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Muturi HT, Ghadieh HE, Asalla S, Lester SG, Belew GD, Zaidi S, Abdolahipour R, Shrestha AP, Portuphy AO, Stankus HL, Helal RA, Verhulst S, Duarte S, Zarrinpar A, van Grunsven LA, Friedman SL, Schwabe RF, Hinds TD, Kumarasamy S, Najjar SM. Conditional deletion of CEACAM1 in hepatic stellate cells causes their activation. Mol Metab 2024; 88:102010. [PMID: 39168268 PMCID: PMC11403062 DOI: 10.1016/j.molmet.2024.102010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 07/24/2024] [Accepted: 08/09/2024] [Indexed: 08/23/2024] Open
Abstract
OBJECTIVES Hepatic CEACAM1 expression declines with advanced hepatic fibrosis stage in patients with metabolic dysfunction-associated steatohepatitis (MASH). Global and hepatocyte-specific deletions of Ceacam1 impair insulin clearance to cause hepatic insulin resistance and steatosis. They also cause hepatic inflammation and fibrosis, a condition characterized by excessive collagen production from activated hepatic stellate cells (HSCs). Given the positive effect of PPARγ on CEACAM1 transcription and on HSCs quiescence, the current studies investigated whether CEACAM1 loss from HSCs causes their activation. METHODS We examined whether lentiviral shRNA-mediated CEACAM1 donwregulation (KD-LX2) activates cultured human LX2 stellate cells. We also generated LratCre + Cc1fl/fl mutants with conditional Ceacam1 deletion in HSCs and characterized their MASH phenotype. Media transfer experiments were employed to examine whether media from mutant human and murine HSCs activate their wild-type counterparts. RESULTS LratCre + Cc1fl/fl mutants displayed hepatic inflammation and fibrosis but without insulin resistance or hepatic steatosis. Their HSCs, like KD-LX2 cells, underwent myofibroblastic transformation and their media activated wild-type HSCs. This was inhibited by nicotinic acid treatment which blunted the release of IL-6 and fatty acids, both of which activate the epidermal growth factor receptor (EGFR) tyrosine kinase. Gefitinib inhibition of EGFR and its downstream NF-κB/IL-6/STAT3 inflammatory and MAPK-proliferation pathways also blunted HSCs activation in the absence of CEACAM1. CONCLUSIONS Loss of CEACAM1 in HSCs provoked their myofibroblastic transformation in the absence of insulin resistance and hepatic steatosis. This response is mediated by autocrine HSCs activation of the EGFR pathway that amplifies inflammation and proliferation.
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Affiliation(s)
- Harrison T Muturi
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Hilda E Ghadieh
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA; Department of Biomedical Sciences, University of Balamand, Faculty of Medicine and Health Sciences, Al-Koura, Lebanon
| | - Suman Asalla
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Sumona G Lester
- Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA
| | - Getachew D Belew
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Sobia Zaidi
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Raziyeh Abdolahipour
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Abhishek P Shrestha
- Department of Surgery, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Agnes O Portuphy
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Hannah L Stankus
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Raghd Abu Helal
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Stefaan Verhulst
- Liver Cell Biology Research Group, Vrije Universiteit Brussel, Brussel, Belgium
| | - Sergio Duarte
- Department of Surgery, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Ali Zarrinpar
- Department of Surgery, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Leo A van Grunsven
- Liver Cell Biology Research Group, Vrije Universiteit Brussel, Brussel, Belgium
| | - Scott L Friedman
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York 10029, NY, USA
| | - Robert F Schwabe
- Department of Medicine and the Digestive and Liver Disease Research Center, Columbia University New York, NY, USA
| | - Terry D Hinds
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Sivarajan Kumarasamy
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Sonia M Najjar
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA; Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
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Wilhelmsen I, Combriat T, Dalmao-Fernandez A, Stokowiec J, Wang C, Olsen PA, Wik JA, Boichuk Y, Aizenshtadt A, Krauss S. The effects of TGF-β-induced activation and starvation of vitamin A and palmitic acid on human stem cell-derived hepatic stellate cells. Stem Cell Res Ther 2024; 15:223. [PMID: 39044210 PMCID: PMC11267759 DOI: 10.1186/s13287-024-03852-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 07/14/2024] [Indexed: 07/25/2024] Open
Abstract
BACKGROUND Hepatic stellate cells (HSC) have numerous critical roles in liver function and homeostasis, while they are also known for their importance during liver injury and fibrosis. There is therefore a need for relevant in vitro human HSC models to fill current knowledge gaps. In particular, the roles of vitamin A (VA), lipid droplets (LDs), and energy metabolism in human HSC activation are poorly understood. METHODS In this study, human pluripotent stem cell-derived HSCs (scHSCs), benchmarked to human primary HSC, were exposed to 48-hour starvation of retinol (ROL) and palmitic acid (PA) in the presence or absence of the potent HSC activator TGF-β. The interventions were studied by an extensive set of phenotypic and functional analyses, including transcriptomic analysis, measurement of activation-related proteins and cytokines, VA- and LD storage, and cell energy metabolism. RESULTS The results show that though the starvation of ROL and PA alone did not induce scHSC activation, the starvation amplified the TGF-β-induced activation-related transcriptome. However, TGF-β-induced activation alone did not lead to a reduction in VA or LD stores. Additionally, reduced glycolysis and increased mitochondrial fission were observed in response to TGF-β. CONCLUSIONS scHSCs are robust models for activation studies. The loss of VA and LDs is not sufficient for scHSC activation in vitro, but may amplify the TGF-β-induced activation response. Collectively, our work provides an extensive framework for studying human HSCs in healthy and diseased conditions.
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Affiliation(s)
- Ingrid Wilhelmsen
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway.
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway.
| | - Thomas Combriat
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Andrea Dalmao-Fernandez
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, P.O. Box 1068, Blindern, Oslo, 0316, Norway
| | - Justyna Stokowiec
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Chencheng Wang
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
- Department of Transplantation Medicine, Institute for Surgical Research, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
| | - Petter Angell Olsen
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Jonas Aakre Wik
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Yuliia Boichuk
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Aleksandra Aizenshtadt
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
| | - Stefan Krauss
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, Oslo, 0424, Norway
- Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1110, Blindern, Oslo, 0317, Norway
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Reese-Petersen AL, Holm Nielsen S, Bülow Sand JM, Schattenberg JM, Bugianesi E, Karsdal MA. The sclerotic component of metabolic syndrome: Fibroblast activities may be the central common denominator driving organ function loss and death. Diabetes Obes Metab 2024; 26:2554-2566. [PMID: 38699780 DOI: 10.1111/dom.15615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/09/2024] [Accepted: 04/09/2024] [Indexed: 05/05/2024]
Abstract
Fibrosis is a common feature of more than 50 different diseases and the cause of more than 35% of deaths worldwide, of which liver, kidney, skin, heart and, recently, lungs are receiving the most attention. Tissue changes, resulting in loss of organ function, are both a cause and consequence of disease and outcome. Fibrosis is caused by an excess deposition of extracellular matrix proteins, which over time results in impaired organ function and organ failure, and the pathways leading to increased fibroblast activation are many. This narrative review investigated the common denominator of fibrosis, fibroblasts, and the activation of fibroblasts, in response to excess energy consumption in liver, kidney, heart, skin and lung fibrosis. Fibroblasts are the main drivers of organ function loss in lung, liver, skin, heart and kidney disease. Fibroblast activation in response to excess energy consumption results in the overproduction of a range of collagens, of which types I, III and VI seem to be the essential drivers of disease progression. Fibroblast activation may be quantified in serum, enabling profiling and selection of patients. Activation of fibroblasts results in the overproduction of collagens, which deteriorates organ function. Patient profiling of fibroblast activities in serum, quantified as collagen production, may identify an organ death trajectory, better enabling identification of the right treatment for use in different metabolic interventions. As metabolically activated patients have highly elevated risk of kidney, liver and heart failure, it is essential to identify which organ to treat first and monitor organ status to correct treatment regimes. In direct alignment with this, it is essential to identify the right patients with the right organ deterioration trajectory for enrolment in clinical studies.
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Affiliation(s)
| | | | | | - Jörn M Schattenberg
- Saarland University Medical Center, Homburg, Germany
- University of the Saarland, Saarbrücken, Germany
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Muturi HT, Ghadieh HE, Asalla S, Lester SG, Verhulst S, Stankus HL, Zaidi S, Abdolahipour R, Belew GD, van Grunsven LA, Friedman SL, Schwabe RF, Hinds TD, Najjar SM. Conditional deletion of CEACAM1 causes hepatic stellate cell activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.02.586238. [PMID: 38617330 PMCID: PMC11014538 DOI: 10.1101/2024.04.02.586238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Objectives Hepatic CEACAM1 expression declines with advanced hepatic fibrosis stage in patients with MASH. Global and hepatocyte-specific deletions of Ceacam1 impair insulin clearance to cause hepatic insulin resistance and steatosis. They also cause hepatic inflammation and fibrosis, a condition characterized by excessive collagen production from activated hepatic stellate cells (HSCs). Given the positive effect of PPARγ on CEACAM1 transcriptoin and on HSCs quiescence, the current studies investigated whether CEACAM1 loss from HSCs causes their activation. Methods We examined whether lentiviral shRNA-mediated CEACAM1 donwregulation (KD-LX2) activates cultured human LX2 stellate cells. We also generated LratCre+Cc1 fl/fl mutants with conditional Ceacam1 deletion in HSCs and characterized their MASH phenotype. Media transfer experiments were employed to examine whether media from mutant human and murine HSCs activate their wild-type counterparts. Results LratCre+Cc1 fl/fl mutants displayed hepatic inflammation and fibrosis but without insulin resistance or hepatic steatosis. Their HSCs, like KD-LX2 cells, underwent myofibroblastic transformation and their media activated wild-type HDCs. This was inhibited by nicotinic acid treatment which stemmed the release of IL-6 and fatty acids, both of which activate the epidermal growth factor receptor (EGFR) tyrosine kinase. Gefitinib inhibition of EGFR and its downstream NF-κB/IL-6/STAT3 inflammatory and MAPK-proliferation pathways also blunted HSCs activation in the absence of CEACAM1. Conclusions Loss of CEACAM1 in HSCs provoked their myofibroblastic transformation in the absence of insulin resistance and hepatic steatosis. This response is mediated by autocrine HSCs activation of the EGFR pathway that amplifies inflammation and proliferation.
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Campos-Espinosa A, Guzmán C, Medina-Ávila KZ, Gutierrez-Reyes G. In Vitro Lipid Overload Affects Cellular Proliferation, Apoptosis, and Senescence in a Time-Dependent Manner in HepG2 Hepatocytes and LX-2 Hepatic Stellate Cells. Cells 2024; 13:282. [PMID: 38334674 PMCID: PMC10854820 DOI: 10.3390/cells13030282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/10/2024] Open
Abstract
Different cellular mechanisms influence steatotic liver disease (SLD) progression. The influence of different levels of steatogenic inputs has not been studied in hepatocytes and hepatic stellate cells (HSCs). METHODS HepG2 hepatocytes and LX-2 HSCs were cultured in mild (MS) and severe (SS) steatogenic conditions. TGF-β stimulation was also tested for HSCs in control (T) and steatogenic conditions (MS-T and SS-T). Steatosis was stained with Oil Red, and the proliferation was assayed via WST-8 reduction, apoptosis via flow cytometry, and senescence via SA-β-galactosidase activity. RESULTS Regarding hepatocytes, steatosis progressively increased; proliferation was lower in MS and SS; and the viability of both conditions significantly decreased at 72 h. Apoptosis increased in MS at 72 h, while it decreased in SS. Senescence increased in MS and diminished in SS. Regarding HSCs, the SS and SS-T groups showed no proliferation, and the viability was reduced in MS at 72 h and in SS and SS-T. The LX-2 cells showed increased apoptosis in SS and SS-T at 24 h, and in MS and MS-T at 72 h. Senescence decreased in MS, SS, and SS-T. CONCLUSIONS Lipid overload induces differential effects depending on the cell type, the steatogenic input level, and the exposure time. Hepatocytes are resilient to mild steatosis but susceptible to high lipotoxicity. HSCs are sensitive to lipid overload, undergoing apoptosis and lowering senescence and proliferation. Collectively, these data may help explain the development of steatosis and fibrosis in SLD.
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Affiliation(s)
| | | | | | - Gabriela Gutierrez-Reyes
- Laboratorio de Hígado, Páncreas y Motilidad, Unidad de Medicina Experimental, Facultad de Medicina, UNAM, Hospital General de México “Dr. Eduardo Liceaga”, Ciudad de México 06720, Mexico; (A.C.-E.); (C.G.); (K.Z.M.-Á.)
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Dudgeon C, Casabianca A, Harris C, Ogier C, Bellina M, Fiore S, Bernet A, Ducarouge B, Goldschneider D, Su X, Pitarresi J, Hezel A, De S, Narrow W, Soliman F, Shields C, Vendramini-Costa DB, Prela O, Wang L, Astsaturov I, Mehlen P, Carpizo DR. Netrin-1 feedforward mechanism promotes pancreatic cancer liver metastasis via hepatic stellate cell activation, retinoid, and ELF3 signaling. Cell Rep 2023; 42:113369. [PMID: 37922311 DOI: 10.1016/j.celrep.2023.113369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 09/04/2023] [Accepted: 10/18/2023] [Indexed: 11/05/2023] Open
Abstract
The biology of metastatic pancreatic ductal adenocarcinoma (PDAC) is distinct from that of the primary tumor due to changes in cell plasticity governed by a distinct transcriptome. Therapeutic strategies that target this distinct biology are needed. We detect an upregulation of the neuronal axon guidance molecule Netrin-1 in PDAC liver metastases that signals through its dependence receptor (DR), uncoordinated-5b (Unc5b), to facilitate metastasis in vitro and in vivo. The mechanism of Netrin-1 induction involves a feedforward loop whereby Netrin-1 on the surface of PDAC-secreted extracellular vesicles prepares the metastatic niche by inducing hepatic stellate cell activation and retinoic acid secretion that in turn upregulates Netrin-1 in disseminated tumor cells via RAR/RXR and Elf3 signaling. While this mechanism promotes PDAC liver metastasis, it also identifies a therapeutic vulnerability, as it can be targeted using anti-Netrin-1 therapy to inhibit metastasis using the Unc5b DR cell death mechanism.
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Affiliation(s)
- Crissy Dudgeon
- Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Anthony Casabianca
- Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Center, University of Rochester, Rochester, NY, USA
| | - Chris Harris
- Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Center, University of Rochester, Rochester, NY, USA
| | - Charline Ogier
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Mélanie Bellina
- Apoptosis, Cancer and Development Laboratory - Equipe labellisée "La Ligue," LabEx DEVweCAN, Institut Convergence PLAsCAN, Centre de Recherche en Cancérologie de Lyon (CRCL), INSERM U1052-CNRS UMR5286, Université de Lyon, Université Claude Bernard Lyon 1, Centre Léon Bérard, 69008 Lyon, France; Netris Pharma, 69008 Lyon, France
| | - Stephany Fiore
- Apoptosis, Cancer and Development Laboratory - Equipe labellisée "La Ligue," LabEx DEVweCAN, Institut Convergence PLAsCAN, Centre de Recherche en Cancérologie de Lyon (CRCL), INSERM U1052-CNRS UMR5286, Université de Lyon, Université Claude Bernard Lyon 1, Centre Léon Bérard, 69008 Lyon, France
| | - Agnes Bernet
- Apoptosis, Cancer and Development Laboratory - Equipe labellisée "La Ligue," LabEx DEVweCAN, Institut Convergence PLAsCAN, Centre de Recherche en Cancérologie de Lyon (CRCL), INSERM U1052-CNRS UMR5286, Université de Lyon, Université Claude Bernard Lyon 1, Centre Léon Bérard, 69008 Lyon, France; Netris Pharma, 69008 Lyon, France
| | | | | | - Xiaoyang Su
- Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Jason Pitarresi
- Department of Medicine, Division of Hematology/Oncology, University of Massachusetts, Worcester, MA, USA
| | - Aram Hezel
- Department of Medicine, Division of Medical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Subhajyoti De
- Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Wade Narrow
- Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Center, University of Rochester, Rochester, NY, USA
| | - Fady Soliman
- Rutgers Robert Wood-Johnson Medical School, New Brunswick, NJ, USA
| | - Cory Shields
- Wilmot Cancer Center, University of Rochester, Rochester, NY, USA
| | | | - Orjola Prela
- Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Lan Wang
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Igor Astsaturov
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Patrick Mehlen
- Apoptosis, Cancer and Development Laboratory - Equipe labellisée "La Ligue," LabEx DEVweCAN, Institut Convergence PLAsCAN, Centre de Recherche en Cancérologie de Lyon (CRCL), INSERM U1052-CNRS UMR5286, Université de Lyon, Université Claude Bernard Lyon 1, Centre Léon Bérard, 69008 Lyon, France; Netris Pharma, 69008 Lyon, France
| | - Darren R Carpizo
- Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Center, University of Rochester, Rochester, NY, USA.
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Mak KM, Wu C, Cheng CP. Lipid droplets, the Holy Grail of hepatic stellate cells: In health and hepatic fibrosis. Anat Rec (Hoboken) 2022; 306:983-1010. [PMID: 36516055 DOI: 10.1002/ar.25138] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/07/2022] [Accepted: 11/29/2022] [Indexed: 12/15/2022]
Abstract
Lipid droplets (LDs) are distinct morphological markers of hepatic stellate cells (HSCs). They are composed of a core of predominantly retinyl esters and triacylglycerols surrounded by a phospholipid layer; the latter harbors perilipins 2, 3, and 5, which help control LD lipolysis. Electron microscopy distinguishes between Types I and II LDs. Type I LDs are surrounded by acid phosphatase-positive lysosomes, which likely digest LDs. LD count and retinoid concentration are modulated by vitamin A intake. Alcohol consumption depletes hepatic retinoids and HSC LDs, with concomitant transformation of HSCs to fibrogenic myofibroblast-like cells. LD loss and accompanying HSC activation occur in HSC cell culture models. Loss of LDs is a consequence of and not a prerequisite for HSC activation. LDs are endowed with enzymes for synthesizing retinyl esters and triacylglycerols as well as neutral lipases and lysosomal acid lipase for breaking down LDs. HSCs have two distinct metabolic LD pools: an "original" pool in quiescent HSCs and a "new" pool emerging in HSC activation; this two-pool model provides a platform for analyzing LD dynamics in HSC activation. Besides lipolysis, LDs are degraded by lipophagy; however, the coordination between and relative contributions of these two pathways to LD removal are unclear. While induction of autophagy accelerates LD loss in quiescent HSCs and promotes HSC activation, blocking autophagy impairs LD degradation and inhibits HSC activation and fibrosis. This article is a critique of five decades of investigations into the morphology, molecular structure, synthesis, and degradation of LDs associated with HSC activation and fibrosis.
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Affiliation(s)
- Ki M Mak
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Catherine Wu
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Christopher P Cheng
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Physical Interaction between Embryonic Stem Cell-Expressed Ras (ERas) and Arginase-1 in Quiescent Hepatic Stellate Cells. Cells 2022; 11:cells11030508. [PMID: 35159317 PMCID: PMC8834437 DOI: 10.3390/cells11030508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/18/2022] [Accepted: 01/27/2022] [Indexed: 12/20/2022] Open
Abstract
Embryonic stem cell-expressed Ras (ERas) is an atypical constitutively active member of the Ras family and controls distinct signaling pathways, which are critical, for instance, for the maintenance of quiescent hepatic stellate cells (HSCs). Unlike classical Ras paralogs, ERas has a unique N-terminal extension (Nex) with as yet unknown function. In this study, we employed affinity pull-down and quantitative liquid chromatography-tandem mass spectrometry (LC–MS/MS) analyses and identified 76 novel binding proteins for human and rat ERas Nex peptides, localized in different subcellular compartments and involved in various cellular processes. One of the identified Nex-binding proteins is the nonmitochondrial, cytosolic arginase 1 (ARG1), a key enzyme of the urea cycle and involved in the de novo synthesis of polyamines, such as spermidine and spermine. Here, we show, for the first time, a high-affinity interaction between ERas Nex and purified ARG1 as well as their subcellular colocalization. The inhibition of ARG1 activity strikingly accelerates the activation of HSCs ex vivo, suggesting a central role of ARG1 activity in the maintenance of HSC quiescence.
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9
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Rosenthal SB, Liu X, Ganguly S, Dhar D, Pasillas MP, Ricciardelli E, Li RZ, Troutman TD, Kisseleva T, Glass CK, Brenner DA. Heterogeneity of HSCs in a Mouse Model of NASH. Hepatology 2021; 74:667-685. [PMID: 33550587 PMCID: PMC8346581 DOI: 10.1002/hep.31743] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/24/2020] [Accepted: 12/23/2020] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND AIMS In clinical and experimental NASH, the origin of the scar-forming myofibroblast is the HSC. We used foz/foz mice on a Western diet to characterize in detail the phenotypic changes of HSCs in a NASH model. APPROACH AND RESULTS We examined the single-cell expression profiles (scRNA sequencing) of HSCs purified from the normal livers of foz/foz mice on a chow diet, in NASH with fibrosis of foz/foz mice on a Western diet, and in livers during regression of NASH after switching back to a chow diet. Selected genes were analyzed using immunohistochemistry, quantitative real-time PCR, and short hairpin RNA knockdown in primary mouse HSCs. Our analysis of the normal liver identified two distinct clusters of quiescent HSCs that correspond to their acinar position of either pericentral vein or periportal vein. The NASH livers had four distinct HSC clusters, including one representing the classic fibrogenic myofibroblast. The three other HSC clusters consisted of a proliferating cluster, an intermediate activated cluster, and an immune and inflammatory cluster. The livers with NASH regression had one cluster of inactivated HSCs, which was similar to, but distinct from, the quiescent HSCs. CONCLUSIONS Analysis of single-cell RNA sequencing in combination with an interrogation of previous studies revealed an unanticipated heterogeneity of HSC phenotypes under normal and injured states.
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Affiliation(s)
- Sara Brin Rosenthal
- Center for Computational Biology and BioinformaticsUniversity of California, San DiegoLa JollaCA.,Department of MedicineUniversity of California, San DiegoLa JollaCA
| | - Xiao Liu
- Department of MedicineUniversity of California, San DiegoLa JollaCA.,Department of SurgeryUniversity of California, San DiegoLa JollaCA
| | | | - Debanjan Dhar
- Department of MedicineUniversity of California, San DiegoLa JollaCA
| | - Martina P Pasillas
- Department of Cellular and Molecular MedicineUniversity of California, San DiegoLa JollaCA
| | | | - Rick Z Li
- Department of Cellular and Molecular MedicineUniversity of California, San DiegoLa JollaCA
| | - Ty D Troutman
- Department of MedicineUniversity of California, San DiegoLa JollaCA
| | | | - Christopher K Glass
- Department of MedicineUniversity of California, San DiegoLa JollaCA.,Department of Cellular and Molecular MedicineUniversity of California, San DiegoLa JollaCA
| | - David A Brenner
- Department of MedicineUniversity of California, San DiegoLa JollaCA
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Rockey DC, Friedman SL. Fibrosis Regression After Eradication of Hepatitis C Virus: From Bench to Bedside. Gastroenterology 2021; 160:1502-1520.e1. [PMID: 33529675 PMCID: PMC8601597 DOI: 10.1053/j.gastro.2020.09.065] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/01/2020] [Accepted: 09/06/2020] [Indexed: 02/06/2023]
Abstract
Hepatitis C virus (HCV) infection and its complications have been the major cause of cirrhosis and its complications for several decades in the Western world. Until recently, treatment for HCV with interferon-based regimens was associated with moderate success but was difficult to tolerate. More recently, however, an arsenal of novel and highly effective direct-acting antiviral (DAA) drugs has transformed the landscape by curing HCV in a broad range of patients, including those with established advanced fibrosis, cirrhosis, comorbidities, and even those with complications of cirrhosis. Fibrosis is a dynamic process comprising both extracellular matrix deposition, as well as its degradation. With almost universal sustained virologic response (SVR) (ie, elimination of HCV), it is timely to explore whether HCV eradication can reverse fibrosis and cirrhosis. Indeed, fibrosis in several types of liver disease is reversible, including HCV. However, we do not know with certainty in whom fibrosis regression can be expected after HCV elimination, how quickly it occurs, and whether antifibrotic therapies will be indicated in those with persistent cirrhosis. This review summarizes the evidence for reversibility of fibrosis and cirrhosis after HCV eradication, its impact on clinical outcomes, and therapeutic prospects for directly promoting fibrosis regression in patients whose fibrosis persists after SVR.
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Affiliation(s)
- Don C Rockey
- The Medical University of South Carolina, Charleston, South Carolina.
| | - Scott L Friedman
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
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Hepatic Stellate Cell Activation and Inactivation in NASH-Fibrosis-Roles as Putative Treatment Targets? Biomedicines 2021; 9:biomedicines9040365. [PMID: 33807461 PMCID: PMC8066583 DOI: 10.3390/biomedicines9040365] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 03/25/2021] [Accepted: 03/27/2021] [Indexed: 02/07/2023] Open
Abstract
Hepatic fibrosis is the primary predictor of mortality in patients with non-alcoholic steatohepatitis (NASH). In this process, the activated hepatic stellate cells (HSCs) constitute the principal cells responsible for the deposition of a fibrous extracellular matrix, thereby driving the hepatic scarring. HSC activation, migration, and proliferation are controlled by a complex signaling network involving growth factors, lipotoxicity, inflammation, and cellular stress. Conversely, the clearance of activated HSCs is a prerequisite for the resolution of the extracellular fibrosis. Hence, pathways regulating the fate of the HSCs may represent attractive therapeutic targets for the treatment and prevention of NASH-associated hepatic fibrosis. However, the development of anti-fibrotic drugs for NASH patients has not yet resulted in clinically approved therapeutics, underscoring the complex biology and challenges involved when targeting the intricate cellular signaling mechanisms. This narrative review investigated the mechanisms of activation and inactivation of HSCs with a focus on NASH-associated hepatic fibrosis. Presenting an updated overview, this review highlights key cellular pathways with potential value for the development of future treatment modalities.
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Faulkner CS, White CM, Shah VH, Jophlin LL. A single nucleotide polymorphism of PLIN2 is associated with nonalcoholic steatohepatitis and causes phenotypic changes in hepatocyte lipid droplets: A pilot study. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158637. [PMID: 31981756 PMCID: PMC8108536 DOI: 10.1016/j.bbalip.2020.158637] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/16/2020] [Accepted: 01/21/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Claire S Faulkner
- University of Nebraska Medical Center (UNMC), Department of Internal Medicine, Omaha, NE, United States of America; Mayo Clinic, Division of Gastroenterology and Hepatology, Rochester, MN, United States of America
| | - Collin M White
- Washington University, St. Louis, MO, United States of America
| | - Vijay H Shah
- Mayo Clinic, Division of Gastroenterology and Hepatology, Rochester, MN, United States of America
| | - Loretta L Jophlin
- University of Nebraska Medical Center (UNMC), Department of Internal Medicine, Omaha, NE, United States of America; Mayo Clinic, Division of Gastroenterology and Hepatology, Rochester, MN, United States of America.
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Silva CM, Ferrari GD, Alberici LC, Malaspina O, Moraes KCM. Cellular and molecular effects of silymarin on the transdifferentiation processes of LX-2 cells and its connection with lipid metabolism. Mol Cell Biochem 2020; 468:129-142. [PMID: 32185674 DOI: 10.1007/s11010-020-03717-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/06/2020] [Indexed: 12/17/2022]
Abstract
Fibrosis process in the liver is a clinical condition established in response to chronic lesions and may be reversible in many situations. In this process, hepatic stellate cells (HSCs) activate and produce extracellular matrix compounds. During fibrosis, the lipid metabolism is also altered and contributes to the transdifferentiation of the HSCs. Thus, controlling lipid metabolism in HSCs is suggested as a method to control or reverse the fibrotic condition. In the search for therapies that modulate lipid metabolism and treat liver diseases, silymarin has been identified as a relevant natural compound to treat liver pathologies. The present study aimed to evaluate the cellular and molecular effects of silymarin in the transdifferentiation process of HSCs (LX-2) from activated phenotype to a more quiesced-like cells , also focusing on understanding the modulatory effects of silymarin on lipid metabolism of HSCs. In our analyses, 100 µM of silymarin reduced the synthesis of actin filaments in activated cells, the synthesis of the protein level of α-SMA, and other pro-fibrotic factors such as CTGF and PFGF. The concentration of 150 µM silymarin did not reverse the activation aspects of LX-2 cells. However, both evaluated concentrations of the natural compound protected the cells from the negative effects of dimethyl sulfoxide (DMSO). Furthermore, we evaluated lipid-related molecules correlated to the transdifferentiation process of LX-2, and 100 µM of silymarin demonstrated to control molecules associated with lipid metabolism such as FASN, MLYCD, ACSL4, CPTs, among others. In contrast, cellular incubation with 150 µM of silymarin increased the synthesis of long-chain fatty acids and triglycerides, regarding the higher presence of DMSO (v/v) in the solvent. In conclusion, silymarin acts as a hepatoprotective agent and modulates the pro-fibrogenic stimuli of LX-2 cells, whose effects depend on stress levels in the cellular environment.
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Affiliation(s)
- Caio Mateus Silva
- Laboratório de Biologia Molecular, Departamento de Biologia Geral e Aplicada, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Rio Claro, SP, 13506-900, Brazil
| | - Gustavo Duarte Ferrari
- Departamento de Bioquímica E Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, USP, Ribeirão Preto, SP, Brazil
| | - Luciane Carla Alberici
- Departamento de Física E Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, USP, Ribeirão Preto, SP, Brazil
| | - Osmar Malaspina
- Centro de Estudos de Insetos Sociais, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Rio Claro, SP, Brazil
| | - Karen C M Moraes
- Laboratório de Biologia Molecular, Departamento de Biologia Geral e Aplicada, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Rio Claro, SP, 13506-900, Brazil.
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Hepatic stellate cell hypertrophy is associated with metabolic liver fibrosis. Sci Rep 2020; 10:3850. [PMID: 32123215 PMCID: PMC7052210 DOI: 10.1038/s41598-020-60615-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 02/14/2020] [Indexed: 02/07/2023] Open
Abstract
Hepatic fibrosis is a major consequence of chronic liver disease such as non-alcoholic steatohepatitis which is undergoing a dramatic evolution given the obesity progression worldwide, and has no treatment to date. Hepatic stellate cells (HSCs) play a key role in the fibrosis process, because in chronic liver damage, they transdifferentiate from a “quiescent” to an “activated” phenotype responsible for most the collagen deposition in liver tissue. Here, using a diet-induced liver fibrosis murine model (choline-deficient amino acid-defined, high fat diet), we characterized a specific population of HSCs organized as clusters presenting simultaneously hypertrophy of retinoid droplets, quiescent and activated HSC markers. We showed that hypertrophied HSCs co-localized with fibrosis areas in space and time. Importantly, we reported the existence of this phenotype and its association with collagen deposition in three other mouse fibrosis models, including CCl4-induced fibrosis model. Moreover, we have also shown its relevance in human liver fibrosis associated with different etiologies (obesity, non-alcoholic steatohepatitis, viral hepatitis C and alcoholism). In particular, we have demonstrated a significant positive correlation between the stage of liver fibrosis and HSC hypertrophy in a cohort of obese patients with hepatic fibrosis. These results lead us to conclude that hypertrophied HSCs are closely associated with hepatic fibrosis in a metabolic disease context and may represent a new marker of metabolic liver disease progression.
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Synergy of Phospholipid-Drug Formulations Significantly Deactivates Profibrogenic Human Hepatic Stellate Cells. Pharmaceutics 2019; 11:pharmaceutics11120676. [PMID: 31842373 PMCID: PMC6969915 DOI: 10.3390/pharmaceutics11120676] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 02/06/2023] Open
Abstract
The pivotal role of hepatic stellate cells (HSCs) in orchestrating the bidirectional process of progression and regression of liver fibrosis makes them an ideal target for exploring new antifibrotic therapies. Essential phospholipids (EPLs), with their polyenylphosphatidylcholine (PPC) fraction, either alone or combined with other hepatoprotective substances such as silymarin, are recommended in hepatic impairment, but a scientific rationale for their use is still lacking. Herein, we compared the ability of EPLs to restore quiescent-like features in HSCs with that of dilinoleoylphosphatidylcholine (DLPC), PPC fraction’s main component. Specifically, we screened at the cellular level the antifibrotic effects of PPC formulations in the presence and absence of silymarin, by using LX-2 cells (pro-fibrogenic HSCs) and by assessing the main biochemical hallmarks of the activated and deactivated states of this cell line. We also proved the formulations’ direct effect on the motional order of cell membranes of adherent cells. LX-2 cells, examined for lipid droplets as a quiescence marker, showed that PPCs led to a more prominent deactivation than DLPC. This result was confirmed by a reduction of collagen and α-SMA expression, and by a profound alteration in the cell membrane fluidity. PPC–silymarin formulations deactivated HSCs with a significant synergistic effect. The remarkable bioactivity of PPCs in deactivating fibrogenic HSCs paves the way for the rational design of new therapeutics aimed at managing hepatic fibrosis.
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Wang S, Yu J, Kane MA, Moise AR. Modulation of retinoid signaling: therapeutic opportunities in organ fibrosis and repair. Pharmacol Ther 2019; 205:107415. [PMID: 31629008 DOI: 10.1016/j.pharmthera.2019.107415] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 09/17/2019] [Indexed: 02/08/2023]
Abstract
The vitamin A metabolite, retinoic acid, is an important signaling molecule during embryonic development serving critical roles in morphogenesis, organ patterning and skeletal and neural development. Retinoic acid is also important in postnatal life in the maintenance of tissue homeostasis, while retinoid-based therapies have long been used in the treatment of a variety of cancers and skin disorders. As the number of people living with chronic disorders continues to increase, there is great interest in extending the use of retinoid therapies in promoting the maintenance and repair of adult tissues. However, there are still many conflicting results as we struggle to understand the role of retinoic acid in the multitude of processes that contribute to tissue injury and repair. This review will assess our current knowledge of the role retinoic acid signaling in the development of fibroblasts, and their transformation to myofibroblasts, and of the potential use of retinoid therapies in the treatment of organ fibrosis.
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Affiliation(s)
- Suya Wang
- Department of Cardiology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - Jianshi Yu
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, 21201, USA
| | - Maureen A Kane
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, 21201, USA.
| | - Alexander R Moise
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, ON P3E 2C6, Canada; Departments of Chemistry and Biochemistry, and Biology and Biomolecular Sciences Program, Laurentian University, Sudbury, ON, P3E 2C6, Canada.
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Rockey DC, Du Q, Weymouth ND, Shi Z. Smooth Muscle α-Actin Deficiency Leads to Decreased Liver Fibrosis via Impaired Cytoskeletal Signaling in Hepatic Stellate Cells. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:2209-2220. [PMID: 31476284 DOI: 10.1016/j.ajpath.2019.07.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/03/2019] [Accepted: 07/29/2019] [Indexed: 01/18/2023]
Abstract
In the liver, smooth muscle α-actin (SM α-actin) is up-regulated in hepatic stellate cells (HSCs) as they transition to myofibroblasts during liver injury and the wound healing response. Whether SM α-actin has specific functional effects on cellular effectors of fibrosis such as HSC is controversial. Here, the relationship between SM α-actin and type 1 collagen expression (COL1A1), a major extracellular matrix protein important in liver fibrosis, is investigated with the results demonstrating that knockout of SM α-actin leads to reduced liver fibrosis and COL1 expression. The mechanism for the reduction in fibrogenesis in vivo is multifactorial, including not only a reduction in the number of HSCs, but also an HSC-specific reduction in COL1 expression in Acta2-deficient HSCs. Despite a compensatory increase in expression of cytoplasmic β-actin and γ-actin isoforms in Acta2-/- HSCs, defects were identified in each transforming growth factor beta/Smad2/3 and ET-1/Erk1/2 signaling in Acta2-/- HSCs. These data not only suggest a molecular link between the SM α-actin cytoskeleton and classic fibrogenic signaling cascades, but also emphasize the relationship between SM α-actin and fibrogenesis in hepatic myofibroblasts in vivo.
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Affiliation(s)
- Don C Rockey
- Department of Internal Medicine, Medical University of South Carolina, Charleston, South Carolina.
| | - Qinghong Du
- Department of Internal Medicine, Medical University of South Carolina, Charleston, South Carolina
| | | | - Zengdun Shi
- Department of Internal Medicine, Medical University of South Carolina, Charleston, South Carolina.
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Abstract
Lipid droplets (LDs) are key sites of neutral lipid storage that can be found in all cells. Metabolic imbalances between the synthesis and degradation of LDs can result in the accumulation of significant amounts of lipid deposition, a characteristic feature of hepatocytes in patients with fatty liver disease, a leading indication for liver transplant in the United States. In this review, the authors highlight new literature related to the synthesis and autophagic catabolism of LDs, discussing key proteins and machinery involved in these processes. They also discuss recent findings that have revealed novel genetic risk factors associated with LD biology that contribute to lipid retention in the diseased liver.
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Affiliation(s)
- Ryan J. Schulze
- Department of Biochemistry and Molecular Biology and the Center for Digestive Diseases, Mayo Clinic, Rochester, Minnesota
| | - Mark A. McNiven
- Department of Biochemistry and Molecular Biology and the Center for Digestive Diseases, Mayo Clinic, Rochester, Minnesota
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Messner CJ, Mauch L, Suter-Dick L. Bile salts regulate CYP7A1 expression and elicit a fibrotic response and abnormal lipid production in 3D liver microtissues. Toxicol In Vitro 2019; 60:261-271. [PMID: 31195089 DOI: 10.1016/j.tiv.2019.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/26/2019] [Accepted: 06/03/2019] [Indexed: 12/13/2022]
Abstract
Disrupted regulation and accumulation of bile salts (BS) in the liver can contribute towards progressive liver damage and fibrosis. Here, we investigated the role of BS in the progression of cholestatic injury and liver fibrosis using 3D scaffold-free multicellular human liver microtissues (MTs) comprising the cell lines HepaRG, THP-1 and hTERT-HSCs. This in vitro model has been shown to recapitulate cellular events leading to fibrosis including hepatocellular injury, inflammation and activation of HSCs, ultimately leading to increased deposition of extracellular matrix (ECM). In order to better differentiate the contribution of individual cells during cholestasis, the effects of BS were evaluated either on each of the three cell types individually or on the multicellular MTs. Our data corroborate the toxic effects of BS on HepaRG cells and indicate that BS exposure elicited a slight increase in cytokines without causing stellate cell activation. Contrarily, using the MTs, we could demonstrate that low concentrations of BS led to cellular damage and triggered a fibrotic response. This indicates that cellular interplay is required to achieve BS-triggered activation of HSC. Moreover, BS were capable of down-regulating CYP7A1 expression in MTs and elicited abnormal lipid production (accumulation) concordant with clinical cases where chronic cholestasis results in hypercholesterolemia.
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Affiliation(s)
- Catherine Jane Messner
- School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland; Department of Pharmaceutical Sciences, University of Basel, 4056 Basel, Switzerland.
| | - Linda Mauch
- School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland
| | - Laura Suter-Dick
- School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland
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Abstract
PURPOSE OF REVIEW Hepatitis C virus (HCV) infection has been the leading cause of cirrhosis in the United States now for the last several decades. With the introduction of highly effective direct acting antiviral (DAA) drugs, cure rates are now almost 100%. With this explosion of effective therapy, it is possible that many patients with HCV may have reversion in fibrosis. The purpose of this review is, therefore, to report on recent findings in this field. RECENT FINDINGS Older data that examined the effect of interferon-based HCV therapy indicate that fibrosis reverses after HCV eradication. More recent work in the DAA era similarly indicates that fibrosis is reversible. A caveat is that DAA therapy causes rapid viral clearance, and appears to lead to rapid reductions in inflammation. Some tools (such as transient elastography), which may also reflect the inflammatory response, and thus may 'overestimate' of fibrosis reversal. However, emerging data suggesting improved outcomes in patients with cirrhosis after HCV clearance support the concept that even cirrhosis reverses in some patients. SUMMARY Fibrosis (and cirrhosis) reversion, to some extent, occurs after HCV clearance. This topic is vitally important and information continues to emerge; more data on this subject are expected and needed.
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Bobowski-Gerard M, Zummo FP, Staels B, Lefebvre P, Eeckhoute J. Retinoids Issued from Hepatic Stellate Cell Lipid Droplet Loss as Potential Signaling Molecules Orchestrating a Multicellular Liver Injury Response. Cells 2018; 7:cells7090137. [PMID: 30217095 PMCID: PMC6162435 DOI: 10.3390/cells7090137] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 09/11/2018] [Accepted: 09/13/2018] [Indexed: 02/08/2023] Open
Abstract
Hepatic stellate cells (HSCs) serve as the main body storage compartment for vitamin A through retinyl ester (RE)-filled lipid droplets (LDs). Upon liver injury, HSCs adopt a myofibroblastic phenotype characterized by an elevated expression of extracellular matrix proteins and a concomitant loss of LDs. On the one hand, LD breakdown has been suggested to provide the energy required for HSC activation into myofibroblast-like cells. On the other hand, this process could mitigate HSC activation following the transformation of released REs into retinoic acids (RAs), ligands for nuclear receptors exerting antifibrotic transcriptional regulatory activities in HSCs. Importantly, RAs may also constitute a means for HSCs to orchestrate the liver response to injury by triggering transcriptional effects in multiple additional surrounding liver cell populations. We envision that new approaches, such as single-cell technologies, will allow to better define how RAs are issued from LD loss in HSCs exert a multicellular control of the liver (patho)physiology.
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Affiliation(s)
- Marie Bobowski-Gerard
- Institut Pasteur de Lille, The University of Lille, Inserm, CHU Lille, U1011-EGID, F-59000 Lille, France.
| | - Francesco Paolo Zummo
- Institut Pasteur de Lille, The University of Lille, Inserm, CHU Lille, U1011-EGID, F-59000 Lille, France.
| | - Bart Staels
- Institut Pasteur de Lille, The University of Lille, Inserm, CHU Lille, U1011-EGID, F-59000 Lille, France.
| | - Philippe Lefebvre
- Institut Pasteur de Lille, The University of Lille, Inserm, CHU Lille, U1011-EGID, F-59000 Lille, France.
| | - Jérôme Eeckhoute
- Institut Pasteur de Lille, The University of Lille, Inserm, CHU Lille, U1011-EGID, F-59000 Lille, France.
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