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Xue H, Zhang M, Liu J, Wang J, Ren G. Structure-based mechanism and inhibition of cholesteryl ester transfer protein. Curr Atheroscler Rep 2023; 25:155-166. [PMID: 36881278 PMCID: PMC10027838 DOI: 10.1007/s11883-023-01087-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2023] [Indexed: 03/08/2023]
Abstract
PURPOSE OF REVIEW Cholesteryl ester transfer proteins (CETP) regulate plasma cholesterol levels by transferring cholesteryl esters (CEs) among lipoproteins. Lipoprotein cholesterol levels correlate with the risk factors for atherosclerotic cardiovascular disease (ASCVD). This article reviews recent research on CETP structure, lipid transfer mechanism, and its inhibition. RECENT FINDINGS Genetic deficiency in CETP is associated with a low plasma level of low-density lipoprotein cholesterol (LDL-C) and a profoundly elevated plasma level of high-density lipoprotein cholesterol (HDL-C), which correlates with a lower risk of atherosclerotic cardiovascular disease (ASCVD). However, a very high concentration of HDL-C also correlates with increased ASCVD mortality. Considering that the elevated CETP activity is a major determinant of the atherogenic dyslipidemia, i.e., pro-atherogenic reductions in HDL and LDL particle size, inhibition of CETP emerged as a promising pharmacological target during the past two decades. CETP inhibitors, including torcetrapib, dalcetrapib, evacetrapib, anacetrapib and obicetrapib, were designed and evaluated in phase III clinical trials for the treatment of ASCVD or dyslipidemia. Although these inhibitors increase in plasma HDL-C levels and/or reduce LDL-C levels, the poor efficacy against ASCVD ended interest in CETP as an anti-ASCVD target. Nevertheless, interest in CETP and the molecular mechanism by which it inhibits CE transfer among lipoproteins persisted. Insights into the structural-based CETP-lipoprotein interactions can unravel CETP inhibition machinery, which can hopefully guide the design of more effective CETP inhibitors that combat ASCVD. Individual-molecule 3D structures of CETP bound to lipoproteins provide a model for understanding the mechanism by which CETP mediates lipid transfer and which in turn, guide the rational design of new anti-ASCVD therapeutics.
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Affiliation(s)
- Han Xue
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | - Meng Zhang
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jianfang Liu
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jianjun Wang
- Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | - Gang Ren
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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2
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Aluganti Narasimhulu C, Parthasarathy S. Preparation of LDL , Oxidation , Methods of Detection, and Applications in Atherosclerosis Research. Methods Mol Biol 2022; 2419:213-246. [PMID: 35237967 DOI: 10.1007/978-1-0716-1924-7_13] [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] [Indexed: 06/14/2023]
Abstract
The concept of lipid peroxidation has been known for a long time. It is now well established that LDL plays a major role in atherosclerosis. Oxidized low-density lipoprotein (Ox-LDL) has been studied for over 35 years. Numerous pro- and anti-atherogenic properties have been attributed to Ox-LDL. Component composition of Ox-LDL is complex due to the influence of various factors, including the source, method of preparation, storage and use. Hence, it is very difficult to clearly define and characterize Ox-LDL. It contains unoxidized and oxidized fatty acid derivatives both in the ester and free forms, their decomposition products, cholesterol and its oxidized products, proteins with oxidized amino acids and cross-links, polypeptides with varying extents of covalent modification with lipid oxidation products and many others. The measurement of lipid oxidation has been a great boon, not only to the understanding of the process but also in providing numerous serendipitous discoveries and methodologies. In this chapter, we outline the methodologies for the preparation and testing of various lipoproteins for oxidation studies.
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Affiliation(s)
| | - Sampath Parthasarathy
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
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3
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Orozco Morales JA, Medina Urrutia AX, Torres Tamayo M, Jorge Galarza E, Reyes Barrera J, Díes Suarez P, Juárez Rojas JG, Medina-Bravo P. Effects of fatty liver on the size and composition of high-density lipoprotein cholesterol subpopulations in adolescents with type 2 diabetes mellitus. Pediatr Diabetes 2020; 21:1140-1149. [PMID: 32812688 DOI: 10.1111/pedi.13103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/05/2020] [Accepted: 08/12/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Type 2 diabetes mellitus (T2DM) is an emerging disease in the pediatric population. The association between T2DM and non-alcoholic fatty liver disease (NAFLD) has been described. Recent evidence suggests that sizes and composition of high-density lipoprotein (HDL) may be more important that HDL-C levels in predicting coronary heart disease. There is not data regarding the HDL subclasses distribution and composition in T2DM youths with NAFLD. METHODS This cross-sectional study included 47 adolescents with T2DM and 23 non-diabetic controls of both sexes aged 10 to 18 years. The presence of NAFLD was determined estimated proton density fat fraction (PDFF) by magnetic resonance by spectroscopy. We compared the HDL subclasses distribution (HDL2b, HDL2a, HDL3a HDL3b and HDL3c) and the HDL chemical composition (total protein, triglyceride, phospholipid, cholesteryl esters, and free cholesterol) between the groups of adolescents with T2DM and the control group. RESULTS Patients with T2DM and NAFLD had a significantly lower proportion HDL2b (P = .040) and a higher proportion of HDL3c (P = .035); higher proportion of TG (P = .032) and a lower CE (P = .002) and FC (P < .001). A negative association was observed between PDFF and the percentages of HDL2b (r2 = -0.341, P = .004) and the average particle size (r2 = -0.327, P = .05), and a positive association with HDL3c subpopulations (r2 = 0.327, P = .015); about composition inside HDL particle, a positive association with PDFF and the TG (r2 = 0.299, P = .013) and negative with CE (r2 = -0.265, P = .030). CONCLUSIONS In adolescents diagnosed with T2DM, the presence of NAFLD is associated with abnormalities in the distribution of HDL subpopulations and the lipid composition of HDL particles.
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Affiliation(s)
| | | | - Margarita Torres Tamayo
- Endocrinology Department, Instituto Nacional de Cardiologia Ignacio Chávez, Mexico City, Mexico
| | - Esteban Jorge Galarza
- Endocrinology Department, Instituto Nacional de Cardiologia Ignacio Chávez, Mexico City, Mexico
| | - Juan Reyes Barrera
- Endocrinology Department, Instituto Nacional de Cardiologia Ignacio Chávez, Mexico City, Mexico
| | - Pilar Díes Suarez
- Imagenology Department, Hospital Infantil de Mexico Federico Gomez, Mexico City, Mexico
| | | | - Patricia Medina-Bravo
- Endocrinology Department, Hospital Infantil de Mexico Federico Gomez, Mexico City, Mexico
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4
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Zhang M, Zhai X, Li J, Albers JJ, Vuletic S, Ren G. Structural basis of the lipid transfer mechanism of phospholipid transfer protein (PLTP). Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1082-1094. [PMID: 29883800 PMCID: PMC6114099 DOI: 10.1016/j.bbalip.2018.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 05/10/2018] [Accepted: 06/01/2018] [Indexed: 12/14/2022]
Abstract
Human phospholipid transfer protein (PLTP) mediates the transfer of phospholipids among atheroprotective high-density lipoproteins (HDL) and atherogenic low-density lipoproteins (LDL) by an unknown mechanism. Delineating this mechanism would represent the first step towards understanding PLTP-mediated lipid transfers, which may be important for treating lipoprotein abnormalities and cardiovascular disease. Here, using various electron microscopy techniques, PLTP is revealed to have a banana-shaped structure similar to cholesteryl ester transfer protein (CETP). We provide evidence that PLTP penetrates into the HDL and LDL surfaces, respectively, and then forms a ternary complex with HDL and LDL. Insights into the interaction of PLTP with lipoproteins at the molecular level provide a basis to understand the PLTP-dependent lipid transfer mechanisms for dyslipidemia treatment.
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Affiliation(s)
- Meng Zhang
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Xiaobo Zhai
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Jinping Li
- Department of Biomedical Science, Mercer University School of Medicine, Savannah, GA 31404, United States
| | - John J Albers
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Seattle, WA 98109, United States
| | - Simona Vuletic
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Seattle, WA 98109, United States.
| | - Gang Ren
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States.
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5
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Latour A, Salameh S, Carbonne C, Daubigney F, Paul JL, Kergoat M, Autier V, Delabar JM, De Geest B, Janel N. Corrective effects of hepatotoxicity by hepatic Dyrk1a gene delivery in mice with intermediate hyperhomocysteinemia. Mol Genet Metab Rep 2015. [PMID: 28649528 PMCID: PMC5471159 DOI: 10.1016/j.ymgmr.2014.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Hyperhomocysteinemia results from hepatic metabolism dysfunction and is characterized by a high plasma homocysteine level, which is also an independent risk factor for cardiovascular disease. Elevated levels of homocysteine in plasma lead to hepatic lesions and abnormal lipid metabolism. Therefore, lowering homocysteine levels might offer therapeutic benefits. Recently, we were able to lower plasma homocysteine levels in mice with moderate hyperhomocysteinemia using an adenoviral construct designed to restrict the expression of DYRK1A, a serine/threonine kinase involved in methionine metabolism (and therefore homocysteine production), to hepatocytes. Here, we aimed to extend our previous findings by analyzing the effect of hepatocyte-specific Dyrk1a gene transfer on intermediate hyperhomocysteinemia and its associated hepatic toxicity and liver dysfunction. Commensurate with decreased plasma homocysteine and alanine aminotransferase levels, targeted hepatic expression of DYRK1A in mice with intermediate hyperhomocysteinemia resulted in elevated plasma paraoxonase-1 and lecithin:cholesterol acyltransferase activities and apolipoprotein A-I levels. It also rescued hepatic apolipoprotein E, J, and D levels. Further, Akt/GSK3/cyclin D1 signaling pathways in the liver of treated mice were altered, which may help prevent homocysteine-induced cell cycle dysfunction. DYRK1A gene therapy could be useful in the treatment of hyperhomocysteinemia in populations, such as end-stage renal disease patients, who are unresponsive to B-complex vitamin therapy.
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Key Words
- ALT, alanine aminotransferase
- APO, apolipoprotein
- Alanine aminotransferase
- Apolipoproteins
- CBS, cystathionine beta synthase
- DCPIP, 2,6-dichlorophenolindophenol
- Dyrk1a gene transfer
- HDLs, high-density lipoproteins
- HPLC, high-performance liquid chromatography
- Intermediate hyperhomocysteinemia
- KYNA, kynurenic acid
- LCAT, lecithin:cholesterol acyltransferase
- Lecithin:cholesterol acyltransferase
- Mice
- NQO1, NAD(P)H:quinone oxidoreductase
- PBS, phosphate-buffered saline
- PCR, polymerase chain reaction
- PON-1, paraoxonase-1
- SAH, S-adenosylhomocysteine
- SAHH, S-adenosylhomocysteine hydrolase
- SAM, S-adenosylmethionine
- VLDL, very low-density lipoprotein.
- hcy, homocysteine
- hhcy, hyperhomocysteinemia
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Affiliation(s)
- Alizée Latour
- Univ Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251 CNRS, F-75205 Paris, France
| | - Sacha Salameh
- Univ Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251 CNRS, F-75205 Paris, France
| | - Christel Carbonne
- Metabrain Research, Chilly Mazarin, France.,Brain & Spine Institute (ICM) CNRS UMR7225, INSERM UMRS 975, Paris, France
| | - Fabrice Daubigney
- Univ Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251 CNRS, F-75205 Paris, France
| | - Jean-Louis Paul
- AP-HP, Hôpital Européen Georges Pompidou, Service de Biochimie, 75015 Paris, France.,Univ Paris-Sud, EA 4529, UFR de Pharmacie, 92296 Châtenay-Malabry, France
| | - Micheline Kergoat
- Metabrain Research, Chilly Mazarin, France.,Brain & Spine Institute (ICM) CNRS UMR7225, INSERM UMRS 975, Paris, France
| | - Valérie Autier
- Metabrain Research, Chilly Mazarin, France.,Brain & Spine Institute (ICM) CNRS UMR7225, INSERM UMRS 975, Paris, France
| | - Jean-Maurice Delabar
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France
| | - Bart De Geest
- Center for Molecular and Vascular Biology, University of Leuven, Campus Gasthuisberg, 3000 Leuven, Belgium
| | - Nathalie Janel
- Univ Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251 CNRS, F-75205 Paris, France
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6
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Zannis VI, Fotakis P, Koukos G, Kardassis D, Ehnholm C, Jauhiainen M, Chroni A. HDL biogenesis, remodeling, and catabolism. Handb Exp Pharmacol 2015; 224:53-111. [PMID: 25522986 DOI: 10.1007/978-3-319-09665-0_2] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In this chapter, we review how HDL is generated, remodeled, and catabolized in plasma. We describe key features of the proteins that participate in these processes, emphasizing how mutations in apolipoprotein A-I (apoA-I) and the other proteins affect HDL metabolism. The biogenesis of HDL initially requires functional interaction of apoA-I with the ATP-binding cassette transporter A1 (ABCA1) and subsequently interactions of the lipidated apoA-I forms with lecithin/cholesterol acyltransferase (LCAT). Mutations in these proteins either prevent or impair the formation and possibly the functionality of HDL. Remodeling and catabolism of HDL is the result of interactions of HDL with cell receptors and other membrane and plasma proteins including hepatic lipase (HL), endothelial lipase (EL), phospholipid transfer protein (PLTP), cholesteryl ester transfer protein (CETP), apolipoprotein M (apoM), scavenger receptor class B type I (SR-BI), ATP-binding cassette transporter G1 (ABCG1), the F1 subunit of ATPase (Ecto F1-ATPase), and the cubulin/megalin receptor. Similarly to apoA-I, apolipoprotein E and apolipoprotein A-IV were shown to form discrete HDL particles containing these apolipoproteins which may have important but still unexplored functions. Furthermore, several plasma proteins were found associated with HDL and may modulate its biological functions. The effect of these proteins on the functionality of HDL is the topic of ongoing research.
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Affiliation(s)
- Vassilis I Zannis
- Molecular Genetics, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, 02118, USA,
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7
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Gauthamadasa K, Vaitinadin NS, Dressman JL, Macha S, Homan R, Greis KD, Silva RAGD. Apolipoprotein A-II-mediated conformational changes of apolipoprotein A-I in discoidal high density lipoproteins. J Biol Chem 2012; 287:7615-25. [PMID: 22235130 DOI: 10.1074/jbc.m111.291070] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
It is well accepted that HDL has the ability to reduce risks for several chronic diseases. To gain insights into the functional properties of HDL, it is critical to understand the HDL structure in detail. To understand interactions between the two major apolipoproteins (apos), apoA-I and apoA-II in HDL, we generated highly defined benchmark discoidal HDL particles. These particles were reconstituted using a physiologically relevant phospholipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) incorporating two molecules of apoA-I and one homodimer of apoA-II per particle. We utilized two independent mass spectrometry techniques to study these particles. The techniques are both sensitive to protein conformation and interactions and are namely: 1) hydrogen deuterium exchange combined with mass spectrometry and 2) partial acetylation of lysine residues combined with MS. Comparison of mixed particles with apoA-I only particles of similar diameter revealed that the changes in apoA-I conformation in the presence of apoA-II are confined to apoA-I helices 3-4 and 7-9. We discuss these findings with respect to the relative reactivity of these two particle types toward a major plasma enzyme, lecithin:cholesterol acyltransferase responsible for the HDL maturation process.
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Affiliation(s)
- Kekulawalage Gauthamadasa
- Department of Pathology and Laboratory Medicine, Center for Lipids and Atherosclerosis Sciences, University of Cincinnati, Cincinnati, Ohio 45267, USA
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8
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Manufacturing and shelf stability of reconstituted high-density lipoprotein for infusion therapy. BIOTECHNOL BIOPROC E 2011. [DOI: 10.1007/s12257-010-0421-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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9
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Guo X, Yu M, Kang X, Yin H. mTOR Complex 2 Activation by Reconstituted High-Density Lipoprotein Prevents Senescence in Circulating Angiogenic Cells. Arterioscler Thromb Vasc Biol 2011; 31:1421-9. [PMID: 21415389 DOI: 10.1161/atvbaha.111.224089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Circulating angiogenic cells (CACs) participate in neovascularization and arterial repair. Although high-density lipoprotein (HDL) is known to enhance the functional activity of CACs, the mechanisms underlying this regulation are poorly understood. Here, we examined the mechanism(s) by which reconstituted HDL (rHDL) affects CAC senescence.
Methods and Results—
CACs isolated from human peripheral blood and treated with rHDL displayed reduced senescence, as measured by acidic β-galactosidase staining. This protective effect was blocked by the mammalian target of rapamycin (mTOR) inhibitor (rapamycin). According to Western blot analysis and immunoprecipitation results, rHDL promoted mTOR phosphorylation, mTOR-rictor complex formation, and mTOR-rictor–dependent Akt activation, which were accompanied by increased nuclear translocation of human telomerase reverse transcriptase and enhanced nuclear telomerase activity. Suppression of rictor gene expression with a small interfering RNA blocked mTOR-rictor complex formation and Akt activation. The suppression also abolished the rHDL-induced inhibition of CAC senescence and promotion of nuclear telomerase activity. Treatment of aged mice with rHDL attenuated spleen-derived CAC senescence. In CACs isolated from rHDL-treated aged mice, the phosphorylated mTOR and Akt levels were significantly enhanced.
Conclusion—
rHDL stimulates sustained mTOR phosphorylation and mTOR-rictor complex formation and inhibits senescence onset in CACs through mTOR complex 2 pathway activation.
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Affiliation(s)
- Xianrong Guo
- From the Department of Pathology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China (X.G., X.K., H.Y.); Key Laboratory of Endocrinology, Ministry of Health, Department of Endocrinology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (M.Y.)
| | - Miao Yu
- From the Department of Pathology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China (X.G., X.K., H.Y.); Key Laboratory of Endocrinology, Ministry of Health, Department of Endocrinology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (M.Y.)
| | - Xiaomin Kang
- From the Department of Pathology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China (X.G., X.K., H.Y.); Key Laboratory of Endocrinology, Ministry of Health, Department of Endocrinology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (M.Y.)
| | - Hongchao Yin
- From the Department of Pathology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China (X.G., X.K., H.Y.); Key Laboratory of Endocrinology, Ministry of Health, Department of Endocrinology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People's Republic of China (M.Y.)
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10
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Nicholls SJ, Gordon A, Johansson J, Wolski K, Ballantyne CM, Kastelein JJP, Taylor A, Borgman M, Nissen SE. Efficacy and safety of a novel oral inducer of apolipoprotein a-I synthesis in statin-treated patients with stable coronary artery disease a randomized controlled trial. J Am Coll Cardiol 2011; 57:1111-9. [PMID: 21255957 DOI: 10.1016/j.jacc.2010.11.015] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 11/03/2010] [Accepted: 11/10/2010] [Indexed: 01/28/2023]
Abstract
OBJECTIVES The purpose of this study was to investigate the safety, tolerability, and efficacy of RVX-208, the first oral agent designed to enhance apolipoprotein (apo) A-I synthesis. BACKGROUND No agent that selectively induces synthesis of apoA-I has reached an advanced stage of clinical development. METHODS A total of 299 statin-treated patients with coronary artery disease were treated with placebo or with RVX-208 at a dose of 50, 100, or 150 mg twice daily for 12 weeks. Changes in lipid-related biomarkers, in addition to safety and tolerability, of RVX-208 were investigated. RESULTS For each dose of RVX-208, individual pairwise comparisons of apoA-I changes with placebo, the primary end point, did not achieve statistical significance. However, treatment with RVX-208 was associated with a dose-dependent increase in apoA-I levels by up to 5.6% (p = 0.035 for trend). Administration of RVX-208 resulted in significant increases in levels of high-density lipoprotein cholesterol (HDL-C) ranging from 3.2% to 8.3% (p = 0.02), and large HDL particles increased by 11.1% to 21.1% (p = 0.003). ApoA-I levels increased rapidly from 8 to 12 weeks, suggesting that peak pharmacological effect has not been achieved by the end of the 12-week study. Transient and reversible elevations in liver transaminases >3 times the upper limit of normal were observed in 18 patients treated with RVX-208, with no associated increase in bilirubin levels. CONCLUSIONS Administration of RVX-208 for 12 weeks was associated with increases in apoA-I, HDL-C, and concentration of large HDL particles, consistent with facilitation of cholesterol mobilization. Maximal increases in apoA-I may require longer exposure. An increase in liver enzymes was observed with active treatment. (Clinical Trial for Dose Finding and Safety of RVX000222 in Subjects With Stable Coronary Artery Disease; NCT01058018).
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Affiliation(s)
- Stephen J Nicholls
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio 44195, USA.
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11
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Griffiths R, Barbour S. Lipoproteins and lipoprotein metabolism in periodontal disease. CLINICAL LIPIDOLOGY 2010; 5:397-411. [PMID: 20835400 PMCID: PMC2933935 DOI: 10.2217/clp.10.27] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A growing body of evidence indicates that the incidence of atherosclerosis is increased in subjects with periodontitis - a chronic infection of the oral cavity. This article summarizes the evidence that suggests periodontitis shifts the lipoprotein profile to be more proatherogenic. LDL-C is elevated in periodontitis and most studies indicate that triglyceride levels are also increased. By contrast, antiatherogenic HDL tends to be low in periodontitis. Periodontal therapy tends to shift lipoprotein levels to a healthier profile and also reduces subclinical indices of atherosclerosis. In summary, periodontal disease alters lipoprotein metabolism in ways that could promote atherosclerosis and cardiovascular disease.
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Affiliation(s)
- Rachel Griffiths
- Department of Biochemistry & Molecular Biology, Virginia Commonwealth University School of Medicine, Box 980614, Richmond, VA 23298-0614, USA
| | - Suzanne Barbour
- Department of Biochemistry & Molecular Biology, Virginia Commonwealth University School of Medicine, Box 980614, Richmond, VA 23298-0614, USA
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12
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Zheng H, Cong H, Wang H, Jin Q, Zhao J. A Microchip-Based Method for Rapid Separation of Subclasses of High-Density Lipoprotein. Chromatographia 2010. [DOI: 10.1365/s10337-010-1602-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Natarajan P, Ray KK, Cannon CP. High-Density Lipoprotein and Coronary Heart Disease. J Am Coll Cardiol 2010; 55:1283-99. [PMID: 20338488 DOI: 10.1016/j.jacc.2010.01.008] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 01/04/2010] [Accepted: 01/04/2010] [Indexed: 12/29/2022]
Affiliation(s)
- Pradeep Natarajan
- Department of Medicine, Cardiovascular Division, Brigham & Women's Hospital/Harvard Medical School, Boston, Massachusetts 02115, USA
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14
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Field FJ, Watt K, Mathur SN. TNF-alpha decreases ABCA1 expression and attenuates HDL cholesterol efflux in the human intestinal cell line Caco-2. J Lipid Res 2010; 51:1407-15. [PMID: 20103810 DOI: 10.1194/jlr.m002410] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HDL cholesterol levels are decreased in Crohn's disease, a tumor necrosis factor-alpha (TNF-alpha)-driven chronic inflammatory condition involving the gastrointestinal tract. ATP-binding cassette transporter A1 (ABCA1), one of several liver X receptor (LXR) target genes, is a cell surface transporter that mediates the rate-controlling step in HDL synthesis. The regulation of ABCA1 and HDL cholesterol efflux by TNF-alpha was investigated in the human intestinal cell line Caco-2. In response to cholesterol micelles or T0901317, an LXR nonsterol agonist, TNF-alpha decreased the basolateral efflux of cholesterol to apolipoprotein A1 (apoA1). TNF-alpha, by attenuating ABCA1 promoter activity, markedly decreased ABCA1 gene expression without attenuating the expression of LXR-alpha, LXR-beta, and most other LXR target genes, such as ABCG1, FAS, ABCG8, scavenger receptor-B1 (SR-B1), and apoC1. TNF-alpha also decreased ABCA1 mass by markedly enhancing the rate of ABCA1 degradation and modestly inhibiting its rate of synthesis. Inhibitors of the nuclear factor-kappaB (NF-kappaB) pathway, which is activated by TNF-alpha, partially reverse the effect of TNF-alpha on ABCA1 protein expression. The results suggest that TNF-alpha, the major cytokine implicated in the inflammation of Crohn's disease, decreases HDL cholesterol levels by attenuating the expression of intestinal ABCA1 and cholesterol efflux to apoA1.
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Affiliation(s)
- F Jeffrey Field
- Department of Internal, Medicine University of Iowa, Iowa City, IA 52242, USA. f-jeffrey-fi
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Abstract
Oxidized low-density lipoprotein (Ox-LDL) has been studied for over 25 years. Numerous pro- and anti-atherogenic properties have been attributed to Ox-LDL. Yet, Ox-LDL has neither been defined nor characterized, as its components and composition change depending on its source, method of preparation, storage, and use. It contains unoxidized and oxidized fatty acid derivatives both in the ester and free forms, their decomposition products, cholesterol and its oxidized products, proteins with oxidized amino acids and cross-links, and polypeptides with varying extents of covalent modification with lipid oxidation products, and many others. It seems to exist in vivo in some form not yet fully characterized. Until its pathophysiological significance, and how it is generated in vivo are determined, the nature of its true identity will be only of classical interest. In this review, its components, their biological actions and methods of preparation will be discussed.
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Affiliation(s)
- Sampath Parthasarathy
- Division of Cardiothoracic Surgery, The Ohio State University Medical Center, Columbus, OH, USA
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16
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Chen B, Ren X, Neville T, Jerome WG, Hoyt DW, Sparks D, Ren G, Wang J. Apolipoprotein AI tertiary structures determine stability and phospholipid-binding activity of discoidal high-density lipoprotein particles of different sizes. Protein Sci 2009; 18:921-35. [PMID: 19384992 DOI: 10.1002/pro.101] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human high-density lipoprotein (HDL) plays a key role in the reverse cholesterol transport pathway that delivers excess cholesterol back to the liver for clearance. In vivo, HDL particles vary in size, shape and biological function. The discoidal HDL is a 140-240 kDa, disk-shaped intermediate of mature HDL. During mature spherical HDL formation, discoidal HDLs play a key role in loading cholesterol ester onto the HDL particles by activating the enzyme, lecithin:cholesterol acyltransferase (LCAT). One of the major problems for high-resolution structural studies of discoidal HDL is the difficulty in obtaining pure and, foremost, homogenous sample. We demonstrate here that the commonly used cholate dialysis method for discoidal HDL preparation usually contains 5-10% lipid-poor apoAI that significantly interferes with the high-resolution structural analysis of discoidal HDL using biophysical methods. Using an ultracentrifugation method, we quickly removed lipid-poor apoAI. We also purified discoidal reconstituted HDL (rHDL) into two pure discoidal HDL species of different sizes that are amendable for high-resolution structural studies. A small rHDL has a diameter of 7.6 nm, and a large rHDL has a diameter of 9.8 nm. We show that these two different sizes of discoidal HDL particles display different stability and phospholipid-binding activity. Interestingly, these property/functional differences are independent from the apoAI alpha-helical secondary structure, but are determined by the tertiary structural difference of apoAI on different discoidal rHDL particles, as evidenced by two-dimensional NMR and negative stain electron microscopy data. Our result further provides the first high-resolution NMR data, demonstrating a promise of structural determination of discoidal HDL at atomic resolution using a combination of NMR and other biophysical techniques.
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Affiliation(s)
- Bin Chen
- Department of Biochemistry and Molecular Biology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA
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17
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Abstract
The origins of cholesterol utilized by intestinal ABCA1 were investigated in the human intestinal cell line Caco-2. Influx of apical membrane cholesterol increases ABCA1 mRNA and mass, resulting in enhanced efflux of HDL-cholesterol. Luminal (micellar) cholesterol and newly synthesized cholesterol are not transported directly to ABCA1 but reach the ABCA1 pool after incorporation into the apical membrane. Depleting the apical or the basolateral membrane of cholesterol by cyclodextrin attenuates the amount of cholesterol transported by ABCA1 without altering ABCA1 expression. Filipin added to the apical side but not the basal side attenuates ABCA1-mediated cholesterol efflux, suggesting that apical membrane "microdomains," or rafts, supply cholesterol for HDL. Preventing cholesterol esterification increases the amount of cholesterol available for HDL. Ezetimibe, a Niemann-Pick C1-like 1 protein inhibitor, does not alter ABCA1-mediated cholesterol efflux. U18666A and imipramine, agents that mimic cholesterol trafficking defects of Neimann-Pick type C disease, attenuate cholesterol efflux without altering ABCA1 expression; thus, intestinal NPC1 may facilitate cholesterol movement to ABCA1. ABCA1-mediated cholesterol efflux is independent of cholesterol synthesis. The results suggest that following incorporation into plasma membrane and rafts of the apical membrane, dietary/biliary and newly synthesized cholesterol contribute to the ABCA1 pool and HDL-cholesterol. NPC1 may have a role in this process.
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Affiliation(s)
- F Jeffrey Field
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA.
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18
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CYP3A53A allele is associated with reduced lowering-lipid response to atorvastatin in individuals with hypercholesterolemia. Clin Chim Acta 2008; 398:15-20. [PMID: 18727922 DOI: 10.1016/j.cca.2008.07.032] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 07/29/2008] [Accepted: 07/31/2008] [Indexed: 11/23/2022]
Abstract
BACKGROUND The cytochrome P450 isoenzyme 3A5 (CYP3A5) has an important role on biotransformation of xenobiotics. CYP3A5 SNPs have been associated with variations on enzyme activity that can modify the metabolism of several drugs. METHODS In order to evaluate the influence of CYP3A5 variants on response to lowering-cholesterol drugs, 139 individuals with hypercholesterolemia were selected. After a wash-out period of 4 weeks, individuals were treated with atorvastatin (10 mg/day/4 weeks). Genomic DNA was extracted by a salting-out procedure. CYP3A5*3C, CYP3A5*6 and CYP3A5*1D were analyzed by PCR-RFLP and DNA sequencing. RESULTS >Frequencies of the CYP3A5*3C and CYP3A5*1D alleles were lower in individuals of African descent (*3C: 47.8% and *1D: 55.2%) than in non-Africans (*3C: 84.9% and *1D 84.8%, p<0.01). Non-Africans carrying *3A allele (*3C and *1D combined alleles) had lower total and LDL-cholesterol response to atorvastatin than non-*3A allele carriers (p<0.05). CONCLUSION CYP3A5*3A allele is associated with reduced cholesterol-lowering response to atorvastatin in non-African individuals.
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McTaggart F, Jones P. Effects of statins on high-density lipoproteins: a potential contribution to cardiovascular benefit. Cardiovasc Drugs Ther 2008; 22:321-38. [PMID: 18553127 PMCID: PMC2493531 DOI: 10.1007/s10557-008-6113-z] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 04/04/2008] [Indexed: 12/12/2022]
Abstract
PURPOSE The objective was to systematically review clinical trial data on the effects of statins on high-density lipoproteins (HDL) and to examine the possibility that this provides cardiovascular benefits in addition to those derived from reductions in low-density lipoproteins (LDL). METHODS The PubMed database was searched for publications describing clinical trials of atorvastatin, pravastatin, rosuvastatin, and simvastatin. On the basis of predefined criteria, 103 were selected for review. RESULTS Compared with placebo, statins raise HDL, measured as HDL-cholesterol (HDL-C) and apolipoprotein A-I (apo A-I); these elevations are maintained in the long-term. In hypercholesterolemia, HDL-C is raised by approximately 4% to 10%. The percentage changes are greater in patients with low baseline levels, including those with the common combination of high triglycerides (TG) and low HDL-C. These effects do not appear to be dose-related although there is evidence that, with the exception of atorvastatin, the changes in HDL-C are proportional to reductions in apo B-containing lipoproteins. The most likely explanation is a reduced rate of cholesteryl ester transfer protein (CETP)-mediated flow of cholesterol from HDL. There is some evidence that the statin effects on HDL reduce progression of atherosclerosis and risk of cardiovascular disease independently of reductions in LDL. CONCLUSION Statins cause modest increases in HDL-C and apo A-I probably mediated by reductions in CETP activity. It is plausible that such changes independently contribute to the cardiovascular benefits of the statin class but more studies are needed to further explore this possibility.
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Affiliation(s)
- Fergus McTaggart
- Clinical Development, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK.
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20
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Carnemolla R, Ren X, Biswas TK, Meredith SC, Reardon CA, Wang J, Getz GS. The specific amino acid sequence between helices 7 and 8 influences the binding specificity of human apolipoprotein A-I for high density lipoprotein (HDL) subclasses: a potential for HDL preferential generation. J Biol Chem 2008; 283:15779-88. [PMID: 18385132 PMCID: PMC2414305 DOI: 10.1074/jbc.m710244200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 04/01/2008] [Indexed: 02/02/2023] Open
Abstract
Humans have two major high density lipoprotein (HDL) sub-fractions, HDL(2) and HDL(3), whereas mice have a monodisperse HDL profile. Epidemiological evidence has suggested that HDL(2) is more atheroprotective; however, currently there is no direct experimental evidence to support this postulate. The amino acid sequence of apoA-I is a primary determinant of HDL subclass formation. The majority of the alpha-helical repeats in human apoA-I are proline-punctuated. A notable exception is the boundary between helices 7 and 8, which is located in the transitional segment between the stable N-terminal domain and the C-terminal hydrophobic domain. In this study we ask whether the substitution of a proline-containing sequence (PCS) separating other helices in human apoA-I for the non-proline-containing sequence (NPCS) between helices 7 and 8 (residues 184-190) influences HDL subclass association. The human apoA-I mutant with PCS2 replacing NPCS preferentially bound to HDL(2). In contrast, the mutant where PCS3 replaced NPCS preferentially associated with HDL(3). Thus, the specific amino acid sequence between helices 7 and 8 influences HDL subclass association. The wild-type and mutant proteins exhibited similar physicochemical properties except that the two mutants displayed greater lipid-associated stability versus wild-type human apoA-I. These results focus new attention on the influence of the boundary between helices 7 and 8 on the properties of apoA-I. The expression of these mutants in mice may result in the preferential generation of HDL(2) or HDL(3) and allow us to examine experimentally the anti-atherogenicity of the HDL subclasses.
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Affiliation(s)
- Ronald Carnemolla
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Xuefeng Ren
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Tapan K. Biswas
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Stephen C. Meredith
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Catherine A. Reardon
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Jianjun Wang
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
| | - Godfrey S. Getz
- Department of Pathology and the
Committee of Molecular Metabolism and Nutrition,
The University of Chicago, Chicago, Illinois 60637 and the
Department of Biochemistry and Molecular
Biology, Wayne State University, Detroit, Michigan 48201
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21
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Fujita H, Okada T, Inami I, Makimoto M, Hosono S, Minato M, Takahashi S, Mugishima H, Yamamoto T. Heterogeneity of high-density lipoprotein in cord blood and its postnatal change. Clin Chim Acta 2008; 389:93-7. [DOI: 10.1016/j.cca.2007.11.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 10/23/2007] [Accepted: 11/29/2007] [Indexed: 10/22/2022]
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22
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Jayaraman S, Gantz DL, Gursky O. Effects of protein oxidation on the structure and stability of model discoidal high-density lipoproteins. Biochemistry 2008; 47:3875-82. [PMID: 18302337 DOI: 10.1021/bi7023783] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
High-density lipoproteins (HDLs) prevent atherosclerosis by removing cholesterol from macrophages and by providing antioxidants for low-density lipoproteins. Oxidation of HDLs affects their functions via the complex mechanisms that involve multiple protein and lipid modifications. To differentiate between the roles of oxidative modifications in HDL proteins and lipids, we analyzed the effects of selective protein oxidation by hypochlorite (HOCl) on the structure, stability, and remodeling of discoidal HDLs reconstituted from human apolipoproteins (A-I, A-II, or C-I) and phosphatidylcholines. Gel electrophoresis and electron microscopy revealed that, at ambient temperatures, protein oxidation in discoidal complexes promotes their remodeling into larger and smaller particles. Thermal denaturation monitored by far-UV circular dichroism and light scattering in melting and kinetic experiments shows that protein oxidation destabilizes discoidal lipoproteins and accelerates protein unfolding, dissociation, and lipoprotein fusion. This is likely due to the reduced affinity of the protein for lipid resulting from oxidation of Met and aromatic residues in the lipid-binding faces of amphipathic alpha-helices and to apolipoprotein cross-linking into dimers and trimers on the particle surface. We conclude that protein oxidation destabilizes HDL disk assembly and accelerates its remodeling and fusion. This result, which is not limited to model discoidal but also extends to plasma spherical HDL, helps explain the complex effects of oxidation on plasma lipoproteins.
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Affiliation(s)
- Shobini Jayaraman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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23
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Tocharoentanaphol C, Promso S, Zelenika D, Lowhnoo T, Tongsima S, Sura T, Chantratita W, Matsuda F, Mooney S, Sakuntabhai A. Evaluation of resequencing on number of tag SNPs of 13 atherosclerosis-related genes in Thai population. J Hum Genet 2007; 53:74-86. [PMID: 18043865 DOI: 10.1007/s10038-007-0220-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Accepted: 10/29/2007] [Indexed: 11/26/2022]
Abstract
In the candidate gene approach, information about the distribution of single nucleotide polymorphisms (SNPs) is a crucial requirement for choosing efficient markers necessary for a case-control association study. To obtain such information, we discovered SNPs in 13 genes related to atherosclerosis by resequencing exon-flanking regions of 32 healthy Thai individuals. In total, 194 polymorphisms were identified, 184 of them SNPs, four insertions, and the rest deletions. Fifty-nine of the SNPs were characterized as novel polymorphisms, and these accounted for 30% of the identified SNPs. Comparing allele frequency distributions of the Thai population with other Asian populations shows similar patterns. In contrast, a low correlation pattern (r = 0.521) was found when comparing with either Caucasian or African populations. However, some rare alleles (rs11574541 and rs10874913) are found in the Thai population but not in other Asian populations. Most of the novel SNPs found were located outside the haplotype blocks generated by known SNPs in the Thai population. Only 5.77% of the novel SNPs lies in these defined haplotype blocks. The selection of haplotype-tagging SNPs shows that 8 of 13 genes benefited from the ethnic-specific genotype information. That is, when at least one novel SNP was present, the tagging SNPs chosen were altered. Functional prediction of 16 nonsynonymous SNPs (nsSNPs) by three different algorithm tools demonstrated that five nsSNPs possibly alter their corresponding protein functions. These results provide necessary information for conducting further genetic association studies involving the Thai population and demonstrate that resequencing of candidate genes provides more complete information for full genetic studies.
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Affiliation(s)
- Chintana Tocharoentanaphol
- Centre National de Génotypage, 2 rue Gaston Crémieux, CP 5721, 91057, Evry Cedex, France.
- Chulabhorn Cancer Centre, Viphavadee-Rangsit road, Laksi, Bangkok, 10120, Thailand.
| | - Somying Promso
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
- Center for Computational Biology and Bioinformatics, Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Dianna Zelenika
- Centre National de Génotypage, 2 rue Gaston Crémieux, CP 5721, 91057, Evry Cedex, France
| | - Tassanee Lowhnoo
- Centre National de Génotypage, 2 rue Gaston Crémieux, CP 5721, 91057, Evry Cedex, France
- Research center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
| | - Sissades Tongsima
- National Center for Genetic Engineering and Biotechnology, Pathumthani, Thailand
| | - Thanyachai Sura
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
| | - Wasun Chantratita
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
| | - Fumihiko Matsuda
- Centre National de Génotypage, 2 rue Gaston Crémieux, CP 5721, 91057, Evry Cedex, France
| | - Sean Mooney
- Center for Computational Biology and Bioinformatics, Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Anavaj Sakuntabhai
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
- Laboratoire de Génétique de la réponse aux infections chez l'homme, Institut Pasteur, 75724, Paris Cedex 15, France
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24
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McKenney JM. Effect of drugs on high-density lipoprotein. J Clin Lipidol 2007; 1:74-87. [DOI: 10.1016/j.jacl.2007.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Accepted: 01/29/2007] [Indexed: 10/20/2022]
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Abstract
PURPOSE OF REVIEW The relationship between the concentration of high-density lipoprotein cholesterol and their protective function is addressed. RECENT FINDINGS Strong epidemiologic evidence indicates that the concentration of high-density lipoproteins is a powerful inverse predictor of cardiovascular risk. This is consistent with the fact that high levels of high-density lipoprotein are generally associated with an increased concentration of large high-density lipoprotein particles that are now known to be the preferred acceptors of cholesterol released from macrophages via the adenosine triphosphate-binding cassette A1 pathway. Some of the protective activity, however, of high-density lipoproteins may reflect functions of specific subpopulations or variations in the 'quality' of high-density lipoprotein particles and may be unrelated to the concentration of the total high-density lipoprotein fraction. This review summarizes the cardiovascular protective role of high-density lipoproteins and addresses how the concentration and antiatherogenic activity of high-density lipoproteins are related. SUMMARY Some of the protective functions of high-density lipoprotein are closely related to the simple concentration of high-density lipoproteins; others may not be related. Given the current high level of interest in therapies that raise the concentration of high-density lipoprotein, it is essential to conduct further research to identify precisely how high-density lipoproteins protect.
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26
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Brown CM, Rea TJ, Hamon SC, Hixson JE, Boerwinkle E, Clark AG, Sing CF. The contribution of individual and pairwise combinations of SNPs in the APOA1 and APOC3 genes to interindividual HDL-C variability. J Mol Med (Berl) 2006; 84:561-72. [PMID: 16705465 PMCID: PMC1698872 DOI: 10.1007/s00109-005-0037-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Accepted: 11/17/2005] [Indexed: 02/05/2023]
Abstract
Apolipoproteins (apo) A-I and C-III are components of high-density lipoprotein-cholesterol (HDL-C), a quantitative trait negatively correlated with risk of cardiovascular disease (CVD). We analyzed the contribution of individual and pairwise combinations of single nucleotide polymorphisms (SNPs) in the APOA1/APOC3 genes to HDL-C variability to evaluate (1) consistency of published single-SNP studies with our single-SNP analyses; (2) consistency of single-SNP and two-SNP phenotype-genotype relationships across race-, gender-, and geographical location-dependent contexts; and (3) the contribution of single SNPs and pairs of SNPs to variability beyond that explained by plasma apo A-I concentration. We analyzed 45 SNPs in 3,831 young African-American (N=1,858) and European-American (N=1,973) females and males ascertained by the Coronary Artery Risk Development in Young Adults (CARDIA) study. We found three SNPs that significantly impact HDL-C variability in both the literature and the CARDIA sample. Single-SNP analyses identified only one of five significant HDL-C SNP genotype relationships in the CARDIA study that was consistent across all race-, gender-, and geographical location-dependent contexts. The other four were consistent across geographical locations for a particular race-gender context. The portion of total phenotypic variance explained by single-SNP genotypes and genotypes defined by pairs of SNPs was less than 3%, an amount that is miniscule compared to the contribution explained by variability in plasma apo A-I concentration. Our findings illustrate the impact of context-dependence on SNP selection for prediction of CVD risk factor variability.
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Affiliation(s)
- C. M. Brown
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - T. J. Rea
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - S. C. Hamon
- Laboratory of Statistical Genetics, Rockefeller University, New York, NY 10021, USA
| | - J. E. Hixson
- Human Genetics Center, University of Texas Health Science Center, Houston, TX 77030, USA
| | - E. Boerwinkle
- Human Genetics Center, University of Texas Health Science Center, Houston, TX 77030, USA
| | - A. G. Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - C. F. Sing
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
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27
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Gorshkova IN, Liu T, Kan HY, Chroni A, Zannis VI, Atkinson D. Structure and stability of apolipoprotein a-I in solution and in discoidal high-density lipoprotein probed by double charge ablation and deletion mutation. Biochemistry 2006; 45:1242-54. [PMID: 16430220 PMCID: PMC2532493 DOI: 10.1021/bi051669r] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To identify residues and segments in the central region of apolipoprotein A-I (apoA-I) that are important for the protein structure and stability, we studied the effects of four double charge ablations, D102A/D103A, E110A/E111A, R116V/K118A, and R160V/H162A, and two deletion mutations, Delta(61-78) and Delta(121-142), on the conformation and stability of apoA-I in the lipid-free state and in reconstituted discoidal phospholipid-cholesterol-apoA-I particles (rHDL). The findings suggest that D102/D103 and E110/E111 located in helix 4 and segment(s) between residues 61 and 78 are involved in maintenance of the conformation and stability of apoA-I in both the lipid-free state and in rHDL. R116/K118 located in helix 4 are essential for the conformation and stabilization of apoA-I in rHDL but not vital for the lipid-free state of the protein. The R160V/H162A substitutions in helix 6 lead to a less compact tertiary structure of lipid-free apoA-I without notable effects on the lipid-free or lipid-bound secondary conformation, suggesting involvement of R160/H162 in important interhelical interactions. The results on the Delta(121-142) mutant, together with our earlier findings, suggest disordered structure of a major segment between residues 121 and 143, likely including residues 131-143, in lipid-free apoA-I. Our findings provide the first experimental evidence for stabilization of rHDL by specific electrostatic interhelical interactions, in agreement with the double belt model. The effects of alterations in the conformation and stability of the apoA-I mutants on in vitro and in vivo functions of apoA-I and lipid homeostasis are discussed.
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Affiliation(s)
- Irina N Gorshkova
- Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany Street, Boston, Massachusetts 02118, USA.
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28
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Long S, Tian Y, Zhang R, Yang L, Xu Y, Jia L, Fu M. Relationship between plasma HDL subclasses distribution and lipoprotein lipase gene HindIII polymorphism in hyperlipidemia. Clin Chim Acta 2006; 366:316-21. [PMID: 16364275 DOI: 10.1016/j.cca.2005.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2005] [Revised: 11/09/2005] [Accepted: 11/12/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Different high-density lipoprotein (HDL) subclasses have distinct but interrelated metabolic functions. HDL directly influences the atherogenic process, and changes in HDL subclasses distribution may be related to the incidence and prevalence of atherosclerosis. Lipoprotein lipase (LPL) is an important enzyme for hydrolysis of triglyceride-rich lipoproteins, and its activity is positively correlated with the plasma HDL cholesterol level. LPL gene HindIII polymorphism has been found associated with variations in lipid levels, but the impact on HDL subclasses distribution is less clearly established. METHODS The relative apolipoprotein (apo) A-I contents (% apoA-I) of plasma HDL subclasses were determined by two-dimensional gel electrophoresis coupled with immunodetection and LPL gene HindIII polymorphism was assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 173 hyperlipidemic and 155 normolipidemic subjects. RESULTS The frequencies of 495TT genotype and allele T were the highest both in the hyperlipidemic and control groups. Compared with the control group, the frequency of 495TT genotype was higher, while the frequencies of 495TG and 495GG genotypes were significantly lower (P<0.05) in the hyperlipidemic group. Two-dimensional gel electrophoresis and immunodetection showed that HDL subclasses distribution was altered in hyperlipidemia, and had a general shift toward smaller size. Compared with the control group, the hyperlipidemic group had significantly higher relative apoA-I contents of prebeta1-HDL, prebeta2-HDL, HDL3b and HDL3a (P<0.05) and lower HDL2a and HDL2b levels (P<0.001). In the hyperlipidemic group, allele T carriers' frequency was higher than that in the control group (P<0.05), and the genotype of 495TT showed higher levels of plasma TG, apoB100, TG/HDL-C ratio, relative apoA-I contents of prebeta1-HDL, HDL3b and lower HDL2a, HDL2b compared with that of the 495GG genotype subgroup (P<0.05). In the control group, the genotype of 495TT had higher plasma TG, HDL3c and lower HDL2a compared with that of 495GG subgroup (P<0.05). CONCLUSIONS The 495TT genotype of LPL gene HindIII polymorphism was associated with changes of HDL subclasses distribution in Chinese population with hyperlipidemia. The particle size of HDL shifted toward smaller, which, in turn, indicated that RCT might be weakened and HDL maturation might be abnormal in hyperlipidemic subjects with 495TT genotype.
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Affiliation(s)
- Shiyin Long
- Apolipoprotein Research Unit, Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, 610041 Sichuan, PR China
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29
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Mutch DM, Fauconnot L, Grigorov M, Fay LB. Putting the 'Ome' in lipid metabolism. BIOTECHNOLOGY ANNUAL REVIEW 2006; 12:67-84. [PMID: 17045192 DOI: 10.1016/s1387-2656(06)12003-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The recognition that altered lipid metabolism underlies many metabolic disorders challenging Western society highlights the importance of this metabolomic subset, herein referred to as the lipidome. Although comprehensive lipid analyses are not a recent concept, the novelty of a lipidomic approach lies with the application of robust statistical algorithms to highlight subtle, yet significant, changes in a population of lipid molecules. First-generation lipidomic studies have demonstrated the sensitivity of interpreting quantitative datasets with computational software; however, the innate power of comprehensive lipid profiling is often not exploited, as robust statistical models are not routinely utilized. Therefore, the current review aims to briefly describe the current technologies suitable for comprehensive lipid analysis, outline innovative mathematical models that have the ability to reveal subtle changes in metabolism, which will ameliorate our understanding of lipid biochemistry, and demonstrate the biological revelations found through lipidomic approaches and their potential implications for health management.
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Affiliation(s)
- David M Mutch
- Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland
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Meyers CD, Kashyap ML. Pharmacologic augmentation of high-density lipoproteins: mechanisms of currently available and emerging therapies. Curr Opin Cardiol 2005; 20:307-12. [PMID: 15956828 DOI: 10.1097/01.hco.0000167718.30076.24] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW With the limited effects of low-density lipoprotein-based lipid intervention, more attention is being paid to drugs that augment or mimic high-density lipoprotein's beneficial effects. A thorough understanding of the anti-atherogenic effects of high-density lipoprotein, and the mechanisms of existing or emerging high-density lipoprotein-based therapies, is essential for rational strategy for the prevention of cardiovascular disease. RECENT FINDINGS High-density lipoprotein mediates its beneficial effects through reverse cholesterol transport and direct anti-inflammatory effects of apolipoprotein AI and other component parts. Currently available drugs increase high-density lipoprotein-C through increasing apoAI synthesis (statins, fibrates) and decreasing apolipoprotein AI catabolism (niacin). Cholesteryl ester transfer protein inhibitors dramatically raise high-density lipoprotein-C, but clinical data are still required to verify their cardioprotective effects. Novel therapies such as apolipoprotein AImilano, apolipoprotein AI mimetic peptide, and exogenous phospholipids show tremendous promise as treatments for atherosclerosis. SUMMARY High-density lipoprotein and its defining functional protein apoAI prevent atherosclerosis through reverse cholesterol transport and other direct effects. Research has led to the development of novel therapies that increase high-density lipoprotein-C or that mimic direct anti-atherogenic effects of apolipoprotein AI. As these emerging therapies find a place in clinical medicine, we can anticipate preventing a much higher degree of cardiovascular events.
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Affiliation(s)
- C Daniel Meyers
- Atherosclerosis Research Center, VA Long Beach Healthcare System, 5901 East 7th Street (11-1111), Long Beach, CA 90822, USA
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Lee CY, Lesimple A, Larsen A, Mamer O, Genest J. ESI-MS quantitation of increased sphingomyelin in Niemann-Pick disease type B HDL. J Lipid Res 2005; 46:1213-28. [PMID: 15741650 DOI: 10.1194/jlr.m500011-jlr200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
HDLs have been proposed to have antiatherogenic properties because of their role in reverse cholesterol transport as lipid acceptors. To elucidate the phospholipid profile of these particles, we used electrospray ionization mass spectrometry to examine the phosphatidylcholine (PC) and sphingomyelin (SM) composition of HDLs purified from plasma and nascently generated in vitro from fibroblasts. We also quantitatively compared the phospholipids present in these lipoproteins between normal and Niemann-Pick disease type B (NPD-B) subjects characterized by sphingomyelinase (SMase) deficiency. We demonstrated that plasma HDLs from NPD-B were significantly enriched in SM by an average of 28%, particularly the palmitoyl SM (with an increase of 95%), which accounted for approximately 25-44% of total SM molecular species. Similarly, we observed an increase of approximately 63% in total SM levels in nascent HDLs prepared from NPD-B fibroblasts. Although PC levels in nascent HDLs were comparable between control and NPD-B cells, there was a 95% increase in total PC levels similar to that of SM in plasma HDLs extracted from NPD-B subjects. These data provide insight into the structure of HDLs and identify potential new roles for SMase in lipoprotein metabolism.
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Affiliation(s)
- Ching Yin Lee
- Cardiovascular Genetics Laboratory, McGill University, Montréal, Canada
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Davidson WS, Silva RAGD. Apolipoprotein structural organization in high density lipoproteins: belts, bundles, hinges and hairpins. Curr Opin Lipidol 2005; 16:295-300. [PMID: 15891390 DOI: 10.1097/01.mol.0000169349.38321.ad] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW To summarize recent advances towards an understanding of the three-dimensional structures of the apolipoprotein components of HDL with a specific focus on high resolution models of apolipoprotein A-I. RECENT FINDINGS Since the primary sequence was first reported, various models have been advanced for the structure of apolipoprotein A-I, the major protein constituent of HDL, in its lipid-free and lipid-bound forms. Unfortunately, the generation of experimental data capable of distinguishing among the competing models has lagged far behind. However, recent experimental strategies, including X-ray crystallography, applications of resonance energy transfer and mass spectrometry, have combined with sophisticated theoretical approaches to develop three-dimensional structural models of apolipoprotein A-I with previously unavailable resolution. SUMMARY The recent synergy of sophisticated computer modeling techniques with hard experimental data has generated new models for apolipoprotein A-I in certain subclasses of HDL produced in vitro. The challenge now is to adapt and test these models in the more complex forms of HDL isolated directly from human plasma.
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Affiliation(s)
- W Sean Davidson
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio 45237-0507, USA.
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Mach F. Inflammation is a crucial feature of atherosclerosis and a potential target to reduce cardiovascular events. Handb Exp Pharmacol 2005:697-722. [PMID: 16596820 DOI: 10.1007/3-540-27661-0_26] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Contrary to popular opinion, atherosclerosis is not a disease unique to modern civilization. In fact, atherosclerotic lesions have been found in the arteries of mummies dating back to 1,500 B.C., and yet our understanding of this complex process is still evolving. A fusion of basic science advances and clinical research findings has radically altered our traditional concepts about the pathogenesis and treatment of the clinical complications of atherosclerosis. Most physicians previously regarded the artery as a being merely a blood conduit that became encrusted with lipid detritus as part of the aging process. Modern-day treatment of atherosclerosis has arisen primarily from an understanding of the epidemiology of the disease rather than its pathophysiology, in that risk factors have traditionally been targeted. Our concepts of atherogenesis have evolved from vague ideas of inevitable degeneration to a much better defined scenario of molecular and cellular events. As we enhance our understanding of its fundamental mechanism, we can begin to approach atherogenesis as a modifiable rather than ineluctable process. Indeed, as we recognize now that inflammation plays a pivotal role in the process of atherosclerosis, it is noteworthy to evaluate the effect of modern therapies on this facet of the disease.
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Affiliation(s)
- F Mach
- Division of Cardiology, Department of Medicine, University Hospital Geneva, Switzerland.
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