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The Cerebellum in Niemann-Pick C1 Disease: Mouse Versus Man. CEREBELLUM (LONDON, ENGLAND) 2023; 22:102-119. [PMID: 35040097 DOI: 10.1007/s12311-021-01347-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/17/2021] [Indexed: 02/01/2023]
Abstract
Selective neuronal vulnerability is common to most degenerative disorders, including Niemann-Pick C (NPC), a rare genetic disease with altered intracellular trafficking of cholesterol. Purkinje cell dysfunction and loss are responsible for cerebellar ataxia, which is among the prevailing neurological signs of the NPC disease. In this review, we focus on some questions that are still unresolved. First, we frame the cerebellar vulnerability in the context of the extended postnatal time length by which the development of this structure is completed in mammals. In line with this thought, the much later development of cerebellar symptoms in humans is due to the later development and/or maturation of the cerebellum. Hence, the occurrence of developmental events under a protracted condition of defective intracellular cholesterol mobilization hits the functional maturation of the various cell types generating the ground of increased vulnerability. This is particularly consistent with the high cholesterol demand required for cell proliferation, migration, differentiation, and synapse formation/remodeling. Other major questions we address are why the progression of Purkinje cells loss is always from the anterior to the posterior lobes and why cerebellar defects persist in the mouse model even when genetic manipulations can lead to nearly normal survival.
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Völkner C, Liedtke M, Untucht R, Hermann A, Frech MJ. Patient-Specific iPSC-Derived Neural Differentiated and Hepatocyte-like Cells, Carrying the Compound Heterozygous Mutation p.V1023Sfs*15/p.G992R, Present the "Variant" Biochemical Phenotype of Niemann-Pick Type C1 Disease. Int J Mol Sci 2021; 22:ijms222212184. [PMID: 34830064 PMCID: PMC8624182 DOI: 10.3390/ijms222212184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 02/07/2023] Open
Abstract
Niemann–Pick disease type C1 (NP-C1) is a rare lysosomal storage disorder caused by autosomal recessive mutations in the NPC1 gene. Patients display a wide spectrum on the clinical as well as on the molecular level, wherein a so-called “variant” biochemical phenotype can be observed. Here, we report an in vitro analysis of fibroblasts obtained from an NP-C1 patient carrying the undescribed compound heterozygous mutation p.V1023Sfs*15/p.G992R. Since NP-C1 is a neurovisceral disease and the patient suffers from severe neurological as well as hepatic symptoms, we extended our study to neural differentiated and hepatocyte-like cells derived from patient-specific induced pluripotent stem cells. We detected slightly increased intracellular cholesterol levels compared to the control cell line in fibroblasts, neural differentiated and hepatocyte-like cells, suggesting a “variant” biochemical phenotype. Furthermore, the total NPC1 protein, as well as post-ER glycoforms of the NPC1 protein, tended to be reduced. In addition, colocalization analysis revealed a mild reduction of the NPC1 protein in the lysosomes. The patient was diagnosed with NP-C1 at the age of 34 years, after an initial misdiagnosis of schizophrenia. After years of mild and unspecific symptoms, such as difficulties in coordination and concentration, symptoms progressed and the patient finally presented with ataxia, dysarthria, dysphagia, vertical supranuclear gaze palsy, and hepatosplenomegaly. Genetic testing finally pointed towards an NP-C1 diagnosis, revealing the so-far undescribed compound heterozygous mutation p.V1023Sfs*15/p.G992R in the NPC1 gene. In light of these findings, this case provides support for the p.G992R mutation being causative for a “variant” biochemical phenotype leading to an adult-onset type of NP-C1 disease.
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Affiliation(s)
- Christin Völkner
- Translational Neurodegeneration Section “Albrecht Kossel”, Department of Neurology, University Medical Center Rostock, 18147 Rostock, Germany; (C.V.); (M.L.); (A.H.)
| | - Maik Liedtke
- Translational Neurodegeneration Section “Albrecht Kossel”, Department of Neurology, University Medical Center Rostock, 18147 Rostock, Germany; (C.V.); (M.L.); (A.H.)
| | - Robert Untucht
- Department of Neurology, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany;
| | - Andreas Hermann
- Translational Neurodegeneration Section “Albrecht Kossel”, Department of Neurology, University Medical Center Rostock, 18147 Rostock, Germany; (C.V.); (M.L.); (A.H.)
- Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, 18147 Rostock, Germany
- German Center for Neurodegenerative Diseases (DZNE) Rostock/Greifswald, 18147 Rostock, Germany
| | - Moritz J. Frech
- Translational Neurodegeneration Section “Albrecht Kossel”, Department of Neurology, University Medical Center Rostock, 18147 Rostock, Germany; (C.V.); (M.L.); (A.H.)
- Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, 18147 Rostock, Germany
- Correspondence:
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Benussi A, Cotelli MS, Padovani A, Borroni B. Recent neuroimaging, neurophysiological, and neuropathological advances for the understanding of NPC. F1000Res 2018; 7:194. [PMID: 29511534 PMCID: PMC5814740 DOI: 10.12688/f1000research.12361.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/13/2018] [Indexed: 12/20/2022] Open
Abstract
Niemann–Pick disease type C (NPC) is a rare autosomal recessive lysosomal storage disorder with extensive biological, molecular, and clinical heterogeneity. Recently, numerous studies have tried to shed light on the pathophysiology of the disease, highlighting possible disease pathways common to other neurodegenerative disorders, such as Alzheimer’s disease and frontotemporal dementia, and identifying possible candidate biomarkers for disease staging and response to treatment. Miglustat, which reversibly inhibits glycosphingolipid synthesis, has been licensed in the European Union and elsewhere for the treatment of NPC in both children and adults. A number of ongoing clinical trials might hold promise for the development of new treatments for NPC. The objective of the present work is to review and evaluate recent literature data in order to highlight the latest neuroimaging, neurophysiological, and neuropathological advances for the understanding of NPC pathophysiology. Furthermore, ongoing developments in disease-modifying treatments will be briefly discussed.
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Affiliation(s)
- Alberto Benussi
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia BS, Italy
| | | | - Alessandro Padovani
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia BS, Italy
| | - Barbara Borroni
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia BS, Italy
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De Castro-Orós I, Irún P, Cebolla JJ, Rodriguez-Sureda V, Mallén M, Pueyo MJ, Mozas P, Dominguez C, Pocoví M. Assessment of plasma chitotriosidase activity, CCL18/PARC concentration and NP-C suspicion index in the diagnosis of Niemann-Pick disease type C: a prospective observational study. J Transl Med 2017; 15:43. [PMID: 28222799 PMCID: PMC5320753 DOI: 10.1186/s12967-017-1146-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/09/2017] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Niemann-Pick disease type C (NP-C) is a rare, autosomal recessive neurodegenerative disease caused by mutations in either the NPC1 or NPC2 genes. The diagnosis of NP-C remains challenging due to the non-specific, heterogeneous nature of signs/symptoms. This study assessed the utility of plasma chitotriosidase (ChT) and Chemokine (C-C motif) ligand 18 (CCL18)/pulmonary and activation-regulated chemokine (PARC) in conjunction with the NP-C suspicion index (NP-C SI) for guiding confirmatory laboratory testing in patients with suspected NP-C. METHODS In a prospective observational cohort study, incorporating a retrospective determination of NP-C SI scores, two different diagnostic approaches were applied in two separate groups of unrelated patients from 51 Spanish medical centers (n = 118 in both groups). From Jan 2010 to Apr 2012 (Period 1), patients with ≥2 clinical signs/symptoms of NP-C were considered 'suspected NP-C' cases, and NPC1/NPC2 sequencing, plasma chitotriosidase (ChT), CCL18/PARC and sphingomyelinase levels were assessed. Based on findings in Period 1, plasma ChT and CCL18/PARC, and NP-C SI prediction scores were determined in a second group of patients between May 2012 and Apr 2014 (Period 2), and NPC1 and NPC2 were sequenced only in those with elevated ChT and/or elevated CCL18/PARC and/or NP-C SI ≥70. Filipin staining and 7-ketocholesterol (7-KC) measurements were performed in all patients with NP-C gene mutations, where possible. RESULTS In total across Periods 1 and 2, 10/236 (4%) patients had a confirmed diagnosis o NP-C based on gene sequencing (5/118 [4.2%] in each Period): all of these patients had two causal NPC1 mutations. Single mutant NPC1 alleles were detected in 8/236 (3%) patients, overall. Positive filipin staining results comprised three classical and five variant biochemical phenotypes. No NPC2 mutations were detected. All patients with NPC1 mutations had high ChT activity, high CCL18/PARC concentrations and/or NP-C SI scores ≥70. Plasma 7-KC was higher than control cut-off values in all patients with two NPC1 mutations, and in the majority of patients with single mutations. Family studies identified three further NP-C patients. CONCLUSION This approach may be very useful for laboratories that do not have mass spectrometry facilities and therefore, they cannot use other NP-C biomarkers for diagnosis.
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Affiliation(s)
- Isabel De Castro-Orós
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain. .,Instituto de Investigación Sanitaria Aragón (IIS Aragón), Saragossa, Spain.
| | - Pilar Irún
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain.,Instituto de Investigación Sanitaria Aragón (IIS Aragón), Saragossa, Spain.,Centro de Investigación Biomédica en Red (CIBERER), Instituto de Salud Carlos III, Saragossa, Spain
| | - Jorge Javier Cebolla
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain.,Spanish Foundation for the Study and Therapy of Gaucher Disease, Saragossa, Spain
| | - Victor Rodriguez-Sureda
- Centro de Investigación Biomédica en Red (CIBERER), Instituto de Salud Carlos III, Saragossa, Spain.,Biochemistry and Molecular Biology Research Centre for Nanomedicine, Vall d'Hebron University Hospital, Barcelona, Spain
| | - Miguel Mallén
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain
| | - María Jesús Pueyo
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain
| | - Pilar Mozas
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain
| | - Carmen Dominguez
- Centro de Investigación Biomédica en Red (CIBERER), Instituto de Salud Carlos III, Saragossa, Spain.,Biochemistry and Molecular Biology Research Centre for Nanomedicine, Vall d'Hebron University Hospital, Barcelona, Spain
| | - Miguel Pocoví
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Science, University of Zaragoza, C. Pedro Cerbuna 12, 50009, Saragossa, Spain.,Instituto de Investigación Sanitaria Aragón (IIS Aragón), Saragossa, Spain
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Jecel J, Harzer K, Paschke E, Beck-Wödl S, Bauer P, Hejtman M, Katzenschlager R. Distinct Niemann-Pick Disease Type C Clinical, Cytological, and Biochemical Phenotype in an Adult Patient With 1 Mutated, Overexpressed NPC1 Allele. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2015. [DOI: 10.1177/2326409815618979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Julia Jecel
- Department of Neurology and Karl Landsteiner Insitute for neuroimmunological and neurodegenerative disorders, Danube Hospital/Donauspital, Langobardenstr. 122, 1220 Vienna, Austria
| | - Klaus Harzer
- Neurometabolic Laboratory, Klinik für Kinder-und Jugendmedizin, University of Tübingen, Hoppe-Seyler-Str.1, 72076 Tübingen, Germany
| | - Eduard Paschke
- Department of Pediatrics, University Hospital Graz, Auenbruggerplatz 34, 8036 Graz, Austria
| | - Stefanie Beck-Wödl
- Department of Medical Genetics, University Hospital Tübingen, Calwerstr. 7, 72076 Tübingen, Germany
| | - Peter Bauer
- Department of Medical Genetics, University Hospital Tübingen, Calwerstr. 7, 72076 Tübingen, Germany
| | - Milos Hejtman
- Department of Laboratory Medicine and Hematology, Danube Hospital/Donauspital, Langobardenstr. 122, 1220 Vienna, Austria
| | - Regina Katzenschlager
- Department of Neurology and Karl Landsteiner Insitute for neuroimmunological and neurodegenerative disorders, Danube Hospital/Donauspital, Langobardenstr. 122, 1220 Vienna, Austria
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6
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Abstract
Niemann Pick disease type C (NP-C) is a rare autosomal recessive disorder that results from mutations in either the NPC1 or the NPC2 gene. The estimated incidence of NP-C is 1 in 120,000 live births, although the frequency of cases is higher in some isolated populations. More than 350 different NPC1 and NPC2 gene mutations have been reported in patients with confirmed diagnoses. Approximately 95 % of patients harbour mutations in NPC1, with most of the remaining patients having NPC2 mutations. The traditional methods for diagnosing patients with NP-C include histopathological analysis of bone marrow aspirate, liver and skin biopsies, fluorescent and electron microscopy, and cholesterol esterification assays. New laboratory methods that use mass spectroscopy for detection of cholesterol metabolism products are promising to become part of the routine diagnostic and screening tests in the near future, but further evaluation is required to determine the sensitivity and specificity of these analyses in patients with different age-at-onset forms of NP-C. Although filipin staining and cholesterol esterification studies performed in patient skin fibroblasts can, in experienced hands, provide a robust approach to diagnosing NP-C, they are only available in a few specialist laboratories. Thus, sequencing of NPC1 and NPC2 is currently the most universally accessible diagnostic technique in this disorder.
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7
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Klinke G, Rohrbach M, Giugliani R, Burda P, Baumgartner MR, Tran C, Gautschi M, Mathis D, Hersberger M. LC-MS/MS based assay and reference intervals in children and adolescents for oxysterols elevated in Niemann-Pick diseases. Clin Biochem 2015; 48:596-602. [PMID: 25819840 DOI: 10.1016/j.clinbiochem.2015.03.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/10/2015] [Accepted: 03/11/2015] [Indexed: 11/25/2022]
Abstract
BACKGROUND Niemann-Pick type C (NP-C) is a rare progressive neurodegenerative lipid storage disorder with heterogeneous clinical presentation and challenging diagnostic procedures. Recently oxysterols have been reported to be specific biomarkers for NP-C but knowledge on the intra-individual variation and on reference intervals in children and adolescents are lacking. METHODS We established a LC-MS/MS assay to measure Cholestane-3β, 5α, 6β-triol (C-triol) and 7-Ketocholesterol (7-KC) following Steglich esterification. To assess reference intervals and intra-individual variation we determined oxysterols in 148 children and adolescents from 0 to 18 years and repeat measurements in 19 of them. RESULTS The reported method is linear (r>0.99), sensitive (detection limit of 0.03 ng/mL [0.07 nM] for C-triol, and 0.54 ng/mL [1.35 nM] for 7-KC) and precise, with an intra-day imprecision of 4.8% and 4.1%, and an inter-day imprecision of 7.0% and 11.0% for C-triol (28 ng/ml, 67 nM) and 7-KC (32 ng/ml, 80 nM), respectively. Recoveries for 7-KC and C-triol range between 93% and 107%. The upper reference limit obtained for C-triol is 40.4 ng/mL (95% CI: 26.4-61.7 ng/mL, 96.0 nM, 95% CI: 62.8-146.7 nM) and 75.0 ng/mL for 7-KC (95% CI: 55.5-102.5 ng/mL, 187.2 nM, 95% CI: 138.53-255.8 nM), with no age or gender dependency. Both oxysterols have a broad intra-individual variation of 46%±23% for C-triol and 52%±29% for 7-KC. Nevertheless, all Niemann-Pick patients showed increased C-triol levels including Niemann-Pick type A and B patients. CONCLUSIONS The LC-MS/MS assay is a robust assay to quantify C-triol and 7-KC in plasma with well documented reference intervals in children and adolescents to screen for NP-C in the pediatric population. In addition our results suggest that especially the C-triol is a biomarker for all three Niemann-Pick diseases.
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Affiliation(s)
- Glynis Klinke
- Division of Clinical Chemistry and Biochemistry, Children's Research Center, University Children's Hospital Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Marianne Rohrbach
- Division of Metabolism, Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Roberto Giugliani
- Medical Genetics Service, HCPA, Porto Alegre, Brazil; Department of Genetics, UFRGS, Porto Alegre, Brazil
| | - Patricie Burda
- Division of Metabolism, Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Matthias R Baumgartner
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Division of Metabolism, Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Christel Tran
- Center for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland
| | - Matthias Gautschi
- Paediatric Endocrinology, Diabetology and Metabolism, University Children's Hospital Bern, Switzerland; University Institute of Clinical Chemistry, Inselspital Bern, Switzerland
| | - Déborah Mathis
- Division of Clinical Chemistry and Biochemistry, Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Martin Hersberger
- Division of Clinical Chemistry and Biochemistry, Children's Research Center, University Children's Hospital Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
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Patterson MC, Hendriksz CJ, Walterfang M, Sedel F, Vanier MT, Wijburg F. Recommendations for the diagnosis and management of Niemann-Pick disease type C: an update. Mol Genet Metab 2012; 106:330-44. [PMID: 22572546 DOI: 10.1016/j.ymgme.2012.03.012] [Citation(s) in RCA: 312] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2012] [Revised: 03/16/2012] [Accepted: 03/16/2012] [Indexed: 12/18/2022]
Abstract
Niemann-Pick disease type C (NP-C) is a rare inherited neurovisceral disease caused by mutations in either the NPC1 (in 95% of cases) or the NPC2 gene (in around 5% of cases), which lead to impaired intracellular lipid trafficking and accumulation of cholesterol and glycosphingolipids in the brain and other tissues. Characteristic neurological manifestations of NP-C include saccadic eye movement (SEM) abnormalities or vertical supranuclear gaze palsy (VSGP), cerebellar signs (ataxia, dystonia/dysmetria, dysarthria and dysphagia) and gelastic cataplexy. Epileptic seizures are also common in affected patients. Typically, neurological disease onset occurs during childhood, although an increasing number of cases are being detected and diagnosed during adulthood based on late-onset neurological signs and psychiatric manifestations. Categorization of patients according to age at onset of neurological manifestations (i.e. early-infantile, late-infantile, juvenile and adolescent/adult-onset) can be useful for the evaluation of disease course and treatment responses. The first international guidelines for the clinical management of NP-C in children and adults were published in 2009. Since that time a significant amount of data regarding the epidemiology, detection/diagnosis, and treatment of NP-C has been published. Here, we report points of consensus among experts in the diagnosis and treatment of NP-C based on a follow-up meeting in Paris, France in September 2011. This article serves as an update to the original guidelines providing, among other things, further information on detection/diagnostic methods, potential new methods of monitoring disease progression, and therapy. Treatment goals and the application of disease-specific therapy with miglustat are also re-evaluated.
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Tängemo C, Weber D, Theiss S, Mengel E, Runz H. Niemann-Pick Type C disease: characterizing lipid levels in patients with variant lysosomal cholesterol storage. J Lipid Res 2011; 52:813-25. [PMID: 21245028 DOI: 10.1194/jlr.p013524] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A central feature of Niemann-Pick Type C (NPC) disease is sequestration of cholesterol and glycosphingolipids in lysosomes. A large phenotypic variability, on both a clinical as well as a molecular level, challenges NPC diagnosis. For example, substantial difficulties in identifying or excluding NPC in a patient exist in cases with a "variant" biochemical phenotype, where cholesterol levels in cultured fibroblasts, the primary diagnostic indicator, are only moderately elevated. Here we apply quantitative microscopy as an accurate and objective diagnostic tool to measure cholesterol accumulation at the level of single cells. When employed to characterize cholesterol enrichment in fibroblasts from 20 NPC patients and 11 controls, considerable heterogeneity became evident both within the population of cells cultured from one individual as well as between samples from different probands. An obvious correlation between biochemical phenotype and clinical disease course was not apparent from our dataset. However, plasma levels of HDL-cholesterol (HDL-c) tended to be in the normal range in patients with a "variant" as opposed to a "classic" biochemical phenotype. Attenuated lysosomal cholesterol accumulation in "variant" cells was associated with detectable NPC1 protein and residual capability to upregulate expression of ABCA1 in response to LDL. Taken together, our approach opens perspectives not only to support diagnosis, but also to better characterize mechanisms impacting cholesterol accumulation in NPC patient-derived cells.
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Affiliation(s)
- Carolina Tängemo
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
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10
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Vanier MT. Niemann-Pick disease type C. Orphanet J Rare Dis 2010; 5:16. [PMID: 20525256 PMCID: PMC2902432 DOI: 10.1186/1750-1172-5-16] [Citation(s) in RCA: 777] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 06/03/2010] [Indexed: 12/12/2022] Open
Abstract
Niemann-Pick C disease (NP-C) is a neurovisceral atypical lysosomal lipid storage disorder with an estimated minimal incidence of 1/120 000 live births. The broad clinical spectrum ranges from a neonatal rapidly fatal disorder to an adult-onset chronic neurodegenerative disease. The neurological involvement defines the disease severity in most patients but is typically preceded by systemic signs (cholestatic jaundice in the neonatal period or isolated spleno- or hepatosplenomegaly in infancy or childhood). The first neurological symptoms vary with age of onset: delay in developmental motor milestones (early infantile period), gait problems, falls, clumsiness, cataplexy, school problems (late infantile and juvenile period), and ataxia not unfrequently following initial psychiatric disturbances (adult form). The most characteristic sign is vertical supranuclear gaze palsy. The neurological disorder consists mainly of cerebellar ataxia, dysarthria, dysphagia, and progressive dementia. Cataplexy, seizures and dystonia are other common features. NP-C is transmitted in an autosomal recessive manner and is caused by mutations of either the NPC1 (95% of families) or the NPC2 genes. The exact functions of the NPC1 and NPC2 proteins are still unclear. NP-C is currently described as a cellular cholesterol trafficking defect but in the brain, the prominently stored lipids are gangliosides. Clinical examination should include comprehensive neurological and ophthalmological evaluations. The primary laboratory diagnosis requires living skin fibroblasts to demonstrate accumulation of unesterified cholesterol in perinuclear vesicles (lysosomes) after staining with filipin. Pronounced abnormalities are observed in about 80% of the cases, mild to moderate alterations in the remainder ("variant" biochemical phenotype). Genotyping of patients is useful to confirm the diagnosis in the latter patients and essential for future prenatal diagnosis. The differential diagnosis may include other lipidoses; idiopathic neonatal hepatitis and other causes of cholestatic icterus should be considered in neonates, and conditions with cerebellar ataxia, dystonia, cataplexy and supranuclear gaze palsy in older children and adults. Symptomatic management of patients is crucial. A first product, miglustat, has been granted marketing authorization in Europe and several other countries for specific treatment of the neurological manifestations. The prognosis largely correlates with the age at onset of the neurological manifestations.
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Affiliation(s)
- Marie T Vanier
- Institut National de la Santé et de la Recherche Médicale, Unité 820, Faculté de Médecine Lyon-Est Claude Bernard, 7 Rue G, Paradin, F-69008, Lyon, France.
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11
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Garver WS, Jelinek D, Francis GA, Murphy BD. The Niemann-Pick C1 gene is downregulated by feedback inhibition of the SREBP pathway in human fibroblasts. J Lipid Res 2008; 49:1090-102. [PMID: 18272927 DOI: 10.1194/jlr.m700555-jlr200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Niemann-Pick C1 (NPC1) protein regulates the transport of cholesterol from late endosomes/lysosomes to other compartments responsible for maintaining intracellular cholesterol homeostasis. The present study examined the expression of the NPC1 gene and the distribution of the NPC1 protein that resulted from the transport of LDL-derived cholesterol through normal human fibroblasts. A key finding was that the transport of cholesterol from late endosomes/lysosomes to the sterol-regulatory pool at the endoplasmic reticulum, as determined by feedback inhibition of the sterol-regulatory element binding protein (SREBP) pathway, was associated with the downregulation of the NPC1 gene. Consistent with these results, fibroblasts incubated with LDL had decreased amounts of SREBP protein that interacted with sterol-regulatory element (SRE) sequences positioned within the NPC1 gene promoter region. Finally, partial colocalization of the NPC1 protein with late endosomes/lysosomes and distinct regions of the endoplasmic reticulum suggested that the NPC1 protein may facilitate the transport of cholesterol directly between these two compartments. Together, these results indicate that the transport of LDL-derived cholesterol from late endosomes/lysosomes to the sterol-regulatory pool, known to be regulated by the NPC1 protein, is responsible for promoting feedback inhibition of the SREBP pathway and downregulation of the NPC1 gene.
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Affiliation(s)
- William S Garver
- Department of Pediatrics, University of Arizona, Tucson, AZ 85724-5037, USA.
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12
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Abstract
Lysosomal sequestration of endocytosed LDL-derived cholesterol, premature and abnormal enrichment of cholesterol in trans Golgi cisternae and accompanying anomalies in intracellular sterol trafficking are the hallmark phenotypic features of the Niemann-Pick C (NPC) lesion. A variable severity of these alterations has been observed, with only partial correlation between clinical and biochemical phenotypes. NPC also affects the metabolism of sphingolipids, and other biochemical abnormalities have been reported. Occurrence of neurofibrillary tangles in the brain of patients with a slowly progressive course is a recent intriguing observation. Genetic heterogeneity was established by cell hybridization and linkage studies. The two complementation groups could not be distinguished from each other by clinical, cellular or biochemical criteria, suggesting that the two gene products may interact or function sequentially. The major (> 90% of patients) NPC1 gene was mapped to 18q11 and recently isolated by positional cloning. The cDNA sequence predicts a 1278-amino acid protein, with 13 to 16 possible transmembrane regions and a putative cholesterol-sensing domain. Two murine models of the disease involving the same gene are known. The murine cDNA and the npc(nih) mutation have been characterized. Described homologies of the NPC1 protein are in line with its putative involvement in cellular cholesterol traffic.
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Affiliation(s)
- M T Vanier
- INSERM Unit 189, Lyon-Sud Medical School, Oullins, France.
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13
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Choi HY, Karten B, Chan T, Vance JE, Greer WL, Heidenreich RA, Garver WS, Francis GA. Impaired ABCA1-dependent lipid efflux and hypoalphalipoproteinemia in human Niemann-Pick type C disease. J Biol Chem 2003; 278:32569-77. [PMID: 12813037 DOI: 10.1074/jbc.m304553200] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cholesterol trafficking defect in Niemann-Pick type C (NPC) disease leads to impaired regulation of cholesterol esterification, cholesterol synthesis, and low density lipoprotein receptor activity. The ATP-binding cassette transporter A1 (ABCA1), which mediates the rate-limiting step in high density lipoprotein (HDL) particle formation, is also regulated by cell cholesterol content. To determine whether the Niemann-Pick C1 protein alters the expression and activity of ABCA1, we determined the ability of apolipoprotein A-I (apoA-I) to deplete pools of cellular cholesterol and phospholipids in human fibroblasts derived from NPC1+/+, NPC1+/-, and NPC1-/- subjects. Efflux of low density lipoprotein-derived, non-lipoprotein, plasma membrane, and newly synthesized pools of cell cholesterol by apoA-I was diminished in NPC1-/- cells, as was efflux of phosphatidylcholine and sphingomyelin. NPC1+/- cells showed intermediate levels of lipid efflux compared with NPC1+/+ and NPC1-/- cells. Binding of apoA-I to cholesterol-loaded and non-cholesterol-loaded cells was highest for NPC1+/- cells, with NPC1+/+ and NPC1-/- cells showing similar levels of binding. ABCA1 mRNA and protein levels increased in response to cholesterol loading in NPC1+/+ and NPC1+/- cells but showed low levels at base line and in response to cholesterol loading in NPC1-/- cells. Consistent with impaired ABCA1-dependent lipid mobilization to apoA-I for HDL particle formation, we demonstrate for the first time decreased plasma HDL-cholesterol levels in 17 of 21 (81%) NPC1-/- subjects studied. These results indicate that the cholesterol trafficking defect in NPC disease results in reduced activity of ABCA1, which we suggest is responsible for the low HDL-cholesterol in the majority of NPC subjects and partially responsible for the overaccumulation of cellular lipids in this disorder.
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Affiliation(s)
- Hong Y Choi
- Department of Medicine and the Canadian Institutes of Health Research Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
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Liscum L, Arnio E, Anthony M, Howley A, Sturley SL, Agler M. Identification of a pharmaceutical compound that partially corrects the Niemann-Pick C phenotype in cultured cells. J Lipid Res 2002; 43:1708-17. [PMID: 12364555 DOI: 10.1194/jlr.m200179-jlr200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Niemann-Pick C (NPC) is an autosomal recessive lysosomal lipid storage disease characterized by progressive central nervous system degeneration. In cultured human NPC fibroblasts, LDL-derived cholesterol accumulates in lysosomes and endosomes, LDL-cholesterol transport from endocytic compartments to other cellular compartments is delayed, and LDL does not elicit normal homeostatic responses. Currently, there is no therapy that delays the onset of neurological symptoms or prolongs the life span of NPC children. We have developed and implemented an amphotericin B-mediated cytotoxicity assay to screen for potential therapeutic drugs that induce cholesterol movement in cultured NPC cells. NPC cells are relatively resistant to amphotericin B killing due to intracellular sequestration of cellular cholesterol. The screen was carried out using simian virus 40-transformed ovarian granulosa cells from the npc (nih) mouse model of NPC disease. A library of 44240 compounds was screened and 55 compounds were identified that promote amphotericin B-mediated killing of NPC cells. One compound, NP-27, corrected the NPC phenotype by four different measures of cholesterol homeostasis. In addition to making NPC cells more sensitive to amphotericin B, NP-27 stimulated two separate cholesterol transport pathways and restored LDL stimulation of cholesterol esterification to near normal levels.
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Affiliation(s)
- Laura Liscum
- Department of Physiology, Tufts University School of Medicine, Boston, MA 02111, USA.
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15
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Lange Y, Ye J, Rigney M, Steck T. Cholesterol movement in Niemann-Pick type C cells and in cells treated with amphiphiles. J Biol Chem 2000; 275:17468-75. [PMID: 10751394 DOI: 10.1074/jbc.m000875200] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cholesterol accumulates to massive levels in cells from Niemann-Pick type C (NP-C) patients and in cells treated with class 2 amphiphiles that mimic NP-C disease. This behavior has been attributed to the failure of cholesterol released from ingested low density lipoproteins to exit the lysosomes. However, we now show that the rate of movement of cholesterol from lysosomes to plasma membranes in NP-C cells is at least as great as normal, as was also found previously for amphiphile-treated cells. Furthermore, the lysosomes in these cells filled with plasma membrane cholesterol in the absence of lipoproteins. In addition, we showed that the size of the endoplasmic reticulum cholesterol pool and the set point of the homeostatic sensor of cell cholesterol were approximately normal in NP-C cells. The plasma membrane cholesterol pools in both NP-C and amphiphile-treated cells were also normal. Furthermore, the build up of cholesterol in NP-C lysosomes was not a physiological response to cholesterol overload. Rather, it appeared that the accumulation in NP-C lysosomes results from an imbalance in the brisk flow of cholesterol among membrane compartments. In related experiments, we found that NP-C cells did not respond to class 2 amphiphiles (e.g. trifluoperazine, imipramine, and U18666A); these agents may therefore act directly on the NPC1 protein or on its pathway. Finally, we showed that the lysosomal cholesterol pool in NP-C cells was substantially and preferentially reduced by incubating cells with the oxysterols, 25-hydroxycholesterol and 7-ketocholesterol; these findings suggest a new pharmacological approach to the treatment of NP-C disease.
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Affiliation(s)
- Y Lange
- Department of Pathology, Rush-Presbyterian-St. Luke's Medical Center University of Chicago, Chicago, Illinois 60637, USA.
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16
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vom Dahl S, Harzer K, Rolfs A, Albrecht B, Niederau C, Vogt C, van Weely S, Aerts J, Müller G, Häussinger D. Hepatosplenomegalic lipidosis: what unless Gaucher? Adult cholesteryl ester storage disease (CESD) with anemia, mesenteric lipodystrophy, increased plasma chitotriosidase activity and a homozygous lysosomal acid lipase -1 exon 8 splice junction mutation. J Hepatol 1999; 31:741-6. [PMID: 10551400 DOI: 10.1016/s0168-8278(99)80356-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A 36-year-old woman was admitted for hepatosplenomegaly and anemia. Bone marrow cytology showed "sea-blue histiocytes", vacuolated macrophages and plasma cells. As primary liver disease, malignancy or hematologic disorders were excluded, and plasma chitotriosidase activity was increased 27-fold over control, the presence of a lysosomal storage disease was suspected. Biochemical analysis of skin fibroblasts revealed normal glucocerebrosidase and sphingomyelinase activity, but lipid analysis showed a more than 15-fold accumulation of cholesterol esters within the cells. The activity of lysosomal acid lipase (LAL) in fibroblast homogenates was decreased to 12% of control subjects. Mutational analysis of the patient's blood showed the homozygous G-->A mutation at position -1 of the exon 8 splice donor site (E8SJM-allele) known for adult cholesteryl ester storage disease (CESD); the polymorphic background was that of the complex haplotype -6Thr, 2Gly, 894 G-->A. Based on clinical, laboratory, cytological and and biochemical findings, CESD can clearly be separated from other more frequent inherited lysosomal storage diseases, e.g. atypical forms of Gaucher disease.
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Affiliation(s)
- S vom Dahl
- Division of Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Düsseldorf, Germany
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17
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Wood WG, Schroeder F, Avdulov NA, Chochina SV, Igbavboa U. Recent advances in brain cholesterol dynamics: transport, domains, and Alzheimer's disease. Lipids 1999; 34:225-34. [PMID: 10230715 DOI: 10.1007/s11745-999-0357-9] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Major advances in understanding cholesterol dynamics and the role that cholesterol plays in vascular disease have recently been made. The brain is an organ that is highly enriched in cholesterol, but progress toward understanding brain cholesterol dynamics has been relatively limited. This review examines recent contributions to the understanding of brain cholesterol dynamics, focusing on extracellular and intracellular lipid carrier proteins, membrane cholesterol domains, and emerging evidence linking an association between cholesterol dynamics and Alzheimer's disease.
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Affiliation(s)
- W G Wood
- Geriatric Research, Education and Clinical Center, Veterans Administration Medical Center and the Department of Pharmacology, University of Minnesota School of Medicine, Minneapolis 55417, USA
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18
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A second complementation class of cholesterol transport mutants with a variant Niemann-Pick type C phenotype. J Lipid Res 1994. [DOI: 10.1016/s0022-2275(20)39779-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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19
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Pentchev PG, Blanchette-Mackie EJ, Dawidowicz EA. The NP-C gene: a key to pathways of intracellular cholesterol transport. Trends Cell Biol 1994; 4:365-9. [PMID: 14731625 DOI: 10.1016/0962-8924(94)90086-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Elucidation of the pathways for intracellular transport of cholesterol is an important yet elusive goal in cell biology. Analysis of the cellular defects in the human disease Niemann-Pick C (NP-C) is providing insights into this problem. Cholesterol derived from low-density lipoprotein accumulates in lysosomes of NP-C cells, apparently because intracellular movement of such cholesterol is blocked. Identification of the NP-C gene should provide crucial molecular clues to the mechanism of cholesterol transport within cells.
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Affiliation(s)
- P G Pentchev
- Molecular and Cellular Pathophysiology Section, Developmental and Metabolic Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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Byers DM, Douglas JA, Cook HW, Palmer FB, Ridgway ND. Regulation of intracellular cholesterol metabolism is defective in lymphoblasts from Niemann-Pick type C and type D patients. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1226:173-80. [PMID: 8204665 DOI: 10.1016/0925-4439(94)90026-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Regulation of intracellular cholesterol metabolism has been studied in Epstein-Barr virus-transformed lymphoblasts from patients with Niemann-Pick type C (NPC) and the Nova Scotia type D (NPD) disease. Addition of LDL to normal lymphoblasts cultured in lipoprotein-deficient medium increased cholesterol esterification 10-fold (to a maximum of 1.0 nmol/h/mg protein at 15 h), while little stimulation was seen in NPC cells. The response by NPD lymphoblasts was intermediate, reaching approximately half of normal values by 14-24 h. Lymphoblasts from both NPC and NPD obligate heterozygotes exhibited 50% of normal LDL-stimulated cholesterol esterification at 6 h, when activity was < 10% of normal values in patient cells. Fluorescence staining with filipin indicated excessive intracellular accumulation of LDL-derived cholesterol in both NPC and NPD lymphoblasts. Downregulation of LDL receptor mRNA levels by LDL, measured by S1 nuclease protection assay, was also impaired in NP lymphoblasts and fibroblasts (NPC > NPD), although a similar rate of receptor protein down-regulation by LDL (t1/2 = 10-15 h) was observed in normal and NP lymphoblasts. In contrast, LDL down-regulation of 3-hydroxy-3-methylglutaryl-CoA reductase mRNA did not appear to be affected in NP cells: LDL produced a 3-fold (lymphoblasts) or > 10-fold (fibroblasts) decrease by 12 h in both normal and affected cells. Thus, NPC and NPD lymphoblasts exhibit distinct defects in cholesterol esterification and storage, similar to those observed in mutant fibroblasts. Other regulatory responses are also impaired in NPC lymphoblasts but appear to be less affected in NPD cells. Lymphoblasts should provide a valuable immortalized cell line model for study of defective regulation of cholesterol esterification and transport in Niemann-Pick type II disease, and may also be suitable for diagnosis and carrier detection.
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Affiliation(s)
- D M Byers
- Atlantic Research Centre, Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
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van de Vlasakker CJ, Gabreëls FJ, Wijburg HC, Wevers RA. Clinical features of Niemann-Pick disease type C. An example of the delayed onset, slowly progressive phenotype and an overview of recent literature. Clin Neurol Neurosurg 1994; 96:119-23. [PMID: 7924073 DOI: 10.1016/0303-8467(94)90044-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Analysis of recent literature on Niemann-Pick disease type C (NPC) reveals a broad clinical spectrum with diverse neurological manifestations. Diagnosis and assessment are discussed. We present a case with symptomatology that is in concordance with a specific phenotype. The major clinical features are highlighted in a review of recently published cases. NPC could be underdiagnosed and we argue that in the work-up of progressive neurological disorders NPC should be seriously considered, at all ages, whenever there is any combination of visceromegaly, psychomotor deterioration, ataxia, vertical gaze disturbances or developmental delay. The Filipine staining of fibroblasts is a helpful asset in the diagnostic process, to be concluded with the detection of defective intracellular cholesterol esterification.
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Weintraub H, Alroy J, DeGasperi R, Goyal V, Skutelsky E, Pentchev PG, Warren CD. Storage of glycoprotein in NCTR-Balb/C mouse. Lectin histochemistry, and biochemical studies. ACTA ACUST UNITED AC 1993; 62:347-52. [PMID: 1360721 DOI: 10.1007/bf02899702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A strain of Balb/C mice carrying a lysosomal storage disorder exhibits metabolic and phenotypic abnormalities similar to patients with sphingomyelin-cholesterol lipidoses type II (i.e., Niemann-Pick C and D). Their foamy cells, which belong to the reticuloendothelial system, stained intensely by periodate-Schiff (PAS) reagent and were resistant to predigestion with diastase. To identify the chemical nature of the PAS-positive storage material, we applied lectin histochemistry and biochemical methods. Paraffin embedded sections, and delipidated frozen tissue sections, were treated with biotinylated lectins and localized with avidin-biotin-peroxidase complex. Araldite-embedded semithin sections were incubated with biotinylated lectins followed by avidin-gold and were enhanced with silver. By both histochemical methods the affected foamy cells stained positively as follows: Concanavalia ensiformis agglutinin, Datura stramonium agglutinin, Griffonia simplicifolia-I, Lens culinaris agglutinin, peanut agglutinin, Ricinus communis agglutinin-I, wheat germ agglutinin (WGA), and succinylated-WGA. Biochemical analysis of liver extracts complemented the histochemical data and demonstrated accumulation of glycoproteins containing polylactosaminoglycans in affected mice. Our findings indicate that the storage material in NCTR-Balb/C mice is heterogeneous. The lipids that are extracted by organic solvents during the histologic preparations mask the occurrence of polylactosaminoglycan containing glycoproteins in native frozen sections.
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Affiliation(s)
- H Weintraub
- Department of Pathology, Sackler School of Medicine, Tel-Aviv University, Israel
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23
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Abstract
The concept of Niemann-Pick disease type C as a secondary sphingomyelin storage disorder (in contrast to the sphingomyelinase-deficient types A and B) has become more and more prevalent, in view of the complex lipid storage pattern and variable sphingomyelinase activities. Although the primary lesion is still unknown, studies conducted over the past six years have led to a breakthrough by showing that this disorder is characterized by unique abnormalities of intracellular translocation of exogenous cholesterol. In cultured fibroblasts of patients, this block leads to a delayed induction of the homeostatic responses to exogenous cholesterol, in particular cholesteryl ester formation, and to the accumulation of unesterified cholesterol in a vesicular, essentially lysosomal, compartment. The transport of endogenous cholesterol is apparently unaffected. The spectrum of phenotypic heterogeneity in relation to abnormal LDL-processing has been defined in a large patient population. Clinical presentation of the disease is also reviewed and biochemical correlations are discussed. This discovery has had immediate medical applications, by providing the first strategy for reliable prenatal diagnosis of the disorder and easy diagnosis of patients. To date, the exact implication of the cholesterol transport defect in the pathogenesis of Niemann-Pick type C is not known; recent observations have opened up new possible approaches for the understanding of this lesion. Although final classification of Niemann-Pick disease type C must await elucidation of the primary defect(s), present knowledge already establishes that the disease is a nosological entity distinct from Niemann-Pick disease type A and B, and suggests that it might be the model for a new molecular concept of neurolipidosis--and even of inherited metabolic disease.
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Affiliation(s)
- M T Vanier
- Department of Biochemistry, INSERM U 189, Faculté de Médecine Lyon-Sud, Oullins, France
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