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Cisse A, Desfosses A, Stainer S, Kandiah E, Traore DAK, Bezault A, Schachner-Nedherer AL, Leitinger G, Hoerl G, Hinterdorfer P, Gutsche I, Prassl R, Peters J, Kornmueller K. Targeting structural flexibility in low density lipoprotein by integrating cryo-electron microscopy and high-speed atomic force microscopy. Int J Biol Macromol 2023; 252:126345. [PMID: 37619685 DOI: 10.1016/j.ijbiomac.2023.126345] [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: 05/11/2023] [Revised: 08/08/2023] [Accepted: 08/13/2023] [Indexed: 08/26/2023]
Abstract
Low-density lipoprotein (LDL) plays a crucial role in cholesterol metabolism. Responsible for cholesterol transport from the liver to the organs, LDL accumulation in the arteries is a primary cause of cardiovascular diseases, such as atherosclerosis. This work focuses on the fundamental question of the LDL molecular structure, as well as the topology and molecular motions of apolipoprotein B-100 (apo B-100), which is addressed by single-particle cryo-electron microscopy (cryo-EM) and high-speed atomic force microscopy (HS-AFM). Our results suggest a revised model of the LDL core organization with respect to the cholesterol ester (CE) arrangement. In addition, a high-density region close to the flattened poles could be identified, likely enriched in free cholesterol. The most remarkable new details are two protrusions on the LDL surface, attributed to the protein apo B-100. HS-AFM adds the dimension of time and reveals for the first time a highly dynamic direct description of LDL, where we could follow large domain fluctuations of the protrusions in real time. To tackle the inherent flexibility and heterogeneity of LDL, the cryo-EM maps are further assessed by 3D variability analysis. Our study gives a detailed explanation how to approach the intrinsic flexibility of a complex system comprising lipids and protein.
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Affiliation(s)
- Aline Cisse
- Université Grenoble Alpes, CNRS, LiPhy, Grenoble, France; Institut Laue-Langevin, Grenoble, France
| | - Ambroise Desfosses
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Sarah Stainer
- Department of Experimental Applied Biophysics, Johannes Kepler University Linz, Linz, Austria
| | | | - Daouda A K Traore
- Institut Laue-Langevin, Grenoble, France; Faculté de Pharmacie, Université des Sciences, des Techniques et des Technologies de Bamako (USTTB), Bamako, Mali; Faculty of Natural Sciences, School of Life Sciences, Keele University, Staffordshire, UK
| | - Armel Bezault
- Institut Européen de Chimie et Biologie, UAR3033/US001, Université de Bordeaux, CNRS, INSERM 2, Pessac, France; Structural Image Analysis Unit, Department of Structural Biology and Chemistry, Institut Pasteur, Université Paris Cité, CNRS UMR3528, Paris, France
| | - Anna-Laurence Schachner-Nedherer
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Medical Physics and Biophysics Division, Medical University of Graz, Graz, Austria
| | - Gerd Leitinger
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Division of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Gerd Hoerl
- Otto Loewi Research Center, Physiological Chemistry, Medical University of Graz, Graz, Austria
| | - Peter Hinterdorfer
- Department of Experimental Applied Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Irina Gutsche
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Ruth Prassl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Medical Physics and Biophysics Division, Medical University of Graz, Graz, Austria
| | - Judith Peters
- Université Grenoble Alpes, CNRS, LiPhy, Grenoble, France; Institut Laue-Langevin, Grenoble, France; Institut Universitaire de France, France.
| | - Karin Kornmueller
- Institut Laue-Langevin, Grenoble, France; Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Medical Physics and Biophysics Division, Medical University of Graz, Graz, Austria.
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2
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Cholesterol Efflux Efficiency of Reconstituted HDL Is Affected by Nanoparticle Lipid Composition. Biomedicines 2020; 8:biomedicines8100373. [PMID: 32977626 PMCID: PMC7598155 DOI: 10.3390/biomedicines8100373] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/17/2020] [Accepted: 09/21/2020] [Indexed: 12/31/2022] Open
Abstract
Cardiovascular disease (CVD), the leading cause of mortality worldwide is primarily caused by atherosclerosis, which is promoted by the accumulation of low-density lipoproteins into the intima of large arteries. Multiple nanoparticles mimicking natural HDL (rHDL) have been designed to remove cholesterol excess in CVD therapy. The goal of this investigation was to assess the cholesterol efflux efficiency of rHDLs with different lipid compositions, mimicking different maturation stages of high-density lipoproteins (HDLs) occurring in vivo. Methods: the cholesterol efflux activity of soybean PC (Soy-PC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), DPPC:Chol:1-palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine (LysoPC) and DPPC:18:2 cholesteryl ester (CE):LysoPC rHDLs was determined in several cell models to investigate the contribution of lipid composition to the effectiveness of cholesterol removal. Results: DPPC rHDLs are the most efficient particles, inducing cholesterol efflux in all cellular models and in all conditions the effect was potentiated when the ABCA1 transporter was upregulated. Conclusions: DPPC rHDLs, which resemble nascent HDL, are the most effective particles in inducing cholesterol efflux due to the higher physical binding affinity of cholesterol to the saturated long-chain-length phospholipids and the favored cholesterol transfer from a highly positively curved bilayer, to an accepting planar bilayer such as DPPC rHDLs. The physicochemical characteristics of rHDLs should be taken into consideration to design more efficient nanoparticles to promote cholesterol efflux.
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Baumstark D, Kremer W, Boettcher A, Schreier C, Sander P, Schmitz G, Kirchhoefer R, Huber F, Kalbitzer HR. 1H NMR spectroscopy quantifies visibility of lipoproteins, subclasses, and lipids at varied temperatures and pressures. J Lipid Res 2019; 60:1516-1534. [PMID: 31239285 PMCID: PMC6718440 DOI: 10.1194/jlr.m092643] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 06/18/2019] [Indexed: 01/27/2023] Open
Abstract
NMR-based quantification of human lipoprotein (sub)classes is a powerful high-throughput method for medical diagnostics. We evaluated select proton NMR signals of serum lipoproteins for elucidating the physicochemical features and the absolute NMR visibility of their lipids. We separated human lipoproteins of different subclasses by ultracentrifugation and analyzed them by 1H NMR spectroscopy at different temperatures (283-323 K) and pressures (0.1-200 MPa). In parallel, we determined the total lipid content by extraction with chloroform/methanol. The visibility of different lipids in the 1H NMR spectra strongly depends on temperature and pressure: it increases with increasing temperatures but decreases with increasing pressures. Even at 313 K, only part of the lipoprotein is detected quantitatively. In LDL and in HDL subclasses HDL2 and HDL3, only 39%, 62%, and 90% of the total cholesterol and only 73%, 70%, and 87% of the FAs are detected, respectively. The choline head groups show visibilities of 43%, 75%, and 87% for LDL, HDL2, and HDL3, respectively. The description of the NMR visibility of lipid signals requires a minimum model of three different compartments, A, B, and C. The thermodynamic analysis of compartment B leads to melting temperatures between 282 K and 308 K and to enthalpy differences that vary for the different lipoproteins as well as for the reporter groups selected. In summary, we describe differences in NMR visibility of lipoproteins and variations in biophysical responses of functional groups that are crucial for the accuracy of absolute NMR quantification.
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Affiliation(s)
- Daniela Baumstark
- Institute of Biophysics and Physical BiochemistryUniversity of Regensburg, 93040 Regensburg, Germany; Centre of Magnetic Resonance in Chemistry and Biomedicine University of Regensburg, 93040 Regensburg, Germany
| | - Werner Kremer
- Institute of Biophysics and Physical BiochemistryUniversity of Regensburg, 93040 Regensburg, Germany; Centre of Magnetic Resonance in Chemistry and Biomedicine University of Regensburg, 93040 Regensburg, Germany
| | - Alfred Boettcher
- Institute of Clinical Chemistry and Laboratory Medicine University Hospital Regensburg, 93053 Regensburg, Germany
| | - Christina Schreier
- Institute of Biophysics and Physical BiochemistryUniversity of Regensburg, 93040 Regensburg, Germany; Centre of Magnetic Resonance in Chemistry and Biomedicine University of Regensburg, 93040 Regensburg, Germany; numares AG, 93053 Regensburg, Germany
| | - Paul Sander
- Institute of Biophysics and Physical BiochemistryUniversity of Regensburg, 93040 Regensburg, Germany; Centre of Magnetic Resonance in Chemistry and Biomedicine University of Regensburg, 93040 Regensburg, Germany
| | - Gerd Schmitz
- Institute of Clinical Chemistry and Laboratory Medicine University Hospital Regensburg, 93053 Regensburg, Germany
| | | | | | - Hans Robert Kalbitzer
- Institute of Biophysics and Physical BiochemistryUniversity of Regensburg, 93040 Regensburg, Germany; Centre of Magnetic Resonance in Chemistry and Biomedicine University of Regensburg, 93040 Regensburg, Germany.
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4
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Lei D, Yu Y, Kuang YL, Liu J, Krauss RM, Ren G. Single-molecule 3D imaging of human plasma intermediate-density lipoproteins reveals a polyhedral structure. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:260-270. [PMID: 30557627 PMCID: PMC6409128 DOI: 10.1016/j.bbalip.2018.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 11/25/2018] [Accepted: 12/09/2018] [Indexed: 11/25/2022]
Abstract
Intermediate-density lipoproteins (IDLs), the remnants of very-low-density lipoproteins via lipolysis, are rich in cholesteryl ester and are associated with cardiovascular disease. Despite pharmacological interest in IDLs, their three-dimensional (3D) structure is still undetermined due to their variation in size, composition, and dynamic structure. To explore the 3D structure of IDLs, we reconstructed 3D density maps from individual IDL particles using cryo-electron microscopy (cryo-EM) and individual-particle electron tomography (IPET, without averaging from different molecules). 3D reconstructions of IDLs revealed an unexpected polyhedral structure that deviates from the generally assumed spherical shape model (Frias et al., 2007; Olson, 1998; Shen et al., 1977). The polyhedral-shaped IDL contains a high-density shell formed by flat surfaces that are similar to those of very-low-density lipoproteins but have sharper dihedral angles between nearby surfaces. These flat surfaces would be less hydrophobic than the curved surface of mature spherical high-density lipoprotein (HDL), leading to a lower binding affinity of IDL to hydrophobic proteins (such as cholesteryl ester transfer protein) than HDL. This is the first visualization of the IDL 3D structure, which could provide fundamental clues for delineating the role of IDL in lipid metabolism and cardiovascular disease.
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Affiliation(s)
- Dongsheng Lei
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yadong Yu
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yu-Lin Kuang
- Atherosclerosis Research, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Jianfang Liu
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ronald M Krauss
- Atherosclerosis Research, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Gang Ren
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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5
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Lehofer B, Golub M, Kornmueller K, Kriechbaum M, Martinez N, Nagy G, Kohlbrecher J, Amenitsch H, Peters J, Prassl R. High Hydrostatic Pressure Induces a Lipid Phase Transition and Molecular Rearrangements in Low-Density Lipoprotein Nanoparticles. PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION : MEASUREMENT AND DESCRIPTION OF PARTICLE PROPERTIES AND BEHAVIOR IN POWDERS AND OTHER DISPERSE SYSTEMS 2018; 35:1800149. [PMID: 30283212 PMCID: PMC6166783 DOI: 10.1002/ppsc.201800149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Indexed: 06/08/2023]
Abstract
Low-density lipoproteins (LDL) are natural lipid transporter in human plasma whose chemically modified forms contribute to the progression of atherosclerosis and cardiovascular diseases accounting for a vast majority of deaths in westernized civilizations. For the development of new treatment strategies, it is important to have a detailed picture of LDL nanoparticles on a molecular basis. Through the combination of X-ray and neutron small-angle scattering (SAS) techniques with high hydrostatic pressure (HHP) this study describes structural features of normolipidemic, triglyceride-rich and oxidized forms of LDL. Due to the different scattering contrasts for X-rays and neutrons, information on the effects of HHP on the internal structure determined by lipid rearrangements and changes in particle shape becomes accessible. Independent pressure and temperature variations provoke a phase transition in the lipid core domain. With increasing pressure an inter-related anisotropic deformation and flattening of the particle are induced. All LDL nanoparticles maintain their structural integrity even at 3000 bar and show a reversible response toward pressure variations. The present work depicts the complementarity of pressure and temperature as independent thermodynamic parameters and introduces HHP as a tool to study molecular assembling and interaction processes in distinct lipoprotein particles in a nondestructive manner.
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Affiliation(s)
- Bernhard Lehofer
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/IV, 8010 Graz, Austria
| | - Maksym Golub
- Institut Laue-Langevin, 71 avenue des Martyrs, 38044 Grenoble, France; Univ. Grenoble Alpes, CNRS + CEA, IBS, 38000 Grenoble, France
| | - Karin Kornmueller
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/IV, 8010 Graz, Austria
| | - Manfred Kriechbaum
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Nicolas Martinez
- Institut Laue-Langevin, 71 avenue des Martyrs, 38044 Grenoble, France; Univ. Grenoble Alpes, CNRS + CEA, IBS, 38000 Grenoble, France
| | - Gergely Nagy
- Paul Scherrer Institut, 5232 Villigen, Switzerland; Wigner Research Centre for Physics, 1121 Budapest, Hungary; European Spallation Source ERIC, 22363 Lund, Sweden
| | | | - Heinz Amenitsch
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Judith Peters
- Institut Laue-Langevin, 71 avenue des Martyrs, 38044 Grenoble, France; Univ. Grenoble Alpes, CNRS, LiPhy, 38000 Grenoble, France
| | - Ruth Prassl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging Biophysics, Medical University of Graz, Neue Stiftingtalstraße 6/IV, 8010 Graz, Austria
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6
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Peters J, Martinez N, Lehofer B, Prassl R. Low-density lipoproteins investigated under high hydrostatic pressure by elastic incoherent neutron scattering. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2017; 40:68. [PMID: 28733727 PMCID: PMC5589066 DOI: 10.1140/epje/i2017-11558-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/11/2017] [Indexed: 05/14/2023]
Abstract
Human low-density lipoprotein (LDL) is a highly complex nano-particle built up of various lipid classes and a single large protein moiety (apoB-100) owning essential physiological functions in the human body. Besides its vital role as a supplier of cholesterol and fat for peripheral tissues and cells, it is also a known key player in the formation of atherosclerosis. Due to these important roles in physiology and pathology the elucidation of structural and dynamical details is of great interest. In the current study we drew a broader picture of LDL dynamics using elastic incoherent neutron scattering (EINS) as a function of specified temperature and pressure points. We not only investigated a normolipidemic LDL sample, but also a triglyceride-rich and an oxidized one to mimic pathologic conditions as found under hyperlipidemic conditions or in atherosclerotic plaques, respectively. We could show that pressure has a significant effect on atomic motions in modified forms of LDL, whereas the normolipidemic sample seems to cope much better with high-pressure conditions irrespective of temperature. These findings might be explained by the altered lipid composition, which is either caused through elevated triglyceride content or modifications through lipid peroxidation.
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Affiliation(s)
- J Peters
- Univ. Grenoble Alpes, LiPhy, F-38044, Grenoble, France
- Institut Laue Langevin, F-38000, Grenoble, France
| | - N Martinez
- Institut Laue Langevin, F-38000, Grenoble, France
- Univ. Grenoble Alpes, IBS, F-38000, Grenoble, France
| | - B Lehofer
- Institute of Biophysics, Medical University of Graz, A-8010, Graz, Austria
| | - R Prassl
- Institute of Biophysics, Medical University of Graz, A-8010, Graz, Austria.
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7
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Maric S, Lind TK, Lyngsø J, Cárdenas M, Pedersen JS. Modeling Small-Angle X-ray Scattering Data for Low-Density Lipoproteins: Insights into the Fatty Core Packing and Phase Transition. ACS NANO 2017; 11:1080-1090. [PMID: 28048943 DOI: 10.1021/acsnano.6b08089] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Atherosclerosis and its clinical consequences are the leading cause of death in the western hemisphere. While many studies throughout the last decades have aimed at understanding the disease, the clinical markers in use today still fail to accurately predict the risks. The role of the current main clinical indicator, low density lipoprotein (LDL), in depositing fat to the vessel wall is believed to be the onset of the process. However, many subfractions of the LDL, which differ both in structure and composition, are present in the blood and among different individuals. Understanding the relationship between LDL structure and composition is key to unravel the specific role of various LDL components in the development and/or prevention of atherosclerosis. Here, we describe a model for analyzing small-angle X-ray scattering data for rapid and robust structure determination for the LDL. The model not only gives the overall structure but also the particular internal layering of the fats inside the LDL core. Thus, the melting of the LDL can be followed in situ as a function of temperature for samples extracted from healthy human patients and purified using a double protocol based on ultracentrifugation and size-exclusion chromatography. The model provides information on: (i) the particle-specific melting temperature of the core lipids, (ii) the structural organization of the core fats inside the LDL, (iii) the overall shape of the particle, and (iv) the flexibility and overall conformation of the outer protein/hydrophilic layer at a given temperature as governed by the organization of the core. The advantage of this method over other techniques such as cryo-TEM is the possibility of in situ experiments under near-physiological conditions which can be performed relatively fast (minutes at home source, seconds at synchrotron). This approach now allows the monitoring of structural changes in the LDL upon different stresses from the environment, such as changes in temperature, oxidation, or external agents used or currently in development against atherosclerotic plaque build-up and which are targeting the LDL.
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Affiliation(s)
- Selma Maric
- Biofilms- Research Center for Biointerfaces, Dept. of Biomedical Science, Faculty of Health and Society, Malmö University , Malmö 20506, Sweden
| | - Tania Kjellerup Lind
- Biofilms- Research Center for Biointerfaces, Dept. of Biomedical Science, Faculty of Health and Society, Malmö University , Malmö 20506, Sweden
| | - Jeppe Lyngsø
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , 8000 Aarhus, Denmark
| | - Marité Cárdenas
- Biofilms- Research Center for Biointerfaces, Dept. of Biomedical Science, Faculty of Health and Society, Malmö University , Malmö 20506, Sweden
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , 8000 Aarhus, Denmark
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Möller J, Léonardon J, Gorini J, Dattani R, Narayanan T. A sub-ms pressure jump setup for time-resolved X-ray scattering. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:125116. [PMID: 28040915 DOI: 10.1063/1.4972296] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a new experimental setup for time-resolved solution small-angle X-ray scattering (SAXS) studies of kinetic processes induced by sub-ms hydrostatic pressure jumps. It is based on a high-force piezo-stack actuator, with which the volume of the sample can be dynamically compressed. The presented setup has been designed and optimized for SAXS experiments with absolute pressures of up to 1000 bars, using transparent diamond windows and an easy-to-change sample capillary. The pressure in the cell can be changed in less than 1 ms, which is about an order of magnitude faster jump than previously obtained by dynamic pressure setups for SAXS. An additional temperature control offers the possibility for automated mapping of p-T phase diagrams. Here we present the technical specifications and first experimental data taken together with a preview of new research opportunities enabled by this setup.
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Di Cola E, Grillo I, Ristori S. Small Angle X-ray and Neutron Scattering: Powerful Tools for Studying the Structure of Drug-Loaded Liposomes. Pharmaceutics 2016; 8:pharmaceutics8020010. [PMID: 27043614 PMCID: PMC4932473 DOI: 10.3390/pharmaceutics8020010] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/09/2016] [Accepted: 03/14/2016] [Indexed: 12/12/2022] Open
Abstract
Nanovectors, such as liposomes, micelles and lipid nanoparticles, are recognized as efficient platforms for delivering therapeutic agents, especially those with low solubility in water. Besides being safe and non-toxic, drug carriers with improved performance should meet the requirements of (i) appropriate size and shape and (ii) cargo upload/release with unmodified properties. Structural issues are of primary importance to control the mechanism of action of loaded vectors. Overall properties, such as mean diameter and surface charge, can be obtained using bench instruments (Dynamic Light Scattering and Zeta potential). However, techniques with higher space and time resolution are needed for in-depth structural characterization. Small-angle X-ray (SAXS) and neutron (SANS) scattering techniques provide information at the nanoscale and have therefore been largely used to investigate nanovectors loaded with drugs or other biologically relevant molecules. Here we revise recent applications of these complementary scattering techniques in the field of drug delivery in pharmaceutics and medicine with a focus to liposomal carriers. In particular, we highlight those aspects that can be more commonly accessed by the interested users.
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Affiliation(s)
- Emanuela Di Cola
- Laboratoire Interdisciplinaire de Physique (LIPhy), Université Grenoble-Alpes, CNRS-UMR 5588, 140 rue de la Physique, 38402 Saint-Martin-d'Hères, France.
| | - Isabelle Grillo
- Institut Laue-Langevin (ILL) DS/LSS, CS 20156-38042 Grenoble Cedex 9, France.
| | - Sandra Ristori
- Dipartimento di Scienze della Terra, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
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10
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Kim JH, Kim Y, Bae KH, Park TG, Lee JH, Park K. Tumor-targeted delivery of paclitaxel using low density lipoprotein-mimetic solid lipid nanoparticles. Mol Pharm 2015; 12:1230-41. [PMID: 25686010 DOI: 10.1021/mp500737y] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Water-insoluble anticancer drugs, including paclitaxel, present severe clinical side effects when administered to patients, primarily associated with the toxicity of reagents used to solubilize the drugs. In efforts to develop alternative formulations of water-insoluble anticancer drugs suitable for intravenous administration, we developed biocompatible anticancer therapeutic solid lipid nanoparticles (SLNs), mimicking the structure and composition of natural particles, low-density lipoproteins (LDLs), for tumor-targeted delivery of paclitaxel. These therapeutic nanoparticles contained water-insoluble paclitaxel in the core with tumor-targeting ligand covalently conjugated on the polyethylene glycol (PEG)-modified surface (targeted PtSLNs). In preclinical human cancer xenograft mouse model studies, the paclitaxel-containing tumor-targeting SLNs exhibited pronounced in vivo stability and enhanced biocompatibility. Furthermore, these SLNs had superior antitumor activity to in-class nanoparticular therapeutics in clinical use (Taxol and Genexol-PM) and yielded long-term complete responses. The in vivo targeted antitumor activities of the SLN formulations in a mouse tumor model suggest that LDL-mimetic SLN formulations can be utilized as a biocompatible, tumor-targeting platform for the delivery of various anticancer therapeutics.
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Affiliation(s)
- Jin-Ho Kim
- †Medical Nanoelement Development Center, Samsung Biomedical Research Institute, Seoul 135-710, Republic of Korea.,‡Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Republic of Korea
| | - Youngwook Kim
- †Medical Nanoelement Development Center, Samsung Biomedical Research Institute, Seoul 135-710, Republic of Korea
| | - Ki Hyun Bae
- §Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Tae Gwan Park
- §Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Jung Hee Lee
- ‡Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Republic of Korea.,∥Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Republic of Korea
| | - Keunchil Park
- †Medical Nanoelement Development Center, Samsung Biomedical Research Institute, Seoul 135-710, Republic of Korea.,⊥Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Republic of Korea
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11
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Lee JY, Kim JH, Bae KH, Oh MH, Kim Y, Kim JS, Park TG, Park K, Lee JH, Nam YS. Low-density lipoprotein-mimicking nanoparticles for tumor-targeted theranostic applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:222-231. [PMID: 25137631 DOI: 10.1002/smll.201303277] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 07/06/2014] [Indexed: 06/03/2023]
Abstract
This study introduces multifunctional lipid nanoparticles (LNPs), mimicking the structure and compositions of low-density lipoproteins, for the tumor-targeted co-delivery of anti-cancer drugs and superparamagnetic nanocrystals. Paclitaxel (4.7 wt%) and iron oxide nanocrystals (6.8 wt%, 11 nm in diameter) are co-encapsulated within folate-functionalized LNPs, which contain a cluster of nanocrystals with an overall diameter of about 170 nm and a zeta potential of about -40 mV. The folate-functionalized LNPs enable the targeted detection of MCF-7, human breast adenocarcinoma expressing folate receptors, in T2 -weighted magnetic resonance images as well as the efficient intracellular delivery of paclitaxel. Paclitaxel-free LNPs show no significant cytotoxicity up to 0.2 mg mL(-1) , indicating the excellent biocompatibility of the LNPs for intracellular drug delivery applications. The targeted anti-tumor activities of the LNPs in a mouse tumor model suggest that the low-density lipoprotein-mimetic LNPs can be an effective theranostic platform with excellent biocompatibility for the tumor-targeted co-delivery of various anti-cancer agents.
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Affiliation(s)
- Jeong Yu Lee
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseung-gu, Daejeon, 305-701, Republic of Korea
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12
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Structural characterization of lipidic systems under nonequilibrium conditions. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2012; 41:831-40. [PMID: 22569535 DOI: 10.1007/s00249-012-0815-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 03/27/2012] [Accepted: 04/15/2012] [Indexed: 12/31/2022]
Abstract
This review covers recent studies on the characterization of the dynamics of lipidic nanostructures formed via self-assembly processes. The focus is placed on two main topics: First, an overview of advanced experimental small-angle X-ray scattering (SAXS) setups combined with various sample manipulation techniques including, for instance, stop-flow mixing or rapid temperature-jump perturbation is given. Second, our recent synchrotron SAXS findings on the dynamic structural response of gold nanoparticle-loaded vesicles upon exposure to an ultraviolet light source, the impact of rapidly mixing negatively charged vesicles with calcium ions, and in situ hydration-induced formation of inverted-type liquid-crystalline phases loaded with the local anesthetic bupivacaine are summarized. These in situ time-resolved experiments allow real-time monitoring of the dynamics of the structural changes and the possible formation of intermediate states in the millisecond to second range. The need for investigating self-assembled systems, mainly stimuli-responsive drug nanocarriers, under nonequilibrium conditions is discussed. For pharmaceutically relevant applications, it is essential to combine these investigations with appropriate in vitro and in vivo studies.
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Jayaraman S, Jasuja R, Zakharov MN, Gursky O. Pressure perturbation calorimetry of lipoproteins reveals an endothermic transition without detectable volume changes. Implications for adsorption of apolipoprotein to a phospholipid surface. Biochemistry 2011; 50:3919-27. [PMID: 21452855 DOI: 10.1021/bi200090y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Plasma lipoproteins are assemblies of lipids and apolipoproteins that mediate lipid transport and metabolism. High-density lipoproteins (HDL) remove excess cell cholesterol and provide protection against atherosclerosis. Important aspects of metabolic HDL remodeling, including apolipoprotein dissociation and lipoprotein fusion, are mimicked in thermal denaturation. We report the first study of the protein-lipid complexes by pressure perturbation calorimetry (PPC) beyond 100 °C. In PPC, volume expansion coefficient α(v)(T) is measured during heating; in proteins, α(v)(T) is dominated by hydration. Calorimetric studies of reconstituted HDL and of human high-density, low-density, and very low-density lipoproteins reveal that apolipoprotein unfolding, dissociation, and lipoprotein fusion are endothermic transitions without detectable volume changes. This may result from the limited applicability of PPC to slow kinetically controlled transitions such as thermal remodeling of lipoproteins and/or from the possibility that this remodeling causes no significant changes in the solvent structure and, hence, may not involve large transient solvent exposure of apolar moieties. Another conclusion is that apolipoprotein A-I in solution adsorbs to the phospholipid surface; protein hydration is preserved upon such adsorption. We posit that adsorption to a phospholipid surface helps recruit free apolipoprotein to the plasma membrane and facilitate HDL biogenesis.
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Affiliation(s)
- Shobini Jayaraman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, United States.
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Jayaraman S, Gantz DL, Gursky O. Effects of phospholipase A(2) and its products on structural stability of human LDL: relevance to formation of LDL-derived lipid droplets. J Lipid Res 2011; 52:549-57. [PMID: 21220788 DOI: 10.1194/jlr.m012567] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hydrolysis and oxidation of LDL stimulate LDL entrapment in the arterial wall and promote inflammation and atherosclerosis via various mechanisms including lipoprotein fusion and lipid droplet formation. To determine the effects of FFA on these transitions, we hydrolyzed LDL by phospholipase A(2) (PLA(2)), removed FFA by albumin, and analyzed structural stability of the modified lipoproteins. Earlier, we showed that heating induces LDL remodeling, rupture, and coalescence into lipid droplets resembling those found in atherosclerotic lesions. Here, we report how FFA affect these transitions. Circular dichroism showed that mild LDL lipolysis induces partial β-sheet unfolding in apolipoprotein B. Electron microscopy, turbidity, and differential scanning calorimetry showed that mild lipolysis promotes LDL coalescence into lipid droplets. FFA removal by albumin restores LDL stability but not the protein conformation. Consequently, FFA enhance LDL coalescence into lipid droplets. Similar effects of FFA were observed in minimally oxidized LDL, in LDL enriched with exogenous FFA, and in HDL and VLDL. Our results imply that FFA promote lipoprotein coalescence into lipid droplets and explain why LDL oxidation enhances such coalescence in vivo but hampers it in vitro. Such lipid droplet formation potentially contributes to the pro-atherogenic effects of FFA.
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Affiliation(s)
- Shobini Jayaraman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA.
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Prassl R. Human low density lipoprotein: the mystery of core lipid packing. J Lipid Res 2010; 52:187-8. [PMID: 21131533 DOI: 10.1194/jlr.e013417] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Ruth Prassl
- Institute of Biophysics and Nanosystems Research, Austrian Academy of Sciences, Graz, Austria.
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Liu Y, Luo D, Atkinson D. Human LDL core cholesterol ester packing: three-dimensional image reconstruction and SAXS simulation studies. J Lipid Res 2010; 52:256-62. [PMID: 21047995 DOI: 10.1194/jlr.m011569] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human LDL undergoes a reversible thermal order-disorder phase transition associated with the cholesterol ester packing in the lipid core. Structural changes associated with this phase transition have been shown to affect the resistance of LDL to oxidation in vitro studies. Previous electron cryo-microscopy studies have provided image evidence that the cholesterol ester is packed in three flat layers in the core at temperatures below the phase transition. To study changes in lipid packing, overall structure and particle morphology in three dimensions (3D) subsequent to the phase transition, we cryo-preserved human LDL at a temperature above phase transition (53°C) and examined the sample by electron microscopy and image reconstruction. The LDL frozen from 53°C adopted a different morphology. The central density layer was disrupted and the outer two layers formed a "disrupted shell"-shaped density, located concentrically underneath the surface density of the LDL particle. Simulation of the small angle X-ray scattering curves and comparison with published data suggested that this disrupted shell organization represents an intermediate state in the transition from isotropic to layered packing of the lipid. Thus, the results revealed, with 3D images, the lipid packing in the dynamic process of the LDL lipid-core phase transition.
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Affiliation(s)
- Yuhang Liu
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA
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17
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Benjwal S, Gursky O. Pressure perturbation calorimetry of apolipoproteins in solution and in model lipoproteins. Proteins 2010; 78:1175-85. [PMID: 19927327 DOI: 10.1002/prot.22637] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
High-density lipoproteins (HDLs) are complexes of lipids and proteins (termed apolipoproteins) that remove cell cholesterol and protect from atherosclerosis. Apolipoproteins contain amphipathic alpha-helices that have high content (> or = 1/3) and distinct distribution of charged and apolar residues, adopt molten globule-like conformations in solution, and bind to lipid surfaces. We report the first pressure perturbation calorimetry (PPC) study of apolipoproteins. In solution, the main HDL protein, apoA-I, shows relatively large volume contraction, DeltaV(unf) = -0.33%, and an apparent reduction in thermal expansivity upon unfolding, Deltaalpha(unf) < or = 0, which has not been observed in other proteins. We propose that these values are dominated by increased charged residue hydration upon alpha-helical unfolding, which may result from disruption of multiple salt bridges. At 5 degrees C, apoA-I shows large thermal expansion coefficient, alpha(5 degrees) = 15.10(-4) K(-1), that rapidly declines upon heating from 5 to 40 degrees C, alpha(40 degrees) - alpha(5 degrees) = -4.10(-4) K(-1); apolipoprotein C-I shows similar values of alpha(5 degrees) and alpha(40 degrees). These values are larger than in globular proteins. They indicate dominant effect of charged residue hydration, which may modulate functional apolipoprotein interactions with a broad range of their protein and lipid ligands. The first PPC analysis of a protein-lipid complex is reported, which focuses on the chain melting transition in model HDL containing apoA-I or apoC-I, dimyristoyl phosphatidylcholine, and 0-20% cholesterol. The results may provide new insights into volumetric properties of HDL that modulate metabolic lipoprotein remodeling during cholesterol transport.
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Affiliation(s)
- Sangeeta Benjwal
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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