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Kalayci A, Gibson CM, Ridker PM, Wright SD, Kingwell BA, Korjian S, Chi G, Lee JJ, Tricoci P, Kazmi SH, Fitzgerald C, Shaunik A, Berman G, Duffy D, Libby P. ApoA-I Infusion Therapies Following Acute Coronary Syndrome: Past, Present, and Future. Curr Atheroscler Rep 2022; 24:585-597. [PMID: 35524914 PMCID: PMC9236992 DOI: 10.1007/s11883-022-01025-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2022] [Indexed: 11/24/2022]
Abstract
PURPOSE OF REVIEW The elevated adverse cardiovascular event rate among patients with low high-density lipoprotein cholesterol (HDL-C) formed the basis for the hypothesis that elevating HDL-C would reduce those events. Attempts to raise endogenous HDL-C levels, however, have consistently failed to show improvements in cardiovascular outcomes. However, steady-state HDL-C concentration does not reflect the function of this complex family of particles. Indeed, HDL functions correlate only weakly with serum HDL-C concentration. Thus, the field has pivoted from simply raising the quantity of HDL-C to a focus on improving the putative anti-atherosclerotic functions of HDL particles. Such functions include the ability of HDL to promote the efflux of cholesterol from cholesterol-laden macrophages. Apolipoprotein A-I (apoA-I), the signature apoprotein of HDL, may facilitate the removal of cholesterol from atherosclerotic plaque, reduce the lesional lipid content and might thus stabilize vulnerable plaques, thereby reducing the risk of cardiac events. Infusion of preparations of apoA-I may improve cholesterol efflux capacity (CEC). This review summarizes the development of apoA-I therapies, compares their structural and functional properties and discusses the findings of previous studies including their limitations, and how CSL112, currently being tested in a phase III trial, may overcome these challenges. RECENT FINDINGS Three major ApoA-I-based approaches (MDCO-216, CER-001, and CSL111/CSL112) have aimed to enhance reverse cholesterol transport. These three therapies differ considerably in both lipid and protein composition. MDCO-216 contains recombinant ApoA-I Milano, CER-001 contains recombinant wild-type human ApoA-I, and CSL111/CSL112 contains native ApoA-I isolated from human plasma. Two of the three agents studied to date (apoA-1 Milano and CER-001) have undergone evaluation by intravascular ultrasound imaging, a technique that gauges lesion volume well but does not assess other important variables that may relate to clinical outcomes. ApoA-1 Milano and CER-001 reduce lecithin-cholesterol acyltransferase (LCAT) activity, potentially impairing the function of HDL in reverse cholesterol transport. Furthermore, apoA-I Milano can compete with and alter the function of the recipient's endogenous apoA-I. In contrast to these agents, CSL112, a particle formulated using human plasma apoA-I and phosphatidylcholine, increases LCAT activity and does not lead to the malfunction of endogenous apoA-I. CSL112 robustly increases cholesterol efflux, promotes reverse cholesterol transport, and now is being tested in a phase III clinical trial. Phase II-b studies of MDCO-216 and CER-001 failed to produce a significant reduction in coronary plaque volume as assessed by IVUS. However, the investigation to determine whether the direct infusion of a reconstituted apoA-I reduces post-myocardial infarction coronary events is being tested using CSL112, which is dosed at a higher level than MDCO-216 and CER-001 and has more favorable pharmacodynamics.
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Affiliation(s)
- Arzu Kalayci
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - C Michael Gibson
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Baim Institute for Clinical Research, Boston, MA, USA
| | - Paul M Ridker
- Center for Cardiovascular Disease Prevention, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | - Serge Korjian
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Gerald Chi
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Jane J Lee
- Baim Institute for Clinical Research, Boston, MA, USA
| | | | - S Hassan Kazmi
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Clara Fitzgerald
- Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | | | - Gail Berman
- Paratek Pharmaceuticals, King of Prussia, PA, USA
| | | | - Peter Libby
- Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA.
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Abstract
Apolipoproteins are important structural components of plasma lipoproteins that influence vascular biology and atherosclerotic disease pathophysiology by regulating lipoprotein metabolism. Clinically important apolipoproteins related to lipid metabolism and atherogenesis include apolipoprotein B-100, apolipoprotein B-48, apolipoprotein A-I, apolipoprotein C-II, apolipoprotein C-III, apolipoprotein E and apolipoprotein(a). Apolipoprotein B-100 is the major structural component of VLDL, IDL, LDL and lipoprotein(a). Apolipoprotein B-48 is a truncated isoform of apolipoprotein B-100 that forms the backbone of chylomicrons. Apolipoprotein A-I provides the scaffolding for lipidation of HDL and has an important role in reverse cholesterol transport. Apolipoproteins C-II, apolipoprotein C-III and apolipoprotein E are involved in triglyceride-rich lipoprotein metabolism. Apolipoprotein(a) covalently binds to apolipoprotein B-100 to form lipoprotein(a). In this Review, we discuss the mechanisms by which these apolipoproteins regulate lipoprotein metabolism and thereby influence vascular biology and atherosclerotic disease. Advances in the understanding of apolipoprotein biology and their translation into therapeutic agents to reduce the risk of cardiovascular disease are also highlighted.
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Castaño D, Rattanasopa C, Monteiro-Cardoso VF, Corlianò M, Liu Y, Zhong S, Rusu M, Liehn EA, Singaraja RR. Lipid efflux mechanisms, relation to disease and potential therapeutic aspects. Adv Drug Deliv Rev 2020; 159:54-93. [PMID: 32423566 DOI: 10.1016/j.addr.2020.04.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 04/29/2020] [Accepted: 04/30/2020] [Indexed: 02/06/2023]
Abstract
Lipids are hydrophobic and amphiphilic molecules involved in diverse functions such as membrane structure, energy metabolism, immunity, and signaling. However, altered intra-cellular lipid levels or composition can lead to metabolic and inflammatory dysfunction, as well as lipotoxicity. Thus, intra-cellular lipid homeostasis is tightly regulated by multiple mechanisms. Since most peripheral cells do not catabolize cholesterol, efflux (extra-cellular transport) of cholesterol is vital for lipid homeostasis. Defective efflux contributes to atherosclerotic plaque development, impaired β-cell insulin secretion, and neuropathology. Of these, defective lipid efflux in macrophages in the arterial walls leading to foam cell and atherosclerotic plaque formation has been the most well studied, likely because a leading global cause of death is cardiovascular disease. Circulating high density lipoprotein particles play critical roles as acceptors of effluxed cellular lipids, suggesting their importance in disease etiology. We review here mechanisms and pathways that modulate lipid efflux, the role of lipid efflux in disease etiology, and therapeutic options aimed at modulating this critical process.
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Fanni G, Rosato R, Gentile L, Anselmino M, Frea S, Ponzo V, Pellegrini M, Broglio F, Pivari F, De Ferrari GM, Ghigo E, Bo S. Is HDL cholesterol protective in patients with type 2 diabetes? A retrospective population-based cohort study. J Transl Med 2020; 18:189. [PMID: 32375888 PMCID: PMC7203837 DOI: 10.1186/s12967-020-02357-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/27/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The protective role of high HDL cholesterol levels against cardiovascular diseases has been recently questioned. Limited data are available on this specific topic in patients with type 2 diabetes mellitus (T2DM). We aimed to evaluate the association of HDL cholesterol concentrations with all-cause and cause-specific mortality in a historical cohort of T2DM patients with 14 years of follow-up. METHODS This is a retrospective population-based cohort study involving 2113 T2DM patients attending the Diabetic Clinic of Asti. Survival analyses were performed to assess hazard ratios for overall and specific-cause mortality by HDL cholesterol tertiles, using the middle HDL cholesterol tertile as a reference. RESULTS The mean age was 66 ± 11 years; 51.4% of patients had low HDL-cholesterol levels. After a 14-year follow-up, 973/2112 patients had died (46.1%). The HDL cholesterol tertile cut-off points were 37.5 and 47.5 mg/dL (males) and 41.5 and 52.0 mg/dL (females). No associations between lower and upper HDL cholesterol tertiles respectively and all-cause (HR = 1.12; 95% CI 0.96-1.32; HR = 1.11; 0.95-1.30), cardiovascular (HR = 0.97; 0.77-1.23; HR = 0.94; 0.75-1.18) or cancer (HR = 0.92; 0.67-1.25; HR = 0.89; 0.66-1.21) mortality were found. A significantly increased risk for infectious disease death was found both in the lower (HR = 2.62; 1.44-4.74) and the upper HDL-cholesterol tertiles (HR = 2.05; 1.09-3.85) when compared to the reference. Individuals in the upper tertile showed an increased risk for mortality due to diabetes-related causes (HR = 1.87; 1.10-3.15). CONCLUSIONS Our results corroborate the hypothesis that HDL cholesterol levels are nonprotective in T2DM patients. The U-shaped association between HDL-cholesterol levels and mortality associated with infectious diseases should be verified by further studies.
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Affiliation(s)
- Giovanni Fanni
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy
| | - Rosalba Rosato
- Department of Psychology, University of Turin, Turin, Italy
| | | | - Matteo Anselmino
- Cardiology Unit, Città della Salute e della Scienza Hospital and University of Turin, Turin, Italy
| | - Simone Frea
- Cardiology Unit, Città della Salute e della Scienza Hospital and University of Turin, Turin, Italy
| | - Valentina Ponzo
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy
| | - Marianna Pellegrini
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy
| | - Fabio Broglio
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy
| | - Francesca Pivari
- Department of Health Sciences, University of Milan, Milan, Italy
| | - Gaetano Maria De Ferrari
- Cardiology Unit, Città della Salute e della Scienza Hospital and University of Turin, Turin, Italy
| | - Ezio Ghigo
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy
| | - Simona Bo
- Department of Medical Sciences, University of Turin, Corso AM Dogliotti, 14 10126, Turin, To, Italy.
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Navdaev AV, Sborgi L, Wright SD, Didichenko SA. Nascent HDL (High-Density Lipoprotein) Discs Carry Cholesterol to HDL Spheres: Effects of HDL Particle Remodeling on Cholesterol Efflux. Arterioscler Thromb Vasc Biol 2020; 40:1182-1194. [PMID: 32131613 PMCID: PMC7176342 DOI: 10.1161/atvbaha.120.313906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To characterize the fate of protein and lipid in nascent HDL (high-density lipoprotein) in plasma and explore the role of interaction between nascent HDL and mature HDL in promoting ABCA1 (ATP-binding cassette transporter 1)-dependent cholesterol efflux. Approach and Results: Two discoidal species, nascent HDL produced by RAW264.7 cells expressing ABCA1 (LpA-I [apo AI containing particles formed by incubating ABCA1-expressing cells with apo AI]), and CSL112, human apo AI (apolipoprotein AI) reconstituted with phospholipids, were used for in vitro incubations with human plasma or purified spherical plasma HDL. Fluorescent labeling and biotinylation of HDL were employed to follow the redistribution of cholesterol and apo AI, cholesterol efflux was measured using cholesterol-loaded cells. We show that both nascent LpA-I and CSL112 can rapidly fuse with spherical HDL. Redistribution of the apo AI molecules and cholesterol after particle fusion leads to the formation of (1) enlarged, remodeled, lipid-rich HDL particles carrying lipid and apo AI from LpA-I and (2) lipid-poor apo AI particles carrying apo AI from both discs and spheres. The interaction of discs and spheres led to a greater than additive elevation of ABCA1-dependent cholesterol efflux. CONCLUSIONS These data demonstrate that although newly formed discs are relatively poor substrates for ABCA1, they can interact with spheres to produce lipid-poor apo AI, a much better substrate for ABCA1. Because the lipid-poor apo AI generated in this interaction can itself become discoid by the action of ABCA1, cycles of cholesterol efflux and disc-sphere fusion may result in net ABCA1-dependent transfer of cholesterol from cells to HDL spheres. This process may be of particular importance in atherosclerotic plaque where cholesterol acceptors may be limiting.
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Affiliation(s)
- Alexei V Navdaev
- From the CSL Behring AG, Bern, Switzerland (A.V.N., L.S., S.A.D.)
| | - Lorenzo Sborgi
- From the CSL Behring AG, Bern, Switzerland (A.V.N., L.S., S.A.D.)
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Sirtori CR, Ruscica M, Calabresi L, Chiesa G, Giovannoni R, Badimon JJ. HDL therapy today: from atherosclerosis, to stent compatibility to heart failure. Ann Med 2019; 51:345-359. [PMID: 31729238 PMCID: PMC7877888 DOI: 10.1080/07853890.2019.1694695] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Epidemiologically, high-density lipoprotein (HDL) cholesterol levels have been inversely associated to cardiovascular (CV) events, although a Mendelian Randomisation Study had failed to establish a clear causal role. Numerous atheroprotective mechanisms have been attributed to HDL, the main being the ability to promote cholesterol efflux from arterial walls; anti-inflammatory effects related to HDL ligands such as S1P (sphingosine-1-phosphate), resolvins and others have been recently identified. Experimental studies and early clinical investigations have indicated the potential of HDL to slow progression or induce regression of atherosclerosis. More recently, the availability of different HDL formulations, with different phospholipid moieties, has allowed to test other indications for HDL therapy. Positive reports have come from studies on coronary stent biocompatibility, where the use of HDL from different sources reduced arterial cell proliferation and thrombogenicity. The observation that low HDL-C levels may be associated with an enhanced risk of heart failure (HF) has also suggested that HDL therapy may be applied to this condition. HDL infusions or apoA-I gene transfer were able to reverse heart abnormalities, reduce diastolic resistance and improve cardiac metabolism. HDL therapy may be effective not only in atherosclerosis, but also in other conditions, of relevant impact on human health.Key messagesHigh-density lipoproteins have as a major activity that of removing excess cholesterol from tissues (particularly arteries).Knowledge on the activity of high-density lipoproteins on health have however significantly widened.HDL-therapy may help to improve stent biocompatibility and to reduce peripheral arterial resistance in heart failure.
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Affiliation(s)
- C R Sirtori
- Dyslipidemia Center, A.S.S.T. Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - M Ruscica
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - L Calabresi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - G Chiesa
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - R Giovannoni
- Department of Biology, University of Pisa, Pisa, Italy
| | - J J Badimon
- Mount Sinai Heart, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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7
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Khalil A, Kamtchueng Simo O, Ikhlef S, Berrougui H. The role of paraoxonase 1 in regulating high-density lipoprotein functionality during aging. Can J Physiol Pharmacol 2017; 95:1254-1262. [DOI: 10.1139/cjpp-2017-0117] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Pharmacological interventions to increase the concentration of high-density lipoprotein (HDL) have led to disappointing results and have contributed to the emergence of the concept of HDL functionality. The anti-atherogenic activity of HDLs can be explained by their functionality or quality. The capacity of HDLs to maintain cellular cholesterol homeostasis and to transport cholesterol from peripheral cells to the liver for elimination is one of their principal anti-atherogenic activities. However, HDLs possess several other attributes that contribute to their protective effect against cardiovascular diseases. HDL functionality is regulated by various proteins and lipids making up HDL particles. However, several studies investigated the role of paraoxonase 1 (PON1) and suggest a significant role of this protein in the regulation of the functionality of HDLs. Moreover, research on PON1 attracted much interest following several studies indicating that it is involved in cardiovascular protection. However, the mechanisms by which PON1 exerts these effects remain to be elucidated.
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Affiliation(s)
- Abdelouahed Khalil
- Research Centre on Aging, Sherbrooke, QC J1H 4C4, Canada
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| | | | - Souade Ikhlef
- Research Centre on Aging, Sherbrooke, QC J1H 4C4, Canada
| | - Hicham Berrougui
- Department of Biology, Polydisciplinary Faculty, University Sultan Moulay Slimane, BP 592, 23000 Beni Mellal, Morocco
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8
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Bisgaier CL, Ackermann R, Rea T, Rodrigueza WV, Hartman D. ApoA-IMilano phospholipid complex (ETC-216) infusion in human volunteers. Insights into the phenotypic characteristics of ApoA-IMilano carriers. Pharmacol Res 2016; 111:86-99. [DOI: 10.1016/j.phrs.2016.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 05/02/2016] [Accepted: 05/02/2016] [Indexed: 12/15/2022]
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9
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Abstract
Several recent reports have raised doubts about the atheroprotective role of high-density lipoprotein cholesterol (HDL-C). Nevertheless, a substantial body of work supports the validity of pharmacological interventions able to enhance HDL function, as opposed to raising HDL-C levels per se. In this article, we briefly review the development of pharmacological interventions that target apoA-I and HDL function as a means of reducing atherosclerotic risk: small molecule pharmaceuticals, small HDL mimetic peptides, and infusion of apoA-I-containing particles.
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10
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Abstract
The concept of lipoprotein mimetics was developed and extensively tested in the last three decades. Most lipoprotein mimetics were designed to recreate one or several functions of high-density lipoprotein (HDL) in the context of cardiovascular disease; however, the application of this approach is much broader. Lipoprotein mimetics should not just be seen as a set of compounds aimed at replenishing a deficiency or dysfunctionality of individual elements of lipoprotein metabolism but rather as a designer concept with remarkable flexibility and numerous applications in medicine and biology. In the present review, we discuss the fundamental design principles used to create lipoprotein mimetics, mechanisms of their action, medical indications and efficacy in animal models and human studies.
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11
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A novel ApoA-I truncation (ApoA-IMytilene) associated with decreased ApoA-I production. Atherosclerosis 2014; 235:470-6. [DOI: 10.1016/j.atherosclerosis.2014.05.935] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/16/2014] [Accepted: 05/20/2014] [Indexed: 11/23/2022]
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12
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Calabresi L, Gomaraschi M, Simonelli S, Bernini F, Franceschini G. HDL and atherosclerosis: Insights from inherited HDL disorders. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:13-8. [PMID: 25068410 DOI: 10.1016/j.bbalip.2014.07.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/14/2014] [Accepted: 07/20/2014] [Indexed: 01/25/2023]
Abstract
Plasma high density lipoproteins (HDL) comprise a highly heterogeneous family of lipoprotein particles, differing in density, size, surface charge, and lipid and protein composition. Epidemiological studies have shown that plasma HDL level inversely correlates with atherosclerotic cardiovascular disease. The most relevant atheroprotective function of HDL is to promote the removal of cholesterol from macrophages within the arterial wall and deliver it to the liver for excretion in a process called reverse cholesterol transport. In addition, HDLs can contribute to the maintenance of endothelial cell homeostasis and have potent antioxidant properties. It has been long suggested that individual HDL subclasses may differ in terms of their functional properties, but which one is the good particle remains to be defined. Inherited HDL disorders are rare monogenic diseases due to mutations in genes encoding proteins involved in HDL metabolism. These disorders are not only characterized by extremely low or high plasma HDL levels but also by an abnormal HDL subclass distribution, and thus represent a unique tool to understand the relationship between plasma HDL concentration, HDL function, and HDL-mediated atheroprotection. This article is part of a Special Issue entitled Linking transcription to physiology in lipodomics.
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Affiliation(s)
- Laura Calabresi
- Centro Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy.
| | - Monica Gomaraschi
- Centro Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Sara Simonelli
- Centro Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Franco Bernini
- Department of Pharmacy, University of Parma, Parma, Italy
| | - Guido Franceschini
- Centro Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
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13
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Karavia EA, Zvintzou E, Petropoulou PI, Xepapadaki E, Constantinou C, Kypreos KE. HDL quality and functionality: what can proteins and genes predict? Expert Rev Cardiovasc Ther 2014; 12:521-32. [DOI: 10.1586/14779072.2014.896741] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Abstract
Cardiovascular disease (CVD) is the leading cause of death globally. For close to four decades, we have known that high density lipoprotein (HDL) levels are inversely correlated with the risk of CVD. HDL is a complex particle that consists of proteins, phospholipids, and cholesterol and has the ability to carry micro-RNAs. HDL is constantly undergoing remodelling throughout its life-span and carries out many functions. This review summarizes many of the different aspects of HDL from its assembly, the receptors it interacts with, along with the functions it performs and how it can be altered in disease. While HDL is a key cholesterol efflux particle, this review highlights the many other important functions of HDL in the innate immune system and details the potential therapeutic uses of HDL outside of CVD.
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15
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Abstract
PURPOSE OF REVIEW New therapeutic strategies are needed for the rapid stabilization of acute coronary syndrome (ACS) patients by treating nonculprit lesions. Reconstituted HDL (rHDL), which is apoA-I combined with phospholipids, is currently being tested in clinical trials for this purpose and is the subject of this review. RECENT FINDINGS At least four different formulations (SRC-rHDL, CSL-111, CSL-112 and ETC-216) have been tested in clinical trials. The various rHDL preparations have been shown to be effective in the rapid mobilization of excess cholesterol from cells and in regressing atherosclerotic plaques in animal models. Two of the rHDL agents, namely ETC-216 and CSL-111, have been shown to be effective after only a few treatments in reducing plaque volume in ACS patients, as assessed by intravascular ultrasound, but no clinical trials assessing clinical endpoints have yet been completed. SUMMARY rHDL is a promising new potential therapy for ACS patients, but much work remains to be done, and there are many unresolved questions. Progress in developing rHDL into a therapy will depend on improving our understanding of their mechanism of action, determining the optimum formulation and delivery and how to monitor rHDL therapy.
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Affiliation(s)
- Brian R Krause
- aAlphaCore Pharma, Ann Arbor, Michigan bLipoprotein Metabolism Section, Cardiopulmonary Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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16
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Gursky O, Jones MK, Mei X, Segrest JP, Atkinson D. Structural basis for distinct functions of the naturally occurring Cys mutants of human apolipoprotein A-I. J Lipid Res 2013; 54:3244-57. [PMID: 24038317 DOI: 10.1194/jlr.r037911] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
HDL removes cell cholesterol and protects against atherosclerosis. ApoA-I provides a flexible structural scaffold and an important functional ligand on the HDL surface. We propose structural models for apoA-I(Milano) (R173C) and apoA-I(Paris) (R151C) mutants that show high cardioprotection despite low HDL levels. Previous studies established that two apoA-I molecules encircle HDL in an antiparallel, helical double-belt conformation. Recently, we solved the atomic structure of lipid-free Δ(185-243)apoA-I and proposed a conformational ensemble for apoA-I(WT) on HDL. Here we modify this ensemble to understand how intermolecular disulfides involving C173 or C151 influence protein conformation. The double-belt conformations are modified by belt rotation, main-chain unhinging around Gly, and Pro-induced helical bending, and they are verified by comparison with previous experimental studies and by molecular dynamics simulations of apoA-I(Milano) homodimer. In our models, the molecular termini repack on various-sized HDL, while packing around helix-5 in apoA-I(WT), helix-6 in apoA-I(Paris), or helix-7 in apoA-I(Milano) homodimer is largely conserved. We propose how the disulfide-induced constraints alter the protein conformation and facilitate dissociation of the C-terminal segment from HDL to recruit additional lipid. Our models unify previous studies of apoA-I(Milano) and demonstrate how the mutational effects propagate to the molecular termini, altering their conformations, dynamics, and function.
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Affiliation(s)
- Olga Gursky
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
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17
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Kempen HJ, Gomaraschi M, Bellibas SE, Plassmann S, Zerler B, Collins HL, Adelman SJ, Calabresi L, Wijngaard PLJ. Effect of repeated apoA-IMilano/POPC infusion on lipids, (apo)lipoproteins, and serum cholesterol efflux capacity in cynomolgus monkeys. J Lipid Res 2013; 54:2341-53. [PMID: 23828780 DOI: 10.1194/jlr.m033779] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
MDCO-216, a complex of dimeric recombinant apoA-IMilano (apoA-IM) and palmitoyl-oleoyl-phosphatidylcholine (POPC), was administered to cynomolgus monkeys at 30, 100, and 300 mg/kg every other day for a total of 21 infusions, and effects on lipids, (apo)lipoproteins, and ex-vivo cholesterol efflux capacity were monitored. After 7 or 20 infusions, free cholesterol (FC) and phospholipids (PL) were strongly increased, and HDL-cholesterol (HDL-C), apoA-I, and apoA-II were strongly decreased. We then measured short-term effects on apoA-IM, lipids, and (apo)lipoproteins after the first or the last infusion. After the first infusion, PL and FC went up in the HDL region and also in the LDL and VLDL regions. ApoE shifted from HDL to LDL and VLDL regions, while ApoA-IM remained located in the HDL region. On day 41, ApoE levels were 8-fold higher than on day 1, and FC, PL, and apoE resided mostly in LDL and VLDL regions. Drug infusion quickly decreased the endogenous cholesterol esterification rate. ABCA1-mediated cholesterol efflux on day 41 was markedly increased, whereas scavenger receptor type B1 (SRB1) and ABCG1-mediated effluxes were only weakly increased. Strong increase of FC is due to sustained stimulation of ABCA1-mediated efflux, and drop in HDL and formation of large apoE-rich particles are due to lack of LCAT activation.
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Gomaraschi M, Ossoli A, Vitali C, Calabresi L. HDL and endothelial protection: examining evidence from HDL inherited disorders. ACTA ACUST UNITED AC 2013. [DOI: 10.2217/clp.13.30] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rui M, Guo W, Ding Q, Wei X, Xu J, Xu Y. Recombinant high-density lipoprotein nanoparticles containing gadolinium-labeled cholesterol for morphologic and functional magnetic resonance imaging of the liver. Int J Nanomedicine 2012; 7:3751-68. [PMID: 22888232 PMCID: PMC3414207 DOI: 10.2147/ijn.s33139] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Background Natural high-density lipoproteins (HDL) possess important physiological functions to the transport of cholesterol from the peripheral tissues to the liver for metabolic degradation and excretion in the bile. Methods and results In this work, we took advantage of this pathway and prepared two different gadolinium (Gd)-DTPA-labeled cholesterol-containing recombinant HDL nanoparticles (Gd-chol-HDL) and Gd-(chol)2-HDL as liver-specific magnetic resonance imaging (MRI) contrast agents. The reconstituted HDL nanoparticles had structural similarity to native HDL, and could be taken up by HepG2 cells via interaction with HDL receptors in vitro. In vivo MRI studies in rats after intravenous injections of 10 μmol gadolinium per kg of recombinant HDL nanoparticles indicated that both nanoparticles could provide signal enhancement in the liver and related organs. However, different T1-weighted image details suggested that they participated in different cholesterol metabolism and excretion pathways in the liver. Conclusion Such information could be highly useful to differentiate functional changes as well as anatomic differences in the liver. These cholesterol-derived contrast agents and their recombinant HDL preparations may warrant further development as a new class of contrast agents for MRI of the liver and related organs.
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Affiliation(s)
- Mengjie Rui
- School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
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20
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Farkas-Epperson M, Le NA. Lipoproteins as biosensors of endothelial oxidative status. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/clp.11.72] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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21
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Kavo AE, Rallidis LS, Sakellaropoulos GC, Lehr S, Hartwig S, Eckel J, Bozatzi PI, Anastasiou-Nana M, Tsikrika P, Kypreos KE. Qualitative characteristics of HDL in young patients of an acute myocardial infarction. Atherosclerosis 2011; 220:257-64. [PMID: 22056215 DOI: 10.1016/j.atherosclerosis.2011.10.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/17/2011] [Accepted: 10/13/2011] [Indexed: 11/27/2022]
Abstract
AIM Recently, the concept that high density lipoprotein (HDL) quality is an important parameter for atheroprotection is gaining ground, though little data exists so far to support it. In an attempt to identify measurable qualitative parameters of HDL associated with increased risk for premature myocardial infarction (MI), we studied the structural characteristics of HDL from patients who survived an MI at a young age (≤35 years). METHODS AND RESULTS We studied 20 MI patients and 20 healthy control subjects. HDL of patients had reduced apolipoprotein A-I (apoA-I), apolipoprotein M, and paraoxonase 1 levels and significantly elevated apolipoprotein C-III (apoCIII) levels (all p<0.05). Specifically, the HDL apoA-I/apoC-III ratio was 0.24±0.01 in patients versus 4.88±0.90 in controls (p<0.001). These structural alterations correlated with increased oxidation potential of HDL of the MI group compared to controls (2.5-fold, p=0.026). Electron microscopy showed no significant difference in average HDL particle diameter between the two groups though a significant difference existed in HDL diameter distribution, suggesting the presence of different HDL subpopulations in MI and control subjects. Indeed, non-denaturing two-dimensional electrophoresis revealed that MI patients had reduced pre-β1(α), pre-β1(b) and α(2), and elevated α(1), α(3), and pre-α(4) HDL. CONCLUSIONS Reduction in the HDL apoA-I/apoC-III ratio, changes in the HDL subpopulation distribution and an increase in HDL oxidation potential correlated with the development of MI in young patients. The possibility that such changes may serve as markers for the early identification of young individuals at high risk for an acute coronary event should be further explored.
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Affiliation(s)
- Anthula E Kavo
- Pharmacology Unit, Department of Medicine, University of Patras School of Health Sciences, Patras, Greece
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Curti MLR, Jacob P, Borges MC, Rogero MM, Ferreira SRG. Studies of gene variants related to inflammation, oxidative stress, dyslipidemia, and obesity: implications for a nutrigenetic approach. J Obes 2011; 2011:497401. [PMID: 21773006 PMCID: PMC3136190 DOI: 10.1155/2011/497401] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 02/15/2011] [Accepted: 03/14/2011] [Indexed: 01/05/2023] Open
Abstract
Obesity is currently considered a serious public health issue due to its strong impact on health, economy, and quality of life. It is considered a chronic low-grade inflammation state and is directly involved in the genesis of metabolic disturbances, such as insulin resistance and dyslipidemia, which are well-known risk factors for cardiovascular disease. Furthermore, there is evidence that genetic variation that predisposes to inflammation and metabolic disturbances could interact with environmental factors, such as diet, modulating individual susceptibility to developing these conditions. This paper aims to review the possible interactions between diet and single-nucleotide polymorphisms (SNPs) in genes implicated on the inflammatory response, lipoprotein metabolism, and oxidative status. Therefore, the impact of genetic variants of the peroxisome proliferator-activated receptor-(PPAR-)gamma, tumor necrosis factor-(TNF-)alpha, interleukin (IL)-1, IL-6, apolipoprotein (Apo) A1, Apo A2, Apo A5, Apo E, glutathione peroxidases 1, 2, and 4, and selenoprotein P exposed to variations on diet composition is described.
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Affiliation(s)
| | | | | | | | - Sandra Roberta G. Ferreira
- Department of Nutrition, School of Public Health, University of São Paulo, Avenida Dr. Arnaldo, 715, 01246-904, São Paulo, SP, Brazil
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Ahmed TAN, Karalis I, Jukema JW. Emerging drugs for coronary artery disease. From past achievements and current needs to clinical promises. Expert Opin Emerg Drugs 2011; 16:203-33. [DOI: 10.1517/14728214.2011.549606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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HDL biogenesis and functions: role of HDL quality and quantity in atherosclerosis. Atherosclerosis 2009; 208:3-9. [PMID: 19595353 DOI: 10.1016/j.atherosclerosis.2009.05.034] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 05/01/2009] [Accepted: 05/24/2009] [Indexed: 12/16/2022]
Abstract
Coronary heart disease (CHD) is a leading cause of death in western societies. In the last few decades, a number of epidemiological studies have shown that a disproportion between atheroprotective and atherogenic lipoproteins in plasma is one of the most important contributors towards atherosclerosis and CHD. Thus, based on the classical view, reduced HDL cholesterol levels independently predict one's risk factor for developing cardiovascular disease, while elevated HDL levels protect from atherosclerosis. However, more recent studies have suggested that the relationship between HDL and cardiovascular risk is more complex and extends beyond the levels of HDL in plasma. These studies challenge the existing view on HDL and cardiovascular risk and trigger a discussion as to whether low HDL is a causal effect for the development of heart disease. In this article we provide a review of the current literature on the biogenesis of HDL and its proposed functions in atheroprotection. In addition, we discuss the significance of both HDL quality and quantity in assessing cardiovascular risk.
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Alexander ET, Tanaka M, Kono M, Saito H, Rader DJ, Phillips MC. Structural and functional consequences of the Milano mutation (R173C) in human apolipoprotein A-I. J Lipid Res 2009; 50:1409-19. [PMID: 19318685 DOI: 10.1194/jlr.m800578-jlr200] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Carriers of the apolipoprotein A-I(Milano) (apoA-I(M)) variant, R173C, have reduced levels of plasma HDL but no increase in cardiovascular disease. Despite intensive study, it is not clear whether the removal of the arginine or the introduction of the cysteine is responsible for this altered functionality. We investigated this question using two engineered variations of the apoA-I(M) mutation: R173S apoA-I, similar to apoA-I(M) but incapable of forming a disulfide bond, and R173K apoA-I, a conservative mutation. Characterization of the lipid-free proteins showed that the order of stability was wild type approximately R173K>R173S>R173C. Compared with wild-type apoA-I, apoA-I(M) had a lower affinity for lipids, while R173S apoA-I displayed intermediate affinity. The in vivo effects of the apoA-I variants were measured by injecting apoA-I-expressing adeno-associated virus into apoA-I-null mice. Mice that expressed the R173S variant again showed an intermediate phenotype. Thus, both the loss of the arginine and its replacement by a cysteine contribute to the altered properties of apoA-I(M). The arginine is potentially involved in an intrahelical salt bridge with E169 that is disrupted by the loss of the positively charged arginine and repelled by the cysteine, destabilizing the helix bundle domain in the apoA-I molecule and modifying its lipid binding characteristics.
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Affiliation(s)
- Eric T Alexander
- Gastroenterology/Nutrition/Hepatology Division, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4318, USA
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Feng Y, Van Craeyveld E, Jacobs F, Lievens J, Snoeys J, De Geest B. Wild-type apo A-I and apo A-I(Milano) gene transfer reduce native and transplant arteriosclerosis to a similar extent. J Mol Med (Berl) 2008; 87:287-97. [PMID: 19066833 DOI: 10.1007/s00109-008-0427-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 10/29/2008] [Accepted: 11/27/2008] [Indexed: 10/21/2022]
Abstract
Apolipoprotein (apo) A-I(Milano) is an apo A-I mutant characterized by a cysteine for arginine substitution at position 173. Apo A-I(Milano) carriers have much less atherosclerosis than expected from their low plasma high-density lipoprotein cholesterol levels, suggesting that this mutant may have superior atheroprotective properties. Here, we compare the effect of hepatocyte-directed gene transfer of wild-type human apo A-I and human apo A-I(Milano) on endothelial progenitor cell (EPC) biology and on the progression of native atherosclerosis and allograft vasculopathy in C57BL/6 apo E(-/-) mice. Human apo A-I and apo A-I(Milano) transfer resulted in an equivalent increase of EPC number and function as well as EPC incorporation and endothelial regeneration in allografts and inhibited the progression of native atherosclerosis and allograft vasculopathy to a similar extent. In conclusion, the current head-to-head comparison indicates that human apo A-I(Milano) transfer is not superior compared to wild-type human apo A-I transfer.
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Affiliation(s)
- Yingmei Feng
- Center for Molecular and Vascular Biology, Campus Gasthuisberg, University of Leuven, Herestraat, Belgium
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Can We Cause Regression of Coronary Atherosclerosis? Am J Med Sci 2008; 335:368-74. [DOI: 10.1097/maj.0b013e31815c3b32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Trimerization of Apolipoprotein A-I Retards Plasma Clearance and Preserves Antiatherosclerotic Properties. J Cardiovasc Pharmacol 2008; 51:170-7. [DOI: 10.1097/fjc.0b013e31815ed0b9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sviridov D, Mukhamedova N, T. Remaley A, Chin-Dusting J, Nestel P. Antiatherogenic Functionality of High Density Lipoprotein: How Much versus How Gooden-subtitle=. J Atheroscler Thromb 2008; 15:52-62. [DOI: 10.5551/jat.e571] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Bove M, Cicero AFG, Manca M, Georgoulis I, Motta R, Incorvaia L, Giovannini M, Poggiopollini G, V Gaddi A. Sources of variability of plasma HDL-cholesterol levels. ACTA ACUST UNITED AC 2007. [DOI: 10.2217/17460875.2.5.557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Abstract
PURPOSE OF REVIEW This review focuses on recent progress towards the characterization of genetic variations that contribute to interindividual variation in plasma high-density lipoprotein cholesterol levels in the general population. RECENT FINDINGS Many of the genes that harbor rare mutations leading to extreme high-density lipoprotein cholesterol levels contain common variation that influences plasma high-density lipoprotein cholesterol in several study populations. Candidate gene association studies provide evidence that some of these variations have an effect on high-density lipoprotein cholesterol, dependent on epistatic interactions or environmental context. Both rare and common variations contribute to interindividual high-density lipoprotein cholesterol variation. Recent comparisons of candidate gene sequences between individuals in the tails of the high-density lipoprotein cholesterol distributions (the upper or lower 1-5%) of several study populations indicate that as many as 20% of individuals with low high-density lipoprotein cholesterol harbor a rare mutation in an investigated gene. For example, the ABCA1 gene region harbors rare mutations and common variants that contribute to interindividual high-density lipoprotein cholesterol variation in the general population. SUMMARY The genetic control of high-density lipoprotein cholesterol level is complex. Maximizing the utility of genetic knowledge for predicting an individual's high-density lipoprotein cholesterol level or response to intervention will require a better understanding of the action of combinations of genetic variants and environmental exposures.
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Affiliation(s)
- Kathy L E Klos
- aHuman Genetics Center, University of Texas Health Science Center, Houston, Texas 77225, USA.
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Favari E, Gomaraschi M, Zanotti I, Bernini F, Lee-Rueckert M, Kovanen PT, Sirtori CR, Franceschini G, Calabresi L. A Unique Protease-sensitive High Density Lipoprotein Particle Containing the Apolipoprotein A-IMilano Dimer Effectively Promotes ATP-binding Cassette A1-mediated Cell Cholesterol Efflux. J Biol Chem 2007; 282:5125-32. [PMID: 17164237 DOI: 10.1074/jbc.m609336200] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Carriers of the apolipoprotein A-I(Milano) (A-I(M)) variant present with severe reductions of plasma HDL levels, not associated with premature coronary heart disease (CHD). Sera from 14 A-I(M) carriers and matched controls were compared for their ability to promote ABCA1-driven cholesterol efflux from J774 macrophages and human fibroblasts. When both cell types are stimulated to express ABCA1, the efflux of cholesterol through this pathway is greater with A-I(M) than control sera (3.4 +/- 1.0% versus 2.3 +/- 1.0% in macrophages; 5.2 +/- 2.4% versus 1.9 +/- 0.1% in fibroblasts). A-I(M) and control sera are instead equally effective in removing cholesterol from unstimulated cells and from fibroblasts not expressing ABCA1. The A-I(M) sera contain normal amounts of apoA-I-containing prebeta-HDL and varying concentrations of a unique small HDL particle containing a single molecule of the A-I(M) dimer; chymase treatment of serum degrades both particles and abolishes ABCA1-mediated cholesterol efflux. The serum content of chymase-sensitive HDL correlates strongly and significantly with ABCA1-mediated cholesterol efflux (r = 0.542, p = 0.004). The enhanced capacity of A-I(M) serum for ABCA1 cholesterol efflux is thus explained by the combined occurrence in serum of normal amounts of apoA-I-containing prebeta-HDL, together with a unique protease-sensitive, small HDL particle containing the A-I(M) dimer, both effective in removing cell cholesterol via ABCA1.
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Affiliation(s)
- Elda Favari
- Department of Pharmacological and Biological Sciences, and Applied Chemistries, University of Parma, Viale delle Scienze 27A, 43100 Parma, Italy
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Rocco AG, Mollica L, Gianazza E, Calabresi L, Franceschini G, Sirtori CR, Eberini I. A model structure for the heterodimer apoA-IMilano-apoA-II supports its peculiar susceptibility to proteolysis. Biophys J 2006; 91:3043-9. [PMID: 16891368 PMCID: PMC1578475 DOI: 10.1529/biophysj.106.085886] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In this study, we propose a structure for the heterodimer between apolipoprotein A-I(Milano) and apolipoprotein A-II (apoA-I(M)-apoA-II) in a synthetic high-density lipoprotein (HDL) containing L-alpha-palmitoyloleoyl phosphatidylcholine. We applied bioinformatics/computational tools and procedures, such as molecular docking, molecular and essential dynamics, starting from published crystal structures for apolipoprotein A-I and apolipoprotein A-II. Structural and energetic analyses onto the simulated system showed that the molecular dynamics produced a stabilized synthetic HDL. The essential dynamic analysis showed a deviation from the starting belt structure. Our structural results were validated by limited proteolysis experiments on HDL from apoA-I(M) carriers in comparison with control HDL. The high sensitivity of apoA-I(M)-apoA-II to proteases was in agreement with the high root mean-square fluctuation values and the reduction in secondary structure content from molecular dynamics data. Circular dichroism on synthetic HDL containing apoA-I(M)-apoA-II was consistent with the alpha-helix content computed on the proposed model.
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Affiliation(s)
- Alessandro Guerini Rocco
- Gruppo di Studio per la Proteomica e la Struttura delle Proteine, Centro E. Grossi Paoletti, Dipartimento di Scienze Farmacologiche, Università degli Studi di Milano, Milan, Italy
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Brewer HB. Hollis Bryan Brewer, Jr., MD: a conversation with the editor. Am J Cardiol 2006; 97:1791-804. [PMID: 16765137 DOI: 10.1016/j.amjcard.2006.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Accepted: 03/22/2006] [Indexed: 10/24/2022]
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Rashid S, Patterson BW, Lewis GF. Thematic review series: patient-oriented research. What have we learned about HDL metabolism from kinetics studies in humans? J Lipid Res 2006; 47:1631-42. [PMID: 16685079 DOI: 10.1194/jlr.r600008-jlr200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Plasma measurements of lipids, lipoproteins, and apolipoproteins provide information on the static levels of these fractions without providing key information on the dynamic fluxes of lipoproteins in the circulation. Kinetics studies, in contrast, provide additional information on the production and clearance rates of lipoproteins and the flow of lipids and apolipoproteins through lipoprotein fractions. This information is crucial in accurately delineating the metabolism of HDL in plasma, because plasma concentrations of HDL are the net result of the de novo production and catabolism of HDL as well as the recycling of HDL particles and the contribution to HDL from components of other lipoproteins. Studies aimed at measuring the metabolism of HDL particles have shown that HDL metabolism in vivo is complex and consists of multiple components. Kinetics studies provide a window into the metabolism of HDL, allowing us to better understand the mechanisms of HDL decrease in human conditions and the functionality of HDL particles. Here, we review the progress in our understanding of HDL metabolism derived from in vivo kinetics studies, focusing primarily on studies in humans but also reviewing key studies in animal models.
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Affiliation(s)
- Shirya Rashid
- Department of Cardiology, McGill University, Montreal, Canada
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Abstract
Longitudinal population studies have confirmed plasma levels of high-density lipoprotein (HDL) cholesterol to be an important inverse coronary risk factor. Although environmental influences are known to regulate HDL cholesterol levels, genetic factors are also known to be important, and over 25 candidate genes have been proposed to be associated with variation in HDL cholesterol levels. A variety of monogenic conditions of extremely low or high HDL cholesterol has helped to delineate the physiology of HDL cholesterol metabolism in humans, which has led to the development of new therapeutic approaches to HDL cholesterol. However, most causes of genetic variation in HDL cholesterol in the general population are likely oligogenic or polygenic. We review the monogenic disorders associated with both high and low HDL cholesterol and the relevance of mutations and polymorphisms in these genes to variation in HDL cholesterol levels in the general population.
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Affiliation(s)
- Atif Qasim
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania School of Medicine, 421 Curie Boulevard, Philadelphia, PA 19104, USA
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Marchesi M, Sirtori CR. Therapeutic use of the high-density lipoprotein protein and peptides. Expert Opin Investig Drugs 2006; 15:227-41. [PMID: 16503760 DOI: 10.1517/13543784.15.3.227] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
High-density lipoprotein (HDL) therapy is a novel and emerging area of therapeutic development in the cardiovascular field. It attempts to supplement and improve the vascular benefit exerted by other agents that are active on lipid metabolism, for example, hypolipidaemic drugs. Furthermore, it takes advantage of the novel techniques of coronary evaluation. A number of reports have examined the potential therapeutic properties of the synthetic HDLs prepared by complexing recombinant apolipoprotein (apo) A-I(Milano), a variant form of native apoA-I, with phospholipids. The availability of synthetic HDL complexes containing recombinant apoA-I(Milano) has opened up a new era of therapeutic management for coronary disease. HDL formulations of recombinant apoA-I(Milano)-phospholipid complexes have clearly shown rapid regression of a focal carotid atheroma as well as powerful protection from myocardial infarction in a rabbit model. In a pilot study, ETC-216 showed a significant reduction in coronary plaque burden after five weekly treatments, assessed by intravascular ultrasound in patients with acute coronary syndrome. Other therapeutic options of HDL therapy have recently became available.
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Affiliation(s)
- Marta Marchesi
- Department of Pharmacological Sciences, University of Milan, 20133 Milan, Italy.
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Sirtori CR. Properties of ApoA-I Milano. Nat Rev Drug Discov 2005. [DOI: 10.1038/nrd1554-c1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Marchesi M, Booth EA, Davis T, Bisgaier CL, Lucchesi BR. Apolipoprotein A-IMilanoand 1-Palmitoyl-2-oleoyl Phosphatidylcholine Complex (ETC-216) Protects the in Vivo Rabbit Heart from Regional Ischemia-Reperfusion Injury. J Pharmacol Exp Ther 2004; 311:1023-31. [PMID: 15375174 DOI: 10.1124/jpet.104.070789] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ex vivo studies demonstrated that a synthetic high-density lipoprotein (HDL) comprised of a complex of recombinant apolipoprotein A-IMilano and 1-palmitoyl-2-oleoyl phosphatidylcholine protects the isolated rabbit heart from reperfusion injury. Therefore, we sought to determine whether a pharmaceutical preparation of this complex, ETC-216, was cardioprotective in an in vivo model of left anterior descending artery (LAD) occlusion and reperfusion. Initially, ETC-216 (100 mg/kg) was tested in acute (one-treatment) and chronic (two-treatment) i.v. administrations. ETC-216-treated rabbits developed smaller infarcts expressed as percentage of area at risk (p <0.01) compared with vehicle treatments. No differences were noted between chronic and acute administration. Therefore, ETC-216 (10, 3, or 1 mg/kg) or equivalent vehicle volumes were acutely infused. Compared with vehicle, ETC-216 reduced infarct size as a percentage of the area at risk at 10 (p <0.0005) and 3 mg/kg (p <0.05). No significant differences occurred at 1 mg/kg. To determine whether ETC-216 could protect the heart after initiation of ischemia, the synthetic HDL (10 mg/kg) was infused intravenously beginning 5 min before the end of 30 min of LAD occlusion. Infarct size as percentage of the area at risk was 31.6 +/- 3.0 (ETC-216) versus 49.5 +/- 2.5 (vehicle) (p <0.001), and as percentage of left ventricle was 19.7 +/- 1.6 (ETC-216) versus 34.1 +/- 2.3 (vehicle) (p <0.0005). Electron microscopy demonstrated that ETC-216 prevented irreversible cardiac damage as assessed by mitochondrial granulation and sarcomere contraction band formation. These findings suggest ETC-216 reduces reperfusion injury and may have utility for coronary artery revascularization procedures.
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Affiliation(s)
- Marta Marchesi
- Department of Pharmacology, University of Michigan Medical School, 1301C Medical Science Research Bldg. III, Ann Arbor, MI 48109-0632, USA
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Moyad MA. Introduction to risk assessment and serum risk markers for the prevention of coronary heart disease and other potential conditions that impact men's health, part II: what do I tell my patients? Urol Clin North Am 2004; 31:199-205. [PMID: 15123399 DOI: 10.1016/j.ucl.2004.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Markers and other potential tests for cardiovascular risk abound, and a more extensive review of these and other markers can be found elsewhere. Cardiovascular health tends to mirror urologic health for several conditions. It is imperative in the urology setting that clinicians discuss the probability of early morbidity and mortality with patients. This should not undermine the importance of prostate cancer and other diseases, but rather place risks in their proper perspective. Patients seem to need this guidance more than ever because life expectancy for most individuals continues to increase, and the potential for comorbidities seems to increase in the average aging patient. It is hoped that this article will prompt new interest in evaluating some risk factors for various urologic conditions. This may move researchers closer to discovering intervention agents that could impact numerous male health conditions favorably. Improving men's health will require a concerted educational and research effort from several health disciplines, a reminder that different medical specialties have much in common, and the role of preventive medicine is to point out similarities as opposed to differences.
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Affiliation(s)
- Mark A Moyad
- Department of Urology, University of Michigan Medical Center, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0330, USA.
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Sirtori CR. New frontiers in atherosclerosis prevention and treatment: HDL as a novel therapeutic target. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.ics.2003.12.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
PURPOSE OF REVIEW Strategies to increase HDL are among the major targets of clinical research in atherosclerosis prevention. The mutant apolipoprotein A-I(Milano) has been associated with a reduced incidence of coronary disease in carriers. Furthermore, recombinant apolipoprotein A-I(Milano) has displayed remarkable atheroprotective activities and the possibility of directly reducing the burden of atherosclerosis in experimental models. This review is aimed at providing an update on the experimental studies in which apolipoprotein A-I(Milano), produced as a recombinant protein, has displayed important effects in the treatment of vascular diseases. RECENT FINDINGS In the past year, two reports have appeared, indicating that a single-dose administration of recombinant apolipoprotein A-I(Milano) dimers formulated into liposomes can reduce atheromas in models such as the apolipoprotein E-deficient mice and a rabbit model of carotid focal lesion, in which a direct 90 min infusion of the product reduced atheroma up to 30%. This finding was associated with an increase in HDL free cholesterol and the permanence of the recombinant product in the lesion for over 72 h. SUMMARY Recombinant apolipoprotein A-I(Milano), formulated as synthetic HDL with phospholipids, appears to exert a direct removing effect on arterial cholesterol. This is well evident in experimental animals and, more recently in clinical findings, as indicated by a dramatic increase in HDL free cholesterol after the infusion of different doses of the agent. As the product appears to be well tolerated and non-immunogenic, ongoing phase II studies in patients are being awaited with interest to obtain a 'proof of principle' for 'HDL therapy'.
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Affiliation(s)
- Giulia Chiesa
- Department of Pharmacological Sciences, University of Milano, via Balzaretti 9, 20133, Milano, Italy.
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45
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Parolini C, Chiesa G, Zhu Y, Forte T, Caligari S, Gianazza E, Sacco MG, Sirtori CR, Rubin EM. Targeted replacement of mouse apolipoprotein A-I with human ApoA-I or the mutant ApoA-IMilano. Evidence of APOA-IM impaired hepatic secretion. J Biol Chem 2003; 278:4740-6. [PMID: 12471038 DOI: 10.1074/jbc.m207335200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Despite a pro-atherogenic profile, individuals carrying the molecular variant (R173C) of apolipoprotein (apo)A-I, named apoA-I(Milano) (apoA-I(M)), appear to be at reduced risk for cardiovascular disease. To develop an in vivo system to explore, in a controlled manner, the effects of apoA-I(M) on lipid metabolism, we have used the gene targeting technology, or "gene knock-in" (gene k-in), to replace the murine apoA-I gene with either human apoA-I or apoA-I(M) genes in embryonic stem cells. As in human carriers, mice expressing apoA-I(M) (A-I(M) k-in) are characterized by low concentrations of the human apolipoprotein and reduced high density lipoprotein cholesterol levels, compared with A-I k-in animals. The aim of the present study was to investigate the basic mechanisms of hypoalphalipoproteinemia associated with the apoA-I(M) mutation. ApoA-I and apoA-I(M) mRNA expression, as assessed by Northern blot analysis and quantitative real time reverse transcription-PCR, did not exhibit significant differences in either liver or intestine. Moreover, human apolipoprotein synthesis rates were similar in the k-in lines. When the secretion rate of the human apolipoproteins was assessed in cultured hepatocytes from the mouse lines, secretion from apoA-I(M)-expressing cells was markedly reduced (42% for A-I(M) k-in and 36% for A-I/A-I(M) k-in mice) as compared with that of A-I k-in hepatocytes. These results provide the first evidence that the hypoalphalipoproteinemia in apoA-I(M) human carriers may be partially explained by impaired apoA-I(M) secretion.
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Affiliation(s)
- Cinzia Parolini
- Department of Pharmacological Sciences, University of Milan, 20133 Milan, Italy.
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Chiesa G, Sirtori CR. Recombinant apolipoprotein A-I(Milano): a novel agent for the induction of regression of atherosclerotic plaques. Ann Med 2003; 35:267-73. [PMID: 12846269 DOI: 10.1080/07853890310005281] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Apolipoprotein (apo) A-I, because of its anti-atherogenic properties, provides a potentially powerful approach to the management of vascular diseases. In the clinic, patients with low high density lipoproteins (HDL)/apoA-I are at dramatically increased risk of coronary disease, the opposite being true for individuals with high HDL Drug studies, e.g., the VA-HIT trial with gemfibrozil, clearly associated a reduced risk of events with raised HDL-cholesterolemia. A number of animal studies have shown that the infusion of apoA-I containing synthetic HDL can inhibit atherosclerosis progression in experimental animals, being also able to stimulate reverse cholesterol transport in humans. Recently, high interest has been devoted to a molecular variant of apoA-I, apoA-I(Milano) (apoA-I(M)), characterized by a Cys for Arg substitution and formation of apoA-I(M)/A-I(M) dimers. These latter are characterized by a prolonged permanence in plasma and a more effective cholesterol removing function, which may offer an improved approach to the therapeutic management of arterial disease. Aside from a number of clinical studies on human apoA-I(M) carriers, all indicating a clear protection from cardiovascular disease in spite of markedly reduced HDL levels, animal investigations have provided definite indication as to the potential of apoA-I(M) infusion to directly reduce the extent of atherosclerotic plaques. In addition to the well known powerful cholesterol effluxing capacity of apoA-I(M), fibrinolytic properties and possibly antioxidant/vasodilator mechanisms seem to be in play. Ongoing clinical studies will provide final indication as to the potential of this new therapeutic approach.
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Affiliation(s)
- Giulia Chiesa
- Department of Pharmacological Sciences, University of Milano, Italy
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47
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Jia Z, Natarajan P, Forte TM, Bielicki JK. Thiol-bearing synthetic peptides retain the antioxidant activity of apolipoproteinA-I(Milano). Biochem Biophys Res Commun 2002; 297:206-13. [PMID: 12237103 DOI: 10.1016/s0006-291x(02)02143-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Apolipoprotein(apo)A-I(Milano) (R173C) and apoA-I(Paris) (R151C) are rare cysteine variants of wild-type (WT) apoA-I that possess novel antioxidant properties on phospholipid surfaces. Yet, the two variants differ in their ability to inhibit lipid peroxidation. In this study, we used synthetic peptides (18mers) to investigate the structural basis for the difference in antioxidant activity between apoA-I(Milano) and apoA-I(Paris). A peptide (aa 167-R173C-184) based on the amphipathic alpha helix harboring the R173C mutation inhibited superoxide anion-mediated oxidation of phospholipid in a dose-dependent manner, but it failed to directly quench superoxide anions in aqueous solution, indicating that the peptide acted at the level of phospholipid to inhibit lipid peroxidation just like the full-length cysteine variant. Peptide 145-R151C-162 based on the helical segment containing R151C exhibited the same capacity as peptide 167-R173C-184 to inhibit lipid peroxidation. Thus, the difference in antioxidant activity between apoA-I(Milano) and apoA-I(Paris) was not governed by the primary amino acid sequence of their individual amphipathic alpha helices, rather contextual constraints within the full-length variants set the difference in antioxidant activity. Cysteine-free peptides were weak inhibitors of lipid peroxidation. These results suggest that thiol-bearing helical peptides based on apoA-I(Milano) may be useful to combat inflammatory related diseases.
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Affiliation(s)
- Zhen Jia
- Department of Genome Sciences, Division of Life Sciences, Lawrence Berkeley National Laboratory, CA 94720, USA
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Chiesa G, Monteggia E, Marchesi M, Lorenzon P, Laucello M, Lorusso V, Di Mario C, Karvouni E, Newton RS, Bisgaier CL, Franceschini G, Sirtori CR. Recombinant apolipoprotein A-I(Milano) infusion into rabbit carotid artery rapidly removes lipid from fatty streaks. Circ Res 2002; 90:974-80. [PMID: 12016263 DOI: 10.1161/01.res.0000018422.31717.ee] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Apolipoprotein A-I(Milano) (AIM), a natural variant of human apolipoprotein A-I, confers to carriers a significant protection against vascular disease. In previous studies, administration of recombinant AIM-phospholipid (AIM-PL) complexes to hypercholesterolemic rabbits markedly inhibited neointimal formation after arterial injury; moreover, repeated injections of AIM-PL in apoE-deficient mice significantly reduced atherosclerosis progression. The objective of the present study was to determine if a single localized infusion of AIM-PL complexes administered directly to atheromatous lesions could promote plaque regression. Lipid-rich, atheromatous plaques were generated at both common carotid arteries of 25 rabbits by applying a perivascular electric injury, followed by 1.5% cholesterol diet for 90 days. Rabbits were infused with either saline, phospholipid vesicles, or 3 different AIM-PL doses (250, 500, or 1000 mg of protein) delivered through an intravascular ultrasound (IVUS) catheter positioned at the origin of the right carotid. The lesions at the left carotid artery were therefore exposed to the agents systemically. Infusion of AIM-PL at the 2 highest doses caused reduction of right carotid artery plaque area by the end a 90-minute infusion as assessed by IVUS analysis. Plaque area regression was confirmed by histology in carotid arteries receiving direct (500 and 1000 mg doses) and systemic (500 mg dose) delivery, 72 hours after the start of the treatment. Plaque lipid content was associated with significant and similar decreases in Oil Red O staining in both arteries. These results suggest AIM-PL complexes enhanced lipid removal from arteries is the mechanism responsible for the observed plaque changes.
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Affiliation(s)
- Giulia Chiesa
- Department of Pharmacological Sciences, University of Milano, Italy.
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Bielicki JK, Oda MN. Apolipoprotein A-I(Milano) and apolipoprotein A-I(Paris) exhibit an antioxidant activity distinct from that of wild-type apolipoprotein A-I. Biochemistry 2002; 41:2089-96. [PMID: 11827556 DOI: 10.1021/bi011716p] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Apolipoprotein A-I(Milano) (apoA-I(Milano)) and apoA-I(Paris) are rare cysteine variants of apoA-I that produce a HDL deficiency in the absence of cardiovascular disease in humans. This paradox provides the basis for the hypothesis that the cysteine variants possess a beneficial activity not associated with wild-type apoA-I (apoA-I(WT)). In this study, a unique antioxidant activity of apoA-I(Milano) and apoA-I(Paris) is described. ApoA-I(Milano) was twice as effective as apoA-I(Paris) in preventing lipoxygenase-mediated oxidation of phospholipids, whereas apoA-I(WT) was poorly active. Antioxidant activity was observed using the monomeric form of the variants and was equally effective before and after initiation of oxidative events. ApoA-I(Milano) protected phospholipid from reactive oxygen species (ROS) generated via xanthine/xanthine oxidase (X/Xo) but failed to inhibit X/Xo-induced reduction of cytochrome c. These results indicate that apoA-I(Milano) was unable to directly quench ROS in the aqueous phase. There were no differences between lipid-free apoA-I(Milano,) apoA-I(Paris), and apoA-I(WT) in mediating the efflux of cholesterol from macrophages, indicating that the cysteine variants interacted normally with the ABCA1 efflux pathway. The results indicate that incorporation of a free thiol within an amphipathic alpha helix of apoA-I confers an antioxidant activity distinct from that of apoA-I(WT). These studies are the first to relate gain of function to rare cysteine mutations in the apoA-I primary sequence.
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Affiliation(s)
- John K Bielicki
- Genome Sciences Department, Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
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ApoA-IMALLORCA impairs LCAT activation and induces dominant familial hypoalphalipoproteinemia. J Lipid Res 2002. [DOI: 10.1016/s0022-2275(20)30194-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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