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Klement L, Jansakun C, Yan B, Staffer S, Tuma-Kellner S, Altamura S, Muckenthaler M, Merle U, Chamulitrat W. Myeloid-specific deletion of group VIA calcium-independent phospholipase A2 induces pro-inflammatory LPS response predominantly in male mice via MIP-1α activation. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167016. [PMID: 38198970 DOI: 10.1016/j.bbadis.2024.167016] [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: 06/29/2023] [Revised: 12/15/2023] [Accepted: 12/31/2023] [Indexed: 01/12/2024]
Abstract
Polymorphisms of group VIA calcium-independent phospholipase A2 (PLA2G6) are associated with blood C-reactive protein suggesting its role in inflammation. We showed that myeloid-specific Pla2g6-deficiency in Pla2g6M-/- mice led to exaggerated inflammation and fibrosis in a lean fatty liver model. We here investigated whether these mutants display alteration in immune response after treatment with E. coli lipopolysaccharides (LPS) under acute (a single dose) and persistent (four doses) conditions. Without LPS treatment, male Pla2g6M-/- (but not Flox) mice at 12 months of age exhibited splenomegaly and hepatic necrosis, and ~ 30 % of them exhibited autoimmune hepatitis showing lymphoplasma cells with CD3(+) and CD45R(+) staining. Under acute LPS, male mutants showed an elevation of plasma MIP-1α and immunoglobulinA as well as upregulation of hepatic apoptosis and fibrosis PARP-1, Bax, MCP-1, α-SMA, and collagen I proteins. Their bone-marrow-derived macrophages also showed an elevation of MIP-1α release upon LPS stimulation in vitro. Female mutants under acute LPS showed a moderate increase in plasma KC/CXCL1, MCP-1, and IL10, and they showed no remarkable increase in hepatic fibrosis under acute or persistent LPS. Male mutants under persistent LPS displayed an elevation of aspartate aminotransferase, blood eosinophils, and hepatic apoptosis. Moreover, ~30 % of these mutants exhibited eosinophilic sclerosing portal hepatitis associated with an upregulated protein expression of hepatic CD8α, CD68, eosinophilic cationic protein, and Ly6G. Thus, myeloid-PLA2G6 deficiency led to an autoimmune and LPS-induced inflammatory liver disease via MIP-1α in a male-predominant manner. Our results may be applicable to patients with PLA2G6 mutations who undergo bacterial infection and sepsis.
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Affiliation(s)
- Lukas Klement
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Chutima Jansakun
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80161, Thailand
| | - Bin Yan
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Simone Staffer
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Sabine Tuma-Kellner
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Sandro Altamura
- Department of Pediatric Oncology, Hematology and Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 350, 69120 Heidelberg, Germany
| | - Martina Muckenthaler
- Department of Pediatric Oncology, Hematology and Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 350, 69120 Heidelberg, Germany; Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), German Centre for Cardiovascular Research, Partner Site, University of Heidelberg, Germany
| | - Uta Merle
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Walee Chamulitrat
- Internal Medicine IV, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany.
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Yu C, Yin X, Li A, Li R, Yu H, Xing R, Liu S, Li P. Toxin metalloproteinases exert a dominant influence on pro-inflammatory response and anti-inflammatory regulation in jellyfish sting dermatitis. J Proteomics 2024; 292:105048. [PMID: 37981009 DOI: 10.1016/j.jprot.2023.105048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 11/21/2023]
Abstract
Toxin metalloproteinases are the primary components responsible for various toxicities in jellyfish venom, and there is still no effective specific therapy for jellyfish stings. The comprehension of the pathogenic mechanisms underlying toxin metalloproteinases necessitates further refinement. In this study, we conducted a differential analysis of a dermatitis mouse model induced by jellyfish Nemopilema nomurai venom (NnNV) samples with varying levels of metalloproteinase activity. Through skin tissue proteomics and serum metabolomics, the predominant influence of toxin metalloproteinase activity on inflammatory response was revealed, and the signal pathway involved in its regulation was identified. In skin tissues, many membrane proteins were significantly down-regulated, which might cause tissue damage. The expression of pro-inflammatory factors was mainly regulated by PI3K-Akt signaling pathway. In serum, many fatty acid metabolites were significantly down-regulated, which might be the anti-inflammation feedback regulated by NF-κB p65 signaling pathway. These results reveal the dermatitis mechanism of toxin metalloproteinases and provide new therapeutic targets for further studies. SIGNIFICANCE: Omics is an important method to analyze the pathological mechanism and discover the key markers, which can reveal the pathological characteristics of jellyfish stings. Our research first analyzed the impact of toxin metalloproteinases on jellyfish sting dermatitis by skin proteomics and serum metabolomics. The present results suggest that inhibition of toxin metalloproteinases may be an effective treatment strategy, and provide new references for further jellyfish sting studies.
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Affiliation(s)
- Chunlin Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiujing Yin
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Aoyu Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rongfeng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China
| | - Huahua Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China.
| | - Ronge Xing
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China
| | - Song Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China
| | - Pengcheng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao 266237, China
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Issara-Amphorn J, Sjoelund VH, Smelkinson M, Montalvo S, Yoon SH, Manes NP, Nita-Lazar A. Myristoylated, alanine-rich C-kinase substrate (MARCKS) regulates toll-like receptor 4 signaling in macrophages. Sci Rep 2023; 13:19562. [PMID: 37949888 PMCID: PMC10638260 DOI: 10.1038/s41598-023-46266-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023] Open
Abstract
MARCKS (myristoylated alanine-rich C-kinase substrate) is a membrane-associated protein expressed in many cell types, including macrophages. MARCKS is functionally implicated in cell adhesion, phagocytosis, and inflammation. LPS (lipopolysaccharide) triggers inflammation via TLR4 (toll-like receptor 4).The presence of MARCKS and the formation of phospho-MARCKS in various cell types have been described, but the role(s) of MARCKS in regulating macrophage functions remain unclear. We investigated the role of MARCKS in inflammation. Confocal microscopy revealed that MARCKS and phospho-MARCKS increased localization to endosomes and the Golgi apparatus upon LPS stimulation.CRISPR-CAS9 mediated knockout of MARCKS in macrophages downregulated the production of TNF and IL6, suggesting a role for MARCKS in inflammatory responses. Our comprehensive proteomics analysis together with real-time metabolic assays comparing LPS-stimulation of WT and MARCKS knock-out macrophages provided insights into the involvement of MARCKS in specific biological processes including innate immune response, inflammatory response, cytokine production, and molecular functions such as extracellularly ATP-gated cation channel activity, electron transfer activity and oxidoreductase activity, uncovering specific proteins involved in regulating MARCKS activity upon LPS stimulation. MARCKS appears to be a key regulator of inflammation whose inhibition might be beneficial for therapeutic intervention in inflammatory diseases.
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Affiliation(s)
- Jiraphorn Issara-Amphorn
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA
| | - Virginie H Sjoelund
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA
- Barnett Institute, Northeastern University, Boston, MA, 02115, USA
| | - Margery Smelkinson
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sebastian Montalvo
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA
| | - Sung Hwan Yoon
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA
| | - Nathan P Manes
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA
| | - Aleksandra Nita-Lazar
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892-1892, USA.
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Ghorbani P, Kim SY, Smith TKT, Minarrieta L, Robert-Gostlin V, Kilgour MK, Ilijevska M, Alecu I, Snider SA, Margison KD, Nunes JRC, Woo D, Pember C, O’Dwyer C, Ouellette J, Kotchetkov P, St-Pierre J, Bennett SAL, Lacoste B, Blais A, Nair MG, Fullerton MD. Choline metabolism underpins macrophage IL-4 polarization and RELMα up-regulation in helminth infection. PLoS Pathog 2023; 19:e1011658. [PMID: 37747879 PMCID: PMC10553840 DOI: 10.1371/journal.ppat.1011658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 10/05/2023] [Accepted: 09/05/2023] [Indexed: 09/27/2023] Open
Abstract
Type 2 cytokines like IL-4 are hallmarks of helminth infection and activate macrophages to limit immunopathology and mediate helminth clearance. In addition to cytokines, nutrients and metabolites critically influence macrophage polarization. Choline is an essential nutrient known to support normal macrophage responses to lipopolysaccharide; however, its function in macrophages polarized by type 2 cytokines is unknown. Using murine IL-4-polarized macrophages, targeted lipidomics revealed significantly elevated levels of phosphatidylcholine, with select changes to other choline-containing lipid species. These changes were supported by the coordinated up-regulation of choline transport compared to naïve macrophages. Pharmacological inhibition of choline metabolism significantly suppressed several mitochondrial transcripts and dramatically inhibited select IL-4-responsive transcripts, most notably, Retnla. We further confirmed that blocking choline metabolism diminished IL-4-induced RELMα (encoded by Retnla) protein content and secretion and caused a dramatic reprogramming toward glycolytic metabolism. To better understand the physiological implications of these observations, naïve or mice infected with the intestinal helminth Heligmosomoides polygyrus were treated with the choline kinase α inhibitor, RSM-932A, to limit choline metabolism in vivo. Pharmacological inhibition of choline metabolism lowered RELMα expression across cell-types and tissues and led to the disappearance of peritoneal macrophages and B-1 lymphocytes and an influx of infiltrating monocytes. The impaired macrophage activation was associated with some loss in optimal immunity to H. polygyrus, with increased egg burden. Together, these data demonstrate that choline metabolism is required for macrophage RELMα induction, metabolic programming, and peritoneal immune homeostasis, which could have important implications in the context of other models of infection or cancer immunity.
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Affiliation(s)
- Peyman Ghorbani
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Sang Yong Kim
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, California, United States of America
| | - Tyler K. T. Smith
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Lucía Minarrieta
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Victoria Robert-Gostlin
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Marisa K. Kilgour
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
| | - Maja Ilijevska
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
| | - Irina Alecu
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Shayne A. Snider
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Kaitlyn D. Margison
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Julia R. C. Nunes
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Daniel Woo
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, California, United States of America
| | - Ciara Pember
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
| | - Conor O’Dwyer
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Julie Ouellette
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Pavel Kotchetkov
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Julie St-Pierre
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Steffany A. L. Bennett
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario, Canada
- University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Baptiste Lacoste
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Alexandre Blais
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
- University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario, Canada
- Éric Poulin Centre for Neuromuscular Disease, Ottawa, Ontario, Canada
| | - Meera G. Nair
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, California, United States of America
| | - Morgan D. Fullerton
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario, Canada
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5
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Issara-Amphorn J, Sjoelund V, Smelkinson M, Yoon SH, Manes NP, Nita-Lazar A. Myristoylated, Alanine-rich C-kinase Substrate (MARCKS) regulates Toll-like receptor 4 signaling in macrophages. RESEARCH SQUARE 2023:rs.3.rs-3094036. [PMID: 37790394 PMCID: PMC10543024 DOI: 10.21203/rs.3.rs-3094036/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
MARCKS (Myristoylated Alanine-rich C-kinase Substrate) is a membrane protein expressed in many cell types, including macrophages. MARCKS is functionally implicated in cell adhesion, phagocytosis, and inflammation. LPS (lipopolysaccharide) triggers inflammation via TLR4 (Toll-like receptor 4). The presence of MARCKS and the formation of phospho-MARCKS in macrophages have been described, but the role(s) of MARCKS in regulating macrophage functions remain unclear. To investigate the role of MARCKS during inflammation, we activated macrophages using LPS with or without the addition of a PKC inhibitor. We found that PKC inhibition substantially decreased macrophage IL6 and TNF cytokine production. In addition, confocal microscopy revealed that MARCKS and phospho-MARCKS increased localization to endosomes and the Golgi apparatus upon LPS stimulation. CRISPR-CAS9 mediated knockout of MARCKS in macrophages downregulated TNF and IL6 production, suggesting a role for MARCKS in inflammatory responses. Our comprehensive proteomics analysis together with real-time metabolic assays comparing LPS-stimulation of WT and MARCKS knock-out macrophages provided insights into the involvement of MARCKS in specific biological processes and signaling pathways, uncovering specific proteins involved in regulating MARCKS activity upon LPS stimulation. MARCKS appears to be a key regulator of inflammation whose inhibition might be beneficial for therapeutic intervention in inflammatory related diseases.
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6
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Muto E, Okada T, Yamanaka T, Uchino H, Inazu M. Licochalcone E, a β-Amyloid Aggregation Inhibitor, Regulates Microglial M1/M2 Polarization via Inhibition of CTL1-Mediated Choline Uptake. Biomolecules 2023; 13:biom13020191. [PMID: 36830561 PMCID: PMC9953043 DOI: 10.3390/biom13020191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 01/19/2023] Open
Abstract
Alzheimer's disease (AD) is thought to be a series of neuroinflammatory diseases caused by abnormal deposits of amyloid-β (Aβ) and tau protein in the brain as part of its etiology. We focused on Aβ aggregation and M1 and M2 microglial polarity in microglia to search for novel therapeutic agents. It has been reported that the inhibition of choline uptake via choline transporter-like protein 1 (CTL1) in microglia preferentially induces M2 microglial polarity. However, the role of the choline transport system on the regulation of microglial M1/M2 polarity in AD is not fully understood. Licochalcones (Licos) A-E, flavonoids extracted from licorice, have been reported to have immunological anti-inflammatory effects, and Lico A inhibits Aβ aggregation. In this study, we compared the efficacy of five Licos, from Lico A to E, at inhibiting Aβ1-42 aggregation. Among the five Licos, Lico E was selected to investigate the relationship between the inhibition of choline uptake and microglial M1/M2 polarization using the immortalized mouse microglial cell line SIM-A9. We newly found that Lico E inhibited choline uptake and Aβ1-42 aggregation in SIM-A9 cells in a concentration-dependent manner, suggesting that the inhibitory effect of Lico E on choline uptake is mediated by CTL1. The mRNA expression of tumor necrosis factor (TNF-α), a marker of M1 microglia, was increased by Aβ1-42, and its effect was inhibited by choline deprivation and Lico E in a concentration-dependent manner. In contrast, the mRNA expression of arginase-1 (Arg-1), a marker of M2 microglia, was increased by IL-4, and its effect was enhanced by choline deprivation and Lico E. We found that Lico E has an inhibitory effect on Aβ aggregation and promotes polarity from M1 to M2 microglia via inhibition of the CTL1 function in microglia. Thus, Lico E may become a leading compound for a novel treatment of AD.
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Affiliation(s)
- Eisuke Muto
- Department of Anesthesiology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Toshio Okada
- Department of Anesthesiology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Tsuyoshi Yamanaka
- Department of Molecular Preventive Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo 160-8402, Japan
| | - Hiroyuki Uchino
- Department of Anesthesiology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Masato Inazu
- Department of Molecular Preventive Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo 160-8402, Japan
- Institute of Medical Science, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo 160-8402, Japan
- Correspondence: ; Tel.: +81-3-3351-6141
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7
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Miriam Jose A, Rasool M. Choline kinase: An underappreciated rheumatoid arthritis therapeutic target. Life Sci 2022; 309:121031. [DOI: 10.1016/j.lfs.2022.121031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/28/2022] [Accepted: 09/30/2022] [Indexed: 11/15/2022]
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8
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Functional Expression of Choline Transporters in Microglia and Their Regulation of Microglial M1/M2 Polarization. Int J Mol Sci 2022; 23:ijms23168924. [PMID: 36012189 PMCID: PMC9408370 DOI: 10.3390/ijms23168924] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/04/2022] [Accepted: 08/09/2022] [Indexed: 12/24/2022] Open
Abstract
Background: Microglia are key cells of the immune system in the central nervous system and are suggested to be deeply involved in the development of neurodegenerative diseases. It is well known that microglia have functional plasticity, with an inflammatory M1 phenotype and an anti-inflammatory M2 phenotype. Inhibition of choline transport in macrophages has been reported to suppress the secretion of inflammatory cytokines. However, the role of the choline transport system in regulating microglial M1/M2 polarization has not been fully elucidated to date. In this study, we investigated the mechanism of choline uptake in microglia, and its association with microglial M1/M2 polarization. Methods: The immortalized mouse microglial cell line SIM-A9 was used for [3H]choline uptake and expression analysis of choline transporters. The association between the choline uptake system and the M1/M2 polarization of microglia was also analyzed. Results: Choline transporter-like protein (CTL) 1 and CTL2 were highly expressed in SIM-A9 cells, and CTL1 and CTL2 were localized in the plasma membrane and mitochondria, respectively. Functional analysis of choline uptake demonstrated the existence of Na+-independent, pH-dependent, and intermediate-affinity choline transport systems. Choline uptake was concentration-dependently inhibited by hemicholinium-3 (HC-3), an inhibitor of choline uptake, and increased by lipopolysaccharide (LPS) and interleukin-4 (IL-4). Expression of the mRNA of M1 microglia markers IL-1β and IL-6 was increased by LPS, and their effects were suppressed by choline deprivation and HC-3. In contrast, mRNA expression of the M2 microglial marker arginase-1 (Arg-1) was increased by IL-4, and the effect was enhanced by choline deprivation and HC-3. Conclusions: Our results suggest that inhibition of CTL1-mediated choline uptake in microglia preferentially induces M2 microglia polarization, which is a potential therapeutic approach for inflammatory brain diseases.
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Kubo S, Fritz JM, Raquer-McKay HM, Kataria R, Vujkovic-Cvijin I, Al-Shaibi A, Yao Y, Zheng L, Zou J, Waldman AD, Jing X, Farley TK, Park AY, Oler AJ, Charles AK, Makhlouf M, AbouMoussa EH, Hasnah R, Saraiva LR, Ganesan S, Al-Subaiey AA, Matthews H, Flano E, Lee HH, Freeman AF, Sefer AP, Sayar E, Çakır E, Karakoc-Aydiner E, Baris S, Belkaid Y, Ozen A, Lo B, Lenardo MJ. Congenital iRHOM2 deficiency causes ADAM17 dysfunction and environmentally directed immunodysregulatory disease. Nat Immunol 2022; 23:75-85. [PMID: 34937930 PMCID: PMC11060421 DOI: 10.1038/s41590-021-01093-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 11/09/2021] [Indexed: 11/08/2022]
Abstract
We report a pleiotropic disease due to loss-of-function mutations in RHBDF2, the gene encoding iRHOM2, in two kindreds with recurrent infections in different organs. One patient had recurrent pneumonia but no colon involvement, another had recurrent infectious hemorrhagic colitis but no lung involvement and the other two experienced recurrent respiratory infections. Loss of iRHOM2, a rhomboid superfamily member that regulates the ADAM17 metalloproteinase, caused defective ADAM17-dependent cleavage and release of cytokines, including tumor-necrosis factor and amphiregulin. To understand the diverse clinical phenotypes, we challenged Rhbdf2-/- mice with Pseudomonas aeruginosa by nasal gavage and observed more severe pneumonia, whereas infection with Citrobacter rodentium caused worse inflammatory colitis than in wild-type mice. The fecal microbiota in the colitis patient had characteristic oral species that can predispose to colitis. Thus, a human immunodeficiency arising from iRHOM2 deficiency causes divergent disease phenotypes that can involve the local microbial environment.
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Affiliation(s)
- Satoshi Kubo
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jill M Fritz
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Cooley, LLP in Washington, Washington, DC, USA
| | - Hayley M Raquer-McKay
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Immunology Program, Stanford University School of Medicine, Stanford, CA, USA
| | - Rhea Kataria
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ivan Vujkovic-Cvijin
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- F. Widjaja Foundation Inflammatory Bowel and Immunobiology Research Institute and Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | - Yikun Yao
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Lixin Zheng
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Juan Zou
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alex D Waldman
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Xinyi Jing
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Taylor K Farley
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Ann Y Park
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Andrew J Oler
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | | | | | - Reem Hasnah
- Research Branch, Sidra Medicine, Doha, Qatar
| | - Luis R Saraiva
- Research Branch, Sidra Medicine, Doha, Qatar
- Monell Chemical Senses Center, Philadelphia, PA, USA
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
| | - Sundar Ganesan
- Biological Imaging Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | - Helen Matthews
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Emilio Flano
- Discovery Oncology and Immunology, Merck & Co., Inc., Boston, MA, USA
| | - Hyun Hee Lee
- Discovery Oncology and Immunology, Merck & Co., Inc., Boston, MA, USA
| | - Alexandra F Freeman
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Asena Pınar Sefer
- Division of Allergy and Immunology, Marmara University School of Medicine, Istanbul, Turkey
- Istanbul Jeffrey Modell Diagnostic Center for Primary Immunodeficiency Diseases, Istanbul, Turkey
- The Isil Berat Barlan Center for Translational Medicine, Istanbul, Turkey
| | - Ersin Sayar
- Department of Pediatric Gastroenterology, Altinbas University Medical Park Bahcelievler Hospital, Istanbul, Turkey
| | - Erkan Çakır
- Division of Pediatric Pulmonology, Department of Pediatrics, Bezmialem Vakif University, School of Medicine, Istanbul, Turkey
| | - Elif Karakoc-Aydiner
- Division of Allergy and Immunology, Marmara University School of Medicine, Istanbul, Turkey
- Istanbul Jeffrey Modell Diagnostic Center for Primary Immunodeficiency Diseases, Istanbul, Turkey
- The Isil Berat Barlan Center for Translational Medicine, Istanbul, Turkey
| | - Safa Baris
- Division of Allergy and Immunology, Marmara University School of Medicine, Istanbul, Turkey
- Istanbul Jeffrey Modell Diagnostic Center for Primary Immunodeficiency Diseases, Istanbul, Turkey
- The Isil Berat Barlan Center for Translational Medicine, Istanbul, Turkey
| | - Yasmine Belkaid
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- National Institute of Allergy and Infectious Diseases Microbiome Program, National Institutes of Health, Bethesda, MD, USA
| | - Ahmet Ozen
- Division of Allergy and Immunology, Marmara University School of Medicine, Istanbul, Turkey.
- Istanbul Jeffrey Modell Diagnostic Center for Primary Immunodeficiency Diseases, Istanbul, Turkey.
- The Isil Berat Barlan Center for Translational Medicine, Istanbul, Turkey.
| | - Bernice Lo
- Research Branch, Sidra Medicine, Doha, Qatar.
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar.
| | - Michael J Lenardo
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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10
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FATP4 inactivation in cultured macrophages attenuates M1- and ER stress-induced cytokine release via a metabolic shift towards triacylglycerides. Biochem J 2021; 478:1861-1877. [PMID: 33900381 DOI: 10.1042/bcj20210155] [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: 03/15/2021] [Revised: 04/16/2021] [Accepted: 04/26/2021] [Indexed: 12/15/2022]
Abstract
Fatty acid transport protein 4 (FATP4) belongs to a family of acyl-CoA synthetases which activate long-chain fatty acids into acyl-CoAs subsequently used in specific metabolic pathways. Patients with FATP4 mutations and Fatp4-null mice show thick desquamating skin and other complications, however, FATP4 role on macrophage functions has not been studied. We here determined whether the levels of macrophage glycerophospholipids, sphingolipids including ceramides, triacylglycerides, and cytokine release could be altered by FATP4 inactivation. Two in vitro experimental systems were studied: FATP4 knockdown in THP-1-derived macrophages undergoing M1 (LPS + IFNγ) or M2 (IL-4) activation and bone marrow-derived macrophages (BMDMs) from macrophage-specific Fatp4-knockout (Fatp4M-/-) mice undergoing tunicamycin (TM)-induced endoplasmic reticulum stress. FATP4-deficient macrophages showed a metabolic shift towards triacylglycerides and were protected from M1- or TM-induced release of pro-inflammatory cytokines and cellular injury. Fatp4M-/- BMDMs showed specificity in attenuating TM-induced activation of inositol-requiring enzyme1α, but not other unfolded protein response pathways. Under basal conditions, FATP4/Fatp4 deficiency decreased the levels of ceramides and induced an up-regulation of mannose receptor CD206 expression. The deficiency led to an attenuation of IL-8 release in THP-1 cells as well as TNF-α and IL-12 release in BMDMs. Thus, FATP4 functions as an acyl-CoA synthetase in macrophages and its inactivation suppresses the release of pro-inflammatory cytokines by shifting fatty acids towards the synthesis of specific lipids.
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11
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Parab AR, Thomas D, Lostracco-Johnson S, Siqueira-Neto JL, McKerrow JH, Dorrestein PC, McCall LI. Dysregulation of Glycerophosphocholines in the Cutaneous Lesion Caused by Leishmania major in Experimental Murine Models. Pathogens 2021; 10:593. [PMID: 34068119 PMCID: PMC8152770 DOI: 10.3390/pathogens10050593] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/06/2021] [Accepted: 05/10/2021] [Indexed: 01/21/2023] Open
Abstract
Cutaneous leishmaniasis (CL) is the most common disease form caused by a Leishmania parasite infection and considered a neglected tropical disease (NTD), affecting 700,000 to 1.2 million new cases per year in the world. Leishmania major is one of several different species of the Leishmania genus that can cause CL. Current CL treatments are limited by adverse effects and rising resistance. Studying disease metabolism at the site of infection can provide knowledge of new targets for host-targeted drug development. In this study, tissue samples were collected from mice infected in the ear or footpad with L. major and analyzed by untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS). Significant differences in overall metabolite profiles were noted in the ear at the site of the lesion. Interestingly, lesion-adjacent, macroscopically healthy sites also showed alterations in specific metabolites, including selected glycerophosphocholines (PCs). Host-derived PCs in the lower m/z range (m/z 200-799) showed an increase with infection in the ear at the lesion site, while those in the higher m/z range (m/z 800-899) were decreased with infection at the lesion site. Overall, our results expanded our understanding of the mechanisms of CL pathogenesis through host metabolism and may lead to new curative measures against infection with Leishmania.
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Affiliation(s)
- Adwaita R. Parab
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK 73019, USA;
- Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma, Norman, OK 73019, USA
| | - Diane Thomas
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; (D.T.); (S.L.-J.); (J.L.S.-N.); (J.H.M.); (P.C.D.)
| | - Sharon Lostracco-Johnson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; (D.T.); (S.L.-J.); (J.L.S.-N.); (J.H.M.); (P.C.D.)
| | - Jair L. Siqueira-Neto
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; (D.T.); (S.L.-J.); (J.L.S.-N.); (J.H.M.); (P.C.D.)
| | - James H. McKerrow
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; (D.T.); (S.L.-J.); (J.L.S.-N.); (J.H.M.); (P.C.D.)
| | - Pieter C. Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; (D.T.); (S.L.-J.); (J.L.S.-N.); (J.H.M.); (P.C.D.)
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA 92093, USA
- Collaborative Mass Spectrometry Innovation Center, University of California San Diego, La Jolla, CA 92093, USA
| | - Laura-Isobel McCall
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK 73019, USA;
- Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma, Norman, OK 73019, USA
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
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12
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Candida Administration in Bilateral Nephrectomy Mice Elevates Serum (1→3)-β-D-glucan That Enhances Systemic Inflammation Through Energy Augmentation in Macrophages. Int J Mol Sci 2021; 22:ijms22095031. [PMID: 34068595 PMCID: PMC8126065 DOI: 10.3390/ijms22095031] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/18/2021] [Accepted: 04/29/2021] [Indexed: 12/15/2022] Open
Abstract
Systemic inflammation, from gut translocation of organismal molecules, might worsen uremic complications in acute kidney injury (AKI). The monitoring of gut permeability integrity and/or organismal molecules in AKI might be clinically beneficial. Due to the less prominence of Candida albicans in human intestine compared with mouse gut, C. albicans were orally administered in bilateral nephrectomy (BiN) mice. Gut dysbiosis, using microbiome analysis, and gut permeability defect (gut leakage), which was determined by fluorescein isothiocyanate-dextran and intestinal tight-junction immunofluorescent staining, in mice with BiN-Candida was more severe than BiN without Candida. Additionally, profound gut leakage in BiN-Candida also resulted in gut translocation of lipopolysaccharide (LPS) and (1→3)-β-D-glucan (BG), the organismal components from gut contents, that induced more severe systemic inflammation than BiN without Candida. The co-presentation of LPS and BG in mouse serum enhanced inflammatory responses. As such, LPS with Whole Glucan Particle (WGP, a representative BG) induced more severe macrophage responses than LPS alone as determined by supernatant cytokines and gene expression of downstream signals (NFκB, Malt-1 and Syk). Meanwhile, WGP alone did not induced the responses. In parallel, WGP (with or without LPS), but not LPS alone, accelerated macrophage ATP production (extracellular flux analysis) through the upregulation of genes in mitochondria and glycolysis pathway (using RNA sequencing analysis), without the induction of cell activities. These data indicated a WGP pre-conditioning effect on cell energy augmentation. In conclusion, Candida in BiN mice accelerated gut translocation of BG that augmented cell energy status and enhanced pro-inflammatory macrophage responses. Hence, gut fungi and BG were associated with the enhanced systemic inflammation in acute uremia.
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13
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Quiroga IY, Pellon-Maison M, Gonzalez MC, Coleman RA, Gonzalez-Baro MR. Triacylglycerol synthesis directed by glycerol-3-phosphate acyltransferases -3 and -4 is required for lipid droplet formation and the modulation of the inflammatory response during macrophage to foam cell transition. Atherosclerosis 2021; 316:1-7. [PMID: 33260006 PMCID: PMC7803380 DOI: 10.1016/j.atherosclerosis.2020.11.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 10/21/2020] [Accepted: 11/19/2020] [Indexed: 01/18/2023]
Abstract
BACKGROUND AND AIMS The transition of macrophage to foam cells is a major hallmark of early stage atherosclerotic lesions. This process is characterized by the accumulation of large cytoplasmic lipid droplets containing large quantities of cholesterol esters (CE), triacylglycerol (TAG) and phospholipid (PL). Although cholesterol and CE metabolism during foam cell formation has been broadly studied, little is known about the role of the glycerolipids (TAG and PL) in this context. Here we studied the contribution of glycerolipid synthesis to lipid accumulation, focusing specifically on the first and rate-limiting enzyme of the pathway: glycerol-3-phosphate acyltransferase (GPAT). METHODS We used RAW 264.7 cells and bone marrow derived macrophages (BMDM) treated with oxidized LDL (oxLDL). RESULTS We showed that TAG synthesis is induced during the macrophage to foam cell transition. The expression and activity of GPAT3 and GPAT4 also increased during this process, and these two isoforms were required for the accumulation of cell TAG and PL. Compared to cells from wildtype mice after macrophage to foam cell transition, Gpat4-/- BMDM released more pro-inflammatory cytokines and chemokines, suggesting that the activity of GPAT4 could be associated with a decrease in the inflammatory response, probably by sequestering signaling precursors into lipid droplets. CONCLUSIONS Our results provide evidence that TAG synthesis directed by GPAT3 and GPAT4 is required for lipid droplet formation and the modulation of the inflammatory response during the macrophage-foam cell transition.
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Affiliation(s)
- Ivana Y Quiroga
- Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, 1900, Argentina
| | - Magali Pellon-Maison
- Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, 1900, Argentina
| | - Marina C Gonzalez
- Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, 1900, Argentina
| | - Rosalind A Coleman
- Department of Nutrition, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Maria R Gonzalez-Baro
- Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, 1900, Argentina.
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14
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Martínez BA, Hoyle RG, Yeudall S, Granade ME, Harris TE, Castle JD, Leitinger N, Bland ML. Innate immune signaling in Drosophila shifts anabolic lipid metabolism from triglyceride storage to phospholipid synthesis to support immune function. PLoS Genet 2020; 16:e1009192. [PMID: 33227003 PMCID: PMC7721134 DOI: 10.1371/journal.pgen.1009192] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 12/07/2020] [Accepted: 10/13/2020] [Indexed: 02/07/2023] Open
Abstract
During infection, cellular resources are allocated toward the metabolically-demanding processes of synthesizing and secreting effector proteins that neutralize and kill invading pathogens. In Drosophila, these effectors are antimicrobial peptides (AMPs) that are produced in the fat body, an organ that also serves as a major lipid storage depot. Here we asked how activation of Toll signaling in the larval fat body perturbs lipid homeostasis to understand how cells meet the metabolic demands of the immune response. We find that genetic or physiological activation of fat body Toll signaling leads to a tissue-autonomous reduction in triglyceride storage that is paralleled by decreased transcript levels of the DGAT homolog midway, which carries out the final step of triglyceride synthesis. In contrast, Kennedy pathway enzymes that synthesize membrane phospholipids are induced. Mass spectrometry analysis revealed elevated levels of major phosphatidylcholine and phosphatidylethanolamine species in fat bodies with active Toll signaling. The ER stress mediator Xbp1 contributed to the Toll-dependent induction of Kennedy pathway enzymes, which was blunted by deleting AMP genes, thereby reducing secretory demand elicited by Toll activation. Consistent with ER stress induction, ER volume is expanded in fat body cells with active Toll signaling, as determined by transmission electron microscopy. A major functional consequence of reduced Kennedy pathway induction is an impaired immune response to bacterial infection. Our results establish that Toll signaling induces a shift in anabolic lipid metabolism to favor phospholipid synthesis and ER expansion that may serve the immediate demand for AMP synthesis and secretion but with the long-term consequence of insufficient nutrient storage.
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Affiliation(s)
- Brittany A. Martínez
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Rosalie G. Hoyle
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Scott Yeudall
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA, United States of America
| | - Mitchell E. Granade
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Thurl E. Harris
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - J. David Castle
- Department of Cell Biology, University of Virginia, Charlottesville, VA, United States of America
| | - Norbert Leitinger
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Michelle L. Bland
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
- * E-mail:
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15
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O'Regan GC, Farag SH, Ostroff GR, Tabrizi SJ, Andre R. Wild-type huntingtin regulates human macrophage function. Sci Rep 2020; 10:17269. [PMID: 33057179 PMCID: PMC7560844 DOI: 10.1038/s41598-020-74042-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 09/17/2020] [Indexed: 01/07/2023] Open
Abstract
The huntingtin (HTT) protein in its mutant form is the cause of the inherited neurodegenerative disorder, Huntington's disease. Beyond its effects in the central nervous system, disease-associated mutant HTT causes aberrant phenotypes in myeloid-lineage innate immune system cells, namely monocytes and macrophages. Whether the wild-type form of the protein, however, has a role in normal human macrophage function has not been determined. Here, the effects of lowering the expression of wild-type (wt)HTT on the function of primary monocyte-derived macrophages from healthy, non-disease human subjects were examined. This demonstrated a previously undescribed role for wtHTT in maintaining normal macrophage health and function. Lowered wtHTT expression was associated, for instance, with a diminished release of induced cytokines, elevated phagocytosis and increased vulnerability to cellular stress. These may well occur by mechanisms different to that associated with the mutant form of the protein, given an absence of any effect on the intracellular signalling pathway predominantly associated with macrophage dysfunction in Huntington's disease.
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Affiliation(s)
- Grace C O'Regan
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Sahar H Farag
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Gary R Ostroff
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Two Biotech, Suite 113, Worcester, MA, 01605, USA
| | - Sarah J Tabrizi
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK. .,UK Dementia Research Institute at UCL, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
| | - Ralph Andre
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
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16
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Guo F, Qiu X, Zhu Y, Tan Z, Li Z, Ouyang D. Circulating choline is associated with coronary artery stenosis in patients with hypertension: A cross-sectional study of Chinese adults. J Clin Hypertens (Greenwich) 2020; 22:2069-2076. [PMID: 32966687 DOI: 10.1111/jch.14025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/10/2020] [Accepted: 08/13/2020] [Indexed: 01/08/2023]
Abstract
Choline is an important nutrient involved in multiple biosynthesis pathways. However, whether circulating choline levels are associated with the risk of hypertension (HTN) and artery stenosis in HTN remains unknown. We investigated the correlations of plasma choline with HTN and coronary artery injury and explored the utility of plasma choline as a diagnostic biomarker for HTN and artery stenosis. 193 HTN patients and 154 age- and sex-matched healthy controls (CON) were recruited in this study. Fasting plasma choline was detected using liquid chromatography tandem mass spectrometry. Choline levels were significantly higher in HTN without artery stenosis (HTN-AS) than CON (8.07 [7.19-9.24] μM vs 7.03 [6.21-8.13] μM, P < .01) group and were further upregulated in HTN with artery stenosis (HTN + AS) (8.63 [7.09-10.59] μM, P < .01) group. Patients with multivessel disease (MVD) also exhibited higher choline levels than those with single vessel disease (SVD) (8.64 [7.16-10.55] μM vs 8.04(6.74-9.38) μM, P < .01). Increased choline levels were independently associated with the risk of HTN (OR = 1.2, 95% CI: 1-1.45, P = .05), HTN + AS (OR = 1.27, 95% CI: 1.09-1.48, P < .01), and MVD (OR = 1.16, 95% CI: 1.02-1.31, P = .02) after adjustment for multiple risk factors. Receiver operating characteristic (ROC) analysis showed that choline had an area under curve (AUC) score of 0.69, 0.67, and 0.63 in determining HTN, HTN + AS, and MVD. In conclusion, higher choline levels were associated with increased risk of HTN and artery stenosis in hypertensive patients.
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Affiliation(s)
- Fei Guo
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Changsha, China.,Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha Duxact Biotech Co., Ltd, Changsha, China
| | - Xueting Qiu
- Department of Geriatric Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Yuanting Zhu
- Department of Geriatric Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Zhirong Tan
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Changsha, China
| | - Zhenyu Li
- Department of Geriatric Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Dongsheng Ouyang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Changsha, China.,Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha Duxact Biotech Co., Ltd, Changsha, China
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17
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ROS-associated immune response and metabolism: a mechanistic approach with implication of various diseases. Arch Toxicol 2020; 94:2293-2317. [PMID: 32524152 DOI: 10.1007/s00204-020-02801-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 06/02/2020] [Indexed: 12/14/2022]
Abstract
The immune system plays a pivotal role in maintaining the defense mechanism against external agents and also internal danger signals. Metabolic programming of immune cells is required for functioning of different subsets of immune cells under different physiological conditions. The field of immunometabolism has gained ground because of its immense importance in coordination and balance of immune responses. Metabolism is very much related with production of energy and certain by-products. Reactive oxygen species (ROS) are generated as one of the by-products of various metabolic pathways. The amount, localization of ROS and redox status determine transcription of genes, and also influences the metabolism of immune cells. This review discusses ROS, metabolism of immune cells at different cellular conditions and sheds some light on how ROS might regulate immunometabolism.
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18
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Jaroonwitchawan T, Visitchanakun P, Dang PC, Ritprajak P, Palaga T, Leelahavanichkul A. Dysregulation of Lipid Metabolism in Macrophages Is Responsible for Severe Endotoxin Tolerance in FcgRIIB-Deficient Lupus Mice. Front Immunol 2020; 11:959. [PMID: 32582149 PMCID: PMC7296175 DOI: 10.3389/fimmu.2020.00959] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022] Open
Abstract
FcgRIIB dysfunction is commonly found in patients with lupus, especially in Asia. LPS-tolerance is prominent in FcgRIIB–/– lupus mice. LPS-tolerant macrophages demonstrate cell energy depletion, which might affect lipid metabolism. Therefore, to explore lipid metabolism, LPS-tolerance was induced twice by LPS administration in macrophages and in mice. LPS-tolerant FcgRIIB–/– macrophages demonstrated lesser mitochondrial DNA (mtDNA), more severe ATP depletion, lower cytokine production, and higher lipid accumulation (oil red O staining) compared to LPS-tolerant WT cells. Mass-spectrometry-based lipidomic analysis demonstrated a higher abundance of phosphatidylethanolamine (PE) phospholipid in LPS-tolerant FcgRIIB–/– macrophages than WT cells. This was at least in part due to the lower expression of phosphatidylethanolamine N-methyltransferase (pemt), an enzyme that converts PE to phosphatidylcholine (PC). Aminoimidazole-4-carboxamide ribonucleotide (AICAR), a pemt inhibitor, worsens LPS-tolerance in WT macrophages and supports the impact of pemt upon LPS-tolerant FcgRIIB–/– macrophages. Additionally, phosphorylated AMP-activated protein kinase (AMPK-p), a molecule for ATP-restoration associated with pemt, and phosphorylated acetyl CoA carboxylase, a downstream signaling of AMPK-p, were higher in LPS-tolerant FcgRIIB–/– macrophages than WT. Furthermore, Compound C, an AMPK inhibitor, attenuated LPS-tolerance in both FcgRIIB–/– macrophages and mice. Taken together, the intense decrease in cytokine production after the second LPS stimulation (LPS-tolerance) in FcgRIIB–/– macrophages was possibly due to the impact of an immense cytokine synthesis after the first dose of LPS. This includes using up PEMT, an enzyme of phospholipid synthesis during cytokine production, and AMPK-p induction in response to profound ATP-depletion. Therefore, the manipulation of the AMPK/PEMT axis provides a novel therapeutic candidate for the treatment of severe LPS-tolerance in lupus.
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Affiliation(s)
| | - Peerapat Visitchanakun
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Phi Cong Dang
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Patcharee Ritprajak
- Department of Microbiology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Tanapat Palaga
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Asada Leelahavanichkul
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Translational Research in Inflammation and Immunology Research Unit (TRIRU), Department of Microbiology, Chulalongkorn University, Bangkok, Thailand
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19
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Petkevicius K, Virtue S, Bidault G, Jenkins B, Çubuk C, Morgantini C, Aouadi M, Dopazo J, Serlie MJ, Koulman A, Vidal-Puig A. Accelerated phosphatidylcholine turnover in macrophages promotes adipose tissue inflammation in obesity. eLife 2019; 8:e47990. [PMID: 31418690 PMCID: PMC6748830 DOI: 10.7554/elife.47990] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 08/15/2019] [Indexed: 12/28/2022] Open
Abstract
White adipose tissue (WAT) inflammation contributes to the development of insulin resistance in obesity. While the role of adipose tissue macrophage (ATM) pro-inflammatory signalling in the development of insulin resistance has been established, it is less clear how WAT inflammation is initiated. Here, we show that ATMs isolated from obese mice and humans exhibit markers of increased rate of de novo phosphatidylcholine (PC) biosynthesis. Macrophage-specific knockout of phosphocholine cytidylyltransferase A (CCTα), the rate-limiting enzyme of de novo PC biosynthesis pathway, alleviated obesity-induced WAT inflammation and insulin resistance. Mechanistically, CCTα-deficient macrophages showed reduced ER stress and inflammation in response to palmitate. Surprisingly, this was not due to lower exogenous palmitate incorporation into cellular PCs. Instead, CCTα-null macrophages had lower membrane PC turnover, leading to elevated membrane polyunsaturated fatty acid levels that negated the pro-inflammatory effects of palmitate. Our results reveal a causal link between obesity-associated increase in de novo PC synthesis, accelerated PC turnover and pro-inflammatory activation of ATMs.
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Affiliation(s)
- Kasparas Petkevicius
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
| | - Sam Virtue
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
| | - Guillaume Bidault
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
| | - Benjamin Jenkins
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
| | - Cankut Çubuk
- Clinical Bioinformatics AreaFundación Progreso y Salud, CDCA, Hospital Virgen del RocioSevillaSpain
- Functional Genomics NodeINB-ELIXIR-es, FPS, Hospital Virgen del RocioSevillaSpain
- Bioinformatics in Rare Diseases (BiER)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), FPS, Hospital Virgen del RocioSevillaSpain
| | - Cecilia Morgantini
- Department of Medicine, Integrated Cardio Metabolic CentreKarolinska InstitutetHuddingeSweden
| | - Myriam Aouadi
- Department of Medicine, Integrated Cardio Metabolic CentreKarolinska InstitutetHuddingeSweden
| | - Joaquin Dopazo
- Clinical Bioinformatics AreaFundación Progreso y Salud, CDCA, Hospital Virgen del RocioSevillaSpain
- Functional Genomics NodeINB-ELIXIR-es, FPS, Hospital Virgen del RocioSevillaSpain
- Bioinformatics in Rare Diseases (BiER)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), FPS, Hospital Virgen del RocioSevillaSpain
| | - Mireille J Serlie
- Department of Endocrinology and MetabolismAmsterdam University Medical CenterAmsterdamNetherlands
| | - Albert Koulman
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
| | - Antonio Vidal-Puig
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, MDU MRCCambridgeUnited Kingdom
- Wellcome Trust Sanger InstituteHinxtonUnited Kingdom
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20
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Sanchez-Lopez E, Zhong Z, Stubelius A, Sweeney SR, Booshehri LM, Antonucci L, Liu-Bryan R, Lodi A, Terkeltaub R, Lacal JC, Murphy AN, Hoffman HM, Tiziani S, Guma M, Karin M. Choline Uptake and Metabolism Modulate Macrophage IL-1β and IL-18 Production. Cell Metab 2019; 29:1350-1362.e7. [PMID: 30982734 PMCID: PMC6675591 DOI: 10.1016/j.cmet.2019.03.011] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 01/16/2019] [Accepted: 03/19/2019] [Indexed: 02/07/2023]
Abstract
Choline is a vitamin-like nutrient that is taken up via specific transporters and metabolized by choline kinase, which converts it to phosphocholine needed for de novo synthesis of phosphatidylcholine (PC), the main phospholipid of cellular membranes. We found that Toll-like receptor (TLR) activation enhances choline uptake by macrophages and microglia through induction of the choline transporter CTL1. Inhibition of CTL1 expression or choline phosphorylation attenuated NLRP3 inflammasome activation and IL-1β and IL-18 production in stimulated macrophages. Mechanistically, reduced choline uptake altered mitochondrial lipid profile, attenuated mitochondrial ATP synthesis, and activated the energy sensor AMP-activated protein kinase (AMPK). By potentiating mitochondrial recruitment of DRP1, AMPK stimulates mitophagy, which contributes to termination of NLRP3 inflammasome activation. Correspondingly, choline kinase inhibitors ameliorated acute and chronic models of IL-1β-dependent inflammation.
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Affiliation(s)
- Elsa Sanchez-Lopez
- Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, 92037, USA
| | - Zhenyu Zhong
- Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, 92037, USA; Department of Immunology, University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd, Dallas TX 75390, USA
| | - Alexandra Stubelius
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, CA, 92037, USA
| | - Shannon R Sweeney
- Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX, 78723-3092, USA
| | - Laela M Booshehri
- Department of Pediatrics and Rady Children's Hospital, University of California San Diego, La Jolla, CA, 92037, USA
| | - Laura Antonucci
- Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, 92037, USA
| | - Ru Liu-Bryan
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, CA, 92037, USA; VA San Diego Healthcare System, University of California San Diego, La Jolla, CA, 92037, USA
| | - Alessia Lodi
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX, 78723-3092, USA; Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX, 78723-3092, USA
| | - Robert Terkeltaub
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, CA, 92037, USA; VA San Diego Healthcare System, University of California San Diego, La Jolla, CA, 92037, USA
| | - Juan Carlos Lacal
- Translational Oncology, Department of Oncology, Hospital Universitario Fuenlabrada, Instituto de Investigación Sanitaria IdiPAZ, Madrid, Spain
| | - Anne N Murphy
- Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, 92037, USA
| | - Hal M Hoffman
- Department of Pediatrics and Rady Children's Hospital, University of California San Diego, La Jolla, CA, 92037, USA
| | - Stefano Tiziani
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX, 78723-3092, USA; Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX, 78723-3092, USA; Department of Pediatrics, Dell Medical School, The University of Texas at Austin, Austin, TX, 78723-3092, USA
| | - Monica Guma
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, CA, 92037, USA
| | - Michael Karin
- Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, 92037, USA.
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21
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Cavallini C, Zannini C, Olivi E, Tassinari R, Taglioli V, Rossi M, Poggi P, Chatgilialoglu A, Simonazzi G, Alviano F, Bonsi L, Ventura C. Restoring In Vivo-Like Membrane Lipidomics Promotes Exosome Trophic Behavior from Human Placental Mesenchymal Stromal/Stem Cells. Cell Transplant 2019; 27:55-69. [PMID: 29562775 PMCID: PMC6434476 DOI: 10.1177/0963689717723016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Human mesenchymal stem cells (hMSCs) are an effective tool in regenerative medicine notably for their intrinsic plentiful paracrine activity rather than differentiating properties. The hMSC secretome includes a wide spectrum of regulatory and trophic factors, encompassing several naked molecules as well as different kinds of extracellular vesicles (EVs). Among EVs, exosomes represent an intriguing population, able to shuttle proteins, transcription factors, and genetic materials, with a relevant role in cell-to-cell communication, modulating biological responses in recipient cells. In this context, the extracellular milieu can greatly impact the paracrine activity of stem cells, modifying their metabolism, and the dynamics of vesicle secretion. In the present study, we investigated the effects elicited on exosome patterning by tailored, ad hoc formulated lipid supplementation (Refeed®) in MSCs derived from human fetal membranes (hFM-MSCs). Wound healing experiments revealed that stem cell exposure to exosomes obtained from Refeed®-supplemented hFM-MSCs increased their migratory capability, although the amount of exosomes released after Refeed® supplementation was lower than that yielded from non-supplemented cells. We found that such a decrease was mainly due to a different rate of exosomal exocytosis rather than to an effect of the lipid supplement on the endocytic pathway. Endoplasmic reticulum homeostasis was modified by supplementation, through the upregulation of PKR-like ER kinase (PERK) and inositol-requiring enzyme 1α (IRE1α). Increased expression of these proteins did not lead to stress-induced, unfolded protein response (UPR)-mediated apoptosis, nor did it affect phosphorylation of p38 kinase, suggesting that PERK and IRE1α overexpression was due to augmented metabolic activities mediated by optimization of a cellular feeding network afforded through lipid supplementation. In summary, these results demonstrate how tailored lipid supplementation can successfully modify the paracrine features in hFM-MSCs, impacting both intracellular vesicle trafficking and secreted exosome number and function.
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Affiliation(s)
- Claudia Cavallini
- 1 GUNA - ATTRE (Advanced Therapies and Tissue Regeneration), Innovation Accelerator at CNR, Via Gobetti 101, 40129 Bologna, Italy.,2 National Institute of Biostructures and Biosystems (NIBB), Rome, Italy.,3 Ettore Sansavini Health Science Foundation ONLUS-Lab SWITH, Lugo, Italy
| | - Chiara Zannini
- 3 Ettore Sansavini Health Science Foundation ONLUS-Lab SWITH, Lugo, Italy.,4 Department of Experimental, Diagnostic and Specialty Medicine, Unit of Nephrology, Dialysis and Renal Transplant, St. Orsola-Malpighi University Hospital, Bologna, Italy
| | - Elena Olivi
- 1 GUNA - ATTRE (Advanced Therapies and Tissue Regeneration), Innovation Accelerator at CNR, Via Gobetti 101, 40129 Bologna, Italy.,2 National Institute of Biostructures and Biosystems (NIBB), Rome, Italy.,3 Ettore Sansavini Health Science Foundation ONLUS-Lab SWITH, Lugo, Italy
| | - Riccardo Tassinari
- 1 GUNA - ATTRE (Advanced Therapies and Tissue Regeneration), Innovation Accelerator at CNR, Via Gobetti 101, 40129 Bologna, Italy.,2 National Institute of Biostructures and Biosystems (NIBB), Rome, Italy.,3 Ettore Sansavini Health Science Foundation ONLUS-Lab SWITH, Lugo, Italy
| | - Valentina Taglioli
- 2 National Institute of Biostructures and Biosystems (NIBB), Rome, Italy.,6 Department of Experimental, Diagnostic and Specialty Medicine, Laboratory of Experimental Cardiology, St. Orsola-Malpighi University Hospital, Bologna, Italy
| | - Martina Rossi
- 5 Department of Experimental, Diagnostic and Specialty Medicine, Unit of Histology, Embryology and Applied Biology, University of Bologna, Bologna, Italy
| | | | | | - Giuliana Simonazzi
- 8 Division of Obstetrics and Prenatal Medicine, Department of Medical and Surgical Sciences, St. Orsola-Malpighi University Hospital, Bologna, Italy
| | - Francesco Alviano
- 5 Department of Experimental, Diagnostic and Specialty Medicine, Unit of Histology, Embryology and Applied Biology, University of Bologna, Bologna, Italy
| | - Laura Bonsi
- 5 Department of Experimental, Diagnostic and Specialty Medicine, Unit of Histology, Embryology and Applied Biology, University of Bologna, Bologna, Italy
| | - Carlo Ventura
- 1 GUNA - ATTRE (Advanced Therapies and Tissue Regeneration), Innovation Accelerator at CNR, Via Gobetti 101, 40129 Bologna, Italy.,2 National Institute of Biostructures and Biosystems (NIBB), Rome, Italy.,9 CNR, Institute of Organic Synthesis and Photoreactivity (Istituto per la Sintesi Organica e la Fotoreattività ISOF), Via Gobetti 101, 40129 Bologna, Italy
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22
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Liu M, O'Connor RS, Trefely S, Graham K, Snyder NW, Beatty GL. Metabolic rewiring of macrophages by CpG potentiates clearance of cancer cells and overcomes tumor-expressed CD47-mediated 'don't-eat-me' signal. Nat Immunol 2019; 20:265-275. [PMID: 30664738 PMCID: PMC6380920 DOI: 10.1038/s41590-018-0292-y] [Citation(s) in RCA: 168] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/01/2018] [Indexed: 12/12/2022]
Abstract
Macrophages enforce anti-tumor immunity by engulfing and killing tumor cells. Although these functions are determined by a balance of stimulatory and inhibitory signals, the role of macrophage metabolism is unknown. Here, we study the capacity of macrophages to circumvent inhibitory activity mediated by CD47 on cancer cells. We show that stimulation with CpG, a TLR9 agonist, evokes changes in the central carbon metabolism of macrophages that enable anti-tumor activity, including engulfment of CD47+ cancer cells. CpG activation engenders a metabolic state, that requires fatty acid oxidation and shunting of tricarboxylic acid cycle intermediates for de novo lipid biosynthesis. This integration of metabolic inputs is underpinned by carnitine palmitoyltransferase 1A and ATP citrate lyase, which together, impart macrophages with anti-tumor potential capable of overcoming inhibitory CD47 on cancer cells. Our findings identify central carbon metabolism to be a novel determinant and potential therapeutic target for stimulating anti-tumor activity by macrophages.
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Affiliation(s)
- Mingen Liu
- Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Roddy S O'Connor
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sophie Trefely
- AJ Drexel Autism Institute, Drexel University, Philadelphia, PA, USA.,Department of Cancer Biology, Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Kathleen Graham
- Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Gregory L Beatty
- Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA, USA. .,Division of Hematology-Oncology, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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23
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Glycerol-3-phosphate acyltransferases 3 and 4 direct glycerolipid synthesis and affect functionality in activated macrophages. Biochem J 2019; 476:85-99. [DOI: 10.1042/bcj20180381] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 12/03/2018] [Accepted: 12/05/2018] [Indexed: 12/13/2022]
Abstract
AbstractMacrophage classical M1 activation via TLR4 triggers a variety of responses to achieve the elimination of foreign pathogens. During this process, there is also an increase in lipid droplets which contain large quantities of triacylglycerol (TAG) and phospholipid (PL). The functional consequences of this increment in lipid mass are poorly understood. Here, we studied the contribution of glycerolipid synthesis to lipid accumulation, focusing specifically on the first and rate-limiting enzyme of the pathway: glycerol-3-phosphate acyltransferase (GPAT). Using bone marrow-derived macrophages (BMDMs) treated with Kdo2-lipid A, we showed that glycerolipid synthesis is induced during macrophage activation. GPAT4 protein level and GPAT3/GPAT4 enzymatic activity increase during this process, and these two isoforms were required for the accumulation of cell TAG and PL. The phagocytic capacity of Gpat3−/− and Gpat4−/− BMDM was impaired. Additionally, inhibiting fatty acid β-oxidation reduced phagocytosis only partially, suggesting that lipid accumulation is not necessary for the energy requirements for phagocytosis. Finally, Gpat4−/− BMDM expressed and released more pro-inflammatory cytokines and chemokines after macrophage activation, suggesting a role for GPAT4 in suppressing inflammatory responses. Together, these results provide evidence that glycerolipid synthesis directed by GPAT4 is important for the attenuation of the inflammatory response in activated macrophages.
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24
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Cornell RB, Taneva SG, Dennis MK, Tse R, Dhillon RK, Lee J. Disease-linked mutations in the phosphatidylcholine regulatory enzyme CCTα impair enzymatic activity and fold stability. J Biol Chem 2018; 294:1490-1501. [PMID: 30559292 DOI: 10.1074/jbc.ra118.006457] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/05/2018] [Indexed: 11/06/2022] Open
Abstract
CTP:phosphocholine cytidylyltransferase (CCT) is the key regulatory enzyme in phosphatidylcholine (PC) synthesis and is activated by binding to PC-deficient membranes. Mutations in the gene encoding CCTα (PCYT1A) cause three distinct pathologies in humans: lipodystrophy, spondylometaphyseal dysplasia with cone-rod dystrophy (SMD-CRD), and isolated retinal dystrophy. Previous analyses showed that for some disease-linked PCYT1A variants steady state levels of CCTα and PC synthesis were reduced in patient fibroblasts, but other variants impaired PC synthesis with little effect on CCT levels. To explore the impact on CCT stability and function we expressed WT and mutant CCTs in COS-1 cells, which have very low endogenous CCT. Over-expression of two missense variants in the catalytic domain (V142M and P150A) generated aggregated enzymes that could not be refolded after solubilization by denaturation. Other mutations in the catalytic core that generated CCTs with reduced solubility could be purified. Five variants destabilized the catalytic domain-fold as assessed by lower transition temperatures for unfolding, and three of these manifested defects in substrate Km values. A mutation (R223S) in a signal-transducing linker between the catalytic and membrane-binding domains also impaired enzyme kinetics. E280del, a single amino acid deletion in the autoinhibitory helix increased the constitutive (lipid-independent) enzyme activity ∼4-fold. This helix also participates in membrane binding, and surprisingly E280del enhanced the enzyme's response to anionic lipid vesicles ∼4-fold. These in vitro analyses on purified mutant CCTs will complement future measurements of their impact on PC synthesis in cultured cells and in tissues with a stringent requirement for CCTα.
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Affiliation(s)
- Rosemary B Cornell
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada; Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada.
| | - Svetla G Taneva
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
| | - Melissa K Dennis
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
| | - Ronnie Tse
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
| | - Randeep K Dhillon
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
| | - Jaeyong Lee
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
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25
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Garcia M, Mamedova LK, Barton B, Bradford BJ. Choline Regulates the Function of Bovine Immune Cells and Alters the mRNA Abundance of Enzymes and Receptors Involved in Its Metabolism in vitro. Front Immunol 2018; 9:2448. [PMID: 30410489 PMCID: PMC6211314 DOI: 10.3389/fimmu.2018.02448] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 10/03/2018] [Indexed: 12/16/2022] Open
Abstract
Dietary choline can impact systemic immunity, but it remains unclear whether this is primarily via direct impacts on immune cells or secondary effects of altered metabolic function. To determine whether increased choline concentrations (3.2, 8.2, 13.2 μM) in cell culture alter the function of bovine innate and adaptive immune cells, we isolated cells from dairy cows in early and mid-lactation as models of immuno-compromised and competent cells, respectively. Phagocytic and killing capacity of isolated neutrophils were linearly diminished with increasing doses of choline. In contrast, lymphocyte proliferation was linearly enhanced with increasing doses of choline. Furthermore, increasing doses of choline increased the mRNA abundance of genes involved in the synthesis of choline products (betaine, phosphatidylcholine, and acetylcholine) as well as muscarinic and nicotinic acetylcholine receptors in a quadratic and linear fashion for neutrophils and monocytes, respectively. Phagocytic and killing capacity of neutrophils and proliferation of lymphocytes were not affected by stage of lactation or its interaction with choline or LPS. In neutrophils from early lactation cows, choline linearly increased the mRNA abundance of muscarinic and nicotinic cholinergic receptors, whereas choline-supplemented monocytes from mid-lactation cows linearly increased the mRNA abundance of several genes coding for choline metabolism enzymes. These data demonstrate that choline regulates the inflammatory response of immune cells and suggest that the mechanism may involve one or more of its metabolic products.
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Affiliation(s)
- Miriam Garcia
- Department of Animal Sciences and Industry, Kansas State University, Manhattan, KS, United States
| | - Laman K Mamedova
- Department of Animal Sciences and Industry, Kansas State University, Manhattan, KS, United States
| | | | - Barry J Bradford
- Department of Animal Sciences and Industry, Kansas State University, Manhattan, KS, United States
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26
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Snider SA, Margison KD, Ghorbani P, LeBlond ND, O'Dwyer C, Nunes JRC, Nguyen T, Xu H, Bennett SAL, Fullerton MD. Choline transport links macrophage phospholipid metabolism and inflammation. J Biol Chem 2018; 293:11600-11611. [PMID: 29880645 DOI: 10.1074/jbc.ra118.003180] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/29/2018] [Indexed: 12/21/2022] Open
Abstract
Choline is an essential nutrient that is required for synthesis of the main eukaryote phospholipid, phosphatidylcholine. Macrophages are innate immune cells that survey and respond to danger and damage signals. Although it is well-known that energy metabolism can dictate macrophage function, little is known as to the importance of choline homeostasis in macrophage biology. We hypothesized that the uptake and metabolism of choline are important for macrophage inflammation. Polarization of primary bone marrow macrophages with lipopolysaccharide (LPS) resulted in an increased rate of choline uptake and higher levels of PC synthesis. This was attributed to a substantial increase in the transcript and protein expression of the choline transporter-like protein-1 (CTL1) in polarized cells. We next sought to determine the importance of choline uptake and CTL1 for macrophage immune responsiveness. Chronic pharmacological or CTL1 antibody-mediated inhibition of choline uptake resulted in altered cytokine secretion in response to LPS, which was associated with increased levels of diacylglycerol and activation of protein kinase C. These experiments establish a previously unappreciated link between choline phospholipid metabolism and macrophage immune responsiveness, highlighting a critical and regulatory role for macrophage choline uptake via the CTL1 transporter.
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Affiliation(s)
- Shayne A Snider
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Kaitlyn D Margison
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Peyman Ghorbani
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Nicholas D LeBlond
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Conor O'Dwyer
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Julia R C Nunes
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Thao Nguyen
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; the Ottawa Institute of Systems Biology and University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Hongbin Xu
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; the Ottawa Institute of Systems Biology and University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Steffany A L Bennett
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; the Ottawa Institute of Systems Biology and University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Morgan D Fullerton
- University of Ottawa Centre for Infection, Immunity, and Inflammation and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.
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Cui S, Li K, Ang L, Liu J, Cui L, Song X, Lv S, Mahmud E. Plasma Phospholipids and Sphingolipids Identify Stent Restenosis After Percutaneous Coronary Intervention. JACC Cardiovasc Interv 2017. [DOI: 10.1016/j.jcin.2017.04.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Dellschaft NS, Richard C, Lewis ED, Goruk S, Jacobs RL, Curtis JM, Field CJ. The dietary form of choline during lactation affects maternal immune function in rats. Eur J Nutr 2017; 57:2189-2199. [PMID: 28667457 DOI: 10.1007/s00394-017-1493-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 06/25/2017] [Indexed: 12/11/2022]
Abstract
PURPOSE The present study was designed to determine the effects of both choline form and availability on maternal immune function during lactation. METHODS Sprague-Dawley rats were randomized to one of the three diets 24-48 h before parturition and fed ad libitum until 21 days postnatal: 1 g/kg choline as free choline (C, n = 11), the current form, and amount of choline in commercial diets; 1 g/kg choline as phosphatidylcholine (PC1, n = 11); or 2.5 g/kg choline as PC (PC2.5, n = 8). Choline metabolites in offspring stomach contents were quantified. At 21 days, lymphocytes from mothers' mesenteric lymph nodes and spleens were isolated and phenotypes and ex vivo cytokine production after mitogen exposure were determined. RESULTS There was a higher proportion of choline and a lower proportion of lyso-PC in stomach contents (representing dam's milk) of C pups compared to PC1. In the mesenteric lymph nodes, feeding PC1 compared to C led to a higher IL-2 production after Concanavalin A (ConA) stimulation and a higher proportion of T cells (CD3+) and a lower proportion of B cells [immunoglobulin (Ig)κ, CD45RA+, and IgM+; P < 0.05]. Splenocytes from the PC1 group produced more IL-6 and TNF-α after lipopolysaccharides stimulation compared to C (P < 0.05). Splenocytes from the PC2.5 group produced more IL-2 and IL-6 after ConA stimulation compared to PC1 (P < 0.05). CONCLUSIONS Feeding choline as PC in the maternal diet improved the ability of immune cells to respond ex vivo to mitogens and increasing the amount of PC in the diet further improved T cell proliferation.
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Affiliation(s)
- N S Dellschaft
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
- Early Life Research Unit, Academic Division of Child Health, Obstetrics and Gynaecology, School of Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - C Richard
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
| | - E D Lewis
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
| | - S Goruk
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
| | - R L Jacobs
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
| | - J M Curtis
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada
| | - C J Field
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-126A Li Ka Shing Centre for Health Research Innovation, Edmonton, AB, T6G 2E1, Canada.
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Feeding a diet devoid of choline to lactating rodents restricts growth and lymphocyte development in offspring. Br J Nutr 2016; 116:1001-12. [PMID: 27480608 DOI: 10.1017/s0007114516002919] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The nutrient choline is necessary for membrane synthesis and methyl donation, with increased requirements during lactation. The majority of immune development occurs postnatally, but the importance of choline supply for immune development during this critical period is unknown. The objective of this study was to determine the importance of maternal supply of choline during suckling on immune function in their offspring among rodents. At parturition, Sprague-Dawley dams were randomised to either a choline-devoid (ChD; n 7) or choline-sufficient (ChS, 1 g/kg choline; n 10) diet with their offspring euthanised at 3 weeks of age. In a second experiment, offspring were weaned to a ChS diet until 10 weeks of age (ChD-ChS, n 5 and ChS-ChS, n 9). Splenocytes were isolated, and parameters of immune function were measured. The ChD offspring received less choline in breast milk and had lower final body and organ weight compared with ChS offspring (P<0·05), but this effect disappeared by week 10 with choline supplementation from weaning. ChD offspring had a higher proportion of T cells expressing activation markers (CD71 or CD28) and a lower proportion of total B cells (CD45RA+) and responded less to T cell stimulation (lower stimulation index and less IFN-γ production) ex vivo (P<0·05). ChD-ChS offspring had a lower proportion of total and activated CD4+ T cells, and produced less IL-6 after mitogen stimulation compared with cells from ChS-ChS (P<0·05). Our study suggests that choline is required in the suckling diet to facilitate immune development, and choline deprivation during this critical period has lasting effects on T cell function later in life.
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Lewis ED, Richard C, Goruk S, Dellschaft NS, Curtis JM, Jacobs RL, Field CJ. The Form of Choline in the Maternal Diet Affects Immune Development in Suckled Rat Offspring. J Nutr 2016; 146:823-30. [PMID: 26936140 DOI: 10.3945/jn.115.225888] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/14/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Lipid-soluble phosphatidylcholine (PC) and aqueous free choline are absorbed and metabolized differently, but the metabolic effects of feeding these 2 forms of choline have not been thoroughly investigated. OBJECTIVE We sought to compare the effects of PC and free choline in the maternal diet on the development of the offspring's immune system. METHODS During lactation, Sprague-Dawley dams (n= 10) were randomly assigned to 1 of 2 diet groups containing the same concentration of total choline (1 g/kg diet) as free choline (choline bitartrate) or PC (egg lecithin). The splenocytes of pups aged 21 d were isolated and stimulated ex vivo with concanavalin A (ConA) or lipopolysaccharide (LPS), and the choline concentrations of stomach content, plasma, and the spleen were measured. RESULTS Pups from PC-fed dams had a lower proportion of cells involved in antigen presentation but produced 54% more interleukin (IL)-2, 163% more IL-6, and 107% more IFN-γ after ConA stimulation and 110% more IL-6 and 43% more tumor necrosis factor (TNF)-α after LPS stimulation (allP< 0.05). The PC concentrations were significantly higher in the plasma and spleen of pups from PC-fed dams (P< 0.05). Increasing the supply of PC in the form of lysophosphatidylcholine to splenocytes in vitro increased the rate of proliferation and IL-2 production and the surface expression of CD25, CD28, CD71, and CD152 on CD8+ T cells, suggesting 1 possible mechanism. CONCLUSIONS The results of this study demonstrate that providing choline to rats in the form of PC (compared to free choline), possibly by increasing the supply of PC to the suckling pups, promotes maturation and improves function of the offspring's immune system.
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Affiliation(s)
- Erin D Lewis
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
| | - Caroline Richard
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
| | - Susan Goruk
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
| | - Neele S Dellschaft
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and Early Life Research Unit, Academic Division of Child Health, Obstetrics and Gynaecology, School of Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Jonathan M Curtis
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
| | - René L Jacobs
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
| | - Catherine J Field
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, Canada; and
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Köberlin MS, Heinz LX, Superti-Furga G. Functional crosstalk between membrane lipids and TLR biology. Curr Opin Cell Biol 2016; 39:28-36. [PMID: 26895312 DOI: 10.1016/j.ceb.2016.01.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 01/20/2016] [Accepted: 01/27/2016] [Indexed: 12/16/2022]
Abstract
Toll-like receptors (TLRs) are important transmembrane proteins of the innate immune system that detect invading pathogens and subsequently orchestrate an immune response. The ensuing inflammatory processes are connected to lipid metabolism at multiple levels. Here, we describe different aspects of how membrane lipids can shape the response of TLRs. Recent reports have uncovered the role of individual lipid species on membrane protein function and mouse models have contributed to the understanding of how changes in lipid metabolism alter TLR signaling, endocytosis, and cytokine secretion. Finally, we discuss the importance of systematic approaches to identify the function of individual lipid species or the composition of membrane lipids in TLR-related processes.
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Affiliation(s)
- Marielle S Köberlin
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Leonhard X Heinz
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Giulio Superti-Furga
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria; Center for Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria.
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Membrane lipid compositional sensing by the inducible amphipathic helix of CCT. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1861:847-861. [PMID: 26747646 DOI: 10.1016/j.bbalip.2015.12.022] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/22/2015] [Accepted: 12/29/2015] [Indexed: 11/21/2022]
Abstract
The amphipathic helical (AH) membrane binding motif is recognized as a major device for lipid compositional sensing. We explore the function and mechanism of sensing by the lipid biosynthetic enzyme, CTP:phosphocholine cytidylyltransferase (CCT). As the regulatory enzyme in phosphatidylcholine (PC) synthesis, CCT contributes to membrane PC homeostasis. CCT directly binds and inserts into the surface of bilayers that are deficient in PC and therefore enriched in lipids that enhance surface charge and/or create lipid packing voids. These two membrane physical properties induce the folding of the CCT M domain into a ≥60 residue AH. Membrane binding activates catalysis by a mechanism that has been partially deciphered. We review the evidence for CCT compositional sensing, and the membrane and protein determinants for lipid selective membrane-interactions. We consider the factors that promote the binding of CCT isoforms to the membranes of the ER, nuclear envelope, or lipid droplets, but exclude CCT from other organelles and the plasma membrane. The CCT sensing mechanism is compared with several other proteins that use an AH motif for membrane compositional sensing. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon.
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Cornell RB, Ridgway ND. CTP:phosphocholine cytidylyltransferase: Function, regulation, and structure of an amphitropic enzyme required for membrane biogenesis. Prog Lipid Res 2015; 59:147-71. [PMID: 26165797 DOI: 10.1016/j.plipres.2015.07.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 07/07/2015] [Accepted: 07/07/2015] [Indexed: 12/12/2022]
Abstract
CTP:phosphocholine cytidylyltransferase (CCT) catalyzes a rate-limiting and regulated step in the CDP-choline pathway for the synthesis of phosphatidylcholine (PC) and PC-derived lipids. Control of CCT activity is multi-layered, and includes direct regulation by reversible membrane binding involving a built-in lipid compositional sensor. Thus CCT contributes to phospholipid compositional homeostasis. CCT also modifies the curvature of its target membrane. Knowledge of CCT structure and regulation of its catalytic function are relatively advanced compared to many lipid metabolic enzymes, and are reviewed in detail. Recently the genetic origins of two human developmental and lipogenesis disorders have been traced to mutations in the gene for CCTα.
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Affiliation(s)
- Rosemary B Cornell
- Department of Molecular Biology and Biochemistry and the Department of Chemistry, Simon Fraser University, Burnaby, B.C. V5A-1S6, Canada.
| | - Neale D Ridgway
- Departments of Pediatrics, and Biochemistry and Molecular Biology, Atlantic Research Centre, Dalhousie University, Halifax, Nova Scotia B3H-4H7, Canada
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Abstract
Choline demands during lactation are high; however, detailed knowledge is lacking regarding the optimal dietary intake during this critical period. The present study was designed to determine the effects of varying intakes of choline on maternal immune function during lactation. Primiparous Sprague–Dawley rats (n42) were randomised 24-48 h before birth and fed the following diets for 21 d: choline-devoid (0 g choline/kg diet; D,n10); 1·0 g choline/kg diet (C1,n11); 2·5 g choline/kg diet (C2·5,n10); 6·2 g choline/kg diet (C6,n11). Splenocytes were isolated and stimulatedex vivowith concanavalin A, lipopolysaccharide (LPS) or CD3/CD28. D and C6 dams had lower final body weight, spleen weight and average pup weight than C1 dams (P< 0·05). There was a linear relationship between free choline concentration in pup stomach contents with maternal dietary choline content (P< 0·001,r20·415). Compared with C1 and C2·5, D spleens had a lower proportion of mature T cells and activated suppressor cells, and this resulted in reduced cytokine production after stimulation (P< 0·05). Feeding 6·2 g choline/kg diet resulted in a higher cytokine production after stimulation with CD3/CD28 (P< 0·05). Except for a higher IL-6 production after LPS stimulation with cells from the C2·5 dams (P< 0·05), there were no differences between the C1 and C2·5 dams. For the first time, we show that feeding lactating mothers a diet free of choline has substantial effects on their immune function and on offspring growth. Additionally, excess dietary choline had adverse effects on maternal and offspring body weight but only minimal effects on maternal immune function.
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35
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Zhang J, Li C, Tang X, Lu Q, Sa R, Zhang H. Proteome changes in the small intestinal mucosa of broilers (Gallus gallus) induced by high concentrations of atmospheric ammonia. Proteome Sci 2015; 13:9. [PMID: 25741220 PMCID: PMC4347970 DOI: 10.1186/s12953-015-0067-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 02/11/2015] [Indexed: 01/15/2023] Open
Abstract
Background Ammonia is a well-known toxicant both existing in atmospheric and aquatic system. So far, most studies of ammonia toxicity focused on mammals or aquatic animals. With the development of poultry industry, ammonia as a main source of contaminant in the air is causing more and more problems on broiler production, especially lower growth rate. The molecular mechanisms that underlie the negative effects of ammonia on the growth and intestine of broilers are yet unclear. We investigated the growth, gut morphology, and mucosal proteome of Arbor Acres broilers (Gallus gallus) exposed to high concentrations of atmospheric ammonia by performing a proteomics approach integrated with traditional methods. Results Exposure to ammonia interfered with the development of immune organ and gut villi. Meanwhile, it greatly reduced daily weight gain and feed intake, and enhanced feed conversion ratio. A total of 43 intestinal mucosal proteins were found to be differentially abundant. Up-regulated proteins are related to oxidative phosphorylation and apoptosis. Down-regulated proteins are related to cell structure and growth, transcriptional and translational regulation, immune response, oxidative stress and nutrient metabolism. These results indicated that exposure to ammonia triggered oxidative stress, and interfered with nutrient absorption and immune function in the small intestinal mucosa of broilers. Conclusions These findings have important implications for understanding the toxic mechanisms of ammonia on intestine of broilers, which provides new information that can be used for intervention using nutritional strategies in the future. Electronic supplementary material The online version of this article (doi:10.1186/s12953-015-0067-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jize Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
| | - Cong Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
| | - Xiangfang Tang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
| | - Qingping Lu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
| | - Renna Sa
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
| | - Hongfu Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193 People's Republic of China
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Murray RZ, Stow JL. Cytokine Secretion in Macrophages: SNAREs, Rabs, and Membrane Trafficking. Front Immunol 2014; 5:538. [PMID: 25386181 PMCID: PMC4209870 DOI: 10.3389/fimmu.2014.00538] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 10/10/2014] [Indexed: 12/21/2022] Open
Abstract
Macrophages have the capacity to rapidly secrete a wide range of inflammatory mediators that influence the development and extent of an inflammatory response. Newly synthesized and/or preformed stored cytokines and other inflammatory mediators are released upon stimulation, the timing, and volume of which is highly regulated. To finely tune this process, secretion is regulated at many levels; at the level of transcription and translation and post-translationally at the endoplasmic reticulum (ER), Golgi, and at or near the cell surface. Here, we discuss recent advances in deciphering these cytokine pathways in macrophages, focusing on recent discoveries regarding the cellular machinery and mechanisms implicated in the synthesis, trafficking, and secretion of cytokines. The specific roles of trafficking machinery including chaperones, GTPases, cytoskeletal proteins, and SNARE membrane fusion proteins will be discussed.
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Affiliation(s)
- Rachael Zoe Murray
- Institute of Health and Biomedical Innovation, Queensland University of Technology , Brisbane, QLD , Australia
| | - Jennifer Lea Stow
- Institute for Molecular Bioscience, The University of Queensland , Brisbane, QLD , Australia
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Ridgway ND. The role of phosphatidylcholine and choline metabolites to cell proliferation and survival. Crit Rev Biochem Mol Biol 2013; 48:20-38. [PMID: 23350810 DOI: 10.3109/10409238.2012.735643] [Citation(s) in RCA: 206] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The reorganization of metabolic pathways in cancer facilitates the flux of carbon and reducing equivalents into anabolic pathways at the expense of oxidative phosphorylation. This provides rapidly dividing cells with the necessary precursors for membrane, protein and nucleic acid synthesis. A fundamental metabolic perturbation in cancer is the enhanced synthesis of fatty acids by channeling glucose and/or glutamine into cytosolic acetyl-CoA and upregulation of key biosynthetic genes. This lipogenic phenotype also extends to the production of complex lipids involved in membrane synthesis and lipid-based signaling. Cancer cells display sensitivity to ablation of fatty acid synthesis possibly as a result of diminished capacity to synthesize complex lipids involved in signaling or growth pathways. Evidence has accrued that phosphatidylcholine, the major phospholipid component of eukaryotic membranes, as well as choline metabolites derived from its synthesis and catabolism, contribute to both proliferative growth and programmed cell death. This review will detail our current understanding of how coordinated changes in substrate availability, gene expression and enzyme activity lead to altered phosphatidylcholine synthesis in cancer, and how these changes contribute directly or indirectly to malignant growth. Conversely, apoptosis targets key steps in phosphatidylcholine synthesis and degradation that are linked to disruption of cell cycle regulation, reinforcing the central role that phosphatidylcholine and its metabolites in determining cell fate.
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Affiliation(s)
- Neale D Ridgway
- Departments of Pediatrics and Biochemistry & Molecular Biology, The Atlantic Research Centre, Dalhousie University, Halifax, Nova Scotia Canada.
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38
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Stow JL, Murray RZ. Intracellular trafficking and secretion of inflammatory cytokines. Cytokine Growth Factor Rev 2013; 24:227-39. [PMID: 23647915 DOI: 10.1016/j.cytogfr.2013.04.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The secretion of cytokines by immune cells plays a significant role in determining the course of an inflammatory response. The levels and timing of each cytokine released are critical for mounting an effective but confined response, whereas excessive or dysregulated inflammation contributes to many diseases. Cytokines are both culprits and targets for effective treatments in some diseases. The multiple points and mechanisms that have evolved for cellular control of cytokine secretion highlight the potency of these mediators and the fine tuning required to manage inflammation. Cytokine production in cells is regulated by cell signaling, and at mRNA and protein synthesis levels. Thereafter, the intracellular transport pathways and molecular trafficking machinery have intricate and essential roles in dictating the release and activity of cytokines. The trafficking machinery and secretory (exocytic) pathways are complex and highly regulated in many cells, involving specialized membranes, molecules and organelles that enable these cells to deliver cytokines to often-distinct areas of the cell surface, in a timely manner. This review provides an overview of secretory pathways - both conventional and unconventional - and key families of trafficking machinery. The prevailing knowledge about the trafficking and secretion of a number of individual cytokines is also summarized. In conclusion, we present emerging concepts about the functional plasticity of secretory pathways and their modulation for controlling cytokines and inflammation.
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Affiliation(s)
- Jennifer L Stow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia.
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Proprotein convertase 1/3 (PC1/3) in the rat alveolar macrophage cell line NR8383: localization, trafficking and effects on cytokine secretion. PLoS One 2013; 8:e61557. [PMID: 23637853 PMCID: PMC3634814 DOI: 10.1371/journal.pone.0061557] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 03/11/2013] [Indexed: 12/20/2022] Open
Abstract
The proprotein convertase 1/3 (PC1/3) is an important post-translational processing enzyme for the activation of precursor proteins within the regulated secretory pathway. Well characterized for its role in the neural and endocrine systems, we recently reported an unconventional role of PC1/3 as a modulator of the Toll-like receptor innate immune response. There are only a few reports that have studied PC1/3 expression in macrophages, and more investigation is needed to better characterize its function. These studies would greatly benefit from model cell lines. Our study aims to identify and characterize PC1/3 in a relevant model macrophage cell line and to determine the links between PC1/3 and innate immune cellular responses. We describe the rat alveolar cell line, NR8383, as expressing PC1/3 and the most common Toll-like receptors. In NR8383 cells, PC1/3 is localized at the Trans-Golgi network and traffics to lysosome related vesicles upon lipopolysaccharide stimulation. Moreover, we report the co-localization of PC1/3 and Toll-like receptor 4 upon lipopolysaccharide stimulation. Down regulation of PC1/3 by shRNA produce a similar phenotype in NR8383 to what we previously reported in isolated peritoneal macrophages. PC1/3 shRNA induced changes in the cellular organization and expression of the specific trafficking regulator RAB GTPase. As a consequence, NR8383 down-regulated for PC1/3, present an abnormal cytokine secretion profile. We conclude that the NR8383 cell line represents a good model to study PC1/3 in macrophages and we present PC1/3 as an important regulator of vesicle trafficking and secretion in macrophages.
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Gutiérrez-Martínez E, Fernández-Ulibarri I, Lázaro-Diéguez F, Johannes L, Pyne S, Sarri E, Egea G. Lipid phosphate phosphatase 3 participates in transport carrier formation and protein trafficking in the early secretory pathway. J Cell Sci 2013; 126:2641-55. [PMID: 23591818 DOI: 10.1242/jcs.117705] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The inhibition of phosphatidic acid phosphatase (PAP) activity by propanolol indicates that diacylglycerol (DAG) is required for the formation of transport carriers at the Golgi and for retrograde trafficking to the ER. Here we report that the PAP2 family member lipid phosphate phosphatase 3 (LPP3, also known as PAP2b) localizes in compartments of the secretory pathway from ER export sites to the Golgi complex. The depletion of human LPP3: (i) reduces the number of tubules generated from the ER-Golgi intermediate compartment and the Golgi, with those formed from the Golgi being longer in LPP3-silenced cells than in control cells; (ii) impairs the Rab6-dependent retrograde transport of Shiga toxin subunit B from the Golgi to the ER, but not the anterograde transport of VSV-G or ssDsRed; and (iii) induces a high accumulation of Golgi-associated membrane buds. LPP3 depletion also reduces levels of de novo synthesized DAG and the Golgi-associated DAG contents. Remarkably, overexpression of a catalytically inactive form of LPP3 mimics the effects of LPP3 knockdown on Rab6-dependent retrograde transport. We conclude that LPP3 participates in the formation of retrograde transport carriers at the ER-Golgi interface, where it transitorily cycles, and during its route to the plasma membrane.
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Affiliation(s)
- Enric Gutiérrez-Martínez
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
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Wang L, Shen W, Kazachkov M, Chen G, Chen Q, Carlsson AS, Stymne S, Weselake RJ, Zou J. Metabolic interactions between the Lands cycle and the Kennedy pathway of glycerolipid synthesis in Arabidopsis developing seeds. THE PLANT CELL 2012; 24:4652-69. [PMID: 23150634 PMCID: PMC3531858 DOI: 10.1105/tpc.112.104604] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/12/2012] [Accepted: 10/17/2012] [Indexed: 05/18/2023]
Abstract
It has been widely accepted that the primary function of the Lands cycle is to provide a route for acyl remodeling to modify fatty acid (FA) composition of phospholipids derived from the Kennedy pathway. Lysophosphatidylcholine acyltransferase (LPCAT) is an evolutionarily conserved key enzyme in the Lands cycle. In this study, we provide direct evidence that the Arabidopsis thaliana LPCATs, LPCAT1 and LPCAT2, participate in the Lands cycle in developing seeds. In spite of a substantially reduced initial rate of nascent FA incorporation into phosphatidylcholine (PC), the PC level in the double mutant lpcat1 lpcat2-2 remained unchanged. LPCAT deficiency triggered a compensatory response of de novo PC synthesis and a concomitant acceleration of PC turnover that were attributable at least in part to PC deacylation. Acyl-CoA profile analysis revealed complicated metabolic alterations rather than merely reduced acyl group shuffling from PC in the mutant. Shifts in FA stereo-specific distribution in triacylglycerol of the mutant seed suggested a preferential retention of saturated acyl chains at the stereospecific numbering (sn)-1 position from PC and likely a channeling of lysophosphatidic acid, derived from PC, into the Kennedy pathway. Our study thus illustrates an intricate relationship between the Lands cycle and the Kennedy pathway.
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Affiliation(s)
- Liping Wang
- National Research Council Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Wenyun Shen
- National Research Council Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Michael Kazachkov
- National Research Council Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Guanqun Chen
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
| | - Qilin Chen
- National Research Council Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
| | - Anders S. Carlsson
- Department of Plant Breeding and Biotechnology, Swedish University of Agricultural Sciences, S 230 53 Alnarp, Sweden
| | - Sten Stymne
- Department of Plant Breeding and Biotechnology, Swedish University of Agricultural Sciences, S 230 53 Alnarp, Sweden
| | - Randall J. Weselake
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
| | - Jitao Zou
- National Research Council Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
- Address correspondence to
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42
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Sewell GW, Hannun YA, Han X, Koster G, Bielawski J, Goss V, Smith PJ, Rahman FZ, Vega R, Bloom SL, Walker AP, Postle AD, Segal AW. Lipidomic profiling in Crohn's disease: abnormalities in phosphatidylinositols, with preservation of ceramide, phosphatidylcholine and phosphatidylserine composition. Int J Biochem Cell Biol 2012; 44:1839-46. [PMID: 22728312 PMCID: PMC3778899 DOI: 10.1016/j.biocel.2012.06.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 06/08/2012] [Accepted: 06/12/2012] [Indexed: 11/23/2022]
Abstract
Crohn's disease is a chronic inflammatory condition largely affecting the terminal ileum and large bowel. A contributing cause is the failure of an adequate acute inflammatory response as a result of impaired secretion of pro-inflammatory cytokines by macrophages. This defective secretion arises from aberrant vesicle trafficking, misdirecting the cytokines to lysosomal degradation. Aberrant intestinal permeability is also well-established in Crohn's disease. Both the disordered vesicle trafficking and increased bowel permeability could result from abnormal lipid composition. We thus measured the sphingo- and phospholipid composition of macrophages, using mass spectrometry and stable isotope labelling approaches. Stimulation of macrophages with heat-killed Escherichia coli resulted in three main changes; a significant reduction in the amount of individual ceramide species, an altered composition of phosphatidylcholine, and an increased rate of phosphatidylcholine synthesis in macrophages. These changes were observed in macrophages from both healthy control individuals and patients with Crohn's disease. The only difference detected between control and Crohn's disease macrophages was a reduced proportion of newly-synthesised phosphatidylinositol 16:0/18:1 over a defined time period. Shotgun lipidomics analysis of macroscopically non-inflamed ileal biopsies showed a significant decrease in this same lipid species with overall preservation of sphingolipid, phospholipid and cholesterol composition.
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Key Words
- cct, phosphocholine cytidylyltransferase
- cd, crohn's disease
- gwas, genome-wide association study
- hc, healthycontrol
- hkec, heat-killed escherichia coli
- pa, phosphatidic acid
- pc, phosphatidylcholine
- pi, phosphatidylinositol
- ps, phosphatidylserine
- tnf, tumor necrosis factor
- crohn's disease
- macrophage
- lipids
- ceramide
- sphingolipid
- phospholipid
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Affiliation(s)
- Gavin W. Sewell
- Division of Medicine, UCL, 5 University Street, London, United Kingdom
| | - Yusuf A. Hannun
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Xianlin Han
- Sanford-Burnham Medical Research Institute, Orlando, FL, United States
| | - Grielof Koster
- Division of Infection, Inflammation & Immunity, University of Southampton, School of Medicine, Southampton General Hospital, Mailpoint 803, South Block, Tremona Road, Southampton, United Kingdom
| | - Jacek Bielawski
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Victoria Goss
- Division of Infection, Inflammation & Immunity, University of Southampton, School of Medicine, Southampton General Hospital, Mailpoint 803, South Block, Tremona Road, Southampton, United Kingdom
| | - Philip J. Smith
- Division of Medicine, UCL, 5 University Street, London, United Kingdom
| | - Farooq Z. Rahman
- Department of Gastroenterology, University College Hospital, 235 Euston Road, London, United Kingdom
| | - Roser Vega
- Department of Gastroenterology, University College Hospital, 235 Euston Road, London, United Kingdom
| | - Stuart L. Bloom
- Department of Gastroenterology, University College Hospital, 235 Euston Road, London, United Kingdom
| | - Ann P. Walker
- Division of Medicine, UCL, 5 University Street, London, United Kingdom
| | - Anthony D. Postle
- Division of Infection, Inflammation & Immunity, University of Southampton, School of Medicine, Southampton General Hospital, Mailpoint 803, South Block, Tremona Road, Southampton, United Kingdom
| | - Anthony W. Segal
- Division of Medicine, UCL, 5 University Street, London, United Kingdom
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43
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Phosphatidylcholine and the CDP-choline cycle. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:523-32. [PMID: 23010477 DOI: 10.1016/j.bbalip.2012.09.009] [Citation(s) in RCA: 169] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 09/16/2012] [Indexed: 11/20/2022]
Abstract
The CDP-choline pathway of phosphatidylcholine (PtdCho) biosynthesis was first described more than 50 years ago. Investigation of the CDP-choline pathway in yeast provides a basis for understanding the CDP-choline pathway in mammals. PtdCho is considered as an intermediate in a cycle of synthesis and degradation, and the activity of a CDP-choline cycle is linked to subcellular membrane lipid movement. The components of the mammalian CDP-choline pathway include choline transport, choline kinase, phosphocholine cytidylyltransferase, and choline phosphotransferase activities. The protein isoforms and biochemical mechanisms of regulation of the pathway enzymes are related to their cell- and tissue-specific functions. Regulated PtdCho turnover mediated by phospholipases or neuropathy target esterase participates in the mammalian CDP-choline cycle. Knockout mouse models define the biological functions of the CDP-choline cycle in mammalian cells and tissues. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism.
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44
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UPR-Mediated Membrane Biogenesis in B Cells. Biochem Res Int 2011; 2012:738471. [PMID: 22110962 PMCID: PMC3206326 DOI: 10.1155/2012/738471] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 08/25/2011] [Indexed: 02/04/2023] Open
Abstract
The unfolded protein
response (UPR) can coordinate the regulation of
gene transcription and protein translation to
balance the load of client proteins with the
protein folding and degradative capacities of
the ER. Increasing evidence also implicates the
UPR in the regulation of lipid synthesis and
membrane biogenesis. The differentiation of
B lymphocytes into antibody-secreting cells is
marked by significant expansion of the ER, the
site for antibody synthesis and assembly. In
activated B cells, the demand for membrane
protein and lipid components leads to activation
of the UPR transcriptional activator XBP1(S)
which, in turn, initiates a cascade of
biochemical events that enhance supplies of
phospholipid precursors and build machinery for
the synthesis, maturation, and transport of
secretory proteins. The alterations in lipid
metabolism that occur during this developmental
transition and the impact of membrane
phospholipid restriction on B cell secretory
characteristics are discussed in this
paper.
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45
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Sarri E, Sicart A, Lázaro-Diéguez F, Egea G. Phospholipid synthesis participates in the regulation of diacylglycerol required for membrane trafficking at the Golgi complex. J Biol Chem 2011; 286:28632-43. [PMID: 21700701 DOI: 10.1074/jbc.m111.267534] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The lipid metabolite diacylglycerol (DAG) is required for transport carrier biogenesis at the Golgi, although how cells regulate its levels is not well understood. Phospholipid synthesis involves highly regulated pathways that consume DAG and can contribute to its regulation. Here we altered phosphatidylcholine (PC) and phosphatidylinositol synthesis for a short period of time in CHO cells to evaluate the changes in DAG and its effects in membrane trafficking at the Golgi. We found that cellular DAG rapidly increased when PC synthesis was inhibited at the non-permissive temperature for the rate-limiting step of PC synthesis in CHO-MT58 cells. DAG also increased when choline and inositol were not supplied. The major phospholipid classes and triacylglycerol remained unaltered for both experimental approaches. The analysis of Golgi ultrastructure and membrane trafficking showed that 1) the accumulation of the budding vesicular profiles induced by propanolol was prevented by inhibition of PC synthesis, 2) the density of KDEL receptor-containing punctated structures at the endoplasmic reticulum-Golgi interface correlated with the amount of DAG, and 3) the post-Golgi transport of the yellow fluorescent temperature-sensitive G protein of stomatitis virus and the secretion of a secretory form of HRP were both reduced when DAG was lowered. We confirmed that DAG-consuming reactions of lipid synthesis were present in Golgi-enriched fractions. We conclude that phospholipid synthesis pathways play a significant role to regulate the DAG required in Golgi-dependent membrane trafficking.
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Affiliation(s)
- Elisabet Sarri
- Departament de Biologia Cellular, Immunologia, i Neurociències, Facultat de Medicina and Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, C/ Casanova, 143, E-08036 Barcelona, Spain.
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46
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Cytokine release from innate immune cells: association with diverse membrane trafficking pathways. Blood 2011; 118:9-18. [PMID: 21562044 DOI: 10.1182/blood-2010-08-265892] [Citation(s) in RCA: 252] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cytokines released from innate immune cells play key roles in the regulation of the immune response. These intercellular messengers are the source of soluble regulatory signals that initiate and constrain inflammatory responses to pathogens and injury. Although numerous studies describe detailed signaling pathways induced by cytokines and their specific receptors, there is little information on the mechanisms that control the release of cytokines from different cell types. Indeed, the pathways, molecules, and mechanisms of cytokine release remain a "black box" in immunology. Here, we review research findings and new approaches that have begun to generate information on cytokine trafficking and release by innate immune cells in response to inflammatory or infectious stimuli. Surprisingly complex machinery, multiple organelles, and specialized membrane domains exist in these cells to ensure the selective, temporal, and often polarized release of cytokines in innate immunity.
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47
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Abstract
Cytokine secretion is a widely studied process, although little is known regarding the specific mechanisms that regulate cytokine release. Recent findings have shed light on some of the precise molecular pathways that regulate the packaging of newly synthesized cytokines from immune cells. These findings begin to elucidate pathways and mechanisms that underpin cytokine release in all cells. In this article, we review the highlights of some of these novel discoveries.
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Affiliation(s)
- Amanda C. Stanley
- Institute for Molecular Bioscience, University of Queensland, St. Lucia, Queensland, Australia; and
| | - Paige Lacy
- Pulmonary Research Group, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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48
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Induction of fatty acid synthesis is a key requirement for phagocytic differentiation of human monocytes. Proc Natl Acad Sci U S A 2010; 107:7817-22. [PMID: 20385828 DOI: 10.1073/pnas.0912059107] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Monocytes are precursors of macrophages. Here we demonstrate that macrophage colony-stimulating factor (M-CSF)-dependent differentiation of primary human monocytes from healthy volunteers induces transcription of SREBP-1c target genes required for fatty acid (FA) biosynthesis and impairs transcription of SREBP-2 target genes required for cholesterol synthesis. Detailed lipid metabolic profiling showed that this transcriptional regulation leads to a dramatically increased fatty acid synthesis as driving force for enhanced phospholipid synthesis. During cell differentiation the major lipid class switches from cholesterol in monocytes to phosphatidylcholine in macrophages. Ultrastructural analysis revealed that this transcriptional and metabolic regulation is essential for development of macrophage filopodia and cellular organelles including primary lysosomes, endoplasmic reticulum, and Golgi network. Additional functional studies showed that suppression of fatty acid synthesis prevents phagocytosis representing a central macrophage function. Therefore induction of fatty acid synthesis is a key requirement for phagocyte development and function.
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49
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Leonardi R, Frank MW, Jackson PD, Rock CO, Jackowski S. Elimination of the CDP-ethanolamine pathway disrupts hepatic lipid homeostasis. J Biol Chem 2009; 284:27077-89. [PMID: 19666474 PMCID: PMC2785637 DOI: 10.1074/jbc.m109.031336] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 08/03/2009] [Indexed: 11/06/2022] Open
Abstract
Phosphoethanolamine cytidylyltransferase (ECT) catalyzes the rate-controlling step in a major pathway for the synthesis of phosphatidylethanolamine (PtdEtn). Hepatocyte-specific deletion of the ECT gene in mice resulted in normal appearing animals without overt signs of liver injury or inflammation. The molecular species of PtdEtn in the ECT-deficient livers were significantly altered compared with controls and matched the composition of the phosphatidylserine (PtdSer) pool, illustrating the complete reliance on the PtdSer decarboxylase pathway for PtdEtn synthesis. PtdSer structure was controlled by the substrate specificity of PtdSer synthase that selectively converted phosphatidylcholine molecular species containing stearate paired with a polyunsaturated fatty acid to PtdSer. There was no evidence for fatty acid remodeling of PtdEtn. The elimination of diacylglycerol utilization by the CDP-ethanolamine pathway led to a 10-fold increase in triacylglycerols in the ECT-deficient hepatocytes that became engorged with lipid droplets. Triacylglycerol accumulation was associated with a significant elevation in the expression of the transcription factors and target genes that drive de novo lipogenesis. The absence of the ECT pathway for diacylglycerol utilization at the endoplasmic reticulum triggers increased fatty acid synthesis to support the formation of triacylglycerols leading to liver steatosis.
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Affiliation(s)
- Roberta Leonardi
- From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Matthew W. Frank
- From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Pamela D. Jackson
- From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Charles O. Rock
- From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Suzanne Jackowski
- From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
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50
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Testerink N, van der Sanden MHM, Houweling M, Helms JB, Vaandrager AB. Depletion of phosphatidylcholine affects endoplasmic reticulum morphology and protein traffic at the Golgi complex. J Lipid Res 2009; 50:2182-92. [PMID: 19458387 DOI: 10.1194/jlr.m800660-jlr200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mutant Chinese hamster ovary cell line MT58 contains a thermosensitive mutation in CTP:phosphocholine cytidylyltransferase, the regulatory enzyme in the CDP-choline pathway. As a result, MT58 cells have a 50% decrease in their phosphatidylcholine (PC) level within 24 h when cultured at the nonpermissive temperature (40 degrees C). This is due to a relative rapid breakdown of PC that is not compensated for by the inhibition of de novo PC synthesis. Despite this drastic decrease in cellular PC content, cells are viable and can proliferate by addition of lysophosphatidylcholine. By [(3)H]oleate labeling, we found that the FA moiety of the degraded PC is recovered in triacylglycerol. In accordance with this finding, an accumulation of lipid droplets is seen in MT58 cells. Analysis of PC-depleted MT58 cells by electron and fluorescence microscopy revealed a partial dilation of the rough endoplasmic reticulum, resulting in spherical structures on both sites of the nucleus, whereas the morphology of the plasma membrane, mitochondria, and Golgi complex was unaffected. In contrast to these morphological observations, protein transport from the ER remains intact. Surprisingly, protein transport at the level of the Golgi complex is impaired. Our data suggest that the transport processes at the Golgi complex are regulated by distal changes in lipid metabolism.
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Affiliation(s)
- Nicole Testerink
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, and Institute of Biomembranes, University of Utrecht, 3584 CM, The Netherlands
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