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Akyol O, Yang CY, Woodside DG, Chiang HH, Chen CH, Gotto AM. Comparative Analysis of Atherogenic Lipoproteins L5 and Lp(a) in Atherosclerotic Cardiovascular Disease. Curr Atheroscler Rep 2024; 26:317-329. [PMID: 38753254 PMCID: PMC11192678 DOI: 10.1007/s11883-024-01209-3] [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] [Accepted: 05/05/2024] [Indexed: 06/22/2024]
Abstract
PURPOSE OF REVIEW Low-density lipoprotein (LDL) poses a risk for atherosclerotic cardiovascular disease (ASCVD). As LDL comprises various subtypes differing in charge, density, and size, understanding their specific impact on ASCVD is crucial. Two highly atherogenic LDL subtypes-electronegative LDL (L5) and Lp(a)-induce vascular cell apoptosis and atherosclerotic changes independent of plasma cholesterol levels, and their mechanisms warrant further investigation. Here, we have compared the roles of L5 and Lp(a) in the development of ASCVD. RECENT FINDINGS Lp(a) tends to accumulate in artery walls, promoting plaque formation and potentially triggering atherosclerosis progression through prothrombotic or antifibrinolytic effects. High Lp(a) levels correlate with calcific aortic stenosis and atherothrombosis risk. L5 can induce endothelial cell apoptosis and increase vascular permeability, inflammation, and atherogenesis, playing a key role in initiating atherosclerosis. Elevated L5 levels in certain high-risk populations may serve as a distinctive predictor of ASCVD. L5 and Lp(a) are both atherogenic lipoproteins contributing to ASCVD through distinct mechanisms. Lp(a) has garnered attention, but equal consideration should be given to L5.
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Affiliation(s)
- Omer Akyol
- Molecular Cardiology Research Laboratories, Vascular and Medicinal Research, The Texas Heart Institute, Houston, Texas, 77030, USA
| | - Chao-Yuh Yang
- Department of Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, Texas, 77030, USA
| | - Darren G Woodside
- Molecular Cardiology Research Laboratories, The Texas Heart Institute, Houston, TX, 77030, USA
| | - Huan-Hsing Chiang
- Molecular Cardiology Research Laboratories, Vascular and Medicinal Research, The Texas Heart Institute, Houston, Texas, 77030, USA
| | - Chu-Huang Chen
- Molecular Cardiology Research Laboratories, Vascular and Medicinal Research, The Texas Heart Institute, Houston, Texas, 77030, USA.
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Vazirian F, Sadeghi M, Kelesidis T, Budoff MJ, Zandi Z, Samadi S, Mohammadpour AH. Predictive value of lipoprotein(a) in coronary artery calcification among asymptomatic cardiovascular disease subjects: A systematic review and meta-analysis. Nutr Metab Cardiovasc Dis 2023; 33:2055-2066. [PMID: 37567791 PMCID: PMC11073574 DOI: 10.1016/j.numecd.2023.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 05/20/2023] [Accepted: 07/11/2023] [Indexed: 08/13/2023]
Abstract
AIMS Studies have indicated inconsistent results regarding the association between plasma levels of Lipoprotein(a) [Lp(a)] and coronary artery calcification (CAC). We performed a systematic review and meta-analysis to investigate the association between elevated levels of Lp(a) and risk of CAC in populations free of cardiovascular disease (CVD) symptoms. DATA SYNTHESIS PubMed, Web of Science, Embase, and Scopus were searched up to July 2022 and the methodological quality was assessed using Newcastle-Ottawa Scale (NOS) scale. Random-effects meta-analysis was used to estimate pooled odds ratio (OR) and 95% confidence interval. Out of 298 studies, data from 8 cross-sectional (n = 18,668) and 4 cohort (n = 15,355) studies were used in meta-analysis. Cohort studies demonstrated a positive significant association between Lp(a) and CAC, so that individuals with Lp(a)≥30-50 exposed to about 60% risk of CAC incidence compared to those with lower Lp(a) concentrations in asymptomatic CVD subjects (OR, 1.58; 95% CI, 1.38-1.80; l2, 0.0%; P, 0.483); Subgroup analysis showed that a cut-off level for Lp(a) measurement could not statistically affect the association, but race significantly affected the relationship between Lp(a) and CAC (OR,1.60; 95% CI, 1.41-1.81). Analyses also revealed that both men and women with higher Lp(a) concentrations are at the same risk for increased CAC. CONCLUSIONS Blood Lp(a) level was significantly associated with CAC incidence in asymptomatic populations with CVD, indicating that measuring Lp(a) may be a useful biomarker for diagnosing subclinical atherosclerosis in individuals at higher risk of CAC score. PROSPERO REGISTRATION NUMBER CRD42022350297.
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Affiliation(s)
- Fatemeh Vazirian
- School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Masoumeh Sadeghi
- Department of Epidemiology, Faculty of Health, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Theodoros Kelesidis
- Department of Medicine, Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Matthew J Budoff
- Department of Medicine, Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Zahra Zandi
- Department of Cardiovascular Disease, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sara Samadi
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Amir Hooshang Mohammadpour
- Department of Clinical Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran; Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
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Gianazza E, Zoanni B, Mallia A, Brioschi M, Colombo GI, Banfi C. Proteomic studies on apoB-containing lipoprotein in cardiovascular research: A comprehensive review. MASS SPECTROMETRY REVIEWS 2023; 42:1397-1423. [PMID: 34747518 DOI: 10.1002/mas.21747] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 08/05/2021] [Accepted: 08/16/2021] [Indexed: 06/07/2023]
Abstract
The complexity of cardiovascular diseases (CVDs), which remains the leading cause of death worldwide, makes the current clinical pathway for cardiovascular risk assessment unsatisfactory, as there remains a substantial unexplained residual risk. Simultaneous assessment of a large number of plasma proteins may be a promising tool to further refine risk assessment, and lipoprotein-associated proteins have the potential to fill this gap. Technical advances now allow for high-throughput proteomic analysis in a reproducible and cost-effective manner. Proteomics has great potential to identify and quantify hundreds of candidate marker proteins in a sample and allows the translation from isolated lipoproteins to whole plasma, thus providing an individual multiplexed proteomic fingerprint. This narrative review describes the pathophysiological roles of atherogenic apoB-containing lipoproteins and the recent advances in their mass spectrometry-based proteomic characterization and quantitation for better refinement of CVD risk assessment.
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Affiliation(s)
| | | | - Alice Mallia
- Centro Cardiologico Monzino, IRCCS, Milano, Italy
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Ward NC, Watts GF, Bishop W, Colquhoun D, Hamilton-Craig C, Hare DL, Kangaharan N, Kostner KM, Kritharides L, O'Brien R, Mori TA, Nestel PJ, Nicholls SJ, Psaltis PJ, Raffoul N, White HD, Sullivan DR. Australian Atherosclerosis Society Position Statement on Lipoprotein(a): Clinical and Implementation Recommendations. Heart Lung Circ 2023; 32:287-296. [PMID: 36707360 DOI: 10.1016/j.hlc.2022.11.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 11/09/2022] [Indexed: 01/26/2023]
Abstract
This position statement provides guidance to cardiologists and related specialists on the management of adult patients with elevated lipoprotein(a) [Lp(a)]. Elevated Lp(a) is an independent and causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve disease (CAVD). While circulating Lp(a) levels are largely determined by ancestry, they are also influenced by ethnicity, hormones, renal function, and acute inflammatory events, such that measurement should be done after accounting for these factors. Further, circulating Lp(a) concentrations should be estimated using an apo(a)-isoform independent assay that employs appropriate calibrators and reports the results in molar units (nmol/L). Selective screening strategies of high-risk patients are recommended, but universal screening of the population is currently not advised. Testing for elevated Lp(a) is recommended in all patients with premature ASCVD and those considered to be at intermediate-to-high risk of ASCVD. Elevated Lp(a) should be employed to assess and stratify risk and to enable a decision on initiation or intensification of preventative treatments, such as cholesterol lowering therapy. In adult patients with elevated Lp(a) at intermediate-to-high risk of ASCVD, absolute risk should be reduced by addressing all modifiable behavioural, lifestyle, psychosocial and clinical risk factors, including maximising cholesterol-lowering with statin and ezetimibe and, where appropriate, PCSK9 inhibitors. Apheresis should be considered in patients with progressive ASCVD. New ribonucleic acid (RNA)-based therapies which directly lower Lp(a) are undergoing clinical trials.
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Affiliation(s)
- Natalie C Ward
- Dobney Hypertension Centre, Medical School, University of Western Australia, Perth, WA, Australia.
| | - Gerald F Watts
- Medical School, University of Western Australia, Perth, WA, Australia; Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth, WA, Australia
| | | | - David Colquhoun
- Faculty of Medicine, Wesley Medical Centre, Brisbane, Qld, Australia; Faculty of Medicine, Medical School, University of Queensland, Brisbane, Qld, Australia
| | - Christian Hamilton-Craig
- Faculty of Medicine, University of Queensland, Brisbane, Qld, Australia; Faculty of Medicine, Dentistry and Health, School of Medicine, Griffith University, Sunshine Coast, Qld, Australia
| | - David L Hare
- Faculty of Medicine, Dentistry & Health Sciences, University of Melbourne, Melbourne, Vic, Australia and Department of Cardiology, Austin Hospital, Heidelberg, Vic, Australia
| | | | - Karam M Kostner
- Department of Cardiology, Mater Hospital, Brisbane, Qld, Australia; Medical School, University of Queensland, Brisbane, Qld, Australia
| | - Leonard Kritharides
- Sydney Medical School, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia and Department of Cardiology, Concord Repatriation General Hospital, Sydney Local Health District, Sydney, NSW, Australia
| | - Richard O'Brien
- Austin Clinical School, University of Melbourne, Melbourne, Vic, Australia and Director of Lipid Services, Austin Health, Melbourne, Vic, Australia
| | - Trevor A Mori
- Medical School, University of Western Australia, Perth, WA, Australia
| | - Paul J Nestel
- Baker Heart & Diabetes Institute, Melbourne, Vic, Australia
| | - Stephen J Nicholls
- Monash Cardiovascular Research Centre, Victorian Heart Institute, Monash University, Melbourne, Vic, Australia
| | - Peter J Psaltis
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia; Vascular Research Centre, Lifelong Health Theme, South Australian Health & Medical Research Institute, Adelaide, SA, Australia; and Department of Cardiology, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | | | - Harvey D White
- Te Whatu Ora-Health New Zealand, Green Lane Cardiovascular Service, Te Toka Tumai, Auckland, New Zealand
| | - David R Sullivan
- Medical School, University of Sydney, Sydney, NSW, Australia; Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia, and Department of Biochemistry, Royal Prince Alfred Hospital, Sydney, NSW, Australia
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Abstract
PURPOSE OF REVIEW To provide an overview of the associations between elevated blood pressure and lipoprotein (a) and possible causal links, as well as data on the prevalence of elevated lipoprotein (a) in a cohort of hypertensive patients. RECENT FINDINGS Elevated lipoprotein (a) is now considered to be an independent and causal risk factor for atherosclerotic cardiovascular disease and calcific aortic valve disease. Despite this, there are limited data demonstrating an association between elevated lipoprotein (a) and hypertension. Further, there is limited mechanistic data linking lipoprotein (a) and hypertension through either renal impairment or direct effects on the vasculature. Despite the links between lipoprotein (a) and atherosclerosis, there are limited data demonstrating an association with hypertension. Evidence from our clinic suggests that ~ 30% of the patients in this at-risk, hypertensive cohort had elevated lipoprotein (a) levels and that measurement of lipoprotein (a) maybe useful in risk stratification.
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Ong KL, McClelland RL, Allison MA, Cushman M, Garg PK, Tsai MY, Rye KA, Tabet F. Lipoprotein (a) and coronary artery calcification: prospective study assessing interactions with other risk factors. Metabolism 2021; 116:154706. [PMID: 33421505 PMCID: PMC7853621 DOI: 10.1016/j.metabol.2021.154706] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/24/2020] [Accepted: 01/05/2021] [Indexed: 12/16/2022]
Abstract
BACKGROUND Elevated plasma lipoprotein (a) [Lp(a)] and coronary artery calcification (CAC) are established cardiovascular risk factors that correlate with each other. We hypothesized that other cardiovascular risk factors could affect their relationship. METHODS We tested for interactions of 24 study variables related to dyslipidemia, diabetes, insulin resistance, hypertension, inflammation and coagulation with baseline Lp(a) on change in CAC volume and density over 9.5 years in 5975 Multi-Ethnic Study of Atherosclerosis (MESA) participants, free of apparent cardiovascular disease at baseline. RESULTS Elevated Lp(a) was associated with larger absolute increase in CAC volume (3.21 and 4.45 mm3/year higher for Lp(a) ≥30 versus <30 mg/dL, and Lp(a) ≥50 versus <50 mg/dL, respectively), but not relative change in CAC volume. No association was found with change in CAC density when assessing continuous ln-transformed Lp(a). The association between elevated Lp(a) (≥30 mg/dL) and absolute change in CAC volume was greater in participants with higher circulating levels of interleukin-2 soluble receptor α, soluble tumor necrosis factor alpha receptor 1 and fibrinogen (15.33, 11.81 and 7.02 mm3/year in quartile 4, compared to -3.44, -0.59 and 1.91 mm3/year in quartile 1, respectively). No significant interaction was found for other study variables. Similar interactions were seen when assessing Lp(a) levels ≥50 mg/dL. CONCLUSIONS Elevated Lp(a) was associated with an absolute increase in CAC volume, especially in participants with higher levels of selected markers of inflammation and coagulation. These results suggest Lp(a) as a potential biomarker for CAC volume progression.
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Affiliation(s)
- Kwok Leung Ong
- Lipid Research Group, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.
| | | | - Matthew A Allison
- Department of Family Medicine and Public Health, University of California San Diego, La Jolla, CA, USA
| | - Mary Cushman
- Division of Hematology and Oncology, Department of Medicine, Larner College of Medicine at the University of Vermont, Burlington, VT, USA
| | - Parveen K Garg
- Division of Cardiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Michael Y Tsai
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Kerry-Anne Rye
- Lipid Research Group, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Fatiha Tabet
- Lipid Research Group, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.
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Ward NC, Kostner KM, Sullivan DR, Nestel P, Watts GF. Molecular, Population, and Clinical Aspects of Lipoprotein(a): A Bridge Too Far? J Clin Med 2019; 8:E2073. [PMID: 31783529 PMCID: PMC6947201 DOI: 10.3390/jcm8122073] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/15/2019] [Accepted: 11/15/2019] [Indexed: 12/16/2022] Open
Abstract
There is now significant evidence to support an independent causal role for lipoprotein(a) (Lp(a)) as a risk factor for atherosclerotic cardiovascular disease. Plasma Lp(a) concentrations are predominantly determined by genetic factors. However, research into Lp(a) has been hampered by incomplete understanding of its metabolism and proatherogeneic properties and by a lack of suitable animal models. Furthermore, a lack of standardized assays to measure Lp(a) and no universal consensus on optimal plasma levels remain significant obstacles. In addition, there are currently no approved specific therapies that target and lower elevated plasma Lp(a), although there are recent but limited clinical outcome data suggesting benefits of such reduction. Despite this, international guidelines now recognize elevated Lp(a) as a risk enhancing factor for risk reclassification. This review summarises the current literature on Lp(a), including its discovery and recognition as an atherosclerotic cardiovascular disease risk factor, attempts to standardise analytical measurement, interpopulation studies, and emerging therapies for lowering elevated Lp(a) levels.
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Affiliation(s)
- Natalie C. Ward
- School of Public Health, Curtin University, Perth 6102, Australia;
- School of Medicine, University of Western Australia, Perth 6009, Australia
| | - Karam M. Kostner
- Department of Cardiology, Mater Hospital, Brisbane 4104, Australia;
- School of Medicine University of Queensland, Brisbane 4072, Australia
| | - David R. Sullivan
- Medical School, The University of Sydney, Sydney 2006, Australia;
- Charles Perkins Centre, The University of Sydney, Sydney 2006, Australia
- Department of Biochemistry, Royal Prince Alfred Hospital, Sydney 2050, Australia
| | - Paul Nestel
- Baker Heart & Diabetes Institute, Melbourne 3004, Australia;
- Department of Cardiology, The Alfred Hospital, Melbourne 3004, Australia
| | - Gerald F. Watts
- School of Medicine, University of Western Australia, Perth 6009, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth 6000, Australia
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8
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Rawther T, Tabet F. Biology, pathophysiology and current therapies that affect lipoprotein (a) levels. J Mol Cell Cardiol 2019; 131:1-11. [DOI: 10.1016/j.yjmcc.2019.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 03/22/2019] [Accepted: 04/09/2019] [Indexed: 12/11/2022]
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Ma L, Waldmann E, Ooi EMM, Chan DC, Barrett HPR, Watts GF, Parhofer KG. Lipoprotein (a) and Low-density lipoprotein apolipoprotein B metabolism following apheresis in patients with elevated lipoprotein(a) and coronary artery disease. Eur J Clin Invest 2019; 49:e13053. [PMID: 30447089 DOI: 10.1111/eci.13053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 11/04/2018] [Accepted: 11/13/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND Lipoprotein apheresis effectively lowers lipoprotein(a) [Lp(a)] and low-density lipoprotein (LDL) by approximately 60%-70%. The rebound of LDL and Lp(a) particle concentrations following lipoprotein apheresis allows the determination of fractional catabolic rate (FCR) and hence production rate (PR) during non-steady state conditions. We aimed to investigate the kinetics of Lp(a) and LDL apolipoprotein B-100 (apoB) particles in patients with elevated Lp(a) and coronary artery disease undergoing regular apheresis. PATIENTS AND METHODS A cross-sectional study was carried out in 13 patients with elevated Lp(a) concentration (>500 mg/L) and coronary artery disease. Lp(a) and LDL-apoB metabolic parameters, including FCR and PR were derived by the fit of a compartment model to the Lp(a) and LDL-apoB concentration data following lipoprotein apheresis. RESULTS The FCR of Lp(a) was significantly lower than that of LDL-apoB (0.39 [0.31, 0.49] vs 0.57 [0.46, 0.71] pools/day, P = 0.03) with no significant differences in the corresponding PR (14.80 [11.34, 19.32] vs 15.73 [11.93, 20.75] mg/kg/day, P = 0.80). No significant associations were observed between the FCR and PR of Lp(a) and LDL-apoB. CONCLUSIONS In patients with elevated Lp(a), the fractional catabolism of Lp(a) is slower than that of LDL-apoB particles, implying that different metabolic pathways are involved in the catabolism of these lipoproteins. These findings have implications for new therapies for lowering apolipoprotein(a) and apoB to prevent atherosclerotic cardiovascular disease.
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Affiliation(s)
- Louis Ma
- School of Biomedical Science, University of Western Australia, Western Australia, Australia.,School of Medicine, University of Western Australia, Western Australia, Australia
| | - Elisa Waldmann
- Department of Internal Medicine IV, Ludwig-Maximilans-University Munich, Munich, Germany
| | - Esther M M Ooi
- School of Biomedical Science, University of Western Australia, Western Australia, Australia
| | - Dick C Chan
- School of Biomedical Science, University of Western Australia, Western Australia, Australia.,School of Medicine, University of Western Australia, Western Australia, Australia
| | - Hugh P R Barrett
- School of Biomedical Science, University of Western Australia, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Western Australia, Australia.,Department of Cardiology, Lipid Disorders Clinic, Royal Perth Hospital, Western Australia, Australia
| | - Klaus G Parhofer
- Department of Internal Medicine IV, Ludwig-Maximilans-University Munich, Munich, Germany
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Ellis KL, Hooper AJ, Burnett JR, Watts GF. Progress in the care of common inherited atherogenic disorders of apolipoprotein B metabolism. Nat Rev Endocrinol 2016; 12:467-84. [PMID: 27199287 DOI: 10.1038/nrendo.2016.69] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Familial hypercholesterolaemia, familial combined hyperlipidaemia (FCH) and elevated lipoprotein(a) are common, inherited disorders of apolipoprotein B metabolism that markedly accelerate the onset of atherosclerotic cardiovascular disease (ASCVD). These disorders are frequently encountered in clinical lipidology and need to be accurately identified and treated in both index patients and their family members, to prevent the development of premature ASCVD. The optimal screening strategies depend on the patterns of heritability for each condition. Established therapies are widely used along with lifestyle interventions to regulate levels of circulating lipoproteins. New therapeutic strategies are becoming available, and could supplement traditional approaches in the most severe cases, but their long-term cost-effectiveness and safety have yet to be confirmed. We review contemporary developments in the understanding, detection and care of these highly atherogenic disorders of apolipoprotein B metabolism.
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Affiliation(s)
- Katrina L Ellis
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- Centre for Genetic Origins of Health and Disease, The University of Western Australia and Curtin University, 35 Stirling Highway, Crawley, Perth, Western Australia 6009, Australia
| | - Amanda J Hooper
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- School of Pathology and Laboratory Medicine, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, Western Australia 6009, Australia
| | - John R Burnett
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Wellington Street Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Wellington Street Perth, Western Australia, Australia
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Guevara J, Prashad N, Ermolinsky B, Gaubatz JW, Kang D, Schwarzbach AE, Loose DS, Guevara NV. Apo B100 similarities to viral proteins suggest basis for LDL-DNA binding and transfection capacity. J Lipid Res 2010; 51:1704-18. [PMID: 20173184 DOI: 10.1194/jlr.m003277] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
LDL mediates transfection with plasmid DNA in a variety of cell types in vitro and in several tissues in vivo in the rat. The transfection capacity of LDL is based on apo B100, as arginine/lysine clusters, suggestive of nucleic acid-binding domains and nuclear localization signal sequences, are present throughout the molecule. Apo E may also contribute to this capacity because of its similarity to the Dengue virus capsid proteins and its ability to bind DNA. Synthetic peptides representing two apo B100 regions with prominent Arg/Lys clusters were shown to bind DNA. Region 1 (0014Lys-Ser0160) shares sequence motifs present in DNA binding domains of Interferon Regulatory Factors and Flaviviridae capsid/core proteins. It also contains a close analog of the B/E receptor ligand of apo E. Region 1 peptides, B1-1 (0014Lys-Glu0054) and B1-2 (0055Leu-Ala0096), mediate transfection of HeLa cells but are cytotoxic. Region 2 (3313Asp-Thr3431), containing the known B/E receptor ligand, shares analog motifs with the human herpesvirus 5 immediate-early transcriptional regulator (UL122) and Flaviviridae NS3 helicases. Region 2 peptides, B2-1 (3313Asp-Glu3355), and B2-2 (3356Gly-Thr3431) are ineffective in cell transfection and are noncytotoxic. These results confirm the role of LDL as a natural transfection vector in vivo, a capacity imparted by the apo B100, and suggest a basis for Flaviviridae cell entry.
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Affiliation(s)
- Juan Guevara
- Department of Physics and Astronomy, University of Texas Brownsville/Texas Southmost College, Brownsville, TX 78520, USA
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Apolipoprotein(a) stimulates vascular endothelial cell growth and migration and signals through integrin alphaVbeta3. Biochem J 2009; 418:325-36. [PMID: 18821851 DOI: 10.1042/bj20080744] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Elevated plasma concentrations of Lp(a) [lipoprotein(a)] are an emerging risk factor for atherothrombotic disease. Apo(a) [apolipoprotein(a)], the unique glycoprotein component of Lp(a), contains tandem repeats of a plasminogen kringle (K) IV-like domain. In the light of recent studies suggesting that apo(a)/Lp(a) affects endothelial function, we evaluated the effects of apo(a)/Lp(a) on growth and migration of cultured HUVECs (human umbilical-vein endothelial cells). Two full-length r-apo(a) [recombinant apo(a)] variants (12K and 17K), as well as Lp(a), were able to stimulate HUVEC growth and migration to a comparable extent; 17K r-apo(a) also decreased the levels of total and active transforming growth factor-beta secreted by these cells. Using additional r-apo(a) variants corresponding to deletions and/or site-directed mutants of various kringle domains in the molecule, we were able to determine that the observed effects of full-length r-apo(a) on HUVECs were dependent on the presence of a functional lysine-binding site(s) in the apo(a) molecule. With respect to signalling events elicited by apo(a) in HUVECs, we found that 17K treatment of the cells increased the phosphorylation level of FAK (focal adhesion kinase) and MAPKs (mitogen-activated protein kinases), including ERK (extracellular-signal-regulated kinase), p38 and JNK (c-Jun N-terminal kinase). In addition, we showed that LM609, the function-blocking antibody to integrin alphaVbeta3, abrogated the effects of 17K r-apo(a) and Lp(a) on HUVECs. Taken together, the results of the present study suggest that the apo(a) component of Lp(a) signals through integrin alphaVbeta3 to activate endothelial cells.
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13
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Lippi G, Franchini M, Salvagno GL, Guidi GC. Lipoprotein[a] and cancer: Anti-neoplastic effect besides its cardiovascular potency. Cancer Treat Rev 2007; 33:427-36. [PMID: 17442497 DOI: 10.1016/j.ctrv.2007.02.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2007] [Revised: 02/26/2007] [Accepted: 02/26/2007] [Indexed: 11/24/2022]
Abstract
While the death rate from cancer has substantially decreased over the past decade, the search for effective and tolerable therapies is a great challenge as yet. The evidence that malignant cells cannot grow to a clinically detectable tumor mass and spread in the absence of an adequate vascular support, has opened a new area of research towards the selective inhibition or even destruction of tumor vessels. Angiostatin and angiostatin-related proteins are a family of specific angiogenesis inhibitors produced by tumors from a family of naturally occurring proteins, which also includes plasminogen and lipoprotein[a]. The anti-angiogenic activity of these proteins resides in cryptic and highly-repetitive molecular domains hidden within the protein moiety, called kringles. Lipoprotein[a] is an intriguing molecule consisting of a low-density lipoprotein core in addition to the covalently bound apolipoprotein[a]. Apolipoprotein[a] is characterized by an inactive protease domain, a single copy of the plasminogen kringle V and multiple repeats of domains homologous to the plasminogen kringle IV. Reliable studies on animal models indicate that the proteolytic break-down products of apolipoprotein[a] would posses anti-angiogenic and anti-tumoral properties both in vitro and in vivo, a premise to develop novel therapeutic modalities which may efficiently suppress tumor growth and metastasis. This review is focused on the biochemical structure, metabolism and the anti-angiogenic activity of this unique and elusive kringle-containing lipoprotein.
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Affiliation(s)
- Giuseppe Lippi
- Sezione di Chimica e Microscopia Clinica, Dipartimento di Scienze Morfologico-Biomediche, Università degli Studi di Verona, Ospedale Policlinico G.B. Rossi, Piazzale Scuro 10, 37134 Verona, Italy.
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14
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Sotiriou SN, Orlova VV, Al-Fakhri N, Ihanus E, Economopoulou M, Isermann B, Bdeir K, Nawroth PP, Preissner KT, Gahmberg CG, Koschinsky ML, Chavakis T. Lipoprotein(a) in atherosclerotic plaques recruits inflammatory cells through interaction with Mac‐1 integrin. FASEB J 2006; 20:559-61. [PMID: 16403785 DOI: 10.1096/fj.05-4857fje] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lipoprotein(a) [Lp(a)], consisting of LDL and the unique constituent apolipoprotein(a) [apo(a)], which contains multiple repeats resembling plasminogen kringle 4, is considered a risk factor for the development of atherosclerotic disorders. However, the underlying mechanisms for the atherogenicity of Lp(a) are not completely understood. Here, we define a novel function of Lp(a) in promoting inflammatory cell recruitment that may contribute to its atherogenicity. Through its apo(a) moiety Lp(a) specifically interacts with the beta2-integrin Mac-1, thereby promoting the adhesion of monocytes and their transendothelial migration in a Mac-1-dependent manner. Interestingly, the interaction between Mac-1 and Lp(a) was strengthened in the presence of proatherogenic homocysteine and was blocked by plasminogen/angiostatin kringle 4. Through its interaction with Mac-1, Lp(a) induced activation of the proinflammatory transcription factor NFkappaB, as well as the NFkappaB-related expression of prothrombotic tissue factor. In atherosclerotic coronary arteries Lp(a) was found to be localized in close proximity to Mac-1 on infiltrating mononuclear cells. Taken together, our data demonstrate that Lp(a), via its apo(a) moiety, is a ligand for the beta2-integrin Mac-1, thereby facilitating inflammatory cell recruitment to atherosclerotic plaques. These observations suggest a novel mechanism for the atherogenic properties of Lp(a).
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15
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Espinosa IL, McNeal CJ, Macfarlane RD. Method for Lipoprotein(a) Density Profiling by BiEDTA Differential Density Lipoprotein Ultracentrifugation. Anal Chem 2005; 78:438-44. [PMID: 16408925 DOI: 10.1021/ac050962u] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this article, we demonstrate the analytical power of linking density gradient ultracentrifugation with affinity separations. Here we address some of the analytical challenges in the study of lipoprotein(a), (Lp(a)). The mean density distribution of Lp(a) was determined by a differential density lipoprotein profile (DDLP). For DDLP, the lipoprotein density distribution of a serum sample with elevated Lp(a) levels was determined by ultracentrifugation using a BiEDTA complex as a density gradient. Lp(a) was removed from a second aliquot of the same serum sample by carbohydrate affinity using wheat germ agglutinin (WGA). WGA was demonstrated to have high specificity for Lp(a) in a serum sample. This sample was ultracentrifuged to obtain a lipoprotein density distribution in the absence of Lp(a). A DDLP was obtained after subtracting the Lp(a)-depleted lipoprotein density profile from the untreated lipoprotein density profile. The DDLP methodology reported herein gives relevant information of the lipoproteins in serum such as density, isoform, and subclass characteristics. Lp(a) was quantitatively isolated from serum with a recovery efficiency of 82%. Lp(a) was purified by ultracentrifugation. Lp(a) retained its inherent density (1.086 g/mL) and immunoreactivity. The major outcome of this research was the effectiveness of using affinity separations coupled with density ultracentrifugation for the isolation of pure Lp(a) from serum and its isoform characterization based on density by DDLP.
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Affiliation(s)
- I Leticia Espinosa
- Laboratory for Cardiovascular Chemistry, Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, USA
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16
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Abstract
Fibrinogen is a large, complex, fibrous glycoprotein with three pairs of polypeptide chains linked together by 29 disulfide bonds. It is 45 nm in length, with globular domains at each end and in the middle connected by alpha-helical coiled-coil rods. Both strongly and weakly bound calcium ions are important for maintenance of fibrinogen's structure and functions. The fibrinopeptides, which are in the central region, are cleaved by thrombin to convert soluble fibrinogen to insoluble fibrin polymer, via intermolecular interactions of the "knobs" exposed by fibrinopeptide removal with "holes" always exposed at the ends of the molecules. Fibrin monomers polymerize via these specific and tightly controlled binding interactions to make half-staggered oligomers that lengthen into protofibrils. The protofibrils aggregate laterally to make fibers, which then branch to yield a three-dimensional network-the fibrin clot-essential for hemostasis. X-ray crystallographic structures of portions of fibrinogen have provided some details on how these interactions occur. Finally, the transglutaminase, Factor XIIIa, covalently binds specific glutamine residues in one fibrin molecule to lysine residues in another via isopeptide bonds, stabilizing the clot against mechanical, chemical, and proteolytic insults. The gene regulation of fibrinogen synthesis and its assembly into multichain complexes proceed via a series of well-defined steps. Alternate splicing of two of the chains yields common variant molecular isoforms. The mechanical properties of clots, which can be quite variable, are essential to fibrin's functions in hemostasis and wound healing. The fibrinolytic system, with the zymogen plasminogen binding to fibrin together with tissue-type plasminogen activator to promote activation to the active enzyme plasmin, results in digestion of fibrin at specific lysine residues. Fibrin(ogen) also specifically binds a variety of other proteins, including fibronectin, albumin, thrombospondin, von Willebrand factor, fibulin, fibroblast growth factor-2, vascular endothelial growth factor, and interleukin-1. Studies of naturally occurring dysfibrinogenemias and variant molecules have increased our understanding of fibrinogen's functions. Fibrinogen binds to activated alphaIIbbeta3 integrin on the platelet surface, forming bridges responsible for platelet aggregation in hemostasis, and also has important adhesive and inflammatory functions through specific interactions with other cells. Fibrinogen-like domains originated early in evolution, and it is likely that their specific and tightly controlled intermolecular interactions are involved in other aspects of cellular function and developmental biology.
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Affiliation(s)
- John W Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6058, USA
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Myers JC, Li D, Amenta PS, Clark CC, Nagaswami C, Weisel JW. Type XIX collagen purified from human umbilical cord is characterized by multiple sharp kinks delineating collagenous subdomains and by intermolecular aggregates via globular, disulfide-linked, and heparin-binding amino termini. J Biol Chem 2003; 278:32047-57. [PMID: 12788917 DOI: 10.1074/jbc.m304629200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Type XIX collagen was discovered from the sequence of rhabdomyosarcoma cDNA clones. The chain is composed of a 268-residue amino terminus, an 832-residue discontinuous collagenous region, and a 19-residue carboxyl peptide. Light microscopy immunohistochemistry of adult human tissues demonstrated that type XIX is localized in vascular, neuronal, mesenchymal, and some epithelial basement membrane zones. It also appears to be involved in events linked to skeletal myogenesis. In this report, we have presented the first direct evidence for the molecular structure of type XIX collagen. Using human umbilical cord, native type XIX was purified by neutral salt extraction and by ion exchange and antibody affinity chromatography. Type XIX was found to represent only approximately 10(-6)% of the dry weight of tissue, making it by far the least abundant collagen ever isolated. Transmission electron microscopy after rotary shadowing revealed the appearance of rodlike structures with multiple sharp bends, a small nodule at one end of the molecule, and a total length of 240 nm. Domain-specific antibodies were used to identify the nodule as the noncollagenous amino terminus, whereas the location of most kinks corresponds to major interruptions separating the five collagenous subdomains. More than half of the type XIX molecules observed were present in oligomers of different size and complexity, resulting from association of the amino-terminal domains. Biochemical analysis demonstrated that these supramolecular aggregates are dependent upon and/or stabilized by intermolecular disulfide cross-links and that the globular amino terminus contains a high affinity, heparin-binding site. The polymorphic conformational states of this rare collagen, and its ability to self-assemble into a higher order structure provide focal points for future determination of biologically significant functions in cell-cell and/or cell-matrix interactions.
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Affiliation(s)
- Jeanne C Myers
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
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18
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Becker L, Webb BA, Chitayat S, Nesheim ME, Koschinsky ML. A ligand-induced conformational change in apolipoprotein(a) enhances covalent Lp(a) formation. J Biol Chem 2003; 278:14074-81. [PMID: 12566443 DOI: 10.1074/jbc.m212855200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lipoprotein(a) (Lp(a)) assembly proceeds via a two-step mechanism in which initial non-covalent interactions between apolipoprotein(a) (apo(a)) and low density lipoprotein precede disulfide bond formation. In this study, we used analytical ultracentrifugation, differential scanning calorimetry, and intrinsic fluorescence to demonstrate that in the presence of the lysine analog epsilon-aminocaproic acid, apo(a) undergoes a substantial conformational change from a "closed" to an "open" structure that is characterized by an increase in the hydrodynamic radius (approximately 10%), an alteration in domain stability, as well as a decrease in tryptophan fluorescence. Although epsilon-aminocaproic acid is a well characterized inhibitor of the non-covalent interaction between apo(a) and low density lipoprotein, we report the novel observation that this ligand at low concentrations (100 microm-1 mm) significantly enhances covalent Lp(a) assembly by altering the conformation of apo(a). We developed a model for the kinetics of Lp(a) assembly that incorporates the conformational change as a determinant of the efficiency of the process; this model quantitatively explains our experimental observations. Interestingly, an analogous conformational change has been previously described for plasminogen resulting in an increase in the hydrodynamic radius, an increase in tryptophan fluorescence, and an acceleration of the rate of plasminogen activation. Although the functions of apo(a) and plasminogen have diverged considerably, elements of structural and conformational homology have been retained leading to similar regulation of two unrelated biological processes.
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Affiliation(s)
- Lev Becker
- Department of Biochemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada
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Hill BC, Becker L, Anand V, Kusmierczyk A, Marcovina SM, Rahman MN, Gabel BR, Jia Z, Boffa MB, Koschinsky ML. A role for apolipoprotein(a) in protection of the low-density lipoprotein component of lipoprotein(a) from copper-mediated oxidation. Arch Biochem Biophys 2003; 412:186-95. [PMID: 12667482 DOI: 10.1016/s0003-9861(03)00032-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Low-density lipoprotein (LDL) oxidation is stimulated by copper. Addition of a recombinant form of apolipoprotein(a) (apo(a); the distinguishing protein component of lipoprotein(a)) containing 17 plasminogen kringle IV-like domains (17K r-apo(a)) protects LDL against oxidation by copper. Protection is specific to apo(a) and is not achieved by plasminogen or serum albumin. When Cu(2+) is added to 17K r-apo(a), its intrinsic fluorescence is quenched in a concentration-dependent and saturable manner. Quenching is unchanged whether performed aerobically or anaerobically and is reversible by ethylenediaminetetraacetate, suggesting that it is due to equilibrium binding of Cu(2+) and not to oxidative destruction of tryptophan residues. The fluorescence change exhibits a sigmoid dependence on copper concentration, and time courses of quenching are complex. At copper concentrations below 10 microM there is little quenching, whereas above 10 microM quenching proceeds immediately as a double-exponential decay. The affinity and kinetics of copper binding to 17K r-apo(a) are diminished in the presence of the lysine analogue epsilon -aminocaproic acid. We propose that copper binding to the kringle domains of 17K is mediated by a His-X-His sequence that is located about 5A from the closest tryptophan residue of the lysine binding pocket. Copper binding may account for the natural resistance to copper-mediated oxidation of lipoprotein(a) relative to LDL that has been previously reported and for the protection afforded by apo(a) from copper-mediated oxidation of LDL that we describe in the present study.
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Affiliation(s)
- Bruce C Hill
- Department of Biochemistry, Queen's University, Kingston, Ont, Canada K7L 3N6
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20
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Abstract
Lipoprotein(a) is a cholesterol-enriched lipoprotein, consisting of a covalent linkage joining the unique and highly polymorphic apolipoprotein(a) to apolipoprotein B100, the main protein moiety of low-density lipoproteins. Although the concentration of lipoprotein(a) in humans is mostly genetically determined, acquired disorders might influence synthesis and catabolism of the particle. Raised concentration of lipoprotein(a) has been acknowledged as a leading inherited risk factor for both premature and advanced atherosclerosis at different vascular sites. The strong structural homologies with plasminogen and low-density lipoproteins suggest that lipoprotein(a) might represent the ideal bridge between the fields of atherosclerosis and thrombosis in the pathogenesis of vascular occlusive disorders. Unfortunately, the exact mechanisms by which lipoprotein(a) promotes, accelerates, and complicates atherosclerosis are only partially understood. In some clinical settings, such as in patients at exceptionally low risk for cardiovascular disease, the potential regenerative and antineoplastic properties of lipoprotein(a) might paradoxically counterbalance its athero-thrombogenicity, as attested by the compatibility between raised plasma lipoprotein(a) levels and longevity.
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Affiliation(s)
- Giuseppe Lippi
- Istituto di Chimica e Microscopia Clinica, Dipartimento di Scienze Morfologiche e Biomediche, Università degli Studi di Verona, Verona, Italy
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21
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Kang C, Dominguez M, Loyau S, Miyata T, Durlach V, Anglés-Cano E. Lp(a) particles mold fibrin-binding properties of apo(a) in size-dependent manner: a study with different-length recombinant apo(a), native Lp(a), and monoclonal antibody. Arterioscler Thromb Vasc Biol 2002; 22:1232-8. [PMID: 12117743 DOI: 10.1161/01.atv.0000021144.87870.c8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Small-sized apolipoprotein(a) [apo(a)] isoforms with high antifibrinolytic activity are frequently found in cardiovascular diseases, suggesting a role for apo(a) size in atherothrombosis. To test this hypothesis, we sought to characterize the lysine (fibrin)-binding function of isolated apo(a) of variable sizes. METHODS AND RESULTS Recombinant apo(a) [r-apo(a)] preparations consisting of 10 to 34 kringles and a monoclonal antibody that neutralizes the lysine-binding function were produced and used in parallel with lipoprotein(a) [Lp(a)] particles isolated from plasma in fibrin-binding studies. All r-apo(a) preparations displayed similar affinity and specificity for lysine residues on fibrin regardless of size (K(d) 3.6+/-0.3 nmol/L) and inhibited the binding of plasminogen with a similar intensity (IC50 16.8+/-5.4 nmol/L). In contrast, native Lp(a) particles displayed fibrin affinities that were in inverse relationship with the apo(a) kringle number. Thus, a 15-kringle apo(a) separated from Lp(a) and a 34-kringle r-apo(a) displayed an affinity for fibrin that was higher than that in the corresponding particles (K(d) 2.5 versus 10.5 nmol/L and K(d) 3.8 versus 541 nmol/L, respectively). However, fibrin-binding specificity of the r-apo(a) preparations and the Lp(a) particles was efficiently neutralized (IC50 0.07 and 4 nmol/L) by a monoclonal antibody directed against the lysine-binding function of kringle IV-10. CONCLUSIONS Our data indicate that fibrin binding is an intrinsic property of apo(a) modulated by the composite structure of the Lp(a) particle.
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Affiliation(s)
- Chantal Kang
- INSERM U460, Faculté de Médecine Xavier Bichat, Paris, France
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