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Girik V, van Ek L, Dentand Quadri I, Azam M, Cruz Cobo M, Mandavit M, Riezman I, Riezman H, Gavin AC, Nunes-Hasler P. Development of Genetically Encoded Fluorescent KSR1-Based Probes to Track Ceramides during Phagocytosis. Int J Mol Sci 2024; 25:2996. [PMID: 38474242 DOI: 10.3390/ijms25052996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 02/26/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Ceramides regulate phagocytosis; however, their exact function remains poorly understood. Here, we sought (1) to develop genetically encoded fluorescent tools for imaging ceramides, and (2) to use them to examine ceramide dynamics during phagocytosis. Fourteen enhanced green fluorescent protein (EGFP) fusion constructs based on four known ceramide-binding domains were generated and screened. While most constructs localized to the nucleus or cytosol, three based on the CA3 ceramide-binding domain of kinase suppressor of ras 1 (KSR1) localized to the plasma membrane or autolysosomes. C-terminally tagged CA3 with a vector-based (C-KSR) or glycine-serine linker (C-KSR-GS) responded sensitively and similarly to ceramide depletion and accumulation using a panel of ceramide modifying drugs, whereas N-terminally tagged CA3 (N-KSR) responded differently to a subset of treatments. Lipidomic and liposome microarray analysis suggested that, instead, N-KSR may preferentially bind glucosyl-ceramide. Additionally, the three probes showed distinct dynamics during phagocytosis. Despite partial autolysosomal degradation, C-KSR and C-KSR-GS accumulated at the plasma membrane during phagocytosis, whereas N-KSR did not. Moreover, the weak recruitment of C-KSR-GS to the endoplasmic reticulum and phagosomes was enhanced through overexpression of the endoplasmic reticulum proteins stromal interaction molecule 1 (STIM1) and Sec22b, and was more salient in dendritic cells. The data suggest these novel probes can be used to analyze sphingolipid dynamics and function in living cells.
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Affiliation(s)
- Vladimir Girik
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Larissa van Ek
- Department of Cellular Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
- Diabetes Center, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Isabelle Dentand Quadri
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Maral Azam
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - María Cruz Cobo
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Marion Mandavit
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Isabelle Riezman
- Department of Biochemistry, NCCR Chemical Biology, Faculty of Science, University of Geneva, 1211 Geneva, Switzerland
| | - Howard Riezman
- Department of Biochemistry, NCCR Chemical Biology, Faculty of Science, University of Geneva, 1211 Geneva, Switzerland
| | - Anne-Claude Gavin
- Department of Cellular Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
- Diabetes Center, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
- Department of Biochemistry, NCCR Chemical Biology, Faculty of Science, University of Geneva, 1211 Geneva, Switzerland
| | - Paula Nunes-Hasler
- Department of Pathology and Immunology, Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
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Ebstrup ML, Sønder SL, Fogde DL, Heitmann ASB, Dietrich TN, Dias C, Jäättelä M, Maeda K, Nylandsted J. Annexin A7 mediates lysosome repair independently of ESCRT-III. Front Cell Dev Biol 2024; 11:1211498. [PMID: 38348092 PMCID: PMC10860759 DOI: 10.3389/fcell.2023.1211498] [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: 04/24/2023] [Accepted: 12/21/2023] [Indexed: 02/15/2024] Open
Abstract
Lysosomes are crucial organelles essential for various cellular processes, and any damage to them can severely compromise cell viability. This study uncovers a previously unrecognized function of the calcium- and phospholipid-binding protein Annexin A7 in lysosome repair, which operates independently of the Endosomal Sorting Complex Required for Transport (ESCRT) machinery. Our research reveals that Annexin A7 plays a role in repairing damaged lysosomes, different from its role in repairing the plasma membrane, where it facilitates repair through the recruitment of ESCRT-III components. Notably, our findings strongly suggest that Annexin A7, like the ESCRT machinery, is dispensable for membrane contact site formation within the newly discovered phosphoinositide-initiated membrane tethering and lipid transport (PITT) pathway. Instead, we speculate that Annexin A7 is recruited to damaged lysosomes and promotes repair through its membrane curvature and cross-linking capabilities. Our findings provide new insights into the diverse mechanisms underlying lysosomal membrane repair and highlight the multifunctional role of Annexin A7 in membrane repair.
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Affiliation(s)
| | | | | | | | | | - Catarina Dias
- Membrane Integrity, Danish Cancer Institute, Copenhagen, Denmark
| | - Marja Jäättelä
- Cell Death and Metabolism, Danish Cancer Institute, Copenhagen, Denmark
- Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kenji Maeda
- Cell Death and Metabolism, Danish Cancer Institute, Copenhagen, Denmark
| | - Jesper Nylandsted
- Membrane Integrity, Danish Cancer Institute, Copenhagen, Denmark
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
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3
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Diaz-Vegas A, Madsen S, Cooke KC, Carroll L, Khor JXY, Turner N, Lim XY, Astore MA, Morris JC, Don AS, Garfield A, Zarini S, Zemski Berry KA, Ryan AP, Bergman BC, Brozinick JT, James DE, Burchfield JG. Mitochondrial electron transport chain, ceramide, and coenzyme Q are linked in a pathway that drives insulin resistance in skeletal muscle. eLife 2023; 12:RP87340. [PMID: 38149844 PMCID: PMC10752590 DOI: 10.7554/elife.87340] [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] [Indexed: 12/28/2023] Open
Abstract
Insulin resistance (IR) is a complex metabolic disorder that underlies several human diseases, including type 2 diabetes and cardiovascular disease. Despite extensive research, the precise mechanisms underlying IR development remain poorly understood. Previously we showed that deficiency of coenzyme Q (CoQ) is necessary and sufficient for IR in adipocytes and skeletal muscle (Fazakerley et al., 2018). Here, we provide new insights into the mechanistic connections between cellular alterations associated with IR, including increased ceramides, CoQ deficiency, mitochondrial dysfunction, and oxidative stress. We demonstrate that elevated levels of ceramide in the mitochondria of skeletal muscle cells result in CoQ depletion and loss of mitochondrial respiratory chain components, leading to mitochondrial dysfunction and IR. Further, decreasing mitochondrial ceramide levels in vitro and in animal models (mice, C57BL/6J) (under chow and high-fat diet) increased CoQ levels and was protective against IR. CoQ supplementation also rescued ceramide-associated IR. Examination of the mitochondrial proteome from human muscle biopsies revealed a strong correlation between the respirasome system and mitochondrial ceramide as key determinants of insulin sensitivity. Our findings highlight the mitochondrial ceramide-CoQ-respiratory chain nexus as a potential foundation of an IR pathway that may also play a critical role in other conditions associated with ceramide accumulation and mitochondrial dysfunction, such as heart failure, cancer, and aging. These insights may have important clinical implications for the development of novel therapeutic strategies for the treatment of IR and related metabolic disorders.
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Affiliation(s)
- Alexis Diaz-Vegas
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
| | - Søren Madsen
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
| | - Kristen C Cooke
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
| | - Luke Carroll
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
| | - Jasmine XY Khor
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, University of SydneySydneyAustralia
| | - Nigel Turner
- Cellular Bioenergetics Laboratory, Victor Chang Cardiac Research InstituteSydneyAustralia
| | - Xin Y Lim
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, University of SydneySydneyAustralia
| | - Miro A Astore
- Center for Computational Biology and Center for Computational Mathematics, Flatiron InstituteNew YorkUnited States
| | | | - Anthony S Don
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, University of SydneySydneyAustralia
| | - Amanda Garfield
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Simona Zarini
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Karin A Zemski Berry
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Andrew P Ryan
- Lilly Research Laboratories, Division of Eli Lilly and CompanyIndianapolisUnited States
| | - Bryan C Bergman
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Joseph T Brozinick
- Lilly Research Laboratories, Division of Eli Lilly and CompanyIndianapolisUnited States
| | - David E James
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, University of SydneySydneyAustralia
| | - James G Burchfield
- Charles Perkins Centre, School of life and Environmental Sciences, University of SydneySydneyAustralia
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4
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Diaz-Vegas A, Madsen S, Cooke KC, Carroll L, Khor JXY, Turner N, Lim XY, Astore MA, Morris J, Don A, Garfield A, Zarini S, Zemski Berry KA, Ryan A, Bergman BC, Brozinick JT, James DE, Burchfield JG. Mitochondrial electron transport chain, ceramide and Coenzyme Q are linked in a pathway that drives insulin resistance in skeletal muscle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.10.532020. [PMID: 36945619 PMCID: PMC10028964 DOI: 10.1101/2023.03.10.532020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Abstract
Insulin resistance (IR) is a complex metabolic disorder that underlies several human diseases, including type 2 diabetes and cardiovascular disease. Despite extensive research, the precise mechanisms underlying IR development remain poorly understood. Here, we provide new insights into the mechanistic connections between cellular alterations associated with IR, including increased ceramides, deficiency of coenzyme Q (CoQ), mitochondrial dysfunction, and oxidative stress. We demonstrate that elevated levels of ceramide in the mitochondria of skeletal muscle cells results in CoQ depletion and loss of mitochondrial respiratory chain components, leading to mitochondrial dysfunction and IR. Further, decreasing mitochondrial ceramide levels in vitro and in animal models (under chow and high fat diet) increased CoQ levels and was protective against IR. CoQ supplementation also rescued ceramide-associated IR. Examination of the mitochondrial proteome from human muscle biopsies revealed a strong correlation between the respirasome system and mitochondrial ceramide as key determinants of insulin sensitivity. Our findings highlight the mitochondrial Ceramide-CoQ-respiratory chain nexus as a potential foundation of an IR pathway that may also play a critical role in other conditions associated with ceramide accumulation and mitochondrial dysfunction, such as heart failure, cancer, and aging. These insights may have important clinical implications for the development of novel therapeutic strategies for the treatment of IR and related metabolic disorders.
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Affiliation(s)
- Alexis Diaz-Vegas
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Soren Madsen
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Kristen C. Cooke
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Luke Carroll
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Jasmine X. Y. Khor
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, 2050, Australia
| | - Nigel Turner
- Cellular Bioenergetics Laboratory, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Xin Ying Lim
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, 2050, Australia
| | - Miro A. Astore
- Center for Computational Biology and Center for Computational Mathematics, Flatiron Institute, New York, NY 10010, USA
| | - Jonathan Morris
- School of Chemistry, UNSW Sydney, Sydney, 2052, NSW, Australia
| | - Anthony Don
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, 2050, Australia
| | - Amanda Garfield
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Simona Zarini
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Karin A. Zemski Berry
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Andrew Ryan
- Lilly Research Laboratories, Division of Eli Lilly and Company, Indianapolis, IN, USA
| | - Bryan C. Bergman
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Joseph T. Brozinick
- Lilly Research Laboratories, Division of Eli Lilly and Company, Indianapolis, IN, USA
| | - David E. James
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
- Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, 2050, Australia
| | - James G. Burchfield
- Charles Perkins Centre, School of life and Environmental Sciences, University of Sydney, Sydney, Australia
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5
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Zhu H, Chen HJ, Wen HY, Wang ZG, Liu SL. Engineered Lipidic Nanomaterials Inspired by Sphingomyelin Metabolism for Cancer Therapy. Molecules 2023; 28:5366. [PMID: 37513239 PMCID: PMC10383197 DOI: 10.3390/molecules28145366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Sphingomyelin (SM) and its metabolites are crucial regulators of tumor cell growth, differentiation, senescence, and programmed cell death. With the rise in lipid-based nanomaterials, engineered lipidic nanomaterials inspired by SM metabolism, corresponding lipid targeting, and signaling activation have made fascinating advances in cancer therapeutic processes. In this review, we first described the specific pathways of SM metabolism and the roles of their associated bioactive molecules in mediating cell survival or death. We next summarized the advantages and specific applications of SM metabolism-based lipidic nanomaterials in specific cancer therapies. Finally, we discussed the challenges and perspectives of this emerging and promising SM metabolism-based nanomaterials research area.
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Affiliation(s)
- Han Zhu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine, Nankai University, Tianjin 300071, China
| | - Hua-Jie Chen
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Hai-Yan Wen
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Zhi-Gang Wang
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine, Nankai University, Tianjin 300071, China
| | - Shu-Lin Liu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine, Nankai University, Tianjin 300071, China
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
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6
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Raj N, Greune L, Kahms M, Mildner K, Franzkoch R, Psathaki OE, Zobel T, Zeuschner D, Klingauf J, Gerke V. Early Endosomes Act as Local Exocytosis Hubs to Repair Endothelial Membrane Damage. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300244. [PMID: 36938863 PMCID: PMC10161044 DOI: 10.1002/advs.202300244] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/21/2023] [Indexed: 05/06/2023]
Abstract
The plasma membrane of a cell is subject to stresses causing ruptures that must be repaired immediately to preserve membrane integrity and ensure cell survival. Yet, the spatio-temporal membrane dynamics at the wound site and the source of the membrane required for wound repair are poorly understood. Here, it is shown that early endosomes, previously only known to function in the uptake of extracellular material and its endocytic transport, are involved in plasma membrane repair in human endothelial cells. Using live-cell imaging and correlative light and electron microscopy, it is demonstrated that membrane injury triggers a previously unknown exocytosis of early endosomes that is induced by Ca2+ entering through the wound. This exocytosis is restricted to the vicinity of the wound site and mediated by the endosomal soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) VAMP2, which is crucial for efficient membrane repair. Thus, the newly identified Ca2+ -evoked and localized exocytosis of early endosomes supplies the membrane material required for rapid resealing of a damaged plasma membrane, thereby providing the first line of defense against damage in mechanically challenged endothelial cells.
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Affiliation(s)
- Nikita Raj
- Institute of Medical Biochemistry, Centre for Molecular Biology of Inflammation (ZMBE), Cells in Motion Interfaculty Center, University of Münster, 48149, Münster, Germany
| | - Lilo Greune
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, 48149, Münster, Germany
| | - Martin Kahms
- Institute of Medical Physics and Biophysics, University of Münster, 48149, Münster, Germany
| | - Karina Mildner
- Electron Microscopy Facility, Max Planck Institute for Molecular Biomedicine, 48149, Münster, Germany
| | - Rico Franzkoch
- Department of Biology, integrated Bioimaging Facility (iBiOs), Center of Cellular Nanoanalytics (CellNanO), University of Osnabrück, 49076, Osnabrück, Germany
| | - Olympia Ekaterini Psathaki
- Department of Biology, integrated Bioimaging Facility (iBiOs), Center of Cellular Nanoanalytics (CellNanO), University of Osnabrück, 49076, Osnabrück, Germany
| | - Thomas Zobel
- Imaging Network, Cells in Motion Interfaculty Centre, University of Münster, 48149, Münster, Germany
| | - Dagmar Zeuschner
- Electron Microscopy Facility, Max Planck Institute for Molecular Biomedicine, 48149, Münster, Germany
| | - Jürgen Klingauf
- Institute of Medical Physics and Biophysics, University of Münster, 48149, Münster, Germany
| | - Volker Gerke
- Institute of Medical Biochemistry, Centre for Molecular Biology of Inflammation (ZMBE), Cells in Motion Interfaculty Center, University of Münster, 48149, Münster, Germany
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7
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Barisch C, Holthuis JCM, Cosentino K. Membrane damage and repair: a thin line between life and death. Biol Chem 2023; 404:467-490. [PMID: 36810295 DOI: 10.1515/hsz-2022-0321] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 02/03/2023] [Indexed: 02/24/2023]
Abstract
Bilayered membranes separate cells from their surroundings and form boundaries between intracellular organelles and the cytosol. Gated transport of solutes across membranes enables cells to establish vital ion gradients and a sophisticated metabolic network. However, an advanced compartmentalization of biochemical reactions makes cells also particularly vulnerable to membrane damage inflicted by pathogens, chemicals, inflammatory responses or mechanical stress. To avoid potentially lethal consequences of membrane injuries, cells continuously monitor the structural integrity of their membranes and readily activate appropriate pathways to plug, patch, engulf or shed the damaged membrane area. Here, we review recent insights into the cellular mechanisms that underly an effective maintenance of membrane integrity. We discuss how cells respond to membrane lesions caused by bacterial toxins and endogenous pore-forming proteins, with a primary focus on the intimate crosstalk between membrane proteins and lipids during wound formation, detection and elimination. We also discuss how a delicate balance between membrane damage and repair determines cell fate upon bacterial infection or activation of pro-inflammatory cell death pathways.
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Affiliation(s)
- Caroline Barisch
- Molecular Infection Biology Division, Department of Biology and Center of Cellular Nanoanalytics, Osnabrück University, D-49076 Osnabrück, Germany
| | - Joost C M Holthuis
- Molecular Cell Biology Division, Department of Biology and Center of Cellular Nanoanalytics, Osnabrück University, D-49076 Osnabrück, Germany
| | - Katia Cosentino
- Molecular Cell Biophysics Division, Department of Biology and Center of Cellular Nanoanalytics, Osnabrück University, D-49076 Osnabrück, Germany
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8
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Enrich C, Lu A, Tebar F, Rentero C, Grewal T. Ca 2+ and Annexins - Emerging Players for Sensing and Transferring Cholesterol and Phosphoinositides via Membrane Contact Sites. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:393-438. [PMID: 36988890 DOI: 10.1007/978-3-031-21547-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Maintaining lipid composition diversity in membranes from different organelles is critical for numerous cellular processes. However, many lipids are synthesized in the endoplasmic reticulum (ER) and require delivery to other organelles. In this scenario, formation of membrane contact sites (MCS) between neighbouring organelles has emerged as a novel non-vesicular lipid transport mechanism. Dissecting the molecular composition of MCS identified phosphoinositides (PIs), cholesterol, scaffolding/tethering proteins as well as Ca2+ and Ca2+-binding proteins contributing to MCS functioning. Compelling evidence now exists for the shuttling of PIs and cholesterol across MCS, affecting their concentrations in distinct membrane domains and diverse roles in membrane trafficking. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) at the plasma membrane (PM) not only controls endo-/exocytic membrane dynamics but is also critical in autophagy. Cholesterol is highly concentrated at the PM and enriched in recycling endosomes and Golgi membranes. MCS-mediated cholesterol transfer is intensely researched, identifying MCS dysfunction or altered MCS partnerships to correlate with de-regulated cellular cholesterol homeostasis and pathologies. Annexins, a conserved family of Ca2+-dependent phospholipid binding proteins, contribute to tethering and untethering events at MCS. In this chapter, we will discuss how Ca2+ homeostasis and annexins in the endocytic compartment affect the sensing and transfer of cholesterol and PIs across MCS.
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Affiliation(s)
- Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.
| | - Albert Lu
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Thomas Grewal
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
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9
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Suppression of annexin A1 and its receptor reduces herpes simplex virus 1 lethality in mice. PLoS Pathog 2022; 18:e1010692. [PMID: 35939498 PMCID: PMC9359538 DOI: 10.1371/journal.ppat.1010692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/20/2022] [Indexed: 11/27/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1)-induced encephalitis is the most common cause of sporadic, fatal encephalitis in humans. HSV-1 has at least 10 different envelope glycoproteins, which can promote virus infection. The ligands for most of the envelope glycoproteins and the significance of these ligands in virus-induced encephalitis remain elusive. Here, we show that glycoprotein E (gE) binds to the cellular protein, annexin A1 (Anx-A1) to enhance infection. Anx-A1 can be detected on the surface of cells permissive for HSV-1 before infection and on virions. Suppression of Anx-A1 or its receptor, formyl peptide receptor 2 (FPR2), on the cell surface and gE or Anx-A1 on HSV-1 envelopes reduced virus binding to cells. Importantly, Anx-A1 knockout, Anx-A1 knockdown, or treatments with the FPR2 antagonist reduced the mortality and tissue viral loads of infected mice. Our results show that Anx-A1 is a novel enhancing factor of HSV-1 infection. Anx-A1-deficient mice displayed no evident physiology and behavior changes. Hence, targeting Anx-A1 and FPR2 could be a promising prophylaxis or adjuvant therapy to decrease HSV-1 lethality. Herpes simplex virus 1 (HSV-1)-induced encephalitis is the most devastating consequence of HSV-1 infection, even in patients treated with anti-HSV-1 drugs. Moreover, encephalitis induced by drug-resistant HSV-1 has been reported in immunocompromised patients. Identifying the cellular factors in promoting HSV-1 replication, especially those increasing virus attachment and entry, could facilitate the development of alternative or adjuvant therapy. Here, we identified annexin A1 (Anx-A1) and its receptor, formyl peptide receptor 2 (FPR2), facilitating HSV-1 attachment to the cell surface. Suppression of Anx-A1 or blockage of FPR2 impaired HSV-1 attachment to cells, viral yields in cells, and HSV-1 lethality in mice. Moreover, blocking FPR2 decreased the replication of drug-resistant HSV-1 in BABL/c nude mice. Hence, targeting Anx-A1 and FPR2 could be alternative or adjuvant therapy for HSV-1 infection.
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10
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Chen Y, Li G, Bhat OM, Li X, Zhang Y, Li PL. Impairment of Ceramide-Mediated Endothelial Instant Membrane Resealing During Diabetes Mellitus. Front Physiol 2022; 13:910339. [PMID: 35874544 PMCID: PMC9298829 DOI: 10.3389/fphys.2022.910339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/14/2022] [Indexed: 01/01/2023] Open
Abstract
Recent studies have indicated that instant cell membrane resealing (ICMR) controls the activation of NOD-like receptor pyrin domain containing 3 (Nlrp3) inflammasomes in endothelial cells, thereby initiating and promoting vascular inflammation. It remains unknown whether this impaired ICMR occurs under diabetic condition or hyperglycemia contributing to endothelial dysfunction leading to vascular inflammation, a hallmark of diabetic vascular injury. The present study aims to examine whether ICMR occurs during in control and diabetic mice and to explore related molecular mechanisms associated with acid sphingomyelinase (ASM)-mediated ceramide production. Using confocal microscopy, we demonstrated that mouse aortic endothelial cells (MAECs) exposed to high glucose levels exhibited much more retarded ICMR after laser-induced membrane injury, compared to that in control cells. The high glucose-induced impairment of membrane resealing in MAECs was prevented when these cells were pretreated with sphingomyelin or C24-ceramide. Mechanistically, high glucose treatment decreased association of membrane ceramide with annexin A5, an essential element of membrane repair machinery. Consistently, the association of ceramide with annexin A5 was significantly reduced in the coronary arterial endothelium of mice with streptozotocin-induced diabetes mellitus compared to that in non-diabetic control mice. Moreover, a marked reduction of the association of ceramide with annexin A5 was observed in coronary arterial endothelium of ASM knockout mice regardless of their diabetic status. Lastly, high glucose treatment or ASM gene deletion substantially impaired ICMR in coronary arterial endothelium of mice receiving membrane puncturing agents. Collectively, our data suggest that ceramide-mediated ICMR in vascular endothelial cells is impaired during diabetes mellitus due to dissociation of ceramide with annexin A5 and ASM play a critical role in this ICMR.
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Affiliation(s)
- Yang Chen
- School of Chinese Materia Medica, Guangzhou University of Chinese Medicine, Guangzhou, China
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Guangbi Li
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Owais M. Bhat
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Xiang Li
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, United States
| | - Yang Zhang
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, United States
| | - Pin-Lan Li
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
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11
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Ray S, Roth R, Keyel PA. Membrane repair triggered by cholesterol-dependent cytolysins is activated by mixed lineage kinases and MEK. SCIENCE ADVANCES 2022; 8:eabl6367. [PMID: 35294243 PMCID: PMC8926344 DOI: 10.1126/sciadv.abl6367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Repair of plasma membranes damaged by bacterial pore-forming toxins, such as streptolysin O or perfringolysin O, during septic cardiomyopathy or necrotizing soft tissue infections is mediated by several protein families. However, the activation of these proteins downstream of ion influx is poorly understood. Here, we demonstrate that following membrane perforation by bacterial cholesterol-dependent cytolysins, calcium influx activates mixed lineage kinase 3 independently of protein kinase C or ceramide generation. Mixed lineage kinase 3 uncouples mitogen-activated kinase kinase (MEK) and extracellular-regulated kinase (ERK) signaling. MEK signals via an ERK-independent pathway to promote rapid annexin A2 membrane recruitment and enhance microvesicle shedding. This pathway accounted for 70% of all calcium ion-dependent repair responses to streptolysin O and perfringolysin O, but only 50% of repair to intermedilysin. We conclude that mixed lineage kinase signaling via MEK coordinates microvesicle shedding, which is critical for cellular survival against cholesterol-dependent cytolysins.
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Affiliation(s)
- Sucharit Ray
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Robyn Roth
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Peter A. Keyel
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
- Corresponding author.
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12
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Rühl S, Broz P. Regulation of Lytic and Non-Lytic Functions of Gasdermin Pores. J Mol Biol 2021; 434:167246. [PMID: 34537232 DOI: 10.1016/j.jmb.2021.167246] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/03/2021] [Accepted: 09/10/2021] [Indexed: 12/13/2022]
Abstract
Pyroptosis is a necrotic form of cell death that was initially found to be induced upon activation of inflammatory caspases by inflammasome complexes. Mechanistically, pyroptosis induction requires cleavage of the caspase substrate gasdermin D (GSDMD), and the release of the GSDMD N-terminal fragment, which targets the plasma membrane to form large β-barrel pores. GSDMD shares this pore-forming ability with other gasdermin family members, which induce pyroptosis during infection or upon treatment with chemotherapy drugs. While induction of cell death has been assumed to be the main function of the gasdermin pores, increasing evidence suggests that these pores have non-lytic functions, such as in releasing cytokines or alarmins and in regulating intracellular signaling via ionic fluxes. Here we discuss how gasdermin pore formation is regulated to induce membrane permeabilization or lysis, how gasdermin pores achieve specificity for cargo-release and how cells repair gasdermin-induced damage to the plasma membrane.
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Affiliation(s)
- Sebastian Rühl
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Petr Broz
- Department of Biochemistry, University of Lausanne, 1066 Epalinges, Switzerland.
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13
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Krones D, Rühling M, Becker KA, Kunz TC, Sehl C, Paprotka K, Gulbins E, Fraunholz M. Staphylococcus aureus α-Toxin Induces Acid Sphingomyelinase Release From a Human Endothelial Cell Line. Front Microbiol 2021; 12:694489. [PMID: 34394034 PMCID: PMC8358437 DOI: 10.3389/fmicb.2021.694489] [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: 04/13/2021] [Accepted: 07/05/2021] [Indexed: 11/14/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is well known to express a plethora of toxins of which the pore-forming hemolysin A (α-toxin) is the best-studied cytolysin. Pore-forming toxins (PFT) permeabilize host membranes during infection thereby causing concentration-dependent effects in host cell membranes ranging from disordered ion fluxes to cytolysis. Host cells possess defense mechanisms against PFT attack, resulting in endocytosis of the breached membrane area and delivery of repair vesicles to the insulted plasma membrane as well as a concurrent release of membrane repair enzymes. Since PFTs from several pathogens have been shown to recruit membrane repair components, we here investigated whether staphylococcal α-toxin is able to induce these mechanisms in endothelial cells. We show that S. aureus α-toxin induced increase in cytosolic Ca2+ in endothelial cells, which was accompanied by p38 MAPK phosphorylation. Toxin challenge led to increased endocytosis of an extracellular fluid phase marker as well as increased externalization of LAMP1-positive membranes suggesting that peripheral lysosomes are recruited to the insulted plasma membrane. We further observed that thereby the lysosomal protein acid sphingomyelinase (ASM) was released into the cell culture medium. Thus, our results show that staphylococcal α-toxin triggers mechanisms in endothelial cells, which have been implicated in membrane repair after damage of other cell types by different toxins.
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Affiliation(s)
- David Krones
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Marcel Rühling
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Katrin Anne Becker
- Institute of Molecular Biology, University of Duisburg-Essen, University Hospital, Essen, Germany
| | - Tobias C Kunz
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Carolin Sehl
- Institute of Molecular Biology, University of Duisburg-Essen, University Hospital, Essen, Germany
| | - Kerstin Paprotka
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Erich Gulbins
- Institute of Molecular Biology, University of Duisburg-Essen, University Hospital, Essen, Germany.,Department of Surgery, College of Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Martin Fraunholz
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
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14
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Xiang H, Jin S, Tan F, Xu Y, Lu Y, Wu T. Physiological functions and therapeutic applications of neutral sphingomyelinase and acid sphingomyelinase. Biomed Pharmacother 2021; 139:111610. [PMID: 33957567 DOI: 10.1016/j.biopha.2021.111610] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/05/2021] [Accepted: 04/12/2021] [Indexed: 11/15/2022] Open
Abstract
Sphingomyelin (SM) can be converted into ceramide (Cer) by neutral sphingomyelinase (NSM) and acid sphingomyelinase (ASM). Cer is a second messenger of lipids and can regulate cell growth and apoptosis. Increasing evidence shows that NSM and ASM play key roles in many processes, such as apoptosis, immune function and inflammation. Therefore, NSM and ASM have broad prospects in clinical treatments, especially in cancer, cardiovascular diseases (such as atherosclerosis), nervous system diseases (such as Alzheimer's disease), respiratory diseases (such as chronic obstructive pulmonary disease) and the phenotype of dwarfisms in adolescents, playing a complex regulatory role. This review focuses on the physiological functions of NSM and ASM and summarizes their roles in certain diseases and their potential applications in therapy.
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Affiliation(s)
- Hongjiao Xiang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Shengjie Jin
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Fenglang Tan
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yifan Xu
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yifei Lu
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Tao Wu
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
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15
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Fisher-Wellman KH, Hagen JT, Neufer PD, Kassai M, Cabot MC. On the nature of ceramide-mitochondria interactions - Dissection using comprehensive mitochondrial phenotyping. Cell Signal 2020; 78:109838. [PMID: 33212155 DOI: 10.1016/j.cellsig.2020.109838] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 02/06/2023]
Abstract
Sphingolipids are a unique class of lipids owing to their non-glycerol-containing backbone, ceramide, that is constructed from a long-chain aliphatic amino alcohol, sphinganine, to which a fatty acid is attached via an amide bond. Ceramide plays a star role in the initiation of apoptosis by virtue of its interactions with mitochondria, a control point for a downstream array of signaling cascades culminating in apoptosis. Many pathways converge on mitochondria to elicit mitochondrial outer membrane permeabilization (MOMP), a step that corrupts bioenergetic service. Although much is known regarding ceramides interaction with mitochondria and the ensuing cell signal transduction cascades, how ceramide impacts the elements of mitochondrial bioenergetic function is poorly understood. The objective of this review is to introduce the reader to sphingolipid metabolism, present a snapshot of mitochondrial respiration, elaborate on ceramides convergence on mitochondria and the upstream players that collaborate to elicit MOMP, and introduce a mitochondrial phenotyping platform that can be of utility in dissecting the fine-points of ceramide impact on cellular bioenergetics.
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Affiliation(s)
- Kelsey H Fisher-Wellman
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States of America; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States of America.
| | - James T Hagen
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, United States of America; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States of America
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States of America
| | - Miki Kassai
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC, United States of America; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States of America
| | - Myles C Cabot
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC, United States of America; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States of America.
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16
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Interaction of Macrophages and Cholesterol-Dependent Cytolysins: The Impact on Immune Response and Cellular Survival. Toxins (Basel) 2020; 12:toxins12090531. [PMID: 32825096 PMCID: PMC7551085 DOI: 10.3390/toxins12090531] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/13/2020] [Accepted: 08/15/2020] [Indexed: 02/07/2023] Open
Abstract
Cholesterol-dependent cytolysins (CDCs) are key virulence factors involved in many lethal bacterial infections, including pneumonia, necrotizing soft tissue infections, bacterial meningitis, and miscarriage. Host responses to these diseases involve myeloid cells, especially macrophages. Macrophages use several systems to detect and respond to cholesterol-dependent cytolysins, including membrane repair, mitogen-activated protein (MAP) kinase signaling, phagocytosis, cytokine production, and activation of the adaptive immune system. However, CDCs also promote immune evasion by silencing and/or destroying myeloid cells. While there are many common themes between the various CDCs, each CDC also possesses specific features to optimally benefit the pathogen producing it. This review highlights host responses to CDC pathogenesis with a focus on macrophages. Due to their robust plasticity, macrophages play key roles in the outcome of bacterial infections. Understanding the unique features and differences within the common theme of CDCs bolsters new tools for research and therapy.
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17
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Moeng S, Son SW, Lee JS, Lee HY, Kim TH, Choi SY, Kuh HJ, Park JK. Extracellular Vesicles (EVs) and Pancreatic Cancer: From the Role of EVs to the Interference with EV-Mediated Reciprocal Communication. Biomedicines 2020; 8:biomedicines8080267. [PMID: 32756339 PMCID: PMC7459718 DOI: 10.3390/biomedicines8080267] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/25/2020] [Accepted: 08/01/2020] [Indexed: 02/06/2023] Open
Abstract
Pancreatic cancer is malignant and the seventh leading cause of cancer-related deaths worldwide. However, chemotherapy and radiotherapy are—at most—moderately effective, indicating the need for new and different kinds of therapies to manage this disease. It has been proposed that the biologic properties of pancreatic cancer cells are finely tuned by the dynamic microenvironment, which includes extracellular matrix, cancer-associated cells, and diverse immune cells. Accumulating evidence has demonstrated that extracellular vesicles (EVs) play an essential role in communication between heterogeneous subpopulations of cells by transmitting multiplex biomolecules. EV-mediated cell–cell communication ultimately contributes to several aspects of pancreatic cancer, such as growth, angiogenesis, metastasis and therapeutic resistance. In this review, we discuss the role of extracellular vesicles and their cargo molecules in pancreatic cancer. We also present the feasibility of the inhibition of extracellular biosynthesis and their itinerary (release and uptake) for a new attractive therapeutic strategy against pancreatic cancer.
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Affiliation(s)
- Sokviseth Moeng
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Seung Wan Son
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Jong Sun Lee
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Han Yeoung Lee
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Tae Hee Kim
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Soo Young Choi
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
| | - Hyo Jeong Kuh
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea;
| | - Jong Kook Park
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, Chunchon 24252, Korea; (S.M.); (S.W.S.); (J.S.L.); (H.Y.L.); (T.H.K.); (S.Y.C.)
- Correspondence: ; Tel.: +82-33-248-2114
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18
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Walls SM, Cammarato A, Chatfield DA, Ocorr K, Harris GL, Bodmer R. Ceramide-Protein Interactions Modulate Ceramide-Associated Lipotoxic Cardiomyopathy. Cell Rep 2019. [PMID: 29514098 DOI: 10.1016/j.celrep.2018.02.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lipotoxic cardiomyopathy (LCM) is characterized by abnormal myocardial accumulation of lipids, including ceramide; however, the contribution of ceramide to the etiology of LCM is unclear. Here, we investigated the association of ceramide metabolism and ceramide-interacting proteins (CIPs) in LCM in the Drosophila heart model. We find that ceramide feeding or ceramide-elevating genetic manipulations are strongly associated with cardiac dilation and defects in contractility. High ceramide-associated LCM is prevented by inhibiting ceramide synthesis, establishing a robust model of direct ceramide-associated LCM, corroborating previous indirect evidence in mammals. We identified several CIPs from mouse heart and Drosophila extracts, including caspase activator Annexin-X, myosin chaperone Unc-45, and lipogenic enzyme FASN1, and remarkably, their cardiac-specific manipulation can prevent LCM. Collectively, these data suggest that high ceramide-associated lipotoxicity is mediated, in part, through altering caspase activation, sarcomeric maintenance, and lipogenesis, thus providing evidence for conserved mechanisms in LCM pathogenesis in mammals.
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Affiliation(s)
- Stanley M Walls
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA; Department of Cellular and Molecular Biology, San Diego State University, San Diego, CA, USA
| | - Anthony Cammarato
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Dale A Chatfield
- Department of Cellular and Molecular Biology, San Diego State University, San Diego, CA, USA
| | - Karen Ocorr
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Greg L Harris
- Department of Cellular and Molecular Biology, San Diego State University, San Diego, CA, USA.
| | - Rolf Bodmer
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA.
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19
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Brito C, Cabanes D, Sarmento Mesquita F, Sousa S. Mechanisms protecting host cells against bacterial pore-forming toxins. Cell Mol Life Sci 2019; 76:1319-1339. [PMID: 30591958 PMCID: PMC6420883 DOI: 10.1007/s00018-018-2992-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 12/19/2022]
Abstract
Pore-forming toxins (PFTs) are key virulence determinants produced and secreted by a variety of human bacterial pathogens. They disrupt the plasma membrane (PM) by generating stable protein pores, which allow uncontrolled exchanges between the extracellular and intracellular milieus, dramatically disturbing cellular homeostasis. In recent years, many advances were made regarding the characterization of conserved repair mechanisms that allow eukaryotic cells to recover from mechanical disruption of the PM membrane. However, the specificities of the cell recovery pathways that protect host cells against PFT-induced damage remain remarkably elusive. During bacterial infections, the coordinated action of such cell recovery processes defines the outcome of infected cells and is, thus, critical for our understanding of bacterial pathogenesis. Here, we review the cellular pathways reported to be involved in the response to bacterial PFTs and discuss their impact in single-cell recovery and infection.
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Affiliation(s)
- Cláudia Brito
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Didier Cabanes
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
| | - Francisco Sarmento Mesquita
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
- Global Health Institute, School of Life Science, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Sandra Sousa
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
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20
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Ray S, Thapa R, Keyel PA. Multiple Parameters Beyond Lipid Binding Affinity Drive Cytotoxicity of Cholesterol-Dependent Cytolysins. Toxins (Basel) 2018; 11:toxins11010001. [PMID: 30577571 PMCID: PMC6356533 DOI: 10.3390/toxins11010001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/14/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023] Open
Abstract
The largest superfamily of bacterial virulence factors is pore-forming toxins (PFTs). PFTs are secreted by both pathogenic and non-pathogenic bacteria. PFTs sometimes kill or induce pro-pathogen signaling in mammalian cells, all primarily through plasma membrane perforation, though the parameters that determine these outcomes are unclear. Membrane binding, calcium influx, pore size, and membrane repair are factors that influence PFT cytotoxicity. To test the contribution of membrane binding to cytotoxicity and repair, we compared the closely related, similarly-sized PFTs Perfringolysin O (PFO) from Clostridium perfringens and Streptolysin O (SLO) from Streptococcus pyogenes. Cell death kinetics for PFO and SLO were different because PFO increased in cytotoxicity over time. We introduced known L3 loop mutations that swap binding affinity between toxins and measured hemolytic activity, nucleated cell death kinetics and membrane repair using viability assays, and live cell imaging. Altered hemolytic activity was directly proportional to toxin binding affinity. In contrast, L3 loop alterations reduced nucleated cell death, and they had limited effects on cytotoxicity kinetics and membrane repair. This suggests other toxin structural features, like oligomerization, drives these parameters. Overall, these findings suggest that repair mechanisms and toxin oligomerization add constraints beyond membrane binding on toxin evolution and activity against nucleated cells.
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Affiliation(s)
- Sucharit Ray
- Department of Biological Sciences, College of Arts and Sciences, Texas Tech University, Box 43131, Lubbock, TX 79409, USA.
| | - Roshan Thapa
- Department of Biological Sciences, College of Arts and Sciences, Texas Tech University, Box 43131, Lubbock, TX 79409, USA.
| | - Peter A Keyel
- Department of Biological Sciences, College of Arts and Sciences, Texas Tech University, Box 43131, Lubbock, TX 79409, USA.
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21
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Visualizing bioactive ceramides. Chem Phys Lipids 2018; 216:142-151. [PMID: 30266560 DOI: 10.1016/j.chemphyslip.2018.09.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 11/23/2022]
Abstract
In the last 30 years, ceramides have been found to mediate a myriad of biological processes. Ceramides have been recognized as bioactive molecules and their metabolizing enzymes are attractive targets in cancer therapy and other diseases. The molecular mechanism of action of cellular ceramides are still not fully established, with insights into roles through modification of lipid rafts, creation of ceramide platforms, ceramide channels, or through regulation of direct protein effectors such as protein phosphatases and kinases. Recently, the 'Many Ceramides' hypothesis focuses on distinct pools of subcellular ceramides and ceramide species as potential defined bioactive entities. Traditional methods that measure changes in ceramide levels in the whole cell, such as mass spectrometry, fluorescent ceramide analogues, and ceramide antibodies, fail to differentiate specific bioactive species at the subcellular level. However, a few ceramide binding proteins have been reported, and a smaller subgroup within these, have been shown to translocate to ceramide-enriched membranes, revealing these localized pools of bioactive ceramides. In this review we want to discuss and consolidate these works and explore the possibility of defining these binding proteins as new tools are emerging to visualize bioactive ceramides in cells. Our goal is to encourage the scientific community to explore these ceramide partners, to improve techniques to refine the list of these binding partners, making possible the identification of specific domains that recognize and bind ceramides to be used to visualize the 'Many Ceramides' in the cell.
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22
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Schoenauer R, Larpin Y, Babiychuk EB, Drücker P, Babiychuk VS, Avota E, Schneider-Schaulies S, Schumacher F, Kleuser B, Köffel R, Draeger A. Down‐regulation of acid sphingomyelinase and neutral sphingomyelinase‐2 inversely determines the cellular resistance to plasmalemmal injury by pore‐forming toxins. FASEB J 2018; 33:275-285. [DOI: 10.1096/fj.201800033r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Roman Schoenauer
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
| | - Yu Larpin
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
| | - Eduard B. Babiychuk
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
| | - Patrick Drücker
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
| | | | - Elita Avota
- Institute of Virology and ImmunobiologyUniversity of Würzburg Würzburg Germany
| | | | - Fabian Schumacher
- Institute of Nutritional ScienceUniversity of Potsdam Potsdam Germany
| | - Burkhard Kleuser
- Institute of Nutritional ScienceUniversity of Potsdam Potsdam Germany
| | - René Köffel
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
| | - Annette Draeger
- Department of Cell BiologyInstitute of AnatomyUniversity of Bern Bern Switzerland
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D'Angelo G, Moorthi S, Luberto C. Role and Function of Sphingomyelin Biosynthesis in the Development of Cancer. Adv Cancer Res 2018; 140:61-96. [PMID: 30060817 DOI: 10.1016/bs.acr.2018.04.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Sphingomyelin (SM) biosynthesis represents a complex, finely regulated process, mostly occurring in vertebrates. It is intimately linked to lipid transport and it is ultimately carried out by two enzymes, SM synthase 1 and 2, selectively localized in the Golgi and plasma membrane. In the course of the SM biosynthetic reaction, various lipids are metabolized. Because these lipids have both structural and signaling functions, the SM biosynthetic process has the potential to affect diverse important cellular processes (such as cell proliferation, cell survival, and migration). Thus defects in SM biosynthesis might directly or indirectly impact the normal physiology of the cell and eventually of the organism. In this chapter, we will focus on evidence supporting a role for SM biosynthesis in specific cellular functions and how its dysregulation can affect neoplastic transformation.
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Affiliation(s)
- Giovanni D'Angelo
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Sitapriya Moorthi
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, United States
| | - Chiara Luberto
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, United States
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24
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Functional Association between Regulatory RNAs and the Annexins. Int J Mol Sci 2018; 19:ijms19020591. [PMID: 29462943 PMCID: PMC5855813 DOI: 10.3390/ijms19020591] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 12/17/2022] Open
Abstract
Cells respond to pathophysiological states by activation of stress-induced signalling. Regulatory non-coding microRNAs (miRNAs) often form stable feed-forward loops which ensure prolongation of the signal, contributing to sustained activation. Members of the annexin protein family act as sensors for Ca2+, pH, and lipid second messengers, and regulate various signalling pathways. Recently, annexins were reported to participate in feedback loops, suppressing miRNA synthesis and attenuating stress-induced dysregulation of gene expression. They can directly or indirectly associate with RNAs, and are transferred between the cells in exosomes and shed microvesicles. The ability of annexins to recruit other proteins and miRNAs into exosomes implicates them in control of cell–cell interactions, affecting the adaptive responses and remodelling processes during disease. The studies summarized in this Review point to an emerging role of annexins in influencing the synthesis, localisation, and transfer of regulatory RNAs.
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Molino S, Tate E, McKillop WM, Medin JA. Sphingolipid pathway enzymes modulate cell fate and immune responses. Immunotherapy 2017; 9:1185-1198. [DOI: 10.2217/imt-2017-0089] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Sphingolipids (SLs) are a class of essential, bioactive lipids. The SL family includes over 4000 distinct molecules, characterized by their sphingoid base (long-chain aliphatic amine) backbone. SLs are key components of cell membranes, yet their roles go well beyond structure. SLs are involved in many cellular processes including cell differentiation, apoptosis, growth arrest and senescence. As cancer cells routinely display increased growth properties and escape from cell death, it has been suggested that enzymes involved in SL synthesis or catabolism may be altered in cancer cells. In this review, we discuss the role of SL pathway enzymes in cancer, and in acquired resistance to therapy. The use of inhibitors and gene silencing approaches targeting these SL pathways is also explored. Finally, we elaborate on the role of SL pathway enzymes in the tumor microenvironment and their effect on immune cell function.
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Affiliation(s)
- S Molino
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - E Tate
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - WM McKillop
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - JA Medin
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
- Department of Medical Biophysics & the Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Department of Medical Biophysics, University Health Network, Toronto, Ontario, Canada
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Stauffer BB, Cui G, Cottrill KA, Infield DT, McCarty NA. Bacterial Sphingomyelinase is a State-Dependent Inhibitor of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR). Sci Rep 2017; 7:2931. [PMID: 28592822 PMCID: PMC5462758 DOI: 10.1038/s41598-017-03103-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 04/24/2017] [Indexed: 02/07/2023] Open
Abstract
Sphingomyelinase C (SMase) inhibits CFTR chloride channel activity in multiple cell systems, an effect that could exacerbate disease in CF and COPD patients. The mechanism by which sphingomyelin catalysis inhibits CFTR is not known but evidence suggests that it occurs independently of CFTR's regulatory "R" domain. In this study we utilized the Xenopus oocyte expression system to shed light on how CFTR channel activity is reduced by SMase. We found that the pathway leading to inhibition is not membrane delimited and that inhibited CFTR channels remain at the cell membrane, indicative of a novel silencing mechanism. Consistent with an effect on CFTR gating behavior, we found that altering gating kinetics influenced the sensitivity to inhibition by SMase. Specifically, increasing channel activity by introducing the mutation K1250A or pretreating with the CFTR potentiator VX-770 (Ivacaftor) imparted resistance to inhibition. In primary bronchial epithelial cells, we found that basolateral, but not apical, application of SMase leads to a redistribution of sphingomyelin and a reduction in forskolin- and VX-770-stimulated currents. Taken together, these data suggest that SMase inhibits CFTR channel function by locking channels into a closed state and that endogenous CFTR in HBEs is affected by SMase activity.
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Affiliation(s)
- B B Stauffer
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
- Molecular and Systems Pharmacology program, Emory University, 201 Dowman Drive, Atlanta, GA, 20322, USA
| | - G Cui
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
| | - K A Cottrill
- Molecular and Systems Pharmacology program, Emory University, 201 Dowman Drive, Atlanta, GA, 20322, USA
| | - D T Infield
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
| | - N A McCarty
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA.
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Burgert A, Schlegel J, Bécam J, Doose S, Bieberich E, Schubert-Unkmeir A, Sauer M. Characterization of Plasma Membrane Ceramides by Super-Resolution Microscopy. Angew Chem Int Ed Engl 2017; 56:6131-6135. [PMID: 28379629 DOI: 10.1002/anie.201700570] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Indexed: 01/04/2023]
Abstract
The sphingolipid ceramide regulates cellular processes such as differentiation, proliferation, growth arrest, and apoptosis. Ceramide-rich membrane areas promote structural changes within the plasma membrane that segregate membrane receptors and affect membrane curvature and vesicle formation, fusion, and trafficking. Ceramides were labeled by immunocytochemistry to visualize their distribution on the plasma membrane of different cells with virtually molecular resolution by direct stochastic optical reconstruction microscopy (dSTORM). Super-resolution images show that independent of labeling conditions and cell type 50-60 % of all membrane ceramides are located in ceramide-rich platforms (CRPs) with a size of about 75 nm that are composed of at least about 20 ceramides. Treatment of cells with Bacillus cereus sphingomyelinase (bSMase) increases the overall ceramide concentration in the plasma membrane, the quantity of CRPs, and their size. Simultaneously, the ceramide concentration in CRPs increases approximately twofold.
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Affiliation(s)
- Anne Burgert
- Department of Biotechnology and Biophysics, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Jan Schlegel
- Department of Biotechnology and Biophysics, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Jérôme Bécam
- Institute of Hygiene and Microbiology, Julius Maximilian University Würzburg, 97080, Würzburg, Germany
| | - Sören Doose
- Department of Biotechnology and Biophysics, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | | | - Markus Sauer
- Department of Biotechnology and Biophysics, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
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Burgert A, Schlegel J, Bécam J, Doose S, Bieberich E, Schubert‐Unkmeir A, Sauer M. Characterization of Plasma Membrane Ceramides by Super‐Resolution Microscopy. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700570] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Anne Burgert
- Department of Biotechnology and Biophysics Julius Maximilian University Würzburg Am Hubland 97074 Würzburg Germany
| | - Jan Schlegel
- Department of Biotechnology and Biophysics Julius Maximilian University Würzburg Am Hubland 97074 Würzburg Germany
| | - Jérôme Bécam
- Institute of Hygiene and Microbiology Julius Maximilian University Würzburg 97080 Würzburg Germany
| | - Sören Doose
- Department of Biotechnology and Biophysics Julius Maximilian University Würzburg Am Hubland 97074 Würzburg Germany
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine Medical College of Georgia Augusta University Augusta GA 30912 USA
| | | | - Markus Sauer
- Department of Biotechnology and Biophysics Julius Maximilian University Würzburg Am Hubland 97074 Würzburg Germany
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29
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Enrich C, Rentero C, Grewal T. Annexin A6 in the liver: From the endocytic compartment to cellular physiology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:933-946. [PMID: 27984093 DOI: 10.1016/j.bbamcr.2016.10.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 12/15/2022]
Abstract
Annexin A6 (AnxA6) belongs to the conserved annexin family - a group of Ca2+-dependent membrane binding proteins. AnxA6 is the largest of all annexins and highly expressed in smooth muscle, hepatocytes, endothelial cells and cardiomyocytes. Upon activation, AnxA6 binds to negatively charged phospholipids in a wide range of intracellular localizations, in particular the plasma membrane, late endosomes/pre-lysosomes, but also synaptic vesicles and sarcolemma. In these cellular sites, AnxA6 is believed to contribute to the organization of membrane microdomains, such as cholesterol-rich lipid rafts and confer multiple regulatory functions, ranging from vesicle fusion, endocytosis and exocytosis to programmed cell death and muscle contraction. Growing evidence supports that Ca2+ and Ca2+-binding proteins control endocytosis and autophagy. Their regulatory role seems to operate at the level of the signalling pathways that initiate autophagy or at later stages, when autophagosomes fuse with endolysosomal compartments. The convergence of the autophagic and endocytic vesicles to lysosomes shares several features that depend on Ca2+ originating from lysosomes/late endosomes and seems to depend on proteins that are subsequently activated by this cation. However, the involvement of Ca2+ and its effector proteins in these autophagic and endocytic stages still remains poorly understood. Although AnxA6 makes up almost 0.25% of total protein in the liver, little is known about its function in hepatocytes. Within the endocytic route, we identified AnxA6 in endosomes and autophagosomes of hepatocytes. Hence, AnxA6 and possibly other annexins might represent new Ca2+ effectors that regulate converging steps of autophagy and endocytic trafficking in hepatocytes. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cellular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain.
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cellular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Thomas Grewal
- Faculty of Pharmacy A15, University of Sydney, Sydney, NSW 2006, Australia
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30
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The role of neutrophils in inflammation resolution. Semin Immunol 2016; 28:137-45. [DOI: 10.1016/j.smim.2016.03.007] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/11/2016] [Accepted: 03/15/2016] [Indexed: 01/29/2023]
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31
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Inhibition of ceramide de novo synthesis by myriocin produces the double effect of reducing pathological inflammation and exerting antifungal activity against A. fumigatus airways infection. Biochim Biophys Acta Gen Subj 2016; 1860:1089-97. [PMID: 26922830 DOI: 10.1016/j.bbagen.2016.02.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 02/02/2016] [Accepted: 02/22/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND Fungal infections develop in pulmonary chronic inflammatory diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD) and Cystic Fibrosis (CF). The available antifungal drugs may fail to eradicate fungal pathogens, that can invade the lungs and vessels and spread by systemic circulation taking advantage of defective lung immunity. An increased rate of sphingolipid de novo synthesis, leading to ceramide accumulation, was demonstrated in CF and COPD inflamed lungs. The inhibitor of sphingolipid synthesis myriocin reduces inflammation and ameliorates the response against bacterial airway infection in CF mice. Myriocin also inhibits sphingolipid synthesis in fungi and exerts a powerful fungistatic effect. METHODS We treated Aspergillus fumigatus infected airway epithelial cells with myriocin and we administered myriocin-loaded nanocarriers to A. fumigatus infected mice lung. RESULTS We demonstrate here that de novo synthesized ceramide mediates the inflammatory response induced by A. fumigatus infection in airway epithelia. CF epithelial cells are chronically inflamed and defective in killing internalized conidia. Myriocin treatment reduced ceramide increase and inflammatory mediator release whereas it upregulated HO1 and NOD2, allowing the recovery of a functional killing of conidia in these cells. Myriocin-loaded nanocarriers, intratracheally administered to mice, significantly reduced both the inflammatory response induced by A. fumigatus pulmonary challenge and fungal lung invasion. CONCLUSIONS We conclude that inhibition of sphingolipid synthesis can be envisaged as a dual anti-inflammatory and anti-fungal therapy in patients suffering from chronic lung inflammation with compromised immunity. GENERAL SIGNIFICANCE Myriocin represents a powerful agent for inflammatory diseases and fungal infection.
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32
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Eich C, Manzo C, de Keijzer S, Bakker GJ, Reinieren-Beeren I, García-Parajo MF, Cambi A. Changes in membrane sphingolipid composition modulate dynamics and adhesion of integrin nanoclusters. Sci Rep 2016; 6:20693. [PMID: 26869100 PMCID: PMC4751618 DOI: 10.1038/srep20693] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/11/2016] [Indexed: 12/14/2022] Open
Abstract
Sphingolipids are essential constituents of the plasma membrane (PM) and play an important role in signal transduction by modulating clustering and dynamics of membrane receptors. Changes in lipid composition are therefore likely to influence receptor organisation and function, but how this precisely occurs is difficult to address given the intricacy of the PM lipid-network. Here, we combined biochemical assays and single molecule dynamic approaches to demonstrate that the local lipid environment regulates adhesion of integrin receptors by impacting on their lateral mobility. Induction of sphingomyelinase (SMase) activity reduced sphingomyelin (SM) levels by conversion to ceramide (Cer), resulting in impaired integrin adhesion and reduced integrin mobility. Dual-colour imaging of cortical actin in combination with single molecule tracking of integrins showed that this reduced mobility results from increased coupling to the actin cytoskeleton brought about by Cer formation. As such, our data emphasizes a critical role for the PM local lipid composition in regulating the lateral mobility of integrins and their ability to dynamically increase receptor density for efficient ligand binding in the process of cell adhesion.
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Affiliation(s)
- Christina Eich
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Postbox 9101, 6500 HB Nijmegen, The Netherlands
| | - Carlo Manzo
- ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain
| | - Sandra de Keijzer
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Postbox 9101, 6500 HB Nijmegen, The Netherlands
| | - Gert-Jan Bakker
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Postbox 9101, 6500 HB Nijmegen, The Netherlands
| | - Inge Reinieren-Beeren
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Postbox 9101, 6500 HB Nijmegen, The Netherlands
| | - Maria F García-Parajo
- ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.,ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
| | - Alessandra Cambi
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Postbox 9101, 6500 HB Nijmegen, The Netherlands
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Chen Y, Yuan M, Xia M, Wang L, Zhang Y, Li PL. Instant membrane resealing in nlrp3 inflammmasome activation of endothelial cells. Front Biosci (Landmark Ed) 2016; 21:635-50. [PMID: 26709796 DOI: 10.2741/4411] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The present study explored the molecular mechanisms by which instant cell membrane resealing (CMR) controls the activation of NOD-like receptor pyrin domain containing 3 (Nlrp3) inflammasomes. Using wavelength-switching fluorescent microscopy with PI and fura-2 as indicators, we monitored instant CMR simultaneously with (Ca(2+))i in mouse microvascular endothelial cell (MVECs). LCWE or saponin wad found to produce membrane injury, which was resealed in a Ca(2+)-dependent manner, but abolished by FasL, a membrane raft (MR) clustering stimulator. Even in the presence of Ca(2+), FasL prolonged the CMR time as shown by an earlier onset of PI influx (48±12 sec vs. 17±3 min. of control). These effects of FasL were substantially blocked by an MR disruptor, methyl-beta-cyclodextrin (MCD). The failure of CMR upon FasL activated Nlrp3 inflammasomes, which was blocked by MCD, a membrane resealing compound, VA64 or siRNA of an MR-facilitating enzyme, acid sphingomyelinase. This inflammasome activation was due to increased lysosomal permeability and cathepsin B release. It is concluded that an MR-associated CMR protects ECs from Nlrp3 inflammasome activation induced by membrane injury.
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Affiliation(s)
- Yang Chen
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, 1220 East Broad Street, Richmond, VA 23298, 2Department of Pharmacological & Pharmaceutical Sciences College of Pharmacy, University of Houston, 3605 Cullen B
| | | | | | - Lei Wang
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University
| | - Yang Zhang
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204
| | - Pin-Lan Li
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, 1220 East Broad Street, Richmond, VA 23298, 2Department of Pharmacological & Pharmaceutical Sciences College of Pharmacy, University of Houston, 3605 Cullen B,
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Babiychuk EB, Draeger A. Defying death: Cellular survival strategies following plasmalemmal injury by bacterial toxins. Semin Cell Dev Biol 2015; 45:39-47. [PMID: 26481974 DOI: 10.1016/j.semcdb.2015.10.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/12/2015] [Indexed: 10/22/2022]
Abstract
The perforation of the plasmalemma by pore-forming toxins causes an influx of Ca(2+) and an efflux of cytoplasmic constituents. In order to ensure survival, the cell needs to identify, plug and remove lesions from its membrane. Quarantined by membrane folds and isolated by membrane fusion, the pores are removed from the plasmalemma and expelled into the extracellular space. Outward vesiculation and microparticle shedding seem to be the strategies of choice to eliminate toxin-perforated membrane regions from the plasmalemma of host cells. Depending on the cell type and the nature of injury, the membrane lesion can also be taken up by endocytosis and degraded internally. Host cells make excellent use of an initial, moderate rise in intracellular [Ca(2+)], which triggers containment of the toxin-inflicted damage and resealing of the damaged plasmalemma. Additional Ca(2+)-dependent defensive cellular actions range from the release of effector molecules in order to warn neighbouring cells, to the activation of caspases for the initiation of apoptosis in order to eliminate heavily damaged, dysregulated cells. Injury to the plasmalemma by bacterial toxins can be prevented by the early sequestration of bacterial toxins. Artificial liposomes can act as a decoy system preferentially binding and neutralizing bacterial toxins.
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35
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Andrews NW, Corrotte M, Castro-Gomes T. Above the fray: Surface remodeling by secreted lysosomal enzymes leads to endocytosis-mediated plasma membrane repair. Semin Cell Dev Biol 2015; 45:10-7. [PMID: 26433178 DOI: 10.1016/j.semcdb.2015.09.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 09/28/2015] [Indexed: 11/16/2022]
Abstract
The study of plasma membrane repair is coming of age. Mirroring human adolescence, the field shows at the same time signs of maturity and significant uncertainty, confusion and skepticism. Here we discuss concepts that emerged from experimental data over the years, some of which are solidly established while others are still subject to different interpretations. The firmly established concepts include the critical requirement for Ca(2+) in wound repair, and the role of rapid exocytosis of intracellular vesicles. Lysosomes are being increasingly recognized as the major vesicles involved in injury-induced exocytosis in many cell types, as a growing number of laboratories detect markers for these organelles on the cell surface and lysosomal hydrolases in the supernatant of wounded cells. The more recent observation of massive endocytosis following Ca(2+)-triggered exocytosis initially came as a surprise, but this finding is also being increasingly reported by different groups, shifting the discussion to the mechanisms by which endocytosis promotes repair, and whether it operates or not in parallel with the shedding of membrane blebs. We discuss how the abundant intracellular vesicles that undergo homotypic fusion close to wound sites, previously interpreted as exocytic membrane patches, actually acquire extracellular tracers demonstrating their endocytic origin. We also suggest that an initial, temporary patch that prevents cytosol loss until the bilayer is restored might result not from vesicular fusion, but from rapid Ca(2+)-dependent crosslinking and aggregation of cytosolic proteins. Finally, we propose that cell surface remodeling, orchestrated by the extracellular release of lysosomal hydrolases and perhaps also cytosolic molecules, may represent a key aspect of the plasma membrane repair mechanism that has received little attention so far.
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Affiliation(s)
- N W Andrews
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.
| | - M Corrotte
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - T Castro-Gomes
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
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36
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Approaches for plasma membrane wounding and assessment of lysosome-mediated repair responses. Methods Cell Biol 2015; 126:139-58. [PMID: 25665445 DOI: 10.1016/bs.mcb.2014.11.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Rapid plasma membrane repair is essential to restore cellular homeostasis and improve cell survival after injury. Several mechanisms for plasma membrane repair have been proposed, including formation of an intracellular vesicle patch, reduction of plasma membrane tension, lesion removal by endocytosis, and/or shedding of the wounded membrane. Under all conditions studied to date, plasma membrane repair is strictly dependent on the entry of calcium into cells, from the extracellular medium. Calcium-dependent exocytosis of lysosomes is an important early step in the plasma membrane repair process, and defects in plasma membrane repair have been observed in cells carrying mutations responsible for serious lysosomal diseases, such as Chediak-Higashi (Huynh, Roth, Ward, Kaplan, & Andrews, 2004) and Niemann-Pick Disease type A (Tam et al., 2010). A functional role for release of the lysosomal enzyme acid sphingomyelinase, which generates ceramide on the cell surface and triggers endocytosis, has been described (Corrotte et al., 2013; Tam et al., 2010). Therefore, procedures for measuring the extent of lysosomal fusion with the plasma membrane of wounded cells are important indicators of the cellular repair response. The importance of carefully selecting the methodology for experimental plasma membrane injury, in order not to adversely impact the membrane repair machinery, is becoming increasingly apparent. Here, we describe physiologically relevant methods to induce different types of cellular wounds, and sensitive assays to measure the ability of cells to secrete lysosomes and reseal their plasma membrane.
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37
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Qin C, Yang YH, May L, Gao X, Stewart AG, Tu Y, Woodman OL, Ritchie RH. Cardioprotective potential of annexin-A1 mimetics in myocardial infarction. Pharmacol Ther 2014; 148:47-65. [PMID: 25460034 DOI: 10.1016/j.pharmthera.2014.11.012] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 11/14/2014] [Indexed: 12/15/2022]
Abstract
Myocardial infarction (MI) and its resultant heart failure remains a major cause of death in the world. The current treatments for patients with MI are revascularization with thrombolytic agents or interventional procedures. These treatments have focused on restoring blood flow to the ischemic tissue to prevent tissue necrosis and preserve organ function. The restoration of blood flow after a period of ischemia, however, may elicit further myocardial damage, called reperfusion injury. Pharmacological interventions, such as antioxidant and Ca(2+) channel blockers, have shown premises in experimental settings; however, clinical studies have shown limited success. Thus, there is a need for the development of novel therapies to treat reperfusion injury. The therapeutic potential of glucocorticoid-regulated anti-inflammatory mediator annexin-A1 (ANX-A1) has recently been recognized in a range of systemic inflammatory disorders. ANX-A1 binds to and activates the family of formyl peptide receptors (G protein-coupled receptor family) to inhibit neutrophil activation, migration and infiltration. Until recently, studies on the cardioprotective actions of ANX-A1 and its peptide mimetics (Ac2-26, CGEN-855A) have largely focused on its anti-inflammatory effects as a mechanism of preserving myocardial viability following I-R injury. Our laboratory provided the first evidence of the direct protective action of ANX-A1 on myocardium, independent of inflammatory cells in vitro. We now review the potential for ANX-A1 based therapeutics to be seen as a "triple shield" therapy against myocardial I-R injury, limiting neutrophil infiltration and preserving both cardiomyocyte viability and contractile function. This novel therapy may thus represent a valuable clinical approach to improve outcome after MI.
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Affiliation(s)
- Chengxue Qin
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia; Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, Australia
| | - Yuan H Yang
- Centre for Inflammatory Diseases Monash University and Monash Medical Centre, Clayton, Victoria, Australia
| | - Lauren May
- Department of Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Xiaoming Gao
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Alastair G Stewart
- Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, Australia
| | - Yan Tu
- Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, Australia
| | - Owen L Woodman
- School of Medical Sciences, RMIT University, Bundoora 3083, Victoria, Australia
| | - Rebecca H Ritchie
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia; Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, Australia; Department of Medicine, Monash University, Clayton, Victoria, Australia.
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38
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Draeger A, Schoenauer R, Atanassoff AP, Wolfmeier H, Babiychuk EB. Dealing with damage: plasma membrane repair mechanisms. Biochimie 2014; 107 Pt A:66-72. [PMID: 25183513 DOI: 10.1016/j.biochi.2014.08.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/15/2014] [Indexed: 12/22/2022]
Abstract
Eukaryotic cells have developed repair mechanisms, which allow them to reseal their membrane in order to prevent the efflux of cytoplasmic constituents and the uncontrolled influx of calcium. After injury, the Ca(2+)-concentration gradient fulfils a dual function: it provides guidance cues for the repair machinery and directly activates the molecules, which have a repair function. Depending on the nature of injury, the morphology of the cell and the severity of injury, the membrane resealing can be effected by lysosomal exocytosis, microvesicle shedding or a combination of both. Likewise, exocytosis is often followed by the endocytic uptake of lesions. Additionally, since plasmalemmal resealing must be attempted, even after extensive injury in order to prevent cell lysis, the restoration of membrane integrity can be achieved by ceramide-driven invagination of the lipid bilayer, during which the cell is prepared for apoptotic disposal. Plasmalemmal injury can be contained by a surfeit of plasma membrane, which serves as a trap for toxic substances: either passively by an abundance of cellular protrusions, or actively by membrane blebbing.
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Affiliation(s)
- Annette Draeger
- Department of Cell Biology, Institute of Anatomy, University of Bern, Baltzerstr. 2, 3012 Bern, Switzerland.
| | - Roman Schoenauer
- Department of Cell Biology, Institute of Anatomy, University of Bern, Baltzerstr. 2, 3012 Bern, Switzerland
| | - Alexander P Atanassoff
- Department of Cell Biology, Institute of Anatomy, University of Bern, Baltzerstr. 2, 3012 Bern, Switzerland
| | - Heidi Wolfmeier
- Department of Cell Biology, Institute of Anatomy, University of Bern, Baltzerstr. 2, 3012 Bern, Switzerland
| | - Eduard B Babiychuk
- Department of Cell Biology, Institute of Anatomy, University of Bern, Baltzerstr. 2, 3012 Bern, Switzerland
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39
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Andrews NW, Almeida PE, Corrotte M. Damage control: cellular mechanisms of plasma membrane repair. Trends Cell Biol 2014; 24:734-42. [PMID: 25150593 DOI: 10.1016/j.tcb.2014.07.008] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 07/29/2014] [Accepted: 07/31/2014] [Indexed: 02/06/2023]
Abstract
When wounded, eukaryotic cells reseal in a few seconds. Ca(2+) influx induces exocytosis of lysosomes, a process previously thought to promote repair by 'patching' wounds. New evidence suggests that resealing involves direct wound removal. Exocytosis of lysosomal acid sphingomyelinase (ASM) triggers endocytosis of lesions followed by intracellular degradation. Characterization of injury-induced endosomes revealed a role for caveolae, sphingolipid-enriched plasma membrane invaginations that internalize toxin pores and are abundant in mechanically stressed cells. These findings provide a novel mechanistic explanation for the muscle pathology associated with mutations in caveolar proteins. Membrane remodeling by the ESCRT complex was also recently shown to participate in small-wound repair, emphasizing that cell resealing involves previously unrecognized mechanisms for lesion removal that are distinct from the patch model.
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Affiliation(s)
- Norma W Andrews
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA.
| | - Patricia E Almeida
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA; Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Matthias Corrotte
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA
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40
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Ciechonska M, Key T, Duncan R. Efficient reovirus- and measles virus-mediated pore expansion during syncytium formation is dependent on annexin A1 and intracellular calcium. J Virol 2014; 88:6137-47. [PMID: 24648446 PMCID: PMC4093853 DOI: 10.1128/jvi.00121-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 03/11/2014] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Orthoreovirus fusion-associated small transmembrane (FAST) proteins are dedicated cell-cell fusogens responsible for multinucleated syncytium formation and are virulence determinants of the fusogenic reoviruses. While numerous studies on the FAST proteins and enveloped-virus fusogens have delineated steps involved in membrane fusion and pore formation, little is known about the mechanics of pore expansion needed for syncytiogenesis. We now report that RNA interference (RNAi) knockdown of annexin A1 (AX1) expression dramatically reduced both reptilian reovirus p14 and measles virus F and H protein-mediated pore expansion during syncytiogenesis but had no effect on pore formation. A similar effect was obtained by chelating intracellular calcium, which dramatically decreased syncytiogenesis in the absence of detectable effects on p14-induced pore formation. Coimmunoprecipitation revealed calcium-dependent interaction between AX1 and p14 or measles virus F and H proteins, and fluorescence resonance energy transfer (FRET) demonstrated calcium-dependent p14-AX1 interactions in cellulo. Furthermore, antibody inhibition of extracellular AX1 had no effect on p14-induced syncytium formation but did impair cell-cell fusion mediated by the endogenous muscle cell fusion machinery in C2C12 mouse myoblasts. AX1 can therefore exert diverse, fusogen-specific effects on cell-cell fusion, functioning as an extracellular mediator of differentiation-dependent membrane fusion or as an intracellular promoter of postfusion pore expansion and syncytium formation following virus-mediated cell-cell fusion. IMPORTANCE Numerous enveloped viruses and nonenveloped fusogenic orthoreoviruses encode membrane fusion proteins that induce syncytium formation, which has been linked to viral pathogenicity. Considerable insights into the mechanisms of membrane fusion have been obtained, but processes that drive postfusion expansion of fusion pores to generate syncytia are poorly understood. This study identifies intracellular calcium and annexin A1 (AX1) as key factors required for efficient pore expansion during syncytium formation mediated by the reptilian reovirus p14 and measles virus F and H fusion protein complexes. Involvement of intracellular AX1 in syncytiogenesis directly correlates with a requirement for intracellular calcium in p14-AX1 interactions and pore expansion but not membrane fusion and pore formation. This is the first demonstration that intracellular AX1 is involved in pore expansion, which suggests that the AX1 pathway may be a common host cell response needed to resolve virus-induced cell-cell fusion pores.
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Affiliation(s)
- Marta Ciechonska
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Tim Key
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Roy Duncan
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
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41
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Hoque M, Rentero C, Cairns R, Tebar F, Enrich C, Grewal T. Annexins — Scaffolds modulating PKC localization and signaling. Cell Signal 2014; 26:1213-25. [DOI: 10.1016/j.cellsig.2014.02.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 02/22/2014] [Indexed: 12/15/2022]
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42
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Atanassoff AP, Wolfmeier H, Schoenauer R, Hostettler A, Ring A, Draeger A, Babiychuk EB. Microvesicle shedding and lysosomal repair fulfill divergent cellular needs during the repair of streptolysin O-induced plasmalemmal damage. PLoS One 2014; 9:e89743. [PMID: 24587004 PMCID: PMC3931818 DOI: 10.1371/journal.pone.0089743] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 01/23/2014] [Indexed: 12/13/2022] Open
Abstract
Pathogenic bacteria secrete pore-forming toxins that permeabilize the plasma membrane of host cells. Nucleated cells possess protective mechanisms that repair toxin-damaged plasmalemma. Currently two putative repair scenarios are debated: either the isolation of the damaged membrane regions and their subsequent expulsion as microvesicles (shedding) or lysosome-dependent repair might allow the cell to rid itself of its toxic cargo and prevent lysis. Here we provide evidence that both mechanisms operate in tandem but fulfill diverse cellular needs. The prevalence of the repair strategy varies between cell types and is guided by the severity and the localization of the initial toxin-induced damage, by the morphology of a cell and, most important, by the incidence of the secondary mechanical damage. The surgically precise action of microvesicle shedding is best suited for the instant elimination of individual toxin pores, whereas lysosomal repair is indispensable for mending of self-inflicted mechanical injuries following initial plasmalemmal permeabilization by bacterial toxins. Our study provides new insights into the functioning of non-immune cellular defenses against bacterial pathogens.
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Affiliation(s)
| | - Heidi Wolfmeier
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Roman Schoenauer
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Andrea Hostettler
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Avi Ring
- Department of Protection, Norwegian Defence Research Establishment, Kjeller, Norway
| | - Annette Draeger
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Eduard B. Babiychuk
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
- * E-mail:
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43
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Castro BM, Prieto M, Silva LC. Ceramide: a simple sphingolipid with unique biophysical properties. Prog Lipid Res 2014; 54:53-67. [PMID: 24513486 DOI: 10.1016/j.plipres.2014.01.004] [Citation(s) in RCA: 266] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/29/2014] [Accepted: 01/29/2014] [Indexed: 02/06/2023]
Abstract
Ceramides are involved in a variety of cellular processes and in disease. Their biological functions are thought to depend on ceramides' unique biophysical properties, which promote strong alterations of cell membrane properties and consequent triggering of signaling events. Over the last decades, efforts were made to understand the impact of ceramide on membrane biophysical features. Several studies, performed in a multitude of membrane models, address ceramides' specific interactions, the effect of their acyl chain structure and the influence of membrane lipid composition and properties on ceramide biophysical outcome. In this review, a rationale for the multiple and complex changes promoted by ceramide is provided, highlighting, on a comprehensive and critical manner, the interactions between ceramides and specific lipids and/or lipid phases. Focus is also given to the interplay between ceramide and cholesterol, particularly in lipid raft-mimicking mixtures, an issue of intense debate due to the urgent need to understand the biophysical impact of ceramide formation in models resembling the cell membrane. The implications of ceramide-induced biophysical changes on lipid-protein interactions and cell signaling are also discussed, together with the emerging evidence for the existence of ceramide-gel like domains in cellular membranes.
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Affiliation(s)
- Bruno M Castro
- Centro de Química-Física Molecular and Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, Universidade de Lisboa, Complexo I, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Manuel Prieto
- Centro de Química-Física Molecular and Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, Universidade de Lisboa, Complexo I, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Liana C Silva
- iMed.UL - Research Institute for Medicines and Pharmaceutical Sciences, Faculdade de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal.
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44
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Annexin-phospholipid interactions. Functional implications. Int J Mol Sci 2013; 14:2652-83. [PMID: 23358253 PMCID: PMC3588008 DOI: 10.3390/ijms14022652] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 01/12/2013] [Accepted: 01/15/2013] [Indexed: 02/03/2023] Open
Abstract
Annexins constitute an evolutionary conserved multigene protein superfamily characterized by their ability to interact with biological membranes in a calcium dependent manner. They are expressed by all living organisms with the exception of certain unicellular organisms. The vertebrate annexin core is composed of four (eight in annexin A6) homologous domains of around 70 amino acids, with the overall shape of a slightly bent ring surrounding a central hydrophilic pore. Calcium- and phospholipid-binding sites are located on the convex side while the N-terminus links domains I and IV on the concave side. The N-terminus region shows great variability in length and amino acid sequence and it greatly influences protein stability and specific functions of annexins. These proteins interact mainly with acidic phospholipids, such as phosphatidylserine, but differences are found regarding their affinity for lipids and calcium requirements for the interaction. Annexins are involved in a wide range of intra- and extracellular biological processes in vitro, most of them directly related with the conserved ability to bind to phospholipid bilayers: membrane trafficking, membrane-cytoskeleton anchorage, ion channel activity and regulation, as well as antiinflammatory and anticoagulant activities. However, the in vivo physiological functions of annexins are just beginning to be established.
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45
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Abstract
The perforation of the plasmalemma by pore-forming toxins causes an influx of Ca(2+) and an efflux of cytoplasmic proteins. In order to ensure cellular survival, lesions have to be identified, plugged and removed from the membrane. The Ca(2+)-driven fusion of lysosomes with the plasma membrane leads to hydrolysis of sphingomyelin by acid sphingomyelinase and a formation of ceramide platforms in the outer leaflet of the lipid bilayer. We propose that the negative curvature, promoted by tighter packing of lipids in the outer layer, leads to an inward vesiculation of the damaged area for its endocytotic uptake and internal degradation. In contrast, the activation of neutral sphingomyelinase triggers the production of ceramide within the inner leaflet of the lipid bilayer, thereby promoting an outward curvature, which enables the cell to shed the membrane-containing toxin pore into the extracellular space. In this process, ceramide is supported by members of the annexin protein family which act as Ca(2+) sensors and as membrane fusion agents.
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Affiliation(s)
- Annette Draeger
- Department of Cell Biology, University of Bern, Bern, Switzerland.
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46
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Abstract
One crucial barrier to progress in the treatment of cancer has been the inability to control the balance between cell proliferation and apoptosis: enter ceramide. Discoveries over the past 15 years have elevated this sphingolipid to the lofty position of a regulator of cell fate. Ceramide, it turns out, is a powerful tumour suppressor, potentiating signalling events that drive apoptosis, autophagic responses and cell cycle arrest. However, defects in ceramide generation and metabolism in cancer cells contribute to tumour cell survival and resistance to chemotherapy. This Review focuses on ceramide signalling and the targeting of specific metabolic junctures to amplify the tumour suppressive activities of ceramide. The potential of ceramide-based therapeutics in the treatment of cancer is also discussed.
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Affiliation(s)
- Samy A F Morad
- Department of Experimental Therapeutics, John Wayne Cancer Institute at Saint John's Health Center, 2200 Santa Monica Boulevard, Santa Monica, California 90404, USA.
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47
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Illien F, Piao HR, Coué M, di Marco C, Ayala-Sanmartin J. Lipid organization regulates annexin A2 Ca2+-sensitivity for membrane bridging and its modulator effects on membrane fluidity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:2892-900. [DOI: 10.1016/j.bbamem.2012.07.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/03/2012] [Accepted: 07/17/2012] [Indexed: 10/28/2022]
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48
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Reverter M, Rentero C, de Muga SV, Alvarez-Guaita A, Mulay V, Cairns R, Wood P, Monastyrskaya K, Pol A, Tebar F, Blasi J, Grewal T, Enrich C. Cholesterol transport from late endosomes to the Golgi regulates t-SNARE trafficking, assembly, and function. Mol Biol Cell 2012; 22:4108-23. [PMID: 22039070 PMCID: PMC3204072 DOI: 10.1091/mbc.e11-04-0332] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
This study shows that impaired cholesterol egress from late endosomes in cells with high annexin A6 levels is associated with altered soluble N-ethylmaleimide–sensitive fusion protein 23 (SNAP23) and syntaxin-4 cellular distribution and assembly and accumulation in Golgi membranes. This correlates with reduced secretion of cargo along the constitutive and SNAP23/syntaxin-4–dependent secretory pathway. Cholesterol regulates plasma membrane (PM) association and functioning of syntaxin-4 and soluble N-ethylmaleimide-sensitive fusion protein 23 (SNAP23) in the secretory pathway. However, the molecular mechanism and cellular cholesterol pools that determine the localization and assembly of these target membrane SNAP receptors (t-SNAREs) are largely unknown. We recently demonstrated that high levels of annexin A6 (AnxA6) induce accumulation of cholesterol in late endosomes, thereby reducing cholesterol in the Golgi and PM. This leads to an impaired supply of cholesterol needed for cytosolic phospholipase A2 (cPLA2) to drive Golgi vesiculation and caveolin transport to the cell surface. Using AnxA6-overexpressing cells as a model for cellular cholesterol imbalance, we identify impaired cholesterol egress from late endosomes and diminution of Golgi cholesterol as correlating with the sequestration of SNAP23/syntaxin-4 in Golgi membranes. Pharmacological accumulation of late endosomal cholesterol and cPLA2 inhibition induces a similar phenotype in control cells with low AnxA6 levels. Ectopic expression of Niemann-Pick C1 (NPC1) or exogenous cholesterol restores the location of SNAP23 and syntaxin-4 within the PM. Importantly, AnxA6-mediated mislocalization of these t-SNAREs correlates with reduced secretion of cargo via the SNAP23/syntaxin-4–dependent constitutive exocytic pathway. We thus conclude that inhibition of late endosomal export and Golgi cholesterol depletion modulate t-SNARE localization and functioning along the exocytic pathway.
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Affiliation(s)
- Meritxell Reverter
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Universitat de Barcelona, 08036 Barcelona, Spain
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49
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Reverter M, Rentero C, de Muga SV, Alvarez-Guaita A, Mulay V, Cairns R, Wood P, Monastyrskaya K, Pol A, Tebar F, Blasi J, Grewal T, Enrich C. Cholesterol transport from late endosomes to the Golgi regulates t-SNARE trafficking, assembly, and function. Mol Biol Cell 2011. [DOI: 10.1091/mbc.e11-04-0332r] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Cholesterol regulates plasma membrane (PM) association and functioning of syntaxin-4 and soluble N-ethylmaleimide-sensitive fusion protein 23 (SNAP23) in the secretory pathway. However, the molecular mechanism and cellular cholesterol pools that determine the localization and assembly of these target membrane SNAP receptors (t-SNAREs) are largely unknown. We recently demonstrated that high levels of annexin A6 (AnxA6) induce accumulation of cholesterol in late endosomes, thereby reducing cholesterol in the Golgi and PM. This leads to an impaired supply of cholesterol needed for cytosolic phospholipase A2(cPLA2) to drive Golgi vesiculation and caveolin transport to the cell surface. Using AnxA6-overexpressing cells as a model for cellular cholesterol imbalance, we identify impaired cholesterol egress from late endosomes and diminution of Golgi cholesterol as correlating with the sequestration of SNAP23/syntaxin-4 in Golgi membranes. Pharmacological accumulation of late endosomal cholesterol and cPLA2inhibition induces a similar phenotype in control cells with low AnxA6 levels. Ectopic expression of Niemann-Pick C1 (NPC1) or exogenous cholesterol restores the location of SNAP23 and syntaxin-4 within the PM. Importantly, AnxA6-mediated mislocalization of these t-SNAREs correlates with reduced secretion of cargo via the SNAP23/syntaxin-4–dependent constitutive exocytic pathway. We thus conclude that inhibition of late endosomal export and Golgi cholesterol depletion modulate t-SNARE localization and functioning along the exocytic pathway.
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Affiliation(s)
- Meritxell Reverter
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Carles Rentero
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Sandra Vilà de Muga
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Anna Alvarez-Guaita
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Vishwaroop Mulay
- Faculty of Pharmacy, University of Sydney, Sydney, NSW 2006, Australia
| | - Rose Cairns
- Faculty of Pharmacy, University of Sydney, Sydney, NSW 2006, Australia
| | - Peta Wood
- Faculty of Pharmacy, University of Sydney, Sydney, NSW 2006, Australia
| | - Katia Monastyrskaya
- Urology Research Laboratory, Department of Clinical Research, University of Bern, 3000 Bern 9, Switzerland
| | - Albert Pol
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
| | - Francesc Tebar
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Joan Blasi
- Department of Pathology and Experimental Therapeutics, IDIBELL–University of Barcelona, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Thomas Grewal
- Faculty of Pharmacy, University of Sydney, Sydney, NSW 2006, Australia
| | - Carlos Enrich
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
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50
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Magenau A, Benzing C, Proschogo N, Don AS, Hejazi L, Karunakaran D, Jessup W, Gaus K. Phagocytosis of IgG-coated polystyrene beads by macrophages induces and requires high membrane order. Traffic 2011; 12:1730-43. [PMID: 21883764 DOI: 10.1111/j.1600-0854.2011.01272.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biochemical composition and biophysical properties of cell membranes are hypothesized to affect cellular processes such as phagocytosis. Here, we examined the plasma membranes of murine macrophage cell lines during the early stages of uptake of immunoglobulin G (IgG)-coated polystyrene particles. We found that the plasma membrane undergoes rapid actin-independent condensation to form highly ordered phagosomal membranes, the biophysical hallmark of lipid rafts. Surprisingly, these membranes are depleted of cholesterol and enriched in sphingomyelin and ceramide. Inhibition of sphingomyelinase activity impairs membrane condensation, F-actin accumulation at phagocytic cups and particle uptake. Switching phagosomal membranes to a cholesterol-rich environment had no effect on membrane condensation and the rate of phagocytosis. In contrast, preventing membrane condensation with the oxysterol 7-ketocholesterol, even in the presence of ceramide, blocked F-actin dissociation from nascent phagosomes and particle uptake. In conclusion, our results suggest that ordered membranes function to co-ordinate F-actin remodelling and that the biophysical properties of phagosomal membranes are essential for phagocytosis.
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Affiliation(s)
- Astrid Magenau
- Centre for Vascular Research, University of New South Wales, Sydney, Australia
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