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Foskolou IP, Cunha PP, Sánchez-López E, Minogue EA, Nicolet BP, Guislain A, Jorgensen C, Kostidis S, Zandhuis ND, Barbieri L, Bargiela D, Nathanael D, Tyrakis PA, Palazon A, Giera M, Wolkers MC, Johnson RS. The two enantiomers of 2-hydroxyglutarate differentially regulate cytotoxic T cell function. Cell Rep 2023; 42:113013. [PMID: 37632752 DOI: 10.1016/j.celrep.2023.113013] [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: 09/19/2022] [Revised: 06/18/2023] [Accepted: 08/07/2023] [Indexed: 08/28/2023] Open
Abstract
2-Hydroxyglutarate (2HG) is a byproduct of the tricarboxylic acid (TCA) cycle and is readily detected in the tissues of healthy individuals. 2HG is found in two enantiomeric forms: S-2HG and R-2HG. Here, we investigate the differential roles of these two enantiomers in cluster of differentiation (CD)8+ T cell biology, where we find they have highly divergent effects on proliferation, differentiation, and T cell function. We show here an analysis of structural determinants that likely underlie these differential effects on specific α-ketoglutarate (αKG)-dependent enzymes. Treatment of CD8+ T cells with exogenous S-2HG, but not R-2HG, increased CD8+ T cell fitness in vivo and enhanced anti-tumor activity. These data show that S-2HG and R-2HG should be considered as two distinct and important actors in the regulation of T cell function.
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Affiliation(s)
- Iosifina P Foskolou
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK; Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden; Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory Amsterdam University Medical Center, University of Amsterdam, 1066 CX Amsterdam, the Netherlands; Oncode Institute, 3521 AL Utrecht, the Netherlands.
| | - Pedro P Cunha
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK; Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden
| | - Elena Sánchez-López
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333ZA Leiden, the Netherlands
| | - Eleanor A Minogue
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - Benoît P Nicolet
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory Amsterdam University Medical Center, University of Amsterdam, 1066 CX Amsterdam, the Netherlands; Oncode Institute, 3521 AL Utrecht, the Netherlands
| | - Aurélie Guislain
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory Amsterdam University Medical Center, University of Amsterdam, 1066 CX Amsterdam, the Netherlands; Oncode Institute, 3521 AL Utrecht, the Netherlands
| | - Christian Jorgensen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Sarantos Kostidis
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333ZA Leiden, the Netherlands
| | - Nordin D Zandhuis
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory Amsterdam University Medical Center, University of Amsterdam, 1066 CX Amsterdam, the Netherlands; Oncode Institute, 3521 AL Utrecht, the Netherlands
| | - Laura Barbieri
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - David Bargiela
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - Demitris Nathanael
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - Petros A Tyrakis
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - Asis Palazon
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK
| | - Martin Giera
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333ZA Leiden, the Netherlands
| | - Monika C Wolkers
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory Amsterdam University Medical Center, University of Amsterdam, 1066 CX Amsterdam, the Netherlands; Oncode Institute, 3521 AL Utrecht, the Netherlands
| | - Randall S Johnson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge CB2 3EG, UK; Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden.
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2
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Zagmignan A, Mendes YC, Mesquita GP, dos Santos GDC, Silva LDS, de Souza Sales AC, Castelo Branco SJDS, Junior ARC, Bazán JMN, Alves ER, de Almeida BL, Santos AKM, Firmo WDCA, Silva MRC, Cantanhede Filho AJ, de Miranda RDCM, da Silva LCN. Short-Term Intake of Theobroma grandiflorum Juice Fermented with Lacticaseibacillus rhamnosus ATCC 9595 Amended the Outcome of Endotoxemia Induced by Lipopolysaccharide. Nutrients 2023; 15:nu15041059. [PMID: 36839417 PMCID: PMC9962425 DOI: 10.3390/nu15041059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 02/23/2023] Open
Abstract
Endotoxemia is a condition caused by increasing levels of lipopolysaccharide (LPS) characterized by an impaired systemic response that causes multiple organ dysfunction. Lacticaseibacillus rhamnosus ATCC 9595 is a strain with probiotic potential which shows immunomodulatory properties. The incorporation of this bacterium in food rich in bioactive compounds, such as cupuaçu juice (Theobroma grandiflorum), could result in a product with interesting health properties. This work evaluated the effects of the oral administration of cupuaçu juice fermented with L. rhamnosus on the outcome of LPS-induced endotoxemia in mice. C57BL/6 mice (12/group) received oral doses (100 µL) of saline solution and unfermented or fermented cupuaçu juice (108 CFU/mL). After 5 days, the endotoxemia was induced by an intraperitoneal injection of LPS (10 mg/kg). The endotoxemia severity was evaluated daily using a score based on grooming behavior, mobility, presence of piloerection, and weeping eyes. After 6 h and 120 h, the mice (6/group) were euthanized for analysis of cell counts (in peritoneal lavage and serum) and organ weight. L. rhamnosus grew in cupuaçu juice and produced organic acids without the need for supplementation. The bacteria counts were stable in the juice during storage at 4 °C for 28 days. The fermentation with L. rhamnosus ATCC 9595 changed the metabolites profile of cupuaçu juice due to the biotransformation and enhancement of some compounds. In general, the administration of L. rhamnosus-fermented juice allowed a significant improvement in several characteristics of endotoxemic status (weight loss, hypothermia, severity index, cell migration). In addition, treatment with fermented juice significantly reduced the weight of the spleen, liver, intestine, and kidneys compared to the saline-treated endotoxemic group. Taken together, our data show that short-term intake therapy of cupuaçu juice fermented with L. rhamnosus ATCC 9595 can reduce systemic inflammation in an experimental model of LPS-induced endotoxemia in mice.
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Affiliation(s)
- Adrielle Zagmignan
- Laboratório de Patogenicidade Microbiana, Universidade CEUMA, São Luís 65075-120, Brazil
- Programa de Pós-Graduação em Gestão de Serviços e Programas de Saúde, Universidade CEUMA, São Luís 65075-120, Brazil
- Laboratório de Microbiologia Ambiental, Universidade CEUMA, São Luís 65075-120, Brazil
- Correspondence:
| | - Yasmim Costa Mendes
- Laboratório de Patogenicidade Microbiana, Universidade CEUMA, São Luís 65075-120, Brazil
| | | | | | - Lucas dos Santos Silva
- Laboratório de Patogenicidade Microbiana, Universidade CEUMA, São Luís 65075-120, Brazil
| | | | | | | | | | - Edinalva Rodrigues Alves
- Programa de Pós-Graduação em Gestão de Serviços e Programas de Saúde, Universidade CEUMA, São Luís 65075-120, Brazil
| | | | - Anne Karoline Maiorana Santos
- Laboratório de Extração e Cromatografia, Instituto Federal de Educação, Ciência e Tecnologia do Maranhão, Campus Monte Castelo, São Luís 65030-005, MA, Brazil
| | - Wellyson da Cunha Araújo Firmo
- Programa de Pós-Graduação em Gestão de Serviços e Programas de Saúde, Universidade CEUMA, São Luís 65075-120, Brazil
- Centro de Ciências da Saúde, Campus Imperatriz, Universidade Estadual da Região Tocantina do Maranhão, Imperatriz 65900-000, MA, Brazil
| | | | - Antônio José Cantanhede Filho
- Laboratório de Extração e Cromatografia, Instituto Federal de Educação, Ciência e Tecnologia do Maranhão, Campus Monte Castelo, São Luís 65030-005, MA, Brazil
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3
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Afsari F, McIntyre TM. D-2-Hydroxyglutarate Inhibits Calcineurin Phosphatase Activity to Abolish NF-AT Activation and IL-2 Induction in Stimulated Lymphocytes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:504-514. [PMID: 36602551 PMCID: PMC11071645 DOI: 10.4049/jimmunol.2200050] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 12/08/2022] [Indexed: 01/06/2023]
Abstract
Gliomas expressing mutant isocitrate dehydrogenases excessively synthesize d-2-hydroxyglutarate (D2HG), suppressing immune surveillance. A portion of this D2HG is released from these tumor cells, but the way environmental D2HG inhibits lymphocyte function is undefined. We incubated human PBLs or Jurkat T cells with D2HG at concentrations present within and surrounding gliomas or its obverse l-2-hydroxyglutarate (L2HG) stereoisomer. We quantified each 2HG stereoisomer within washed cells by N-(p-toluenesulfonyl)-l-phenylalanyl chloride derivatization with stable isotope-labeled D2HG and L2HG internal standards, HPLC separation, and mass spectrometry. D2HG was present in quiescent cells and was twice as abundant as L2HG. Extracellular 2HG rapidly increased intracellular levels of the provided stereoisomer by a stereoselective, concentration-dependent process. IL-2 expression, even when elicited by A23187 and PMA, was abolished by D2HG in a concentration-dependent manner, with significant reduction at just twice its basal level. In contrast, L2HG was only moderately inhibitory. IL-2 expression is regulated by increased intracellular Ca2+ that stimulates calcineurin to dephosphorylate cytoplasmic phospho-NF-AT, enabling its nuclear translocation. D2HG abolished stimulated expression of a stably integrated NF-AT-driven luciferase reporter that precisely paralleled its concentration-dependent inhibition of IL-2. D2HG did not affect intracellular Ca2+. Rather, surface plasmon resonance showed D2HG, but not L2HG, bound calcineurin, and D2HG, but not L2HG, inhibited Ca2+-dependent calcineurin phosphatase activity in stimulated Jurkat extracts. Thus, D2HG is a stereoselective calcineurin phosphatase inhibitor that prevents NF-AT dephosphorylation and so abolishes IL-2 transcription in stimulated lymphocytes. This occurs at D2HG concentrations found within and adjacent to gliomas independent of its metabolic or epigenetic transcriptional regulation.
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Affiliation(s)
- Faezeh Afsari
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH, USA
| | - Thomas M. McIntyre
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, OH, USA
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA
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4
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Metabolic Reprogramming in Cancer Cells: Emerging Molecular Mechanisms and Novel Therapeutic Approaches. Pharmaceutics 2022; 14:pharmaceutics14061303. [PMID: 35745875 PMCID: PMC9227908 DOI: 10.3390/pharmaceutics14061303] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/01/2022] [Accepted: 06/13/2022] [Indexed: 12/03/2022] Open
Abstract
The constant changes in cancer cell bioenergetics are widely known as metabolic reprogramming. Reprogramming is a process mediated by multiple factors, including oncogenes, growth factors, hypoxia-induced factors, and the loss of suppressor gene function, which support malignant transformation and tumor development in addition to cell heterogeneity. Consequently, this hallmark promotes resistance to conventional anti-tumor therapies by adapting to the drastic changes in the nutrient microenvironment that these therapies entail. Therefore, it represents a revolutionary landscape during cancer progression that could be useful for developing new and improved therapeutic strategies targeting alterations in cancer cell metabolism, such as the deregulated mTOR and PI3K pathways. Understanding the complex interactions of the underlying mechanisms of metabolic reprogramming during cancer initiation and progression is an active study field. Recently, novel approaches are being used to effectively battle and eliminate malignant cells. These include biguanides, mTOR inhibitors, glutaminase inhibition, and ion channels as drug targets. This review aims to provide a general overview of metabolic reprogramming, summarise recent progress in this field, and emphasize its use as an effective therapeutic target against cancer.
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5
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Peng S, Chen H, Chen L, Yang G, Liu J, Cheng X, Tang Y. Beyond Isocitrate Dehydrogenase Mutations: Emerging Mechanisms for the Accumulation of the Oncometabolite 2-Hydroxyglutarate. Chem Res Toxicol 2022; 35:115-124. [PMID: 35018778 DOI: 10.1021/acs.chemrestox.1c00254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2-Hydroxyglutarate (2-HG) is an unconventional oncometabolite of α-ketoglutarate. Isocitrate dehydrogenase mutation is generally acknowledged to be the main cause of 2-HG accumulation. In isocitrate dehydrogenase mutant tumors, 2-HG accumulation inhibits α-ketoglutarate/Fe(II)-dependent dioxygenases, resulting in epigenetic alterations. Recently, the increase of 2-HG has also been observed in the cases of mitochondrial dysfunction and hypoxia. In these cases, 2-HG not only inhibits α-ketoglutarate/Fe(II)-dependent dioxygenases to regulate epigenetics but also affects other cellular pathways, such as regulating hypoxia-inducible transcription factors and glycolysis. These provide a new perspective for the study of 2-HG.
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Affiliation(s)
- Shufen Peng
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Huimin Chen
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Li Chen
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Guang Yang
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jingjing Liu
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xueer Cheng
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuhan Tang
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Ministry of Education Key Laboratory of Environment, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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6
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Baek J, Pennathur S. Urinary 2-Hydroxyglutarate Enantiomers Are Markedly Elevated in a Murine Model of Type 2 Diabetic Kidney Disease. Metabolites 2021; 11:metabo11080469. [PMID: 34436410 PMCID: PMC8400583 DOI: 10.3390/metabo11080469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/11/2021] [Accepted: 07/16/2021] [Indexed: 12/23/2022] Open
Abstract
Metabolic reprogramming is a hallmark of diabetic kidney disease (DKD); nutrient overload leads to increased production of metabolic byproducts that may become toxic at high levels. One metabolic byproduct may be 2-hydroxyglutarate (2-HG), a metabolite with many regulatory functions that exists in both enantiomeric forms physiologically. We quantitatively determined the levels of L and D-2HG enantiomers in the urine, plasma, and kidney cortex of db/db mice, a pathophysiologically relevant murine model of type 2 diabetes and DKD. We found increased fractional excretion of both L and D-2HG enantiomers, suggesting increased tubular secretion and/or production of the two metabolites in DKD. Quantitation of TCA cycle metabolites in db/db cortex suggests that TCA cycle overload and an increase in 2-HG precursor substrate, α-ketoglutarate, drive the increased L and D-2HG production in DKD. In conclusion, we demonstrated increased 2-HG enantiomer production and urinary excretion in murine type 2 DKD, which may contribute to metabolic reprogramming and progression of diabetic kidney disease.
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Affiliation(s)
- Judy Baek
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48105, USA;
| | - Subramaniam Pennathur
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48105, USA;
- Division of Nephrology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48105, USA
- Correspondence:
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7
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Jang J, Song J, Sim I, Kwon YV, Yoon Y. Wnt-Signaling Inhibitor Wnt-C59 Suppresses the Cytokine Upregulation in Multiple Organs of Lipopolysaccharide-Induced Endotoxemic Mice via Reducing the Interaction between β-Catenin and NF-κB. Int J Mol Sci 2021; 22:ijms22126249. [PMID: 34200709 PMCID: PMC8230366 DOI: 10.3390/ijms22126249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/04/2021] [Accepted: 06/08/2021] [Indexed: 11/20/2022] Open
Abstract
Sepsis is characterized by multiple-organ dysfunction caused by the dysregulated host response to infection. Until now, however, the role of the Wnt signaling has not been fully characterized in multiple organs during sepsis. This study assessed the suppressive effect of a Wnt signaling inhibitor, Wnt-C59, in the kidney, lung, and liver of lipopolysaccharide-induced endotoxemic mice, serving as an animal model of sepsis. We found that Wnt-C59 elevated the survival rate of these mice and decreased their plasma levels of proinflammatory cytokines and organ-damage biomarkers, such as BUN, ALT, and AST. The Wnt/β-catenin and NF-κB pathways were stimulated and proinflammatory cytokines were upregulated in the kidney, lung, and liver of endotoxemic mice. Wnt-C59, as a Wnt signaling inhibitor, inhibited the Wnt/β-catenin pathway, and its interaction with the NF-κB pathway, which resulted in the inhibition of NF-κB activity and proinflammatory cytokine expression. In multiple organs of endotoxemic mice, Wnt-C59 significantly reduced the β-catenin level and interaction with NF-κB. Our findings suggest that the anti-endotoxemic effect of Wnt-C59 is mediated via reducing the interaction between β-catenin and NF-κB, consequently suppressing the associated cytokine upregulation in multiple organs. Thus, Wnt-C59 may be useful for the suppression of the multiple-organ dysfunction during sepsis.
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Affiliation(s)
- Jaewoong Jang
- Department of Microbiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea; (J.J.); (J.S.); (I.S.)
| | - Jaewon Song
- Department of Microbiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea; (J.J.); (J.S.); (I.S.)
| | - Inae Sim
- Department of Microbiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea; (J.J.); (J.S.); (I.S.)
| | - Young V. Kwon
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA;
| | - Yoosik Yoon
- Department of Microbiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea; (J.J.); (J.S.); (I.S.)
- Correspondence: ; Tel.: +82-10-4599-8231
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8
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Fitzpatrick SF, King AD, O'Donnell C, Roche HM, Ryan S. Mechanisms of intermittent hypoxia-mediated macrophage activation - potential therapeutic targets for obstructive sleep apnoea. J Sleep Res 2020; 30:e13202. [PMID: 32996666 DOI: 10.1111/jsr.13202] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/31/2020] [Accepted: 09/06/2020] [Indexed: 01/24/2023]
Abstract
Intermittent hypoxia (IH) plays a key role in the pathogenesis of insulin resistance (IR) in obstructive sleep apnoea (OSA). IH induces a pro-inflammatory phenotype of the adipose tissue with M1 macrophage polarisation, subsequently impeding adipocyte insulin signalling, and these changes are in striking similarity to those seen in obesity. However, the detailed molecular mechanisms of IH-induced macrophage polarisation are unknown and identification of same should lead to the identification of novel therapeutic targets. In the present study, we tested the hypothesis that IH acts through similar mechanisms as obesity, activating Toll-like-receptor (TLR)4/nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) signalling pathways leading to the upregulation and secretion of the key cytokines interleukin (IL)-1β and IL-6. Bone-marrow derived macrophages (BMDMs) from lean and obese C57BL/6 male mice were exposed to a state-of-the-art in vitro model of IH. Independent of obesity, IH led to a pro-inflammatory M1 phenotype characterised by increased inducible nitric oxide synthase and IL-6 mRNA expression, robust increase in NF-κB DNA-binding activity and IL-6 secretion. Furthermore, IH significantly increased pro-IL-1β mRNA and protein expression and mature IL-1β secretion compared to control treatment. Providing mechanistic insight, pre-treatment with the TLR4 specific inhibitor, TAK-242, prevented IH-induced M1 polarisation and upregulation of IL-1β mRNA and pro-IL-1β protein expression. Moreover, IH-induced increase in IL-1β secretion was prevented in BMDMs isolated from NLRP3 knockout mice. Thus, targeting TLR4/NF-κB and NLRP3 signalling pathways may provide novel therapeutic options for metabolic complications in OSA.
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Affiliation(s)
- Susan F Fitzpatrick
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland
| | - Ailbhe D King
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland
| | - Cliona O'Donnell
- Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland
| | - Helen M Roche
- Nutrigenomics Research Group, School of Public Health, Physiotherapy and Sports Science, UCD Institute of Food and Health, Diabetes Complications Research Centre, University College Dublin, Dublin, Ireland.,Institute for Global Food Security, Queen's University Belfast, Belfast, UK
| | - Silke Ryan
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland.,Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland
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