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Yin L, Niu Y, Zheng X, Chu J, Ma T. d-galactose causes embryonic development arrest and placental development disorders in mice by increasing ROS and inhibiting SIRT1/FOXO3a axis. Placenta 2024; 150:52-61. [PMID: 38593636 DOI: 10.1016/j.placenta.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 03/17/2024] [Accepted: 04/05/2024] [Indexed: 04/11/2024]
Abstract
INTRODUCTION Does an elevation in d-Galactose (D-Gal) levels within the body contribute to abnormal embryonic development and placental dysfunction during pregnancy? METHODS Mouse embryos were cultivated to the blastocyst stage under varying concentrations of D-Gal. The blastocyst formation rate was measured, and the levels of reactive oxygen species (ROS), sirtuin 1 (SIRT1), and forkhead box O3a (FOXO3a) in blastocysts were assessed. Mice were intraperitoneally injected with either saline or D-Gal with or without SRT1720. On the 14th day of pregnancy, the fetal absorption rate and placental weight were recorded. Placental levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. The expression of senescence-related factors, such as senescence-associated β-galactosidase (SA-β-gal) in the placenta was examined, and the expression of placental SIRT1, FOXO3a and p21 was evaluated by immunohistochemistry and Western blotting. RESULTS D-Gal adversely affects early embryonic development in vitro, resulting in a decreased blastocyst formation rate. Furthermore, D-Gal downregulates SIRT1 and FOXO3a while increasing ROS levels in blastocysts. Concurrently, D-Gal induces placental dysfunction, characterized by an elevated fetal absorption rate, reduced placental weight, diminished SOD activity, and increased MDA content. The senescence-related factor SA-β-gal was detected in the placenta, along with altered expression of placental SIRT1, FOXO3a, and p21. The SIRT1 agonist SRT1720 mitigated this damage by increasing SIRT1 and FOXO3a expression. DISCUSSION The inhibition of early embryonic development and placental dysfunction induced by D-Gal may be attributed to the dysregulation of SIRT1. Activating SIRT1 emerges as a potentially effective strategy for alleviating the adverse effects of D-Gal exposure.
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Affiliation(s)
- Lanlan Yin
- Reproductive Medicine Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Yanru Niu
- Laboratory of Bone Science, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Xiudan Zheng
- Reproductive Medicine Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Jiaqi Chu
- Stem Cell Research and Cellular Therapy Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China.
| | - Tianzhong Ma
- Reproductive Medicine Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China.
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Balakrishnan B, Yan X, McCue MD, Bellagamba O, Guo A, Winkler F, Thall J, Crawford L, Dimen R, Chen S, McEnaney S, Wu Y, Zimmer M, Sarkis J, Martini PG, Finn PF, Lai K. Whole-body galactose oxidation as a robust functional assay to assess the efficacy of gene-based therapies in a mouse model of Galactosemia. Mol Ther Methods Clin Dev 2024; 32:101191. [PMID: 38352271 PMCID: PMC10863324 DOI: 10.1016/j.omtm.2024.101191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 01/12/2024] [Indexed: 02/16/2024]
Abstract
Despite the implementation of lifesaving newborn screening programs and a galactose-restricted diet, many patients with classic galactosemia develop long-term debilitating neurological deficits and primary ovarian insufficiency. Previously, we showed that the administration of human GALT mRNA predominantly expressed in the GalT gene-trapped mouse liver augmented the expression of hepatic GALT activity, which decreased not only galactose-1 phosphate (gal-1P) in the liver but also peripheral tissues. Since each peripheral tissue requires distinct methods to examine the biomarker and/or GALT effect, this highlights the necessity for alternative strategies to evaluate the overall impact of therapies. In this study, we established that whole-body galactose oxidation (WBGO) as a robust, noninvasive, and specific method to assess the in vivo pharmacokinetic and pharmacodynamic parameters of two experimental gene-based therapies that aimed to restore GALT activity in a mouse model of galactosemia. Although our results illustrated the long-lasting efficacy of AAVrh10-mediated GALT gene transfer, we found that GALT mRNA therapy that targets the liver predominantly is sufficient to sustain WBGO. The latter could have important implications in the design of novel targeted therapy to ensure optimal efficacy and safety.
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Affiliation(s)
- Bijina Balakrishnan
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | | | | | - Olivia Bellagamba
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | - Aaron Guo
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | | | | | | | | | | | | | - Yiman Wu
- Moderna, Cambridge, MA 02139, USA
| | | | | | | | | | - Kent Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
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3
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Panis B, Vos EN, Barić I, Bosch AM, Brouwers MCGJ, Burlina A, Cassiman D, Coman DJ, Couce ML, Das AM, Demirbas D, Empain A, Gautschi M, Grafakou O, Grunewald S, Kingma SDK, Knerr I, Leão-Teles E, Möslinger D, Murphy E, Õunap K, Pané A, Paci S, Parini R, Rivera IA, Scholl-Bürgi S, Schwartz IVD, Sdogou T, Shakerdi LA, Skouma A, Stepien KM, Treacy EP, Waisbren S, Berry GT, Rubio-Gozalbo ME. Brain function in classic galactosemia, a galactosemia network (GalNet) members review. Front Genet 2024; 15:1355962. [PMID: 38425716 PMCID: PMC10902464 DOI: 10.3389/fgene.2024.1355962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 01/24/2024] [Indexed: 03/02/2024] Open
Abstract
Classic galactosemia (CG, OMIM #230400, ORPHA: 79,239) is a hereditary disorder of galactose metabolism that, despite treatment with galactose restriction, affects brain function in 85% of the patients. Problems with cognitive function, neuropsychological/social emotional difficulties, neurological symptoms, and abnormalities in neuroimaging and electrophysiological assessments are frequently reported in this group of patients, with an enormous individual variability. In this review, we describe the role of impaired galactose metabolism on brain dysfunction based on state of the art knowledge. Several proposed disease mechanisms are discussed, as well as the time of damage and potential treatment options. Furthermore, we combine data from longitudinal, cross-sectional and retrospective studies with the observations of specialist teams treating this disease to depict the brain disease course over time. Based on current data and insights, the majority of patients do not exhibit cognitive decline. A subset of patients, often with early onset cerebral and cerebellar volume loss, can nevertheless experience neurological worsening. While a large number of patients with CG suffer from anxiety and depression, the increased complaints about memory loss, anxiety and depression at an older age are likely multifactorial in origin.
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Affiliation(s)
- Bianca Panis
- Department of Pediatrics, MosaKids Children’s Hospital, Maastricht University Medical Centre, Maastricht, Netherlands
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- United for Metabolic Diseases (UMD), Amsterdam, Netherlands
| | - E. Naomi Vos
- Department of Pediatrics, MosaKids Children’s Hospital, Maastricht University Medical Centre, Maastricht, Netherlands
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- United for Metabolic Diseases (UMD), Amsterdam, Netherlands
- Department of Clinical Genetics, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW School for Oncology and Reproduction, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Ivo Barić
- Department of Pediatrics, University Hospital Center Zagreb, Croatia, and School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Annet M. Bosch
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- United for Metabolic Diseases (UMD), Amsterdam, Netherlands
- Department of Pediatrics, Division of Metabolic Diseases, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Gastroenterology Endocrinology Metabolism, Inborn Errors of Metabolism, Amsterdam, Netherlands
| | - Martijn C. G. J. Brouwers
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Department of Internal Medicine, Division of Endocrinology and Metabolic Disease, Maastricht University Medical Centre, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Alberto Burlina
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Division of Inherited Metabolic Diseases, Reference Centre Expanded Newborn Screening, University Hospital Padova, Padova, Italy
| | - David Cassiman
- Laboratory of Hepatology, Department of Chronic Diseases, Metabolism and Ageing, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - David J. Coman
- Queensland Children’s Hospital, Children’s Health Queensland, Brisbane, QLD, Australia
| | - María L. Couce
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Department of Pediatrics, Diagnosis and Treatment Unit of Congenital Metabolic Diseases, University Clinical Hospital of Santiago de Compostela, IDIS-Health Research Institute of Santiago de Compostela, CIBERER, RICORS Instituto Salud Carlos III, Santiago de Compostela, Spain
| | - Anibh M. Das
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Department of Paediatrics, Pediatric Metabolic Medicine, Hannover Medical School, Hannover, Germany
| | - Didem Demirbas
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Manton Center for Orphan Disease Research, Boston, MA, United States
| | - Aurélie Empain
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Department of Paediatrics, Metabolic and Nutrition Unit, Division of Endocrinology, Diabetes and Metabolism, University Hospital for Children Queen Fabiola, Bruxelles, Belgium
| | - Matthias Gautschi
- Department of Paediatrics, Institute of Clinical Chemistry, Inselspital, Bern University Hospital, Swiss Reference Centre for Inborn Errors of Metabolism, Site Bern, Division of Pediatric Endocrinology, Diabetes and Metabolism, University of Bern, Bern, Switzerland
| | - Olga Grafakou
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- IEM Clinic, Arch Makarios III Hospital, Nicosia, Cyprus
| | - Stephanie Grunewald
- Metabolic Unit Great Ormond Street Hospital and Institute for Child Health, University College London, London, United Kingdom
| | - Sandra D. K. Kingma
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Centre for Metabolic Diseases, University Hospital Antwerp, University of Antwerp, Antwerp, Belgium
| | - Ina Knerr
- National Centre for Inherited Metabolic Disorders, Children’s Health Ireland at Temple Street, University College Dublin, Dublin, Ireland
| | - Elisa Leão-Teles
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universitário São João, Porto, Portugal
| | - Dorothea Möslinger
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Department of Paediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Elaine Murphy
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery (NHNN), London, United Kingdom
| | - Katrin Õunap
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Genetics and Personalized Medicine Clinic, Faculty of Medicine, Tartu University Hospital, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Adriana Pané
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Endocrinology and Nutrition Department, Hospital Clínic de Barcelona, Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Sabrina Paci
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Inborn Errors of Metabolism, Clinical Department of Pediatrics, San Paolo Hospital - ASST Santi Paolo e Carlo, University of Milan, Milan, Italy
| | - Rossella Parini
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Rare Diseases Unit, Department of Internal Medicine, San Gerardo Hospital IRCCS, Monza, Italy
| | - Isabel A. Rivera
- iMed.ULisboa–Instituto de Investigação do Medicamento, Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
| | - Sabine Scholl-Bürgi
- Department of Child and Adolescent Health, Division of Pediatrics I-Inherited Metabolic Disorders, Medical University Innsbruck, Innsbruck, Austria
| | - Ida V. D. Schwartz
- Medical Genetics Service, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil
| | - Triantafyllia Sdogou
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Newborn Screening Department, Institute of Child Health, Athens, Greece
| | - Loai A. Shakerdi
- Adult Metabolics/Genetics, National Centre for Inherited Metabolic Disorders, The Mater Misericordiae University Hospital, Dublin, Ireland
| | - Anastasia Skouma
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- Newborn Screening Department, Institute of Child Health, Athens, Greece
| | - Karolina M. Stepien
- Salford Royal Organisation, Northern Care Alliance NHS Foundation Trust, Salford, United Kingdom
| | - Eileen P. Treacy
- School of Medicine, Trinity College Dublin, National Rare Diseases Office, Mater Misericordiae University Hospital, Dublin, Ireland
| | - Susan Waisbren
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Manton Center for Orphan Disease Research, Boston, MA, United States
| | - Gerard T. Berry
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Manton Center for Orphan Disease Research, Boston, MA, United States
| | - M. Estela Rubio-Gozalbo
- Department of Pediatrics, MosaKids Children’s Hospital, Maastricht University Medical Centre, Maastricht, Netherlands
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member, Padova, Italy
- United for Metabolic Diseases (UMD), Amsterdam, Netherlands
- Department of Clinical Genetics, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW School for Oncology and Reproduction, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
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Teixeira LF, Prauchner GRK, Gusso D, Wyse ATS. Classical Hereditary galactosemia: findings in patients and animal models. Metab Brain Dis 2024; 39:239-248. [PMID: 37702899 DOI: 10.1007/s11011-023-01281-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/21/2023] [Indexed: 09/14/2023]
Abstract
Classic galactosemia is a rare inborn error of metabolism that affects the metabolism of galactose, a sugar derived from milk and derivates. Classic galactosemia is caused by variants of the GALT gene, which lead to absent or misfolded forms of the ubiquitously present galactose-1-phosphate uridylyltransferase enzyme (GALT) driving galactose metabolites to accumulate, damaging cells from neurons to hepatocytes. The disease has different prevalence around the world due to different allele frequencies among populations and its symptoms range from cognitive and psychomotor impairment to hepatic, ophthalmological, and bone structural damage. The practice of newborn screening still varies among countries, dairy restriction treatment is a consensus despite advances in preclinical treatment strategies. Recent clinical studies in Duarte variant suggest dairy restriction could be reconsidered in these cases. Despite noteworthy advances in the classic galactosemia understanding, preclinical trials are still crucial to fully understand the pathophysiology of the disease and help propose new treatments. This review aims to report a comprehensive analysis of past studies and state of art research on galactosemia screening, its clinical and preclinical trials, and treatments with the goal of shedding light on this complex and multisystemic innate error of the metabolism.
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Affiliation(s)
- Lucas Ferreira Teixeira
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry - Wyse's Lab - ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Gustavo R Krupp Prauchner
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry - Wyse's Lab - ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Darlan Gusso
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry - Wyse's Lab - ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Angela T S Wyse
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry - Wyse's Lab - ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
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Derks B, Rivera-Cruz G, Hagen-Lillevik S, Vos EN, Demirbas D, Lai K, Treacy EP, Levy HL, Wilkins-Haug LE, Rubio-Gozalbo ME, Berry GT. The hypergonadotropic hypogonadism conundrum of classic galactosemia. Hum Reprod Update 2023; 29:246-258. [PMID: 36512573 PMCID: PMC9976963 DOI: 10.1093/humupd/dmac041] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/19/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Hypergonadotropic hypogonadism is a burdensome complication of classic galactosemia (CG), an inborn error of galactose metabolism that invariably affects female patients. Since its recognition in 1979, data have become available regarding the clinical spectrum, and the impact on fertility. Many women have been counseled for infertility and the majority never try to conceive, yet spontaneous pregnancies can occur. Onset and mechanism of damage have not been elucidated, yet new insights at the molecular level are becoming available that might greatly benefit our understanding. Fertility preservation options have expanded, and treatments to mitigate this complication either by directly rescuing the metabolic defect or by influencing the cascade of events are being explored. OBJECTIVE AND RATIONALE The aims are to review: the clinical picture and the need to revisit the counseling paradigm; insights into the onset and mechanism of damage at the molecular level; and current treatments to mitigate ovarian damage. SEARCH METHODS In addition to the work on this topic by the authors, the PubMed database has been used to search for peer-reviewed articles and reviews using the following terms: 'classic galactosemia', 'gonadal damage', 'primary ovarian insufficiency', 'fertility', 'animal models' and 'fertility preservation' in combination with other keywords related to the subject area. All relevant publications until August 2022 have been critically evaluated and reviewed. OUTCOMES A diagnosis of premature ovarian insufficiency (POI) results in a significant psychological burden with a high incidence of depression and anxiety that urges adequate counseling at an early stage, appropriate treatment and timely discussion of fertility preservation options. The cause of POI in CG is unknown, but evidence exists of dysregulation in pathways crucial for folliculogenesis such as phosphatidylinositol 3-kinase/protein kinase B, inositol pathway, mitogen-activated protein kinase, insulin-like growth factor-1 and transforming growth factor-beta signaling. Recent findings from the GalT gene-trapped (GalTKO) mouse model suggest that early molecular changes in 1-month-old ovaries elicit an accelerated growth activation and burnout of primordial follicles, resembling the progressive ovarian failure seen in patients. Although data on safety and efficacy outcomes are still limited, ovarian tissue cryopreservation can be a fertility preservation option. Treatments to overcome the genetic defect, for example nucleic acid therapy such as mRNA or gene therapy, or that influence the cascade of events are being explored at the (pre-)clinical level. WIDER IMPLICATIONS Elucidation of the molecular pathways underlying POI of any origin can greatly advance our insight into the pathogenesis and open new treatment avenues. Alterations in these molecular pathways might serve as markers of disease progression and efficiency of new treatment options.
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Affiliation(s)
- Britt Derks
- Department of Pediatrics and Clinical Genetics, Maastricht University Medical Centre+, Maastricht, The Netherlands.,GROW, Maastricht University, Maastricht, The Netherlands.,European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member and United for Metabolic Diseases Member
| | - Greysha Rivera-Cruz
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Synneva Hagen-Lillevik
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah College of Health, Salt Lake City, UT, USA
| | - E Naomi Vos
- Department of Pediatrics and Clinical Genetics, Maastricht University Medical Centre+, Maastricht, The Netherlands.,GROW, Maastricht University, Maastricht, The Netherlands.,European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member and United for Metabolic Diseases Member
| | - Didem Demirbas
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kent Lai
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah College of Health, Salt Lake City, UT, USA
| | - Eileen P Treacy
- European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member and United for Metabolic Diseases Member.,National Centre for Inherited Metabolic Disorders, Mater Misericordiae University Hospital, Dublin, Ireland.,School of Medicine, Trinity College, Dublin 2, Ireland.,School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Harvey L Levy
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Louise E Wilkins-Haug
- Division of Maternal Fetal Medicine, Obstetrics and Gynecology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - M Estela Rubio-Gozalbo
- Department of Pediatrics and Clinical Genetics, Maastricht University Medical Centre+, Maastricht, The Netherlands.,GROW, Maastricht University, Maastricht, The Netherlands.,European Reference Network for Hereditary Metabolic Disorders (MetabERN) Member and United for Metabolic Diseases Member
| | - Gerard T Berry
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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Hagen-Lillevik S, Johnson J, Lai K. Early postnatal alterations in follicular stress response and survival in a mouse model of Classic Galactosemia. J Ovarian Res 2022; 15:122. [PMID: 36414970 PMCID: PMC9682695 DOI: 10.1186/s13048-022-01049-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 10/07/2022] [Indexed: 11/24/2022] Open
Abstract
Primary ovarian insufficiency is characterized by accelerated loss of primordial follicles, which results in ovarian failure and concomitant menopause before age 40. About 1-3% of females in the general population are diagnosed with POI; however, greater than 80% of females with the inherited disease Classic Galactosemia will develop POI. Classic Galactosemia is caused by mutations in the GALT gene encoding the enzyme galactose-1 phosphate uridylyltransferase. While dietary restriction of galactose is lifesaving in the neonatal period, the development of complications including primary ovarian insufficiency is not mitigated. Additionally, the pattern(s) of follicle loss have not been completely characterized. The chronic accumulation of aberrant metabolites such as galactose-1-phosphate and galactitol are suspected culprits in the development of the sequelae, yet the mechanisms remain elusive.Our group uses a GalT gene-trapped mouse model to study the pathophysiology of primary ovarian insufficiency in Classic Galactosemia. We recently showed that differences in the Integrated Stress Response pathway occur in mutant ovaries that likely contribute to their primary ovarian insufficiency phenotype. Using immunofluorescent staining of histological sections of ovaries at progressive ages, we saw evidence of altered Integrated Stress Response activity in granulosa cells and primordial oocytes consistent with accelerated primordial follicle growth activation, aberrant DNA damage and/or repair, and increased cellular stress/death. Overall, our findings indicate that abnormal Integrated Stress Response in the Classic Galactosemia model ovary results in accelerated primordial follicle growth activation, sometimes referred to as "burnout." These aberrant early events help further clarify when/how the primary ovarian insufficiency phenotype arises under galactosemic conditions.
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Affiliation(s)
- Synneva Hagen-Lillevik
- grid.223827.e0000 0001 2193 0096Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT 84108 USA ,grid.223827.e0000 0001 2193 0096Department of Nutrition and Integrative Physiology, University of Utah College of Health, 250 South 1850 East Room 214, Salt Lake City, UT 84112 USA
| | - Joshua Johnson
- grid.430503.10000 0001 0703 675XDivision of Reproductive Sciences, Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado Denver (AMC), Building RC2, Room P15 3103, Mail Stop 8613, Aurora, CO 80045 USA
| | - Kent Lai
- grid.223827.e0000 0001 2193 0096Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT 84108 USA ,grid.223827.e0000 0001 2193 0096Department of Nutrition and Integrative Physiology, University of Utah College of Health, 250 South 1850 East Room 214, Salt Lake City, UT 84112 USA
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Novel Gene-Correction-Based Therapeutic Modalities for Monogenic Liver Disorders. Bioengineering (Basel) 2022; 9:bioengineering9080392. [PMID: 36004917 PMCID: PMC9404740 DOI: 10.3390/bioengineering9080392] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/04/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022] Open
Abstract
The majority of monogenic liver diseases are autosomal recessive disorders, with few being sex-related or co-dominant. Although orthotopic liver transplantation (LT) is currently the sole therapeutic option for end-stage patients, such an invasive surgical approach is severely restricted by the lack of donors and post-transplant complications, mainly associated with life-long immunosuppressive regimens. Therefore, the last decade has witnessed efforts for innovative cellular or gene-based therapeutic strategies. Gene therapy is a promising approach for treatment of many hereditary disorders, such as monogenic inborn errors. The liver is an organ characterized by unique features, making it an attractive target for in vivo and ex vivo gene transfer. The current genetic approaches for hereditary liver diseases are mediated by viral or non-viral vectors, with promising results generated by gene-editing tools, such as CRISPR-Cas9 technology. Despite massive progress in experimental gene-correction technologies, limitations in validated approaches for monogenic liver disorders have encouraged researchers to refine promising gene therapy protocols. Herein, we highlighted the most common monogenetic liver disorders, followed by proposed genetic engineering approaches, offered as promising therapeutic modalities.
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Hagen-Lillevik S, Johnson J, Siddiqi A, Persinger J, Hale G, Lai K. Harnessing the Power of Purple Sweet Potato Color and Myo-Inositol to Treat Classic Galactosemia. Int J Mol Sci 2022; 23:ijms23158654. [PMID: 35955788 PMCID: PMC9369367 DOI: 10.3390/ijms23158654] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 01/25/2023] Open
Abstract
Classic Galactosemia (CG) is a devastating inborn error of the metabolism caused by mutations in the GALT gene encoding the enzyme galactose-1 phosphate uridylyltransferase in galactose metabolism. Severe complications of CG include neurological impairments, growth restriction, cognitive delays, and, for most females, primary ovarian insufficiency. The absence of the GALT enzyme leads to an accumulation of aberrant galactose metabolites, which are assumed to be responsible for the sequelae. There is no treatment besides the restriction of dietary galactose, which does not halt the development of the complications; thus, additional treatments are sorely needed. Supplements have been used in other inborn errors of metabolism but are not part of the therapeutic regimen for CG. The goal of this study was to test two generally recognized as safe supplements (purple sweet potato color (PSPC) and myo-inositol (MI)) that may impact cellular pathways contributing to the complications in CG. Our group uses a GalT gene-trapped mouse model to study the pathophysiology in CG, which phenocopy many of the complications. Here we report the ability of PSPC to ameliorate dysregulation in the ovary, brain, and liver of our mutant mice as well as positive results of MI supplementation in the ovary and brain.
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Affiliation(s)
- Synneva Hagen-Lillevik
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84108, USA
- Correspondence: (S.H.-L.); (K.L.); Tel.: +1-253-592-8692 (S.H.-L.)
| | - Joshua Johnson
- Division of Reproductive Sciences, Aurora, CO 80045, USA
- Division of Reproductive Endocrinology and Infertility, Aurora, CO 80045, USA
- Department of Obstetrics and Gynecology, Aurora, CO 80045, USA
| | - Anwer Siddiqi
- College of Medicine, University of Florida, Jacksonville, FL 32209, USA
| | - Jes Persinger
- Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80302, USA
| | - Gillian Hale
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Kent Lai
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84108, USA
- Correspondence: (S.H.-L.); (K.L.); Tel.: +1-253-592-8692 (S.H.-L.)
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9
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Brophy ML, Stansfield JC, Ahn Y, Cheng SH, Murphy JE, Bell RD. AAV-mediated expression of galactose-1-phosphate uridyltransferase corrects defects of galactose metabolism in classic galactosemia patient fibroblasts. J Inherit Metab Dis 2022; 45:481-492. [PMID: 34918784 DOI: 10.1002/jimd.12468] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 11/22/2021] [Accepted: 12/08/2021] [Indexed: 11/10/2022]
Abstract
Classic galactosemia (CG) is a rare disorder of autosomal recessive inheritance. It is caused predominantly by point mutations as well as deletions in the gene encoding the enzyme galactose-1-phosphate uridyltransferase (GALT). The majority of the more than 350 mutations identified in the GALT gene cause a significant reduction in GALT enzyme activity resulting in the toxic buildup of galactose metabolites that in turn is associated with cellular stress and injury. Consequently, developing a therapeutic strategy that reverses both the oxidative and ER stress in CG cells may be helpful in combating this disease. Recombinant adeno-associated virus (AAV)-mediated gene therapy to restore GALT activity offers the potential to address the unmet medical needs of galactosemia patients. Here, utilizing fibroblasts derived from CG patients we demonstrated that AAV-mediated augmentation of GALT protein and activity resulted in the prevention of ER and oxidative stress. We also demonstrate that these CG patient fibroblasts exhibit reduced CD109 and TGFβRII protein levels and that these effectors of cellular homeostasis could be restored following AAV-mediated expression of GALT. Finally, we show initial in vivo proof-of-concept restoration of galactose metabolism in a GALT knockout mouse model following treatment with AAV-GALT.
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Affiliation(s)
- Megan L Brophy
- Rare Disease Research Unit, Pfizer, Inc., Cambridge, Massachusetts, USA
| | - John C Stansfield
- Early Clinical Development, Pfizer, Inc., Cambridge, Massachusetts, USA
| | - Youngwook Ahn
- Target Sciences, Pfizer, Inc., Cambridge, Massachusetts, USA
| | - Seng H Cheng
- Rare Disease Research Unit, Pfizer, Inc., Cambridge, Massachusetts, USA
| | - John E Murphy
- Rare Disease Research Unit, Pfizer, Inc., Cambridge, Massachusetts, USA
| | - Robert D Bell
- Rare Disease Research Unit, Pfizer, Inc., Cambridge, Massachusetts, USA
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10
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Abstract
Accumulation of phosphorylated intermediates during cellular metabolism can have wide-ranging toxic effects on many organisms, including humans and the pathogens that infect them. These toxicities can be induced by feeding an upstream metabolite (a sugar, for instance) while simultaneously blocking the appropriate metabolic pathway with either a mutation or an enzyme inhibitor. Here, we survey the toxicities that can arise in the metabolism of glucose, galactose, fructose, fructose-asparagine, glycerol, trehalose, maltose, mannose, mannitol, arabinose, and rhamnose. Select enzymes in these metabolic pathways may serve as novel therapeutic targets. Some are conserved broadly among prokaryotes and eukaryotes (e.g., glucose and galactose) and are therefore unlikely to be viable drug targets. However, others are found only in bacteria (e.g., fructose-asparagine, rhamnose, and arabinose), and one is found in fungi but not in humans (trehalose). We discuss what is known about the mechanisms of toxicity and how resistance is achieved in order to identify the prospects and challenges associated with targeted exploitation of these pervasive metabolic vulnerabilities.
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11
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Hagen-Lillevik S, Rushing JS, Appiah L, Longo N, Andrews A, Lai K, Johnson J. Pathophysiology and management of classic galactosemic primary ovarian insufficiency. REPRODUCTION AND FERTILITY 2021; 2:R67-R84. [PMID: 35118398 PMCID: PMC8788619 DOI: 10.1530/raf-21-0014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 06/25/2021] [Indexed: 12/14/2022] Open
Abstract
Classic galactosemia is an inborn error of carbohydrate metabolism associated with early-onset primary ovarian insufficiency (POI) in young women. Our understanding of the consequences of galactosemia upon fertility and fecundity of affected women is expanding, but there are important remaining gaps in our knowledge and tools for its management, and a need for continued dialog so that the special features of the condition can be better managed. Here, we review galactosemic POI and its reproductive endocrinological clinical sequelae and summarize current best clinical practices for its management. Special consideration is given to the very early-onset nature of the condition in the pediatric/adolescent patient. Afterward, we summarize our current understanding of the reproductive pathophysiology of galactosemia, including the potential action of toxic galactose metabolites upon the ovary. Our work establishing that ovarian cellular stress reminiscent of endoplasmic reticulum (ER) stress is present in a mouse model of galactosemia, as well as work by other groups, are summarized. LAY SUMMARY Patients with the condition of classic galactosemia need to maintain a strict lifelong diet that excludes the sugar galactose. This is due to having mutations in enzymes that process galactose, resulting in the buildup of toxic metabolic by-products of the sugar. Young women with classic galactosemia often lose the function of their ovaries very early in life (termed 'primary ovarian insufficiency'), despite adherence to a galactose-restricted diet. This means that in addition to the consequences of the disease, these women also face infertility and the potential need for hormone replacement therapy. This article summarizes current strategies for managing the care of galactosemic girls and women and also what is known of how the condition leads to early primary ovarian insufficiency.
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Affiliation(s)
- Synneva Hagen-Lillevik
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Nutrition and Integrative Physiology, University of Utah College of Health, Salt Lake City, Utah, USA
| | - John S Rushing
- Divisions of Reproductive Sciences, Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado Denver (AMC), Aurora, Colorado, USA
| | - Leslie Appiah
- Division of General Obstetrics and Gynecology, Department of Obstetrics and Gynecology, University of Colorado Denver (AMC), Anschutz Outpatient Pavilion, Aurora, Colorado, USA
| | - Nicola Longo
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Nutrition and Integrative Physiology, University of Utah College of Health, Salt Lake City, Utah, USA
| | - Ashley Andrews
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Kent Lai
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Nutrition and Integrative Physiology, University of Utah College of Health, Salt Lake City, Utah, USA
| | - Joshua Johnson
- Divisions of Reproductive Sciences, Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado Denver (AMC), Aurora, Colorado, USA
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Banford S, McCorvie TJ, Pey AL, Timson DJ. Galactosemia: Towards Pharmacological Chaperones. J Pers Med 2021; 11:jpm11020106. [PMID: 33562227 PMCID: PMC7914515 DOI: 10.3390/jpm11020106] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 02/07/2023] Open
Abstract
Galactosemia is a rare inherited metabolic disease resulting from mutations in the four genes which encode enzymes involved in the metabolism of galactose. The current therapy, the removal of galactose from the diet, is inadequate. Consequently, many patients suffer lifelong physical and cognitive disability. The phenotype varies from almost asymptomatic to life-threatening disability. The fundamental biochemical cause of the disease is a decrease in enzymatic activity due to failure of the affected protein to fold and/or function correctly. Many novel therapies have been proposed for the treatment of galactosemia. Often, these are designed to treat the symptoms and not the fundamental cause. Pharmacological chaperones (PC) (small molecules which correct the folding of misfolded proteins) represent an exciting potential therapy for galactosemia. In theory, they would restore enzyme function, thus preventing downstream pathological consequences. In practice, no PCs have been identified for potential application in galactosemia. Here, we review the biochemical basis of the disease, identify opportunities for the application of PCs and describe how these might be discovered. We will conclude by considering some of the clinical issues which will affect the future use of PCs in the treatment of galactosemia.
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Affiliation(s)
- Samantha Banford
- South Eastern Health and Social Care Trust, Downpatrick BT30 6RL, UK;
| | - Thomas J. McCorvie
- Structural Genomics Consortium, University of Oxford, Oxford OX3 7DQ, UK;
| | - Angel L. Pey
- Departamento de Química Física, Unidad de Excelencia de Química aplicada a Biomedicina y Medioambiente e Instituto de Biotecnología, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain;
| | - David J. Timson
- School of Pharmacy and Biomolecular Sciences, The University of Brighton, Brighton BN2 4GJ, UK
- Correspondence:
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Delnoy B, Coelho AI, Rubio-Gozalbo ME. Current and Future Treatments for Classic Galactosemia. J Pers Med 2021; 11:jpm11020075. [PMID: 33525536 PMCID: PMC7911353 DOI: 10.3390/jpm11020075] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/23/2021] [Accepted: 01/24/2021] [Indexed: 02/07/2023] Open
Abstract
Type I (classic) galactosemia, galactose 1-phosphate uridylyltransferase (GALT)-deficiency is a hereditary disorder of galactose metabolism. The current therapeutic standard of care, a galactose-restricted diet, is effective in treating neonatal complications but is inadequate in preventing burdensome complications. The development of several animal models of classic galactosemia that (partly) mimic the biochemical and clinical phenotypes and the resolution of the crystal structure of GALT have provided important insights; however, precise pathophysiology remains to be elucidated. Novel therapeutic approaches currently being explored focus on several of the pathogenic factors that have been described, aiming to (i) restore GALT activity, (ii) influence the cascade of events and (iii) address the clinical picture. This review attempts to provide an overview on the latest advancements in therapy approaches.
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Affiliation(s)
- Britt Delnoy
- Department of Pediatrics, Maastricht University Medical Centre, 6229 HX Maastricht, The Netherlands; (B.D.); (A.I.C.)
- Department of Clinical Genetics, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
- GROW-School for Oncology and Developmental Biology, Maastricht University, 6229 HX Maastricht, The Netherlands
| | - Ana I. Coelho
- Department of Pediatrics, Maastricht University Medical Centre, 6229 HX Maastricht, The Netherlands; (B.D.); (A.I.C.)
| | - Maria Estela Rubio-Gozalbo
- Department of Pediatrics, Maastricht University Medical Centre, 6229 HX Maastricht, The Netherlands; (B.D.); (A.I.C.)
- Department of Clinical Genetics, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
- GROW-School for Oncology and Developmental Biology, Maastricht University, 6229 HX Maastricht, The Netherlands
- Correspondence: ; Tel.: +31-43-3872920
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14
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Gut microbiota changes in patients with autism spectrum disorders. J Psychiatr Res 2020; 129:149-159. [PMID: 32912596 DOI: 10.1016/j.jpsychires.2020.06.032] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/26/2020] [Accepted: 06/30/2020] [Indexed: 12/26/2022]
Abstract
Autism spectrum disorder (ASD) has a high incidence of intestinal comorbidity, indicating a strong association with gut microbiota. The purpose of this study was to characterize gut microbiota profiles in children with ASD. Seventy-seven children with ASD [33 with mild ASD and 44 with severe ASD according to the Childhood Autism Rating Scale score] and 50 age-matched healthy children were enrolled. Compared with children in the healthy control (HC) group, those in the ASD group showed higher biomass, richness, and biodiversity of gut microbiota, and an altered microbial community structure. At the genus level, there was a significant increase in the relative abundance of unidentified Lachnospiraceae, Clostridiales, Erysipelotrichaceae, Dorea, Collinsella, and Lachnoclostridium, whereas Bacteroides, Faecalibacterium, Parasutterella, and Paraprevotella were significantly lower in the ASD group than in the control group. The presence of unidentified Erysipelotrichaceae, Faecalibacterium, and Lachnospiraceae was positively correlated with ASD severity. Notably, three microbial markers (Faecalitalea, Caproiciproducens and Collinsella) were identified in a random forest model with an area under the curve (AUC) of 0.94 for differentiation between HCs and ASD patients. Furthermore, the validation model was consistent with the discovery set (AUC = 0.98, 95% CI: 97.9%-100%). The training and testing sets were more effective when the number of bacteria was increased. In addition, the functional properties (such as galactose metabolism, glycosyltransferase activity, and glutathione metabolism) displayed significant differences between the ASD and HC groups. The current study provides evidence for the relationship between gut microbiota and ASD, with the findings suggesting that gut microbiota could contribute to symptomology. Thus, modulation of gut microbiota may be a new therapeutic strategy for ASD.
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15
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A Great Catch for Investigating Inborn Errors of Metabolism-Insights Obtained from Zebrafish. Biomolecules 2020; 10:biom10091352. [PMID: 32971894 PMCID: PMC7564250 DOI: 10.3390/biom10091352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/18/2020] [Accepted: 09/19/2020] [Indexed: 12/14/2022] Open
Abstract
Inborn errors of metabolism cause abnormal synthesis, recycling, or breakdown of amino acids, neurotransmitters, and other various metabolites. This aberrant homeostasis commonly causes the accumulation of toxic compounds or depletion of vital metabolites, which has detrimental consequences for the patients. Efficient and rapid intervention is often key to survival. Therefore, it requires useful animal models to understand the pathomechanisms and identify promising therapeutic drug targets. Zebrafish are an effective tool to investigate developmental mechanisms and understanding the pathophysiology of disorders. In the past decades, zebrafish have proven their efficiency for studying genetic disorders owing to the high degree of conservation between human and zebrafish genes. Subsequently, several rare inherited metabolic disorders have been successfully investigated in zebrafish revealing underlying mechanisms and identifying novel therapeutic targets, including methylmalonic acidemia, Gaucher’s disease, maple urine disorder, hyperammonemia, TRAPPC11-CDGs, and others. This review summarizes the recent impact zebrafish have made in the field of inborn errors of metabolism.
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Rasmussen SA, Daenzer JMI, MacWilliams JA, Head ST, Williams MB, Geurts AM, Schroeder JP, Weinshenker D, Fridovich‐Keil JL. A galactose-1-phosphate uridylyltransferase-null rat model of classic galactosemia mimics relevant patient outcomes and reveals tissue-specific and longitudinal differences in galactose metabolism. J Inherit Metab Dis 2020; 43:518-528. [PMID: 31845342 PMCID: PMC7318568 DOI: 10.1002/jimd.12205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 12/04/2019] [Accepted: 12/11/2019] [Indexed: 12/14/2022]
Abstract
Classic galactosemia (CG) is a potentially lethal inborn error of metabolism, if untreated, that results from profound deficiency of galactose-1-phosphate uridylyltransferase (GALT), the middle enzyme of the Leloir pathway of galactose metabolism. While newborn screening and rapid dietary restriction of galactose prevent or resolve the potentially lethal acute symptoms of CG, by mid-childhood, most treated patients experience significant complications. The mechanisms underlying these long-term deficits remain unclear. Here we introduce a new GALT-null rat model of CG and demonstrate that these rats display cataracts, cognitive, motor, and growth phenotypes reminiscent of patients outcomes. We further apply the GALT-null rats to test how well blood biomarkers, typically followed in patients, reflect metabolic perturbations in other, more relevant tissues. Our results document that the relative levels of galactose metabolites seen in GALT deficiency differ widely by tissue and age, and that red blood cell Gal-1P, the marker most commonly followed in patients, shows no significant association with Gal-1P in other tissues. The work reported here establishes our outbred GALT-null rats as an effective model for at least four complications characteristic of CG, and sets the stage for future studies addressing mechanism and testing the efficacy of novel candidate interventions.
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Affiliation(s)
- Shauna A. Rasmussen
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
| | - Jennifer M. I. Daenzer
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
| | - Jessica A. MacWilliams
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
| | - S. Taylor Head
- Rollins School of Public Health, Graduate Program in BiostatisticsEmory UniversityAtlantaGeorgia
| | - Martine B. Williams
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
| | - Aron M. Geurts
- Gene Editing Rat Resource CenterMedical College of WisconsinMilwaukeeWisconsin
| | - Jason P. Schroeder
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
| | - David Weinshenker
- Department of Human GeneticsEmory University School of Medicine, Emory UniversityAtlantaGeorgia
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Haskovic M, Coelho AI, Bierau J, Vanoevelen JM, Steinbusch LKM, Zimmermann LJI, Villamor‐Martinez E, Berry GT, Rubio‐Gozalbo ME. Pathophysiology and targets for treatment in hereditary galactosemia: A systematic review of animal and cellular models. J Inherit Metab Dis 2020; 43:392-408. [PMID: 31808946 PMCID: PMC7317974 DOI: 10.1002/jimd.12202] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/25/2019] [Accepted: 12/03/2019] [Indexed: 12/18/2022]
Abstract
Since the first description of galactosemia in 1908 and despite decades of research, the pathophysiology is complex and not yet fully elucidated. Galactosemia is an inborn error of carbohydrate metabolism caused by deficient activity of any of the galactose metabolising enzymes. The current standard of care, a galactose-restricted diet, fails to prevent long-term complications. Studies in cellular and animal models in the past decades have led to an enormous progress and advancement of knowledge. Summarising current evidence in the pathophysiology underlying hereditary galactosemia may contribute to the identification of treatment targets for alternative therapies that may successfully prevent long-term complications. A systematic review of cellular and animal studies reporting on disease complications (clinical signs and/or biochemical findings) and/or treatment targets in hereditary galactosemia was performed. PubMed/MEDLINE, EMBASE, and Web of Science were searched, 46 original articles were included. Results revealed that Gal-1-P is not the sole pathophysiological agent responsible for the phenotype observed in galactosemia. Other currently described contributing factors include accumulation of galactose metabolites, uridine diphosphate (UDP)-hexose alterations and subsequent impaired glycosylation, endoplasmic reticulum (ER) stress, altered signalling pathways, and oxidative stress. galactokinase (GALK) inhibitors, UDP-glucose pyrophosphorylase (UGP) up-regulation, uridine supplementation, ER stress reducers, antioxidants and pharmacological chaperones have been studied, showing rescue of biochemical and/or clinical symptoms in galactosemia. Promising co-adjuvant therapies include antioxidant therapy and UGP up-regulation. This systematic review provides an overview of the scattered information resulting from animal and cellular studies performed in the past decades, summarising the complex pathophysiological mechanisms underlying hereditary galactosemia and providing insights on potential treatment targets.
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Affiliation(s)
- Minela Haskovic
- Department of PediatricsMaastricht University Medical Center+MaastrichtThe Netherlands
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
| | - Ana I. Coelho
- Department of PediatricsMaastricht University Medical Center+MaastrichtThe Netherlands
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
| | - Jörgen Bierau
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
| | - Jo M. Vanoevelen
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
| | - Laura K. M. Steinbusch
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
| | - Luc J. I. Zimmermann
- Department of PediatricsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
| | - Eduardo Villamor‐Martinez
- Department of PediatricsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
| | - Gerard T. Berry
- The Manton Center for Orphan Disease Research, Division of Genetics and GenomicsBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - M. Estela Rubio‐Gozalbo
- Department of PediatricsMaastricht University Medical Center+MaastrichtThe Netherlands
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW‐School for Oncology and Developmental Biology, Maastricht UniversityMaastrichtThe Netherlands
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Fluorinated Galactoses Inhibit Galactose-1-Phosphate Uridyltransferase and Metabolically Induce Galactosemia-like Phenotypes in HEK-293 Cells. Cells 2020; 9:cells9030607. [PMID: 32138379 PMCID: PMC7140460 DOI: 10.3390/cells9030607] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/19/2020] [Accepted: 02/27/2020] [Indexed: 01/24/2023] Open
Abstract
Genetic defects of human galactose-1-phosphate uridyltransferase (hGALT) and the partial loss of enzyme function result in an altered galactose metabolism with serious long-term developmental impairment of organs in classic galactosemia patients. In search for cellular pathomechanisms induced by the stressor galactose, we looked for ways to induce metabolically a galactosemia-like phenotype by hGALT inhibition in HEK293 cells. In kinetic studies, we provide evidence for 2-fluorinated galactose-1-phosphate (F-Gal-1-P) to competitively inhibit recombinant hGALT with a KI of 0.9 mM. Contrasting with hepatic cells, no alterations of N-glycoprofiles in MIG (metabolic induction of galactosemia)-HEK293 cells were revealed for an inducible secretory netrin-1 probe by MALDI-MS. Differential fluorescence-activated cell sorting demonstrated reduced surface expression of N-glycosylated CD109, EGFR, DPP4, and rhMUC1. Membrane raft proteomes exhibited dramatic alterations pointing to an affection of the unfolded protein response, and of targeted protein traffick. Most prominent, a negative regulation of oxidative stress was revealed presumably as a response to a NADPH pool depletion during reduction of Gal/F-Gal. Cellular perturbations induced by fluorinated galactoses in normal epithelial cells resemble proteomic changes revealed for galactosemic fibroblasts. In conclusion, the metabolic induction of galactosemia-like phenotypes in healthy epithelial/neuronal cells could support studies on the molecular pathomechanisms in classic galactosemia, in particular under conditions of low galactose stress and residual GALT activity.
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19
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Affiliation(s)
- David J. Timson
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
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20
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Insights into the Pathophysiology of Infertility in Females with Classical Galactosaemia. Int J Mol Sci 2019; 20:ijms20205236. [PMID: 31652573 PMCID: PMC6834160 DOI: 10.3390/ijms20205236] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/14/2019] [Accepted: 10/16/2019] [Indexed: 11/26/2022] Open
Abstract
Classical galactosaemia (CG) (OMIM 230400) is a rare inborn error of galactose metabolism caused by the deficiency of the enzyme galactose-1-phosphate uridylyltransferase (GALT, EC 2.7.7.12). Primary ovarian insufficiency (POI) is the most common long-term complication experienced by females with CG, presenting with hypergonadotrophic hypoestrogenic infertility affecting at least 80% of females despite new-born screening and lifelong galactose dietary restriction. In this review, we describe the hypothesized pathophysiology of POI from CG, implications of timing of the ovarian dysfunction, and the new horizons and future prospects for treatments and fertility preservation.
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Balakrishnan B, An D, Nguyen V, DeAntonis C, Martini PGV, Lai K. Novel mRNA-Based Therapy Reduces Toxic Galactose Metabolites and Overcomes Galactose Sensitivity in a Mouse Model of Classic Galactosemia. Mol Ther 2019; 28:304-312. [PMID: 31604675 DOI: 10.1016/j.ymthe.2019.09.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/04/2019] [Accepted: 09/12/2019] [Indexed: 11/19/2022] Open
Abstract
Classic galactosemia (CG) is a potentially lethal inborn error of galactose metabolism that results from deleterious mutations in the human galactose-1 phosphate uridylyltransferase (GALT) gene. Previously, we constructed a GalT-/- (GalT-deficient) mouse model that exhibits galactose sensitivity in the newborn mutant pups, reduced fertility in adult females, impaired motor functions, and growth restriction in both sexes. In this study, we tested whether restoration of hepatic GALT activity alone could decrease galactose-1 phosphate (gal-1P) and plasma galactose in the mouse model. The administration of different doses of mouse GalT (mGalT) mRNA resulted in a dose-dependent increase in mGalT protein expression and enzyme activity in the liver of GalT-deficient mice. Single intravenous (i.v.) dose of human GALT (hGALT) mRNA decreased gal-1P in mutant mouse liver and red blood cells (RBCs) within 24 h with low levels maintained for over a week. Repeated i.v. injections increased hepatic GalT expression, nearly normalized gal-1P levels in liver, and decreased gal-1P levels in RBCs and peripheral tissues throughout all doses. Moreover, repeated dosing reduced plasma galactose by 60% or more throughout all four doses. Additionally, a single intraperitoneal dose of hGALT mRNA overcame the galactose sensitivity and promoted the growth in a GalT-/- newborn pup.
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Affiliation(s)
- Bijina Balakrishnan
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA
| | - Ding An
- Moderna, Inc., Cambridge, MA 02139, USA
| | - Vi Nguyen
- Moderna, Inc., Cambridge, MA 02139, USA
| | | | | | - Kent Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA.
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22
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Balakrishnan B, Siddiqi A, Mella J, Lupo A, Li E, Hollien J, Johnson J, Lai K. Salubrinal enhances eIF2α phosphorylation and improves fertility in a mouse model of Classic Galactosemia. Biochim Biophys Acta Mol Basis Dis 2019; 1865:165516. [PMID: 31362041 DOI: 10.1016/j.bbadis.2019.07.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/15/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022]
Abstract
Loss of galactose-1 phosphate uridylyltransferase (GALT) activity in humans results in Classic Galactosemia, and the GalT-deficient (GalT-/-) mouse mimics the patient condition. GalT-/- ovaries display elevated endoplasmic reticulum (ER) stress marker, BiP, and downregulated canonical phosphatidylinositol 3-kinase (Pi3k)/protein kinase B (Akt) growth/pro-survival signaling. Numbers of primordial follicles are reduced in the mutants, recapitulating the accelerated ovarian aging seen in human patients. We previously found that oral administration of the compound Salubrinal (an eIF2α phosphatase inhibitor), resulted in reduction of ovarian BiP expression, rescued Pi3k/Akt signaling, and a doubling of primordial follicles in GalT-/- adults. Here, we further characterized galactosemic stress in GalT-/- mice versus wild-type (WT) controls, and examined whether Salubrinal treatment improved broader reproductive parameters. We assessed the expression levels of factors of the unfolded protein response (UPR), and found that BiP, phospho-Perk, and phospho-eIF2α were all elevated in GalT-/- ovaries. However, neither IKK activation (NFκB pathway) nor alternative Xbp1 splicing downstream of ER membrane protein Ire1α activation was induced, suggesting an Xbp1-independent UPR in galactosemic stress. Moreover, Salubrinal treatment significantly increased the number of ovulated eggs in mutant animals after gonadotrophic superovulation. Salubrinal treatment also normalized estrus cycle stage lengths and resulted in significantly larger litter sizes than vehicle-treated mutants. Overall, we show that Salubrinal protects against galactosemia-induced primordial follicle loss in a fashion that includes suppressing the de-phosphorylation of eIF2α, and that intervention in this way significantly improves and extends ovarian function, fertility, and fecundity.
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Affiliation(s)
- B Balakrishnan
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - A Siddiqi
- Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, United States
| | - J Mella
- School of Biological Sciences, University of Utah College of Science, United States
| | - A Lupo
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - E Li
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - J Hollien
- School of Biological Sciences, University of Utah College of Science, United States
| | - J Johnson
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado, United States.
| | - K Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States.
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Fischer ST, Frederick AB, Tran V, Li S, Jones DP, Fridovich-Keil JL. Metabolic perturbations in classic galactosemia beyond the Leloir pathway: Insights from an untargeted metabolomic study. J Inherit Metab Dis 2019; 42:254-263. [PMID: 30667068 PMCID: PMC6414239 DOI: 10.1002/jimd.12007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 09/23/2018] [Accepted: 09/24/2018] [Indexed: 01/06/2023]
Abstract
Classic galactosemia (CG) is an autosomal recessive disorder that impacts close to 1/50000 live births in the United States, with varying prevalence in other countries. Following exposure to milk, which contains high levels of galactose, affected infants may experience rapid onset and progression of potentially lethal symptoms. With the benefit of early diagnosis, generally by newborn screening, and immediate and lifelong dietary restriction of galactose, the acute sequelae of disease can be prevented or resolved. However, long-term complications are common, and despite many decades of research, the bases of these complications remain unexplained. As a step toward defining the underlying pathophysiology of long-term outcomes in CG, we applied an untargeted metabolomic approach with mass spectrometry and dual liquid chromatography, comparing thousands of small molecules in plasma samples from 183 patients and 31 controls. All patients were on galactose-restricted diets. Using both univariate and multivariate statistical methods, we identified 252 differentially abundant features from anion exchange chromatography and 167 differentially abundant features from C18 chromatography. Mapping these discriminatory features to putative metabolites and biochemical pathways revealed 14 significantly perturbed pathways; these included multiple redox, amino acid, and mitochondrial pathways, among others. Finally, we tested whether any discriminatory features also distinguished cases with mild vs more severe long-term outcomes and found multiple candidates, of which one achieved false discovery rate-adjusted q < 0.1. These results extend substantially from prior targeted studies of metabolic perturbation in CG and offer a new approach to identifying candidate modifiers and targets for intervention.
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Affiliation(s)
- S. Taylor Fischer
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Allison B. Frederick
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - ViLinh Tran
- Clinical Biomarkers Laboratory, Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA USA
| | - Shuzhao Li
- Clinical Biomarkers Laboratory, Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA USA
| | - Dean P. Jones
- Clinical Biomarkers Laboratory, Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA USA
| | - Judith L. Fridovich-Keil
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
- Correspondence to: Judith L. Fridovich-Keil, Department of Human Genetics, Emory University School of Medicine, Rm. 325.2 Whitehead Bldg., 615 Michael St, Atlanta, GA 30322 TEL 404-727-3924, FAX 404-727-3949,
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24
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Yuzyuk T, Balakrishnan B, Schwarz EL, De Biase I, Hobert J, Longo N, Mao R, Lai K, Pasquali M. Effect of genotype on galactose-1-phosphate in classic galactosemia patients. Mol Genet Metab 2018; 125:258-265. [PMID: 30172461 DOI: 10.1016/j.ymgme.2018.08.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 11/27/2022]
Abstract
Impaired activity of galactose-1-phosphate uridyltransferase (GALT) causes classic galactosemia (OMIM 230400), characterized by the accumulation of galactose-1-phosphate (GAL1P) in patients' red blood cells (RBCs). Our recent study demonstrated a correlation between RBC GAL1P and long-term outcomes in galactosemia patients. Here, we analyze biochemical and molecular results in 77 classic galactosemia patients to evaluate the association between GALT genotypes and GAL1P concentration in RBCs. Experimental data from model organisms were also included to assess the correlation between GAL1P and predicted residual activity of each genotype. Although all individuals in this study showed markedly reduced RBC GALT activity, we observed significant differences in RBC GAL1P concentrations among galactosemia genotypes. While levels of GAL1P on treatment did not correlate with RBC GALT activities (p = 0.166), there was a negative nonlinear correlation between mean GAL1P concentrations and predicted residual enzyme activity of genotype (p = 0.004). These studies suggest that GAL1P levels in RBCs on treatment likely reflect the overall functional impairment of GALT in patients with galactosemia.
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Affiliation(s)
- Tatiana Yuzyuk
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA.
| | - Bijina Balakrishnan
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
| | | | - Irene De Biase
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA
| | - Judith Hobert
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA
| | - Nicola Longo
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Rong Mao
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA
| | - Kent Lai
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Marzia Pasquali
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA
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25
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Schuler D, Höll C, Grün N, Ulrich J, Dillner B, Klebl F, Ammon A, Voll LM, Kämper J. Galactose metabolism and toxicity in Ustilago maydis. Fungal Genet Biol 2018; 114:42-52. [PMID: 29580862 DOI: 10.1016/j.fgb.2018.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/07/2018] [Accepted: 03/22/2018] [Indexed: 10/17/2022]
Abstract
In most organisms, galactose is metabolized via the Leloir pathway, which is conserved from bacteria to mammals. Utilization of galactose requires a close interplay of the metabolic enzymes, as misregulation or malfunction of individual components can lead to the accumulation of toxic intermediate compounds. For the phytopathogenic basidiomycete Ustilago maydis, galactose is toxic for wildtype strains, i.e. leads to growth repression despite the presence of favorable carbon sources as sucrose. The galactose sensitivity can be relieved by two independent modifications: (1) by disruption of Hxt1, which we identify as the major transporter for galactose, and (2) by a point mutation in the gene encoding the galactokinase Gal1, the first enzyme of the Leloir pathway. The mutation in gal1(Y67F) leads to reduced enzymatic activity of Gal1 and thus may limit the formation of putatively toxic galactose-1-phosphate. However, systematic deletions and double deletions of different genes involved in galactose metabolism point to a minor role of galactose-1-phosphate in galactose toxicity. Our results show that molecular triggers for galactose toxicity in U. maydis differ from yeast and mammals.
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Affiliation(s)
- David Schuler
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany
| | - Christina Höll
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany
| | - Nathalie Grün
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany
| | - Jonas Ulrich
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany
| | - Bastian Dillner
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany
| | - Franz Klebl
- FAU Erlangen-Nuremberg, Department of Biology, Molecular Plant Physiology, Staudtstrasse 5, 91058 Erlangen, Germany
| | - Alexandra Ammon
- Philips-University of Marburg, Department of Biology, Plant Physiology and Photo Biology, Karl von Frisch Strasse 8, 35043 Marburg, Germany
| | - Lars M Voll
- Philips-University of Marburg, Department of Biology, Plant Physiology and Photo Biology, Karl von Frisch Strasse 8, 35043 Marburg, Germany
| | - Jörg Kämper
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, Fritz Haber Weg 4, 76131 Karlsruhe, Germany.
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26
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Yuzyuk T, Viau K, Andrews A, Pasquali M, Longo N. Biochemical changes and clinical outcomes in 34 patients with classic galactosemia. J Inherit Metab Dis 2018; 41:197-208. [PMID: 29350350 DOI: 10.1007/s10545-018-0136-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/19/2017] [Accepted: 01/02/2018] [Indexed: 10/18/2022]
Abstract
Impaired activity of galactose-1-phosphate uridyltransferase (GALT) causes galactosemia, an autosomal recessive disorder of galactose metabolism. Early initiation of a galactose-restricted diet can prevent or resolve neonatal complications. Despite therapy, patients often experience long-term complications including speech impairment, learning disabilities, and premature ovarian insufficiency in females. This study evaluates clinical outcomes in 34 galactosemia patients with markedly reduced GALT activity and compares outcomes between patients with different levels of mean galactose-1-phosphate in red blood cells (GAL1P) using logistic regression: group 1 (n = 13) GAL1P ≤1.7 mg/dL vs. group 2 (n = 21) GAL1P ≥ 2 mg/dL. Acute symptoms at birth were comparable between groups (p = 0.30) with approximately 50% of patients presenting with jaundice, liver failure, and failure-to-thrive. However, group 2 patients had significantly higher prevalence of negative long-term outcomes compared to group 1 patients (p = 0.01). Only one of 11 patients >3 yo in group 1 developed neurological and severe behavioral problems of unclear etiology. In contrast, 17 of 20 patients >3 yo in group 2 presented with one or more long-term complications associated with galactosemia. The majority of females ≥15 yo in this group also had impaired ovarian function with markedly reduced levels of anti-Müllerian hormone. These findings suggest that galactosemia patients with higher GAL1P levels are more likely to have negative long-term outcome. Therefore, evaluation of GAL1P levels on a galactose-restricted diet might be helpful in providing a prognosis for galactosemia patients with rare or novel genotypes whose clinical presentations are not well known.
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Affiliation(s)
- Tatiana Yuzyuk
- Department of Pathology, University of Utah, Salt Lake City, UT, USA.
- ARUP Laboratories, 500 Chipeta Way, Salt Lake City, UT, 84108, USA.
| | - Krista Viau
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
- Boston Children's Hospital, Boston, MA, USA
| | - Ashley Andrews
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Marzia Pasquali
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
- ARUP Laboratories, 500 Chipeta Way, Salt Lake City, UT, 84108, USA
| | - Nicola Longo
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
- ARUP Laboratories, 500 Chipeta Way, Salt Lake City, UT, 84108, USA
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
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27
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Vanoevelen JM, van Erven B, Bierau J, Huang X, Berry GT, Vos R, Coelho AI, Rubio-Gozalbo ME. Impaired fertility and motor function in a zebrafish model for classic galactosemia. J Inherit Metab Dis 2018; 41:117-127. [PMID: 28913702 PMCID: PMC5786655 DOI: 10.1007/s10545-017-0071-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/16/2017] [Accepted: 07/03/2017] [Indexed: 01/28/2023]
Abstract
Classic galactosemia is a genetic disorder of galactose metabolism, caused by severe deficiency of galactose-1-phosphate uridylyltransferase (GALT) enzyme activity due to mutations of the GALT gene. Its pathogenesis is still not fully elucidated, and a therapy that prevents chronic impairments is lacking. In order to move research forward, there is a high need for a novel animal model, which allows organ studies throughout development and high-throughput screening of pharmacologic compounds. Here, we describe the generation of a galt knockout zebrafish model and present its phenotypical characterization. Using a TALEN approach, a galt knockout line was successfully created. Accordingly, biochemical assays confirm essentially undetectable galt enzyme activity in homozygotes. Analogous to humans, galt knockout fish accumulate galactose-1-phosphate upon exposure to exogenous galactose. Furthermore, without prior exposure to exogenous galactose, they exhibit reduced motor activity and impaired fertility (lower egg quantity per mating, higher number of unsuccessful crossings), resembling the human phenotype(s) of neurological sequelae and subfertility. In conclusion, our galt knockout zebrafish model for classic galactosemia mimics the human phenotype(s) at biochemical and clinical levels. Future studies in our model will contribute to improved understanding and management of this disorder.
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Affiliation(s)
- Jo M Vanoevelen
- Department of Clinical Genetics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands.
- GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands.
| | - Britt van Erven
- Department of Clinical Genetics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands
- GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
- Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Jörgen Bierau
- Department of Clinical Genetics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands
| | - Xiaoping Huang
- The Manton Center for Orphan Disease Research, Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Gerard T Berry
- The Manton Center for Orphan Disease Research, Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Rein Vos
- Department of Methodology and Statistics, School for Public Health and Primary Care (CAPHRI), Maastricht University, Maastricht, The Netherlands
| | - Ana I Coelho
- Department of Clinical Genetics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands
- GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
- Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - M Estela Rubio-Gozalbo
- Department of Clinical Genetics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands.
- GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands.
- Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.
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28
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Thakur M, Feldman G, Puscheck EE. Primary ovarian insufficiency in classic galactosemia: current understanding and future research opportunities. J Assist Reprod Genet 2017; 35:3-16. [PMID: 28932969 DOI: 10.1007/s10815-017-1039-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/03/2017] [Indexed: 02/06/2023] Open
Abstract
Classic galactosemia is an inborn error of the metabolism with devastating consequences. Newborn screening has been successful in markedly reducing the acute neonatal symptoms from this disorder. The dramatic response to dietary treatment is one of the major success stories of newborn screening. However, as children with galactosemia achieve adulthood, they face long-term complications. A majority of women with classic galactosemia develop primary ovarian insufficiency and resulting morbidity. The underlying pathophysiology of this complication is not clear. This review focuses on the reproductive issues seen in girls and women with classic galactosemia. Literature on the effects of classic galactosemia on the female reproductive system was reviewed by an extensive Pubmed search (publications from January 1975 to January 2017) using the keywords: galactosemia, ovarian function/dysfunction, primary ovarian insufficiency/failure, FSH, oxidative stress, fertility preservation. In addition, articles cited in the search articles and literature known to the authors was also included in the review. Our understanding of the role of galactose metabolism in the ovary is limited and the pathogenic mechanisms involved in causing primary ovarian insufficiency are unclear. The relative rarity of galactosemia makes it difficult to accumulate data to determine factors defining timing of ovarian dysfunction or treatment/fertility preservation options for this group of women. In this review, we present reproductive challenges faced by women with classic galactosemia, highlight the gaps in our understanding of mechanisms leading to primary ovarian insufficiency in this population, discuss new advances in fertility preservation options, and recommend collaboration between reproductive medicine and metabolic specialists to improve fertility in these women.
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Affiliation(s)
- Mili Thakur
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, 48201, USA. .,Division of Genetic, Genomic and Metabolic Disorders, Department of Pediatrics and Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, 48201, USA. .,The Fertility Center, 3230 Eagle Park Dr. NE, Suite 100, Grand Rapids, MI, 49525, USA.
| | - Gerald Feldman
- Division of Genetic, Genomic and Metabolic Disorders, Department of Pediatrics and Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, 48201, USA.,Department of Pathology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Elizabeth E Puscheck
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, 48201, USA
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29
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Balakrishnan B, Nicholas C, Siddiqi A, Chen W, Bales E, Feng M, Johnson J, Lai K. Reversal of aberrant PI3K/Akt signaling by Salubrinal in a GalT-deficient mouse model. Biochim Biophys Acta Mol Basis Dis 2017; 1863:3286-3293. [PMID: 28844959 DOI: 10.1016/j.bbadis.2017.08.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 08/10/2017] [Accepted: 08/14/2017] [Indexed: 10/19/2022]
Abstract
Classic Galactosemia is an autosomal recessive disorder caused by deleterious mutations in the GALT gene, which encodes galactose-1 phosphate uridylyltransferase enzyme (GALT: EC 2.7.7.12). Recent studies of primary skin fibroblasts isolated from the GalT-deficient mice demonstrated a slower growth rate, a higher level of endoplasmic reticulum (ER) stress, and down-regulation of the Phosphoinositide 3 kinase/Protein kinase B (PI3K/Akt) signaling pathway. In this study, we compared the expression levels of the PI3K/Akt signaling pathway in normal and GalT-deficient mouse tissues. In mutant mouse ovaries, phospho-Akt [pAkt (Ser473)] and pGsk3β were reduced by 62.5% and 93.5%, respectively (p<0.05 versus normal controls). In mutant cerebella, pAkt (Ser473) and pGsk3β were reduced by 62%, 50%, respectively (p<0.05). To assess the role of ER stress in the down-regulation of PI3K/Akt signaling, we examined if administration of Salubrinal, a chemical compound that alleviates ER stress, to GalT-deficient fibroblasts and animals could normalize the pathway. Our results demonstrated that Salubrinal effectively reversed the down-regulated PI3K/Akt signaling pathway in the mutant cells and animals to levels close to those of their normal counterparts. Moreover, we revealed that Salubrinal can significantly slow down the loss of Purkinje cells in the cerebella, as well as the premature loss of primordial ovarian follicles in young mutant mice. These results open the door for a new therapeutic approach for the patients with Classic Galactosemia.
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Affiliation(s)
- B Balakrishnan
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - C Nicholas
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado, United States
| | - A Siddiqi
- Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, United States
| | - W Chen
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - E Bales
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado, United States
| | - M Feng
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States
| | - J Johnson
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado, United States.
| | - K Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, United States.
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30
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van Erven B, Berry GT, Cassiman D, Connolly G, Forga M, Gautschi M, Gubbels CS, Hollak CEM, Janssen MC, Knerr I, Labrune P, Langendonk JG, Õunap K, Thijs A, Vos R, Wortmann SB, Rubio-Gozalbo ME. Fertility in adult women with classic galactosemia and primary ovarian insufficiency. Fertil Steril 2017; 108:168-174. [PMID: 28579413 DOI: 10.1016/j.fertnstert.2017.05.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 04/28/2017] [Accepted: 05/08/2017] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To study pregnancy chance in adult women with classic galactosemia and primary ovarian insufficiency. Despite dietary treatment, >90% of women with classic galactosemia develop primary ovarian insufficiency, resulting in impaired fertility. For many years, chance of spontaneous conception has not been considered, leading to counseling for infertility. But an increasing number of reports on pregnancies in this group questions whether current counseling approaches are correct. DESIGN Multicenter retrospective observational study. SETTING Metabolic centers. PATIENT(S) Adult women (aged >18 y) with confirmed classic galactosemia and primary ovarian insufficiency were included. INTERVENTION(S) Participants and medical records were consulted to obtain study data in a standardized manner with the use of a questionnaire. MAIN OUTCOME MEASURE(S) Conception opportunities, time to pregnancy, pregnancy outcome, hormone replacement therapy use, fertility counseling, and the participants' vision of fertility were evaluated. Potential predictive factors for increased pregnancy chance were explored. RESULT(S) Eighty-five women with classic galactosemia and primary ovarian insufficiency participated. Twenty-one women actively attempted to conceive or did not take adequate contraceptive precautions. Of these 21 women, nine became pregnant spontaneously (42.9%). This was higher than reported in primary ovarian insufficiency due to other causes (5%-10%). After a period of 12 months, a cumulative proportion of 27.8% of couples had conceived, which increased to 48.4% after 24 months and 61.3% after 27 months. Predictive factors could not be identified. A considerable miscarriage rate of 30% was observed (6 of 20 pregnancies). Although a substantial proportion of women expressed a child-wish (n = 28/53; 52.8%), the vast majority of participants (n = 43/57; 75.4%) considered conceiving to be highly unlikely, owing to negative counseling in the past. CONCLUSION(S) The pregnancy rate in women with classic galactosemia and primary ovarian insufficiency was higher than for women with primary ovarian insufficiency of any cause. This shifting paradigm carries significant implications for fertility counseling and potential application of fertility preservation techniques.
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Affiliation(s)
- Britt van Erven
- Department of Pediatrics and Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Gerard T Berry
- Division of Genetics and Genomics, Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - David Cassiman
- Department of Gastroenterology-Hepatology, Metabolic Center, University Hospitals Leuven, Leuven, Belgium
| | - Geraldine Connolly
- Rotunda Hospital and Temple Street Children's University Hospital, Dublin, Ireland
| | - Maria Forga
- Endocrinology and Nutrition Department, Hospital Clinic, Barcelona, Spain
| | - Matthias Gautschi
- University Children's Hospital, Pediatric Endocrinology, Diabetes, and Metabolism, and Institute of Clinical Chemistry, Inselspital, University of Bern, Bern, Switzerland
| | - Cynthia S Gubbels
- Division of Genetics and Genomics, Boston Children's Hospital/Harvard Medical School/Broad Institute of Massachusetts Institute of Technology and Harvard, Boston, Massachusetts
| | - Carla E M Hollak
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Academic Medical Center, Amsterdam, the Netherlands
| | - Mirian C Janssen
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ina Knerr
- National Centre for Inherited Metabolic Disorders, Temple Street Children's University Hospital, Dublin, Ireland
| | - Philippe Labrune
- Hôpital Antoine Béclère, Centre de Référence Maladies Héréditaires du Métabolisme Hépatique, Hôpitaux Universitaires Paris Sud, Clamart, France
| | - Janneke G Langendonk
- Center for Lysosomal and Metabolic Diseases, Department of Internal Medicine, Erasmus MC, Rotterdam, the Netherlands
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, and Department of Pediatrics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Abel Thijs
- Department of Internal Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Rein Vos
- Department of Methodology and Statistics, School for Public Health and Primary Care, Maastricht University, Maastricht, the Netherlands
| | - Saskia B Wortmann
- Children's Hospital, Salzburger Landeskliniken and Paracelsus Medical University, Salzburg, Austria
| | - M Estela Rubio-Gozalbo
- Department of Pediatrics and Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands.
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Coelho AI, Rubio-Gozalbo ME, Vicente JB, Rivera I. Sweet and sour: an update on classic galactosemia. J Inherit Metab Dis 2017; 40:325-342. [PMID: 28281081 PMCID: PMC5391384 DOI: 10.1007/s10545-017-0029-3] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 02/14/2017] [Accepted: 02/20/2017] [Indexed: 02/03/2023]
Abstract
Classic galactosemia is a rare inherited disorder of galactose metabolism caused by deficient activity of galactose-1-phosphate uridylyltransferase (GALT), the second enzyme of the Leloir pathway. It presents in the newborn period as a life-threatening disease, whose clinical picture can be resolved by a galactose-restricted diet. The dietary treatment proves, however, insufficient in preventing severe long-term complications, such as cognitive, social and reproductive impairments. Classic galactosemia represents a heavy burden on patients' and their families' lives. After its first description in 1908 and despite intense research in the past century, the exact pathogenic mechanisms underlying galactosemia are still not fully understood. Recently, new important insights on molecular and cellular aspects of galactosemia have been gained, and should open new avenues for the development of novel therapeutic strategies. Moreover, an international galactosemia network has been established, which shall act as a platform for expertise and research in galactosemia. Herein are reviewed some of the latest developments in clinical practice and research findings on classic galactosemia, an enigmatic disorder with many unanswered questions warranting dedicated research.
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Affiliation(s)
- Ana I Coelho
- Department of Pediatrics and Department of Clinical Genetics, Maastricht University Medical Centre, P. Debyelaan 25, PO Box 5800, 6202 AZ, Maastricht, The Netherlands.
| | - M Estela Rubio-Gozalbo
- Department of Pediatrics and Department of Clinical Genetics, Maastricht University Medical Centre, P. Debyelaan 25, PO Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - João B Vicente
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Isabel Rivera
- Metabolism & Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
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Galactose and its Metabolites Deteriorate Metaphase II Mouse Oocyte Quality and Subsequent Embryo Development by Disrupting the Spindle Structure. Sci Rep 2017; 7:231. [PMID: 28331195 PMCID: PMC5427935 DOI: 10.1038/s41598-017-00159-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 02/13/2017] [Indexed: 11/23/2022] Open
Abstract
Premature ovarian insufficiency (POI) is a frequent long-term complication of classic galactosemia. The majority of women with this disorder develop POI, however rare spontaneous pregnancies have been reported. Here, we evaluate the effect of D-galactose and its metabolites, galactitol and galactose 1-phosphate, on oocyte quality as well as embryo development to elucidate the mechanism through which these compounds mediate oocyte deterioration. Metaphase II mouse oocytes (n = 240), with and without cumulus cells (CCs), were exposed for 4 hours to D-galactose (2 μM), galactitol (11 μM) and galactose 1-phosphate (0.1 mM), (corresponding to plasma concentrations in patients on galactose-restricted diet) and compared to controls. The treated oocytes showed decreased quality as a function of significant enhancement in production of reactive oxygen species (ROS) when compared to controls. The presence of CCs offered no protection, as elevated ROS was accompanied by increased apoptosis of CCs. Our results suggested that D-galactose and its metabolites disturbed the spindle structure and chromosomal alignment, which was associated with significant decline in oocyte cleavage and blastocyst development after in-vitro fertilization. The results provide insight into prevention and treatment strategies that may be used to extend the window of fertility in these patients.
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Machado CM, De-Souza EA, De-Queiroz ALFV, Pimentel FSA, Silva GFS, Gomes FM, Montero-Lomelí M, Masuda CA. The galactose-induced decrease in phosphate levels leads to toxicity in yeast models of galactosemia. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1403-1409. [PMID: 28213126 DOI: 10.1016/j.bbadis.2017.02.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/05/2017] [Accepted: 02/13/2017] [Indexed: 10/20/2022]
Abstract
Classic galactosemia is an inborn error of metabolism caused by deleterious mutations in the GALT gene. A number of evidences indicate that the galactose-1-phosphate accumulation observed in patient cells is a cause of toxicity in this disease. Nevertheless, the consequent molecular events caused by the galactose-1-phosphate accumulation remain elusive. Here we show that intracellular inorganic phosphate levels decreased when yeast models of classic galactosemia were exposed to galactose. The decrease in phosphate levels is probably due to the trapping of phosphate in the accumulated galactose-1-phosphate since the deletion of the galactokinase encoding gene GAL1 suppressed this phenotype. Galactose-induced phosphate depletion caused an increase in glycogen content, an expected result since glycogen breakdown by the enzyme glycogen phosphorylase is dependent on inorganic phosphate. Accordingly, an increase in intracellular phosphate levels suppressed the galactose effect on glycogen content and conferred galactose tolerance to yeast models of galactosemia. These results support the hypothesis that the galactose-induced decrease in phosphate levels leads to toxicity in galactosemia and opens new possibilities for the development of better treatments for this disease.
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Affiliation(s)
- Caio M Machado
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Evandro A De-Souza
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Ana Luiza F V De-Queiroz
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Felipe S A Pimentel
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Guilherme F S Silva
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Fabio M Gomes
- Laboratório de Entomologia Médica, Programa de Biologia Celular e Parasitologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
| | - Mónica Montero-Lomelí
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Claudio A Masuda
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil.
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Chen W, Caston R, Balakrishnan B, Siddiqi A, Parmar K, Tang M, Feng M, Lai K. Assessment of ataxia phenotype in a new mouse model of galactose-1 phosphate uridylyltransferase (GALT) deficiency. J Inherit Metab Dis 2017; 40:131-137. [PMID: 27783170 PMCID: PMC5203948 DOI: 10.1007/s10545-016-9993-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/10/2016] [Accepted: 10/11/2016] [Indexed: 12/14/2022]
Abstract
Despite adequate dietary management, patients with classic galactosemia continue to have increased risks of cognitive deficits, speech dyspraxia, primary ovarian insufficiency, and abnormal motor development. A recent evaluation of a new galactose-1 phosphate uridylyltransferase (GALT)-deficient mouse model revealed reduced fertility and growth restriction. These phenotypes resemble those seen in human patients. In this study, we further assess the fidelity of this new mouse model by examining the animals for the manifestation of a common neurological sequela in human patients: cerebellar ataxia. The balance, grip strength, and motor coordination of GALT-deficient and wild-type mice were tested using a modified rotarod. The results were compared to composite phenotype scoring tests, typically used to evaluate neurological and motor impairment. The data demonstrated abnormalities with varying severity in the GALT-deficient mice. Mice of different ages were used to reveal the progressive nature of motor impairment. The varying severity and age-dependent impairments seen in the animal model agree with reports on human patients. Finally, measurements of the cerebellar granular and molecular layers suggested that mutant mice experience cerebellar hypoplasia, which could have resulted from the down-regulation of the PI3K/Akt signaling pathway.
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Affiliation(s)
- Wyman Chen
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA
| | - Rose Caston
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA
- Dartmouth College, Hanover, NH, USA
| | - Bijina Balakrishnan
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA
| | - Anwer Siddiqi
- Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, Jacksonville, FL, USA
| | - Kamalpreet Parmar
- Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, Jacksonville, FL, USA
| | - Manshu Tang
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA
| | - Merry Feng
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA
| | - Kent Lai
- Department of Pediatrics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84108, USA.
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Castro MB, Ferreira BK, Cararo JH, Chipindo AE, Magenis ML, Michels M, Danielski LG, de Oliveira MR, Ferreira GC, Streck EL, Petronilho F, Schuck PF. Evidence of oxidative stress in brain and liver of young rats submitted to experimental galactosemia. Metab Brain Dis 2016; 31:1381-1390. [PMID: 27389247 DOI: 10.1007/s11011-016-9865-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/28/2016] [Indexed: 10/21/2022]
Abstract
Galactosemia is a disorder of galactose metabolism, leading to the accumulation of this carbohydrate. Galactosemic patients present brain and liver damage. For evaluated oxidative stress, 30-day-old males Wistar rats were divided into two groups: galactose group, that received a single injection of this carbohydrate (5 μmol/g), and control group, that received saline 0.9 % in the same conditions. One, twelve or twenty-four hours after the administration, animals were euthanized and cerebral cortex, cerebellum, and liver were isolated. After one hour, it was found a significant increase in TBA-RS levels, nitrate and nitrite and protein carbonyl contents in cerebral cortex, as well as protein carbonyl content in the cerebellum and in hepatic level of TBA-RS, and a significant decrease in nitrate and nitrite contents in cerebellum. TBA-RS levels were also found increased in all studied tissues, as well as nitrate and nitrite contents in cerebral cortex and cerebellum, that also present increased protein carbonyl content and impairments in the activity of antioxidant enzymes of rats euthanized at twelve hours. Finally, animals euthanized after twenty-four hours present an increase of TBA-RS levels in studied tissues, as well as the protein carbonyl content in cerebellum and liver. These animals also present an increased nitrate and nitrite content and impairment of antioxidant enzymes activities. Taken together, our data suggest that acute galactose administration impairs redox homeostasis in brain and liver of rats.
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Affiliation(s)
- Márcia B Castro
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil
- Universidade Regional Integrada do Alto Uruguai e das Missões, Erechim, RS, Brazil
| | - Bruna K Ferreira
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil
| | - José Henrique Cararo
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil
| | - Adália E Chipindo
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil
| | - Marina L Magenis
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil
| | - Monique Michels
- Laboratório de Fisiopatologia Experimental, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Lucinéia G Danielski
- Laboratório de Imunopatologia Clínica e Experimental, Programa de Pós-graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil
| | - Marcos R de Oliveira
- Departamento de Química, Instituto de Ciências Exatas e da Terra, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | - Gustavo C Ferreira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Emilio L Streck
- Laboratório de Bioenergética, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Fabricia Petronilho
- Laboratório de Imunopatologia Clínica e Experimental, Programa de Pós-graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil
| | - Patrícia F Schuck
- Laboratório de Erros Inatos do Metabolismo, Programa de Pós-graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105, bloco S, sala 6, Criciúma, SC, 88806-000, Brazil.
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Timson DJ. The molecular basis of galactosemia — Past, present and future. Gene 2016; 589:133-41. [DOI: 10.1016/j.gene.2015.06.077] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/18/2015] [Accepted: 06/29/2015] [Indexed: 12/19/2022]
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Daenzer JMI, Jumbo-Lucioni PP, Hopson ML, Garza KR, Ryan EL, Fridovich-Keil JL. Acute and long-term outcomes in a Drosophila melanogaster model of classic galactosemia occur independently of galactose-1-phosphate accumulation. Dis Model Mech 2016; 9:1375-1382. [PMID: 27562100 PMCID: PMC5117221 DOI: 10.1242/dmm.022988] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 08/17/2016] [Indexed: 01/08/2023] Open
Abstract
Classic galactosemia (CG) is a potentially lethal inborn error of metabolism that results from the profound loss of galactose-1-phosphate uridylyltransferase (GALT), the second enzyme in the Leloir pathway of galactose metabolism. Neonatal detection and dietary restriction of galactose minimizes or resolves the acute sequelae of CG, but fails to prevent the long-term complications experienced by a majority of patients. One of the substrates of GALT, galactose-1-phosphate (Gal-1P), accumulates to high levels in affected infants, especially following milk exposure, and has been proposed as the key mediator of acute and long-term pathophysiology in CG. However, studies of treated patients demonstrate no association between red blood cell Gal-1P level and long-term outcome severity. Here, we used genetic, epigenetic and environmental manipulations of a Drosophila melanogaster model of CG to test the role of Gal-1P as a candidate mediator of outcome in GALT deficiency. Specifically, we both deleted and knocked down the gene encoding galactokinase (GALK) in control and GALT-null Drosophila, and assessed the acute and long-term outcomes of the resulting animals in the presence and absence of dietary galactose. GALK is the first enzyme in the Leloir pathway of galactose metabolism and is responsible for generating Gal-1P in humans and Drosophila. Our data confirmed that, as expected, loss of GALK lowered or eliminated Gal-1P accumulation in GALT-null animals. However, we saw no concomitant rescue of larval survival or adult climbing or fecundity phenotypes. Instead, we saw that loss of GALK itself was not benign and in some cases phenocopied or exacerbated the outcome seen in GALT-null animals. These findings strongly contradict the long-standing hypothesis that Gal-1P alone underlies pathophysiology of acute and long-term outcomes in GALT-null Drosophila and suggests that other metabolite(s) of galactose, and/or other pathogenic factors, might be involved. Summary: In a GALT-deficient Drosophila model of classic galactosemia, Gal-1P accumulation is not required for compromised larval survival following galactose exposure or adult movement and fecundity phenotypes.
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Affiliation(s)
- Jennifer M I Daenzer
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | - Marquise L Hopson
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Kerry R Garza
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Emily L Ryan
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
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Balakrishnan B, Chen W, Tang M, Huang X, Cakici DD, Siddiqi A, Berry G, Lai K. Galactose-1 phosphate uridylyltransferase (GalT) gene: A novel positive regulator of the PI3K/Akt signaling pathway in mouse fibroblasts. Biochem Biophys Res Commun 2016; 470:205-212. [PMID: 26773505 DOI: 10.1016/j.bbrc.2016.01.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 01/06/2016] [Indexed: 12/19/2022]
Abstract
The vital importance of the Leloir pathway of galactose metabolism has been repeatedly demonstrated by various uni-/multicellular model organisms, as well human patients who have inherited deficiencies of the key GAL enzymes. Yet, other than the obvious links to the glycolytic pathway and glycan biosynthetic pathways, little is known about how this metabolic pathway interacts with the rest of the metabolic and signaling networks. In this study, we compared the growth and the expression levels of the key components of the PI3K/Akt growth signaling pathway in primary fibroblasts derived from normal and galactose-1 phosphate uridylyltransferase (GalT)-deficient mice, the latter exhibited a subfertility phenotype in adult females and growth restriction in both sexes. The growth potential and the protein levels of the pAkt(Thr308), pAkt(Ser473), pan-Akt, pPdk1, and Hsp90 proteins were significantly reduced by 62.5%, 60.3%, 66%, 66%, and 50%, respectively in the GalT-deficient cells. Reduced expression of phosphorylated Akt proteins in the mutant cells led to diminished phosphorylation of Gsk-3β (-74%). Protein expression of BiP and pPten were 276% and 176% higher respectively in cells with GalT-deficiency. Of the 24 genes interrogated using QIAGEN RT(2) Profiler PCR Custom Arrays, the mRNA abundance of Akt1, Pdpk1, Hsp90aa1 and Pi3kca genes were significantly reduced at least 2.03-, 1.37-, 2.45-, and 1.78-fold respectively in mutant fibroblasts. Both serum-fasted normal and GalT-deficient cells responded to Igf-1-induced activation of Akt phosphorylation at +15 min, but the mutant cells have lower phosphorylation levels. The steady-state protein abundance of Igf-1 receptor was also significantly reduced in mutant cells. Our results thus demonstrated that GalT deficiency can effect down-regulation of the PI3K/Akt growth signaling pathway in mouse fibroblasts through distinct mechanisms targeting both gene and protein expression levels.
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Affiliation(s)
- Bijina Balakrishnan
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, USA
| | - Wyman Chen
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, USA
| | - Manshu Tang
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, USA
| | - Xiaoping Huang
- Division of Genetics and Genomics, Department of Pediatrics, Harvard Medical School, USA
| | - Didem Demirbas Cakici
- Division of Genetics and Genomics, Department of Pediatrics, Harvard Medical School, USA
| | - Anwer Siddiqi
- Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, USA
| | - Gerard Berry
- Division of Genetics and Genomics, Department of Pediatrics, Harvard Medical School, USA
| | - Kent Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, USA.
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Jumbo-Lucioni P, Parkinson W, Broadie K. Overelaborated synaptic architecture and reduced synaptomatrix glycosylation in a Drosophila classic galactosemia disease model. Dis Model Mech 2014; 7:1365-78. [PMID: 25326312 PMCID: PMC4257005 DOI: 10.1242/dmm.017137] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Classic galactosemia (CG) is an autosomal recessive disorder resulting from loss of galactose-1-phosphate uridyltransferase (GALT), which catalyzes conversion of galactose-1-phosphate and uridine diphosphate (UDP)-glucose to glucose-1-phosphate and UDP-galactose, immediately upstream of UDP-N-acetylgalactosamine and UDP-N-acetylglucosamine synthesis. These four UDP-sugars are essential donors for driving the synthesis of glycoproteins and glycolipids, which heavily decorate cell surfaces and extracellular spaces. In addition to acute, potentially lethal neonatal symptoms, maturing individuals with CG develop striking neurodevelopmental, motor and cognitive impairments. Previous studies suggest that neurological symptoms are associated with glycosylation defects, with CG recently being described as a congenital disorder of glycosylation (CDG), showing defects in both N- and O-linked glycans. Here, we characterize behavioral traits, synaptic development and glycosylated synaptomatrix formation in a GALT-deficient Drosophila disease model. Loss of Drosophila GALT (dGALT) greatly impairs coordinated movement and results in structural overelaboration and architectural abnormalities at the neuromuscular junction (NMJ). Dietary galactose and mutation of galactokinase (dGALK) or UDP-glucose dehydrogenase (sugarless) genes are identified, respectively, as critical environmental and genetic modifiers of behavioral and cellular defects. Assaying the NMJ extracellular synaptomatrix with a broad panel of lectin probes reveals profound alterations in dGALT mutants, including depletion of galactosyl, N-acetylgalactosamine and fucosylated horseradish peroxidase (HRP) moieties, which are differentially corrected by dGALK co-removal and sugarless overexpression. Synaptogenesis relies on trans-synaptic signals modulated by this synaptomatrix carbohydrate environment, and dGALT-null NMJs display striking changes in heparan sulfate proteoglycan (HSPG) co-receptor and Wnt ligand levels, which are also corrected by dGALK co-removal and sugarless overexpression. These results reveal synaptomatrix glycosylation losses, altered trans-synaptic signaling pathway components, defective synaptogenesis and impaired coordinated movement in a CG neurological disease model.
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Affiliation(s)
- Patricia Jumbo-Lucioni
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37232, USA
| | - William Parkinson
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37232, USA
| | - Kendal Broadie
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37232, USA.
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Abstract
Classic galactosemia is an inherited metabolic disease for which, at present, no therapy is available apart from galactose-restricted diet. However, the efficacy of the diet is questionable, since it is not able to prevent the insurgence of chronic complications later in life. In addition, it is possible that dietary restriction itself could induce negative side effects. Therefore, there is a need for an alternative therapeutic approach that can avert the manifestation of chronic complications in the patients. In this review, the authors describe the development of a novel class of pharmaceutical agents that target the production of a toxic metabolite, galactose-1-phosphate, considered as the main culprit for the cause of the complications, in the patients.
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