1
|
Dubot P, Sabourdy F, Levade T. Human genetic defects of sphingolipid synthesis. J Inherit Metab Dis 2024. [PMID: 38706107 DOI: 10.1002/jimd.12745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 04/11/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024]
Abstract
Sphingolipids are ubiquitous lipids, present in the membranes of all cell types, the stratum corneum and the circulating lipoproteins. Autosomal recessive as well as dominant diseases due to disturbed sphingolipid biosynthesis have been identified, including defects in the synthesis of ceramides, sphingomyelins and glycosphingolipids. In many instances, these gene variants result in the loss of catalytic function of the mutated enzymes. Additional gene defects implicate the subcellular localization of the sphingolipid-synthesizing enzyme, the regulation of its activity, or even the function of a sphingolipid-transporter protein. The resulting metabolic alterations lead to two major, non-exclusive types of clinical manifestations: a neurological disease, more or less rapidly progressive, associated or not with intellectual disability, and an ichthyotic-type skin disorder. These phenotypes highlight the critical importance of sphingolipids in brain and skin development and homeostasis. The present article reviews the clinical symptoms, genetic and biochemical alterations, pathophysiological mechanisms and therapeutic options of this relatively novel group of metabolic diseases.
Collapse
Affiliation(s)
- Patricia Dubot
- Unité Mixte de Recherche INSERM 1037, CNRS 5071, Université Toulouse III-Paul Sabatier, Centre de Recherches en Cancérologie de Toulouse (CRCT), Toulouse, France
- Laboratoire de Biochimie, Institut Fédératif de Biologie, CHU Purpan, Toulouse, France
- Centre de Recherches, CHU Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Frédérique Sabourdy
- Unité Mixte de Recherche INSERM 1037, CNRS 5071, Université Toulouse III-Paul Sabatier, Centre de Recherches en Cancérologie de Toulouse (CRCT), Toulouse, France
- Laboratoire de Biochimie, Institut Fédératif de Biologie, CHU Purpan, Toulouse, France
| | - Thierry Levade
- Unité Mixte de Recherche INSERM 1037, CNRS 5071, Université Toulouse III-Paul Sabatier, Centre de Recherches en Cancérologie de Toulouse (CRCT), Toulouse, France
- Laboratoire de Biochimie, Institut Fédératif de Biologie, CHU Purpan, Toulouse, France
| |
Collapse
|
2
|
Chowdhury S, Kumar R, Zepeda E, DeFrees S, Ledeen R. Synthetic GM1 improves motor and memory dysfunctions in mice with monoallelic or biallelic disruption of GM3 synthase. FEBS Open Bio 2023; 13:1651-1657. [PMID: 37401916 PMCID: PMC10476560 DOI: 10.1002/2211-5463.13669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/23/2023] [Accepted: 06/30/2023] [Indexed: 07/05/2023] Open
Abstract
This study attempts to answer the question of whether mice with biallelic and monoallelic disruption of the St3gal5 (GM3 synthase) gene might benefit from GM1 replacement therapy. The GM3 produced by this sialyltransferase gives rise to downstream GD3 and the ganglio-series of gangliosides. The latter includes the a-series (GM1 + GD1a), which has proved most essential for neuron survival and function (especially GM1, for which GD1a provides a reserve pool). These biallelic mice serve as a model for children with this relatively rare autosomal recessive condition (ST3GAL5-/-) who suffer rapid neurological decline including motor loss, intellectual disability, visual and hearing loss, failure to thrive, and other severe conditions leading to an early death by 2-5 years of age without supportive care. Here, we studied both these mice, which serve as a model for the parents and close relatives of these children who are likely to suffer long-term disabilities due to partial deficiency of GM1, including Parkinson's disease (PD). We find that the movement and memory disorders manifested by both types of mice can be resolved with GM1 application. This suggests the potential therapeutic value of GM1 for disorders stemming from GM1 deficiency, including GM3 synthase deficiency and PD. It was noteworthy that the GM1 employed in these studies was synthetic rather than animal brain-derived, reaffirming the therapeutic efficacy of the former.
Collapse
Affiliation(s)
- Suman Chowdhury
- Department of Pharmacology, Physiology, and NeuroscienceRutgers, The State University of New JerseyNewarkNJUSA
| | - Ranjeet Kumar
- Department of Pharmacology, Physiology, and NeuroscienceRutgers, The State University of New JerseyNewarkNJUSA
| | - Evelyn Zepeda
- Department of Pharmacology, Physiology, and NeuroscienceRutgers, The State University of New JerseyNewarkNJUSA
| | | | - Robert Ledeen
- Department of Pharmacology, Physiology, and NeuroscienceRutgers, The State University of New JerseyNewarkNJUSA
| |
Collapse
|
3
|
Rudy N, Aoki K, Ananth A, Holloway L, Skinner C, Hurst A, Tiemeyer M, Steet R. Compound heterozygous variants within two conserved sialyltransferase motifs of ST3GAL5 cause GM3 synthase deficiency. JIMD Rep 2023; 64:138-145. [PMID: 36873089 PMCID: PMC9981410 DOI: 10.1002/jmd2.12353] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 12/03/2022] Open
Abstract
GM3 synthase deficiency (GM3SD) is caused by biallelic variants in ST3GAL5. The ganglioside GM3, enriched in neuronal tissues, is a component of lipid rafts and regulates numerous signaling pathways. Affected individuals with GM3SD exhibit global developmental delay, progressive microcephaly, and dyskinetic movements. Hearing loss and altered skin pigmentation are also common. Most of the reported variants in ST3GAL5 are found in motifs conserved across all sialyltransferases within the GT29 family of enzymes. These motifs include motif L and motif S which contain amino acids responsible for substrate binding. These loss-of-function variants cause greatly reduced biosynthesis of GM3 and gangliosides derived from GM3. Here we describe an affected female with typical GM3SD features bearing two novel variants that reside in the other two conserved sialyltransferase motifs (motif 3 and motif VS). These missense alterations occur in amino acid residues that are strictly invariant across the entire GT29 family of sialyltransferases. The functional significance of these variants was confirmed by mass spectrometric analysis of plasma glycolipids, demonstrating a striking loss of GM3 and accumulation of lactosylceramide and Gb3 in the patient. The glycolipid profile changes were accompanied by an increase in ceramide chain length on LacCer. No changes in receptor tyrosine phosphorylation were observed in patient-derived lymphoblasts, indicating that GM3 synthase loss-of-function in this cell type does not impact receptor tyrosine kinase activity. These findings demonstrate the high prevalence of loss-of-function ST3GAL5 variants within highly conserved sialyltransferase motifs in affected individuals with GM3SD.
Collapse
Affiliation(s)
- Natasha Rudy
- Department of GeneticsThe University of Alabama at BirminghamBirminghamAlabamaUSA
| | - Kazuhiro Aoki
- Complex Carbohydrate Research CenterUniversity of GeorgiaAthensGeorgiaUSA
| | - Amitha Ananth
- Department of GeneticsThe University of Alabama at BirminghamBirminghamAlabamaUSA
| | | | | | - Anna Hurst
- Department of GeneticsThe University of Alabama at BirminghamBirminghamAlabamaUSA
| | - Michael Tiemeyer
- Complex Carbohydrate Research CenterUniversity of GeorgiaAthensGeorgiaUSA
| | | |
Collapse
|
4
|
Watanabe S, Lei M, Nakagawa E, Takeshita E, Inamori KI, Shishido F, Sasaki M, Mitsuhashi S, Matsumoto N, Kimura Y, Iwasaki M, Takahashi Y, Mizusawa H, Migita O, Ohno I, Inokuchi JI. Neurological insights on two siblings with GM3 synthase deficiency due to novel compound heterozygous ST3GAL5 variants. Brain Dev 2023:S0387-7604(23)00002-5. [PMID: 36690566 DOI: 10.1016/j.braindev.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/24/2022] [Accepted: 01/10/2023] [Indexed: 01/22/2023]
Abstract
BACKGROUND ST3GAL5 encodes GM3 synthase (ST3 beta-galactoside alpha-2,3-sialyltransferase 5; ST3GAL5), which synthesizes GM3 by transferring sialic acid to lactosylceramide. GM3, a sialic acid-containing glycosphingolipid known as ganglioside, is a precursor to the biosynthesis of various more complex gangliosides that are active in the brain. Biallelic variants in ST3GAL5 cause GM3 synthase deficiency (GM3SD), a rare congenital disorder of glycosylation. GM3SD was first identified in the Amish population in 2004. CASE We report two siblings diagnosed with GM3SD due to novel compound heterozygous ST3GAL5 variants. The novel ST3GAL5 variants, detected by whole-exome sequencing in the patients, were confirmed to be pathogenic by GM3 synthase assay. The clinical courses of these patients, which began in infancy with irritability and growth failure, followed by developmental delay and hearing loss, were consistent with previous case reports of GM3SD. The older sibling underwent deep brain stimulation for severe involuntary movements at the age of 9 years. The younger sibling suffered from acute encephalopathy at the age of 9 months and subsequently developed refractory epilepsy. DISCUSSION Reports of GM3SD outside the Amish population are rare, and whole-exome sequencing may be required to diagnose GM3SD in non-Amish patients. Since an effective treatment for GM3SD has not yet been established, we might select deep brain stimulation as a symptomatic treatment for involuntary movements in GM3SD.
Collapse
|
5
|
Abstract
GM3 synthase (GM3S) is a sialyltransferase that transfers sialic acid from CMP-sialic acid to lactosylceramide. This reaction results in formation of ganglioside GM3 and is essential for biosynthesis of its downstream derivatives, which include a- and b-series gangliosides. Here, we describe a method for GM3S enzymatic assay using fluorescence-labeled alkyl lactoside as acceptor substrate, followed by HPLC for separation of enzymatic product. The method allows quantitative assay of GM3S sialyltransferase activity in cultured cells and mouse brain tissues.
Collapse
Affiliation(s)
- Kei-Ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan.
| | - Takahiro Nitta
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Fumi Shishido
- Center for Medical Education, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Soichiro Watanabe
- Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan
| | - Isao Ohno
- Center for Medical Education, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Jin-Ichi Inokuchi
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
- Forefront Research Center, Graduate School of Sciences, Osaka University, Osaka, Japan
| |
Collapse
|
6
|
Ledeen R, Chowdhury S. Gangliosides in Neurodegenerative Diseases. Advances in Neurobiology 2023. [DOI: 10.1007/978-3-031-12390-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
7
|
Bharathi SS, Zhang BB, Paul E, Zhang Y, Schmidt AV, Fowler B, Wu Y, Tiemeyer M, Inamori KI, Inokuchi JI, Goetzman ES. GM3 synthase deficiency increases brain glucose metabolism in mice. Mol Genet Metab 2022; 137:342-348. [PMID: 36335793 PMCID: PMC11061803 DOI: 10.1016/j.ymgme.2022.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/24/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022]
Abstract
GM3 synthase (GM3S) deficiency is a rare neurodevelopmental disorder caused by an inability to synthesize gangliosides, for which there is currently no treatment. Gangliosides are brain-enriched, plasma membrane glycosphingolipids with poorly understood biological functions related to cell adhesion, growth, and receptor-mediated signal transduction. Here, we investigated the effects of GM3S deficiency on metabolism and mitochondrial function in a mouse model. By indirect calorimetry, GM3S knockout mice exhibited increased whole-body respiration and an increased reliance upon carbohydrate as an energy source. 18F-FDG PET confirmed higher brain glucose uptake in knockout mice, and GM3S deficient N41 neuronal cells showed higher glucose utilization in vitro. Brain mitochondria from knockout mice respired at a higher rate on Complex I substrates including pyruvate. This appeared to be due to higher expression of pyruvate dehydrogenase (PDH) and lower phosphorylation of PDH, which would favor pyruvate entry into the mitochondrial TCA cycle. Finally, it was observed that blocking glucose metabolism with the glycolysis inhibitor 2-deoxyglucose reduced seizure intensity in GM3S knockout mice following administration of kainate. In conclusion, GM3S deficiency may be associated with a hypermetabolic phenotype that could promote seizure activity.
Collapse
Affiliation(s)
- Sivakama S Bharathi
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Bob B Zhang
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Eli Paul
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Yuxun Zhang
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Alexandra V Schmidt
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Benjamin Fowler
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Yijen Wu
- Department of Developmental Biology, University of Pittsburgh, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, United States of America
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States of America
| | - Kei-Ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi 981-8558, Japan
| | - Jin-Ichi Inokuchi
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi 981-8558, Japan
| | - Eric S Goetzman
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America..
| |
Collapse
|
8
|
Inamori KI, Inokuchi JI. Ganglioside GM3 Synthase Deficiency in Mouse Models and Human Patients. Int J Mol Sci 2022; 23:ijms23105368. [PMID: 35628171 PMCID: PMC9141422 DOI: 10.3390/ijms23105368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/08/2022] [Accepted: 05/09/2022] [Indexed: 12/22/2022] Open
Abstract
Gangliosides (glycosphingolipids containing one or more sialic acids) are highly expressed in neural tissues in vertebrates, and four species (GM1a, GD1a, GD1b, GT1b) are predominant in mammalian brains. GM3 is the precursor of each of these four species and is the major ganglioside in many nonneural tissues. GM3 synthase (GM3S), encoded by ST3GAL5 gene in humans, is a sialyltransferase responsible for synthesis of GM3 from its precursor, lactosylceramide. ST3GAL5 mutations cause an autosomal recessive form of severe infantile-onset neurological disease characterized by progressive microcephaly, intellectual disability, dyskinetic movements, blindness, deafness, intractable seizures, and pigment changes. Some of these clinical features are consistently present in patients with ST3GAL5 mutations, whereas others have variable expression. GM3S knockout (KO) mice have deafness and enhanced insulin sensitivity, but otherwise do not display the above-described neurological defects reported in ST3GAL5 patients. The authors present an overview of physiological functions and pathological aspects of gangliosides based on findings from studies of GM3S KO mice and discuss differential phenotypes of GM3S KO mice versus human GM3S-deficiency patients.
Collapse
Affiliation(s)
- Kei-ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Miyagi, Japan
- Correspondence: (K.-i.I.); (J.-i.I.)
| | - Jin-ichi Inokuchi
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Miyagi, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, Toyonaka 560-0043, Osaka, Japan
- Correspondence: (K.-i.I.); (J.-i.I.)
| |
Collapse
|