1
|
Montasser ME, Van Hout CV, Miloscio L, Howard AD, Rosenberg A, Callaway M, Shen B, Li N, Locke AE, Verweij N, De T, Ferreira MA, Lotta LA, Baras A, Daly TJ, Hartford SA, Lin W, Mao Y, Ye B, White D, Gong G, Perry JA, Ryan KA, Fang Q, Tzoneva G, Pefanis E, Hunt C, Tang Y, Lee L, Sztalryd-Woodle C, Mitchell BD, Healy M, Streeten EA, Taylor SI, O'Connell JR, Economides AN, Della Gatta G, Shuldiner AR. Genetic and functional evidence links a missense variant in B4GALT1 to lower LDL and fibrinogen. Science 2021; 374:1221-1227. [PMID: 34855475 DOI: 10.1126/science.abe0348] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- May E Montasser
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Cristopher V Van Hout
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA.,Laboratorio Internacional de Investigatión sobre el Genoma Humano, Campus Juriquilla de la Universidad Nacional Autónoma de México, Querétaro, Querétaro 76230, México
| | | | - Alicia D Howard
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD 20993, USA
| | | | | | - Biao Shen
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Ning Li
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Adam E Locke
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | - Niek Verweij
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | - Tanima De
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | | | - Luca A Lotta
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | - Aris Baras
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | - Thomas J Daly
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | | | - Wei Lin
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Yuan Mao
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Bin Ye
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | - Derek White
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Guochun Gong
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - James A Perry
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Kathleen A Ryan
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Qing Fang
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Gannie Tzoneva
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA
| | | | - Charleen Hunt
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Yajun Tang
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Lynn Lee
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | | | - Carole Sztalryd-Woodle
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,US Department of Veterans Affairs, Washington, DC 20420 USA
| | - Braxton D Mitchell
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,Geriatrics Research and Education Clinical Center, VA Medical Center, Baltimore, MD 21201, USA
| | | | - Elizabeth A Streeten
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,Division of Genetics, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Simeon I Taylor
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Jeffrey R O'Connell
- Division of Endocrinology, Diabetes and Nutrition and Program for Personalized and Genomic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Aris N Economides
- Regeneron Genetics Center, LLC, Tarrytown, NY 10591, USA.,Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | | | | |
Collapse
|
2
|
Aguilar Díaz de león JS, Glenn HL, Knappenberger M, Borges CR. Oxidized-Desialylated Low-Density Lipoprotein Inhibits the Antitumor Functions of Lymphokine Activated Killer Cells. J Cancer 2021; 12:4993-5004. [PMID: 34234868 PMCID: PMC8247392 DOI: 10.7150/jca.55526] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/19/2021] [Indexed: 11/09/2022] Open
Abstract
Elevated concentrations of circulating low density lipoprotein (LDL) that is abnormally oxidized and desialylated is both a precursor to and a hallmark of atherosclerosis. Peripheral blood mononuclear cells (PBMCs) treated in vitro with interleukin-2 (IL-2) become lymphokine activated killer (LAK) cells, the primary effectors of which are NK cells and NKT cells. LAK cells display antitumor functions such as increased cytotoxicity and IFN-γ production, and they have been evaluated as a potential cancer therapeutic. Atherosclerotic processes may influence innate immunity against cancer. Because prior studies have shown that low density lipoprotein (LDL) reduces T-cell and NK cell antitumor functions, we asked whether oxidized-desialylated LDL affects the functionality of LAK cells in vitro. We show here that LAK cells take up oxidized-desialylated LDL to a significantly greater extent than native LDL over a period of 72 hours. This resulted in a significant downregulation of LAK cell cytotoxicity against K562 cells. In particular, the expression of IFN-γ, CD56, and NKG2D were reduced upon oxidized-desialylated LDL treatment of LAK cells and, conversely, their expression was enhanced with native LDL. It was also observed that as the number of CD56 and NKG2D positive cells decreased upon treatment with oxidized-desialylated LDL, the number of CD3 positive cells increased in proportion. Additionally, only a slight inhibition of LAK cell cytotoxicity was observed with desialylation alone of LDL, and no significant inhibition was observed with oxidation alone of LDL. Thus, this study describes a new role of oxidized-desialylated LDL as an inhibitor of the antitumor functions of LAK cells. These observations have implications for how atherosclerosis processes, namely oxidation and desialylation of LDL, may influence LAK cell antitumor activity.
Collapse
Affiliation(s)
- Jesús S Aguilar Díaz de león
- School of Molecular Sciences and The Biodesign Institute - Center for Personalized Diagnostics, Arizona State University, P.O. Box 876401, Tempe, AZ 85287, USA
| | - Honor L Glenn
- School of Life Sciences and The Biodesign Institute - Center for Immunotherapy, Vaccines and Virotherapy, Tempe, AZ 85287, USA
| | - Mark Knappenberger
- School of Life Sciences and The Biodesign Institute - Center for Personalized Diagnostics, Arizona State University, P.O. Box 876401, Tempe, AZ 85287, USA
| | - Chad R Borges
- School of Molecular Sciences and The Biodesign Institute - Center for Personalized Diagnostics, Arizona State University, P.O. Box 876401, Tempe, AZ 85287, USA
| |
Collapse
|
3
|
Bocquet O, Wahart A, Sarazin T, Vincent E, Schneider C, Fougerat A, Gayral S, Henry A, Blaise S, Romier-Crouzet B, Boulagnon C, Jaisson S, Gillery P, Bennasroune A, Sartelet H, Laffargue M, Martiny L, Duca L, Maurice P. Adverse Effects of Oseltamivir Phosphate Therapy on the Liver of LDLR-/- Mice Without Any Benefit on Atherosclerosis and Thrombosis. J Cardiovasc Pharmacol 2021; 77:660-672. [PMID: 33760798 DOI: 10.1097/fjc.0000000000001002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/10/2021] [Indexed: 02/06/2023]
Abstract
ABSTRACT Desialylation, governed by sialidases or neuraminidases, is strongly implicated in a wide range of human disorders, and accumulative data show that inhibition of neuraminidases, such as neuraminidases 1 sialidase, may be useful for managing atherosclerosis. Several studies have reported promising effects of oseltamivir phosphate, a widely used anti-influenza sialidase inhibitor, on human cancer cells, inflammation, and insulin resistance. In this study, we evaluated the effects of oseltamivir phosphate on atherosclerosis and thrombosis and potential liver toxicity in LDLR-/- mice fed with high-fat diet. Our results showed that oseltamivir phosphate significantly decreased plasma levels of LDL cholesterol and elastin fragmentation in aorta. However, no effect was observed on both atherosclerotic plaque size in aortic roots and chemically induced thrombosis in carotid arteries. Importantly, oseltamivir phosphate administration had adverse effects on the liver of mice and significantly increased messenger RNA expression levels of F4/80, interleukin-1β, transforming growth factor-β1, matrix metalloproteinase-12, and collagen. Taken together, our findings suggest that oseltamivir phosphate has limited benefits on atherosclerosis and carotid thrombosis and may lead to adverse side effects on the liver with increased inflammation and fibrosis.
Collapse
Affiliation(s)
- Olivier Bocquet
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Amandine Wahart
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Thomas Sarazin
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Elise Vincent
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Christophe Schneider
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Anne Fougerat
- INSERM UMR1048 I2MC, Université Paul Sabatier, Toulouse, France
| | | | - Aubéri Henry
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Sébastien Blaise
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Béatrice Romier-Crouzet
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Camille Boulagnon
- Laboratoire d'anatomie et de Cytologie Pathologique, Hôpital Robert Debré, CHU de Reims; and
| | - Stéphane Jaisson
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
- Department of Biochemistry-Pharmacology-Toxicology, University Hospital of Reims, Reims, France
| | - Philippe Gillery
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
- Department of Biochemistry-Pharmacology-Toxicology, University Hospital of Reims, Reims, France
| | - Amar Bennasroune
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Hervé Sartelet
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | | | - Laurent Martiny
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Laurent Duca
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| | - Pascal Maurice
- UMR CNRS 7369 Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne (URCA), UFR Sciences Exactes et Naturelles, Reims, France
| |
Collapse
|
4
|
White EJ, Gyulay G, Lhoták Š, Szewczyk MM, Chong T, Fuller MT, Dadoo O, Fox-Robichaud AE, Austin RC, Trigatti BL, Igdoura SA. Sialidase down-regulation reduces non-HDL cholesterol, inhibits leukocyte transmigration, and attenuates atherosclerosis in ApoE knockout mice. J Biol Chem 2018; 293:14689-14706. [PMID: 30097518 DOI: 10.1074/jbc.ra118.004589] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/01/2018] [Indexed: 01/01/2023] Open
Abstract
Atherosclerosis is a complex disease that involves alterations in lipoprotein metabolism and inflammation. Protein and lipid glycosylation events, such as sialylation, contribute to the development of atherosclerosis and are regulated by specific glycosidases, including sialidases. To evaluate the effect of the sialidase neuraminidase 1 (NEU1) on atherogenesis, here we generated apolipoprotein E (ApoE)-deficient mice that express hypomorphic levels of NEU1 (Neu1hypoApoe-/-). We found that the hypomorphic NEU1 expression in male Apoe-/- mice reduces serum levels of very-low-density lipoprotein (VLDL) and LDL cholesterol, diminishes infiltration of inflammatory cells into lesions, and decreases aortic sinus atherosclerosis. Transplantation of Apoe-/- bone marrow (BM) into Neu1hypoApoe-/- mice significantly increased atherosclerotic lesion development and had no effect on serum lipoprotein levels. Moreover, Neu1hypoApoe-/- mice exhibited a reduction in circulating monocyte and neutrophil levels and had reduced hyaluronic acid and P-selectin adhesion capability on monocytes/neutrophils and T cells. Consistent with these findings, administration of a sialidase inhibitor, 2-deoxy-2,3-dehydro-N-acetylneuraminic acid, had a significant anti-atherogenic effect in the Apoe-/- mice. In summary, the reduction in NEU1 expression or function decreases atherosclerosis in mice via its significant effects on lipid metabolism and inflammatory processes. We conclude that NEU1 may represent a promising target for managing atherosclerosis.
Collapse
Affiliation(s)
| | | | - Šárka Lhoták
- the Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare and Hamilton Centre for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | | | | | - Mark T Fuller
- Biochemistry and Biomedical Sciences.,Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario L8S 4K1 and
| | - Omid Dadoo
- Biochemistry and Biomedical Sciences.,Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario L8S 4K1 and
| | - Alison E Fox-Robichaud
- the Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare and Hamilton Centre for Kidney Research, Hamilton, Ontario L8N 4A6, Canada.,Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario L8S 4K1 and
| | - Richard C Austin
- the Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare and Hamilton Centre for Kidney Research, Hamilton, Ontario L8N 4A6, Canada.,Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario L8S 4K1 and
| | - Bernardo L Trigatti
- Biochemistry and Biomedical Sciences.,Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario L8S 4K1 and
| | - Suleiman A Igdoura
- From the Departments of Biology, .,Pathology and Molecular Medicine, and
| |
Collapse
|
5
|
Krishnan S, Huang J, Lee H, Guerrero A, Berglund L, Anuurad E, Lebrilla CB, Zivkovic AM. Combined High-Density Lipoprotein Proteomic and Glycomic Profiles in Patients at Risk for Coronary Artery Disease. J Proteome Res 2015; 14:5109-18. [DOI: 10.1021/acs.jproteome.5b00730] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | - Lars Berglund
- Department
of Veterans Affairs, Northern California Health Care System, Sacramento, California 95655, United States
| | | | | | | |
Collapse
|
6
|
Clerc F, Reiding KR, Jansen BC, Kammeijer GSM, Bondt A, Wuhrer M. Human plasma protein N-glycosylation. Glycoconj J 2015; 33:309-43. [PMID: 26555091 PMCID: PMC4891372 DOI: 10.1007/s10719-015-9626-2] [Citation(s) in RCA: 293] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 01/09/2023]
Abstract
Glycosylation is the most abundant and complex protein modification, and can have a profound structural and functional effect on the conjugate. The oligosaccharide fraction is recognized to be involved in multiple biological processes, and to affect proteins physical properties, and has consequentially been labeled a critical quality attribute of biopharmaceuticals. Additionally, due to recent advances in analytical methods and analysis software, glycosylation is targeted in the search for disease biomarkers for early diagnosis and patient stratification. Biofluids such as saliva, serum or plasma are of great use in this regard, as they are easily accessible and can provide relevant glycosylation information. Thus, as the assessment of protein glycosylation is becoming a major element in clinical and biopharmaceutical research, this review aims to convey the current state of knowledge on the N-glycosylation of the major plasma glycoproteins alpha-1-acid glycoprotein, alpha-1-antitrypsin, alpha-1B-glycoprotein, alpha-2-HS-glycoprotein, alpha-2-macroglobulin, antithrombin-III, apolipoprotein B-100, apolipoprotein D, apolipoprotein F, beta-2-glycoprotein 1, ceruloplasmin, fibrinogen, immunoglobulin (Ig) A, IgG, IgM, haptoglobin, hemopexin, histidine-rich glycoprotein, kininogen-1, serotransferrin, vitronectin, and zinc-alpha-2-glycoprotein. In addition, the less abundant immunoglobulins D and E are included because of their major relevance in immunology and biopharmaceutical research. Where available, the glycosylation is described in a site-specific manner. In the discussion, we put the glycosylation of individual proteins into perspective and speculate how the individual proteins may contribute to a total plasma N-glycosylation profile determined at the released glycan level.
Collapse
Affiliation(s)
- Florent Clerc
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
| | - Karli R Reiding
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
| | - Bas C Jansen
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
| | - Guinevere S M Kammeijer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
| | - Albert Bondt
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands.,Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands. .,Division of BioAnalytical Chemistry, VU University Amsterdam, Amsterdam, The Netherlands.
| |
Collapse
|
7
|
Aksenov DV, Medvedeva LA, Skalbe TA, Sobenin IA, Tertov VV, Gabbasov ZA, Popov EV, Orekhov AN. Deglycosylation of apo B-containing lipoproteins increase their ability to aggregate and to promote intracellular cholesterol accumulation in vitro. Arch Physiol Biochem 2008; 114:349-56. [PMID: 19085234 DOI: 10.1080/13813450802227915] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Sub-fractions of all apo B-100 containing lipoproteins (low density lipoproteins, very low density lipoproteins and intermediate density lipoproteins) with reduced contents of sialic acid were found in vivo in human blood. These lipoproteins were inclined to spontaneously form aggregates and were able to stimulate accumulation of cholesterol in cells cultured from human aortic intima. In vitro treatment of apo B-containing lipoproteins with 2,6- and 2,3-specific sialidases, alpha-mannosidase, endoglycosidases F1 or F2 or peptide-N-glycanase F also stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in cells of the intact human aortic intima. So, deglycosylation of various apo B-containing lipoproteins possibly occurs in the blood, decreases their resistance to aggregation and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, thereby increasing their atherogenic potential.
Collapse
Affiliation(s)
- D V Aksenov
- Institute of Experimental Cardiology, Russian Cardiology Research Center, Moscow, Russia.
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Mel'nichenko AA, Tertov VV, Ivanova OA, Aksenov DV, Sobenin IA, Popov EV, Kaplun VV, Suprun IV, Panasenko OM, Orekhov AN. Desialylation Decreases the Resistance of Apo B-Containing Lipoproteins to Aggregation and Increases Their Atherogenic Potential. Bull Exp Biol Med 2005; 140:51-4. [PMID: 16254619 DOI: 10.1007/s10517-005-0409-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Subfractions of apo B-containing lipoproteins (VLDL and intermediate-density lipoproteins) with reduced content of sialic acid were found in human blood. These lipoproteins are characterized by high capacity to spontaneous association (aggregation) and stimulated accumulation of cholesterol in smooth muscle cells of human aortic intima. In vitro treatment of apo B-containing lipoproteins with alpha-2,6-sialidase and alpha-2,3-sialidase stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in smooth muscle cells of the intact human aortic intima. Probably, desialylation of various apo B-containing lipoproteins can occur in the blood; this process decreases their resistance to aggregation, and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, i.e. increases their atherogenic potential.
Collapse
Affiliation(s)
- A A Mel'nichenko
- Laboratory of Physicochemical Methods for Study and Analysis, Institute of Physicochemical Medicine, Russian Ministry of Health, Moscow.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Harazono A, Kawasaki N, Kawanishi T, Hayakawa T. Site-specific glycosylation analysis of human apolipoprotein B100 using LC/ESI MS/MS. Glycobiology 2004; 15:447-62. [PMID: 15616123 DOI: 10.1093/glycob/cwi033] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Human apolipoprotein B100 (apoB100) has 19 potential N-glycosylation sites, and 16 asparagine residues were reported to be occupied by high-mannose type, hybrid type, and monoantennary and biantennary complex type oligosaccharides. In the present study, a site-specific glycosylation analysis of apoB100 was carried out using reversed-phase high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/ESI MS/MS). ApoB100 was reduced, carboxymethylated, and then digested by trypsin or chymotrypsin. The complex mixture of peptides and glycopeptides was subjected to LC/ESI MS/MS, where product ion spectra of the molecular ions were acquired data-dependently. The glycopeptide ions were extracted and confirmed by the presence of carbohydrate-specific fragment ions, such as m/z 204 (HexNAc) and 366 (HexHexNAc), in the product ion spectra. The peptide moiety of glycopeptide was determined by the presence of the b- and y-series ions derived from its amino acid sequence in the product ion spectrum, and the oligosaccharide moiety was deduced from the calculated molecular mass of the oligosaccharide. The heterogeneity of carbohydrate structures at 17 glycosylation sites was determined using this methodology. Our data showed that Asn2212, not previously identified as a site of glycosylation, could be glycosylated. It was also revealed that Asn158, 1341, 1350, 3309, and 3331 were occupied by high-mannose type oligosaccharides, and Asn 956, 1496, 2212, 2752, 2955, 3074, 3197, 3438, 3868, 4210, and 4404 were predominantly occupied by mono- or disialylated oligosaccharides. Asn3384, the nearest N-glycosylation site to the LDL-receptor binding site (amino acids 3359-3369), was occupied by a variety of oligosaccharides, including high-mannose, hybrid, and complex types. These results are useful for understanding the structure of LDL particles and oligosaccharide function in LDL-receptor ligand binding.
Collapse
Affiliation(s)
- Akira Harazono
- National Institute of Health Sciences, Division of Biological Chemistry and Biologicals, 1-18-1 Kami-yoga, Setagaya-Ku, Tokyo 158-8501, Japan.
| | | | | | | |
Collapse
|
10
|
Kveder M, Pifat G, Gavella M, Lipovac V. Effect of gangliosides on the copper-induced oxidation of human low-density lipoproteins. Biophys Chem 2003; 104:45-54. [PMID: 12834826 DOI: 10.1016/s0301-4622(02)00337-x] [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: 11/24/2022]
Abstract
The role of gangliosides in the copper-induced oxidative modification of human low-density lipoprotein (LDL) was studied focusing on the early stage of LDL oxidation in which the concentration of conjugated dienes increases only weakly. The changes in the protein and lipid component were followed using fluorescence spectroscopy. The results indicate that binding of gangliosides to LDL causes slower destruction of tryptophan fluorescence and suppresses cross-linking between the reactive groups of the protein and the products of lipid peroxidation. The protective role of gangliosides could be assigned to their interference with the lipid-protein interaction in the LDL particle, which might be important for the maintenance of the native plasma antioxidant status in vivo.
Collapse
Affiliation(s)
- Marina Kveder
- Ruder Bosković Institute, Bijenicka 54, 10000 Zagreb, Croatia.
| | | | | | | |
Collapse
|
11
|
Hannuksela ML, Liisanantti MK, Savolainen MJ. Effect of alcohol on lipids and lipoproteins in relation to atherosclerosis. Crit Rev Clin Lab Sci 2002; 39:225-83. [PMID: 12120782 DOI: 10.1080/10408360290795529] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Several studies indicate that light-to-moderate alcohol consumption is associated with a low prevalence of coronary heart disease. An increase in high-density lipoprotein (HDL) cholesterol is associated with alcohol intake and appears to account for approximately half of alcohol's cardioprotective effect. In addition to changes in the concentration and composition of lipoproteins, alcohol consumption may alter the activities of plasma proteins and enzymes involved in lipoprotein metabolism: cholesteryl ester transfer protein, phospholipid transfer protein, lecithin:cholesterol acyltransferase, lipoprotein lipase, hepatic lipase, paraoxonase-1 and phospholipases. Alcohol intake also results in modifications of lipoprotein particles: low sialic acid content in apolipoprotein components of lipoprotein particles (e.g., HDL apo E and apo J) and acetaldehyde modification of apolipoproteins. In addition, "abnormal" lipids, phosphatidylethanol, and fatty acid ethyl esters formed in the presence of ethanol are associated with lipoproteins in plasma. The effects of lipoproteins on the vascular wall cells (endothelial cells, smooth muscle cells, and monocyte/macrophages) may be modulated by ethanol and the alterations further enhanced by modified lipids. The present review discusses the effects of alcohol on lipoproteins in cholesterol transport, as well as the novel effects of lipoproteins on vascular wall cells.
Collapse
Affiliation(s)
- Minna L Hannuksela
- Department of Internal Medicine, Biocenter Oulu, University of Oulu, Finland
| | | | | |
Collapse
|
12
|
|
13
|
Tertov VV, Kaplun VV, Sobenin IA, Boytsova EY, Bovin NV, Orekhov AN. Human plasma trans-sialidase causes atherogenic modification of low density lipoprotein. Atherosclerosis 2001; 159:103-15. [PMID: 11689212 DOI: 10.1016/s0021-9150(01)00498-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In earlier studies we have found that incubation of low density lipoprotein (LDL) with autologous blood plasma-derived serum leads to a loss of sialic acid from lipoprotein particles. In this study we demonstrated that sialic acid removed from LDL was transferred to glycoconjugates of lipoproteins, glycoproteins and sphingolipids of human serum. This showed that human serum contained the trans-sialidase activity. Gel-filtration chromatography of human blood serum demonstrated the presence of trans-sialidase activity in lipoprotein subfractions as well as in lipoprotein-deficient serum. Trans-sialidase (about 65 kDa) was isolated from lipoprotein-deficient serum using affinity chromatography carried out with Neu5Acalpha2-8Neu5Ac-sepharose FF-6. Optimal pH values for the trans-sialidase were 3.0, 5.0 and 7.0. Calcium and magnesium ions stimulated the enzyme activity at millimolar concentrations. Isolated enzyme can remove sialic acid from LDL, IDL, VLDL, and HDL particles (in decreasing rate order). Serum trans-sialidase transferred sialic acid from glycoconjugates of plasma proteins (fetuin, transferrin) and gangliosides (GM3, GD3, GM1, GD1a, GD1b). Sialylated glycoconjugates of human blood erythrocytes also served as substrate for serum trans-sialidase. We have found that sialic acid can also be removed from N- and O-linked glycans, sialylated Le(x) and Le(a), oligosialic acids, and sphingolipid carbohydrate chains. The rate of sialic acid release decreased in the following order: alpha2,6>alpha2,3>>alpha2,8. Transferred molecule of sialic acid can form alpha2,6, alpha2,3 and to a lesser degree alpha2,8 linkage with galactose, N-acetyl-galactosamine or sialic acid of acceptors. The glycoconjugates of erythrocytes, lipoprotein particles, plasma proteins, neutral sphingolipids and gangliosides may serve as acceptors of transferred sialic acid. Trans-sialidase-treated native LDL becomes desialylated and then can induce cholesteryl ester accumulation in human aortic intimal smooth muscle cells. Thus, trans-sialidase may be involved in the early stages of atherogenesis characterized by foam cell formation.
Collapse
Affiliation(s)
- V V Tertov
- Institute of Experimental Cardiology, Cardiology Research Center, Institute for Atherosclerosis Research Ltd, 121552, Moscow, Russia
| | | | | | | | | | | |
Collapse
|
14
|
Garner B, Harvey DJ, Royle L, Frischmann M, Nigon F, Chapman MJ, Rudd PM. Characterization of human apolipoprotein B100 oligosaccharides in LDL subfractions derived from normal and hyperlipidemic plasma: deficiency of alpha-N-acetylneuraminyllactosyl-ceramide in light and small dense LDL particles. Glycobiology 2001; 11:791-802. [PMID: 11588155 DOI: 10.1093/glycob/11.10.791] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The carbohydrate composition of apolipoprotein (apo) B100, particularly its degree of sialylation, may contribute to the atherogenic properties of low-density lipoprotein (LDL). We analyzed LDL apoB100 glycans derived from normolipidemic, hypercholesterolemic, and hypertriglyceridemic diabetic subjects. Using exoglycosidase carbohydrate sequencing and matrix-assisted laser desorption/ionization mass spectrometry to analyze fluorescently labeled oligosaccharides, we report evidence for several carbohydrates not previously identified on apoB100, including truncated complex biantennary N-glycans and hybrid N-glycans. The distribution and diversity of the apoB100 glycans isolated from all individuals was highly conserved. The N-glycan composition of apoB100 derived from five LDL subpopulations (LDL1, d = 1.018-1.023; LDL2, d = 1.023-1.030; LDL3, d = 1.030-1.040; LDL4, d = 1.040-1.051; LDL5, d = 1.051-1.065 g/ml) did not vary in normolipidemic or hypercholesterolemic subjects. Furthermore, we found no evidence for "desialylated" apoB100 glycans in any of the samples analyzed. Analysis of the most abundant LDL ganglioside, alpha-N-acetylneuraminyllactosyl-ceramide, revealed a deficiency in small dense LDL and in the most buoyant subpopulation. These data provide a novel explanation for the apparent deficiency of sialic acid in small dense LDL and indicate that the global apoB100 N-glycan composition is invariable in the patient groups studied.
Collapse
Affiliation(s)
- B Garner
- Oxford Glycobiology Institute, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | | | | | | | | | | | | |
Collapse
|
15
|
Fujioka Y, Taniguchi T, Ishikawa Y, Yokoyama M. Significance of acidic sugar chains of apolipoprotein B-100 in cellular metabolism of low-density lipoproteins. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 136:355-62. [PMID: 11079462 DOI: 10.1067/mlc.2000.110103] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have elucidated the carbohydrate structures of the N-linked sugar chains of human and rabbit apolipoprotein B-100 (apo B-100), which is similar in composition to oligosaccharides (Arch Biochem Biophys 1989;273:197-205, Arteriosclerosis 1990; 10:386-93). We have also shown the negative correlation of the ratio of acidic sugar chains of apo B-100 to the serum cholesterol levels in Watanabe heritable hyperlipidemic rabbits (Atherosclerosis 1992;93:229-35). The acidity of sugar chains is determined by the existence of sialic acid residues at the terminal of oligosaccharides. In the present study we investigated N-linked sugar chains of apo B-100 from patients with coronary artery disease (CAD) who had moderate hypercholesterolemia (less than 400 mg/dL). There was no difference in the structure of their oligosaccharides and the ratio of acidic sugar chains of apo B-100 from CAD patients as compared with that from healthy individuals reported previously. To clarify the role of sialic acid residues in apo B-100 for lipoprotein metabolism, we studied cellular uptake of low-density lipoproteins (LDLs) treated with sialidase (desialylated LDL). Desialylated LDLs were taken up and degraded to a 2-fold greater degree than control LDL by human monocyte-derived macrophages and stimulated cholesterol esterification in these cells. These results indicate that sialic acid residues of apo B- 100 play an important role in cellular uptake and degradation of LDL.
Collapse
Affiliation(s)
- Y Fujioka
- The First Department of Internal Medicine and The Faculty of Health Sciences, Kobe University School of Medicine, Japan
| | | | | | | |
Collapse
|
16
|
Lindbohm N, Gylling H, Rajaratnam RA, Miettinen TA. Sialic acid content of low-density lipoprotein in women with coronary artery disease. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 136:110-5. [PMID: 10945239 DOI: 10.1067/mlc.2000.108148] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A low sialic acid content in low-density lipoprotein (LDL) has been associated with coronary artery disease (CAD) in studies that have included mostly male subjects. We compared the sialic acid-to-apolipoprotein B ratios of total LDL and its subfractions in middle-aged women with CAD (CAD+, n = 22) with those ratios in healthy female control subjects (CAD-, n = 11). CAD+ subjects had a lower sialic acid ratio in total LDL and in its subfractions as compared with results in CAD- subjects. In total, light, and dense LDL, the sialic acid ratio was negatively correlated with the respective cholesterol and phospholipid concentrations, and in very dense LDL, it was negatively correlated with triglyceride concentration. In multivariate analysis, CAD and LDL cholesterol contributed to the explanation of the variability of LDL sialic acid ratios. In summary, a low sialic acid-to-apolipoprotein B ratio in LDL was associated with the presence of CAD in middle-aged women with mild to moderate hypercholesterolemia.
Collapse
Affiliation(s)
- N Lindbohm
- Department of Medicine, Helsinki University Central Hospital, Finland
| | | | | | | |
Collapse
|
17
|
Lindbohm N, Gylling H, Miettinen TA. Sialic acid content of low density lipoprotein and its relation to lipid concentrations and metabolism of low density lipoprotein and cholesterol. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32017-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
18
|
Lindbohm N, Gylling H, Miettinen TE, Miettinen TA. Sialic acid content of LDL and lipoprotein metabolism in combined hyperlipidemia and primary moderate hypercholesterolemia. Clin Chim Acta 1999; 285:69-84. [PMID: 10481924 DOI: 10.1016/s0009-8981(99)00107-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Low density lipoprotein (LDL) with low sialic acid content has been shown to cause intracellular lipid accumulation and therefore is suggested to be atherogenic. We investigated the sialic acid content of total LDL and its subfractions, and their relations to lipoprotein kinetics in 22 subjects with primary moderate hypercholesterolemia (IIa) and in 21 subjects with combined hyperlipidemia (IIb) matched for age, sex, BMI and the frequency of coronary artery disease. Sialic acid to protein ratio decreased gradually from VLDL and IDL to light and dense LDL and HDL, but was high in very dense LDL probably due to presence of Lp(a). Sialic acid to apo B ratio was significantly lower in dense and very dense subfractions of IIb than IIa. The sialic acid/apo B ratios of dense and very dense LDL subfractions were interrelated and were negatively associated with their cholesterol and triglyceride concentrations, and with the transport rate (TR) for dense LDL apo B. The only metabolic variable differing between the groups was the TR for dense LDL apo B, which was significantly higher in IIb vs. IIa. In addition, the TR for dense LDL apo B was positively associated with the esterification percentage of LDL cholesterol. In conclusion, low sialic acid content in dense and very dense LDL subfractions was associated with enhanced TR for LDL apo B and type IIb dyslipidemia.
Collapse
Affiliation(s)
- N Lindbohm
- Department of Medicine, University of Helsinki, Finland
| | | | | | | |
Collapse
|
19
|
Sobenin IA, Tertov VV, Orekhov AN. Optimization of the assay for sialic acid determination in low density lipoprotein. J Lipid Res 1998. [DOI: 10.1016/s0022-2275(20)32485-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
20
|
Chappey B, Beyssen B, Foos E, Ledru F, Guermonprez JL, Gaux JC, Myara I. Sialic acid content of LDL in coronary artery disease: no evidence of desialylation in subjects with coronary stenosis and increased levels in subjects with extensive atherosclerosis and acute myocardial infarction: relation between desialylation and in vitro peroxidation. Arterioscler Thromb Vasc Biol 1998; 18:876-83. [PMID: 9633926 DOI: 10.1161/01.atv.18.6.876] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We recently showed that sialic acid content of LDL was not a marker of early cardiovascular disease (Arterioscler Thromb Vasc Biol. 1995;15:334-339). Here, we investigated this parameter in patients with advanced coronary artery disease (CAD). We first examined 100 patients having undergone coronary angiography. The distribution of LDL sialic acid values was very similar in subjects with no coronary stenosis (31.3+/-3.7 nmol/mg LDL protein, mean+/-SD) and those with > or = 75% stenosis in at least one main coronary artery or > or = 50% stenosis in at least two main coronary arteries (32.1+/-5.5 nmol/mg LDL protein). In contrast, LDL sialic acid content was significantly increased in patients with both coronary stenosis and peripheral arterial atherosclerotic lesions compared with those with either no lesion or only one or the other type of lesion. We then examined LDL sialic acid content in 20 patients with acute myocardial infarction. LDL sialic acid content was significantly higher (35.9+/-3.2 nmol/mg LDL protein) than that in the CAD(-) control group. These data suggest that LDL sialic acid content increases with the extension of atherosclerosis and its progression to acute complications. To explain the discordance with Orekhov and coworkers (Atherosclerosis. 1991;86:153-161), who showed that LDL sialic acid content in patients with advanced CAD was lower than that in healthy subjects, we studied the time courses of sialic acid, TBARS, and vitamin E levels in LDL dialyzed in different experimental conditions. A continuous decrease in both sialic acid and vitamin E levels and an increase in TBARS levels were observed in LDL samples containing less than 1 mmol/L EDTA, the intensity and rapidity of which varied with the EDTA concentration in the buffer. Our data support the idea that desialylation may result from in vitro peroxidation of LDL.
Collapse
Affiliation(s)
- B Chappey
- Laboratoire de Biochimie Appliquée, Faculté des Sciences Pharmaceutiques et Biologiques, Châtenay-Malabry, France
| | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
In this review an updated overview of current improvements on thin-layer chromatography (TLC) of gangliosides over the past decade is provided. Basic general techniques and special advice is given for successful separation of glycosphingolipids. New approaches concerning continuous and multiple development, and several preparative TLC methods are also included. Emphasis is placed on TLC immunostaining and related techniques, i.e. practical applications of carbohydrate-specific antibodies, toxins and bacteria, viruses, lectins and eukaryotic cells. Thus, this review on ganglioside TLC summarizes its power as an analytical tool for a wide range of purposes.
Collapse
Affiliation(s)
- J Müthing
- Institute of Cell Culture Technology, Faculty of Technical Sciences, University of Bielefeld, Germany
| |
Collapse
|
22
|
Affiliation(s)
- K Balakrishnan
- Biotechnology Unit, Council of Scientific and Industrial Research, Trivandrum, India
| | | |
Collapse
|
23
|
Chappey B, Myara I, Giral P, Kerharo G, Plainfosse MC, Levenson J, Simon A, Moatti N. Evaluation of the sialic acid content of LDL as a marker of coronary calcification and extracoronary atherosclerosis in asymptomatic hypercholesterolemic subjects. PCVMETRA Group. Arterioscler Thromb Vasc Biol 1995; 15:334-9. [PMID: 7749843 DOI: 10.1161/01.atv.15.3.334] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Recent studies have shown that the sialic acid content of LDL isolated from patients with angiographically demonstrated advanced coronary atherosclerosis is lower than that of LDL isolated from healthy subjects. These observations raise the question as to whether LDL sialic acid content could be used as an early marker of atherosclerosis. We screened for carotid, aortic, and femoral plaques by ultrasonography and for coronary calcifications by ultrafast computed tomography in 160 hypercholesterolemic subjects free of cardiovascular disease to investigate the relation between LDL sialic acid content and the prevalence of these early atherosclerotic lesions. LDL sialic acid values varied from 19.6 to 46.6 nmol/mg LDL protein (33.9 +/- 4.4, mean +/- SD) in the whole population, but the distribution was very similar: (1) in subjects with no plaque (34.1 +/- 4.9) relative to those with one or several plaques at one (34.2 +/- 4.4), two (33.0 +/- 3.6), or three (34.8 +/- 3.4) different arterial sites; (2) in subjects with (33.9 +/- 3.7) and without (34.1 +/- 4.8) coronary calcification; and (3) in subjects with both extracoronary and coronary lesions (33.8 +/- 3.9) relative to those with no arterial lesions (34.2 +/- 4.5). LDL sialic acid content was not related to sex, age, body mass index, smoking, blood pressure, or serum total cholesterol and lipoprotein(a) levels but correlated negatively with serum triglyceride levels (P < .001). These results suggest that LDL sialic acid content is not a discriminant marker of early atherosclerosis in asymptomatic hypercholesterolemic subjects.
Collapse
Affiliation(s)
- B Chappey
- Laboratoire de Biochemie, Faculté des Sciences Pharmaceutiques et Biologiques, Chatenay-Malabry, France
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Fujioka Y, Taniguchi T, Ishikawa Y, Shiomi M, Yokoyama M. Relation of N-glycosylation of apolipoprotein B-100 to cellular metabolism of low density lipoprotein. Atherosclerosis 1994; 108:91-102. [PMID: 7980710 DOI: 10.1016/0021-9150(94)90040-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We studied the functional role of N-linked sugar chains of apolipoprotein (apo) B-100 of low density lipoprotein (LDL) in cholesterol metabolism. The N-linked sugar chains of apo B-100 of LDL obtained from four homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits were liberated by hydrazinolysis, followed by NaB3H4 reduction and were fractionated by paper electrophoresis and column chromatography. They consisted of one neutral (N) and two acidic (A1, A2) fractions. The ratio of apo B-100 acidic fractions (A1+A2) varied among 4 WHHL rabbits. Serial measurements of serum cholesterol levels showed that they decreased with aging in each of 4 WHHL rabbits. We investigated the relation of the ratio of acidic sugar chains of apo B-100 to the serum cholesterol levels. Reciprocals of the serum cholesterol levels were significantly correlated with the ratio of acidic sugar chains of apo B-100 (r = 0.901, P < 0.001). To elucidate the role of N-linked sugar chains of apo B-100, we investigated cellular uptake of LDL in normal rabbit skin fibroblasts. The amounts of association, degradation and cholesteryl esterification of LDL with a lower ratio of acidic sugar chains at 37 degrees C were greater than those of LDL with a higher ratio of acidic sugar chains. These results suggest that N-glycosylation of apo B-100 may be related with serum cholesterol levels and N-linked sugar chains of apo B-100 may play an important role in cellular metabolism of LDL.
Collapse
Affiliation(s)
- Y Fujioka
- First Department of Internal Medicine, Kobe University School of Medicine, Japan
| | | | | | | | | |
Collapse
|
25
|
Abstract
The ganglioside levels in atherosclerotic lesions of human aorta are considerably higher than those in unaffected areas of aorta, and atherosclerotic patients frequently have increased concentrations of serum gangliosides. The present review summarizes recent findings that suggest the possible involvement of aortic gangliosides in platelet activation and adhesion of platelets to the vessel wall. The effect of gangliosides on the structure of low density lipoproteins (LDL), on the interaction of LDL with macrophages and hepatic cells and on the LDL-regulated biosynthesis of cholesterol is also discussed. In vitro experiments have demonstrated that a major ganglioside of the intima of atherosclerotic aorta induces rapid adhesion, aggregation and spreading of platelets. Moreover, gangliosides present in elevated amounts in the intercellular space of atherosclerotic aortic tissue modify the surface structure and stimulate aggregation of LDL. Ganglioside-modified LDL are readily recognized and taken up by macrophages, while preincubation of LDL with low concentrations of gangliosides inhibits LDL binding to hepatic cells. Thus, ganglioside enrichment of LDL is likely to interfere with LDL clearance via the hepatic cells. Thus, ganglioside enrichment of LDL is likely to interfere with LDL clearance via the hepatic LDL receptor, and to stimulate binding of LDL to the scavenger receptor of macrophages. It is postulated that high ganglioside levels in the aorta and serum may be an additional risk factor in atherosclerosis.
Collapse
Affiliation(s)
- N V Prokazova
- Institute of Experimental Cardiology, Academy of Medical Sciences, Moscow, Russia
| | | |
Collapse
|
26
|
Tertov VV, Orekhov AN, Sobenin IA, Morrisett JD, Gotto AM, Guevara JG. Carbohydrate composition of protein and lipid components in sialic acid-rich and -poor low density lipoproteins from subjects with and without coronary artery disease. J Lipid Res 1993. [DOI: 10.1016/s0022-2275(20)40729-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
27
|
Pifat G, Brnjas-Kraljević J, Jürgens G, Herak-Kramberger CM, Herak JN. Chemical modification of low-density lipoprotein enhances the number of binding sites for divalent cations. Chem Phys Lipids 1992; 63:159-67. [PMID: 1337315 DOI: 10.1016/0009-3084(92)90032-k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The EPR technique with paramagnetic Mn(II) ions has been used to probe the negatively charged sites on the surface of modified low-density lipoprotein (LDL). LDL modified in five different ways exhibited increased binding capacity for divalent cations. Enhanced binding is caused by the increase in the number of 'strong' binding sites. The 'strong' sites have been identified to be the aspartic acid and/or glutamic acid carboxyl residues and the 'weak' sites are zwitter-ionic phospholipids. In native LDL the negative groups make 'bonds' with the positive lysyl residues, thus stabilizing the structure. Any deprotonation or modification of the lysine amino groups makes the LDL structure more loose and the amino acid carboxyl groups accessible to divalent cations.
Collapse
Affiliation(s)
- G Pifat
- Rudjer Bosković Institute, University of Zagreb, Croatia
| | | | | | | | | |
Collapse
|
28
|
Tsunemitsu M, Ishikawa Y, Taniguchi T, Fukuzaki H, Yokoyama M. Association of N-glycosylation of apolipoprotein B-100 with plasma cholesterol levels in Watanabe heritable hyperlipidemic rabbits. Atherosclerosis 1992; 93:229-35. [PMID: 1590827 DOI: 10.1016/0021-9150(92)90259-j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have previously demonstrated the heterogeneity of N-linked sugar chains of apolipoprotein (apo) B-100 in Watanabe heritable hyperlipidemic (WHHL) rabbit and fasting Japanese White rabbits (Arteriosclerosis, 10 (1990) 386-393). To investigate further the role of N-linked sugar chains of apo B-100 in lipid metabolism, we examined the correlation between the N-glycosylation of apo B-100 and serum cholesterol levels in WHHL rabbits. The N-linked sugar chains of apo B-100 were liberated by hydrazinolysis, followed by NaB3H4 reduction and were fractionated by paper electrophoresis and BioGel P-4 column chromatography. These were found to consist of one neutral (N) and two acidic fractions (A1 and A2). N contained a high mannose type oligosaccharide consisting of Man5.GlcNAc2 to Man9.GlcNAc2, while A1 and A2 contained monosialylated and disialylated complex type oligosaccharides, respectively. The molar ratio varied among the 5 WHHL rabbits. There was an inverse correlation between the ratio of acidic oligosaccharide fractions (A1 + A2) and serum cholesterol levels (r = -0.971, P less than 0.01) in the 5 WHHL rabbits. These results indicate that the N-glycosylation of apo B-100 is closely related to cholesterol metabolism in WHHL rabbits.
Collapse
Affiliation(s)
- M Tsunemitsu
- First Department of Internal Medicine, Kobe University School of Medicine, Japan
| | | | | | | | | |
Collapse
|
29
|
Dousset N, Dousset JC, Soléra ML, Valdiguié P. Desialylated low density lipoproteins and atherosclerosis. EXS 1992; 62:158-63. [PMID: 1450583 DOI: 10.1007/978-3-0348-7460-1_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Oxidative modification of LDL is accompanied by a number of compositional and structural changes, now well known. In addition, other atherogenic modifications of LDL exist, such as desialylation. The present article summarizes the recent data related to desialylated LDL and to the presence of these LDL in blood plasma of patients with coronary atherosclerosis. In addition, this review examines the sensitivity of these LDL to peroxidative stress.
Collapse
Affiliation(s)
- N Dousset
- Department of Biochemistry, Rangueil University Hospital, Toulouse, France
| | | | | | | |
Collapse
|
30
|
Mikhailenko IA, Dubrovskaya SA, Korepanova OB, Timofeeva NG, Morozkin AD, Prokazova NV, Bergelson LD. Interaction of low-density lipoproteins with gangliosides. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1085:299-305. [PMID: 1911863 DOI: 10.1016/0005-2760(91)90133-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The ganglioside uptake capacity of human serum low-density lipoproteins (LDL), the mode of ganglioside-LDL binding, and the influence of gangliosides on the floatation properties, size distribution, stability and fluorescence of LDL were investigated. The data obtained suggest that both hydrophobic and electrostatic forces are involved in formation of ganglioside-LDL complexes, but the former appear to be more important. Although association of gangliosides with LDL is predominantly unspecific, nonsaturable, and weak, a small saturable component due to specific ganglioside-apolipoprotein binding, also appears to be involved. In the presence of gangliosides the lipoprotein particles aggregate, the intrinsic fluorescence of LDL and their interaction with antibodies against apo-B change indicating that the state of apo-B [corrected] is modified by gangliosides.
Collapse
Affiliation(s)
- I A Mikhailenko
- Institute of Experimental Cardiology, U.S.S.R. Academy of Medical Sciences, Moscow
| | | | | | | | | | | | | |
Collapse
|
31
|
|
32
|
Windler E, Greeve J, Levkau B, Kolb-Bachofen V, Daerr W, Greten H. The human asialoglycoprotein receptor is a possible binding site for low-density lipoproteins and chylomicron remnants. Biochem J 1991; 276 ( Pt 1):79-87. [PMID: 1645533 PMCID: PMC1151146 DOI: 10.1042/bj2760079] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Binding and internalization of chylomicron remnants from rat mesenteric lymph by HepG2 cells was inhibited by both excess remnants and low-density lipoprotein (LDL) to the same extent. Ligand blots revealed binding of remnants and LDL to the LDL receptor. Measures regulating LDL receptor activity greatly influenced the binding of remnants: ethinyloestradiol, the hydroxymethylglutaryl-CoA reductase inhibitor pravastatin and the absence of LDL all increased binding, whereas high cell density or the presence of LDL decreased binding. Also, asialofetuin, asialomucin, the neoglycoprotein galactosyl-albumin and an antibody against the asialoglycoprotein receptor all decreased substantially the binding of remnants. At high cell density, binding internalization and degradation of chylomicron remnants was inhibited by up to 70-80%, yet binding of LDL was inhibited by no more than 20-30%. In cross-competition studies, the binding of 125I-asialofetuin was efficiently competed for by asialofetuin itself or by the antibody, and also by LDL and remnants, yet remnants displayed an approx. 100-fold higher affinity than LDL. Likewise, remnants of human triacylglycerol-rich lipoproteins and asialofetuin interfered with each others' binding to HepG2 cells or human liver membranes. It is concluded that the LDL receptor mediates the internalization of chylomicron remnants into hepatocytes depending on its activity, according to demand for cholesterol. Additionally, the asialoglycoprotein receptor may contribute to the endocytosis of LDL, but predominantly of chylomicron remnants.
Collapse
Affiliation(s)
- E Windler
- Medizinische Kernklinik und Poliklinik, Universitäts-Krankenhaus Eppendorf, Hamburg, Federal Republic of Germany
| | | | | | | | | | | |
Collapse
|
33
|
Orekhov AN, Tertov VV, Mukhin DN. Desialylated low density lipoprotein--naturally occurring modified lipoprotein with atherogenic potency. Atherosclerosis 1991; 86:153-61. [PMID: 1872910 DOI: 10.1016/0021-9150(91)90211-k] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have recently established that low density lipoprotein (LDL) of most patients with coronary atherosclerosis differs from the LDL of most healthy subjects by its ability to cause primary atherosclerotic changes, i.e. the accumulation of intracellular cholesterol in the cells of smooth muscle origin cultured from unaffected intima of human aorta. Patients' LDL has a 2.5-5-fold lower content of sialic acid as compared with the LDL of healthy subjects. On the other hand, desialylation of native LDL with neuraminidase makes it capable of causing accumulation of intracellular cholesterol similar to patients' LDL. In the present study we showed that LDL of patients and healthy donors did not differ in the content and composition of protein and lipids. Thus, the difference in the content of sialic acid is the only difference observed between atherogenic LDL of patients and nonatherogenic LDL of healthy donors. A low content of sialic acid is characteristic of both protein and lipid moiety of LDL particle. Sialic acid content was determined in individual LDL preparations obtained from patients and healthy donors. The sialic acid of LDL preparations of 25 out of 27 patients was below 18 micrograms/mg protein. LDL from 2 patients with higher sialic acid content proved to be normal. The ability of patients' LDL and LDL desialylated with neuraminidase in vitro to cause the accumulation of intracellular lipids correlated with the degree of lipoprotein desialylation. Apparently, the ability of patients' LDL to stimulate the cellular lipid accumulation may be explained by a deficiency of sialic acid in the lipoprotein particle.
Collapse
Affiliation(s)
- A N Orekhov
- Institute of Experimental Cardiology, U.S.S.R. Cardiology Research Center, Moscow
| | | | | |
Collapse
|
34
|
Ledvinova J, Iwamori M, Nagai Y. Characteristic binding of human plasma apolipoprotein B to gangliotetraosylceramide and gangliotriaosylceramide. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 194:507-11. [PMID: 1702710 DOI: 10.1111/j.1432-1033.1990.tb15645.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The binding of human plasma low-density lipoproteins (LDL), freshly prepared by discontinuous ultracentrifugation, to several neutral and acidic glycosphingolipids was examined by TLC immunostaining with the anti [apolipoprotein B (apoB)] antibody. ApoB was found to bind characteristically to the asialogangliosides, gangliotetraosylceramide (Gg4Cer) and gangliotriaosylceramide (Gg3Cer), the former being a more potent receptor than the latter, indicating that the sequences Gal beta 1-3GalNAc beta 1-4Gal and GalNAc beta 1-4Gal are involved in the binding of apoB. A weak positive reaction with fucosylgangliotetraosylceramide (IV2Fuc-Gg4Cer), which has the same internal recognition sequences, was also observed (the binding ability was only 1/7 of that in the case of Gg4Cer). No binding to other neutral glycosphingolipids, or glycosphingolipid sulfates (I3-SO3-GalCer) and gangliosides, was detected, and therefore substitution of the receptor glycolipid with sialic acid was thought to inhibit the binding. The results indicate that, along with the binding of apoB to the LDL-binding domain of the receptor glycoprotein, interaction with some carbohydrate chains in the receptor, or with glycolipids coexisting on the plasma membrane, may be important for the binding of apoB to cells.
Collapse
Affiliation(s)
- J Ledvinova
- Department of Biochemistry, Faculty of Medicine, University of Tokyo, Japan
| | | | | |
Collapse
|
35
|
La Belle M, McCall MR, Krauss RM, Forte TM. Unique structural properties of apolipoprotein B in low-density lipoproteins produced by several human hepatoma-derived cell lines. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1046:288-93. [PMID: 2171671 DOI: 10.1016/0005-2760(90)90243-q] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Previous work has shown that low-density lipoproteins (LDL) secreted by hepatoma-derived cell lines have an unusual composition compared to plasma LDL; rather than cholesteryl ester, the hepatoma cell-secreted LDL have a triacylglycerol core. We have found that they also have an increased negative charge, as judged by agarose electrophoresis. Since apolipoprotein B is a glycoprotein containing carbohydrate chains terminated with negatively charged sialic acid residues, we examined whether increased glycosylation of the apolipoprotein B from three hepatoma cell lines (Hep G2, Hep 3B and Huh 7) might account for the differences in LDL charge. The weight percent carbohydrate for Hep G2, Hep 3B and Huh 7 LDL-protein (1.1 +/- 0.2; 1.7 +/- 0.8; 0.4 +/- 0.1) was found to be extremely low compared with the 2.8-9% range we found for plasma LDL-protein, while the amount of LDL-lipid associated carbohydrate from hepatoma LDL was similar to that we found in plasma LDL. Furthermore, desialation of hepatoma cell-secreted LDL with neuraminidase did not normalize the negative charge to that of neuraminidase-treated plasma LDL. Western blots of thrombin proteolytic fragments indicated that, in addition to the T1-T4 fragments seen in plasma apolipoprotein B, apolipoprotein B of hepatoma-derived LDL produced four to five new fragments (T5-T9), suggesting increased exposure of proteolytic sites. Western blotting of the new fragments with antibodies specific for known apolipoprotein B sequences suggests that many of the new cleavage sites cluster in or near the putative LDL receptor recognition site.
Collapse
Affiliation(s)
- M La Belle
- Research Medicine and Radiation Biophysics Division, Lawrence Berkeley Laboratory, University of California, Berkeley 94720
| | | | | | | |
Collapse
|
36
|
Atherogenic lipoproteins found in the blood of patients with coronary atherosclerosis are desialylated low-density lipoproteins. Bull Exp Biol Med 1990. [DOI: 10.1007/bf00840076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
37
|
Tsunemitsu M, Ishikawa Y, Taniguchi T, Fukuzaki H. Heterogeneity of N-linked sugar chains of apolipoprotein B-100 in Watanabe heritable hyperlipidemic and fasting rabbits. ARTERIOSCLEROSIS (DALLAS, TEX.) 1990; 10:386-93. [PMID: 2344297 DOI: 10.1161/01.atv.10.3.386] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have elucidated the structures of N-linked sugar chains of human apolipoprotein (apo) B-100 (Arch Biochem Biophys 1989; 273:197-205). To investigate the role of the carbohydrate moieties of apolipoprotein B-100, we determined the structures of the N-linked sugar chains of apo B-100 purified from low density lipoprotein (LDL) of a Watanabe heritable hyperlipidemic (WHHL) rabbit and compared them with those of fasting Japanese White rabbits. The N-linked oligosaccharides of apo B-100 were liberated by hydrozinolysis, followed by NaB3H4 reduction, and were fractionated by paper electrophoresis and Bio-Gel P-4 column chromatography. These consisted of one neutral fraction (N) and two acidic fractions (A1 and A2) in both WHHL and fasting rabbits. N contained high mannose type oligosaccharides consisting of Man5GlcNAc2 to Man9GlcNAc2. A1 and A2 contained monosialylated and disialylated biantennary complex type oligosaccharides, respectively. The molar ratios of N, A1, and A2 were 5:2:2 in the WHHL rabbit and 4:2:5 in fasting rabbits. The content of sialic acid residues in the WHHL rabbit was calculated to be 0.64 by taking the value of that in fasting rabbits as 1.0. These results show the heterogeneity of N-linked sugar chains of apo B-100 in WHHL and fasting rabbits and suggest the possibility that the characteristics of LDL in WHHL rabbits may be altered by making the surface charge more positive than in fasting rabbits.
Collapse
Affiliation(s)
- M Tsunemitsu
- First Department of Internal Medicine, Kobe University School of Medicine, Japan
| | | | | | | |
Collapse
|
38
|
Taniguchi T, Ishikawa Y, Tsunemitsu M, Fukuzaki H. The structures of the asparagine-linked sugar chains of human apolipoprotein B-100. Arch Biochem Biophys 1989; 273:197-205. [PMID: 2757392 DOI: 10.1016/0003-9861(89)90179-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The asparagine-linked sugar chains of human apolipoprotein B-100 were liberated from the polypeptide portion by hydrazinolysis followed by N-acetylation and NaB3H4 reduction. Their structures were elucidated by sequential exoglycosidase digestion in combination with methylation analysis after fractionation by paper electrophoresis and gel permeation chromatography. One neutral and two acidic fractions were obtained by paper electrophoresis in a molar ratio of 7:8:5. The neutral fraction contained high-mannose type oligosaccharides consisting of Man5GlcNAc2 to Man9GlcNAc2. The acidic fractions contained monosialylated and disialylated biantennary complex type oligosaccharides. As minor components in the monosialylated fraction, biantennary complex-type oligosaccharides which were absent one terminal galactose residue, monoantennary complex type, and hybrid type oligosaccharides were detected. Apolipoprotein B-100 was calculated to contain 5-6 mol of high-mannose type and 8-10 mol of complex type oligosaccharides per mole protein.
Collapse
Affiliation(s)
- T Taniguchi
- First Department of Internal Medicine, Kobe University School of Medicine, Japan
| | | | | | | |
Collapse
|
39
|
Orekhov AN, Tertov VV, Mukhin DN, Mikhailenko IA. Modification of low density lipoprotein by desialylation causes lipid accumulation in cultured cells: discovery of desialylated lipoprotein with altered cellular metabolism in the blood of atherosclerotic patients. Biochem Biophys Res Commun 1989; 162:206-11. [PMID: 2751649 DOI: 10.1016/0006-291x(89)91982-7] [Citation(s) in RCA: 108] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Low density lipoprotein (LDL) isolated from the blood of healthy donors was partially desialylated by incubating the lipoprotein with sialidase (neuraminidase). The addition of LDL treated with neuraminidase to cultured human aortic intimal cells of smooth muscle origin caused a substantial increase in intracellular cholesteryl esters, free cholesterol and triglycerides. Cultured cells took up and degraded desialylated LDL much more effectively than untreated (native) LDL. LDL were also isolated from an atherogenic blood plasma of patients with coronary artery disease, i.e. the plasma capable of inducing the accumulation of lipids in cultured cells. Patients' LDL, similarly to the mother plasma, were atherogenic, i.e. stimulated the accumulation of intracellular lipids. LDL isolated from nonatherogenic plasma of healthy donors proved to be nonatherogenic. Atherogenic patients' LDL had a 2- to 5-fold lower level of sialic acid as compared with nonatherogenic LDL of healthy donors. The uptake and degradation of atherogenic patients' LDL were much more effective than in the case of nonatherogenic LDL of healthy donors. We assume that atherogenic properties of LDL obtained from patients' blood plasma are explained exactly by a low sialic acid content.
Collapse
Affiliation(s)
- A N Orekhov
- Institute of Experimental Cardiology, USSR Cardiology Research Center, Moscow, Russia
| | | | | | | |
Collapse
|
40
|
Sprague EA, Moser M, Edwards EH, Schwartz CJ. Stimulation of receptor-mediated low density lipoprotein endocytosis in neuraminidase-treated cultured bovine aortic endothelial cells. J Cell Physiol 1988; 137:251-62. [PMID: 3192617 DOI: 10.1002/jcp.1041370207] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Sialic acids, occupying a terminal position in cell surface glycoconjugates, are major contributors to the net negative charge of the vascular endothelial cell surface. As integral membrane glycoproteins, LDL receptors also bear terminal sialic acid residues. Pretreatment of near-confluent, cultured bovine aortic endothelial cells (BAEC) with neuraminidase (50 mU/ml, 30 min, 37 degrees C) stimulated a significant increase in receptor-mediated 125I-LDL internalization and degradation relative to PBS-treated control cells. Binding studies at 4 degrees C revealed an increased affinity of LDL receptor sites on neuraminidase-treated cells compared to control BAEC (6.9 vs. 16.2 nM/10(6) BAEC) without a change in receptor site number. This enhanced LDL endocytosis in neuraminidase-treated cells was dependent upon the enzymatic activity of the neuraminidase and the removal of sialic acid from the cell surface. Furthermore, enhanced endocytosis due to enzymatic alteration of the 125I-LDL molecules was excluded. In contrast to BAEC, neuraminidase pretreatment of LDL receptor-upregulated cultured normal human fibroblasts resulted in an inhibition of 125I-LDL binding, internalization, and degradation. Specifically, a significant inhibition in 125I-LDL internalization was observed at 1 hr after neuraminidase treatment, which was associated with a decrease in the number of cell surface LDL receptor sites. Like BAEC, neuraminidase pretreatment of human umbilical vein endothelial cells resulted in enhanced receptor-mediated 125I-LDL endocytosis. These results indicate that sialic acid associated with either adjacent endothelial cell surface molecules or the endothelial LDL receptor itself may modulate LDL receptor-mediated endocytosis and suggest that this regulatory mechanism may be of particular importance to endothelial cells.
Collapse
Affiliation(s)
- E A Sprague
- Department of Pathology, University of Texas Health Science Center, San Antonio 78284
| | | | | | | |
Collapse
|
41
|
Herak JN, Udovicić L, Pifat G, Brnjas-Kraljević J, Jürgens G, Holasek A. An ESR study of the effect of an electrostatic field on binding of divalent cations to the surface of serum low-density lipoproteins. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 876:200-9. [PMID: 3006783 DOI: 10.1016/0005-2760(86)90275-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The ESR technique has been used to study binding of Mn(II) ions to low-density lipoprotein (LDL) in solutions of various electrolyte ionic strengths. A model of the binding has been proposed which describes all the observations in electrolytes of ten different concentrations in terms of two types of binding sites and two corresponding sets of intrinsic binding parameters (n1 = 8, Kd1 = 1.31 X 10(-3) mol X l-1 and n2 = 170, Kd2 = 5.71 X 10(-2) mol X l-1). These parameters, together with the values of the potential (phi 0) responsible for binding of the ions to specific charged sites on the surface, reproduce the observed binding curves well in all the systems studied. The phi 0 values are obtained as an appropriate solution of the Poisson-Boltzmann equation.
Collapse
|
42
|
Prokazova NV, Mikhailenko IA, Preobrazhensky SN, Ivanov VO, Pokrovsky SN, Timofeeva NG, Martinova MA, Repin VS, Bergelson LD. Interaction of gangliosides with plasma low density lipoproteins. Glycoconj J 1986. [DOI: 10.1007/bf01051777] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
43
|
Characterisation of heterologous and homologous low-density lipoprotein binding to apolipoprotein B,E receptors on porcine adrenal cortex membranes: enhanced binding of trypsin-modified human low-density lipoprotein. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 835:258-72. [PMID: 2988638 DOI: 10.1016/0005-2760(85)90281-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The characteristics of the binding of homologous and heterologous (human) LDL to membrane preparations from porcine adrenal cortex have been determined. The membranes displayed a single class of high-affinity, saturable binding site for both 125I-labelled porcine and human LDL, which was dependent on divalent cations, in addition to a low-affinity, non-saturable component(s). Porcine LDL displaced both 125I-labelled porcine and 125I-labelled human LDLs from the high-affinity binding site more effectively than human LDL, reflecting the lower Kd, (13.2 micrograms/ml) for porcine than human (Kd 19.2 micrograms/ml) LDL. These values are comparable to those obtained for half-maximal binding of human and bovine LDLs in a bovine adrenocortical membrane system (Kovanen, P.T., Basu, S.K., Goldstein, J.L. and Brown, M.S. (1979) Endocrinology 104, 610-616). Tryptic modification of porcine LDL (T-LDL) diminished its ability to compete with 125I-labelled native LDL for the high-affinity binding site; in contrast, 125I-labelled porcine T-LDL showed an elevated receptor affinity (Kd 9.7 micrograms/ml) and was more efficiently displaced by its unlabelled counterpart than by native porcine LDL. Tryptic treatment of human LDL similarly increased its binding affinity (Kd 8.3 micrograms/ml), although in this case, the unlabelled T-LDL displaced not only 125I-labelled human T-LDL but also 125I-labelled human LDL from the high-affinity site more effectively than native LDL. We conclude that (i) porcine adrenocortical membranes possess binding sites specific for LDL and resembling the apolipoprotein B,E receptors already demonstrated in murine, bovine and human adrenal cortex; (ii) tryptic modification of porcine LDL may remove or destroy segments of apolipoprotein B100 which contribute to receptor recognition sites on the surface of the particle; (iii) trypsinised porcine LDL may interact with the membrane binding site by a mechanism differing from that by which native LDL binds, and (iv) trypsinisation of human LDL may cleave or remove species-specific segments of the B100 protein at or close to the receptor recognition site(s) on the particle, thus decreasing structural differences between porcine and human LDL, and thereby enhancing its binding affinity for the porcine receptor.
Collapse
|
44
|
Subbaiah PV, Chen CH, Bagdade JD, Albers JJ. Role of low density lipoprotein in the activation of plasma lysolecithin acyltransferase activity. Effect of chemical and enzymatic modifications of the lipoprotein on enzyme activity. Atherosclerosis 1985; 54:99-110. [PMID: 3922384 DOI: 10.1016/0021-9150(85)90157-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The effect of various chemical and enzymatic modifications of low density lipoprotein (LDL) on its ability to activate the isolated human plasma lysolecithin acyltransferase (LAT) was studied. Removal of all lipids from LDL resulted in the complete loss of LAT activation. Removal of only neutral lipids by extraction with heptane retained up to 50% of the original activity, which was not increased further by reconstitution of the LDL with the extracted lipids. Hydrolysis of the diacylphosphoglycerides of the LDL with phospholipases resulted in complete loss of LAT activation which was partially restored by the addition of egg lecithin. Hydrolysis of more than 4% of LDL protein by trypsin led to a linear decrease in activity with complete loss of activity occurring when about 25% of the LDL protein is hydrolyzed. Modification of the arginine groups of LDL reversibly inhibited the activation of LAT. Modification of lysine residues of LDL by acetylation, acetoacetylation or succinylation also abolished its ability to activate lysolecithin acylation.
Collapse
|
45
|
Calvert GD, Abbey M. Plasma lipoproteins, apolipoproteins, and proteins concerned with lipid metabolism. Adv Clin Chem 1985; 24:217-98. [PMID: 3911751 DOI: 10.1016/s0065-2423(08)60274-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
46
|
Mahley RW, Innerarity TL. Lipoprotein receptors and cholesterol homeostasis. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 737:197-222. [PMID: 6303423 DOI: 10.1016/0304-4157(83)90001-1] [Citation(s) in RCA: 581] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
47
|
Chapman MJ, Millet A, Lagrange D, Goldstein S, Blouquit Y, Taylaur CE, Mills GL. The surface-exposed, trypsin-accessible segments of apolipoprotein B in the low-density lipoprotein of human serum. Fractionation and characterisation of the liberated peptides. EUROPEAN JOURNAL OF BIOCHEMISTRY 1982; 125:479-89. [PMID: 7117246 DOI: 10.1111/j.1432-1033.1982.tb06708.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
48
|
Herak JN, Pifat G, Brnjas-Kraljević J, Jürgens G. Adsorption of Mn(II) ions to human low density lipoproteins. Magnetic resonance studies. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 710:324-31. [PMID: 7074120 DOI: 10.1016/0005-2760(82)90115-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Mn(II) ions were used to study ion-binding properties of human low density lipoproteins (LDL). From the intensity of the EPR lines corresponding to the unbound Mn(II) ions the percentage of the ions bound to LDL is determined. By the titration of LDL with Mn(II) the binding parameters, dissociation constant, Kd, and the number of binding sites, n, could be derived. It has been found that there are at least two types of binding site on the LDL surface: 'strong' sites characterized by n = 6, Kd =1 x 5 x 10(-5)M x 1(-1), and 'weak' sites characterized by n = 145 and Kd = 6.6 x 10(-3)M x l(-1) for the sample in 0.01 M Tris-HCl buffer at 10 degrees C. At very low Mn(II) concentrations binding to the 'strong' sites exhibits a cooperative behaviour. In the 0.1 M buffer the 'strong' sites are almost completely occupied or blocked by the monovalent buffer cations. The number of the 'weak' sites remains unaltered and Kd is decreased slightly (Kd = 4.9 x 10(-3)M x (-1)). The location, chemical nature and the structural and functional relevance of the binding sites are discussed.
Collapse
|
49
|
Fless GM, Kirchhausen T, Fischer-Dzoga K, Wissler RW, Scanu AM. Serum low density lipoproteins with mitogenic effect on cultured aortic smooth muscle cells. Atherosclerosis 1982; 41:171-83. [PMID: 7066069 DOI: 10.1016/0021-9150(82)90183-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Low density lipoprotein (LDL) subspecies of different size and lipid mass were isolated by density gradient ultracentrifugation from the serum of male rhesus monkeys (Macaca mulatta) fed both a low fat, low cholesterol commercial primate ration, and cholesterol-supplemented high-fat diets, as well as from the serum of human donors. The mitogenic effect of these lipoproteins was examined using primary cultures of rhesus aortic smooth muscle cells. It was observed that the smaller LDL (molecular weight 2.7 X 10(6) from normolipidemic monkeys and a small LDL (molecular weight 2.6 X 10(6) occurring in some normal human subjects exhibited no mitogenic action. In turn, the larger LDL subspecies (molecular weight greater than 3.0 X 10(6), and buoyant density less than 1.030 g/ml), whether from normolipidemic or hyperlipidemic monkeys, or from some normal human subjects, had a marked proliferative action. The results indicate that both hyperlipidemic and normal sera (both human and rhesus) contain mitogenic LDL species although in different amounts. LDL-III, the rhesus equivalent of human Lp(a) was not mitogenic despite its similarity on size and lipid composition to the stimulating particles. However, on the removal of most of its large sialic acid moiety, a clear mitogenic action was observed. The mechanisms responsible for the proliferative effect are unclear and may involve LDL mass, lipid composition, and surface charge although other speculations cannot at present be ruled out. Furthermore, since the small LDL subspecies of either rhesus or human origin were nonmitogenic and similar in mass to the LDL found in calf serum, the mitogenic response of the smooth muscle cells to large LDLs may depend on their early conditioning with the LDL of calf serum.
Collapse
|
50
|
|