdominal abscesses, postprandial abdominal pain, diverticulosis, or pneumatosis coli. Diagnosing GI involvement in MIDs is not at variance from diagnosing GI disorders due to other causes. Treatment of mitochondrial GI disease includes noninvasive or invasive measures. Therapy is usually symptomatic. Only for myo-neuro-gastro-intestinal encephalopathy is a causal therapy with autologous stem-cell transplantation available. It is concluded that GI manifestations of MIDs are more widespread than so far anticipated and that they must be recognized as early as possible to initiate appropriate diagnostic work-up and avoid any mitochondrion-toxic treatment.
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Affiliation(s)
| | - Marlies Frank
- First Medical Department, Krankenanstalt Rudolfstiftung, Vienna, Austria
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12
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Terranova-Barberio M, Roca MS, Zotti AI, Leone A, Bruzzese F, Vitagliano C, Scogliamiglio G, Russo D, D'Angelo G, Franco R, Budillon A, Di Gennaro E. Valproic acid potentiates the anticancer activity of capecitabine in vitro and in vivo in breast cancer models via induction of thymidine phosphorylase expression. Oncotarget 2016; 7:7715-31. [PMID: 26735339 PMCID: PMC4884949 DOI: 10.18632/oncotarget.6802] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 12/23/2015] [Indexed: 12/20/2022] Open
Abstract
The prognosis of patients with metastatic breast cancer remains poor, and thus novel therapeutic approaches are needed. Capecitabine, which is commonly used for metastatic breast cancer in different settings, is an inactive prodrug that takes advantage of elevated levels of thymidine phosphorylase (TP), a key enzyme that is required for its conversion to 5-fluororacil, in tumors. We demonstrated that histone deacetylase inhibitors (HDACi), including low anticonvulsant dosage of VPA, induced the dose- and time-dependent up-regulation of TP transcript and protein expression in breast cancer cells, but not in the non-tumorigenic breast MCF-10A cell line. Through the use of siRNA or isoform-specific HDACi, we demonstrated that HDAC3 is the main isoform whose inhibition is involved in the modulation of TP. The combined treatment with capecitabine and HDACi, including valproic acid (VPA), resulted in synergistic/additive antiproliferative and pro-apoptotic effects in breast cancer cells but not in TP-knockout cells, both in vitro and in vivo, highlighting the crucial role of TP in the synergism observed. Overall, this study suggests that the combination of HDACi (e.g., VPA) and capecitabine is an innovative antitumor strategy that warrants further clinical evaluation for the treatment of metastatic breast cancer.
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Affiliation(s)
| | - Maria Serena Roca
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Andrea Ilaria Zotti
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Alessandra Leone
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Francesca Bruzzese
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Carlo Vitagliano
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Giosuè Scogliamiglio
- Pathology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Domenico Russo
- Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Giovanni D'Angelo
- Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Renato Franco
- Pathology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Alfredo Budillon
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
| | - Elena Di Gennaro
- Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale - IRCCS, Naples, Italy
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Cabrera-Pérez R, Torres-Torronteras J, Vila-Julià F, Ortega FJ, Cámara Y, Barquinero J, Martí R. Prospective therapeutic approaches in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2015.1090307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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14
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Benureau A, Meyer P, Maillet O, Leboucq N, Legras S, Jeziorski E, Fournier-Favre S, Jeandel C, Gaignard P, Slama A, Rivier F, Roubertie A, Carneiro M. [Mitochondrial neurogastrointestinal encephalopathy disease]. Arch Pediatr 2014; 21:1370-4. [PMID: 25282463 DOI: 10.1016/j.arcped.2014.08.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/09/2014] [Accepted: 08/13/2014] [Indexed: 11/18/2022]
Abstract
Mitochondrial neurogastrointestinal encephalopathy disease (MNGIE) is a rare autosomal-recessive syndrome, resulting from mutations in the TYMP gene, located at 22q13. The mutation induces a thymidine phosphorylase (TP) deficit, which leads to a nucleotide pool imbalance and to instability of the mitochondrial DNA. The clinical picture regroups gastrointestinal dysmotility, cachexia, ptosis, ophthalmoplegia, peripheral neuropathy, and asymptomatic leukoencephalopathy. The prognosis is unfavorable. We present the case of a 14-year-old Caucasian female whose symptoms started in early childhood. The diagnosis was suspected after magnetic resonance imaging (MRI), performed given the atypical features of mental anorexia, which revealed white matter abnormalities. She presented chronic vomiting, postprandial abdominal pain, and problems gaining weight accompanied by cachexia. This diagnosis led to establishing proper care, in particular an enteral and parenteral nutrition program. There is no known specific effective treatment, but numerous studies are in progress. In this article, after reviewing the existing studies, we discuss the main diagnostic and therapeutic aspects of the disease. We argue for the necessity of performing a cerebral MRI given the atypical features of a patient with suspected mental anorexia (or when the clinical pattern of a patient with mental anorexia seems atypical), so that MNGIE can be ruled out.
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Affiliation(s)
- A Benureau
- Service de neuropédiatrie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
| | - P Meyer
- Service de neuropédiatrie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France; Inserm U1046, université Montpellier 1, université Montpellier 2, 34000 Montpellier, France
| | - O Maillet
- Service de chirurgie viscérale infantile, hôpital Lapeyronie, 371, avenue du Doyen-Gaston-Giraud, 34295 Montpellier cedex 5, France
| | - N Leboucq
- Service de neuroradiologie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France
| | - S Legras
- Médecine psychologique de l'enfant et de l'adolescent, hôpital Saint-Éloi, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France
| | - E Jeziorski
- Service de maladies infectieuses et immunologie clinique, hôpital Arnaud-de-Villeneuve, 371, avenue du Doyen-Gaston-Giraud, 34295 Montpellier cedex 5, France
| | - S Fournier-Favre
- Service de gastro-entérologie pédiatrique, hôpital Arnaud-de-Villeneuve, 371, avenue du Doyen-Gaston-Giraud, 34295 Montpellier cedex 5, France
| | - C Jeandel
- Service de néphrologie et endocrinologie pédiatrique, hôpital Arnaud-de-Villeneuve, 371, avenue du Doyen-Gaston-Giraud, 34295 Montpellier cedex 5, France
| | - P Gaignard
- Laboratoire de biochimie, hôpital Bicêtre, 78, rue du Général-Leclerc, 94270 Le Kremlin-Bicêtre, France
| | - A Slama
- Laboratoire de biochimie, hôpital Bicêtre, 78, rue du Général-Leclerc, 94270 Le Kremlin-Bicêtre, France
| | - F Rivier
- Service de neuropédiatrie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France; Inserm U1046, université Montpellier 1, université Montpellier 2, 34000 Montpellier, France
| | - A Roubertie
- Service de neuropédiatrie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France; Inserm U 1051, INM, 34000 Montpellier, France
| | - M Carneiro
- Service de neuropédiatrie, hôpital Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France
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Abstract
To highlight differences between early-onset and adult mitochondrial depletion syndromes (MDS) concerning etiology and genetic background, pathogenesis, phenotype, clinical presentation and their outcome. MDSs most frequently occur in neonates, infants, or juveniles and more rarely in adolescents or adults. Mutated genes phenotypically presenting with adult-onset MDS include POLG1, TK2, TyMP, RRM2B, or PEO1/twinkle. Adult MDS manifest similarly to early-onset MDS, as myopathy, encephalo-myopathy, hepato-cerebral syndrome, or with chronic progressive external ophthalmoplegia (CPEO), fatigue, or only minimal muscular manifestations. Diagnostic work-up or treatment is not at variance from early-onset cases. Histological examination of muscle may be normal but biochemical investigations may reveal multiple respiratory chain defects. The outcome appears to be more favorable in adult than in early-onset forms. Mitochondrial depletion syndromes is not only a condition of neonates, infants, or juveniles but rarely also occurs in adults, presenting with minimal manifestations or manifestations like in the early-onset forms. Outcome of adult-onset MDS appears more favorable than early-onset MDS.
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16
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Guillem V, Hernández-Boluda JC, Gallardo D, Buño I, Bosch A, Martínez-Laperche C, de la Cámara R, Brunet S, Martin C, Nieto JB, Martínez C, Pérez A, Montoro J, Garcia-Noblejas A, Solano C. A polymorphism in the TYMP gene is associated with the outcome of HLA-identical sibling allogeneic stem cell transplantation. Am J Hematol 2013; 88:883-9. [PMID: 23813863 DOI: 10.1002/ajh.23523] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/19/2013] [Accepted: 06/20/2013] [Indexed: 11/07/2022]
Abstract
Thymidine phosphorylase (TYMP), an enzyme involved in nucleotide synthesis, has been implicated in critical biological processes such as DNA replication, protection against mutations, and tissue repair. In this work, we retrospectively evaluated the influence of a polymorphism in the TYMP gene (rs112723255; G/A) upon the outcome of 448 patients subjected to allogeneic stem cell transplantation (allo-SCT) from an human leukocyte antigen (HLA)-identical sibling donor. The TYMP genotype of patients correlated with overall survival-carriers of the minor allele (A) being at an increased risk of dying after transplantation (hazard ratio, HR = 1.9; P = 0.004). This effect was mostly due to differences in transplant toxicity-related mortality (HR = 2.5; P = 0.029). In addition, the TYMP genotype of donors was associated with the risk of chronic graft-versus-host disease (GVHD)-carriers of the minor allele being at an increased risk of developing this complication ([HR] = 1.7; P = 0.039). The impact of such polymorphism on the risk of chronic GVHD is limited to patients transplanted in early stage disease (HR = 2.2; P = 0.019). The combination of a donor harboring the minor allele with a patient homozygous for the major allele was associated with the highest risk of chronic GVHD (HR = 2.8; P = 0.008). These findings provide the first evidence of the significant impact of the TYMP genotype upon the clinical outcome of patients treated with HLA-identical sibling allo-SCT.
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Affiliation(s)
- Vicent Guillem
- Department of Hematology and Medical Oncology, Hospital Clínico Universitario de Valencia, Instituto de Investigación Sanitaria INCLIVA, Universitat de Valencia, Valencia, Spain
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17
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Large copy number variations in combination with point mutations in the TYMP and SCO2 genes found in two patients with mitochondrial disorders. Eur J Hum Genet 2013; 22:431-4. [PMID: 23838601 DOI: 10.1038/ejhg.2013.148] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 05/21/2013] [Accepted: 05/27/2013] [Indexed: 11/09/2022] Open
Abstract
Mitochondrial disorders are caused by defects in mitochondrial or nuclear DNA. Although the existence of large deletions in mitochondrial DNA (mtDNA) is well known, deletions affecting whole genes are not commonly described in patients with mitochondrial disorders. Based on the results of whole-genome analyses, copy number variations (CNVs) occur frequently in the human genome and may overlap with many genes associated with clinical phenotypes. We report the discovery of two large heterozygous CNVs on 22q13.33 in two patients with mitochondrial disorders. The first patient harboured a novel point mutation c.667G>A (p.D223N) in the SCO2 gene in combination with a paternally inherited 87-kb deletion. As hypertrophic cardiomyopathy (HCMP) was not documented in the patient, this observation prompted us to compare his clinical features with all 44 reported SCO2 patients in the literature. Surprisingly, the review shows that HCMP was present in only about 50% of the SCO2 patients with non-neonatal onset. In the second patient, who had mitochondrial neurogastrointestinal encephalopathy (MNGIE), a maternally inherited 175-kb deletion and the paternally inherited point mutation c.261G>T (p.E87D) in the TYMP gene were identified.
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18
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Das behinderte Kind. PÄDIATRISCHE GASTROENTEROLOGIE, HEPATOLOGIE UND ERNÄHRUNG 2013. [PMCID: PMC7498781 DOI: 10.1007/978-3-642-24710-1_42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Die Zerebralparese hat eine Prävalenz von 1–2/1000 Lebendgeborene. Diese Zahlen sind in verschiedenen Kulturen relativ stabil und haben sich in den vergangenen 10–20 Jahren kaum verändert. Die Zerebralparese ist als eine prä-, peri- oder unmittelbar postpartal erworbene, nichtprogrediente Schädigung des Gehirns definiert. Es werden 3 Formen unterschieden: die spastische, die hypoton-ataktische und die dyston-athetoide Zerebralparese. Neben der Zerebralparese können auch andere klinische Krankheitsbilder mit einer muskulären Hypotonie oder einer Spastizität im Rahmen einer progredienten, z. B. metabolischen Erkrankung als Zeichen der neurologischen Störung zu schweren Behinderungen führen und mit klinisch relevanten gastrointestinalen Dysfunktionen und Symptomen assoziiert sein, die fast immer einer Langzeitbehandlung bedürfen. Etwa 60 % der Patienten zeigen eine Dysphagie, 40 % eine chronische pulmonale Mikroaspiration und mindestens 30 % einen klinisch signifikanten gastroösophagealen Reflux, eine Gastritis und abdominale Schmerzen. Mindestens 75 % der neurologisch behinderten Kinder leiden unter einer Obstipation, etwa ein Drittel zeigt die Merkmale einer Fehlund Unterernährung, wobei es große Unterschiede gibt, je nach Schweregrad der Behinderung.
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Sekino Y, Inamori M, Yamada E, Ohkubo H, Sakai E, Higurashi T, Iida H, Hosono K, Endo H, Nonaka T, Takahashi H, Koide T, Abe Y, Gotoh E, Koyano S, Kuroiwa Y, Maeda S, Nakajima A. Characteristics of intestinal pseudo-obstruction in patients with mitochondrial diseases. World J Gastroenterol 2012; 18:4557-62. [PMID: 22969229 PMCID: PMC3435781 DOI: 10.3748/wjg.v18.i33.4557] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 03/09/2012] [Accepted: 03/20/2012] [Indexed: 02/06/2023] Open
Abstract
AIM: To reveal the frequency, characteristics and prog-nosis of chronic intestinal pseudo-obstruction (CIP) in mitochondrial disease patients.
METHODS: Between January 2000 and December 2010, 31 patients (13 males and 18 females) were diagnosed with mitochondrial diseases at our hospital. We conducted a retrospective review of the patients’ sex, subclass of mitochondrial disease, age at onset of mitochondrial disease, frequency of CIP and the age at its onset, and the duration of survival. The age at onset or at the first diagnosis of the disorder that led to the clinical suspicion of mitochondrial disease was also examined.
RESULTS: Twenty patients were sub-classified with mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS), 8 with chronic progressive external ophthalmoplegia (CPEO), and 3 with myoclonus epilepsy associated with ragged-red fibers (MERRF). Nine patients were diagnosed with CIP, 8 of the 20 (40.0%) patients with MELAS, 0 of the 8 (0.0%) patients with CPEO, and 1 of the 3 (33.3%) patients with MERRF. The median age (range) at the diagnosis and the median age at onset of mitochondrial disease were 40 (17-69) and 25 (12-63) years in patients with CIP, and 49 (17-81) and 40 (11-71) years in patients without CIP. During the survey period, 5 patients (4 patients with MELAS and 1 with CPEO) died. The cause of death was cardiomyopathy in 2 patients with MELAS, cerebral infarction in 1 patient with MELAS, epilepsy and aspiration pneumonia in 1 patient with MELAS, and multiple metastases from gastric cancer and aspiration pneumonia in 1 patient with CPEO.
CONCLUSION: Patients with CIP tend to have disorders that are suspected to be related to mitochondrial diseases at younger ages than are patients without CIP.
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Hirano M, Garone C, Quinzii CM. CoQ(10) deficiencies and MNGIE: two treatable mitochondrial disorders. Biochim Biophys Acta Gen Subj 2012; 1820:625-31. [PMID: 22274133 DOI: 10.1016/j.bbagen.2012.01.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Revised: 12/28/2011] [Accepted: 01/10/2012] [Indexed: 12/25/2022]
Abstract
BACKGROUND Although causative mutations have been identified for numerous mitochondrial disorders, few disease-modifying treatments are available. Two examples of treatable mitochondrial disorders are coenzyme Q(10) (CoQ(10) or ubiquinone) deficiency and mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). SCOPE OF REVIEW Here, we describe clinical and molecular features of CoQ(10) deficiencies and MNGIE and explain how understanding their pathomechanisms have led to rationale therapies. Primary CoQ(10) deficiencies, due to mutations in genes required for ubiquinone biosynthesis, and secondary deficiencies, caused by genetic defects not directly related to CoQ(10) biosynthesis, often improve with CoQ(10) supplementation. In vitro and in vivo studies of CoQ(10) deficiencies have revealed biochemical alterations that may account for phenotypic differences among patients and variable responses to therapy. In contrast to the heterogeneous CoQ(10) deficiencies, MNGIE is a single autosomal recessive disease due to mutations in the TYMP gene encoding thymidine phosphorylase (TP). In MNGIE, loss of TP activity causes toxic accumulations of the nucleosides thymidine and deoxyuridine that are incorporated by the mitochondrial pyrimidine salvage pathway and cause deoxynucleoside triphosphate pool imbalances, which, in turn cause mtDNA instability. Allogeneic hematopoetic stem cell transplantation to restore TP activity and eliminate toxic metabolites is a promising therapy for MNGIE. MAJOR CONCLUSIONS CoQ(10) deficiencies and MNGIE demonstrate the feasibility of treating specific mitochondrial disorders through replacement of deficient metabolites or via elimination of excessive toxic molecules. GENERAL SIGNIFICANCE Studies of CoQ(10) deficiencies and MNGIE illustrate how understanding the pathogenic mechanisms of mitochondrial diseases can lead to meaningful therapies. This article is part of a Special Issue entitled: Biochemistry of Mitochondria, Life and Intervention 2010.
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Affiliation(s)
- Michio Hirano
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
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A second MNGIE patient without typical mitochondrial skeletal muscle involvement. Neurol Sci 2010; 31:491-4. [PMID: 20232099 DOI: 10.1007/s10072-010-0225-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 01/14/2010] [Indexed: 10/19/2022]
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease caused by mutations in the gene encoding thymidine phosphorylase (TYMP). Clinically, MNGIE is characterized by gastrointestinal dysmotility, cachexia, ptosis, ophthalmoparesis, peripheral neuropathy and leukoencephalopathy. Most MNGIE patients have signs of mitochondrial dysfunction in skeletal muscle at morphological and enzyme level, as well as mitochondrial DNA depletion, multiple deletions and point mutations. A case without mitochondrial skeletal muscle involvement and with a TYMP splice-acceptor site mutation (c. 215-1 G>C) has been reported. Here, we describe an Italian patient with the same mutation and without mitochondrial skeletal muscle involvement, suggesting a possible genotype-phenotype correlation.
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22
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Collated mutations in mitochondrial DNA (mtDNA) depletion syndrome (excluding the mitochondrial gamma polymerase, POLG1). Biochim Biophys Acta Mol Basis Dis 2009; 1792:1109-12. [DOI: 10.1016/j.bbadis.2009.08.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Accepted: 08/27/2009] [Indexed: 01/09/2023]
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Amiot A, Tchikviladzé M, Joly F, Slama A, Hatem DC, Jardel C, Messing B, Lombès A. Frequency of mitochondrial defects in patients with chronic intestinal pseudo-obstruction. Gastroenterology 2009; 137:101-9. [PMID: 19344718 DOI: 10.1053/j.gastro.2009.03.054] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 03/04/2009] [Accepted: 03/23/2009] [Indexed: 01/29/2023]
Abstract
BACKGROUND & AIMS Chronic intestinal pseudo-obstruction (CIPO) is a rare disorder caused by intestinal dysmotility and characterized by chronic symptoms suggesting bowel obstruction in the absence of fixed, occluding lesions. CIPO has been associated with primary defects of the mitochondrial oxidative phosphorylation pathway, although the frequency of mitochondrial disorders in patients with CIPO is unknown. This study evaluates mitochondrial function in patients with CIPO. METHODS A retrospective study was performed of data collected from 80 CIPO patients at a tertiary centre over a 25-year period. Mitochondrial disorders were detected by analysis of serum lactate and thymidine phosphorylase activities, brain magnetic resonance images, and muscle biopsies. Genes encoding thymidine phosphorylase, mitochondrial DNA tRNA(leu(UUR)) or tRNA(lys), and DNA polymerase-gamma were analyzed for mutations. RESULTS Mitochondrial defects were identified in 15 patients (10 women; median age at diagnosis 32 years), representing 19% of the study cohort. All 15 patients had extra-digestive symptoms, 5 had mutations in the thymidine phosphorylase gene, 2 had mutations in tRNA(leu(UUR)), and 5 had mutations in the DNA polymerase-gamma gene. No genetic defect was detected in 3 of the patients with mitochondrial disorders. Patients with mitochondrial CIPO differed from patients without mitochondrial defects in their very severe nutritional status (frequent and long-term requirement for parenteral nutrition) and poor prognosis (frequent digestive and neurologic complications that led to a high incidence of premature death). CONCLUSION Mitochondrial disorders seem to be an important cause of CIPO. Patients with CIPO, especially severe cases with associated neurologic symptoms, should be tested for mitochondrial defects.
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Affiliation(s)
- Aurélien Amiot
- AP-HP, Hôpital Beaujon, Pôle des maladies de l'appareil digestif, Service de Gastroentérologie et d'assistance nutritive, Clichy, France
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24
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Taanman JW, Daras M, Albrecht J, Davie CA, Mallam EA, Muddle JR, Weatherall M, Warner TT, Schapira AHV, Ginsberg L. Characterization of a novel TYMP splice site mutation associated with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Neuromuscul Disord 2008; 19:151-4. [PMID: 19056268 DOI: 10.1016/j.nmd.2008.11.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 10/20/2008] [Accepted: 11/03/2008] [Indexed: 12/13/2022]
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy is an autosomal recessive disorder caused by loss-of-function mutations in the thymidine phosphorylase gene (TYMP). We report here a patient compound heterozygous for two TYMP mutations: a novel g.4009G>A transition affecting the consensus splice donor site of intron 9, and a previously reported g.675G>C splice site mutation. The novel mutation causes exon 9 skipping but leaves the reading frame intact; however, TYMP protein was not detected by immunoblot analysis, suggesting that neither mutant allele is expressed as protein. The patient's fibroblasts showed gradual loss of the mitochondrial DNA-encoded subunit I of cytochrome-c oxidase, suggesting a progressive mitochondrial DNA defect in culture.
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Affiliation(s)
- Jan-Willem Taanman
- Department of Clinical Neurosciences, Institute of Neurology, University College London, Rowland Hill Street, London, United Kingdom.
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25
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Lara MC, Valentino ML, Torres-Torronteras J, Hirano M, Martí R. Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE): Biochemical Features and Therapeutic Approaches. Biosci Rep 2007; 27:151-63. [PMID: 17549623 DOI: 10.1007/s10540-007-9043-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Over the last 15 years, important research has expanded our knowledge of the clinical, molecular genetic, and biochemical features of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). The characterization of mitochondrial involvement in this disorder and the seminal determination of its genetic cause, have opened new possibilities for more detailed and deeper studies on the pathomechanisms in this progressive and fatal disease. It has been established that MNGIE is caused by mutations in the gene encoding thymidine phosphorylase (TP), which lead to absolute or nearly complete loss of its catalytic activity, producing systemic accumulations of its substrates, thymidine (dThd) and deoxyuridine (dUrd). Findings obtained from in vitro and in vivo studies indicate that the biochemical imbalances specifically impair mitochondrial DNA (mtDNA) replication, repair, or both leading to mitochondrial dysfunction. We have proposed that therapy for MNGIE should be aimed at reducing the concentrations of these toxic nucleosides to normal or nearly normal levels. The first treatment, allogeneic stem-cell transplantation (alloSCT) reported in 2006, produced a nearly full biochemical correction of the dThd and dUrd imbalances in blood. Clinical follow-up of this and other patients receiving alloSCT is necessary to determine whether this and other therapies based on a permanent restoration of TP will be effective treatment for MNGIE.
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Affiliation(s)
- M C Lara
- Centre d'Investigacions en Bioquímica i Biologia Molecular, Institut de Recerca Hospital Universitari Vall d'Hebron and Centre for Biomedical Research on Rare Diseases (CIBERER), ISCIII, P. Vall d'Hebron 119-129, 08035, Barcelona, Spain
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Kintarak J, Liewluck T, Sangruchi T, Hirano M, Kulkantrakorn K, Muengtaweepongsa S. A novel ECGF1 mutation in a Thai patient with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Clin Neurol Neurosurg 2007; 109:613-6. [PMID: 17544574 DOI: 10.1016/j.clineuro.2007.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2007] [Revised: 04/05/2007] [Accepted: 04/19/2007] [Indexed: 11/19/2022]
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive, multisystem disorder, which is clinically defined by ptosis, ophthalmoparesis, gastrointestinal dysmotility, cachexia, peripheral neuropathy, and leukoencephalopathy. MNGIE is caused by mutations in the nuclear gene, endothelial cell growth factor 1 (ECGF1), encoding thymidine phosphorylase (TP). ECGF1 mutations cause severe loss of TP activity, abnormal accumulations of thymidine and deoxyuridine in plasma, and alterations of mitochondrial DNA. Here, we report the first Thai patient with MNGIE confirmed genetically by the identification of a homozygous novel ECGF1 gene mutation, c.100insC, which causes a frameshift and premature truncation of TP protein.
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Affiliation(s)
- Jutatip Kintarak
- Department of Pathology, Faculty of Medicine, Thammasat University, Patumthani, Thailand.
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Ashley N, Adams S, Slama A, Zeviani M, Suomalainen A, Andreu AL, Naviaux RK, Poulton J. Defects in maintenance of mitochondrial DNA are associated with intramitochondrial nucleotide imbalances. Hum Mol Genet 2007; 16:1400-11. [PMID: 17483096 DOI: 10.1093/hmg/ddm090] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Defects in mtDNA maintenance range from fatal multisystem childhood diseases, such as Alpers syndrome, to milder diseases in adults, including mtDNA depletion syndromes (MDS) and familial progressive external ophthalmoplegia (AdPEO). Most are associated with defects in genes involved in mitochondrial deoxynucleotide metabolism or utilization, such as mutations in thymidine kinase 2 (TK2) as well as the mtDNA replicative helicase, Twinkle and gamma polymerase (POLG). We have developed an in vitro system to measure incorporation of radiolabelled dNTPs into mitochondria of saponin permeabilized cells. We used this to compare the rates of mtDNA synthesis in cells from 12 patients with diseases of mtDNA maintenance. We observed reduced incorporation of exogenous alpha (32)P-dTTP in fibroblasts from a patient with Alpers syndrome associated with the A467T substitution in POLG, a patient with dGK mutations, and a patient with mtDNA depletion of unknown origin compared to controls. However, incorporation of alpha (32)P-dTTP relative to either cell doubling time or alpha (32)P-dCTP incorporation was increased in patients with thymidine kinase deficiency or PEO as the result of TWINKLE mutations compared with controls. The specific activity of newly synthesized mtDNA depends on the size of the endogenous pool diluting the exogenous labelled nucleotide. Our result is consistent with a deficiency in the intramitochondrial pool of dTTP relative to dCTP in cells from patients with TK2 deficiency and TWINKLE mutations. Such DNA precursor asymmetry could cause pausing of the replication complex and hence exacerbate the propensity for age-related mtDNA mutations. Because deviations from the normal concentrations of dNTPs are known to be mutagenic, we suggest that intramitochondrial nucleotide imbalance could underlie the multiple mtDNA mutations observed in these patients.
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Affiliation(s)
- Neil Ashley
- Mitochondrial Genetics Group, Nuffield Department of Obstetrics and Gynaecology, Level 3, Women's Centre,The John Radcliffe Hospital, Oxford OX3 9DU, UK
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Schüpbach WMM, Vadday KM, Schaller A, Brekenfeld C, Kappeler L, Benoist JF, Xuan-Huong CNT, Burgunder JM, Seibold F, Gallati S, Mattle HP. Mitochondrial neurogastrointestinal encephalomyopathy in three siblings. J Neurol 2007; 254:146-53. [PMID: 17294068 DOI: 10.1007/s00415-006-0255-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2006] [Accepted: 04/12/2006] [Indexed: 01/19/2023]
Abstract
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder in which a nuclear mutation of the thymidine phosphorylase (TP) gene causes mitochondrial genomic dysfunction. Patients suffer from gastrointestinal dysmotility, cachexia, ptosis, external ophthalmoparesis, myopathy and polyneuropathy. Magnetic resonance imaging (MRI) shows leukoencephalopathy. We describe clinical, genetic and neuroradiological features of three brothers affected with MNGIE. Clinical examination, laboratory analyses, MRI and magnetic resonance spectroscopy (MRS) of the brain, and genetic analysis have been performed in all six members of the family with the three patients with MNGIE. Two of them are monozygous twins. They all suffered from gastrointestinal dysmotility, cachexia, ophthalmoplegia, muscular atrophies, and polyneuropathy. Urinary thymidine was elevated in the patients related to the severity of clinical disease, and urinary thymidine (normally not detectable) was also found in a heterozygous carrier. Brain MRI showed leukoencephalopathy in all patients; however, their cognitive functioning was normal. Brain MRS demonstrated reduced N-acetylaspartate and choline in severely affected areas. MRI of heterozygous carriers was normal. A new mutation (T92N) in the TP gene was identified. Urinary thymidine is for the first time reported to be detectable in a heterozygous carrier. MRS findings indicate loss of neurons, axons, and glial cells in patients with MNGIE, but not in heterozygous carriers.
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Affiliation(s)
- W M M Schüpbach
- Department of Neurology, University Hospital-Inselspital, 3010 Bern, Switzerland
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Gamez J, Minoves T. Abnormal brainstem auditory evoked responses in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): Evidence of delayed central conduction time. Clin Neurophysiol 2006; 117:2385-91. [PMID: 16949865 DOI: 10.1016/j.clinph.2006.07.138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 07/04/2006] [Accepted: 07/10/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To assess the usefulness of brain auditory evoked potentials (BAEPs) in the study of asymptomatic white matter alterations in brain MRI observed in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) patients. METHODS The authors studied the neurophysiological characteristics of the BAEPs in four genetically confirmed MNGIE patients who presented varying degrees of leukoencephalopathy in brain MRI. RESULTS Prolonged I-III and I-V interpeak latencies were the most common abnormalities found, with a correlation between the extent of brain MRI lesions and BAEPs. CONCLUSIONS The findings suggest a delayed central conduction time along the brainstem. BAEPs may be useful in the neurophysiological evaluation of central white matter lesions in MNGIE. Similar neurophysiological findings have been reported in other myelin disorders in the central nervous system. SIGNIFICANCE The BAEPs abnormalities identified should be interpreted as an indirect sign of CNS involvement in MNGIE patients and provide comprehensive and integrated information concerning brainstem dysfunction. Further studies are necessary in order to identify whether there is a correlation between BAEPs and the clinical progression of the disease.
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Affiliation(s)
- Josep Gamez
- Department of Neurology, Hospital Universitari Vall d'Hebron, UAB, Barcelona, Spain.
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Joly F, Amiot A, Coffin B, Lavergne-Slove A, Messing B, Bouhnik Y. Pseudo-obstruction intestinale chronique. ACTA ACUST UNITED AC 2006; 30:975-85. [PMID: 17075444 DOI: 10.1016/s0399-8320(06)73359-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Chronic intestinal pseudo-obstruction (CIPO) is a disease characterized by episodes resembling mechanical obstruction in the absence of organic, systemic, or metabolic disorders. Pseudo-obstruction is an uncommon condition and can result from primary (40%) or secondary (60%) causes. The most common symptoms are nausea, vomiting, abdominal distension, abdominal pain and constipation or diarrhea. These symptoms are usually present many years before CIPO diagnosis. They can lead to severe electrolyte disorders and malnutrition. Principles for management of patients with CIPO are: to establish a correct clinical diagnosis in excluding mechanical obstruction; to perform a symptomatic and physiologic assessment of the gastrointestinal tract involved; to look for extra-intestinal manifestations, especially for myopathy and neuropathy; to discuss in some cases a surgery for full-thickness intestinal biopsies, and/or a neuromuscular biopsy in case of mitochondrial cytopathy suspicion. The management is primarily focused on symptom control and nutritional support to prevent weight loss and malnutrition. Treatment of CIPO includes prokinetic agents which may help to reduce gastrointestinal symptoms Courses of antibiotics may be needed in patients with symptoms suggestive of bacterial overgrowth. When necessary, enteral nutrition is preferred. In carefully selected patients, feeding jejunostomy with or without decompression gastrostomy may be tried. Long term parenteral nutrition should be reserved for patients who can not tolerate enteral nutrition. Intestinal transplantation can be discussed in selected patients.
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Affiliation(s)
- Francisca Joly
- Service de Gastroentérologie et d'Assistance nutritive, Hôpital Beaujon, 100 Boulevard du Général Leclerc, Clichy-la-Garenne, 92110 Clichy cedex
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Blondon H, Polivka M, Joly F, Flourie B, Mikol J, Messing B. Digestive smooth muscle mitochondrial myopathy in patients with mitochondrial-neuro-gastro-intestinal encephalomyopathy (MNGIE). ACTA ACUST UNITED AC 2005; 29:773-8. [PMID: 16294144 DOI: 10.1016/s0399-8320(05)86346-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We report 3 new cases of Mitochondrial-Neuro-Gastro-Intestinal Encephalomyopathy (MNGIE) (or Pseudo-Obstruction-Leukoencephalopathy-Intestinal-Pseudoobstruction Syndrome [POLIP]), a rare disease that associates chronic intestinal pseudo-obstruction (CIPO) and neurological symptoms. A review of the 72 reported cases together with these 3 cases revealed that this condition was associated with (a) a specific cluster of neurological symptoms including leukoencephalopathy (96%), polyneuropathy (96%), ophthalmoplegia (91%) and hearing loss (55%); (b) a CIPO syndrome with the presence of small bowel diverticulae (53%); and (c) mitochondrial cytopathy in 36 of the 37 tested patients (2 of our 3 cases), and thymidine phosphorylase gene mutations in all the 37 tested patients (2 of our cases). The etiology of POLIP/MNGIE syndrome appears therefore to be due to a mitochondrial cytopathy secondary to thymidine phosphorylase gene mutation(s). In 3 cases, including 2 of our 3 patients, mitochondrial abnormalities were evidenced at the ultrastructural level in digestive smooth muscle demonstrating that the pathogenesis of gastrointestinal involvement was directly related to mitochondrial alterations in digestive smooth muscle cells.
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Affiliation(s)
- Hugues Blondon
- Service d'Hépato-gastroentérologie et d'Assistance Nutritive, Hôpital Lariboisière, 75475 Paris Cedex 10
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