1
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Dingjan T, Futerman AH. Fine-tuned protein-lipid interactions in biological membranes: exploration and implications of the ORMDL-ceramide negative feedback loop in the endoplasmic reticulum. Front Cell Dev Biol 2024; 12:1457209. [PMID: 39170919 PMCID: PMC11335536 DOI: 10.3389/fcell.2024.1457209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Accepted: 07/26/2024] [Indexed: 08/23/2024] Open
Abstract
Biological membranes consist of a lipid bilayer in which integral membrane proteins are embedded. Based on the compositional complexity of the lipid species found in membranes, and on their specific and selective interactions with membrane proteins, we recently suggested that membrane bilayers can be best described as "finely-tuned molecular machines." We now discuss one such set of lipid-protein interactions by describing a negative feedback mechanism operating in the de novo sphingolipid biosynthetic pathway, which occurs in the membrane of the endoplasmic reticulum, and describe the atomic interactions between the first enzyme in the pathway, namely serine palmitoyl transferase, and the product of the fourth enzyme in the pathway, ceramide. We explore how hydrogen-bonding and hydrophobic interactions formed between Asn13 and Phe63 in the serine palmitoyl transferase complex and ceramide can influence the ceramide content of the endoplasmic reticulum. This example of finely-tuned biochemical interactions raises intriguing mechanistic questions about how sphingolipids and their biosynthetic enzymes could have evolved, particularly in light of their metabolic co-dependence.
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Affiliation(s)
- Tamir Dingjan
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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2
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Saint-Martin Willer A, Montani D, Capuano V, Antigny F. Orai1/STIMs modulators in pulmonary vascular diseases. Cell Calcium 2024; 121:102892. [PMID: 38735127 DOI: 10.1016/j.ceca.2024.102892] [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: 02/21/2024] [Revised: 03/27/2024] [Accepted: 04/23/2024] [Indexed: 05/14/2024]
Abstract
Calcium (Ca2+) is a secondary messenger that regulates various cellular processes. However, Ca2+ mishandling could lead to pathological conditions. Orai1 is a Ca2+channel contributing to the store-operated calcium entry (SOCE) and plays a critical role in Ca2+ homeostasis in several cell types. Dysregulation of Orai1 contributed to severe combined immune deficiency syndrome, some cancers, pulmonary arterial hypertension (PAH), and other cardiorespiratory diseases. During its activation process, Orai1 is mainly regulated by stromal interacting molecule (STIM) proteins, especially STIM1; however, many other regulatory partners have also been recently described. Increasing knowledge about these regulatory partners provides a better view of the downstream signalling pathways of SOCE and offers an excellent opportunity to decipher Orai1 dysregulation in these diseases. These proteins participate in other cellular functions, making them attractive therapeutic targets. This review mainly focuses on Orai1 regulatory partners in the physiological and pathological conditions of the pulmonary circulation and inflammation.
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Affiliation(s)
- Anaïs Saint-Martin Willer
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France; INSERM UMR_S 999 Hypertension pulmonaire: Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, Le Plessis-Robinson, France
| | - David Montani
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France; INSERM UMR_S 999 Hypertension pulmonaire: Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, Le Plessis-Robinson, France; Assistance Publique - Hôpitaux de Paris (AP-HP), Service de Pneumologie et Soins Intensifs Respiratoires, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin-Bicêtre, France
| | - Véronique Capuano
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France; INSERM UMR_S 999 Hypertension pulmonaire: Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, Le Plessis-Robinson, France; Hôptal Marie Lannelongue, Groupe Hospitalier Paris Saint-Joseph, Le Plessis-Robinson, France
| | - Fabrice Antigny
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France; INSERM UMR_S 999 Hypertension pulmonaire: Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.
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3
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Wilkerson JL, Tatum SM, Holland WL, Summers SA. Ceramides are fuel gauges on the drive to cardiometabolic disease. Physiol Rev 2024; 104:1061-1119. [PMID: 38300524 PMCID: PMC11381030 DOI: 10.1152/physrev.00008.2023] [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: 02/14/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/02/2024] Open
Abstract
Ceramides are signals of fatty acid excess that accumulate when a cell's energetic needs have been met and its nutrient storage has reached capacity. As these sphingolipids accrue, they alter the metabolism and survival of cells throughout the body including in the heart, liver, blood vessels, skeletal muscle, brain, and kidney. These ceramide actions elicit the tissue dysfunction that underlies cardiometabolic diseases such as diabetes, coronary artery disease, metabolic-associated steatohepatitis, and heart failure. Here, we review the biosynthesis and degradation pathways that maintain ceramide levels in normal physiology and discuss how the loss of ceramide homeostasis drives cardiometabolic pathologies. We highlight signaling nodes that sense small changes in ceramides and in turn reprogram cellular metabolism and stimulate apoptosis. Finally, we evaluate the emerging therapeutic utility of these unique lipids as biomarkers that forecast disease risk and as targets of ceramide-lowering interventions that ameliorate disease.
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Affiliation(s)
- Joseph L Wilkerson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Sean M Tatum
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - William L Holland
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Scott A Summers
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
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4
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Demkova L, Bugajev V, Adamcova MK, Kuchar L, Grusanovic S, Alberich-Jorda M, Draber P, Halova I. Simultaneous deletion of ORMDL1 and ORMDL3 proteins disrupts immune cell homeostasis. Front Immunol 2024; 15:1376629. [PMID: 38715613 PMCID: PMC11074395 DOI: 10.3389/fimmu.2024.1376629] [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: 01/25/2024] [Accepted: 04/08/2024] [Indexed: 06/04/2024] Open
Abstract
ORMDL3 is a prominent member of a family of highly conserved endoplasmic reticulum resident proteins, ORMs (ORM1 and ORM2) in yeast, dORMDL in Drosophila and ORMDLs (ORMDL1, ORMDL2, and ORMDL3) in mammals. ORMDL3 mediates feedback inhibition of de novo sphingolipid synthesis. Expression levels of ORMDL3 are associated with the development of inflammatory and autoimmune diseases including asthma, systemic lupus erythematosus, type 1 diabetes mellitus and others. It has been shown that simultaneous deletions of other ORMDL family members could potentiate ORMDL3-induced phenotypes. To understand the complex function of ORMDL proteins in immunity in vivo, we analyzed mice with single or double deletions of Ormdl genes. In contrast to other single and double knockouts, simultaneous deletion of ORMDL1 and ORMDL3 proteins disrupted blood homeostasis and reduced immune cell content in peripheral blood and spleens of mice. The reduced number of splenocytes was not caused by aberrant immune cell homing. A competitive bone marrow transplantation assay showed that the development of Ormdl1-/-/Ormdl3-/- B cells was dependent on lymphocyte intrinsic factors. Highly increased sphingolipid production was observed in the spleens and bone marrow of Ormdl1-/-/Ormdl3-/- mice. Slight, yet significant, increase in some sphingolipid species was also observed in the spleens of Ormdl3-/- mice and in the bone marrow of both, Ormdl1-/- and Ormdl3-/- single knockout mice. Taken together, our results demonstrate that the physiological expression of ORMDL proteins is critical for the proper development and circulation of lymphocytes. We also show cell-type specific roles of individual ORMDL family members in the production of different sphingolipid species.
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Affiliation(s)
- Livia Demkova
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Viktor Bugajev
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Miroslava K. Adamcova
- Laboratory of Hemato-Oncology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Ladislav Kuchar
- Research Unit for Rare Diseases, Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Srdjan Grusanovic
- Laboratory of Hemato-Oncology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Meritxell Alberich-Jorda
- Laboratory of Hemato-Oncology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Petr Draber
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Ivana Halova
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
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5
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Sharma J, Khan S, Singh NC, Sahu S, Raj D, Prakash S, Bandyopadhyay P, Sarkar K, Bhosale V, Chandra T, Kumaravelu J, Barthwal MK, Gupta SK, Srivastava M, Guha R, Ammanathan V, Ghoshal UC, Mitra K, Lahiri A. ORMDL3 regulates NLRP3 inflammasome activation by maintaining ER-mitochondria contacts in human macrophages and dictates ulcerative colitis patient outcome. J Biol Chem 2024; 300:107120. [PMID: 38417794 PMCID: PMC11065740 DOI: 10.1016/j.jbc.2024.107120] [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: 08/27/2023] [Revised: 02/06/2024] [Accepted: 02/20/2024] [Indexed: 03/01/2024] Open
Abstract
Genome-wide association studies in inflammatory bowel disease have identified risk loci in the orosomucoid-like protein 3/ORMDL sphingolipid biosynthesis regulator 3 (ORMDL3) gene to confer susceptibility to ulcerative colitis (UC), but the underlying functional relevance remains unexplored. Here, we found that a subpopulation of the UC patients who had higher disease activity shows enhanced expression of ORMDL3 compared to the patients with lower disease activity and the non-UC controls. We also found that the patients showing high ORMDL3 mRNA expression have elevated interleukin-1β cytokine levels indicating positive correlation. Further, knockdown of ORMDL3 in the human monocyte-derived macrophages resulted in significantly reduced interleukin-1β release. Mechanistically, we report for the first time that ORMDL3 contributes to a mounting inflammatory response via modulating mitochondrial morphology and activation of the NLRP3 inflammasome. Specifically, we observed an increased fragmentation of mitochondria and enhanced contacts with the endoplasmic reticulum (ER) during ORMDL3 over-expression, enabling efficient NLRP3 inflammasome activation. We show that ORMDL3 that was previously known to be localized in the ER also becomes localized to mitochondria-associated membranes and mitochondria during inflammatory conditions. Additionally, ORMDL3 interacts with mitochondrial dynamic regulating protein Fis-1 present in the mitochondria-associated membrane. Accordingly, knockdown of ORMDL3 in a dextran sodium sulfate -induced colitis mouse model showed reduced colitis severity. Taken together, we have uncovered a functional role for ORMDL3 in mounting inflammation during UC pathogenesis by modulating ER-mitochondrial contact and dynamics.
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Affiliation(s)
- Jyotsna Sharma
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Shaziya Khan
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Nishakumari C Singh
- Sophisticated Analytical Instrument Facility and Research Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Shikha Sahu
- Department of Gastroenterology, Sanjay Gandhi postgraduate institute of medical sciences, Lucknow, India
| | - Desh Raj
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Shakti Prakash
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | | | - Kabita Sarkar
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Vivek Bhosale
- Toxicology and Experimental Medicine Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Tulika Chandra
- Department of Transfusion Medicine, Kings George Medical University, Lucknow, India
| | - Jagavelu Kumaravelu
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Manoj Kumar Barthwal
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Shashi Kumar Gupta
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Mrigank Srivastava
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India; Molecular Parasitology and Immunology Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Rajdeep Guha
- Lab Animal Facility, CSIR-Central Drug Research Institute, Lucknow, India
| | - Veena Ammanathan
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Uday C Ghoshal
- Department of Gastroenterology, Sanjay Gandhi postgraduate institute of medical sciences, Lucknow, India
| | - Kalyan Mitra
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India; Sophisticated Analytical Instrument Facility and Research Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Amit Lahiri
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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6
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Zhou X, Sampath V, Nadeau KC. Effect of air pollution on asthma. Ann Allergy Asthma Immunol 2024; 132:426-432. [PMID: 38253122 PMCID: PMC10990824 DOI: 10.1016/j.anai.2024.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/16/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024]
Abstract
Asthma is a chronic inflammatory airway disease characterized by respiratory symptoms, variable airflow obstruction, bronchial hyperresponsiveness, and airway inflammation. Exposure to air pollution has been linked to an increased risk of asthma development and exacerbation. This review aims to comprehensively summarize recent data on the impact of air pollution on asthma development and exacerbation. Specifically, we reviewed the effects of air pollution on the pathogenic pathways of asthma, including type 2 and non-type 2 inflammatory responses, and airway epithelial barrier dysfunction. Air pollution promotes the release of epithelial cytokines, driving TH2 responses, and induces oxidative stress and the production of proinflammatory cytokines. The enhanced type 2 inflammation, furthered by air pollution-induced dysfunction of the airway epithelial barrier, may be associated with the exacerbation of asthma. Disruption of the TH17/regulatory T cell balance by air pollutants is also related to asthma exacerbation. As the effects of air pollution exposure may accumulate over time, with potentially stronger impacts in the development of asthma during certain sensitive life periods, we also reviewed the effects of air pollution on asthma across the lifespan. Future research is needed to better characterize the sensitive period contributing to the development of air pollution-induced asthma and to map air pollution-associated epigenetic biomarkers contributing to the epigenetic ages onto asthma-related genes.
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Affiliation(s)
- Xiaoying Zhou
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Vanitha Sampath
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Kari C Nadeau
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
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7
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Syeda SB, Lone MA, Mohassel P, Donkervoort S, Munot P, França MC, Galarza-Brito JE, Eckenweiler M, Asamoah A, Gable K, Majumdar A, Schumann A, Gupta SD, Lakhotia A, Shieh PB, Foley AR, Jackson KE, Chao KR, Winder TL, Catapano F, Feng L, Kirschner J, Muntoni F, Dunn TM, Hornemann T, Bönnemann CG. Recurrent de novo SPTLC2 variant causes childhood-onset amyotrophic lateral sclerosis (ALS) by excess sphingolipid synthesis. J Neurol Neurosurg Psychiatry 2024; 95:103-113. [PMID: 38041679 PMCID: PMC10850718 DOI: 10.1136/jnnp-2023-332132] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/27/2023] [Indexed: 12/03/2023]
Abstract
BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of the upper and lower motor neurons with varying ages of onset, progression and pathomechanisms. Monogenic childhood-onset ALS, although rare, forms an important subgroup of ALS. We recently reported specific SPTLC1 variants resulting in sphingolipid overproduction as a cause for juvenile ALS. Here, we report six patients from six independent families with a recurrent, de novo, heterozygous variant in SPTLC2 c.778G>A [p.Glu260Lys] manifesting with juvenile ALS. METHODS Clinical examination of the patients along with ancillary and genetic testing, followed by biochemical investigation of patients' blood and fibroblasts, was performed. RESULTS All patients presented with early-childhood-onset progressive weakness, with signs and symptoms of upper and lower motor neuron degeneration in multiple myotomes, without sensory neuropathy. These findings were supported on ancillary testing including nerve conduction studies and electromyography, muscle biopsies and muscle ultrasound studies. Biochemical investigations in plasma and fibroblasts showed elevated levels of ceramides and unrestrained de novo sphingolipid synthesis. Our studies indicate that SPTLC2 variant [c.778G>A, p.Glu260Lys] acts distinctly from hereditary sensory and autonomic neuropathy (HSAN)-causing SPTLC2 variants by causing excess canonical sphingolipid biosynthesis, similar to the recently reported SPTLC1 ALS associated pathogenic variants. Our studies also indicate that serine supplementation, which is a therapeutic in SPTLC1 and SPTCL2-associated HSAN, is expected to exacerbate the excess sphingolipid synthesis in serine palmitoyltransferase (SPT)-associated ALS. CONCLUSIONS SPTLC2 is the second SPT-associated gene that underlies monogenic, juvenile ALS and further establishes alterations of sphingolipid metabolism in motor neuron disease pathogenesis. Our findings also have important therapeutic implications: serine supplementation must be avoided in SPT-associated ALS, as it is expected to drive pathogenesis further.
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Affiliation(s)
- Safoora B Syeda
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Museer A Lone
- Institute of Clinical Chemistry, University Hospital Zürich, Zürich, Switzerland
| | - Payam Mohassel
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Pinki Munot
- NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK
| | - Marcondes C França
- Department of Neurology, University of Campinas, Campinas, Sao Paulo, Brazil
| | | | - Matthias Eckenweiler
- Department of Neuropediatrics and Muscle Disorders, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | - Alexander Asamoah
- Norton Children's Medical Group, University of Louisville School of Medicine, Louisville, KY, USA
| | - Kenneth Gable
- Department of Biochemistry and Molecular Biology, Uniformed Services University, Bethesda, Maryland, USA
| | - Anirban Majumdar
- Department of Paediatric Neurology, Bristol Children's Hospital, Bristol, UK
| | - Anke Schumann
- Department of Paediatrics and Adolescent Medicine, Faculty of Medicine, Medical Centre, University of Freiburg, Baden-Württemberg, Germany
| | - Sita D Gupta
- Department of Biochemistry and Molecular Biology, Uniformed Services University, Bethesda, Maryland, USA
| | - Arpita Lakhotia
- Norton Children's Medical Group, University of Louisville School of Medicine, Louisville, KY, USA
- University of Louisville, Louisville, Kentucky, USA
| | - Perry B Shieh
- Department of Neurology and Pediatrics, University of California Los Angeles, Los Angeles, CA, USA
| | - A Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Kelly E Jackson
- Norton Children's Medical Group, University of Louisville School of Medicine, Louisville, KY, USA
| | - Katherine R Chao
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - Francesco Catapano
- Dubowitz Neuromuscular Centre, CL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital, London, UK
| | - Lucy Feng
- Dubowitz Neuromuscular Centre, CL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital, London, UK
| | - Janbernd Kirschner
- Department of Neuropediatrics and Muscle Disorders, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | - Francesco Muntoni
- NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK
- Dubowitz Neuromuscular Centre, CL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital, London, UK
| | - Teresa M Dunn
- Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA
| | - Thorsten Hornemann
- Institute of Clinical Chemistry, University Hospital Zürich, Zürich, Switzerland
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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8
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Kleuser B, Schumacher F, Gulbins E. New Therapeutic Options in Pulmonal Diseases: Sphingolipids and Modulation of Sphingolipid Metabolism. Handb Exp Pharmacol 2024; 284:289-312. [PMID: 37922034 DOI: 10.1007/164_2023_700] [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: 11/05/2023]
Abstract
Sphingolipids are crucial molecules in the respiratory airways. As in most other tissues and organs, in the lung sphingolipids play an essential role as structural constituents as they regulate barrier function and fluidity of cell membranes. A lung-specific feature is the occurrence of sphingolipids as minor structural components in the surfactant. However, sphingolipids are also key signaling molecules involved in airway cell signaling and their dynamical formation and metabolism are important for normal lung physiology. Dysregulation of sphingolipid metabolism and signaling is involved in altering lung tissue and initiates inflammatory processes promoting the pathogenesis of pulmonal diseases including cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), and asthma.In the present review, the important role of specific sphingolipid species in pulmonal diseases will be discussed. Only such an understanding opens up the possibility of developing new therapeutic strategies with the aim of correcting the imbalance in sphingolipid metabolism and signaling. Such delivery strategies have already been studied in animal models of these lung diseases, demonstrating that targeting the sphingolipid profile represents new therapeutic opportunities for lung disorders.
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Affiliation(s)
- Burkhard Kleuser
- Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany.
| | - Fabian Schumacher
- Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
| | - Erich Gulbins
- Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
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9
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Zhu XM, Li L, Bao JD, Wang JY, Daskalov A, Liu XH, Del Poeta M, Lin FC. The biological functions of sphingolipids in plant pathogenic fungi. PLoS Pathog 2023; 19:e1011733. [PMID: 37943805 PMCID: PMC10635517 DOI: 10.1371/journal.ppat.1011733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023] Open
Abstract
Sphingolipids are critically significant in a range of biological processes in animals, plants, and fungi. In mammalian cells, they serve as vital components of the plasma membrane (PM) in maintaining its structure, tension, and fluidity. They also play a key role in a wide variety of biological processes, such as intracellular signal transduction, cell polarization, differentiation, and migration. In plants, sphingolipids are important for cell development and for cell response to environmental stresses. In pathogenic fungi, sphingolipids are crucial for the initiation and the development of infection processes afflicting humans. However, our knowledge on the metabolism and function of the sphingolipid metabolic pathway of pathogenic fungi affecting plants is still very limited. In this review, we discuss recent developments on sphingolipid pathways of plant pathogenic fungi, highlighting their uniqueness and similarity with plants and animals. In addition, we discuss recent advances in the research and development of fungal-targeted inhibitors of the sphingolipid pathway, to gain insights on how we can better control the infection process occurring in plants to prevent or/and to treat fungal infections in crops.
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Affiliation(s)
- Xue-Ming Zhu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Lin Li
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Jian-Dong Bao
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Jiao-Yu Wang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Asen Daskalov
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xiao-Hong Liu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
- Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, United States of America
- Veterans Affairs Medical Center, Northport, New York, United States of America
| | - Fu-Cheng Lin
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
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10
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Demkova L, Bugajev V, Utekal P, Kuchar L, Schuster B, Draber P, Halova I. Simultaneous reduction of all ORMDL proteins decreases the threshold of mast cell activation. Sci Rep 2023; 13:9615. [PMID: 37316542 PMCID: PMC10267218 DOI: 10.1038/s41598-023-36344-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 06/01/2023] [Indexed: 06/16/2023] Open
Abstract
In mammals, the ORMDL family of evolutionarily conserved sphingolipid regulators consists of three highly homologous members, ORMDL1, ORMDL2 and ORMDL3. ORMDL3 gene has been associated with childhood-onset asthma and other inflammatory diseases in which mast cells play an important role. We previously described increased IgE-mediated activation of mast cells with simultaneous deletions of ORMDL2 and ORMDL3 proteins. In this study, we prepared mice with Ormdl1 knockout and thereafter, produced primary mast cells with reduced expression of one, two or all three ORMDL proteins. The lone deletion of ORMDL1, or in combination with ORMDL2, had no effect on sphingolipid metabolism nor IgE-antigen dependent responses in mast cells. Double ORMDL1 and ORMDL3 knockout mast cells displayed enhanced IgE-mediated calcium responses and cytokine production. Silencing of ORMDL3 in mast cells after maturation increased their sensitivity to antigen. Mast cells with reduced levels of all three ORMDL proteins demonstrated pro-inflammatory responses even in the absence of antigen activation. Overall, our results show that reduced levels of ORMDL proteins shift mast cells towards a pro-inflammatory phenotype, which is predominantly dependent on the levels of ORMDL3 expression.
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Affiliation(s)
- Livia Demkova
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Viktor Bugajev
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Pavol Utekal
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Ladislav Kuchar
- Research Unit for Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Björn Schuster
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
- CZ-OPENSCREEN, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Draber
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic.
| | - Ivana Halova
- Laboratory of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic.
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11
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Xie T, Liu P, Wu X, Dong F, Zhang Z, Yue J, Mahawar U, Farooq F, Vohra H, Fang Q, Liu W, Wattenberg BW, Gong X. Ceramide sensing by human SPT-ORMDL complex for establishing sphingolipid homeostasis. Nat Commun 2023; 14:3475. [PMID: 37308477 DOI: 10.1038/s41467-023-39274-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 06/02/2023] [Indexed: 06/14/2023] Open
Abstract
The ORM/ORMDL family proteins function as regulatory subunits of the serine palmitoyltransferase (SPT) complex, which is the initiating and rate-limiting enzyme in sphingolipid biosynthesis. This complex is tightly regulated by cellular sphingolipid levels, but the sphingolipid sensing mechanism is unknown. Here we show that purified human SPT-ORMDL complexes are inhibited by the central sphingolipid metabolite ceramide. We have solved the cryo-EM structure of the SPT-ORMDL3 complex in a ceramide-bound state. Structure-guided mutational analyses reveal the essential function of this ceramide binding site for the suppression of SPT activity. Structural studies indicate that ceramide can induce and lock the N-terminus of ORMDL3 into an inhibitory conformation. Furthermore, we demonstrate that childhood amyotrophic lateral sclerosis (ALS) variants in the SPTLC1 subunit cause impaired ceramide sensing in the SPT-ORMDL3 mutants. Our work elucidates the molecular basis of ceramide sensing by the SPT-ORMDL complex for establishing sphingolipid homeostasis and indicates an important role of impaired ceramide sensing in disease development.
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Affiliation(s)
- Tian Xie
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Peng Liu
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Xinyue Wu
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Feitong Dong
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Zike Zhang
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Jian Yue
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Usha Mahawar
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
| | - Faheem Farooq
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
| | - Hisham Vohra
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
| | - Qi Fang
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Wenchen Liu
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Binks W Wattenberg
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA.
| | - Xin Gong
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
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12
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Kovilakath A, Wohlford G, Cowart LA. Circulating sphingolipids in heart failure. Front Cardiovasc Med 2023; 10:1154447. [PMID: 37229233 PMCID: PMC10203217 DOI: 10.3389/fcvm.2023.1154447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 04/04/2023] [Indexed: 05/27/2023] Open
Abstract
Lack of significant advancements in early detection and treatment of heart failure have precipitated the need for discovery of novel biomarkers and therapeutic targets. Over the past decade, circulating sphingolipids have elicited promising results as biomarkers that premonish adverse cardiac events. Additionally, compelling evidence directly ties sphingolipids to these events in patients with incident heart failure. This review aims to summarize the current literature on circulating sphingolipids in both human cohorts and animal models of heart failure. The goal is to provide direction and focus for future mechanistic studies in heart failure, as well as pave the way for the development of new sphingolipid biomarkers.
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Affiliation(s)
- Anna Kovilakath
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, United States
| | - George Wohlford
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States
| | - L. Ashley Cowart
- Department of Biochemistry and Molecular Biology and the Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, United States
- Richmond Veteran's Affairs Medical Center, Richmond, VA, United States
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13
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Liu P, Xie T, Wu X, Han G, Gupta SD, Zhang Z, Yue J, Dong F, Gable K, Niranjanakumari S, Li W, Wang L, Liu W, Yao R, Cahoon EB, Dunn TM, Gong X. Mechanism of sphingolipid homeostasis revealed by structural analysis of Arabidopsis SPT-ORM1 complex. SCIENCE ADVANCES 2023; 9:eadg0728. [PMID: 36989369 PMCID: PMC10058238 DOI: 10.1126/sciadv.adg0728] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/02/2023] [Indexed: 06/19/2023]
Abstract
The serine palmitoyltransferase (SPT) complex catalyzes the first and rate-limiting step in sphingolipid biosynthesis in all eukaryotes. ORM/ORMDL proteins are negative regulators of SPT that respond to cellular sphingolipid levels. However, the molecular basis underlying ORM/ORMDL-dependent homeostatic regulation of SPT is not well understood. We determined the cryo-electron microscopy structure of Arabidopsis SPT-ORM1 complex, composed of LCB1, LCB2a, SPTssa, and ORM1, in an inhibited state. A ceramide molecule is sandwiched between ORM1 and LCB2a in the cytosolic membrane leaflet. Ceramide binding is critical for the ORM1-dependent SPT repression, and dihydroceramides and phytoceramides differentially affect this repression. A hybrid β sheet, formed by the amino termini of ORM1 and LCB2a and induced by ceramide binding, stabilizes the amino terminus of ORM1 in an inhibitory conformation. Our findings provide mechanistic insights into sphingolipid homeostatic regulation via the binding of ceramide to the SPT-ORM/ORMDL complex that may have implications for plant-specific processes such as the hypersensitive response for microbial pathogen resistance.
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Affiliation(s)
- Peng Liu
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Tian Xie
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Xinyue Wu
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Gongshe Han
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Sita D. Gupta
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Zike Zhang
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Jian Yue
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Feitong Dong
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Kenneth Gable
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Somashekarappa Niranjanakumari
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Wanyuan Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Lin Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Wenchen Liu
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Ruifeng Yao
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Edgar B. Cahoon
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Teresa M. Dunn
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Xin Gong
- Department of Chemical Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
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14
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van Echten-Deckert G. The role of sphingosine 1-phosphate metabolism in brain health and disease. Pharmacol Ther 2023; 244:108381. [PMID: 36907249 DOI: 10.1016/j.pharmthera.2023.108381] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/02/2023] [Accepted: 03/06/2023] [Indexed: 03/13/2023]
Abstract
Lipids are essential structural and functional components of the central nervous system (CNS). Sphingolipids are ubiquitous membrane components which were discovered in the brain in the late 19th century. In mammals, the brain contains the highest concentration of sphingolipids in the body. Sphingosine 1-phosphate (S1P) derived from membrane sphingolipids evokes multiple cellular responses which, depending on its concentration and localization, make S1P a double-edged sword in the brain. In the present review we highlight the role of S1P in brain development and focus on the often contrasting findings regarding its contributions to the initiation, progression and potential recovery of different brain pathologies, including neurodegeneration, multiple sclerosis (MS), brain cancers, and psychiatric illnesses. A detailed understanding of the critical implications of S1P in brain health and disease may open the door for new therapeutic options. Thus, targeting S1P-metabolizing enzymes and/or signaling pathways might help overcome, or at least ameliorate, several brain illnesses.
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15
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Pan X, Dutta D, Lu S, Bellen HJ. Sphingolipids in neurodegenerative diseases. Front Neurosci 2023; 17:1137893. [PMID: 36875645 PMCID: PMC9978793 DOI: 10.3389/fnins.2023.1137893] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
Neurodegenerative Diseases (NDDs) are a group of disorders that cause progressive deficits of neuronal function. Recent evidence argues that sphingolipid metabolism is affected in a surprisingly broad set of NDDs. These include some lysosomal storage diseases (LSDs), hereditary sensory and autonomous neuropathy (HSAN), hereditary spastic paraplegia (HSP), infantile neuroaxonal dystrophy (INAD), Friedreich's ataxia (FRDA), as well as some forms of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). Many of these diseases have been modeled in Drosophila melanogaster and are associated with elevated levels of ceramides. Similar changes have also been reported in vertebrate cells and mouse models. Here, we summarize studies using fly models and/or patient samples which demonstrate the nature of the defects in sphingolipid metabolism, the organelles that are implicated, the cell types that are initially affected, and potential therapeutics for these diseases.
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Affiliation(s)
- Xueyang Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Hugo J. Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
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16
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Li Y, Cao H, Dong T, Wang X, Ma L, Li K, Lou H, Song CP, Ren D. Phosphorylation of the LCB1 subunit of Arabidopsis serine palmitoyltransferase stimulates its activity and modulates sphingolipid biosynthesis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 36738228 DOI: 10.1111/jipb.13461] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Indexed: 06/18/2023]
Abstract
Sphingolipids are the structural components of membrane lipid bilayers and act as signaling molecules in many cellular processes. Serine palmitoyltransferase (SPT) is the first committed and rate-limiting enzyme in the de novo sphingolipids biosynthetic pathway. The core SPT enzyme is a heterodimer consisting of LONG-CHAIN BASE1 (LCB1) and LCB2 subunits. SPT activity is inhibited by orosomucoid proteins and stimulated by small subunits of SPT (ssSPTs). However, whether LCB1 is modified and how such modification might regulate SPT activity have to date been unclear. Here, we show that activation of MITOGEN-ACTIVATED PROTEIN KINASE 3 (MPK3) and MPK6 by upstream MKK9 and treatment with Flg22 (a pathogen-associated molecular pattern) increases SPT activity and induces the accumulation of sphingosine long-chain base t18:0 in Arabidopsis thaliana, with activated MPK3 and MPK6 phosphorylating AtLCB1. Phosphorylation of AtLCB1 strengthened its binding with AtLCB2b, promoted its binding with ssSPTs, and stimulated the formation of higher order oligomeric and active SPT complexes. Our findings therefore suggest a novel regulatory mechanism for SPT activity.
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Affiliation(s)
- Yuan Li
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Hanwei Cao
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Tingting Dong
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaoke Wang
- State Key Laboratory of Agro-Biotechnology and Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Liang Ma
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Kun Li
- Collaborative Innovation Center of Crop Stress Biology, Henan Province. Institute of Plant Stress Biology, School of Life Science, Henan University, Kaifeng, 475001, China
| | - Huiqiang Lou
- State Key Laboratory of Agro-Biotechnology and Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Chun-Peng Song
- Collaborative Innovation Center of Crop Stress Biology, Henan Province. Institute of Plant Stress Biology, School of Life Science, Henan University, Kaifeng, 475001, China
| | - Dongtao Ren
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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17
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Sasset L, Chowdhury KH, Manzo OL, Rubinelli L, Konrad C, Maschek JA, Manfredi G, Holland WL, Di Lorenzo A. Sphingosine-1-phosphate controls endothelial sphingolipid homeostasis via ORMDL. EMBO Rep 2023; 24:e54689. [PMID: 36408842 PMCID: PMC9827560 DOI: 10.15252/embr.202254689] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 10/04/2022] [Accepted: 10/28/2022] [Indexed: 11/22/2022] Open
Abstract
Disruption of sphingolipid homeostasis and signaling has been implicated in diabetes, cancer, cardiometabolic, and neurodegenerative disorders. Yet, mechanisms governing cellular sensing and regulation of sphingolipid homeostasis remain largely unknown. In yeast, serine palmitoyltransferase, catalyzing the first and rate-limiting step of sphingolipid de novo biosynthesis, is negatively regulated by Orm1 and 2. Lowering sphingolipids triggers Orms phosphorylation, upregulation of serine palmitoyltransferase activity and sphingolipid de novo biosynthesis. However, mammalian orthologs ORMDLs lack the N-terminus hosting the phosphosites. Thus, which sphingolipid(s) are sensed by the cells, and mechanisms of homeostasis remain largely unknown. Here, we identify sphingosine-1-phosphate (S1P) as key sphingolipid sensed by cells via S1PRs to maintain homeostasis. The increase in S1P-S1PR signaling stabilizes ORMDLs, restraining SPT activity. Mechanistically, the hydroxylation of ORMDLs at Pro137 allows a constitutive degradation of ORMDLs via ubiquitin-proteasome pathway, preserving SPT activity. Disrupting S1PR/ORMDL axis results in ceramide accrual, mitochondrial dysfunction, impaired signal transduction, all underlying endothelial dysfunction, early event in the onset of cardio- and cerebrovascular diseases. Our discovery may provide the molecular basis for therapeutic intervention restoring sphingolipid homeostasis.
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Affiliation(s)
- Linda Sasset
- Department of Pathology and Laboratory MedicineCardiovascular Research Institute, Weill Cornell MedicineNew YorkNYUSA
- Brain and Mind Research Institute, Weill Cornell MedicineNew YorkNYUSA
| | - Kamrul H Chowdhury
- Department of Nutrition and Integrative PhysiologyUniversity of Utah College of HealthSalt Lake CityUTUSA
| | - Onorina L Manzo
- Department of Pathology and Laboratory MedicineCardiovascular Research Institute, Weill Cornell MedicineNew YorkNYUSA
- Brain and Mind Research Institute, Weill Cornell MedicineNew YorkNYUSA
- Department of PharmacyUniversity of Naples “Federico II”NaplesItaly
| | - Luisa Rubinelli
- Department of Pathology and Laboratory MedicineCardiovascular Research Institute, Weill Cornell MedicineNew YorkNYUSA
- Brain and Mind Research Institute, Weill Cornell MedicineNew YorkNYUSA
| | - Csaba Konrad
- Department of Nutrition and Integrative PhysiologyUniversity of Utah College of HealthSalt Lake CityUTUSA
| | - J Alan Maschek
- Department of Nutrition and Integrative PhysiologyUniversity of Utah College of HealthSalt Lake CityUTUSA
| | - Giovanni Manfredi
- Brain and Mind Research Institute, Weill Cornell MedicineNew YorkNYUSA
| | - William L Holland
- Department of Nutrition and Integrative PhysiologyUniversity of Utah College of HealthSalt Lake CityUTUSA
| | - Annarita Di Lorenzo
- Department of Pathology and Laboratory MedicineCardiovascular Research Institute, Weill Cornell MedicineNew YorkNYUSA
- Brain and Mind Research Institute, Weill Cornell MedicineNew YorkNYUSA
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18
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Choi W, Kang S, Kim J. New insights into the role of the Golgi apparatus in the pathogenesis and therapeutics of human diseases. Arch Pharm Res 2022; 45:671-692. [PMID: 36178581 DOI: 10.1007/s12272-022-01408-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/20/2022] [Indexed: 11/24/2022]
Abstract
The Golgi apparatus is an essential cellular organelle that mediates homeostatic functions, including vesicle trafficking and the post-translational modification of macromolecules. Its unique stacked structure and dynamic functions are tightly regulated, and several Golgi proteins play key roles in the functioning of unconventional protein secretory pathways triggered by cellular stress responses. Recently, an increasing number of studies have implicated defects in Golgi functioning in human diseases such as cancer, neurodegenerative, and immunological disorders. Understanding the extraordinary characteristics of Golgi proteins is important for elucidating its associated intracellular signaling mechanisms and has important ramifications for human health. Therefore, analyzing the mechanisms by which the Golgi participates in disease pathogenesis may be useful for developing novel therapeutic strategies. This review articulates the structural features and abnormalities of the Golgi apparatus reported in various diseases and the suspected mechanisms underlying the Golgi-associated pathologies. Furthermore, we review the potential therapeutic strategies based on Golgi function.
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Affiliation(s)
- Wooseon Choi
- Department of Pharmacology, Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea
| | - Shinwon Kang
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON, Canada
| | - Jiyoon Kim
- Department of Pharmacology, Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea.
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19
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Santos TCB, Dingjan T, Futerman AH. The sphingolipid anteome: implications for evolution of the sphingolipid metabolic pathway. FEBS Lett 2022; 596:2345-2363. [PMID: 35899376 DOI: 10.1002/1873-3468.14457] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/10/2022] [Accepted: 07/19/2022] [Indexed: 11/09/2022]
Abstract
Modern cell membranes contain a bewildering complexity of lipids, among them sphingolipids (SLs). Advances in mass spectrometry have led to the realization that the number and combinatorial complexity of lipids, including SLs, is much greater than previously appreciated. SLs are generated de novo by four enzymes, namely serine palmitoyltransferase, 3-ketodihydrosphingosine reductase, ceramide synthase and dihydroceramide Δ4-desaturase 1. Some of these enzymes depend on the availability of specific substrates and cofactors, which are themselves supplied by other complex metabolic pathways. The evolution of these four enzymes is poorly understood and likely depends on the co-evolution of the metabolic pathways that supply the other essential reaction components. Here, we introduce the concept of the 'anteome', from the Latin ante ('before') to describe the network of metabolic ('omic') pathways that must have converged in order for these pathways to co-evolve and permit SL synthesis. We also suggest that current origin of life and evolutionary models lack appropriate experimental support to explain the appearance of this complex metabolic pathway and its anteome.
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Affiliation(s)
- Tania C B Santos
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Tamir Dingjan
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Anthony H Futerman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
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20
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Weng N, Miller M, Pham AK, Komor AC, Broide DH. Single-base editing of rs12603332 on chromosome 17q21 with a cytosine base editor regulates ORMDL3 and ATF6α expression. Allergy 2022; 77:1139-1149. [PMID: 34525218 DOI: 10.1111/all.15092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/08/2021] [Accepted: 08/09/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Genetic association studies have demonstrated that the SNP rs12603332 located on chromosome 17q21 is highly associated with the risk of the development of asthma. METHODS To determine whether SNP rs1260332 is functional in regulating levels of ORMDL3 expression, we used a Cytosine Base Editor (CBE) plasmid DNA or a CBE mRNA to edit the rs12603332 C risk allele to the T non-risk allele in a human lymphocyte cell line (i.e., Jurkat cells) and in primary human CD4 T cells that carry the C risk alleles. RESULTS Jurkat cells with the rs12603332 C risk allele expressed significantly higher levels of ORMDL3 mRNA, as well as the ORMDL3 regulated gene ATF6α as assessed by qPCR compared to Jurkat clones with the T non-risk allele. In primary human CD4 T cells, we edited 90 ± 3% of the rs12603332-C risk allele to the T non-risk allele and observed a reduction in ORMDL3 and ATF6α expression. Bioinformatic analysis predicted that the non-risk allele rs12603332-T could be the central element of the E-box binding motif (CANNTG) recognized by the E47 transcription factor. An EMSA assay confirmed the bioinformatics prediction demonstrating that a rs12603332-T containing probe bound to the transcription factor E47 in vitro. CONCLUSIONS SNP rs12603332 is functional in regulating the expression of ORMDL3 as well as ORMDL3 regulated gene ATF6α expression. In addition, we demonstrate the use of CBE technology in functionally interrogating asthma-associated SNPs using studies of primary human CD4 cells.
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Affiliation(s)
- Ning Weng
- Department of Medicine University of California San Diego La Jolla California USA
| | - Marina Miller
- Department of Medicine University of California San Diego La Jolla California USA
| | - Alexa K. Pham
- Department of Medicine University of California San Diego La Jolla California USA
| | - Alexis C. Komor
- Department of Chemistry and Biochemistry University of California San Diego La Jolla California USA
| | - David H. Broide
- Department of Medicine University of California San Diego La Jolla California USA
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Chen R, Michaeloudes C, Liang Y, Bhavsar PK, Chung KF, Ip MSM, Mak JCW. ORMDL3 regulates cigarette smoke-induced endoplasmic reticulum stress in airway smooth muscle cells. J Allergy Clin Immunol 2022; 149:1445-1457.e5. [PMID: 34624393 DOI: 10.1016/j.jaci.2021.09.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 09/19/2021] [Accepted: 09/29/2021] [Indexed: 01/12/2023]
Abstract
BACKGROUND Orosomucoid 1-like protein 3 (ORMDL3), a transmembrane protein localized in the endoplasmic reticulum (ER), has been genetically associated with chronic obstructive pulmonary disease (COPD), in addition to childhood-onset asthma. However, the functional role of ORMDL3 in the pathogenesis of COPD is still unknown. OBJECTIVE Because cigarette smoke is the major risk factor for COPD, we aimed to investigate the role of ORMDL3 in cigarette smoke-induced human airway smooth muscle cell (HASMC) injury. METHODS The mRNA and protein expression of ORMDL3 was examined in HASMCs from nonsmokers and smokers without or with COPD. Knockdown of ORMDL3 in primary healthy HASMCs was performed using small interfering RNA before exposure to cigarette smoke medium (CSM) for 24 hours. Inflammatory, proliferative/apoptotic, ER stress, and mitochondrial markers were evaluated. RESULTS Elevation of ORMDL3 mRNA and protein expression was observed in HASMCs of smokers without or with COPD. CSM caused significant upregulation of ORMDL3 expression in healthy nonsmokers. ORMDL3 knockdown regulated CSM-induced inflammation, cell proliferation, and apoptosis. Silencing ORMDL3 led to reduction of CSM-induced ER stress via inhibition of unfolded protein response pathways such as activating transcription factor 6 and protein kinase RNA-like ER kinase. ORMDL3 was also involved in CSM-induced mitochondrial dysfunction via the mitochondrial fission process. CONCLUSIONS We report the induction of ORMDL3 in HASMCs after cigarette smoke exposure. ORMDL3 may mediate cigarette smoke-induced activation of unfolded protein response pathways during airway smooth muscle cell injury.
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Affiliation(s)
- Rui Chen
- Department of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Charalambos Michaeloudes
- National Heart and Lung Institute, Imperial College London, London, United Kingdom; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China
| | - Yingmin Liang
- Department of Medicine, The University of Hong Kong, Hong Kong SAR, China; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China
| | - Pankaj K Bhavsar
- National Heart and Lung Institute, Imperial College London, London, United Kingdom; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China
| | - Kian Fan Chung
- National Heart and Lung Institute, Imperial College London, London, United Kingdom; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China
| | - Mary S M Ip
- Department of Medicine, The University of Hong Kong, Hong Kong SAR, China; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China
| | - Judith C W Mak
- Department of Medicine, The University of Hong Kong, Hong Kong SAR, China; Respiratory Medicine, The University of Hong Kong-Shenzhen Hospital Respiratory Division, Shenzhen, China; Department of Pharmacology & Pharmacy, The University of Hong Kong, Hong Kong SAR, China.
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22
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Worgall TS. Sphingolipids and Asthma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1372:145-155. [DOI: 10.1007/978-981-19-0394-6_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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23
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Sasset L, Di Lorenzo A. Sphingolipid Metabolism and Signaling in Endothelial Cell Functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1372:87-117. [PMID: 35503177 DOI: 10.1007/978-981-19-0394-6_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The endothelium, inner layer of blood vessels, constitutes a metabolically active paracrine, endocrine, and autocrine organ, able to sense the neighboring environment and exert a variety of biological functions important to preserve the health of vasculature, tissues, and organs. Sphingolipids are both fundamental structural components of the eukaryotic membranes and signaling molecules regulating a variety of biological functions. Ceramide and sphingosine-1-phosphate (S1P), bioactive sphingolipids, have emerged as important regulators of cardiovascular functions in health and disease. In this review we discuss recent insights into the role of ceramide and S1P biosynthesis and signaling in regulating endothelial cell functions, in health and diseases. We also highlight advances into the mechanisms regulating serine palmitoyltransferase, the first and rate-limiting enzyme of de novo sphingolipid biosynthesis, with an emphasis on its inhibitors, ORMDL and NOGO-B. Understanding the molecular mechanisms regulating the sphingolipid de novo biosynthesis may provide the foundation for therapeutic modulation of this pathway in a variety of conditions, including cardiovascular diseases, associated with derangement of this pathway.
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Affiliation(s)
- Linda Sasset
- Department of Pathology and Laboratory Medicine, Cardiovascular Research Institute, Feil Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Annarita Di Lorenzo
- Department of Pathology and Laboratory Medicine, Cardiovascular Research Institute, Feil Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
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24
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De Novo Sphingolipid Biosynthesis in Atherosclerosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1372:31-46. [DOI: 10.1007/978-981-19-0394-6_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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25
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Crosstalk between ORMDL3, serine palmitoyltransferase, and 5-lipoxygenase in the sphingolipid and eicosanoid metabolic pathways. J Lipid Res 2021; 62:100121. [PMID: 34560079 PMCID: PMC8527048 DOI: 10.1016/j.jlr.2021.100121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/23/2021] [Accepted: 09/08/2021] [Indexed: 11/21/2022] Open
Abstract
Leukotrienes (LTs) and sphingolipids are critical lipid mediators participating in numerous cellular signal transduction events and developing various disorders, such as bronchial hyperactivity leading to asthma. Enzymatic reactions initiating production of these lipid mediators involve 5-lipoxygenase (5-LO)-mediated conversion of arachidonic acid to LTs and serine palmitoyltransferase (SPT)-mediated de novo synthesis of sphingolipids. Previous studies have shown that endoplasmic reticulum membrane protein ORM1-like protein 3 (ORMDL3) inhibits the activity of SPT and subsequent sphingolipid synthesis. However, the role of ORMDL3 in the synthesis of LTs is not known. In this study, we used peritoneal-derived mast cells isolated from ORMDL3 KO or control mice and examined their calcium mobilization, degranulation, NF-κB inhibitor-α phosphorylation, and TNF-α production. We found that peritoneal-derived mast cells with ORMDL3 KO exhibited increased responsiveness to antigen. Detailed lipid analysis showed that compared with WT cells, ORMDL3-deficient cells exhibited not only enhanced production of sphingolipids but also of LT signaling mediators LTB4, 6t-LTB4, LTC4, LTB5, and 6t-LTB5. The crosstalk between ORMDL3 and 5-LO metabolic pathways was supported by the finding that endogenous ORMDL3 and 5-LO are localized in similar endoplasmic reticulum domains in human mast cells and that ORMDL3 physically interacts with 5-LO. Further experiments showed that 5-LO also interacts with the long-chain 1 and long-chain 2 subunits of SPT. In agreement with these findings, 5-LO knockdown increased ceramide levels, and silencing of SPTLC1 decreased arachidonic acid metabolism to LTs to levels observed upon 5-LO knockdown. These results demonstrate functional crosstalk between the LT and sphingolipid metabolic pathways, leading to the production of lipid signaling mediators.
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26
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Ogi K, Takabayashi T, Tomita K, Sakashita M, Morikawa T, Ninomiya T, Okamoto M, Narita N, Fujieda S. ORMDL3 overexpression facilitates FcεRI-mediated transcription of proinflammatory cytokines and thapsigargin-mediated PERK phosphorylation in RBL-2H3 cells. IMMUNITY INFLAMMATION AND DISEASE 2021; 9:1394-1405. [PMID: 34288557 PMCID: PMC8589398 DOI: 10.1002/iid3.489] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 07/01/2021] [Accepted: 07/05/2021] [Indexed: 12/29/2022]
Abstract
Introduction The chromosomal region 17q21 harbors the human orosomucoid‐like 3 (ORMDL3) gene and has been linked to asthma and other inflammatory diseases. ORMDL3 is involved in the unfolded protein response (UPR), lipid metabolism, and inflammatory reactions. We investigated the effects of ORMDL3 overexpression in RBL‐2H3 cells to determine the contribution of ORMDL3 to inflammatory disease development. Methods We generated ORMDL3 stably overexpressing RBL‐2H3 cells to assess degranulation, transcriptional upregulation of interleukin‐4 (IL‐4), tumor necrosis factor‐α (TNF‐α), monocyte chemoattractant protein‐1 (MCP‐1), and mitogen‐activated protein kinase (MAPK) phosphorylation via FcεRI. In addition, we examined the effects of ORMDL3 overexpression on thapsigargin (TG)‐mediated proinflammatory cytokine transcription and UPR by monitoring MAPK, protein kinase‐like endoplasmic reticulum kinase (PERK), and inositol‐requiring enzyme 1 (IRE1) phosphorylation. Results Overexpression of ORMDL3 enhanced IL‐4, TNF‐α, and MCP‐1 expression after FcεRI cross‐linking, whereas the sphingosine‐1‐phosphate (S1P) agonist FTY720 suppressed this enhancement. There was no significant difference in degranulation and MAPK phosphorylation via FcεRI‐mediated activation between vector‐transfected and ORMDL3‐overexpressing cells. ORMDL3 overexpression accelerated TG‐mediated PERK phosphorylation, while MAPK phosphorylation and proinflammatory cytokine expression showed no significant changes in ORMDL3‐overexpressing cells. Conclusions Our findings suggest that ORMDL3 plays an important role in regulating proinflammatory cytokine expression via the S1P pathway and selectively affects the UPR pathway in mast cells.
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Affiliation(s)
- Kazuhiro Ogi
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Tetsuji Takabayashi
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Kaori Tomita
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Masafumi Sakashita
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Taiyo Morikawa
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Takahiro Ninomiya
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Masayuki Okamoto
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Norihiko Narita
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Shigeharu Fujieda
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
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Wang Q, Liu W, Chen S, Luo Q, Li Y, Peng S, Wang H, Liu X, Chen D. ORMDL1 is upregulated and associated with favorable outcomes in colorectal cancer. Transl Oncol 2021; 14:101171. [PMID: 34243012 PMCID: PMC8273222 DOI: 10.1016/j.tranon.2021.101171] [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] [Received: 02/02/2021] [Revised: 06/12/2021] [Accepted: 06/30/2021] [Indexed: 12/24/2022] Open
Abstract
The association between ORMDL1 expression and clinipathological characteristic in colorectal cancer (CRC) has not been reported before, which is addressed in this study. Although ORMDL1 is generally upregulated in CRC, high expression of ORMDL1 is associated with longer survival; the combination of ORMDL1 expression and other biomarkers to stratify and predict prognosis in CRC is worth to explore. ORMDL1 seems to influence cell cytoskeleton dynamics through Rho GTPase, other than canonical EMT related transcription factors.
Background The ORMDL1 gene is known as a crucial negative regulator of sphingolipid biogenesis. However, the ORMDL1 gene has rarely been studied in a tumor-related context. Therefore, its prognostic value and functional significance in colorectal cancer (CRC) remain to be explored. Methods TCGA CRC cohort analysis, qRT-PCR, and immunohistochemistry (IHC) were used to examine the ORMDL1 expression level. The association between ORMDL1 expression and various clinical characteristics was analyzed by chi-square tests. The overall survival (OS) of CRC patients was analyzed by Kaplan-Meier analysis. In vitro and in vivo cell-based assays were performed to explore the role of ORMDL1 in cell proliferation, invasion and migration. Transcriptional changes in cells with either ORMDL1 knockdown or overexpression were compared and analyzed. Results ORMDL1 was upregulated in CRC tissues in both the TCGA and our cohort. Interestingly, its expression was significantly lower in patients with metastasis than in patients without metastasis, and the high expression group had longer OS than the low expression group. Knockdown of ORMDL1 expression can promote proliferation, colony formation and invasion, while attenuating migration in CRC cell lines. In contrast, forced overexpression of ORMDL1 reduced cell proliferation, colony formation and invasion, while enhancing cell migration. Stable knockdown of ORMDL1 can promote cancer cell proliferation in vivo to some extent. Finally, Rho GTPase activity was influenced by ORMDL1, and the expression of ORMDL1 was enhanced by DTT treatment. Conclusion ORMDL1 is upregulated and may serve as a biomarker to predict favourable outcomes in colorectal cancer.
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Affiliation(s)
- Qian Wang
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Wanjun Liu
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Si Chen
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Qianxin Luo
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Department of Intensive Care Unit, The Sixth Affiliated Hospital, Sun Yat-sen University, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Yichen Li
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Shaoyong Peng
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Huaiming Wang
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Xiaoxia Liu
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China
| | - Daici Chen
- Guangdong Institute of Gastroenterology, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China; Department of Clinical Laboratory, The Sixth Affiliated Hospital, Sun Yat-sen University, 26 Yuancun Er Heng Road, Guangzhou, Guangdong 510655, China.
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28
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Mohassel P, Donkervoort S, Lone MA, Nalls M, Gable K, Gupta SD, Foley AR, Hu Y, Saute JAM, Moreira AL, Kok F, Introna A, Logroscino G, Grunseich C, Nickolls AR, Pourshafie N, Neuhaus SB, Saade D, Gangfuß A, Kölbel H, Piccus Z, Le Pichon CE, Fiorillo C, Ly CV, Töpf A, Brady L, Specht S, Zidell A, Pedro H, Mittelmann E, Thomas FP, Chao KR, Konersman CG, Cho MT, Brandt T, Straub V, Connolly AM, Schara U, Roos A, Tarnopolsky M, Höke A, Brown RH, Lee CH, Hornemann T, Dunn TM, Bönnemann CG. Childhood amyotrophic lateral sclerosis caused by excess sphingolipid synthesis. Nat Med 2021; 27:1197-1204. [PMID: 34059824 PMCID: PMC9309980 DOI: 10.1038/s41591-021-01346-1] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/09/2021] [Indexed: 02/06/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, neurodegenerative disease of the lower and upper motor neurons with sporadic or hereditary occurrence. Age of onset, pattern of motor neuron degeneration and disease progression vary widely among individuals with ALS. Various cellular processes may drive ALS pathomechanisms, but a monogenic direct metabolic disturbance has not been causally linked to ALS. Here we show SPTLC1 variants that result in unrestrained sphingoid base synthesis cause a monogenic form of ALS. We identified four specific, dominantly acting SPTLC1 variants in seven families manifesting as childhood-onset ALS. These variants disrupt the normal homeostatic regulation of serine palmitoyltransferase (SPT) by ORMDL proteins, resulting in unregulated SPT activity and elevated levels of canonical SPT products. Notably, this is in contrast with SPTLC1 variants that shift SPT amino acid usage from serine to alanine, result in elevated levels of deoxysphingolipids and manifest with the alternate phenotype of hereditary sensory and autonomic neuropathy. We custom designed small interfering RNAs that selectively target the SPTLC1 ALS allele for degradation, leave the normal allele intact and normalize sphingolipid levels in vitro. The role of primary metabolic disturbances in ALS has been elusive; this study defines excess sphingolipid biosynthesis as a fundamental metabolic mechanism for motor neuron disease.
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Affiliation(s)
- Payam Mohassel
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Museer A Lone
- Institute of Clinical Chemistry, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Matthew Nalls
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Kenneth Gable
- Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA
| | - Sita D Gupta
- Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA
| | - A Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Ying Hu
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Jonas Alex Morales Saute
- Medical Genetics division and Neurology division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil; Graduate Program in Medicine: Medical Sciences, and Internal Medicine Department; Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Ana Lucila Moreira
- Neurology Department, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Fernando Kok
- Neurogenetics Outpatient Service, Neurology Department, Hospital das Clínicas da Universidade de São Paulo, São Paulo, Brazil and Mendelics, São Paulo, Brazil
| | - Alessandro Introna
- Neurology Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari 'Aldo Moro', Bari, Italy
| | - Giancarlo Logroscino
- Neurology Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari 'Aldo Moro', Bari, Italy
- Department of Clinical Research in Neurology, Center for Neurodegenerative Diseases and the Aging Brain, University of Bari at 'Pia Fondazione Card G. Panico' Hospital Tricase (Le), Bari, Italy
| | - Christopher Grunseich
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Alec R Nickolls
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Naemeh Pourshafie
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Sarah B Neuhaus
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Dimah Saade
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Andrea Gangfuß
- Department of Paediatric Neurology, Center for Neuromuscular Disorders in Children and Adolescents, University Clinic Essen, University of Duisburg-Essen, Duisburg-Essen, Germany
| | - Heike Kölbel
- Department of Paediatric Neurology, Center for Neuromuscular Disorders in Children and Adolescents, University Clinic Essen, University of Duisburg-Essen, Duisburg-Essen, Germany
| | - Zoe Piccus
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Claire E Le Pichon
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Chiara Fiorillo
- Paediatric Neurology and Muscular Diseases Unit, G. Gaslini Institute and Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health University of Genoa, Genoa, Italy
| | - Cindy V Ly
- Department of Neurology, Washington University in Saint Louis School of Medicine, Saint Louis, MO, USA
| | - Ana Töpf
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Lauren Brady
- Division of Neuromuscular & Neurometabolic Disorders, Department of Paediatrics, McMaster University, Hamilton Health Sciences Centre, Hamilton, Ontario, Canada
| | - Sabine Specht
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Aliza Zidell
- Center for Genetic and Genomic Medicine, Hackensack University Medical Center, Hackensack, NJ, USA
| | - Helio Pedro
- Center for Genetic and Genomic Medicine, Hackensack University Medical Center, Hackensack Meridian School of Medicine, Hackensack, NJ, USA
| | - Eric Mittelmann
- Department of Neurology, Hereditary Neuropathy Foundation Center of Excellence, Neuroscience Institute, Hackensack University Medical Center, Hackensack Meridian School of Medicine, Hackensack, NJ, USA
| | - Florian P Thomas
- Department of Neurology, Hereditary Neuropathy Foundation Center of Excellence, Neuroscience Institute, Hackensack University Medical Center, Hackensack Meridian School of Medicine, Hackensack, NJ, USA
| | - Katherine R Chao
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Chamindra G Konersman
- Department of Neurosciences, University of California, San Diego, San Diego, CA, USA
| | | | | | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Anne M Connolly
- Department of Paediatrics, Neurology Division, Nationwide Children's Hospital, Ohio State University, Columbus, OH, USA
| | - Ulrike Schara
- Department of Paediatric Neurology, Center for Neuromuscular Disorders in Children and Adolescents, University Clinic Essen, University of Duisburg-Essen, Duisburg-Essen, Germany
| | - Andreas Roos
- Department of Paediatric Neurology, Center for Neuromuscular Disorders in Children and Adolescents, University Clinic Essen, University of Duisburg-Essen, Duisburg-Essen, Germany
| | - Mark Tarnopolsky
- Division of Neuromuscular & Neurometabolic Disorders, Department of Paediatrics, McMaster University, Hamilton Health Sciences Centre, Hamilton, Ontario, Canada
| | - Ahmet Höke
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Robert H Brown
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Chia-Hsueh Lee
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Thorsten Hornemann
- Institute of Clinical Chemistry, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Teresa M Dunn
- Department of Biochemistry and Molecular Biology, Uniformed Services University of Health Sciences, Bethesda, MD, USA.
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
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29
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Pham AK, Miller M, Rosenthal P, Das S, Weng N, Jang S, Kurten RC, Badrani J, Doherty TA, Oliver B, Broide DH. ORMDL3 expression in ASM regulates hypertrophy, hyperplasia via TPM1 and TPM4, and contractility. JCI Insight 2021; 6:136911. [PMID: 33661765 PMCID: PMC8119187 DOI: 10.1172/jci.insight.136911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 02/26/2021] [Indexed: 12/21/2022] Open
Abstract
ORM1-like 3 (ORMDL3) has strong genetic linkage to childhood onset asthma. To determine whether ORMDL3 selective expression in airway smooth muscle (ASM) influences ASM function, we used Cre-loxP techniques to generate transgenic mice (hORMDL3Myh11eGFP-cre), which express human ORMDL3 selectively in smooth muscle cells. In vitro studies of ASM cells isolated from the bronchi of hORMDL3Myh11eGFP-cre mice demonstrated that they developed hypertrophy (quantitated by FACS and image analysis), developed hyperplasia (assessed by BrdU incorporation), and expressed increased levels of tropomysin proteins TPM1 and TPM4. siRNA knockdown of TPM1 or TPM4 demonstrated their importance to ORMDL3-mediated ASM proliferation but not hypertrophy. In addition, ASM derived from hORMDL3Myh11eGFP-cre mice had increased contractility to histamine in vitro, which was associated with increased levels of intracellular Ca2+; increased cell surface membrane Orai1 Ca2+ channels, which mediate influx of Ca2+ into the cytoplasm; and increased expression of ASM contractile genes sarco/endoplasmic reticulum Ca2+ ATPase 2b and smooth muscle 22. In vivo studies of hORMDL3Myh11eGFP-cre mice demonstrated that they had a spontaneous increase in ASM and airway hyperreactivity (AHR). ORMDL3 expression in ASM thus induces changes in ASM (hypertrophy, hyperplasia, increased contractility), which may explain the contribution of ORMDL3 to the development of AHR in childhood onset asthma, which is highly linked to ORMDL3 on chromosome 17q12-21.
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Affiliation(s)
- Alexa K. Pham
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Marina Miller
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Peter Rosenthal
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sudipta Das
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Ning Weng
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sunghoon Jang
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Richard C. Kurten
- Department of Pediatrics, Arkansas Children’s Research Institute, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Jana Badrani
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Taylor A. Doherty
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- Veterans Affairs San Diego Health Care System, La Jolla, California, USA
| | - Brian Oliver
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
| | - David H. Broide
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
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Structural insights into the regulation of human serine palmitoyltransferase complexes. Nat Struct Mol Biol 2021; 28:240-248. [PMID: 33558761 PMCID: PMC9812531 DOI: 10.1038/s41594-020-00551-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/16/2020] [Indexed: 01/31/2023]
Abstract
Sphingolipids are essential lipids in eukaryotic membranes. In humans, the first and rate-limiting step of sphingolipid synthesis is catalyzed by the serine palmitoyltransferase holocomplex, which consists of catalytic components (SPTLC1 and SPTLC2) and regulatory components (ssSPTa and ORMDL3). However, the assembly, substrate processing and regulation of the complex are unclear. Here, we present 8 cryo-electron microscopy structures of the human serine palmitoyltransferase holocomplex in various functional states at resolutions of 2.6-3.4 Å. The structures reveal not only how catalytic components recognize the substrate, but also how regulatory components modulate the substrate-binding tunnel to control enzyme activity: ssSPTa engages SPTLC2 and shapes the tunnel to determine substrate specificity. ORMDL3 blocks the tunnel and competes with substrate binding through its amino terminus. These findings provide mechanistic insights into sphingolipid biogenesis governed by the serine palmitoyltransferase complex.
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Structural insights into the assembly and substrate selectivity of human SPT-ORMDL3 complex. Nat Struct Mol Biol 2021; 28:249-257. [PMID: 33558762 DOI: 10.1038/s41594-020-00553-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/16/2020] [Indexed: 01/31/2023]
Abstract
Human serine palmitoyltransferase (SPT) complex catalyzes the initial and rate-limiting step in the de novo biosynthesis of all sphingolipids. ORMDLs regulate SPT function, with human ORMDL3 being related to asthma. Here we report three high-resolution cryo-EM structures: the human SPT complex, composed of SPTLC1, SPTLC2 and SPTssa; the SPT-ORMDL3 complex; and the SPT-ORMDL3 complex bound to two substrates, PLP-L-serine (PLS) and a non-reactive palmitoyl-CoA analogue. SPTLC1 and SPTLC2 form a dimer of heterodimers as the catalytic core. SPTssa participates in acyl-CoA coordination, thereby stimulating the SPT activity and regulating the substrate selectivity. ORMDL3 is located in the center of the complex, serving to stabilize the SPT assembly. Our structural and biochemical analyses provide a molecular basis for the assembly and substrate selectivity of the SPT and SPT-ORMDL3 complexes, and lay a foundation for mechanistic understanding of sphingolipid homeostasis and for related therapeutic drug development.
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Bugajev V, Halova I, Demkova L, Cernohouzova S, Vavrova P, Mrkacek M, Utekal P, Draberova L, Kuchar L, Schuster B, Draber P. ORMDL2 Deficiency Potentiates the ORMDL3-Dependent Changes in Mast Cell Signaling. Front Immunol 2021; 11:591975. [PMID: 33643282 PMCID: PMC7905224 DOI: 10.3389/fimmu.2020.591975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/29/2020] [Indexed: 12/24/2022] Open
Abstract
The systemic anaphylactic reaction is a life-threatening allergic response initiated by activated mast cells. Sphingolipids are an essential player in the development and attenuation of this response. De novo synthesis of sphingolipids in mammalian cells is inhibited by the family of three ORMDL proteins (ORMDL1, 2, and 3). However, the cell and tissue-specific functions of ORMDL proteins in mast cell signaling are poorly understood. This study aimed to determine cross-talk of ORMDL2 and ORMDL3 proteins in IgE-mediated responses. To this end, we prepared mice with whole-body knockout (KO) of Ormdl2 and/or Ormdl3 genes and studied their role in mast cell-dependent activation events in vitro and in vivo. We found that the absence of ORMDL3 in bone marrow-derived mast cells (BMMCs) increased the levels of cellular sphingolipids. Such an increase was further raised by simultaneous ORMDL2 deficiency, which alone had no effect on sphingolipid levels. Cells with double ORMDL2 and ORMDL3 KO exhibited increased intracellular levels of sphingosine-1-phosphate (S1P). Furthermore, we found that concurrent ORMDL2 and ORMDL3 deficiency increased IκB-α phosphorylation, degranulation, and production of IL-4, IL-6, and TNF-α cytokines in antigen-activated mast cells. Interestingly, the chemotaxis towards antigen was increased in all mutant cell types analyzed. Experiments in vivo showed that passive cutaneous anaphylaxis (PCA), which is initiated by mast cell activation, was increased only in ORMDL2,3 double KO mice, supporting our in vitro observations with mast cells. On the other hand, ORMDL3 KO and ORMDL2,3 double KO mice showed faster recovery from passive systemic anaphylaxis, which could be mediated by increased levels of blood S1P presented in such mice. Our findings demonstrate that Ormdl2 deficiency potentiates the ORMDL3-dependent changes in mast cell signaling.
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Affiliation(s)
- Viktor Bugajev
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Ivana Halova
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Livia Demkova
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Sara Cernohouzova
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Petra Vavrova
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Michal Mrkacek
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Pavol Utekal
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Lubica Draberova
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Ladislav Kuchar
- Research Unit for Rare Diseases, Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Björn Schuster
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Petr Draber
- Department of Signal Transduction, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
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Berlansky S, Humer C, Sallinger M, Frischauf I. More Than Just Simple Interaction between STIM and Orai Proteins: CRAC Channel Function Enabled by a Network of Interactions with Regulatory Proteins. Int J Mol Sci 2021; 22:E471. [PMID: 33466526 PMCID: PMC7796502 DOI: 10.3390/ijms22010471] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 12/29/2020] [Accepted: 12/29/2020] [Indexed: 12/27/2022] Open
Abstract
The calcium-release-activated calcium (CRAC) channel, activated by the release of Ca2+ from the endoplasmic reticulum (ER), is critical for Ca2+ homeostasis and active signal transduction in a plethora of cell types. Spurred by the long-sought decryption of the molecular nature of the CRAC channel, considerable scientific effort has been devoted to gaining insights into functional and structural mechanisms underlying this signalling cascade. Key players in CRAC channel function are the Stromal interaction molecule 1 (STIM1) and Orai1. STIM1 proteins span through the membrane of the ER, are competent in sensing luminal Ca2+ concentration, and in turn, are responsible for relaying the signal of Ca2+ store-depletion to pore-forming Orai1 proteins in the plasma membrane. A direct interaction of STIM1 and Orai1 allows for the re-entry of Ca2+ from the extracellular space. Although much is already known about the structure, function, and interaction of STIM1 and Orai1, there is growing evidence that CRAC under physiological conditions is dependent on additional proteins to function properly. Several auxiliary proteins have been shown to regulate CRAC channel activity by means of direct interactions with STIM1 and/or Orai1, promoting or hindering Ca2+ influx in a mechanistically diverse manner. Various proteins have also been identified to exert a modulatory role on the CRAC signalling cascade although inherently lacking an affinity for both STIM1 and Orai1. Apart from ubiquitously expressed representatives, a subset of such regulatory mechanisms seems to allow for a cell-type-specific control of CRAC channel function, considering the rather restricted expression patterns of the specific proteins. Given the high functional and clinical relevance of both generic and cell-type-specific interacting networks, the following review shall provide a comprehensive summary of regulators of the multilayered CRAC channel signalling cascade. It also includes proteins expressed in a narrow spectrum of cells and tissues that are often disregarded in other reviews of similar topics.
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Affiliation(s)
| | | | | | - Irene Frischauf
- Institute of Biophysics, Johannes Kepler University, 4020 Linz, Austria; (S.B.); (C.H.); (M.S.)
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ORMDL3/GSDMB genotype as a risk factor for early-onset adult asthma is linked to total serum IgE levels but not to allergic sensitization. Allergol Int 2021; 70:55-60. [PMID: 32444308 DOI: 10.1016/j.alit.2020.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/03/2020] [Accepted: 04/19/2020] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND An orosomucoid-like 3 (ORMDL3)/gasdermin B (GSDMB) gene locus on chromosome 17q is consistently associated with childhood-onset asthma, which is highly atopic. As some evidence suggests the relationship between asthma and allergic sensitization reflects asthma patient susceptibility to augmented IgE responses driven by common environmental allergens rather than an increased asthma risk after allergen exposure, we aimed to determine any relationships between this locus region and childhood-onset adult asthma with regard to serum total IgE levels or allergic sensitization. METHODS We conducted a case-control association study using three independent Japanese populations (3869 total adults) and analyzed the ORs for association of rs7216389, an expression quantitative trait locus for ORMDL3/GSDMB, with adult asthma according to onset age. Additionally, associations between the rs7216389 genotype and total serum IgE levels or allergic sensitization was examined. RESULTS Rs7216389 was associated with both childhood-onset adult asthma (OR for asthmatic patients afflicted at the age of 10 years or younger = 1.61, p = 0.00021) and asthmatic patients with higher levels of total serum IgE (OR for asthmatic patients with IgE ≥1000IU/mL = 1.55, p = 0.0033). In both healthy controls and in the combined healthy and asthmatic individuals, rs7216389 was correlated with increased total serum IgE levels (p < 0.0005), but not allergic sensitization (p > 0.1). CONCLUSIONS ORMDL3/GSDMB is an important susceptibility gene for childhood-onset adult asthma in Japanese populations and this association is linked to elevated total serum IgE levels but not to allergic sensitization.
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Expression Patterns and Prognostic Values of ORMDL1 in Different Cancers. BIOMED RESEARCH INTERNATIONAL 2020; 2020:5178397. [PMID: 33145351 PMCID: PMC7596526 DOI: 10.1155/2020/5178397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 08/03/2020] [Accepted: 09/15/2020] [Indexed: 01/13/2023]
Abstract
The mammalian orosomucoid-like gene family (ORMDL), containing ORMDL1, ORMDL2, and ORMDL3, is the important regulator of sphingolipid metabolism, which is relevant to cell growth, proliferation, migration, and invasion. Since the role of ORMDL1 in cancers remained unclear, the main purpose of our study was to explore the expression patterns and prognostic values of ORMDL1 in different tumors, especially in cholangiocarcinoma (CHOL), lymphoid neoplasm diffuse large B cell lymphoma (DLBCL), acute myeloid leukemia (LAML), and thymoma (THYM). Bioinformatics tools including GEPIA, CCLE, LinkedOmics, cBioPortal, and TIMER databases were used. As a result, the expression levels of ORMDL1 in tumor tissues and normal tissues varied in different cancers, especially significantly upregulated in CHOL, DLBCL, LAML, and THYM. Moreover, ORMDL1 mRNA was also highly expressed in cell lines of DLBCL and LAML. Further studies showed that ORMDL1 overexpression was associated with poor prognosis in DLBCL, but not significant in CHOL, LAML, and THYM. Consistently, there were genetic alterations of ORMDL1 in DLBCL, and patients with genetic alterations indicated worse survival. Coexpressed genes and related biological events with ORMDL1 in DLBCL were found via LinkedOmics, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The relationship between ORMDL1 and cancer immune cells was investigated, and ORMDL1 expression was positively correlated with infiltrating levels of B cells. In conclusion, ORMDL1 is suggested to be a tumorigenic factor and considered as the potential therapeutic target and prognostic biomarker in DLBCL.
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Li Y, Li X, Zhou W, Yu Q, Lu Y. ORMDL3 modulates airway epithelial cell repair in children with asthma under glucocorticoid treatment via regulating IL-33. Pulm Pharmacol Ther 2020; 64:101963. [PMID: 33035699 DOI: 10.1016/j.pupt.2020.101963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/30/2020] [Indexed: 11/19/2022]
Abstract
BACKGROUND Study found that glucocorticoids, as first-line treatments for asthma, fails to prevent asthma recurrence. Orosomucoid-like (ORMDL) 3 is associated to childhood asthma onset and involved in the inflammation and repair of airway epithelium. We explored the functional role of ORMDL3 in glucocorticoid treatment for childhood asthma. METHODS Mice were sensitized with Ovalbumin (OVA) and treated with Dexamethasone (Dex), followed by OVA challenge to establish a mouse model of asthma. Histopathological changes in lung tissues were observed by hematoxylin-eosin and masson staining. Human bronchial epithelial (16HBE-14°) cells were transfected with ORMDL3 overexpression plasmid and siRNA-interleukin (IL)-33 alone or in combination, followed by Dex. Cell viability was measured by MTT assay. Cell migration was evaluated by wound healing assay. The expressions of E-cadherin and Vimentin and the activation of NF-κB and MAPK/ERK in 16HBE-14° cells were assessed by Western blot. The expressions of ORMDL3 and IL-33 in lung tissues and 16HBE-14° cells were analyzed by qRT-PCR or Western blot. RESULTS Dex treatment alleviated the histopathological abnormality and reversed the overexpressions of ORMDL3 and IL-33 in the lung tissues of asthmatic mice. Overexpressed ORMDL3 enhanced migration and viability, decreased E-cadherin level, increased the levels of IL-33 and Vimentin, and promoted the phosphorylation of NF-κB and MAPK/ERK in Dex-treated 16HBE-14° cells, thus reversing the effect of Dex treatment. However, siRNA-IL-33 inhibited viability and migration, increased E-cadherin level, decreased Vimentin level, and suppressed the phosphorylation of NF-κB and MAPK/ERK, thus reversing the effect of overexpressed ORMDL3 in Dex-treated 16HBE-14° cells. CONCLUSION ORMDL3 overexpression helped airway epithelial cellrepairin asthma via regulating IL-33 expression.
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Affiliation(s)
- Yaqin Li
- Department of Pediatrics, South Campus, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No.2000, Jiangyue Road, Pujiang, Minhang District, Shanghai, 201112, China
| | - Xiaoyan Li
- Department of Pediatrics, South Campus, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No.2000, Jiangyue Road, Pujiang, Minhang District, Shanghai, 201112, China
| | - Wenjing Zhou
- Department of Pediatrics, South Campus, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No.2000, Jiangyue Road, Pujiang, Minhang District, Shanghai, 201112, China
| | - Qing Yu
- Department of Pediatrics, South Campus, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No.2000, Jiangyue Road, Pujiang, Minhang District, Shanghai, 201112, China
| | - Yanming Lu
- Department of Pediatrics, South Campus, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No.2000, Jiangyue Road, Pujiang, Minhang District, Shanghai, 201112, China.
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Pant DC, Aguilera-Albesa S, Pujol A. Ceramide signalling in inherited and multifactorial brain metabolic diseases. Neurobiol Dis 2020; 143:105014. [PMID: 32653675 DOI: 10.1016/j.nbd.2020.105014] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/13/2020] [Accepted: 07/07/2020] [Indexed: 12/14/2022] Open
Abstract
In recent years, research on sphingolipids, particularly ceramides, has attracted increased attention, revealing the important roles and many functions of these molecules in several human neurological disorders. The nervous system is enriched with important classes of sphingolipids, e.g., ceramide and its derivatives, which compose the major portion of this group, particularly in the form of myelin. Ceramides have also emerged as important nodes for lipid signalling, both inside the cell and between cells. Until recently, knowledge about ceramides in the nervous system was limited, but currently, multiple links between ceramide signalling and neurological diseases have been reported. Alterations in the regulation of ceramide pathobiology have been shown to influence the risk of developing neurometabolic diseases. Thus, these molecules are critically important in the maintenance and development of the nervous system and are culprits or major contributors to the development of brain disorders, either inherited or multifactorial. In the present review, we highlight the critical role of ceramide signalling in several different neurological disorders as well as the effects of their perturbations and discuss how this emerging class of bioactive sphingolipids has attracted interest in the field of neurological diseases.
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Affiliation(s)
- Devesh C Pant
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA
| | - Sergio Aguilera-Albesa
- Pediatric Neurology Unit, Department of Pediatrics, Navarra Health Service Hospital, Irunlarrea 4, 310620 Pamplona, Spain; Navarrabiomed-Miguel Servet Research Foundation, Pamplona, Spain
| | - Aurora Pujol
- Neurometabolic Diseases Laboratory, IDIBELL, Hospital Duran i Reynals, Gran Via 199, 08908, L'Hospitalet de Llobregat, Barcelona, Spain; Catalan Institution of Research and Advanced Studies (ICREA), Barcelona, Catalonia, Spain; Center for Biomedical Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain.
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Lee H, Fenske RJ, Akcan T, Domask E, Davis DB, Kimple ME, Engin F. Differential Expression of Ormdl Genes in the Islets of Mice and Humans with Obesity. iScience 2020; 23:101324. [PMID: 32659722 PMCID: PMC7358727 DOI: 10.1016/j.isci.2020.101324] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 05/05/2020] [Accepted: 06/25/2020] [Indexed: 12/28/2022] Open
Abstract
The orosomucoid-like (Ormdl) proteins play a critical role in sphingolipid homeostasis, inflammation, and ER stress, all of which are associated with obesity and βcell dysfunction. However, their roles in β cells and obesity remain unknown. Here, we show that islets from overweight/obese human donors displayed marginally reduced ORMDL1-2 expression, whereas ORMDL3 expression was significantly downregulated compared with islets from lean donors. In contrast, Ormdl3 was substantially upregulated in the islets of leptin-deficient obese (ob/ob) mice compared with lean mice. Treatment of ob/ob mice and their islets with leptin markedly reduced islet Ormld3 expression. Ormdl3 knockdown in a β cell line induced expression of pro-apoptotic markers, which was rescued by ceramide synthase inhibitor fumonisin B1. Our results reveal differential expression of Ormdl3 in the islets of a mouse model and humans with obesity, highlight the potential effect of leptin in this differential regulation, and suggest a role for Ormdl3 in β cell apoptosis. Islets of overweight/obese human donors display markedly reduced ORMDL3 expression Ormdl3 expression was significantly upregulated in the islets of ob/ob mice Leptin treatment markedly reduced Ormld3 expression in the islets of ob/ob mice Fumonisin B1 restores increased apoptotic marker levels induced by Ormdl3 silencing
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Affiliation(s)
- Hugo Lee
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53706, USA
| | - Rachel J Fenske
- Interdepartmental Graduate Program in Nutritional Sciences, Madison, WI 53706, USA; Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53705, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA
| | - Tugce Akcan
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53706, USA
| | - Elliot Domask
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53706, USA
| | - Dawn B Davis
- Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53705, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA
| | - Michelle E Kimple
- Interdepartmental Graduate Program in Nutritional Sciences, Madison, WI 53706, USA; Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53705, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA; Department of Cell and Regenerative Biology, Madison, WI 53705, USA; Department of Academic Affairs, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Feyza Engin
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53706, USA; Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Wisconsin-Madison, School of Medicine and Public Health, WI 53705, USA.
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Subunit composition of the mammalian serine-palmitoyltransferase defines the spectrum of straight and methyl-branched long-chain bases. Proc Natl Acad Sci U S A 2020; 117:15591-15598. [PMID: 32576697 DOI: 10.1073/pnas.2002391117] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Sphingolipids (SLs) are chemically diverse lipids that have important structural and signaling functions within mammalian cells. SLs are commonly defined by the presence of a long-chain base (LCB) that is normally formed by the conjugation of l-serine and palmitoyl-CoA. This pyridoxal 5-phosphate (PLP)-dependent reaction is mediated by the enzyme serine-palmitoyltransferase (SPT). However, SPT can also metabolize other acyl-CoAs, in the range of C14 to C18, forming a variety of LCBs that differ by structure and function. Mammalian SPT consists of three core subunits: SPTLC1, SPTLC2, and SPTLC3. Whereas SPTLC1 and SPTLC2 are ubiquitously expressed, SPTLC3 expression is restricted to certain tissues only. The influence of the individual subunits on enzyme activity is not clear. Using cell models deficient in SPTLC1, SPTLC2, and SPTLC3, we investigated the role of each subunit on enzyme activity and the LCB product spectrum. We showed that SPTLC1 is essential for activity, whereas SPTLC2 and SPTLC3 are partly redundant but differ in their enzymatic properties. SPTLC1 in combination with SPTLC2 specifically formed C18, C19, and C20 LCBs while the combination of SPTLC1 and SPTLC3 yielded a broader product spectrum. We identified anteiso-branched-C18 SO (meC18SO) as the primary product of the SPTLC3 reaction. The meC18SO was synthesized from anteiso-methyl-palmitate, in turn synthesized from a precursor metabolite generated in the isoleucine catabolic pathway. The meC18SO is metabolized to ceramides and complex SLs and is a constituent of human low- and high-density lipoproteins.
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Clarke BA, Majumder S, Zhu H, Lee YT, Kono M, Li C, Khanna C, Blain H, Schwartz R, Huso VL, Byrnes C, Tuymetova G, Dunn TM, Allende ML, Proia RL. The Ormdl genes regulate the sphingolipid synthesis pathway to ensure proper myelination and neurologic function in mice. eLife 2019; 8:51067. [PMID: 31880535 PMCID: PMC6934382 DOI: 10.7554/elife.51067] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/09/2019] [Indexed: 12/23/2022] Open
Abstract
Sphingolipids are membrane and bioactive lipids that are required for many aspects of normal mammalian development and physiology. However, the importance of the regulatory mechanisms that control sphingolipid levels in these processes is not well understood. The mammalian ORMDL proteins (ORMDL1, 2 and 3) mediate feedback inhibition of the de novo synthesis pathway of sphingolipids by inhibiting serine palmitoyl transferase in response to elevated ceramide levels. To understand the function of ORMDL proteins in vivo, we studied mouse knockouts (KOs) of the Ormdl genes. We found that Ormdl1 and Ormdl3 function redundantly to suppress the levels of bioactive sphingolipid metabolites during myelination of the sciatic nerve. Without proper ORMDL-mediated regulation of sphingolipid synthesis, severe dysmyelination results. Our data indicate that the Ormdls function to restrain sphingolipid metabolism in order to limit levels of dangerous metabolic intermediates that can interfere with essential physiological processes such as myelination.
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Affiliation(s)
- Benjamin A Clarke
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Saurav Majumder
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Hongling Zhu
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Y Terry Lee
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Mari Kono
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Cuiling Li
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Caroline Khanna
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Hailey Blain
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Ronit Schwartz
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Vienna L Huso
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Colleen Byrnes
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Galina Tuymetova
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Teresa M Dunn
- Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, United States
| | - Maria L Allende
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
| | - Richard L Proia
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, United States
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Abstract
Long chain base (LCB) is a unique building block found in sphingolipids. The initial step of LCB biosynthesis stems from serine:palmitoyl-CoA transferase enzyme, producing 3-ketodihydrosphingosine with multiple regulatory proteins including small subunit SPT a/b and orosomucoid-like protein1-3. 3-Ketodihydrosphingosine reductase and sphingolipid Δ4-desaturase, both of them poorly characterized mammalian enzymes, play key roles for neurological homeostasis based on their pathogenic mutation in humans. Ceramide synthase in mammals has six isoforms with distinct phenotype in each knockout mouse. In plants and fungi, sphingolipids also contain phytosphingosine due to sphingolipid C4-hydroxylase. In contrast to previous notion that dietary intake might be its major route in animals, emerging evidences suggested that phytosphingosine biosynthesis does occur in some tissues such as the skin by mammalian C4-hydroxylase activity of the DEGS2 gene. This short review summarizes LCB biosynthesis with their associating metabolic pathways in animals, plants and fungi. Sphingolipid is a group of lipids that contains a unique building block known as long chain base (LCB). LCB is susceptible to various biosynthetic reactions such as unsaturation, hydroxylation and methylation. A failure of these enzymatic reactions leads to the pathogenesis in humans with an elevation of LCB-derived specific biomarkers. Herein, we summarized emerging evidences in mammalian LCB biosynthesis in sphingolipids. Some unique metabolic pathways in plants and fungi were also discussed.
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Wang X, Cao X, Wen Y, Ma Y, Elnour IE, Huang Y, Lan X, Chaogetu B, Hu L, Chen H. Associations of ORMDL1 gene copy number variations with growth traits in four Chinese sheep breeds. Arch Anim Breed 2019; 62:571-578. [PMID: 31807669 PMCID: PMC6853131 DOI: 10.5194/aab-62-571-2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 09/26/2019] [Indexed: 11/11/2022] Open
Abstract
Copy number variations (CNVs) are gains and losses of genomic sequence of more
than 50 bp between two individuals of a species. Also, CNV is considered to be one
of the main elements affecting the phenotypic diversity and evolutionary
adaptation of animals. ORMDL sphingolipid biosynthesis regulator 1
(ORMDL1) is a protein-coding gene associated with diseases and development. In our
study, the polymorphism of ORMDL1 gene copy numbers in four Chinese sheep breeds
(abbreviated CK, HU, STH, and LTH) was detected. In addition, we analyzed the
transcriptional expression level of ORMDL1 gene in different tissues of sheep and
examined the association of ORMDL1 CNV with growth traits. The statistical
analysis revealed that ORMDL1 CNV was remarkably correlated with body height,
heart girth, and circumference of cannon bone in HU sheep (P<0.05),
and there are significant effects on body weight, body height, body length,
chest depth, and height of hip cross in STH sheep (P<0.05). In
conclusion, our results provide a basis for the relationship between CNV of
ORMDL1 gene and sheep growth traits, suggesting that ORMDL1 CNV may be considered a promising marker for the molecular breeding of Chinese sheep.
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Affiliation(s)
- Xiaogang Wang
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiukai Cao
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yifan Wen
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yilei Ma
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ibrahim Elsaeid Elnour
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yongzhen Huang
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xianyong Lan
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Buren Chaogetu
- Animal Disease Control Center of Haixi Mongolian and Tibetan Autonomous Prefecture, Delingha, Qinghai 817000, China
| | - Linyong Hu
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, 810001, China
| | - Hong Chen
- Key laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
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Cheng Q, Shang Y, Huang W, Zhang Q, Li X, Zhou Q. p300 mediates the histone acetylation of ORMDL3 to affect airway inflammation and remodeling in asthma. Int Immunopharmacol 2019; 76:105885. [PMID: 31536903 DOI: 10.1016/j.intimp.2019.105885] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 08/20/2019] [Accepted: 09/05/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND Bronchial asthma is affected by both environmental and genetic factors. The orosomucoid 1-like protein 3 (ORMDL3) gene is related to childhood asthma and is involved in airway inflammation and airway remodeling. The ORMDL3 promoter contains binding sites for the histone acetylase p300. Gene expression can be affected by epigenetic modifications. This study aimed to investigate whether the p300-mediated histone acetylation (HAT) of ORMDL3 gene affects airway inflammation and remodeling in asthma. METHODS 16HBE14o- cells were transfected with various concentrations of a wild-type p300 plasmid or p300HAT-deletion plasmids. A dual luciferase reporter assay was used to examine the effect of p300-mediated HAT on the ORMDL3 promoter. Thirty BALB/c mice were randomly divided into a control group, an ovalbumin (OVA)-induced asthma group and an asthma + C646 (a selective inhibitor of p300) group. Noninvasive lung function tests were conducted to examine airway hyperreactivity (AHR) in the different groups. HE and Masson's trichrome staining was performed to examine airway remodeling and inflammation. Immunohistochemistry, western blotting and real-time PCR were used to analyze ORMDL3 expression in lung tissues. ELISA and western blotting were used to evaluate the HAT status in lung tissue. The ChIP assay was used to determine the relationship of the ORMDL3 promoter to p300 or acetylated histone H3 (aceH3). RESULTS p300 activated transcription from the ORMDL3 promoter, resulting in an increase in endogenous ORMDL3 mRNA levels. ORMDL3 promoter activity was reduced when the HAT activity of p300 was lost. ORMDL3 expression was elevated, and HAT activity was high in the lung tissues of asthmatic mice. p300 and aceH3 bound to the promoter region of ORMDL3. In the asthma group, the amounts of p300 and aceH3 recruited to the ORMDL3 promoter were increased. C646 inhibited p300 expression and reduced HAT activity and aceH3 levels in asthmatic mice, thereby reducing ORMDL3 expression and relieving AHR and airway remodeling. CONCLUSION p300-mediated HAT modulates the expression of the asthma susceptibility gene ORMDL3, thereby improving the process of airway inflammation and remodeling in asthma.
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Affiliation(s)
- Qi Cheng
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China.
| | - Yunxiao Shang
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China.
| | - Wanjie Huang
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China
| | - Qinzhen Zhang
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China
| | - Xiang Li
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China
| | - Qianlan Zhou
- Pediatric Pulmonology Department, Shengjing Hospital of China Medical University, 36th Sanhao Street, Heping District, Shenyang 110004, PR China
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Zahumensky J, Malinsky J. Role of MCC/Eisosome in Fungal Lipid Homeostasis. Biomolecules 2019; 9:E305. [PMID: 31349700 PMCID: PMC6723945 DOI: 10.3390/biom9080305] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022] Open
Abstract
One of the best characterized fungal membrane microdomains is the MCC/eisosome. The MCC (membrane compartment of Can1) is an evolutionarily conserved ergosterol-rich plasma membrane domain. It is stabilized on its cytosolic face by the eisosome, a hemitubular protein complex composed of Bin/Amphiphysin/Rvs (BAR) domain-containing Pil1 and Lsp1. These two proteins bind directly to phosphatidylinositol 4,5-bisphosphate and promote the typical furrow-like shape of the microdomain, with highly curved edges and bottom. While some proteins display stable localization in the MCC/eisosome, others enter or leave it under particular conditions, such as misbalance in membrane lipid composition, changes in membrane tension, or availability of specific nutrients. These findings reveal that the MCC/eisosome, a plasma membrane microdomain with distinct morphology and lipid composition, acts as a multifaceted regulator of various cellular processes including metabolic pathways, cellular morphogenesis, signalling cascades, and mRNA decay. In this minireview, we focus on the MCC/eisosome's proposed role in the regulation of lipid metabolism. While the molecular mechanisms of the MCC/eisosome function are not completely understood, the idea of intracellular processes being regulated at the plasma membrane, the foremost barrier exposed to environmental challenges, is truly exciting.
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Affiliation(s)
- Jakub Zahumensky
- Department of Microscopy, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic
| | - Jan Malinsky
- Department of Microscopy, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
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Debeuf N, Zhakupova A, Steiner R, Van Gassen S, Deswarte K, Fayazpour F, Van Moorleghem J, Vergote K, Pavie B, Lemeire K, Hammad H, Hornemann T, Janssens S, Lambrecht BN. The ORMDL3 asthma susceptibility gene regulates systemic ceramide levels without altering key asthma features in mice. J Allergy Clin Immunol 2019; 144:1648-1659.e9. [PMID: 31330218 DOI: 10.1016/j.jaci.2019.06.041] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 06/27/2019] [Accepted: 06/28/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Genome-wide association studies in asthma have repeatedly identified single nucleotide polymorphisms in the ORM (yeast)-like protein isoform 3 (ORMDL3) gene across different populations. Although the ORM homologues in yeast are well-known inhibitors of sphingolipid synthesis, it is still unclear whether and how mammalian ORMDL3 regulates sphingolipid metabolism and whether altered sphingolipid synthesis would be causally related to asthma risk. OBJECTIVE We sought to examine the in vivo role of ORMDL3 in sphingolipid metabolism and allergic asthma. METHODS Ormdl3-LacZ reporter mice, gene-deficient Ormdl3-/- mice, and overexpressing Ormdl3Tg/wt mice were exposed to physiologically relevant aeroallergens, such as house dust mite (HDM) or Alternaria alternata, to induce experimental asthma. Mass spectrometry-based sphingolipidomics were performed, and airway eosinophilia, TH2 cytokine production, immunoglobulin synthesis, airway remodeling, and bronchial hyperreactivity were measured. RESULTS HDM challenge significantly increased levels of total sphingolipids in the lungs of HDM-sensitized mice compared with those in control mice. In Ormdl3Tg/wt mice the allergen-induced increase in lung ceramide levels was significantly reduced, whereas total sphingolipid levels were not affected. Conversely, in liver and serum, levels of total sphingolipids, including ceramides, were increased in Ormdl3-/- mice, whereas they were decreased in Ormdl3Tg/wt mice. This difference was independent of allergen exposure. Despite these changes, all features of asthma were identical between wild-type, Ormdl3Tg/wt, and Ormdl3-/- mice across several models of experimental asthma. CONCLUSION ORMDL3 regulates systemic ceramide levels, but genetically interfering with Ormdl3 expression does not result in altered experimental asthma.
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Affiliation(s)
- Nincy Debeuf
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Assem Zhakupova
- Institute of Clinical Chemistry, University and University Hospital Zurich, Zurich, Switzerland
| | - Regula Steiner
- Institute of Clinical Chemistry, University and University Hospital Zurich, Zurich, Switzerland
| | - Sofie Van Gassen
- Data Mining and Modeling for Biomedicine, VIB Center for Inflammation Research, Ghent, Belgium; Department of Applied Mathematics, Computer Science and Statistics, Ghent University, Ghent, Belgium
| | - Kim Deswarte
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Farzaneh Fayazpour
- Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium; Laboratory for ER Stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
| | - Justine Van Moorleghem
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Karl Vergote
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Benjamin Pavie
- VIB Bioimaging Core, VIB Center for Inflammation Research, Ghent, Belgium; Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Kelly Lemeire
- Biomedical Molecular Biology, Ghent University, Ghent, Belgium; VIB Center for Inflammation Research, Ghent, Belgium
| | - Hamida Hammad
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Thorsten Hornemann
- Institute of Clinical Chemistry, University and University Hospital Zurich, Zurich, Switzerland
| | - Sophie Janssens
- Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium; Laboratory for ER Stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
| | - Bart N Lambrecht
- Laboratory of Mucosal Immunology and Immunoregulation, VIB Center for Inflammation Research, Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium; Department of Pulmonary Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
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Yang R, Tan M, Xu J, Zhao X. Investigating the regulatory role of ORMDL3 in airway barrier dysfunction using in vivo and in vitro models. Int J Mol Med 2019; 44:535-548. [PMID: 31173170 PMCID: PMC6605285 DOI: 10.3892/ijmm.2019.4233] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 06/04/2019] [Indexed: 02/06/2023] Open
Abstract
The airway epithelium (AE) is the main protective barrier between the host and external environmental factors causing asthma. Allergens or pathogens induce AE dysfunction, including epithelial permeability alteration, trans‑epithelial electrical resistance (TEER) reduction, upregulation of inflammatory mediators and downregulation of junctional complex molecules. Orosomucoid‑like protein isoform 3 (ORMDL3), a gene closely associated with childhood onset asthma, is involved in airway inflammation and remodeling. It was hypothesized that ORMDL3 plays an important role in regulating AE barrier function. In vivo [chronic asthma induced by ovalbumin‑respiratory syncytial virus (OVA‑RSV)] in mice) and in vitro (human bronchial epithelial cells and 16HBE cells) models were used to assess ORMDL3's role in AE function regulation, evaluating paracellular permeability, TEER and the expression levels of junctional complex molecules. The effects of ORMDL3 on the extracellular signal‑regulated protein kinase (ERK) pathway were determined. In mice with OVA‑RSV induced chronic asthma, ORMDL3 and sphingosine kinase 1 (SPHK1) were upregulated whereas the junction related proteins Claudin‑18 and E‑cadherin were downregulated. Overexpression of ORMDL3 resulted in decreased TEER, downregulation of junctional complex molecules and induced epithelial permeability. In contrast, ORMDL3 inhibition showed the opposite effects. In 16HBE cells, ORMDL3 overexpression induced SPHK1 distribution and activity, while SPHK1 inhibition resulted in increased TEER upon administration of an ORMDL3 agonist or ORMDL3 overexpression. In addition, ERK activation occurred downstream of SPHK1 activation in 16HBE cells. High levels of ORMDL3 result in damaged AE barrier function by inducing the SPHK1/ERK pathway.
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Affiliation(s)
- Ruixue Yang
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, P.R. China
| | - Min Tan
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, P.R. China
| | - Jianya Xu
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing, Jiangsu 210023, P.R. China
| | - Xia Zhao
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, P.R. China
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Yang W, Sheng F, Sun B, Fischbach S, Xiao X. The role of ORMDL3/ATF6 in compensated beta cell proliferation during early diabetes. Aging (Albany NY) 2019; 11:2787-2796. [PMID: 31061237 PMCID: PMC6535075 DOI: 10.18632/aging.101949] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/29/2019] [Indexed: 04/12/2023]
Abstract
Endoplasmic reticulum (ER) stress in beta cells induces a signaling network called the unfolded protein response (UPR), which plays a dual role in diabetes. A key regulator of ER-stress and UPR, the orosomucoid 1-like protein 3 (ORMDL3), has been shown to regulate airway remodeling through a major UPR protein, activating transcription factor 6 (ATF6), but the contribution of this regulatory axis to compensatory pancreatic beta cell proliferation in diabetes has not been studied. Here, we detected significantly lower levels of ORMDL3 mRNA in leukocytes of peripheral blood specimens from type 1 diabetes (T1D) children, compared to normal children. Moreover, these ORMDL3 levels in T1D children exhibited further decreases upon follow-up. ORMDL3 levels in islets from NOD mice, a mouse model for T1D in humans, showed a mild increase before diabetes onset, but a gradual decrease subsequently. In high glucose culture, beta cell proliferation, but not apoptosis, was increased by overexpression of ORMDL3 levels, likely mediated by its downstream factor ATF6. Mechanistically, ORMDL3 transcriptionally activated ATF6, which was confirmed in a promoter reporter assay. Together, our data suggest that ORMDL3 may increase beta cell proliferation through ATF6 as an early compensatory change in response to diabetes.
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Affiliation(s)
- Weixia Yang
- Department of Pediatrics, Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Feifei Sheng
- Department of Pediatrics, Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Baolan Sun
- Department of Pediatrics, Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Shane Fischbach
- Department of Surgery, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Xiangwei Xiao
- Department of Surgery, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
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Davis DL, Gable K, Suemitsu J, Dunn TM, Wattenberg BW. The ORMDL/Orm-serine palmitoyltransferase (SPT) complex is directly regulated by ceramide: Reconstitution of SPT regulation in isolated membranes. J Biol Chem 2019; 294:5146-5156. [PMID: 30700557 DOI: 10.1074/jbc.ra118.007291] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 01/25/2019] [Indexed: 01/15/2023] Open
Abstract
Sphingolipids compose a lipid family critical for membrane structure as well as intra- and intercellular signaling. De novo sphingolipid biosynthesis is initiated by the enzyme serine palmitoyltransferase (SPT), which resides in the endoplasmic reticulum (ER) membrane. In both yeast and mammalian species, SPT activity is homeostatically regulated through small ER membrane proteins, the Orms in yeast and the ORMDLs in mammalian cells. These proteins form stable complexes with SPT. In yeast, the homeostatic regulation of SPT relies, at least in part, on phosphorylation of the Orms. However, this does not appear to be the case for the mammalian ORMDLs. Here, we accomplished a cell-free reconstitution of the sphingolipid regulation of the ORMDL-SPT complex to probe the underlying regulatory mechanism. Sphingolipid and ORMDL-dependent regulation of SPT was demonstrated in isolated membranes, essentially free of cytosol. This suggests that this regulation does not require soluble cytosolic proteins or small molecules such as ATP. We found that this system is particularly responsive to the pro-apoptotic sphingolipid ceramide and that this response is strictly stereospecific, indicating that ceramide regulates the ORMDL-SPT complex via a specific binding interaction. Yeast membranes harboring the Orm-SPT system also directly responded to sphingolipid, suggesting that yeast cells have, in addition to Orm phosphorylation, an additional Orm-dependent SPT regulatory mechanism. Our results indicate that ORMDL/Orm-mediated regulation of SPT involves a direct interaction of sphingolipid with the membrane-bound components of the SPT-regulatory apparatus.
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Affiliation(s)
- Deanna L Davis
- From the Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298
| | - Kenneth Gable
- the Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, and
| | - John Suemitsu
- From the Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298
| | - Teresa M Dunn
- the Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, and
| | - Binks W Wattenberg
- From the Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, .,the James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, Kentucky 40202
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Kappel S, Borgström A, Stokłosa P, Dörr K, Peinelt C. Store-operated calcium entry in disease: Beyond STIM/Orai expression levels. Semin Cell Dev Biol 2019; 94:66-73. [PMID: 30630032 DOI: 10.1016/j.semcdb.2019.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/29/2018] [Accepted: 01/05/2019] [Indexed: 12/19/2022]
Abstract
Precise intracellular calcium signaling is crucial to numerous cellular functions. In non-excitable cells, store-operated calcium entry (SOCE) is a key step in the generation of intracellular calcium signals. Tight regulation of SOCE is important, and dysregulation is involved in several pathophysiological cellular malfunctions. The current underlying SOCE, calcium release-activated calcium current (ICRAC), was first discovered almost three decades ago. Since its discovery, the molecular components of ICRAC, Orai1 and stromal interaction molecule 1 (STIM1), have been extensively investigated. Several regulatory mechanisms and proteins contribute to alterations in SOCE and cellular malfunctions in cancer, immune and neurodegenerative diseases, inflammation, and neuronal disorders. This review summarizes these regulatory mechanisms, including glycosylation, pH sensing, and the regulatory proteins golli, α-SNAP, SARAF, ORMDL3, CRACR2A, and TRPM4 channels.
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Affiliation(s)
- Sven Kappel
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Anna Borgström
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Paulina Stokłosa
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | | | - Christine Peinelt
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
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50
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Transmembrane topology of mammalian ORMDL proteins in the endoplasmic reticulum as revealed by the substituted cysteine accessibility method (SCAM™). BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:382-395. [PMID: 30639427 DOI: 10.1016/j.bbapap.2019.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/19/2018] [Accepted: 01/06/2019] [Indexed: 01/05/2023]
Abstract
Sphingolipids are diverse lipids with essential, and occasionally opposing, functions in the cell and therefore tight control over biosynthesis is vital. Mechanisms governing this regulation are not understood. Initial steps in sphingolipid biosynthesis take place on the cytosolic face of the endoplasmic reticulum (ER). Serine palmitoyltransferase (SPT) is an ER-resident enzyme catalyzing the first-committed step in sphingolipid biosynthesis. Not surprisingly, SPT activity is tightly regulated. ORMDLs are ER-resident proteins recently identified as regulators of SPT activity. ORMDL proteins interact directly with SPT but the nature of this interaction is unknown. ORMDL protein sequences contain hydrophobic regions, yet algorithm-based predictions of transmembrane segments are highly ambiguous, making topology of this key regulator unclear. Here we report use of substituted cysteine accessibility to analyze topology of mammalian ORMDLs. We constructed multiple mutant ORMDLs, each containing a single cysteine strategically placed along the protein length. Combined use of selective membrane permeabilization with an impermeant cysteine modification reagent allowed us to assign transmembrane and cytosolic segments of ORMDL. We confirmed that mammalian ORMDL proteins transit the membrane four times, with amino- and carboxy termini facing the cytosol along with a large cytosolic loop. This model will allow us to determine details of the ORMDL-SPT interaction and identify regions acting as the "lipid sensor" to detect changes in cellular sphingolipid levels. We also observe that SPT and ORMDL are substantially resistant to extraction from membranes with non-ionic detergent, indirectly suggesting that both proteins reside in a specialized subdomain of the ER.
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