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Wei J, Zhang M, Wang X, Yang K, Xiao Q, Zhu X, Pan X. Role of cardiolipin in regulating and treating atherosclerotic cardiovascular diseases. Eur J Pharmacol 2024; 979:176853. [PMID: 39067567 DOI: 10.1016/j.ejphar.2024.176853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/10/2024] [Accepted: 07/24/2024] [Indexed: 07/30/2024]
Abstract
Cardiovascular diseases, mainly caused by atherosclerosis, are the leading causes of morbidity and mortality worldwide. Despite the discrepancies in clinical manifestations between different abnormalities, atherosclerosis shares similar pathophysiological processes, such as mitochondrial dysfunction. Cardiolipin (CL) is a conserved mitochondria-specific lipid that contributes to the cristae structure of the inner mitochondrial membrane (IMM). Alterations in the CL, including oxidative modification, reduced quantity, and abnormal localization, contribute to the onset and progression of atherosclerosis. In this review, we summarize the knowledge that CL is involved in the pathogenesis of atherosclerosis. On the one hand, CL and its oxidative modification promote the progression of atherosclerosis via several mechanisms, including oxidative stress, apoptosis, and inflammation in response to stress. On the other hand, CL externalizes to the outer mitochondrial membrane (OMM) and acts as the pivotal "eat-me" signal in mitophagy, removing dysfunctional mitochondria and safeguarding against the progression of atherosclerosis. Given the imbalance between proatherogenic and antiatherogenic effects, we provide our understanding of the roles of the CL and its oxidative modification in atherosclerotic cardiovascular diseases, in addition to potential therapeutic strategies aimed at restoring the CL. Briefly, CL is far more than a structural IMM lipid; broader significances of the evolutionarily conserved lipid need to be explored.
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Affiliation(s)
- Jin Wei
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Meng Zhang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xia Wang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Kaiying Yang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Qi Xiao
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China.
| | - Xiaoyan Zhu
- Department of Critical Care Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China.
| | - Xudong Pan
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China.
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2
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Miao R, Jiang C, Chang WY, Zhang H, An J, Ho F, Chen P, Zhang H, Junqueira C, Amgalan D, Liang FG, Zhang J, Evavold CL, Hafner-Bratkovič I, Zhang Z, Fontana P, Xia S, Waldeck-Weiermair M, Pan Y, Michel T, Bar-Peled L, Wu H, Kagan JC, Kitsis RN, Zhang P, Liu X, Lieberman J. Gasdermin D permeabilization of mitochondrial inner and outer membranes accelerates and enhances pyroptosis. Immunity 2023; 56:2523-2541.e8. [PMID: 37924812 PMCID: PMC10872579 DOI: 10.1016/j.immuni.2023.10.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 08/30/2023] [Accepted: 10/06/2023] [Indexed: 11/06/2023]
Abstract
Gasdermin D (GSDMD)-activated inflammatory cell death (pyroptosis) causes mitochondrial damage, but its underlying mechanism and functional consequences are largely unknown. Here, we show that the N-terminal pore-forming GSDMD fragment (GSDMD-NT) rapidly damaged both inner and outer mitochondrial membranes (OMMs) leading to reduced mitochondrial numbers, mitophagy, ROS, loss of transmembrane potential, attenuated oxidative phosphorylation (OXPHOS), and release of mitochondrial proteins and DNA from the matrix and intermembrane space. Mitochondrial damage occurred as soon as GSDMD was cleaved prior to plasma membrane damage. Mitochondrial damage was independent of the B-cell lymphoma 2 family and depended on GSDMD-NT binding to cardiolipin. Canonical and noncanonical inflammasome activation of mitochondrial damage, pyroptosis, and inflammatory cytokine release were suppressed by genetic ablation of cardiolipin synthase (Crls1) or the scramblase (Plscr3) that transfers cardiolipin to the OMM. Phospholipid scramblase-3 (PLSCR3) deficiency in a tumor compromised pyroptosis-triggered anti-tumor immunity. Thus, mitochondrial damage plays a critical role in pyroptosis.
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Affiliation(s)
- Rui Miao
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
| | - Cong Jiang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; Key Laboratory of RNA Science and Engineering, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai 200031, China
| | - Winston Y Chang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Haiwei Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Jinsu An
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Felicia Ho
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Pengcheng Chen
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai 200031, China
| | - Han Zhang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; Key Laboratory of RNA Science and Engineering, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai 200031, China
| | - Caroline Junqueira
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG 30190-009, Brazil
| | - Dulguun Amgalan
- Departments of Medicine and Cell Biology, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Felix G Liang
- Departments of Medicine and Cell Biology, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Junbing Zhang
- Center for Cancer Research, Massachusetts General Hospital and Department of Medicine, Harvard Medical School, Boston, MA 02129, USA
| | - Charles L Evavold
- Ragon Institute of Mass General, MIT and Harvard, Cambridge, MA 02139, USA
| | - Iva Hafner-Bratkovič
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA; Department of Synthetic Biology and Immunology, National Institute of Chemistry and EN-FIST Centre of Excellence and Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Zhibin Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Pietro Fontana
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Shiyu Xia
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Markus Waldeck-Weiermair
- Brigham and Women's Hospital, Department of Medicine, Cardiovascular Division, Harvard Medical School, Boston, MA 02115, USA
| | - Youdong Pan
- Department of Dermatology and Harvard Skin Disease Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Thomas Michel
- Brigham and Women's Hospital, Department of Medicine, Cardiovascular Division, Harvard Medical School, Boston, MA 02115, USA
| | - Liron Bar-Peled
- Center for Cancer Research, Massachusetts General Hospital and Department of Medicine, Harvard Medical School, Boston, MA 02129, USA
| | - Hao Wu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Jonathan C Kagan
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Richard N Kitsis
- Departments of Medicine and Cell Biology, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Peng Zhang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China.
| | - Xing Liu
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai 200031, China.
| | - Judy Lieberman
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
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3
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Garg M, Johri S, Chakraborty K. Immunomodulatory role of mitochondrial DAMPs: a missing link in pathology? FEBS J 2023; 290:4395-4418. [PMID: 35731715 DOI: 10.1111/febs.16563] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/18/2022] [Accepted: 06/21/2022] [Indexed: 12/01/2022]
Abstract
In accordance with the endosymbiotic theory, mitochondrial components bear characteristic prokaryotic signatures, which act as immunomodulatory molecules when released into the extramitochondrial compartment. These endogenous immune triggers, called mitochondrial damage-associated molecular patterns (mtDAMPs), have been implicated in the pathogenesis of various diseases, yet their role remains largely unexplored. In this review, we summarise the available literature on mtDAMPs in diseases, with a special focus on respiratory diseases. We highlight the need to bolster mtDAMP research using a multipronged approach, to study their effect on specific cell types, receptors and machinery in pathologies. We emphasise the lacunae in the current understanding of mtDAMPs, particularly in their cellular release and the chemical modifications they undergo. Finally, we conclude by proposing additional effects of mtDAMPs in diseases, specifically their role in modulating the immune system.
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Affiliation(s)
- Mayank Garg
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Saumya Johri
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Krishnendu Chakraborty
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
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Chernyshova DN, Tyulin AA, Ostroumova OS, Efimova SS. Discovery of the Potentiator of the Pore-Forming Ability of Lantibiotic Nisin: Perspectives for Anticancer Therapy. MEMBRANES 2022; 12:membranes12111166. [PMID: 36422158 PMCID: PMC9694817 DOI: 10.3390/membranes12111166] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 05/12/2023]
Abstract
This study was focused on the action of lantibiotic nisin on the phospholipid membranes. Nisin did not produce ion-permeable pores in the membranes composed of DOPC or DOPE. The introduction of DOPS into bilayer lipid composition led to a decrease in the threshold detergent concentration of nisin. An addition of nisin to DOPG- and TOCL-enriched bilayers caused the formation of well-defined ion pores of various conductances. The transmembrane macroscopic current increased with the second power of the lantibiotic aqueous concentration, suggesting that the dimer of nisin was at least involved in the formation of conductive subunit. The pore-forming ability of lantibiotic decreased in the series: DOPC/TOCL ≈ DOPE/TOCL >> DOPC/DOPG ≥ DOPE/DOPG. The preferential interaction of nisin to cardiolipin-enriched bilayers might explain its antitumor activity by pore-formation in mitochondrial membranes. Small natural molecules, phloretin and capsaicin, were found to potentiate the membrane activity of nisin in the TOCL-containing membranes. The effect was referred to as changes in the membrane boundary potential at the adsorption of small molecules. We concluded that the compounds diminishing the membrane boundary potential should be considered as the potentiator of the nisin pore-forming ability that can be used to develop innovative formulations for anticancer therapy.
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Rusin A, Li M, Cocchetto A, Seymour C, Mothersill C. Radiation exposure and mitochondrial insufficiency in chronic fatigue and immune dysfunction syndrome. Med Hypotheses 2021; 154:110647. [PMID: 34358921 DOI: 10.1016/j.mehy.2021.110647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 04/19/2021] [Accepted: 07/25/2021] [Indexed: 12/13/2022]
Abstract
Chronic fatigue and Immune Dysfunction Syndrome (CFIDS) is a heterogeneous disease that may be promoted by various environmental stressors, including viral infection, toxin uptake, and ionizing radiation exposure. Previous studies have identified mitochondrial dysfunction in CFIDS patients, including modulation of mitochondrial respiratory chain activity, deletions in the mitochondrial genome, and upregulation of reactive oxygen species (ROS). This paper focuses on radiation effects and hypothesizes that CFIDS is primarily caused by stressor-induced mitochondrial metabolic insufficiency, which results in decreased energy production and anabolic metabolites required for normal cellular metabolism. Furthermore, tissues neighbouring or distant from directly perturbed tissues compensate for this dysfunction, which causes symptoms associated with CFIDS. This hypothesis is justified by reviewing the links between radiation exposure and CFIDS, cancer, immune dysfunction, and induction of oxidative stress. Moreover, the relevance of mitochondria in cellular responses to radiation and metabolism are discussed and putative mitochondrial biomarkers for CFIDS are introduced. Implications for diagnosis are then described, including a potential urine assay and PCR test for mitochondrial genome mutations. Finally, future research needs are offered with an emphasis on where rapid progress may be made to assist the afflicted.
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Affiliation(s)
- Andrej Rusin
- Department of Biology, McMaster University, Hamilton, ON Canada.
| | - Megan Li
- Department of Physics and Astronomy, McMaster University, Department of Physics and Astronomy, McMaster University, Hamilton, ON Canada
| | - Alan Cocchetto
- National CFIDS Foundation Inc., 103 Aletha Road, Needham, MA USA
| | - Colin Seymour
- Department of Biology, McMaster University, Hamilton, ON Canada
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TTAPE-Me dye is not selective to cardiolipin and binds to common anionic phospholipids nonspecifically. Biophys J 2021; 120:3776-3786. [PMID: 34280369 DOI: 10.1016/j.bpj.2021.06.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 06/09/2021] [Accepted: 06/24/2021] [Indexed: 11/21/2022] Open
Abstract
Identification, visualization, and quantitation of cardiolipin (CL) in biological membranes is of great interest because of the important structural and physiological roles of this lipid. Selective fluorescent detection of CL using noncovalently bound fluorophore 1,1,2,2-tetrakis[4-(2-trimethylammonioethoxy)-phenylethene (TTAPE-Me) has been recently proposed. However, this dye was only tested on wild-type mitochondria or liposomes containing negligible amounts of other anionic lipids, such as phosphatidylglycerol (PG) and phosphatidylserine (PS). No clear preference of TTAPE-Me for binding to CL compared to PG and PS was found in our experiments on artificial liposomes, Escherichia coli inside-out vesicles, or Saccharomyces cerevisiae mitochondria in vitro or in situ, respectively. The shapes of the emission spectra for these anionic phospholipids were also found to be indistinguishable. Thus, TTAPE-Me is not suitable for detection, visualization, and localization of CL in the presence of other anionic lipids present in substantial physiological amounts. Our experiments and complementary molecular dynamics simulations suggest that fluorescence intensity of TTAPE-Me is regulated by dynamic equilibrium between emitting dye aggregates, stabilized by unspecific but thermodynamically favorable electrostatic interactions with anionic lipids, and nonemitting dye monomers. These results should be taken into consideration when interpreting past and future results of CL detection and localization studies with this probe in vitro and in vivo. Provided methodology emphasizes minimal experimental requirements, which should be considered as a guideline during the development of novel lipid-specific probes.
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Structure and function at the lipid-protein interface of a pentameric ligand-gated ion channel. Proc Natl Acad Sci U S A 2021; 118:2100164118. [PMID: 34083441 DOI: 10.1073/pnas.2100164118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Although it has long been proposed that membrane proteins may contain tightly bound lipids, their identity, the structure of their binding sites, and their functional and structural relevance have remained elusive. To some extent, this is because tightly bound lipids are often located at the periphery of proteins, where the quality of density maps is usually poorer, and because they may be outcompeted by detergent molecules used during standard purification procedures. As a step toward characterizing natively bound lipids in the superfamily of pentameric ligand-gated ion channels (pLGICs), we applied single-particle cryogenic electron microscopy to fragments of native membrane obtained in the complete absence of detergent-solubilization steps. Because of the heterogeneous lipid composition of membranes in the secretory pathway of eukaryotic cells, we chose to study a bacterial pLGIC (ELIC) expressed in Escherichia coli's inner membrane. We obtained a three-dimensional reconstruction of unliganded ELIC (2.5-Å resolution) that shows clear evidence for two types of tightly bound lipid at the protein-bulk-membrane interface. One of them was consistent with a "regular" diacylated phospholipid, in the cytoplasmic leaflet, whereas the other one was consistent with the tetra-acylated structure of cardiolipin, in the periplasmic leaflet. Upon reconstitution in E. coli polar-lipid bilayers, ELIC retained the functional properties characteristic of members of this superfamily, and thus, the fitted atomic model is expected to represent the (long-debated) unliganded-closed, "resting" conformation of this ion channel. Notably, the addition of cardiolipin to phosphatidylcholine membranes restored the ion-channel activity that is largely lost in phosphatidylcholine-only bilayers.
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Wenzel TJ, Kwong E, Bajwa E, Klegeris A. Resolution-Associated Molecular Patterns (RAMPs) as Endogenous Regulators of Glia Functions in Neuroinflammatory Disease. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2020; 19:483-494. [DOI: 10.2174/1871527319666200702143719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/17/2020] [Accepted: 04/20/2020] [Indexed: 01/01/2023]
Abstract
Glial cells, including microglia and astrocytes, facilitate the survival and health of all cells
within the Central Nervous System (CNS) by secreting a range of growth factors and contributing to
tissue and synaptic remodeling. Microglia and astrocytes can also secrete cytotoxins in response to
specific stimuli, such as exogenous Pathogen-Associated Molecular Patterns (PAMPs), or endogenous
Damage-Associated Molecular Patterns (DAMPs). Excessive cytotoxic secretions can induce the death
of neurons and contribute to the progression of neurodegenerative disorders, such as Alzheimer’s disease
(AD). The transition between various activation states of glia, which include beneficial and detrimental
modes, is regulated by endogenous molecules that include DAMPs, cytokines, neurotransmitters,
and bioactive lipids, as well as a diverse group of mediators sometimes collectively referred to as
Resolution-Associated Molecular Patterns (RAMPs). RAMPs are released by damaged or dying CNS
cells into the extracellular space where they can induce signals in autocrine and paracrine fashions by
interacting with glial cell receptors. While the complete range of their effects on glia has not been described
yet, it is believed that their overall function is to inhibit adverse CNS inflammatory responses,
facilitate tissue remodeling and cellular debris removal. This article summarizes the available evidence
implicating the following RAMPs in CNS physiological processes and neurodegenerative diseases:
cardiolipin (CL), prothymosin α (ProTα), binding immunoglobulin protein (BiP), heat shock protein
(HSP) 10, HSP 27, and αB-crystallin. Studies on the molecular mechanisms engaged by RAMPs could
identify novel glial targets for development of therapeutic agents that effectively slow down neuroinflammatory
disorders including AD.
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Affiliation(s)
- Tyler J. Wenzel
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Evan Kwong
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Ekta Bajwa
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
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Siu JH, Motallebzadeh R, Pettigrew GJ. Humoral autoimmunity after solid organ transplantation: Germinal ideas may not be natural. Cell Immunol 2020; 354:104131. [DOI: 10.1016/j.cellimm.2020.104131] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/11/2020] [Accepted: 05/11/2020] [Indexed: 12/22/2022]
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Sghaier R, Zarrouk A, Nury T, Badreddine I, O'Brien N, Mackrill JJ, Vejux A, Samadi M, Nasser B, Caccia C, Leoni V, Moreau T, Cherkaoui-Malki M, Salhedine Masmoudi A, Lizard G. Biotin attenuation of oxidative stress, mitochondrial dysfunction, lipid metabolism alteration and 7β-hydroxycholesterol-induced cell death in 158N murine oligodendrocytes. Free Radic Res 2019; 53:535-561. [PMID: 31039616 DOI: 10.1080/10715762.2019.1612891] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Mitochondrial dysfunction and oxidative stress are involved in neurodegenerative diseases associated with an enhancement of lipid peroxidation products such as 7β-hydroxycholesterol (7β-OHC). It is, therefore, important to study the ability of 7β-OHC to trigger mitochondrial defects, oxidative stress, metabolic dysfunctions and cell death, which are hallmarks of neurodegeneration, and to identify cytoprotective molecules. The effects of biotin were evaluated on 158N murine oligodendrocytes, which are myelin synthesizing cells, exposed to 7β-OHC (50 µM) with or without biotin (10 and 100 nM) or α-tocopherol (positive control of cytoprotection). The effects of biotin on 7β-OHC activities were determined using different criteria: cell adhesion; plasma membrane integrity; redox status. The impact on mitochondria was characterized by the measurement of transmembrane mitochondrial potential (ΔΨm), reactive oxygen species (ROS) overproduction, mitochondrial mass, quantification of cardiolipins and organic acids. Sterols and fatty acids were also quantified. Cell death (apoptosis, autophagy) was characterized by the enumeration of apoptotic cells, caspase-3 activation, identification of autophagic vesicles, and activation of LC3-I into LC3-II. Biotin attenuates 7β-OHC-induced cytotoxicity: loss of cell adhesion was reduced; antioxidant activities were normalized. ROS overproduction, protein and lipid oxidation products were decreased. Biotin partially restores mitochondrial functions: attenuation of the loss of ΔΨm; reduced levels of mitochondrial O2•- overproduction; normalization of cardiolipins and organic acid levels. Biotin also normalizes cholesterol and fatty acid synthesis, and prevents apoptosis and autophagy (oxiapoptophagy). Our data support that biotin, which prevents oligodendrocytes damages, could be useful in the treatment of neurodegeneration and demyelination.
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Affiliation(s)
- Randa Sghaier
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France.,Laboratory of Biochemistry, Faculty of Medicine , University Sousse , Sousse , Tunisia.,Faculty of Medicine, Laboratory - NAFS "Nutrition - Functional Food & Vascular Health" , Monastir & University Sousse , Sousse , Tunisia.,Laboratory of Biotechnology and Valorisation of Bio-Géo Ressources , University Manouba, Higher Institute of Biotechnology , Sidi Thabet , Tunisia
| | - Amira Zarrouk
- Laboratory of Biochemistry, Faculty of Medicine , University Sousse , Sousse , Tunisia.,Faculty of Medicine, Laboratory - NAFS "Nutrition - Functional Food & Vascular Health" , Monastir & University Sousse , Sousse , Tunisia.,School of Food and Nutritional Sciences , University College Cork , Cork , Ireland.,Department of Physiology , Biosciences Institute, University College Cork , Cork , Ireland
| | - Thomas Nury
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France
| | - Ilham Badreddine
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France.,University Ibn Zohr, Lab. 'Valorisation des Ressources Naturelles et Environnement' , Taroudant , Morocco.,Laboratory Neuroscience and Biochemistry , University Hassan 1er , Settat , Morocco
| | - Nora O'Brien
- School of Food and Nutritional Sciences , University College Cork , Cork , Ireland
| | - John J Mackrill
- Department of Physiology , Biosciences Institute, University College Cork , Cork , Ireland
| | - Anne Vejux
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France
| | - Mohammad Samadi
- Department of Chemistry , University Lorraine, Metz Technopôle , Metz , France
| | - Boubker Nasser
- Laboratory Neuroscience and Biochemistry , University Hassan 1er , Settat , Morocco
| | - Claudio Caccia
- Laboratory of Medical Genetics and Neurogenetics , Foundation IRCCS Istituto Neurologico Carlo Besta , Milan , Italy
| | - Valerio Leoni
- Laboratory of Clinical Chemistry , Hospital of Varese, ASST-Settelaghi , Milan , Italy
| | - Thibault Moreau
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France.,Department of Neurology , University Hospital , Dijon , France
| | - Mustapha Cherkaoui-Malki
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France
| | - Ahmed Salhedine Masmoudi
- Laboratory of Biotechnology and Valorisation of Bio-Géo Ressources , University Manouba, Higher Institute of Biotechnology , Sidi Thabet , Tunisia
| | - Gérard Lizard
- University Bourgogne Franche-Comté/Inserm , Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' , Dijon , France
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11
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Wirestam L, Arve S, Linge P, Bengtsson AA. Neutrophils-Important Communicators in Systemic Lupus Erythematosus and Antiphospholipid Syndrome. Front Immunol 2019; 10:2734. [PMID: 31824510 PMCID: PMC6882868 DOI: 10.3389/fimmu.2019.02734] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 11/07/2019] [Indexed: 12/15/2022] Open
Abstract
Systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS) are two autoimmune diseases that can occur together or separately. Insights into the pathogenesis have revealed similarities, such as development of autoantibodies targeting subcellular antigens as well as a shared increased risk of cardiovascular morbidity, potentially due to mutual pathologic mechanisms. In this review, we will address the evidence implicating neutrophils in the pathogenesis of these conditions, highlighting their shared features. The neutrophil is the most abundant leukocyte, recognized for its role in infectious and inflammatory diseases, but dysregulation of neutrophil effector functions, including phagocytosis, oxidative burst and formation of neutrophil extracellular traps (NETs) may also contribute to an autoimmune process. The phenotype of neutrophils in SLE and APS differs from neutrophils of healthy individuals, where neutrophils in SLE and APS are activated and prone to aggregate. A specific subset of low-density neutrophils with different function compared to normal-density neutrophils can also be found within the peripheral blood mononuclear cell (PBMC) fraction after density gradient centrifugation of whole blood. Neutrophil phagocytosis is required for regular clearance of cell remnants and nuclear material. Reactive oxygen species (ROS) released by neutrophils during oxidative burst are important for immune suppression and impairment of ROS production is seen in SLE. NETs mediate pathology in both SLE and APS via several mechanisms, including exposure of autoantigens, priming of T-cells and activation of autoreactive B-cells. NETs are also involved in cardiovascular events by forming a pro-thrombotic scaffolding surface. Lastly, neutrophils communicate with other cells by producing cytokines, such as Interferon (IFN) -α, and via direct cell-cell contact. Physiological neutrophil effector functions are necessary to prevent autoimmunity, but in SLE and APS these are altered.
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Affiliation(s)
- Lina Wirestam
- Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Sabine Arve
- Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Petrus Linge
- Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Anders A Bengtsson
- Section of Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
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12
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Suematsu R, Miyamoto T, Saijo S, Yamasaki S, Tada Y, Yoshida H, Miyake Y. Identification of lipophilic ligands of Siglec5 and -14 that modulate innate immune responses. J Biol Chem 2019; 294:16776-16788. [PMID: 31551352 DOI: 10.1074/jbc.ra119.009835] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/02/2019] [Indexed: 01/22/2023] Open
Abstract
Sialic acid-binding immunoglobulin-like lectins (Siglecs) are a family of cell-surface immune receptors that bind to sialic acid at terminal glycan residues. Siglecs also recognize nonsialic acid ligands, many of which remain to be characterized. Here, we found that Siglec5 and Siglec14 recognize lipid compounds produced by Trichophyton, a fungal genus containing several pathogenic species. Biochemical approaches revealed that the Siglec ligands are fungal alkanes and triacylglycerols, an unexpected finding that prompted us to search for endogenous lipid ligands of Siglecs. Siglec5 weakly recognized several endogenous lipids, but the mitochondrial lipid cardiolipin and the anti-inflammatory lipid 5-palmitic acid-hydroxystearic acid exhibited potent ligand activity on Siglec5. Further, the hydrophobic stretch in the Siglec5 N terminus region was found to be required for efficient recognition of these lipids. Notably, this hydrophobic stretch was dispensable for recognition of sialic acid. Siglec5 inhibited cell activation upon ligand binding, and accordingly, the lipophilic ligands suppressed interleukin-8 (IL-8) production in Siglec5-expressing human monocytic cells. Siglec14 and Siglec5 have high sequence identity in the extracellular region, and Siglec14 also recognized the endogenous lipids. However, unlike Siglec5, Siglec14 transduces activating signals upon ligand recognition. Indeed, the endogenous lipids induced IL-8 production in Siglec14-expressing human monocytic cells. These results indicated that Siglec5 and Siglec14 can recognize lipophilic ligands that thereby modulate innate immune responses. To our knowledge, this is the first study reporting the binding of Siglecs to lipid ligands, expanding our understanding of the biological function and importance of Siglecs in the innate immunity.
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Affiliation(s)
- Rie Suematsu
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga 849-8501, Japan.,Department of Rheumatology, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Tomofumi Miyamoto
- Department of Natural Products Chemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Shinobu Saijo
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba 260-8673, Japan
| | - Sho Yamasaki
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba 260-8673, Japan.,Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Suita 565-0871, Japan.,Laboratory of Molecular Immunology, Immunology Frontier Research Center, Osaka University, Suita, 565-0871, Japan
| | - Yoshifumi Tada
- Department of Rheumatology, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Yasunobu Miyake
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga 849-8501, Japan
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13
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Ren M, Xu Y, Erdjument-Bromage H, Donelian A, Phoon CKL, Terada N, Strathdee D, Neubert TA, Schlame M. Extramitochondrial cardiolipin suggests a novel function of mitochondria in spermatogenesis. J Cell Biol 2019; 218:1491-1502. [PMID: 30914420 PMCID: PMC6504895 DOI: 10.1083/jcb.201808131] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/29/2018] [Accepted: 03/07/2019] [Indexed: 12/03/2022] Open
Abstract
The acrosome is a protease-rich organelle in sperm essential for fertilization but little is known about acrosome biogenesis. Ren et al. find that the mitochondrial lipid cardiolipin and some mitochondrial proteins translocate to the acrosome during spermatogenesis, suggesting that mitochondria directly contribute to the assembly of this sperm-specific organelle. Mitochondria contain cardiolipin (CL), an organelle-specific phospholipid that carries four fatty acids with a strong preference for unsaturated chains. Unsaturation is essential for the stability and for the function of mitochondrial CL. Surprisingly, we found tetrapalmitoyl-CL (TPCL), a fully saturated species, in the testes of humans and mice. TPCL was absent from other mouse tissues but was the most abundant CL species in testicular germ cells. Most intriguingly, TPCL was not localized in mitochondria but was in other cellular membranes even though mitochondrial CL was the substrate from which TPCL was synthesized. During spermiogenesis, TPCL became associated with the acrosome, a sperm-specific organelle, along with a subset of authentic mitochondrial proteins, including Ant4, Suox, and Spata18. Our data suggest that mitochondria-derived membranes are assembled into the acrosome, challenging the concept that this organelle is strictly derived from the Golgi apparatus and revealing a novel function of mitochondria.
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Affiliation(s)
- Mindong Ren
- Department of Anesthesiology, New York University School of Medicine, New York, NY .,Department of Cell Biology, New York University School of Medicine, New York, NY
| | - Yang Xu
- Department of Anesthesiology, New York University School of Medicine, New York, NY
| | - Hediye Erdjument-Bromage
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY.,Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY
| | - Alec Donelian
- Department of Anesthesiology, New York University School of Medicine, New York, NY
| | - Colin K L Phoon
- Department of Pediatrics, New York University School of Medicine, New York, NY
| | - Naohiro Terada
- Department of Pathology, University of Florida College of Medicine, Gainesville, FL
| | - Douglas Strathdee
- Transgenic Technology Laboratory, Cancer Research UK Beatson Institute, Glasgow, UK
| | - Thomas A Neubert
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY.,Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY
| | - Michael Schlame
- Department of Anesthesiology, New York University School of Medicine, New York, NY .,Department of Cell Biology, New York University School of Medicine, New York, NY
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14
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Spencer DA, Quiniou SMA, Crider J, Musungu B, Bengten E, Wilson M. Insights into the dynamics of memory, effector and apoptotic cytotoxic T lymphocytes in channel catfish, Ictalurus punctatus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2019; 92:116-128. [PMID: 30447233 DOI: 10.1016/j.dci.2018.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/03/2018] [Accepted: 11/03/2018] [Indexed: 06/09/2023]
Abstract
In this study, we used the channel catfish model clonal TS32.15 alloantigen-specific cytotoxic T cell (CTL) line to examine the dynamics of memory CTL expansion and senescence in teleosts. Although TS32.15 has been routinely cultured to study catfish CTL responses and killing mechanisms, little is known about the dynamics of the CTLs in these cultures. Here we show that this cell line consists of small non-cytotoxic T cells and larger granular effector T cells and that their ratios vary with time after stimulation. Small CTLs, when exposed to their irradiated targets, replicate and differentiate to morphologically distinct cytotoxic effectors, which do not replicate. After lysing target cells, or with prolonged absence of stimulation, the effector cells transition to a non-cytolytic senescent stage or become apoptotic. In addition, we demonstrate that natural IgM in catfish serum binds lipids, including PIP2, on early apoptotic CTLs, and that these IgM+ CTL can be cleared by catfish head kidney-derived macrophages.
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Affiliation(s)
- David A Spencer
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, 39216, USA
| | - Sylvie M A Quiniou
- Warmwater Aquaculture Research Unit, U.S. Department of Agriculture-Agricultural Research Service, Stoneville, MS, 38776, USA
| | - Jonathan Crider
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, 39216, USA
| | - Bryan Musungu
- Warmwater Aquaculture Research Unit, U.S. Department of Agriculture-Agricultural Research Service, Stoneville, MS, 38776, USA
| | - Eva Bengten
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, 39216, USA
| | - Melanie Wilson
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, 39216, USA
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15
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Pointer CB, Wenzel TJ, Klegeris A. Extracellular cardiolipin regulates select immune functions of microglia and microglia-like cells. Brain Res Bull 2019; 146:153-163. [PMID: 30625370 DOI: 10.1016/j.brainresbull.2019.01.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/20/2018] [Accepted: 01/03/2019] [Indexed: 12/12/2022]
Abstract
Cardiolipin is a mitochondrial membrane phospholipid with several well-defined metabolic roles. Cardiolipin can be released extracellularly by damaged cells and has been shown to affect peripheral immune functions. We hypothesized that extracellular cardiolipin can also regulate functions of microglia, the resident immune cells of the central nervous system (CNS). We demonstrate that extracellular cardiolipin increases microglial phagocytosis and neurotrophic factor expression, as well as decreases the release of inflammatory mediators and cytotoxins by activated microglia-like cells. These results identify extracellular cardiolipin as a potential CNS intercellular signaling molecule that can regulate key microglial immune functions associated with neurodegenerative diseases.
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Affiliation(s)
- Caitlin B Pointer
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Tyler J Wenzel
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia, V1V 1V7, Canada.
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16
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Bajwa E, Pointer CB, Klegeris A. The Role of Mitochondrial Damage-Associated Molecular Patterns in Chronic Neuroinflammation. Mediators Inflamm 2019; 2019:4050796. [PMID: 31065234 PMCID: PMC6466851 DOI: 10.1155/2019/4050796] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 03/01/2019] [Accepted: 03/06/2019] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial dysfunction has been established as a common feature of neurodegenerative disorders that contributes to disease pathology by causing impaired cellular energy production. Mitochondrial molecules released into the extracellular space following neuronal damage or death may also play a role in these diseases by acting as signaling molecules called damage-associated molecular patterns (DAMPs). Mitochondrial DAMPs have been shown to initiate proinflammatory immune responses from nonneuronal glial cells, including microglia and astrocytes; thereby, they have the potential to contribute to the chronic neuroinflammation present in these disorders accelerating the degeneration of neurons. In this review, we highlight the mitochondrial DAMPs cytochrome c (CytC), mitochondrial transcription factor A (TFAM), and cardiolipin and explore their potential role in the central nervous system disorders including Alzheimer's disease and Parkinson's disease, which are characterized by neurodegeneration and chronic neuroinflammation.
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Affiliation(s)
- Ekta Bajwa
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC, Canada
| | - Caitlin B. Pointer
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC, Canada
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17
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Grazioli S, Pugin J. Mitochondrial Damage-Associated Molecular Patterns: From Inflammatory Signaling to Human Diseases. Front Immunol 2018; 9:832. [PMID: 29780380 PMCID: PMC5946030 DOI: 10.3389/fimmu.2018.00832] [Citation(s) in RCA: 241] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/05/2018] [Indexed: 12/20/2022] Open
Abstract
Over the recent years, much has been unraveled about the pro-inflammatory properties of various mitochondrial molecules once they are leaving the mitochondrial compartment. On entering the cytoplasm or the extracellular space, mitochondrial DAMPs (also known as mitochondrial alarmins) can become pro-inflammatory and initiate innate and adaptive immune responses by activating cell surface and intracellular receptors. Current evidence indicates that uncontrolled and excessive release of mitochondrial DAMPs is associated with severity, has prognosis value in human diseases, and contributes to the dysregulated process observed in numerous inflammatory and autoimmune conditions, as well as in ischemic heart disease and cancer. Herein, we review that the expanding research field of mitochondrial DAMPs in innate immune responses and the current knowledge on the association between mitochondrial DAMPs and human diseases.
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Affiliation(s)
- Serge Grazioli
- Pediatric Intensive Care Unit, Department of Pediatrics, University Hospital of Geneva, University of Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Jérôme Pugin
- Intensive Care Unit, Department of Anesthesiology, Faculty of Medicine, University Hospital of Geneva, University of Geneva, Geneva, Switzerland
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18
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Abstract
Systemic lupus erythematosus (lupus, SLE) is a chronic autoimmune disease characterized by the production of autoantibodies, which bind to antigens and are deposited within tissues to fix complement, resulting in widespread systemic inflammation. The studies presented herein are consistent with hyperpolarized, adenosine triphosphate (ATP)-deficient mitochondria being central to the disease process. These hyperpolarized mitochondria resist the depolarization required for activation-induced apoptosis. The mitochondrial ATP deficits add to this resistance to apoptosis and also reduce the macrophage energy that is needed to clear apoptotic bodies. In both cases, necrosis, the alternative pathway of cell death, results. Intracellular constituents spill into the blood and tissues, eliciting inflammatory responses directed at their removal. What results is “autoimmunity.” Ultraviolet (UV)-A1 photons have the capacity to remediate this aberrancy. Exogenous exposure to low-dose, full-body, UV-A1 radiation generates singlet oxygen. Singlet oxygen has two major palliative actions in patients with lupus and the UV-A1 photons themselves have several more. Singlet oxygen depolarizes the hyperpolarized mitochondrion, triggering non-ATP-dependent apoptosis that deters necrosis. Next, singlet oxygen activates the gene encoding heme oxygenase (HO-1), a major governor of systemic homeostasis. HO-1 catalyzes the degradation of the oxidant heme into biliverdin (converted to bilirubin), Fe, and carbon monoxide (CO), the first three of these exerting powerful antioxidant effects, and in conjunction with a fourth, CO, protecting against injury to the coronary arteries, the central nervous system, and the lungs. The UV-A1 photons themselves directly attenuate disease in lupus by reducing B cell activity, preventing the suppression of cell-mediated immunity, slowing an epigenetic progression toward SLE, and ameliorating discoid and subacute cutaneous lupus. Finally, a combination of these mechanisms reduces levels of anticardiolipin antibodies and protects during lupus pregnancy. Capping all of this is that UV-A1 irradiation is an essentially innocuous, highly manageable, and comfortable therapeutic agency.
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Affiliation(s)
- H McGrath
- Veterans Administration, New Orleans, LA, USA
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19
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Boura P, Tselios K, Skendros P, Kountouras J. Antiphospholipid Syndrome in Greece: Clinical and Immunological Study and Review of the Literature. Angiology 2016; 55:421-30. [PMID: 15258688 DOI: 10.1177/000331970405500409] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aim of this paper is to analyze the epidemiologic, clinical, and immunologic characteristics of the antiphospholipid syndrome (APS), primary or secondary, in autoimmune patients from Northern Greece. Sixty-seven patients with APS were included (9 men, 13.4%, and 58 women, 86.6%). Fifty-two (77.6%) patients had secondary APS and 15 had primary APS (22.4%). The mean age was 46.0 ±15.4 years and the mean follow-up period was 62.7 ±15.0 months. Medical records were retrospectively analyzed from January 1994 until December 2001, according to a preestablished protocol. Eight patients (11.9%) had arterial thrombosis, 12 (17.9%) had vein thrombosis, 12 (17.9%) had thrombocytopenia, 20 (29.8%) had neurologic disorders, and 51.6% of the women in reproductive age had, at least 2 fetal losses (higher frequency in primary APS). Thirty-six patients (53.7%) had increased levels of both immunoglobulin G (IgG) and IgM anticardiolipin antibodies (ACA), 19 (28.4%) had IgG ACA only, and 12 (17.7%) had IgM ACA only. Antinuclear antibodies (ANA) were detected in 46 (68.6%) patients, and antineutrophil cytoplasmic antibodies (ANCA) in 29 (43.3%). All patients were prophylactically treated with aspirin (50-100 mg/day) and low-molecular-weight heparin and/or intravenous immunoglobulins-IVIGs occasionally (pregnant women). The findings of this study are, generally, similar to those described by others. Miscarriages seem to be more frequent in women with primary APS (p<0.05), compared to other studies. Differences between these findings and those described by others concerning epidemiologic, clinical, or immunologic data are discussed.
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Affiliation(s)
- Panagiota Boura
- Outpatient Clinic, 2nd Department of Internal Medicine, Aristotle University of Thessaloniki, Hippokration Hospital, Greece.
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20
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Regulation of autophagy by mitochondrial phospholipids in health and diseases. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:114-129. [PMID: 27502688 DOI: 10.1016/j.bbalip.2016.08.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/28/2016] [Accepted: 08/04/2016] [Indexed: 12/16/2022]
Abstract
Autophagy is an evolutionarily conserved mechanism that maintains nutrient homeostasis by degrading protein aggregates and damaged organelles. Autophagy is reduced in aging, which is implicated in the pathogenesis of aging-related diseases, including cancers, obesity, type 2 diabetes, cardiovascular diseases, and neurodegenerative diseases. Mitochondria-derived phospholipids cardiolipin, phosphatidylethanolamine, and phosphatidylglycerol are critical throughout the autophagic process, from initiation and phagophore formation to elongation and fusion with endolysosomal vesicles. Cardiolipin is also required for mitochondrial fusion and fission, an important step in isolating dysfunctional mitochondria for mitophagy. Furthermore, genetic screen in yeast has identified a surprising role for cardiolipin in regulating lysosomal function. Phosphatidylethanolamine plays a pivotal role in supporting the autophagic process, including autophagosome elongation as part of lipidated Atg8/LC3. An emerging role for phosphatidylglycerol in AMPK and mTORC1 signaling as well as mitochondrial fission may provide the first glimpse into the function of phosphatidylglycerol apart from being a precursor for cardiolipin. This review examines the effects of manipulating phospholipids on autophagy and mitophagy in health and diseases, as well as current limitations in the field. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum.
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21
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Andrejevic S, Bonaci-Nikolic B, Sefik-Bukilica M, Petrovic R. Clinical and serological follow-up of 71 patients with anti-mitochondrial type 5 antibodies. Lupus 2016; 16:788-93. [PMID: 17895301 DOI: 10.1177/0961203307081913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Antimitochondrial M5 type antibodies (AMA M5) have been described in patients with antiphospholipid syndrome (APS), thrombocytopenia and autoimmune hemolytic anemia. The aim of this study was to describe the clinical and immunological characteristics of a series of patients with AMA M5. We analyzed 71 patients with AMA M5 seen consecutively at our centres during the last 8 years. The clinical and immunological characteristics of diseases expression were compared with 70 consecutive disease control patients without AMA M5. Compared with the control group, AMA M5 positive patients presented higher prevalence of false positive VDRL test ( P < 0.001) and thrombocytopenia ( P = 0.002) with lower levels of anti-β2 glycoprotein I antibodies. In AMA M5 patients (56 female, 15 male) a heterogeneous group of disorders were found. Twenty-seven (38%) patients fulfilled the Sapporo criteria for the classification of the APS. Laboratory criteria were met in 55 (77.5%), and clinical criteria in 31 (43.7%) patients. Six patients initially presented with non-criteria features of APS during follow-up period developed APS. Younger patients with AMA M5 should be carefully observed for the development of APS, even in the absence of serological criteria, while elderly must be screened for monoclonal gammopathy and hematological disorders. Lupus (2007) 16, 788—793.
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Affiliation(s)
- S Andrejevic
- Institute of Allergy and Clinical Immunology, Clinical Center of Serbia, Koste Todorovica 2, Belgrade 11000, Serbia.
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22
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McGrath H. Elimination of anticardiolipin antibodies and cessation of cognitive decline in a UV-A1-irradiated systemic lupus erythematosus patient. Lupus 2016; 14:859-61. [PMID: 16304728 DOI: 10.1191/0961203305lu2164cr] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In the first patient with high levels of anticardiolipin antibodies (aCL) treated with ultraviolet-A1 (UV-A1; 320-400 nm) radiation, eight months of twice-weekly low-dose (10 J/cm2) irradiation was accompanied by the decrease of aCL levels to normal, cessation of clinical and positron emission tomographic (PET) scanning evidence of cognitive decline, and reversal of livedo reticularis. All occurred within the framework of an improving Revised Systemic Lupus Activity Measure (SLAM-R) score. Further studies in systemic lupus erythematosus (SLE) patients with elevated aCL are indicated.
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Affiliation(s)
- H McGrath
- Department of Medicine/Rheumatology, Louisiana State University Medical Center, New Orleans, LA 70112, USA.
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23
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Weiss SC, Egetenmeyer N, Schulz W. Coupling of In Vitro Bioassays with Planar Chromatography in Effect-Directed Analysis. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 157:187-224. [PMID: 27757476 DOI: 10.1007/10_2016_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Modern analytical test methods increasingly detect anthropogenic organic substances and their transformation products in water samples and in the environment. The presence of these compounds might pose a risk to the aquatic environment. To determine a possible (eco)toxicological risk, aquatic samples are tested using various bioassays, including sub-organismic assays such as the luminescent bacteria inhibition test, the acetylcholinesterase inhibition test, and the umu-test. The effect-directed analysis (EDA) combines physicochemical separation methods with biological (in vitro) tests. High-performance thin-layer chromatography (HPTLC) has proved to be particularly well suited for the separation of organic compounds and the subsequent analysis of effects by the application of the biotests directly on the surface of the HPTLC plate. The advantage of using HPTLC in comparison to high-performance liquid chromatography (HPLC) for EDA is that the solvent which is used as a mobile phase during chromatography is completely evaporated after the separation and therefore can no longer influence the applied bioassays.A prioritization during the complex identification process can be achieved when observed effects are associated with the separated zones in HPTLC. This increases the probability of identifying the substance responsible for an adverse effect from the multitude of organic trace substances in environmental samples. Furthermore, by comparing the pattern of biological effects of a separated sample, it is possible to track and assess changes in biological activity over time, over space, or in the course of a process, even without identifying the substance. HPTLC has already been coupled with various bioassays.Because HPTLC is a very flexible system, various detection techniques can be used and combined. In addition to the UV/Vis absorption and fluorescence measurements, TLC can also be coupled with a mass spectrometer (MS) for compound identification. In addition, detection of functional groups by means of derivatization reagents can support this identification. It is also possible to combine derivatization and HPLC-MS.Two case studies are used to illustrate the significance of HPTLC-EDA in investigating water quality: Study on a wastewater treatment plant Possible influence of an artificial turf surface on ground water.
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Affiliation(s)
- Stefan C Weiss
- Betriebs und Forschungslaboratorium, Zweckverband Landeswasserversorgung (LW), Am Spitzigen Berg 1, 89129, Langenau, Germany.
| | - Nicole Egetenmeyer
- Betriebs und Forschungslaboratorium, Zweckverband Landeswasserversorgung (LW), Am Spitzigen Berg 1, 89129, Langenau, Germany
| | - Wolfgang Schulz
- Betriebs und Forschungslaboratorium, Zweckverband Landeswasserversorgung (LW), Am Spitzigen Berg 1, 89129, Langenau, Germany
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24
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Nakahira K, Hisata S, Choi AMK. The Roles of Mitochondrial Damage-Associated Molecular Patterns in Diseases. Antioxid Redox Signal 2015; 23:1329-50. [PMID: 26067258 PMCID: PMC4685486 DOI: 10.1089/ars.2015.6407] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SIGNIFICANCE Mitochondria, vital cellular power plants to generate energy, are involved in immune responses. Mitochondrial damage-associated molecular patterns (DAMPs) are molecules that are released from mitochondria to extracellular space during cell death and include not only proteins but also DNA or lipids. Mitochondrial DAMPs induce inflammatory responses and are critically involved in the pathogenesis of various diseases. RECENT ADVANCES Recent studies elucidate the molecular mechanisms by which mitochondrial DAMPs are released and initiate immune responses by use of genetically modulated cells or animals. Importantly, the levels of mitochondrial DAMPs in patients are often associated with severity and prognosis of human diseases, such as infection, asthma, ischemic heart disease, and cancer. CRITICAL ISSUES Although mitochondrial DAMPs can represent proinflammatory molecules in various experimental models, their roles in human diseases may be multifunctional and complex. It remains unclear where and how mitochondrial DAMPs are liberated into extracellular spaces and exert their biological functions particularly in vivo. In addition, while mitochondria can secrete several types of DAMPs during cell death, the interaction of each mitochondrial DAMP (e.g., synergistic effects) remains unclear. FUTURE DIRECTIONS Regulation of mitochondrial DAMP-mediated immune responses may be important to alter the progression of human diseases. In addition, measuring mitochondrial DAMPs in patients may be clinically useful as biomarkers to predict prognosis or response to therapies. Further studies of the mechanisms by which mitochondrial DAMPs impact the initiation and progression of diseases may lead to the development of therapeutics specifically targeting this pathway. Antioxid.
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Affiliation(s)
- Kiichi Nakahira
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
| | - Shu Hisata
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
| | - Augustine M K Choi
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
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25
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Altered Traffic of Cardiolipin during Apoptosis: Exposure on the Cell Surface as a Trigger for "Antiphospholipid Antibodies". J Immunol Res 2015; 2015:847985. [PMID: 26491702 PMCID: PMC4603604 DOI: 10.1155/2015/847985] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/06/2015] [Indexed: 02/07/2023] Open
Abstract
Apoptosis has been reported to induce changes in the remodelling of membrane lipids; after death receptor engagement, specific changes of lipid composition occur not only at the plasma membrane, but also in intracellular membranes. This paper focuses on one important aspect of apoptotic changes in cellular lipids, namely, the redistribution of the mitochondria-specific phospholipid, cardiolipin (CL). CL predominantly resides in the inner mitochondrial membrane, even if the rapid remodelling of its acyl chains and the subsequent degradation occur in other membrane organelles. After death receptor stimulation, CL appears to concentrate into mitochondrial “raft-like” microdomains at contact sites between inner and outer mitochondrial membranes, leading to local oligomerization of proapoptotic proteins, including Bid. Clustering of Bid in CL-enriched contacts sites is interconnected with pathways of CL remodelling that intersect membrane traffic routes dependent upon actin. In addition, CL association with cytoskeleton protein vimentin was observed. Such novel association also indicated that CL molecules may be expressed at the cell surface following apoptotic stimuli. This observation adds a novel implication of biomedical relevance. The association of CL with vimentin at the cell surface may represent a “new” target antigen in the context of the apoptotic origin of anti-vimentin/CL autoantibodies in Antiphospholipid Syndrome.
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Vergara D, D'Alessandro M, Rizzello A, De Riccardis L, Lunetti P, Del Boccio P, De Robertis F, Trianni G, Maffia M, Giudetti AM. A lipidomic approach to the study of human CD4(+) T lymphocytes in multiple sclerosis. BMC Neurosci 2015. [PMID: 26205308 PMCID: PMC4513631 DOI: 10.1186/s12868-015-0183-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Background Lipids play different important roles in central nervous system so that dysregulation of lipid pathways has been implicated in a growing
number of neurodegenerative disorders including multiple sclerosis (MS). MS is the most prevalent autoimmune disorder of the central nervous system, with neurological symptoms caused by inflammation and demyelination. In this study, a lipidomic analysis was performed for the rapid profile of CD4+ T lymphocytes from MS patient and control samples in an untargeted approach. Methods A matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry based approach was used for the analysis of lipid extracts using 9-aminoacridine as matrix. Lipids were analyzed in negative mode and selected species fragmented using MALDI tandem mass spectrometry for their structural assignments. Results The analysis reveals some modifications in the phospholipid pattern of MS CD4+ T lymphocytes with respect to healthy controls with a significant increase of cardiolipin species in MS samples. Conclusions These results demonstrate the feasibility of a MALDI-TOF approach for the analysis of CD4+ lipid extracts and suggest how alterations in the lipid metabolism characterized lymphocytes of MS patients.
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Affiliation(s)
- Daniele Vergara
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy. .,Laboratory of Clinical Proteomic, "Giovanni Paolo II" Hospital, ASL-Lecce, Piazzetta F. Muratore, Lecce, Italy.
| | - Michele D'Alessandro
- Department of Medical, Oral and Biotechnological Sciences, Research Centre on Aging (Ce.S.I), "G. d'Annunzio" University Foundation, Chieti-Pescara, Italy.
| | - Antonia Rizzello
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy. .,Laboratory of Clinical Proteomic, "Giovanni Paolo II" Hospital, ASL-Lecce, Piazzetta F. Muratore, Lecce, Italy.
| | - Lidia De Riccardis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy.
| | - Paola Lunetti
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy.
| | - Piero Del Boccio
- Department of Medical, Oral and Biotechnological Sciences, Research Centre on Aging (Ce.S.I), "G. d'Annunzio" University Foundation, Chieti-Pescara, Italy.
| | - Francesca De Robertis
- Department of Neurology, "Vito Fazzi" Hospital, ASL-Lecce, Piazzetta F. Muratore, Lecce, Italy.
| | - Giorgio Trianni
- Department of Neurology, "Vito Fazzi" Hospital, ASL-Lecce, Piazzetta F. Muratore, Lecce, Italy.
| | - Michele Maffia
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy. .,Laboratory of Clinical Proteomic, "Giovanni Paolo II" Hospital, ASL-Lecce, Piazzetta F. Muratore, Lecce, Italy.
| | - Anna M Giudetti
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Monteroni, Lecce, Italy.
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Pericleous C, Ripoll VM, Giles I, Ioannou Y. Laboratory tests for the antiphospholipid syndrome. Methods Mol Biol 2014; 1134:221-35. [PMID: 24497366 DOI: 10.1007/978-1-4939-0326-9_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by recurrent vascular thrombosis (VT) and/or pregnancy morbidity (PM) in the presence of persistent antiphospholipid antibodies (aPL), detected by lupus anticoagulant (LA), anticardiolipin (aCL) antibody, and/or anti-β₂ glycoprotein I (aβ₂GPI) antibody assays. These aPL, considered to be diagnostic markers and pathogenic drivers of APS, are a heterogeneous group of antibodies directed against anionic phospholipids, phospholipid-binding plasma proteins, and phospholipid-protein complexes. Although APS is currently considered as a single disease, it presents with a wide range of clinical symptoms and biological characteristics. The clinical diagnosis of APS in a patient with symptoms and signs is dependent upon the presence of a persistently positive result in an aPL assay. The tests recommended for detecting aPL are the standardized enzyme-linked immunosorbent assay (ELISA) to detect aCL and aβ₂GPI and clotting assays for LA performed according to the guidelines of the International Society on Thrombosis and Haemostasis. This chapter describes the standard laboratory test for the diagnosis of APS discussing the clinical and theoretical aspects of LA, aCL, and aβ₂GPI assays.
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Ren M, Phoon CKL, Schlame M. Metabolism and function of mitochondrial cardiolipin. Prog Lipid Res 2014; 55:1-16. [PMID: 24769127 DOI: 10.1016/j.plipres.2014.04.001] [Citation(s) in RCA: 226] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/04/2014] [Accepted: 04/14/2014] [Indexed: 12/22/2022]
Abstract
Since it has been recognized that mitochondria are crucial not only for energy metabolism but also for other cellular functions, there has been a growing interest in cardiolipin, the specific phospholipid of mitochondrial membranes. Indeed, cardiolipin is a universal component of mitochondria in all eukaryotes. It has a unique dimeric structure comprised of two phosphatidic acid residues linked by a glycerol bridge, which gives rise to unique physicochemical properties. Cardiolipin plays an important role in the structural organization and the function of mitochondrial membranes. In this article, we review the literature on cardiolipin biology, focusing on the most important discoveries of the past decade. Specifically, we describe the formation, the migration, and the degradation of cardiolipin and we discuss how cardiolipin affects mitochondrial function. We also give an overview of the various phenotypes of cardiolipin deficiency in different organisms.
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Affiliation(s)
- Mindong Ren
- Department of Anesthesiology, New York University School of Medicine, New York, USA; Department of Cell Biology, New York University School of Medicine, New York, USA
| | - Colin K L Phoon
- Department of Pediatrics, New York University School of Medicine, New York, USA
| | - Michael Schlame
- Department of Anesthesiology, New York University School of Medicine, New York, USA; Department of Cell Biology, New York University School of Medicine, New York, USA.
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Morlock GE. Chromatography Combined with Bioassays and Other Hyphenations – The Direct Link to the Compound Indicating the Effect. ACS SYMPOSIUM SERIES 2014. [DOI: 10.1021/bk-2014-1185.ch005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Gertrud E. Morlock
- Justus Liebig University Giessen, Interdisciplinary Research Center (IFZ), Institute of Nutritional Science, Chair of Food Science, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
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Leung CWT, Hong Y, Hanske J, Zhao E, Chen S, Pletneva EV, Tang BZ. Superior fluorescent probe for detection of cardiolipin. Anal Chem 2013; 86:1263-8. [PMID: 24372165 DOI: 10.1021/ac403616c] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Cardiolipin (CL) is a unique phospholipid found in mitochondrial inner membrane. It is a key component for mitochondrial function in both respiration and apoptosis. The level of CL is an important parameter for investigating these intracellular events and is a critical indicator of a number of diseases associated with mitochondrial respiratory functions. 10-Nonyl acridine orange (NAO) is the only fluorescent dye currently available for CL detection. However, the performance of NAO is far from satisfactory in terms of selectivity and sensitivity. In this work, we report an aggregation-induced emission-active fluorogen, TTAPE-Me, for CL detection and quantification. With improved sensitivity and excellent selectivity to CL over other major mitochondrial membrane lipids, TTAPE-Me could serve as a valuable fluorescent sensor for CL quantification. The use of TTAPE-Me for the quantification of isolated mitochondria is also demonstrated.
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Affiliation(s)
- Chris W T Leung
- Department of Chemistry, Institute for Advanced Study, Division of Biomedical Engineering, Division of Life Science, State Key Laboratory of Molecular Neuroscience and Institute of Molecular Functional Materials, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong, China
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Emerging roles of lipids in BCL-2 family-regulated apoptosis. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1542-54. [DOI: 10.1016/j.bbalip.2013.03.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 02/28/2013] [Accepted: 03/02/2013] [Indexed: 01/06/2023]
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Leffler J, Gullstrand B, Jönsen A, Nilsson JÅ, Martin M, Blom AM, Bengtsson AA. Degradation of neutrophil extracellular traps co-varies with disease activity in patients with systemic lupus erythematosus. Arthritis Res Ther 2013; 15:R84. [PMID: 23945056 PMCID: PMC3978901 DOI: 10.1186/ar4264] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 08/14/2013] [Indexed: 12/20/2022] Open
Abstract
Introduction The ability to degrade neutrophil extracellular traps (NETs) is reduced in a subset of patients with systemic lupus erythematosus (SLE). NETs consist of chromatin covered with antimicrobial enzymes and are normally degraded by DNase-I, an enzyme which is known to have reduced activity in SLE. Decreased ability to degrade NETs is associated with disease activity. In the current study we investigated how the ability of serum from SLE patients to degrade NETs varies during the course of SLE as well as what impact this may have for the clinical phenotype of SLE. Methods Serum from 69 patients with SLE, included in a prospective study, was taken every 60 days for a median of 784 days. The ability of serum to degrade NETs was determined and associated with clinical parameters occurring before and at the time of sampling, as well as after sampling by using conditional logistic regression. Results As many as 41% of all patients in the study showed decreased ability to degrade NETs at least once, but with a median of 20% of all time points. Decreased degradation was associated with manifestations of glomerulonephritis as well as low complement levels and elevated levels of antibodies directed against histones and DNA. Furthermore, the odds ratio for the patient to develop alopecia and fever after an episode of decreased NETs degradation was increased by four to five times compared to normal. Conclusions Decreased degradation of NETs is associated with clinical manifestations in SLE and may contribute to disease pathogenesis. Potential therapeutics restoring the ability to degrade NETs could be beneficial for certain patients with SLE.
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Koh YT, Scatizzi JC, Gahan JD, Lawson BR, Baccala R, Pollard KM, Beutler BA, Theofilopoulos AN, Kono DH. Role of nucleic acid-sensing TLRs in diverse autoantibody specificities and anti-nuclear antibody-producing B cells. THE JOURNAL OF IMMUNOLOGY 2013; 190:4982-90. [PMID: 23589617 DOI: 10.4049/jimmunol.1202986] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Nucleic acid (NA)-sensing TLRs (NA-TLRs) promote the induction of anti-nuclear Abs in systemic lupus erythematosus. However, the extent to which other nonnuclear pathogenic autoantibody specificities that occur in lupus and independently in other autoimmune diseases depend on NA-TLRs, and which immune cells require NA-TLRs in systemic autoimmunity, remains to be determined. Using Unc93b1(3d) lupus-prone mice that lack NA-TLR signaling, we found that all pathogenic nonnuclear autoantibody specificities examined, even anti-RBC, required NA-TLRs. Furthermore, we document that NA-TLRs in B cells were required for the development of antichromatin and rheumatoid factor. These findings support a unifying NA-TLR-mediated mechanism of autoantibody production that has both pathophysiological and therapeutic implications for systemic lupus erythematosus and several other humoral-mediated autoimmune diseases. In particular, our findings suggest that targeting of NA-TLR signaling in B cells alone would be sufficient to specifically block production of a broad diversity of autoantibodies.
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Affiliation(s)
- Yi Ting Koh
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
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Nayfe R, Uthman I, Aoun J, Saad Aldin E, Merashli M, Khamashta MA. Seronegative antiphospholipid syndrome. Rheumatology (Oxford) 2013; 52:1358-67. [PMID: 23502076 DOI: 10.1093/rheumatology/ket126] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
APS is an autoimmune disease that leads to arterial and/or venous thrombosis, recurrent pregnancy loss and persistently positive aPLs. Patients with clinical manifestations highly suggestive of APS but persistently negative conventional aPLs are classified as having seronegative APS. Ongoing research has revealed the existence of non-criteria antibodies proposed to be relevant to APS and that can be potentially included in the disease's classification criteria. We present a literature review on the most promising antibodies of this heterogeneous aPL family, which includes antibodies to a zwitterionic phospholipid, namely phosphatidylethanolamine, phospholipid-binding plasma proteins, phospholipid-protein complexes and anionic phospholipids other than cardiolipin. Although these molecules can increase the diagnostic yield of APS, their clinical relevance is still debatable and needs to be confirmed by interlaboratory efforts toward standardizing diagnostic tools, in addition to experimental data and larger longitudinal studies.
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Affiliation(s)
- Rabih Nayfe
- Department of Internal Medicine, American University of Beirut Medical Center, PO Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon
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Jovanović V, Abdul Aziz N, Lim YT, Ng Ai Poh A, Jin Hui Chan S, Ho Xin Pei E, Lew FC, Shui G, Jenner AM, Bowen L, McKinney EF, Lyons PA, Kemeny MD, Smith KGC, Wenk MR, MacAry PA. Lipid anti-lipid antibody responses correlate with disease activity in systemic lupus erythematosus. PLoS One 2013; 8:e55639. [PMID: 23409013 PMCID: PMC3567138 DOI: 10.1371/journal.pone.0055639] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 12/28/2012] [Indexed: 12/17/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by broad clinical manifestations including cardiovascular and renal complications with periodic disease flares and significant morbidity and mortality. One of the main contributing factors to the pathology of SLE is the accumulation and impaired clearance of immune complexes of which the principle components are host auto-antigens and antibodies. The contribution of host lipids to the formation of these autoimmune complexes remains poorly defined. The aim of the present study was to identify and analyze candidate lipid autoantigens and their corresponding anti-lipid antibody responses in a well-defined SLE patient cohort using a combination of immunological and biophysical techniques. Disease monitoring in the SLE cohort was undertaken with serial British Isles Lupus Assessment Group (BILAG) scoring. Correlations between specific lipid/anti-lipid responses were investigated as disease activity developed from active flares to quiescent during a follow up period. We report a significant negative correlation between anti-lipid antibodies for 24S-hydroxycholesterol, cardiolipin and phosphatidylserine with SLE disease activity. Taken together, these data suggest that lipid autoantigens represent a new family of biomarkers that can be employed to monitor disease activity plus the efficacy of therapeutic intervention in SLE.
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Affiliation(s)
- Vojislav Jovanović
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Nurhuda Abdul Aziz
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Yan Ting Lim
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Amanda Ng Ai Poh
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Sherlynn Jin Hui Chan
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Eliza Ho Xin Pei
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Fei Chuin Lew
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Guanghou Shui
- Department of Biochemistry, National University of Singapore, Singapore
| | - Andrew M. Jenner
- School of Biological Sciences, Illawara Health and Medical Research Institute, University of Wollongong, Australia
| | - Li Bowen
- Department of Biochemistry, National University of Singapore, Singapore
| | - Eoin F. McKinney
- Cambridge Institute for Medical Research, Cambridge, United Kingdom
- Department of Medicine, University of Cambridge, School of Clinical Medicine, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Paul A. Lyons
- Cambridge Institute for Medical Research, Cambridge, United Kingdom
- Department of Medicine, University of Cambridge, School of Clinical Medicine, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Michael D. Kemeny
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
| | - Kenneth G. C. Smith
- Cambridge Institute for Medical Research, Cambridge, United Kingdom
- Department of Medicine, University of Cambridge, School of Clinical Medicine, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Markus R. Wenk
- Department of Biochemistry, National University of Singapore, Singapore
| | - Paul A. MacAry
- Immunology Programme and Department of Microbiology, National University of Singapore, Singapore
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Grönwall C, Vas J, Silverman GJ. Protective Roles of Natural IgM Antibodies. Front Immunol 2012; 3:66. [PMID: 22566947 PMCID: PMC3341951 DOI: 10.3389/fimmu.2012.00066] [Citation(s) in RCA: 241] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 03/16/2012] [Indexed: 12/16/2022] Open
Abstract
Antibodies are a vital part of the armamentarium of the adaptive immune system for the fine-tuning of the recognition and response to foreign threats. However, in health there are some types of antibodies that instead recognize self-antigens and these contribute to the enhancement of primitive innate functions. This repertoire of natural IgM antibodies is postulated to have been selected during immune evolution for their contributions to critical immunoregulatory and housekeeping properties. The clearance of dying cells is one of the most essential responsibilities of the immune system, which is required to prevent uncontrolled inflammation and autoimmunity. In the murine immune system, natural IgM antibodies that recognize apoptotic cells have been shown to enhance the phagocytic clearance of dead and dying cells and to suppress innate immune signaling pathways. In the mouse, natural IgM are often the products of B-1 cell clones that arise during immune development without an absolute requirement for exogenous antigenic stimulation. In patients with systemic lupus erythematosus, IgM autoantibodies, which bind to neo-epitopes on apoptotic cells, have been demonstrated to be present at significantly higher levels in patients with lower disease activity and with less severe organ damage. While certain specificities of IgM autoantibodies correlate with protection from lupus renal disease, others may convey protective properties from lupus-associated atherosclerotic cardiovascular disease. New and unexpected insights into the functional roles of IgM antibodies are still emerging, especially regarding the functions of natural antibodies. Herein, we review recent progress in our understanding of the potential roles of natural IgM autoantibodies in the regulation of immune homeostasis and for protection from autoimmune and inflammatory diseases.
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Elkon KB, Silverman GJ. Naturally occurring autoantibodies to apoptotic cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 750:14-26. [PMID: 22903663 DOI: 10.1007/978-1-4614-3461-0_2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Subsets of IgM naturally occurring autoantibodies (NAbs) bind to the cell surface membranes of dying cells. The antibodies predominantly have specificities against lipid antigens or oxidized lipids. Chief among these lipid antigens are phosphorylcholine (PC) and malondialdehyde (MDA). Antibodies to negatively charged phospholipids such as phosphatidylserine (PS) have been described and there is controversy as to whether these antibodies are related to anticardiolipin antibodies observed in disease states. IgM NAbs that bind to apoptotic cells recruit classical complement pathway components and facilitate phagocytosis by both macrophages and dendritic cells, and may block inflammatory pathways. Under these circumstances, pathologic immune responses to self (autoimmunity) are avoided, whereas mice lacking serum IgM develop a lupus-like disease with associated IgG autoantibody responses. Based on these observations, IgM anti-PC NAbs were found to attenuate inflammation in mouse models of arthritis. IgMNAbs antibodies therefore appear to play pivotal roles in the dampening inflammation and maintenance of tolerance.
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Affiliation(s)
- Keith B Elkon
- Department of Medicine and Immunology, University of Washington, Seattle, Washington, USA.
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Kang YH, Urban BC, Sim RB, Kishore U. Human complement Factor H modulates C1q-mediated phagocytosis of apoptotic cells. Immunobiology 2011; 217:455-64. [PMID: 22088229 DOI: 10.1016/j.imbio.2011.10.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 10/04/2011] [Accepted: 10/18/2011] [Indexed: 11/19/2022]
Abstract
Complement is implicated in the clearance of apoptotic cells by phagocytes. Deficiencies in early complement components, particularly C1q, are associated with an increased risk of the development of systemic lupus erythematosus. C1q is considered to be important in this process through interaction with apoptotic cells and phagocytes. In the present study, we confirm that apoptotic cells are recognized not only by C1q but also by the complement regulatory protein Factor H. Both C1q and Factor H bind to apoptotic cells in a dose-dependent and saturable manner. We further examined the role of C1q and Factor H in the clearance of apoptotic cells by monocytes. C1q enhanced uptake/adhesion of apoptotic cells by monocytes whereas Factor H alone had no effect on this process. However, when both C1q and Factor H were present on the apoptotic cell surface, C1q-mediated enhancement of uptake/adhesion of the apoptotic cells by monocytes was reduced. This effect of Factor H also occurred if monocytes were pre-treated with Factor H, and then exposed to C1q-coated apoptotic cells. The results were consistent with Factor H interacting with monocytes through the integrin CD11b/CD18. We conclude that under physiological conditions, Factor H may be important in controlling the inflammation which might arise from C1q deposition on apoptotic cells.
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Affiliation(s)
- Yu-Hoi Kang
- MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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Alessandri C, Conti F, Pendolino M, Mancini R, Valesini G. New autoantigens in the antiphospholipid syndrome. Autoimmun Rev 2011; 10:609-16. [DOI: 10.1016/j.autrev.2011.04.011] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kishore U, Sim RB. Factor H as a regulator of the classical pathway activation. Immunobiology 2011; 217:162-8. [PMID: 21852018 DOI: 10.1016/j.imbio.2011.07.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 06/29/2011] [Accepted: 07/18/2011] [Indexed: 12/31/2022]
Abstract
C1q, the first subcomponent of the classical pathway, is a charge pattern recognition molecule that binds a diverse range of self, non-self and altered self ligands, leading to pro-inflammatory complement activation. Although complement is required for tissue homeostasis as well as defence against pathogens, exaggerated complement activation can be damaging to the tissue. Therefore, a fine balance between complement activation and inhibition is necessary. We have recently found that factor H, a polyanion recognition molecule and soluble regulator of alternative pathway activation in blood and on cell surfaces, can directly compete with C1q in binding to anionic phospholipids (cardiolipin), lipid A and Escherichia coli (three known activators of the classical pathway) and acts as a direct down regulator of the complement classical pathway. This ability of factor H to dampen classical pathway activation is distinct from its role as an alternative pathway down-regulator. Thus, by directly competing for specific C1q ligands (exogenous as well as endogenous), factor H is likely to be involved in fine-tuning and balancing the C1q-driven inflammatory processes in autoimmunity and infection. However, in the case of apoptotic cells, C1q-mediated enhancement of uptake/adhesion of the apoptotic cells by monocytes was reduced by factor H. Thus, factor H may be important in controlling the inflammation, which might arise from C1q deposition on apoptotic cells.
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Affiliation(s)
- Uday Kishore
- Centre for Infection, Immunity and Disease Mechanisms, Biosciences, School of Health Sciences and Social Care, Brunel University, Uxbridge, London, UK.
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Tan LA, Yu B, Sim FCJ, Kishore U, Sim RB. Complement activation by phospholipids: the interplay of factor H and C1q. Protein Cell 2010; 1:1033-49. [PMID: 21153520 DOI: 10.1007/s13238-010-0125-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2010] [Accepted: 10/17/2010] [Indexed: 10/18/2022] Open
Abstract
Complement proteins in blood recognize charged particles. The anionic phospholipid (aPL) cardiolipin binds both complement proteins C1q and factor H. C1q is an activator of the complement classical pathway, while factor H is an inhibitor of the alternative pathway. To examine opposing effects of C1q and factor H on complement activation by aPL, we surveyed C1q and factor H binding, and complement activation by aPL, either coated on microtitre plates or in liposomes. Both C1q and factor H bound to all aPL tested, and competed directly with each other for binding. All the aPL activated the complement classical pathway, but negligibly the alternative pathway, consistent with accepted roles of C1q and factor H. However, in this system, factor H, by competing directly with C1q for binding to aPL, acts as a direct regulator of the complement classical pathway. This regulatory mechanism is distinct from its action on the alternative pathway. Regulation of classical pathway activation by factor H was confirmed by measuring C4 activation by aPL in human sera in which the C1q:factor H molar ratio was adjusted over a wide range. Thus factor H, which is regarded as a down-regulator only of the alternative pathway, has a distinct role in downregulating activation of the classical complement pathway by aPL. A factor H homologue, β2-glycoprotein-1, also strongly inhibits C1q binding to cardiolipin. Recombinant globular domains of C1q A, B and C chains bound aPL similarly to native C1q, confirming that C1q binds aPL via its globular heads.
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Affiliation(s)
- Lee Aun Tan
- MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, South Parks Rd, Oxford OX13QU, UK
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Morlock G, Schwack W. Hyphenations in planar chromatography. J Chromatogr A 2010; 1217:6600-9. [DOI: 10.1016/j.chroma.2010.04.058] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2010] [Revised: 04/15/2010] [Accepted: 04/20/2010] [Indexed: 11/30/2022]
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Dynamic regulation of cardiolipin by the lipid pump Atp8b1 determines the severity of lung injury in experimental pneumonia. Nat Med 2010; 16:1120-1127. [PMID: 20852622 PMCID: PMC4500192 DOI: 10.1038/nm.2213] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 08/17/2010] [Indexed: 12/12/2022]
Abstract
Pneumonia remains the leading cause of infectious deaths and yet fundamentally new conceptual models underlying its pathogenesis have not emerged. Patients and mice with bacterial pneumonia have marked elevations of cardiolipin in lung fluid, a rare, mitochondrial-specific phospholipid that potently disrupts surfactant function. Intratracheal cardiolipin in mice recapitulates the clinical phenotype of pneumonia including impaired lung mechanics, modulation of cell survival and cytokine networks, and lobar consolidation. We have identified and characterized the activity of a novel cardiolipin transporter, ATP8b1, a mutant version of which is associated with severe pneumonia in humans and mice. ATP8b1 bound and internalized cardiolipin from extracellular fluid via a basic residue-enriched motif. Administration of cardiolipin binding motif peptide or ATP8b1 gene transfer in mice lessened lung injury and improved survival. The results unveil a new paradigm whereby ATP8b1 is a cardiolipin importer but its capacity to remove cardiolipin from lung fluid is exceeded during inflammation or ATP8b1 inefficiency. This discovery opens the door for new therapeutic strategies directed at modulating cardiolipin levels or its molecular interactions in pneumonia.
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Abstract
For several decades, allograft rejection was believed to be mediated almost exclusively by cellular immune responses, but it is now realized that humoral responses also play a major role. Although directed typically against donor human leukocyte antigen, it is becoming increasingly evident that the antibody response can also target autoantigens that are shared between donor and recipient and that this autoantibody may contribute to graft rejection. Many aspects of transplant-induced humoral autoimmunity remain poorly understood and key questions persist; not least what triggers the response and how autoantibody causes graft damage. Here, we collate results from recent clinical and experimental studies in transplantation and autoimmune diseases to propose answers to these questions.
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Weinhold K, Krause-Buchholz U, Rödel G, Kasper M, Barth K. Interaction and interrelation of P2X7 and P2X4 receptor complexes in mouse lung epithelial cells. Cell Mol Life Sci 2010; 67:2631-42. [PMID: 20405163 PMCID: PMC11115700 DOI: 10.1007/s00018-010-0355-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 03/15/2010] [Indexed: 12/14/2022]
Abstract
P2X4 and P2X7 receptors are ATP-gated ion channels that are co-expressed in alveolar epithelial type I cells. Both receptors are localized to the plasma membrane and partly associated with lipid rafts. Here we report on our study in an alveolar epithelial cell line of the molecular organization of P2X7R and P2X4R receptors and the effect of their knockdown. Native gel electrophoresis reveals three P2X7R complexes of approximately 430, approximately 580 and approximately 760 kDa. The latter two correspond exactly in size to signals of Cav-1, the structural protein of caveolae. Interestingly knockdown of P2rx7 affects protein levels, the intracellular distribution and the supramolecular organization of Cav-1 as well as of P2X4R, which is mainly detected in a complex of approximately 430 kDa. Our data suggest upregulation of P2X4R as a compensatory mechanism of P2X7R depletion.
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Affiliation(s)
- Karina Weinhold
- Institute of Anatomy, Medical Faculty of TU Dresden, Fetscherstraße 74, 01307 Dresden, Germany
| | | | - Gerhard Rödel
- Institute of Genetics, Faculty of Sciences of TU Dresden, Dresden, Germany
| | - Michael Kasper
- Institute of Anatomy, Medical Faculty of TU Dresden, Fetscherstraße 74, 01307 Dresden, Germany
| | - Kathrin Barth
- Institute of Anatomy, Medical Faculty of TU Dresden, Fetscherstraße 74, 01307 Dresden, Germany
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47
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Bruce JI. Plasma membrane calcium pump regulation by metabolic stress. World J Biol Chem 2010; 1:221-8. [PMID: 21537477 PMCID: PMC3083969 DOI: 10.4331/wjbc.v1.i7.221] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2010] [Revised: 06/30/2010] [Accepted: 07/07/2010] [Indexed: 02/05/2023] Open
Abstract
The plasma membrane Ca2+-ATPase (PMCA) is an ATP-driven pump that is critical for the maintenance of low resting [Ca2+]i in all eukaryotic cells. Metabolic stress, either due to inhibition of mitochondrial or glycolytic metabolism, has the capacity to cause ATP depletion and thus inhibit PMCA activity. This has potentially fatal consequences, particularly for non-excitable cells in which the PMCA is the major Ca2+ efflux pathway. This is because inhibition of the PMCA inevitably leads to cytosolic Ca2+ overload and the consequent cell death. However, the relationship between metabolic stress, ATP depletion and inhibition of the PMCA is not as simple as one would have originally predicted. There is increasing evidence that metabolic stress can lead to the inhibition of PMCA activity independent of ATP or prior to substantial ATP depletion. In particular, there is evidence that the PMCA has its own glycolytic ATP supply that can fuel the PMCA in the face of impaired mitochondrial function. Moreover, membrane phospholipids, mitochondrial membrane potential, caspase/calpain cleavage and oxidative stress have all been implicated in metabolic stress-induced inhibition of the PMCA. The major focus of this review is to challenge the conventional view of ATP-dependent regulation of the PMCA and bring together some of the alternative or additional mechanisms by which metabolic stress impairs PMCA activity resulting in cytosolic Ca2+ overload and cytotoxicity.
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Affiliation(s)
- Jason Ie Bruce
- Jason IE Bruce, Faculty of Life Sciences, The University of Manchester, Manchester M13 9NT, United Kingdom
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48
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Abstract
Antiphospholipid syndrome (APS) is an autoimmune disease characterized by arterial and venous thrombosis, recurrent abortions, and antiphospholipid antibodies (aPL). However, it is possible to find patients with clinical signs of APS who persistently test negative for aPL (seronegative APS, or SN-APS). The aim of this study was to identify new antigenic target(s) of autoantibodies in APS patients, which may also be recognized in SN-APS. We tested sera from patients with SN-APS with a proteomic approach by analyzing endothelial cell-surface membrane proteins. Sera from SN-APS patients revealed 2 reactive spots corresponding to vimentin, a protein that is shown to bind cardiolipin in vitro. Antivimentin/cardiolipin antibodies were tested in 29 SN-APS patients, 40 APS patients, 30 patients with systemic lupus erythematosus, 30 with rheumatoid arthritis, 30 with venous or arterial thrombosis, and 32 healthy control patients. We observed that not only a large proportion of SN-APS patients but also almost all the APS patients displayed the presence of antivimentin/cardiolipin antibodies. To verify the possible pathogenic role of these autoantibodies, we demonstrated that affinity-purified antivimentin/cardiolipin antibodies induced interleukin receptor-associated kinase phosphorylation and nuclear factor-κB activation in endothelial cells. Our results prompt to identify vimentin as a "new" cofactor for aPL, which may represent a useful tool mainly in SN-APS patients.
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Kahn P, Ramanujam M, Bethunaickan R, Huang W, Tao H, Madaio MP, Factor SM, Davidson A. Prevention of murine antiphospholipid syndrome by BAFF blockade. ACTA ACUST UNITED AC 2010; 58:2824-34. [PMID: 18759321 DOI: 10.1002/art.23764] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE This study was undertaken to determine whether BAFF blockade can be used to prevent or treat antiphospholipid syndrome in a mouse model. METHODS Eight- and 12-week-old (NZW x BXSB)F(1) mice were treated with BAFF-R-Ig or TACI-Ig alone or in addition to a short course of CTLA-4Ig. Mice were monitored for thrombocytopenia and proteinuria. Sera were tested for anticardiolipin antibodies (aCL), BAFF levels, and levels of soluble vascular cell adhesion molecule and E-selectin. Mice were killed at 17, 22, or 32 weeks of age, and kidneys and hearts were subjected to histologic examination. Spleen cells were phenotyped and enzyme-linked immunospot assays for autoantibody-producing B cells were performed. RESULTS Both BAFF-R-Ig and TACI-Ig prevented disease onset and significantly prolonged survival. Treated mice had significantly smaller spleens than controls, with fewer B cells and fewer activated and memory T cells. BAFF blockade did not prevent the development of aCL, and there was only a modest delay in the development of thrombocytopenia. However, treated mice had significantly less nephritis and myocardial infarcts than did controls. CONCLUSION Our findings suggest that aCL are generated in the germinal center, which is relatively independent of BAFF. Effector function of antiplatelet antibodies was only modestly affected by BAFF blockade. In contrast, myocardial infarctions were prevented, suggesting that triggering of thromboses requires both autoantibodies and mediators of inflammation. Similarly, renal damage requires both immune complexes and effector cells. The dissociation between autoantibody production and inflammation that may occur with B cell-depleting therapies underscores the role of B cells as effector cells in the autoimmune response.
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Affiliation(s)
- Philip Kahn
- Feinstein Institute for Medical Research, Manhasset, New York 11030, USA
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50
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Leffler J, Herbert AP, Norström E, Schmidt CQ, Barlow PN, Blom AM, Martin M. Annexin-II, DNA, and histones serve as factor H ligands on the surface of apoptotic cells. J Biol Chem 2010; 285:3766-3776. [PMID: 19951950 PMCID: PMC2823518 DOI: 10.1074/jbc.m109.045427] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 11/10/2009] [Indexed: 12/22/2022] Open
Abstract
Apoptotic cells are opsonized by complement components such as C1q and C3b, which increases their susceptibility to phagocytosis. Soluble complement inhibitors such as factor H (fH) also recognize apoptotic cells to minimize the pro-inflammatory effects of downstream complement activation. We used four radiolabeled protein constructs that span different regions of the 20 complement control protein (CCP) modules that make up fH and found that fragments comprising CCPs 6-8, CCPs 8-15, and CCPs 19-20 but not CCPs 1-4, bound to apoptotic Jurkat T cells. There are four possible ligand types on apoptotic cells that could recruit fH: proteins, carbohydrates, lipids, and DNA. We found that CCPs 6-8 of fH bind to annexin-II, a trypsin-insensitive protein that becomes exposed on surfaces of apoptotic cells. The second ligand of fH, which interacts with CCPs 6-8 and 19-20, is DNA. Confocal microscopy showed co-localization of fH with antibodies specific for DNA. fH also binds to histones devoid of DNA, and CCPs 1-4, 6-8, and 8-15 mediate this interaction. Treatment of apoptotic cells with neuraminidase, chondroitinase, heparitinase, and heparinase did not change fH binding. Treatment of apoptotic cells with phospholipase A(2) dramatically increased both binding of fH and cell-surface DNA. We also excluded the possibility that fH interacts with lysophospholipids using surface plasmon resonance and flow cytometry with lipid-coated beads. Identification of annexin-II as one of the fH ligands on apoptotic cells together with the fact that autoantibodies against annexin-II are found in systemic lupus erythematosus provides further insight into understanding the pathogenesis of this disease.
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Affiliation(s)
- Jonatan Leffler
- From the Department of Laboratory Medicine, Wallenberg Laboratory, University Hospital Malmö, Lund University, S-205 02 Malmö, Sweden and
| | - Andrew P Herbert
- the Edinburgh Biological NMR Unit, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland, United Kingdom
| | - Eva Norström
- From the Department of Laboratory Medicine, Wallenberg Laboratory, University Hospital Malmö, Lund University, S-205 02 Malmö, Sweden and
| | - Christoph Q Schmidt
- the Edinburgh Biological NMR Unit, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland, United Kingdom
| | - Paul N Barlow
- the Edinburgh Biological NMR Unit, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland, United Kingdom
| | - Anna M Blom
- From the Department of Laboratory Medicine, Wallenberg Laboratory, University Hospital Malmö, Lund University, S-205 02 Malmö, Sweden and.
| | - Myriam Martin
- From the Department of Laboratory Medicine, Wallenberg Laboratory, University Hospital Malmö, Lund University, S-205 02 Malmö, Sweden and
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