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Fung KYY, Ho TWW, Xu Z, Neculai D, Beauchemin CAA, Lee WL, Fairn GD. Apolipoprotein A1 and high-density lipoprotein limit low-density lipoprotein transcytosis by binding SR-B1. J Lipid Res 2024; 65:100530. [PMID: 38479648 PMCID: PMC11004410 DOI: 10.1016/j.jlr.2024.100530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 02/27/2024] [Accepted: 02/29/2024] [Indexed: 04/09/2024] Open
Abstract
Atherosclerosis results from the deposition and oxidation of LDL and immune cell infiltration in the sub-arterial space leading to arterial occlusion. Studies have shown that transcytosis transports circulating LDL across endothelial cells lining blood vessels. LDL transcytosis is initiated by binding to either scavenger receptor B1 (SR-B1) or activin A receptor-like kinase 1 on the apical side of endothelial cells leading to its transit and release on the basolateral side. HDL is thought to partly protect individuals from atherosclerosis due to its ability to remove excess cholesterol and act as an antioxidant. Apolipoprotein A1 (APOA1), an HDL constituent, can bind to SR-B1, raising the possibility that APOA1/HDL can compete with LDL for SR-B1 binding, thereby limiting LDL deposition in the sub-arterial space. To examine this possibility, we used in vitro approaches to quantify the internalization and transcytosis of fluorescent LDL in coronary endothelial cells. Using microscale thermophoresis and affinity capture, we find that SR-B1 and APOA1 interact and that binding is enhanced when using the cardioprotective variant of APOA1 termed Milano (APOA1-Milano). In male mice, transiently increasing the levels of HDL reduced the acute deposition of fluorescently labeled LDL in the atheroprone inner curvature of the aorta. Reduced LDL deposition was also observed when increasing circulating wild-type APOA1 or the APOA1-Milano variant, with a more robust inhibition from the APOA1-Milano. The results suggest that HDL may limit SR-B1-mediated LDL transcytosis and deposition, adding to the mechanisms by which it can act as an atheroprotective particle.
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Affiliation(s)
- Karen Y Y Fung
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada
| | - Tse Wing Winnie Ho
- Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Zizhen Xu
- Department of Cell Biology, and Department of Pathology Sir Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Dante Neculai
- Department of Cell Biology, and Department of Pathology Sir Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Catherine A A Beauchemin
- Department of Physics, Toronto Metropolitan University, Toronto, Ontario, Canada; Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) program, RIKEN, Wako, Saitama, Japan
| | - Warren L Lee
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.
| | - Gregory D Fairn
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.
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2
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A Study on Multiple Facets of Apolipoprotein A1 Milano. Appl Biochem Biotechnol 2023:10.1007/s12010-023-04330-2. [PMID: 36689166 DOI: 10.1007/s12010-023-04330-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2023] [Indexed: 01/24/2023]
Abstract
For several strategies formulated to prevent atherosclerosis, Apolipoprotein A1 Milano (ApoA1M) remains a prime target. ApoA1M has been reported to have greater efficiency in reducing the incidence of coronary artery diseases. Furthermore, recombinant ApoA1M based mimetic peptide exhibits comparatively greater atheroprotective potential, offers a hope in reducing the burden of atherosclerosis in in vivo model system. The aim of this review is to emphasize on some of the observed ApoA1M structural and functional effects that are clinically and therapeutically meaningful that might converge on the basic role of ApoA1M in reducing the chances of glycation assisted ailments in diabetes. We also hypothesize that the nonenzymatic glycation prone arginine amino acid of ApoA1 gets replaced with cysteine residue and the rate of ApoA1 glycation may decrease due to change substitution of amino acid. Therefore, to circumvent the effect of ApoA1M glycation, the related mechanism should be explored at the cellular and functional levels, especially in respective experimental disease model in vivo.
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3
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Chen L, Zhao ZW, Zeng PH, Zhou YJ, Yin WJ. Molecular mechanisms for ABCA1-mediated cholesterol efflux. Cell Cycle 2022; 21:1121-1139. [PMID: 35192423 PMCID: PMC9103275 DOI: 10.1080/15384101.2022.2042777] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The maintenance of cellular cholesterol homeostasis is essential for normal cell function and viability. Excessive cholesterol accumulation is detrimental to cells and serves as the molecular basis of many diseases, such as atherosclerosis, Alzheimer's disease, and diabetes mellitus. The peripheral cells do not have the ability to degrade cholesterol. Cholesterol efflux is therefore the only pathway to eliminate excessive cholesterol from these cells. This process is predominantly mediated by ATP-binding cassette transporter A1 (ABCA1), an integral membrane protein. ABCA1 is known to transfer intracellular free cholesterol and phospholipids to apolipoprotein A-I (apoA-I) for generating nascent high-density lipoprotein (nHDL) particles. nHDL can accept more free cholesterol from peripheral cells. Free cholesterol is then converted to cholesteryl ester by lecithin:cholesterol acyltransferase to form mature HDL. HDL-bound cholesterol enters the liver for biliary secretion and fecal excretion. Although how cholesterol is transported by ABCA1 to apoA-I remains incompletely understood, nine models have been proposed to explain this effect. In this review, we focus on the current view of the mechanisms underlying ABCA1-mediated cholesterol efflux to provide an important framework for future investigation and lipid-lowering therapy.
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Affiliation(s)
- Lei Chen
- Department of Cardiology, The Second Affiliated Hospital of Hainan Medical University, Haikou, Hainan, China
| | - Zhen-Wang Zhao
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Peng-Hui Zeng
- Department of Clinical Laboratory, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Ying-Jie Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Wen-Jun Yin
- Department of Clinical Laboratory, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China,CONTACT Wen-Jun Yin Department of Clinical Laboratory, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan421001, China
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4
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Puppione DL, Tran DP, Zenaidee MA, Charugundla S, Whitelegge JP, Buffenstein R. Naked Mole-Rat, a Rodent with an Apolipoprotein A-I Dimer. Lipids 2020; 56:269-278. [PMID: 33336429 DOI: 10.1002/lipd.12286] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/11/2020] [Accepted: 09/14/2020] [Indexed: 01/28/2023]
Abstract
A variety of rodents have been used as experimental animals in metabolic studies of plasma lipids and lipoproteins. These studies have included understanding the functional role of apolipoprotein A-I, the major protein on the surface of HDL. Reviewing the genomic database for entries for rodent apoA-I genes, it was discovered that the naked mole-rat (Heterocephalus glaber) gene encoded a protein with a cysteine at residue 28. Previously, two cases have been reported in which human heterozygotes had apoA-I with cysteine at residues 173 (apoA-I Milano) or at 151 (apoA-I Paris). Interestingly, both groups, in spite of having low levels of HDL and moderately elevated plasma triacylglycerols, had no evidence of cardiovascular disease. Moreover, the presence of the cysteine enabled the apoA-I to form both homodimers and heterodimers. Prior to this report, no other mammalian apoA-I has been found with a cysteine in its sequence. In addition, the encoded naked mole-rat protein had different amino acids at sites that were conserved in all other mammals. These differences resulted in naked mole-rat apoA-I having an unexpected neutral pI value, whereas other mammalian apoA-I have negative pI values. To verify these sequence differences and to determine if the N-terminal location of C28 precluded dimer formation, we conducted mass spectrometry analyses of apoA-I and other proteins associated with HDL. Consistent with the genomic data, our analyses confirmed the presence of C28 and the formation of a homodimer. Analysis of plasma lipids surprisingly revealed a profile similar to the human heterozygotes.
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Affiliation(s)
- Don L Puppione
- The Molecular Biology Institute, Boyer Hall, Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Denise P Tran
- The Molecular Biology Institute, Boyer Hall, Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Muhammad A Zenaidee
- The Molecular Biology Institute, Boyer Hall, Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Sarada Charugundla
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Julian P Whitelegge
- The Pasarow Mass Spectrometry Laboratory, The Jane & Terry Semel Institute for Neuroscience and Human Behavior, Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Rochelle Buffenstein
- Barshop Institute for Aging and Longevity Studies and Department of Physiology, University of Texas Health Science Center San Antonio (UTHSCSA), San Antonio, TX, USA.,Calico Life Sciences LLC, 1170 Veterans Blvd, South San Francisco, CA, 94080, USA
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5
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Nilsson O, Lindvall M, Obici L, Ekström S, Lagerstedt JO, Del Giudice R. Structure dynamics of ApoA-I amyloidogenic variants in small HDL increase their ability to mediate cholesterol efflux. J Lipid Res 2020; 62:100004. [PMID: 33410751 PMCID: PMC7890215 DOI: 10.1194/jlr.ra120000920] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 01/17/2023] Open
Abstract
Apolipoprotein A-I (ApoA-I) of high density lipoproteins (HDLs) is essential for the transportation of cholesterol between peripheral tissues and the liver. However, specific mutations in ApoA-I of HDLs are responsible for a late-onset systemic amyloidosis, the pathological accumulation of protein fibrils in tissues and organs. Carriers of these mutations do not exhibit increased cardiovascular disease risk despite displaying reduced levels of ApoA-I/HDL cholesterol. To explain this paradox, we show that the HDL particle profiles of patients carrying either L75P or L174S ApoA-I amyloidogenic variants show a higher relative abundance of the 8.4-nm versus 9.6-nm particles and that serum from patients, as well as reconstituted 8.4- and 9.6-nm HDL particles (rHDL), possess increased capacity to catalyze cholesterol efflux from macrophages. Synchrotron radiation circular dichroism and hydrogen-deuterium exchange revealed that the variants in 8.4-nm rHDL have altered secondary structure composition and display a more flexible binding to lipids than their native counterpart. The reduced HDL cholesterol levels of patients carrying ApoA-I amyloidogenic variants are thus balanced by higher proportion of small, dense HDL particles, and better cholesterol efflux due to altered, region-specific protein structure dynamics.
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Affiliation(s)
- Oktawia Nilsson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Mikaela Lindvall
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Laura Obici
- Amyloidosis Research & Treatment Centre, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Simon Ekström
- BioMS - Swedish National Infrastructure for Biological Mass Spectrometry, Lund University, Lund, Sweden
| | - Jens O Lagerstedt
- Department of Experimental Medical Science, Lund University, Lund, Sweden; Lund Institute of Advanced Neutron and X-ray Science (LINXS), Lund, Sweden.
| | - Rita Del Giudice
- Department of Experimental Medical Science, Lund University, Lund, Sweden.
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6
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Low cholesterol syndrome and drug development. Curr Opin Cardiol 2020; 35:423-427. [PMID: 32452920 DOI: 10.1097/hco.0000000000000745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Low cholesterol syndromes were considered curiosities. The present article reviews some hypolipidaemic disorders and the drugs developed from the insights they provided. RECENT FINDINGS Abetalipopoproteinaemia and hypobetalipoproteinaemia are associated with low cholesterol concentrations and caused by mutations in apolipoprotein (apo) B or microsomal transfer protein. This led to the development of mipomersen and lomitapide which are used to treat homozygous familial hypercholesterolaemia. Mutations in proprotein convertase subtilisin kexin-9 (PCSK9) can cause either high or low cholesterol. Loss of function PCSK9 mutations prompted the development of antibody therapies to PCSK9 which are now widely used to treat hypercholesterolaemia. Mutations in apolipoprotein C-3 and angiopoietin-like protein 3 (ANGPTL3) cause hypolipoproteinaemia and reduced triglycerides. Antisense therapies to apolipoprotein C-3 and antibodies to ANGPTL3 are in development to treat familial chylomicronaemia syndrome. Activating mutations in apoA-1 result in hyper-functioning high-density lipoprotein (HDL) and suggest that modifying HDL turnover may reduce cardiovascular disease (CVD) risk. SUMMARY Orphan lipid disorders have provided insights into mechanisms involved in lowering cholesterol levels and the potential safety and efficacy of interventional processes. They have been not only enabled development of drugs to treat rare lipid disorders but also those finding wider use in general lowering of CVD risk.
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7
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Enkavi G, Javanainen M, Kulig W, Róg T, Vattulainen I. Multiscale Simulations of Biological Membranes: The Challenge To Understand Biological Phenomena in a Living Substance. Chem Rev 2019; 119:5607-5774. [PMID: 30859819 PMCID: PMC6727218 DOI: 10.1021/acs.chemrev.8b00538] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Indexed: 12/23/2022]
Abstract
Biological membranes are tricky to investigate. They are complex in terms of molecular composition and structure, functional over a wide range of time scales, and characterized by nonequilibrium conditions. Because of all of these features, simulations are a great technique to study biomembrane behavior. A significant part of the functional processes in biological membranes takes place at the molecular level; thus computer simulations are the method of choice to explore how their properties emerge from specific molecular features and how the interplay among the numerous molecules gives rise to function over spatial and time scales larger than the molecular ones. In this review, we focus on this broad theme. We discuss the current state-of-the-art of biomembrane simulations that, until now, have largely focused on a rather narrow picture of the complexity of the membranes. Given this, we also discuss the challenges that we should unravel in the foreseeable future. Numerous features such as the actin-cytoskeleton network, the glycocalyx network, and nonequilibrium transport under ATP-driven conditions have so far received very little attention; however, the potential of simulations to solve them would be exceptionally high. A major milestone for this research would be that one day we could say that computer simulations genuinely research biological membranes, not just lipid bilayers.
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Affiliation(s)
- Giray Enkavi
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Matti Javanainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy
of Sciences, Flemingovo naḿesti 542/2, 16610 Prague, Czech Republic
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Waldemar Kulig
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Tomasz Róg
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Ilpo Vattulainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
- MEMPHYS-Center
for Biomembrane Physics
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8
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Kosmas CE, Silverio D, Sourlas A, Garcia F, Montan PD, Guzman E. Primary genetic disorders affecting high density lipoprotein (HDL). Drugs Context 2018; 7:212546. [PMID: 30214464 PMCID: PMC6135231 DOI: 10.7573/dic.212546] [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: 06/17/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 01/21/2023] Open
Abstract
There is extensive evidence demonstrating that there is a clear inverse correlation between plasma high density lipoprotein cholesterol (HDL-C) concentration and cardiovascular disease (CVD). On the other hand, there is also extensive evidence that HDL functionality plays a very important role in atheroprotection. Thus, genetic disorders altering certain enzymes, lipid transfer proteins, or specific receptors crucial for the metabolism and adequate function of HDL, may positively or negatively affect the HDL-C levels and/or HDL functionality and subsequently either provide protection or predispose to atherosclerotic disease. This review aims to describe certain genetic disorders associated with either low or high plasma HDL-C and discuss their clinical features, associated risk for cardiovascular events, and treatment options.
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Affiliation(s)
- Constantine E Kosmas
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, New York, NY, USA
| | - Delia Silverio
- Cardiology Clinic, Cardiology Unlimited, PC, New York, NY, USA
| | | | - Frank Garcia
- Cardiology Clinic, Cardiology Unlimited, PC, New York, NY, USA
| | - Peter D Montan
- Cardiology Clinic, Cardiology Unlimited, PC, New York, NY, USA
| | - Eliscer Guzman
- Division of Cardiology, Department of Medicine, Montefiore Medical Center, Bronx, NY, USA
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9
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Gorshkova IN, Mei X, Atkinson D. Arginine 123 of apolipoprotein A-I is essential for lecithin:cholesterol acyltransferase activity. J Lipid Res 2017; 59:348-356. [PMID: 29208698 DOI: 10.1194/jlr.m080986] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/29/2017] [Indexed: 01/10/2023] Open
Abstract
ApoA-I activates LCAT that converts lipoprotein cholesterol to cholesteryl ester (CE). Molecular dynamic simulations suggested earlier that helices 5 of two antiparallel apoA-I molecules on discoidal HDL form an amphipathic tunnel for migration of acyl chains and unesterified cholesterol to the active sites of LCAT. Our recent crystal structure of Δ(185-243)apoA-I showed the tunnel formed by helices 5/5, with two positively charged residues arginine 123 positioned at the edge of the hydrophobic tunnel. We hypothesized that these uniquely positioned residues Arg123 are poised for interaction with fatty acids produced by LCAT hydrolysis of the sn-2 chains of phosphatidylcholine, thus positioning the fatty acids for esterification to cholesterol. To test the importance of Arg123 for LCAT phospholipid hydrolysis and CE formation, we generated apoA-I[R123A] and apoA-I[R123E] mutants and made discoidal HDL with the mutants and WT apoA-I. Neither mutation of Arg123 changed the particle composition or size, or the protein conformation or stability. However, both mutations of Arg123 significantly reduced LCAT catalytic efficiency and the apparent Vmax for CE formation without affecting LCAT phospholipid hydrolysis. A control mutation, apoA-I[R131A], did not affect LCAT phospholipid hydrolysis or CE formation. These data suggest that Arg123 of apoA-I on discoidal HDL participates in LCAT-mediated cholesterol esterification.
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Affiliation(s)
- Irina N Gorshkova
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Xiaohu Mei
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - David Atkinson
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
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10
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Effect of lipid-bound apolipoprotein A-I cysteine mutant on ATF3 in RAW264.7 cells. Biosci Rep 2017; 37:BSR20160398. [PMID: 28093456 PMCID: PMC5291141 DOI: 10.1042/bsr20160398] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 12/25/2016] [Accepted: 01/16/2017] [Indexed: 12/02/2022] Open
Abstract
Activating transcription factor 3 (ATF3) is a TLR-induced repressor that plays an important role in the inhibition of specific inflammatory signals. We previously constructed recombinant high density lipoproteins (rHDL) (including rHDLWT, rHDLM, rHDL228 and rHDL74) and found that rHDL74 had a strong anti-inflammatory ability. In the present study, we investigate the roles of recombinant apolipoprotein A-I (ApoA-I) (rHDLWT) and its cysteine mutant HDLs (rHDLM, rHDL228 and rHDL74) on ATF3 function in RAW264.7 cells stimulated by lipopolysaccharide. Our results showed that compared with the LPS group, rHDL74 can decrease the level of TNF-α and IL-6, whereas rHDL228 increases their expression levels. RT-PCR and Western blotting results showed that compared with the LPS group, rHDL74, rHDLWT and rHDLM can markedly increase the expression level of ATF3, whereas the level of ATF3 decreases in the rHDL228 group. In summary, the different anti-inflammatory mechanisms of the ApoA-I cysteine mutants might be associated with the regulation of ATF3 level.
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11
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Mo ZC, Ren K, Liu X, Tang ZL, Yi GH. A high-density lipoprotein-mediated drug delivery system. Adv Drug Deliv Rev 2016; 106:132-147. [PMID: 27208399 DOI: 10.1016/j.addr.2016.04.030] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/13/2016] [Accepted: 04/27/2016] [Indexed: 01/08/2023]
Abstract
High-density lipoprotein (HDL) is a comparatively dense and small lipoprotein that can carry lipids as a multifunctional aggregate in plasma. Several studies have shown that increasing the levels or improving the functionality of HDL is a promising target for treating a wide variety of diseases. Among lipoproteins, HDL particles possess unique physicochemical properties, including naturally synthesized physiological components, amphipathic apolipoproteins, lipid-loading and hydrophobic agent-incorporating characteristics, specific protein-protein interactions, heterogeneity, nanoparticles, and smaller size. Recently, the feasibility and superiority of using HDL particles as drug delivery vehicles have been of great interest. In this review, we summarize the structure, constituents, biogenesis, remodeling, and reconstitution of HDL drug delivery systems, focusing on their delivery capability, characteristics, applications, manufacturing, and drug-loading and drug-targeting characteristics. Finally, the future prospects are presented regarding the clinical application and challenges of using HDL as a pharmacodelivery carrier.
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Affiliation(s)
- Zhong-Cheng Mo
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City 421001, Hunan Province, China; Department of Histology and Embryology, University of South China, Hengyang, Hunan 421001, China
| | - Kun Ren
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City 421001, Hunan Province, China
| | - Xing Liu
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 100005 Beijing, China
| | - Zhen-Li Tang
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City 421001, Hunan Province, China
| | - Guang-Hui Yi
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City 421001, Hunan Province, China.
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12
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Gulshan K, Brubaker G, Conger H, Wang S, Zhang R, Hazen SL, Smith JD. PI(4,5)P2 Is Translocated by ABCA1 to the Cell Surface Where It Mediates Apolipoprotein A1 Binding and Nascent HDL Assembly. Circ Res 2016; 119:827-38. [PMID: 27514935 DOI: 10.1161/circresaha.116.308856] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 08/11/2016] [Indexed: 12/23/2022]
Abstract
RATIONALE The molecular mechanism by which ATP-binding cassette transporter A1 (ABCA1) mediates cellular binding of apolipoprotein A-I (apoA1) and nascent high-density lipoprotein (HDL) assembly is not well understood. OBJECTIVE To determine the cell surface lipid that mediates apoA1 binding to ABCA1-expressing cells and the role it plays in nascent HDL assembly. METHODS AND RESULTS Using multiple biochemical and biophysical methods, we found that apoA1 binds specifically to phosphatidylinositol (4,5) bis-phosphate (PIP2). Flow cytometry and PIP2 reporter-binding assays demonstrated that ABCA1 led to PIP2 redistribution from the inner to the outer leaflet of the plasma membrane. Enzymatic cleavage of cell surface PIP2 or decreased cellular PIP2 by knockdown of phosphatidylinositol-5-phosphate 4-kinase impaired apoA1 binding and cholesterol efflux to apoA1. PIP2 also increased the spontaneous solubilization of phospholipid liposomes by apoA1. Using site-directed mutagenesis, we found that ABCA1's PIP2 and phosphatidylserine translocase activities are independent from each other. Furthermore, we discovered that PIP2 is effluxed from cells to apoA1, where it is associated with HDL in plasma, and that PIP2 on HDL is taken up by target cells in a scavenger receptor-BI-dependent manner. Mouse plasma PIP2 levels are apoA1 gene dosage-dependent and are >1 μM in apoA1 transgenic mice. CONCLUSIONS ABCA1 has PIP2 floppase activity, which increases cell surface PIP2 levels that mediate apoA1 binding and lipid efflux during nascent HDL assembly. We found that PIP2 itself is effluxed to apoA1 and it circulates on plasma HDL, where it can be taken up via the HDL receptor scavenger receptor-BI.
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Affiliation(s)
- Kailash Gulshan
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH.
| | - Gregory Brubaker
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH
| | - Heather Conger
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH
| | - Shuhui Wang
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH
| | - Renliang Zhang
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH
| | - Stanley L Hazen
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH
| | - Jonathan D Smith
- From the Department of Cellular and Molecular Medicine (K.G., G.B., H.C., S.W., R.Z., S.L.H., J.D.S.) and Department of Cardiovascular Medicine (S.L.H., J.D.S.), Cleveland Clinic, OH.
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13
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Della Torre S, Mitro N, Fontana R, Gomaraschi M, Favari E, Recordati C, Lolli F, Quagliarini F, Meda C, Ohlsson C, Crestani M, Uhlenhaut NH, Calabresi L, Maggi A. An Essential Role for Liver ERα in Coupling Hepatic Metabolism to the Reproductive Cycle. Cell Rep 2016; 15:360-71. [PMID: 27050513 PMCID: PMC4835581 DOI: 10.1016/j.celrep.2016.03.019] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 12/21/2015] [Accepted: 03/02/2016] [Indexed: 12/27/2022] Open
Abstract
Lipoprotein synthesis is controlled by estrogens, but the exact mechanisms underpinning this regulation and the role of the hepatic estrogen receptor α (ERα) in cholesterol physiology are unclear. Utilizing a mouse model involving selective ablation of ERα in the liver, we demonstrate that hepatic ERα couples lipid metabolism to the reproductive cycle. We show that this receptor regulates the synthesis of cholesterol transport proteins, enzymes for lipoprotein remodeling, and receptors for cholesterol uptake. Additionally, ERα is indispensable during proestrus for the generation of high-density lipoproteins efficient in eliciting cholesterol efflux from macrophages. We propose that a specific interaction with liver X receptor α (LXRα) mediates the broad effects of ERα on the hepatic lipid metabolism.
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Affiliation(s)
- Sara Della Torre
- Center of Excellence on Neurodegenerative Diseases, University of Milan, 20133 Milan, Italy; Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Nico Mitro
- Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Roberta Fontana
- Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy; Department of Drug Discovery and Development, Italian Institute of Technology, 16163 Genova, Italy
| | - Monica Gomaraschi
- Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Elda Favari
- Department of Pharmacy, University of Parma, 43121 Parma, Italy
| | - Camilla Recordati
- Mouse and Animal Pathology Laboratory, Fondazione Filarete, 20139 Milan, Italy
| | - Federica Lolli
- Center of Excellence on Neurodegenerative Diseases, University of Milan, 20133 Milan, Italy; Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Fabiana Quagliarini
- Helmholtz Diabetes Center (HDC) and German Center for Diabetes Research (DZD), Helmholtz Zentrum Muenchen, 85764 Munich-Neuherberg, Germany
| | - Clara Meda
- Center of Excellence on Neurodegenerative Diseases, University of Milan, 20133 Milan, Italy; Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Claes Ohlsson
- Centre for Bone and Arthritis Research and Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden
| | - Maurizio Crestani
- Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Nina Henriette Uhlenhaut
- Helmholtz Diabetes Center (HDC) and German Center for Diabetes Research (DZD), Helmholtz Zentrum Muenchen, 85764 Munich-Neuherberg, Germany
| | - Laura Calabresi
- Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | - Adriana Maggi
- Center of Excellence on Neurodegenerative Diseases, University of Milan, 20133 Milan, Italy; Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy.
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14
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Update on the molecular biology of dyslipidemias. Clin Chim Acta 2016; 454:143-85. [DOI: 10.1016/j.cca.2015.10.033] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/24/2015] [Accepted: 10/30/2015] [Indexed: 12/20/2022]
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15
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Huang LH, Elvington A, Randolph GJ. The role of the lymphatic system in cholesterol transport. Front Pharmacol 2015; 6:182. [PMID: 26388772 PMCID: PMC4557107 DOI: 10.3389/fphar.2015.00182] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/12/2015] [Indexed: 11/13/2022] Open
Abstract
Reverse cholesterol transport (RCT) is the pathway for removal of peripheral tissue cholesterol and involves transport of cholesterol back to liver for excretion, starting from cellular cholesterol efflux facilitated by lipid-free apolipoprotein A1 (ApoA1) or other lipidated high-density lipoprotein (HDL) particles within the interstitial space. Extracellular cholesterol then is picked up and transported through the lymphatic vasculature before entering into bloodstream. There is increasing evidence supporting a role for enhanced macrophage cholesterol efflux and RCT in ameliorating atherosclerosis, and recent data suggest that these processes may serve as better diagnostic biomarkers than plasma HDL levels. Hence, it is important to better understand the processes governing ApoA1 and HDL influx into peripheral tissues from the bloodstream, modification and facilitation of cellular cholesterol removal within the interstitial space, and transport through the lymphatic vasculature. New findings will complement therapeutic strategies for the treatment of atherosclerotic vascular disease.
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Affiliation(s)
- Li-Hao Huang
- Department of Pathology and Immunology, Washington University School of Medicine , St. Louis, MO, USA
| | - Andrew Elvington
- Department of Pathology and Immunology, Washington University School of Medicine , St. Louis, MO, USA
| | - Gwendalyn J Randolph
- Department of Pathology and Immunology, Washington University School of Medicine , St. Louis, MO, USA
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16
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Mei X, Atkinson D. Lipid-free Apolipoprotein A-I Structure: Insights into HDL Formation and Atherosclerosis Development. Arch Med Res 2015; 46:351-60. [PMID: 26048453 DOI: 10.1016/j.arcmed.2015.05.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 05/27/2015] [Indexed: 12/22/2022]
Abstract
Apolipoprotein A-I is the major protein in high-density lipoprotein (HDL) and plays an important role during the process of reverse cholesterol transport (RCT). Knowledge of the high-resolution structure of full-length apoA-I is vital for a molecular understanding of the function of HDL at the various steps of the RCT pathway. Due to the flexible nature of apoA-I and aggregation properties, the structure of full-length lipid-free apoA-I has evaded description for over three decades. Sequence analysis of apoA-I suggested that the amphipathic α-helix is the structural motif of exchangeable apolipoprotein, and NMR, X-ray and MD simulation studies have confirmed this. Different laboratories have used different methods to probe the secondary structure distribution and organization of both the lipid-free and lipid-bound apoA-I structure. Mutation analysis, synthetic peptide models, surface chemistry and crystal structures have converged on the lipid-free apoA-I domain structure and function: the N-terminal domain [1-184] forms a helix bundle while the C-terminal domain [185-243] mostly lacks defined structure and is responsible for initiating lipid-binding, aggregation and is also involved in cholesterol efflux. The first 43 residues of apoA-I are essential to stabilize the lipid-free structure. In addition, the crystal structure of C-terminally truncated apoA-I suggests a monomer-dimer conversation mechanism mediated through helix 5 reorganization and dimerization during the formation of HDL. Based on previous research, we have proposed a structural model for full-length monomeric apoA-I in solution and updated the HDL formation mechanism through three states. Mapping the known natural mutations on the full-length monomeric apoA-I model provides insight into atherosclerosis development through disruption of the N-terminal helix bundle or deletion of the C-terminal lipid-binding domain.
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Affiliation(s)
- Xiaohu Mei
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts, USA
| | - David Atkinson
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts, USA.
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17
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Structural stability and functional remodeling of high-density lipoproteins. FEBS Lett 2015; 589:2627-39. [PMID: 25749369 DOI: 10.1016/j.febslet.2015.02.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 02/16/2015] [Accepted: 02/23/2015] [Indexed: 12/28/2022]
Abstract
Lipoproteins are protein-lipid nanoparticles that transport lipids in circulation and are central in atherosclerosis and other disorders of lipid metabolism. Apolipoproteins form flexible structural scaffolds and important functional ligands on the particle surface and direct lipoprotein metabolism. Lipoproteins undergo multiple rounds of metabolic remodeling that is crucial to lipid transport. Important aspects of this remodeling, including apolipoprotein dissociation and particle fusion, are mimicked in thermal or chemical denaturation and are modulated by free energy barriers. Here we review the biophysical studies that revealed the kinetic mechanism of lipoprotein stabilization and unraveled its structural basis. The main focus is on high-density lipoprotein (HDL). An inverse correlation between stability and functions of various HDLs in cholesterol transport suggests the functional role of structural disorder. A mechanism for the conformational adaptation of the major HDL proteins, apoA-I and apoA-II, to the increasing lipid load is proposed. Together, these studies help understand why HDL forms discrete subclasses separated by kinetic barriers, which have distinct composition, conformation and functional properties. Understanding these properties may help improve HDL quality and develop novel therapies for cardiovascular disease.
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18
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Niesor EJ. Will Lipidation of ApoA1 through Interaction with ABCA1 at the Intestinal Level Affect the Protective Functions of HDL? BIOLOGY 2015; 4:17-38. [PMID: 25569858 PMCID: PMC4381214 DOI: 10.3390/biology4010017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 12/18/2014] [Indexed: 11/16/2022]
Abstract
The relationship between levels of high-density lipoprotein cholesterol (HDL-C) and cardiovascular (CV) risk is well recognized; however, in recent years, large-scale phase III studies with HDL-C-raising or -mimicking agents have failed to demonstrate a clinical benefit on CV outcomes associated with raising HDL-C, casting doubt on the "HDL hypothesis." This article reviews potential reasons for the observed negative findings with these pharmaceutical compounds, focusing on the paucity of translational models and relevant biomarkers related to HDL metabolism that may have confounded understanding of in vivo mechanisms. A unique function of HDL is its ability to interact with the ATP-binding cassette transporter (ABC) A1 via apolipoprotein (Apo) A1. Only recently, studies have shown that this process may be involved in the intestinal uptake of dietary sterols and antioxidants (vitamin E, lutein and zeaxanthin) at the basolateral surface of enterocytes. This parameter should be assessed for HDL-raising drugs in addition to the more documented reverse cholesterol transport (RCT) from peripheral tissues to the liver. Indeed, a single mechanism involving the same interaction between ApoA1 and ABCA1 may encompass two HDL functions previously considered as separate: antioxidant through the intestinal uptake of antioxidants and RCT through cholesterol efflux from loaded cells such as macrophages.
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Affiliation(s)
- Eric J Niesor
- F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, CH-4070 Basel, Switzerland.
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19
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Kontush A, Lindahl M, Lhomme M, Calabresi L, Chapman MJ, Davidson WS. Structure of HDL: particle subclasses and molecular components. Handb Exp Pharmacol 2015; 224:3-51. [PMID: 25522985 DOI: 10.1007/978-3-319-09665-0_1] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
A molecular understanding of high-density lipoprotein (HDL) will allow a more complete grasp of its interactions with key plasma remodelling factors and with cell-surface proteins that mediate HDL assembly and clearance. However, these particles are notoriously heterogeneous in terms of almost every physical, chemical and biological property. Furthermore, HDL particles have not lent themselves to high-resolution structural study through mainstream techniques like nuclear magnetic resonance and X-ray crystallography; investigators have therefore had to use a series of lower resolution methods to derive a general structural understanding of these enigmatic particles. This chapter reviews current knowledge of the composition, structure and heterogeneity of human plasma HDL. The multifaceted composition of the HDL proteome, the multiple major protein isoforms involving translational and posttranslational modifications, the rapidly expanding knowledge of the HDL lipidome, the highly complex world of HDL subclasses and putative models of HDL particle structure are extensively discussed. A brief history of structural studies of both plasma-derived and recombinant forms of HDL is presented with a focus on detailed structural models that have been derived from a range of techniques spanning mass spectrometry to molecular dynamics.
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Affiliation(s)
- Anatol Kontush
- National Institute for Health and Medical Research (INSERM), UMR-ICAN 1166, Paris, France,
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