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Electronegative LDL Is Associated with Plaque Vulnerability in Patients with Ischemic Stroke and Carotid Atherosclerosis. Antioxidants (Basel) 2023; 12:antiox12020438. [PMID: 36829998 PMCID: PMC9952764 DOI: 10.3390/antiox12020438] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Owing to the high risk of recurrence, identifying indicators of carotid plaque vulnerability in atherothrombotic ischemic stroke is essential. In this study, we aimed to identify modified LDLs and antioxidant enzymes associated with plaque vulnerability in plasma from patients with a recent ischemic stroke and carotid atherosclerosis. Patients underwent an ultrasound, a CT-angiography, and an 18F-FDG PET. A blood sample was obtained from patients (n = 64, 57.8% with stenosis ≥50%) and healthy controls (n = 24). Compared to the controls, patients showed lower levels of total cholesterol, LDL cholesterol, HDL cholesterol, apolipoprotein B (apoB), apoA-I, apoA-II, and apoE, and higher levels of apoJ. Patients showed lower platelet-activating factor acetylhydrolase (PAF-AH) and paraoxonase-1 (PON-1) enzymatic activities in HDL, and higher plasma levels of oxidized LDL (oxLDL) and electronegative LDL (LDL(-)). The only difference between patients with stenosis ≥50% and <50% was the proportion of LDL(-). In a multivariable logistic regression analysis, the levels of LDL(-), but not of oxLDL, were independently associated with the degree of carotid stenosis (OR: 5.40, CI: 1.15-25.44, p < 0.033), the presence of hypoechoic plaque (OR: 7.52, CI: 1.26-44.83, p < 0.027), and of diffuse neovessels (OR: 10.77, CI: 1.21-95.93, p < 0.033), indicating that an increased proportion of LDL(-) is associated with vulnerable atherosclerotic plaque.
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Chen DY, Sawamura T, Dixon RAF, Sánchez-Quesada JL, Chen CH. Autoimmune Rheumatic Diseases: An Update on the Role of Atherogenic Electronegative LDL and Potential Therapeutic Strategies. J Clin Med 2021; 10:1992. [PMID: 34066436 PMCID: PMC8124242 DOI: 10.3390/jcm10091992] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/20/2021] [Accepted: 05/02/2021] [Indexed: 12/12/2022] Open
Abstract
Atherosclerosis has been linked with an increased risk of atherosclerotic cardiovascular disease (ASCVD). Autoimmune rheumatic diseases (AIRDs) are associated with accelerated atherosclerosis and ASCVD. However, the mechanisms underlying the high ASCVD burden in patients with AIRDs cannot be explained only by conventional risk factors despite disease-specific factors and chronic inflammation. Nevertheless, the normal levels of plasma low-density lipoprotein (LDL) cholesterol observed in most patients with AIRDs do not exclude the possibility of increased LDL atherogenicity. By using anion-exchange chromatography, human LDL can be divided into five increasingly electronegative subfractions, L1 to L5, or into electropositive and electronegative counterparts, LDL (+) and LDL (-). Electronegative L5 and LDL (-) have similar chemical compositions and can induce adverse inflammatory reactions in vascular cells. Notably, the percentage of L5 or LDL (-) in total LDL is increased in normolipidemic patients with AIRDs. Electronegative L5 and LDL (-) are not recognized by the normal LDL receptor but instead signal through the lectin-like oxidized LDL receptor 1 (LOX-1) to activate inflammasomes involving interleukin 1β (IL-1β). Here, we describe the detailed mechanisms of AIRD-related ASCVD mediated by L5 or LDL (-) and discuss the potential targeting of LOX-1 or IL-1β signaling as new therapeutic modalities for these diseases.
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Affiliation(s)
- Der-Yuan Chen
- Translational Medicine Center, China Medical University Hospital, Taichung 404, Taiwan;
- Rheumatology and Immunology Center, China Medical University Hospital, Taichung 404, Taiwan
- College of Medicine, China Medical University, Taichung 404, Taiwan
| | - Tatsuya Sawamura
- Department of Molecular Pathophysiology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan;
- Department of Life Innovation, Institute for Biomedical Sciences, Shinshu University, Matsumoto 390-8621, Japan
| | - Richard A. F. Dixon
- Molecular Cardiology Research Laboratories, Texas Heart Institute, Houston, TX 77030, USA;
| | - José Luis Sánchez-Quesada
- Cardiovascular Biochemistry Group, Biomedical Research Institute IIB Sant Pau, 08041 Barcelona, Spain;
- CIBER of Diabetes and Metabolic Diseases (CIBERDEM), 08041 Barcelona, Spain
| | - Chu-Huang Chen
- Department of Life Innovation, Institute for Biomedical Sciences, Shinshu University, Matsumoto 390-8621, Japan
- Vascular and Medicinal Research, Texas Heart Institute, Houston, TX 77030, USA
- New York Heart Research Foundation, Mineola, NY 11501, USA
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Akyol O, Chowdhury I, Akyol HR, Tessier K, Vural H, Akyol S. Why are cardiovascular diseases more common among patients with severe mental illness? The potential involvement of electronegative low-density lipoprotein (LDL) L5. Med Hypotheses 2020; 142:109821. [PMID: 32417641 DOI: 10.1016/j.mehy.2020.109821] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/22/2020] [Accepted: 05/05/2020] [Indexed: 02/07/2023]
Abstract
Despite tremendous efforts of experimental and clinical studies and knowledge, the pathophysiology of severe mental illness (SMI), including bipolar disorder (BD), unipolar depression (mood disorders, MD), and schizophrenia (SCZ), remains poorly understood. Besides their chronic course and high prevalence in society, mental and somatic comorbidities are really serious problems; patients with these disorders have increased risk of cardiovascular (CV) diseases (CVD) including coronary artery diseases (CAD, i.e. myocardial infarction and angina), stroke, sudden cardiac death, hypertension, cardiomyopathy, arrhythmia, and thromboembolic disease. Although it is determined that triglycerides, cholesterol, glucose, and low-density lipoprotein (LDL) levels are increased in MD and SCZ, the underlying reason remains unknown. Considering this, we propose that electronegative LDL (L5) is probably the main crucial element to understanding CVD induced by SMI and to discovering novel remedial approaches for these diseases. When it is hypothesized that L5 is greatly presupposed in CV system abnormalities, it follows that the anti-L5 therapies and even antioxidant treatment options may open new therapeutic opportunities to prevent CVD diseases secondary to SMI. In this review article, we tried to bring a very original subject to the attention of readers who are interested in lipoprotein metabolism in terms of experimental, clinical, and cell culture studies that corroborate the involvement of L5 in physiopathology of CVD secondary to SMI and also the new therapeutic approaches for these disorders.
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Affiliation(s)
- Omer Akyol
- Michigan Math & Science Academy, Department of Science, Warren, MI, USA.
| | - Imtihan Chowdhury
- Michigan Math & Science Academy, High School, 11th grade, Warren, MI, USA
| | - Hafsa Rana Akyol
- Illinois Institute of Technology, Biology, Sophomore, Chicago, IL, USA
| | - Kylie Tessier
- Michigan Math & Science Academy, High School, 11th grade, Warren, MI, USA
| | - Huseyin Vural
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry, RWTH University Hospital Aachen, Aachen, Germany
| | - Sumeyya Akyol
- Beaumont Health, Beaumont Research Institute, Royal Oak, MI, USA
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Estruch M, Miñambres I, Sanchez-Quesada JL, Soler M, Pérez A, Ordoñez-Llanos J, Benitez S. Increased inflammatory effect of electronegative LDL and decreased protection by HDL in type 2 diabetic patients. Atherosclerosis 2017; 265:292-298. [PMID: 28734591 DOI: 10.1016/j.atherosclerosis.2017.07.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 07/04/2017] [Accepted: 07/12/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND AIMS Type 2 diabetic patients have an increased proportion of electronegative low-density lipoprotein (LDL(-)), an inflammatory LDL subfraction present in blood, and dysfunctional high-density lipoprotein (HDL). We aimed at examining the inflammatory effect of LDL(-) on monocytes and the counteracting effect of HDL in the context of type 2 diabetes. METHODS This was a cross-sectional study in which the population comprised 3 groups (n = 12 in each group): type 2 diabetic patients with good glycaemic control (GC-T2DM patients), type 2 diabetic patients with poor glycaemic control (PC-T2DM), and a control group. Total LDL, HDL, and monocytes were isolated from plasma of these subjects. LDL(-) was isolated from total LDL by anion-exchange chromatography. LDL(-) from the three groups of subjects was added to monocytes in the presence or absence of HDL, and cytokines released by monocytes were quantified by ELISA. RESULTS LDL(-) proportion and plasma inflammatory markers were increased in PC-T2DM patients. LDL(-) from PC-T2DM patients induced the highest IL1β, IL6, and IL10 release in monocytes compared to LDL(-) from GC-T2DM and healthy subjects, and presented the highest content of non-esterified fatty acids (NEFA). In turn, HDL from PC-T2DM patients showed the lowest ability to inhibit LDL(-)-induced cytokine release in parallel to an impaired ability to decrease NEFA content in LDL(-). CONCLUSIONS Our findings show an imbalance in the pro- and anti-inflammatory effects of lipoproteins from T2DM patients, particularly in PC-T2DM.
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Affiliation(s)
- Montserrat Estruch
- Cardiovascular Biochemistry, Biomedical Research Institute Sant Pau (IIB-Sant Pau), C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain
| | - Inka Miñambres
- Endocrinology and Nutrition Department, Hospital de la Santa Creu i Sant Pau Barcelona, C/Sant Quintí 89, 08026 Barcelona, Spain
| | - Jose Luis Sanchez-Quesada
- Cardiovascular Biochemistry, Biomedical Research Institute Sant Pau (IIB-Sant Pau), C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain; Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain
| | - Marta Soler
- Flow Cytometry Platform, Biomedical Research Institute Sant Pau (IIB-Sant Pau), C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain
| | - Antonio Pérez
- Endocrinology and Nutrition Department, Hospital de la Santa Creu i Sant Pau Barcelona, C/Sant Quintí 89, 08026 Barcelona, Spain
| | - Jordi Ordoñez-Llanos
- Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain; Biochemistry Department, Hospital de la Santa Creu i Sant Pau Barcelona, C/Sant Quintí 89, 08026 Barcelona, Spain
| | - Sonia Benitez
- Cardiovascular Biochemistry, Biomedical Research Institute Sant Pau (IIB-Sant Pau), C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain; Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain.
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Cavalcante MF, Kazuma SM, Bender EA, Adorne MD, Ullian M, Veras MM, Saldiva PHN, Maranhão AQ, Guterres SS, Pohlmann AR, Abdalla DSP. A nanoformulation containing a scFv reactive to electronegative LDL inhibits atherosclerosis in LDL receptor knockout mice. Eur J Pharm Biopharm 2016; 107:120-9. [PMID: 27378286 DOI: 10.1016/j.ejpb.2016.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 06/24/2016] [Accepted: 07/01/2016] [Indexed: 01/21/2023]
Abstract
Atherosclerosis is a chronic inflammatory disease responsible for the majority of cases of myocardial infarction and ischemic stroke. The electronegative low-density lipoprotein, a modified subfraction of native LDL, is pro-inflammatory and plays an important role in atherogenesis. To investigate the effects of a nanoformulation (scFv anti-LDL(-)-MCMN-Zn) containing a scFv reactive to LDL(-) on the inhibition of atherosclerosis, its toxicity was evaluated in vitro and in vivo and further it was also administered weekly to LDL receptor knockout mice. The scFv anti-LDL(-)-MCMN-Zn nanoformulation did not induce cell death in RAW 264.7 macrophages and HUVECs. The 5mg/kg dose of scFv anti-LDL(-)-MCMN-Zn did not cause any typical signs of toxicity and it was chosen for the evaluation of its atheroprotective effect in Ldlr(-/-) mice. This nanoformulation significantly decreased the atherosclerotic lesion area at the aortic sinus, compared with that in untreated mice. In addition, the Il1b mRNA expression and CD14 protein expression were downregulated in the atherosclerotic lesions at the aortic arch of Ldlr(-/-) mice treated with scFv anti-LDL(-)-MCMN-Zn. Thus, the scFv anti-LDL(-)-MCMN-Zn nanoformulation inhibited the progression of atherosclerotic lesions, indicating its potential use in a future therapeutic strategy for atherosclerosis.
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Affiliation(s)
- Marcela Frota Cavalcante
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Soraya Megumi Kazuma
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Eduardo André Bender
- Department of Organic Chemistry, Chemistry Institute, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Márcia Duarte Adorne
- Department of Organic Chemistry, Chemistry Institute, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Mayara Ullian
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Mariana Matera Veras
- LIM5, Department of Pathology, Medicine School, University of Sao Paulo, Sao Paulo, SP, Brazil
| | | | - Andrea Queiroz Maranhão
- Molecular Immunology Laboratory, Department of Cell Biology, University of Brasilia, Brasilia, Distrito Federal, Brazil
| | - Silvia Stanisçuaski Guterres
- Department of Production and Control of Medicines, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Adriana Raffin Pohlmann
- Department of Organic Chemistry, Chemistry Institute, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Dulcineia Saes Parra Abdalla
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil.
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Estruch M, Sanchez-Quesada JL, Ordoñez-Llanos J, Benitez S. Inflammatory intracellular pathways activated by electronegative LDL in monocytes. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:963-969. [PMID: 27235719 DOI: 10.1016/j.bbalip.2016.05.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 05/10/2016] [Accepted: 05/23/2016] [Indexed: 12/12/2022]
Abstract
AIMS Electronegative LDL (LDL(-)) is a plasma LDL subfraction that induces cytokine release in monocytes through toll-like receptor 4 (TLR4) activation. However, the intracellular pathways induced by LDL(-) downstream TLR4 activation are unknown. We aimed to identify the pathways activated by LDL(-) leading to cytokine release in monocytes. METHODS AND RESULTS We determined LDL(-)-induced activation of several intracellular kinases in protein extracts from monocytes using a multikinase ELISA array. LDL(-) induced higher p38 mitogen-activated protein kinase (MAPK) phosphorylation than native LDL. This was corroborated by a specific cell-based assay and it was dependent on TLR4 and phosphoinositide 3-kinase (PI3k)/Akt pathway. P38 MAPK activation was involved in cytokine release promoted by LDL(-). A specific ELISA showed that LDL(-) activated cAMP response-element binding (CREB) in a p38 MAPK dependent manner. P38 MAPK was also involved in the nuclear factor kappa-B (NF-kB) and activating protein-1 (AP-1) activation by LDL(-). We found that NF-kB, AP-1 and CREB inhibitors decreased LDL(-)-induced cytokine release, mainly on MCP1, IL6 and IL10 release, respectively. CONCLUSIONS LDL(-) promotes p38 MAPK phosphorylation through TLR4 and PI3k/Akt pathways. Phosphorylation of p38 MAPK is involved in NF-kB, AP-1 and CREB activation, leading to LDL(-)-induced cytokine release in monocytes.
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Affiliation(s)
- Montserrat Estruch
- Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain, C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain.
| | - Jose Luis Sanchez-Quesada
- Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain, C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain; Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain.
| | - Jordi Ordoñez-Llanos
- Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain; Biochemistry Department, Hospital de la Santa Creu i Sant Pau Barcelona, C/Sant Quintí 89, 08026 Barcelona, Spain.
| | - Sonia Benitez
- Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain, C/Sant Antoni M. Claret 167, 08025 Barcelona, Spain; Molecular Biology and Biochemistry Department, Universitat Autònoma de Barcelona (UAB) Faculty of Medicine, Building M. Cerdanyola del Vallès, Spain.
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Silva ITD, Mello APDQ, Sanches LB, Abdalla DSP, Damasceno NRT. Is plasma alpha-tocopherol associated with electronegative LDL in obese adolescents? J Nutr Sci Vitaminol (Tokyo) 2014; 59:100-7. [PMID: 23727639 DOI: 10.3177/jnsv.59.100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Obesity has increased in children and adolescents. What is reflected in the early occurrence of cardiometabolic alterations, like hypertension and type 2 diabetes, where the oxLDL formation is stimulated. Various studies have shown that plasma α-tocopherol (α-TP) can protect LDL against oxidation. Nevertheless, the action of plasma α-TP in cardiovascular diseases remains controversial. We conducted a cross-sectional study to evaluate plasma α-TP and its impact on the concentration of LDL(-). Adolescents (n=150) of both sexes were classified into three groups: healthy weight (HW; 50%), overweight (OV; 22%), and obese (OB; 28%). Lipid profile, LDL(-), anti-oxLDL and anti-LDL(-) antibodies, CRP (ELISA) and plasma α-TP (HPLC) were analyzed. Demographic, anthropometric, and food intake data were evaluated. Crude and energy-adjusted intake of vitamin E in the OB group were higher than in the HW group (p<0.001). Crude and energy-adjusted vitamin E intakes were not correlated with plasma α-TP (r=-0.07; p=0.412 and r=-0.064; p=0.467, respectively). Subjects in the OB group had higher TC and LDL-C and lower HDL-C than in the HW and OV groups. C-reactive protein and anti-oxLDL antibodies changed as a function of BMI. The impact of obesity was reinforced by high values for LDL(-) and low content of plasma α-TP in comparison with the HW (p<0.001) and OV groups (p=0.03). This negative profile was maintained for the ratio between α-TP and TC or LDL-C. Plasma α-TP, α-TP/TC and α-TP/LDL-C were negatively associated with LDL(-) and other cardiometabolic risk factors (BMI, WC, AC and anti-oxLDL). Our results demonstrate that obesity in adolescents is associated with high levels of LDL(-) and low plasma α-TP content.
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Affiliation(s)
- Isis Tande da Silva
- Department of Nutrition, School of Public Health, University of São Paulo, SP, Brazil.
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Electronegative LDL: a circulating modified LDL with a role in inflammation. Mediators Inflamm 2013; 2013:181324. [PMID: 24062611 PMCID: PMC3766570 DOI: 10.1155/2013/181324] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 07/19/2013] [Indexed: 12/13/2022] Open
Abstract
Electronegative low density lipoprotein (LDL(−)) is a minor modified fraction of LDL found in blood. It comprises a heterogeneous population of LDL particles modified by various mechanisms sharing as a common feature increased electronegativity. Modification by oxidation is one of these mechanisms. LDL(−) has inflammatory properties similar to those of oxidized LDL (oxLDL), such as inflammatory cytokine release in leukocytes and endothelial cells. However, in contrast with oxLDL, LDL(−) also has some anti-inflammatory effects on cultured cells. The inflammatory and anti-inflammatory properties ascribed to LDL(−) suggest that it could have a dual biological effect.
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Sánchez-Quesada JL, Estruch M, Benítez S, Ordóñez-Llanos J. Electronegative LDL: a useful biomarker of cardiovascular risk? ACTA ACUST UNITED AC 2012. [DOI: 10.2217/clp.12.26] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Lobo JC, Mafra D, Farage NE, Faulin TDES, Abdalla DSP, de Nóbrega ACL, Torres JPM. Increased electronegative LDL and decreased antibodies against electronegative LDL levels correlate with inflammatory markers and adhesion molecules in hemodialysed patients. Clin Chim Acta 2011; 412:1788-92. [DOI: 10.1016/j.cca.2011.05.034] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 05/31/2011] [Accepted: 05/31/2011] [Indexed: 10/18/2022]
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Urata J, Ikeda S, Koga S, Nakata T, Yasunaga T, Sonoda K, Koide Y, Ashizawa N, Kohno S, Maemura K. Negatively charged low-density lipoprotein is associated with atherogenic risk in hypertensive patients. Heart Vessels 2011; 27:235-42. [PMID: 21491122 DOI: 10.1007/s00380-011-0139-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Accepted: 03/18/2011] [Indexed: 02/02/2023]
Abstract
Negatively charged low-density lipoprotein (LDL), generated via multiple processes such as oxidation, acetylation, or glycosylation, plays a key role in the initiation and progression of atherosclerosis and related diseases. Anion-exchange high-performance liquid chromatography (AE-HPLC) can subfractionate LDL into LDL-1, LDL-2, and LDL-3 based on LDL particle charge, but the clinical significance of LDL subfractions has not yet been elucidated. The aim of this study was to determine the clinical significance of these fractions with particular regard to atherogenic risk in hypertensive patients. Ninety-eight patients with essential hypertension (age 67.0 ± 10.7 years; 54 males) were enrolled in the present study. The relationships between LDL subfractions and atherogenic risk factors, including lipid profiles, blood pressure and plasma 8-isoprostane as a marker of oxidative stress, were examined. LDL-1 levels were significantly and negatively correlated with body mass index (r = -0.384, p < 0.001), systolic blood pressure (r = -0.457, p < 0.001), non-high-density lipoprotein cholesterol levels (r = -0.457, p < 0.001) and 8-isoprostane levels (r = -0.415, p < 0.001). LDL-3, which is the most negatively charged fraction of total LDL, was significantly and positively correlated with these parameters (r = 0.267, 0.481, 0.357, and 0.337, respectively). LDL-1 levels were significantly lower (p < 0.001), and LDL-2 and LDL-3 levels were significantly higher (each p < 0.001) in patients with poorly controlled hypertension than in patients with well-controlled hypertension. In addition, an increase in the total number of traditional risk factors at time of study participation, but not previous diagnosis, was associated with a decrease in LDL-1 levels and increases in LDL-2 and LDL-3 levels. These data suggest that LDL subfractions are associated with multiple atherogenic risk factors and that treatment to modify these risk factors could result in changes in LDL subfraction levels. In conclusion, LDL subfractions isolated by AE-HPLC may represent a marker of atherogenic risk in patients with hypertension.
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Affiliation(s)
- Jungo Urata
- Department of Cardiovascular Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
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12
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Electronegative low-density lipoprotein: Origin and impact on health and disease. Atherosclerosis 2011; 215:257-65. [DOI: 10.1016/j.atherosclerosis.2010.12.028] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 11/25/2010] [Accepted: 12/30/2010] [Indexed: 11/17/2022]
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13
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Ma KW, Dai XZ, Feng SY, Jing AH, Yang JY. Heparinized polyvinyl alcohol to specifically adsorb low-density lipoprotein from plasma. Transfus Apher Sci 2011; 44:3-9. [DOI: 10.1016/j.transci.2010.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Faulin TDES, Cavalcante MF, Abdalla DSP. Role of electronegative LDL and its associated antibodies in the pathogenesis of atherosclerosis. ACTA ACUST UNITED AC 2010. [DOI: 10.2217/clp.10.52] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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15
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Bancells C, Canals F, Benítez S, Colomé N, Julve J, Ordóñez-Llanos J, Sánchez-Quesada JL. Proteomic analysis of electronegative low-density lipoprotein. J Lipid Res 2010; 51:3508-15. [PMID: 20699421 DOI: 10.1194/jlr.m009258] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Low density lipoprotein is a heterogeneous group of lipoproteins that differs in lipid and protein composition. One copy of apolipoprotein (apo)B accounts for over 95% of the LDL protein, but the presence of minor proteins could disturb its biological behavior. Our aim was to study the content of minor proteins in LDL subfractions separated by anion exchange chromatography. Electropositive LDL [LDL(+)] is the native form, whereas electronegative LDL [LDL⁻] is a minor atherogenic fraction present in blood. LC-ESI MS/MS analysis of both LDL fractions identified up to 28 different proteins. Of these, 13 proteins, including apoB, were detected in all the analyzed samples. LDL⁻ showed a higher content of most minor proteins. Statistical analysis of proteomic data indicated that the content of apoE, apoA-I, apoC-III, apoA-II, apoD, apoF, and apoJ was higher in LDL⁻ than in LDL(+). Immunoturbidimetry, ELISA, or Western blot analysis confirmed these differences. ApoJ and apoF presented the highest difference between LDL(+) and LDL⁻ (>15-fold). In summary, the increased content of several apolipoproteins, and specifically of apoF and apoJ, could be related to the physicochemical characteristics of LDL⁻, such as apoB misfolding, aggregation, and abnormal lipid composition.
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Affiliation(s)
- Cristina Bancells
- Servei de Bioquímica, Institut de Recerca, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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Bancells C, Villegas S, Blanco FJ, Benítez S, Gállego I, Beloki L, Pérez-Cuellar M, Ordóñez-Llanos J, Sánchez-Quesada JL. Aggregated electronegative low density lipoprotein in human plasma shows a high tendency toward phospholipolysis and particle fusion. J Biol Chem 2010; 285:32425-35. [PMID: 20670941 DOI: 10.1074/jbc.m110.139691] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Aggregation and fusion of lipoproteins trigger subendothelial retention of cholesterol, promoting atherosclerosis. The tendency of a lipoprotein to form fused particles is considered to be related to its atherogenic potential. We aimed to isolate and characterize aggregated and nonaggregated subfractions of LDL from human plasma, paying special attention to particle fusion mechanisms. Aggregated LDL was almost exclusively found in electronegative LDL (LDL(-)), a minor modified LDL subfraction, but not in native LDL (LDL(+)). The main difference between aggregated (agLDL(-)) and nonaggregated LDL(-) (nagLDL(-)) was a 6-fold increased phospholipase C-like activity in agLDL(-). agLDL(-) promoted the aggregation of LDL(+) and nagLDL(-). Lipoprotein fusion induced by α-chymotrypsin proteolysis was monitored by NMR and visualized by transmission electron microscopy. Particle fusion kinetics was much faster in agLDL(-) than in nagLDL(-) or LDL(+). NMR and chromatographic analysis revealed a rapid and massive phospholipid degradation in agLDL(-) but not in nagLDL(-) or LDL(+). Choline-containing phospholipids were extensively degraded, and ceramide, diacylglycerol, monoacylglycerol, and phosphorylcholine were the main products generated, suggesting the involvement of phospholipase C-like activity. The properties of agLDL(-) suggest that this subfraction plays a major role in atherogenesis by triggering lipoprotein fusion and cholesterol accumulation in the arterial wall.
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Affiliation(s)
- Cristina Bancells
- Departament de Bioquímica, Institut d'Investigacions Biomèdiques Sant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain
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17
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Berthold HK, Mertens J, Birnbaum J, Brämswig S, Sudhop T, Barrett PHR, von Bergmann K, Gouni-Berthold I. Influence of simvastatin on apoB-100 secretion in non-obese subjects with mild hypercholesterolemia. Lipids 2010; 45:491-500. [PMID: 20461472 DOI: 10.1007/s11745-010-3420-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 04/14/2010] [Indexed: 10/19/2022]
Abstract
Statins decrease apoB-100-containing lipoproteins by increasing their fractional catabolic rates through LDL receptor-mediated uptake. Their influence on hepatic secretion of these lipoproteins is controversial. The objective of the study was to examine the influence of simvastatin on the secretion of apoB-100-containing lipoproteins in fasting non-obese subjects. Turnover of apoB-100-containing lipoproteins was investigated using stable isotope-labeled tracers. Multicompartmental modeling was used to derive kinetic parameters. Eight male subjects (BMI 25 +/- 3 kg/m(2)) with mild hypercholesterolemia (LDL cholesterol 135 +/- 30 mg/dL) and normal triglycerides (111 +/- 44 mg/dL) were examined under no treatment (A), under chronic treatment with simvastatin 40 mg/day (B) and after an acute-on-chronic dosage of 80 mg simvastatin under chronic simvastatin treatment (C). Lipoprotein concentrations changed as expected under 40 mg/day simvastatin. Fractional catabolic rates increased in IDL and LDL but not in VLDL fractions versus control [VLDL +35% in B (n.s.) and +21% in C (n.s.); IDL +169% in B (P = 0.08) and +187% in C (P = 0.032); LDL +87% in B (P = 0.025) and +133% in C (P = 0.025)]. Chronic (B) and acute-on-chronic simvastatin treatment (C) did not affect lipoprotein production rates [VLDL -8 and -13%, IDL +47 and +38%, and LDL +19 and +30% in B and C, respectively (all comparisons n.s.)]. The data indicate that simvastatin does not influence the secretion of apoB-100-containing lipoproteins in non-obese subjects with near-normal LDL cholesterol concentrations.
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Affiliation(s)
- Heiner K Berthold
- Department of Clinical Pharmacology, University of Bonn, Bonn, Germany.
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18
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Tremblay AJ, Lamarche B, Hogue JC, Couture P. Effects of ezetimibe and simvastatin on apolipoprotein B metabolism in males with mixed hyperlipidemia. J Lipid Res 2009; 50:1463-71. [PMID: 19305020 PMCID: PMC2694344 DOI: 10.1194/jlr.p800061-jlr200] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2009] [Revised: 02/06/2009] [Indexed: 12/31/2022] Open
Abstract
Sixteen hyperlipidemic men were enrolled in a randomized, placebo-controlled, double-blind, cross-over study to evaluate the effect of ezetimibe 10 mg and simvastatin 40 mg, coadministered and alone, on the in vivo kinetics of apolipoprotein (apo) B-48 and B-100 in humans. Subjects underwent a primed-constant infusion of a stable isotope in the fed state. The coadministration of simvastatin and ezetimibe significantly reduced plasma concentrations of cholesterol (-43.0%), LDL-C (-53.6%), and triglycerides (-44.0%). Triglyceride-rich lipoproteins (TRL) apoB-48 pool size (PS) was significantly decreased (-48.9%) following combination therapy mainly through a significant reduction in TRL apoB-48 production rate (PR) (-38.0%). The fractional catabolic rate (FCR) of VLDL and LDL apoB-100 were significantly increased with all treatment modalities compared with placebo, leading to a significant reduction in the PS of these fractions. We also observed a positive correlation between changes in TRL apoB-48 PS and changes in TRL apoB-48 PR (r = 0.85; P < 0.0001) with combination therapy. Our results indicate that treatment with simvastatin plus ezetimibe is effective in reducing plasma TRL apoB-48 levels and that this effect is most likely mediated by a reduction in the intestinal secretion of TRL apoB-48. Our study also indicated that the reduction in LDL-C concentration following combination therapy is mainly driven by an increase in FCR of apoB-100 containing lipoproteins.
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Affiliation(s)
- André J Tremblay
- Lipid Research Center, CHUL Research Center, Québec City, Québec, Canada
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec City, Québec, Canada
| | - Benoît Lamarche
- Lipid Research Center, CHUL Research Center, Québec City, Québec, Canada
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec City, Québec, Canada
| | - Jean-Charles Hogue
- Lipid Research Center, CHUL Research Center, Québec City, Québec, Canada
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec City, Québec, Canada
| | - Patrick Couture
- Lipid Research Center, CHUL Research Center, Québec City, Québec, Canada
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec City, Québec, Canada
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19
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Santo Faulin TDE, de Sena KCM, Rodrigues Telles AE, de Mattos Grosso D, Bernardi Faulin EJ, Parra Abdalla DS. Validation of a novel ELISA for measurement of electronegative low-density lipoprotein. Clin Chem Lab Med 2009; 46:1769-75. [PMID: 19055454 DOI: 10.1515/cclm.2008.333] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Oxidative modification of low-density lipoprotein (LDL) plays a key role in the pathogenesis of atherosclerosis. LDL(-) is present in blood plasma of healthy subjects and at higher concentrations in diseases with high cardiovascular risk, such as familial hypercholesterolemia or diabetes. METHODS We developed and validated a sandwich ELISA for LDL(-) in human plasma using two monoclonal antibodies against LDL(-) that do not bind to native LDL, extensively copper-oxidized LDL or malondialdehyde-modified LDL. The characteristics of assay performance, such as limits of detection and quantification, accuracy, inter- and intra-assay precision were evaluated. The linearity, interferences and stability tests were also performed. RESULTS The calibration range of the assay is 0.625-20.0 mU/L at 1:2000 sample dilution. ELISA validation showed intra- and inter-assay precision and recovery within the required limits for immunoassays. The limits of detection and quantification were 0.423 mU/L and 0.517 mU/L LDL(-), respectively. The intra- and inter-assay coefficient of variation ranged from 9.5% to 11.5% and from 11.3% to 18.9%, respectively. Recovery of LDL(-) ranged from 92.8% to 105.1%. CONCLUSIONS This ELISA represents a very practical tool for measuring LDL(-) in human blood for widespread research and clinical sample use.
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20
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Mafra D, Santos FR, Lobo JC, de Mattos Grosso D, Barreira AL, Velarde LGC, Abdalla DSP, Leite M. Alpha-tocopherol supplementation decreases electronegative low-density lipoprotein concentration [LDL(-)] in haemodialysis patients. Nephrol Dial Transplant 2009; 24:1587-92. [PMID: 19176686 DOI: 10.1093/ndt/gfn760] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Oxidative stress is a significant contributor to cardiovascular diseases (CVD) in haemodialysis (HD) patients, predisposing to the generation of oxidized low-density lipoprotein (oxLDL) or electronegatively charged LDL subfraction. Antioxidant therapy such as alpha-tocopherol acts as a scavenger of lipid peroxyl radicals attenuating the oxidative stress, which decreases the formation of oxLDL. The present study was designed to investigate the influence of the alpha-tocopherol supplementation on the concentration of electronegative low-density lipoprotein [LDL(-)], a minimally oxidized LDL, which we have previously described to be high in HD patients. METHODS Blood samples were collected before and after 120 days of supplementation by alpha-tocopherol (400 UI/day) in 19 stable HD patients (50 +/- 7.8 years; 9 males). The concentrations of LDL(-) in blood plasma [using an anti-LDL- human monoclonal antibody (mAb)] and the anti-LDL(-) IgG auto-antibodies were determined by ELISA. Calculation of body mass index (BMI) and measurements of waist circumference (WC), triceps skin folds (TSF) and arm muscle area (AMA) were performed. RESULTS The plasma alpha-tocopherol levels increased from 7.9 microM (0.32-18.4) to 14.2 microM (1.22-23.8) after the supplementation (P = 0.02). The mean concentration of LDL(-) was reduced from 570.9 microg/mL (225.6-1241.0) to 169.1 microg/mL (63.6-621.1) (P < 0.001). The anti-LDL(-) IgG auto-antibodies did not change significantly after the supplementation. The alpha-tocopherol supplementation also reduced the total cholesterol and LDL-C levels in these patients, from 176 +/- 42.3 mg/dL to 120 +/- 35.7 mg/dL (P < 0.05) and 115.5 +/- 21.4 mg/dL to 98.5 +/- 23.01 mg/dL (P < 0.001), respectively. CONCLUSION The oral administration of alpha-tocopherol in HD patients resulted in a significant decrease in the LDL(-), total cholesterol and LDL-C levels. This effect may favour a reduction in cardiovascular risk in these patients, but a larger study is required to confirm an effect in this clinical setting.
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Affiliation(s)
- Denise Mafra
- Department of Clinical Nutrition, Federal Fluminense University (UFF), Niterói, Brazil.
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21
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Zhang B, Matsunaga A, Rainwater DL, Miura SI, Noda K, Nishikawa H, Uehara Y, Shirai K, Ogawa M, Saku K. Effects of rosuvastatin on electronegative LDL as characterized by capillary isotachophoresis: the ROSARY Study. J Lipid Res 2008; 50:1832-41. [PMID: 19056704 DOI: 10.1194/jlr.m800523-jlr200] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP.
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Affiliation(s)
- Bo Zhang
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka 814-0180, Japan
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22
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Grosso D, Ferderbar S, Wanschel A, Krieger M, Higushi M, Abdalla D. Antibodies against electronegative LDL inhibit atherosclerosis in LDLr-/- mice. Braz J Med Biol Res 2008; 41:1086-92. [DOI: 10.1590/s0100-879x2008001200007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Accepted: 12/08/2008] [Indexed: 11/21/2022] Open
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23
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Ma KW, Ma L, Cai SX, Wang X, Liu B, Xu ZL, Dai XZ, Yang JY, Jing AH, Lei WJ. Preparation of heparin-immobilized PVA and its adsorption for low-density lipoprotein from hyperlipemia plasma. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2008; 19:3255-3261. [PMID: 18470702 DOI: 10.1007/s10856-008-3461-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Accepted: 04/17/2008] [Indexed: 05/26/2023]
Abstract
In this study, heparin was covalently coupled by glutaraldehyde to Poly(vinyl alcohol) [PVA] in solid-liquid two-phase reaction system by two-step synthesis method to prepare a LDL-selective adsorbent. The parameters (the material ratio, reaction time and dosage of catalyzer) were investigated to evaluate their effect upon the immobilized amount of heparin onto the surface of PVA, IR was used to verify the covalent immobilization result and the heparin-modified PVA was also undergone the evaluation of its adsorption capability for low-density lipoprotein from hyperlipemia plasma, and its hemocompatibility was preliminarily evaluated by platelet adhesion test. Results showed: (1) under optimized reaction conditions the highest immobilization amount of heparin onto PVA surface within the experiments of this study has been obtained; (2) the optimized reaction conditions were: (i) at the refluxing temperature 78 degrees C; (ii) the material ratio of "PVA(g): 50% glutaraldehyde (ml)" was about "1:3"; (iii) the reaction time was about 5 h; and (iv) the amount of catalyzer (concentrated HCL) was about 1% of the 50% glutaraldehyde; (3) within the experiments of this study the highest immobilization amount would be up to 25 microg heparin on the surface of per g PVA granules; (4) the heparin-modified PVA granules showed significant adsorption for LDL under faintly alkaline environment (pH=7.2-9.5) ; (5) The result of platelet adhesion test showed no platelet adhered to its surface. Therefore, immobilization of heparin onto the surface of a support is one approach to prepare a kind of LDL adsorbent for blood purification.
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Affiliation(s)
- Kai-Wang Ma
- College of Medical Technology & Engineering, Henan University of Science and Technology, Luoyang 471003, People's Republic of China.
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24
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Zhang B, Miura SI, Yanagi D, Noda K, Nishikawa H, Matsunaga A, Shirai K, Iwata A, Yoshinaga K, Adachi H, Imaizumi T, Saku K. Reduction of charge-modified LDL by statin therapy in patients with CHD or CHD risk factors and elevated LDL-C levels: the SPECIAL Study. Atherosclerosis 2008; 201:353-9. [PMID: 18395728 DOI: 10.1016/j.atherosclerosis.2008.02.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 02/04/2008] [Accepted: 02/10/2008] [Indexed: 10/22/2022]
Abstract
Various forms of atherogenic modified low-density lipoprotein (LDL) including oxidized LDL and small, dense LDL have increased negative charge as compared to normal LDL. Charge-modified LDL (electronegative LDL) and normal LDL subfractions in plasma are analyzed by capillary isotachophoresis (cITP) as fast-migrating LDL (fLDL) and slow-migrating LDL (sLDL). We examined the effects of pravastatin and simvastatin on charge-based LDL subfractions as determined by cITP in patients with hypercholesterolemia. Patients (n=72) with CHD or CHD risk factors and elevated LDL cholesterol (LDL-C) levels were randomly assigned to receive pravastatin or simvastatin. After treatment with statins for 3 and 6 months, both cITP fLDL and sLDL were reduced (p<0.05) from the baseline, but the effects did not differ between treatment with pravastatin and simvastatin. At baseline and after treatment for 3 months, cITP sLDL was correlated with LDL-C, but fLDL was correlated with inflammatory markers, high-sensitive C-reactive protein and LDL-associated platelet-activating factor acetylhydrolase, and atherogenic lipoproteins, remnant-like particle cholesterol and small, dense LDL cholesterol. In conclusion, cITP fLDL was related to inflammatory markers and atherogenic lipoproteins and was reduced by treatment with statins. Charge-modified LDL subfraction could be a potential marker for atherosclerosis and a target for therapy.
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Affiliation(s)
- Bo Zhang
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan.
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25
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Lamon-Fava S, Diffenderfer MR, Barrett PHR, Buchsbaum A, Matthan NR, Lichtenstein AH, Dolnikowski GG, Horvath K, Asztalos BF, Zago V, Schaefer EJ. Effects of different doses of atorvastatin on human apolipoprotein B-100, B-48, and A-I metabolism. J Lipid Res 2007; 48:1746-53. [PMID: 17526934 DOI: 10.1194/jlr.m700067-jlr200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Nine hypercholesterolemic and hypertriglyceridemic subjects were enrolled in a randomized, placebo-controlled, double-blind, crossover study to test the effect of atorvastatin 20 mg/day and 80 mg/day on the kinetics of apolipoprotein B-100 (apoB-100) in triglyceride-rich lipoprotein (TRL), intermediate density lipoprotein (IDL), and LDL, of apoB-48 in TRL, and of apoA-I in HDL. Compared with placebo, atorvastatin 20 mg/day was associated with significant reductions in TRL, IDL, and LDL apoB-100 pool size as a result of significant increases in fractional catabolic rate (FCR) without changes in production rate (PR). Compared with the 20 mg/day dose, atorvastatin 80 mg/day caused a further significant reduction in the LDL apoB-100 pool size as a result of a further increase in FCR. ApoB-48 pool size was reduced significantly by both atorvastatin doses, and this reduction was associated with nonsignificant increases in FCR. The lathosterol-campesterol ratio was decreased by atorvastatin treatment, and changes in this ratio were inversely correlated with changes in TRL apoB-100 and apoB-48 PR. No significant effect on apoA-I kinetics was observed at either dose of atorvastatin. Our data indicate that atorvastatin reduces apoB-100- and apoB-48-containing lipoproteins by increasing their catabolism and has a dose-dependent effect on LDL apoB-100 kinetics. Atorvastatin-mediated changes in cholesterol homeostasis may contribute to apoB PR regulation.
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Affiliation(s)
- Stefania Lamon-Fava
- Lipid Metabolism Laboratory, Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
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26
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Benítez S, Pérez A, Sánchez-Quesada JL, Wagner AM, Rigla M, Arcelus R, Jorba O, Ordóñez-Llanos J. Electronegative low-density lipoprotein subfraction from type 2 diabetic subjects is proatherogenic and unrelated to glycemic control. Diabetes Metab Res Rev 2007; 23:26-34. [PMID: 16634114 DOI: 10.1002/dmrr.643] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND The physicochemical and biological characteristics of electronegative low-density lipoprotein (LDL) (LDL(-)) from type 2 diabetic patients (DM2), before and after insulin therapy, were studied. METHODS Total LDL was subfractionated in LDL(+) (native LDL) and LDL(-) by anion-exchange chromatography. RESULTS The proportion of LDL(-) was increased in plasma from DM2 patients compared to control subjects (13.8 +/- 4.6% versus 6.1 +/- 2.5, P < 0.05) and was not modified after glycemic optimization (14.0 +/- 5.9%). LDL(-) from DM2 patients presented similar differential characteristics versus LDL(+) than LDL(-) from controls; that is, decreased apoB and oxidizability, and increased triglyceride, nonesterified fatty acids (NEFA), apoE, apoC-III, platelet-activating factor (PAF) acetylhydrolase activity and aggregability. No difference in particle size, antioxidants, malondialdehyde (MDA), fructosamine or glycated low-density lipoprotein (gLDL) was observed between LDL subfractions. Concerning differences between LDL subfractions isolated from DM2 and from control subjects, the former showed increased MDA, fructosamine and gLDL proportion and decreased LDL size and antioxidant content. The only effect of glycemic optimization was a decrease in fructosamine and gLDL in LDL(+) from DM2 subjects. LDL(-) from DM2 patients presented low binding affinity to the low-density lipoprotein receptor (LDLr) in cultured fibroblasts compared to LDL(+) and two- to threefold increased ability to release interleukin-8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) in endothelial cells. CONCLUSION These results suggest that, although nonenzymatic glycosylation and oxidation are increased in type 2 diabetes, these features would not be directly involved in the generation of LDL(-). Moreover, LDL(-) properties suggest that the high proportion observed in plasma could promote accelerated atherosclerosis in DM2 patients through increased residence time in plasma and induction of inflammatory responses in artery wall cells.
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Affiliation(s)
- Sónia Benítez
- Research Institute, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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27
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Chen HH, Hosken BD, Huang M, Gaubatz JW, Myers CL, Macfarlane RD, Pownall HJ, Yang CY. Electronegative LDLs from familial hypercholesterolemic patients are physicochemically heterogeneous but uniformly proapoptotic. J Lipid Res 2007; 48:177-84. [PMID: 17015886 DOI: 10.1194/jlr.m500481-jlr200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A highly electronegative fraction of human plasma LDLs, designated L5, has distinctive biological activity that includes induction of apoptosis in bovine aortic endothelial cells (BAECs). This study was performed to identify a relationship between LDL density, electronegativity, and biological activity, namely, the induction of apoptosis in BAECs. Plasma LDLs from normolipidemic subjects and homozygotic familial hypercholesterolemia subjects were separated into five subfractions, with increasing electronegativity from L1 to L5, and into seven subfractions according to increasing density, D1 to D7. L1 to L5 were also separated according to density, and D1 to D7 were separated according to charge. The density profiles of L1 to L5 were similar (maximum density = 1.030 +/- 0.002 g/ml). Induction of apoptosis by all seven density subfractions was confined to the highly electronegative fraction, L5, and within each density subfraction the magnitude of apoptosis correlated with the L5 content. Electronegative LDL is heterogeneous with respect to density and composition, and induction of apoptosis is more strongly associated with LDL electronegativity than with LDL size or density.
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Affiliation(s)
- Hsin-hung Chen
- Section of Atherosclerosis and Lipoprotein Research, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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28
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Gloerich J, van den Brink DM, Ruiter JPN, van Vlies N, Vaz FM, Wanders RJA, Ferdinandusse S. Metabolism of phytol to phytanic acid in the mouse, and the role of PPARα in its regulation. J Lipid Res 2007; 48:77-85. [PMID: 17015885 DOI: 10.1194/jlr.m600050-jlr200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phytol, a branched-chain fatty alcohol, is the naturally occurring precursor of phytanic and pristanic acid, branched-chain fatty acids that are both ligands for the nuclear hormone receptor peroxisome proliferator-activated receptor alpha (PPARalpha). To investigate the metabolism of phytol and the role of PPARalpha in its regulation, wild-type and PPARalpha knockout (PPARalpha-/-) mice were fed a phytol-enriched diet or, for comparison, a diet enriched with Wy-14,643, a synthetic PPARalpha agonist. After the phytol-enriched diet, phytol could only be detected in small intestine, the site of uptake, and liver. Upon longer duration of the diet, the level of the (E)-isomer of phytol increased significantly in the liver of PPARalpha-/- mice compared with wild-type mice. Activity measurements of the enzymes involved in phytol metabolism showed that treatment with a PPARalpha agonist resulted in a PPARalpha-dependent induction of at least two steps of the phytol degradation pathway in liver. Furthermore, the enzymes involved showed a higher activity toward the (E)-isomer than the (Z)-isomer of their respective substrates, indicating a stereospecificity toward the metabolism of (E)-phytol. In conclusion, the results described here show that the conversion of phytol to phytanic acid is regulated via PPARalpha and is specific for the breakdown of (E)-phytol.
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Affiliation(s)
- J Gloerich
- Laboratory of Genetic Metabolic Diseases, Department of Clinical Chemistry, Emma's Children's Hospital, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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29
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Benítez S, Camacho M, Bancells C, Vila L, Sánchez-Quesada JL, Ordóñez-Llanos J. Wide proinflammatory effect of electronegative low-density lipoprotein on human endothelial cells assayed by a protein array. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1014-21. [PMID: 16753331 DOI: 10.1016/j.bbalip.2006.03.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 03/17/2006] [Accepted: 03/27/2006] [Indexed: 02/08/2023]
Abstract
Electronegative low-density lipoprotein (LDL(-)) is a modified subfraction of LDL present in plasma able to induce the release of interleukin 8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) by human umbilical vein endothelial cells (HUVEC). To ascertain whether further inflammation mediator release could be induced by LDL(-), a protein array system was used to measure 42 cytokines and related compounds. Native LDL and LDL(-) isolated from normolipemic subjects were incubated for 24 h with HUVEC and culture supernatants were used to measure inflammation mediator release. The protein array revealed that IL-6, granulocyte/monocyte colony-stimulating factor (GM-CSF) and growth-related oncogene (GRO) release were increased by cultured HUVEC in response to LDL(-). LDL(-) enhanced production of IL-6 (4-fold vs. LDL(+)), GM-CSF (4-fold), GRObeta (2-fold) and GROgamma (7-fold) was confirmed by ELISA. Time-course experiments revealed that IL-6 was released earlier than the other inflammation mediators, suggesting a first-wave cytokine action. However, the addition of IL-6 alone did not stimulate the production of IL-8, MCP-1 or GM-CSF. Moreover, IL-8, MCP-1 or GM-CSF alone did not promote the release of the other inflammatory molecules. Modification of LDL(+) by phospholipase A(2)-mediated lipolysis or by loading with non-esterified fatty acids (NEFA) reproduced the action of LDL(-), thereby suggesting the involvement of NEFA and/or lysophosphatidylcholine in the release of these molecules. Our results indicate that LDL(-) promotes a proinflammatory phenotype in endothelial cells through the production of cytokines, chemokines and growth factors.
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Affiliation(s)
- Sònia Benítez
- Department of Biochemistry and Institut de Recerca, Hospital de la Santa Creu i Sant Pau, C/Antoni Maria Claret 167, 08025 Barcelona, Spain
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Sánchez-Quesada JL, Benítez S, Pérez A, Wagner AM, Rigla M, Carreras G, Vila L, Camacho M, Arcelus R, Ordóñez-Llanos J. The inflammatory properties of electronegative low-density lipoprotein from type 1 diabetic patients are related to increased platelet-activating factor acetylhydrolase activity. Diabetologia 2005; 48:2162-9. [PMID: 16132957 DOI: 10.1007/s00125-005-1899-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2005] [Accepted: 05/31/2005] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Chemical and biological characteristics of LDL(-) from type 1 diabetic subjects were analysed. The diabetic patients were studied during poor and optimised glycaemic control. MATERIALS AND METHODS Total LDL was subfractionated into electropositive LDL(+) and electronegative LDL(-) by anion exchange chromatography and the lipid and protein composition of the two determined. RESULTS LDL(-) differed from LDL(+) in that it had higher triglyceride, non-esterified fatty acids, apoE, apoC-III and platelet-activating factor acetylhydrolase (PAF-AH), as well as lower apoB relative content. No evidence of increased oxidation was observed in LDL(-). LDL(-) increased two-fold the release of interleukin 8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) in endothelial cells, suggesting an inflammatory role. Optimisation of glycaemic control after insulin therapy decreased the proportion of LDL(-), but did not modify the composition of LDL subfractions, except for a decrease in PAF-AH activity in LDL(-). The possibility that LDL(-) could be generated by non-enzymatic glycosylation was studied. Fructosamine and glycated LDL content in LDL subfractions from type 1 diabetic patients was greater than in LDL subfractions isolated from normoglycaemic subjects, and decreased after glycaemic optimisation in both subfractions. However, no difference was observed between LDL(+) and LDL(-) before and after insulin therapy. CONCLUSIONS/INTERPRETATION These results provide evidence that LDL(-) is not produced by glycosylation. Nevertheless, LDL(-) from diabetic patients displays inflammatory potential reflected by the induction of chemokine release in endothelial cells. This proatherogenic effect could be related to the high PAF-AH activity in LDL(-).
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Affiliation(s)
- J L Sánchez-Quesada
- Department of Biochemistry, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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Alonso R, Mata N, Mata P. Benefits and risks assessment of simvastatin in familial hypercholesterolaemia. Expert Opin Drug Saf 2005; 4:171-81. [PMID: 15794711 DOI: 10.1517/14740338.4.2.171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Familial hypercholesterolaemia (FH) is a frequent inherited monogenic disorder, associated with premature coronary artery disease. Life expectancy of FH patients is reduced by 15 - 30 years unless they are adequately treated with lipid-lowering therapy. Patients with this disorder need long-term drug therapy and the selection of treatment should be strongly based on its long-term safety and tolerability. The introduction of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors has changed the treatment of FH. Simvastatin 40 - 80 mg/day effectively reduces serum low-density lipoprotein cholesterol levels, and also reduces triglycerides with a modest rise in high-density lipoprotein cholesterol levels. Other potentially important effects, such as improvement of endothelial function, reduction of LDL oxidation and vascular inflammation, have been associated with simvastatin therapy in FH. In addition, simvastatin has been shown to abolish the progression, and even facilitate the regression of existing human atherosclerotic lesions. The safety and tolerability of simvastatin is clearly highlighted by the low rate of therapy discontinuation observed in several population-based clinical trials. Asymptomatic elevations in liver transaminase levels and myopathy are uncommon. The efficacy and tolerability of simvastatin at doses up to 80 mg/day are well-established, as well as its cost-effectiveness in the management of FH patients.
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Affiliation(s)
- Rodrigo Alonso
- Fundación Jiménez Díaz, Lipid Clinic, Internal Medicine Department, Madrid 28040, Spain
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Benítez S, Camacho M, Arcelus R, Vila L, Bancells C, Ordóñez-Llanos J, Sánchez-Quesada JL. Increased lysophosphatidylcholine and non-esterified fatty acid content in LDL induces chemokine release in endothelial cells. Relationship with electronegative LDL. Atherosclerosis 2005; 177:299-305. [PMID: 15530903 DOI: 10.1016/j.atherosclerosis.2004.07.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2004] [Revised: 06/17/2004] [Accepted: 07/22/2004] [Indexed: 10/26/2022]
Abstract
Electronegative low-density lipoprotein (LDL(-)) is a plasma-circulating LDL subfraction with proinflammatory properties that induces the production of chemokines in cultured endothelial cells. However, the specific mechanism of LDL(-)-mediated chemokine release is presently unknown. A characteristic feature of LDL(-) is an increased content of lysophosphatidylcholine (LPC) and non-esterified fatty acids (NEFA). The effect of increasing amounts of LPC and NEFA associated with LDL on the release of chemokines by endothelial cells was studied. Total LDL was subfractionated by anion-exchange chromatography in electropositive (LDL(+)) and LDL(-). LDL(-) contained two-fold more LPC and NEFA than LDL(+) and induced two- to four-fold more (p < 0.05) interleukin-8 (IL-8, 11.5 +/- 8.2 ng/10(5) cells) and monocyte chemotactic protein-1 (MCP-1, 10.8 +/- 3.8 ng/10(5) cells) release by human umbilical vein endothelial cells (HUVEC) than LDL(+) (IL-8: 3.4 +/- 1.5 ng/10(5) cells, MCP-1: 5.8 +/- 2.9 ng/10(5) cells). The content of LPC and NEFA in LDL(+) was increased by enzymatic treatment with secretory phospholipase A(2) (sPLA(2)) at 5 ng/mL or 20 ng/mL or by incubation with NEFA at 2 mmol/L. Modification of LDL(+) by both methods did not result in oxidative modification as demonstrated by the lack of change in antioxidants, conjugated dienes and malondialdehyde content. sPLA(2) treatment resulted in an increase in LPC and NEFA in LDL(+) which enhanced its ability to release IL-8 and MCP-1 by HUVEC in a concentration-dependent manner (sPLA(2)(5)-LDL; IL-8: 7.1 +/- 3.8ng/10(5) cells, MCP-1: 8.0 +/- 5.1 ng/10(5) cells; sPLA(2)(20)-LDL; IL-8: 20.8 +/- 11.2 ng/10(5) cells, MCP-1: 15.0 +/- 7.5 ng/10(5) cells). NEFA loading of LDL(+) also favored the release of IL-8 and MCP-1 (IL-8: 7.8 +/- 6.1 ng/10(5) cells, MCP-1: 8.4 +/- 2.7 ng/10(5) cells, p < 0.05 versus LDL(+)). These effects were observed when modified LDL(+) reached a content of LPC and/or NEFA similar that of LDL(-). These data indicate that non-oxidized polar lipids associated with LDL promote an inflammatory response in endothelial cells and suggest that increased NEFA and LPC could be involved in the inflammatory activity of LDL(-).
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Affiliation(s)
- Sònia Benítez
- Department of Biochemistry and Inflammation Mediators Laboratory, Institut de Recerca, Hospital de la Santa Creu i Sant Pau, C/ Antoni Maria Claret 167, Barcelona 08025, Spain
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Benítez S, Villegas V, Bancells C, Jorba O, González-Sastre F, Ordóñez-Llanos J, Sánchez-Quesada JL. Impaired Binding Affinity of Electronegative Low-Density Lipoprotein (LDL) to the LDL Receptor Is Related to Nonesterified Fatty Acids and Lysophosphatidylcholine Content†. Biochemistry 2004; 43:15863-72. [PMID: 15595841 DOI: 10.1021/bi048825z] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The binding characteristics of electropositive [LDL(+)] and electronegative LDL [LDL(-)] subfractions to the LDL receptor (LDLr) were studied. Saturation kinetic studies in cultured human fibroblasts demonstrated that LDL(-) from normolipemic (NL) and familial hypercholesterolemic (FH) subjects had lower binding affinity than their respective LDL(+) fractions (P < 0.05), as indicated by higher dissociation constant (K(D)) values. FH-LDL(+) also showed lower binding affinity (P < 0.05) than NL-LDL(+) (K(D), sorted from lower to higher affinity: NL-LDL(-), 33.0 +/- 24.4 nM; FH-LDL(-), 24.4 +/- 7.1 nM; FH-LDL(+), 16.6 +/- 7.0 nM; NL-LDL(+), 10.9 +/- 5.7 nM). These results were confirmed by binding displacement studies. The impaired affinity binding of LDL(-) could be attributed to altered secondary and tertiary structure of apolipoprotein B, but circular dichroism (CD) and tryptophan fluorescence (TrpF) studies revealed no structural differences between LDL(+) and LDL(-). To ascertain the role of increased nonesterified fatty acids (NEFA) and lysophosphatidylcholine (LPC) content in LDL(-), LDL(+) was enriched in NEFA or hydrolyzed with secretory phospholipase A(2). Modification of LDL gradually decreased the affinity to LDLr in parallel to the increasing content of NEFA and/or LPC. Modified LDLs with a NEFA content similar to that of LDL(-) displayed similar affinity. ApoB structure studies of modified LDLs by CD and TrpF showed no difference compared to LDL(+) or LDL(-). Our results indicate that NEFA loading or phospholipase A(2) lipolysis of LDL leads to changes that affect the affinity of LDL to LDLr with no major effect on apoB structure. Impaired affinity to the LDLr shown by LDL(-) is related to NEFA and/or LPC content rather than to structural differences in apolipoprotein B.
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Affiliation(s)
- Sonia Benítez
- Institut de Recerca, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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Abstract
PURPOSE OF REVIEW The occurrence in blood of an electronegatively charged LDL was described in 1988. During the 1990s reports studying electronegative LDL (LDL(-)) were scant and its atherogenic role controversial. Nevertheless, recent reports have provided new evidence on a putative atherogenic role of LDL(-). This review focuses on and discusses these new findings. RECENT FINDINGS In recent years, LDL(-) has been found to be involved in several atherogenic features through its action on cultured endothelial cells. LDL(-) induces the production of chemokines, such as IL-8 and monocyte chemotactic protein 1, and increases tumor necrosis factor-alpha-induced production of vascular cell adhesion molecule 1, with these molecules being involved in early phases of leukocyte recruitment. LDL(-) from familial hypercholesterolemic patients also decreases DNA synthesis and intracellular fibroblast growth factor 2 production, which may contribute to impaired angiogenesis and increased apoptosis. In addition, the preferential association of platelet-activating factor acetylhydrolase with LDL(-) has been reported, suggesting a proinflammatory role of this enzyme in LDL(-). SUMMARY Recent findings suggest that LDL(-) could contribute to atherogenesis via several mechanisms, including proinflammatory, proapoptotic and anti-angiogenesis properties. Further studies are required to define the role of LDL(-) in atherogenesis more precisely and to clarify mechanisms involved in endothelial cell activation.
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Affiliation(s)
- José Luis Sánchez-Quesada
- Biochemistry Department and Research Institute, Hospital de la Santa Creu i Sant Pau, C/Antoni Maria Claret 167, 08025 Barcelona, Spain
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