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Staršíchová A. SR-B1-/-ApoE-R61h/h Mice Mimic Human Coronary Heart Disease. Cardiovasc Drugs Ther 2023:10.1007/s10557-023-07475-8. [PMID: 37273155 DOI: 10.1007/s10557-023-07475-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/22/2023] [Indexed: 06/06/2023]
Abstract
Cardiovascular diseases are the leading cause of death in the modern world. Atherosclerosis underlies the majority of these pathologies and may result in sudden life-threatening events such as myocardial infarction or stroke. Current concepts consider a rupture (resp. erosion) of "unstable/vulnerable" atherosclerotic plaques as a primary cause leading to thrombus formation and subsequent occlusion of the artery lumen finally triggering an acute clinical event. We and others described SR-B1-/-ApoE-R61h/h mice mimicking clinical coronary heart disease in all major aspects: from coronary atherosclerosis through vulnerable plaque ruptures leading to thrombus formation/coronary artery occlusion, finally resulting in myocardial infarction/ischemia. SR-B1-/-ApoE-R61h/h mouse provides a valuable model to study vulnerable/occlusive plaques, to evaluate bioactive compounds as well as new anti-inflammatory and "anti-rupture" drugs, and to test new technologies in experimental cardiovascular medicine. This review summarizes and discuss our knowledge about SR-B1-/-ApoE-R61h/h mouse model based on recent publications and experimental observations from the lab.
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Affiliation(s)
- Andrea Staršíchová
- Graduate School Cell Dynamics and Disease, University of Muenster, Muenster, Germany.
- European Institute for Molecular Imaging, University of Muenster, Muenster, Germany.
- Novogenia Covid GmbH, Eugendorf, Austria.
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2
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Fuller MT, Dadoo O, Xiong T, Chivukula P, MacDonald ME, Lee SK, Austin RC, Igdoura SA, Trigatti BL. Extensive diet-induced atherosclerosis in scavenger receptor class B type 1-deficient mice is associated with substantial leukocytosis and elevated vascular cell adhesion molecule-1 expression in coronary artery endothelium. Front Physiol 2023; 13:1023397. [PMID: 36714321 PMCID: PMC9877335 DOI: 10.3389/fphys.2022.1023397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 12/21/2022] [Indexed: 01/14/2023] Open
Abstract
High levels of low density lipoprotein (LDL) cholesterol and low levels of high density lipoprotein (HDL) cholesterol are risk factors for cardiovascular disease. Mice that lack genes involved in the clearance of LDL from the bloodstream, such as the LDL receptor and apolipoprotein E, are widely used models of experimental atherosclerosis. Conversely, mice that lack the HDL receptor, scavenger receptor class B type I, and therefore have disrupted HDL functionality, also develop diet-inducible atherosclerosis but are a seldom-used disease model. In this study, we compared atherosclerosis and associated phenotypes in scavenger receptor class B type I knockout mice with those of wild type, LDL receptor knockout, and apolipoprotein E knockout mice after 20 weeks of being fed an atherogenic diet containing sodium cholate. We found that while scavenger receptor class B type I knockout mice had substantially lower plasma cholesterol than LDL receptor and apolipoprotein E knockout mice, they developed atherosclerotic plaques with similar sizes and compositions in their aortic sinuses, and more extensive atherosclerosis in their descending aortas and coronary arteries. This was associated with elevated tumor necrosis factor alpha levels in scavenger receptor class B type I knockout mice compared to wild type and LDL receptor knockout mice, and lymphocytosis, monocytosis, and elevated vascular cell adhesion molecule expression in coronary artery endothelial cells compared to the other mice examined. We conclude that extensive atherosclerosis in arteries that are not generally susceptible to atherosclerosis in scavenger receptor class B type I knockout mice is driven by factors in addition to hypercholesterolemia, including inflammation, dysregulation of the immune system and increased sensitivity of endothelial cells in arteries that are normally resistant to atherosclerosis. Scavenger receptor class B type I knockout mice fed a cholate containing atherogenic diet may prove to be a useful model to study mechanisms of atherosclerosis and evaluate treatments that rely on intact LDL clearance pathways.
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Affiliation(s)
- Mark T. Fuller
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Omid Dadoo
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Ting Xiong
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Pardh Chivukula
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Melissa E. MacDonald
- Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Samuel K. Lee
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada
| | - Richard C. Austin
- Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada,Department of Medicine, Division of Nephrology, The Research Institute of St. Joe’s Hamilton and the Hamilton Center for Kidney Research, McMaster University, Hamilton, ON, Canada
| | - Suleiman A. Igdoura
- Department of Biology and Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Bernardo L. Trigatti
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada,Thrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada,*Correspondence: Bernardo L. Trigatti,
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3
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Wu CH, Guo L, Hao D, Wang Q, Ye X, Ito M, Huang B, Mineo C, Shaul PW, Li XA. Relative adrenal insufficiency is a risk factor and endotype of sepsis - A proof-of-concept study to support a precision medicine approach to guide glucocorticoid therapy for sepsis. Front Immunol 2023; 13:1110516. [PMID: 36713379 PMCID: PMC9878847 DOI: 10.3389/fimmu.2022.1110516] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/28/2022] [Indexed: 01/13/2023] Open
Abstract
Introduction 25-60% of septic patients experience relative adrenal insufficiency (RAI) and glucocorticoid (GC) is frequently used in septic patients. However, the efficacy of GC therapy and whether GC therapy should be based on the status of RAI are highly controversial. Our poor understanding about the pathogenesis of RAI and a lack of RAI animal model present significant barriers to address these critical issues. Methods Scavenger receptor BI (SR-BI) regulates stress-induced GC (iGC) production in response to stress. We generated SF1CreSR-BIfl/fl mice and utilized the mice as a RAI model to elucidate the pathogenesis of RAI and GC therapy in sepsis. SF1CreSR-BIfl/fl mice did not express SR-BI in adrenal gland and lacked iGC production upon ACTH stimulation, thus, they are RAI. Results and Discussion RAI mice were susceptible to cecal ligation and puncture (CLP)-induced sepsis (6.7% survival in SF1CreSR-BIfl/fl mice versus 86.4% in SR-BIfl/fl mice; p = 0.0001). Compared to a well-controlled systemic inflammatory response in SR-BIfl/fl mice, SF1CreSR-BIfl/fl mice featured a persistent hyperinflammatory response. Supplementation of a low stress dose of GC to SF1CreSR-BIfl/fl mice kept the inflammatory response under control and rescued the mice. However, SR-BIfl/fl mice receiving GC treatment exhibited significantly less survival compared to SR-BIfl/fl mice without GC treatment. In conclusions, we demonstrated that RAI is a risk factor for death in this mouse model of sepsis. We further demonstrated that RAI is an endotype of sepsis, which features persistent hyperinflammatory response. We found that GC treatment benefits mice with RAI but harms mice without RAI. Our study provides a proof of concept to support a precision medicine approach for sepsis therapy - selectively applying GC therapy for a subgroup of patients with RAI.
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Affiliation(s)
- Chia-Hua Wu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Ling Guo
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Dan Hao
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Qian Wang
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Xiang Ye
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Misa Ito
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Bin Huang
- Division of Cancer Biostatistics, Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Chieko Mineo
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Philip W. Shaul
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Xiang-An Li
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, KY, United States
- Lexington Veterans Affairs (VA), Healthcare System, Lexington, KY, United States
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, United States
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4
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Paterson HAB, Yu S, Artigas N, Prado MA, Haberman N, Wang YF, Jobbins AM, Pahita E, Mokochinski J, Hall Z, Guerin M, Paulo JA, Ng SS, Villarroya F, Rashid ST, Le Goff W, Lenhard B, Cebola I, Finley D, Gygi SP, Sibley CR, Vernia S. Liver RBFOX2 regulates cholesterol homeostasis via Scarb1 alternative splicing in mice. Nat Metab 2022; 4:1812-1829. [PMID: 36536133 PMCID: PMC9771820 DOI: 10.1038/s42255-022-00681-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 10/10/2022] [Indexed: 12/24/2022]
Abstract
RNA alternative splicing (AS) expands the regulatory potential of eukaryotic genomes. The mechanisms regulating liver-specific AS profiles and their contribution to liver function are poorly understood. Here, we identify a key role for the splicing factor RNA-binding Fox protein 2 (RBFOX2) in maintaining cholesterol homeostasis in a lipogenic environment in the liver. Using enhanced individual-nucleotide-resolution ultra-violet cross-linking and immunoprecipitation, we identify physiologically relevant targets of RBFOX2 in mouse liver, including the scavenger receptor class B type I (Scarb1). RBFOX2 function is decreased in the liver in diet-induced obesity, causing a Scarb1 isoform switch and alteration of hepatocyte lipid homeostasis. Our findings demonstrate that specific AS programmes actively maintain liver physiology, and underlie the lipotoxic effects of obesogenic diets when dysregulated. Splice-switching oligonucleotides targeting this network alleviate obesity-induced inflammation in the liver and promote an anti-atherogenic lipoprotein profile in the blood, underscoring the potential of isoform-specific RNA therapeutics for treating metabolism-associated diseases.
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Affiliation(s)
- Helen A B Paterson
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Sijia Yu
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Natalia Artigas
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Miguel A Prado
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Instituto de Investigación Sanitaria del Principado de Asturias, Avenida Hospital Universitario, Oviedo, Spain
| | - Nejc Haberman
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Yi-Fang Wang
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Andrew M Jobbins
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Elena Pahita
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Joao Mokochinski
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Zoe Hall
- Division of Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Maryse Guerin
- Sorbonne Université, Inserm, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Paris, France
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Soon Seng Ng
- Division of Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Francesc Villarroya
- Biochemistry and Molecular Biomedicine Department, Institute of Biomedicine, University of Barcelona & Research Institute Sant Joan de Déu, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), ISCIII, Madrid, Spain
| | - Sheikh Tamir Rashid
- Division of Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Wilfried Le Goff
- Sorbonne Université, Inserm, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Paris, France
| | - Boris Lenhard
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Inês Cebola
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Daniel Finley
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Christopher R Sibley
- Institute of Quantitative Biology, Biochemistry and Biotechnology. School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Santiago Vernia
- MRC London Institute of Medical Sciences, London, UK.
- Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK.
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5
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Liu Q, Xiao JJ, Wang S, Li Y, Yang LJ, Lu QY, Wu XY, Cao J, Yu H, Zhang BF. Paraoxonase 1 Ameliorates Renal Lipotoxicity by Activating Lipophagy and Inhibiting Pyroptosis. THE AMERICAN JOURNAL OF PATHOLOGY 2022; 192:1531-1545. [PMID: 35963464 DOI: 10.1016/j.ajpath.2022.07.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 07/02/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Several studies in recent years have shown that lipid overload causes lipotoxic damage to the kidney, and oxidative stress, inflammation, and autophagic arrest are all important mechanisms of renal lipotoxicity. However, effective measures with therapeutic effects on renal lipotoxicity are limited. The present study indicated the protective effect of the paraoxonase 1 (PON1) against renal lipotoxicity in high-fat diet-fed scavenger receptor class B type I-deficient (SR-BI-/-) mice. The results showed that SR-BI-/- mice exhibited significant renal pathologic characteristics, such as oxidative stress, inflammation, and fibrosis, under a normal chow diet, and were accompanied by dyslipidemia and reduced plasma PON1 activity and renal PON1 levels. PON1 overexpression significantly attenuated the above pathologic changes in the kidneys of SR-BI-/- mice fed with a high-fat diet. Mechanistically, PON1 may ameliorate renal oxidative stress by reducing reactive oxygen species production, reduce renal lipid accumulation by inhibiting AKT/mechanistic target of rapamycin kinase pathway to activate lipophagy, and reduce the occurrence of inflammation and cell death by inhibiting Nod-like receptor family protein 3 inflammasome-mediated pyroptosis. The present study is the first to show that PON1 overexpression can effectively alleviate renal lipotoxicity injury, and PON1 may be a promising therapeutic strategy for the treatment of renal lipotoxicity-related diseases.
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Affiliation(s)
- Qing Liu
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Jing-Jie Xiao
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Shan Wang
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Ying Li
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Li-Jiao Yang
- Department of Nephrology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qian-Yu Lu
- Department of Nephrology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xiao-Yan Wu
- Department of Nephrology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jia Cao
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Hong Yu
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China.
| | - Bai-Fang Zhang
- Department of Biochemistry and Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University TaiKang Medical School (School of Basic Medical Sciences), Wuhan, China.
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6
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Abstract
PURPOSE OF REVIEW Scavenger receptor class B type 1 (SR-B1) promotes atheroprotection through its role in HDL metabolism and reverse cholesterol transport in the liver. However, evidence indicates that SR-B1 may impact atherosclerosis through nonhepatic mechanisms. RECENT FINDINGS Recent studies have brought to light various mechanisms by which SR-B1 affects lesional macrophage function and protects against atherosclerosis. Efferocytosis is efficient in early atherosclerotic lesions. At this stage, and beyond its role in cholesterol efflux, SR-B1 promotes free cholesterol-induced apoptosis of macrophages through its control of apoptosis inhibitor of macrophage (AIM). At more advanced stages, macrophage SR-B1 binds and mediates the removal of apoptotic cells. SR-B1 also participates in the induction of autophagy which limits necrotic core formation and increases plaque stability. SUMMARY These studies shed new light on the atheroprotective role of SR-B1 by emphasizing its essential contribution in macrophages during atherogenesis as a function of lesion stages. These new findings suggest that macrophage SR-B1 is a therapeutic target in cardiovascular disease.
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Affiliation(s)
- Thierry Huby
- Sorbonne Universités, INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Paris, France
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7
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Abe RJ, Abe JI, Nguyen MTH, Olmsted-Davis EA, Mamun A, Banerjee P, Cooke JP, Fang L, Pownall H, Le NT. Free Cholesterol Bioavailability and Atherosclerosis. Curr Atheroscler Rep 2022; 24:323-336. [PMID: 35332444 PMCID: PMC9050774 DOI: 10.1007/s11883-022-01011-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2022] [Indexed: 11/30/2022]
Abstract
PURPOSE OF REVIEW As both a cholesterol acceptor and carrier in the reverse cholesterol transport (RCT) pathway, high-density lipoprotein (HDL) is putatively atheroprotective. However, current pharmacological therapies to increase plasma HDL cholesterol (HDL-c) concentration have paradoxically failed to prevent or reduce atherosclerosis and cardiovascular disease (CVD). Given that free cholesterol (FC) transfer between surfaces of lipoproteins and cells is reversible, excess plasma FC can be transferred to the cells of peripheral tissue sites resulting in atherosclerosis. Here, we summarize potential mechanisms contributing to this paradox and highlight the role of excess free cholesterol (FC) bioavailability in atherosclerosis vs. atheroprotection. RECENT FINDINGS Recent findings have established a complex relationship between HDL-c concentration and atherosclerosis. Systemic scavenger receptor class B type 1 (SR-B1) knock out (KO) mice exhibit with increased diet-induced atherosclerosis despite having an elevated plasma HDL-c concentration compared to wild type (WT) mice. The greater bioavailability of HDL-FC in SR-B1 vs. WT mice is associated with a higher FC content in multiple cell types and tissue sites. These results suggest that dysfunctional HDL with high FC bioavailability is atheroprone despite high HDL-c concentration. Past oversimplification of HDL-c involvement in cholesterol transport has led to the failures in HDL targeted therapy. Evidence suggests that FC-mediated functionality of HDL is of higher importance than its quantity; as a result, deciphering the regulatory mechanisms by which HDL-FC bioavailability can induce atherosclerosis can have far-reaching clinical implications.
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Affiliation(s)
- Rei J Abe
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
| | - Jun-Ichi Abe
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Minh T H Nguyen
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
- University of Science and Technology of Hanoi, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | | | - Abrar Mamun
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - Priyanka Banerjee
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - John P Cooke
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
- Weill Cornell Medicine, New York, NY, USA
| | - Longhou Fang
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
- Weill Cornell Medicine, New York, NY, USA
| | - Henry Pownall
- Weill Cornell Medicine, New York, NY, USA
- Center for Bioenergetics, Department of Medicine, Houston Methodist Research Institute, Houston, TX, USA
| | - Nhat-Tu Le
- Center for Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA.
- Weill Cornell Medicine, New York, NY, USA.
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8
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Darabi M, Lhomme M, Dahik VD, Guillas I, Frisdal E, Tubeuf E, Poupel L, Patel M, Gautier EL, Huby T, Guerin M, Rye KA, Lesnik P, Le Goff W, Kontush A. Phosphatidylserine enhances anti-inflammatory effects of reconstituted HDL in macrophages via distinct intracellular pathways. FASEB J 2022; 36:e22274. [PMID: 35416331 DOI: 10.1096/fj.201800810r] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 03/01/2022] [Accepted: 03/14/2022] [Indexed: 11/11/2022]
Abstract
Phosphatidylserine (PS) is a minor phospholipid constituent of high-density lipoprotein (HDL) that exhibits potent anti-inflammatory activity. It remains indeterminate whether PS incorporation can enhance anti-inflammatory effects of reconstituted HDL (rHDL). Human macrophages were treated with rHDL containing phosphatidylcholine alone (PC-rHDL) or PC and PS (PC/PS-rHDL). Interleukin (IL)-6 secretion and expression was more strongly inhibited by PC/PS-rHDL than PC-rHDL in both tumor necrosis factor (TNF)-α- and lipopolysaccharide (LPS)-stimulated macrophages. siRNA experiments revealed that the enhanced anti-inflammatory effects of PC/PS-rHDL required scavenger receptor class B type I (SR-BI). Furthermore, PC/PS-rHDL induced a greater increase in Akt1/2/3 phosphorylation than PC-rHDL. In addition, PC/PS but not PC-rHDL decreased the abundance of plasma membrane lipid rafts and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation. Finally, when these rHDL formulations were administered to dyslipidemic low-density lipoprotein (LDL)-receptor knockout mice fed a high-cholesterol diet, circulating IL-6 levels were significantly reduced only in PC/PS-rHDL-treated mice. In parallel, enhanced Akt1/2/3 phosphorylation by PC/PS-rHDL was observed in the mouse aortic tissue using immunohistochemistry. We concluded that the incorporation of PS into rHDLs enhanced their anti-inflammatory activity by modulating Akt1/2/3- and p38 MAPK-mediated signaling through SR-BI in stimulated macrophages. These data identify PS as a potent anti-inflammatory component capable of enhancing therapeutic potential of rHDL-based therapy.
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Affiliation(s)
- Maryam Darabi
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Marie Lhomme
- ICAN Analytics, Lipidomics Core, Foundation for Innovation in Cardiometabolism and Nutrition (IHU-ICAN, ANR-10-IAHU-05), Paris, France
| | - Veronica D Dahik
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Isabelle Guillas
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Eric Frisdal
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Emilie Tubeuf
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Lucie Poupel
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Mili Patel
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Emmanuel L Gautier
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Thierry Huby
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Maryse Guerin
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Kerry-Anne Rye
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Philippe Lesnik
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Wilfried Le Goff
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
| | - Anatol Kontush
- INSERM, Institute of Cardiometabolism and Nutrition (ICAN), UMR_S1166, Sorbonne Université, Paris, France
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9
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Apolipoprotein A1-Related Proteins and Reverse Cholesterol Transport in Antiatherosclerosis Therapy: Recent Progress and Future Perspectives. Cardiovasc Ther 2022; 2022:4610834. [PMID: 35087605 PMCID: PMC8763555 DOI: 10.1155/2022/4610834] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 09/30/2021] [Accepted: 12/10/2021] [Indexed: 12/12/2022] Open
Abstract
Hyperlipidemia characterized by abnormal deposition of cholesterol in arteries can cause atherosclerosis and coronary artery occlusion, leading to atherosclerotic coronary heart disease. The body prevents atherosclerosis by reverse cholesterol transport to mobilize and excrete cholesterol and other lipids. Apolipoprotein A1, the major component of high-density lipoprotein, plays a key role in reverse cholesterol transport. Here, we reviewed the role of apolipoprotein A1-targeting molecules in antiatherosclerosis therapy, in particular ATP-binding cassette transporter A1, lecithin-cholesterol acyltransferase, and scavenger receptor class B type 1.
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10
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Rozhkova AV, Dmitrieva VG, Nosova EV, Dergunov AD, Limborska SA, Dergunova LV. Genomic Variants and Multilevel Regulation of ABCA1, ABCG1, and SCARB1 Expression in Atherogenesis. J Cardiovasc Dev Dis 2021; 8:jcdd8120170. [PMID: 34940525 PMCID: PMC8707585 DOI: 10.3390/jcdd8120170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 12/12/2022] Open
Abstract
Atheroprotective properties of human plasma high-density lipoproteins (HDLs) are determined by their involvement in reverse cholesterol transport (RCT) from the macrophage to the liver. ABCA1, ABCG1, and SR-BI cholesterol transporters are involved in cholesterol efflux from macrophages to lipid-free ApoA-I and HDL as a first RCT step. Molecular determinants of RCT efficiency that may possess diagnostic and therapeutic meaning remain largely unknown. This review summarizes the progress in studying the genomic variants of ABCA1, ABCG1, and SCARB1, and the regulation of their function at transcriptional and post-transcriptional levels in atherosclerosis. Defects in the structure and function of ABCA1, ABCG1, and SR-BI are caused by changes in the gene sequence, such as single nucleotide polymorphism or various mutations. In the transcription initiation of transporter genes, in addition to transcription factors, long noncoding RNA (lncRNA), transcription activators, and repressors are also involved. Furthermore, transcription is substantially influenced by the methylation of gene promoter regions. Post-transcriptional regulation involves microRNAs and lncRNAs, including circular RNAs. The potential biomarkers and targets for atheroprotection, based on molecular mechanisms of expression regulation for three transporter genes, are also discussed in this review.
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Affiliation(s)
- Alexandra V. Rozhkova
- Department of Molecular Bases of Human Genetics, Institute of Molecular Genetics of National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (A.V.R.); (V.G.D.); (E.V.N.); (S.A.L.); (L.V.D.)
| | - Veronika G. Dmitrieva
- Department of Molecular Bases of Human Genetics, Institute of Molecular Genetics of National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (A.V.R.); (V.G.D.); (E.V.N.); (S.A.L.); (L.V.D.)
| | - Elena V. Nosova
- Department of Molecular Bases of Human Genetics, Institute of Molecular Genetics of National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (A.V.R.); (V.G.D.); (E.V.N.); (S.A.L.); (L.V.D.)
| | - Alexander D. Dergunov
- Laboratory of Structural Fundamentals of Lipoprotein Metabolism, National Medical Research Center for Therapy and Preventive Medicine, 101990 Moscow, Russia
- Correspondence:
| | - Svetlana A. Limborska
- Department of Molecular Bases of Human Genetics, Institute of Molecular Genetics of National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (A.V.R.); (V.G.D.); (E.V.N.); (S.A.L.); (L.V.D.)
| | - Liudmila V. Dergunova
- Department of Molecular Bases of Human Genetics, Institute of Molecular Genetics of National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (A.V.R.); (V.G.D.); (E.V.N.); (S.A.L.); (L.V.D.)
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11
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Gracia-Rubio I, Martín C, Civeira F, Cenarro A. SR-B1, a Key Receptor Involved in the Progression of Cardiovascular Disease: A Perspective from Mice and Human Genetic Studies. Biomedicines 2021; 9:biomedicines9060612. [PMID: 34072125 PMCID: PMC8229968 DOI: 10.3390/biomedicines9060612] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 12/21/2022] Open
Abstract
High plasma level of low-density lipoprotein (LDL) is the main driver of the initiation and progression of cardiovascular disease (CVD). Nevertheless, high-density lipoprotein (HDL) is considered an anti-atherogenic lipoprotein due to its role in reverse cholesterol transport and its ability to receive cholesterol that effluxes from macrophages in the artery wall. The scavenger receptor B class type 1 (SR-B1) was identified as the high-affinity HDL receptor, which facilitates the selective uptake of cholesterol ester (CE) into the liver via HDL and is also implicated in the plasma clearance of LDL, very low-density lipoprotein (VLDL) and lipoprotein(a) (Lp(a)). Thus, SR-B1 is a multifunctional receptor that plays a main role in the metabolism of different lipoproteins. The aim of this review is to highlight the association between SR-B1 and CVD risk through mice and human genetic studies.
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Affiliation(s)
- Irene Gracia-Rubio
- Unidad Clínica y de Investigación en Lípidos y Arteriosclerosis, Instituto de Investigación Sanitaria Aragón (IIS Aragón), Hospital Universitario Miguel Servet, 50009 Zaragoza, Spain; (F.C.); (A.C.)
- Correspondence: or ; Tel.: +34-976-765-500 (ext. 142895)
| | - César Martín
- Instituto Biofisika (UPV/EHU, CSIC) y Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco UPB/EHU, 48940 Bilbao, Spain;
| | - Fernando Civeira
- Unidad Clínica y de Investigación en Lípidos y Arteriosclerosis, Instituto de Investigación Sanitaria Aragón (IIS Aragón), Hospital Universitario Miguel Servet, 50009 Zaragoza, Spain; (F.C.); (A.C.)
- Centro de Investigación Biomédica en Red Cardiovascular (CIBERCV), Instituto Salud Carlos III, 28029 Madrid, Spain
- Departamento de Medicina, Psiquiatría y Dermatología, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Ana Cenarro
- Unidad Clínica y de Investigación en Lípidos y Arteriosclerosis, Instituto de Investigación Sanitaria Aragón (IIS Aragón), Hospital Universitario Miguel Servet, 50009 Zaragoza, Spain; (F.C.); (A.C.)
- Centro de Investigación Biomédica en Red Cardiovascular (CIBERCV), Instituto Salud Carlos III, 28029 Madrid, Spain
- Instituto Aragonés de Ciencias de la Salud (IACS), 50009 Zaragoza, Spain
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12
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Hou X, Zhang C, Wang L, Wang K. Natural Piperine Improves Lipid Metabolic Profile of High-Fat Diet-Fed Mice by Upregulating SR-B1 and ABCG8 Transporters. JOURNAL OF NATURAL PRODUCTS 2021; 84:373-381. [PMID: 33492139 DOI: 10.1021/acs.jnatprod.0c01018] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Natural piperine from black pepper is known to function as hypocholesterolemic agent, but how it lowers the blood cholesterol remains unclear. In this study, we found that intragastric administrations of piperine (25 mg/kg/day) for 8 weeks significantly reduced the plasma triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) in high-fat diet (HFD)-fed mice. H&E staining indicated that piperine significantly decreased hepatic lipid accumulation compared with the control group. The Oil Red O staining further showed that piperine attenuated lipid deposition in liver HepG2 cells in a concentration-dependent manner. Mechanistically, piperine treatment caused a significant upregulation of hepatic scavenger receptor B1 (SR-B1) in the liver and transporter protein of ATP binding cassette SGM8 (ABCG8) in the small intestine. Taken together, our findings demonstrate the role of natural piperine in improving lipid metabolic profile that is involved in the reverse cholesterol transport (RCT)-mediated mechanism through upregulation of SR-B1 in the liver and ABCG8 in the small intestine.
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Affiliation(s)
- Xingming Hou
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao 266071, China
| | - Congxiao Zhang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao 266071, China
| | - Limei Wang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao 266071, China
| | - KeWei Wang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao 266071, China
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13
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Mineo C. Lipoprotein receptor signalling in atherosclerosis. Cardiovasc Res 2021; 116:1254-1274. [PMID: 31834409 DOI: 10.1093/cvr/cvz338] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/01/2019] [Accepted: 12/10/2019] [Indexed: 12/11/2022] Open
Abstract
The founding member of the lipoprotein receptor family, low-density lipoprotein receptor (LDLR) plays a major role in the atherogenesis through the receptor-mediated endocytosis of LDL particles and regulation of cholesterol homeostasis. Since the discovery of the LDLR, many other structurally and functionally related receptors have been identified, which include low-density lipoprotein receptor-related protein (LRP)1, LRP5, LRP6, very low-density lipoprotein receptor, and apolipoprotein E receptor 2. The scavenger receptor family members, on the other hand, constitute a family of pattern recognition proteins that are structurally diverse and recognize a wide array of ligands, including oxidized LDL. Among these are cluster of differentiation 36, scavenger receptor class B type I and lectin-like oxidized low-density lipoprotein receptor-1. In addition to the initially assigned role as a mediator of the uptake of macromolecules into the cell, a large number of studies in cultured cells and in in vivo animal models have revealed that these lipoprotein receptors participate in signal transduction to modulate cellular functions. This review highlights the signalling pathways by which these receptors influence the process of atherosclerosis development, focusing on their roles in the vascular cells, such as macrophages, endothelial cells, smooth muscle cells, and platelets. Human genetics of the receptors is also discussed to further provide the relevance to cardiovascular disease risks in humans. Further knowledge of the vascular biology of the lipoprotein receptors and their ligands will potentially enhance our ability to harness the mechanism to develop novel prophylactic and therapeutic strategies against cardiovascular diseases.
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Affiliation(s)
- Chieko Mineo
- Department of Pediatrics and Cell Biology, Center for Pulmonary and Vascular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9063, USA
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14
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Yu L, Dai Y, Mineo C. Novel Functions of Endothelial Scavenger Receptor Class B Type I. Curr Atheroscler Rep 2021; 23:6. [PMID: 33420646 DOI: 10.1007/s11883-020-00903-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2020] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Scavenger receptor class B type I (SR-BI) serves a key role in the reverse cholesterol transport in the liver as the high-affinity receptor for HDL. SR-BI is abundantly expressed in endothelium, and earlier works indicate that the receptor mediates anti-atherogenic actions of HDL. However, more recent studies uncovered novel functions of endothelial SR-BI as a lipoprotein transporter, which regulates transcellular transport process of both LDL and HDL. This brief review focuses on the unique functions of endothelial SR-BI and how they influence atherogenesis. RECENT FINDINGS Earlier studies indicate that SR-BI facilitates anti-atherogenic actions of HDL through modulation of intracellular signaling to stimulate endothelial nitric oxide synthase. In vivo studies in global SR-BI knockout mice also showed a strong atheroprotective role of the receptor; however, a contribution of endothelial SR-BI to atherosclerosis process in vivo has not been fully appreciated. Recent studies using cultured endothelial cells and in mice with endothelial-specific deletion of the receptor revealed previously unappreciated pro-atherogenic actions of SR-BI, which relates to its ability to deliver LDL into arteries. On the other hand, SR-BI has also been implicated in transport of HDL to the sub-intimal space as a part of reverse cholesterol transport. SR-BI mediates internalization and transcellular transport of both HDL and LDL, and the cellular and molecular mechanism of the process has just begun to emerge. Harnessing these dual transport functions of the endothelial SR-BI may provide a novel, effective intervention to atherosclerosis.
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Affiliation(s)
- Liming Yu
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Yao Dai
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Chieko Mineo
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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15
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Xu Y, Li Y, Jadhav K, Pan X, Zhu Y, Hu S, Chen S, Chen L, Tang Y, Wang HH, Yang L, Wang DQH, Yin L, Zhang Y. Hepatocyte ATF3 protects against atherosclerosis by regulating HDL and bile acid metabolism. Nat Metab 2021; 3:59-74. [PMID: 33462514 PMCID: PMC7856821 DOI: 10.1038/s42255-020-00331-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 12/09/2020] [Indexed: 12/13/2022]
Abstract
Activating transcription factor (ATF)3 is known to have an anti-inflammatory function, yet the role of hepatic ATF3 in lipoprotein metabolism or atherosclerosis remains unknown. Here we show that overexpression of human ATF3 in hepatocytes reduces the development of atherosclerosis in Western-diet-fed Ldlr-/- or Apoe-/- mice, whereas hepatocyte-specific ablation of Atf3 has the opposite effect. We further show that hepatic ATF3 expression is inhibited by hydrocortisone. Mechanistically, hepatocyte ATF3 enhances high-density lipoprotein (HDL) uptake, inhibits intestinal fat and cholesterol absorption and promotes macrophage reverse cholesterol transport by inducing scavenger receptor group B type 1 (SR-BI) and repressing cholesterol 12α-hydroxylase (CYP8B1) in the liver through its interaction with p53 and hepatocyte nuclear factor 4α, respectively. Our data demonstrate that hepatocyte ATF3 is a key regulator of HDL and bile acid metabolism and atherosclerosis.
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Affiliation(s)
- Yanyong Xu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Yuanyuan Li
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Zhongshan Institute for Drug Discovery, the Institutes of Drug Discovery and Development, Chinese Academy of Sciences, Zhongshan, China
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Kavita Jadhav
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Xiaoli Pan
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yingdong Zhu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Shuwei Hu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Shaoru Chen
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Liuying Chen
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yong Tang
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Helen H Wang
- Department of Medicine and Genetics, Marion Bessin Liver Research Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ling Yang
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - David Q-H Wang
- Department of Medicine and Genetics, Marion Bessin Liver Research Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Liya Yin
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Yanqiao Zhang
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA.
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16
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High-Density Lipoprotein Therapy in Stroke: Evaluation of Endothelial SR-BI-Dependent Neuroprotective Effects. Int J Mol Sci 2020; 22:ijms22010106. [PMID: 33374266 PMCID: PMC7796353 DOI: 10.3390/ijms22010106] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 02/07/2023] Open
Abstract
High-density lipoproteins (HDLs) display endothelial protective effects. We tested the role of SR-BI, an HDL receptor expressed by endothelial cells, in the neuroprotective effects of HDLs using an experimental model of acute ischemic stroke. After transient intraluminal middle cerebral artery occlusion (tMCAO), control and endothelial SR-BI deficient mice were intravenously injected by HDLs or saline. Infarct volume and blood-brain barrier (BBB) breakdown were assessed 24 h post tMCAO. The potential of HDLs and the role of SR-BI to maintain the BBB integrity was assessed by using a human cellular model of BBB (hCMEC/D3 cell line) subjected to oxygen-glucose deprivation (OGD). HDL therapy limited the infarct volume and the BBB leakage in control mice relative to saline injection. Interestingly, these neuroprotective effects were thwarted by the deletion of SR-BI in endothelial cells and preserved in mice deficient for SR-BI in myeloid cells. In vitro studies revealed that HDLs can preserve the integrity of the BBB in OGD conditions, and that this effect was reduced by the SR-BI inhibitor, BLT-1. The protection of BBB integrity plays a pivotal role in HDL therapy of acute ischemic stroke. Our results show that this effect is partially mediated by the HDL receptor, SR-BI expressed by endothelial cells.
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17
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Galle-Treger L, Moreau M, Ballaire R, Poupel L, Huby T, Sasso E, Troise F, Poti F, Lesnik P, Le Goff W, Gautier EL, Huby T. Targeted invalidation of SR-B1 in macrophages reduces macrophage apoptosis and accelerates atherosclerosis. Cardiovasc Res 2020; 116:554-565. [PMID: 31119270 DOI: 10.1093/cvr/cvz138] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 01/30/2019] [Accepted: 05/16/2019] [Indexed: 12/15/2022] Open
Abstract
AIMS SR-B1 is a cholesterol transporter that exerts anti-atherogenic properties in liver and peripheral tissues in mice. Bone marrow (BM) transfer studies suggested an atheroprotective role in cells of haematopoietic origin. Here, we addressed the specific contribution of SR-B1 in the monocyte/macrophage. METHODS AND RESULTS We generated mice deficient for SR-B1 in monocytes/macrophages (Lysm-Cre × SR-B1f/f) and transplanted their BM into Ldlr-/- mice. Fed a cholesterol-rich diet, these mice displayed accelerated aortic atherosclerosis characterized by larger macrophage-rich areas and decreased macrophage apoptosis compared with SR-B1f/f transplanted controls. These findings were reproduced in BM transfer studies using another atherogenic mouse recipient (SR-B1 KOliver × Cholesteryl Ester Transfer Protein). Haematopoietic reconstitution with SR-B1-/- BM conducted in parallel generated similar results to those obtained with Lysm-Cre × SR-B1f/f BM; thus suggesting that among haematopoietic-derived cells, SR-B1 exerts its atheroprotective role primarily in monocytes/macrophages. Consistent with our in vivo data, free cholesterol (FC)-induced apoptosis of macrophages was diminished in the absence of SR-B1. This effect could not be attributed to differential cellular cholesterol loading. However, we observed that expression of apoptosis inhibitor of macrophage (AIM) was induced in SR-B1-deficient macrophages, and notably upon FC-loading. Furthermore, we demonstrated that macrophages were protected from FC-induced apoptosis by AIM. Finally, AIM protein was found more present within the macrophage-rich area of the atherosclerotic lesions of SR-B1-deficient macrophages than controls. CONCLUSION Our findings suggest that macrophage SR-B1 plays a role in plaque growth by controlling macrophage apoptosis in an AIM-dependent manner.
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Affiliation(s)
| | - Martine Moreau
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | | | - Lucie Poupel
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Thomas Huby
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Emanuele Sasso
- Ceinge Biotecnologie Avanzate S.C.R.L, Via Gaetano Salvatore 486, 80145, Napoli, Italy.,Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, 80131, Napoli, Italy
| | - Fulvia Troise
- Ceinge Biotecnologie Avanzate S.C.R.L, Via Gaetano Salvatore 486, 80145, Napoli, Italy
| | - Francesco Poti
- Department of Medicine and Surgery, Unit of Neurosciences, University of Parma, Parma, Italy
| | - Philippe Lesnik
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Wilfried Le Goff
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | | | - Thierry Huby
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
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18
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Vishnyakova TG, Bocharov AV, Baranova IN, Kurlander R, Drake SK, Chen Z, Amar M, Sviridov D, Vaisman B, Poliakov E, Remaley AT, Eggerman TL, Patterson AP. SR-BI mediates neutral lipid sorting from LDL to lipid droplets and facilitates their formation. PLoS One 2020; 15:e0240659. [PMID: 33057430 PMCID: PMC7561250 DOI: 10.1371/journal.pone.0240659] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 09/30/2020] [Indexed: 12/30/2022] Open
Abstract
SR-BI binds various lipoproteins, including HDL, LDL as well as VLDL, and mediates selective cholesteryl ester (CE) uptake. HDL derived CE accumulates in cellular lipid droplets (LDs), which also store triacylglycerol (TAG). We hypothesized that SR-BI could significantly facilitate LD formation, in part, by directly transporting LDL derived neutral lipids (NL) such as CE and TAG into LDs without lipolysis and de novo lipid synthesis. SR-BI overexpression greatly increased LDL uptake and LD formation in stably transfected HeLa cells (SR-BI-HeLa). LDs isolated from SR-BI-HeLa contained 4- and 7-times more CE and TAG, respectively, than mock-transfected HeLa (Mock-HeLa). In contrast, LDL receptor overexpression in HeLa (LDLr-HeLa) greatly increased LDL uptake, degradation with moderate 1.5- and 2-fold increases of CE and TAG, respectively. Utilizing CE and TAG analogs, BODIPY-TAG (BP-TAG) and BODIPY-CE (BP-CE), for tracking LDL NL, we found that after initial binding of LDL to SR-BI-HeLa, apoB remained at the cell surface, while BP-CE and BP-TAG were sorted and simultaneously transported together to LDs. Both lipids demonstrated limited internalization to lysosomes or endoplasmic reticulum in SR-BI-HeLa. In LDLr-HeLa, NLs demonstrated clear lysosomal sequestration without their sorting to LDs. An inhibition of TAG and CE de novo synthesis by 90-95% only reduced TAG and CE LD content by 45-50%, and had little effect on BP-CE and BP-TAG transport to LDs in SR-BI HeLa. Furthermore, intravenous infusion of 1-2 mg of LDL increased liver LDs in normal (WT) but not in SR-BI KO mice. Mice transgenic for human SR-BI demonstrated higher liver LD accumulation than WT mice. Finally, Electro Spray Infusion Mass Spectrometry (ESI-MS) using deuterated d-CE found that LDs accumulated up to 40% of unmodified d-CE LDL. We conclude that SR-BI mediates LDL-induced LD formation in vitro and in vivo. In addition to cytosolic NL hydrolysis and de novo lipid synthesis, this process includes selective sorting and transport of LDL NL to LDs with limited lysosomal NL sequestration and the transport of LDL CE, and TAG directly to LDs independently of de novo synthesis.
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Affiliation(s)
- Tatyana G. Vishnyakova
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
| | - Alexander V. Bocharov
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
- * E-mail:
| | - Irina N. Baranova
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
| | - Roger Kurlander
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
| | - Steven K. Drake
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
| | - Zhigang Chen
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
| | - Marcelo Amar
- National Heart, Lung and Blood Institute, Bethesda, Maryland, United
States of America
| | - Denis Sviridov
- National Heart, Lung and Blood Institute, Bethesda, Maryland, United
States of America
| | - Boris Vaisman
- National Heart, Lung and Blood Institute, Bethesda, Maryland, United
States of America
| | - Eugenia Poliakov
- National Eye Institute, Bethesda, Maryland, United States of
America
| | - Alan T. Remaley
- National Heart, Lung and Blood Institute, Bethesda, Maryland, United
States of America
| | - Thomas L. Eggerman
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
- National Institute of Diabetes, Digestive and Kidney Diseases, Bethesda,
Maryland, United States of America
| | - Amy P. Patterson
- Clinical Center, The National Institutes of Health, Bethesda, Maryland,
United States of America
- National Heart, Lung and Blood Institute, Bethesda, Maryland, United
States of America
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19
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Molecular determinants of SR-B1-dependent Plasmodium sporozoite entry into hepatocytes. Sci Rep 2020; 10:13509. [PMID: 32782257 PMCID: PMC7419504 DOI: 10.1038/s41598-020-70468-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 07/13/2020] [Indexed: 01/13/2023] Open
Abstract
Sporozoite forms of the Plasmodium parasite, the causative agent of malaria, are transmitted by mosquitoes and first infect the liver for an initial round of replication before parasite proliferation in the blood. The molecular mechanisms involved during sporozoite invasion of hepatocytes remain poorly understood. Two receptors of the Hepatitis C virus (HCV), the tetraspanin CD81 and the scavenger receptor class B type 1 (SR-B1), play an important role during the entry of Plasmodium sporozoites into hepatocytes. In contrast to HCV entry, which requires both CD81 and SR-B1 together with additional host factors, CD81 and SR-B1 operate independently during malaria liver infection. Sporozoites from human-infecting P. falciparum and P. vivax rely respectively on CD81 or SR-B1. Rodent-infecting P. berghei can use SR-B1 to infect host cells as an alternative pathway to CD81, providing a tractable model to investigate the role of SR-B1 during Plasmodium liver infection. Here we show that mouse SR-B1 is less functional as compared to human SR-B1 during P. berghei infection. We took advantage of this functional difference to investigate the structural determinants of SR-B1 required for infection. Using a structure-guided strategy and chimeric mouse/human SR-B1 constructs, we could map the functional region of human SR-B1 within apical loops, suggesting that this region of the protein may play a crucial role for interaction of sporozoite ligands with host cells and thus the very first step of Plasmodium infection.
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20
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Ma B, Jia J, Wang X, Zhang R, Niu S, Ni L, Di X, Liu C. Differential roles of Scavenger receptor class B type I: A protective molecule and a facilitator of atherosclerosis (Review). Mol Med Rep 2020; 22:2599-2604. [PMID: 32945418 PMCID: PMC7453654 DOI: 10.3892/mmr.2020.11383] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/03/2020] [Indexed: 12/12/2022] Open
Abstract
The scavenger receptor class B type I (SR-BI) is a multi-ligand membrane protein receptor that binds to high-density lipoprotein (HDL) under physiological conditions, promoting the selective uptake of cholesterol esters from HDL into cells. SR-BI also promotes the reverse transport of excess cholesterol from peripheral tissues to the liver, contributing to the synthesis of bile acids for excretion and the removal of excess cholesterol from the body, thereby lowering the cholesterol load and exerting anti-atherosclerotic effects. Studies in mice and humans have demonstrated that a functional defect of SR-BI can cause atherosclerotic lesions and cardiovascular diseases, such as myocardial infarction and stroke. Additionally, SR-BI in vascular endothelial cells promoted the deposition of low-density lipoprotein under the endothelium. Although SR-BI is widely expressed in various tissues and cell types throughout the body, its expression level and function vary accordingly. The present review focuses on the biological functions and mechanisms of SR-BI in regulating atherosclerosis.
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Affiliation(s)
- Baitao Ma
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Jing Jia
- Department of Obstetrics and Gynaecology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Xuebin Wang
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Rui Zhang
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Shuai Niu
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Leng Ni
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Xiao Di
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
| | - Changwei Liu
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China
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21
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Singh AB, Dong B, Kraemer FB, Liu J. FXR activation promotes intestinal cholesterol excretion and attenuates hyperlipidemia in SR-B1-deficient mice fed a high-fat and high-cholesterol diet. Physiol Rep 2020; 8:e14387. [PMID: 32170842 PMCID: PMC7070099 DOI: 10.14814/phy2.14387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/27/2020] [Accepted: 01/28/2020] [Indexed: 12/14/2022] Open
Abstract
Obeticholic acid (OCA) activates the farnesoid X receptor (FXR) to lower circulating total cholesterol (TC) and high density lipoprotein-cholesterol (HDL-C) concentrations and to stimulate fecal cholesterol excretion in mice by increasing hepatic SR-B1 expression. Here we show that hepatic SR-B1 depletion by an adenovirus expressing Sr-b1 shRNA (Ad-shSR-B1) attenuated these beneficial effects of OCA in mice on a chow diet. The mRNA levels of ABC cholesterol transporter genes (Abca1, Abcg1, Abcg5, and Abcg8) were unchanged in the liver of hepatic SR-B1-depleted mice regardless of OCA treatment; however, a modest increase in Abca1, Abcg5, and Abcg8 mRNA levels was observed in the ileum of vehicle-treated control mice and Abca1 and Abcg8 mRNA levels were increased more by OCA administration. OCA treatment of Sr-b1 knock out (KO) mice (Sr-b1-/-) fed a normal chow diet (NCD) displayed a similar lack of transhepatic cholesterol movement, as well as a modest increase in the levels of ileum cholesterol transporter expression. However, OCA treatment of Sr-b1 KO mice fed a cholesterol-enriched diet reduced circulating cholesterol and increased fecal cholesterol output to comparable degrees to that of wild-type (WT) mice, and these effects were accompanied by substantial elevations of mRNA levels of Abca1, Abcg1, Abcg5, and Abcg8 in the ileum of Sr-b1 KO mice. Our studies suggest that FXR activation stimulates intestinal cholesterol excretion and reduces diet-induced hyperlipidemia through increased expression of ileal cholesterol transporters when hepatic SR-B1-mediated cholesterol movement is absent.
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Affiliation(s)
- Amar B. Singh
- Veterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
| | - Bin Dong
- Veterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
| | - Fredric B. Kraemer
- Veterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
- Department of MedicineStanford University School of MedicineStanfordCAUSA
| | - Jingwen Liu
- Veterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
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22
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Le Roy T, Lécuyer E, Chassaing B, Rhimi M, Lhomme M, Boudebbouze S, Ichou F, Haro Barceló J, Huby T, Guerin M, Giral P, Maguin E, Kapel N, Gérard P, Clément K, Lesnik P. The intestinal microbiota regulates host cholesterol homeostasis. BMC Biol 2019; 17:94. [PMID: 31775890 PMCID: PMC6882370 DOI: 10.1186/s12915-019-0715-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/25/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Management of blood cholesterol is a major focus of efforts to prevent cardiovascular diseases. The objective of this study was to investigate how the gut microbiota affects host cholesterol homeostasis at the organism scale. RESULTS We depleted the intestinal microbiota of hypercholesterolemic female Apoe-/- mice using broad-spectrum antibiotics. Measurement of plasma cholesterol levels as well as cholesterol synthesis and fluxes by complementary approaches showed that the intestinal microbiota strongly regulates plasma cholesterol level, hepatic cholesterol synthesis, and enterohepatic circulation. Moreover, transplant of the microbiota from humans harboring elevated plasma cholesterol levels to recipient mice induced a phenotype of high plasma cholesterol levels in association with a low hepatic cholesterol synthesis and high intestinal absorption pattern. Recipient mice phenotypes correlated with several specific bacterial phylotypes affiliated to Betaproteobacteria, Alistipes, Bacteroides, and Barnesiella taxa. CONCLUSIONS These results indicate that the intestinal microbiota determines the circulating cholesterol level and may thus represent a novel therapeutic target in the management of dyslipidemia and cardiovascular diseases.
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Affiliation(s)
- Tiphaine Le Roy
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France.,Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Emelyne Lécuyer
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France
| | - Benoit Chassaing
- Neuroscience Institute and Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA.,INSERM, U1016, team "Mucosal microbiota in chronic inflammatory diseases", Paris, France.,Université de Paris, Paris, France
| | - Moez Rhimi
- Institut Micalis, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Marie Lhomme
- Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Samira Boudebbouze
- Institut Micalis, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Farid Ichou
- Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Júlia Haro Barceló
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France
| | - Thierry Huby
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France.,Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Maryse Guerin
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France.,Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Philippe Giral
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France.,Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France
| | - Emmanuelle Maguin
- Institut Micalis, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Nathalie Kapel
- Laboratoire de Coprologie Fonctionnelle, Hôpital Pitié-Salpêtrière, Paris, France.,EA 4065 "Ecosystème intestinal, probiotiques, antibiotiques", Faculté des Sciences Pharmaceutiques et Biologiques Paris Descartes, Paris, France
| | - Philippe Gérard
- Institut Micalis, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Karine Clément
- Sorbonne/INSERM, UMRS 1269, Nutrition et obésités : approches systémiques (nutriOmics), Hôpital Pitié-Salpêtrière, Paris, France
| | - Philippe Lesnik
- INSERM, UMRS 1166, team "Integrative Biology of Atherosclerosis", Sorbonne Universités, Hôpital Pitié-Salpêtrière, Paris, France. .,Institute of Cardiometabolism and Nutrition (ICAN), Hôpital Pitié-Salpêtrière, Paris, France.
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23
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Wijers M, Zanoni P, Liv N, Vos DY, Jäckstein MY, Smit M, Wilbrink S, Wolters JC, van der Veen YT, Huijkman N, Dekker D, Kloosterhuis N, van Dijk TH, Billadeau DD, Kuipers F, Klumperman J, von Eckardstein A, Kuivenhoven JA, van de Sluis B. The hepatic WASH complex is required for efficient plasma LDL and HDL cholesterol clearance. JCI Insight 2019; 4:126462. [PMID: 31167970 DOI: 10.1172/jci.insight.126462] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 04/17/2019] [Indexed: 12/21/2022] Open
Abstract
The evolutionary conserved Wiskott-Aldrich syndrome protein and SCAR homolog (WASH) complex is one of the crucial multiprotein complexes that facilitates endosomal recycling of transmembrane proteins. Defects in WASH components have been associated with inherited developmental and neurological disorders in humans. Here, we show that hepatic ablation of the WASH component Washc1 in chow-fed mice increases plasma concentrations of cholesterol in both LDLs and HDLs, without affecting hepatic cholesterol content, hepatic cholesterol synthesis, biliary cholesterol excretion, or hepatic bile acid metabolism. Elevated plasma LDL cholesterol was related to reduced hepatocytic surface levels of the LDL receptor (LDLR) and the LDLR-related protein LRP1. Hepatic WASH ablation also reduced the surface levels of scavenger receptor class B type I and, concomitantly, selective uptake of HDL cholesterol into the liver. Furthermore, we found that WASHC1 deficiency increases LDLR proteolysis by the inducible degrader of LDLR, but does not affect proprotein convertase subtilisin/kexin type 9-mediated LDLR degradation. Remarkably, however, loss of hepatic WASHC1 may sensitize LDLR for proprotein convertase subtilisin/kexin type 9-induced degradation. Altogether, these findings identify the WASH complex as a regulator of LDL as well as HDL metabolism and provide in vivo evidence for endosomal trafficking of scavenger receptor class B type I in hepatocytes.
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Affiliation(s)
- Melinde Wijers
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Paolo Zanoni
- Institute for Clinical Chemistry, University Hospital Zurich, Zurich, Switzerland; Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Nalan Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Dyonne Y Vos
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Michelle Y Jäckstein
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Marieke Smit
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Sanne Wilbrink
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Justina C Wolters
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Ydwine T van der Veen
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Nicolette Huijkman
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Daphne Dekker
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Niels Kloosterhuis
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Theo H van Dijk
- Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Daniel D Billadeau
- Department of Immunology and Biochemistry, Division of Oncology Research, Mayo Clinic, Rochester, New York, USA
| | - Folkert Kuipers
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands.,Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Judith Klumperman
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Arnold von Eckardstein
- Institute for Clinical Chemistry, University Hospital Zurich, Zurich, Switzerland; Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Jan Albert Kuivenhoven
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Bart van de Sluis
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
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24
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Yu XH, Zhang DW, Zheng XL, Tang CK. Cholesterol transport system: An integrated cholesterol transport model involved in atherosclerosis. Prog Lipid Res 2018; 73:65-91. [PMID: 30528667 DOI: 10.1016/j.plipres.2018.12.002] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 10/30/2018] [Accepted: 12/01/2018] [Indexed: 02/07/2023]
Abstract
Atherosclerosis, the pathological basis of most cardiovascular disease (CVD), is closely associated with cholesterol accumulation in the arterial intima. Excessive cholesterol is removed by the reverse cholesterol transport (RCT) pathway, representing a major antiatherogenic mechanism. In addition to the RCT, other pathways are required for maintaining the whole-body cholesterol homeostasis. Thus, we propose a working model of integrated cholesterol transport, termed the cholesterol transport system (CTS), to describe body cholesterol metabolism. The novel model not only involves the classical view of RCT but also contains other steps, such as cholesterol absorption in the small intestine, low-density lipoprotein uptake by the liver, and transintestinal cholesterol excretion. Extensive studies have shown that dysfunctional CTS is one of the major causes for hypercholesterolemia and atherosclerosis. Currently, several drugs are available to improve the CTS efficiently. There are also several therapeutic approaches that have entered into clinical trials and shown considerable promise for decreasing the risk of CVD. In recent years, a variety of novel findings reveal the molecular mechanisms for the CTS and its role in the development of atherosclerosis, thereby providing novel insights into the understanding of whole-body cholesterol transport and metabolism. In this review, we summarize the latest advances in this area with an emphasis on the therapeutic potential of targeting the CTS in CVD patients.
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Affiliation(s)
- Xiao-Hua Yu
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Medical Research Experiment Center, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, Hunan 421001, China
| | - Da-Wei Zhang
- Department of Pediatrics and Group on the Molecular and Cell Biology of Lipids, University of Alberta, Alberta, Canada
| | - Xi-Long Zheng
- Department of Biochemistry and Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Health Sciences Center, 3330 Hospital Dr NW, Calgary, Alberta T2N 4N1, Canada
| | - Chao-Ke Tang
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, Medical Research Experiment Center, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, Hunan 421001, China.
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25
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Anastasius M, Luquain-Costaz C, Kockx M, Jessup W, Kritharides L. A critical appraisal of the measurement of serum 'cholesterol efflux capacity' and its use as surrogate marker of risk of cardiovascular disease. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1257-1273. [PMID: 30305243 DOI: 10.1016/j.bbalip.2018.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 08/02/2018] [Accepted: 08/03/2018] [Indexed: 12/15/2022]
Abstract
The 'cholesterol efflux capacity (CEC)' assay is a simple in vitro measure of the capacities of individual sera to promote the first step of the reverse cholesterol transport pathway, the delivery of cellular cholesterol to plasma HDL. This review describes the cell biology of this model and critically assesses its application as a marker of cardiovascular risk. We describe the pathways for cell cholesterol export, current cell models used in the CEC assay with their limitations and consider the contribution that measurement of serum CEC provides to our understanding of HDL function in vivo.
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Affiliation(s)
- Malcolm Anastasius
- ANZAC Research Institute, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW, Australia
| | | | - Maaike Kockx
- ANZAC Research Institute, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW, Australia
| | - Wendy Jessup
- ANZAC Research Institute, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW, Australia
| | - Leonard Kritharides
- ANZAC Research Institute, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW, Australia; Cardiology Department, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW, Australia.
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26
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Ren K, Jiang T, Zhao GJ. Quercetin induces the selective uptake of HDL-cholesterol via promoting SR-BI expression and the activation of the PPARγ/LXRα pathway. Food Funct 2018; 9:624-635. [PMID: 29292466 DOI: 10.1039/c7fo01107e] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Reverse cholesterol transport (RCT) is the process to deliver cholesterol to the liver for further excretion and involves scavenger receptor class B type I (SR-BI)-mediated selective lipid uptake (SLU) from high-density lipoprotein cholesterol (HDL-C). The up-regulation of hepatic SR-BI expression accelerates HDL-C clearance in circulation and impedes the development of atherosclerosis (AS). In the present study, we explored the modulation of hepatic SR-BI expression and SR-BI-mediated SLU by quercetin, a natural flavonoid compound in the diet with a favorable role in cardiovascular disorders. We found that quercetin significantly increased the expression level of SR-BI in HepG2 cells in a concentration- and time-dependent manner. Besides, quercetin had stimulatory effects on the binding of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil)-labeled HDL to hepatocytes and 125I/3H-CE-HDL association. Treatment with small interfering RNA (siRNA) or SR-BI specific inhibitor, BLT-1, inhibited quercetin-induced Dil-HDL binding and selective HDL-C uptake. Treatment with quercetin increased both proliferator-activated receptor γ (PPARγ) and liver X receptor α (LXRα) levels. Additionally, the quercetin-induced expression of SR-BI, Dil-HDL binding and the selective uptake of HDL-C were significantly attenuated by treatment with PPARγ siRNA, LXRα siRNA, and their antagonists, respectively. In C57BL/6 mice, quercetin administration potently increased SR-BI, PPARγ and LXRα levels and lipid accumulation in the liver. Altogether, our results suggest that quercetin-induced up-regulation of SR-BI and subsequent lipid uptake in hepatocytes might contribute to its beneficial effects on cholesterol homeostasis and atherogenesis.
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Affiliation(s)
- Kun Ren
- Department of Histology and Embryology, Guilin Medical University, Guilin, Guangxi 541004, China.
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27
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Huang J, Wang Y, Ying C, Liu L, Lou Z. Effects of mulberry leaf on experimental hyperlipidemia rats induced by high-fat diet. Exp Ther Med 2018; 16:547-556. [PMID: 30116313 PMCID: PMC6090255 DOI: 10.3892/etm.2018.6254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 03/09/2018] [Indexed: 12/25/2022] Open
Abstract
Hypercholesterolemia is a major risk factor for cardiovascular disease. Mulberry leaf (ML) is a Traditional Chinese Medicine used to treat hyperlipidemia in clinical settings. The aim of the present study was to identify the potential effect and possible target of ML in anti-hypercholesterolemia. Male Sprague-Dawley rats were fed with a high-fat diet and treated with ML for 5 weeks. Blood lipid levels, total cholesterol (TC) and total bile acid (TBA) in the liver and feces were measured to assess the effects of ML on hypercholesterolemia. Harris's hematoxylin staining and oil red O staining was applied to observe the pathological change and lipid accumulation in the liver. Immunohistochemical assay was performed to observe the location of expressions of scavenger receptor class B type I and low-density lipoprotein (LDL) receptor (-R), and western blotting was applied to determine the protein expression of ATP-binding cassette transporter G5/G8 (ABCG5/8), nuclear transcription factor peroxisome proliferator-activated receptor-α (PPARα), farnesoid-X receptor (FXR) and cholesterol 7α-hydroxylase 1 (CYP7A1). The results demonstrated that ML treatment reduced serum TC and LDL-cholesterol levels, and liver TC and TBA contents; increased serum HDL-C levels, and fecal TC and TBA contents; and alleviated hepatocyte lipid degeneration. In addition, ML treatment inhibited liver LDL-R, PPARα and FXR protein expression, promoted protein expression of CYP7A1, and maintained the ratio of ABCG5/ABCG8. The findings of the present study provide a positive role of ML on cholesterol clearance via promoting cholesterol and TBA execration via FXR- and CYP7A1-mediated pathways; RCT regulation may be a potential mechanism of ML on anti-hypercholesterolemia.
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Affiliation(s)
- Jianbo Huang
- Department of Basic Theory of Traditional Chinese Medicine, College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
| | - Yangpeng Wang
- Department of Basic Theory of Traditional Chinese Medicine, College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
| | - Chao Ying
- Institute of Materia Medica, College of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China
| | - Lei Liu
- Department of Basic Theory of Traditional Chinese Medicine, College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
| | - Zhaohuan Lou
- Institute of Materia Medica, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
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28
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Walquist MJ, Stormo SK, Østerud B, Elvevoll EO, Eilertsen KE. Cold-pressed minke whale oil reduces circulating LDL/VLDL-cholesterol, lipid oxidation and atherogenesis in apolipoprotein E-deficient mice fed a Western-type diet for 13 weeks. Nutr Metab (Lond) 2018; 15:35. [PMID: 29755576 PMCID: PMC5935995 DOI: 10.1186/s12986-018-0269-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/17/2018] [Indexed: 11/10/2022] Open
Abstract
Background Long-chain n3-polyunsaturated fatty acids (LC n3-PUFA) are well known for their anti-inflammatory activity and their impact on cardiovascular disease. Cold-pressed whale oil (CWO) has half the amount of LC n3-PUFA compared to cod liver oil (CLO). Still, there has been observed more pronounced beneficial effects on cardiovascular disease markers from intake of CWO compared to intake of CLO in human intervention studies. Extracts from CWO deprived of fatty acids have also been shown to display antioxidative and anti-inflammatory effects in vitro. The aim of this study was to investigate whether intake of a high-fat Western-type diet (WD) supplemented with CWO would prevent the development of atherosclerotic lesions in apolipoprotein E-deficient (ApoE-/-) mice. Methods Seventy female ApoE-/- mice were fed a WD containing 1% CWO, CLO or corn oil (CO). Atherosclerotic lesion formation, body and tissue weights, hepatic gene expression together with serum levels of LDL/VLDL-cholesterol, ox-LDL, total antioxidant status and various serum cardiovascular disease/proinflammatory markers were evaluated. Statistical analyses were performed using SPSS, and Shapiro-Wilk's test was performed to determine the distribution of the variables. Statistical difference was assessed using One-Way ANOVA with Tukeys' post hoc test or Kruskal-Wallis test. The hepatic relative gene expression was analysed with REST 2009 (V2.0.13). Results Mice fed CWO had less atherosclerotic lesions in the aortic arch compared to mice fed CO. Levels of LDL/VLDL-cholesterol and ox-LDL-cholesterol were also markedly reduced whereas total antioxidant levels were enhanced in mice fed CWO compared to CO-fed mice. In addition, CWO-fed mice gained less weight and several hepatic genes involved in the cholesterol metabolism were up-regulated compared to CO-fed mice. Conclusion In the present study mice fed a WD supplemented with 1% CWO had reduced formation of atherosclerotic lesions in the aortic arch, reduced serum LDL/VLDL-cholesterol and ox-LDL-cholesterol, increased serum total antioxidant status and reduced body weight compared to mice fed a WD supplemented with 1% CO.
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Affiliation(s)
- Mari Johannessen Walquist
- 1Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, 9037 Tromsø, Norway
| | | | - Bjarne Østerud
- 3Faculty of Health Science, IMB, K.G Jebsen TREC, UiT - The Arctic University of Norway, 9037 Tromsø, Norway
| | - Edel O Elvevoll
- 1Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, 9037 Tromsø, Norway
| | - Karl-Erik Eilertsen
- 1Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, 9037 Tromsø, Norway
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29
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Takiguchi S, Ayaori M, Yakushiji E, Nishida T, Nakaya K, Sasaki M, Iizuka M, Uto-Kondo H, Terao Y, Yogo M, Komatsu T, Ogura M, Ikewaki K. Hepatic Overexpression of Endothelial Lipase Lowers High-Density Lipoprotein but Maintains Reverse Cholesterol Transport in Mice: Role of Scavenger Receptor Class B Type I/ATP-Binding Cassette Transporter A1-Dependent Pathways. Arterioscler Thromb Vasc Biol 2018; 38:1454-1467. [PMID: 29748333 PMCID: PMC6039415 DOI: 10.1161/atvbaha.118.311056] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 04/11/2018] [Indexed: 01/06/2023]
Abstract
Supplemental Digital Content is available in the text. Objective— Reverse cholesterol transport (RCT) is a major mechanism by which HDL (high-density lipoprotein) protects against atherosclerosis. Endothelial lipase (EL) reportedly reduces HDL levels, which, in theory, would increase atherosclerosis. However, it remains unclear whether EL affects RCT in vivo. Approach and Results— Adenoviral vectors expressing EL or luciferase were intravenously injected into mice, and a macrophage RCT assay was performed. As expected, hepatic EL overexpression markedly reduced HDL levels. In parallel, plasma 3H-cholesterol counts from the EL-expressing mice decreased by 85% compared with control. Surprisingly, there was no difference in fecal 3H-cholesterol excretion between the groups. Kinetic studies revealed increased catabolism/hepatic uptake of 3HDL-cholesteryl ether, resulting in no change in fecal HDL-cholesteryl ester excretion in the mice. To explore underlying mechanisms for the preservation of RCT despite low HDL levels in the EL-expressing mice, we investigated the effects of hepatic SR-BI (scavenger receptor class B type I) knockdown. RCT assay revealed that knockdown of SR-BI alone reduced fecal excretion of macrophage-derived 3H-cholesterol. Interestingly, hepatic EL overexpression under SR-BI inhibition further attenuated fecal tracer counts as compared with control. Finally, we observed that EL overexpression enhanced in vivo RCT under pharmacological inhibition of hepatic ABCA1 (ATP-binding cassette transporter A1) by probucol. Conclusions— Hepatic EL expression compensates for reduced macrophage-derived cholesterol efflux to plasma because of low HDL levels by promoting cholesterol excretion to bile/feces via an SR-BI pathway, maintaining overall RCT in vivo. In contrast, EL-modified HDL might negatively regulate RCT via hepatic ABCA1. Despite extreme hypoalphalipoproteinemia, RCT is maintained in EL-expressing mice via SR-BI/ABCA1-dependent pathways.
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Affiliation(s)
- Shunichi Takiguchi
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Makoto Ayaori
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Emi Yakushiji
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Takafumi Nishida
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Kazuhiro Nakaya
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Makoto Sasaki
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Maki Iizuka
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Harumi Uto-Kondo
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Yoshio Terao
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Makiko Yogo
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Tomohiro Komatsu
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
| | - Masatsune Ogura
- Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center, Osaka, Japan (M.O.)
| | - Katsunori Ikewaki
- From the Division of Anti-Aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan (S.T., M.A., E.Y., T.N., K.N., M.S., M.I., H.U.-K., Y.T., M.Y., T.K., K.I.)
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Shen WJ, Asthana S, Kraemer FB, Azhar S. Scavenger receptor B type 1: expression, molecular regulation, and cholesterol transport function. J Lipid Res 2018; 59:1114-1131. [PMID: 29720388 DOI: 10.1194/jlr.r083121] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/26/2018] [Indexed: 12/16/2022] Open
Abstract
Cholesterol is required for maintenance of plasma membrane fluidity and integrity and for many cellular functions. Cellular cholesterol can be obtained from lipoproteins in a selective pathway of HDL-cholesteryl ester (CE) uptake without parallel apolipoprotein uptake. Scavenger receptor B type 1 (SR-B1) is a cell surface HDL receptor that mediates HDL-CE uptake. It is most abundantly expressed in liver, where it provides cholesterol for bile acid synthesis, and in steroidogenic tissues, where it delivers cholesterol needed for storage or steroidogenesis in rodents. SR-B1 transcription is regulated by trophic hormones in the adrenal gland, ovary, and testis; in the liver and elsewhere, SR-B1 is subject to posttranscriptional and posttranslational regulation. SR-B1 operates in several metabolic processes and contributes to pathogenesis of atherosclerosis, inflammation, hepatitis C virus infection, and other conditions. Here, we summarize characteristics of the selective uptake pathway and involvement of microvillar channels as facilitators of selective HDL-CE uptake. We also present the potential mechanisms of SR-B1-mediated selective cholesterol transport; the transcriptional, posttranscriptional, and posttranslational regulation of SR-B1; and the impact of gene variants on expression and function of human SR-B1. A better understanding of this unique pathway and SR-B1's role may yield improved therapies for a wide variety of conditions.
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Affiliation(s)
- Wen-Jun Shen
- Geriatric Research, Education, and Clinical Research Center (GRECC), Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304 and Division of Endocrinology, Gerontology, and Metabolism, Stanford University School of Medicine, Stanford, CA 94305
| | - Shailendra Asthana
- Drug Discovery Research Center (DDRC), Translational Health Science and Technology Institute (THSTI), NCR Biotech Science Cluster, Faridabad 121001, Haryana, India
| | - Fredric B Kraemer
- Geriatric Research, Education, and Clinical Research Center (GRECC), Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304 and Division of Endocrinology, Gerontology, and Metabolism, Stanford University School of Medicine, Stanford, CA 94305
| | - Salman Azhar
- Geriatric Research, Education, and Clinical Research Center (GRECC), Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304 and Division of Endocrinology, Gerontology, and Metabolism, Stanford University School of Medicine, Stanford, CA 94305
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31
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Linton MF, Tao H, Linton EF, Yancey PG. SR-BI: A Multifunctional Receptor in Cholesterol Homeostasis and Atherosclerosis. Trends Endocrinol Metab 2017; 28:461-472. [PMID: 28259375 PMCID: PMC5438771 DOI: 10.1016/j.tem.2017.02.001] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 01/31/2017] [Accepted: 02/01/2017] [Indexed: 02/07/2023]
Abstract
The HDL receptor scavenger receptor class B type I (SR-BI) plays crucial roles in cholesterol homeostasis, lipoprotein metabolism, and atherosclerosis. Hepatic SR-BI mediates reverse cholesterol transport (RCT) by the uptake of HDL cholesterol for routing to the bile. Through the selective uptake of HDL lipids, hepatic SR-BI modulates HDL composition and preserves HDL's atheroprotective functions of mediating cholesterol efflux and minimizing inflammation and oxidation. Macrophage and endothelial cell SR-BI inhibits the development of atherosclerosis by mediating cholesterol trafficking to minimize atherosclerotic lesion foam cell formation. SR-BI signaling also helps limit inflammation and cell death and mediates efferocytosis of apoptotic cells in atherosclerotic lesions thereby preventing vulnerable plaque formation. SR-BI is emerging as a multifunctional therapeutic target to reduce atherosclerosis development.
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Affiliation(s)
- MacRae F Linton
- Atherosclerosis Research Unit, Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-6300, USA; Atherosclerosis Research Unit, Cardiovascular Medicine, Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232-6300, USA.
| | - Huan Tao
- Atherosclerosis Research Unit, Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-6300, USA
| | - Edward F Linton
- Perelman School of Medicine, University of Pennsylvania, Jordan Medical Education Center, 6th Floor, 3400 Civic Center Blvd, Philadelphia, PA 19104-6055, USA
| | - Patricia G Yancey
- Atherosclerosis Research Unit, Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-6300, USA.
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Abstract
PURPOSE OF REVIEW To outline the roles of SR-B1 and PDZK1 in hepatic selective HDL cholesterol uptake and reverse cholesterol transport and the consequences for atherosclerosis development. RECENT FINDINGS Much of our understanding of the physiological roles of SR-B1 and PDZK1 in HDL metabolism and atherosclerosis comes from studies of genetically manipulated mice. These show SR-B1 and PDZK1 play key roles in HDL metabolism and protection against atherosclerosis. The recent identification of rare loss of function mutations in the human SCARB1 gene verifies that it plays similar roles in HDL metabolism in humans. Other rare mutations in both the human SCARB1 and PDZK1 genes remain to be characterized but may have potentially devastating consequences to SR-B1 function. SUMMARY Identification of carriers of rare mutations in human SCARB1 and PDZK1 that impair the function of their gene products and characterization of the effects of these mutations on HDL cholesterol levels and atherosclerosis will add to our understanding of the importance of HDL function and cholesterol flux, as opposed to HDL-cholesterol levels, per se, for protection against cardiovascular disease.
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Affiliation(s)
- Bernardo L Trigatti
- aDepartment of Biochemistry and Biomedical Sciences, McMaster University bThrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, Ontario, Canada
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März W, Kleber ME, Scharnagl H, Speer T, Zewinger S, Ritsch A, Parhofer KG, von Eckardstein A, Landmesser U, Laufs U. HDL cholesterol: reappraisal of its clinical relevance. Clin Res Cardiol 2017; 106:663-675. [PMID: 28342064 PMCID: PMC5565659 DOI: 10.1007/s00392-017-1106-1] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 03/14/2017] [Indexed: 12/31/2022]
Abstract
Background While several lines of evidence prove that elevated concentrations of low-density lipoproteins (LDL) causally contribute to the development of atherosclerosis and its clinical consequences, high-density lipoproteins are still widely believed to exert atheroprotective effects. Hence, HDL cholesterol (HDL-C) is in general still considered as “good cholesterol”. Recent research, however, suggests that this might not always be the case and that a fundamental reassessment of the clinical significance of HDL-C is warranted. Method This review article is based on a selective literature review. Results In individuals without a history of cardiovascular events, low concentrations of HDL-C are inversely associated with the risk of future cardiovascular events. This relationship may, however, not apply to patients with metabolic disorders or manifest cardiovascular disease. The classical function of HDL is to mobilise cholesterol from extrahepatic tissues for delivery to the liver for excretion. These roles in cholesterol metabolism as well as many other biological functions of HDL particles are dependent on the number as well as protein and lipid composition of HDL particles. They are poorly reflected by the HDL-C concentration. HDL can even exert negative vascular effects, if its composition is pathologically altered. High serum HDL-C is therefore no longer regarded protective. In line with this, recent pharmacological approaches to raise HDL-C concentration have not been able to show reductions of cardiovascular outcomes. Conclusion In contrast to LDL cholesterol (LDL-C), HDL-C correlates with cardiovascular risk only in healthy individuals. The calculation of the ratio of LDL-C to HDL-C is not useful for all patients. Low HDL-C should prompt examination of additional metabolic and inflammatory pathologies. An increase in HDL-C through lifestyle change (smoking cessation, physical exercise) has positive effects and is recommended. However, HDL-C is currently not a valid target for drug therapy.
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Affiliation(s)
- Winfried März
- Medizinische Klinik V (Nephrologie, Hypertensiologie, Rheumatologie, Endokrinologie, Diabetelogie), Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Germany.,Klinisches Institut für Medizinische und Chemische Labordiagnostik, Medizinische Universität Graz, Graz, Austria.,Synlab Akademie, synlab Holding Deutschland GmbH, Mannheim und Augsburg, Augsburg, Germany
| | - Marcus E Kleber
- Medizinische Klinik V (Nephrologie, Hypertensiologie, Rheumatologie, Endokrinologie, Diabetelogie), Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Germany.,Institut für Ernährungswissenschaften, Friedrich Schiller Universität Jena, Jena, Germany
| | - Hubert Scharnagl
- Klinisches Institut für Medizinische und Chemische Labordiagnostik, Medizinische Universität Graz, Graz, Austria
| | - Timotheus Speer
- Klinik für Innere Medizin IV, Nieren- und Hochdruckkrankheiten, Universitätsklinikum des Saarlandes, 66421, Homburg, Saarland, Germany
| | - Stephen Zewinger
- Klinik für Innere Medizin IV, Nieren- und Hochdruckkrankheiten, Universitätsklinikum des Saarlandes, 66421, Homburg, Saarland, Germany
| | - Andreas Ritsch
- Klinik für Innere Medizin, Medizinische Universität Innsbruck, Innsbruck, Austria
| | - Klaus G Parhofer
- Medizinische Klinik II, Klinikum der Universität München, 81377, Munich, Germany
| | | | | | - Ulrich Laufs
- Klinik für Innere Medizin III, Kardiologie, Angiologie und Internistische Intensivmedizin, IMED, Universitätsklinikum des Saarlandes, 66421, Homburg, Saarland, Germany.
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Hoekstra M. SR-BI as target in atherosclerosis and cardiovascular disease - A comprehensive appraisal of the cellular functions of SR-BI in physiology and disease. Atherosclerosis 2017; 258:153-161. [DOI: 10.1016/j.atherosclerosis.2017.01.034] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/25/2017] [Accepted: 01/27/2017] [Indexed: 12/12/2022]
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35
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März W, Kleber ME, Scharnagl H, Speer T, Zewinger S, Ritsch A, Parhofer KG, von Eckardstein A, Landmesser U, Laufs U. [Clinical importance of HDL cholesterol]. Herz 2016; 42:58-66. [PMID: 27844137 DOI: 10.1007/s00059-016-4499-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 10/14/2016] [Indexed: 11/28/2022]
Abstract
BACKROUND Each year 16-17 million determinations of high-density lipoprotein cholesterol (HDL-C) are conducted and interpreted in Germany. Recently acquired data have led to a fundamental reassessment of the clinical significance of HDL-C. METHOD This review article is based on a selective literature search. RESULTS Low HDL‑C levels usually indicate an increased cardiovascular risk, particularly in primary prevention but the epidemiological relationship between HDL‑C and the risk is complex. The HDL plays a role in the back transport and excretion of cholesterol; however, the biological functions of HDL are dependent on the protein and lipid composition, which is not reflected by the HDL‑C concentration. If the composition of HDL is pathologically altered it can also exert negative vascular effects. CONCLUSION Compared with low-density lipoprotein cholesterol (LDL-C), HDL‑C is of secondary importance for cardiovascular risk stratification and the calculation of the LDL-C:HDL‑C ratio is not useful for all patients. Low HDL‑C levels should prompt a search for additional metabolic and inflammatory pathologies. An increase in HDL‑C through lifestyle changes (e.g. smoking cessation and physical exercise) has positive effects and is recommended; however, HDL‑C is currently not a valid target for drug therapy.
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Affiliation(s)
- W März
- Medizinische Klinik V (Nephrologie, Hypertensiologie, Rheumatologie, Endokrinologie, Diabetologie), Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Deutschland.,Klinisches Institut für Medizinische und Chemische Labordiagnostik, Medizinische Universität Graz, Graz, Österreich.,Synlab Akademie, synlab Holding Deutschland GmbH, Mannheim und Augsburg, Deutschland
| | - M E Kleber
- Medizinische Klinik V (Nephrologie, Hypertensiologie, Rheumatologie, Endokrinologie, Diabetologie), Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Deutschland.,Institut für Ernährungswissenschaften, Friedrich-Schiller-Universität Jena, Jena, Deutschland
| | - H Scharnagl
- Klinisches Institut für Medizinische und Chemische Labordiagnostik, Medizinische Universität Graz, Graz, Österreich
| | - T Speer
- Klinik für Innere Medizin IV, Nieren- und Hochdruckkrankheiten, Universitätsklinikum des Saarlandes, 66421, Homburg/Saar, Deutschland
| | - S Zewinger
- Klinik für Innere Medizin IV, Nieren- und Hochdruckkrankheiten, Universitätsklinikum des Saarlandes, 66421, Homburg/Saar, Deutschland
| | - A Ritsch
- Klinik für Innere Medizin, Medizinische Universität Innsbruck, Innsbruck, Österreich
| | - K G Parhofer
- Medizinische Klinik II, Klinikum der Universität München, 81377, München, Deutschland
| | - A von Eckardstein
- Institut für Klinische Chemie, Universitätsspital, 8091, Zürich, Schweiz
| | - U Landmesser
- Klinik für Kardiologie, Charité, Berlin, Deutschland
| | - U Laufs
- Klinik für Innere Medizin III, Kardiologie, Angiologie und Internistische Intensivmedizin (IMED), Universitätsklinikum des Saarlandes, 66421, Homburg/Saar, Deutschland.
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Gutierrez-Pajares JL, Ben Hassen C, Chevalier S, Frank PG. SR-BI: Linking Cholesterol and Lipoprotein Metabolism with Breast and Prostate Cancer. Front Pharmacol 2016; 7:338. [PMID: 27774064 PMCID: PMC5054001 DOI: 10.3389/fphar.2016.00338] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/12/2016] [Indexed: 12/16/2022] Open
Abstract
Studies have demonstrated the significant role of cholesterol and lipoprotein metabolism in the progression of cancer. The SCARB1 gene encodes the scavenger receptor class B type I (SR-BI), which is an 82-kDa glycoprotein with two transmembrane domains separated by a large extracellular loop. SR-BI plays an important role in the regulation of cholesterol exchange between cells and high-density lipoproteins. Accordingly, hepatic SR-BI has been shown to play an essential role in the regulation of the reverse cholesterol transport pathway, which promotes the removal and excretion of excess body cholesterol. In the context of atherosclerosis, SR-BI has been implicated in the regulation of intracellular signaling, lipid accumulation, foam cell formation, and cellular apoptosis. Furthermore, since lipid metabolism is a relevant target for cancer treatment, recent studies have focused on examining the role of SR-BI in this pathology. While signaling pathways have initially been explored in non-tumoral cells, studies with cancer cells have now demonstrated SR-BI's function in tumor progression. In this review, we will discuss the role of SR-BI during tumor development and malignant progression. In addition, we will provide insights into the transcriptional and post-transcriptional regulation of the SCARB1 gene. Overall, studying the role of SR-BI in tumor development and progression should allow us to gain useful information for the development of new therapeutic strategies.
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Affiliation(s)
- Jorge L Gutierrez-Pajares
- Université François Rabelais de Tours, Faculté de Médecine-INSERM UMR1069 "Nutrition, Croissance et Cancer" Tours, France
| | - Céline Ben Hassen
- Université François Rabelais de Tours, Faculté de Médecine-INSERM UMR1069 "Nutrition, Croissance et Cancer" Tours, France
| | - Stéphan Chevalier
- Université François Rabelais de Tours, Faculté de Médecine-INSERM UMR1069 "Nutrition, Croissance et Cancer" Tours, France
| | - Philippe G Frank
- Université François Rabelais de Tours, Faculté de Médecine-INSERM UMR1069 "Nutrition, Croissance et Cancer" Tours, France
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The unfolded protein response is a negative regulator of scavenger receptor class B, type I (SR-BI) expression. Biochem Biophys Res Commun 2016; 479:557-562. [DOI: 10.1016/j.bbrc.2016.09.110] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 09/21/2016] [Indexed: 11/23/2022]
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38
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Trigatti BL, Hegele RA. Rare Genetic Variants and High-Density Lipoprotein. Arterioscler Thromb Vasc Biol 2016; 36:e53-5. [DOI: 10.1161/atvbaha.116.307688] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Bernardo L. Trigatti
- From the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada (B.L.T.); Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada (B.L.T.); and Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada (R.A.H.)
| | - Robert A. Hegele
- From the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada (B.L.T.); Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada (B.L.T.); and Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada (R.A.H.)
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Yang H, Yan L, Qian P, Duan H, Wu J, Li B, Wang S. Icariin inhibits foam cell formation by down-regulating the expression of CD36 and up-regulating the expression of SR-BI. J Cell Biochem 2016; 116:580-8. [PMID: 25389062 DOI: 10.1002/jcb.25009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 11/06/2014] [Indexed: 12/21/2022]
Abstract
Icariin is an important pharmacologically active flavonol diglycoside that can inhibit inflammation in lipopolysaccharide (LPS)-stimulated macrophages. However, little is known about the molecular mechanisms underlying the inhibitory effect of Icariin in the formation of foam cells. In this study, macrophages were cultured with LPS and oxidized low-density lipoprotein (oxLDL) in the presence or absence of Icariin. RT-PCR and western blot were used to detect the levels of mRNA and protein expression of CD36, scavenger receptor class B type I (SR-BI) and the phosphorylation of p38MAPK. It was demonstrated that 4 µM or 20 µM Icariin treatment significantly inhibited the cholesterol ester (CE)/total cholesterol (TC) and oxLDL-mediated foam cell formation (P < 0.05). The binding of oxLDL to LPS-activated macrophages was also significantly hindered by Icariin (P < 0.05). Furthermore, Icariin down-regulated the expression of CD36 in LPS-activated macrophages in a dose-dependent manner and CD36 over-expression restored the inhibitory effect of Icariin on foam cell formation. The phosphorylation of p38MAPK was reduced by Icariin, indicating that Icariin reduced the expression of CD36 through the p38MAPK pathway. In addition, Icariin up-regulated SR-BI protein expression in a dose-dependent manner, and SR-BI gene silencing restored the inhibitory effect of Icariin on foam cell formation. These data demonstrate that Icariin inhibited foam cell formation by down-regulating the expression of CD36 and up-regulating the expression of SR-BI. Therefore, our findings provide a new explanation as to why Icariin could inhibit atherosclerosis.
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Affiliation(s)
- Haitao Yang
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, 450003, China
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Cameron SJ, Morrell CN, Bao C, Swaim AF, Rodriguez A, Lowenstein CJ. A Novel Anti-Inflammatory Effect for High Density Lipoprotein. PLoS One 2015; 10:e0144372. [PMID: 26680360 PMCID: PMC4683005 DOI: 10.1371/journal.pone.0144372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 11/17/2015] [Indexed: 11/21/2022] Open
Abstract
High density lipoprotein has anti-inflammatory effects in addition to mediating reverse cholesterol transport. While many of the chronic anti-inflammatory effects of high density lipoprotein (HDL) are attributed to changes in cell adhesion molecules, little is known about acute signal transduction events elicited by HDL in endothelial cells. We now show that high density lipoprotein decreases endothelial cell exocytosis, the first step in leukocyte trafficking. ApoA-I, a major apolipoprotein of HDL, mediates inhibition of endothelial cell exocytosis by interacting with endothelial scavenger receptor-BI which triggers an intracellular protective signaling cascade involving protein kinase C (PKC). Other apolipoproteins within the HDL particle have only modest effects upon endothelial exocytosis. Using a human primary culture of endothelial cells and murine apo-AI knockout mice, we show that apo-AI prevents endothelial cell exocytosis which limits leukocyte recruitment. These data suggest that high density lipoprotein may inhibit diseases associated with vascular inflammation in part by blocking endothelial exocytosis.
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Affiliation(s)
- Scott J. Cameron
- Departments of Medicine, Division of Cardiology, University of Rochester School of Medicine, Box 679, 601 Elmwood Avenue, Rochester, NY, 14652, United States of America
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Box CVRI, 601 Elmwood Avenue, Rochester, NY, 14652, United States of America
- * E-mail:
| | - Craig N. Morrell
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Box CVRI, 601 Elmwood Avenue, Rochester, NY, 14652, United States of America
- Department of Comparative Medicine, The Johns Hopkins University School of Medicine 733 N. Broadway, MRB 827, Baltimore, MD, 21205, United States of America
| | - Clare Bao
- Department of Medicine, The Johns Hopkins University School of Medicine, 950 Ross Building, 720 Rutland Ave, Baltimore, MD, 21205, United States of America
| | - AnneMarie F. Swaim
- Department of Comparative Medicine, The Johns Hopkins University School of Medicine 733 N. Broadway, MRB 827, Baltimore, MD, 21205, United States of America
| | - Annabelle Rodriguez
- Department of Cell Biology, University of Connecticut School of Medicine, E5050, 263 Farmington Avenue, Farmington, CT, 06030, United States of America
| | - Charles J. Lowenstein
- Departments of Medicine, Division of Cardiology, University of Rochester School of Medicine, Box 679, 601 Elmwood Avenue, Rochester, NY, 14652, United States of America
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Box CVRI, 601 Elmwood Avenue, Rochester, NY, 14652, United States of America
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Corticosteroid Therapy Benefits Septic Mice With Adrenal Insufficiency But Harms Septic Mice Without Adrenal Insufficiency. Crit Care Med 2015; 43:e490-8. [PMID: 26308430 PMCID: PMC9798902 DOI: 10.1097/ccm.0000000000001264] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Corticosteroid therapy is frequently used in septic patients given the rationale that there is an increased demand for corticosteroid in sepsis, and up to 60% of severe septic patients experience adrenal insufficiency. However, the efficacy of corticosteroid therapy and whether the therapy should be based on the results of adrenal function testing are highly controversial. The lack of an adrenal insufficiency animal model and our poor understanding of the pathogenesis caused by adrenal insufficiency present significant barriers to address this long-standing clinical issue. DESIGN Prospective experimental study. SETTING University laboratory. SUBJECTS Scavenger receptor BI null and adrenal-specific scavenger receptor BI null mice. INTERVENTIONS Sepsis was induced by cecal ligation and puncture. MEASUREMENTS AND MAIN RESULTS Using scavenger receptor BI mice as the first relative adrenal insufficiency animal model, we found that corticosteroid therapy significantly improved the survival in cecal ligation and puncture-treated scavenger receptor BI mice but causes more septic death in wild-type mice. We identified a corticosteroid cocktail that provides effective protection 18 hours post cecal ligation and puncture; using adrenal-specific scavenger receptor BI mice as an inducible corticosteroid-deficient animal model, we found that inducible corticosteroid specifically suppresses interleukin-6 production without affecting tumor necrosis factor-α, nitric oxide, and interleukin-10 production. We further found that inducible corticosteroid does not induce peripheral lymphocyte apoptosis but promotes phagocytic activity of macrophages and neutrophils. CONCLUSIONS This study demonstrates that corticosteroid treatment benefits mice with adrenal insufficiency but harms mice without adrenal insufficiency. This study also reveals that inducible corticosteroid has both immunosuppressive and immunopermissive properties, suppressing interleukin-6 production, promoting phagocytosis of immune effector cells, but not inducing peripheral lymphocyte apoptosis. These findings support our hypothesis that corticosteroid is an effective therapy for a subgroup of septic patients with adrenal insufficiency but harms septic patients without adrenal insufficiency and encourage further efforts to test this hypothesis in clinic.
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Endothelial Expression of Scavenger Receptor Class B, Type I Protects against Development of Atherosclerosis in Mice. BIOMED RESEARCH INTERNATIONAL 2015; 2015:607120. [PMID: 26504816 PMCID: PMC4609362 DOI: 10.1155/2015/607120] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 07/10/2015] [Accepted: 07/24/2015] [Indexed: 11/23/2022]
Abstract
The role of scavenger receptor class B, type I (SR-BI) in endothelial cells (EC) was examined in several novel transgenic mouse models expressing SR-BI in endothelium of mice with normal C57Bl6/N, apoE-KO, or Scarb1-KO backgrounds. Mice were also created expressing SR-BI exclusively in endothelium and liver. Endothelial expression of the Tie2-Scarb1 transgene had no significant effect on plasma lipoprotein levels in mice on a normal chow diet but on an atherogenic diet, significantly decreased plasma cholesterol levels, increased plasma HDL cholesterol (HDL-C) levels, and protected mice against atherosclerosis. In 8-month-old apoE-KO mice fed a normal chow diet, the Tie2-Scarb1 transgene decreased aortic lesions by 24%. Mice expressing SR-BI only in EC and liver had a 1.5 ± 0.1-fold increase in plasma cholesterol compared to mice synthesizing SR-BI only in liver. This elevation was due mostly to increased HDL-C. In EC culture studies, SR-BI was found to be present in both basolateral and apical membranes but greater cellular uptake of cholesterol from HDL was found in the basolateral compartment. In summary, enhanced expression of SR-BI in EC resulted in a less atherogenic lipoprotein profile and decreased atherosclerosis, suggesting a possible role for endothelial SR-BI in the flux of cholesterol across EC.
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Zamora DA, Downs KP, Ullevig SL, Tavakoli S, Kim HS, Qiao M, Greaves DR, Asmis R. Glutaredoxin 2a overexpression in macrophages promotes mitochondrial dysfunction but has little or no effect on atherogenesis in LDL-receptor null mice. Atherosclerosis 2015; 241:69-78. [PMID: 25966442 PMCID: PMC4466159 DOI: 10.1016/j.atherosclerosis.2015.04.805] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 04/23/2015] [Accepted: 04/24/2015] [Indexed: 12/31/2022]
Abstract
AIMS Reactive oxygen species (ROS)-mediated formation of mixed disulfides between critical cysteine residues in proteins and glutathione, a process referred to as protein S-glutathionylation, can lead to loss of enzymatic activity and protein degradation. Since mitochondria are a major source of ROS and a number of their proteins are susceptible to protein-S-glutathionylation, we examined if overexpression of mitochondrial thioltranferase glutaredoxin 2a (Grx2a) in macrophages of dyslipidemic atherosclerosis-prone mice would prevent mitochondrial dysfunction and protect against atherosclerotic lesion formation. METHODS AND RESULTS We generated transgenic Grx2aMac(LDLR-/-) mice, which overexpress Grx2a as an EGFP fusion protein under the control of the macrophage-specific CD68 promoter. Transgenic mice and wild type siblings were fed a high fat diet for 14 weeks at which time we assessed mitochondrial bioenergetic function in peritoneal macrophages and atherosclerotic lesion formation. Flow cytometry and Western blot analysis demonstrated transgene expression in blood monocytes and peritoneal macrophages isolated from Grx2aMac(LDLR-/-) mice, and fluorescence confocal microscopy studies confirmed that Grx2a expression was restricted to the mitochondria of monocytic cells. Live-cell bioenergetic measurements revealed impaired mitochondrial ATP turnover in macrophages isolated from Grx2aMac(LDLR-/-) mice compared to macrophages isolated from non-transgenic mice. However, despite impaired mitochondrial function in macrophages of Grx2aMac(LDLR-/-) mice, we observed no significant difference in the severity of atherosclerosis between wildtype and Grx2aMac(LDLR-/-) mice. CONCLUSION Our findings suggest that increasing Grx2a activity in macrophage mitochondria disrupts mitochondrial respiration and ATP production, but without affecting the proatherogenic potential of macrophages. Our data suggest that macrophages are resistant against moderate mitochondrial dysfunction and rely on alternative pathways for ATP synthesis to support the energetic requirements.
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Affiliation(s)
- D A Zamora
- Department of Biology, Trinity University, San Antonio, USA
| | - K P Downs
- Department of Clinical Laboratory Sciences, University of Texas Health Science Center at San Antonio, USA
| | - S L Ullevig
- Department of Kinesiology, Health, and Nutrition, University of Texas at San Antonio, San Antonio, USA
| | - S Tavakoli
- Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, USA
| | - H S Kim
- Department of Clinical Laboratory Sciences, University of Texas Health Science Center at San Antonio, USA
| | - M Qiao
- Department of Clinical Laboratory Sciences, University of Texas Health Science Center at San Antonio, USA
| | - D R Greaves
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - R Asmis
- Department of Clinical Laboratory Sciences, University of Texas Health Science Center at San Antonio, USA; Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, USA; Department of Biochemistry, University of Texas Health Science Center at San Antonio, USA.
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44
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Tao H, Yancey PG, Babaev VR, Blakemore JL, Zhang Y, Ding L, Fazio S, Linton MF. Macrophage SR-BI mediates efferocytosis via Src/PI3K/Rac1 signaling and reduces atherosclerotic lesion necrosis. J Lipid Res 2015; 56:1449-60. [PMID: 26059978 PMCID: PMC4513986 DOI: 10.1194/jlr.m056689] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Indexed: 12/13/2022] Open
Abstract
Macrophage apoptosis and efferocytosis are key determinants of atherosclerotic plaque inflammation and necrosis. Bone marrow transplantation studies in ApoE- and LDLR-deficient mice revealed that hematopoietic scavenger receptor class B type I (SR-BI) deficiency results in severely defective efferocytosis in mouse atherosclerotic lesions, resulting in a 17-fold higher ratio of free to macrophage-associated dead cells in lesions containing SR-BI−/− cells, 5-fold more necrosis, 65.2% less lesional collagen content, nearly 7-fold higher dead cell accumulation, and 2-fold larger lesion area. Hematopoietic SR-BI deletion elicited a maladaptive inflammatory response [higher interleukin (IL)-1β, IL-6, and TNF-α lower IL-10 and transforming growth factor β]. Efferocytosis of apoptotic thymocytes was reduced by 64% in SR-BI−/− versus WT macrophages, both in vitro and in vivo. In response to apoptotic cells, macrophage SR-BI bound with phosphatidylserine and induced Src phosphorylation and cell membrane recruitment, which led to downstream activation of phosphoinositide 3-kinase (PI3K) and Ras-related C3 botulinum toxin substrate 1 (Rac1) for engulfment and clearance of apoptotic cells, as inhibition of Src decreased PI3K, Rac1-GTP, and efferocytosis in WT cells. Pharmacological inhibition of Rac1 reduced macrophage efferocytosis in a SR-BI-dependent fashion, and activation of Rac1 corrected the defective efferocytosis in SR-BI−/− macrophages. Thus, deficiency of macrophage SR-BI promotes defective efferocytosis signaling via the Src/PI3K/Rac1 pathway, resulting in increased plaque size, necrosis, and inflammation.
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Affiliation(s)
- Huan Tao
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Patricia G Yancey
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Vladimir R Babaev
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - John L Blakemore
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Youmin Zhang
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Lei Ding
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Sergio Fazio
- Department of Medicine, Physiology, and Pharmacology, Center of Preventive Cardiology, Oregon Health and Science University, Portland, OR 97239
| | - MacRae F Linton
- Department of Medicine, Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232 Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232
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Nishi H, Fisher EA. Cholesterol homeostasis regulation by miR-223: basic science mechanisms and translational implications. Circ Res 2015; 116:1112-4. [PMID: 25814681 DOI: 10.1161/circresaha.115.305467] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Hitoo Nishi
- From the Marc and Ruti Bell Program in Vascular Biology, Center for the Prevention of Cardiovascular Disease, Departments of Medicine (Cardiology) and Cell Biology, New York University School of Medicine
| | - Edward A Fisher
- From the Marc and Ruti Bell Program in Vascular Biology, Center for the Prevention of Cardiovascular Disease, Departments of Medicine (Cardiology) and Cell Biology, New York University School of Medicine.
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Zhao Y, Hoekstra M, Korporaal SJA, Van Berkel TJC, Van Eck M. HDL Receptor Scavenger Receptor BI. Atherosclerosis 2015. [DOI: 10.1002/9781118828533.ch25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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Ecto-F1-ATPase/P2Y pathways in metabolic and vascular functions of high density lipoproteins. Atherosclerosis 2015; 238:89-100. [DOI: 10.1016/j.atherosclerosis.2014.11.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/12/2014] [Accepted: 11/13/2014] [Indexed: 12/15/2022]
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Abstract
High-density lipoprotein (HDL) is considered to be an anti-atherogenic lipoprotein moiety. Generation of genetically modified (total body and tissue-specific knockout) mouse models has significantly contributed to our understanding of HDL function. Here we will review data from knockout mouse studies on the importance of HDL's major alipoprotein apoA-I, the ABC transporters A1 and G1, lecithin:cholesterol acyltransferase, phospholipid transfer protein, and scavenger receptor BI for HDL's metabolism and its protection against atherosclerosis in mice. The initial generation and maturation of HDL particles as well as the selective delivery of its cholesterol to the liver are essential parameters in the life cycle of HDL. Detrimental atherosclerosis effects observed in response to HDL deficiency in mice cannot be solely attributed to the low HDL levels per se, as the low HDL levels are in most models paralleled by changes in non-HDL-cholesterol levels. However, the cholesterol efflux function of HDL is of critical importance to overcome foam cell formation and the development of atherosclerotic lesions in mice. Although HDL is predominantly studied for its atheroprotective action, the mouse data also suggest an essential role for HDL as cholesterol donor for steroidogenic tissues, including the adrenals and ovaries. Furthermore, it appears that a relevant interaction exists between HDL-mediated cellular cholesterol efflux and the susceptibility to inflammation, which (1) provides strong support for the novel concept that inflammation and metabolism are intertwining biological processes and (2) identifies the efflux function of HDL as putative therapeutic target also in other inflammatory diseases than atherosclerosis.
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Affiliation(s)
- Menno Hoekstra
- Division of Biopharmaceutics, Gorlaeus Laboratories, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333CC, Leiden, The Netherlands,
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Martineau C, Martin-Falstrault L, Brissette L, Moreau R. Gender- and region-specific alterations in bone metabolism in Scarb1-null female mice. J Endocrinol 2014; 222:277-88. [PMID: 24928939 DOI: 10.1530/joe-14-0147] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A positive correlation between plasma levels of HDL and bone mass has been reported by epidemiological studies. As scavenger receptor class B, type I (SR-BI), the gene product of Scarb1, is known to regulate HDL metabolism, we recently characterized bone metabolism in Scarb1-null mice. These mice display high femoral bone mass associated with enhanced bone formation. As gender differences have been reported in HDL metabolism and SR-BI function, we investigated gender-specific bone alterations in Scarb1-null mice by microtomography and histology. We found 16% greater relative bone volume and 39% higher bone formation rate in the vertebrae from 2-month-old Scarb1-null females. No such alteration was seen in males, indicating gender- and region-specific differences in skeletal phenotype. Total and HDL-associated cholesterol levels, as well as ACTH plasma levels, were increased in both Scarb1-null genders, the latter being concurrent to impaired corticosterone response to fasting. Plasma levels of estradiol did not differ between null and WT females, suggesting that the estrogen metabolism alteration is not relevant to the higher vertebral bone mass in female Scarb1-null mice. Constitutively, high plasma levels of leptin along with 2.5-fold increase in its expression in white adipose tissue were measured in female Scarb1-null mice only. In vitro exposure of bone marrow stromal cells to ACTH and leptin promoted osteoblast differentiation as evidenced by increased gene expression of osterix and collagen type I alpha. Our results suggest that hyperleptinemia may account for the gender-specific high bone mass seen in the vertebrae of female Scarb1-null mice.
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Affiliation(s)
- Corine Martineau
- Laboratoire du Métabolisme OsseuxBioMed, Département des Sciences Biologiques Université du Québec à Montréal, Case Postale 8888, Succursale Centre-ville, Montréal, Quebec, Canada H3C 3P8Laboratoire du Métabolisme des LipoprotéinesBioMed, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Quebec, Canada H3C 3P8
| | - Louise Martin-Falstrault
- Laboratoire du Métabolisme OsseuxBioMed, Département des Sciences Biologiques Université du Québec à Montréal, Case Postale 8888, Succursale Centre-ville, Montréal, Quebec, Canada H3C 3P8Laboratoire du Métabolisme des LipoprotéinesBioMed, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Quebec, Canada H3C 3P8
| | - Louise Brissette
- Laboratoire du Métabolisme OsseuxBioMed, Département des Sciences Biologiques Université du Québec à Montréal, Case Postale 8888, Succursale Centre-ville, Montréal, Quebec, Canada H3C 3P8Laboratoire du Métabolisme des LipoprotéinesBioMed, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Quebec, Canada H3C 3P8
| | - Robert Moreau
- Laboratoire du Métabolisme OsseuxBioMed, Département des Sciences Biologiques Université du Québec à Montréal, Case Postale 8888, Succursale Centre-ville, Montréal, Quebec, Canada H3C 3P8Laboratoire du Métabolisme des LipoprotéinesBioMed, Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Quebec, Canada H3C 3P8
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Shen WJ, Hu J, Hu Z, Kraemer FB, Azhar S. Scavenger receptor class B type I (SR-BI): a versatile receptor with multiple functions and actions. Metabolism 2014; 63:875-86. [PMID: 24854385 PMCID: PMC8078058 DOI: 10.1016/j.metabol.2014.03.011] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 03/12/2014] [Accepted: 03/18/2014] [Indexed: 11/16/2022]
Abstract
Scavenger receptor class B type I (SR-BI), is a physiologically relevant HDL receptor that mediates selective uptake of lipoprotein (HDL)-derived cholesteryl ester (CE) in vitro and in vivo. Mammalian SR-BI is a 509-amino acid, ~82 kDa glycoprotein that contains N- and C-terminal cytoplasmic domains, two-transmembrane domains, as well as a large extracellular domain containing 5-6 cysteine residues and multiple sites for N-linked glycosylation. The size and structural characteristics of SR-BI, however, vary considerably among lower vertebrates and insects. Recently, significant progress has been made in understanding the molecular mechanisms involved in the posttranscriptional/posttranslational regulation of SR-BI in a tissue specific manner. The purpose of this review is to summarize the current body of knowledge about the events and molecules connected with the posttranscriptional/posttranslational regulation of SR-BI and to update the molecular and functional characteristics of the insect SR-BI orthologs.
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MESH Headings
- Animals
- Biological Transport
- Gene Expression Regulation
- Glycosylation
- Humans
- Insect Proteins/chemistry
- Insect Proteins/genetics
- Insect Proteins/metabolism
- Lipoproteins, HDL/chemistry
- Lipoproteins, HDL/genetics
- Lipoproteins, HDL/metabolism
- Liver/metabolism
- Organ Specificity
- Protein Conformation
- Protein Processing, Post-Translational
- Receptors, Lipoprotein/chemistry
- Receptors, Lipoprotein/genetics
- Receptors, Lipoprotein/metabolism
- Scavenger Receptors, Class B/chemistry
- Scavenger Receptors, Class B/genetics
- Scavenger Receptors, Class B/metabolism
- Species Specificity
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Affiliation(s)
- Wen-Jun Shen
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Jie Hu
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304
| | - Zhigang Hu
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Fredric B Kraemer
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Salman Azhar
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Gastroenterology and Hepatology, Stanford University, Stanford, California 94305.
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