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Aureli M, Mauri L, Carsana EV, Dobi D, Breviario S, Lunghi G, Sonnino S. Gangliosides and Cell Surface Ganglioside Metabolic Enzymes in the Nervous System. ADVANCES IN NEUROBIOLOGY 2023; 29:305-332. [DOI: 10.1007/978-3-031-12390-0_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Can M, Sengül T, Demir SA, İnci OK, Basırlı H, Seyrantepe V. Analysis of Brain Lipids in the Early-Onset Tay–Sachs Disease Mouse Model With the Combined Deficiency of β-Hexosaminidase A and Neuraminidase 3. Front Mol Biosci 2022; 9:892248. [PMID: 36003081 PMCID: PMC9393265 DOI: 10.3389/fmolb.2022.892248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction: Tay–Sachs disease is an autosomal recessively inherited lysosomal storage disease that results from loss-of-function mutations in the HEXA gene coding β-hexosaminidase A. HEXA gene deficiency affects the central nervous system owing to GM2 ganglioside accumulation in lysosomes resulting in progressive neurodegeneration in patients. We recently generated a novel mice model with a combined deficiency of β-hexosaminidase A and neuraminidase 3 (Hexa−/−Neu3−/−) that mimics both the neuropathological and clinical abnormalities of early-onset Tay–Sachs disease. Here, we aimed to explore the secondary accumulation of lipids in the brain of Hexa−/−Neu3−/− mice.Materials and Methods: In the cortex and hippocampus of five-month-old WT, Hexa−/−, Neu3−/−, and Hexa−/−Neu3−/− mice, lipid levels belonging to glycerolipids, glycerophospholipids, and sterol lipids were evaluated using a shotgun lipidomics approach. The levels of myelin were also assessed by luxol fast blue staining and immunohistochemistry using antibodies against myelin basic protein. We further examined glycoconjugate and cholesterol levels by periodic acid–Schiff and filipin staining, respectively. Toluidine blue staining was also performed to display axonal degeneration.Results: Among glycerophospholipids, we demonstrated elevated levels of phosphatidylcholine-ether and lysophosphatidylcholine while decreased levels of phosphatidylcholine and phosphatidylserine in both cortex and hippocampus of Hexa−/−Neu3−/− mice. In the glycerolipid class, we showed an alleviated level of sphingomyelin in both cortex and hippocampus, but the higher levels of diacylglycerol and triacylglycerol were detected in only the hippocampus of Hexa−/−Neu3−/− mice. The lower level of sterol was also detected in the cortex of Hexa−/−Neu3−/− mice but not in the hippocampus.Histochemical studies showed a decrease in the myelin level and axonal degeneration indicating neuronal pathology in the brain of Hexa−/−Neu3−/− mice. Although glycoconjugate accumulation was evident both in the cortex and hippocampus, we did not detect any changes in the level of cholesterol.Conclusion: Our results indicate that alterations in lipid metabolism and neuropathology, such as demyelination and axonal degeneration, might be related to the dysfunctionality of lipid-related cellular pathways like autophagy. Understanding of brain-specific lipid alterations contributes to evaluating the effectiveness of treatments in Hexa−/−Neu3−/− mice in future studies.
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Affiliation(s)
- Melike Can
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Izmir, Turkey
| | - Tugce Sengül
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Izmir, Turkey
| | | | - Orhan K. İnci
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Izmir, Turkey
| | - Hande Basırlı
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Izmir, Turkey
| | - Volkan Seyrantepe
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Izmir, Turkey
- Izmir Institute of Technology, IYTEDEHAM, Izmir, Turkey
- *Correspondence: Volkan Seyrantepe,
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González-Cuesta M, Herrera-González I, García-Moreno MI, Ashmus RA, Vocadlo DJ, García Fernández JM, Nanba E, Higaki K, Ortiz Mellet C. sp 2-Iminosugars targeting human lysosomal β-hexosaminidase as pharmacological chaperone candidates for late-onset Tay-Sachs disease. J Enzyme Inhib Med Chem 2022; 37:1364-1374. [PMID: 35575117 PMCID: PMC9126592 DOI: 10.1080/14756366.2022.2073444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The late-onset form of Tay-Sachs disease displays when the activity levels of human β-hexosaminidase A (HexA) fall below 10% of normal, due to mutations that destabilise the native folded form of the enzyme and impair its trafficking to the lysosome. Competitive inhibitors of HexA can rescue disease-causative mutant HexA, bearing potential as pharmacological chaperones, but often also inhibit the enzyme O-glucosaminidase (GlcNAcase; OGA), a serious drawback for translation into the clinic. We have designed sp2-iminosugar glycomimetics related to GalNAc that feature a neutral piperidine-derived thiourea or a basic piperidine-thiazolidine bicyclic core and behave as selective nanomolar competitive inhibitors of human Hex A at pH 7 with a ten-fold lower inhibitory potency at pH 5, a good indication for pharmacological chaperoning. They increased the levels of lysosomal HexA activity in Tay-Sachs patient fibroblasts having the G269S mutation, the highest prevalent in late-onset Tay-Sachs disease.
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Affiliation(s)
- Manuel González-Cuesta
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Sevilla, Spain
| | - Irene Herrera-González
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Sevilla, Spain
| | - M Isabel García-Moreno
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Sevilla, Spain
| | - Roger A Ashmus
- Department of Chemistry and Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, Canada
| | - David J Vocadlo
- Department of Chemistry and Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, Canada
| | - José M García Fernández
- Instituto de Investigaciones Químicas (IIQ), Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Sevilla, Sevilla, Spain
| | - Eiji Nanba
- Organization for Research Initiative and Promotion, Tottori University, Yonago, Japan
| | - Katsumi Higaki
- Organization for Research Initiative and Promotion, Tottori University, Yonago, Japan
| | - Carmen Ortiz Mellet
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Sevilla, Spain
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Ali AH, Wei W, Wang X. A review of milk gangliosides: Occurrence, biosynthesis, identification, and nutritional and functional significance. INT J DAIRY TECHNOL 2021. [DOI: 10.1111/1471-0307.12816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Abdelmoneim H Ali
- Department of Food Science Faculty of Agriculture Zagazig University Zagazig 44511 Egypt
- International Joint Research Laboratory for Lipid Nutrition and Safety Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province School of Food Science and Technology Jiangnan University Wuxi 214122 China
| | - Wei Wei
- International Joint Research Laboratory for Lipid Nutrition and Safety Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province School of Food Science and Technology Jiangnan University Wuxi 214122 China
| | - Xingguo Wang
- International Joint Research Laboratory for Lipid Nutrition and Safety Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province School of Food Science and Technology Jiangnan University Wuxi 214122 China
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Integrated Computational Analysis Highlights unique miRNA Signatures in the Subventricular Zone and Striatum of GM2 Gangliosidosis Animal Models. Int J Mol Sci 2019; 20:ijms20133179. [PMID: 31261761 PMCID: PMC6651736 DOI: 10.3390/ijms20133179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/24/2019] [Accepted: 06/27/2019] [Indexed: 12/12/2022] Open
Abstract
This work explores for the first time the potential contribution of microRNAs (miRNAs) to the pathophysiology of the GM2 gangliosidosis, a group of Lysosomal Storage Diseases. In spite of the genetic origin of GM2 gangliosidosis, the cascade of events leading from the gene/protein defects to the cell dysfunction and death is not fully elucidated. At present, there is no cure for patients. Taking advantage of the animal models of two forms of GM2 gangliosidosis, Tay-Sachs (TSD) and Sandhoff (SD) diseases, we performed a microRNA screening in the brain subventricular zone (SVZ) and striatum (STR), which feature the neurogenesis and neurodegeneration states, respectively, in adult mutant mice. We found abnormal expression of a panel of miRNAs involved in lipid metabolism, CNS development and homeostasis, and neuropathological processes, highlighting region- and disease-specific profiles of miRNA expression. Moreover, by using a computational analysis approach, we identified a unique disease- (SD or TSD) and brain region-specific (SVZ vs. STR) miRNAs signatures of predicted networks potentially related to the pathogenesis of the diseases. These results may contribute to the understanding of GM2 gangliosidosis pathophysiology, with the aim of developing effective treatments.
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Kato A, Nakagome I, Nakagawa S, Kinami K, Adachi I, Jenkinson SF, Désiré J, Blériot Y, Nash RJ, Fleet GWJ, Hirono S. In silico analyses of essential interactions of iminosugars with the Hex A active site and evaluation of their pharmacological chaperone effects for Tay-Sachs disease. Org Biomol Chem 2018; 15:9297-9304. [PMID: 28959811 DOI: 10.1039/c7ob02281f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The affinity of a series of iminosugar-based inhibitors exhibiting various ring sizes toward Hex A and their essential interactions with the enzyme active site were investigated. All the Hex A-inhibiting iminosugars tested formed hydrogen bonds with Arg178, Asp322, Tyr421 and Glu462 and had the favorable cation-π interaction with Trp460. Among them, DMDP amide (6) proved to be the most potent competitive inhibitor with a Ki value of 0.041 μM. We analyzed the dynamic properties of both DMDP amide (6) and DNJNAc (1) in aqueous solution using molecular dynamics (MD) calculations; the distance of the interaction between Asp322 and 3-OH and Glu323 and 6-OH was important for stable interactions with Hex A, reducing fluctuations in the plasticity of the active site. DMDP amide (6) dose-dependently increased intracellular Hex A activity in the G269S mutant cells and restored Hex A activity up to approximately 43% of the wild type level; this effect clearly exceeded the border line treatment for Tay-Sachs disease, which is regarded as 10-15% of the wild type level. This is a significantly greater effect than that of pyrimethamine, which is currently in Phase 2 clinical trials. DMDP amide (6), therefore, represents a new promising pharmacological chaperone candidate for the treatment of Tay-Sachs disease.
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Affiliation(s)
- Atsushi Kato
- Department of Hospital Pharmacy, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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Cachón-González MB, Zaccariotto E, Cox TM. Genetics and Therapies for GM2 Gangliosidosis. Curr Gene Ther 2018; 18:68-89. [PMID: 29618308 PMCID: PMC6040173 DOI: 10.2174/1566523218666180404162622] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 01/10/2018] [Accepted: 01/27/2018] [Indexed: 12/30/2022]
Abstract
Tay-Sachs disease, caused by impaired β-N-acetylhexosaminidase activity, was the first GM2 gangliosidosis to be studied and one of the most severe and earliest lysosomal diseases to be described. The condition, associated with the pathological build-up of GM2 ganglioside, has acquired almost iconic status and serves as a paradigm in the study of lysosomal storage diseases. Inherited as a classical autosomal recessive disorder, this global disease of the nervous system induces developmental arrest with regression of attained milestones; neurodegeneration progresses rapidly to cause premature death in young children. There is no effective treatment beyond palliative care, and while the genetic basis of GM2 gangliosidosis is well established, the molecular and cellular events, from diseasecausing mutations and glycosphingolipid storage to disease manifestations, remain to be fully delineated. Several therapeutic approaches have been attempted in patients, including enzymatic augmentation, bone marrow transplantation, enzyme enhancement, and substrate reduction therapy. Hitherto, none of these stratagems has materially altered the course of the disease. Authentic animal models of GM2 gangliodidosis have facilitated in-depth evaluation of innovative applications such as gene transfer, which in contrast to other interventions, shows great promise. This review outlines current knowledge pertaining the pathobiology as well as potential innovative treatments for the GM2 gangliosidoses.
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Affiliation(s)
| | - Eva Zaccariotto
- Department of Medicine, University of Cambridge, Cambridge, UK
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Dersh D, Iwamoto Y, Argon Y. Tay-Sachs disease mutations in HEXA target the α chain of hexosaminidase A to endoplasmic reticulum-associated degradation. Mol Biol Cell 2016; 27:3813-3827. [PMID: 27682588 PMCID: PMC5170605 DOI: 10.1091/mbc.e16-01-0012] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 09/15/2016] [Accepted: 09/22/2016] [Indexed: 12/29/2022] Open
Abstract
In Tay–Sachs disease, mutations in HEXA can lead to aberrant α subunits of the HexA enzyme. Two such mutants have folding defects and are cleared by endoplasmic reticulum-associated degradation. Toward the pursuit of therapeutic treatments, it was found that manipulating endoplasmic reticulum quality control can impair mutant α degradation and improve cellular Hex activity. Loss of function of the enzyme β-hexosaminidase A (HexA) causes the lysosomal storage disorder Tay–Sachs disease (TSD). It has been proposed that mutations in the α chain of HexA can impair folding, enzyme assembly, and/or trafficking, yet there is surprisingly little known about the mechanisms of these potential routes of pathogenesis. We therefore investigated the biosynthesis and trafficking of TSD-associated HexA α mutants, seeking to identify relevant cellular quality control mechanisms. The α mutants E482K and G269S are defective in enzymatic activity, unprocessed by lysosomal proteases, and exhibit altered folding pathways compared with wild-type α. E482K is more severely misfolded than G269S, as observed by its aggregation and inability to associate with the HexA β chain. Importantly, both mutants are retrotranslocated from the endoplasmic reticulum (ER) to the cytosol and are degraded by the proteasome, indicating that they are cleared via ER-associated degradation (ERAD). Leveraging these discoveries, we observed that manipulating the cellular folding environment or ERAD pathways can alter the kinetics of mutant α degradation. Additionally, growth of patient fibroblasts at a permissive temperature or with chemical chaperones increases cellular Hex activity by improving mutant α folding. Therefore modulation of the ER quality control systems may be a potential therapeutic route for improving some forms of TSD.
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Affiliation(s)
- Devin Dersh
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA 19104
| | - Yuichiro Iwamoto
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA 19104
| | - Yair Argon
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA 19104
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Hattie M, Cekic N, Debowski AW, Vocadlo DJ, Stubbs KA. Modifying the phenyl group of PUGNAc: reactivity tuning to deliver selective inhibitors for N-acetyl-d-glucosaminidases. Org Biomol Chem 2016; 14:3193-7. [DOI: 10.1039/c6ob00297h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of analogues of the potentN-acetylhexosamindase inhibitor PUGNAc are described and were found to vary in both potency and selectivity against a set of biologically importantN-acetyl-d-glucosaminidases.
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Affiliation(s)
- Mitchell Hattie
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
| | - Nevena Cekic
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
| | - Aleksandra W. Debowski
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
- School of Pathology and Laboratory Medicine
| | - David J. Vocadlo
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
- Department of Molecular Biology and Biochemistry
| | - Keith A. Stubbs
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
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Timur ZK, Akyildiz Demir S, Marsching C, Sandhoff R, Seyrantepe V. Neuraminidase-1 contributes significantly to the degradation of neuronal B-series gangliosides but not to the bypass of the catabolic block in Tay-Sachs mouse models. Mol Genet Metab Rep 2015; 4:72-82. [PMID: 26937414 PMCID: PMC4750590 DOI: 10.1016/j.ymgmr.2015.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/23/2015] [Accepted: 07/23/2015] [Indexed: 11/17/2022] Open
Affiliation(s)
- Z K Timur
- Izmir Institute of Technology, Department of Molecular Biology and Genetics, Izmir, Turkey
| | - S Akyildiz Demir
- Izmir Institute of Technology, Department of Molecular Biology and Genetics, Izmir, Turkey
| | - C Marsching
- Lipid Biochemistry Lab, Cancer Research Center, Heidelberg, Germany
| | - R Sandhoff
- Lipid Biochemistry Lab, Cancer Research Center, Heidelberg, Germany
| | - V Seyrantepe
- Izmir Institute of Technology, Department of Molecular Biology and Genetics, Izmir, Turkey
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Ariga T. Pathogenic role of ganglioside metabolism in neurodegenerative diseases. J Neurosci Res 2014; 92:1227-42. [PMID: 24903509 DOI: 10.1002/jnr.23411] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 04/09/2014] [Accepted: 04/09/2014] [Indexed: 12/13/2022]
Abstract
Ganglioside metabolism is altered in several neurodegenerative diseases, and this may participate in several events related to the pathogenesis of these diseases. Most changes occur in specific areas of the brain and their distinct membrane microdomains or lipid rafts. Antiganglioside antibodies may be involved in dysfunction of the blood-brain barrier and disease progression in these diseases. In lipid rafts, interactions of glycosphingolipids, including ganglioside, with proteins may be responsible for the misfolding events that cause the fibril and/or aggregate processing of disease-specific proteins, such as α-synuclein, in Parkinson's disease, huntingtin protein in Huntington's disease, and copper-zinc superoxide dismutase in amyotrophic lateral sclerosis. Targeting ganglioside metabolism may represent an underexploited opportunity to design novel therapeutic strategies for neurodegeneration in these diseases.
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Affiliation(s)
- Toshio Ariga
- Institute of Molecular Medicine and Genetics, Institute of Neuroscience, Medical College of Georgia, Georgia Regents University, Augusta, Georgia
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Gangliosides and Cell Surface Ganglioside Glycohydrolases in the Nervous System. ADVANCES IN NEUROBIOLOGY 2014; 9:223-44. [DOI: 10.1007/978-1-4939-1154-7_10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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13
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Aureli M, Samarani M, Loberto N, Bassi R, Murdica V, Prioni S, Prinetti A, Sonnino S. The Glycosphingolipid Hydrolases in the Central Nervous System. Mol Neurobiol 2013; 50:76-87. [DOI: 10.1007/s12035-013-8592-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 11/08/2013] [Indexed: 12/27/2022]
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Lew RM, Proos AL, Burnett L, Delatycki M, Bankier A, Fietz MJ. Tay Sachs disease in Australia: reduced disease incidence despite stable carrier frequency in Australian Jews. Med J Aust 2013; 197:652-4. [PMID: 23230938 DOI: 10.5694/mja12.11010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 10/15/2012] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To evaluate the outcomes of preconception screening of Jewish Australians for Tay Sachs disease (TSD) carrier status on Jewish TSD-affected births. DESIGN, PARTICIPANTS AND SETTING Epidemiological observational study involving a complete retrospective audit of infantile and intermediate TSD cases diagnosed in Sydney and Melbourne between 1 January 1995 and 31 December 2011 (Royal Children's Hospital Melbourne; Pacific Laboratory Medicine Services, Pathology North, NSW Health Pathology, Sydney; Victorian Clinical Genetics Services, Melbourne; and SA Pathology, Adelaide), and carrier frequency among Jewish high school students attending schools participating in TSD screening programs over the same period. MAIN OUTCOME MEASURES Jewish TSD carrier frequency; and expected versus observed Jewish TSD-affected births. RESULTS The 2006 Census indicated that most of the total 88,826 Jewish Australians live in Melbourne (46%) and Sydney (40%). The 7,756 Jewish high school students screened for TSD in Sydney and Melbourne during the study period had a carrier frequency of one in 31 (3.26%; 95% CI, 2.89%-3.68%).The estimated expected number of TSD-affected births in Melbourne and Sydney in 1995-2011 was 4.1 for Jewish births and 7.4 for other births (a ratio of Jewish to non-Jewish births of 1:2). The actual number was 12 (four in Sydney and eight in Melbourne), of which two were Jewish (a ratio of Jewish to non-Jewish births of 1:5). This finding of fewer than expected Jewish TSD cases coincided with a period during which screening programs were operating. There have been no Jewish TSD-affected children born to parents who were screened previously. CONCLUSION Community education, appreciation of autosomal recessive inheritance and genetic carrier screening before pregnancy are the likely factors in our finding of fewer than expected Jewish babies with TSD. Ongoing outcome monitoring must continue.
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Affiliation(s)
- Raelia M Lew
- Department of Obstetrics, Gynaecology and Neonatology, University of Sydney, and Pacific Laboratory Medicine Services, Pathology North, NSW Health Pathology, Royal North Shore Hospital, Sydney, NSW, Australia.
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Sumida T, Stubbs KA, Ito M, Yokoyama S. Gaining insight into the inhibition of glycoside hydrolase family 20 exo-β-N-acetylhexosaminidases using a structural approach. Org Biomol Chem 2012; 10:2607-12. [PMID: 22367352 DOI: 10.1039/c2ob06636j] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
One useful methodology that has been used to give insight into how chemically synthesized inhibitors bind to enzymes and the reasons underlying their potency is crystallographic studies of inhibitor-enzyme complexes. Presented here is the X-ray structural analysis of a representative family 20 exo-β-N-acetylhexosaminidase in complex with various known classes of inhibitor of these types of enzymes, which highlights how different inhibitor classes can inhibit the same enzyme. This study will aid in the future development of inhibitors of not only exo-β-N-acetylhexosaminidases but also other types of glycoside hydrolases.
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Affiliation(s)
- Tomomi Sumida
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
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Invertebrate models of lysosomal storage disease: what have we learned so far? INVERTEBRATE NEUROSCIENCE 2011; 11:59-71. [PMID: 22038288 DOI: 10.1007/s10158-011-0125-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 10/08/2011] [Indexed: 01/17/2023]
Abstract
The lysosomal storage diseases (LSDs) collectively account for death in 1 in 8,000 children. Although some forms are treatable, they are essentially incurable and usually are lethal in the first decade of life. The most intractable forms of LSD are those with neuronal involvement. In an effort to identify the pathological signaling driving pathology in the LSDs, invertebrate models have been developed. In this review, we outline our current understanding of LSDs and recent findings using invertebrate models. We outline strategies and pitfalls for the development of such models. Available models of LSD in Drosophila and Caenorhabditis elegans are uncovering roles for LSD-related proteins with previously unknown function using both gain-of-function and loss-of-function strategies. These models of LSD in Drosophila and C. elegans have identified potential pathogenic signaling cascades that are proving critical to our understanding of these lethal diseases.
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Tay-Sachs disease preconception screening in Australia: self-knowledge of being an Ashkenazi Jew predicts carrier state better than does ancestral origin, although there is an increased risk for c.1421 + 1G > C mutation in individuals with South African heritage. J Community Genet 2011; 2:201-9. [PMID: 22109873 DOI: 10.1007/s12687-011-0057-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 06/30/2011] [Indexed: 10/18/2022] Open
Abstract
The Australasian Community Genetics Program provided a preconception screening for Tay-Sachs disease (TSD) to 4,105 Jewish high school students in Sydney and Melbourne over the 12-year period 1995-2007. By correlating the frequencies of mutant HEXA, MIM *606869 (gene map locus 15q23-q24) alleles with subjects' nominated ethnicity (Ashkenazi/Sephardi/Mixed) and grandparental birthplaces, we established that Ashkenazi ethnicity is a better predictor of TSD carrier status than grandparental ancestral origins. Screening self-identified Ashkenazi subjects detected 95% of TSD carriers (carrier frequency 1:25). Having mixed Ashkenazi and non-Ashkenazi heritage reduced the carrier frequency (1:97). South African heritage conveyed a fourfold risk of c.1421 + 1G > C mutation compared with other AJ subjects (odds ratio (OR), 4.19; 95% confidence interval (CI), 1.83-9.62, p = 0.001), but this was the only specific case of ancestral origin improving diagnostic sensitivity over that based on determining Ashkenazi ethnicity. Carriers of c.1278insTATC mutations were more likely to have heritage from Western Europe (OR, 1.65 (95% CI, 1.04-2.60), p = 0.032) and South Eastern Europe (OR, 1.77 (95% CI, 1.14-2.73), p = 0.010). However, heritage from specific European countries investigated did not significantly alter the overall odds of TSD carrier status.
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Macauley MS, Shan X, Yuzwa SA, Gloster TM, Vocadlo DJ. Elevation of Global O-GlcNAc in rodents using a selective O-GlcNAcase inhibitor does not cause insulin resistance or perturb glucohomeostasis. ACTA ACUST UNITED AC 2011; 17:949-58. [PMID: 20851344 PMCID: PMC2954292 DOI: 10.1016/j.chembiol.2010.07.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 07/08/2010] [Accepted: 07/12/2010] [Indexed: 01/05/2023]
Abstract
The O-GlcNAc modification is proposed to be a nutrient sensor with studies suggesting that global increases in O-GlcNAc levels cause insulin resistance and impaired glucohomeostasis. We address this hypothesis by using a potent and selective inhibitor of O-GlcNAcase, known as NButGT, in a series of in vivo studies. Treatment of rats and mice with NButGT, for various time regimens and doses, dramatically increases O-GlcNAc levels throughout all tissues but does not perturb insulin sensitivity or alter glucohomeostasis. NButGT also does not affect the severity or onset of insulin resistance induced by a high-fat diet. These results suggest that pharmacological increases in global O-GlcNAc levels do not cause insulin resistance nor do they appear to disrupt glucohomeostasis. Therefore, the protective benefits of elevated O-GlcNAc levels may be achieved without deleteriously affecting glucohomeostasis.
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Goddard-Borger ED, Stubbs KA. An improved route to PUGNAc and its galacto-configured congener. J Org Chem 2010; 75:3931-4. [PMID: 20443616 DOI: 10.1021/jo100614b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An efficient, scalable, and reliable synthesis of PUGNAc and its galacto-configured congener is reported.
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Affiliation(s)
- Ethan D Goddard-Borger
- Chemistry M313, School of Biomedical, Biomolecular and Chemical Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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Macauley MS, Vocadlo DJ. Increasing O-GlcNAc levels: An overview of small-molecule inhibitors of O-GlcNAcase. Biochim Biophys Acta Gen Subj 2009; 1800:107-21. [PMID: 19664691 DOI: 10.1016/j.bbagen.2009.07.028] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Revised: 07/17/2009] [Accepted: 07/28/2009] [Indexed: 11/25/2022]
Abstract
The O-GlcNAc modification is found on many nucleocytoplasmic proteins. The dynamic nature of O-GlcNAc, which in some ways is reminiscent of phosphorylation, has enabled investigators to modulate the stoichiometry of O-GlcNAc on proteins in order to study its function. Although several genetic and pharmacological methods for manipulating O-GlcNAc levels have been described, one of the most direct approaches of increasing global O-GlcNAc levels is by using small-molecule inhibitors of O-GlcNAcase (OGA). As the interest in increasing O-GlcNAc levels has grown, so too has the number of OGA inhibitors. This review provides an overview of the available methods of increasing O-GlcNAc levels, with a special emphasis on inhibition of OGA by small molecules. Known inhibitors of OGA are discussed with particular attention on those most suitable for cell-based biological studies. Several examples in which OGA inhibitors have been used to study the functional role of the O-GlcNAc modification in biological systems are discussed, highlighting the pros and cons of different inhibitors.
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Affiliation(s)
- Matthew S Macauley
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada
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Martinez-Fleites C, He Y, Davies GJ. Structural analyses of enzymes involved in the O-GlcNAc modification. Biochim Biophys Acta Gen Subj 2009; 1800:122-33. [PMID: 19647042 DOI: 10.1016/j.bbagen.2009.07.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2009] [Revised: 07/13/2009] [Accepted: 07/18/2009] [Indexed: 12/22/2022]
Abstract
In order to study the O-GlcNAc modification in vivo, it is evident that a range of specific small molecule inhibitors would be a valuable asset. One strategy for the design of such compounds would be to utilise 3-D structural information in tandem with knowledge of catalytic mechanism. The last few years has seen major breakthroughs in our understanding of the 3-D structure of the enzymes involved in the O-GlcNAc modification notably from the study of the tetratricopeptide repeat (TPR) domain of the human O-GlcNAc transferase, of the bacterial homologs of the O-GlcNAc hydrolase and more latterly bacterial homologs of the O-GlcNAc transferase itself. Of particular note are the bacterial O-GlcNAc hydrolase homologs that provide near identical active centres to the human enzyme. These have informed the design and/or subsequent analysis of inhibitors of this enzyme which have found great use in the chemical dissection of the O-GlcNAc in vivo, as described by Macauley and Vocadlo elsewhere in this issue.
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Affiliation(s)
- Carlos Martinez-Fleites
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York, YO10 5YW, UK
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Stubbs K, Macauley M, Vocadlo D. A Selective Inhibitor Gal-PUGNAc of Human Lysosomal β-Hexosaminidases Modulates Levels of the Ganglioside GM2 in Neuroblastoma Cells. Angew Chem Int Ed Engl 2009; 48:1300-3. [DOI: 10.1002/anie.200804583] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Stubbs K, Macauley M, Vocadlo D. A Selective Inhibitor Gal-PUGNAc of Human Lysosomal β-Hexosaminidases Modulates Levels of the Ganglioside GM2 in Neuroblastoma Cells. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200804583] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Stubbs KA, Zhang N, Vocadlo DJ. A divergent synthesis of 2-acyl derivatives of PUGNAc yields selective inhibitors of O-GlcNAcase. Org Biomol Chem 2006; 4:839-45. [PMID: 16493467 DOI: 10.1039/b516273d] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A divergent route facilitating the rapid synthesis of a series of O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino N-phenylcarbamate (PUGNAc)-based inhibitors, bearing different N-acyl groups has been developed. All compounds of this series are inhibitors of both human O-GlcNAcase and human beta-hexosaminidase, yet some effectively exploit differences between the active site architectures of these two human enzymes which render them selective for O-GlcNAcase. Such inhibitors may be valuable tools in dissecting the role of the O-GlcNAc post-translational modification at the cellular and organismal level since these compounds may have different pharmacokinetic properties when compared to other inhibitors of beta-N-acetyl-glucosaminidases.
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Affiliation(s)
- Keith A Stubbs
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6
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25
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Macauley MS, Whitworth GE, Debowski AW, Chin D, Vocadlo DJ. O-GlcNAcase uses substrate-assisted catalysis: kinetic analysis and development of highly selective mechanism-inspired inhibitors. J Biol Chem 2005; 280:25313-22. [PMID: 15795231 DOI: 10.1074/jbc.m413819200] [Citation(s) in RCA: 297] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The post-translational modification of serine and threonine residues of nucleocytoplasmic proteins with 2-acetamido-2-deoxy-d-glucopyranose (GlcNAc) is a reversible process implicated in multiple cellular processes. The enzyme O-GlcNAcase catalyzes the cleavage of beta-O-linked GlcNAc (O-GlcNAc) from modified proteins and is a member of the family 84 glycoside hydrolases. The family 20 beta-hexosaminidases bear no apparent sequence similarity yet are functionally related to O-GlcNAcase because both enzymes cleave terminal GlcNAc residues from glycoconjugates. Lysosomal beta-hexosaminidase is known to use substrate-assisted catalysis involving the 2-acetamido group of the substrate; however, the catalytic mechanism of human O-GlcNAcase is unknown. By using a series of 4-methylumbelliferyl 2-deoxy-2-N-fluoroacetyl-beta-D-glucopyranoside substrates, Taft-like linear free energy analyses of these enzymes indicates that O-GlcNAcase uses a catalytic mechanism involving anchimeric assistance. Consistent with this proposal, 1,2-dideoxy-2'-methyl-alpha-D-glucopyranoso-[2,1-d]-Delta2'-thiazoline, an inhibitor that mimics the oxazoline intermediate proposed in the catalytic mechanism of family 20 glycoside hydrolases, is shown to act as a potent competitive inhibitor of both O-GlcNAcase (K(I) = 0.070 microm) and beta-hexosaminidase (K = 0.070 microm). A series of 1,2-dideoxy-2'-methyl-alpha-D-glucopyranoso-[2,1-d]-Delta2'-thiazoline analogues were prepared, and one inhibitor demonstrated a remarkable 1500-fold selectivity for O-GlcNAcase (K(I) = 0.230 microm) over beta-hexosaminidase (K(I) = 340 microm). These inhibitors are cell permeable and modulate the activity of O-GlcNAcase in tissue culture. Because both enzymes have vital roles in organismal health, these potent and selective inhibitors of O-GlcNAcase should prove useful in studying the role of this enzyme at the organismal level without generating a complex chemical phenotype stemming from concomitant inhibition of beta-hexosaminidase.
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Affiliation(s)
- Matthew S Macauley
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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Sanchez JA, Pierce KE, Rice JE, Wangh LJ. Linear-after-the-exponential (LATE)-PCR: an advanced method of asymmetric PCR and its uses in quantitative real-time analysis. Proc Natl Acad Sci U S A 2004; 101:1933-8. [PMID: 14769930 PMCID: PMC357030 DOI: 10.1073/pnas.0305476101] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Conventional asymmetric PCR is inefficient and difficult to optimize because limiting the concentration of one primer lowers its melting temperature below the reaction annealing temperature. Linear-After-The-Exponential (LATE)-PCR describes a new paradigm for primer design that renders assays as efficient as symmetric PCR assays, regardless of primer ratio. LATE-PCR generates single-stranded products with predictable kinetics for many cycles beyond the exponential phase. LATE-PCR also introduces new probe design criteria that uncouple hybridization probe detection from primer annealing and extension, increase probe reliability, improve allele discrimination, and increase signal strength by 80-250% relative to symmetric PCR. These improvements in PCR are particularly useful for real-time quantitative analysis of target numbers in small samples. LATE-PCR is adaptable to high throughput applications in fields such as clinical diagnostics, biodefense, forensics, and DNA sequencing. We showcase LATE-PCR via amplification of the cystic fibrosis CFDelta508 allele and the Tay-Sachs disease TSD 1278 allele from single heterozygous cells.
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Affiliation(s)
- J Aquiles Sanchez
- Department of Biology, MS 008, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
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Li YT, Maskos K, Chou CW, Cole RB, Li SC. Presence of an unusual GM2 derivative, taurine-conjugated GM2, in Tay-Sachs brain. J Biol Chem 2003; 278:35286-91. [PMID: 12829702 DOI: 10.1074/jbc.m306126200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Tay-Sachs disease (TSD) is a classical glycosphingolipid (GSL) storage disease. Although the genetic and biochemical bases for a massive cerebral accumulation of ganglioside GM2 in TSD have been well established, the mechanism for the neural dysfunction in TSD remains elusive. Upon analysis of GSLs from a variant B TS brain, we have detected a novel GSL that has not been previously revealed. We have isolated this GSL in pure form. Using NMR spectroscopy, mass spectrometry, and chemical synthesis, the structure of this unusual GSL was established to be a taurine-conjugated GM2 (tauro-GM2) in which the carboxyl group of N-acetylneuraminic acid was amidated by taurine. Using a rabbit anti-tauro-GM2 serum, we also detected the presence of tauro-GM2 in three other small brain samples from one variant B and two variant O TSD patients. On the other hand, tauro-GM2 was not found in three normal human brain samples. The presence of tauro-GM2 in TS brains, but not in normal brains, indicates the possible association of this unusual GM2 derivative with the pathogenesis of TSD. Our findings point to taurine conjugation as a heretofore unelucidated mechanism for TS brain to cope with water-insoluble GM2.
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Affiliation(s)
- Yu-Teh Li
- Department of Biochemistry, Tulane University Health Sciences Center School of Medicine, New Orleans, Louisiana 70112, USA.
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