1
|
Nery N, Setúbal S, Boeno C, Lopes J, Paloschi M, Pontes A, Luna K, Zuliani J. Bothrops erythromelas venom and its action on isolated murine macrophages. Toxicon 2020; 185:156-163. [DOI: 10.1016/j.toxicon.2020.07.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/15/2020] [Accepted: 07/18/2020] [Indexed: 11/25/2022]
|
2
|
Nouwen LV, Everts B. Pathogens MenTORing Macrophages and Dendritic Cells: Manipulation of mTOR and Cellular Metabolism to Promote Immune Escape. Cells 2020; 9:cells9010161. [PMID: 31936570 PMCID: PMC7017145 DOI: 10.3390/cells9010161] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/01/2020] [Accepted: 01/07/2020] [Indexed: 02/06/2023] Open
Abstract
Myeloid cells, including macrophages and dendritic cells, represent an important first line of defense against infections. Upon recognition of pathogens, these cells undergo a metabolic reprogramming that supports their activation and ability to respond to the invading pathogens. An important metabolic regulator of these cells is mammalian target of rapamycin (mTOR). During infection, pathogens use host metabolic pathways to scavenge host nutrients, as well as target metabolic pathways for subversion of the host immune response that together facilitate pathogen survival. Given the pivotal role of mTOR in controlling metabolism and DC and macrophage function, pathogens have evolved strategies to target this pathway to manipulate these cells. This review seeks to discuss the most recent insights into how pathogens target DC and macrophage metabolism to subvert potential deleterious immune responses against them, by focusing on the metabolic pathways that are known to regulate and to be regulated by mTOR signaling including amino acid, lipid and carbohydrate metabolism, and autophagy.
Collapse
|
3
|
Panettieri S, Paddibhatla I, Chou J, Rajwani R, Moore RS, Goncharuk T, John G, Govind S. Discovery of aspirin-triggered eicosanoid-like mediators in a Drosophila metainflammation blood tumor model. J Cell Sci 2019; 133:jcs.236141. [PMID: 31562189 DOI: 10.1242/jcs.236141] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/20/2019] [Indexed: 12/18/2022] Open
Abstract
Epidemiologic studies have linked the use of aspirin to a decline in chronic inflammation that underlies many human diseases, including some cancers. Aspirin reduces the levels of cyclooxygenase-mediated pro-inflammatory prostaglandins, promotes the production of pro-resolution molecules, and triggers the production of anti-inflammatory electrophilic mono-oxygenated (EFOX) lipid mediators. We investigated the effects of aspirin in fruit fly models of chronic inflammation. Ectopic Toll/NF-κB and JAK/STAT signaling in mutant D. melanogaster results in overproliferation of hematopoietic blood progenitors resulting in the formation of granuloma-like tumors. Ectopic JAK-STAT signaling also leads to metabolic inflammation. We report that aspirin-treated mutant flies experience reduction in metabolic inflammation, mitosis, ectopic immune signaling, and macrophage infiltration. Moreover, these flies synthesize 13-HODE, and aspirin triggers 13-oxoODE (13-EFOX-L2) production. Providing the precursor of 13-HODE, linoleic acid, or performing targeted knockdown of the transcription factor STAT in inflammatory blood cells, boosts 13-EFOX-L2 levels while decreasing metabolic inflammation. Thus, hematopoietic cells regulate metabolic inflammation in flies, and their effects can be reversed by pharmaceutical or dietary intervention, suggesting deep phylogenetic conservation in the ability of animals to resolve inflammation and repair tissue damage. These findings can help identify novel treatment targets in humans.
Collapse
Affiliation(s)
- Silvio Panettieri
- Department of Chemistry & Biochemistry, The City College of New York, New York, NY 10031, USA.,PhD Program in Chemistry, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA
| | - Indira Paddibhatla
- PhD Program in Biology, Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA.,Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Jennifer Chou
- Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Roma Rajwani
- Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Rebecca S Moore
- Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Tamara Goncharuk
- Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - George John
- Department of Chemistry & Biochemistry, The City College of New York, New York, NY 10031, USA .,PhD Program in Chemistry, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA
| | - Shubha Govind
- Biology Department, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA .,PhD Programs in Biology & Biochemistry, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA
| |
Collapse
|
4
|
Bose D, Banerjee S, Chatterjee N, Das S, Saha M, Saha KD. Inhibition of TGF-β induced lipid droplets switches M2 macrophages to M1 phenotype. Toxicol In Vitro 2019; 58:207-214. [DOI: 10.1016/j.tiv.2019.03.037] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/12/2019] [Accepted: 03/27/2019] [Indexed: 01/17/2023]
|
5
|
Abstract
Lipid droplets (LDs) are lipid-carrying multifunctional organelles, which might also interact with pathogens and influence the host immune response. However, the exact nature of these interactions remains currently unexplored. Here we show that systemic infection of Drosophila adult flies with non-pathogenic Escherichia coli, the extracellular bacterial pathogen Photorhabdus luminescens or the facultative intracellular pathogen Photorhabdus asymbiotica results in intestinal steatosis marked by lipid accumulation in the midgut. Accumulation of LDs in the midgut also correlates with increased whole-body lipid levels characterized by increased expression of genes regulating lipogenesis. The lipid-enriched midgut further displays reduced expression of the enteroendocrine-secreted hormone, Tachykinin. The observed lipid accumulation requires the Gram-negative cell wall pattern recognition molecule, PGRP-LC, but not PGRP-LE, for the humoral immune response. Altogether, our findings indicate that Drosophila LDs are inducible organelles, which can serve as markers for inflammation and, depending on the nature of the challenge, they can dictate the outcome of the infection. Summary: Lipid droplets are inducible organelles, act as inflammatory markers and, depending on the nature of challenge, can dictate the outcome of the infection.
Collapse
Affiliation(s)
- Sneh Harsh
- Department of Biological Sciences, Institute for Biomedical Sciences, The George Washington University, Washington DC 20052, USA
| | - Christa Heryanto
- Department of Biological Sciences, Institute for Biomedical Sciences, The George Washington University, Washington DC 20052, USA
| | - Ioannis Eleftherianos
- Department of Biological Sciences, Institute for Biomedical Sciences, The George Washington University, Washington DC 20052, USA
| |
Collapse
|
6
|
Cruz ALS, Carrossini N, Teixeira LK, Ribeiro-Pinto LF, Bozza PT, Viola JPB. Cell Cycle Progression Regulates Biogenesis and Cellular Localization of Lipid Droplets. Mol Cell Biol 2019; 39:e00374-18. [PMID: 30782775 DOI: 10.1128/MCB.00374-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 01/25/2019] [Indexed: 12/19/2022] Open
Abstract
Intracellular lipid accumulation has been associated with a poor prognosis in cancer. We have previously reported the involvement of lipid droplets in cell proliferation in colon cancer cells, suggesting a role for these organelles in cancer development. Intracellular lipid accumulation has been associated with a poor prognosis in cancer. We have previously reported the involvement of lipid droplets in cell proliferation in colon cancer cells, suggesting a role for these organelles in cancer development. In this study, we evaluate the role of lipid droplets in cell cycle regulation and cellular transformation. Cell cycle synchronization of NIH 3T3 cells revealed increased numbers and dispersed distribution of lipid droplets specifically during S phase. Also, the transformed cell lineage NIH 3T3-H-rasV12 showed an accumulation of both lipid droplets and PLIN2 protein above the levels in NIH 3T3 cells. PLIN2 gene overexpression, however, was not able to induce NIH 3T3 cell transformation, disproving the hypothesis that PLIN2 is an oncogene. Furthermore, positive PLIN2 staining was strongly associated with highly proliferative Ki-67-positive areas in human colon adenocarcinoma tissue samples. Taken together, these results indicate that cell cycle progression is associated with tight regulation of lipid droplets, a process that is altered in transformed cells, suggesting the existence of a mechanism that connects cell cycle progression and cell proliferation with lipid accumulation.
Collapse
|
7
|
Jensen CF, Bartels ED, Braunstein TH, Nielsen LB, Holstein‐Rathlou N, Axelsen LN, Nielsen MS. Acute intramyocardial lipid accumulation in rats does not slow cardiac conduction per se. Physiol Rep 2019; 7:e14049. [PMID: 30968589 PMCID: PMC6456446 DOI: 10.14814/phy2.14049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/12/2019] [Accepted: 03/12/2019] [Indexed: 01/14/2023] Open
Abstract
Diabetic patients suffer from both cardiac lipid accumulation and an increased risk of arrhythmias and sudden cardiac death. This correlation suggests a link between diabetes induced cardiac steatosis and electrical abnormalities, however, the underlying mechanism remains unknown. We previously showed that cardiac conduction velocity slows in Zucker diabetic fatty rats and in fructose-fat fed rats, models that both exhibit prominent cardiac steatosis. The aim of this study was to investigate whether acute cardiac lipid accumulation reduces conduction velocity per se. Cardiac lipid accumulation was induced acutely by perfusing isolated rat hearts with palmitate-glucose buffer, or subacutely by fasting rats overnight. Subsequently, longitudinal cardiac conduction velocity was measured in right ventricular tissue strips, and intramyocardial triglyceride and lipid droplet content was determined by thin layer chromatography and BODIPY staining, respectively. Perfusion with palmitate-glucose buffer significantly increased intramyocardial triglyceride levels compared to perfusion with glucose (2.16 ± 0.17 (n = 10) vs. 0.92 ± 0.33 nmol/mg WW (n = 9), P < 0.01), but the number of lipid droplets was very low in both groups. Fasting of rats, however, resulted in both significantly elevated intramyocardial triglyceride levels compared to fed rats (3.27 ± 0.43 (n = 10) vs. 1.45 ± 0.24 nmol/mg WW (n = 10)), as well as a larger volume of lipid droplets (0.60 ± 0.13 (n = 10) vs. 0.21 ± 0.06% (n = 10), P < 0.05). There was no significant difference in longitudinal conduction velocity between palmitate-glucose perfused and control hearts (0.77 ± 0.025 (n = 10) vs. 0.75 m/sec ± 0.029 (n = 9)), or between fed and fasted rats (0.75 ± 0.042 m/sec (n = 10) vs. 0.79 ± 0.047 (n = 10)). In conclusion, intramyocardial lipid accumulation does not slow cardiac longitudinal conduction velocity per se. This is true for both increased intramyocardial triglyceride content, induced by palmitate-glucose perfusion, and increased intramyocardial triglyceride and lipid droplet content, generated by fasting.
Collapse
Affiliation(s)
- Christa F. Jensen
- Department of Biomedical SciencesFaculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Emil D. Bartels
- Department of Clinical BiochemistryCopenhagen University Hospital RigshospitaletCopenhagenDenmark
| | - Thomas H. Braunstein
- Department of Biomedical SciencesFaculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Lars B. Nielsen
- Department of Clinical BiochemistryCopenhagen University Hospital RigshospitaletCopenhagenDenmark
| | | | - Lene N. Axelsen
- Department of Biomedical SciencesFaculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Morten Schak Nielsen
- Department of Biomedical SciencesFaculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| |
Collapse
|
8
|
Lin CH, Liao LY, Yang TY, Chang YJ, Tung CW, Hsu SL, Hsueh CM. Microglia-Derived Adiposomes are Potential Targets for the Treatment of Ischemic Stroke. Cell Mol Neurobiol 2019; 39:591-604. [PMID: 30852719 DOI: 10.1007/s10571-019-00665-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 02/19/2019] [Indexed: 12/28/2022]
Abstract
It is known that cerebral ischemia can cause brain inflammation and adiposome can serve as a depot of inflammatory mediators. In the study, the pro-inflammatory and pro-death role of adiposome in ischemic microglia and ischemic brain was newly investigated. The contribution of PPARγ to adiposome formation was also evaluated for the first time in ischemic microglia. Focal cerebral ischemia/reperfusion (I/R) animal model and the in vitro glucose-oxygen-serum deprivation (GOSD) cell model were both applied in the study. GOSD- or I/R-induced adiposome formation, inflammatory activity, cell death of microglia, and brain infarction were, respectively, determined, in the absence or presence of NS-398 (adiposome inhibitor) or GW9662 (PPARγ antagonist). GOSD-increased adiposome formation played a critical role in stimulating the inflammatory activity (production of TNF-α and IL-1β) and cell death of microglia. Similar results were also found in ischemic brain tissues. GOSD-induced PPARγ partially contributed to the increase of adiposomes and adiposome-mediated inflammatory responses of microglia. Blockade of adiposome formation with NS-398 or GW9662 significantly reduced not only the inflammatory activity and death rate of GOSD-treated microglia but also the brain infarct volume and motor function deficit of ischemic rats. The pathological role of microglia-derived adiposome in cerebral ischemia has been confirmed and attributed to its pro-inflammatory and/or pro-death effect upon ischemic brain cells and tissues. Adiposome and its upstream regulator PPARγ were therefore as potential targets for the treatment of ischemic stroke. Therapeutic values of NS-398 and GW9662 have been suggested.
Collapse
Affiliation(s)
- Chi-Hsin Lin
- Department of Medical Research, MacKay Memorial Hospital, New Taipei City, Taiwan.,Department of Bioscience Technology, Chung Yuan Christian University, Taoyuan City, Taiwan
| | - Li-Ya Liao
- Department of Life Sciences, National Chung Hsing University, 145, Xingda Road, Taichung, 402, Taiwan, ROC
| | - Tsung-Ying Yang
- Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yi-Jyun Chang
- Department of Life Sciences, National Chung Hsing University, 145, Xingda Road, Taichung, 402, Taiwan, ROC
| | - Chia-Wen Tung
- Department of Life Sciences, National Chung Hsing University, 145, Xingda Road, Taichung, 402, Taiwan, ROC
| | - Shih-Lan Hsu
- Department of Life Sciences, National Chung Hsing University, 145, Xingda Road, Taichung, 402, Taiwan, ROC
| | - Chi-Mei Hsueh
- Department of Life Sciences, National Chung Hsing University, 145, Xingda Road, Taichung, 402, Taiwan, ROC. .,The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC.
| |
Collapse
|
9
|
Abreu SC, Lopes-Pacheco M, da Silva AL, Xisto DG, de Oliveira TB, Kitoko JZ, de Castro LL, Amorim NR, Martins V, Silva LHA, Gonçalves-de-Albuquerque CF, de Castro Faria-Neto HC, Olsen PC, Weiss DJ, Morales MM, Diaz BL, Rocco PRM. Eicosapentaenoic Acid Enhances the Effects of Mesenchymal Stromal Cell Therapy in Experimental Allergic Asthma. Front Immunol 2018; 9:1147. [PMID: 29881388 PMCID: PMC5976792 DOI: 10.3389/fimmu.2018.01147] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/07/2018] [Indexed: 12/19/2022] Open
Abstract
Asthma is characterized by chronic lung inflammation and airway hyperresponsiveness. Despite recent advances in the understanding of its pathophysiology, asthma remains a major public health problem and, at present, there are no effective interventions capable of reversing airway remodeling. Mesenchymal stromal cell (MSC)-based therapy mitigates lung inflammation in experimental allergic asthma; however, its ability to reduce airway remodeling is limited. We aimed to investigate whether pre-treatment with eicosapentaenoic acid (EPA) potentiates the therapeutic properties of MSCs in experimental allergic asthma. Seventy-two C57BL/6 mice were used. House dust mite (HDM) extract was intranasally administered to induce severe allergic asthma in mice. Unstimulated or EPA-stimulated MSCs were administered intratracheally 24 h after final HDM challenge. Lung mechanics, histology, protein levels of biomarkers, and cellularity in bronchoalveolar lavage fluid (BALF), thymus, lymph nodes, and bone marrow were analyzed. Furthermore, the effects of EPA on lipid body formation and secretion of resolvin-D1 (RvD1), prostaglandin E2 (PGE2), interleukin (IL)-10, and transforming growth factor (TGF)-β1 by MSCs were evaluated in vitro. EPA-stimulated MSCs, compared to unstimulated MSCs, yielded greater therapeutic effects by further reducing bronchoconstriction, alveolar collapse, total cell counts (in BALF, bone marrow, and lymph nodes), and collagen fiber content in airways, while increasing IL-10 levels in BALF and M2 macrophage counts in lungs. In conclusion, EPA potentiated MSC-based therapy in experimental allergic asthma, leading to increased secretion of pro-resolution and anti-inflammatory mediators (RvD1, PGE2, IL-10, and TGF-β), modulation of macrophages toward an anti-inflammatory phenotype, and reduction in the remodeling process. Taken together, these modifications may explain the greater improvement in lung mechanics obtained. This may be a promising novel strategy to potentiate MSCs effects.
Collapse
Affiliation(s)
- Soraia Carvalho Abreu
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, United States
| | - Miquéias Lopes-Pacheco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adriana Lopes da Silva
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Debora Gonçalves Xisto
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tainá Batista de Oliveira
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jamil Zola Kitoko
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratory of Clinical Bacteriology and Immunology, School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lígia Lins de Castro
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Natália Recardo Amorim
- Laboratory of Inflammation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vanessa Martins
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luisa H A Silva
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cassiano Felippe Gonçalves-de-Albuquerque
- Biomedical Institute, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratory of Immunopharmacology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Priscilla Christina Olsen
- Laboratory of Clinical Bacteriology and Immunology, School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Daniel Jay Weiss
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, United States
| | - Marcelo Marcos Morales
- Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,National Institute of Science and Technology for Regenerative Medicine, Rio de Janeiro, Brazil
| | - Bruno Lourenço Diaz
- Laboratory of Inflammation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patricia Rieken Macêdo Rocco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,National Institute of Science and Technology for Regenerative Medicine, Rio de Janeiro, Brazil
| |
Collapse
|
10
|
Vallochi AL, Teixeira L, Oliveira KDS, Maya-Monteiro CM, Bozza PT. Lipid Droplet, a Key Player in Host-Parasite Interactions. Front Immunol 2018; 9:1022. [PMID: 29875768 PMCID: PMC5974170 DOI: 10.3389/fimmu.2018.01022] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/24/2018] [Indexed: 12/18/2022] Open
Abstract
Lipid droplets (lipid bodies, LDs) are dynamic organelles that have important roles in regulating lipid metabolism, energy homeostasis, cell signaling, membrane trafficking, and inflammation. LD biogenesis, composition, and functions are highly regulated and may vary according to the stimuli, cell type, activation state, and inflammatory environment. Increased cytoplasmic LDs are frequently observed in leukocytes and other cells in a number of infectious diseases. Accumulating evidence reveals LDs participation in fundamental mechanisms of host-pathogen interactions, including cell signaling and immunity. LDs are sources of eicosanoid production, and may participate in different aspects of innate signaling and antigen presentation. In addition, intracellular pathogens evolved mechanisms to subvert host metabolism and may use host LDs, as ways of immune evasion and nutrients source. Here, we review mechanisms of LDs biogenesis and their contributions to the infection progress, and discuss the latest discoveries on mechanisms and pathways involving LDs roles as regulators of the immune response to protozoan infection.
Collapse
Affiliation(s)
- Adriana Lima Vallochi
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | | | | | | | - Patricia T. Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| |
Collapse
|
11
|
de Almeida PE, Toledo DAM, Rodrigues GSC, D'Avila H. Lipid Bodies as Sites of Prostaglandin E2 Synthesis During Chagas Disease: Impact in the Parasite Escape Mechanism. Front Microbiol 2018; 9:499. [PMID: 29616011 PMCID: PMC5869919 DOI: 10.3389/fmicb.2018.00499] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 03/05/2018] [Indexed: 12/22/2022] Open
Abstract
During Chagas disease, the Trypanosoma cruzi can induce some changes in the host cells in order to escape or manipulate the host immune response. The modulation of the lipid metabolism in the host phagocytes or in the parasite itself is one feature that has been observed. The goal of this mini review is to discuss the mechanisms that regulate intracellular lipid body (LB) biogenesis in the course of this parasite infection and their meaning to the pathophysiology of the disease. The interaction host–parasite induces LB (or lipid droplet) formation in a Toll-like receptor 2-dependent mechanism in macrophages and is enhanced by apoptotic cell uptake. Simultaneously, there is a lipid accumulation in the parasite due to the incorporation of host fatty acids. The increase in the LB accumulation during infection is correlated with an increase in the synthesis of PGE2 within the host cells and the parasite LBs. Moreover, the treatment with fatty acid synthase inhibitor C75 or non-steroidal anti-inflammatory drugs such as NS-398 and aspirin inhibited the LB biogenesis and also induced the down modulation of the eicosanoid production and the parasite replication. These findings show that LBs are organelles up modulated during the course of infection. Furthermore, the biogenesis of the LB is involved in the lipid mediator generation by both the macrophages and the parasite triggering escape mechanisms.
Collapse
Affiliation(s)
- Patrícia E de Almeida
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | | | - Gabriel S C Rodrigues
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Heloisa D'Avila
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| |
Collapse
|
12
|
Mulye M, Zapata B, Gilk SD. Altering lipid droplet homeostasis affects Coxiella burnetii intracellular growth. PLoS One 2018; 13:e0192215. [PMID: 29390006 DOI: 10.1371/journal.pone.0192215] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 01/19/2018] [Indexed: 12/14/2022] Open
Abstract
Coxiella burnetii is an obligate intracellular bacterial pathogen and a causative agent of culture-negative endocarditis. While C. burnetii initially infects alveolar macrophages, it has also been found in lipid droplet (LD)-containing foamy macrophages in the cardiac valves of endocarditis patients. In addition, transcriptional studies of C. burnetii-infected macrophages reported differential regulation of the LD coat protein-encoding gene perilipin 2 (plin-2). To further investigate the relationship between LDs and C. burnetii, we compared LD numbers using fluorescence microscopy in mock-infected and C. burnetii-infected alveolar macrophages. On average, C. burnetii-infected macrophages contained twice as many LDs as mock-infected macrophages. LD numbers increased as early as 24 hours post-infection, an effect reversed by blocking C. burnetii protein synthesis. The observed LD accumulation was dependent on the C. burnetii Type 4B Secretion System (T4BSS), a major virulence factor that manipulates host cellular processes by secreting bacterial effector proteins into the host cell cytoplasm. To determine the importance of LDs during C. burnetii infection, we manipulated LD homeostasis and assessed C. burnetii intracellular growth. Surprisingly, blocking LD formation with the pharmacological inhibitors triacsin C or T863, or knocking out acyl-CoA transferase-1 (acat-1) in alveolar macrophages, increased C. burnetii growth at least 2-fold. Conversely, preventing LD lipolysis by inhibiting adipose triglyceride lipase (ATGL) with atglistatin almost completely blocked bacterial growth, suggesting LD breakdown is essential for C. burnetii. Together these data suggest that maintenance of LD homeostasis, possibly via the C. burnetii T4BSS, is critical for bacterial growth.
Collapse
|
13
|
Arcanjo AF, Nunes MP, Silva-Junior EB, Leandro M, Rocha JDBD, Morrot A, Decote-Ricardo D, Freire-de-Lima CG. B-1 cells modulate the murine macrophage response to Leishmania major infection. World J Biol Chem 2017; 8:151-162. [PMID: 28588758 PMCID: PMC5439166 DOI: 10.4331/wjbc.v8.i2.151] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 12/16/2016] [Accepted: 03/17/2017] [Indexed: 02/05/2023] Open
Abstract
AIM To investigate the modulatory effect of B-1 cells on murine peritoneal macrophages infected with Leishmania major (L. major) in vitro.
METHODS Peritoneal macrophages obtained from BALB/c and BALB/c XID mice were infected with L. major and cultured in the presence or absence of B-1 cells obtained from wild-type BALB/c mice. Intracellular amastigotes were counted, and interleukin-10 (IL-10) production was quantified in the cellular supernatants using an enzyme-linked immunosorbent assay. The levels of the lipid mediator prostaglandin E2 (PGE2) were determined using a PGE2 enzyme immunoassay kit (Cayman Chemical, Ann Arbor, MI), and the number of lipid bodies was quantified in the cytoplasm of infected macrophages in the presence and absence of B-1 cells. Culturing the cells with selective PGE2-neutralizing drugs inhibited PGE2 production and confirmed the role of this lipid mediator in IL-10 production. In contrast, we demonstrated that B-1 cells derived from IL-10 KO mice did not favor the intracellular growth of L. major.
RESULTS We report that B-1 cells promote the growth of L. major amastigotes inside peritoneal murine macrophages. We demonstrated that the modulatory effect was independent of physical contact between the cells, suggesting that soluble factor(s) were released into the cultures. We demonstrated in our co-culture system that B-1 cells trigger IL-10 production by L. major-infected macrophages. Furthermore, the increased secretion of IL-10 was attributed to the presence of the lipid mediator PGE2 in supernatants of L. major-infected macrophages. The presence of B-1 cells also favors the production of lipid bodies by infected macrophages. In contrast, we failed to obtain the same effect on parasite replication inside L. major-infected macrophages when the B-1 cells were isolated from IL-10 knockout mice.
CONCLUSION Our results show that elevated levels of PGE2 and IL-10 produced by B-1 cells increase L. major growth, as indicated by the number of parasites in cell cultures.
Collapse
|
14
|
Toledo DA, Roque NR, Teixeira L, Milán-Garcés EA, Carneiro AB, Almeida MR, Andrade GF, Martins JS, Pinho RR, Freire-de-Lima CG, Bozza PT, D'Avila H, Melo RC. Lipid Body Organelles within the Parasite Trypanosoma cruzi: A Role for Intracellular Arachidonic Acid Metabolism. PLoS One 2016; 11:e0160433. [PMID: 27490663 DOI: 10.1371/journal.pone.0160433] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 07/19/2016] [Indexed: 12/19/2022] Open
Abstract
Most eukaryotic cells contain varying amounts of cytosolic lipidic inclusions termed lipid bodies (LBs) or lipid droplets (LDs). In mammalian cells, such as macrophages, these lipid-rich organelles are formed in response to host-pathogen interaction during infectious diseases and are sites for biosynthesis of arachidonic acid (AA)-derived inflammatory mediators (eicosanoids). Less clear are the functions of LBs in pathogenic lower eukaryotes. In this study, we demonstrated that LBs, visualized by light microscopy with different probes and transmission electron microscopy (TEM), are produced in trypomastigote forms of the parasite Trypanosoma cruzi, the causal agent of Chagas' disease, after both host interaction and exogenous AA stimulation. Quantitative TEM revealed that LBs from amastigotes, the intracellular forms of the parasite, growing in vivo have increased size and electron-density compared to LBs from amastigotes living in vitro. AA-stimulated trypomastigotes released high amounts of prostaglandin E2 (PGE2) and showed PGE2 synthase expression. Raman spectroscopy demonstrated increased unsaturated lipid content and AA incorporation in stimulated parasites. Moreover, both Raman and MALDI mass spectroscopy revealed increased AA content in LBs purified from AA-stimulated parasites compared to LBs from unstimulated group. By using a specific technique for eicosanoid detection, we immunolocalized PGE2 within LBs from AA-stimulated trypomastigotes. Altogether, our findings demonstrate that LBs from the parasite Trypanosoma cruzi are not just lipid storage inclusions but dynamic organelles, able to respond to host interaction and inflammatory events and involved in the AA metabolism. Acting as sources of PGE2, a potent immunomodulatory lipid mediator that inhibits many aspects of innate and adaptive immunity, newly-formed parasite LBs may be implicated with the pathogen survival in its host.
Collapse
|
15
|
Heller S, Cable C, Penrose H, Makboul R, Biswas D, Cabe M, Crawford SE, Savkovic SD. Intestinal inflammation requires FOXO3 and prostaglandin E2-dependent lipogenesis and elevated lipid droplets. Am J Physiol Gastrointest Liver Physiol 2016; 310:G844-54. [PMID: 26968210 PMCID: PMC4895869 DOI: 10.1152/ajpgi.00407.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 03/07/2016] [Indexed: 01/31/2023]
Abstract
Intestinal inflammation has been recently characterized by the dysregulation of lipids as metabolic and energy sources, revealing a novel feature of its pathophysiology. Because intracellular lipids, stored in dynamic lipid droplets (LDs), provide energy for cellular needs, we investigated whether they play a role in intestinal inflammation. In the inflamed intestine of mice, elevated LDs were found in colonic and infiltrating immune cells as shown by staining for the LD coat protein PLIN2 and for lipids with BODIPY. In colonic cells, TNF stimulated LD increases by receptor signaling rely on phosphatidylinositol 3-kinase activation. Downstream, TNF triggered a negative regulatory loop between LDs and the transcription factor FOXO3. This was shown in the colon of Foxo3-deficient mice, where elevation in PLIN2 and lipids were further facilitated by inflammation and were more prominent relative to wild-type, whereas, in colonic cells, inhibition of lipogenesis blocked the TNF-mediated loss of FOXO3. Furthermore, blockade of PGE2 synthesis abrogated TNF-stimulated increases in LDs and FOXO3 inactivation. We found in colonic tissue of Foxo3-deficient mice higher levels of cyclooxygenase-2, a mediator of prostaglandin E2 (PGE2) synthesis, supporting involvement of PGE2 in the LD-FOXO3 regulatory loop. Ultimately, TNF-stimulated lipogenesis leading to elevated LDs facilitated NF-κB-mediated increases in IL-8 protein, which is associated with the surface of LDs found in the lumina of the endoplasmic reticulum and Golgi apparatus. This novel immunometabolic mechanism of colonic inflammation involving elevated LDs could provide opportunities for new treatment options.
Collapse
Affiliation(s)
- Sandra Heller
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| | - Chloe Cable
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| | - Harrison Penrose
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| | - Rania Makboul
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana; ,3Pathology Department, Assiut University, Assiut, Egypt
| | - Debjani Biswas
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| | - Maleen Cabe
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| | - Susan E. Crawford
- 2Department of Pathology, St. Louis University, St Louis, Missouri; and
| | - Suzana D. Savkovic
- 1Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, Louisiana;
| |
Collapse
|
16
|
Toledo DAM, D'Avila H, Melo RCN. Host Lipid Bodies as Platforms for Intracellular Survival of Protozoan Parasites. Front Immunol 2016; 7:174. [PMID: 27199996 PMCID: PMC4853369 DOI: 10.3389/fimmu.2016.00174] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 04/19/2016] [Indexed: 12/31/2022] Open
Abstract
Pathogens induce several changes in the host cell signaling and trafficking mechanisms in order to evade and manipulate the immune response. One prominent pathogen-mediated change is the formation of lipid-rich organelles, termed lipid bodies (LBs) or lipid droplets, in the host cell cytoplasm. Protozoan parasites, which contribute expressively to the burden of infectious diseases worldwide, are able to induce LB genesis in non-immune and immune cells, mainly macrophages, key players in the initial resistance to the infection. Under host–parasite interaction, LBs not only accumulate in the host cytoplasm but also relocate around and move into parasitophorous vacuoles. There is increasing evidence that protozoan parasites may target host-derived LBs either for gaining nutrients or for escaping the host immune response. Newly formed, parasite-induced LBs may serve as lipid sources for parasite growth and also produce inflammatory mediators that potentially act in the host immune response deactivation. In this mini review, we summarize current knowledge on the formation and role of host LBs as sites exploited by intracellular protozoan parasites as a strategy to maintain their own survival.
Collapse
Affiliation(s)
- Daniel A M Toledo
- Laboratory of Cellular Biology, Department of Biology, Institute of Biological Sciences (ICB), Federal University of Juiz de Fora (UFJF) , Juiz de Fora, Minas Gerais , Brazil
| | - Heloísa D'Avila
- Laboratory of Cellular Biology, Department of Biology, Institute of Biological Sciences (ICB), Federal University of Juiz de Fora (UFJF) , Juiz de Fora, Minas Gerais , Brazil
| | - Rossana C N Melo
- Laboratory of Cellular Biology, Department of Biology, Institute of Biological Sciences (ICB), Federal University of Juiz de Fora (UFJF) , Juiz de Fora, Minas Gerais , Brazil
| |
Collapse
|
17
|
Guedes-da-Silva FH, Batista DG, Meuser MB, Demarque KC, Fulco TO, Araújo JS, Da Silva PB, Da Silva CF, Patrick DA, Bakunova SM, Bakunov SA, Tidwell RR, Oliveira GM, Britto C, Moreira OC, Soeiro MN. In Vitro and In Vivo Trypanosomicidal Action of Novel Arylimidamides against Trypanosoma cruzi. Antimicrob Agents Chemother 2016; 60:2425-34. [PMID: 26856830 DOI: 10.1128/AAC.01667-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 02/02/2016] [Indexed: 01/07/2023] Open
Abstract
Arylimidamides (AIAs) have been shown to have considerable biological activity against intracellular pathogens, includingTrypanosoma cruzi, which causes Chagas disease. In the present study, the activities of 12 novel bis-AIAs and 2 mono-AIAs against different strains ofT. cruziin vitroandin vivowere analyzed. The most active wasm-terphenyl bis-AIA (35DAP073), which had a 50% effective concentration (EC50) of 0.5 μM for trypomastigotes (Y strain), which made it 26-fold more effective than benznidazole (Bz; 13 μM). It was also active against the Colombiana strain (EC50= 3.8 μM). Analysis of the activity against intracellular forms of the Tulahuen strain showed that this bis-AIA (EC50= 0.04 μM) was about 100-fold more active than Bz (2 μM). The trypanocidal effect was dissociated from the ability to trigger intracellular lipid bodies within host cells, detected by oil red labeling. Both an active compound (35DAP073) and an inactive compound (26SMB060) displayed similar activation profiles. Due to their high selectivity indexes, two AIAs (35DAP073 and 35DAP081) were moved toin vivostudies, but because of the results of acute toxicity assays, 35DAP081 was excluded from the subsequent tests. The findings obtained with 35DAP073 treatment of infections caused by the Y strain revealed that 2 days of therapy induced a dose-dependent action, leading to 96 to 46% reductions in the level of parasitemia. However, the administration of 10 daily doses in animals infected with the Colombiana strain resulted in toxicity, preventing longer periods of treatment. The activity of the combination of 0.5 mg/kg of body weight/day 35DAP073 with 100 mg/kg/day Bz for 10 consecutive days was then assayed. Treatment with the combination resulted in the suppression of parasitemia, the elimination of neurological toxic effects, and survival of 100% of the animals. Quantitative PCR showed a considerable reduction in the parasite load (60%) compared to that achieved with Bz or the amidine alone. Our results support further investigations of this class with the aim of developing novel alternatives for the treatment of Chagas disease.
Collapse
|
18
|
WELLER PETERF. LEUKOCYTE LIPID BODIES - STRUCTURE AND FUNCTION AS "EICOSASOMES". Trans Am Clin Climatol Assoc 2016; 127:328-340. [PMID: 28066068 PMCID: PMC5216467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Lipid bodies are cytoplasmic inclusions that develop within leukocytes, including eosinophils and neutrophils, associated with inflammation. Our investigations of the formation and function of lipid bodies have revealed that they are distinct, inducible endoplasmic reticulum-derived, membrane- and ribosome-containing organelles with diverse functional roles in inflammatory responses of leukocytes. Leukocyte lipid bodies contain all enzymes required for synthesizing cyclo-oxygenase- and lipoxygenase-derived eicosanoids. Lipid body formation, rapidly inducible in vitro and in vivo by specific intracellular signaling pathways, enhances leukocyte formation of cyclo-oxygenase- and lipoxygenase-derived eicosanoids. Lipid bodies are discrete sites of eicosanoid synthesis, as documented for immunolocalized leukotriene C4, leukotriene B4, and prostaglandin E2. Lipid body-derived eicosanoids function as both paracrine and intracrine mediators of inflammation. Based on combined proteomic and ultrastructural studies, leukocyte lipid bodies are complex organelles with internal membranes and ribosomes. Structurally and functionally leukocyte lipid bodes are distinct from lipid droplets in adipocytes.
Collapse
|
19
|
Ribnicky DM, Poulev A, Raskin I. The Determination of Salicylates in Gaultheria procumbens for Use as a Natural Aspirin Alternative. ACTA ACUST UNITED AC 2015; 4:39-52. [DOI: 10.1300/j133v04n01_05] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
20
|
Schlager S, Goeritzer M, Jandl K, Frei R, Vujic N, Kolb D, Strohmaier H, Dorow J, Eichmann TO, Rosenberger A, Wölfler A, Lass A, Kershaw EE, Ceglarek U, Dichlberger A, Heinemann A, Kratky D. Adipose triglyceride lipase acts on neutrophil lipid droplets to regulate substrate availability for lipid mediator synthesis. J Leukoc Biol 2015; 98:837-50. [PMID: 26109679 PMCID: PMC4594763 DOI: 10.1189/jlb.3a0515-206r] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 06/09/2015] [Indexed: 01/18/2023] Open
Abstract
Lipid mediator release depends on the hydrolysis of triglyceride-rich lipid droplets mediated by ATGL, a potent regulator of inflammatory diseases. In humans, mutations in ATGL lead to TG accumulation in LDs of most tissues and cells, including peripheral blood leukocytes. This pathologic condition is called Jordans’ anomaly, in which functional consequences have not been investigated. In the present study, we tested the hypothesis that ATGL plays a role in leukocyte LD metabolism and immune cell function. Similar to humans with loss-of-function mutations in ATGL, we found that global and myeloid-specific Atgl−/− mice exhibit Jordans’ anomaly with increased abundance of intracellular TG-rich LDs in neutrophil granulocytes. In a model of inflammatory peritonitis, lipid accumulation was also observed in monocytes and macrophages but not in eosinophils or lymphocytes. Neutrophils from Atgl−/− mice showed enhanced immune responses in vitro, which were more prominent in cells from global compared with myeloid-specific Atgl−/− mice. Mechanistically, ATGL−/− as well as pharmacological inhibition of ATGL led to an impaired release of lipid mediators from neutrophils. These findings demonstrate that the release of lipid mediators is dependent on the liberation of precursor molecules from the TG-rich pool of LDs by ATGL. Our data provide mechanistic insights into Jordans’ anomaly in neutrophils and suggest that ATGL is a potent regulator of immune cell function and inflammatory diseases.
Collapse
Affiliation(s)
- Stefanie Schlager
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Madeleine Goeritzer
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Katharina Jandl
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Robert Frei
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Nemanja Vujic
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Dagmar Kolb
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Heimo Strohmaier
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Juliane Dorow
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Thomas O Eichmann
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Angelika Rosenberger
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Albert Wölfler
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Achim Lass
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Erin E Kershaw
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Uta Ceglarek
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Andrea Dichlberger
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Akos Heinemann
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Dagmar Kratky
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| |
Collapse
|
21
|
Urrutia RA, Kalinec F. Biology and pathobiology of lipid droplets and their potential role in the protection of the organ of Corti. Hear Res 2015; 330:26-38. [PMID: 25987503 DOI: 10.1016/j.heares.2015.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 12/20/2022]
Abstract
The current review article seeks to extend our understanding on the role of lipid droplets within the organ of Corti. In addition to presenting an overview of the current information about the origin, structure and function of lipid droplets we draw inferences from the collective body of knowledge about this cellular organelle to build a conceptual framework to better understanding their role in auditory function. This conceptual model considers that lipid droplets play a significant role in the synthesis, storage, and release of lipids and proteins for energetic use and/or modulating cell signaling pathways. We describe the role and mechanism by which LD play a role in human diseases, and we also review emerging data from our laboratory revealing the potential role of lipid droplets from Hensen cells in the auditory organ. We suggest that lipid droplets might help to develop rapidly and efficiently the resolution phase of inflammatory responses in the mammalian cochlea, preventing inflammatory damage of the delicate inner ear structures and, consequently, sensorineural hearing loss.
Collapse
Affiliation(s)
- Raul A Urrutia
- Epigenetics and Chromatin Dynamics Laboratory, Translational Epigenomic Program, Center for Individualized Medicine (CIM) Mayo Clinic, Rochester, MN 55905, USA
| | - Federico Kalinec
- Laboratory of Auditory Cell Biology, Department of Head & Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| |
Collapse
|
22
|
Medeiros AI, Secatto A, Bélanger C, Sorgi CA, Borgeat P, Marleau S, Faccioli LH. Impairment of neutrophil migration to remote inflammatory site during lung histoplasmosis. Biomed Res Int 2015; 2015:409309. [PMID: 25710004 DOI: 10.1155/2015/409309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 01/07/2015] [Accepted: 01/09/2015] [Indexed: 11/17/2022]
Abstract
Histoplasma capsulatum (Hc) induces a pulmonary disease in which leukotrienes promote activation and recruitment of effectors cells. It is also well-recognized that leukotriene B4 (LTB4) and platelet-activating factor (PAF) induce leukocyte recruitment to inflammatory sites. We investigated the impact of pulmonary Hc infection on PMN migration to a remote inflammatory site. Our results show that pulmonary Hc infection impairs LTB4- or PAF-stimulated PMN recruitment to air pouch. Yet, remote inflammation did not modify PMN numbers in the bronchoalveolar lavage fluid (BALF) of Hc-infected mice. Interestingly, the concomitant administration of PAF and LTB4 receptor antagonists inhibited PMN recruitment to both BALF and the remote site, demonstrating cooperation between both mediators. Along that line, our results show that PAF-elicited PMN chemotaxis was abrogated in 5-lipoxygenase-deficient animals. These results suggest caution in the indiscriminate use of anti-inflammatory drugs during infectious diseases.
Collapse
|
23
|
Greineisen WE, Speck M, Shimoda LMN, Sung C, Phan N, Maaetoft-Udsen K, Stokes AJ, Turner H. Lipid body accumulation alters calcium signaling dynamics in immune cells. Cell Calcium 2014; 56:169-80. [PMID: 25016314 DOI: 10.1016/j.ceca.2014.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 06/17/2014] [Accepted: 06/18/2014] [Indexed: 10/25/2022]
Abstract
There is well-established variability in the numbers of lipid bodies (LB) in macrophages, eosinophils, and neutrophils. Similarly to the steatosis observed in adipocytes and hepatocytes during hyperinsulinemia and nutrient overload, immune cell LB hyper-accumulate in response to bacterial and parasitic infection and inflammatory presentations. Recently we described that hyperinsulinemia, both in vitro and in vivo, drives steatosis and phenotypic changes in primary and transformed mast cells and basophils. LB reach high numbers in these steatotic cytosols, and here we propose that they could dramatically impact the transcytoplasmic signaling pathways. We compared calcium release and influx responses at the population and single cell level in normal and steatotic model mast cells. At the population level, all aspects of FcɛRI-dependent calcium mobilization, as well as activation of calcium-dependent downstream signaling targets such as NFATC1 phosphorylation are suppressed. At the single cell level, we demonstrate that LB are both sources and sinks of calcium following FcɛRI cross-linking. Unbiased analysis of the impact of the presence of LB on the rate of trans-cytoplasmic calcium signals suggest that LB enrichment accelerates calcium propagation, which may reflect a Bernoulli effect. LB abundance thus impacts this fundamental signaling pathway and its downstream targets.
Collapse
Affiliation(s)
- William E Greineisen
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Mark Speck
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Lori M N Shimoda
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Carl Sung
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Nolwenn Phan
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Kristina Maaetoft-Udsen
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States
| | - Alexander J Stokes
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, United States
| | - Helen Turner
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI, United States; Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, United States.
| |
Collapse
|
24
|
Furtado JL, Oliveira GA, Pontes AS, Setúbal Sda S, Xavier CV, Lacouth-Silva F, Lima BF, Zaqueo KD, Kayano AM, Calderon LA, Stábeli RG, Soares AM, Zuliani JP. Activation of J77A.1 macrophages by three phospholipases A2 isolated from Bothrops atrox snake venom. Biomed Res Int 2014; 2014:683123. [PMID: 24592395 DOI: 10.1155/2014/683123] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/18/2013] [Accepted: 11/18/2013] [Indexed: 12/22/2022]
Abstract
In the present study, we investigated the in vitro effects of two basic myotoxic phospholipases A2 (PLA2), BaTX-I, a catalytically inactive Lys-49 variant, and BaTX-II, a catalytically active Asp-49, and of one acidic myotoxic PLA2, BaPLA2, a catalytically active Asp-49, isolated from Bothrops atrox snake venom, on the activation of J774A.1 macrophages. At noncytotoxic concentrations, the toxins did not affect the adhesion of the macrophages, nor their ability to detach. The data obtained showed that only BaTX-I stimulated complement receptor-mediated phagocytosis. However, BaTX-I, BaTX-II, and BaPLA2 induced the release of the superoxide anion by J774A.1 macrophages. Additionally, only BaTX-I raised the lysosomal volume of macrophages after 15 min of incubation. After 30 min, all the phospholipases increased this parameter, which was not observed within 60 min. Moreover, BaTX-I, BaTX-II, and BaPLA2 increased the number of lipid bodies on macrophages submitted to phagocytosis and not submitted to phagocytosis. However, BaTX-II and BaPLA2 induced the release of TNF-α by J774A.1 macrophages. Taken together, the data show that, despite differences in enzymatic activity, the three toxins induced inflammatory events and whether the enzyme is acidic or basic does not seem to contribute to these effects.
Collapse
|
25
|
Gonçalves-de-Albuquerque CF, Burth P, Silva AR, de Moraes IMM, de Jesus Oliveira FM, Santelli RE, Freire AS, Bozza PT, Younes-Ibrahim M, de Castro-Faria-Neto HC, de Castro-Faria MV. Oleic acid inhibits lung Na/K-ATPase in mice and induces injury with lipid body formation in leukocytes and eicosanoid production. J Inflamm (Lond) 2013; 10:34. [PMID: 24175969 PMCID: PMC4177532 DOI: 10.1186/1476-9255-10-34] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 10/28/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Acute respiratory distress syndrome (ARDS) can emerge from certain pathologies, such as sepsis, fat embolism and leptospirosis, in which the levels of unesterified fatty acids are increased in the patient's plasma. ARDS is characterized by edema formation, and edema resolution occurs mainly due to the pneumocyte Na/K-ATPase activity. As previously described, increased oleic acid (OA) plasma concentrations induce lung injury by interfering with sodium transport. The first aim of this study was to develop a radioactivity-free assay to detect Na,K-ATPase activity ex vivo using a model of OA-induced lung injury in mice. We also investigated the relationship between Na/K-ATPase inhibition and OA-induced lung injury using ouabain-induced lung injury as a comparison, because of the well-described effect of ouabain as a Na/K-ATPase inhibitor. METHODS We developed a Na/K-ATPase assay based on the capture of non-radioactive Rb+ ions by mice lung tissue in the absence or presence of ouabain, a specific Na/K-ATPase inhibitor. Rb+ incorporation into the lung was measured by inductively coupled plasma-optical emission spectrometry (ICP-OES) after lung tissue mineralization. Na/K-ATPase activity was considered as the difference between Rb+ incorporation in the absence and in the presence of ouabain. Bronchoalveolar lavage fluid was collected for lung injury assessment. For this assessment, cell counting, lipid body enumeration and lipid mediator concentrations were measured. Histological analyses were used to determinate lung pathology. Whole body plethysmographic analysis was performed to assay lung function. RESULTS The lung Na/K-ATPase activity of mice was completely inhibited by an OA dose of 10 μmol, an effect also obtained with 10-3 μmol of ouabain, as demonstrated by the decreased Rb+ incorporation in the lungs. The same OA dose induced lung edema and inflammation with cell influx, lipid body formation, and leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) production. Ouabain also induced lung inflammation, as detected by histological examinations. As far as we know, this is the first time that ouabain-induced lung injury was shown. Both OA and ouabain induced functional lung pathology in mice simultaneously with inhibition of the lung Na/K-ATPase activity. CONCLUSIONS We developed a new non-radioactive assay to quantified Na/K-ATPase in vivo. OA and ouabain inhibited in vivo Na/K-ATPase activity in the lungs and induced lung injury. Our data reinforce the idea that Na/K-ATPase inhibitors may worsen lung injury in specific pathological conditions.
Collapse
Affiliation(s)
| | - Patrícia Burth
- Departamento de Biologia Celular e Molecular, Instituto de Biologia, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Adriana Ribeiro Silva
- Instituto Oswaldo Cruz, Laboratório de Imunofarmacologia, Fiocruz, Rio de Janeiro, RJ, Brazil
| | | | | | - Ricardo Erthal Santelli
- Departamento de Química Analítica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Aline Soares Freire
- Departamento de Química Analítica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Patrícia Torres Bozza
- Instituto Oswaldo Cruz, Laboratório de Imunofarmacologia, Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Mauricio Younes-Ibrahim
- Departamento de Medicina Interna, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Mauro Velho de Castro-Faria
- Departamento de Medicina Interna, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| |
Collapse
|
26
|
Melo RCN, Paganoti GF, Dvorak AM, Weller PF. The internal architecture of leukocyte lipid body organelles captured by three-dimensional electron microscopy tomography. PLoS One 2013; 8:e59578. [PMID: 23555714 PMCID: PMC3608657 DOI: 10.1371/journal.pone.0059578] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/15/2013] [Indexed: 01/04/2023] Open
Abstract
Lipid bodies (LBs), also known as lipid droplets, are complex organelles of all eukaryotic cells linked to a variety of biological functions as well as to the development of human diseases. In cells from the immune system, such as eosinophils, neutrophils and macrophages, LBs are rapidly formed in the cytoplasm in response to inflammatory and infectious diseases and are sites of synthesis of eicosanoid lipid mediators. However, little is known about the structural organization of these organelles. It is unclear whether leukocyte LBs contain a hydrophobic core of neutral lipids as found in lipid droplets from adipocytes and how diverse proteins, including enzymes involved in eicosanoid formation, incorporate into LBs. Here, leukocyte LB ultrastructure was studied in detail by conventional transmission electron microscopy (TEM), immunogold EM and electron tomography. By careful analysis of the two-dimensional ultrastructure of LBs from human blood eosinophils under different conditions, we identified membranous structures within LBs in both resting and activated cells. Cyclooxygenase, a membrane inserted protein that catalyzes the first step in prostaglandin synthesis, was localized throughout the internum of LBs. We used fully automated dual-axis electron tomography to study the three-dimensional architecture of LBs in high resolution. By tracking 4 nm-thick serial digital sections we found that leukocyte LBs enclose an intricate system of membranes within their “cores”. After computational reconstruction, we showed that these membranes are organized as a network of tubules which resemble the endoplasmic reticulum (ER). Our findings explain how membrane-bound proteins interact and are spatially arranged within LB “cores” and support a model for LB formation by incorporating cytoplasmic membranes of the ER, instead of the conventional view that LBs emerge from the ER leaflets. This is important to understand the functional capabilities of leukocyte LBs in health and during diverse diseases in which these organelles are functionally involved.
Collapse
Affiliation(s)
- Rossana C. N. Melo
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora, UFJF, Juiz de Fora, MG, Brazil
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Guillherme F. Paganoti
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora, UFJF, Juiz de Fora, MG, Brazil
| | - Ann M. Dvorak
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Peter F. Weller
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
27
|
Gonçalves-de-Albuquerque CF, Silva AR, Burth P, de Moraes IMM, Oliveira FMDJ, Younes-Ibrahim M, dos Santos MDCB, D'Ávila H, Bozza PT, Faria Neto HCDC, Faria MVDC. Oleic acid induces lung injury in mice through activation of the ERK pathway. Mediators Inflamm 2012; 2012:956509. [PMID: 23209347 PMCID: PMC3504460 DOI: 10.1155/2012/956509] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 10/18/2012] [Indexed: 01/06/2023] Open
Abstract
Oleic acid (OA) can induce acute lung injury in experimental models. In the present work, we used intratracheal OA injection to show augmented oedema formation, cell migration and activation, lipid mediator, and cytokine productions in the bronchoalveolar fluids of Swiss Webster mice. We also demonstrated that OA-induced pulmonary injury is dependent on ERK1/2 activation, since U0126, an inhibitor of ERK1/2 phosphorylation, blocked neutrophil migration, oedema, and lipid body formation as well as IL-6, but not IL-1β production. Using a mice strain carrying a null mutation for the TLR4 receptor, we proved that increased inflammatory parameters after OA challenges were not due to the activation of the TLR4 receptor. With OA being a Na/K-ATPase inhibitor, we suggest the possible involvement of this enzyme as an OA target triggering lung inflammation.
Collapse
|
28
|
Othy S, Bruneval P, Topçu S, Dugail I, Delers F, Lacroix-Desmazes S, Bayry J, Kaveri SV. Effect of IVIg on human dendritic cell-mediated antigen uptake and presentation: Role of lipid accumulation. J Autoimmun 2012; 39:168-72. [DOI: 10.1016/j.jaut.2012.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 05/20/2012] [Indexed: 11/25/2022]
|
29
|
Robciuc A, Hyötyläinen T, Jauhiainen M, Holopainen JM. Hyperosmolarity-induced lipid droplet formation depends on ceramide production by neutral sphingomyelinase 2. J Lipid Res 2012; 53:2286-95. [PMID: 22899568 DOI: 10.1194/jlr.m026732] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Hyperosmolarity (HO) imposes a remarkable stress on membranes, especially in tissues in direct contact with the external environment. Our efforts were focused on revealing stress-induced lipid changes that precede the inflammatory cytokine response in human corneal epithelial cells exposed to increasing osmolarity. We used a lipidomic analysis that detected significant and systematic changes in the lipid profile, highly correlated with sodium concentrations in the medium. Ceramides and triglycerides (TGs) were the most-responsive lipid classes, with gradual increases of up to 2- and 3-fold, respectively, when compared with control. The source of ceramide proved to be sphingomyelin hydrolysis, and neutral sphingomyelinase 2 (NSM2) activity showed a 2-fold increase 1 h after HO stress, whereas transcription increased 3-fold. Both TG accumulation and IL-8 secretion were shown to be dependent on ceramide production by specific knock-down of NSM2. In HCE cells, diglyceride acyltransferase 1 was responsible for the TG synthesis, but the enzyme activity had no effect on cytokine secretion. Hence, NSM2 plays a key role in the cellular response to hyperosmolar stress, and its activity regulates both cytokine secretion and lipid droplet formation.
Collapse
Affiliation(s)
- Alexandra Robciuc
- Helsinki Eye Lab, Department of Ophthalmology, Haartmaninkatu 4 C, University of Helsinki, 00290 Helsinki, Finland
| | | | | | | |
Collapse
|
30
|
Gonçalves de Albuquerque CF, Burth P, Younes Ibrahim M, Garcia DG, Bozza PT, Castro Faria Neto HC, Castro Faria MV. Reduced plasma nonesterified fatty acid levels and the advent of an acute lung injury in mice after intravenous or enteral oleic acid administration. Mediators Inflamm 2012; 2012:601032. [PMID: 22529526 DOI: 10.1155/2012/601032] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 11/12/2011] [Accepted: 11/13/2011] [Indexed: 01/11/2023] Open
Abstract
Although exerting valuable functions in living organisms, nonesterified fatty acids (NEFAs) can be toxic to cells. Increased blood concentration of oleic acid (OLA) and other fatty acids is detected in many pathological conditions. In sepsis and leptospirosis, high plasma levels of NEFA and low albumin concentrations are correlated to the disease severity. Surprisingly, 24 h after intravenous or intragastric administration of OLA, main NEFA levels (OLA inclusive) were dose dependently decreased. However, lung injury was detected in intravenously treated mice, and highest dose killed all mice. When administered by the enteral route, OLA was not toxic in any tested conditions. Results indicate that OLA has important regulatory properties on fatty acid metabolism, possibly lowering circulating fatty acid through activation of peroxisome proliferator-activated receptors. The significant reduction in blood NEFA levels detected after OLA enteral administration can contribute to the already known health benefits brought about by unsaturated-fatty-acid-enriched diets.
Collapse
|
31
|
Barnés CM, Prox D, Christison-Lagay EA, Le HD, Short S, Cassiola F, Panigrahy D, Chaponis D, Butterfield C, Nehra D, Fallon EM, Kieran M, Folkman J, Puder M. Inhibition of neuroblastoma cell proliferation with omega-3 fatty acids and treatment of a murine model of human neuroblastoma using a diet enriched with omega-3 fatty acids in combination with sunitinib. Pediatr Res 2012; 71:168-78. [PMID: 22258128 DOI: 10.1038/pr.2011.28] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
INTRODUCTION We investigated the use of dietary omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) in the treatment of neuroblastoma both as a sole agent and in combination with sunitinib, a broad-spectrum tyrosine kinase receptor inhibitor. RESULTS Substitution of all dietary fat with menhaden oil (ω-3 PUFA rich) resulted in a 40-70% inhibition of tumor growth and a statistically significant difference in the levels of several PUFAs (18:2 ω-6, 20:4 ω-6, 22:4 ω-6, 20:5 ω-3) as compared with a control diet. Furthermore, tumors from animals on the ω-3 fatty acid (FA)-enriched diet had an elevated triene/tetraene ratio suggestive of a change in local eicosanoid metabolism in these tissues similar to that seen with essential fatty acid deficiency. The ω-3 FA-enriched diet also decreased tumor-associated inflammatory cells and induced mitochondrial changes suggestive of mitochondrial damage. Combination treatment with sunitinib resulted in further reduction in tumor proliferation and microvessel density. DISCUSSION These findings suggest a potential role for ω-3 PUFAs in the combination treatment of neuroblastoma. METHODS We used a murine model of orthotopic and subcutaneous human neuroblastoma and diets that differ in the FA content to define the optimal dietary ω-3/omega-6 (ω-6) FA ratio required for the inhibition of these tumors.
Collapse
|
32
|
Luna-Gomes T, Magalhães KG, Mesquita-Santos FP, Bakker-Abreu I, Samico RF, Molinaro R, Calheiros AS, Diaz BL, Bozza PT, Weller PF, Bandeira-Melo C. Eosinophils as a novel cell source of prostaglandin D2: autocrine role in allergic inflammation. J Immunol 2011; 187:6518-26. [PMID: 22102725 DOI: 10.4049/jimmunol.1101806] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
PGD(2) is a key mediator of allergic inflammatory diseases that is mainly synthesized by mast cells, which constitutively express high levels of the terminal enzyme involved in PGD(2) synthesis, the hematopoietic PGD synthase (H-PGDS). In this study, we investigated whether eosinophils are also able to synthesize, and therefore, supply biologically active PGD(2). PGD(2) synthesis was evaluated within human blood eosinophils, in vitro differentiated mouse eosinophils, and eosinophils infiltrating inflammatory site of mouse allergic reaction. Biological function of eosinophil-derived PGD(2) was studied by employing inhibitors of synthesis and activity. Constitutive expression of H-PGDS was found within nonstimulated human circulating eosinophils. Acute stimulation of human eosinophils with A23187 (0.1-5 μM) evoked PGD(2) synthesis, which was located at the nuclear envelope and was inhibited by pretreatment with HQL-79 (10 μM), a specific H-PGDS inhibitor. Prestimulation of human eosinophils with arachidonic acid (10 μM) or human eotaxin (6 nM) also enhanced HQL-79-sensitive PGD(2) synthesis, which, by acting on membrane-expressed specific receptors (D prostanoid receptors 1 and 2), displayed an autocrine/paracrine ability to trigger leukotriene C(4) synthesis and lipid body biogenesis, hallmark events of eosinophil activation. In vitro differentiated mouse eosinophils also synthesized paracrine/autocrine active PGD(2) in response to arachidonic acid stimulation. In vivo, at late time point of the allergic reaction, infiltrating eosinophils found at the inflammatory site appeared as an auxiliary PGD(2)-synthesizing cell population. Our findings reveal that eosinophils are indeed able to synthesize and secrete PGD(2), hence representing during allergic inflammation an extra cell source of PGD(2), which functions as an autocrine signal for eosinophil activation.
Collapse
Affiliation(s)
- Tatiana Luna-Gomes
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Abstract
Eicosanoids (prostaglandins, leukotrienes and lipoxins) are signaling lipids derived from arachidonic acid metabolism that have important roles in physiological and pathological processes. Lately, intracellular compartmentalization of eicosanoid-synthetic machinery has emerged as a key component in the regulation of eicosanoid synthesis and functions. Over the past years substantial progresses have been made demonstrating that precursors and enzymes involved in eicosanoid synthesis localize at lipid bodies (also known as lipid droplets) and lipid bodies are distinct sites for eicosanoid generation. Here we will review the current knowledge on the functions of lipid bodies as specialized intracellular sites of compartmentalization of signaling with major roles in eicosanoid formation within cells engaged in inflammatory, infectious and neoplastic process.
Collapse
Affiliation(s)
- Patricia T Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, FIOCRUZ, Brazil.
| | | | | | | |
Collapse
|
34
|
D'Avila H, Freire-de-Lima CG, Roque NR, Teixeira L, Barja-Fidalgo C, Silva AR, Melo RCN, Dosreis GA, Castro-Faria-Neto HC, Bozza PT. Host cell lipid bodies triggered by Trypanosoma cruzi infection and enhanced by the uptake of apoptotic cells are associated with prostaglandin E₂ generation and increased parasite growth. J Infect Dis 2011; 204:951-61. [PMID: 21849292 DOI: 10.1093/infdis/jir432] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Lipid bodies (lipid droplets) are lipid-rich organelles with functions in cell metabolism and signaling. Here, we investigate the mechanisms of Trypanosoma cruzi-induced lipid body formation and their contributions to host-parasite interplay. We demonstrate that T. cruzi-induced lipid body formation in macrophages occurs in a Toll-like receptor 2-dependent mechanism and is potentiated by apoptotic cell uptake. Lipid body biogenesis and prostaglandin E₂ (PGE₂) production triggered by apoptotic cell uptake was largely dependent of α(v)β₃ and transforming growth factor-β signaling. T. cruzi-induced lipid bodies act as sites of increased PGE synthesis. Inhibition of lipid body biogenesis by the fatty acid synthase inhibitor C75 reversed the effects of apoptotic cells on lipid body formation, eicosanoid synthesis, and parasite replication. Our findings indicate that lipid bodies are highly regulated organelles during T. cruzi infection with roles in lipid mediator generation by macrophages and are potentially involved in T. cruzi-triggered escape mechanisms.
Collapse
Affiliation(s)
- Heloisa D'Avila
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Mattos KA, Oliveira VGC, D'Avila H, Rodrigues LS, Pinheiro RO, Sarno EN, Pessolani MCV, Bozza PT. TLR6-driven lipid droplets in Mycobacterium leprae-infected Schwann cells: immunoinflammatory platforms associated with bacterial persistence. J Immunol 2011; 187:2548-58. [PMID: 21813774 DOI: 10.4049/jimmunol.1101344] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mechanisms responsible for nerve injury in leprosy need further elucidation. We recently demonstrated that the foamy phenotype of Mycobacterium leprae-infected Schwann cells (SCs) observed in nerves of multibacillary patients results from the capacity of M. leprae to induce and recruit lipid droplets (LDs; also known as lipid bodies) to bacterial-containing phagosomes. In this study, we analyzed the parameters that govern LD biogenesis by M. leprae in SCs and how this contributes to the innate immune response elicited by M. leprae. Our observations indicated that LD formation requires the uptake of live bacteria and depends on host cell cytoskeleton rearrangement and vesicular trafficking. TLR6 deletion, but not TLR2, completely abolished the induction of LDs by M. leprae, as well as inhibited the bacterial uptake in SCs. M. leprae-induced LD biogenesis correlated with increased PGE(2) and IL-10 secretion, as well as reduced IL-12 and NO production in M. leprae-infected SCs. Analysis of nerves from lepromatous leprosy patients showed colocalization of M. leprae, LDs, and cyclooxygenase-2 in SCs, indicating that LDs are sites for PGE(2) synthesis in vivo. LD biogenesis Inhibition by the fatty acid synthase inhibitor C-75 abolished the effect of M. leprae on SC production of immunoinflammatory mediators and enhanced the mycobacterial-killing ability of SCs. Altogether, our data indicated a critical role for TLR6-dependent signaling in M. leprae-SC interactions, favoring phagocytosis and subsequent signaling for induction of LD biogenesis in infected cells. Moreover, our observations reinforced the role of LDs favoring mycobacterial survival and persistence in the nerve. These findings give further support to a critical role for LDs in M. leprae pathogenesis in the nerve.
Collapse
Affiliation(s)
- Katherine A Mattos
- Laboratory of Cellular Microbiology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ 21045-900, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Melo RCN, D'Avila H, Wan HC, Bozza PT, Dvorak AM, Weller PF. Lipid bodies in inflammatory cells: structure, function, and current imaging techniques. J Histochem Cytochem 2011; 59:540-56. [PMID: 21430261 DOI: 10.1369/0022155411404073] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipid bodies (LBs), also known as lipid droplets, have increasingly been recognized as functionally active organelles linked to diverse biological functions and human diseases. These organelles are actively formed in vivo within cells from the immune system, such as macrophages, neutrophils, and eosinophils, in response to different inflammatory conditions and are sites for synthesis and storage of inflammatory mediators. In this review, the authors discuss structural and functional aspects of LBs and current imaging techniques to visualize these organelles in cells engaged in inflammatory processes, including infectious diseases. The dynamic morphological aspects of LBs in leukocytes as inducible, newly formable organelles, elicitable in response to stimuli that lead to cellular activation, contribute to the evolving understanding of LBs as organelles that are critical regulators of different inflammatory diseases, key markers of leukocyte activation, and attractive targets for novel anti-inflammatory therapies.
Collapse
Affiliation(s)
- Rossana C N Melo
- Laboratory of Cellular Biology, Department of Biology, Federal University of Juiz de Fora (UFJF), Juiz de Fora, MG, Brazil.
| | | | | | | | | | | |
Collapse
|
37
|
Bozaquel-Morais BL, Madeira JB, Maya-Monteiro CM, Masuda CA, Montero-Lomeli M. A new fluorescence-based method identifies protein phosphatases regulating lipid droplet metabolism. PLoS One 2010; 5:e13692. [PMID: 21060891 PMCID: PMC2965658 DOI: 10.1371/journal.pone.0013692] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 10/06/2010] [Indexed: 11/19/2022] Open
Abstract
In virtually every cell, neutral lipids are stored in cytoplasmic structures called lipid droplets (LDs) and also referred to as lipid bodies or lipid particles. We developed a rapid high-throughput assay based on the recovery of quenched BODIPY-fluorescence that allows to quantify lipid droplets. The method was validated by monitoring lipid droplet turnover during growth of a yeast culture and by screening a group of strains deleted in genes known to be involved in lipid metabolism. In both tests, the fluorimetric assay showed high sensitivity and good agreement with previously reported data using microscopy. We used this method for high-throughput identification of protein phosphatases involved in lipid droplet metabolism. From 65 yeast knockout strains encoding protein phosphatases and its regulatory subunits, 13 strains revealed to have abnormal levels of lipid droplets, 10 of them having high lipid droplet content. Strains deleted for type I protein phosphatases and related regulators (ppz2, gac1, bni4), type 2A phosphatase and its related regulator (pph21 and sap185), type 2C protein phosphatases (ptc1, ptc4, ptc7) and dual phosphatases (pps1, msg5) were catalogued as high-lipid droplet content strains. Only reg1, a targeting subunit of the type 1 phosphatase Glc7p, and members of the nutrient-sensitive TOR pathway (sit4 and the regulatory subunit sap190) were catalogued as low-lipid droplet content strains, which were studied further. We show that Snf1, the homologue of the mammalian AMP-activated kinase, is constitutively phosphorylated (hyperactive) in sit4 and sap190 strains leading to a reduction of acetyl-CoA carboxylase activity. In conclusion, our fast and highly sensitive method permitted us to catalogue protein phosphatases involved in the regulation of LD metabolism and present evidence indicating that the TOR pathway and the SNF1/AMPK pathway are connected through the Sit4p-Sap190p pair in the control of lipid droplet biogenesis.
Collapse
Affiliation(s)
- Bruno L. Bozaquel-Morais
- Instituto de Bioquímica Médica, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Juliana B. Madeira
- Instituto de Bioquímica Médica, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa M. Maya-Monteiro
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Claudio A. Masuda
- Instituto de Bioquímica Médica, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Mónica Montero-Lomeli
- Instituto de Bioquímica Médica, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
| |
Collapse
|
38
|
Paiva LA, Maya-Monteiro CM, Bandeira-Melo C, Silva PMR, El-Cheikh MC, Teodoro AJ, Borojevic R, Perez SAC, Bozza PT. Interplay of cysteinyl leukotrienes and TGF-β in the activation of hepatic stellate cells from Schistosoma mansoni granulomas. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1801:1341-8. [PMID: 20817008 DOI: 10.1016/j.bbalip.2010.08.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 08/19/2010] [Accepted: 08/27/2010] [Indexed: 12/22/2022]
Abstract
Hepatic stellate cells (HSCs) have a critical role in liver physiology, and in the pathogenesis of liver inflammation and fibrosis. Here, we investigated the interplay between leukotrienes (LT) and TGF-β in the activation mechanisms of HSCs from schistosomal granulomas (GR-HSCs). First, we demonstrated that GR-HSCs express 5-lipoxygenase (5-LO), as detected by immunolocalization in whole cells and confirmed in cell lysates through western blotting and by mRNA expression through RT-PCR. Moreover, mRNA expression of 5-LO activating protein (FLAP) and LTC(4)-synthase was also documented, indicating that GR-HSCs have the molecular machinery required for LT synthesis. Morphological analysis of osmium and Oil-Red O-stained HSC revealed large numbers of small lipid droplets (also known as lipid bodies). We observed co-localization of lipid droplet protein marker (ADRP) and 5-LO by immunofluorescence microscopy. We demonstrated that GR-HSCs were able to spontaneously release cysteinyl-LTs (CysLTs), but not LTB(4,) into culture supernatants. CysLT production was highly enhanced after TGF-β-stimulation. Moreover, the 5-LO inhibitor zileuton and 5-LO gene deletion were able to inhibit the TGF-β-stimulated proliferation of GR-HSCs, suggesting a role for LTs in HSC activation. Here, we extend the immunoregulatory function of HSC by demonstrating that HSC from liver granulomas of schistosome-infected mouse are able to release Cys-LTs in a TGF-β-regulated manner, potentially impacting pathogenesis and liver fibrosis in schistosomiasis.
Collapse
Affiliation(s)
- Ligia A Paiva
- Laboratory of Immunopharmacology, Institute Oswaldo Cruz, Manguinhos, Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Strillacci A, Griffoni C, Valerii MC, Lazzarini G, Tomasi V, Spisni E. RNAi-based strategies for cyclooxygenase-2 inhibition in cancer. J Biomed Biotechnol 2010; 2010:828045. [PMID: 20625420 DOI: 10.1155/2010/828045] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 03/18/2010] [Accepted: 04/08/2010] [Indexed: 12/19/2022] Open
Abstract
Cyclooxygenase-2 (COX-2) enzyme has been involved in the tumorigenesis and in the progression of colorectal cancer (CRC). The use of traditional nonsteroidal anti-inflammatory drugs (NSAIDs) or selective COX-2 inhibitors has been proposed for the prevention and the treatment of this relevant neoplastic disease. In the light of an innovative alternative to these pharmacological approaches, we review here the possible strategies to achieve a strong and selective inhibition of COX-2 enzyme by using the mechanism of RNA Interference (RNAi) targeted against its mRNA. Anti-COX-2 siRNA molecules (siCOX-2) can be generated in CRC cells from short hairpin RNA (shRNA) precursors, delivered in vitro by a retroviral expression system, and induce a significant and stable silencing of overexpressed COX-2 in human colon cancer cells. As a safer alternative to viral approach, nonpathogenic bacteria (E. coli) can be engineered to invade eukaryotic cells and to generate siCOX-2 molecules in cancer cells. Moreover, the involvement of miRNAs in COX-2 posttranscriptional regulation opens up the possibility to exploit an endogenous silencing mechanism to knockdown overexpressed COX-2. Thus, these recent strategies disclose new challenging perspectives for the development of clinically compatible siRNA or miRNA capable of selectively inhibiting COX-2 enzyme.
Collapse
|
40
|
Abstract
Accumulation of lipid droplets (also known as lipid bodies or adiposomes) within leukocytes, epithelial cells, hepatocytes and other non-adipocytic cells is a frequently observed phenotype in infectious, neoplastic and other inflammatory conditions. Lipid droplet biogenesis is a regulated cellular process that culminates in the compartmentalization of lipids and of an array of enzymes, protein kinases and other proteins, suggesting that lipid droplets are inducible organelles with roles in cell signaling, regulation of lipid metabolism, membrane trafficking and control of the synthesis and secretion of inflammatory mediators. Enzymes involved in eicosanoid synthesis are localized at lipid droplets and lipid droplets are sites for eicosanoid generation in cells during inflammation and cancer. In this review, we discuss the current evidence related to the biogenesis and function of lipid droplets in cell metabolism and signaling in inflammation and cancer. Moreover, the potential of lipid droplets as markers of disease and targets for novel anti-inflammatory and antineoplastic therapies will be discussed.
Collapse
Affiliation(s)
- Patricia T Bozza
- Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
| | | |
Collapse
|
41
|
den Hartigh LJ, Connolly-Rohrbach JE, Fore S, Huser TR, Rutledge JC. Fatty acids from very low-density lipoprotein lipolysis products induce lipid droplet accumulation in human monocytes. J Immunol 2010; 184:3927-36. [PMID: 20208007 DOI: 10.4049/jimmunol.0903475] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
One mechanism by which monocytes become activated postprandially is by exposure to triglyceride-rich lipoproteins such as very low-density lipoproteins (VLDL). VLDL are hydrolyzed by lipoprotein lipase at the blood-endothelial cell interface, releasing free fatty acids. In this study, we examined postprandial monocyte activation in more detail, and found that lipolysis products generated from postprandial VLDL induce the formation of lipid-filled droplets within cultured THP-1 monocytes, characterized by coherent antistokes Raman spectroscopy. Organelle-specific stains revealed an association of lipid droplets with the endoplasmic reticulum, confirmed by electron microscopy. Lipid droplet formation was reduced when lipoprotein lipase-released fatty acids were bound by BSA, which also reduced cellular inflammation. Furthermore, saturated fatty acids induced more lipid droplet formation in monocytes compared with mono- and polyunsaturated fatty acids. Monocytes treated with postprandial VLDL lipolysis products contained lipid droplets with more intense saturated Raman spectroscopic signals than monocytes treated with fasting VLDL lipolysis products. In addition, we found that human monocytes isolated during the peak postprandial period contain more lipid droplets compared with those from the fasting state, signifying that their development is not limited to cultured cells but also occurs in vivo. In summary, circulating free fatty acids can mediate lipid droplet formation in monocytes and potentially be used as a biomarker to assess an individual's risk of developing atherosclerotic cardiovascular disease.
Collapse
Affiliation(s)
- Laura J den Hartigh
- Division of Endocrinology, Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
| | | | | | | | | |
Collapse
|
42
|
Bozza PT, D’Avila H, Almeida PE, Magalhães KG, Molinaro R, Almeida CJ, Maya-Monteiro CM. Lipid droplets in host–pathogen interactions. ACTA ACUST UNITED AC 2009. [DOI: 10.2217/clp.09.63] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
43
|
Nanhuck RM, Doublet A, Yaqoob P. Effects of lipid emulsions on lipid body formation and eicosanoid production by human peripheral blood mononuclear and polymorphonuclear cells. Clin Nutr 2009; 28:556-64. [DOI: 10.1016/j.clnu.2009.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 04/14/2009] [Accepted: 05/05/2009] [Indexed: 11/17/2022]
|
44
|
Bozza PT, Magalhães KG, Weller PF. Leukocyte lipid bodies - Biogenesis and functions in inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:540-51. [PMID: 19416659 DOI: 10.1016/j.bbalip.2009.01.005] [Citation(s) in RCA: 171] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Revised: 01/06/2009] [Accepted: 01/09/2009] [Indexed: 12/19/2022]
Abstract
Lipid body accumulation within leukocytes is a common feature in both clinical and experimental infectious, neoplasic and other inflammatory conditions. Here, we will review the contemporary evidence related to the biogenesis and structure of leukocyte lipid bodies (also known as lipid droplets) as inflammatory organelles. Studies of leukocyte lipid bodies are providing functional, ultrastructural and protein compositional evidences that lipid bodies are not solely storage depots of neutral lipid. Over the past years substantial progresses have been made to demonstrate that lipid body biogenesis is a highly regulated process, that culminate in the compartmentalization of a specific set of proteins and lipids, that place leukocyte lipid bodies as inducible cytoplasmic organelles with roles in cell signaling and activation, regulation of lipid metabolism, membrane trafficking and control of the synthesis and secretion of inflammatory mediators. Pertinent to the roles of lipid bodies in inflammation and cell signaling, enzymes involved in eicosanoid synthesis are localized at lipid bodies and lipid bodies are sites for eicosanoid generation. Collectively, lipid bodies in leukocytes are emerging as critical regulators of different inflammatory diseases, key markers of leukocyte activation and attractive targets for novel anti-inflammatory therapies.
Collapse
Affiliation(s)
- Patricia T Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Manguinhos, 21045-900, Rio de Janeiro, RJ, Brazil.
| | | | | |
Collapse
|
45
|
Pinheiro RO, Nunes MP, Pinheiro CS, D'Avila H, Bozza PT, Takiya CM, Côrte-Real S, Freire-de-Lima CG, DosReis GA. Induction of autophagy correlates with increased parasite load of Leishmania amazonensis in BALB/c but not C57BL/6 macrophages. Microbes Infect 2008; 11:181-90. [PMID: 19070676 DOI: 10.1016/j.micinf.2008.11.006] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 11/03/2008] [Accepted: 11/11/2008] [Indexed: 12/12/2022]
Abstract
We investigated the role of autophagy in infection of macrophages by Leishmania amazonensis. Induction of autophagy by IFN-gamma or starvation increased intracellular parasite load and the percentages of infected macrophages from BALB/c but not from C57BL/6 mice. In contrast, starvation did not affect the replication of either Leishmania major or Trypanosoma cruzi in BALB/c macrophages. In BALB/c macrophages, starvation resulted in increased monodansylcadaverine staining and in the appearance of double-membrane and myelin-like vesicles characteristic of autophagosomes. Increased parasite load was associated with a reduction in NO levels and was attenuated by wortmannin, an inhibitor of autophagy. In infected macrophages from BALB/c, but not from C57BL/6 mice, starvation increased the number of lipid bodies and the amounts of PGE(2) produced. Exogenous PGE(2) increased parasite load in macrophages from BALB/c, but not C57BL/6 mice. The cyclooxygenase inhibitor indomethacin prevented the increase of parasite load in starved BALB/c macrophages, and actually induced parasite killing. These results suggest that autophagy regulates the outcome of L. amazonensis infection in macrophages in a host strain specific manner.
Collapse
|
46
|
D'avila H, Maya-monteiro CM, Bozza PT. Lipid bodies in innate immune response to bacterial and parasite infections. Int Immunopharmacol 2008; 8:1308-15. [DOI: 10.1016/j.intimp.2008.01.035] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Accepted: 01/02/2008] [Indexed: 01/06/2023]
|
47
|
D'Avila H, Roque NR, Cardoso RM, Castro-Faria-Neto HC, Melo RCN, Bozza PT. Neutrophils recruited to the site of Mycobacterium bovis BCG infection undergo apoptosis and modulate lipid body biogenesis and prostaglandin E production by macrophages. Cell Microbiol 2008; 10:2589-604. [PMID: 18771558 DOI: 10.1111/j.1462-5822.2008.01233.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Neutrophil influx to sites of mycobacterial infections is one of the first events of tuberculosis pathogenesis. However, the role of early neutrophil recruitment in mycobacterial infection is not completely understood. We investigated the rate of neutrophil apoptosis and the role of macrophage uptake of apoptotic neutrophils in a pleural tuberculosis model induced by BCG. Recruited neutrophils were shown to phagocyte BCG and a large number of neutrophils undergo apoptosis within 24 h. Notably, the great majority of apoptotic neutrophils were infected by BCG. Increased lipid body (lipid droplets) formation, accompanied by prostaglandin E(2) (PGE(2)) and TGF-beta1 synthesis, occurred in parallel to macrophage uptake of apoptotic cells. Lipid body and PGE(2) formation was observed after macrophage exposure to apoptotic, but not necrotic or live neutrophils. Blockage of BCG-induced lipid body formation significantly inhibited PGE(2) synthesis. Pre-treatment with the pan-caspase inhibitor zVAD inhibited BCG-induced neutrophil apoptosis and lipid body formation, indicating a role for apoptotic neutrophils in macrophage lipid body biogenesis in infected mice. In conclusion, BCG infection induced activation and apoptosis of infected neutrophils at the inflammatory site. The uptake of apoptotic neutrophils by macrophages leads to TGF-beta1 generation and PGE(2)-derived lipid body formation, and may have modulator roles in mycobacterial pathogenesis.
Collapse
Affiliation(s)
- Heloisa D'Avila
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | |
Collapse
|
48
|
Gubern A, Casas J, Barceló-Torns M, Barneda D, de la Rosa X, Masgrau R, Picatoste F, Balsinde J, Balboa MA, Claro E. Group IVA phospholipase A2 is necessary for the biogenesis of lipid droplets. J Biol Chem 2008; 283:27369-27382. [PMID: 18632668 DOI: 10.1074/jbc.m800696200] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Lipid droplets (LD) are organelles present in all cell types, consisting of a hydrophobic core of triacylglycerols and cholesteryl esters, surrounded by a monolayer of phospholipids and cholesterol. This work shows that LD biogenesis induced by serum, by long-chain fatty acids, or the combination of both in CHO-K1 cells was prevented by phospholipase A(2) inhibitors with a pharmacological profile consistent with the implication of group IVA cytosolic phospholipase A(2) (cPLA(2)alpha). Knocking down cPLA(2)alpha expression with short interfering RNA was similar to pharmacological inhibition in terms of enzyme activity and LD biogenesis. A Chinese hamster ovary cell clone stably expressing an enhanced green fluorescent protein-cPLA(2)alpha fusion protein (EGFP-cPLA(2)) displayed higher LD occurrence under basal conditions and upon LD induction. Induction of LD took place with concurrent phosphorylation of cPLA(2)alpha at Ser(505). Transfection of a S505A mutant cPLA(2)alpha showed that phosphorylation at Ser(505) is key for enzyme activity and LD formation. cPLA(2)alpha contribution to LD biogenesis was not because of the generation of arachidonic acid, nor was it related to neutral lipid synthesis. cPLA(2)alpha inhibition in cells induced to form LD resulted in the appearance of tubulo-vesicular profiles of the smooth endoplasmic reticulum, compatible with a role of cPLA(2)alpha in the formation of nascent LD from the endoplasmic reticulum.
Collapse
Affiliation(s)
- Albert Gubern
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - Javier Casas
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas and Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, E-47003 Valladolid, Spain
| | - Miquel Barceló-Torns
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - David Barneda
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - Xavier de la Rosa
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - Roser Masgrau
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - Fernando Picatoste
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona
| | - Jesús Balsinde
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas and Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, E-47003 Valladolid, Spain
| | - María A Balboa
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas and Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, E-47003 Valladolid, Spain
| | - Enrique Claro
- Institut de Neurociències and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, E-08193 Barcelona.
| |
Collapse
|
49
|
Guruswamy S, Rao CV. Multi-Target Approaches in Colon Cancer Chemoprevention Based on Systems Biology of Tumor Cell-Signaling. Gene Regul Syst Bio 2008; 2:163-176. [PMID: 19763245 PMCID: PMC2745153 DOI: 10.4137/grsb.s486] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Colorectal cancer is the leading cause of cancer related deaths in the United States. Although it is preventable, thousands of lives are lost each year in the U.S. to colorectal cancer than to breast cancer and AIDS combined. In colon cancer, the formation and progression of precancerous lesions like aberrant crypt foci and polyps is associated with the up-regulation of cycloxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and hydroxy methyl glutaryl CoA reductase (HMG-CoA reductase). The current review will focus on the signaling pathway involving COX-2 and HMG-CoA reductase enzymes and their downstream effectors in signaling mechanism. Cancer cells need huge pools of both cholesterol and isoprenoids to sustain their unlimited growth potential. Cholesterol by modulating caveolae formation regulates several signaling molecules like AKT, IGFR, EGFR and Rho which are involved in cell growth and survival. Cholesterol is also essential for lipid body formation which serves as storage sites for COX-2, eicosanoids and caveolin-1. Experimental studies have identified important mechanisms showing that COX-2, caveolin-1, lipid bodies and prenylated proteins is involved in carcinogenesis. Therefore multi-target, multi-drug approach is the ideal choice for effective colon cancer chemoprevention. This review will give an overview of the two pathways, their signaling networks, and the interactions between the components of the two networks in the activation and regulation of cell signaling involving growth/survival and explain the rationale for colon cancer chemoprevention using COX-2 inhibitors and statins.
Collapse
Affiliation(s)
- Suresh Guruswamy
- Department of Medicine, Hematology-Oncology Section, University of Oklahoma Health Sciences Center, Oklahoma City, OK, U.S.A
| | | |
Collapse
|
50
|
Accioly MT, Pacheco P, Maya-Monteiro CM, Carrossini N, Robbs BK, Oliveira SS, Kaufmann C, Morgado-Diaz JA, Bozza PT, Viola JPB. Lipid bodies are reservoirs of cyclooxygenase-2 and sites of prostaglandin-E2 synthesis in colon cancer cells. Cancer Res 2008; 68:1732-40. [PMID: 18339853 DOI: 10.1158/0008-5472.can-07-1999] [Citation(s) in RCA: 254] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lipid bodies (lipid droplets) are emerging as dynamic organelles involved in lipid metabolism and inflammation. Increased lipid body numbers have been described in tumor cells; however, its functional significance in cancer has never been addressed. Here, we showed increased number of lipid bodies in tumor tissues from patients with adenocarcinoma of colon submitted to surgical resection when compared with an adjacent normal tissue. Accordingly, increased numbers of lipid bodies were observed in human colon adenocarcinoma cell lines and in a H-rasV12-transformed intestinal epithelial cell line (IEC-6 H-rasV12) compared with nontransformed IEC-6 cells. The functions of lipid bodies in eicosanoid synthesis in cancer cells were investigated. CACO-2 cells have increased expression of cyclooxygenase-2 (COX-2) when compared with IEC-6 cells. We showed by immunolocalization that, in addition to perinuclear stain, COX-2 and prostaglandin E (PGE) synthase present punctate cytoplasmic localizations that were concordant with adipose differentiation-related protein-labeled lipid bodies. The colocalization of COX-2 at lipid bodies was confirmed by immunoblot of subcellular fractionated cells. Direct localization of PGE(2) at its synthesis locale showed that lipid bodies are sources of eicosanoids in the transformed colon cancer cells. Treatment with either aspirin or the fatty acid synthase inhibitor C75 significantly reduced the number of lipid bodies and PGE(2) production in CACO-2 and in IEC-6 H-rasV12 cells with effects in cell proliferation. Together, our results showed that lipid bodies in colon cancer cells are dynamic and functional active organelles centrally involved in PGE(2) synthesis and may potentially have implications in the pathogenesis of adenocarcinoma of colon.
Collapse
Affiliation(s)
- Maria T Accioly
- Division of Cellular Biology, National Cancer Institute, Rio de Janeiro, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|