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Luke RA, Cawley NX, Rahhal S, Selvaraman A, Thurm A, Wassif CA, Porter FD. Elevated cerebrospinal fluid glial fibrillary acidic protein levels in Smith-Lemli-Opitz syndrome. Mol Genet Metab 2024; 143:108570. [PMID: 39244853 PMCID: PMC11473222 DOI: 10.1016/j.ymgme.2024.108570] [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: 07/02/2024] [Revised: 08/28/2024] [Accepted: 08/28/2024] [Indexed: 09/10/2024]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a rare, multiple malformation/intellectual disability disorder caused by pathogenic variants of DHCR7. DHCR7 catalyzes the reduction of 7-dehydrocholesterol (7DHC) to cholesterol in the final step of cholesterol biosynthesis. This results in accumulation of 7DHC and a cholesterol deficiency. Although the biochemical defect is well delineated and multiple mechanisms underlying developmental defects have been explored, the post developmental neuropathological consequences of altered central nervous system sterol composition have not been studied. Preclinical studies suggest that astroglial activation may occur in SLOS. To determine if astroglial activation is present in individuals with SLOS, we quantified cerebrospinal fluid (CSF) glial fibrillary acidic protein using a Quanterix Simoa® GFAP Discovery Kit for SR-X™. Relative to an age-appropriate comparison group, we found that CSF GFAP levels were elevated 3.9-fold in SLOS (3980 ± 3732 versus 1010 ± 577 pg/ml, p = 0.0184). Simvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor, has previously been shown to increase expression of hypomorphic DHCR7 alleles and in a placebo-controlled trial improved serum sterol levels and decreased irritability. Using archived CSF samples from that prior study, we observed a significant decrease (p = 0.0119) in CSF GFAP levels in response to treatment with simvastatin. Although further work needs to be done to understand the potential contribution of neuroinflammation to SLOS neuropathology and cognitive dysfunction, these data confirm astroglial activation in SLOS and suggest that CSF GFAP may be a useful biomarker to monitor therapeutic responses.
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Affiliation(s)
- Rachel A Luke
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Niamh X Cawley
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Samar Rahhal
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Aishwarya Selvaraman
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Audrey Thurm
- Neurodevelopmental and Behavioral Phenotyping Service, National Institute of Mental Health, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Christopher A Wassif
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Forbes D Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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2
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Yılmaz M, Bebek O, Turkyilmaz A. Smith-Lemli-Opitz Syndrome with Biallelic c.1295A>G (p.Tyr432Cys) Variant in the DHCR7 Gene in a 73-Year-Old Woman: Report of the Oldest Patient. Mol Syndromol 2024; 15:317-323. [PMID: 39119449 PMCID: PMC11305663 DOI: 10.1159/000536343] [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: 12/17/2023] [Accepted: 01/16/2024] [Indexed: 08/10/2024] Open
Abstract
Introduction Smith-Lemli-Opitz syndrome (SLOS), a genetic developmental disorder characterized by various congenital anomalies, arises from a loss of normal DHCR7 enzymatic action in cholesterol biosynthesis. This syndrome is typically marked by various congenital anomalies, including microcephaly with cognitive impairments, distinctive facial features, and syndactyly of the toes (2-3 fusion). Case Presentation A 73-year-old woman, followed up on by the neurology clinic for the last 3 years for amnesia and movement disorders, was referred to our clinic for genetic etiology investigation. Although there were no significant dysmorphic findings on her physical examination, observations included partial syndactyly between the second and third toes of both feet, a wide forehead, and a triangular face. We used the whole-exome sequencing (WES) analysis to evaluate the patient because of their various phenotype, which included dysmorphic features, movement problems, recurrent hip dislocation, mild intellectual impairment. WES analysis revealed a homozygous missense c.1295A>G (p.Tyr432Cys) variation in DHCR7 gene. Discussion A total of 9 patients with p.Tyr432Cys variant have been reported in the literature so far. The present case is the first patient with biallelic c.1295A>G (p.Tyr432Cys) variation in DHCR7 gene in the current literature. Diagnosing the disorder can be challenging, particularly in its milder manifestations, given the extensive range of clinical presentations. The present case is the oldest patient with SLOS reported in the relevant literature. Mild dysmorphic features, mild intellectual disability, and recurrent hip dislocation, along with the typical finding of syndactyly between the second and third toes in the foot, may indicate mild forms of SLOS.
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Affiliation(s)
- Mustafa Yılmaz
- Department of Medical Genetics, Karadeniz Technical University Faculty of Medicine, Trabzon, Turkey
| | - Ogun Bebek
- Karadeniz Technical University Faculty of Medicine, Trabzon, Turkey
| | - Ayberk Turkyilmaz
- Department of Medical Genetics, Karadeniz Technical University Faculty of Medicine, Trabzon, Turkey
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3
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Li A, Tomita H, Xu L. Temporal gene expression changes and affected pathways in neurodevelopment of a mouse model of Smith-Lemli-Opitz syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.21.568116. [PMID: 38045361 PMCID: PMC10690207 DOI: 10.1101/2023.11.21.568116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Smith-Lemli-Opitz syndrome is an autosomal recessive disorder that arises from mutations in the gene DHCR7, which encodes the terminal enzyme of cholesterol biosynthesis, leading to decreased production of cholesterol and accumulation of the cholesterol precursor, 7-dehydrocholesterol, and its oxysterol metabolites. The disorder displays a wide range of neurodevelopmental defects, intellectual disability, and behavioral problems. However, an in-depth study on the temporal changes of gene expression in the developing brains of SLOS mice has not been done before. In this work, we carried out the transcriptomic analysis of whole brains from WT and Dhcr7-KO mice at four-time points through postnatal day 0. First, we observed the expected downregulation of the Dhcr7 gene in the Dhcr7-KO mouse model, as well as gene expression changes of several other genes involved in cholesterol biosynthesis throughout all time points. Pathway and GO term enrichment analyses revealed affected signaling pathways and biological processes that were shared amongst time points and unique to individual time points. Specifically, the pathways important for embryonic development, including Hippo, Wnt, and TGF-β signaling pathways are the most significantly affected at the earliest time point, E12.5. Additionally, neurogenesis-related GO terms were enriched in earlier time points, consistent with the timing of development. Conversely, pathways related to synaptogenesis, which occurs later in development compared to neurogenesis, are significantly affected at the later time points, E16.5 and PND0, including the cholinergic, glutamatergic, and GABAergic synapses. The impact of these transcriptomic changes and enriched pathways is discussed in the context of known biological phenotypes of SLOS.
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Affiliation(s)
- Amy Li
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Hideaki Tomita
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Libin Xu
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
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4
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Li A, Xu L. MALDI-IM-MS Imaging of Brain Sterols and Lipids in a Mouse Model of Smith-Lemli-Opitz Syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.02.560415. [PMID: 37873113 PMCID: PMC10592934 DOI: 10.1101/2023.10.02.560415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a neurodevelopmental disorder caused by genetic mutations in the DHCR7 gene, encoding the enzyme 3β-hydroxysterol-Δ7-reductase (DHCR7) that catalyzes the last step of cholesterol synthesis. The resulting deficiency in cholesterol and accumulation of its precursor, 7-dehydrocholesterol (7-DHC), have a profound impact on brain development, which manifests as developmental delay, cognitive impairment, and behavioral deficits. To understand how the brain regions are differentially affected by the defective Dhcr7, we aim to map the regional distribution of sterols and other lipids in neonatal brains from a Dhcr7-KO mouse model of SLOS, using mass spectrometry imaging (MSI). MSI enables spatial localization of biomolecules in situ on the surface of a tissue section, which is particularly useful for mapping the changes that occur within a metabolic disorder such as SLOS, and in an anatomically complex organ such as the brain. In this work, using MALDI-ion mobility (IM)-MSI, we successfully determined the regional distribution of features that correspond to cholesterol, 7-DHC/desmosterol, and the precursor of desmosterol, 7-dehydrodesmosterol, in WT and Dhcr7-KO mice. Interestingly, we also observed m/z values that match the major oxysterol metabolites of 7-DHC (DHCEO and hydroxy-7-DHC), which displayed similar patterns as 7-DHC. We then identified brain lipids using m/z and CCS at the Lipid Species-level and curated a database of MALDIIM-MS-derived lipid CCS values. Subsequent statistical analysis of regions-of-interest allowed us to identify differentially expressed lipids between Dhcr7-KO and WT brains, which could contribute to defects in myelination, neurogenesis, neuroinflammation, and learning and memory in SLOS.
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Affiliation(s)
- Amy Li
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Libin Xu
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
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5
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Barnes-Vélez JA, Aksoy Yasar FB, Hu J. Myelin lipid metabolism and its role in myelination and myelin maintenance. Innovation (N Y) 2023; 4:100360. [PMID: 36588745 PMCID: PMC9800635 DOI: 10.1016/j.xinn.2022.100360] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Myelin is a specialized cell membrane indispensable for rapid nerve conduction. The high abundance of membrane lipids is one of myelin's salient features that contribute to its unique role as an insulator that electrically isolates nerve fibers across their myelinated surface. The most abundant lipids in myelin include cholesterol, glycosphingolipids, and plasmalogens, each playing critical roles in myelin development as well as function. This review serves to summarize the role of lipid metabolism in myelination and myelin maintenance, as well as the molecular determinants of myelin lipid homeostasis, with an emphasis on findings from genetic models. In addition, the implications of myelin lipid dysmetabolism in human diseases are highlighted in the context of hereditary leukodystrophies and neuropathies as well as acquired disorders such as Alzheimer's disease.
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Affiliation(s)
- Joseph A. Barnes-Vélez
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
- University of Puerto Rico Medical Sciences Campus, School of Medicine, San Juan, PR 00936-5067, USA
| | - Fatma Betul Aksoy Yasar
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
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6
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Freel BA, Kelvington BA, Sengupta S, Mukherjee M, Francis KR. Sterol dysregulation in Smith-Lemli-Opitz syndrome causes astrocyte immune reactivity through microglia crosstalk. Dis Model Mech 2022; 15:dmm049843. [PMID: 36524414 PMCID: PMC10655813 DOI: 10.1242/dmm.049843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/17/2022] [Indexed: 12/23/2022] Open
Abstract
Owing to the need for de novo cholesterol synthesis and cholesterol-enriched structures within the nervous system, cholesterol homeostasis is critical to neurodevelopment. Diseases caused by genetic disruption of cholesterol biosynthesis, such as Smith-Lemli-Opitz syndrome, which is caused by mutations in 7-dehydrocholesterol reductase (DHCR7), frequently result in broad neurological deficits. Although astrocytes regulate multiple neural processes ranging from cell migration to network-level communication, immunological activation of astrocytes is a hallmark pathology in many diseases. However, the impact of DHCR7 on astrocyte function and immune activation remains unknown. We demonstrate that astrocytes from Dhcr7 mutant mice display hallmark signs of reactivity, including increased expression of glial fibrillary acidic protein (GFAP) and cellular hypertrophy. Transcript analyses demonstrate extensive Dhcr7 astrocyte immune activation, hyper-responsiveness to glutamate stimulation and altered calcium flux. We further determine that the impacts of Dhcr7 are not astrocyte intrinsic but result from non-cell-autonomous effects of microglia. Our data suggest that astrocyte-microglia crosstalk likely contributes to the neurological phenotypes observed in disorders of cholesterol biosynthesis. Additionally, these data further elucidate a role for cholesterol metabolism within the astrocyte-microglia immune axis, with possible implications in other neurological diseases.
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Affiliation(s)
- Bethany A. Freel
- Basic Biomedical Sciences, University of South Dakota, Vermillion, SD 57069, USA
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Benjamin A. Kelvington
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Sonali Sengupta
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Malini Mukherjee
- Functional Genomics and Bioinformatics Core, Sanford Research, Sioux Falls, SD 57104, USA
| | - Kevin R. Francis
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD 57104, USA
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD 57105, USA
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7
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Korade Z, Heffer M, Mirnics K. Medication effects on developmental sterol biosynthesis. Mol Psychiatry 2022; 27:490-501. [PMID: 33820938 PMCID: PMC8490477 DOI: 10.1038/s41380-021-01074-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/01/2021] [Accepted: 03/19/2021] [Indexed: 02/01/2023]
Abstract
Cholesterol is essential for normal brain function and development. Genetic disruptions of sterol biosynthesis result in intellectual and developmental disabilities. Developing neurons synthesize their own cholesterol, and disruption of this process can occur by both genetic and chemical mechanisms. Many commonly prescribed medications interfere with sterol biosynthesis, including haloperidol, aripiprazole, cariprazine, fluoxetine, trazodone and amiodarone. When used during pregnancy, these compounds might have detrimental effects on the developing brain of the offspring. In particular, inhibition of dehydrocholesterol-reductase 7 (DHCR7), the last enzyme in the biosynthesis pathway, results in accumulation of the immediate cholesterol precursor, 7-dehydrocholesterol (7-DHC). 7-DHC is highly unstable, giving rise to toxic oxysterols; this is particularly pronounced in a mouse model when both the mother and the offspring carry the Dhcr7+/- genotype. Studies of human dermal fibroblasts from individuals who carry DCHR7+/- single allele mutations suggest that the same gene*medication interaction also occurs in humans. The public health relevance of these findings is high, as DHCR7-inhibitors can be considered teratogens, and are commonly used by pregnant women. In addition, sterol biosynthesis inhibiting medications should be used with caution in individuals with mutations in sterol biosynthesis genes. In an age of precision medicine, further research in this area could open opportunities to improve patient and fetal/infant safety by tailoring medication prescriptions according to patient genotype and life stage.
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Affiliation(s)
- Zeljka Korade
- Department of Pediatrics, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA, 68198.,Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA, 68198
| | - Marija Heffer
- J. J. Strossmayer University of Osijek, Faculty of Medicine Osijek, Department of Medical Biology and Genetics, Josipa Huttlera 4, 31000 Osijek, Croatia
| | - Károly Mirnics
- Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA. .,Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE, 68105, USA.
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8
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den Hollander B, Rasing A, Post MA, Klein WM, Oud MM, Brands MM, de Boer L, Engelke UFH, van Essen P, Fuchs SA, Haaxma CA, Jensson BO, Kluijtmans LAJ, Lengyel A, Lichtenbelt KD, Østergaard E, Peters G, Salvarinova R, Simon MEH, Stefansson K, Thorarensen Ó, Ulmen U, Coene KLM, Willemsen MA, Lefeber DJ, van Karnebeek CDM. NANS-CDG: Delineation of the Genetic, Biochemical, and Clinical Spectrum. Front Neurol 2021; 12:668640. [PMID: 34163424 PMCID: PMC8215539 DOI: 10.3389/fneur.2021.668640] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/09/2021] [Indexed: 12/18/2022] Open
Abstract
Background: NANS-CDG is a recently described congenital disorder of glycosylation caused by biallelic genetic variants in NANS, encoding an essential enzyme in de novo sialic acid synthesis. Sialic acid at the end of glycoconjugates plays a key role in biological processes such as brain and skeletal development. Here, we present an observational cohort study to delineate the genetic, biochemical, and clinical phenotype and assess possible correlations. Methods: Medical and laboratory records were reviewed with retrospective extraction and analysis of genetic, biochemical, and clinical data (2016–2020). Results: Nine NANS-CDG patients (nine families, six countries) referred to the Radboudumc CDG Center of Expertise were included. Phenotyping confirmed the hallmark features including intellectual developmental disorder (IDD) (n = 9/9; 100%), facial dysmorphisms (n = 9/9; 100%), neurologic impairment (n = 9/9; 100%), short stature (n = 8/9; 89%), skeletal dysplasia (n = 8/9; 89%), and short limbs (n = 8/9; 89%). Newly identified features include ophthalmological abnormalities (n = 6/9; 67%), an abnormal septum pellucidum (n = 6/9; 67%), (progressive) cerebral atrophy and ventricular dilatation (n = 5/9; 56%), gastrointestinal dysfunction (n = 5/9; 56%), thrombocytopenia (n = 5/9; 56%), and hypo–low-density lipoprotein cholesterol (n = 4/9; 44%). Biochemically, elevated urinary excretion of N-acetylmannosamine (ManNAc) is pathognomonic, the concentrations of which show a significant correlation with clinical severity. Genotypically, eight novel NANS variants were identified. Three severely affected patients harbored identical compound heterozygous pathogenic variants, one of whom was initiated on experimental prenatal and postnatal treatment with oral sialic acid. This patient showed markedly better psychomotor development than the other two genotypically identical males. Conclusions: ManNAc screening should be considered in all patients with IDD, short stature with short limbs, facial dysmorphisms, neurologic impairment, and an abnormal septum pellucidum +/– congenital and neurodegenerative lesions on brain imaging, to establish a precise diagnosis and contribute to prognostication. Personalized management includes accurate genetic counseling and access to proper supports and tailored care for gastrointestinal symptoms, thrombocytopenia, and epilepsy, as well as rehabilitation services for cognitive and physical impairments. Motivated by the short-term positive effects of experimental treatment with oral sialic, we have initiated this intervention with protocolized follow-up of neurologic, systemic, and growth outcomes in four patients. Research is ongoing to unravel pathophysiology and identify novel therapeutic targets.
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Affiliation(s)
- Bibiche den Hollander
- Department of Pediatric Metabolic Diseases, Emma Children's Hospital, Amsterdam University Medical Center, Amsterdam, Netherlands.,Department of Pediatric Metabolic Diseases, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,United for Metabolic Diseases, Amsterdam, Netherlands
| | - Anne Rasing
- Department of Pediatric Metabolic Diseases, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Merel A Post
- United for Metabolic Diseases, Amsterdam, Netherlands.,Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands.,Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Willemijn M Klein
- Department of Radiology and Nuclear Medicine and Anatomy, Radboud University Medical Centre, Nijmegen, Netherlands
| | - Machteld M Oud
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Marion M Brands
- Department of Pediatric Metabolic Diseases, Emma Children's Hospital, Amsterdam University Medical Center, Amsterdam, Netherlands.,United for Metabolic Diseases, Amsterdam, Netherlands
| | - Lonneke de Boer
- Department of Pediatric Metabolic Diseases, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Udo F H Engelke
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Peter van Essen
- Radboudumc Technology Center Clinical Studies, Radboud University Medical Center, Nijmegen, Netherlands
| | - Sabine A Fuchs
- United for Metabolic Diseases, Amsterdam, Netherlands.,Department of Pediatric Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, Netherlands
| | - Charlotte A Haaxma
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | | | - Leo A J Kluijtmans
- United for Metabolic Diseases, Amsterdam, Netherlands.,Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Anna Lengyel
- 2nd Department of Pediatrics, Semmelweis University, Budapest, Hungary
| | | | - Elsebet Østergaard
- Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gera Peters
- Department of Rehabilitation Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Ramona Salvarinova
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.,BC Children's Hospital Research Institute, The University of British Columbia, Vancouver, BC, Canada
| | - Marleen E H Simon
- Department of Genetics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Kari Stefansson
- Decode Genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland
| | - Ólafur Thorarensen
- Department of Pediatrics, Children's Medical Center, Landspitali-The National University Hospital of Iceland, Reykjavík, Iceland
| | - Ulrike Ulmen
- Department of Pediatrics, Sana Klinikum Lichtenberg, Berlin, Germany
| | - Karlien L M Coene
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Michèl A Willemsen
- United for Metabolic Diseases, Amsterdam, Netherlands.,Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Dirk J Lefeber
- United for Metabolic Diseases, Amsterdam, Netherlands.,Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands.,Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Clara D M van Karnebeek
- Department of Pediatric Metabolic Diseases, Emma Children's Hospital, Amsterdam University Medical Center, Amsterdam, Netherlands.,Department of Pediatric Metabolic Diseases, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,United for Metabolic Diseases, Amsterdam, Netherlands.,Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.,BC Children's Hospital Research Institute, The University of British Columbia, Vancouver, BC, Canada
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9
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Gana S, Plumari M, Rossi E, Saracino A, Iorio M, Zanaboni MP, Orcesi S, Valente EM. Alazami syndrome: Phenotypic expansion and clinical resemblance to Smith-Lemli-Opitz syndrome. Am J Med Genet A 2020; 182:2722-2726. [PMID: 32888391 DOI: 10.1002/ajmg.a.61832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/20/2020] [Accepted: 07/28/2020] [Indexed: 11/07/2022]
Abstract
Biallelic mutations in the LARP7 gene have been recently shown to cause Alazami syndrome, a rare condition characterized by short stature, intellectual disability, and peculiar facial dysmorphisms. To date, only 24 cases have been reported. Here, we describe two brothers initially suspected to have Smith-Lemli-Opitz syndrome, in whom clinical exome sequencing detected a novel homozygous truncating variant in LARP7. These cases expand the phenotypic spectrum of Alazami syndrome to include toes syndactyly and adaptive behavior, and confirm the power of "genotype first" approach in patients with syndromic presentations overlapping distinct rare conditions.
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Affiliation(s)
- Simone Gana
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Massimo Plumari
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Elena Rossi
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Annalisa Saracino
- Child Neurology and Psychiatry Unit, Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Melanie Iorio
- Child Neurology and Psychiatry Unit, Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | | | - Simona Orcesi
- Child Neurology and Psychiatry Unit, Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Enza Maria Valente
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy
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10
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BoAli AY, Alfadhel M, Tabarki B. Neurometabolic disorders and congenital malformations of the central nervous system. ACTA ACUST UNITED AC 2019; 23:97-103. [PMID: 29664449 PMCID: PMC8015440 DOI: 10.17712/nsj.2018.2.20170481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Both malformations of the central nervous system and neurometabolic disorders are common, mainly in highly consanguineous populations. Both metabolic pathways and developmental pathways are closely related and interact with each other. Neurometabolic disorders can lead to disturbances in brain development through multiple mechanisms that include deficits in energy metabolism, critical nutrient deficiency, accumulation of neurotoxic substrates, abnormality in cell membrane constituents, and interference in cell-to-cell signaling pathways. The anomalies observed include absent or hypoplastic corpus callosum, midline brain defects, and malformations of the cortex, the cerebellum and the brain stem. Early diagnosis of an underlying inherited neurometabolic disorders is critical for the institution of treatment, which may positively influence prognosis, and allow for proper genetic counseling. In this review, we discuss those disorders in which the structural brain malformation is a dominant feature, and propose a practical approach that will permit a physician to investigate, and treat these disorders.
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Affiliation(s)
- Ahmed Y BoAli
- Divisions of Pediatric Neurology, Department of Pediatrics, Prince Sultan Military Medical City,Riyadh, Kingdom of Saudi Arabia
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11
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Kruszka P, Muenke M. Syndromes associated with holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:229-237. [PMID: 29770994 DOI: 10.1002/ajmg.c.31620] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 04/11/2018] [Accepted: 04/16/2018] [Indexed: 01/29/2023]
Abstract
Holoprosencephaly (HPE) is partial or complete failure of the forebrain to divide into hemispheres and can be an isolated finding or associated with a syndrome. Most cases of HPE are associated with a syndrome and roughly 40%-60% of fetuses with HPE have trisomy 13 which is the most common etiology of HPE. Other syndromes associated with HPE include additional aneuploidies like trisomy 18 and single gene disorders such as Smith-Lemli-Opitz syndrome. There are a number of syndromes such as pseudotrisomy 13 which do not have a known molecular etiology; therefore, this review has two parts: syndromes with a molecular diagnosis and syndromes where the etiology is yet to be found. As most HPE is syndromic, this review provides a comprehensive list and description of syndromes associated with HPE that may be used as a differential diagnosis and starting point for evaluating individuals with HPE.
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Affiliation(s)
- Paul Kruszka
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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Dang Do AN, Baker EH, Warren KE, Bianconi SE, Porter FD. Spontaneously regressing brain lesions in Smith-Lemli-Opitz syndrome. Am J Med Genet A 2017; 176:386-390. [PMID: 29226552 DOI: 10.1002/ajmg.a.38563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 11/10/2022]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a metabolic disorder caused by an inborn error of cholesterol synthesis that affects the development of many organ systems. Malformations in the central nervous system typically involve midline structures and reflect abnormal growth and differentiation of neurons and supporting cells. Despite these defects in central nervous system development, brain tumor formation has only rarely been reported in association with SLOS. We present three individuals with SLOS and lesions in the basal ganglia or brainstem detected by MRI that were concerning for tumor formation. However, the individuals' clinical and neurological course remained stable, and the lesions regressed after several years. These lesions have similarities to spongiotic changes observed in individuals with neurofibromatosis type 1 (NF1). Notably, impaired activity of small GTPases is present in both SLOS and NF1, perhaps giving mechanistic insight into the formation of these lesions.
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Affiliation(s)
- An N Dang Do
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Eva H Baker
- Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland
| | - Katherine E Warren
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Simona E Bianconi
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Forbes D Porter
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
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Eroglu Y, Nguyen-Driver M, Steiner RD, Merkens L, Merkens M, Roullet JB, Elias E, Sarphare G, Porter FD, Li C, Tierney E, Nowaczyk MJ, Freeman KA. Normal IQ is possible in Smith-Lemli-Opitz syndrome. Am J Med Genet A 2017; 173:2097-2100. [PMID: 28349652 PMCID: PMC6016830 DOI: 10.1002/ajmg.a.38125] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/28/2016] [Accepted: 12/08/2016] [Indexed: 12/19/2022]
Abstract
Children with Smith-Lemli-Opitz syndrome (SLOS) are typically reported to have moderate to severe intellectual disability. This study aims to determine whether normal cognitive function is possible in this population and to describe clinical, biochemical and molecular characteristics of children with SLOS and normal intelligent quotient (IQ). The study included children with SLOS who underwent cognitive testing in four centers. All children with at least one IQ composite score above 80 were included in the study. Six girls, three boys with SLOS were found to have normal or low-normal IQ in a cohort of 145 children with SLOS. Major/multiple organ anomalies and low serum cholesterol levels were uncommon. No correlation with IQ and genotype was evident and no specific developmental profile were observed. Thus, normal or low-normal cognitive function is possible in SLOS. Further studies are needed to elucidate factors contributing to normal or low-normal cognitive function in children with SLOS.
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Affiliation(s)
- Yasemen Eroglu
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
| | - Mina Nguyen-Driver
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
- Institute on Development and Disability, Oregon Health and Science University, Portland, Oregon
| | - Robert D Steiner
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
- Institute on Development and Disability, Oregon Health and Science University, Portland, Oregon
- Department of Molecular and Medical Genetics, Institute on Development and Disability, Doernbecher Children's Hospital, Portland, Oregon
- Department of Pediatrics, University of Wisconsin, Madison, Wisconsin
| | - Louise Merkens
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
| | - Mark Merkens
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
| | - Jean-Baptiste Roullet
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
- Department of Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington
| | - Ellen Elias
- Children's Hospital Colorado, Aurora, Colorado
| | | | - Forbes D Porter
- Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institution of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Chumei Li
- Department of Pathology and Medicine, and Pediatrics, McMaster University, Hamilton, ON, Canada
| | | | - Małgorzata J Nowaczyk
- Department of Pathology and Medicine, and Pediatrics, McMaster University, Hamilton, ON, Canada
| | - Kurt A Freeman
- Department of Pediatrics, Oregon Health and Science University, Portland, Oregon
- Institute on Development and Disability, Oregon Health and Science University, Portland, Oregon
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Modulated DISP3/PTCHD2 expression influences neural stem cell fate decisions. Sci Rep 2017; 7:41597. [PMID: 28134287 PMCID: PMC5278513 DOI: 10.1038/srep41597] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 12/21/2016] [Indexed: 12/17/2022] Open
Abstract
Neural stem cells (NSCs) are defined by their dual ability to self-renew through mitotic cell division or differentiate into the varied neural cell types of the CNS. DISP3/PTCHD2 is a sterol-sensing domain-containing protein, highly expressed in neural tissues, whose expression is regulated by thyroid hormone. In the present study, we used a mouse NSC line to investigate what effect DISP3 may have on the self-renewal and/or differentiation potential of the cells. We demonstrated that NSC differentiation triggered significant reduction in DISP3 expression in the resulting astrocytes, neurons and oligodendrocytes. Moreover, when DISP3 expression was disrupted, the NSC "stemness" was suppressed, leading to a larger population of cells undergoing spontaneous neuronal differentiation. Conversely, overexpression of DISP3 resulted in increased NSC proliferation. When NSCs were cultured under differentiation conditions, we observed that the lack of DISP3 augmented the number of NSCs differentiating into each of the neural cell lineages and that neuronal morphology was altered. In contrast, DISP3 overexpression resulted in impaired cell differentiation. Taken together, our findings imply that DISP3 may help dictate the NSC cell fate to either undergo self-renewal or switch to the terminal differentiation cell program.
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Aslan A, Borcek AO, Pamukcuoglu S, Baykaner MK. Intracranial undifferentiated malign neuroglial tumor in Smith-Lemli-Opitz syndrome: A theory of a possible predisposing factor for primary brain tumors via a case report. Childs Nerv Syst 2017; 33:171-177. [PMID: 27526097 DOI: 10.1007/s00381-016-3214-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 08/03/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND Smith-Lemli-Opitz Syndrome (SLOS) is a rare hereditary autosomal recessive disorder with broken cholesterol synthesis causing by 7-dehydrocholesterol reductase deficiency. Although the clinical features and pathogenesis is well-defined, it is unknown whether there is a relationship between SLOS and neoplastic processes, especially brain neoplasms. PURPOSE We aimed to attract the attentions to any possibility of relation between SLOS and intracranial tumor development via a pediatric case with both intracranial high-grade neuroglial tumor and SLOS, and thus to contribute an additional data to the literature on togetherness of these two clinical conditions. METHOD In our clinic, we experienced an interesting case of a 10-year-old child with both SLOS and huge brain tumor as rarely seen. Here, we reviewed the features and pathophysiology of SLOS and brain tumors via this case. RESULTS The patient was operated in our clinic, after, his brain tumor had been diagnosed, and his histopathology was resulted in undifferentiated malignant neuroglial WHO grade 4 tumor. CONCLUSION According to current literature, our case is the first report on coexisting of SLOS and intracranial undifferentiated malignant neuroglial tumor. Common pathways like impaired sonic hedgehog (Shh) signaling pathway may be considered for pathogenesis of a probable link between SLOS and brain tumors in further studies.
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Affiliation(s)
- Ayfer Aslan
- Neurosurgery Department, Faculty of Medicine, Gazi University, Ankara, Turkey.
| | - Alp Ozgun Borcek
- Division of Pediatric Neurosurgery, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Selma Pamukcuoglu
- Department of Pathology, Gazi University Faculty of Medicine, Ankara, Turkey
| | - M Kemali Baykaner
- Division of Pediatric Neurosurgery, Faculty of Medicine, Gazi University, Ankara, Turkey
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Thurm A, Tierney E, Farmer C, Albert P, Joseph L, Swedo S, Bianconi S, Bukelis I, Wheeler C, Sarphare G, Lanham D, Wassif CA, Porter FD. Development, behavior, and biomarker characterization of Smith-Lemli-Opitz syndrome: an update. J Neurodev Disord 2016; 8:12. [PMID: 27053961 PMCID: PMC4822234 DOI: 10.1186/s11689-016-9145-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 03/24/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive inborn error of cholesterol metabolism syndrome with neurocognitive manifestations. SLOS is the result of mutations in the gene encoding the 7-dehydrocholesterol reductase, which results in the elevation of the cholesterol precursor 7-dehydrocholesterol (7-DHC). Previous reports indicate that intellectual disability, behavioral disturbances, and autism symptoms are frequently part of the SLOS behavioral phenotype. In the current study, we characterize the developmental history and current behavior of 33 individuals with SLOS aged 4 to 23 years and report on biomarkers 7-DHC and 8-DHC in relation to cognition and behavior. METHODS This was an observational case series, wherein participants with SLOS underwent extensive behavioral evaluation of cognitive function, adaptive function, autism symptoms, and problem behaviors, in addition to parent report of developmental milestones. Serum and CSF were contemporaneously obtained from the majority of participants. RESULTS Developmental milestones such as walking, talking, and toileting were uniformly delayed. Overall levels of cognitive and adaptive functioning were low; no participant received adaptive behavior scores in the average range, and the mean level of cognitive functioning in the full sample was in the moderate range of impairment. Aggressive behavior was present in nearly half of participants. Although the majority of participants had elevated scores on the gold standard autism diagnostic instruments, only about half of participants received a clinical diagnosis of autism spectrum disorder. Finally, while CSF cholesterol was not found to correlate with cognitive or adaptive functioning, both serum and CSF 7-DHC and 8-DHC (and their ratios with cholesterol) were moderately and negatively correlated with functioning in this group. CONCLUSIONS A history of developmental delay, followed by intellectual disability, is common in individuals with SLOS. Although autism spectrum disorder appears to be a frequent diagnosis in this population, it is apparent that the low level of functioning observed in SLOS may artificially inflate scores on standard autism assessments. Our findings further support that cholesterol precursors 7-DHC and 8-DHC are important biomarkers of the level of functioning in SLOS, especially regarding cognitive abilities, and thus may be to explore as mediators within the context of treatment trials. TRIAL REGISTRATION ClinicalTrials.gov, NCT00001721, NCT00064792.
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Affiliation(s)
- Audrey Thurm
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, MD 20892 USA
| | - Elaine Tierney
- Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205 USA ; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
| | - Cristan Farmer
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, MD 20892 USA
| | - Phebe Albert
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, MD 20892 USA
| | - Lisa Joseph
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, MD 20892 USA
| | - Susan Swedo
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, MD 20892 USA
| | - Simona Bianconi
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892 USA
| | - Irena Bukelis
- Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205 USA
| | - Courtney Wheeler
- Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205 USA
| | - Geeta Sarphare
- Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205 USA
| | - Diane Lanham
- Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205 USA
| | - Christopher A Wassif
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892 USA
| | - Forbes D Porter
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892 USA
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Modeling Smith-Lemli-Opitz syndrome with induced pluripotent stem cells reveals a causal role for Wnt/β-catenin defects in neuronal cholesterol synthesis phenotypes. Nat Med 2016; 22:388-96. [PMID: 26998835 PMCID: PMC4823163 DOI: 10.1038/nm.4067] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 02/16/2016] [Indexed: 02/08/2023]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a malformation disorder caused by mutations in DHCR7, impairing the reduction of 7-dehydrocholesterol to cholesterol. SLOS results in cognitive impairment, behavioral abnormalities, and nervous system defects, though neither cellular targets nor affected signaling pathways are defined. Whether 7-dehydrocholesterol accumulation or cholesterol loss is primarily responsible for disease pathogenesis is also unclear. Using induced pluripotent stem cells (iPSCs) from SLOS subjects, we identified cellular defects leading to precocious neuronal specification within SLOS derived neural progenitors. We also demonstrated that 7-dehydrocholesterol accumulation, not cholesterol deficiency, is critical for SLOS-associated defects. We further identified downregulation of Wnt/β-catenin signaling as a key initiator of aberrant SLOS iPSCs differentiation through the direct inhibitory effects of 7-dehydrocholesterol on the formation of an active Wnt receptor complex. Activation of canonical Wnt signaling prevented the neural phenotypes observed in SLOS iPSCs, suggesting that Wnt signaling may be a promising therapeutic target for SLOS.
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Bianconi SE, Cross JL, Wassif CA, Porter FD. Pathogenesis, Epidemiology, Diagnosis and Clinical Aspects of Smith-Lemli-Opitz Syndrome. Expert Opin Orphan Drugs 2015; 3:267-280. [PMID: 25734025 PMCID: PMC4343216 DOI: 10.1517/21678707.2015.1014472] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Smith-Lemli-Opitz Syndrome (SLOS) is a malformation syndrome inherited in an autosomal recessive fashion. It is due to a metabolic defect in the conversion of 7-dehydrocholesterol to cholesterol, which leads to an accumulation of 7-dehydrocholesterol and frequently a deficiency of cholesterol. The syndrome is characterized by typical dysmorphic facial features, multiple malformations, and intellectual disability. AREAS COVERED In this paper we provide an overview of the clinical phenotype and discuss how the manifestations of the syndrome vary depending on the age of the patients. We then explore the underlying biochemical defect and pathophysiological alterations that may contribute to the many disease manifestations. Subsequently we explore the epidemiology and succinctly discuss population genetics as they relate to SLOS. The next section presents the diagnostic possibilities. Thereafter, the treatment and management as is standard of care are presented. EXPERT OPINION Even though the knowledge of the underlying molecular mutations and the biochemical alterations is being rapidly accumulated, there is currently no efficacious therapy addressing neurological dysfunction. We discuss the difficulty of treating this disorder, which manifests as a combination of a malformation syndrome and an inborn error of metabolism. A very important factor in developing new therapies is the need to rigorously establish efficacy in controlled trials.
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Affiliation(s)
- Simona E Bianconi
- National Institute of Child Health and Human Development, Program in Developmental Endocrinology and Genetics, Section on Molecular Dysmorphology, 10 Center Drive, Bld 10 Rm 9D42, Bethesda, MD 20892,
| | - Joanna L Cross
- National Institute of Child Health and Human Development, Program in Developmental Endocrinology and Genetics, Section on Molecular Dysmorphology, 10 Center Drive, Bld 10 CRC, Rm 1-3288, Bethesda, MD 20892
| | - Christopher A Wassif
- National Institute of Child Health and Human Development, Program in Developmental Endocrinology and Genetics, Section on Molecular Dysmorphology, 10 Center Drive, Bld 10 CRC, Rm 1-3288, Bethesda, MD 20892
| | - Forbes D Porter
- National Institute of Child Health and Human Development, Program in Developmental Endocrinology and Genetics, Section on Molecular Dysmorphology, 10 Center Drive, Bld 10, CRC, Rm 2571, Bethesda, MD 20892,
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Witsch-Baumgartner M, Lanthaler B. Birthday of a syndrome: 50 years anniversary of Smith-Lemli-Opitz Syndrome. Eur J Hum Genet 2014; 23:277-8. [PMID: 24824134 DOI: 10.1038/ejhg.2014.87] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Martina Witsch-Baumgartner
- Department of Medical Genetics, Molecular and Clinical Pharmacology, Division of Human Genetics, Innsbruck, Austria
| | - Barbara Lanthaler
- Department of Medical Genetics, Molecular and Clinical Pharmacology, Division of Human Genetics, Innsbruck, Austria
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Sparks S, Wassif C, Goodwin H, Conley S, Lanham D, Kratz L, Hyland K, Gropman A, Tierney E, Porter F. Decreased cerebral spinal fluid neurotransmitter levels in Smith-Lemli-Opitz syndrome. J Inherit Metab Dis 2014; 37:415-20. [PMID: 24500076 PMCID: PMC4166510 DOI: 10.1007/s10545-013-9672-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 12/10/2013] [Accepted: 12/13/2013] [Indexed: 12/11/2022]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive, multiple congenital anomaly syndrome with cognitive impairment and a distinct behavioral phenotype that includes autistic features. SLOS is caused by a defect in 3β-hydroxysterol Δ(7)-reductase which leads to decreased cholesterol levels and elevated cholesterol precursors, specifically 7- and 8-dehydrocholesterol. However, the pathological processes contributing to the neurological abnormalities in SLOS have not been defined. In view of prior data suggesting defects in SLOS in vesicular release and given the association of altered serotonin metabolism with autism, we were interested in measuring neurotransmitter metabolite levels in SLOS to assess their potential to be used as biomarkers in therapeutic trials. We measured cerebral spinal fluid levels of serotonin and dopamine metabolites, 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) respectively, in 21 SLOS subjects. Results were correlated with the SLOS anatomical severity score, Aberrant Behavior Checklist scores and concurrent sterol biochemistry. Cerebral spinal fluid (CSF) levels of both 5HIAA and HVA were significantly reduced in SLOS subjects. In individual patients, the levels of both 5HIAA and HVA were reduced to a similar degree. CSF neurotransmitter metabolite levels did not correlate with either CSF sterols or behavioral measures. This is the first study demonstrating decreased levels of CSF neurotransmitter metabolites in SLOS. We propose that decreased levels of neurotransmitters in SLOS are caused by a sterol-related defect in synaptic vesicle formation and that CSF 5HIAA and HVA will be useful biomarkers in development of future therapeutic trials.
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Affiliation(s)
- S.E. Sparks
- Clinical Genetics, Department of Pediatrics, Carolinas Medical Center, Charlotte, NC, USA
| | - C.A. Wassif
- Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - H. Goodwin
- Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - S.K. Conley
- Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - D.C. Lanham
- Department of Psychiatry, Kennedy Krieger Institute, Baltimore, MD, USA
| | - L.E. Kratz
- Biochemical Genetics Laboratory, Kennedy Krieger Institute, Baltimore, MD, USA
| | - K. Hyland
- Medical Neurogenetics, Atlanta, GA, USA
| | - A. Gropman
- Center for Neuroscience Research, Children's National Medical Center, Washington, DC, USA
| | - E. Tierney
- Department of Psychiatry, Kennedy Krieger Institute, Baltimore, MD, USA
| | - F.D. Porter
- Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- Corresponding Author: Forbes D. Porter, MD, PhD, 10-CRC, Rm. 5-2571, 10 Center Dr., Bethesda, MD 20892, Phone: 301-435-4432, Fax: 301-480-5791,
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Mutation of 3-hydroxy-3-methylglutaryl CoA synthase I reveals requirements for isoprenoid and cholesterol synthesis in oligodendrocyte migration arrest, axon wrapping, and myelin gene expression. J Neurosci 2014; 34:3402-12. [PMID: 24573296 DOI: 10.1523/jneurosci.4587-13.2014] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Myelin membrane, which ensheaths axons, has an unusually high amount of cholesterol. Cholesterol influences membrane fluidity and assembles lipid-rich microdomains within membranes, and some studies have shown that cholesterol is important for myelination. How cholesterol influences the development and differentiation of oligodendrocytes, glial cells that make myelin, is not known nor is clear whether isoprenoids, which also are products of the cholesterol biosynthetic pathway, contribute to myelination. Through a forward genetic screen in zebrafish we discovered that mutation of hmgcs1, which encodes an enzyme necessary for isoprenoid and cholesterol synthesis, causes oligodendrocyte progenitor cells (OPCs) to migrate past their target axons and to fail to express myelin genes. Drawing on a combination of pharmacological inhibitor and rescue experiments, we provide evidence that isoprenoids and protein prenylation, but not cholesterol, are required in OPCs to halt their migration at target axons. On the other hand, cholesterol, but not isoprenoids, is necessary both for axon ensheathment and myelin gene expression. Our data reveal that different products of the cholesterol biosynthetic pathway have distinct roles in oligodendrocyte development and that they together help to coordinate directed migration, axon wrapping, and gene expression.
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