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Reinisch I, Michenthaler H, Sulaj A, Moyschewitz E, Krstic J, Galhuber M, Xu R, Riahi Z, Wang T, Vujic N, Amor M, Zenezini Chiozzi R, Wabitsch M, Kolb D, Georgiadi A, Glawitsch L, Heitzer E, Schulz TJ, Schupp M, Sun W, Dong H, Ghosh A, Hoffmann A, Kratky D, Hinte LC, von Meyenn F, Heck AJR, Blüher M, Herzig S, Wolfrum C, Prokesch A. Adipocyte p53 coordinates the response to intermittent fasting by regulating adipose tissue immune cell landscape. Nat Commun 2024; 15:1391. [PMID: 38360943 PMCID: PMC10869344 DOI: 10.1038/s41467-024-45724-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 02/02/2024] [Indexed: 02/17/2024] Open
Abstract
In obesity, sustained adipose tissue (AT) inflammation constitutes a cellular memory that limits the effectiveness of weight loss interventions. Yet, the impact of fasting regimens on the regulation of AT immune infiltration is still elusive. Here we show that intermittent fasting (IF) exacerbates the lipid-associated macrophage (LAM) inflammatory phenotype of visceral AT in obese mice. Importantly, this increase in LAM abundance is strongly p53 dependent and partly mediated by p53-driven adipocyte apoptosis. Adipocyte-specific deletion of p53 prevents LAM accumulation during IF, increases the catabolic state of adipocytes, and enhances systemic metabolic flexibility and insulin sensitivity. Finally, in cohorts of obese/diabetic patients, we describe a p53 polymorphism that links to efficacy of a fasting-mimicking diet and that the expression of p53 and TREM2 in AT negatively correlates with maintaining weight loss after bariatric surgery. Overall, our results demonstrate that p53 signalling in adipocytes dictates LAM accumulation in AT under IF and modulates fasting effectiveness in mice and humans.
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Affiliation(s)
- Isabel Reinisch
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
- Institute of Food Nutrition and Health, Department of Health Sciences and Technology, Eidgenössische Technische Hochschule Zürich (ETH), Schwerzenbach, Switzerland
| | - Helene Michenthaler
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Alba Sulaj
- Institute for Diabetes and Cancer, Helmholtz Munich, German Center for Diabetes Research (DZD), Neuherberg, Germany
- Department of Endocrinology, Diabetology, Metabolism and Clinical Chemistry (Internal Medicine 1), Heidelberg University Hospital, Heidelberg, Germany
| | - Elisabeth Moyschewitz
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Jelena Krstic
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Markus Galhuber
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Ruonan Xu
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Zina Riahi
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Tongtong Wang
- Institute of Food Nutrition and Health, Department of Health Sciences and Technology, Eidgenössische Technische Hochschule Zürich (ETH), Schwerzenbach, Switzerland
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Melina Amor
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Riccardo Zenezini Chiozzi
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Dagmar Kolb
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
- Core Facility Ultrastructure Analysis, Medical University of Graz, Graz, Austria
| | - Anastasia Georgiadi
- Institute for Diabetes and Cancer, Helmholtz Munich, German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Lisa Glawitsch
- Institute of Human Genetics, Diagnostic and Research Center for Molecular BioMedicine, Medical University of Graz, Graz, Austria
| | - Ellen Heitzer
- Institute of Human Genetics, Diagnostic and Research Center for Molecular BioMedicine, Medical University of Graz, Graz, Austria
| | - Tim J Schulz
- Department of Adipocyte Development and Nutrition, German Institute of Human Nutrition, Nuthetal, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- University of Potsdam, Institute of Nutritional Science, Nuthetal, Germany
| | - Michael Schupp
- Institute of Pharmacology, Max Rubner Center (MRC) for Cardiovascular Metabolic Renal Research, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Wenfei Sun
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Hua Dong
- Stem Cell Biology and Regenerative Medicine Institute, University of Stanford, Stanford, CA, USA
| | - Adhideb Ghosh
- Institute of Food Nutrition and Health, Department of Health Sciences and Technology, Eidgenössische Technische Hochschule Zürich (ETH), Schwerzenbach, Switzerland
- Functional Genomics Center Zurich, Eidgenössische Technische Hochschule Zürich (ETH), Zurich, Switzerland
| | - Anne Hoffmann
- Helmholtz Institute for Metabolic Obesity and Vascular Research (HI-MAG) of the Helmholtz Center Munich at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Laura C Hinte
- Laboratory of Nutrition and Metabolic Epigenetics, Institute for Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Ferdinand von Meyenn
- Laboratory of Nutrition and Metabolic Epigenetics, Institute for Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Matthias Blüher
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Stephan Herzig
- Institute for Diabetes and Cancer, Helmholtz Munich, German Center for Diabetes Research (DZD), Neuherberg, Germany
- Department of Endocrinology, Diabetology, Metabolism and Clinical Chemistry (Internal Medicine 1), Heidelberg University Hospital, Heidelberg, Germany
| | - Christian Wolfrum
- Institute of Food Nutrition and Health, Department of Health Sciences and Technology, Eidgenössische Technische Hochschule Zürich (ETH), Schwerzenbach, Switzerland
| | - Andreas Prokesch
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria.
- BioTechMed-Graz, Graz, Austria.
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Bianco V, Korbelius M, Vujic N, Akhmetshina A, Amor M, Kolb D, Pirchheim A, Bradic I, Kuentzel KB, Buerger M, Schauer S, Phan HTT, Bulfon D, Hoefler G, Zimmermann R, Kratky D. Impact of (intestinal) LAL deficiency on lipid metabolism and macrophage infiltration. Mol Metab 2023; 73:101737. [PMID: 37182562 PMCID: PMC10209539 DOI: 10.1016/j.molmet.2023.101737] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 03/01/2023] [Accepted: 05/08/2023] [Indexed: 05/16/2023] Open
Abstract
OBJECTIVE To date, the only enzyme known to be responsible for the hydrolysis of cholesteryl esters and triacylglycerols in the lysosome at acidic pH is lysosomal acid lipase (LAL). Lipid malabsorption in the small intestine (SI), accompanied by macrophage infiltration, is one of the most common pathological features of LAL deficiency. However, the exact role of LAL in intestinal lipid metabolism is still unknown. METHODS We collected three parts of the SI (duodenum, jejunum, ileum) from mice with a global (LAL KO) or intestine-specific deletion of LAL (iLAL KO) and corresponding controls. RESULTS We observed infiltration of lipid-associated macrophages into the lamina propria, where neutral lipids accumulate massively in the SI of LAL KO mice. In addition, LAL KO mice absorb less dietary lipids but have accelerated basolateral lipid uptake, secrete fewer chylomicrons, and have increased fecal lipid loss. Inflammatory markers and genes involved in lipid metabolism were overexpressed in the duodenum of old but not in younger LAL KO mice. Despite the significant reduction of LAL activity in enterocytes of enterocyte-specific (iLAL) KO mice, villous morphology, intestinal lipid concentrations, expression of lipid transporters and inflammatory genes, as well as lipoprotein secretion were comparable to control mice. CONCLUSIONS We conclude that loss of LAL only in enterocytes is insufficient to cause lipid deposition in the SI, suggesting that infiltrating macrophages are the key players in this process.
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Affiliation(s)
- Valentina Bianco
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Melanie Korbelius
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Alena Akhmetshina
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Melina Amor
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Dagmar Kolb
- Core Facility Ultrastructure Analysis, Center for Medical Research, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Anita Pirchheim
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Ivan Bradic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Katharina B Kuentzel
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Martin Buerger
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Silvia Schauer
- Diagnostics and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Huyen T T Phan
- Diagnostics and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Dominik Bulfon
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Gerald Hoefler
- Diagnostics and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Robert Zimmermann
- BioTechMed-Graz, Graz, Austria; Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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Liebscher G, Vujic N, Schreiber R, Heine M, Krebiehl C, Duta-Mare M, Lamberti G, de Smet CH, Hess MW, Eichmann TO, Hölzl S, Scheja L, Heeren J, Kratky D, Huber LA. The lysosomal LAMTOR / Ragulator complex is essential for nutrient homeostasis in brown adipose tissue. Mol Metab 2023; 71:101705. [PMID: 36907508 PMCID: PMC10074977 DOI: 10.1016/j.molmet.2023.101705] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 02/28/2023] [Accepted: 03/06/2023] [Indexed: 03/13/2023] Open
Abstract
OBJECTIVE In brown adipose tissue (iBAT), the balance between lipid/glucose uptake and lipolysis is tightly regulated by insulin signaling. Downstream of the insulin receptor, PDK1 and mTORC2 phosphorylate AKT, which activates glucose uptake and lysosomal mTORC1 signaling. The latter requires the late endosomal/lysosomal adaptor and MAPK and mTOR activator (LAMTOR/Ragulator) complex, which serves to translate the nutrient status of the cell to the respective kinase. However, the role of LAMTOR in metabolically active iBAT has been elusive. METHODS Using an AdipoqCRE-transgenic mouse line, we deleted LAMTOR2 (and thereby the entire LAMTOR complex) in adipose tissue (LT2 AKO). To examine the metabolic consequences, we performed metabolic and biochemical studies in iBAT isolated from mice housed at different temperatures (30 °C, room temperature and 5 °C), after insulin treatment, or in fasted and refed condition. For mechanistic studies, mouse embryonic fibroblasts (MEFs) lacking LAMTOR 2 were analyzed. RESULTS Deletion of the LAMTOR complex in mouse adipocytes resulted in insulin-independent AKT hyperphosphorylation in iBAT, causing increased glucose and fatty acid uptake, which led to massively enlarged lipid droplets. As LAMTOR2 was essential for the upregulation of de novo lipogenesis, LAMTOR2 deficiency triggered exogenous glucose storage as glycogen in iBAT. These effects are cell autonomous, since AKT hyperphosphorylation was abrogated by PI3K inhibition or by deletion of the mTORC2 component Rictor in LAMTOR2-deficient MEFs. CONCLUSIONS We identified a homeostatic circuit for the maintenance of iBAT metabolism that links the LAMTOR-mTORC1 pathway to PI3K-mTORC2-AKT signaling downstream of the insulin receptor.
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Affiliation(s)
- Gudrun Liebscher
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Nemanja Vujic
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstr. 6, 8010 Graz, Austria
| | - Renate Schreiber
- Institute of Molecular Biosciences, University of Graz, Heinrichstrasse 31, 8010 Graz, Austria
| | - Markus Heine
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Caroline Krebiehl
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Madalina Duta-Mare
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstr. 6, 8010 Graz, Austria
| | - Giorgia Lamberti
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Cedric H de Smet
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Michael W Hess
- Institute of Histology and Embryology, Medical University of Innsbruck, Müllerstrasse 59, 6020 Innsbruck, Austria
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Heinrichstrasse 31, 8010 Graz, Austria
| | - Sarah Hölzl
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Ludger Scheja
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Dagmar Kratky
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstr. 6, 8010 Graz, Austria; BioTechMed-Graz, Mozartgasse 12, 8010 Graz, Austria
| | - Lukas A Huber
- Division of Cell Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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4
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Joshi L, Plastira I, Bernhart E, Reicher H, Koshenov Z, Graier WF, Vujic N, Kratky D, Rivera R, Chun J, Sattler W. Lysophosphatidic Acid Receptor 5 (LPA 5) Knockout Ameliorates the Neuroinflammatory Response In Vivo and Modifies the Inflammatory and Metabolic Landscape of Primary Microglia In Vitro. Cells 2022; 11:cells11071071. [PMID: 35406635 PMCID: PMC8998093 DOI: 10.3390/cells11071071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/14/2022] [Accepted: 03/20/2022] [Indexed: 12/02/2022] Open
Abstract
Systemic inflammation induces alterations in the finely tuned micromilieu of the brain that is continuously monitored by microglia. In the CNS, these changes include increased synthesis of the bioactive lipid lysophosphatidic acid (LPA), a ligand for the six members of the LPA receptor family (LPA1-6). In mouse and human microglia, LPA5 belongs to a set of receptors that cooperatively detect danger signals in the brain. Engagement of LPA5 by LPA polarizes microglia toward a pro-inflammatory phenotype. Therefore, we studied the consequences of global LPA5 knockout (-/-) on neuroinflammatory parameters in a mouse endotoxemia model and in primary microglia exposed to LPA in vitro. A single endotoxin injection (5 mg/kg body weight) resulted in lower circulating concentrations of TNFα and IL-1β and significantly reduced gene expression of IL-6 and CXCL2 in the brain of LPS-injected LPA5-/- mice. LPA5 deficiency improved sickness behavior and energy deficits produced by low-dose (1.4 mg LPS/kg body weight) chronic LPS treatment. LPA5-/- microglia secreted lower concentrations of pro-inflammatory cyto-/chemokines in response to LPA and showed higher maximal mitochondrial respiration under basal and LPA-activated conditions, further accompanied by lower lactate release, decreased NADPH and GSH synthesis, and inhibited NO production. Collectively, our data suggest that LPA5 promotes neuroinflammation by transmiting pro-inflammatory signals during endotoxemia through microglial activation induced by LPA.
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Affiliation(s)
- Lisha Joshi
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Ioanna Plastira
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Eva Bernhart
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Helga Reicher
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Zhanat Koshenov
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Wolfgang F. Graier
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
- BioTechMed-Graz, 8010 Graz, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
- BioTechMed-Graz, 8010 Graz, Austria
| | - Richard Rivera
- Translational Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA; (R.R.); (J.C.)
| | - Jerold Chun
- Translational Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA; (R.R.); (J.C.)
| | - Wolfgang Sattler
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; (L.J.); (I.P.); (E.B.); (H.R.); (Z.K.); (W.F.G.); (N.V.); (D.K.)
- BioTechMed-Graz, 8010 Graz, Austria
- Correspondence: ; Tel.: +43-316-385-71950
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5
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Helderman RC, Whitney DG, Duta-Mare M, Akhmetshina A, Vujic N, Jayapalan S, Nyman JS, Misra BB, Rosen CJ, Czech MP, Kratky D, Rendina-Ruedy E. Loss of function of lysosomal acid lipase (LAL) profoundly impacts osteoblastogenesis and increases fracture risk in humans. Bone 2021; 148:115946. [PMID: 33838322 PMCID: PMC8108562 DOI: 10.1016/j.bone.2021.115946] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 03/26/2021] [Accepted: 04/01/2021] [Indexed: 11/28/2022]
Abstract
Lysosomal acid lipase (LAL) is essential for cholesteryl ester (CE) and triacylglycerol (TAG) hydrolysis in the lysosome. Clinically, an autosomal recessive LIPA mutation causes LAL deficiency (LALD), previously described as Wolman Disease or Cholesteryl Ester Storage Disease (CESD). LAL-D is associated with ectopic lipid accumulation in the liver, small intestine, spleen, adrenal glands, and blood. Considering the importance of unesterified cholesterol and fatty acids in bone metabolism, we hypothesized that LAL is essential for bone formation, and ultimately, skeletal health. To investigate the role of LAL in skeletal homeostasis, we used LAL-deficient (-/-) mice, in vitro osteoblast cultures, and novel clinical data from LAL-D patients. Both male and female LAL-/- mice demonstarted lower trabecular and cortical bone parameters , which translated to reduced biomechanical properties. Further histological analyses revealed that LAL-/- mice had fewer osteoblasts, with no change in osteoclast or marrow adipocyte numbers. In studying the cell-autonomous role of LAL, we observed impaired differentiation of LAL-/- calvarial osteoblasts and in bone marrow stromal cells treated with the LAL inhibitor lalistat. Consistent with LAL's role in other tissues, lalistat resulted in profound lipid puncta accumulation and an altered intracellular lipid profile. Finally, we analyzed a large de-identified national insurance database (i.e. 2016/2017 Optum Clinformatics®) which revealed that adults (≥18 years) with CESD (n = 3076) had a higher odds ratio (OR = 1.21; 95% CI = 1.03-1.41) of all-cause fracture at any location compared to adults without CESD (n = 13.7 M) after adjusting for demographic variables and osteoporosis. These data demonstrate that alterations in LAL have significant clinical implications related to fracture risk and that LAL's modulation of lipid metabolism is a critical for osteoblast function.
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Affiliation(s)
- Ron C Helderman
- Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA; Center for Bone Biology, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Daniel G Whitney
- Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, MI 48108, USA; Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, MI, 48107, USA
| | - Madalina Duta-Mare
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - Alena Akhmetshina
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - Shobana Jayapalan
- Center for Bone Biology, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jeffry S Nyman
- Center for Bone Biology, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37212, USA
| | - Biswapriya B Misra
- Center for Precision Medicine, Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27104, USA
| | - Clifford J Rosen
- Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria
| | - Elizabeth Rendina-Ruedy
- Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA; Center for Bone Biology, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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6
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Schittmayer M, Vujic N, Darnhofer B, Korbelius M, Honeder S, Kratky D, Birner-Gruenberger R. Spatially Resolved Activity-based Proteomic Profiles of the Murine Small Intestinal Lipases. Mol Cell Proteomics 2020; 19:2104-2115. [PMID: 33023980 PMCID: PMC7710144 DOI: 10.1074/mcp.ra120.002171] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/28/2020] [Indexed: 01/05/2023] Open
Abstract
Despite the crucial function of the small intestine in nutrient uptake our understanding of the molecular events underlying the digestive function is still rudimentary. Recent studies demonstrated that enterocytes do not direct the entire dietary triacylglycerol toward immediate chylomicron synthesis. Especially after high-fat challenges, parts of the resynthesized triacylglycerol are packaged into cytosolic lipid droplets for transient storage in the endothelial layer of the small intestine. The reason for this temporary storage of triacylglycerol is not completely understood. To utilize lipids from cytosolic lipid droplets for chylomicron synthesis in the endoplasmic reticulum, stored triacylglycerol has to be hydrolyzed either by cytosolic lipolysis or lipophagy. Interestingly, triacylglycerol storage and chylomicron secretion rates are unevenly distributed along the small intestine, with the proximal jejunum exhibiting the highest intermittent storage capacity. We hypothesize that correlating hydrolytic enzyme activities with the reported distribution of triacylglycerol storage and chylomicron secretion in different sections of the small intestine is a promising strategy to determine key enzymes in triacylglycerol remobilization. We employed a serine hydrolase specific activity-based labeling approach in combination with quantitative proteomics to identify and rank hydrolases based on their relative activity in 11 sections of the small intestine. Moreover, we identified several clusters of enzymes showing similar activity distribution along the small intestine. Merging our activity-based results with substrate specificity and subcellular localization known from previous studies, carboxylesterase 2e and arylacetamide deacetylase emerge as promising candidates for triacylglycerol mobilization from cytosolic lipid droplets in enterocytes.
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Affiliation(s)
- Matthias Schittmayer
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Vienna, Austria; Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Barbara Darnhofer
- Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Melanie Korbelius
- Gottfried Schatz Research Center, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Sophie Honeder
- Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
| | - Ruth Birner-Gruenberger
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Vienna, Austria; Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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7
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Korbelius M, Vujic N, Sachdev V, Obrowsky S, Rainer S, Gottschalk B, Graier WF, Kratky D. ATGL/CGI-58-Dependent Hydrolysis of a Lipid Storage Pool in Murine Enterocytes. Cell Rep 2020; 28:1923-1934.e4. [PMID: 31412256 PMCID: PMC6713565 DOI: 10.1016/j.celrep.2019.07.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 03/29/2019] [Accepted: 07/11/2019] [Indexed: 12/22/2022] Open
Abstract
As circulating lipid levels are balanced by the rate of lipoprotein release and clearance from the plasma, lipid absorption in the small intestine critically contributes to the maintenance of whole-body lipid homeostasis. Within enterocytes, excessive triglycerides are transiently stored as cytosolic lipid droplets (cLDs), and their mobilization sustains lipid supply during interprandial periods. Using mice lacking adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) exclusively in the intestine (intestine-specific double KO [iDKO]), we show that ATGL/CGI-58 are not involved in providing substrates for chylomicron synthesis. Massive intestinal cLD accumulation in iDKO mice independent of dietary lipids together with inefficient lipid incorporation into cLDs in the early absorption phase demonstrate the existence of a secretion/re-uptake cycle, corroborating the availability of two diverse cLD pools. This study identified ATGL/CGI-58 as critical players in the catabolism of basolaterally (blood) derived lipids and highlights the necessity to modify the current model of intestinal lipid metabolism.
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Affiliation(s)
- Melanie Korbelius
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Vinay Sachdev
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Sascha Obrowsky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Silvia Rainer
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Benjamin Gottschalk
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria; BioTechMed-Graz, 8010 Graz, Styria, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Styria, Austria; BioTechMed-Graz, 8010 Graz, Styria, Austria.
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8
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Bischof H, Burgstaller S, Vujic N, Madl T, Kratky D, Graier WF, Malli R. Purification and Application of Genetically Encoded Potassium Ion Indicators for Quantification of Potassium Ion Concentrations within Biological Samples. Curr Protoc Chem Biol 2019; 11:e71. [PMID: 31483097 PMCID: PMC6927797 DOI: 10.1002/cpch.71] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Vital cells maintain a steep potassium ion (K+ ) gradient across the plasma membrane. Intracellular potassium ion concentrations ([K+ ]) and especially the [K+ ] within the extracellular matrix are strictly regulated, the latter within a narrow range of ∼3.5 to 5.0 mM. Alterations of the extracellular K+ homeostasis are associated with severe pathological alterations and systemic diseases including hypo- or hypertension, heart rate alterations, heart failure, neuronal damage or abnormal skeleton muscle function. In higher eukaryotic organisms, the maintenance of the extracellular [K+ ] is mainly achieved by the kidney, responsible for K+ excretion and reabsorption. Thus, renal dysfunctions are typically associated with alterations in serum- or plasma [K+ ]. Generally, [K+ ] quantifications within bodily fluids are performed using ion selective electrodes. However, tracking such alterations in experimental models such as mice features several difficulties, mainly due to the small blood volume of these animals, hampering the repetitive collection of sample volumes required for measurements using ion selective electrodes. We have recently developed highly sensitive, genetically encoded potassium ion indicators, the GEPIIs, applicable for in vitro determinations of [K+ ]. In addition to the determination of [K+ ] within bodily fluids, GEPIIs proved suitable for the real-time visualization of cell viability over time and the exact determination of the number of dead cells. © 2019 The Authors.
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Affiliation(s)
- H Bischof
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - S Burgstaller
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - N Vujic
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - T Madl
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - D Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - W F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - R Malli
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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9
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Vujic N, Korbelius M, Rainer S, Sachdev V, Radovic B, Kratky D. Effects Of Intestinal Dgat1 Deficiency On Atherosclerosis In Apoe-Knockout Mice. Atherosclerosis 2019. [DOI: 10.1016/j.atherosclerosis.2019.06.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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Goeritzer M, Schlager S, Vujic N, Kolb D, Schuligoi R, Heinemann A, Radovic B, Kratky D. Loss Of Adipose Triglyceride Lipase Affects Platelet Function. Atherosclerosis 2019. [DOI: 10.1016/j.atherosclerosis.2019.06.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Ivanov S, Viaud M, Vujic N, Duta-Mare M, Dugail I, Hainault I, Stehlik C, Marchetti S, Boyer L, Guinamard R, Foufelle F, Bochem A, Hovingh K, Thorp E, Gautier E, Kratky D, Yvan-Charvet L. Lysosomal Cholesterol Hydrolysis Couples Efferocytosis To Anti-Inflammatory Oxysterol Production. Atherosclerosis 2019. [DOI: 10.1016/j.atherosclerosis.2019.06.223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Vujic N, Korbelius M, Leopold C, Duta-Mare M, Rainer S, Schlager S, Goeritzer M, Kolb D, Eichmann TO, Diwoky C, Zimmer A, Zimmermann R, Lass A, Radovic B, Kratky D. Monoglyceride lipase deficiency affects hepatic cholesterol metabolism and lipid-dependent gut transit in ApoE-/- mice. Oncotarget 2018; 8:33122-33136. [PMID: 28380440 PMCID: PMC5464855 DOI: 10.18632/oncotarget.16529] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 03/14/2017] [Indexed: 11/25/2022] Open
Abstract
Monoglyceride lipase (MGL) hydrolyzes monoglycerides (MGs) to glycerol and fatty acids. Among various MG species MGL also degrades 2-arachidonoylglycerol (2-AG), the most abundant endocannabinoid and potent activator of cannabinoid receptors (CBR) 1 and 2. MGL-knockout (-/-) mice exhibit pronounced 2-AG accumulation, but lack central cannabimimetic effects due to CB1R desensitization. We have previously shown that MGL affects plaque stability in apolipoprotein E (ApoE)-/- mice, an established animal model for dyslipidemia and atherosclerosis. In the current study, we investigated functional consequences of MGL deficiency on lipid and energy metabolism in ApoE/MGL double knockout (DKO) mice. MGL deficiency affected hepatic cholesterol metabolism by causing increased cholesterol elimination via the biliary pathway. Moreover, DKO mice exhibit lipid-triggered delay in gastric emptying without major effects on overall triglyceride and cholesterol absorption. The observed phenotype of DKO mice is likely not a consequence of potentiated CB1R signaling but rather dependent on the activation of alternative signaling pathways. We conclude that MGL deficiency causes complex metabolic changes including cholesterol metabolism and regulation of gut transit independent of the endocannabinoid system.
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Affiliation(s)
- Nemanja Vujic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Melanie Korbelius
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Christina Leopold
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Madalina Duta-Mare
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Silvia Rainer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Stefanie Schlager
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Madeleine Goeritzer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Dagmar Kolb
- Center for Medical Research, Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Austria
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Clemens Diwoky
- Institute of Biomedical Engineering, Graz University of Technology, Graz, Austria.,Current address: Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Andreas Zimmer
- Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Robert Zimmermann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Branislav Radovic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
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13
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Viaud M, Ivanov S, Vujic N, Duta-Mare M, Aira LE, Barouillet T, Garcia E, Orange F, Dugail I, Hainault I, Stehlik C, Marchetti S, Boyer L, Guinamard R, Foufelle F, Bochem A, Hovingh KG, Thorp EB, Gautier EL, Kratky D, Dasilva-Jardine P, Yvan-Charvet L. Lysosomal Cholesterol Hydrolysis Couples Efferocytosis to Anti-Inflammatory Oxysterol Production. Circ Res 2018. [PMID: 29523554 DOI: 10.1161/circresaha.117.312333] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Macrophages face a substantial amount of cholesterol after the ingestion of apoptotic cells, and the LIPA (lysosomal acid lipase) has a major role in hydrolyzing cholesteryl esters in the endocytic compartment. OBJECTIVE Here, we directly investigated the role of LIPA-mediated clearance of apoptotic cells both in vitro and in vivo. METHODS AND RESULTS We show that LIPA inhibition causes a defective efferocytic response because of impaired generation of 25-hydroxycholesterol and 27-hydroxycholesterol. Reduced synthesis of 25-hydroxycholesterol after LIPA inhibition contributed to defective mitochondria-associated membrane leading to mitochondrial oxidative stress-induced NLRP3 (NOD-like receptor family, pyrin domain containing) inflammasome activation and caspase-1-dependent Rac1 (Ras-related C3 botulinum toxin substrate 1) degradation. A secondary event consisting of failure to appropriately activate liver X receptor-mediated pathways led to mitigation of cholesterol efflux and apoptotic cell clearance. In mice, LIPA inhibition caused defective clearance of apoptotic lymphocytes and stressed erythrocytes by hepatic and splenic macrophages, culminating in splenomegaly and splenic iron accumulation under hypercholesterolemia. CONCLUSIONS Our findings position lysosomal cholesterol hydrolysis as a critical process that prevents metabolic inflammation by enabling efficient macrophage apoptotic cell clearance.
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Affiliation(s)
- Manon Viaud
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Stoyan Ivanov
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Nemanja Vujic
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Austria (N.V., M.D.-M., D.K.)
| | - Madalina Duta-Mare
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Austria (N.V., M.D.-M., D.K.)
| | - Lazaro-Emilio Aira
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | | | - Elsa Garcia
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Francois Orange
- UFR Sciences, Faculté des Sciences de l'Université de Nice-Sophia Antipolis, France (F.O.)
| | - Isabelle Dugail
- Institut National de la Santé et de la Recherche Médicale (INSERM) UMR_S 1166, Pierre & Marie Curie University, ICAN Institute of Cardiometabolism & Nutrition, Hôpital de la Pitié, Boulevard de l'Hôpital, Paris, France (I.D., E.L.G.)
| | - Isabelle Hainault
- Institut National de la Santé et de la Recherche Médicale (Inserm) UMRS 1138, Centre de Recherche des Cordeliers, Paris, France (I.H., F.F.)
| | - Christian Stehlik
- Department of Pathology, Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, IL (C.S., E.B.T.)
| | - Sandrine Marchetti
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Laurent Boyer
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Rodolphe Guinamard
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
| | - Fabienne Foufelle
- Institut National de la Santé et de la Recherche Médicale (Inserm) UMRS 1138, Centre de Recherche des Cordeliers, Paris, France (I.H., F.F.)
| | | | | | - Edward B Thorp
- Department of Pathology, Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, IL (C.S., E.B.T.)
| | - Emmanuel L Gautier
- Institut National de la Santé et de la Recherche Médicale (INSERM) UMR_S 1166, Pierre & Marie Curie University, ICAN Institute of Cardiometabolism & Nutrition, Hôpital de la Pitié, Boulevard de l'Hôpital, Paris, France (I.D., E.L.G.)
| | - Dagmar Kratky
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Austria (N.V., M.D.-M., D.K.)
| | - Paul Dasilva-Jardine
- Academic Medical Center, Amsterdam, The Netherlands; and Staten Biotechnology, Nijmegen, The Netherlands (P.D.-J.)
| | - Laurent Yvan-Charvet
- From the Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Université Côte d'Azur, Centre Méditerranéen de Médecine Moléculaire (C3M), Atip-Avenir, Fédération Hospitalo-Universitaire (FHU) Oncoage, Nice, France (M.V., S.I., L.-E.A., E.G., S.M., L.B., R.G., L.Y.-C.)
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14
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Duta-Mare M, Sachdev V, Leopold C, Kolb D, Vujic N, Korbelius M, Hofer DC, Xia W, Huber K, Auer M, Gottschalk B, Magnes C, Graier WF, Prokesch A, Radovic B, Bogner-Strauss JG, Kratky D. Lysosomal acid lipase regulates fatty acid channeling in brown adipose tissue to maintain thermogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:467-478. [PMID: 29374543 DOI: 10.1016/j.bbalip.2018.01.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/02/2018] [Accepted: 01/22/2018] [Indexed: 02/07/2023]
Abstract
Lysosomal acid lipase (LAL) is the only known enzyme, which hydrolyzes cholesteryl esters and triacylglycerols in lysosomes of multiple cells and tissues. Here, we explored the role of LAL in brown adipose tissue (BAT). LAL-deficient (Lal-/-) mice exhibit markedly reduced UCP1 expression in BAT, modified BAT morphology with accumulation of lysosomes, and mitochondrial dysfunction, consequently leading to regular hypothermic events in mice kept at room temperature. Cold exposure resulted in reduced lipid uptake into BAT, thereby aggravating dyslipidemia and causing life threatening hypothermia in Lal-/- mice. Linking LAL as a potential regulator of lipoprotein lipase activity, we found Angptl4 mRNA expression upregulated in BAT. Our data demonstrate that LAL is critical for shuttling fatty acids derived from circulating lipoproteins to BAT during cold exposure. We conclude that inhibited lysosomal lipid hydrolysis in BAT leads to impaired thermogenesis in Lal-/- mice.
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Affiliation(s)
- Madalina Duta-Mare
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Vinay Sachdev
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Christina Leopold
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Dagmar Kolb
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Melanie Korbelius
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Dina C Hofer
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Wenmin Xia
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Katharina Huber
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Martina Auer
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | | | - Christoph Magnes
- Health, Bioanalytik und Metabolomics, Joanneum Research, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Andreas Prokesch
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Branislav Radovic
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Juliane G Bogner-Strauss
- Institute of Biochemistry, Graz University of Technology, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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15
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Bischof H, Rehberg M, Stryeck S, Artinger K, Eroglu E, Waldeck-Weiermair M, Gottschalk B, Rost R, Deak AT, Niedrist T, Vujic N, Lindermuth H, Prassl R, Pelzmann B, Groschner K, Kratky D, Eller K, Rosenkranz AR, Madl T, Plesnila N, Graier WF, Malli R. Novel genetically encoded fluorescent probes enable real-time detection of potassium in vitro and in vivo. Nat Commun 2017; 8:1422. [PMID: 29127288 PMCID: PMC5681659 DOI: 10.1038/s41467-017-01615-z] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/04/2017] [Indexed: 01/01/2023] Open
Abstract
Changes in intra- and extracellular potassium ion (K+) concentrations control many important cellular processes and related biological functions. However, our current understanding of the spatiotemporal patterns of physiological and pathological K+ changes is severely limited by the lack of practicable detection methods. We developed K+-sensitive genetically encoded, Förster resonance energy transfer-(FRET) based probes, called GEPIIs, which enable quantitative real-time imaging of K+ dynamics. GEPIIs as purified biosensors are suitable to directly and precisely quantify K+ levels in different body fluids and cell growth media. GEPIIs expressed in cells enable time-lapse and real-time recordings of global and local intracellular K+ signals. Hitherto unknown Ca2+-triggered, organelle-specific K+ changes were detected in pancreatic beta cells. Recombinant GEPIIs also enabled visualization of extracellular K+ fluctuations in vivo with 2-photon microscopy. Therefore, GEPIIs are relevant for diverse K+ assays and open new avenues for live-cell K+ imaging. K+ plays an important role in physiology and disease, but the lack of high specificity K+ sensors limits our understanding of its spatiotemporal dynamics. Here the authors develop genetically-encoded FRET-based probes able to quantify K+ concentration in body fluids, cells and specific organelles.
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Affiliation(s)
- Helmut Bischof
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Markus Rehberg
- Ludwig-Maximilians University (LMU), Institute for Stroke and Dementia Research (ISD), Klinikum der Universität München, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Sarah Stryeck
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Katharina Artinger
- Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, 8036, Graz, Austria
| | - Emrah Eroglu
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Markus Waldeck-Weiermair
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Benjamin Gottschalk
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Rene Rost
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Andras T Deak
- Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, 8036, Graz, Austria
| | - Tobias Niedrist
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Auenbruggerplatz 27, 8036, Graz, Austria
| | - Nemanja Vujic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria
| | - Hanna Lindermuth
- Institute of Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/4, 8010, Graz, Austria
| | - Ruth Prassl
- Institute of Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/4, 8010, Graz, Austria
| | - Brigitte Pelzmann
- Institute of Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/4, 8010, Graz, Austria
| | - Klaus Groschner
- Institute of Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/4, 8010, Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Kathrin Eller
- Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, 8036, Graz, Austria
| | - Alexander R Rosenkranz
- Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, 8036, Graz, Austria
| | - Tobias Madl
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Nikolaus Plesnila
- Ludwig-Maximilians University (LMU), Institute for Stroke and Dementia Research (ISD), Klinikum der Universität München, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Wolfgang F Graier
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Roland Malli
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010, Graz, Austria. .,BioTechMed-Graz, Graz, Austria.
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16
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Korbelius M, Obrowsky S, Rainer S, Vujic N, Kratky D. ATGL/CGI-58-dependent hydrolysis of a lipid storage pool in enterocytes. Atherosclerosis 2017. [DOI: 10.1016/j.atherosclerosis.2017.06.276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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17
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Schlager S, Vujic N, Korbelius M, Duta-Mare M, Dorow J, Leopold C, Rainer S, Wegscheider M, Reicher H, Ceglarek U, Sattler W, Radovic B, Kratky D. Lysosomal lipid hydrolysis provides substrates for lipid mediator synthesis in murine macrophages. Oncotarget 2017; 8:40037-40051. [PMID: 28402950 PMCID: PMC5522325 DOI: 10.18632/oncotarget.16673] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 03/19/2017] [Indexed: 11/25/2022] Open
Abstract
Degradation of lysosomal lipids requires lysosomal acid lipase (LAL), the only intracellular lipase known to be active at acidic pH. We found LAL to be expressed in murine immune cells with highest mRNA expression in macrophages and neutrophils. Furthermore, we observed that loss of LAL in mice caused lipid accumulation in white blood cells in the peripheral circulation, which increased in response to an acute inflammatory stimulus. Lal-deficient (-/-) macrophages accumulate neutral lipids, mainly cholesteryl esters, within lysosomes. The cholesteryl ester fraction is particularly enriched in the PUFAs 18:2 and 20:4, important precursor molecules for lipid mediator synthesis. To investigate whether loss of LAL activity affects the generation of lipid mediators and to eliminate potential systemic effects from other cells and tissues involved in the pronounced phenotype of Lal-/- mice, we treated macrophages from Wt mice with the LAL-specific inhibitor LAListat-2. Acute inhibition of LAL resulted in reduced release of 18:2- and 20:4-derived mediators from macrophages, indicating that lipid hydrolysis by LAL is an important source for lipid mediator synthesis in macrophages. We conclude that lysosomes should be considered as organelles that provide precursor molecules for lipid mediators such as eicosanoids.
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Affiliation(s)
- Stefanie Schlager
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- Boehringer Ingelheim, Vienna, Austria
| | - Nemanja Vujic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Melanie Korbelius
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Madalina Duta-Mare
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Juliane Dorow
- Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany
- LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany
| | - Christina Leopold
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Silvia Rainer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Martin Wegscheider
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Helga Reicher
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Uta Ceglarek
- Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany
- LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany
| | - Wolfgang Sattler
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Branislav Radovic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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18
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Vujic N, Schlager S, Eichmann TO, Madreiter-Sokolowski CT, Goeritzer M, Rainer S, Schauer S, Rosenberger A, Woelfler A, Doddapattar P, Zimmermann R, Hoefler G, Lass A, Graier WF, Radovic B, Kratky D. Monoglyceride lipase deficiency modulates endocannabinoid signaling and improves plaque stability in ApoE-knockout mice. Atherosclerosis 2015; 244:9-21. [PMID: 26584135 PMCID: PMC4704137 DOI: 10.1016/j.atherosclerosis.2015.10.109] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 10/27/2015] [Accepted: 10/28/2015] [Indexed: 12/25/2022]
Abstract
Background and aims Monoglyceride lipase (MGL) catalyzes the final step of lipolysis by degrading monoglyceride (MG) to glycerol and fatty acid. MGL also hydrolyzes and thereby deactivates 2-arachidonoyl glycerol (2-AG), the most abundant endocannabinoid in the mammalian system. 2-AG acts as full agonist on cannabinoid receptor type 1 (CB1R) and CB2R, which are mainly expressed in brain and immune cells, respectively. Thus, we speculated that in the absence of MGL, increased 2-AG concentrations mediate CB2R signaling in immune cells to modulate inflammatory responses, thereby affecting the development of atherosclerosis. Methods and results We generated apolipoprotein E (ApoE)/MGL double-knockout (DKO) mice and challenged them with Western-type diet for 9 weeks. Despite systemically increased 2-AG concentrations in DKO mice, CB2R-mediated signaling remains fully functional, arguing against CB2R desensitization. We found increased plaque formation in both en face aortae (1.3-fold, p = 0.028) and aortic valve sections (1.5-fold, p = 0.0010) in DKO mice. Interestingly, DKO mice also presented reduced lipid (12%, p = 0.031) and macrophage content (18%, p = 0.061), elevated intraplaque smooth muscle staining (1.4-fold, p = 0.016) and thicker fibrous caps (1.8-fold, p = 0.0032), together with a higher ratio of collagen to necrotic core area (2.5-fold, p = 0.0003) and expanded collagen content (1.6-fold, p = 0.0007), which suggest formation of less vulnerable atherosclerotic plaques. Treatment with a CB2R inverse agonist prevents these effects in DKO mice, demonstrating that the observed plaque phenotype in DKO mice originates from CB2R activation. Conclusion Loss of MGL modulates endocannabinoid signaling in CB2R-expressing cells, which concomitantly affects the pathogenesis of atherosclerosis. We conclude that despite larger lesion size loss of MGL improves atherosclerotic plaque stability. Thus, pharmacological MGL inhibition may be a novel intervention to reduce plaque rupture.
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Affiliation(s)
- Nemanja Vujic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Stefanie Schlager
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | | | - Madeleine Goeritzer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Silvia Rainer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Silvia Schauer
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | | | - Albert Woelfler
- Division of Hematology, Medical University of Graz, Graz, Austria
| | - Prakash Doddapattar
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Robert Zimmermann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Gerald Hoefler
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Wolfgang F Graier
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Branislav Radovic
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.
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19
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Goeritzer M, Vujic N, Schlager S, Chandak PG, Korbelius M, Gottschalk B, Leopold C, Obrowsky S, Rainer S, Doddapattar P, Aflaki E, Wegscheider M, Sachdev V, Graier WF, Kolb D, Radovic B, Kratky D. Active autophagy but not lipophagy in macrophages with defective lipolysis. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1304-1316. [PMID: 26143381 PMCID: PMC4562370 DOI: 10.1016/j.bbalip.2015.06.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 05/29/2015] [Accepted: 06/20/2015] [Indexed: 11/30/2022]
Abstract
During autophagy, autophagosomes fuse with lysosomes to degrade damaged organelles and misfolded proteins. Breakdown products are released into the cytosol and contribute to energy and metabolic building block supply, especially during starvation. Lipophagy has been defined as the autophagy-mediated degradation of lipid droplets (LDs) by lysosomal acid lipase. Adipose triglyceride lipase (ATGL) is the major enzyme catalyzing the initial step of lipolysis by hydrolyzing triglycerides (TGs) in cytosolic LDs. Consequently, most organs and cells, including macrophages, lacking ATGL accumulate TGs, resulting in reduced intracellular free fatty acid concentrations. Macrophages deficient in hormone-sensitive lipase (H0) lack TG accumulation albeit reduced in vitro TG hydrolase activity. We hypothesized that autophagy is activated in lipase-deficient macrophages to counteract their energy deficit. We therefore generated mice lacking both ATGL and HSL (A0H0). Macrophages from A0H0 mice showed 73% reduced neutral TG hydrolase activity, resulting in TG-rich LD accumulation. Increased expression of cathepsin B, accumulation of LC3-II, reduced expression of p62 and increased DQ-BSA dequenching suggest intact autophagy and functional lysosomes in A0H0 macrophages. Markedly decreased acid TG hydrolase activity and lipid flux independent of bafilomycin A1 treatment, however, argue against effective lysosomal degradation of LDs in A0H0 macrophages. We conclude that autophagy of proteins and cell organelles but not of LDs is active as a compensatory mechanism to circumvent and balance the reduced availability of energy substrates in A0H0 macrophages.
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Affiliation(s)
- Madeleine Goeritzer
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Nemanja Vujic
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Stefanie Schlager
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Prakash G Chandak
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Melanie Korbelius
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Benjamin Gottschalk
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Christina Leopold
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Sascha Obrowsky
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Silvia Rainer
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Prakash Doddapattar
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Elma Aflaki
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Martin Wegscheider
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Vinay Sachdev
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Wolfgang F Graier
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Dagmar Kolb
- Center for Medical Research/Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Branislav Radovic
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria
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20
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Schlager S, Goeritzer M, Jandl K, Frei R, Vujic N, Kolb D, Strohmaier H, Dorow J, Eichmann TO, Rosenberger A, Wölfler A, Lass A, Kershaw EE, Ceglarek U, Dichlberger A, Heinemann A, Kratky D. Adipose triglyceride lipase acts on neutrophil lipid droplets to regulate substrate availability for lipid mediator synthesis. J Leukoc Biol 2015; 98:837-50. [PMID: 26109679 PMCID: PMC4594763 DOI: 10.1189/jlb.3a0515-206r] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 06/09/2015] [Indexed: 01/18/2023] Open
Abstract
Lipid mediator release depends on the hydrolysis of triglyceride-rich lipid droplets mediated by ATGL, a potent regulator of inflammatory diseases. In humans, mutations in ATGL lead to TG accumulation in LDs of most tissues and cells, including peripheral blood leukocytes. This pathologic condition is called Jordans’ anomaly, in which functional consequences have not been investigated. In the present study, we tested the hypothesis that ATGL plays a role in leukocyte LD metabolism and immune cell function. Similar to humans with loss-of-function mutations in ATGL, we found that global and myeloid-specific Atgl−/− mice exhibit Jordans’ anomaly with increased abundance of intracellular TG-rich LDs in neutrophil granulocytes. In a model of inflammatory peritonitis, lipid accumulation was also observed in monocytes and macrophages but not in eosinophils or lymphocytes. Neutrophils from Atgl−/− mice showed enhanced immune responses in vitro, which were more prominent in cells from global compared with myeloid-specific Atgl−/− mice. Mechanistically, ATGL−/− as well as pharmacological inhibition of ATGL led to an impaired release of lipid mediators from neutrophils. These findings demonstrate that the release of lipid mediators is dependent on the liberation of precursor molecules from the TG-rich pool of LDs by ATGL. Our data provide mechanistic insights into Jordans’ anomaly in neutrophils and suggest that ATGL is a potent regulator of immune cell function and inflammatory diseases.
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Affiliation(s)
- Stefanie Schlager
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Madeleine Goeritzer
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Katharina Jandl
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Robert Frei
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Nemanja Vujic
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Dagmar Kolb
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Heimo Strohmaier
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Juliane Dorow
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Thomas O Eichmann
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Angelika Rosenberger
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Albert Wölfler
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Achim Lass
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Erin E Kershaw
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Uta Ceglarek
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Andrea Dichlberger
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Akos Heinemann
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Dagmar Kratky
- Institutes of *Molecular Biology and Biochemistry and Experimental and Clinical Pharmacology, Center for Medical Research, and Division of Hematology, Medical University of Graz, Graz, Austria; Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany; Institute of Molecular Biosciences, University of Graz, Graz, Austria; **Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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21
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Goeritzer M, Schlager S, Radovic B, Madreiter CT, Rainer S, Thomas G, Lord CC, Sacks J, Brown AL, Vujic N, Obrowsky S, Sachdev V, Kolb D, Chandak PG, Graier WF, Sattler W, Brown JM, Kratky D. Deletion of CGI-58 or adipose triglyceride lipase differently affects macrophage function and atherosclerosis. J Lipid Res 2014; 55:2562-75. [PMID: 25316883 PMCID: PMC4242449 DOI: 10.1194/jlr.m052613] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cellular TG stores are efficiently hydrolyzed by adipose TG lipase (ATGL). Its coactivator comparative gene identification-58 (CGI-58) strongly increases ATGL-mediated TG catabolism in cell culture experiments. To investigate the consequences of CGI-58 deficiency in murine macrophages, we generated mice with a targeted deletion of CGI-58 in myeloid cells (macCGI-58(-/-) mice). CGI-58(-/-) macrophages accumulate intracellular TG-rich lipid droplets and have decreased phagocytic capacity, comparable to ATGL(-/-) macrophages. In contrast to ATGL(-/-) macrophages, however, CGI-58(-/-) macrophages have intact mitochondria and show no indications of mitochondrial apoptosis and endoplasmic reticulum stress, suggesting that TG accumulation per se lacks a significant role in processes leading to mitochondrial dysfunction. Another notable difference is the fact that CGI-58(-/-) macrophages adopt an M1-like phenotype in vitro. Finally, we investigated atherosclerosis susceptibility in macCGI-58/ApoE-double KO (DKO) animals. In response to high-fat/high-cholesterol diet feeding, DKO animals showed comparable plaque formation as observed in ApoE(-/-) mice. In agreement, antisense oligonucleotide-mediated knockdown of CGI-58 in LDL receptor(-/-) mice did not alter atherosclerosis burden in the aortic root. These results suggest that macrophage function and atherosclerosis susceptibility differ fundamentally in these two animal models with disturbed TG catabolism, showing a more severe phenotype by ATGL deficiency.
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Affiliation(s)
- Madeleine Goeritzer
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Stefanie Schlager
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Branislav Radovic
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Corina T Madreiter
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Silvia Rainer
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Gwynneth Thomas
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, NC
| | - Caleb C Lord
- Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX
| | - Jessica Sacks
- Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | - Amanda L Brown
- Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | - Nemanja Vujic
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Sascha Obrowsky
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Vinay Sachdev
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Dagmar Kolb
- Center for Medical Research/Institute of Cell Biology, Histology, and Embryology, Medical University of Graz, Graz, Austria
| | - Prakash G Chandak
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Wolfgang F Graier
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - Wolfgang Sattler
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
| | - J Mark Brown
- Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
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