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Skurat AV, Segvich DM, Contreras CJ, Hu YC, Hurley TD, DePaoli-Roach AA, Roach PJ. Impaired malin expression and interaction with partner proteins in Lafora disease. J Biol Chem 2024; 300:107271. [PMID: 38588813 PMCID: PMC11063907 DOI: 10.1016/j.jbc.2024.107271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/10/2024] Open
Abstract
Lafora disease (LD) is an autosomal recessive myoclonus epilepsy with onset in the teenage years leading to death within a decade of onset. LD is characterized by the overaccumulation of hyperphosphorylated, poorly branched, insoluble, glycogen-like polymers called Lafora bodies. The disease is caused by mutations in either EPM2A, encoding laforin, a dual specificity phosphatase that dephosphorylates glycogen, or EMP2B, encoding malin, an E3-ubiquitin ligase. While glycogen is a widely accepted laforin substrate, substrates for malin have been difficult to identify partly due to the lack of malin antibodies able to detect malin in vivo. Here we describe a mouse model in which the malin gene is modified at the C-terminus to contain the c-myc tag sequence, making an expression of malin-myc readily detectable. Mass spectrometry analyses of immunoprecipitates using c-myc tag antibodies demonstrate that malin interacts with laforin and several glycogen-metabolizing enzymes. To investigate the role of laforin in these interactions we analyzed two additional mouse models: malin-myc/laforin knockout and malin-myc/LaforinCS, where laforin was either absent or the catalytic Cys was genomically mutated to Ser, respectively. The interaction of malin with partner proteins requires laforin but is not dependent on its catalytic activity or the presence of glycogen. Overall, the results demonstrate that laforin and malin form a complex in vivo, which stabilizes malin and enhances interaction with partner proteins to facilitate normal glycogen metabolism. They also provide insights into the development of LD and the rescue of the disease by the catalytically inactive phosphatase.
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Affiliation(s)
- Alexander V Skurat
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Dyann M Segvich
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Christopher J Contreras
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Yueh-Chiang Hu
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Thomas D Hurley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA.
| | - Anna A DePaoli-Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA.
| | - Peter J Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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2
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Mitra S, Chen B, Shelton JM, Nitschke S, Wu J, Covington L, Dear M, Lynn T, Verma M, Nitschke F, Fuseya Y, Iwai K, Evers BM, Minassian BA. Myofiber-type-dependent 'boulder' or 'multitudinous pebble' formations across distinct amylopectinoses. Acta Neuropathol 2024; 147:46. [PMID: 38411740 DOI: 10.1007/s00401-024-02698-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/13/2024] [Accepted: 01/24/2024] [Indexed: 02/28/2024]
Abstract
At least five enzymes including three E3 ubiquitin ligases are dedicated to glycogen's spherical structure. Absence of any reverts glycogen to a structure resembling amylopectin of the plant kingdom. This amylopectinosis (polyglucosan body formation) causes fatal neurological diseases including adult polyglucosan body disease (APBD) due to glycogen branching enzyme deficiency, Lafora disease (LD) due to deficiencies of the laforin glycogen phosphatase or the malin E3 ubiquitin ligase and type 1 polyglucosan body myopathy (PGBM1) due to RBCK1 E3 ubiquitin ligase deficiency. Little is known about these enzymes' functions in glycogen structuring. Toward understanding these functions, we undertake a comparative murine study of the amylopectinoses of APBD, LD and PGBM1. We discover that in skeletal muscle, polyglucosan bodies form as two main types, small and multitudinous ('pebbles') or giant and single ('boulders'), and that this is primarily determined by the myofiber types in which they form, 'pebbles' in glycolytic and 'boulders' in oxidative fibers. This pattern recapitulates what is known in the brain in LD, innumerable dust-like in astrocytes and single giant sized in neurons. We also show that oxidative myofibers are relatively protected against amylopectinosis, in part through highly increased glycogen branching enzyme expression. We present evidence of polyglucosan body size-dependent cell necrosis. We show that sex influences amylopectinosis in genotype, brain region and myofiber-type-specific fashion. RBCK1 is a component of the linear ubiquitin chain assembly complex (LUBAC), the only known cellular machinery for head-to-tail linear ubiquitination critical to numerous cellular pathways. We show that the amylopectinosis of RBCK1 deficiency is not due to loss of linear ubiquitination, and that another function of RBCK1 or LUBAC must exist and operate in the shaping of glycogen. This work opens multiple new avenues toward understanding the structural determinants of the mammalian carbohydrate reservoir critical to neurologic and neuromuscular function and disease.
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Affiliation(s)
- Sharmistha Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA.
| | - Baozhi Chen
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - John M Shelton
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9148, USA
| | - Silvia Nitschke
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Jun Wu
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Lindsay Covington
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9148, USA
| | - Mathew Dear
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Tori Lynn
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Mayank Verma
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Felix Nitschke
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA
| | - Yasuhiro Fuseya
- Department of Molecular and Cellular Physiology, Kyoto University School of Medicine, Kyoto, 606-8501, Japan
| | - Kazuhiro Iwai
- Department of Molecular and Cellular Physiology, Kyoto University School of Medicine, Kyoto, 606-8501, Japan
| | - Bret M Evers
- Departments of Pathology and Ophthalmology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9073, USA
| | - Berge A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9063, USA.
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3
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Kumarasinghe L, Garcia-Gimeno MA, Ramirez J, Mayor U, Zugaza JL, Sanz P. P-Rex1 is a novel substrate of the E3 ubiquitin ligase Malin associated with Lafora disease. Neurobiol Dis 2023; 177:105998. [PMID: 36638890 PMCID: PMC10682699 DOI: 10.1016/j.nbd.2023.105998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/29/2022] [Accepted: 01/09/2023] [Indexed: 01/12/2023] Open
Abstract
Laforin and Malin are two proteins that are encoded by the genes EPM2A and EPM2B, respectively. Laforin is a glucan phosphatase and Malin is an E3-ubiquitin ligase, and these two proteins function as a complex. Mutations occurring at the level of one of the two genes lead to the accumulation of an aberrant form of glycogen meant to cluster in polyglucosans that go under the name of Lafora bodies. Individuals affected by the appearance of these polyglucosans, especially at the cerebral level, experience progressive neurodegeneration and several episodes of epilepsy leading to the manifestation of a fatal form of a rare disease called Lafora disease (LD), for which, to date, no treatment is available. Despite the different dysfunctions described for this disease, many molecular aspects still demand elucidation. An effective way to unknot some of the nodes that prevent the achievement of better knowledge of LD is to focus on the substrates that are ubiquitinated by the E3-ubiquitin ligase Malin. Some substrates have already been provided by previous studies based on protein-protein interaction techniques and have been associated with some alterations that mark the disease. In this work, we have used an unbiased alternative approach based on the activity of Malin as an E3-ubiquitin ligase. We report the discovery of novel bonafide substrates of Malin and have characterized one of them more deeply, namely PIP3-dependent Rac exchanger 1 (P-Rex1). The analysis conducted upon this substrate sets the genesis of the delineation of a molecular pathway that leads to altered glucose uptake, which could be one of the origin of the accumulation of the polyglucosans present in the disease.
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Affiliation(s)
- L Kumarasinghe
- Instituto de Biomedicina de Valencia, IBV-CSIC, 46010, Valencia, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)-ISCIII, 28029 Madrid, Spain
| | - M A Garcia-Gimeno
- Department of Biotechnology, Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural (ETSIAMN), Universitat Politécnica de València, 46022, Valencia, Spain
| | - J Ramirez
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, UPV/EHU, Leioa, Bizkaia, Spain
| | - U Mayor
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, UPV/EHU, Leioa, Bizkaia, Spain; Ikerbasque, Basque Foundation for Science, Plaza Euskadi, 48009 Bilbao, Spain
| | - J L Zugaza
- Ikerbasque, Basque Foundation for Science, Plaza Euskadi, 48009 Bilbao, Spain; Achucarro Basque Center for Neuroscience, Scientific Park UPV/EHU, 48940 Leioa, Bizkaia, Spain; Department of Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, UPV/EHU, 48940 Leioa, Bizkaia, Spain
| | - P Sanz
- Instituto de Biomedicina de Valencia, IBV-CSIC, 46010, Valencia, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)-ISCIII, 28029 Madrid, Spain.
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4
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Mitra S, Chen B, Wang P, Chown EE, Dear M, Guisso DR, Mariam U, Wu J, Gumusgoz E, Minassian BA. Laforin targets malin to glycogen in Lafora progressive myoclonus epilepsy. Dis Model Mech 2023; 16:dmm049802. [PMID: 36511140 PMCID: PMC9844227 DOI: 10.1242/dmm.049802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 12/01/2022] [Indexed: 12/15/2022] Open
Abstract
Glycogen is the largest cytosolic macromolecule and is kept in solution through a regular system of short branches allowing hydration. This structure was thought to solely require balanced glycogen synthase and branching enzyme activities. Deposition of overlong branched glycogen in the fatal epilepsy Lafora disease (LD) indicated involvement of the LD gene products laforin and the E3 ubiquitin ligase malin in regulating glycogen structure. Laforin binds glycogen, and LD-causing mutations disrupt this binding, laforin-malin interactions and malin's ligase activity, all indicating a critical role for malin. Neither malin's endogenous function nor location had previously been studied due to lack of suitable antibodies. Here, we generated a mouse in which the native malin gene is tagged with the FLAG sequence. We show that the tagged gene expresses physiologically, malin localizes to glycogen, laforin and malin indeed interact, at glycogen, and malin's presence at glycogen depends on laforin. These results, and mice, open the way to understanding unknown mechanisms of glycogen synthesis critical to LD and potentially other much more common diseases due to incompletely understood defects in glycogen metabolism.
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Affiliation(s)
- Sharmistha Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Baozhi Chen
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Peixiang Wang
- Program in Genetics and Genome Biology, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Erin E. Chown
- Program in Genetics and Genome Biology, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Mathew Dear
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Dikran R. Guisso
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ummay Mariam
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jun Wu
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Emrah Gumusgoz
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Berge A. Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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5
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The different autophagy degradation pathways and neurodegeneration. Neuron 2022; 110:935-966. [PMID: 35134347 PMCID: PMC8930707 DOI: 10.1016/j.neuron.2022.01.017] [Citation(s) in RCA: 154] [Impact Index Per Article: 77.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/31/2021] [Accepted: 01/11/2022] [Indexed: 12/11/2022]
Abstract
The term autophagy encompasses different pathways that route cytoplasmic material to lysosomes for degradation and includes macroautophagy, chaperone-mediated autophagy, and microautophagy. Since these pathways are crucial for degradation of aggregate-prone proteins and dysfunctional organelles such as mitochondria, they help to maintain cellular homeostasis. As post-mitotic neurons cannot dilute unwanted protein and organelle accumulation by cell division, the nervous system is particularly dependent on autophagic pathways. This dependence may be a vulnerability as people age and these processes become less effective in the brain. Here, we will review how the different autophagic pathways may protect against neurodegeneration, giving examples of both polygenic and monogenic diseases. We have considered how autophagy may have roles in normal CNS functions and the relationships between these degradative pathways and different types of programmed cell death. Finally, we will provide an overview of recently described strategies for upregulating autophagic pathways for therapeutic purposes.
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6
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Shahal T, Segev E, Konstantinovsky T, Marcus Y, Shefer G, Pasmanik-Chor M, Buch A, Ebenstein Y, Zimmet P, Stern N. Deconvolution of the epigenetic age discloses distinct inter-personal variability in epigenetic aging patterns. Epigenetics Chromatin 2022; 15:9. [PMID: 35255955 PMCID: PMC8900303 DOI: 10.1186/s13072-022-00441-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 02/21/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The epigenetic age can now be extrapolated from one of several epigenetic clocks, which are based on age-related changes in DNA methylation levels at specific multiple CpG sites. Accelerated aging, calculated from the discrepancy between the chronological age and the epigenetic age, has shown to predict morbidity and mortality rate. We assumed that deconvolution of epigenetic age to its components could shed light on the diversity of epigenetic, and by inference, on inter-individual variability in the causes of biological aging. RESULTS Using the Horvath original epigenetic clock, we identified several CpG sites linked to distinct genes that quantitatively explain much of the inter-personal variability in epigenetic aging, with CpG sites related to secretagogin and malin being the most variable. We show that equal epigenetic age in different subjects can result from variable contribution size of the same CpG sites to the total epigenetic age. In a healthy cohort, the most variable CpG sites are responsible for accelerated and decelerated epigenetic aging, relative to chronological age. CONCLUSIONS Of the 353 CpG sites that form the basis for the Horvath epigenetic age, we have found the CpG sites that are responsible for accelerated and decelerated epigenetic aging in healthy subjects. However, the relative contribution of each site to aging varies between individuals, leading to variable personal aging patterns. Our findings pave the way to form personalized aging cards allowing the identification of specific genes related to CpG sites, as aging markers, and perhaps treatment of these targets in order to hinder undesirable age drifting.
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Affiliation(s)
- Tamar Shahal
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Department of Chemistry, Tel Aviv University, Tel Aviv, Israel
| | - Elad Segev
- Department of Applied Mathematics, Holon Institute of Technology, Holon, Israel
| | - Thomas Konstantinovsky
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Department of Applied Mathematics, Holon Institute of Technology, Holon, Israel
| | - Yonit Marcus
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,The Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Gabi Shefer
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Metsada Pasmanik-Chor
- Bioinformatics Unit, The George S. Wise Faculty of Life Science, Tel Aviv University, Tel Aviv, Israel
| | - Assaf Buch
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yuval Ebenstein
- Department of Chemistry, Tel Aviv University, Tel Aviv, Israel
| | - Paul Zimmet
- Department of Diabetes, Monash University School of Medicine, Melbourne, Australia
| | - Naftali Stern
- The Sagol Center for Epigenetics of Aging and Metabolism, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv-Sourasky Medical Center; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. .,The Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.
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7
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Galvão I, Sousa LP, Teixeira MM, Pinho V. PI3K Isoforms in Cell Signalling and Innate Immune Cell Responses. Curr Top Microbiol Immunol 2022; 436:147-164. [PMID: 36243843 DOI: 10.1007/978-3-031-06566-8_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Phosphoinositide-3-kinases (PI3Ks) are enzymes involved in signalling and modification of the function of all mammalian cells. These enzymes phosphorylate the 3-hydroxyl group of the inositol ring of phosphatidylinositol, resulting in lipid products that act as second messengers responsible for coordinating many cellular functions, including activation, chemotaxis, proliferation and survival. The identification of the functions that are mediated by a specific PI3K isoform is complex and depends on the specific cell type and inflammatory context. In this chapter we will focus on the role of PI3K isoforms in the context of innate immunity, focusing on the mechanisms by which PI3K signalling regulates phagocytosis, the activation of immunoglobulin, chemokine and cytokines receptors, production of ROS and cell migration, and how PI3K signalling plays a central role in host defence against infections and tissue injury.
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Affiliation(s)
- Izabela Galvão
- Immunopharmacology Laboratory, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Resolution of Inflammation Laboratory, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Lirlândia P Sousa
- Signalling in Inflammation Laboratory, Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Mauro M Teixeira
- Immunopharmacology Laboratory, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Vanessa Pinho
- Resolution of Inflammation Laboratory, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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8
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Mitra S, Gumusgoz E, Minassian BA. Lafora disease: Current biology and therapeutic approaches. Rev Neurol (Paris) 2021; 178:315-325. [PMID: 34301405 DOI: 10.1016/j.neurol.2021.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/21/2021] [Accepted: 06/16/2021] [Indexed: 12/19/2022]
Abstract
The ubiquitin system impacts most cellular processes and is altered in numerous neurodegenerative diseases. However, little is known about its role in neurodegenerative diseases due to disturbances of glycogen metabolism such as Lafora disease (LD). In LD, insufficiently branched and long-chained glycogen forms and precipitates into insoluble polyglucosan bodies (Lafora bodies), which drive neuroinflammation, neurodegeneration and epilepsy. LD is caused by mutations in the gene encoding the glycogen phosphatase laforin or the gene coding for the laforin interacting partner ubiquitin E3 ligase malin. The role of the malin-laforin complex in regulating glycogen structure remains with full of gaps. In this review we bring together the disparate body of data on these two proteins and propose a mechanistic hypothesis of the disease in which malin-laforin's role to monitor and prevent over-elongation of glycogen branch chains, which drive glycogen molecules to precipitate and accumulate into Lafora bodies. We also review proposed connections between Lafora bodies and the ensuing neuroinflammation, neurodegeneration and intractable epilepsy. Finally, we review the exciting activities in developing therapies for Lafora disease based on replacing the missing genes, slowing the enzyme - glycogen synthase - that over-elongates glycogen branches, and introducing enzymes that can digest Lafora bodies. Much more work is needed to fill the gaps in glycogen metabolism in which laforin and malin operate. However, knowledge appears already adequate to advance disease course altering therapies for this catastrophic fatal disease.
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Affiliation(s)
- S Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - E Gumusgoz
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - B A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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9
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TRIM32 and Malin in Neurological and Neuromuscular Rare Diseases. Cells 2021; 10:cells10040820. [PMID: 33917450 PMCID: PMC8067510 DOI: 10.3390/cells10040820] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/01/2021] [Accepted: 04/04/2021] [Indexed: 12/27/2022] Open
Abstract
Tripartite motif (TRIM) proteins are RING E3 ubiquitin ligases defined by a shared domain structure. Several of them are implicated in rare genetic diseases, and mutations in TRIM32 and TRIM-like malin are associated with Limb-Girdle Muscular Dystrophy R8 and Lafora disease, respectively. These two proteins are evolutionary related, share a common ancestor, and both display NHL repeats at their C-terminus. Here, we revmniew the function of these two related E3 ubiquitin ligases discussing their intrinsic and possible common pathophysiological pathways.
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10
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Khan I, Baig MH, Mahfooz S, Rahim M, Karacam B, Elbasan EB, Ulasov I, Dong JJ, Hatiboglu MA. Deciphering the Role of Autophagy in Treatment of Resistance Mechanisms in Glioblastoma. Int J Mol Sci 2021; 22:ijms22031318. [PMID: 33525678 PMCID: PMC7865981 DOI: 10.3390/ijms22031318] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023] Open
Abstract
Autophagy is a process essential for cellular energy consumption, survival, and defense mechanisms. The role of autophagy in several types of human cancers has been explicitly explained; however, the underlying molecular mechanism of autophagy in glioblastoma remains ambiguous. Autophagy is thought to be a “double-edged sword”, and its effect on tumorigenesis varies with cell type. On the other hand, autophagy may play a significant role in the resistance mechanisms against various therapies. Therefore, it is of the utmost importance to gain insight into the molecular mechanisms deriving the autophagy-mediated therapeutic resistance and designing improved treatment strategies for glioblastoma. In this review, we discuss autophagy mechanisms, specifically its pro-survival and growth-suppressing mechanisms in glioblastomas. In addition, we try to shed some light on the autophagy-mediated activation of the cellular mechanisms supporting radioresistance and chemoresistance in glioblastoma. This review also highlights autophagy’s involvement in glioma stem cell behavior, underlining its role as a potential molecular target for therapeutic interventions.
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Affiliation(s)
- Imran Khan
- Department of Molecular Biology, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Yalıköy Mahallesi, Beykoz, 34820 Istanbul, Turkey; (I.K.); (S.M.); (B.K.)
| | - Mohammad Hassan Baig
- Department of Family Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 06273, Korea;
| | - Sadaf Mahfooz
- Department of Molecular Biology, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Yalıköy Mahallesi, Beykoz, 34820 Istanbul, Turkey; (I.K.); (S.M.); (B.K.)
| | - Moniba Rahim
- Department of Biosciences, Integral University, Lucknow, Uttar Pradesh 226026, India;
| | - Busra Karacam
- Department of Molecular Biology, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Yalıköy Mahallesi, Beykoz, 34820 Istanbul, Turkey; (I.K.); (S.M.); (B.K.)
| | - Elif Burce Elbasan
- Department of Neurosurgery, Bezmialem Vakif University Medical School, Vatan Street, Fatih, 34093 Istanbul, Turkey;
| | - Ilya Ulasov
- Group of Experimental Biotherapy and Diagnostic, Institute for Regenerative Medicine, World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov First Moscow State Medical University, 119991 Moscow, Russia;
| | - Jae-June Dong
- Department of Family Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 06273, Korea;
- Correspondence: (J.-J.D.); (M.A.H.)
| | - Mustafa Aziz Hatiboglu
- Department of Molecular Biology, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Yalıköy Mahallesi, Beykoz, 34820 Istanbul, Turkey; (I.K.); (S.M.); (B.K.)
- Department of Neurosurgery, Bezmialem Vakif University Medical School, Vatan Street, Fatih, 34093 Istanbul, Turkey;
- Correspondence: (J.-J.D.); (M.A.H.)
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11
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Ohashi Y. Class III phosphatidylinositol 3-kinase complex I subunit NRBF2/Atg38 - from cell and structural biology to health and disease. Autophagy 2021; 17:3897-3907. [PMID: 33459128 PMCID: PMC8726667 DOI: 10.1080/15548627.2021.1872240] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Macroautophagy/autophagy is triggered by various starvation and stress conditions. The phospholipid phosphatidylinositol-3-phosphate (PtdIns3P) is essential for the formation of the autophagosome both in yeast and mammals. The class III phosphatidylinositol 3-kinase, PIK3C3C in humans or Vps34 in yeast, produces PtdIns3P by phosphorylating the 3'-OH position of phosphatidylinositol (PtdIns). In order to synthesize PtdIns3P for the initiation of autophagy, PIK3C3/Vps34 has a heterotetrameric core, the PIK3C3 complex I (hereafter complex I) composed of PIK3C3/Vps34, PIK3R4/Vps15, BECN1/Vps30, and ATG14/Atg14. A fifth component of complex I, NRBF2 in mammals and Atg38 in yeast, was found and has been characterized in the past decade. The field has been expanding from cell and structural biology to mouse model and cohort studies. Here I will summarize the structures and models of complex I binding NRBF2/Atg38, its intracellular roles, and its involvement in health and disease. Along with this expansion of the field, different conclusions have been drawn in several topics. I will clarify what has and has not been agreed, and what is to be clarified in the future.
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Affiliation(s)
- Yohei Ohashi
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, UK
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12
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Perez-Jimenez E, Viana R, Muñoz-Ballester C, Vendrell-Tornero C, Moll-Diaz R, Garcia-Gimeno MA, Sanz P. Endocytosis of the glutamate transporter 1 is regulated by laforin and malin: Implications in Lafora disease. Glia 2020; 69:1170-1183. [PMID: 33368637 DOI: 10.1002/glia.23956] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/10/2020] [Accepted: 12/10/2020] [Indexed: 01/13/2023]
Abstract
Lafora disease (LD) is a fatal rare type of progressive myoclonus epilepsy that appears during early adolescence. The disease is caused by mutations in EPM2A or EPM2B genes, which encode laforin, a glucan phosphatase, and malin, an E3-ubiquitin ligase, respectively. Although the exact roles of laforin and malin are still not well understood, it is known that they work as a complex in which laforin recruits targets that will be ubiquitinated by malin. Recently, we suggested that the type of epilepsy that accompanies LD could be due to deficiencies in the function of the astrocytic glutamate transporter GLT-1. We described that astrocytes from LD mouse models presented decreased levels of GLT-1 at the plasma membrane, leading to increased levels of glutamate in the brain parenchyma. In this work, we present evidence indicating that in the absence of a functional laforin/malin complex (as in LD cellular models) there is an alteration in the ubiquitination of GLT-1, which could be the cause of the reduction in the levels of GLT-1 at the plasma membrane. On the contrary, overexpression of the laforin/malin complex promotes the retention of GLT-1 at the plasma membrane. This retention may be due to the direct ubiquitination of GLT-1 and/or to an opposite effect of this complex on the dynamics of the Nedd4.2-mediated endocytosis of the transporter. This work, therefore, presents new pieces of evidence on the regulation of GLT-1 by the laforin/malin complex, highlighting its value as a therapeutic target for the amelioration of the type of epilepsy that accompanies LD.
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Affiliation(s)
- Eva Perez-Jimenez
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
| | - Rosa Viana
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
| | - Carmen Muñoz-Ballester
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
| | - Carlos Vendrell-Tornero
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
| | - Raquel Moll-Diaz
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
| | | | - Pascual Sanz
- Consejo Superior de Investigaciones Científicas, Instituto de Biomedicina de Valencia, Valencia, Spain.,CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Biomedicina de Valencia, Valencia, Spain
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13
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Xu JL, Yuan L, Tang YC, Xu ZY, Xu HD, Cheng XD, Qin JJ. The Role of Autophagy in Gastric Cancer Chemoresistance: Friend or Foe? Front Cell Dev Biol 2020; 8:621428. [PMID: 33344463 PMCID: PMC7744622 DOI: 10.3389/fcell.2020.621428] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 11/12/2020] [Indexed: 12/12/2022] Open
Abstract
Gastric cancer is the third most common cause of cancer-related death worldwide. Drug resistance is the main inevitable and vital factor leading to a low 5-year survival rate for patients with gastric cancer. Autophagy, as a highly conserved homeostatic pathway, is mainly regulated by different proteins and non-coding RNAs (ncRNAs) and plays dual roles in drug resistance of gastric cancer. Thus, targeting key regulatory nodes in the process of autophagy by small molecule inhibitors or activators has become one of the most promising strategies for the treatment of gastric cancer in recent years. In this review, we provide a systematic summary focusing on the relationship between autophagy and chemotherapy resistance in gastric cancer. We comprehensively discuss the roles and molecular mechanisms of multiple proteins and the emerging ncRNAs including miRNAs and lncRNAs in the regulation of autophagy pathways and gastric cancer chemoresistance. We also summarize the regulatory effects of autophagy inhibitor and activators on gastric cancer chemoresistance. Understanding the vital roles of autophagy in gastric cancer chemoresistance will provide novel opportunities to develop promising therapeutic strategies for gastric cancer.
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Affiliation(s)
- Jing-Li Xu
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China.,The First Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, China
| | - Li Yuan
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China.,The First Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, China
| | - Yan-Cheng Tang
- School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tsai, Hong Kong, China
| | - Zhi-Yuan Xu
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China
| | - Han-Dong Xu
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China.,The First Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, China
| | - Xiang-Dong Cheng
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China
| | - Jiang-Jiang Qin
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Hangzhou, China.,Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China
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14
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Lescouzères L, Bomont P. E3 Ubiquitin Ligases in Neurological Diseases: Focus on Gigaxonin and Autophagy. Front Physiol 2020; 11:1022. [PMID: 33192535 PMCID: PMC7642974 DOI: 10.3389/fphys.2020.01022] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/27/2020] [Indexed: 12/13/2022] Open
Abstract
Ubiquitination is a dynamic post-translational modification that regulates the fate of proteins and therefore modulates a myriad of cellular functions. At the last step of this sophisticated enzymatic cascade, E3 ubiquitin ligases selectively direct ubiquitin attachment to specific substrates. Altogether, the ∼800 distinct E3 ligases, combined to the exquisite variety of ubiquitin chains and types that can be formed at multiple sites on thousands of different substrates confer to ubiquitination versatility and infinite possibilities to control biological functions. E3 ubiquitin ligases have been shown to regulate behaviors of proteins, from their activation, trafficking, subcellular distribution, interaction with other proteins, to their final degradation. Largely known for tagging proteins for their degradation by the proteasome, E3 ligases also direct ubiquitinated proteins and more largely cellular content (organelles, ribosomes, etc.) to destruction by autophagy. This multi-step machinery involves the creation of double membrane autophagosomes in which engulfed material is degraded after fusion with lysosomes. Cooperating in sustaining homeostasis, actors of ubiquitination, proteasome and autophagy pathways are impaired or mutated in wide range of human diseases. From initial discovery of pathogenic mutations in the E3 ligase encoding for E6-AP in Angelman syndrome and Parkin in juvenile forms of Parkinson disease, the number of E3 ligases identified as causal gene for neurological diseases has considerably increased within the last years. In this review, we provide an overview of these diseases, by classifying the E3 ubiquitin ligase types and categorizing the neurological signs. We focus on the Gigaxonin-E3 ligase, mutated in giant axonal neuropathy and present a comprehensive analysis of the spectrum of mutations and the recent biological models that permitted to uncover novel mechanisms of action. Then, we discuss the common functions shared by Gigaxonin and the other E3 ligases in cytoskeleton architecture, cell signaling and autophagy. In particular, we emphasize their pivotal roles in controlling multiple steps of the autophagy pathway. In light of the various targets and extending functions sustained by a single E3 ligase, we finally discuss the challenge in understanding the complex pathological cascade underlying disease and in designing therapeutic approaches that can apprehend this complexity.
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Affiliation(s)
- Léa Lescouzères
- ATIP-Avenir Team, INM, INSERM, University of Montpellier, Montpellier, France
| | - Pascale Bomont
- ATIP-Avenir Team, INM, INSERM, University of Montpellier, Montpellier, France
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15
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Oxidative Stress, a Crossroad Between Rare Diseases and Neurodegeneration. Antioxidants (Basel) 2020; 9:antiox9040313. [PMID: 32326494 PMCID: PMC7222183 DOI: 10.3390/antiox9040313] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/06/2020] [Accepted: 04/13/2020] [Indexed: 02/06/2023] Open
Abstract
Oxidative stress is an imbalance between production and accumulation of oxygen reactive species and/or reactive nitrogen species in cells and tissues, and the capacity of detoxifying these products, using enzymatic and non-enzymatic components, such as glutathione. Oxidative stress plays roles in several pathological processes in the nervous system, such as neurotoxicity, neuroinflammation, ischemic stroke, and neurodegeneration. The concepts of oxidative stress and rare diseases were formulated in the eighties, and since then, the link between them has not stopped growing. The present review aims to expand knowledge in the pathological processes associated with oxidative stress underlying some groups of rare diseases: Friedreich’s ataxia, diseases with neurodegeneration with brain iron accumulation, Charcot-Marie-Tooth as an example of rare neuromuscular disorders, inherited retinal dystrophies, progressive myoclonus epilepsies, and pediatric drug-resistant epilepsies. Despite the discrimination between cause and effect may not be easy on many occasions, all these conditions are Mendelian rare diseases that share oxidative stress as a common factor, and this may represent a potential target for therapies.
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16
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Zou L, Lei H, Shen J, Liu X, Zhang X, Wu L, Hao J, Jiang W, Hu Z. HO-1 induced autophagy protects against IL-1 β-mediated apoptosis in human nucleus pulposus cells by inhibiting NF-κB. Aging (Albany NY) 2020; 12:2440-2452. [PMID: 32015215 PMCID: PMC7041769 DOI: 10.18632/aging.102753] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/07/2020] [Indexed: 01/01/2023]
Abstract
In this study, we investigated the role of heme oxygenase-1 (HO-1) in intervertebral disc degeneration (IDD) by assessing the effects of HO-1 overexpression on IL-1β-induced apoptosis in nucleus pulposus cells (NPCs). Immunohistochemical staining showed HO-1 expression to be lower in NPCs from IDD patients than from patients with lumbar vertebral fractures (LVF). Western blot analysis showed HO-1 and LC3-II/I levels to be lower in NP tissues from IDD patients than from LVF patients, suggesting suppression of autophagy in degenerative intervertebral disc. Consistent with that idea, autophagy was increased in HO-1-overexpressing NPCs while IL-1β-induced apoptosis was reduced. These effects were reversed by treatment with the early autophagy inhibitor 3-methyl adenine, which suggests HO-1-induced autophagy suppresses IL-1β-induced apoptosis in NPCs. HO-1 overexpression promoted autophagy by increasing levels of Beclin-1/PI3KC3 complex. Phospho-P65 levels were lower in HO-1-overexpressing NPCs, suggesting inhibition of NF-κB-mediated apoptosis. Our study thus demonstrates that HO-1 promotes autophagy by enhancing formation of Beclin-1/PI3KC3 complex and suppresses IL-1β-induced apoptosis by inhibiting NF-κB. We suggest that HO-1 is a potential therapeutic target to alleviate IDD.
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Affiliation(s)
- Luetao Zou
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Hongyan Lei
- Department of the First Clinical Medicine, Chongqing Medical University, Chongqing 400016, China
| | - Jieliang Shen
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Xulin Liu
- Department of the First Clinical Medicine, Chongqing Medical University, Chongqing 400016, China
| | - Xiang Zhang
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Longxi Wu
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Jie Hao
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Wei Jiang
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Zhenming Hu
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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