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Falsaperla R, Sortino V, Vitaliti G, Privitera GF, Ruggieri M, Fusto G, Pappalardo XG. GLUT-1DS resistant to ketogenic diet: from clinical feature to in silico analysis. An exemplificative case report with a literature review. Neurogenetics 2024; 25:69-78. [PMID: 38190079 DOI: 10.1007/s10048-023-00742-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 12/31/2023] [Indexed: 01/09/2024]
Abstract
Glucose transporter type 1 deficiency syndrome (GLUT-1DS) is characterized by alterations in glucose translocation through the blood-brain barrier (BBB) due to mutation involving the GLUT-1 transporter. The fundamental therapy is ketogenic diet (KD) that provide an alternative energetic substrate - ketone bodies that across the BBB via MCT-1 - for the brain. Symptoms are various and include intractable seizure, acquired microcephalia, abnormal ocular movement, movement disorder, and neurodevelopment delay secondary to an energetic crisis for persistent neuroglycopenia. KD is extremely effective in controlling epileptic seizures and has a positive impact on movement disorders and cognitive impairment. Cases of KD resistance are rare, and only a few of them are reported in the literature, all regarding seizure. Our study describes a peculiar case of GLUT-1DS due to a new deletion involving the first codon of SLC2A1 gene determining a loss of function with a resistance to KD admitted to hospital due to intractable episodes of dystonia. This patient presented a worsening of symptomatology at higher ketonemia values but without hyperketosis and showed a complete resolution of symptomatology while maintaining low ketonemia values. Our study proposes an in-silico genomic and proteomic analysis aimed at explaining the atypical response to KD exhibited by our patient. In this way, we propose a new clinical and research approach based on precision medicine and molecular modelling to be applied to patients with GLUT-1DS resistant to first-line treatment with ketogenic diet by in silico study of genetic and altered protein product.
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Affiliation(s)
- Raffaele Falsaperla
- Neonatal Intensive Care Unit and Neonatal Accompaniment Unit, Azienda Ospedaliero-Universitaria Policlinico "Rodolico-San Marco," San Marco Hospital, University of Catania, Catania, Italy.
- Unit of Pediatrics and Pediatric Emergency, Azienda Ospedaliero-Universitaria Policlinico, "Rodolico-San Marco," San Marco Hospital, Catania, Italy.
| | - Vincenzo Sortino
- Unit of Pediatrics and Pediatric Emergency, Azienda Ospedaliero-Universitaria Policlinico, "Rodolico-San Marco," San Marco Hospital, Catania, Italy
| | - Giovanna Vitaliti
- Unit of Pediatrics and Pediatric Emergency, Azienda Ospedaliero-Universitaria Policlinico, "Rodolico-San Marco," San Marco Hospital, Catania, Italy
| | | | - Martino Ruggieri
- Unit of Clinical Pediatrics, Department of Clinical and Experimental Medicine, University of Catania, AOU "Policlinico," PO "G. Rodolico", Via S. Sofia, 78, 95124, Catania, Italy
| | - Gaia Fusto
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Catania, Italy
| | - Xena Giada Pappalardo
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Catania, Italy
- National Council of Research, Institute for Research and Biomedical Innovation (IRIB), Unit of Catania, Catania, Italy
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Horckmans S, Van Paesschen W. GLUT-1 transporter deficiency presenting as hemiplegic migraine in an adult. Acta Neurol Belg 2024; 124:699-700. [PMID: 37733158 DOI: 10.1007/s13760-023-02387-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 09/09/2023] [Indexed: 09/22/2023]
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Varesio C, Zanaboni MP, Pasca L, Provenzi L, Ferraris C, Tagliabue A, Pezzotti E, Carpani A, Veggiotti P, DE Giorgis V. Novel insight into GLUT1 deficiency syndrome: screening for emotional and behavioral problems in youths following ketogenic diet. Minerva Pediatr (Torino) 2024; 76:189-196. [PMID: 33820407 DOI: 10.23736/s2724-5276.21.05923-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Glucose transporter type 1 deficiency syndrome (GLUT1DS) is a rare disorder with a broad spectrum of neurological manifestations. The ketogenic diet (KD) is, to date, the gold standard treatment. Behavioral problems, well recognized in patients with chronic conditions, have not been, so far, deeply investigated in GLUT1DS patients. We performed an exploratory study to assess the risk of emotional and behavioral problems and investigated the potential role of influencing factors related to the pathology itself or KD treatment. METHODS This was a mono-center retrospective study involving youths with GLUT1Ds treated with KD and a group of migraine patients age- and gender-matched. Patients were included if the main caregiver completed the Child Behavior Check List 6-18 (CBCL). Descriptive statistics for demographic and clinical data and questionnaire scores were computed. Correlational analyses were used to assess the potential associations of clinical variables and age and time from KD introduction with CBCL scores in GLUT1DS patients. RESULTS We enrolled nine youths with GLUT1DS and 9 with migraine. In the GLUT1DS group, none of the mean scores of the CBCL items fell within the borderline/clinical range, except for social problems located in the borderline range. Investigation for influencing factors revealed the patient's age related to withdrawn/depressive (r=0.709, P=0.032) and social problems (r=.684, P=0.042). Time from the introduction of KD was related to social problems (r=.827, P=0.006). From the comparison with the scores obtained from migraine patients, significantly higher scores emerged in the latter group in internalizing problems (Z=-2.48, P=0.01), externalizing problems (Z=-3.49, P<0.001), anxious/depressed subscale (Z=-2.37, P=0.014), somatic complaints subscale (Z=-2.624, P=0.008), aggressive behavior subscale (Z=-2.539, P=0.011). CONCLUSIONS Although highly exploratory in its nature, this study provides a novel insight into GLUT1DS. Our data suggested that the risk for internalizing problems in GLUT1DS youths was related to higher age and higher time elapsed from KD introduction. They occurred at a sub-clinical level, making them difficult to detect, if not expressly and systematically investigated.
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Affiliation(s)
- Costanza Varesio
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy -
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy -
| | - Martina P Zanaboni
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
| | - Ludovica Pasca
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Livio Provenzi
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
| | - Cinzia Ferraris
- Nutrition and Eating Disorder Research Center, Department of Public Health, Experimental and Forensic Medicine University of Pavia, Pavia, Italy
| | - Anna Tagliabue
- Nutrition and Eating Disorder Research Center, Department of Public Health, Experimental and Forensic Medicine University of Pavia, Pavia, Italy
| | - Elena Pezzotti
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Adriana Carpani
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
| | - Pierangelo Veggiotti
- Unit of Pediatric Neurology, Vittore Buzzi Hospital, Milan, Italy
- Department of Biomedical and Clinical Sciences, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Valentina DE Giorgis
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Pavia, Italy
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Falsaperla R, Sortino V, Striano P, Kluger G, Ramantani G, Ruggieri M. Is ketogenic diet a 'precision medicine'? Recent developments and future challenges. Eur J Paediatr Neurol 2024; 48:13-16. [PMID: 37984007 DOI: 10.1016/j.ejpn.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/26/2023] [Accepted: 11/09/2023] [Indexed: 11/22/2023]
Abstract
Recently, precision medicine has attracted much attention in the management of epilepsies, but it remains unclear if the increasingly utilized ketogenic diet approaches can truly be considered precision medicine in all epilepsy treatment. Currently, it is the standard treatment for patients with GLUT1 deficiency and the latest NICE guidelines highlight ketogenic diet as a therapeutic option for multi-drug resistant epilepsy patients. Ketogenic diet is presumed to be a precision medicine tool when applied to the treatment of seizures secondary to GLUT1 transporter deficiency. In contrast, the genetic and epigenetic mechanisms modulated by ketogenic diet and underlying its efficacy in other epilepsy types can only be hypothesized to relate to mechanisms of neuroprotection, neuromodulation, and reduction of neuroinflammation. Early ketogenic diet initiation in well-selected patients, would allow immediate action in the direction of neuroprotection and modulation of neuroinflammation, ensuring higher success rates and lower "cost" to the patient in terms of quality of life and comorbidities. These considerations have fueled an increasing interest in investigating the efficacy, side effects, and adherence to long-term use of the ketogenic diet in epilepsy treatment in large contemporary cohorts, available within the scope of multicentric collaborations, such as the European Network for Therapy in Rare Epilepsies (NETRE). Future directions should involve the use of precision medicine, applied to each patient with the help of "omics", whose use should be expanded and inclusive.
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Affiliation(s)
- Raffaele Falsaperla
- Neonatal Intensive Care Unit and Neonatal Accompaniment Unit, Azienda Ospedaliero-Universitaria Policlinico "Rodolico-San Marco", San Marco Hospital, University of Catania, Catania, Italy; Unit of Pediatrics and Pediatric Emergency, Azienda Ospedaliero-Universitaria Policlinico, "Rodolico-San Marco", San Marco Hospital, Catania, Italy.
| | - Vincenzo Sortino
- Unit of Pediatrics and Pediatric Emergency, Azienda Ospedaliero-Universitaria Policlinico, "Rodolico-San Marco", San Marco Hospital, Catania, Italy; Postgraduate Training Program in Pediatrics, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Pasquale Striano
- IRCCS 'G. Gaslini Institute', Genoa, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
| | - Gerhard Kluger
- Research Institute for Rehabilitation, Transition, and Palliation, PMU Salzburg, Salzburg, Austria; Epilepsy Center for Children and Adolescents, Schön Clinic Vogtareuth, Vogtareuth, Germany
| | - Georgia Ramantani
- Department of Neuropediatrics, University Children's Hospital Zurich, and University of Zurich, Zurich, Switzerland.
| | - Martino Ruggieri
- Unit of Clinical Pediatrics, Department of Clinical and Experimental Medicine, University of Catania, AOU "Policlinico", PO "G. Rodolico", via S. Sofia, 78, 95124, Catania, Italy
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Li Z, Han C, Chen G, Zhao H. [Analysis of clinical phenotype and variant of SLC2A1 gene in a Chinese pedigree affected with glucose transporter 1 deficiency syndrome]. Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2022; 39:884-888. [PMID: 35929942 DOI: 10.3760/cma.j.cn511374-20210422-00271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
OBJECTIVE To analyze the clinical phenotype and variant of SLC2A1 gene in a Chinese pedigree affected with glucose transporter type 1 deficiency syndrome (GLUT1-DS). METHODS Clinical data of a child who was treated due to delayed motor and language development and his family members were collected. DNA was extracted from peripheral blood samples and subjected to high-throughput medical exome sequencing. Candidate variant was verified by Sanger sequencing of his parents and sister. The genotype-phenotype correlation was explored. RESULTS The child, his mother and sister had common manifestations such as delayed mental and motor development, poor exercise tolerance, easy fatigue and paroxysmal dystonia, but the difference was that the child and his mother had microcephaly and seizures, while his sister did not. A heterozygous missense SLC2A1 c.191T>C (p.L64P) variant was identified in all affected members, which was unreported previously. CONCLUSION The missense SLC2A1 c.191T>C (p.L64P) variant probably underlay the disease in the proband and his mother and sister. Variability of the clinical phenotypes has reflected the genetic and phenotypic diversity of GLUT1-DS. Detection of the novel variant has enriched the spectrum of GLUT1-DS mutations.
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Affiliation(s)
- Zhen Li
- Department of Pediatric Neurology, Anyang Maternal and Child Health Care Hospital, Anyang Children's Hospital, Anyang, Henan 455002, China.
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van Gemert LA, Leen WG, Draaisma JM, Roeleveld N, Willemsen MA. Head circumference in glucose transporter 1 deficiency syndrome: Normal for individuals, abnormal as a group. Eur J Paediatr Neurol 2022; 38:73-76. [PMID: 35500464 DOI: 10.1016/j.ejpn.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 04/15/2022] [Accepted: 04/19/2022] [Indexed: 10/18/2022]
Abstract
In the literature, microcephaly is considered as part of the classical phenotype of glucose transporter 1 deficiency syndrome (GLUT1DS), and previous cohort studies reported a prevalence of microcephaly of around 50%. In our clinical experience, however, only very few patients with GLUT1DS appear to have microcephaly. Therefore, we conducted an observational study among a large cohort of Dutch patients with GLUT1DS to investigate the prevalence of microcephaly, defined as < 2 standard deviations (SD) below the mean. We analysed the head circumference of 54 patients and found a prevalence of microcephaly at last known measurement of 6.5%. Notably, none of the patients had a head circumference < -3 SD. However, we learned that 75.9% of the patients had a head circumference below 0 SD. This study shows that microcephaly occurs less often than previously thought in patients with GLUT1DS, and that primary or secondary microcephaly does not seem to be a sign for clinicians to suspect GLUT1DS. As a group, however, patients with GLUT1DS seem to have decreased head circumference compared to healthy individuals and as such, our study suggests that early brain development and brain growth may be compromised in GLUT1DS.
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Affiliation(s)
- Loes A van Gemert
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525, GA, Nijmegen, the Netherlands.
| | - Wilhelmina G Leen
- Department of Neurology, Canisius Wilhelmina Hospital, Weg Door Jonkerbos 100, 6532, SZ, Nijmegen, the Netherlands.
| | - Jos M Draaisma
- Department of General Pediatrics, Amalia Children's Hospital, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525, GA, Nijmegen, the Netherlands.
| | - Nel Roeleveld
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525, GA, Nijmegen, the Netherlands.
| | - Michèl A Willemsen
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525, GA, Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behaviour, Montessorilaan 3, 6525, HR, Nijmegen, the Netherlands.
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Good JM, Atallah I, Castro Jimenez M, Benninger D, Kuntzer T, Superti-Furga A, Tran C. NGS-Based Diagnosis of Treatable Neurogenetic Disorders in Adults: Opportunities and Challenges. Genes (Basel) 2021; 12:genes12050695. [PMID: 34066437 PMCID: PMC8148126 DOI: 10.3390/genes12050695] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 12/28/2022] Open
Abstract
The identification of neurological disorders by next-generation sequencing (NGS)-based gene panels has helped clinicians understand the underlying physiopathology, resulting in personalized treatment for some rare diseases. While the phenotype of distinct neurogenetic disorders is generally well-known in childhood, in adulthood, the phenotype can be unspecific and make the standard diagnostic approach more complex. Here we present three unrelated adults with various neurological manifestations who were successfully diagnosed using NGS, allowing for the initiation of potentially life-changing treatments. A 63-year-old woman with progressive cognitive decline, pyramidal signs, and bilateral cataract was treated by chenodeoxycholic acid following the diagnosis of cerebrotendinous xanthomatosis due to a homozygous variant in CYP27A1. A 32-year-old man with adult-onset spastic paraplegia, in whom a variant in ABCD1 confirmed an X-linked adrenoleukodystrophy, was treated with corticoids for adrenal insufficiency. The third patient, a 28-year-old woman with early-onset developmental delay, epilepsy, and movement disorders was treated with a ketogenic diet following the identification of a variant in SLC2A1, confirming a glucose transporter type 1 deficiency syndrome. This case study illustrates the challenges in the timely diagnosis of medically actionable neurogenetic conditions, but also the considerable potential for improving patient health through modern sequencing technologies.
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Affiliation(s)
- Jean-Marc Good
- Division of Genetic Medicine, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (J.-M.G.); (I.A.); (A.S.-F.)
| | - Isis Atallah
- Division of Genetic Medicine, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (J.-M.G.); (I.A.); (A.S.-F.)
| | - Mayte Castro Jimenez
- Division of Neurology, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (M.C.J.); (D.B.); (T.K.)
| | - David Benninger
- Division of Neurology, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (M.C.J.); (D.B.); (T.K.)
| | - Thierry Kuntzer
- Division of Neurology, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (M.C.J.); (D.B.); (T.K.)
| | - Andrea Superti-Furga
- Division of Genetic Medicine, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (J.-M.G.); (I.A.); (A.S.-F.)
| | - Christel Tran
- Division of Genetic Medicine, Lausanne University Hospital (CHUV), 1011 Lausanne, Switzerland; (J.-M.G.); (I.A.); (A.S.-F.)
- Correspondence: ; Tel.: +41-79-556-5325
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Chen L, Wei Z, Chan KWY, Li Y, Suchal K, Bi S, Huang J, Xu X, Wong PC, Lu H, van Zijl PCM, Li T, Xu J. D-Glucose uptake and clearance in the tauopathy Alzheimer's disease mouse brain detected by on-resonance variable delay multiple pulse MRI. J Cereb Blood Flow Metab 2021; 41:1013-1025. [PMID: 32669023 PMCID: PMC8054725 DOI: 10.1177/0271678x20941264] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/29/2020] [Accepted: 06/17/2020] [Indexed: 12/11/2022]
Abstract
In this study, we applied on-resonance variable delay multiple pulse (onVDMP) MRI to study D-glucose uptake in a mouse model of Alzheimer's disease (AD) tauopathy and demonstrated its feasibility in discriminating AD mice from wild-type mice. The D-glucose uptake in the cortex of AD mice (1.70 ± 1.33%) was significantly reduced compared to that of wild-type mice (5.42 ± 0.70%, p = 0.0051). Also, a slower D-glucose uptake rate was found in the cerebrospinal fluid (CSF) of AD mice (0.08 ± 0.01 min-1) compared to their wild-type counterpart (0.56 ± 0.1 min-1, p < 0.001), which suggests the presence of an impaired glucose transporter on both blood-brain and blood-CSF barriers of these AD mice. Clearance of D-glucose was observed in the CSF of wild-type mice but not AD mice, which suggests dysfunction of the glymphatic system in the AD mice. The results in this study indicate that onVDMP MRI could be a cost-effective and widely available method for simultaneously evaluating glucose transporter and glymphatic function of AD. This study also suggests that tau protein affects the D-glucose uptake and glymphatic impairment in AD at a time point preceding neurofibrillary tangle pathology.
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Affiliation(s)
- Lin Chen
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhiliang Wei
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kannie WY Chan
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Yuguo Li
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kapil Suchal
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sheng Bi
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jianpan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Xiang Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Philip C Wong
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter CM van Zijl
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Tong Li
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jiadi Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Yu LF, Zhang YQ, Duan J, Ni Y, Gong XY, Lu ZY, Liao JX, Lu XP, Shi ZN, Lei MF, Zhong JM, Zha J, Zhou SZ. [Clinical characteristics and ketogenic diet therapy of glucose transporter type 1 deficiency syndrome in children: a multicenter clinical study]. Zhonghua Er Ke Za Zhi 2020; 58:881-886. [PMID: 33120458 DOI: 10.3760/cma.j.cn112140-20200822-00819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the clinical characteristics of pediatric glucose transporter type 1 deficiency syndrome (GLUT1 DS), evaluate the efficacy and safety of ketogenic diet therapy (KDT). Methods: Clinical data of 19 children with GLUT1 DS admitted to Children's Hospital of Fudan University, Tianjin Children's Hospital, Shenzhen Children's Hospital, Children's Hospital of Nanjing Medical University and Jiangxi Provincial Children's Hospital between 2015 and 2019 were collected retrospectively. The first onset symptom, main clinical manifestations, cerebrospinal fluid features and genetic testing results of patients were summarized, the efficacy and safety of ketogenic diet treatment were analyzed. Results: Among the 19 cases, 13 were males and 6 females. The age of onset was 11.0 (1.5-45.0) months,the age of diagnosis was 54.0 (2.8-132.0) months. Epilepsy was the first onset symptom of 13 cases. Different forms of tonic-clonic seizures were the most common types of epilepsy (7 cases with generalized tonic-clonic seizures, 5 cases with focal tonic or clonic seizures, 4 cases with generalized tonic seizures). Antiepileptic drugs were effective in 4 cases. Paroxysmal motor dysfunction was present in 12 cases and ataxia was the most common one. All patients had different degrees of psychomotor retardation. Among 17 patients received cerebrospinal fluid examination, cerebrospinal fluid (CSF) glucose level was lower than 2.2 mmol/L and CSF glucose/glycemic index was<0.45 in 16 cases, only 1 case presented normal CSF glucose level (2.3 mmol/L) and normal CSF glucose/glycemic index(0.47). SLC2A1 gene mutations were found in 16 patients, missense, frameshift and nonsense mutations were the common types with 5 cases, 5 cases and 3 cases respectively. All 19 patients were treated with ketogenic diet, which was effective in 18 cases in seizure control, 11 cases in dyskinesia improvement and 18 cases in cognitive function improvement. No serious side effects were reported in any stage of KDT. Conclusions: The diagnosis of GLUT1 DS is often late. It is necessary to improve the early recognition of the disease and perform CSF glucose detection and genetic testing as early as possible. The KDT is an effective and safe treatment for GLUT1 DS, but a small number of patients have not response to diet therapy.
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Affiliation(s)
- L F Yu
- Department of Neurology, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Y Q Zhang
- Department of Neurology, Tianjin Children's Hospital, Tianjin 300400, China
| | - J Duan
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen 518038, China
| | - Y Ni
- Department of Neurology, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - X Y Gong
- Department of Nutrition, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Z Y Lu
- Department of Nutrition, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - J X Liao
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen 518038, China
| | - X P Lu
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
| | - Z N Shi
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
| | - M F Lei
- Department of Neurology, Tianjin Children's Hospital, Tianjin 300400, China
| | - J M Zhong
- Department of Neurology, Jiangxi Provincial Children's Hospital, Nanchang 330006, China
| | - J Zha
- Department of Neurology, Jiangxi Provincial Children's Hospital, Nanchang 330006, China
| | - S Z Zhou
- Department of Neurology, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
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Ari C, Murdun C, Goldhagen C, Koutnik AP, Bharwani SR, Diamond DM, Kindy M, D’Agostino DP, Kovacs Z. Exogenous Ketone Supplements Improved Motor Performance in Preclinical Rodent Models. Nutrients 2020; 12:nu12082459. [PMID: 32824223 PMCID: PMC7468837 DOI: 10.3390/nu12082459] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/05/2020] [Accepted: 08/13/2020] [Indexed: 12/14/2022] Open
Abstract
Nutritional ketosis has been proven effective for neurometabolic conditions and disorders linked to metabolic dysregulation. While inducing nutritional ketosis, ketogenic diet (KD) can improve motor performance in the context of certain disease states, but it is unknown whether exogenous ketone supplements—alternatives to KDs—may have similar effects. Therefore, we investigated the effect of ketone supplements on motor performance, using accelerating rotarod test and on postexercise blood glucose and R-beta-hydroxybutyrate (R-βHB) levels in rodent models with and without pathology. The effect of KD, butanediol (BD), ketone-ester (KE), ketone-salt (KS), and their combination (KE + KS: KEKS) or mixtures with medium chain triglyceride (MCT) (KE + MCT: KEMCT; KS + MCT: KSMCT) was tested in Sprague-Dawley (SPD) and WAG/Rij (WR) rats and in GLUT-1 Deficiency Syndrome (G1D) mice. Motor performance was enhanced by KEMCT acutely, KE and KS subchronically in SPD rats, by KEKS and KEMCT groups in WR rats, and by KE chronically in G1D mice. We demonstrated that exogenous ketone supplementation improved motor performance to various degrees in rodent models, while effectively elevated R-βHB and in some cases offsets postexercise blood glucose elevations. Our results suggest that improvement of motor performance varies depending on the strain of rodents, specific ketone formulation, age, and exposure frequency.
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Affiliation(s)
- Csilla Ari
- Department of Psychology, Behavioral Neuroscience Research Laboratory, University of South Florida, Tampa, FL 33620, USA; (S.R.B.); (D.M.D.)
- Ketone Technologies, Tampa, FL 33612, USA;
- Correspondence: or ; Tel.: +1-813-240-9925
| | - Cem Murdun
- Department of Molecular Pharmacology and Physiology, Laboratory of Metabolic Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (C.G.); (A.P.K.)
| | - Craig Goldhagen
- Department of Molecular Pharmacology and Physiology, Laboratory of Metabolic Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (C.G.); (A.P.K.)
| | - Andrew P. Koutnik
- Department of Molecular Pharmacology and Physiology, Laboratory of Metabolic Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (C.G.); (A.P.K.)
- Institute for Human and Machine Cognition, Ocala, FL 34471, USA
| | - Sahil R. Bharwani
- Department of Psychology, Behavioral Neuroscience Research Laboratory, University of South Florida, Tampa, FL 33620, USA; (S.R.B.); (D.M.D.)
| | - David M. Diamond
- Department of Psychology, Behavioral Neuroscience Research Laboratory, University of South Florida, Tampa, FL 33620, USA; (S.R.B.); (D.M.D.)
- Department of Molecular Pharmacology and Physiology, Laboratory of Metabolic Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (C.G.); (A.P.K.)
| | - Mark Kindy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL 33612, USA;
- James A. Haley VA Medical Center, Tampa, FL 33612, USA
- Shriners Hospital for Children, Tampa, FL 33612, USA
| | - Dominic P. D’Agostino
- Ketone Technologies, Tampa, FL 33612, USA;
- Department of Molecular Pharmacology and Physiology, Laboratory of Metabolic Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (C.G.); (A.P.K.)
- Institute for Human and Machine Cognition, Ocala, FL 34471, USA
| | - Zsolt Kovacs
- Savaria Department of Biology, ELTE Eötvös Loránd University, Savaria University Centre, Károlyi Gáspár tér 4., 9700 Szombathely, Hungary;
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11
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Abstract
Glucose transport is intimately linked to red blood cell physiology. Glucose is the unique energy source for these cells, and defects in glucose metabolism or transport activity are associated with impaired red blood cell morphology and deformability leading to reduced lifespan. In vertebrate erythrocytes, glucose transport is mediated by GLUT1 (in humans) or GLUT4 transporters. These proteins also account for dehydroascorbic acid (DHA) transport through erythrocyte membrane. The peculiarities of glucose transporters and the red blood cell pathologies involving GLUT1 are summarized in the present review.
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Affiliation(s)
- Hélène Guizouarn
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, 28 av. Valrose, 06100, Nice, France.
| | - Benoit Allegrini
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, 28 av. Valrose, 06100, Nice, France
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12
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Narváez C, Lacaux P, Cortés C, Manterola C, Carrasco X. Phenotypic variability of GLUT1 deficiency: When is necessary to suspect? Rev Chil Pediatr 2020; 91:260-264. [PMID: 32730547 DOI: 10.32641/rchped.v91i2.1185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 09/22/2019] [Indexed: 06/11/2023]
Abstract
INTRODUCTION Glucose Transporter Type 1 Deficiency Syndrome (GLUT1-DS) is caused by the SLC2A1 gene muta tion, which encodes the glucose transporter proteins to the brain Neurological manifestations occur in three main domains: seizures, abnormal movements, and cognitive disorders. The diagnosis is presumed upon the finding of low CSF glucose and confirmed by the gene molecular analysis. Ac curate diagnosis is important because it has a specific treatment, which is ketogenic diet. OBJECTIVE To analyze two SD-GLUT1 pediatric patients with unusual phenotype. CLINICAL CASE We present the case of two siblings who presented absence seizures and a paroxysmal movement disorder. Both patients were studied, finding low CSF glucose. The diagnosis of GLUT1-DS was confirmed with molecular analysis. Specific treatment with ketogenic diet achieved good response in both cases. Con clusions: We present their peculiar clinical characteristics that allowed us to suspect this wide phe notypic spectrum. Correct and timely diagnosis and treatment can significantly improve the quality of life of those affected.
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Affiliation(s)
- Carolina Narváez
- Hospital Dr. Luis Calvo Mackenna, Facultad de Medicina, Universidad de Chile, Chile
| | - Patricio Lacaux
- Hospital Dr. Luis Calvo Mackenna, Facultad de Medicina, Universidad de Chile, Chile
| | - Camila Cortés
- Hospital Dr. Luis Calvo Mackenna, Facultad de Medicina, Universidad de Chile, Chile
| | - Carla Manterola
- Hospital Dr. Luis Calvo Mackenna, Facultad de Medicina, Universidad de Chile, Chile
| | - Ximena Carrasco
- Hospital Dr. Luis Calvo Mackenna, Facultad de Medicina, Universidad de Chile, Chile
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13
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Schwantje M, Verhagen LM, van Hasselt PM, Fuchs SA. Glucose transporter type 1 deficiency syndrome and the ketogenic diet. J Inherit Metab Dis 2020; 43:216-222. [PMID: 31605543 PMCID: PMC7078900 DOI: 10.1002/jimd.12175] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 08/28/2019] [Accepted: 09/20/2019] [Indexed: 01/11/2023]
Abstract
Glucose transporter type 1 deficiency syndrome (GLUT1DS) is characterised by deficient glucose transport over the blood-brain barrier and reduced glucose availability in the brain. This causes epilepsy, movement disorders, and cognitive impairment. Treatment with ketogenic diet provides ketones as alternative energy source. However, not all GLUT1DS patients are on dietary treatment (worldwide registry: 77/181 [43%] of patients). The current 25-year experience allows evaluation of effects and tolerability of dietary treatment for GLUT1DS. To this end, literature was searched up to January 2019 for individual case reports and series reporting (side) effects of dietary treatment for GLUT1DS. Upon aggregation of data for analysis, we identified 270 GLUT1DS patients with dietary treatment with a mean follow-up of 53 months. Epilepsy improved for 83% of 230 patients and remained unchanged for 17%, movement disorders improved for 82% of 127 patients and remained unchanged for 17%, and cognition improved for 59% of 58 patients and remained stable for 40%. Effects on epilepsy were seen within days/weeks and were most pronounced in patients with early treatment initiation. Effects on movement disorders were noticed within months and were strongest in patients with higher cerebrospinal fluid-to-blood glucose ratio. Although side effects were minimal, 18% of 270 patients reported poor compliance. In individual patients, symptoms deteriorated upon low ketosis, poor compliance, or treatment discontinuation. Based on the good tolerability and strong favourable effect of dietary treatment on GLUT1DS symptoms, we advocate dietary treatment in all GLUT1DS patients and prompt diagnosis or screening to allow early treatment.
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Affiliation(s)
- Marit Schwantje
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Lilly M. Verhagen
- Department of Infectious diseases and Immunology, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Peter M. van Hasselt
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Sabine A. Fuchs
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
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14
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Raja M, Kinne RKH. Mechanistic Insights into Protein Stability and Self-aggregation in GLUT1 Genetic Variants Causing GLUT1-Deficiency Syndrome. J Membr Biol 2020; 253:87-99. [PMID: 32025761 PMCID: PMC7150661 DOI: 10.1007/s00232-020-00108-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/14/2020] [Indexed: 12/23/2022]
Abstract
Human sodium-independent glucose cotransporter 1 (hGLUT1) has been studied for its tetramerization and multimerization at the cell surface. Homozygous or compound heterozygous mutations in hGLUT1 elicit GLUT1-deficiency syndrome (GLUT1-DS), a metabolic disorder, which results in impaired glucose transport into the brain. The reduced cell surface expression or loss of function have been shown for some GLUT1 mutants. However, the mechanism by which deleterious mutations affect protein structure, conformational stability and GLUT1 oligomerization is not known and require investigation. In this review, we combined previous knowledge of GLUT1 mutations with hGLUT1 crystal structure to analyze native interactions and several natural single-point mutations. The modeling of native hGLUT1 structure confirmed the roles of native residues in forming a range of side-chain interactions. Interestingly, the modeled mutants pointed to the formation of a variety of non-native novel interactions, altering interaction networks and potentially eliciting protein misfolding. Self-aggregation of the last part of hGLUT1 was predicted using protein aggregation prediction tool. Furthermore, an increase in aggregation potential in the aggregation-prone regions was estimated for several mutants suggesting increased aggregation of misfolded protein. Protein stability change analysis predicted that GLUT1 mutant proteins are unstable. Combining GLUT1 oligomerization behavior with our modeling, aggregation prediction, and protein stability analyses, this work provides state-of-the-art view of GLUT1 genetic mutations that could destabilize native interactions, generate novel interactions, trigger protein misfolding, and enhance protein aggregation in a disease state.
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Affiliation(s)
- Mobeen Raja
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
- Algonquin College, 1385 Woodroffe Avenue, Ottawa, ON K2G 1V8 Canada
| | - Rolf K. H. Kinne
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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15
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Kim H, Lee JS, Lee Y, Kim SY, Lim BC, Kim KJ, Choi M, Chae JH. Diagnostic Challenges Associated with GLUT1 Deficiency: Phenotypic Variabilities and Evolving Clinical Features. Yonsei Med J 2019; 60:1209-1215. [PMID: 31769253 PMCID: PMC6881708 DOI: 10.3349/ymj.2019.60.12.1209] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/08/2019] [Accepted: 11/05/2019] [Indexed: 01/18/2023] Open
Abstract
GLUT1 deficiency is a rare neurometabolic disorder that can be effectively treated with ketogenic diet. However, this condition is underdiagnosed due to its nonspecific, overlapping, and evolving symptoms with age. We retrospectively reviewed the clinical course of nine patients diagnosed with GLUT1 deficiency, based on SLC2A1 mutations and/or glucose concentration in cerebrospinal fluid. The patients included eight boys and one girl who initially presented with seizures (44%, 4/9) or delayed development (44%, 4/9) before 2 years of age, except for one patient who presented with apnea as a neonate. Over the clinical course, all of the children developed seizures of the mixed type, including absence seizures and generalized tonic-clonic seizures. About half (56%, 5/9) showed movement disorders such as ataxia, dystonia, or dyskinesia. We observed an evolution of phenotype over time, although this was not uniform across all patients. Only one child had microcephaly. In five patients, ketogenic diet was effective in reducing seizures and movement symptoms, and the patients exhibited subjective improvement in cognitive function. Diagnosing GLUT1 deficiency can be challenging due to the phenotypic variability and evolution. A high index of clinical suspicion in pediatric and even older patients with epilepsy or movement disorders is key to the early diagnosis and treatment, which can improve the patient's quality of life.
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Affiliation(s)
- Hyuna Kim
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Sook Lee
- Department of Pediatrics, Department of Genome Medicine and Science, Gil Medical Center, Gachon University College of Medicine, Incheon, Korea
| | - Youngha Lee
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Soo Yeon Kim
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Byung Chan Lim
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ki Joong Kim
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Murim Choi
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea.
| | - Jong Hee Chae
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
- Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea.
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16
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Ari C, Murdun C, Koutnik AP, Goldhagen CR, Rogers C, Park C, Bharwani S, Diamond DM, Kindy MS, D’Agostino DP, Kovács Z. Exogenous Ketones Lower Blood Glucose Level in Rested and Exercised Rodent Models. Nutrients 2019; 11:E2330. [PMID: 31581549 PMCID: PMC6835632 DOI: 10.3390/nu11102330] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/30/2019] [Accepted: 09/17/2019] [Indexed: 01/08/2023] Open
Abstract
Diseases involving inflammation and oxidative stress can be exacerbated by high blood glucose levels. Due to tight metabolic regulation, safely reducing blood glucose can prove difficult. The ketogenic diet (KD) reduces absolute glucose and insulin, while increasing fatty acid oxidation, ketogenesis, and circulating levels of β-hydroxybutyrate (βHB), acetoacetate (AcAc), and acetone. Compliance to KD can be difficult, so alternative therapies that help reduce glucose levels are needed. Exogenous ketones provide an alternative method to elevate blood ketone levels without strict dietary requirements. In this study, we tested the changes in blood glucose and ketone (βHB) levels in response to acute, sub-chronic, and chronic administration of various ketogenic compounds in either a post-exercise or rested state. WAG/Rij (WR) rats, a rodent model of human absence epilepsy, GLUT1 deficiency syndrome mice (GLUT1D), and wild type Sprague Dawley rats (SPD) were assessed. Non-pathological animals were also assessed across different age ranges. Experimental groups included KD, standard diet (SD) supplemented with water (Control, C) or with exogenous ketones: 1, 3-butanediol (BD), βHB mineral salt (KS), KS with medium chain triglyceride/MCT (KSMCT), BD acetoacetate diester (KE), KE with MCT (KEMCT), and KE with KS (KEKS). In rested WR rats, the KE, KS, KSMCT groups had lower blood glucose level after 1 h of treatment, and in KE and KSMCT groups after 24 h. After exercise, the KE, KSMCT, KEKS, and KEMCT groups had lowered glucose levels after 1 h, and in the KEKS and KEMCT groups after 7 days, compared to control. In GLUT1D mice without exercise, only KE resulted in significantly lower glucose levels at week 2 and week 6 during a 10 weeks long chronic feeding study. In 4-month and 1-year-old SPD rats in the post-exercise trials, blood glucose was significantly lower in KD and KE, and in KEMCT groups, respectively. After seven days, the KSMCT group had the most significantly reduced blood glucose levels, compared to control. These results indicate that exogenous ketones were efficacious in reducing blood glucose levels within and outside the context of exercise in various rodent models of different ages, with and without pathology.
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MESH Headings
- 3-Hydroxybutyric Acid/pharmacology
- Acetoacetates/pharmacology
- Animals
- Biomarkers
- Blood Glucose/drug effects
- Blood Glucose/metabolism
- Butylene Glycols/pharmacology
- Carbohydrate Metabolism, Inborn Errors/blood
- Carbohydrate Metabolism, Inborn Errors/genetics
- Carbohydrate Metabolism, Inborn Errors/physiopathology
- Carbohydrate Metabolism, Inborn Errors/therapy
- Diet, Ketogenic
- Dietary Supplements
- Disease Models, Animal
- Down-Regulation
- Epilepsy, Absence/blood
- Epilepsy, Absence/genetics
- Epilepsy, Absence/physiopathology
- Epilepsy, Absence/therapy
- Glucose Transporter Type 1/deficiency
- Glucose Transporter Type 1/genetics
- Male
- Mice, Knockout
- Monosaccharide Transport Proteins/blood
- Monosaccharide Transport Proteins/deficiency
- Monosaccharide Transport Proteins/genetics
- Physical Exertion
- Rats, Sprague-Dawley
- Rest
- Time Factors
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Affiliation(s)
- Csilla Ari
- Department of Psychology, University of South Florida, Tampa, FL 33620, USA; (C.P.); (S.B.); (D.M.D.)
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Cem Murdun
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Andrew P. Koutnik
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Craig R. Goldhagen
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Christopher Rogers
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Collin Park
- Department of Psychology, University of South Florida, Tampa, FL 33620, USA; (C.P.); (S.B.); (D.M.D.)
| | - Sahil Bharwani
- Department of Psychology, University of South Florida, Tampa, FL 33620, USA; (C.P.); (S.B.); (D.M.D.)
| | - David M. Diamond
- Department of Psychology, University of South Florida, Tampa, FL 33620, USA; (C.P.); (S.B.); (D.M.D.)
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
| | - Mark S. Kindy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL 33620, USA;
- James A. Haley VA Medical Center, Tampa, FL 33612, USA
- Shriners Hospital for Children, Tampa, FL 33612, USA
| | - Dominic P. D’Agostino
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (C.M.); (A.P.K.); (C.R.G.); (C.R.); (D.P.D.)
- Institute for Human and Machine Cognition, Ocala, FL 33471, USA
| | - Zsolt Kovács
- Savaria Department of Biology, ELTE Eötvös Loránd University, Savaria University Centre, Károlyi Gáspár tér 4., 9700 Szombathely, Hungary
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17
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De Amicis R, Leone A, Lessa C, Foppiani A, Ravella S, Ravasenghi S, Trentani C, Ferraris C, Veggiotti P, De Giorgis V, Tagliabue A, Battezzati A, Bertoli S. Long-Term Effects of a Classic Ketogenic Diet on Ghrelin and Leptin Concentration: A 12-Month Prospective Study in a Cohort of Italian Children and Adults with GLUT1-Deficiency Syndrome and Drug Resistant Epilepsy. Nutrients 2019; 11:nu11081716. [PMID: 31349661 PMCID: PMC6722776 DOI: 10.3390/nu11081716] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/17/2019] [Accepted: 07/23/2019] [Indexed: 02/07/2023] Open
Abstract
The classical ketogenic diet (cKD) is an isocaloric, high fat, very low-carbohydrate diet that induces ketosis, strongly influencing leptin and ghrelin regulation. However, not enough is known about the impact of a long-term cKD. This study evaluated the effects of a 12-month cKD on ghrelin and leptin concentrations in children, adolescents and adults affected by the GLUT1-Deficiency Syndrome or drug resistant epilepsy (DRE). We also investigated the relationship between the nutritional status, body composition and ghrelin and leptin variations. We carried out a longitudinal study on 30 patients: Twenty-five children and adolescents (15 females, 8 ± 4 years), and five adults (two females, 34 ± 16 years). After 12-monoths cKD, there were no significant changes in ghrelin and leptin, or in the nutritional status, body fat, glucose and lipid profiles. However, a slight height z-score reduction (from −0.603 ± 1.178 to −0.953 ± 1.354, p ≤ 0.001) and a drop in fasting insulin occurred. We found no correlations between ghrelin changes and nutritional status and body composition, whereas leptin changes correlated positively with variations in the weight z-score and body fat (ρ = 0.4534, p = 0.0341; ρ = 0.5901, p = 0.0135; respectively). These results suggest that a long-term cKD does not change ghrelin and leptin concentrations independently of age and neurological condition.
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Affiliation(s)
- Ramona De Amicis
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy.
| | - Alessandro Leone
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Chiara Lessa
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Andrea Foppiani
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Simone Ravella
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Stefano Ravasenghi
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Claudia Trentani
- Human Nutrition and Eating Disorder Research Center, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy
| | - Cinzia Ferraris
- Human Nutrition and Eating Disorder Research Center, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy
| | - Pierangelo Veggiotti
- Pediatric Neurology Unit, Vittore Buzzi Hospital, Via Lodovico Castelvetro 32, 20154 Milan, Italy
- Biomedical and Clinical Sciences Department, Luigi Sacco Hospital, University of Milan, via G. B. Grassi 74, 20157 Milan, Italy
| | - Valentina De Giorgis
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy
| | - Anna Tagliabue
- Human Nutrition and Eating Disorder Research Center, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy
| | - Alberto Battezzati
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
| | - Simona Bertoli
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Sandro Botticelli 21, 20133 Milan, Italy
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18
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Bekker YAC, Lambrechts DA, Verhoeven JS, van Boxtel J, Troost C, Kamsteeg EJ, Willemsen MA, Braakman HMH. Failure of ketogenic diet therapy in GLUT1 deficiency syndrome. Eur J Paediatr Neurol 2019; 23:404-409. [PMID: 30885501 DOI: 10.1016/j.ejpn.2019.02.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/20/2019] [Accepted: 02/24/2019] [Indexed: 11/16/2022]
Abstract
PURPOSE Epilepsy in GLUT1 deficiency syndrome is generally drug-resistant; ketogenic diet (KD) therapy is the mainstay of therapy, as production of ketones provides the brain with an alternative energy source, bypassing the defect in GLUT1. Failure of KD therapy and risk factors for failure have been sparsely published. METHODS We performed a retrospective study of GLUT1DS patients with refractory epilepsy failing on KD therapy, to identify their clinical characteristics. RESULTS Failure of the ketogenic diet was due to KD inefficacy (poor effect despite adequate ketosis), as well as intolerance and an inability to attain ketosis. Our cohort of seven patients in whom KD therapy failed stood out for their advanced age at seizure onset, i.e. almost 4 years vs 8 months in large series, female sex, as well as their advanced age at diagnosis and initiation of KD therapy. EEG recordings during KD therapy can aid in the assessment of effectiveness of the KD therapy. CONCLUSIONS GLUT1DS is generally described as a treatable disorder and existing case series do not provide details of treatment failure. In select patients with GLUT1DS, KD therapy fails, rendering GLUT1DS an essentially untreatable disorder. Failure of the ketogenic diet was due to KD inefficacy (poor effect despite adequate ketosis), as well as intolerance and an inability to attain ketosis. Failure to reduce seizure frequency with deterioration of the EEG findings should lead to consideration of cessation of KD therapy.
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Affiliation(s)
- Yvonne A C Bekker
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center & Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
| | - Danielle A Lambrechts
- Department of Neurology, Academic Center for Epileptology, Kempenhaeghe and Maastricht University Medical Centre, Heeze, the Netherlands
| | - Judith S Verhoeven
- Department of Neurology, Academic Center for Epileptology, Kempenhaeghe and Maastricht University Medical Centre, Heeze, the Netherlands
| | - Jessy van Boxtel
- Department of Dietetics, Academic Center for Epileptology, Kempenhaeghe and Maastricht University Medical Centre, Heeze, the Netherlands
| | - Caroline Troost
- Department of Dietetics, Academic Center for Epileptology, Kempenhaeghe and Maastricht University Medical Centre, Heeze, the Netherlands
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Michèl A Willemsen
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center & Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
| | - Hilde M H Braakman
- Department of Neurology, Academic Center for Epileptology, Kempenhaeghe and Maastricht University Medical Centre, Heeze, the Netherlands.
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19
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Raggi F, Pissavino AL, Resaz R, Segalerba D, Puglisi A, Vanni C, Antonini F, Del Zotto G, Gamberucci A, Marcolongo P, Bosco MC, Grillo F, Mastracci L, Eva A. Development and characterization of an inducible mouse model for glycogen storage disease type Ib. J Inherit Metab Dis 2018; 41:1015-1025. [PMID: 29967951 DOI: 10.1007/s10545-018-0211-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/23/2018] [Accepted: 05/30/2018] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND AIMS Glycogen storage disease type Ib (GSD1b) is a rare metabolic and immune disorder caused by a deficiency in the glucose-6-phosphate transporter (G6PT) and characterized by impaired glucose homeostasis, myeloid dysfunction, and long-term risk of hepatocellular adenomas. Despite maximal therapy, based on a strict diet and on granulocyte colony-stimulating factor treatment, long-term severe complications still develop. Understanding the pathophysiology of GSD1b is a prerequisite to develop new therapeutic strategies and depends on the availability of animal models. The G6PT-KO mouse mimics the human disease but is very fragile and rarely survives weaning. We generated a conditional G6PT-deficient mouse as an alternative model for studying the long-term pathophysiology of the disease. We utilized this conditional mouse to develop an inducible G6PT-KO model to allow temporally regulated G6PT deletion by the administration of tamoxifen (TM). METHODS We generated a conditional G6PT-deficient mouse utilizing the CRElox strategy. Histology, histochemistry, and phenotype analyses were performed at different times after TM-induced G6PT inactivation. Neutrophils and monocytes were isolated and analyzed for functional activity with standard techniques. RESULTS The G6PT-inducible KO mice display the expected disturbances of G6P metabolism and myeloid dysfunctions of the human disorder, even though with a milder intensity. CONCLUSIONS TM-induced inactivation of G6PT in these mice leads to a phenotype which mimics that of human GSD1b patients. The conditional mice we have generated represent an excellent tool to study the tissue-specific role of the G6PT gene and the mechanism of long-term complications in GSD1b.
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Affiliation(s)
- Federica Raggi
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Anna Livia Pissavino
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Roberta Resaz
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Daniela Segalerba
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Andrea Puglisi
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Cristina Vanni
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Francesca Antonini
- Core Facilities Laboratory, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Genoa, Italy
| | - Genny Del Zotto
- Core Facilities Laboratory, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Genoa, Italy
| | - Alessandra Gamberucci
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Paola Marcolongo
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Maria Carla Bosco
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy
| | - Federica Grillo
- Pathology Unit, Department of Surgical Sciences and Integrated Diagnostics, University of Genova, Genoa, Italy
- IRCCS AOU San Martino IST Genova, Genoa, Italy
| | - Luca Mastracci
- Pathology Unit, Department of Surgical Sciences and Integrated Diagnostics, University of Genova, Genoa, Italy
- IRCCS AOU San Martino IST Genova, Genoa, Italy
| | - Alessandra Eva
- Laboratory of Molecular Biology, Department of Translational Research, Laboratory Medicine, Diagnosis and Services, Istituto Giannina Gaslini, Largo Gaslini 5, 16147, Genoa, Italy.
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20
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Abstract
The authors describe a 3-year-old female, diagnosed with GLUT1 deficiency Syndrome, with a previously unreported mutation in exon 7 of the SLC2A1 gene: c.968_972 + 3del P. (Val323Alafs*53), characterized by a classic phenotypic of acquired microcephaly, developmental delay, ataxia, spasticity, and epilepsy. Ketogenic diet was started at the age of 30 months with epilepsy improvement. She presented paroxysmal ocular movements in the first 12 months of life, recently defined as "aberrant gaze saccades", that are present in the early phase of visual system development, being one of the first disease signs, but easily disregarded. Recognizing these particular ocular movements would allow an early diagnosis, followed by ketogenic diet implementation, improving significantly the prognosis and the neurological development of those children.
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Affiliation(s)
- Sofia Reis
- Serviço de Pediatria, Centro Hospitalar Tondela-Viseu, EPE, Av. Rei D. Duarte, 3504-509, Viseu, Portugal.
| | | | - Raquel Machado
- Hospital Vila Franca de Xira, Vila Franca de Xira, Portugal
| | - José Paulo Monteiro
- Torrado da Silva Development Child Center, Hospital Garcia de Orta, Almada, Portugal
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21
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van Kan KEM, Panis B. [Exercise and fasting induced movement disorder in children: think of the GLUT1 deficiency syndrome]. Ned Tijdschr Geneeskd 2018; 162:D2607. [PMID: 30040286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
BACKGROUND Glucose transporter type 1 (GLUT1) enables glucose to pass through the blood-brain barrier. A hereditary deficiency of this protein may lead to clinical symptoms when blood glucose levels are decreasing. CASE DESCRIPTION A 7-year-old girl with therapy-resistant childhood absence epilepsy presented with an exercise and fasting induced dystonic and atactic movement pattern. The movement pattern disappears postprandial. Based on a reduced glucose in the liquor, and also a reduced liquor glucose/serum glucose ratio, the diagnosis of GLUT1 deficiency syndrome was considered. Through genetic diagnostics a mutation of the SLC2A1 gene was identified, thereby confirming the initial diagnosis. The patient was referred to a tertiary centre for advice on following a ketogenic diet. After initiation of this treatment she no longer experienced absence epilepsy or paroxysmal dyskinesia episodes. CONCLUSION GLUT1 deficiency syndrome is a relatively underdiagnosed disease. The recommended therapy is adherence to a ketogenic diet. With this diet the symptoms are treated, yet at the same time the further development of the brain is stimulated.
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Affiliation(s)
- Kim E M van Kan
- Zuyderland Medisch Centrum, afd. Kindergeneeskunde, locaties Sittard-Geleen en Heerlen
- Contact: K.E.M. van Kan
| | - Bianca Panis
- Zuyderland Medisch Centrum, afd. Kindergeneeskunde, locaties Sittard-Geleen en Heerlen
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22
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Mayorga L, Gamboni B, Mampel A, Roqué M. A frame-shift deletion in the PURA gene associates with a new clinical finding: Hypoglycorrhachia. Is GLUT1 a new PURA target? Mol Genet Metab 2018; 123:331-336. [PMID: 29307761 DOI: 10.1016/j.ymgme.2017.12.436] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/29/2017] [Accepted: 12/30/2017] [Indexed: 12/24/2022]
Abstract
PURA is a DNA/RNA-binding protein known to have an important role as a transcriptional and translational regulator. Mutations in the PURA gene have been documented to cause mainly a neurologic phenotype including hypotonia, epilepsy, development delay and respiratory alterations. We report here a patient with a frame-shift deletion in the PURA gene that apart from the classical PURA deficiency phenotype had marked hypoglycorrhachia, overlapping the clinical findings with a GLUT1 deficiency syndrome. SLC2A1 (GLUT1) mutations were discarded, so we hypothesized that GLUT1 could be downregulated in this PURA deficient scenario. We confirmed reduced GLUT1 expression in the patient's peripheral blood cells compared to controls predicting that this could also be happening in the blood-brain barrier and in this way explain the hypoglycorrhachia. Based on PURA's known functions as a transcriptional and translational regulator, we propose GLUT1 as a new PURA target. Further in vitro and in vivo studies are needed to confirm this and to uncover the underlying molecular mechanisms.
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Affiliation(s)
- Lía Mayorga
- Instituto de Histología y Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.
| | - Beatriz Gamboni
- Instituto de Neurología Infanto Juvenil (Neuroinfan), Mendoza, Argentina
| | - Alejandra Mampel
- Instituto de Genética, Hospital Universitario, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - María Roqué
- Instituto de Histología y Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina
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23
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Nakamura S, Osaka H, Muramatsu S, Aoki S, Jimbo EF, Yamagata T. Mutational and functional analysis of Glucose transporter I deficiency syndrome. Mol Genet Metab 2015; 116:157-62. [PMID: 26304067 DOI: 10.1016/j.ymgme.2015.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 08/09/2015] [Accepted: 08/09/2015] [Indexed: 01/11/2023]
Abstract
OBJECTIVE We investigated a correlation between a mutation in the SLC2A1 gene and functional disorders in Glucose transporter I deficiency syndrome (GLUT1DS). METHODS We performed direct sequence analysis of SLC2A1 in a severe GLUT1DS patient and identified a novel frame shift mutation, c.906_907insG, p.V303fs. We created a plasmid vector carrying the c.906_907insG mutation, as well as A405D or R333W in the SLC2A1, which are found in patients with mild and moderate GLUT1DS severity, respectively. We transiently expressed these mutants and wild type SLC2A1 plasmids in a human embryonic kidney cell line (HEK293), and performed immunoblotting, immunofluorescence, and enzymatic photometric 2-deoxyglucose (2DG) uptake assays. RESULTS GLUT1 was not detected after transient expression of the SLC2A1 plasmid carrying c.906_907insG by either immunoblotting or immunofluorescence. The degree of glucose transport reduction as determined by enzymatic photometric 2DG assay uptake correlated with disease severity. CONCLUSIONS Enzymatic photometric 2DG uptake study appears to be a suitable functional assay to predict the effect of SLC2A1 mutations on GLUT1 transport.
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Affiliation(s)
- Sachie Nakamura
- Department of Pediatrics, Jichi Medical University, Tochigi, Japan
| | - Hitoshi Osaka
- Department of Pediatrics, Jichi Medical University, Tochigi, Japan.
| | - Shinichi Muramatsu
- Division of Neurology, Jichi Medical University, Tochigi, Japan; Center for Gene and Cell Therapy, The Institute of Medical Science, The University of Tokyo, Japan
| | - Shiho Aoki
- Department of Pediatrics, Jichi Medical University, Tochigi, Japan
| | - Eriko F Jimbo
- Department of Pediatrics, Jichi Medical University, Tochigi, Japan
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24
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Gowda VK, Sheshu S. Intermittent Ataxia with Early Onset Absence Epilepsy in Glucose Transporter Type 1 Deficiency Syndrome. Indian Pediatr 2015; 52:997. [PMID: 26615362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Vykuntaraju K Gowda
- Bangalore Child Neurology and Rehabilitation Center, Vijayanagar, Bengaluru, India
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25
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Dörre K, Olczak M, Wada Y, Sosicka P, Grüneberg M, Reunert J, Kurlemann G, Fiedler B, Biskup S, Hörtnagel K, Rust S, Marquardt T. A new case of UDP-galactose transporter deficiency (SLC35A2-CDG): molecular basis, clinical phenotype, and therapeutic approach. J Inherit Metab Dis 2015; 38:931-40. [PMID: 25778940 DOI: 10.1007/s10545-015-9828-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 02/10/2015] [Accepted: 02/13/2015] [Indexed: 10/23/2022]
Abstract
Congenital disorders of glycosylation (CDG) are a group of hereditary metabolic diseases characterized by abnormal glycosylation of proteins and lipids. Often, multisystem disorders with central nervous system involvement and a large variety of clinical symptoms occur. The main characteristics are developmental delay, seizures, and ataxia. In this paper we report the clinical and biochemical characteristics of a 5-year-old girl with a defective galactosylation of N-glycans, resulting in developmental delay, muscular hypotonia, epileptic seizures, inverted nipples, and visual impairment. Next generation sequencing revealed a de novo mutation (c.797G > T, p.G266V) in the X-chromosomal gene SLC35A2 (solute carrier family 35, UDP-galactose transporter, member A2; MIM 300896). While this mutation was found heterozygous, random X-inactivation of the normal allele will lead to loss of normal SLC35A2 activity in respective cells. The functional relevance of the mutation was demonstrated by complementation of UGT-deficient MDCK-RCA(r) and CHO-Lec8 cells by normal UGT-expression construct but not by the mutant version. The effect of dietary galactose supplementation on glycosylation was investigated, showing a nearly complete normalization of transferrin glycosylation.
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Affiliation(s)
- K Dörre
- Universitätsklinikum Münster, Klinik für Kinder-und Jugendmedizin, Albert-Schweitzer-Campus 1, 48149, Muenster, Germany
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26
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Abstract
In this issue, Lee et al. (2015) show that PKC directly phosphorylates the glucose transporter Glut1, in order to promote glucose uptake in response to growth factor signaling.
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Affiliation(s)
- Peter J Siska
- Department of Pharmacology and Cancer Biology, Department of Immunology, Duke Molecular Physiology Institute, Duke University, Durham, NC 27710, USA
| | - Jeffrey C Rathmell
- Department of Pharmacology and Cancer Biology, Department of Immunology, Duke Molecular Physiology Institute, Duke University, Durham, NC 27710, USA.
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27
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Sasaki M, Sugie H. [Joint researches supported by Japanese Society of Child Neurology (JSCN) the committee of joint researches]. No To Hattatsu 2014; 46:210-212. [PMID: 24902341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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28
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Imai K, Ishihara E, Ikeda H. [Dietary therapy of epilepsy]. Nihon Rinsho 2014; 72:875-880. [PMID: 24912289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Reappraisal of ketogenic diets (KD) were delayed in Japan compared to USA and Korea. The reasons are unknown, but possible explanations are (1) Japanese food culture prefers rice and less fat and (2) ACTH therapy is preferred for West syndrome in Japan. Since Japanese child neurologists were surprised at dramatic effects on glucose transporter 1 deficiency syndrome (Glut-1DS) in 2003, KD have been slowly accepted for treatment of epilepsy in Japan. New generation KD including modified Atkins diet (mAD) are preferred to classical KD. KD can be causal therapy in Glut-1DS and some of mitochondrial disorders, though anti-epileptic drugs are symptomatic therapy. KD can alleviate intractable seizures in epilepsies with brain malformation in addition to West syndrome and Dravet syndrome, etc. KD may work for brain tumor, cancer, neurodegenerative disorders including Alzheimer's disease. C7-8 triglycerides or fatty acid esters are under development as medicines replacing KD.
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29
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Larsen J, Stubbings V, Møller RS, Hjalgrim H. [Glucose transporter-1 deficiency syndrome can cause various clinical symptoms]. Ugeskr Laeger 2013; 175:V04130248. [PMID: 25353328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Glucose transporter-1 deficiency syndrome (GLUT1-DS) is caused by a decreased function of the glucose transporter GLUT1 protein, which is located in the blood brain barrier. This leads to inadequate glucose levels for brain metabolism and can cause various clinical symptoms including medically intractable epilepsy, developmental delay and complex movement disorders. Ketonic diet is the golden standard for treatment of GLUT1-DS. GLUT1-DS should be suspected in patients with early-onset intractable epilepsy with developmental delay or activity-induced movement disorders with or without epilepsy.
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Affiliation(s)
- Jan Larsen
- Forskning og Udvikling, Epilepsihospitalet. Artillerivej 100b, 5. tv., 2300 København S.
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30
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Abstract
The SLC37 family consists of four sugar-phosphate exchangers, A1, A2, A3, and A4, which are anchored in the endoplasmic reticulum (ER) membrane. The best characterized family member is SLC37A4, better known as the glucose-6-phosphate (G6P) transporter (G6PT). SLC37A1, SLC37A2, and G6PT function as phosphate (Pi)-linked G6P antiporters catalyzing G6P:Pi and Pi:Pi exchanges. The activity of SLC37A3 is unknown. G6PT translocates G6P from the cytoplasm into the lumen of the ER where it couples with either glucose-6-phosphatase-α (G6Pase-α) or G6Pase-β to hydrolyze intraluminal G6P to glucose and Pi. The functional coupling of G6PT with G6Pase-α maintains interprandial glucose homeostasis and the functional coupling of G6PT with G6Pase-β maintains neutrophil energy homeostasis and functionality. A deficiency in G6PT causes glycogen storage disease type Ib, an autosomal recessive disorder characterized by impaired glucose homeostasis, neutropenia, and neutrophil dysfunction. Neither SLC37A1 nor SLC37A2 can functionally couple with G6Pase-α or G6Pase-β, and there are no known disease associations for them or SLC37A3. Since only G6PT matches the characteristics of the physiological ER G6P transporter involved in blood glucose homeostasis and neutrophil energy metabolism, the biological roles for the other SLC37 proteins remain to be determined.
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Affiliation(s)
- Janice Y Chou
- Section on Cellular Differentiation, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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31
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Liu YY, Bao XH, Wang S, Fu N, Liu XY, Song FY, Yang YL, Wu Y, Zhang YH, Wu JX, Jiang YW, Qin J, Wu XR. [Clinical and genetic characteristics of glucose transporter type 1 deficiency syndrome]. Zhonghua Er Ke Za Zhi 2013; 51:443-447. [PMID: 24120063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVE To analyze the clinical and SLC2A1 gene mutation characteristics of glucose transporter type 1 deficiency syndrome. METHOD The detailed clinical manifestations of six cases were recorded. The laboratory tests including EEG, MRI, blood chemistry, and lumbar puncture were performed. SLC2A1 gene mutations were analyzed by PCR, DNA sequencing and multiplex ligation-dependent probe amplification (MLPA). RESULT Patient 1, 2 and 3 had classical clinical symptoms including infantile onset seizures, development delay. Patient 4, 5 and 6 had non-classical clinical symptoms including paroxysmal behavior disturbance, weakness, ataxia, lethargy, especially after fasting or exercise, without severe seizures. The plasma glucose levels were normal. The CSF glucose levels decreased in all the six cases, ranged from 1.10 mmol/L to 2.45 mmol/L, the mean level was 1.68 mmol/L. The CSF glucose/plasma glucose ratios decreased, ranged from 0.16 to 0.51, the mean ratio was 0.34. Four patients had normal EEG. Two patients had focal and diffuse epileptiform discharge, and one of them also had paroxysmal occipital or generalized high-amplitude slow waves during awake and sleep time. MRI abnormalities were found in three patients, patient 1 with mild brain atrophy, patient 3 with bilateral ventricle plump, and patient 4 with high signals in T2 in the frontal and occipital white matter, interpreted as hypomyelination. SLC2A1 gene mutations were found in six cases. Patient 1 has large scale deletion in exon 2. In patient 2 to 6, the mutations were c.741 G>A (E247K), 599delA, 761delA, c.1148 C>A (P383H), c.1198 C>T (R400C) respectively. Two patients were treated with ketogenic diet. The seizures disappeared and development became normal. Three patients responded to frequent meals with snacks. One patient refused any treatments, the symptoms continued to exist. CONCLUSION The clinical manifestations of glucose transporter type 1 deficiency syndrome are varied. The common symptoms included infantile onset seizures and various paroxysmal events. These neurologic symptoms generally fluctuated and were influenced by factors such as fasting or fatigue. This feature could be a very important clue for the diagnosis of GLUT1-DS. Lumbar puncture is recommended in patients with episodic CNS symptoms especially after fasting. GLUT1-DS is a treatable neurometabolic disorder, early diagnosis and treatment may improve the prognosis of the patients.
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Affiliation(s)
- Yan-yan Liu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
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32
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Abstract
Escherichia coli possesses a number of proteins that transport sugars out of the cell. We identified 31 candidate sugar efflux transporters based on their similarity to known sugar efflux transporters. We then tested whether these transporters affect arabinose and xylose metabolism. We identified 13 transporters – setC, cmr, ynfM, mdtD, yfcJ, yhhS, emrD, ydhC, ydeA, ybdA, ydeE, mhpT, and kgtP – that appeared to increase or decrease intracellular arabinose concentrations when respectively deleted or over-expressed. None of the candidate transporters affected xylose concentrations. These results indicate that E. coli possesses multiple arabinose efflux transporters. They also provide a novel target for future metabolic engineering.
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Affiliation(s)
- Khushnuma Koita
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Christopher V. Rao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- * E-mail:
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33
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Visser G, de Jager W, Verhagen LP, Smit GPA, Wijburg FA, Prakken BJ, Coffer PJ, Buitenhuis M. Survival, but not maturation, is affected in neutrophil progenitors from GSD-1b patients. J Inherit Metab Dis 2012; 35:287-300. [PMID: 21863279 DOI: 10.1007/s10545-011-9379-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 07/04/2011] [Accepted: 07/22/2011] [Indexed: 12/14/2022]
Abstract
Glycogen storage disease type 1b (GSD 1b) is caused by mutations in the Glucose-6-phosphate transporter and is characterized by impaired glucose homeostasis. In addition, GSD-1b is associated with chronic neutropenia resulting in recurrent infections and inflammatory bowel disease. It is unclear whether the neutropenia is solely due to enhanced apoptosis of mature neutrophils or whether aberrant neutrophil development may also contribute. Here we demonstrate that hematopoietic progenitors from GSD-1b patients are not impaired in their capacity to develop into mature neutrophils. However, optimal survival of neutrophil progenitors from GSD-1b patients requires high glucose levels (> 200 mg dl(-1)), suggesting that even under normoglycemic conditions these cells are more prone to apoptosis. Furthermore, analysis of cytokine levels in peripheral blood suggests an inflammatory state with an inverse correlation between the level of inflammation and the number of neutrophils. Finally, in some patients, with low numbers of peripheral blood neutrophils, high numbers of neutrophils were observed in the intestine. Together, these results suggest that the neutropenia observed in GSD-1b patients is not caused by impaired maturation, but may be caused by both increased levels of apoptosis and egress of neutrophils from the blood to the inflamed tissues.
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Affiliation(s)
- Gepke Visser
- Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
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Fung ELW, Ho YY, Hui J, Wong JH, Ng TB, Fong NYF, Klepper J, Tsui KWS. First report of GLUT1 deficiency syndrome in Chinese patients with novel and hot spot mutations in SLC2A1 gene. Brain Dev 2011; 33:170-3. [PMID: 20417043 DOI: 10.1016/j.braindev.2010.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 03/06/2010] [Accepted: 03/23/2010] [Indexed: 11/18/2022]
Abstract
Glucose transporter type 1 deficiency syndrome (GLUT1DS) is increasingly recognized as a cause of various neurological disorders but a high index of suspicion is important to make the diagnosis. We report two Chinese patients with GLUT1DS, one of which had a novel mutation in the SLC2A1 gene.
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Affiliation(s)
- Eva Lai-wah Fung
- Department of Paediatrics, The Chinese University of Hong Kong, China.
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35
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McCurdy DW, Dibley S, Cahyanegara R, Martin A, Patrick JW. Functional characterization and RNAi-mediated suppression reveals roles for hexose transporters in sugar accumulation by tomato fruit. Mol Plant 2010; 3:1049-63. [PMID: 20833733 DOI: 10.1093/mp/ssq050] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Hexoses accumulate to high concentrations (∼ 200 mM) in storage parenchyma cells of tomato fruit. Hexoses are sourced from the fruit apoplasm as hydrolysis products of phloem-imported sucrose. Three hexose transporters (LeHT1, LeHT2, LeHT3), expressed in fruit storage parenchyma cells, may contribute to hexose uptake by these cells. An analysis of their full-length sequences demonstrated that all three transporters belong to the STP sub-family of monosaccharide transporters that localize to plasma membranes. Heterologous expression of LeHT1 (and previously LeHT2, Gear et al., 2000), but not LeHT3, rescued a hexose transport-impaired yeast mutant when raised on glucose or fructose as the sole carbon source. Biochemically, LeHT1, similarly to LeHT2, exhibited transport properties consistent with a high-affinity glucose/H(+) symporter. Significantly, LeHT1 and LeHT2 also functioned as low-affinity fructose/H(+) symporters with apparent K(m) values commensurate with those of fruit tissues. A substantial reduction (80-90%) in fruit expression levels of all LeHT genes by RNAi-mediated knockdown caused a 55% decrease in fruit hexose accumulation. In contrast, photoassimilate production by source leaves and phloem transport capacity to fruit were unaffected by transporter knockdown. Collectively, these findings demonstrate that LeHTs play key roles in driving accumulation of hexoses into storage parenchyma cells during tomato fruit development.
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Affiliation(s)
- David W McCurdy
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
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36
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Feng X, Feistel T, Buffalo C, McCormack A, Kruvand E, Rodriguez-Contreras D, Akopyants NS, Umasankar PK, David L, Jardim A, Beverley SM, Landfear SM. Remodeling of protein and mRNA expression in Leishmania mexicana induced by deletion of glucose transporter genes. Mol Biochem Parasitol 2010; 175:39-48. [PMID: 20869991 DOI: 10.1016/j.molbiopara.2010.08.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 08/26/2010] [Accepted: 08/27/2010] [Indexed: 11/19/2022]
Abstract
Glucose is a major nutrient in the insect vector stage of Leishmania parasites. Glucose transporter null mutants of Leishmania mexicana exhibit profound phenotypic changes in both insect stage promastigotes and mammalian host stage amastigotes that reside within phagolysosomes of host macrophages. Some of these phenotypic changes could be either mediated or attenuated by changes in gene expression that accompany deletion of the glucose transporter genes. To search for changes in protein expression, the profile of proteins detected on two-dimensional gels was compared for wild type and glucose transporter null mutant promastigotes. A total of 50 spots whose intensities changed significantly and consistently in multiple experiments were detected, suggesting that a cohort of proteins is altered in expression levels in the null mutant parasites. Following identification of proteins by mass spectrometry, 3 such regulated proteins were chosen for more detailed analysis: mitochondrial aldehyde dehydrogenase, ribokinase, and hexokinase. Immunoblots employing antisera against these enzymes confirmed that their levels were upregulated, both in glucose transporter null mutants and in wild type parasites starved for glucose. Quantitative reverse transcriptase PCR (qRT-PCR) revealed that the levels of mRNAs encoding these enzymes were also enhanced. Global expression profiling using microarrays revealed a limited number of additional changes, although the sensitivity of the microarrays to detect modest changes in amplitude was less than that of two-dimensional gels. Hence, there is likely to be a network of proteins whose expression levels are altered by genetic ablation of glucose transporters, and much of this regulation may be reflected by changes in the levels of the cognate mRNAs. Some of these changes in protein expression may reflect an adaptive response of the parasites to limitation of glucose.
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Affiliation(s)
- Xiuhong Feng
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239, USA
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37
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Capul AA, Hickerson S, Barron T, Turco SJ, Beverley SM. Comparisons of mutants lacking the Golgi UDP-galactose or GDP-mannose transporters establish that phosphoglycans are important for promastigote but not amastigote virulence in Leishmania major. Infect Immun 2007; 75:4629-37. [PMID: 17606605 PMCID: PMC1951182 DOI: 10.1128/iai.00735-07] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Abundant surface Leishmania phosphoglycans (PGs) containing [Gal(beta1,4)Man(alpha1-PO(4))]-derived repeating units are important at several points in the infectious cycle of this protozoan parasite. PG synthesis requires transport of activated nucleotide-sugar precursors from the cytoplasm to the Golgi apparatus. Correspondingly, null mutants of the L. major GDP-mannose transporter LPG2 lack PGs and are severely compromised in macrophage survival and induction of acute pathology in susceptible mice, yet they are able to persist indefinitely and induce protective immunity. However, lpg2(-) L. mexicana amastigotes similarly lacking PGs but otherwise normal in known glycoconjugates remain able to induce acute pathology. To explore this further, we tested the infectivity of a new PG-null L. major mutant, which is inactivated in the two UDP-galactose transporter genes LPG5A and LPG5B. Surprisingly this mutant did not recapitulate the phenotype of L. major lpg2(-), instead resembling the L. major lipophosphoglycan-deficient lpg1(-) mutant. Metacyclic lpg5A(-)/lpg5B(-) promastigotes showed strong defects in the initial steps of macrophage infection and survival. However, after a modest delay, the lpg5A(-)/lpg5B(-) mutant induced lesion pathology in infected mice, which thereafter progressed normally. Amastigotes recovered from these lesions were fully infective in mice and in macrophages despite the continued absence of PGs. This suggests that another LPG2-dependent metabolite is responsible for the L. major amastigote virulence defect, although further studies ruled out cytoplasmic mannans. These data thus resolve the distinct phenotypes seen among lpg2(-) Leishmania species by emphasizing the role of glycoconjugates other than PGs in amastigote virulence, while providing further support for the role of PGs in metacyclic promastigote virulence.
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Affiliation(s)
- Althea A Capul
- Department of Molecular Microbiology, Washington University School of Medicine, Campus Box 8230, 660 S. Euclid Avenue, St. Louis, MO 63110, USA
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Sparrow LG, Gorman JJ, Strike PM, Robinson CP, McKern NM, Epa VC, Ward CW. The location and characterisation of the O-linked glycans of the human insulin receptor. Proteins 2006; 66:261-5. [PMID: 17078079 DOI: 10.1002/prot.21261] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
O-linked glycosylation is a post-translational and post-folding event involving exposed S/T residues at beta-turns or in regions with extended conformation. O-linked sites are difficult to predict from sequence analyses compared to N-linked sites. Here we compare the results of chemical analyses of isolated glycopeptides with the prediction using the neural network prediction method NetOGlyc3.1, a procedure that has been reported to correctly predict 76% of O-glycosylated residues in proteins. Using the heavily glycosylated human insulin receptor as the test protein six sites of mucin-type O-glycosylation were found at residues T744, T749, S757, S758, T759, and T763 compared to the three sites (T759 and T763- correctly, T756- incorrectly) predicted by the neural network method. These six sites occur in a 20 residue segment that begins nine residues downstream from the start of the insulin receptor beta-chain. This region which also includes N-linked glycosylation sites at N742 and N755, is predicted to lack secondary structure and is followed by residues 765-770, the known linear epitope for the monoclonal antibody 18-44.
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Affiliation(s)
- Lindsay G Sparrow
- Commonwealth Scientific and Industrial Research Organisation, Molecular and Health Technologies, Parkville, Victoria 3052, Australia
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39
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Abstract
Leukocyte adhesion deficiency II (LAD II) belongs to a group of human congenital diseases in which the interactions of leukocytes with the vascular endothelium are strongly impaired. LAD II is based on a defect in the synthesis of fucosylated glycostructures. This leads to an immunodeficiency owing to the absence of functional selectin ligands and to strong psychomotor defects, as a result of as-yet unknown reasons. In this review we focused on the current controversies, and open questions that have arisen from recent studies on the genetic defect, therapy and the basis of psychomotor defects in LAD II.
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Affiliation(s)
- Sviatlana Yakubenia
- Max Planck Institute for Molecular Biomedicine and Institute of Cell Biology, ZMBE, University of Münster, Münster, Germany
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40
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Belkaid A, Copland IB, Massillon D, Annabi B. Silencing of the human microsomal glucose-6-phosphate translocase induces glioma cell death: Potential new anticancer target for curcumin. FEBS Lett 2006; 580:3746-52. [PMID: 16777101 DOI: 10.1016/j.febslet.2006.05.071] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 05/19/2006] [Accepted: 05/31/2006] [Indexed: 01/15/2023]
Abstract
G6P translocase (G6PT) is thought to play a crucial role in transducing intracellular signaling events in brain tumor-derived cancer cells. In this report, we investigated the contribution of G6PT to the control of U-87 brain tumor-derived glioma cell survival using small interfering RNA (siRNA)-mediated suppression of G6PT. Three siRNA constructs were generated and found to suppress up to 91% G6PT gene expression. Flow cytometry analysis of propidium iodide/annexin-V-stained cells indicated that silencing the G6PT gene induced necrosis and late apoptosis. The anticancer agent curcumin, also inhibited G6PT gene expression by more than 90% and triggered U-87 glioma cells death. Overexpression of recombinant G6PT rescued the cells from curcumin-induced cell death. Targeting G6PT expression may provide a new mechanistic rationale for the action of chemopreventive drugs and lead to the development of new anti-cancer strategies.
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Affiliation(s)
- Anissa Belkaid
- Laboratoire d'Oncologie Moléculaire, Département de Chimie, Centre BIOMED, Université du Québec à Montréal, C.P. 8888, Succ. Centre-ville, Montréal, Que., Canada H3C 3P8
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41
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Carvalho E, Kotani K, Peroni OD, Kahn BB. Adipose-specific overexpression of GLUT4 reverses insulin resistance and diabetes in mice lacking GLUT4 selectively in muscle. Am J Physiol Endocrinol Metab 2005; 289:E551-61. [PMID: 15928024 DOI: 10.1152/ajpendo.00116.2005] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Adipose tissue plays an important role in glucose homeostasis and affects insulin sensitivity in other tissues. In obesity and type 2 diabetes, glucose transporter 4 (GLUT4) is downregulated in adipose tissue, and glucose transport is also impaired in muscle. To determine whether overexpression of GLUT4 selectively in adipose tissue could prevent insulin resistance when glucose transport is impaired in muscle, we bred muscle GLUT4 knockout (MG4KO) mice to mice overexpressing GLUT4 in adipose tissue (AG4Tg). Overexpression of GLUT4 in fat not only normalized the fasting hyperglycemia and glucose intolerance in MG4KO mice, but it reduced these parameters to below normal levels. Glucose infusion rate during a euglycemic clamp study was reduced 46% in MG4KO compared with controls and was restored to control levels in AG4Tg-MG4KO. Similarly, insulin action to suppress hepatic glucose production was impaired in MG4KO mice and was restored to control levels in AG4Tg-MG4KO. 2-deoxyglucose uptake during the clamp was increased approximately twofold in white adipose tissue but remained reduced in skeletal muscle of AG4Tg-MG4KO mice. AG4Tg and AG4Tg-MG4KO mice have a slight increase in fat mass, a twofold elevation in serum free fatty acids, an approximately 50% increase in serum leptin, and a 50% decrease in serum adiponectin. In MG4KO mice, serum resistin is increased 34% and GLUT4 overexpression in fat reverses this. Overexpression of GLUT4 in fat also reverses the enhanced clearance of an oral lipid load in MG4KO mice. Thus overexpression of GLUT4 in fat reverses whole body insulin resistance in MG4KO mice without restoring glucose transport in muscle. This effect occurs even though AG4Tg-MG4KO mice have increased fat mass and low adiponectin and is associated with normalization of elevated resistin levels.
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Affiliation(s)
- Eugenia Carvalho
- Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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43
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Yang Q, Graham TE, Mody N, Preitner F, Peroni OD, Zabolotny JM, Kotani K, Quadro L, Kahn BB. Serum retinol binding protein 4 contributes to insulin resistance in obesity and type 2 diabetes. Nature 2005; 436:356-62. [PMID: 16034410 DOI: 10.1038/nature03711] [Citation(s) in RCA: 1470] [Impact Index Per Article: 77.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 05/03/2005] [Indexed: 01/08/2023]
Abstract
In obesity and type 2 diabetes, expression of the GLUT4 glucose transporter is decreased selectively in adipocytes. Adipose-specific Glut4 (also known as Slc2a4) knockout (adipose-Glut4(-/-)) mice show insulin resistance secondarily in muscle and liver. Here we show, using DNA arrays, that expression of retinol binding protein-4 (RBP4) is elevated in adipose tissue of adipose-Glut4(-/-) mice. We show that serum RBP4 levels are elevated in insulin-resistant mice and humans with obesity and type 2 diabetes. RBP4 levels are normalized by rosiglitazone, an insulin-sensitizing drug. Transgenic overexpression of human RBP4 or injection of recombinant RBP4 in normal mice causes insulin resistance. Conversely, genetic deletion of Rbp4 enhances insulin sensitivity. Fenretinide, a synthetic retinoid that increases urinary excretion of RBP4, normalizes serum RBP4 levels and improves insulin resistance and glucose intolerance in mice with obesity induced by a high-fat diet. Increasing serum RBP4 induces hepatic expression of the gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK) and impairs insulin signalling in muscle. Thus, RBP4 is an adipocyte-derived 'signal' that may contribute to the pathogenesis of type 2 diabetes. Lowering RBP4 could be a new strategy for treating type 2 diabetes.
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Affiliation(s)
- Qin Yang
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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44
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Ito Y, Gertsen E, Oguni H, Nakayama T, Matsuo M, Funatsuka M, Voit T, Klepper J, Osawa M. Clinical presentation, EEG studies, and novel mutations in two cases of GLUT1 deficiency syndrome in Japan. Brain Dev 2005; 27:311-7. [PMID: 15862198 DOI: 10.1016/j.braindev.2004.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Revised: 08/19/2004] [Accepted: 09/12/2004] [Indexed: 11/15/2022]
Abstract
We report the first two Japanese children diagnosed with glucose transporter type 1 (GLUT1) deficiency syndrome. Both boys had been treated under the initial diagnosis of epilepsy and were reinvestigated for previously unexplainable hypoglycorrhachia. Myoclonic seizures developed at 4 months of age in Patient #1 (7 years old), and at 2 months of age in Patient #2 (11 years old), followed by cerebellar ataxia, spastic diplegia, and mental retardation. Both patients had hypoglycorrhachia, and the symptoms were more severe in the latter. CSF and serum glucose levels determined simultaneously showed a CSF/serum glucose ratio of below 0.4 in both patients. In mildly affected Patient #1, the postprandial waking EEG showed improvement in the background activity, as compared to that recorded after overnight fasting, while no significant changes were observed in severely affected Patient #2. In both patients, the functional GLUT1 defect was confirmed by 3-O-methyl-D-glucose uptake into erythrocytes. Molecular analyses identified heterozygous novel mutations in both patients, within exons 6 and 2 of the GLUT1 gene, respectively. The ketogenic diet was refused in Patient #1, but started in Patient #2 with significant clinical benefit. Fasting CSF analysis and pre-/postprandial EEG changes in children with epileptic seizures and unexplainable neurological deterioration help in diagnosing this potentially treatable disorder.
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Affiliation(s)
- Yasushi Ito
- Department of Pediatrics, School of Medicine, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
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Abstract
Impaired glucose transport across the blood-brain barrier results in Glut-1 deficiency syndrome (Glut-1 DS, OMIM 606777), characterized by infantile seizures, developmental delay, acquired microcephaly, spasticity, ataxia, and hypoglycorrhachia. We studied 16 new Glut-1 deficiency syndrome patients focusing on clinical and laboratory features, molecular genetics, genotype-phenotype correlation, and treatment. These patients were classified phenotypically into three groups. The mean cerebrospinal fluid glucose concentration was 33.1 +/- 4.9mg/dl equal to 37% of the simultaneous blood glucose concentration. The mean cerebrospinal fluid lactate concentration was 1.0 +/- 0.3mM, which was less than the normal mean value of 1.63mM. The mean V(max) for the 3-O-methyl-D-glucose uptake into erythrocytes was 996 fmol/10(6) red blood cells per second, significantly less (54 +/- 11%; t test, p < 0.05) than the mean control value of 1,847. The mean Km value for the patient group (1.4 +/- 0.5mM) was similar to the control group (1.7 +/- 0.5mM; t test, p > 0.05). We identified 16 rearrangements, including seven missense, one nonsense, one insertion, and seven deletion mutations. Fourteen were novel mutations. There were no obvious correlations between phenotype, genotype, or biochemical measures. The ketogenic diet produced good seizure control.
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Affiliation(s)
- Dong Wang
- Colleen Giblin Laboratories for Pediatric Neurology Research, Department of Neurology, Columbia University, 710 West 168th Street, New York, NY 10032, USA
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46
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Wong HY, Chu TS, Chan YW, Fok TF, Fung LW, Fung KP, Ho YY. The effects of phenytoin and its metabolite 5-(4-hydroxyphenyl)-5-phenylhydantoin on cellular glucose transport. Life Sci 2005; 76:1859-72. [PMID: 15698863 DOI: 10.1016/j.lfs.2004.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Accepted: 10/20/2004] [Indexed: 11/16/2022]
Abstract
Glucose is the principal fuel for brain metabolism and its movement across the blood-brain barrier depends on Glut1. Impaired glucose transport to the brain may have deleterious consequences. For example, Glut1 deficiency syndrome (Glut1DS) is the result of heterozygous loss of function Glut1 mutation leading to energy failure of the brain and subsequently, epileptic encephalopathy. To preserve the integrity of the energy supply to the brain in patients with compromised glucose transport function, consumption of compounds with glucose transport inhibiting properties should be avoided. Phenytoin is a widely used anticonvulsant that affects carbohydrate metabolism. In this study, the hypothesis that phenytoin and its metabolite 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) affect cellular glucose transport was tested. With a focus on Glut1, the effects of phenytoin and HPPH on cellular glucose transport were studied. Glucose uptake assay measuring the zero-trans influx of radioactive-labeled glucose analogues showed that phenytoin and HPPH did not exert immediate effects on erythrocyte Glut1 activity or glucose transport in Hs68 control fibroblasts, Glut1DS primary fibroblasts isolated from two patients, or in rat primary astrocytes. Prolonged exposure to the two compounds could stimulate glucose transport by up to 30-60% over the control level (p <0.05) in Hs68 and Glut1DS fibroblasts as well as in rat astrocytes. The stimulation of glucose transport by HPPH was dose-dependent and accompanied by an up-regulation of GLUT1 mRNA expression (p <0.05). In conclusion, phenytoin and HPPH do not compromise cellular glucose transport. Prolonged exposure to these compounds can modify carbohydrate homeostasis by up-regulating glucose transport in both normal and Glut1DS conditions in vitro.
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Affiliation(s)
- Hei Yi Wong
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
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47
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Peinado RA, Moreno JJ, Medina M, Mauricio JC. Potential application of a glucose-transport-deficient mutant of Schizosaccharomyces pombe for removing gluconic acid from grape must. J Agric Food Chem 2005; 53:1017-1021. [PMID: 15713014 DOI: 10.1021/jf048764b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Musts from rotten grapes typically contain high levels of gluconic acid, which can raise severe problems in winemaking processes. In this work, the ability of the glucose-transport-deficient mutant YGS-5 of Schizosaccharomyces pombe to completely or partly remove gluconic acid from a synthetic glucose-containing medium and the potential use of this yeast strain for the same purpose in musts and wines were examined. Surprisingly, the S. pombe YGS-5 strain successfully removed 93% of the initial gluconic acid (2.5 gL(-1)) and 80% of the initial malic acid (1.0 gL(-1)) within 30 h after inoculation. Also, the yeast strain produced no volatile compounds other than those obtained in fermentations conducted with the wine yeast Saccharomyces cerevisiae. S. pombe YGS-5 could thus be used to remove gluconic acid present in musts from rotten grapes. On the basis of these results, various ways of using S. pombe YGS-5 to treat musts containing gluconic acid in order to solve the problems due to the high gluconic acid concentrations in botrytized grape must are proposed.
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Affiliation(s)
- Rafael A Peinado
- Departamento de Química Agrícola y Edafología, Edificio C-3, Universidad de Córdoba, Campus Universitario Rabanales, 14014 Córdoba, Spain
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48
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Park JL, Heilig CW, Brosius FC. GLUT1-deficient mice exhibit impaired endothelium-dependent vascular relaxation. Eur J Pharmacol 2005; 496:213-4. [PMID: 15288593 DOI: 10.1016/j.ejphar.2004.06.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Revised: 05/25/2004] [Accepted: 06/02/2004] [Indexed: 11/22/2022]
Abstract
We tested the hypothesis that decreased glucose transporter 1 (GLUT1) expression alters endothelial function. Nitric oxide-dependent endothelial relaxation, but not endothelium-independent relaxation, was significantly reduced in aortas from transgenic mice expressing GLUT1 antisense mRNA, compared to aortas from nontransgenic littermates. These data suggest that GLUT1-dependent glucose metabolism may play an important role in regulating endothelial function.
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Affiliation(s)
- James L Park
- Internal Medicine, Division of Nephrology, University of Michigan Medical School, 1560 MSRB 2, 1150 W. Medical Center Drive, Ann Arbor, MI 48109-0676, USA
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Kaymaz AA, Tamer S, Albeniz I, Cefle K, Palanduz S, Ozturk S, Salmayenli N. Alterations in rheological properties and erythrocyte membrane proteins in cats with diabetes mellitus. Clin Hemorheol Microcirc 2005; 33:81-8. [PMID: 16151255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Many studies have shown that diabetes mellitus is associated with increased whole and blood viscosity and decreased erythrocyte deformability. It has been suggested that these abnormalities in blood rheology may play a causative role in the pathogenesis of diabetic vascular complications. However, less is known about the content and quality of membrane proteins which may contribute to abnormalities in membrane dynamic and decreased erythrocyte deformability. In the present study we analysed various rheological parameters (blood and plasma viscosity, erythrocyte deformability, haemotological parameters), in cats with non-insulin dependent diabetes mellitus (NIDDM). We also investigated alterations in erythrocyte membrane protein content by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). We found that erythrocyte rigidity and plasma and whole blood viscosities were significantly higher in cats with NIDDM compared to controls. SDS-PAGE revealed that the band 5 corresponding to actin was weaker while band 4.5 corresponding to integral membrane proteins (glycophorin A, B and C) had disappeared. Also, band 4.9, which is composed of dematin (a protein with actin-bundling capacity) was lost. We suggest that the observed abnormalities in membrane proteins may play a role in reduced erythrocyte deformability associated with diabetes mellitus.
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Affiliation(s)
- Alev Akdogan Kaymaz
- Istanbul University, Istanbul Veterinary Faculty, Department of Internal Diseaes, Istanbul, Turkey
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50
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Hammarstedt A, Sopasakis VR, Gogg S, Jansson PA, Smith U. Improved insulin sensitivity and adipose tissue dysregulation after short-term treatment with pioglitazone in non-diabetic, insulin-resistant subjects. Diabetologia 2005; 48:96-104. [PMID: 15624096 DOI: 10.1007/s00125-004-1612-3] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Accepted: 09/14/2004] [Indexed: 10/26/2022]
Abstract
AIMS/HYPOTHESIS We examined whether short-term treatment with a thiazolidinedione improves insulin sensitivity in non-obese but insulin-resistant subjects and whether this is associated with an improvement in dysregulated adipose tissue (reduced expression of IRS-1, GLUT4, PPARgamma co-activator 1 and markers of terminal differentiation) that we have previously documented to be associated with insulin resistance. METHODS Ten non-diabetic subjects, identified as having low IRS-1 and GLUT-4 protein in adipose cells as markers of insulin resistance, underwent 3 weeks of treatment with pioglitazone. The euglycaemic-hyperinsulinaemic clamp technique was used to measure insulin sensitivity before and after treatment. Serum samples were analysed for glucose, insulin, lipids, total and high-molecular-weight (HMW) adiponectin levels. Biopsies from abdominal subcutaneous adipose tissue were taken, cell size measured, mRNA and protein extracted and quantified using real-time RT-PCR and Western blot. RESULTS Insulin sensitivity was improved after 3 weeks treatment and circulating total as well as HMW adiponectin increased in all subjects, while no effect was seen on serum lipids. In the adipose cells, gene and protein expression of IRS-1 and PPARgamma co-activator 1 remained unchanged, while adiponectin, adipocyte P 2, uncoupling protein 2, GLUT4 and liver X receptor-alpha increased. Insulin-stimulated tyrosine phosphorylation and p-ser-PKB/Akt increased, while no significant effect of thiazolidinedione treatment was seen on the inflammatory status of the adipose tissue in these non-obese subjects. CONCLUSIONS/INTERPRETATION Short-term treatment with pioglitazone improved insulin sensitivity in the absence of any changes in circulating NEFA or lipid levels. Several markers of adipose cell differentiation, previously shown to be reduced in insulin resistance, were augmented, supporting the concept that insulin resistance in these individuals is associated with impaired terminal differentiation of the adipose cells.
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Affiliation(s)
- A Hammarstedt
- The Lundberg Laboratory for Diabetes Research, Department of Internal Medicine, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden
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