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Nishida T, Ayaori M, Arakawa J, Suenaga Y, Shiotani K, Uto-Kondo H, Komatsu T, Nakaya K, Endo Y, Sasaki M, Ikewaki K. Liver-specific Lxr inhibition represses reverse cholesterol transport in cholesterol-fed mice. Atherosclerosis 2024:117578. [PMID: 38797615 DOI: 10.1016/j.atherosclerosis.2024.117578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 04/26/2024] [Accepted: 05/07/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND AND AIMS High density lipoprotein (HDL) exerts an anti-atherosclerotic effect via reverse cholesterol transport (RCT). Several phases of RCT are transcriptionally controlled by Liver X receptors (Lxrs). Although macrophage Lxrs reportedly promote RCT, it is still uncertain whether hepatic Lxrs affect RCT in vivo. METHODS To inhibit Lxr-dependent pathways in mouse livers, we performed hepatic overexpression of sulfotransferase family cytosolic 2B member 1 (Sult2b1) using adenoviral vector (Ad-Sult2b1). Ad-Sult2b1 or the control virus was intravenously injected into wild type mice and Lxrα/β double knockout mice, under a normal or high-cholesterol diet. A macrophage RCT assay and an HDL kinetic study were performed. RESULTS Hepatic Sult2b1 overexpression resulted in reduced expression of Lxr-target genes - ATP-binding cassette transporter G5/G8, cholesterol 7α hydroxylase and Lxrα itself - respectively reducing or increasing cholesterol levels in HDL and apolipoprotein B-containing lipoproteins (apoB-L). A macrophage RCT assay revealed that Sult2b1 overexpression inhibited fecal excretion of macrophage-derived 3H-cholesterol only under a high-cholesterol diet. In an HDL kinetic study, Ad-Sult2b1 promoted catabolism/hepatic uptake of HDL-derived cholesterol, thereby reducing fecal excretion. Finally, in Lxrα/β double knockout mice, hepatic Sult2b1 overexpression increased apoB-L levels, but there were no differences in HDL levels or RCT compared to the control, indicating that Sult2b1-mediated effects on HDL/RCT and apoB-L were distinct: the former was Lxr-dependent, but not the latter. CONCLUSIONS Hepatic Lxr inhibition negatively regulates circulating HDL levels and RCT by reducing Lxr-target gene expression.
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Affiliation(s)
- Takafumi Nishida
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan.
| | - Makoto Ayaori
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan; Tokorozawa Heart Center, Tokorozawa, Japan
| | - Junko Arakawa
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Yumiko Suenaga
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Kazusa Shiotani
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Harumi Uto-Kondo
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Tomohiro Komatsu
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Kazuhiro Nakaya
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Yasuhiro Endo
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Makoto Sasaki
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
| | - Katsunori Ikewaki
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
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2
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Wculek SK, Heras-Murillo I, Mastrangelo A, Mañanes D, Galán M, Miguel V, Curtabbi A, Barbas C, Chandel NS, Enríquez JA, Lamas S, Sancho D. Oxidative phosphorylation selectively orchestrates tissue macrophage homeostasis. Immunity 2023; 56:516-530.e9. [PMID: 36738738 DOI: 10.1016/j.immuni.2023.01.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/02/2022] [Accepted: 01/12/2023] [Indexed: 02/05/2023]
Abstract
In vitro studies have associated oxidative phosphorylation (OXPHOS) with anti-inflammatory macrophages, whereas pro-inflammatory macrophages rely on glycolysis. However, the metabolic needs of macrophages in tissues (TMFs) to fulfill their homeostatic activities are incompletely understood. Here, we identified OXPHOS as the highest discriminating process among TMFs from different organs in homeostasis by analysis of RNA-seq data in both humans and mice. Impairing OXPHOS in TMFs via Tfam deletion differentially affected TMF populations. Tfam deletion resulted in reduction of alveolar macrophages (AMs) due to impaired lipid-handling capacity, leading to increased cholesterol content and cellular stress, causing cell-cycle arrest in vivo. In obesity, Tfam depletion selectively ablated pro-inflammatory lipid-handling white adipose tissue macrophages (WAT-MFs), thus preventing insulin resistance and hepatosteatosis. Hence, OXPHOS, rather than glycolysis, distinguishes TMF populations and is critical for the maintenance of TMFs with a high lipid-handling activity, including pro-inflammatory WAT-MFs. This could provide a selective therapeutic targeting tool.
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Affiliation(s)
- Stefanie K Wculek
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain.
| | - Ignacio Heras-Murillo
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain
| | - Annalaura Mastrangelo
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain
| | - Diego Mañanes
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain
| | - Miguel Galán
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain
| | - Verónica Miguel
- Program of Physiological and Pathological Processes, Centro de Biología Molecular "Severo Ochoa" (CBMSO, CSIC-UAM), 28049 Madrid, Spain
| | - Andrea Curtabbi
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain; Centro de Investigaciónes Biomédicas en Red en Fragilidad y Envejecimiento Saludabe (CIBERFES), 28029 Madrid, Spain
| | - Coral Barbas
- Centro de Metabolómica y Bioanálisis (CEMBIO), School of Pharmacy, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28660 Madrid, Spain
| | - Navdeep S Chandel
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - José Antonio Enríquez
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain; Centro de Investigaciónes Biomédicas en Red en Fragilidad y Envejecimiento Saludabe (CIBERFES), 28029 Madrid, Spain
| | - Santiago Lamas
- Program of Physiological and Pathological Processes, Centro de Biología Molecular "Severo Ochoa" (CBMSO, CSIC-UAM), 28049 Madrid, Spain
| | - David Sancho
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain.
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Zhang H, Lianto P, Li W, Xu M, Moore JB, Thorne JL. Associations between liver X receptor polymorphisms and blood lipids: A systematic review and meta-analysis. Steroids 2022; 185:109057. [PMID: 35679909 DOI: 10.1016/j.steroids.2022.109057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 04/07/2022] [Accepted: 06/02/2022] [Indexed: 12/22/2022]
Abstract
Genetic susceptibility to dyslipidaemia remains incompletely understood. The liver X receptors (LXRs), members of the nuclear receptor superfamily of ligand dependent transcription factors, are homeostatic regulators of lipid metabolism. Multiple single nucleotide polymorphisms (SNPs)have been identified previously in the coding and regulatory regions of the LXRs. The aim of this systematic review and meta-analysis was to summarise associations between SNPs of LXRs (α and β isoforms) with blood lipid and lipoprotein traits. Five databases (PubMed, Ovid Embase, Scopus, Web of Science, and the Cochrane Library) were systematically searched for population-based studies that assessed associations between one or more blood lipid/lipoprotein traits and LXR SNPs. Of seventeen articles included in the qualitative synthesis, ten were eligible for meta-analysis. Nine LXRα SNPs and five LXRβ SNPs were identified, and the three most studied LXRα SNPs were quantitatively summarised. Carriers of the minor allele A of LXRα rs12221497 (-115G>A) had higher triglyceride levels than GG homozygotes (0.13 mmol/L; 95%CI: [0.03, 0.23], P = 0.01). Heterozygote carriers of LXRα rs2279238 (297C/T) had higher total cholesterol levels (0.12 mmol/L; (95%CI: [0.01, 0.23], P = 0.04) than either CC or TT homozygotes. For LXRα rs11039155 (-6G>A), no significant differences in blood levels of either triglyceride (P = 0.39) or HDL-C (P = 0.98) were detected between genotypes in meta-analyses. In addition, there were no strong associations for other SNPs of LXRα and LXRβ. This study provides the evidence of an association between LXRα, but not LXRβ, SNPs and blood-lipid traits. Systematic review registration: PROSPERO No. CRD42021246158.
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Affiliation(s)
- Huifeng Zhang
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK; Clinical Nutrition Department, The First Affiliated Hospital of Xi'an Jiaotong University, 277 Yanta West Road, Xi'an 710061, China
| | - Priscilia Lianto
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| | - Weiming Li
- Clinical Nutrition Department, The First Affiliated Hospital of Xi'an Jiaotong University, 277 Yanta West Road, Xi'an 710061, China
| | - Mengfan Xu
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| | - J Bernadette Moore
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| | - James L Thorne
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK.
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4
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The emerging role of 27-hydroxycholesterol in cancer development and progression: An update. Int Immunopharmacol 2022; 110:109074. [DOI: 10.1016/j.intimp.2022.109074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/09/2022] [Accepted: 07/17/2022] [Indexed: 02/07/2023]
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Savla SR, Prabhavalkar KS, Bhatt LK. Liver X Receptor: a potential target in the treatment of atherosclerosis. Expert Opin Ther Targets 2022; 26:645-658. [PMID: 36003057 DOI: 10.1080/14728222.2022.2117610] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Liver X receptors (LXRs) are master regulators of atherogenesis. Their anti-atherogenic potential has been attributed to their role in the inhibition of macrophage-mediated inflammation and promotion of reverse cholesterol transport. Owing to the significance of their anti-atherogenic potential, it is essential to develop and test new generation LXR agonists, both synthetic and natural, to identify potential LXR-targeted therapeutics for the future. AREAS COVERED This review describes the role of LXRs in atherosclerotic development, provides a summary of LXR agonists and future directions for atherosclerosis research. We searched PubMed, Scopus and Google Scholar for relevant reports, from last 10 years, using atherosclerosis, liver X receptor, and LXR agonist as keywords. EXPERT OPINION LXRα has gained widespread recognition as a regulator of cholesterol homeostasis and expression of inflammatory genes. Further research using models of cell type-specific knockout and specific agonist-targeted LXR isoforms is warranted. Enthusiasm for therapeutic value of LXR agonists has been tempered due to LXRα-mediated induction of hepatic lipogenesis. LXRα agonism and LXRβ targeting, gut-specific inverse LXR agonists, investigations combining LXR agonists with other lipogenesis mitigating agents, like IDOL antagonists and synthetic HDL, and targeting ABCA1, M2 macrophages and LXRα phosphorylation, remain as promising possibilities.
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Affiliation(s)
- Shreya R Savla
- Department of Pharmacology, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai 400056, India
| | - Kedar S Prabhavalkar
- Department of Pharmacology, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai 400056, India
| | - Lokesh K Bhatt
- Department of Pharmacology, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai 400056, India
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Wculek SK, Dunphy G, Heras-Murillo I, Mastrangelo A, Sancho D. Metabolism of tissue macrophages in homeostasis and pathology. Cell Mol Immunol 2022; 19:384-408. [PMID: 34876704 PMCID: PMC8891297 DOI: 10.1038/s41423-021-00791-9] [Citation(s) in RCA: 110] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/25/2021] [Indexed: 02/06/2023] Open
Abstract
Cellular metabolism orchestrates the intricate use of tissue fuels for catabolism and anabolism to generate cellular energy and structural components. The emerging field of immunometabolism highlights the importance of cellular metabolism for the maintenance and activities of immune cells. Macrophages are embryo- or adult bone marrow-derived leukocytes that are key for healthy tissue homeostasis but can also contribute to pathologies such as metabolic syndrome, atherosclerosis, fibrosis or cancer. Macrophage metabolism has largely been studied in vitro. However, different organs contain diverse macrophage populations that specialize in distinct and often tissue-specific functions. This context specificity creates diverging metabolic challenges for tissue macrophage populations to fulfill their homeostatic roles in their particular microenvironment and conditions their response in pathological conditions. Here, we outline current knowledge on the metabolic requirements and adaptations of macrophages located in tissues during homeostasis and selected diseases.
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Affiliation(s)
- Stefanie K Wculek
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, Madrid, 28029, Spain.
| | - Gillian Dunphy
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, Madrid, 28029, Spain
| | - Ignacio Heras-Murillo
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, Madrid, 28029, Spain
| | - Annalaura Mastrangelo
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, Madrid, 28029, Spain
| | - David Sancho
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, Madrid, 28029, Spain.
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7
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Smooth muscle 22 alpha protein inhibits VSMC foam cell formation by supporting normal LXRα signaling, ameliorating atherosclerosis. Cell Death Dis 2021; 12:982. [PMID: 34686657 PMCID: PMC8536684 DOI: 10.1038/s41419-021-04239-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/11/2021] [Accepted: 09/29/2021] [Indexed: 12/31/2022]
Abstract
Vascular smooth muscle cells (VSMCs) are indispensable components in foam cell formation in atherosclerosis. However, the mechanism behind foam cell formation of VSMCs has not been addressed. We found a potential association between deletion of smooth muscle (SM) 22α and deregulated nuclear receptors liver X receptors (LXRs)/retinoid X receptor (RXR) signaling in mice. Here, we investigated the roles of SM22α in LXRα-modulated cholesterol homeostasis, and explore possible mechanisms underlying this process. We identified that the depletion of SM22α was a primary event driving VSMC cholesterol accumulation and the development of atherosclerosis in mice. Proteomic and lipidomic analysis validated that downregulation of SM22α was correlated with reduced expression of LXRα and ATP-binding cassette transporter (ABCA) 1 and increased cholesteryl ester in phenotypically modulated VSMCs induced by platelets-derived growth factor (PDGF)-BB. Notably, LXRα was mainly distributed in the cytoplasm rather than the nucleus in the neointimal and Sm22α-/- VSMCs. Loss of SM22α inhibited the nuclear import of LXRα and reduced ABCA1-mediated cholesterol efflux via promoting depolymerization of actin stress fibers. Affinity purification and mass spectrometry (AP-MS) analysis, co-immunoprecipitation and GST pull-down assays, confocal microscopy, and stochastic optical reconstruction microscopy (STORM) revealed that globular-actin (G-actin), monomeric actin, interacted with and retained LXRα in the cytoplasm in PDGF-BB-treated and Sm22α-/- VSMCs. This interaction blocked LXRα binding to Importin α, a karyopherin that mediates the trafficking of macromolecules across the nuclear envelope, and the resulting reduction of LXRα transcriptional activity. Increasing SM22α expression restored nuclear localization of LXRα and removed cholesterol accumulation via inducing actin polymerization, ameliorating atherosclerosis. Our findings highlight that LXRα is a mechanosensitive nuclear receptor and that the nuclear import of LXRα maintained by the SM22α-actin axis is a potential target for blockade of VSMC foam cell formation and development of anti-atherosclerosis.
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8
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Goel D, Vohora D. Liver X receptors and skeleton: Current state-of-knowledge. Bone 2021; 144:115807. [PMID: 33333244 DOI: 10.1016/j.bone.2020.115807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/26/2020] [Accepted: 12/11/2020] [Indexed: 12/25/2022]
Abstract
The liver X receptors (LXR) is a nuclear receptor that acts as a prominent regulator of lipid homeostasis and inflammatory response. Its therapeutic effectiveness against various diseases like Alzheimer's disease and atherosclerosis has been investigated in detail. Emerging pieces of evidence now reveal that LXR is also a crucial modulator of bone remodeling. However, the molecular mechanisms underlying the pharmacological actions of LXR on the skeleton and its role in osteoporosis are poorly understood. Therefore, in the current review, we highlight LXR and its actions through different molecular pathways modulating skeletal homeostasis. The studies described in this review propound that LXR in association with estrogen, PTH, PPARγ, RXR hedgehog, and canonical Wnt signaling regulates osteoclastogenesis and bone resorption. It regulates RANKL-induced expression of c-Fos, NFATc1, and NF-κB involved in osteoclast differentiation. Additionally, several studies suggest suppression of RANKL-induced osteoclast differentiation by synthetic LXR ligands. Given the significance of modulation of LXR in various physiological and pathological settings, our findings indicate that therapeutic targeting of LXR might potentially prevent or treat osteoporosis and improve bone quality.
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Affiliation(s)
- Divya Goel
- Department of Pharmacology, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi 110062, India
| | - Divya Vohora
- Department of Pharmacology, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi 110062, India.
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9
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Bogie JFJ, Grajchen E, Wouters E, Corrales AG, Dierckx T, Vanherle S, Mailleux J, Gervois P, Wolfs E, Dehairs J, Van Broeckhoven J, Bowman AP, Lambrichts I, Gustafsson JÅ, Remaley AT, Mulder M, Swinnen JV, Haidar M, Ellis SR, Ntambi JM, Zelcer N, Hendriks JJA. Stearoyl-CoA desaturase-1 impairs the reparative properties of macrophages and microglia in the brain. J Exp Med 2020; 217:133840. [PMID: 32097464 PMCID: PMC7201924 DOI: 10.1084/jem.20191660] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/12/2019] [Accepted: 01/24/2020] [Indexed: 12/15/2022] Open
Abstract
Failure of remyelination underlies the progressive nature of demyelinating diseases such as multiple sclerosis. Macrophages and microglia are crucially involved in the formation and repair of demyelinated lesions. Here we show that myelin uptake temporarily skewed these phagocytes toward a disease-resolving phenotype, while sustained intracellular accumulation of myelin induced a lesion-promoting phenotype. This phenotypic shift was controlled by stearoyl-CoA desaturase-1 (SCD1), an enzyme responsible for the desaturation of saturated fatty acids. Monounsaturated fatty acids generated by SCD1 reduced the surface abundance of the cholesterol efflux transporter ABCA1, which in turn promoted lipid accumulation and induced an inflammatory phagocyte phenotype. Pharmacological inhibition or phagocyte-specific deficiency of Scd1 accelerated remyelination ex vivo and in vivo. These findings identify SCD1 as a novel therapeutic target to promote remyelination.
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Affiliation(s)
- Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Elien Grajchen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Elien Wouters
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Aida Garcia Corrales
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Tess Dierckx
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Sam Vanherle
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jo Mailleux
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Pascal Gervois
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Esther Wolfs
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jonas Dehairs
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven, Belgium
| | - Jana Van Broeckhoven
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Andrew P Bowman
- The Maastricht MultiModal Molecular Imaging Institute, Division of Imaging Mass Spectrometry, Maastricht University, Maastricht, Netherlands
| | - Ivo Lambrichts
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX.,Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Alan T Remaley
- Lipoprotein Metabolism Laboratory, Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Monique Mulder
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Johannes V Swinnen
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Shane R Ellis
- The Maastricht MultiModal Molecular Imaging Institute, Division of Imaging Mass Spectrometry, Maastricht University, Maastricht, Netherlands
| | - James M Ntambi
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI.,Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | - Noam Zelcer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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10
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Fan Q, Nørgaard RC, Grytten I, Ness CM, Lucas C, Vekterud K, Soedling H, Matthews J, Lemma RB, Gabrielsen OS, Bindesbøll C, Ulven SM, Nebb HI, Grønning-Wang LM, Sæther T. LXRα Regulates ChREBPα Transactivity in a Target Gene-Specific Manner through an Agonist-Modulated LBD-LID Interaction. Cells 2020; 9:cells9051214. [PMID: 32414201 PMCID: PMC7290792 DOI: 10.3390/cells9051214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/19/2020] [Accepted: 05/07/2020] [Indexed: 01/02/2023] Open
Abstract
The cholesterol-sensing nuclear receptor liver X receptor (LXR) and the glucose-sensing transcription factor carbohydrate responsive element-binding protein (ChREBP) are central players in regulating glucose and lipid metabolism in the liver. More knowledge of their mechanistic interplay is needed to understand their role in pathological conditions like fatty liver disease and insulin resistance. In the current study, LXR and ChREBP co-occupancy was examined by analyzing ChIP-seq datasets from mice livers. LXR and ChREBP interaction was determined by Co-immunoprecipitation (CoIP) and their transactivity was assessed by real-time quantitative polymerase chain reaction (qPCR) of target genes and gene reporter assays. Chromatin binding capacity was determined by ChIP-qPCR assays. Our data show that LXRα and ChREBPα interact physically and show a high co-occupancy at regulatory regions in the mouse genome. LXRα co-activates ChREBPα and regulates ChREBP-specific target genes in vitro and in vivo. This co-activation is dependent on functional recognition elements for ChREBP but not for LXR, indicating that ChREBPα recruits LXRα to chromatin in trans. The two factors interact via their key activation domains; the low glucose inhibitory domain (LID) of ChREBPα and the ligand-binding domain (LBD) of LXRα. While unliganded LXRα co-activates ChREBPα, ligand-bound LXRα surprisingly represses ChREBPα activity on ChREBP-specific target genes. Mechanistically, this is due to a destabilized LXRα:ChREBPα interaction, leading to reduced ChREBP-binding to chromatin and restricted activation of glycolytic and lipogenic target genes. This ligand-driven molecular switch highlights an unappreciated role of LXRα in responding to nutritional cues that was overlooked due to LXR lipogenesis-promoting function.
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Affiliation(s)
- Qiong Fan
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Rikke Christine Nørgaard
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Ivar Grytten
- Department of Informatics, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway;
| | - Cecilie Maria Ness
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Christin Lucas
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Kristin Vekterud
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Helen Soedling
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Jason Matthews
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Roza Berhanu Lemma
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway; (R.B.L.); (O.S.G.)
| | - Odd Stokke Gabrielsen
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway; (R.B.L.); (O.S.G.)
| | - Christian Bindesbøll
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Stine Marie Ulven
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Hilde Irene Nebb
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Line Mariann Grønning-Wang
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Thomas Sæther
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
- Correspondence: ; Tel.: +47-22-851510
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11
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Ma C, Xia R, Yang S, Liu L, Zhang J, Feng K, Shang Y, Qu J, Li L, Chen N, Xu S, Zhang W, Mao J, Han J, Chen Y, Yang X, Duan Y, Fan G. Formononetin attenuates atherosclerosis via regulating interaction between KLF4 and SRA in apoE -/- mice. Am J Cancer Res 2020; 10:1090-1106. [PMID: 31938053 PMCID: PMC6956811 DOI: 10.7150/thno.38115] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/23/2019] [Indexed: 12/11/2022] Open
Abstract
Background and Purpose: Atherosclerosis is an underlying cause of coronary heart disease. Foam cell, a hallmark of atherosclerosis, is prominently derived from monocyte-differentiated macrophage, and vascular smooth muscle cells (VSMCs) through unlimitedly phagocytizing oxidized low-density lipoprotein (oxLDL). Therefore, the inhibition of monocyte adhesion to endothelium and uptake of oxLDL might be a breakthrough point for retarding atherosclerosis. Formononetin, an isoflavone extracted from Astragalus membranaceus, has exhibited multiple inhibitory effects on proatherogenic factors, such as obesity, dyslipidemia, and inflammation in different animal models. However, its effect on atherosclerosis remains unknown. In this study, we determined if formononetin can inhibit atherosclerosis and elucidated the underlying molecular mechanisms. Methods: ApoE deficient mice were treated with formononetin contained in high-fat diet for 16 weeks. After treatment, mouse aorta, macrophage and serum samples were collected to determine lesions, immune cell profile, lipid profile and expression of related molecules. Concurrently, we investigated the effect of formononetin on monocyte adhesion, foam cell formation, endothelial activation, and macrophage polarization in vitro and in vivo. Results: Formononetin reduced en face and aortic root sinus lesions size. Formononetin enhanced lesion stability by changing the composition of plaque. VSMC- and macrophage-derived foam cell formation and its accumulation in arterial wall were attenuated by formononetin, which might be attributed to decreased SRA expression and reduced monocyte adhesion. Formononetin inhibited atherogenic monocyte adhesion and inflammation. KLF4 negatively regulated the expression of SRA at transcriptional and translational level. Conclusions: Our study demonstrate that formononetin can substantially attenuate the development of atherosclerosis via regulation of interplay between KLF4 and SRA, which suggests the formononetin might be a novel therapeutic approach for inhibition of atherosclerosis.
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12
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Saliba-Gustafsson P, Pedrelli M, Gertow K, Werngren O, Janas V, Pourteymour S, Baldassarre D, Tremoli E, Veglia F, Rauramaa R, Smit AJ, Giral P, Kurl S, Pirro M, de Faire U, Humphries SE, Hamsten A, Gonçalves I, Orho-Melander M, Franco-Cereceda A, Borén J, Eriksson P, Magné J, Parini P, Ehrenborg E. Subclinical atherosclerosis and its progression are modulated by PLIN2 through a feed-forward loop between LXR and autophagy. J Intern Med 2019; 286:660-675. [PMID: 31251843 PMCID: PMC6899829 DOI: 10.1111/joim.12951] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Hyperlipidaemia is a major risk factor for cardiovascular disease, and atherosclerosis is the underlying cause of both myocardial infarction and stroke. We have previously shown that the Pro251 variant of perilipin-2 reduces plasma triglycerides and may therefore be beneficial to reduce atherosclerosis development. OBJECTIVE We sought to delineate putative beneficial effects of the Pro251 variant of perlipin-2 on subclinical atherosclerosis and the mechanism by which it acts. METHODS A pan-European cohort of high-risk individuals where carotid intima-media thickness has been assessed was adopted. Human primary monocyte-derived macrophages were prepared from whole blood from individuals recruited by perilipin-2 genotype or from buffy coats from the Karolinska University hospital blood central. RESULTS The Pro251 variant of perilipin-2 is associated with decreased intima-media thickness at baseline and over 30 months of follow-up. Using human primary monocyte-derived macrophages from carriers of the beneficial Pro251 variant, we show that this variant increases autophagy activity, cholesterol efflux and a controlled inflammatory response. Through extensive mechanistic studies, we demonstrate that increase in autophagy activity is accompanied with an increase in liver-X-receptor (LXR) activity and that LXR and autophagy reciprocally activate each other in a feed-forward loop, regulated by CYP27A1 and 27OH-cholesterol. CONCLUSIONS For the first time, we show that perilipin-2 affects susceptibility to human atherosclerosis through activation of autophagy and stimulation of cholesterol efflux. We demonstrate that perilipin-2 modulates levels of the LXR ligand 27OH-cholesterol and initiates a feed-forward loop where LXR and autophagy reciprocally activate each other; the mechanism by which perilipin-2 exerts its beneficial effects on subclinical atherosclerosis.
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Affiliation(s)
- P Saliba-Gustafsson
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.,Cardiovascular Medicine, Stanford University School of Medicine, Palo Alto, California, USA
| | - M Pedrelli
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet Huddinge, Huddinge, Sweden
| | - K Gertow
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - O Werngren
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - V Janas
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - S Pourteymour
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - D Baldassarre
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy.,Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - E Tremoli
- Centro Cardiologico Monzino, IRCCS, Milan, Italy.,Dipartimento di Scienze Farmacologiche e Biomolecolari, Università di Milano, Milan, Italy
| | - F Veglia
- Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - R Rauramaa
- Foundation for Research in Health Exercise and Nutrition, Kuopio Research Institute of Exercise Medicine, Kuopio, Finland
| | - A J Smit
- Department of Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - P Giral
- Assistance Publique Hopitaux de Paris, Service Endocrinologie-Metabolisme, Groupe Hospitalier Pitie-Salpetriere, Unites de Prevention Cardiovasculaire, Paris, France
| | - S Kurl
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - M Pirro
- Unit of Internal Medicine, Angiology and Arteriosclerosis Diseases, Department of Medicine, University of Perugia, Perugia, Italy
| | - U de Faire
- Division of Cardiovascular Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - S E Humphries
- Centre for Cardiovascular Genetics, Institute Cardiovascular Science, University College London, London, UK
| | - A Hamsten
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | | | - I Gonçalves
- Experimental Cardiovascular Research Group and Cardiology Department, Clinical Research Center, Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - M Orho-Melander
- Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund University, Lund, Sweden
| | - A Franco-Cereceda
- Cardiothoracic Surgery Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet at Karolinska University Hospital Solna, Solna, Sweden
| | - J Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - P Eriksson
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - J Magné
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.,St Jude Children's Research Hospital, Department of Immunology, Memphis, Tennessee, USA
| | - P Parini
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet Huddinge, Huddinge, Sweden.,Metabolism Unit, Department of Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Huddinge, Sweden
| | - E Ehrenborg
- Cardiovascular Medicine Unit, Department of Medicine, Center for Molecular Medicine at BioClinicum, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
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13
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Wang G, Huang W, Xia Y, Xiong Z, Ai L. Cholesterol-lowering potentials of Lactobacillus strain overexpression of bile salt hydrolase on high cholesterol diet-induced hypercholesterolemic mice. Food Funct 2019; 10:1684-1695. [PMID: 30839966 DOI: 10.1039/c8fo02181c] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Hypercholesterolemia is closely associated with cardiovascular disease. Supplementation with probiotics has been shown to contribute to improving lipid metabolism. The probiotic mechanisms of cholesterol reduction are complicated and remain unclear. One of the potential probiotic mechanisms for cholesterol reduction is the deconjugation of bile salts. We previously found a high bile salt hydrolase (BSH) activity of Lactobacillus casei pWQH01 (overexpression of bsh1) and Lactobacillus plantarum AR113, but found no BSH activity for Lactobacillus casei LC2W in vitro. Therefore, we decided to investigate whether the high BSH activity of L. plantarum AR113 and L. casei pWQH01 could exert a cholesterol-reducing effect in vivo. Compared to the high-cholesterol diet (HCD) group, AR113 and pWQH01 groups had a significantly lower body weight (BW), serum total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) levels and atherogenic index (AI), whereas the LC2W group had a poor capability to mitigate the blood lipid levels in the hypercholesterolemic mice. In addition, the AR113 and pWQH01 groups decreased the hepatic levels of TC and LDL-C and improved hepatic steatosis compared with the HCD group. To explore their cholesterol-lowering mechanisms of action, we determined the expression levels of these genes on the cholesterol metabolic pathways. AR113 and pWQH01 groups downregulated the expression of farnesoid X receptor (FXR) and small heterodimer partner (SHP) genes, but upregulated the expression of the cholesterol 7α-hydroxylase (CYP7A1) gene in the liver. Simultaneously, the expression of cholesterol liver X receptor (LXR) and low density lipoprotein receptor (LDLR) genes was upregulated in the liver. These results indicated that L. plantarum AR113 and L. casei pWQH01 could inhibit the cholesterol absorption and accelerate the cholesterol transportation. Taken together, these findings suggest that Lactobacillus strain overexpression of bile salt hydrolase has beneficial effects against hypercholesterolemia by reducing cholesterol absorption and increasing cholesterol catabolism.
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Affiliation(s)
- Guangqiang Wang
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
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14
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Activation of liver x receptors prevents the spinal LTP induced by skin/muscle retraction in the thigh via SIRT1/NF-Κb pathway. Neurochem Int 2019; 128:106-114. [PMID: 31018150 DOI: 10.1016/j.neuint.2019.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/03/2019] [Accepted: 04/05/2019] [Indexed: 01/31/2023]
Abstract
It has been reported that skin/muscle incision and retraction (SMIR) in the thigh, produces mechanical allodynia in the hind paw, far from the site of incision/retraction. The mechanical allodynia lasts about 22 days, indicating chronic post-operative pain develops. The precise mechanisms, however, are largely unclear. In the current study, we further found that SMIR surgery induced LTP of c-fiber evoked field potentials that lasted at least 4 h. The mRNA and protein level of tumor necrosis factor-alpha (TNFα) and acetylated nuclear factor-kappaB p65 (ac-NF-κB p65) in the lumbar spinal dorsal horn was gradually increased during LTP development, while pretreatment with either TNFα neutralization antibody or NF-κB inhibitor PDTC completely prevented the induction of LTP. Moreover, the expression of Silent information regulator 1 (SIRT1) in the lumbar spinal dorsal horn was decreased and activation of SIRT1 by SRT1720 also prevented the induction of LTP. Importantly, the spinal expression of Liver X receptors (LXRs) was increased, both at mRNA and protein level following SMIR. Application of LXRs agonist T0901317 to the spinal dorsal horn prevented LTP induction following SMIR. Mechanistically, T0901317 enhanced the expression of SIRT1 and decreased the expression of ac-NF-κB p65 and TNFα. Spinal application of SIRT1 antagonist EX-527, 30 min before T0901317 administration, completely blocked the inhibiting effect of T0901317 on LTP, and on expression of ac-NF-κB p65 and TNFα. These results indicated that activation of LXRs prevented SMIR-induced LTP by inhibiting NF-κB/TNFα pathway via increasing SIRT1 expression.
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15
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Beyond the Foam Cell: The Role of LXRs in Preventing Atherogenesis. Int J Mol Sci 2018; 19:ijms19082307. [PMID: 30087224 PMCID: PMC6121590 DOI: 10.3390/ijms19082307] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/01/2018] [Accepted: 08/02/2018] [Indexed: 12/24/2022] Open
Abstract
Atherosclerosis is a chronic condition associated with cardiovascular disease. While largely identified by the accumulation of lipid-laden foam cells within the aorta later on in life, atherosclerosis develops over several stages and decades. During atherogenesis, various cell types of the aorta acquire a pro-inflammatory phenotype that initiates the cascade of signaling events facilitating the formation of these foam cells. The liver X receptors (LXRs) are nuclear receptors that upon activation induce the expression of transporters responsible for promoting cholesterol efflux. In addition to promoting cholesterol removal from the arterial wall, LXRs have potent anti-inflammatory actions via the transcriptional repression of key pro-inflammatory cytokines. These beneficial functions sparked an interest in the potential to target LXRs and the development of agonists as anti-atherogenic agents. These early studies focused on mediating the contributions of macrophages to the underlying pathogenesis. However, further evidence has since demonstrated that LXRs reduce atherosclerosis through their actions in multiple cell types apart from those monocytes/macrophages that infiltrate the lesion. LXRs and their target genes have profound effects on multiple other cells types of the hematopoietic system. Furthermore, LXRs can also mediate dysfunction within vascular cell types of the aorta including endothelial and smooth muscle cells. Taken together, these studies demonstrate the whole-body benefits of LXR activation with respect to anti-atherogenesis, and that LXRs remain a viable target for the treatment of atherosclerosis, with a reach which extends beyond plaque macrophages.
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Abstract
The lung has a unique relationship to cholesterol that is shaped by its singular physiology. On the one hand, the lungs receive the full cardiac output and have a predominant dependence on plasma lipoprotein uptake for their cholesterol supply. On the other hand, surfactant lipids, including cholesterol, are continually susceptible to oxidation owing to direct environmental exposure and must be cleared or recycled because of the very narrow biophysical mandates placed upon surfactant lipid composition. Interestingly, increased lipid-laden macrophage "foam cells" have been noted in a wide range of human lung pathologies. This suggests that lipid dysregulation may be a unifying and perhaps contributory event in chronic lung disease pathogenesis. Recent studies have shown that perturbations in intracellular cholesterol trafficking critically modify the immune response of macrophages and other cells. This minireview discusses literature that has begun to demonstrate the importance of regulated cholesterol traffic through the lung to pulmonary immunity, inflammation, and fibrosis. This emerging recognition of coupling between immunity and lipid homeostasis in the lung presents potentially transformative concepts for understanding lung disease and may also offer novel and exciting avenues for therapeutic development.
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17
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Endo-Umeda K, Nakashima H, Komine-Aizawa S, Umeda N, Seki S, Makishima M. Liver X receptors regulate hepatic F4/80 + CD11b + Kupffer cells/macrophages and innate immune responses in mice. Sci Rep 2018; 8:9281. [PMID: 29915246 PMCID: PMC6006359 DOI: 10.1038/s41598-018-27615-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 06/07/2018] [Indexed: 12/25/2022] Open
Abstract
The liver X receptors (LXRs), LXRα and LXRβ, are nuclear receptors that regulate lipid homeostasis. LXRs also regulate inflammatory responses in cultured macrophages. However, the role of LXRs in hepatic immune cells remains poorly characterized. We investigated the role of LXRs in regulation of inflammatory responses of hepatic mononuclear cells (MNCs) in mice. Both LXRα and LXRβ were expressed in mouse hepatic MNCs and F4/80+ Kupffer cells/macrophages. LXRα/β-knockout (KO) mice had an increased number of hepatic MNCs and elevated expression of macrophage surface markers and inflammatory cytokines compared to wild-type (WT) mice. Among MNCs, F4/80+CD11b+ cells, not F4/80+CD11b- or F4/80+CD68+ cells, were increased in LXRα/β-KO mice more than WT mice. Isolated hepatic MNCs and F4/80+CD11b+ cells of LXRα/β-KO mice showed enhanced production of inflammatory cytokines after stimulation by lipopolysaccharide or CpG-DNA compared to WT cells, and LXR ligand treatment suppressed lipopolysaccharide-induced cytokine expression in hepatic MNCs. Lipopolysaccharide administration also stimulated inflammatory cytokine production in LXRα/β-KO mice more effectively than WT mice. Thus, LXR deletion enhances recruitment of F4/80+CD11b+ Kupffer cells/macrophages and acute immune responses in the liver. LXRs regulate the Kupffer cell/macrophage population and innate immune and inflammatory responses in mouse liver.
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Affiliation(s)
- Kaori Endo-Umeda
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Hiroyuki Nakashima
- Department of Immunology and Microbiology, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan
| | - Shihoko Komine-Aizawa
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Naoki Umeda
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Shuhji Seki
- Department of Immunology and Microbiology, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan
| | - Makoto Makishima
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan.
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18
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Zhang L, Rajbhandari P, Priest C, Sandhu J, Wu X, Temel R, Castrillo A, de Aguiar Vallim TQ, Sallam T, Tontonoz P. Inhibition of cholesterol biosynthesis through RNF145-dependent ubiquitination of SCAP. eLife 2017; 6:e28766. [PMID: 29068315 PMCID: PMC5656429 DOI: 10.7554/elife.28766] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 10/05/2017] [Indexed: 12/25/2022] Open
Abstract
Cholesterol homeostasis is maintained through concerted action of the SREBPs and LXRs. Here, we report that RNF145, a previously uncharacterized ER membrane ubiquitin ligase, participates in crosstalk between these critical signaling pathways. RNF145 expression is induced in response to LXR activation and high-cholesterol diet feeding. Transduction of RNF145 into mouse liver inhibits the expression of genes involved in cholesterol biosynthesis and reduces plasma cholesterol levels. Conversely, acute suppression of RNF145 via shRNA-mediated knockdown, or chronic inactivation of RNF145 by genetic deletion, potentiates the expression of cholesterol biosynthetic genes and increases cholesterol levels both in liver and plasma. Mechanistic studies show that RNF145 triggers ubiquitination of SCAP on lysine residues within a cytoplasmic loop essential for COPII binding, potentially inhibiting its transport to Golgi and subsequent processing of SREBP-2. These findings define an additional mechanism linking hepatic sterol levels to the reciprocal actions of the SREBP-2 and LXR pathways.
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Affiliation(s)
- Li Zhang
- Department of Pathology and Laboratory MedicineHoward Hughes Medical Institute, University of California, Los AngelesLos AngelesUnited States
| | - Prashant Rajbhandari
- Department of Pathology and Laboratory MedicineHoward Hughes Medical Institute, University of California, Los AngelesLos AngelesUnited States
| | - Christina Priest
- Department of Pathology and Laboratory MedicineHoward Hughes Medical Institute, University of California, Los AngelesLos AngelesUnited States
| | - Jaspreet Sandhu
- Department of Pathology and Laboratory MedicineHoward Hughes Medical Institute, University of California, Los AngelesLos AngelesUnited States
| | - Xiaohui Wu
- Department of Medicine, Division of CardiologyUniversity of California, Los AngelesLos AngelesUnited States
| | - Ryan Temel
- Saha Cardiovascular Research CenterUniversity of KentuckyLexingtonUnited States
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonUnited States
| | - Antonio Castrillo
- Instituto de Investigaciones Biomédicas Alberto SolsCSIC-Universidad Autónoma de Madrid, Unidad de Biomedicina-Universidad de Las Palmas de Gran Canaria (Unidad asociada al CSIC)Las Palmas de Gran CanariaSpain
- Instituto Universitario de Investigaciones Biomédicas y SanitariasUniversidad de Las Palmas de Gran CanariaLas Palmas de Gran CanariaSpain
| | - Thomas Q de Aguiar Vallim
- Department of Medicine, Division of CardiologyUniversity of California, Los AngelesLos AngelesUnited States
| | - Tamer Sallam
- Department of Medicine, Division of CardiologyUniversity of California, Los AngelesLos AngelesUnited States
| | - Peter Tontonoz
- Department of Pathology and Laboratory MedicineHoward Hughes Medical Institute, University of California, Los AngelesLos AngelesUnited States
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19
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Functional diversity of macrophages in vascular biology and disease. Vascul Pharmacol 2017; 99:13-22. [PMID: 29074468 DOI: 10.1016/j.vph.2017.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 10/19/2017] [Indexed: 12/24/2022]
Abstract
Atherosclerosis is a multifactorial chronic inflammatory disease and is largely responsible for cardiovascular disease, the most common cause of global mortality. The hallmark of atherogenesis is immune activation following lipid accumulation in the arterial wall. In particular, macrophages play a non-redundant role in both the progression and regression of inflammation in the atherosclerotic lesion. Macrophages are remarkably heterogeneous phagocytes that perform versatile functions in health and disease. Their functional diversity in vascular biology is only partially mapped. Targeting macrophages is often highlighted as a therapeutic approach for cancer, metabolic and inflammatory diseases. Future strategies for therapeutic intervention in atherosclerosis may benefit from attempts to reduce local proliferation of pro-inflammatory macrophage subsets or enhance resolution of inflammation. Thus, characterisation of macrophage subsets during atherosclerosis would empower clinical interventions. Therefore, it would be of fundamental importance to understand how pathological factors modulate macrophage activity in order to exploit their use in the treatment of atherosclerosis and other diseases.
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Li Z, Martin M, Zhang J, Huang HY, Bai L, Zhang J, Kang J, He M, Li J, Maurya MR, Gupta S, Zhou G, Sangwung P, Xu YJ, Lei T, Huang HD, Jain M, Jain MK, Subramaniam S, Shyy JYJ. Krüppel-Like Factor 4 Regulation of Cholesterol-25-Hydroxylase and Liver X Receptor Mitigates Atherosclerosis Susceptibility. Circulation 2017; 136:1315-1330. [PMID: 28794002 DOI: 10.1161/circulationaha.117.027462] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 07/31/2017] [Indexed: 12/30/2022]
Abstract
BACKGROUND Atherosclerosis is a multifaceted inflammatory disease involving cells in the vascular wall (eg, endothelial cells [ECs]), as well as circulating and resident immunogenic cells (eg, monocytes/macrophages). Acting as a ligand for liver X receptor (LXR), but an inhibitor of SREBP2 (sterol regulatory element-binding protein 2), 25-hydroxycholesterol, and its catalyzing enzyme cholesterol-25-hydroxylase (Ch25h) are important in regulating cellular inflammatory status and cholesterol biosynthesis in both ECs and monocytes/macrophages. METHODS Bioinformatic analyses were used to investigate RNA-sequencing data to identify cholesterol oxidation and efflux genes regulated by Krüppel-like factor 4 (KLF4). In vitro experiments involving cultured ECs and macrophages and in vivo methods involving mice with Ch25h ablation were then used to explore the atheroprotective role of KLF4-Ch25h/LXR. RESULTS Vasoprotective stimuli increased the expression of Ch25h and LXR via KLF4. The KLF4-Ch25h/LXR homeostatic axis functions through suppressing inflammation, evidenced by the reduction of inflammasome activity in ECs and the promotion of M1 to M2 phenotypic transition in macrophages. The increased atherosclerosis in apolipoprotein E-/-/Ch25h-/- mice further demonstrates the beneficial role of the KLF4-Ch25h/LXR axis in vascular function and disease. CONCLUSIONS KLF4 transactivates Ch25h and LXR, thereby promoting the synergistic effects between ECs and macrophages to protect against atherosclerosis susceptibility.
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Affiliation(s)
- Zhao Li
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Marcy Martin
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Jin Zhang
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Hsi-Yuan Huang
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Liang Bai
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Jiao Zhang
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Jian Kang
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Ming He
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Jie Li
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Mano R Maurya
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Shakti Gupta
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Guangjin Zhou
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Panjamaporn Sangwung
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Yong-Jiang Xu
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Ting Lei
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Hsien-Da Huang
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Mohit Jain
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Mukesh K Jain
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - Shankar Subramaniam
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.)
| | - John Y-J Shyy
- From Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China (Z.L., Jin Zhang, L.B., Jiao Zhang, M.H., J.L., T.L., J.Y.-J.S.); Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla (M.M., Jin Zhang, J.K., M.H., Y.-J.X., M.J., J.Y.-J.S.);Department of Bioengineering, University of California, San Diego, La Jolla (M.R.M., S.G.); Division of Biochemistry and Molecular Biology, University of California, Riverside (M.M.); Institute of Bioinformatics and Systems Biology and Department of Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan (H.-Y.H., H.-D.H.); and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH (G.Z., P.S., M.K.J.).
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21
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Feng C, Li D, Jiang L, Liu X, Li Q, Geng C, Sun X, Yang G, Yao X, Chen M. Citreoviridin induces triglyceride accumulation in hepatocytes through inhibiting PPAR-α in vivo and in vitro. Chem Biol Interact 2017. [PMID: 28645467 DOI: 10.1016/j.cbi.2017.06.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Citreoviridin (CIT) is a mycotoxin produced by Penicillum citreonigrum, Aspergillus terreus and Eupenicillium ochrosalmoneum. CIT occurs naturally in moldy rice and corn. CIT is associated with the development of atherosclerosis in the general population. Alteration in hepatic lipid metabolism is a pathogenic factor in atherosclerosis. However the effect and the underlying mechanism of CIT on hepatic lipid metabolism are largely unknown. In this study, we reported that CIT induced triglyceride accumulation in mice liver and human liver HepG2 cells as shown in oil red O staining. CIT (0.1 mg/kg-0.3 mg/kg) for 6 weeks elevated liver triglyceride contents in mice. CIT inhibited the transactivation activity of peroxisome proliferator-activated receptor-α (PPAR-α) in hepatocyte in vivo and in vitro, as shown by the reduced mRNA levels of PPAR-α target genes which play key roles in lipid metabolism in various aspects. PPAR-α agonist fenofibrate attenuated CIT-induced triglyceride accumulation in HepG2 cells. Furthermore, CIT increased serum total cholesterol/high-density lipoprotein cholesterol ratio, a strong risk factor for cardiovascular disease. In summary, we reported that CIT induced PPAR-α-dependent hepatic triglyceride accumulation and dyslipidemia. Our data will provide new mechanistic insights into CIT-induced lipid alterations.
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Affiliation(s)
- Chang Feng
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Dandan Li
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Liping Jiang
- Liaoning Anti-Degenerative Diseases Natural Products Engineering Research Center, Dalian Medical University, Dalian, China
| | - Xiaofang Liu
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Qiujuan Li
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Chengyan Geng
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Xiance Sun
- Department of Preventive Medicine, Dalian Medical University, Dalian, China; Liaoning Anti-Degenerative Diseases Natural Products Engineering Research Center, Dalian Medical University, Dalian, China
| | - Guang Yang
- Department of Preventive Medicine, Dalian Medical University, Dalian, China
| | - Xiaofeng Yao
- Department of Preventive Medicine, Dalian Medical University, Dalian, China; Department of Medicine, University of California San Diego, La Jolla, United States.
| | - Min Chen
- Department of Preventive Medicine, Dalian Medical University, Dalian, China.
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22
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Vermeulen I, Baird M, Al-Dulayymi J, Smet M, Verschoor J, Grooten J. Mycolates of Mycobacterium tuberculosis modulate the flow of cholesterol for bacillary proliferation in murine macrophages. J Lipid Res 2017; 58:709-718. [PMID: 28193630 DOI: 10.1194/jlr.m073171] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 01/28/2017] [Indexed: 12/11/2022] Open
Abstract
The differentiation of macrophages into lipid-filled foam cells is a hallmark of the lung granuloma that forms in patients with active tuberculosis (TB). Mycolic acids (MAs), the abundant lipid virulence factors in the cell wall of Mycobacterium tuberculosis (Mtb), can induce this foam phenotype possibly as a way to perturb host cell lipid homeostasis to support the infection. It is not exactly clear how MAs allow differentiation of foam cells during Mtb infection. Here we investigated how chemically synthetic MAs, each with a defined stereochemistry similar to natural Mtb-associated mycolates, influence cell foamy phenotype and mycobacterial proliferation in murine host macrophages. Using light and laser-scanning-confocal microscopy, we assessed the influence of MA structure first on the induction of granuloma cell types, second on intracellular cholesterol accumulation, and finally on mycobacterial growth. While methoxy-MAs (mMAs) effected multi-vacuolar giant cell formation, keto-MAs (kMAs) induced abundant intracellular lipid droplets that were packed with esterified cholesterol. Macrophages from mice treated with kMA were permissive to mycobacterial growth, whereas cells from mMA treatment were not. This suggests a separate yet key involvement of oxygenated MAs in manipulating host cell lipid homeostasis to establish the state of TB.
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Affiliation(s)
- Ilke Vermeulen
- Laboratory of Molecular Immunology, Department of Biomedical Molecular Biology, Ghent University, Ghent Zwijnaarde 9052, Belgium; Department of Biochemistry, University of Pretoria, Pretoria 0002, South Africa
| | - Mark Baird
- School of Chemistry, Bangor University, Bangor LL57 2UW, United Kingdom
| | - Juma Al-Dulayymi
- School of Chemistry, Bangor University, Bangor LL57 2UW, United Kingdom
| | - Muriel Smet
- Laboratory of Molecular Immunology, Department of Biomedical Molecular Biology, Ghent University, Ghent Zwijnaarde 9052, Belgium
| | - Jan Verschoor
- Department of Biochemistry, University of Pretoria, Pretoria 0002, South Africa
| | - Johan Grooten
- Laboratory of Molecular Immunology, Department of Biomedical Molecular Biology, Ghent University, Ghent Zwijnaarde 9052, Belgium.
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23
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Li N, Wang X, Xu Y, Lin Y, Zhu N, Liu P, Lu D, Si S. Identification of a Novel Liver X Receptor Agonist that Regulates the Expression of Key Cholesterol Homeostasis Genes with Distinct Pharmacological Characteristics. Mol Pharmacol 2017; 91:264-276. [PMID: 28087808 DOI: 10.1124/mol.116.105213] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 01/06/2017] [Indexed: 11/22/2022] Open
Abstract
Activation of liver X receptor (LXR) is associated with cholesterol metabolism and anti-inflammatory processes, which makes it beneficial to antiatherosclerosis therapy. Nevertheless, existing agonists that target LXR, for example TO901317, are related to unwanted side effects. In the present study, using a screening method we identified IMB-808, which displayed potent dual LXRα/β agonistic activity. In vitro, IMB-808 effectively increased the expressing quantity of genes related to reverse cholesterol transport process as well as those associated with cholesterol metabolism pathway in multiple cell lines. Additionally, IMB-808 remarkably promoted cholesterol efflux from RAW264.7 as well as THP-1 macrophage cells and reduced cellular lipid accumulation accordingly. Interestingly, compared with TO901317, IMB-808 almost did not increase the expressing quantity of genes related to lipogenesis in HepG2 cells, which indicated that IMB-808 could exhibit fewer internal lipogenic side effects with a characteristic of selective LXR agonist. Furthermore, in comparison with the full LXR agonist TO901317, IMB-808 recruits coregulators differently and possesses a distinct predictive binding pattern for the LXR ligand-binding domain. In summary, our study demonstrated that IMB-808 could act as an innovative partial LXR agonist that avoids common lipogenic side effects, providing insight for the design of novel LXR modulators. Our data indicate that this compound might be used as a promising therapeutic agent for the prospective treatment of atherosclerosis in the future.
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Affiliation(s)
- Ni Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Xiao Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Yanni Xu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Yuan Lin
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Ningyu Zhu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Peng Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Duo Lu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
| | - Shuyi Si
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (N.L., Y.L., D.L.); and Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China (N.L., X.W., Y.X., N.Z., P.L., S.S.)
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Su W, Huang SZ, Gao M, Kong XM, Gustafsson JÅ, Xu SJ, Wang B, Zheng F, Chen LH, Wang NP, Guan YF, Zhang XY. Liver X receptor β increases aquaporin 2 protein level via a posttranscriptional mechanism in renal collecting ducts. Am J Physiol Renal Physiol 2017; 312:F619-F628. [PMID: 28052875 DOI: 10.1152/ajprenal.00564.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/19/2016] [Accepted: 12/27/2016] [Indexed: 01/22/2023] Open
Abstract
Liver X receptors (LXRs) including LXRα and LXRβ are nuclear receptor transcription factors and play an important role in lipid and glucose metabolism. It has been previously reported that mice lacking LXRβ but not LXRα develop a severe urine concentrating defect, likely via a central mechanism. Here we provide evidence that LXRβ regulates water homeostasis through increasing aquaporin 2 (AQP2) protein levels in renal collecting ducts. LXRβ-/- mice exhibited a reduced response to desmopressin (dDAVP) stimulation, suggesting that the diabetes insipidus phenotype is of both central and nephrogenic origin. AQP2 protein abundance in the renal inner medulla was significantly reduced in LXRβ-/- mice but with little change in AQP2 mRNA levels. In vitro studies showed that AQP2 protein levels were elevated upon LXR agonist treatment in both primary cultured mouse inner medullary duct cells (mIMCD) and the mIMCD3 cell line with stably expressed AQP2. In addition, LXR agonists including TO901317 and GW3965 failed to induce AQP2 gene transcription but diminished its protein ubiquitination in primary cultured mIMCD cells, thereby inhibiting its degradation. Moreover, LXR activation-induced AQP2 protein expression was abolished by the protease inhibitor MG132 and the ubiquitination-deficient AQP2 (K270R). Taken together, the present study demonstrates that activation of LXRβ increases AQP2 protein levels in the renal collecting ducts via a posttranscriptional mechanism. As such, LXRβ represents a key regulator of body water homeostasis.
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Affiliation(s)
- Wen Su
- AstraZeneca-Shenzhen University Joint Institute of Nephrology, Shenzhen University Health Science Center, Shenzhen University, Shenzhen, China
| | - Shi-Zheng Huang
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
| | - Min Gao
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
| | - Xiao-Mu Kong
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas.,Center for Biosciences, Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Stockholm, Sweden; and
| | - Su-Juan Xu
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Bing Wang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Feng Zheng
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Li-Hong Chen
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Nan-Ping Wang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - You-Fei Guan
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Xiao-Yan Zhang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
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25
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Cheng TJ, Lin SW, Chen CW, Guo HR, Wang YJ. Arsenic trioxide suppresses liver X receptor β and enhances cholesteryl ester transfer protein expression without affecting the liver X receptor α in HepG2 cells. Chem Biol Interact 2016; 258:288-96. [PMID: 27622732 DOI: 10.1016/j.cbi.2016.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 08/21/2016] [Accepted: 09/09/2016] [Indexed: 12/12/2022]
Abstract
Chronic arsenic exposure is associated with cerebrovascular disease and the formation of atherosclerotic lesions. Our previous study demonstrated that arsenic trioxide (ATO) exposure was associated with atherosclerotic lesion formation through alterations in lipid metabolism in the reverse cholesterol transport process. In mouse livers, the expression of the liver X receptor β (LXR-β) and the cholesteryl ester transfer protein (CETP) was suppressed without any changes to the lipid profile. The aim of this study was to elucidate whether ATO contributes to atherosclerotic lesions by suppressing LXR-β and CETP levels in hepatocytes. HepG2 cells, human hepatocytes, were exposed to different ATO concentrations in vitro. Cell viability was determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. The liver X receptor α (LXR-α), LXR-β, sterol regulatory element-binding protein-1c (SREBP-1c) and CETP protein levels were measured by Western blotting, and their mRNA levels were measured by real-time PCR. Cholesterol efflux was analyzed by flow cytometry. The results showed ATO inhibited LXR-β mRNA and protein levels with a subsequent decrease in SREBP-1c protein levels and reduced cholesterol efflux from HepG2 cells into the extracellular space without influencing LXR-α mRNA and protein levels. CETP protein levels of HepG2 cells were significantly elevated under arsenic exposure. Transfection of LXR-β shRNA did not change CETP protein levels, implying that there is no cross-talk between LXR-β and CETP. In conclusion, arsenic not only inhibits LXR-β and SREBP-1c mRNA and protein levels but also independently increases CETP protein levels in HepG2 cells.
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Affiliation(s)
- Tain-Junn Cheng
- Department of Neurology and Occupational Medicine, Chi Mei Medical Center, 901 Zhonghua Road, Yongkang Dist., Tainan 710, Taiwan; Department of Occupational Safety and Health/Institute of Industrial Safety and Disaster Prevention, College of Sustainable Environment, Chia Nan University of Pharmacy and Science, 60 Sec. 1, Erren Road, Rende Dist., Tainan 71710, Taiwan
| | - Shu-Wen Lin
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan 704, Taiwan
| | - Chih-Wei Chen
- Department of Occupational Safety and Health/Institute of Industrial Safety and Disaster Prevention, College of Sustainable Environment, Chia Nan University of Pharmacy and Science, 60 Sec. 1, Erren Road, Rende Dist., Tainan 71710, Taiwan; Division of Neurosurgery, Department of Surgery, Chi Mei Medical Center, 901 Zhonghua Road, Yongkang Dist., Tainan 710, Taiwan
| | - How-Ran Guo
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan 704, Taiwan; Department of Occupational and Environmental Medicine, National Cheng Kung University Hospital, 138 Sheng-Li Road, Tainan 704, Taiwan.
| | - Ying-Jang Wang
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan 704, Taiwan; Department of Biomedical and Informatics, Asia University, 500 Lioufeng Road, Wufeng, Taichung, 41354, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, 500 Lioufeng Road, Wufeng, Taichung, 41354, Taiwan.
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26
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Liver X receptors regulate cerebrospinal fluid production. Mol Psychiatry 2016; 21:844-56. [PMID: 26324101 DOI: 10.1038/mp.2015.133] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 07/23/2015] [Accepted: 07/28/2015] [Indexed: 11/08/2022]
Abstract
Of the two isoforms of Liver X receptor (LXR), LXRβ has been shown to have major effects in the central nervous system (CNS) and on the regulation of aquaporins while LXRα has its most marked effects on cholesterol homeostasis. Both receptors have immunomodulatory functions. In LXRαβ knockout (ko) mice, the CNS phenotype is much more severe than in the LXRβ ko mice, suggesting a contribution of LXRα in CNS functions. One of the most striking abnormalities in the brains of LXRαβ ko mice is the occlusion of the lateral ventricles with age. In the present study, we have found by immunohistochemical staining that both LXRα and LXRβ are expressed in the cell nuclei of the epithelium of the choroid plexus and in the ependymal cells surrounding the lateral ventricles. The two receptors regulate several genes and can compensate for each other on expression of genes involved in structural integrity (E-cadherin, P-cadherin and β-catenin) and function (aquaporin 1 and carbonic anhydrase IX). Aquaporin 4 (AQ4) is not expressed in the choroid plexus but is expressed in the astrocytic end feet and ependymal cells. AQP4 expression was increased in white matter around lateral ventricles but not in neurons of LXRαβ ko mice. The data show that LXR is a regulator of cerebrospinal fluid (CSF) both at the choroid plexus and at the astrocytic end feet and defects in the synthesis of cerebrospinal fluid may be targeted by LXR agonists to facilitate CSF production, turnover and clearance in CNS diseases.
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27
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Cannon MV, Silljé HHW, Sijbesma JWA, Vreeswijk-Baudoin I, Ciapaite J, van der Sluis B, van Deursen J, Silva GJJ, de Windt LJ, Gustafsson JÅ, van der Harst P, van Gilst WH, de Boer RA. Cardiac LXRα protects against pathological cardiac hypertrophy and dysfunction by enhancing glucose uptake and utilization. EMBO Mol Med 2016; 7:1229-43. [PMID: 26160456 PMCID: PMC4568954 DOI: 10.15252/emmm.201404669] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Pathological cardiac hypertrophy is characterized by a shift in metabolic substrate utilization from fatty acids to glucose, but the molecular events underlying the metabolic remodeling remain poorly understood. Here, we investigated the role of liver X receptors (LXRs), which are key regulators of glucose and lipid metabolism, in cardiac hypertrophic pathogenesis. Using a transgenic approach in mice, we show that overexpression of LXRα acts to protect the heart against hypertrophy, fibrosis, and dysfunction. Gene expression profiling studies revealed that genes regulating metabolic pathways were differentially expressed in hearts with elevated LXRα. Functionally, LXRα overexpression in isolated cardiomyocytes and murine hearts markedly enhanced the capacity for myocardial glucose uptake following hypertrophic stress. Conversely, this adaptive response was diminished in LXRα-deficient mice. Transcriptional changes induced by LXRα overexpression promoted energy-independent utilization of glucose via the hexosamine biosynthesis pathway, resulting in O-GlcNAc modification of GATA4 and Mef2c and the induction of cytoprotective natriuretic peptide expression. Our results identify LXRα as a key cardiac transcriptional regulator that helps orchestrate an adaptive metabolic response to chronic cardiac stress, and suggest that modulating LXRα may provide a unique opportunity for intervening in myocyte metabolism.
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Affiliation(s)
- Megan V Cannon
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Herman H W Silljé
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jürgen W A Sijbesma
- Department of Nuclear Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Inge Vreeswijk-Baudoin
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jolita Ciapaite
- Department Pediatrics, Center for Liver, Digestive and Metabolic Diseases, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Bart van der Sluis
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan van Deursen
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Gustavo J J Silva
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Leon J de Windt
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Jan-Åke Gustafsson
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge, Sweden
| | - Pim van der Harst
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Wiek H van Gilst
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Rudolf A de Boer
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Matsushita K, Morello F, Zhang Z, Masuda T, Iwanaga S, Steffensen KR, Gustafsson JÅ, Pratt RE, Dzau VJ. Nuclear hormone receptor LXRα inhibits adipocyte differentiation of mesenchymal stem cells with Wnt/beta-catenin signaling. J Transl Med 2016; 96:230-8. [PMID: 26595172 PMCID: PMC4731266 DOI: 10.1038/labinvest.2015.141] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/31/2015] [Accepted: 08/15/2015] [Indexed: 01/15/2023] Open
Abstract
Nuclear hormone receptor liver X receptor-alpha (LXRα) has a vital role in cholesterol homeostasis and is reported to have a role in adipose function and obesity although this is controversial. Conversely, mesenchymal stem cells (MSCs) are suggested to be a major source of adipocyte generation. Accordingly, we examined the role of LXRα in adipogenesis of MSCs. Adult murine MSCs (mMSCs) were isolated from wild-type (WT) and LXR-null mice. Using WT mMSCs, we further generated cell lines stably overexpressing GFP-LXRα (mMSC/LXRα/GFP) or GFP alone (mMSC/GFP) by retroviral infection. Confluent mMSCs were differentiated into adipocytes by the established protocol. Compared with MSCs isolated from WT mice, MSCs from LXR-null mice showed significantly increased adipogenesis, as determined by lipid droplet accumulation and adipogenesis-related gene expression. Moreover, mMSCs stably overexpressing GFP-LXRα (mMSC/LXRα/GFP) exhibited significantly decreased adipogenesis compared with mMSCs overexpressing GFP alone (mMSC/GFP). Since Wnt/beta-catenin signaling is reported to inhibit adipogenesis, we further examined it. The LXR-null group showed significantly decreased Wnt expression accompanied by a decrease of cellular beta-catenin (vs WT). The mMSC/LXRα/GFP group exhibited significantly increased Wnt expression accompanied by an increase of cellular beta-catenin (vs mMSC/GFP). These data demonstrate that LXRα has an inhibitory effect on adipogenic differentiation in mMSCs with Wnt/beta-catenin signaling. These results provide important insights into the pathophysiology of obesity and obesity-related consequences such as metabolic syndrome and may identify potential therapeutic targets.
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Affiliation(s)
- Kenichi Matsushita
- Department of Medicine, Duke University Medical Center, GSRB II Bldg., Durham, NC 27710, USA,Second Department of Internal Medicine, Kyorin University School of Medicine, Tokyo 181-8611, Japan
| | - Fulvio Morello
- Department of Medicine, Duke University Medical Center, GSRB II Bldg., Durham, NC 27710, USA
| | - Zhiping Zhang
- Department of Medicine, Duke University Medical Center, GSRB II Bldg., Durham, NC 27710, USA
| | - Tomoko Masuda
- Department of Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Shiro Iwanaga
- Department of Cardiology, Saitama Medical University and Saitama International Medical Center, Saitama 350-1298, Japan
| | - Knut R. Steffensen
- Department of Bioscience and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Jan-Åke Gustafsson
- Department of Bioscience and Nutrition, Karolinska Institutet, Huddinge, Sweden,Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
| | - Richard E. Pratt
- Department of Medicine, Duke University Medical Center, GSRB II Bldg., Durham, NC 27710, USA
| | - Victor J. Dzau
- Department of Medicine, Duke University Medical Center, GSRB II Bldg., Durham, NC 27710, USA,Institute of Medicine, 500 Fifth St NW, Washington, DC 20001, USA
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Emerging role of liver X receptors in cardiac pathophysiology and heart failure. Basic Res Cardiol 2015; 111:3. [PMID: 26611207 PMCID: PMC4661180 DOI: 10.1007/s00395-015-0520-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/03/2015] [Indexed: 01/09/2023]
Abstract
Liver X receptors (LXRs) are master regulators of metabolism and have been studied for their pharmacological potential in vascular and metabolic disease. Besides their established role in metabolic homeostasis and disease, there is mounting evidence to suggest that LXRs may exert direct beneficial effects in the heart. Here, we aim to provide a conceptual framework to explain the broad mode of action of LXRs and how LXR signaling may be an important local and systemic target for the treatment of heart failure. We discuss the potential role of LXRs in systemic conditions associated with heart failure, such as hypertension, diabetes, and renal and vascular disease. Further, we expound on recent data that implicate a direct role for LXR activation in the heart, for its impact on cardiomyocyte damage and loss due to ischemia, and effects on cardiac hypertrophy, fibrosis, and myocardial metabolism. Taken together, the accumulating evidence supports the notion that LXRs may represent a novel therapeutic target for the treatment of heart failure.
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30
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Inflammation-induced foam cell formation in chronic inflammatory disease. Immunol Cell Biol 2015; 93:683-93. [PMID: 25753272 DOI: 10.1038/icb.2015.26] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/21/2015] [Accepted: 02/04/2015] [Indexed: 12/20/2022]
Abstract
Atherosclerosis is the leading cause of cardiovascular disease and is both a metabolic and inflammatory disease. Two models describe early events initiating atherosclerotic plaque formation, whereby foam cells form in response to hyperlipidaemia or inflammation-associated stimuli. Although these models are inextricably linked and not mutually exclusive, identifying the unique contribution of each in different disease settings remains an important question. Circulating monocytes are key mediators of atherogenesis in both models as precursors to lipid-laden foam cells formed in response to either excess lipid deposition in arteries, signalling via pattern-associated molecular patterns or a combination of the two. In this review, we assess the role of monocytes in each model and discuss how key steps in atherogenesis may be targeted to enhance clinical outcomes in patients with chronic inflammatory disease.
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31
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Bindesbøll C, Fan Q, Nørgaard RC, MacPherson L, Ruan HB, Wu J, Pedersen TÅ, Steffensen KR, Yang X, Matthews J, Mandrup S, Nebb HI, Grønning-Wang LM. Liver X receptor regulates hepatic nuclear O-GlcNAc signaling and carbohydrate responsive element-binding protein activity. J Lipid Res 2015; 56:771-85. [PMID: 25724563 DOI: 10.1194/jlr.m049130] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Liver X receptor (LXR)α and LXRβ play key roles in hepatic de novo lipogenesis through their regulation of lipogenic genes, including sterol regulatory element-binding protein (SREBP)-1c and carbohydrate responsive element-binding protein (ChREBP). LXRs activate lipogenic gene transcription in response to feeding, which is believed to be mediated by insulin. We have previously shown that LXRs are targets for glucose-hexosamine-derived O-linked β-N-acetylglucosamine (O-GlcNAc) modification enhancing their ability to regulate SREBP-1c promoter activity in vitro. To elucidate insulin-independent effects of feeding on LXR-mediated lipogenic gene expression in vivo, we subjected control and streptozotocin-treated LXRα/β(+/+) and LXRα/β(-/-) mice to a fasting-refeeding regime. We show that under hyperglycemic and hypoinsulinemic conditions, LXRs maintain their ability to upregulate the expression of glycolytic and lipogenic enzymes, including glucokinase (GK), SREBP-1c, ChREBPα, and the newly identified shorter isoform ChREBPβ. Furthermore, glucose-dependent increases in LXR/retinoid X receptor-regulated luciferase activity driven by the ChREBPα promoter was mediated, at least in part, by O-GlcNAc transferase (OGT) signaling in Huh7 cells. Moreover, we show that LXR and OGT interact and colocalize in the nucleus and that loss of LXRs profoundly reduced nuclear O-GlcNAc signaling and ChREBPα promoter binding activity in vivo. In summary, our study provides evidence that LXRs act as nutrient and glucose metabolic sensors upstream of ChREBP by modulating GK expression, nuclear O-GlcNAc signaling, and ChREBP expression and activity.
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Affiliation(s)
- Christian Bindesbøll
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway
| | - Qiong Fan
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway
| | - Rikke C Nørgaard
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway
| | - Laura MacPherson
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario M5S1A8, Canada
| | - Hai-Bin Ruan
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06519 Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06519
| | - Jing Wu
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06519 Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06519
| | - Thomas Å Pedersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Knut R Steffensen
- Division of Clinical Chemistry Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, C174, SE-141 86 Stockholm, Sweden
| | - Xiaoyong Yang
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06519 Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06519 Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06519
| | - Jason Matthews
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario M5S1A8, Canada
| | - Susanne Mandrup
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Hilde I Nebb
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway
| | - Line M Grønning-Wang
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, N-0316 Oslo, Norway
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32
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Lemaire M, Lemarié CA, Flores Molina M, Guilbert C, Lehoux S, Mann KK. Genetic deletion of LXRα prevents arsenic-enhanced atherosclerosis, but not arsenic-altered plaque composition. Toxicol Sci 2014; 142:477-88. [PMID: 25273567 DOI: 10.1093/toxsci/kfu197] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Arsenic exposure has been linked to an increased incidence of atherosclerosis. Previously, we have shown in vitro and in vivo that arsenic inhibits transcriptional activation of the liver X receptors (LXRs), key regulators of lipid homeostasis. Therefore, we evaluated the role of LXRα in arsenic-induced atherosclerosis using the apoE(-/-) mouse model. Indeed, deletion of LXRα protected apoE(-/-) mice against the proatherogenic effects of arsenic. We have previously shown that arsenic changes the plaque composition in apoE(-/-) mice. Arsenic decreased collagen content in the apoE(-/-) model, and we have observed the same diminution in LXRα(-/-)apoE(-/-) mice. However, the collagen-producing smooth muscle cells (SMCs) were decreased in apoE(-/-), but increased in LXRα(-/-)apoE(-/-). Although transcriptional activation of collagen remained the same in SMC from both genotypes, arsenic-exposed LXRα(-/-)apoE(-/-) plaques had increased matrix metalloproteinase activity compared with both control LXRα(-/-)apoE(-/-) and apoE(-/-), which could be responsible for both the decrease in plaque collagen and the SMC invasion. In addition, arsenic increased plaque lipid accumulation in both genotypes. However, macrophages, the cells known to retain lipid within the plaque, were unchanged in arsenic-exposed apoE(-/-) mice, but decreased in LXRα(-/-)apoE(-/-). We confirmed in vitro that these cells retained more lipid following arsenic exposure and are more sensitive to apoptosis than apoE(-/-). Mice lacking LXRα are resistant to arsenic-enhanced atherosclerosis, but arsenic-exposed LXRα(-/-)apoE(-/-) mice still present a different plaque composition pattern than the arsenic-exposed apoE(-/-) mice.
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Affiliation(s)
- Maryse Lemaire
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2 *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
| | - Catherine A Lemarié
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2 *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
| | - Manuel Flores Molina
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
| | - Cynthia Guilbert
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
| | - Stéphanie Lehoux
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2 *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
| | - Koren K Mann
- *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2 *Department of Oncology, Lady Davis Institute for Medical Research, and Department of Medicine, McGill University, Montréal, Canada H3T 1E2
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33
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Saadane A, Mast N, Charvet CD, Omarova S, Zheng W, Huang SS, Kern TS, Peachey NS, Pikuleva IA. Retinal and nonocular abnormalities in Cyp27a1(-/-)Cyp46a1(-/-) mice with dysfunctional metabolism of cholesterol. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:2403-19. [PMID: 25065682 DOI: 10.1016/j.ajpath.2014.05.024] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 05/21/2014] [Accepted: 05/29/2014] [Indexed: 01/08/2023]
Abstract
Cholesterol elimination from nonhepatic cells involves metabolism to side-chain oxysterols, which serve as transport forms of cholesterol and bioactive molecules modulating a variety of cellular processes. Cholesterol metabolism is tissue specific, and its significance has not yet been established for the retina, where cytochromes P450 (CYP27A1 and CYP46A1) are the major cholesterol-metabolizing enzymes. We generated Cyp27a1(-/-)Cyp46a1(-/-) mice, which were lean and had normal serum cholesterol and glucose levels. These animals, however, had changes in the retinal vasculature, retina, and several nonocular organs (lungs, liver, and spleen). Changes in the retinal vasculature included structural abnormalities (retinal-choroidal anastomoses, arteriovenous shunts, increased permeability, dilation, nonperfusion, and capillary degeneration) and cholesterol deposition and oxidation in the vascular wall, which also exhibited increased adhesion of leukocytes and activation of the complement pathway. Changes in the retina included increased content of cholesterol and its metabolite, cholestanol, which were focally deposited at the apical and basal sides of the retinal pigment epithelium. Retinal macrophages of Cyp27a1(-/-)Cyp46a1(-/-) mice were activated, and oxidative stress was noted in their photoreceptor inner segments. Our findings demonstrate the importance of retinal cholesterol metabolism for maintenance of the normal retina, and suggest new targets for diseases affecting the retinal vasculature.
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Affiliation(s)
- Aicha Saadane
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio
| | - Casey D Charvet
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio
| | - Saida Omarova
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio
| | - Wenchao Zheng
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio
| | - Suber S Huang
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio; Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Timothy S Kern
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Neal S Peachey
- Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio; Cleveland VA Medical Center, Cleveland, Ohio; Department of Medicine, University Hospitals, Cleveland, Ohio
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Cleveland, Ohio.
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Parikh M, Patel K, Soni S, Gandhi T. Liver X Receptor: A Cardinal Target for Atherosclerosis and Beyond. J Atheroscler Thromb 2014. [DOI: 10.5551/jat.19778] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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35
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Lee HR, Jun HK, Choi BK. Tannerella forsythia BspA increases the risk factors for atherosclerosis in ApoE(-/-) mice. Oral Dis 2013; 20:803-8. [PMID: 24372897 DOI: 10.1111/odi.12214] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 11/04/2013] [Accepted: 11/18/2013] [Indexed: 12/23/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the effects of Tannerella forsythia and its major surface virulence factor, BspA, on the progression of atherosclerosis in ApoE(-/-) mice and the expression of lipid metabolism-related genes. METHODS PMA-differentiated THP-1 cells were treated with BspA to detect foam cell formation. The proximal aortas of ApoE(-/-) mice injected with T. forsythia or BspA were stained with oil red O to examine lipid deposition. The serum levels of CRP, HDL, and LDL were detected by ELISA. The liver tissue of T. forsythia- or BspA-injected ApoE(-/-) mice was examined for mRNA expression of lipid metabolism-related genes, such as liver X receptors (LXRα and LXRβ) and ATP-binding cassette transporter A1 (ABCA1). RESULTS Tannerella forsythia and BspA induced foam cell formation in THP-1 cells and accelerated the progression of atherosclerotic lesions in ApoE(-/-) mice. Mouse serum levels of CRP and LDL were increased, and HDL was decreased by T. forsythia and BspA. The expression levels of LXRα and LXRβ, and ABCA1 in liver tissue were decreased by T. forsythia and BspA. CONCLUSIONS Tannerella forsythia and BspA augmented atherosclerotic lesion progression in ApoE(-/-) mice. This process may be associated with downregulation of lipid metabolism-related gene expression.
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Affiliation(s)
- H R Lee
- Division of High-Risk Pathogen Research, Center for Infectious Diseases, National Institute of Health, Cheongwon-gun, Chungbuk, Korea
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36
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Serviddio G, Blonda M, Bellanti F, Villani R, Iuliano L, Vendemiale G. Oxysterols and redox signaling in the pathogenesis of non-alcoholic fatty liver disease. Free Radic Res 2013; 47:881-93. [PMID: 24000796 DOI: 10.3109/10715762.2013.835048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Oxysterols are oxidized species of cholesterol coming from exogenous (e.g. dietary) and endogenous (in vivo) sources. They play critical roles in normal physiologic functions such as regulation of cellular cholesterol homeostasis. Most of biological effects are mediated by interaction with nuclear receptor LXRα, highly expressed in the liver as well as in many other tissues. Such interaction participates in the regulation of whole-body cholesterol metabolism, by acting as "lipid sensors". Moreover, it seems that oxysterols are also suspected to play key roles in several pathologies, including cardiovascular and inflammatory disease, cancer, and neurodegeneration. Growing evidence suggests that oxysterols may contribute to liver injury in non-alcoholic fatty liver disease. The present review focuses on the current status of knowledge on oxysterols' biological role, with an emphasis on LXR signaling and oxysterols' physiopathological relevance in NAFLD, suggesting new pharmacological development that needs to be addressed in the near future.
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Affiliation(s)
- G Serviddio
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia , Italy
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37
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Loren J, Huang Z, Laffitte BA, Molteni V. Liver X receptor modulators: a review of recently patented compounds (2009 - 2012). Expert Opin Ther Pat 2013; 23:1317-35. [PMID: 23826715 DOI: 10.1517/13543776.2013.814640] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION The development of small molecule agonists of the liver X receptors (LXRs) has been an area of interest for over a decade, given the critical role of those receptors in cholesterol metabolism, glucose homeostasis, inflammation, innate immunity and lipogenesis. Many potential indications have been characterized over time including atherosclerosis, diabetes, inflammation, Alzheimer's disease and cancer. However, concerns about the lipogenic effects of full LXRα/β agonists have required extensive efforts aimed at identifying LXRβ agonist with limited activity on the LXRα receptor to increase the safety margins. AREAS COVERED This review includes a summary of the LXR agonists that have reached the clinic and summarizes the patent applications for LXR modulators from September 2009 to December 2012 with emphasis on chemical matters, biological data associated with selected analogs and therapeutic indications. EXPERT OPINION As LXR agonists have the potential to be useful for many indications, the scientific community, despite setbacks due to on-target side effects, has maintained interest and devised strategies to overcome safety hurdles. While a clinical proof of concept still remains elusive, the recent advancement of compounds into the clinic highlights that acceptable safety margins in preclinical species have been achieved.
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Affiliation(s)
- Jon Loren
- Genomics Institute of the Novartis Research Foundation , 10675 John Jay Hopkins Drive, San Diego, CA 92121 , USA +001 858 332 4736 ;
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Suzuki H, Barros RPA, Sugiyama N, Krishnan V, Yaden BC, Kim HJ, Warner M, Gustafsson JÅ. Involvement of estrogen receptor β in maintenance of serotonergic neurons of the dorsal raphe. Mol Psychiatry 2013; 18:674-80. [PMID: 22665260 DOI: 10.1038/mp.2012.62] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The serotonergic neurons of the dorsal raphe (DR) nucleus in the CNS are involved in fear, anxiety and depression. Depression and anxiety occur quite frequently in postmenopausal women, but estrogen replacement to correct these CNS disorders is at present not favored because estrogen carries with it an increased risk for breast cancer. Serotonin synthesis, release and reuptake in the DR are targets of pharmaceuticals in the treatment of depression. In the present study we have examined by immunohistochemistry, the expression of two nuclear receptors, that is, the estrogen receptors ERα and ERβ. We found that ERβ but not ERα is strongly expressed in the DR and there is no sex difference and no change with ageing in the number of tryptophan hydroxylase (TPH)-positive neurons in the DR of wild-type (WT) mice. However, in ovariectomized (OVX) WT and in ERβ(-/-) mice, there was a marked reduction in the number of TPH-positive normal-looking neurons and a marked increase in TPH-positive spindle-shaped cells. These neuronal changes were prevented in mice 1-3 weeks (but not 10 weeks) after OVX by the selective ERβ agonist, LY3201, given as continuous release pellets for 3 days. The ERβ agonist had no effects on glucose homeostasis. Thus, the onset of action of the ERβ agonist is rapid but there is a limited window in time after estrogen loss when the drug is useful. We conclude that, rather than estradiol, ERβ agonists could be useful pharmaceuticals in maintaining functional DR neurons to treat postmenopausal depression.
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Affiliation(s)
- H Suzuki
- Department of Biology and Biochemistry, Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX 77204, USA
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Pannu PS, Allahverdian S, Francis GA. Oxysterol generation and liver X receptor-dependent reverse cholesterol transport: not all roads lead to Rome. Mol Cell Endocrinol 2013; 368:99-107. [PMID: 22884520 DOI: 10.1016/j.mce.2012.07.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 06/30/2012] [Accepted: 07/27/2012] [Indexed: 12/31/2022]
Abstract
Cell cholesterol metabolism is a tightly regulated process, dependent in part on activation of nuclear liver X receptors (LXRs) to increase expression of genes mediating removal of excess cholesterol from cells in the reverse cholesterol transport pathway. LXRs are thought to be activated predominantly by oxysterols generated enzymatically from cholesterol in different cell organelles. Defects resulting in slowed release of cholesterol from late endosomes and lysosomes or reduction in sterol-27-hydroxylase activity lead to specific blocks in oxysterol production and impaired LXR-dependent gene activation. This block does not appear to be compensated by oxysterol production in other cell compartments. The purpose of this review is to summarize current knowledge about oxysterol-dependent activation by LXR of genes involved in reverse cholesterol transport, and what these defects of cell cholesterol homeostasis can teach us about the critical pathways of oxysterol generation for expression of LXR-dependent genes.
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Affiliation(s)
- Parveer S Pannu
- Department of Medicine, UBC James Hogg Research Centre, Institute of Heart and Lung Health at St. Paul's Hospital, Vancouver, BC, Canada V6Z 1Y6.
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40
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Robertson Remen KM, Lerner UH, Gustafsson JÅ, Andersson G. Activation of the liver X receptor-β potently inhibits osteoclastogenesis from lipopolysaccharide-exposed bone marrow-derived macrophages. J Leukoc Biol 2013; 93:71-82. [DOI: 10.1189/jlb.0712339] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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41
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Chigusa Y, Kondoh E, Mogami H, Nishimura F, Ujita M, Kawasaki K, Fujita K, Tatsumi K, Konishi I. ATP-binding cassette transporter A1 expression is decreased in preeclamptic placentas. Reprod Sci 2012; 20:891-8. [PMID: 23275468 DOI: 10.1177/1933719112468956] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Preeclampsia is a pregnancy-specific multisystem disorder characterized by hypertension and proteinuria. Accentuated maternal hyperlipidemia, especially high serum levels of oxidized low-density lipoprotein (oxLDL), is one of the features of preeclampsia. We previously reported that lectin-like oxidized LDL receptor 1 (LOX-1) expression was decreased in preeclamptic placentas. Here, we show that decreased LOX-1 expression is associated with low expression of adenosine triphosphate-binding cassette transporter A1 (ABCA1) in the placenta. The ABCA1 mediates cellular efflux of cholesterol, and liver X receptors (LXRs) are its predominant transcriptional regulators. Both ABCA1 and LXR expressions were significantly lower in preeclamptic placentas than those in normal controls. Oxidized LDL upregulated ABCA1 expression, while LOX-1 blockade resulted in the alleviation of increasing ABCA1 messenger RNA in JAR cells. These results suggest that low LOX-1 expression may lead to insufficient oxLDL uptake, thereby contributing to reduced LXR activation and decreased ABCA1 expression in preeclamptic placentas.
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Affiliation(s)
- Yoshitsugu Chigusa
- Department of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, Japan
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Abstract
Liver X receptors (LXRs) belong to the nuclear receptor superfamily of ligand-dependent transcription factors. LXRs are activated by oxysterols, metabolites of cholesterol, and therefore act as intracellular sensors of this lipid. There are two LXR genes (α and β) that display distinct tissue/cell expression profiles. LXRs interact with regulatory sequences in target genes as heterodimers with retinoid X receptor. Such direct targets of LXR actions include important genes implicated in the control of lipid homeostasis, particularly reverse cholesterol transport. In addition, LXRs attenuate the transcription of genes associated with the inflammatory response indirectly by transrepression. In this review, we describe recent evidence that both highlights the key roles of LXRs in atherosclerosis and inflammation and provides novel insights into the mechanisms underlying their actions. In addition, we discuss the major limitations of LXRs as therapeutic targets for the treatment of atherosclerosis and how these are being addressed.
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Transcriptional integration of metabolism by the nuclear sterol-activated receptors LXR and FXR. Nat Rev Mol Cell Biol 2012; 13:213-24. [PMID: 22414897 DOI: 10.1038/nrm3312] [Citation(s) in RCA: 538] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Nuclear receptors are integrators of hormonal and nutritional signals, mediating changes to metabolic pathways within the body. Given that modulation of lipid and glucose metabolism has been linked to diseases including type 2 diabetes, obesity and atherosclerosis, a greater understanding of pathways that regulate metabolism in physiology and disease is crucial. The liver X receptors (LXRs) and the farnesoid X receptors (FXRs) are activated by oxysterols and bile acids, respectively. Mounting evidence indicates that these nuclear receptors have essential roles, not only in the regulation of cholesterol and bile acid metabolism but also in the integration of sterol, fatty acid and glucose metabolism.
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Oxysterols and their cellular effectors. Biomolecules 2012; 2:76-103. [PMID: 24970128 PMCID: PMC4030866 DOI: 10.3390/biom2010076] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 02/03/2012] [Accepted: 02/07/2012] [Indexed: 11/23/2022] Open
Abstract
Oxysterols are oxidized 27-carbon cholesterol derivatives or by-products of cholesterol biosynthesis, with a spectrum of biologic activities. Several oxysterols have cytotoxic and pro-apoptotic activities, the ability to interfere with the lateral domain organization, and packing of membrane lipids. These properties may account for their suggested roles in the pathology of diseases such as atherosclerosis, age-onset macular degeneration and Alzheimer’s disease. Oxysterols also have the capacity to induce inflammatory responses and play roles in cell differentiation processes. The functions of oxysterols as intermediates in the synthesis of bile acids and steroid hormones, and as readily transportable forms of sterol, are well established. Furthermore, their actions as endogenous regulators of gene expression in lipid metabolism via liver X receptors and the Insig (insulin-induced gene) proteins have been investigated in detail. The cytoplasmic oxysterol-binding protein (OSBP) homologues form a group of oxysterol/cholesterol sensors that has recently attracted a lot of attention. However, their mode of action is, as yet, poorly understood. Retinoic acid receptor-related orphan receptors (ROR) α and γ, and Epstein-Barr virus induced gene 2 (EBI2) have been identified as novel oxysterol receptors, revealing new physiologic oxysterol effector mechanisms in development, metabolism, and immunity, and evoking enhanced interest in these compounds in the field of biomedicine.
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Abstract
Liver X receptors (LXRs) are members of the superfamily of metabolic nuclear receptors, which play central roles in the regulation of cholesterol absorption, efflux, transportation and excretion and many other processes correlating with lipid metabolism. LXRs can also regulate inflammation in vitro and in vivo. Accumulating evidence demonstrates that LXR are involved in the metabolism and inflammation in human diseases. Nonalcoholic fatty liver disease (NAFLD) is classically associated with lipid metabolic disorders and inflammatory responses, especially in the nonalcoholic steatohepatitis (NASH) phase. The effects of LXRs on cholesterol metabolism and inflammation make them attractive as a potential target for the treatment of NAFLD. Since the ability to synthesize triglycerides may be protective in obesity and fatty liver, the hepatic lipogenesis by LXRs should not rule out the possibility of the use of LXRs in NAFLD.
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Affiliation(s)
- Yuan Liu
- Division of Gastroenterology and Hepatology, Shanghai Jiao-Tong University School of Medicine Renji Hospital, Shanghai Institute of Digestive Disease and Key Laboratory of Gastroenterology and Hepatology, Ministry of Health (Shanghai Jiao-Tong University), Shanghai, China
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Stender S, Frikke-Schmidt R, Anestis A, Kardassis D, Sethi AA, Nordestgaard BG, Tybjærg-Hansen A. Genetic Variation in Liver X Receptor Alpha and Risk of Ischemic Vascular Disease in the General Population. Arterioscler Thromb Vasc Biol 2011; 31:2990-6. [DOI: 10.1161/atvbaha.111.223867] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Objective—
Although animal studies indicate that
liver X receptor alpha
(
LXR
α) might influence risk of atherosclerosis, data in humans remain scarce. We tested the hypothesis that genetic variation in
LXR
α associates with risk of ischemic vascular disease and/or plasma lipid and lipoprotein levels in the general population.
Methods and Results—
We studied 10,281 white persons of Danish ancestry from a general population cohort, including 1,986 in whom ischemic heart disease (IHD) developed, and 989 in whom ischemic cerebrovascular disease developed. We examined another 51,429 white persons of Danish ancestry from a general population study, including 3,789 with IHD. We genotyped 10 genetic variants identified by resequencing
LXR
α. Homozygosity for −840AA/−115AA(=2.7%) predicted hazard ratios of 1.3 (95% confidence interval, 1.0–1.7) for IHD, 1.6 (1.2–2.2) for myocardial infarction, and 1.7 (1.3–2.4) for ischemic cerebrovascular disease. The corresponding odds ratios in the second cohort were 1.1 (0.9–1.4) for IHD and 1.5 (1.1–2.0) for myocardial infarction. In the combined studies, odds ratios were 1.2 (1.0–1.4) for IHD and 1.5 (1.2–1.9) for myocardial infarction. Homozygosity for −840AA/−115AA did not associate with lipid or lipoprotein levels.
LXR
α −1830T>C (tagging the haplotype −1830C/−840A/−115A, all r
2
≥0.97) associated with 91% increased transcriptional activity.
Conclusion—
This study suggests that functional genetic variation in
LXR
α predicts risk of ischemic vascular disease in the general population.
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Affiliation(s)
- Stefan Stender
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Ruth Frikke-Schmidt
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Aristomenis Anestis
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Dimitris Kardassis
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Amar A. Sethi
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Børge G. Nordestgaard
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
| | - Anne Tybjærg-Hansen
- From the Department of Clinical Biochemistry (S.S., R.F.-S., A.A.S., A.T.-H.), Rigshospitalet, Copenhagen University Hospital and Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Biochemistry (A.A., D.K.), University of Crete Medical School, Heraklion, Greece; Pacific Biometrics, Inc (A.A.S.), Seattle, WA; Department of Clinical Biochemistry (A.A.S., B.G.N.) and The Copenhagen General Population Study (R.F.-S., B.G.N., A.T.-H.), Herlev Hospital, and The Copenhagen City
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Marwarha G, Rhen T, Schommer T, Ghribi O. The oxysterol 27-hydroxycholesterol regulates α-synuclein and tyrosine hydroxylase expression levels in human neuroblastoma cells through modulation of liver X receptors and estrogen receptors--relevance to Parkinson's disease. J Neurochem 2011; 119:1119-36. [PMID: 21951066 DOI: 10.1111/j.1471-4159.2011.07497.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Loss of dopaminergic neurons and α-synuclein accumulation are the two major pathological hallmarks of Parkinson's disease. Currently, the mechanisms governing depletion of dopamine content and α-synuclein accumulation are not well understood. We showed that the oxysterol 27-hydroxycholesterol (27-OHC) reduces the expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis, and increases α-synuclein levels in SH-SY5Y cells. However, the cellular mechanisms involved in 27-OHC effects were not elucidated. In this study, we demonstrate that 27-OHC regulates TH and α-synuclein expression levels through the estrogen receptors (ER) and liver X receptors (LXR). We specifically show that inhibition of ERβ mediates 27-OHC-induced decrease in TH expression, an effect reversed by the ER agonist estradiol. We also show that 27-OHC and the LXR agonist GW3965 increase α-synuclein while the LXR antagonist 5α-6α-epoxycholesterol-3-sulfate significantly attenuated the 27-OHC-induced increase in α-synuclein expression. We further demonstrate that LXRβ positively regulates α-synuclein expression and 27-OHC increases LXRβ-mediated α-synuclein transcription. Our results demonstrate the involvement of two distinct pathways that are involved in the 27-OHC regulation of TH and α-synuclein levels. Concomitant activation of ERβ and inhibition of LXRβ prevent 27-OHC effects and may therefore reduce the progression of Parkinson's disease by precluding TH reduction and α-synuclein accumulation.
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Affiliation(s)
- Gurdeep Marwarha
- Department of Pharmacology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, USA
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Remen KMR, Henning P, Lerner UH, Gustafsson JÅ, Andersson G. Activation of liver X receptor (LXR) inhibits receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation in an LXRβ-dependent mechanism. J Biol Chem 2011; 286:33084-94. [PMID: 21784849 DOI: 10.1074/jbc.m111.235937] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Bone destruction is the major pathological process in many bone metabolic diseases and is a result of increased osteoclast formation and bone resorption. The liver X receptors (α,β), important regulators of cholesterol metabolism and inflammatory signaling, have recently been observed to play a role in both physiological and pathological bone turnover. However, the relationship between liver X receptors (LXR) and osteoclast differentiation/formation remains unknown. Here, we report that the LXR ligand GW3965 is able to clearly and potently inhibit the formation of mature osteoclasts from receptor activator of nuclear factor κB ligand (RANKL)-stimulated human and murine osteoclast precursors. This results in a significant inhibition of bone resorption. We observed that GW3965 significantly inhibited expression of the osteoclast markers tartrate-resistant acid phosphatase, cathepsin K, osteoclast-associated receptor (OSCAR), and calcitonin receptor, appearing to act in an NFATc1/p38/microphthalmia-associated transcription factor (MITF)-dependent mechanism, independently of receptor activator of nuclear factor κB or c-Fos and not directly involving the NFκB pathways. GW3965 was less effective in RAW264.7 monocyte/macrophage cells, which are more committed into the osteoclast lineage. Also, GW3965 seemed to act differently depending on the source of the progenitor cells as it had no effect on calvarial osteoclasts, compared with marrow or blood-derived monocytes. As these effects were abolished in osteoclast precursors derived from LXRβ(-/-) mice, we suggest that GW3965 acts via an LXRβ-dependent mechanism. Taken together, our results suggest that the LXR can act as an important inhibitor of RANKL-mediated osteoclast differentiation.
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Patel MB, Oza NA, Anand IS, Deshpande SS, Patel CN. Liver x receptor: a novel therapeutic target. Indian J Pharm Sci 2011; 70:135-44. [PMID: 20046702 PMCID: PMC2792482 DOI: 10.4103/0250-474x.41445] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2007] [Revised: 02/14/2008] [Accepted: 02/20/2008] [Indexed: 01/04/2023] Open
Abstract
The liver X receptors α and β are orphan nuclear receptors that are key regulators in maintaining cholesterol homeostasis. Originally they were found to play an important role in reverse cholesterol transport, a pathway for the removal of excess cellular cholesterol. However several groups have now shown that the liver X receptors also functions in lipid and carbohydrate metabolism, cellular differentiation, apoptosis and many immune responses. Tissue distribution of the two paralogues differs with liver X receptor β ubiquitously expressed, while liver X receptor α is confined to the liver, kidney, intestine, spleen, adipose tissue, macrophages and skeletal muscle. The endogenous ligands for the liver X receptors are certain oxidized derivatives of cholesterol, the oxysterols. Upon activation by oxysterols, the receptors form obligate heterodimers with retinoid X receptors α, β and γ; and become competent to activate the transcription of target genes.
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Affiliation(s)
- M B Patel
- Department of Pharmacology, Shri Sarvajanik Pharmacy College, Near Arvind Baug, Mehsana - 384 001, India
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Korach-André M, Archer A, Gabbi C, Barros RP, Pedrelli M, Steffensen KR, Pettersson AT, Laurencikiene J, Parini P, Gustafsson JÅ. Liver X receptors regulate de novo lipogenesis in a tissue-specific manner in C57BL/6 female mice. Am J Physiol Endocrinol Metab 2011; 301:E210-22. [PMID: 21521718 DOI: 10.1152/ajpendo.00541.2010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The liver X receptors (LXRs) play a key role in cholesterol and bile acid metabolism but are also important regulators of glucose metabolism. Recently, LXRs have been proposed as a glucose sensor affecting LXR-dependent gene expression. We challenged wild-type (WT) and LXRαβ(-/-) mice with a normal diet (ND) or a high-carbohydrate diet (HCD). Magnetic resonance imaging showed different fat distribution between WT and LXRαβ(-/-) mice. Surprisingly, gonadal (GL) adipocyte volume decreased on HCD compared with ND in WT mice, whereas it slightly increased in LXRαβ(-/-) mice. Interestingly, insulin-stimulated lipogenesis of isolated GL fat cells was reduced on HCD compared with ND in LXRαβ(-/-) mice, whereas no changes were observed in WT mice. Net de novo lipogenesis (DNL) calculated from Vo(2) and Vco(2) was significantly higher in LXRαβ(-/-) than in WT mice on HCD. Histology of HCD-fed livers showed hepatic steatosis in WT mice but not in LXRαβ(-/-) mice. Glucose tolerance was not different between groups, but insulin sensitivity was decreased by the HCD in WT but not in LXRαβ(-/-) mice. Finally, gene expression analysis of adipose tissue showed induced expression of genes involved in DNL in LXRαβ(-/-) mice compared with WT animals as opposed to the liver, where expression of DNL genes was repressed in LXRαβ(-/-) mice. We thus conclude that absence of LXRs stimulates DNL in adipose tissue, but suppresses DNL in the liver, demonstrating opposite roles of LXR in DNL regulation in these two tissues. These results show tissue-specific regulation of LXR activity, a crucial finding for drug development.
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Affiliation(s)
- Marion Korach-André
- Department of Biosciences and Nutrition and Center for Biosciences at NOVUM, Karolinska Institutet, Lipid Laboratory, Huddinge, Sweden.
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