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Zhuang C, Chen R, Zheng Z, Lu J, Hong C. Toll-Like Receptor 3 in Cardiovascular Diseases. Heart Lung Circ 2022; 31:e93-e109. [PMID: 35367134 DOI: 10.1016/j.hlc.2022.02.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 02/08/2022] [Accepted: 02/17/2022] [Indexed: 02/06/2023]
Abstract
Toll-like receptor 3 (TLR3) is an important member of the innate immune response receptor toll-like receptors (TLRs) family, which plays a vital role in regulating immune response, promoting the maturation and differentiation of immune cells, and participating in the response of pro-inflammatory factors. TLR3 is activated by pathogen-associated molecular patterns and damage-associated molecular patterns, which support the pathophysiology of many diseases related to inflammation. An increasing number of studies have confirmed that TLR3, as a crucial medium of innate immunity, participates in the occurrence and development of cardiovascular diseases (CVDs) by regulating the transcription and translation of various cytokines, thus affecting the structure and physiological function of resident cells in the cardiovascular system, including vascular endothelial cells, vascular smooth muscle cells, cardiomyocytes, fibroblasts and macrophages. The dysfunction and structural damage of vascular endothelial cells and proliferation of vascular smooth muscle cells are the key factors in the occurrence of vascular diseases such as pulmonary arterial hypertension, atherosclerosis, myocardial hypertrophy, myocardial infarction, ischaemia/reperfusion injury, and heart failure. Meanwhile, cardiomyocytes, fibroblasts, and macrophages are involved in the development of CVDs. Therefore, the purpose of this review was to explore the latest research published on TLR3 in CVDs and discuss current understanding of potential mechanisms by which TLR3 contributes to CVDs. Even though TLR3 is a developing area, it has strong treatment potential as an immunomodulator and deserves further study for clinical translation.
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Affiliation(s)
- Chunying Zhuang
- China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China; First Clinical School, Guangzhou Medical University, Guangzhou, China
| | - Riken Chen
- China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhenzhen Zheng
- Department of Respiration, The Second Affiliated Hospital of Guangdong Medical University, Guangzhou, China
| | - Jianmin Lu
- China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Cheng Hong
- China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
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2
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Macrophage-Mediated Immune Responses: From Fatty Acids to Oxylipins. MOLECULES (BASEL, SWITZERLAND) 2021; 27:molecules27010152. [PMID: 35011385 PMCID: PMC8746402 DOI: 10.3390/molecules27010152] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 01/21/2023]
Abstract
Macrophages have diverse functions in the pathogenesis, resolution, and repair of inflammatory processes. Elegant studies have elucidated the metabolomic and transcriptomic profiles of activated macrophages. However, the versatility of macrophage responses in inflammation is likely due, at least in part, to their ability to rearrange their repertoire of bioactive lipids, including fatty acids and oxylipins. This review will describe the fatty acids and oxylipins generated by macrophages and their role in type 1 and type 2 immune responses. We will highlight lipidomic studies that have shaped the current understanding of the role of lipids in macrophage polarization.
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3
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Russo M, Montone RA, D'Amario D, Camilli M, Canonico F, Santamaria C, Iannaccone G, Pedicino D, Pidone C, Galli M, Trani C, Severino A, Liuzzo G, Niccoli G, Crea F. Role of perilipin 2 in microvascular obstruction in patients with ST-elevation myocardial infarction. EUROPEAN HEART JOURNAL. ACUTE CARDIOVASCULAR CARE 2021; 10:633-642. [PMID: 33620432 DOI: 10.1093/ehjacc/zuaa004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/27/2020] [Accepted: 07/22/2020] [Indexed: 12/11/2022]
Abstract
AIMS Coronary microvascular obstruction (MVO) occurs frequently in patients with ST-elevation myocardial infarction (STEMI) after percutaneous coronary intervention (PCI). However, mechanisms are multiple and not yet fully understood. Perilipin 2 (PLIN2) is involved in lipid metabolism of macrophages resident in atherosclerotic plaques, along with a role in enhancing plaque inflammation. We studied the association between PLIN2 and MVO in STEMI patients undergoing primary PCI, and we assessed the role of PLIN2 to predict major adverse cardiovascular events (MACEs). METHODS AND RESULTS STEMI patients undergoing primary PCI were enrolled. PLIN2 was evaluated in peripheral blood monocytes; MVO was assessed using coronary angiogram. MACEs, as a composite of cardiac death, non-fatal myocardial infarction, re-admission for heart failure, and target vessel revascularization were investigated at follow-up. Among 100 STEMI patients, 33 (33.0%) had MVO. Patients with MVO had higher levels of PLIN2 (1.03 ± 0.28 vs. 0.90 ± 0.16, P = 0.019). Age [odds ratio (OR) (95% confidence interval, CI), 1.045 (1.005-1.087), P = 0.026] and PLIN2 [OR (95% CI), 16.606 (2.027-136.030), P = 0.009] were associated with MVO at univariate analysis, although only PLIN2 [OR (95% CI), 12.325 (1.446-105.039), P = 0.022] was associated with MVO at multivariate analysis. After a mean follow-up of 182.2 ± 126.6 days, 13 MACEs occurred. MVO [hazard ratio (HR) (95% CI), 6.791 (2.053-22.462), P = 0.002], hypercholesterolaemia [HR (95% CI), 3.563 (1.094-11.599), P = 0.035], and PLIN2 [HR (95% CI), 82.991 (9.857-698.746), P < 0.001] were predictors of MACEs at univariate analysis, although only PLIN2 [HR (95% CI), 26.904 (2.461-294.100), P = 0.007] predicted MACEs at multivariate analysis. CONCLUSIONS In STEMI patients undergoing primary PCI, PLIN2 was independently associated with MVO and was an independent predictor of MACEs at follow-up, suggesting to further explore PLIN2 as a target for future cardioprotection therapies.
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Affiliation(s)
- Michele Russo
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Rocco A Montone
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Domenico D'Amario
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Massimiliano Camilli
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Francesco Canonico
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Claudia Santamaria
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Giulia Iannaccone
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Daniela Pedicino
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Chiara Pidone
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Mattia Galli
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy
| | - Carlo Trani
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy.,Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Anna Severino
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy.,Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Giovanna Liuzzo
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy.,Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Giampaolo Niccoli
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy.,Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
| | - Filippo Crea
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, L.go F. Vito, 1, 00168, Rome, Italy.,Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, L.go F. Vito, 1, 00168 Rome, Italy
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4
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Monson EA, Trenerry AM, Laws JL, Mackenzie JM, Helbig KJ. Lipid droplets and lipid mediators in viral infection and immunity. FEMS Microbiol Rev 2021; 45:fuaa066. [PMID: 33512504 PMCID: PMC8371277 DOI: 10.1093/femsre/fuaa066] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/02/2020] [Indexed: 12/14/2022] Open
Abstract
Lipid droplets (LDs) contribute to key pathways important for the physiology and pathophysiology of cells. In a homeostatic view, LDs regulate the storage of neutral lipids, protein sequestration, removal of toxic lipids and cellular communication; however, recent advancements in the field show these organelles as essential for various cellular stress response mechanisms, including inflammation and immunity, with LDs acting as hubs that integrate metabolic and inflammatory processes. The accumulation of LDs has become a hallmark of infection, and is often thought to be virally driven; however, recent evidence is pointing to a role for the upregulation of LDs in the production of a successful immune response to viral infection. The fatty acids housed in LDs are also gaining interest due to the role that these lipid species play during viral infection, and their link to the synthesis of bioactive lipid mediators that have been found to have a very complex role in viral infection. This review explores the role of LDs and their subsequent lipid mediators during viral infections and poses a paradigm shift in thinking in the field, whereby LDs may play pivotal roles in protecting the host against viral infection.
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Affiliation(s)
- Ebony A Monson
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Alice M Trenerry
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Jay L Laws
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Karla J Helbig
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
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5
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Brandenburg J, Marwitz S, Tazoll SC, Waldow F, Kalsdorf B, Vierbuchen T, Scholzen T, Gross A, Goldenbaum S, Hölscher A, Hein M, Linnemann L, Reimann M, Kispert A, Leitges M, Rupp J, Lange C, Niemann S, Behrends J, Goldmann T, Heine H, Schaible UE, Hölscher C, Schwudke D, Reiling N. WNT6/ACC2-induced storage of triacylglycerols in macrophages is exploited by Mycobacterium tuberculosis. J Clin Invest 2021; 131:e141833. [PMID: 34255743 DOI: 10.1172/jci141833] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 07/06/2021] [Indexed: 11/17/2022] Open
Abstract
In view of emerging drug-resistant tuberculosis (TB), host-directed adjunct therapies are urgently needed to improve treatment outcomes with currently available anti-TB therapies. One approach is to interfere with the formation of lipid-laden "foamy" macrophages in the host, as they provide a nutrient-rich host cell environment for Mycobacterium tuberculosis (Mtb). Here, we provide evidence that Wnt family member 6 (WNT6), a ligand of the evolutionarily conserved Wingless/Integrase 1 (WNT) signaling pathway, promotes foam cell formation by regulating key lipid metabolic genes including acetyl-CoA carboxylase 2 (ACC2) during pulmonary TB. Using genetic and pharmacological approaches, we demonstrated that lack of functional WNT6 or ACC2 significantly reduced intracellular triacylglycerol (TAG) levels and Mtb survival in macrophages. Moreover, treatment of Mtb-infected mice with a combination of a pharmacological ACC2 inhibitor and the anti-TB drug isoniazid (INH) reduced lung TAG and cytokine levels, as well as lung weights, compared with treatment with INH alone. This combination also reduced Mtb bacterial numbers and the size of mononuclear cell infiltrates in livers of infected mice. In summary, our findings demonstrate that Mtb exploits WNT6/ACC2-induced storage of TAGs in macrophages to facilitate its intracellular survival, a finding that opens new perspectives for host-directed adjunctive treatment of pulmonary TB.
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Affiliation(s)
- Julius Brandenburg
- Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, Borstel, Germany.,German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Sebastian Marwitz
- Pathology, Research Center Borstel, Borstel, Germany.,Airway Research Center North (ARCN), Member of the German Center for Lung Research (DZL), Grosshansdorf, Germany
| | - Simone C Tazoll
- Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Franziska Waldow
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Bioanalytical Chemistry
| | - Barbara Kalsdorf
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Clinical Infectious Diseases
| | | | | | - Annette Gross
- Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Svenja Goldenbaum
- Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | | | | | - Lara Linnemann
- Cellular Microbiology, Research Center Borstel, Borstel, Germany
| | | | - Andreas Kispert
- Institute for Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Michael Leitges
- Division of BioMedical Sciences/Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Jan Rupp
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Department of Infectious Diseases and Microbiology and
| | - Christoph Lange
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Clinical Infectious Diseases.,Respiratory Medicine & International Health, University of Lübeck, Lübeck, Germany.,Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Stefan Niemann
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Molecular and Experimental Mycobacteriology, Research Center Borstel, Borstel, Germany
| | | | - Torsten Goldmann
- Pathology, Research Center Borstel, Borstel, Germany.,Airway Research Center North (ARCN), Member of the German Center for Lung Research (DZL), Grosshansdorf, Germany
| | | | - Ulrich E Schaible
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Cellular Microbiology, Research Center Borstel, Borstel, Germany
| | - Christoph Hölscher
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Infection Immunology, and
| | - Dominik Schwudke
- German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.,Airway Research Center North (ARCN), Member of the German Center for Lung Research (DZL), Grosshansdorf, Germany.,Bioanalytical Chemistry
| | - Norbert Reiling
- Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, Borstel, Germany.,German Center for Infection Research (DZIF), Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
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6
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Lei CX, Tian JJ, Zhang W, Li YP, Ji H, Yu EM, Gong WB, Li ZF, Zhang K, Wang GJ, Yu DG, Xie J. Lipid droplets participate in modulating innate immune genes in Ctenopharyngodon idella kidney cells. FISH & SHELLFISH IMMUNOLOGY 2019; 88:595-605. [PMID: 30890432 DOI: 10.1016/j.fsi.2019.03.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/06/2019] [Accepted: 03/13/2019] [Indexed: 06/09/2023]
Abstract
Lipid droplets (LDs) are increasingly being recognized as important immune modulators in mammals, in additional to their function of lipid ester deposition. However, the role of LDs in fish immunity remains poorly understood. In this study, the function of LDs in the innate immune response of Ctenopharyngodon idella kidney (CIK) cells, which are the equivalent of myeloid cells in vertebrates, was investigated. LD number and TG content significantly increased in the CIK cells following exposure to lipopolysaccharide (LPS), peptidoglycan (PGN), and polyriboinosinic-polyribocytidylic acid (Poly [I: C]) for 24 h, accompanied by increases in the relative expression of several innate immune genes. However, fatty acid compositions of the triglycerides were not changed after treatment with these three pathogenic mimics. LPS, PGN, and Poly (I: C) did not alter the relative expressions of lipogenic (FAS, SCD, and DGAT) and lipid catabolic (PPARα, ATGL, and CPT-1) genes. However, these treatments did increase the mRNA levels of lipid transportation genes (FATP/CD36, ACSL1, and ACSL4), and also decreased the non-esterified fatty acid level in the medium. To further explore the role of LDs in the immune response, CIK cells were incubated with different concentrations (0, 100, 200, 300, 400, 500 μM) of exogenous lipid mix (LM; oleic acid [OA]:linoleic acid [LA]:linolenic acid [LNA] = 2:1:1), and were then transferred to a lipid-free medium and incubated for 24 h. LD size and number increased with the increase in lipid levels, and this was accompanied by increased expression of innate immune genes, including MyD88, IRF3, and IL-1β, which were expressed at their highest levels in 300 μM exogenous lipid mix. Interestingly, after incubating with different fatty acids (LM, OA, LA, LNA, arachidonic acid [ARA], and docosahexaenoic acid [DHA]; 300 μM), ARA and DHA were more potent in inducing LD formation and innate immune gene expression in the CIK cells. Finally, atglistatin, an ATGL inhibitor, effectively attenuated the expression of most genes upregulated by ARA or DHA, suggesting that lipolysis may be involved in the regulation of immune genes at the transcriptional level. Overall, the findings of this study demonstrate that LDs are functional organelles that could act as modulators in the innate immune response of CIK cells. Additionally, long-chain polyunsaturated fatty acid enriched LDs play a unique role in regulating this process.
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Affiliation(s)
- Cai-Xia Lei
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China; College of Marine Sciences, South China Agriculture University, Guangzhou, 510640, PR China
| | - Jing-Jing Tian
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China.
| | - Wen Zhang
- College of Biological Science and Agriculture, QianNan Normal University for Nationalities, Duyun, 558000, PR China
| | - Yu-Ping Li
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Hong Ji
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, PR China
| | - Er-Meng Yu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Wang-Bao Gong
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Zhi-Fei Li
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Kai Zhang
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Guang-Jun Wang
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - De-Guang Yu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China
| | - Jun Xie
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China.
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7
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Abstract
Fatty acid-binding proteins (FABPs), a family of lipid chaperones, contribute to systemic metabolic regulation via several lipid signaling pathways. Fatty acid-binding protein 4 (FABP4), known as adipocyte FABP (A-FABP) or aP2, is mainly expressed in adipocytes and macrophages and plays important roles in the development of insulin resistance and atherosclerosis in relation to metabolically driven low-grade and chronic inflammation, referred to as ‘metaflammation’. FABP4 is secreted from adipocytes in a non-classical pathway associated with lipolysis and acts as an adipokine for the development of insulin resistance and atherosclerosis. Circulating FABP4 levels are associated with several aspects of metabolic syndrome and cardiovascular disease. Ectopic expression and function of FABP4 in cells and tissues are also related to the pathogenesis of several diseases. Pharmacological modification of FABP4 function by specific inhibitors, neutralizing antibodies or antagonists of unidentified receptors would be novel therapeutic strategies for several diseases, including obesity, diabetes mellitus, atherosclerosis and cardiovascular disease. Significant roles of FABP4 as a lipid chaperone in physiological and pathophysiological conditions and the possibility of FABP4 being a therapeutic target for metabolic and cardiovascular diseases are discussed in this review.
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Affiliation(s)
- Masato Furuhashi
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine
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8
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den Brok MH, Raaijmakers TK, Collado-Camps E, Adema GJ. Lipid Droplets as Immune Modulators in Myeloid Cells. Trends Immunol 2018; 39:380-392. [DOI: 10.1016/j.it.2018.01.012] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/14/2017] [Accepted: 01/23/2018] [Indexed: 12/23/2022]
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9
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Ntokou A, Szibor M, Rodríguez-Castillo JA, Quantius J, Herold S, El Agha E, Bellusci S, Salwig I, Braun T, Voswinckel R, Seeger W, Morty RE, Ahlbrecht K. A novel mouse Cre-driver line targeting Perilipin 2-expressing cells in the neonatal lung. Genesis 2017; 55. [PMID: 29045046 DOI: 10.1002/dvg.23080] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 10/13/2017] [Accepted: 10/13/2017] [Indexed: 12/21/2022]
Abstract
Pulmonary diseases such as chronic obstructive pulmonary disease, lung fibrosis, and bronchopulmonary dysplasia are characterized by the destruction or malformation of the alveolar regions of the lung. The underlying pathomechanisms at play are an area of intense interest since these mechanisms may reveal pathways suitable for interventions to drive reparative processes. Lipid-laden fibroblasts (lipofibroblasts) express the Perilipin 2 (Plin2) gene-product, PLIN2, commonly called adipose-differentiation related protein (ADRP). These cells are also thought to play a role in alveolarization and repair after injury to the alveolus. Progress in defining the functional contribution of lipofibroblasts to alveolar generation and repair is hampered by a lack of in vivo tools. The present study reports the generation of an inducible mouse Cre-driver line to target cells of the ADRP lineage. Robust Cre-mediated recombination in this mouse line was detected in mesenchymal cells of the postnatal lung, and in additional organs including the heart, liver, and spleen. The generation and validation of this valuable new tool to genetically target, manipulate, and trace cells of the ADRP lineage is critical for assessing the functional contribution of lipofibroblasts to lung development and repair.
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Affiliation(s)
- Aglaia Ntokou
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Marten Szibor
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany.,Institute of Biotechnology, Viikinkaari 5, Helsinki, FI-00790, Finland
| | - José Alberto Rodríguez-Castillo
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Jennifer Quantius
- Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Susanne Herold
- Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Elie El Agha
- Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Saverio Bellusci
- Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Isabelle Salwig
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Thomas Braun
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Robert Voswinckel
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Werner Seeger
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Katrin Ahlbrecht
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), Universities of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
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10
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Li X, Xue W, Liu Y, Li W, Fan D, Zhu C, Wang Y. HLC/pullulan and pullulan hydrogels: their microstructure, engineering process and biocompatibility. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 58:1046-57. [DOI: 10.1016/j.msec.2015.09.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/07/2015] [Indexed: 01/21/2023]
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11
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Pourcet B, Staels B. Perilipin2/adipophilin and ApoA-1 team up to combat atherosclerosis. Cardiovasc Res 2015; 109:193-5. [PMID: 26705365 DOI: 10.1093/cvr/cvv276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Benoit Pourcet
- Univ. Lille, U1011 - EGID, Lille F-59000, France Inserm, U1011, Lille F-59000, France Institut Pasteur de Lille, Lille F-59000, France
| | - Bart Staels
- Univ. Lille, U1011 - EGID, Lille F-59000, France Inserm, U1011, Lille F-59000, France Institut Pasteur de Lille, Lille F-59000, France
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12
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Luo H, Wang J, Qiao C, Ma N, Liu D, Zhang W. Pycnogenol attenuates atherosclerosis by regulating lipid metabolism through the TLR4-NF-κB pathway. Exp Mol Med 2015; 47:e191. [PMID: 26492950 PMCID: PMC4673476 DOI: 10.1038/emm.2015.74] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/10/2015] [Accepted: 06/16/2015] [Indexed: 12/30/2022] Open
Abstract
Atherosclerosis is a leading cause of death worldwide and is characterized by lipid-laden foam cell formation. Recently, pycnogenol (PYC) has drawn much attention because of its prominent effect on cardiovascular disease (CVD). However, its protective effect against atherosclerosis and the underlying mechanism remains undefined. Here PYC treatment reduced areas of plaque and lipid deposition in atherosclerotic mice, concomitant with decreases in total cholesterol and triglyceride levels and increases in HDL cholesterol levels, indicating a potential antiatherosclerotic effect of PYC through the regulation of lipid levels. Additionally, PYC preconditioning markedly decreased foam cell formation and lipid accumulation in lipopolysaccharide (LPS)-stimulated human THP-1 monocytes. A mechanistic analysis indicated that PYC decreased the lipid-related protein expression of adipose differentiation-related protein (ADRP) and adipocyte lipid-binding protein (ALBP/aP2) in a dose-dependent manner. Further analysis confirmed that PYC attenuated LPS-induced lipid droplet formation via ADRP and ALBP expression through the Toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) pathway, because pretreatment with anti-TLR4 antibody or a specific inhibitor of NF-κB (PDTC) strikingly mitigated the LPS-induced increase in ADRP and ALBP. Together, our results provide insight into the ability of PYC to attenuate bacterial infection-triggered pathological processes associated with atherosclerosis. Thus PYC may be a potential lead compound for the future development of antiatherosclerotic CVD therapy.
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Affiliation(s)
- Hong Luo
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Henan, China
| | - Jing Wang
- Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Henan, China
| | - Chenhui Qiao
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Henan, China
| | - Ning Ma
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Henan, China
| | - Donghai Liu
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Henan, China
| | - Weihua Zhang
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Henan, China
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Arisqueta L, Navarro-Imaz H, Rueda Y, Fresnedo O. Cholesterol mobilization from hepatic lipid droplets during endotoxemia is altered in obese ob/ob mice. J Biochem 2015; 158:321-9. [DOI: 10.1093/jb/mvv047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 03/31/2015] [Indexed: 11/12/2022] Open
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Guijas C, Rodríguez JP, Rubio JM, Balboa MA, Balsinde J. Phospholipase A2 regulation of lipid droplet formation. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1841:1661-71. [PMID: 25450448 DOI: 10.1016/j.bbalip.2014.10.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/02/2014] [Accepted: 10/14/2014] [Indexed: 02/07/2023]
Abstract
The classical regard of lipid droplets as mere static energy-storage organelles has evolved dramatically. Nowadays these organelles are known to participate in key processes of cell homeostasis, and their abnormal regulation is linked to several disorders including metabolic diseases (diabetes, obesity, atherosclerosis or hepatic steatosis), inflammatory responses in leukocytes, cancer development and neurodegenerative diseases. Hence, the importance of unraveling the cell mechanisms controlling lipid droplet biosynthesis, homeostasis and degradation seems evident Phospholipase A2s, a family of enzymes whose common feature is to hydrolyze the fatty acid present at the sn-2 position of phospholipids, play pivotal roles in cell signaling and inflammation. These enzymes have recently emerged as key regulators of lipid droplet homeostasis, regulating their formation at different levels. This review summarizes recent results on the roles that various phospholipase A2 forms play in the regulation of lipid droplet biogenesis under different conditions. These roles expand the already wide range of functions that these enzymes play in cell physiology and pathophysiology.
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Chang PKY, Khatchadourian A, McKinney RA, Maysinger D. Docosahexaenoic acid (DHA): a modulator of microglia activity and dendritic spine morphology. J Neuroinflammation 2015; 12:34. [PMID: 25889069 PMCID: PMC4344754 DOI: 10.1186/s12974-015-0244-5] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 01/11/2015] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Recent studies have revealed that excessive activation of microglia and inflammation-mediated neurotoxicity are implicated in the progression of several neurological disorders. In particular, chronic inflammation in vivo and exposure of cultured brain cells to lipopolysaccharide (LPS) in vitro can adversely change microglial morphology and function. This can have both direct and indirect effects on synaptic structures and functions. The integrity of dendritic spines, the postsynaptic component of excitatory synapses, dictates synaptic efficacy. Interestingly, dysgenesis of dendritic spines has been found in many neurological diseases associated with ω-3 polyunsaturated fatty acid (PUFA) deficiency and cognitive decline. In contrast, supplemented ω-3 PUFAs, such as docosahexaenoic acid (DHA), can partly correct spine defects. Hence, we hypothesize that DHA directly affects synaptic integrity and indirectly through neuron-glia interaction. Strong activation of microglia by LPS is accompanied by marked release of nitric oxide and formation of lipid bodies (LBs), both dynamic biomarkers of inflammation. Here we investigated direct effects of DHA on synaptic integrity and its indirect effects via microglia in the hippocampal CA1 region. METHODS Microglia (N9) and organotypic hippocampal slice cultures were exposed to the proinflammagen LPS (100 ng/ml) for 24 h. Biochemical and morphological markers of inflammation were investigated in microglia and CA1 regions of hippocampal slices. As biomarkers of hyperactive microglia, mitochondrial function, nitric oxide release and LBs (number, size, LB surface-associated proteins) were assessed. Changes in synaptic transmission of CA1 pyramidal cells were determined following LPS and DHA (25-50 μM) treatments by recording spontaneous AMPA-mediated miniature excitatory postsynaptic currents (mEPSCs). RESULTS Microglia responded to LPS stimulation with a significant decrease of mitochondrial function, increased nitric oxide production and an increase in the formation of large LBs. LPS treatment led to a significant reduction of dendritic spine densities and an increase in the AMPA-mediated mEPSC inter-event interval (IEI). DHA normalized the LPS-induced abnormalities in both neurons and microglia, as revealed by the restoration of synaptic structures and functions in hippocampal CA1 pyramidal neurons. CONCLUSION Our findings indicate that DHA can prevent LPS-induced abnormalities (neuroinflammation) by reducing inflammatory biomarkers, thereby normalizing microglia activity and their effect on synaptic function.
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Affiliation(s)
- Philip K-Y Chang
- Department of Pharmacology and Therapeutics, McGill University, McIntyre Medical Building, Room 1314, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada.
| | - Armen Khatchadourian
- Department of Pharmacology and Therapeutics, McGill University, McIntyre Medical Building, Room 1314, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada.
| | - Rebecca Anne McKinney
- Department of Pharmacology and Therapeutics, McGill University, McIntyre Medical Building, Room 1314, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada. .,Department of Pharmacology & Therapeutics, Bellini Life Science Complex, McGill University, Room 167, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada.
| | - Dusica Maysinger
- Department of Pharmacology and Therapeutics, McGill University, McIntyre Medical Building, Room 1314, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada.
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Furuhashi M, Saitoh S, Shimamoto K, Miura T. Fatty Acid-Binding Protein 4 (FABP4): Pathophysiological Insights and Potent Clinical Biomarker of Metabolic and Cardiovascular Diseases. CLINICAL MEDICINE INSIGHTS-CARDIOLOGY 2015; 8:23-33. [PMID: 25674026 PMCID: PMC4315049 DOI: 10.4137/cmc.s17067] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/16/2014] [Accepted: 12/16/2014] [Indexed: 12/13/2022]
Abstract
Over the past decade, evidences of an integration of metabolic and inflammatory pathways, referred to as metaflammation in several aspects of metabolic syndrome, have been accumulating. Fatty acid-binding protein 4 (FABP4), also known as adipocyte FABP (A-FABP) or aP2, is mainly expressed in adipocytes and macrophages and plays an important role in the development of insulin resistance and atherosclerosis in relation to metaflammation. Despite lack of a typical secretory signal peptide, FABP4 has been shown to be released from adipocytes in a non-classical pathway associated with lipolysis, possibly acting as an adipokine. Elevation of circulating FABP4 levels is associated with obesity, insulin resistance, diabetes mellitus, hypertension, cardiac dysfunction, atherosclerosis, and cardiovascular events. Furthermore, ectopic expression and function of FABP4 in several types of cells and tissues have been recently demonstrated. Here, we discuss both the significant role of FABP4 in pathophysiological insights and its usefulness as a biomarker of metabolic and cardiovascular diseases.
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Affiliation(s)
- Masato Furuhashi
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Shigeyuki Saitoh
- Department of Nursing, Division of Medical and Behavioral Subjects, Sapporo Medical University School of Health Sciences, Sapporo, Japan
| | | | - Tetsuji Miura
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
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Effect of toll-like receptor agonists on the formation of macrophage/foam cells upon acute peritonitis in mice. Bull Exp Biol Med 2014; 156:49-52. [PMID: 24319727 DOI: 10.1007/s10517-013-2275-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We studied effects of zymosan, double-stranded RNA, LPS of E. coli and bacterial CpG DNA, agonists of toll-like receptor TLR2, TLR3, TLR4 and TLR9, respectively, on the formation of macrophage/foam cells 24 h after induction of acute peritonitis. Administration of agonists led to transformation of peritoneal macrophages into foam cells and significant activation of cell biosynthesis and increased the content of triglycerides and cholesterol esters in the absence of LDL and irrespective of the capacity of TLR agonists to stimulate neutrophil infiltration and TNF-α production in the peritoneal cavity.
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Critical role of TLR2 and MyD88 for functional response of macrophages to a group IIA-secreted phospholipase A2 from snake venom. PLoS One 2014; 9:e93741. [PMID: 24718259 PMCID: PMC3981733 DOI: 10.1371/journal.pone.0093741] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 03/06/2014] [Indexed: 01/10/2023] Open
Abstract
The snake venom MT-III is a group IIA secreted phospholipase A2 (sPLA2) enzyme with functional and structural similarities with mammalian pro-inflammatory sPLA2s of the same group. Previously, we demonstrated that MT-III directly activates the innate inflammatory response of macrophages, including release of inflammatory mediators and formation of lipid droplets (LDs). However, the mechanisms coordinating these processes remain unclear. In the present study, by using TLR2−/− or MyD88−/− or C57BL/6 (WT) male mice, we report that TLR2 and MyD88 signaling have a critical role in MT-III-induced inflammatory response in macrophages. MT-III caused a marked release of PGE2, PGD2, PGJ2, IL-1β and IL-10 and increased the number of LDs in WT macrophages. In MT-III-stimulated TLR2−/− macrophages, formation of LDs and release of eicosanoids and cytokines were abrogated. In MyD88−/− macrophages, MT-III-induced release of PGE2, IL-1β and IL-10 was abrogated, but release of PGD2 and PGJ2 was maintained. In addition, COX-2 protein expression seen in MT-III-stimulated WT macrophages was abolished in both TLR2−/− and MyD88−/− cells, while perilipin 2 expression was abolished only in MyD88−/− cells. We further demonstrated a reduction of saturated, monounsaturated and polyunsaturated fatty acids and a release of the TLR2 agonists palmitic and oleic acid from MT-III-stimulated WT macrophages compared with WT control cells, thus suggesting these fatty acids as major messengers for MT-III-induced engagement of TLR2/MyD88 signaling. Collectively, our findings identify for the first time a TLR2 and MyD88-dependent mechanism that underlies group IIA sPLA2-induced inflammatory response in macrophages.
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Cole JE, Mitra AT, Monaco C. Treating atherosclerosis: the potential of Toll-like receptors as therapeutic targets. Expert Rev Cardiovasc Ther 2014; 8:1619-35. [DOI: 10.1586/erc.10.149] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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20
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Feng X, Yuan Y, Wang C, Feng J, Yuan Z, Zhang X, Sui W, Hu P, Zheng P, Ye J. Autophagy involved in lipopolysaccharide-induced foam cell formation is mediated by adipose differentiation-related protein. Lipids Health Dis 2014; 13:10. [PMID: 24405744 PMCID: PMC3896829 DOI: 10.1186/1476-511x-13-10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 01/07/2014] [Indexed: 02/02/2023] Open
Abstract
Background Autophagy is an essential process for breaking down macromolecules and aged/damaged cellular organelles to maintain cellular energy balance and cellular nutritional status. The idea that autophagy regulates lipid metabolism is an emerging concept with important implications for atherosclerosis. However, the potential role of autophagy and its relationship with lipid metabolism in foam cell formation remains unclear. In this study, we found that autophagy was involved in the lipopolysaccharide (LPS)-induced the formation of foam cells and was at least partially dependent on adipose differentiation-related protein (ADRP). Method Foam cell formation was evaluated by Oil red O staining. Autophagic activity was determined by immunofluorescence and Western blotting. ADRP gene expression of ADRP was examined by real-time PCR (RT-PCR). The protein expression of ADRP and LC3 was measured using Western blotting analysis. Intracellular cholesterol and triglyceride levels in foam cells were quantitatively measured by enzymatic colorimetric assays. Results LPS promoted foam cell formation by inducing lipid accumulation in macrophages. The activation of autophagy with rapamycin (Rap) decreased intracellular cholesterol and triglyceride levels, whereas the inhibition of autophagy with 3-methyladenine (3MA) enhanced the accumulation of lipid droplets. Overexpression of ADRP alone increased the formation of foam cells and consequently autophagic activity. In contrast, the inhibitory effects of ADRP activity with siRNA suppressed the activation of autophagy. Taken together, we propose a novel role for ADRP in the regulation of macrophage autophagy during LPS stimulation. Conclusion We defined a new molecular pathway in which LPS-induced foam cell formation is regulated through autophagy. These findings facilitate the understanding of the role of autophagy in the development of atherosclerosis.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Jing Ye
- Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China.
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Huang YL, Morales-Rosado J, Ray J, Myers TG, Kho T, Lu M, Munford RS. Toll-like receptor agonists promote prolonged triglyceride storage in macrophages. J Biol Chem 2013; 289:3001-12. [PMID: 24337578 DOI: 10.1074/jbc.m113.524587] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Macrophages in infected tissues may sense microbial molecules that significantly alter their metabolism. In a seeming paradox, these critical host defense cells often respond by increasing glucose catabolism while simultaneously storing fatty acids (FA) as triglycerides (TAG) in lipid droplets. We used a load-chase strategy to study the mechanisms that promote long term retention of TAG in murine and human macrophages. Toll-like receptor (TLR)1/2, TLR3, and TLR4 agonists all induced the cells to retain TAG for ≥3 days. Prolonged TAG retention was accompanied by the following: (a) enhanced FA uptake and FA incorporation into TAG, with long lasting increases in acyl-CoA synthetase long 1 (ACSL1) and diacylglycerol acyltransferase-2 (DGAT2), and (b) decreases in lipolysis and FA β-oxidation that paralleled a prolonged drop in adipose triglyceride lipase (ATGL). TLR agonist-induced TAG storage is a multifaceted process that persists long after most early pro-inflammatory responses have subsided and may contribute to the formation of "lipid-laden" macrophages in infected tissues.
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Affiliation(s)
- Ying-ling Huang
- From the Antibacterial Host Defense Section, Laboratory of Clinical Infectious Diseases
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Abstract
A key function of the skin is to provide a permeability barrier to restrict the movement of water, electrolytes, and other small molecules between the outside environment and the internal milieu. Following disruption of the permeability barrier, there is a rapid restoration of barrier function, and one of the key signals initiating this repair response is a decrease in the concentration of calcium in the outer epidermis. In this issue, Borkowski et al. present evidence showing that activation of Toll receptor 3 by double-stranded RNA may be another pathway for activation of permeability barrier repair. These results provide further evidence for a link between innate immunity and the permeability barrier.
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Affiliation(s)
- Kenneth R Feingold
- Metabolism Section (111F), Department of Veterans Affairs Medical Center, University of California, San Francisco, San Francisco, California 94121, USA.
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Involvement of lipid droplets in hepatic responses to lipopolysaccharide treatment in mice. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1357-67. [DOI: 10.1016/j.bbalip.2013.04.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 04/05/2013] [Accepted: 04/30/2013] [Indexed: 01/07/2023]
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Gally F, Chu HW, Bowler RP. Cigarette smoke decreases airway epithelial FABP5 expression and promotes Pseudomonas aeruginosa infection. PLoS One 2013; 8:e51784. [PMID: 23349676 PMCID: PMC3551956 DOI: 10.1371/journal.pone.0051784] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 11/06/2012] [Indexed: 12/21/2022] Open
Abstract
Cigarette smoking is the primary cause of Chronic Obstructive Pulmonary Disease (COPD), which is characterized by chronic inflammation of the airways and destruction of lung parenchyma. Repeated and sustained bacterial infections are clearly linked to disease pathogenesis (e.g., exacerbations) and a huge burden on health care costs. The airway epithelium constitutes the first line of host defense against infection and our previous study indicated that Fatty Acid Binding Protein 5 (FABP5) is down regulated in airway epithelial cells of smokers with COPD as compared to smokers without COPD. We hypothesized that cigarette smoke (CS) exposure down regulates FABP5, thus, contributing to a more sustained inflammation in response to bacterial infection. In this report, we show that FABP5 is increased following bacterial infection but decreased following CS exposure of primary normal human bronchial epithelial (NHBE) cells. The goal of this study was to address FABP5 function by knocking down or overexpressing FABP5 in primary NHBE cells exposed to CS. Our data indicate that FABP5 down regulation results in increased P. aeruginosa bacterial load and inflammatory cytokine levels (e.g., IL-8) and decreased expression of the anti-bacterial peptide, β defensin-2. On the contrary, FABP5 overexpression exerts a protective function in airway epithelial cells against P. aeruginosa infection by limiting the production of IL-8 and increasing the expression of β defensin-2. Our study indicates that FABP5 exerts immunomodulatory functions in the airway epithelium against CS exposure and subsequent bacterial infection through its modulation of the nuclear receptor peroxisome proliferator-activated receptor (PPAR)-γ activity. These findings support the development of FABP5/PPAR-γ-targeted therapeutic approach to prevent airway inflammation by restoring antimicrobial immunity during COPD exacerbations.
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Affiliation(s)
- Fabienne Gally
- Pulmonary Division, Department of Medicine, National Jewish Health, Denver, Colorado, United States of America
| | - Hong Wei Chu
- Pulmonary Division, Department of Medicine, National Jewish Health, Denver, Colorado, United States of America
| | - Russell P. Bowler
- Pulmonary Division, Department of Medicine, National Jewish Health, Denver, Colorado, United States of America
- * E-mail:
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Martinet W, De Meyer I, Verheye S, Schrijvers DM, Timmermans JP, De Meyer GRY. Drug-induced macrophage autophagy in atherosclerosis: for better or worse? Basic Res Cardiol 2012; 108:321. [PMID: 23233268 DOI: 10.1007/s00395-012-0321-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 12/04/2012] [Accepted: 12/04/2012] [Indexed: 12/15/2022]
Abstract
Autophagy is a reparative, life-sustaining process by which cytoplasmic components are sequestered in double membrane vesicles and degraded upon fusion with lysosomal compartments. Mice with a macrophage-specific deletion of the essential autophagy gene Atg5 develop plaques with increased apoptosis and oxidative stress as well as enhanced plaque necrosis. This finding indicates that basal autophagy in macrophages is anti-apoptotic and present in atherosclerotic plaques to protect macrophages against various atherogenic stressors. However, autophagy is impaired in advanced stages of atherosclerosis and its deficiency promotes atherosclerosis in part through activation of the inflammasome. Because basal autophagy can be intensified selectively in macrophages by specific drugs such as mammalian target of rapamycin (mTOR) inhibitors or Toll-like receptor 7 (TLR7) ligands, these drugs were recently tested as potential plaque stabilizing compounds. Stent-based delivery of the mTOR inhibitor everolimus promotes a stable plaque phenotype, whereas local administration of the TLR7 ligand imiquimod stimulates inflammation and plaque progression. Therefore, more drugs capable of inducing autophagy should be tested in plaque macrophages to evaluate the feasibility of this approach. Given that drug-induced macrophage autophagy is associated with pro-inflammatory responses due to cytokine release, induction of postautophagic necrosis or activation of phagocytes after clearance of the autophagic corpse, cotreatment with anti-inflammatory compounds may be required. Overall, this review highlights the pros and cons of macrophage autophagy as a drug target for plaque stabilization.
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Affiliation(s)
- Wim Martinet
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium.
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Feingold KR, Shigenaga JK, Kazemi MR, McDonald CM, Patzek SM, Cross AS, Moser A, Grunfeld C. Mechanisms of triglyceride accumulation in activated macrophages. J Leukoc Biol 2012; 92:829-39. [PMID: 22753953 DOI: 10.1189/jlb.1111537] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
LPS treatment of macrophages induces TG accumulation, which is accentuated by TG-rich lipoproteins or FFA. We defined pathways altered during macrophage activation that contribute to TG accumulation. Glucose uptake increased with activation, accompanied by increased GLUT1. Oxidation of glucose markedly decreased, whereas incorporation of glucose-derived carbon into FA and sterols increased. Macrophage activation also increased uptake of FFA, associated with an increase in CD36. Oxidation of FA was markedly reduced, whereas the incorporation of FA into TGs increased, associated with increased GPAT3 and DGAT2. Additionally, macrophage activation decreased TG lipolysis; however, expression of ATGL or HSL was not altered. Macrophage activation altered gene expression similarly when incubated with exogenous FA or AcLDL. Whereas activation with ligands of TLR2 (zymosan), TLR3 (poly I:C), or TLR4 (LPS) induced alterations in macrophage gene expression, leading to TG accumulation, treatment of macrophages with cytokines had minimal effects. Thus, activation of TLRs leads to accumulation of TG in macrophages by multiple pathways that may have beneficial effects in host defense but could contribute to the accelerated atherosclerosis in chronic infections and inflammatory diseases.
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Affiliation(s)
- Kenneth R Feingold
- Metabolism Section, Department of Veterans Affairs Medical Center, University of California, San Francisco, San Francisco, CA, USA.
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27
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Karper JC, Ewing MM, Habets KLL, de Vries MR, Peters EAB, van Oeveren-Rietdijk AM, de Boer HC, Hamming JF, Kuiper J, Kandimalla ER, La Monica N, Jukema JW, Quax PHA. Blocking toll-like receptors 7 and 9 reduces postinterventional remodeling via reduced macrophage activation, foam cell formation, and migration. Arterioscler Thromb Vasc Biol 2012; 32:e72-80. [PMID: 22628437 DOI: 10.1161/atvbaha.112.249391] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE The role of toll-like receptors (TLRs) in vascular remodeling is well established. However, the involvement of the endosomal TLRs is unknown. Here, we study the effect of combined blocking of TLR7 and TLR9 on postinterventional remodeling and accelerated atherosclerosis. METHODS AND RESULTS In hypercholesterolemic apolipoprotein E*3-Leiden mice, femoral artery cuff placement led to strong increase of TLR7 and TLR9 presence demonstrated by immunohistochemistry. Blocking TLR7/9 with a dual antagonist in vivo reduced neointimal thickening and foam cell accumulation 14 days after surgery by 65.6% (P=0.0079). Intima/media ratio was reduced by 64.5% and luminal stenosis by 62.8%. The TLR7/9 antagonist reduced the arterial wall inflammation, with reduced macrophage infiltration, decreased cytoplasmic high-mobility group box 1 expression, and altered serum interleukin-10 levels. Stimulation of cultured macrophages with TLR7 and TLR9 ligands enhanced tumor necrosis factor-α expression, which is decreased by TLR7/9 antagonist coadministration. Additionally, the antagonist abolished the TLR7/9-enhanced low-density lipoprotein uptake. The antagonist also reduced oxidized low-density lipoprotein-induced foam cell formation, most likely not via decreased influx but via increased efflux, because CD36 expression was unchanged whereas interleukin-10 levels were higher (36.1 ± 22.3 pg/mL versus 128.9 ± 6.6 pg/mL; P=0.008). CONCLUSIONS Blocking TLR7 and TLR9 reduced postinterventional vascular remodeling and foam cell accumulation indicating TLR7 and TLR9 as novel therapeutic targets.
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Affiliation(s)
- Jacco C Karper
- Einthoven Laboratory of Vascular Medicine, Department of Surgery, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, the Netherlands
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Dushkin MI. Macrophage/foam cell is an attribute of inflammation: Mechanisms of formation and functional role. BIOCHEMISTRY (MOSCOW) 2012; 77:327-38. [DOI: 10.1134/s0006297912040025] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Dynamics and regulation of lipid droplet formation in lipopolysaccharide (LPS)-stimulated microglia. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:607-17. [DOI: 10.1016/j.bbalip.2012.01.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 12/04/2011] [Accepted: 01/10/2012] [Indexed: 01/22/2023]
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Yuan Y, Li P, Ye J. Lipid homeostasis and the formation of macrophage-derived foam cells in atherosclerosis. Protein Cell 2012; 3:173-81. [PMID: 22447659 DOI: 10.1007/s13238-012-2025-6] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 02/04/2012] [Indexed: 01/18/2023] Open
Abstract
Atherosclerosis is a chronic, inflammatory disorder characterized by the deposition of excess lipids in the arterial intima. The formation of macrophage-derived foam cells in a plaque is a hallmark of the development of atherosclerosis. Lipid homeostasis, especially cholesterol homeostasis, plays a crucial role during the formation of foam cells. Recently, lipid droplet-associated proteins, including PAT and CIDE family proteins, have been shown to control the development of atherosclerosis by regulating the formation, growth, stabilization and functions of lipid droplets in macrophage-derived foam cells. This review focuses on the potential mechanisms of formation of macrophage-derived foam cells in atherosclerosis with particular emphasis on the role of lipid homeostasis and lipid droplet-associated proteins. Understanding the process of foam cell formation will aid in the future discovery of novel therapeutic interventions for atherosclerosis.
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Affiliation(s)
- Yuan Yuan
- Department of Pathology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China
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Xie X, Wang S, Xiao L, Zhang J, Wang J, Liu J, Shen X, He D, Zheng X, Zhai Y. DBZ blocks LPS-induced monocyte activation and foam cell formation via inhibiting nuclear factor-ĸB. Cell Physiol Biochem 2011; 28:649-62. [PMID: 22178877 DOI: 10.1159/000335760] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS It has been widely accepted that chronic inflammation plays important roles in the atherogenesis. Danshensu Bingpian Zhi (DBZ) is a novel synthetic compound derived from the traditional Chinese medicine (TCM) formula Fu Fang Dan Shen (FFDS), which is effective on atherosclerosis clinically. We hypothesized that DBZ possessed the anti-atherosclerosis potentials. Here, we examined the inhibitory effects of DBZ on LPS-induced monocyte activation and foam cell formation. METHODS The effects of DBZ were assessed on LPS-induced inflammatory factors expression in monocyte/macrophage. Activation of NF-κB and AP-1 was analyzed by luciferase reporter assay and signaling pathway of NF-κB was investigated to elucidate mechanisms underlying DBZ mediated anti-inflammatory activity. Effects of DBZ on macrophage lipid accumulation were evaluated in native LDL and LPS co-incubated macrophages. RESULTS DBZ inhibited LPS-induced inflammatory factors expression dose dependently in monocytes. DBZ inhibited NF-κB activation strongly and AP-1 slightly. DBZ suppressed the LPS-induced degradation of IκBα, thereby decreasing the translocation of p65 to nucleus. Furthermore, DBZ suppressed LPS-activated macrophages lipid accumulation, partly due to inhibiting the expression of LPS-induced aP2 and ADRP in macrophges. CONCLUSION These results demonstrate that DBZ has potentials on anti-atherosclerosis by suppressing monocyte activation and foam cell formation.
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Affiliation(s)
- Xinni Xie
- Key Laboratory for Cell Proliferation and Regulation Biology of State Education Ministry and College of Life Sciences, Beijing Normal University, Beijing, P.R. China
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Furuhashi M, Ishimura S, Ota H, Miura T. Lipid chaperones and metabolic inflammation. Int J Inflam 2011; 2011:642612. [PMID: 22121495 PMCID: PMC3206330 DOI: 10.4061/2011/642612] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 08/18/2011] [Indexed: 11/28/2022] Open
Abstract
Over the past decade, a large body of evidence has emerged demonstrating an integration of metabolic and immune response pathways. It is now clear that obesity and associated disorders such as insulin resistance and type 2 diabetes are associated with a metabolically driven, low-grade, chronic inflammatory state, referred to as “metaflammation.” Several inflammatory cytokines as well as lipids and metabolic stress pathways can activate metaflammation, which targets metabolically critical organs and tissues including adipocytes and macrophages to adversely affect systemic homeostasis. On the other hand, inside the cell, fatty acid-binding proteins (FABPs), a family of lipid chaperones, as well as endoplasmic reticulum (ER) stress, and reactive oxygen species derived from mitochondria play significant roles in promotion of metabolically triggered inflammation. Here, we discuss the molecular and cellular basis of the roles of FABPs, especially FABP4 and FABP5, in metaflammation and related diseases including obesity, diabetes, and atherosclerosis.
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Affiliation(s)
- Masato Furuhashi
- Second Department of Internal Medicine, Sapporo Medical University School of Medicine, S-1, W-16, Chuo-ku, Sapporo 060-8543, Japan
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Abstract
PURPOSE OF REVIEW The differentiation of macrophages into lipid-laden foam cells is central to the development of atherosclerosis. Traditionally, it has been assumed that the uptake of oxidized low-density lipoprotein by macrophage scavenger receptors is largely responsible for this process. However, in light of recent evidence that these mechanisms may not play as large a role as previously thought, alternative mechanisms of foam cell formation are now being explored. RECENT FINDINGS The stimulation of Toll-like receptor (TLR) signalling by bacterial molecules has been shown to promote the accumulation of lipid in macrophages in the form of intracellular inclusions termed 'lipid bodies'. Interactions between TLR-signalling pathways and the liver-X receptor and peroxisome proliferator-activated receptor-γ signalling pathways modulate the formation of lipid bodies in macrophages and thereby cellular accumulation of cholesterol and triglyceride. These pathways appear to involve TLR-mediated regulation of lipid-binding proteins, cellular cholesterol sensors, lipid-body-associated proteins and secreted autocrine factors, but are independent of scavenger receptor or lipoprotein oxidation-dependent pathways. SUMMARY TLR stimulation promotes the accumulation of lipid bodies in macrophages and consequently foam cell formation. The pathways responsible for these processes may constitute novel therapeutic targets for atherosclerosis.
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Affiliation(s)
- Giovanna Nicolaou
- Department of Cardiovascular Sciences, Glenfield General Hospital, University of Leicester, Leicester, UK
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Sims K, Haynes CA, Kelly S, Allegood JC, Wang E, Momin A, Leipelt M, Reichart D, Glass CK, Sullards MC, Merrill AH. Kdo2-lipid A, a TLR4-specific agonist, induces de novo sphingolipid biosynthesis in RAW264.7 macrophages, which is essential for induction of autophagy. J Biol Chem 2010; 285:38568-79. [PMID: 20876532 PMCID: PMC2992289 DOI: 10.1074/jbc.m110.170621] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Activation of RAW264.7 cells with a lipopolysaccharide specific for the TLR4 receptor, Kdo2-lipid A (KLA), causes a large increase in cellular sphingolipids, from 1.5 to 2.6 × 109 molecules per cell in 24 h, based on the sum of subspecies analyzed by “lipidomic” mass spectrometry. Thus, this study asked the following question. What is the cause of this increase and is there a cell function connected with it? The sphingolipids arise primarily from de novo biosynthesis based on [U-13C]palmitate labeling, inhibition by ISP1 (myriocin), and an apparent induction of many steps of the pathway (according to the distribution of metabolites and microarray analysis), with the exception of ceramide, which is also produced from pre-existing sources. Nonetheless, the activated RAW264.7 cells have a higher number of sphingolipids per cell because KLA inhibits cell division; thus, the cells are larger and contain increased numbers of membrane vacuoles termed autophagosomes, which were detected by the protein marker GFP-LC3. Indeed, de novo biosynthesis of sphingolipids performs an essential structural and/or signaling function in autophagy because autophagosome formation was eliminated by ISP1 in KLA-stimulated RAW264.7 cells (and mutation of serine palmitoyltransferase in CHO-LYB cells); furthermore, an anti-ceramide antibody co-localizes with autophagosomes in activated RAW264.7 cells versus the Golgi in unstimulated or ISP1-inhibited cells. These findings establish that KLA induces profound changes in sphingolipid metabolism and content in this macrophage-like cell line, apparently to produce sphingolipids that are necessary for formation of autophagosomes, which are thought to play important roles in the mechanisms of innate immunity.
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Affiliation(s)
- Kacee Sims
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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The expression and functions of toll-like receptors in atherosclerosis. Mediators Inflamm 2010; 2010:393946. [PMID: 20652007 PMCID: PMC2905957 DOI: 10.1155/2010/393946] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 04/07/2010] [Indexed: 12/16/2022] Open
Abstract
Inflammation drives atherosclerosis. Both immune and resident vascular cell types are involved in the development of atherosclerotic lesions. The phenotype and function of these cells are key in determining the development of lesions. Toll-like receptors are the most characterised innate immune receptors and are responsible for the recognition of exogenous conserved motifs on pathogens, and, potentially, some endogenous molecules. Both endogenous and exogenous TLR agonists may be present in atherosclerotic plaques. Engagement of toll-like receptors on immune and resident vascular cells can affect atherogenesis as signalling downstream of these receptors can elicit proinflammatory cytokine release, lipid uptake, and foam cell formation and activate cells of the adaptive immune system. In this paper, we will describe the expression of TLRs on immune and resident vascular cells, highlight the TLR ligands that may act through TLRs on these cells, and discuss the consequences of TLR activation in atherosclerosis.
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