1
|
Okumura T, Joshita S, Sugiura A, Ota M, Umemura T. Quantitative changes of lipoprotein(a) in chronic hepatitis C patients achieving a sustained virological response by direct-acting antivirals. Clin Res Hepatol Gastroenterol 2022; 46:102011. [PMID: 36031100 DOI: 10.1016/j.clinre.2022.102011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/16/2022] [Accepted: 08/24/2022] [Indexed: 02/04/2023]
Affiliation(s)
- Taiki Okumura
- Department of Medicine, Division of Gastroenterology and Hepatology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Satoru Joshita
- Department of Medicine, Division of Gastroenterology and Hepatology, Shinshu University School of Medicine, Matsumoto, Japan; Department of Health Promotion Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
| | - Ayumi Sugiura
- Department of Medicine, Division of Gastroenterology and Hepatology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Masao Ota
- Department of Medicine, Division of Gastroenterology and Hepatology, Shinshu University School of Medicine, Matsumoto, Japan; Department of Health Promotion Medicine, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takeji Umemura
- Department of Medicine, Division of Gastroenterology and Hepatology, Shinshu University School of Medicine, Matsumoto, Japan; Department of Health Promotion Medicine, Shinshu University School of Medicine, Matsumoto, Japan; Department of Advanced Therapeutic Endoscopy, Shinshu University School of Medicine, Matsumoto, Japan; Consultation Center for Liver Diseases, Shinshu University Hospital, Matsumoto, Japan
| |
Collapse
|
2
|
Nordestgaard BG, Langsted A. Lipoprotein (a) as a cause of cardiovascular disease: insights from epidemiology, genetics, and biology. J Lipid Res 2016; 57:1953-1975. [PMID: 27677946 DOI: 10.1194/jlr.r071233] [Citation(s) in RCA: 334] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Indexed: 12/24/2022] Open
Abstract
Human epidemiologic and genetic evidence using the Mendelian randomization approach in large-scale studies now strongly supports that elevated lipoprotein (a) [Lp(a)] is a causal risk factor for cardiovascular disease, that is, for myocardial infarction, atherosclerotic stenosis, and aortic valve stenosis. The Mendelian randomization approach used to infer causality is generally not affected by confounding and reverse causation, the major problems of observational epidemiology. This approach is particularly valuable to study causality of Lp(a), as single genetic variants exist that explain 27-28% of all variation in plasma Lp(a). The most important genetic variant likely is the kringle IV type 2 (KIV-2) copy number variant, as the apo(a) product of this variant influences fibrinolysis and thereby thrombosis, as opposed to the Lp(a) particle per se. We speculate that the physiological role of KIV-2 in Lp(a) could be through wound healing during childbirth, infections, and injury, a role that, in addition, could lead to more blood clots promoting stenosis of arteries and the aortic valve, and myocardial infarction. Randomized placebo-controlled trials of Lp(a) reduction in individuals with very high concentrations to reduce cardiovascular disease are awaited. Recent genetic evidence documents elevated Lp(a) as a cause of myocardial infarction, atherosclerotic stenosis, and aortic valve stenosis.
Collapse
Affiliation(s)
- Børge G Nordestgaard
- Department of Clinical Biochemistry and Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark; and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anne Langsted
- Department of Clinical Biochemistry and Copenhagen General Population Study, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark; and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
3
|
Carulli C, Innocenti M, Brandi ML. Bone vascularization in normal and disease conditions. Front Endocrinol (Lausanne) 2013; 4:106. [PMID: 23986744 PMCID: PMC3752619 DOI: 10.3389/fendo.2013.00106] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 08/06/2013] [Indexed: 01/14/2023] Open
Abstract
Bone vasculature is essential for many processes, such as skeletal development and growth, bone modeling and remodeling, and healing processes. Endothelium is an integral part of bone tissue, expressing a physiological paracrine function via growth factors and chemokines release, and interacting with several cellular lines. Alterations of the complex biochemical interactions between vasculature and bone cells may lead to various clinical manifestations. Two different types of pathologies result: a defect or an excess of bone vasculature or endothelium metabolism. Starting from the molecular basis of the interactions between endothelial and bone cells, the Authors present an overview of the recent acquisitions in the physiopathology of the most important clinical patterns, and the modern therapeutic strategies for their treatments.
Collapse
Affiliation(s)
- Christian Carulli
- Department of Surgery and Translational Medicine, University of Florence, Florence, Italy
| | - Massimo Innocenti
- Department of Surgery and Translational Medicine, University of Florence, Florence, Italy
| | - Maria Luisa Brandi
- Department of Surgery and Translational Medicine, University of Florence, Florence, Italy
- *Correspondence: Maria Luisa Brandi, Department of Surgery and Translational Medicine, University of Florence, Viale Pieraccini, 650139 Florence, Italy e-mail:
| |
Collapse
|
4
|
Lippi G, Franchini M, Targher G. Screening and therapeutic management of lipoprotein(a) excess: review of the epidemiological evidence, guidelines and recommendations. Clin Chim Acta 2011; 412:797-801. [PMID: 21256836 DOI: 10.1016/j.cca.2011.01.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 01/10/2011] [Accepted: 01/14/2011] [Indexed: 11/24/2022]
Abstract
Lipoprotein(a) (Lp(a)) is a low density lipoprotein-like particle in which apolipoprotein B100 is covalently linked to the unique apolipoprotein(a). There is a mounting body of evidence suggesting a role of Lp(a) in the development and progression of several vascular diseases, such as coronary heart disease, ischemic stroke, abdominal aortic aneurysm and venous thromboembolism, so that prominent scientific societies have recently endorsed guidelines and recommendations that increasingly encourage the screening and the therapeutic management of Lp(a) excess. In this article, we review the epidemiologic evidence, guidelines and recommendations concerning the relationship between increased plasma Lp(a) levels and risk of cardiovascular disease or venous thromboembolism by systematically retrieving the most relevant articles from electronic databases. Although uncertainty still remains regarding the opportunity to screen for hyperlipoproteinemia(a), it seems inopportune as yet to measure plasma Lp(a) levels in asymptomatic persons, while its measurement might be of clinical significance in selected categories of patients at intermediate or high cardiovascular risk. The measurement of Lp(a) should be performed by using immunometric, harmonized and size-insensitive techniques and results reported in total lipoprotein mass rather than in traditional units. It is uncertain if Lp(a) genotyping or phenotyping add any additional information for the cardiovascular disease risk stratification. Although the optimal therapeutic management of Lp(a) excess is still controversial, a general agreement exists that very high Lp(a) levels should be lowered in patients with multiple cardiovascular risk factors, preferably with nicotinic acid therapy (e.g., 1.0-3.0 g/day).
Collapse
Affiliation(s)
- Giuseppe Lippi
- U.O. Diagnostica Ematochimica, Dipartimento di Patologia e Medicina di Laboratorio, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
| | | | | |
Collapse
|
5
|
Apolipoprotein(a) Isoforms and the Risk of Vascular Disease. J Am Coll Cardiol 2010; 55:2160-7. [DOI: 10.1016/j.jacc.2009.10.080] [Citation(s) in RCA: 234] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 10/26/2009] [Accepted: 10/26/2009] [Indexed: 11/23/2022]
|
6
|
Bahri R, Esteban E, Moral P, Hassine M, Ben Hamda K, Chaabani H. Apolipoprotein gene polymorphisms and plasma levels in healthy Tunisians and patients with coronary artery disease. Lipids Health Dis 2008; 7:46. [PMID: 19014618 PMCID: PMC2615423 DOI: 10.1186/1476-511x-7-46] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Accepted: 11/17/2008] [Indexed: 12/30/2022] Open
Abstract
Aim To analyze apolipoprotein gene polymorphisms in the Tunisian population and to check the relation of these polymorphisms and homocysteine, lipid and apolipoprotein levels to the coronary artery disease (CAD). Methods In healthy blood donors and in patients with CAD complicated by myocardial infarction (MI) four apolipoprotein gene polymorphisms [APO (a) PNR, APO E, APO CI and APO CII] were determined and plasma levels of total homocysteine, total cholesterol (TC), triglycerides (TG), HDL-cholesterol (HLD-C) and apolipoproteins (apo A-I, Apo B, Apo E) were measured. Results Analysis of the four apolipoprotein gene polymorphisms shows a relative genetic homogeneity between Tunisian population and those on the other side of Mediterranean basin. Compared to controls, CAD patients have significantly higher main concentrations of TC, TG, LDL-C, apo B and homocysteine, and significantly lower ones of HDL-C, apo A-I and apo E. The four apolipoprotein gene polymorphisms have not showed any significant differences between patients and controls. However, the APO E4 allele appears to be associated to the severity of CAD and to high levels of atherogenic parameters and low level of apo E, which has very likely an anti-atherogenic role. Conclusion Although APO (a) PNR, APO CI and APO CII genes are analyzed in only few populations, they show a frequency distribution, which is not at variance with that of APO E gene and other widely studied genetic markers. In the Tunisian population the APO E 4 appears to be only indirectly involved in the severity of CAD. In the routine practice, in addition of classic parameters, it will be useful to measure the concentration of apo E and that of Homocysteine and if possible to determine the APO E gene polymorphism.
Collapse
Affiliation(s)
- Raoudha Bahri
- Laboratoire de Génétique Humaine, Faculté de Pharmacie de Monastir, Université de Monastir 5000 Monastir, Tunisia.
| | | | | | | | | | | |
Collapse
|
7
|
Rubin J, Kim HJ, Pearson TA, Holleran S, Berglund L, Ramakrishnan R. The apolipoprotein(a) gene: linkage disequilibria at three loci differs in African Americans and Caucasians. Atherosclerosis 2008; 201:138-47. [PMID: 18304554 DOI: 10.1016/j.atherosclerosis.2008.01.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 12/18/2007] [Accepted: 01/15/2008] [Indexed: 10/22/2022]
Abstract
Lipoprotein(a) (Lp(a)) is an independent, genetically regulated cardiovascular risk factor. Lp(a) plasma levels are largely determined by the apolipoprotein(a) (apo(a)) component, and differ across ethnicity. Although a number of polymorphisms in the apo(a) gene have been identified, apo(a) genetic regulation is not fully understood. To study the relation between apo(a) gene variants, we constructed haplotypes and assessed linkage equilibrium in African Americans and Caucasians for three widely studied apo(a) gene polymorphisms (apo(a) size, +93 C/T and pentanucleotide repeat region (PNR)). Apo(a) size allele frequency distributions were different across ethnicity (p<0.01). For African Americans, PNR frequencies were similar across apo(a) sizes, suggesting linkage equilibrium. For Caucasians, the PNR and the PNR-C/T haplotype frequencies differed for large and small apo(a), with the T and PNR 9 alleles associated with large apo(a) size (p<0.0002); also, the PNR 9 allele was more common on a T allele, while PNR 8 was more common on a C allele. On a C allele background, small PNR alleles were more common and the PNR 10 allele less common among African Americans than Caucasians (p<0.001). The ethnic difference in apo(a) size distribution remained controlling for C/T and PNR alleles (p=0.023). In conclusion, allele and haplotype frequencies and the nature of the linkage disequilibrium differed between African Americans and Caucasians at three apo(a) gene polymorphisms.
Collapse
Affiliation(s)
- Jill Rubin
- Departments of Medicine, Columbia University, New York, NY, United States
| | | | | | | | | | | |
Collapse
|
8
|
Zídková K, Zlatohlávek L, Ceska R. Variability in apo(a) gene regulatory sequences, compound genotypes, and association with Lp(a) plasma levels. Clin Biochem 2007; 40:802-5. [PMID: 17462619 DOI: 10.1016/j.clinbiochem.2007.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 03/14/2007] [Accepted: 03/17/2007] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Lipoprotein(a) is an independent risk factor of atherosclerosis. DESIGN AND METHODS We assigned frequencies of six polymorphic sites from apo(a) gene transcription control regions, linkage disequilibrium, and 5-polymorphic compound genotypes association with Lp(a) levels. RESULTS Significant linkage disequilibrium between polymorphic sites was detected. Compound genotypes were significantly associated with Lp(a) levels (P<0.0001). Major 5-polymorphic genotypes were distributed in a broad range of concentrations. CONCLUSIONS Major 5-polymorphic compound genotypes are not associated with restricted range of Lp(a) levels.
Collapse
Affiliation(s)
- Katerina Zídková
- 3rd Medical Department, 1st Faculty of Medicine and General Teaching Hospital, Charles University, Prague, Czech Republic.
| | | | | |
Collapse
|
9
|
Zídková K, Kebrdlová V, Zlatohlávek L, Ceska R. Detection of variability in apo(a) gene transcription regulatory sequences using the DGGE method. Clin Chim Acta 2006; 376:77-81. [PMID: 16916503 DOI: 10.1016/j.cca.2006.07.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/17/2006] [Accepted: 07/17/2006] [Indexed: 11/27/2022]
Abstract
BACKGROUND Increased lipoprotein(a), Lp(a), concentration is an independent risk factor for premature atherosclerosis. Apolipoprotein(a), apo(a), determines properties of the lipoprotein and its production rate is the limiting step in Lp(a) particle formation. METHODS Subjects covering the whole range of Lp(a) concentration were separated into quintiles. A randomly chosen sample from each quintile was derived, there being a total number of 713 individuals. The DGGE method was used to scan the known transcription regulatory regions of apo(a) gene (promoter; DHII and DHIII enhancers) for variability and its distribution across quintiles. RESULTS Besides 5 previously reported nucleotide substitutions (+121 G>A; +93 C>T; -1712 G>T; -1617 C>A; -1230 A>G) 16 unreported rare sequence variants were detected. All polymorphic variants were distributed throughout the quintiles with several significant differences. The novel +62 C variant was found only among individuals with Lp(a) levels over 16 mg/dl. CONCLUSION The apo(a) gene transcription regulatory regions were not revealed to be extremely polymorphic. However, we should consider a combined effect of all polymorphic sites from the whole apo(a) gene locus, including the apo(a) gene length polymorphism, when dealing with high population variability of Lp(a) levels.
Collapse
Affiliation(s)
- Katerina Zídková
- 3rd Medical Department, 1st Faculty of Medicine and General Teaching Hospital, Charles University in Prague, Prague 12808, Czech Republic.
| | | | | | | |
Collapse
|
10
|
Rubin J, Kim HJ, Pearson TA, Holleran S, Ramakrishnan R, Berglund L. Apo[a] size and PNR explain African American-Caucasian differences in allele-specific apo[a] levels for small but not large apo[a]. J Lipid Res 2006; 47:982-9. [PMID: 16495513 DOI: 10.1194/jlr.m500359-jlr200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Apolipoprotein [a] (apo[a]) gene size is a major predictor of lipoprotein [a] level. To determine genetic predictors of allele-specific apo[a] levels beyond gene size, we evaluated the upstream C/T and pentanucleotide repeat (PNR) polymorphisms. We determined apo[a] sizes, allele-specific apo[a] levels, and C/T and PNR in 215 Caucasians and 139 African Americans. For Caucasians, apo[a] size affected allele-specific levels substantially greater in subjects with apo[a] < 24 K4; for African Americans, the size effect was smaller than in Caucasians, <24 K4, but did not decrease at higher repeats. In both groups, the level decreased with increasing size of the other allele. Controlling for apo[a] sizes, PNR decreased allele-specific apo[a] levels in Caucasians with increasing PNR > 8. In a multiple regression model, apo[a] allele size and size and expression of the other apo[a] allele (and PNR > 8 for Caucasians) significantly predicted allele-specific apo[a] levels. For a common PNR 8 allele, predicted values were similar in the two ethnicities for small size apo[a]. Allele-specific apo[a] levels were influenced by the other allele size and expression. Observed differences between Caucasians and African Americans in allele-specific apo[a] levels were explained for small apo[a] sizes by the other allele size and PNR; the ethnicity differences remain unexplained for larger sizes.
Collapse
Affiliation(s)
- Jill Rubin
- Department of Medicine, Columbia University, New York, NY, USA
| | | | | | | | | | | |
Collapse
|
11
|
Széplaki G, Varga L, Valentin S, Kleiber M, Karádi I, Romics L, Füst G, Farkas H. Adverse effects of danazol prophylaxis on the lipid profiles of patients with hereditary angioedema. J Allergy Clin Immunol 2005; 115:864-9. [PMID: 15806011 DOI: 10.1016/j.jaci.2004.12.1130] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Hereditary angioedema (HAE) is a rare disorder caused by the deficiency of the C1-inhibitor gene (C1INH) . Patients experience recurrent bouts of edema, which can occur in almost any region of the body. As regards the treatment of the disease, danazol (an attenuated androgen) is used, among other agents, for long-term prophylaxis. OBJECTIVE The aim of this study was to investigate the possible adverse effects of danazol on serum lipid profile, as well as to ascertain whether danazol treatment is associated with an increased risk of atherosclerosis. METHODS Serum concentrations of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, apolipoprotein A-I, apolipoprotein B-100, and lipoprotein(a) were compared between danazol-treated patients with HAE and 2 control groups (ie, patients who did not receive long-term danazol prophylaxis and untreated healthy subjects). RESULTS Serum concentrations of HDL ( P = .0002 and P < .0001) and apolipoprotein A-I ( P = .0015 and P < .0001) were significantly lower, whereas LDL ( P = .0129 and P = .0127) and apolipoprotein B-100 ( P = .0456 and P = .0013) were higher in the danazol-treated patients compared with the 2 control groups, respectively. No significant difference was found in total cholesterol, triglyceride, or lipoprotein(a) levels. Patients who received danazol had an 11.6 (95% CI, 2.7-49.7) times higher risk for abnormally low HDL levels and a 4.4 (95% CI, 1.2-16.0) times lower risk for high LDL concentrations. CONCLUSIONS Our findings indicate that the long-term use of danazol is associated with an increased risk for early atherosclerosis in patients with HAE. Consequently, monitoring of HDL and LDL levels at regular intervals is recommended during follow-up.
Collapse
Affiliation(s)
- Gábor Széplaki
- Third Department of Internal Medicine, Faculty of Medicine, Semmelweis University, Budapest, Kútvölgyi ut 4, H-1125 Budapest, Hungary
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
Lipoprotein (a) [Lp(a)], is present only in humans, Old World nonhuman primates, and the European hedgehog. Lp(a) has many properties in common with low-density lipoprotein (LDL) but contains a unique protein, apo(a), which is structurally different from other apolipoproteins. The size of the apo(a) gene is highly variable, resulting in the protein molecular weight ranging from 300 to 800 kDa; this large variation may be caused by neutral evolution in the absence of any selection advantage. Apo(a) influences to a major extent metabolic and physicochemical properties of Lp(a), and the size polymorphism of the apo(a) gene contributes to the pronounced heterogeneity of Lp(a). There is an inverse relationship between apo(a) size and Lp(a) levels; however, this pattern is complex. For a given apo(a) size, there is a considerable variation in Lp(a) levels across individuals, underscoring the importance to assess allele-specific Lp(a) levels. Further, Lp(a) levels differ between populations, and blacks have generally higher levels than Asians and whites, adjusting for apo(a) sizes. In addition to the apo(a) size polymorphism, an upstream pentanucleotide repeat (TTTTA(n)) affects Lp(a) levels. Several meta-analyses have provided support for an association between Lp(a) and coronary artery disease, and the levels of Lp(a) carried in particles with smaller size apo(a) isoforms are associated with cardiovascular disease or with preclinical vascular changes. Further, there is an interaction between Lp(a) and other risk factors for cardiovascular disease. The physiological role of Lp(a) is unknown, although a majority of studies implicate Lp(a) as a risk factor.
Collapse
Affiliation(s)
- Lars Berglund
- Department of Medicine, University of California, Davis, UCD Medical Center, 4150 V Street, Suite G400, Sacramento, CA 95817, USA.
| | | |
Collapse
|
13
|
Baudhuin LM, Hartman SJ, O'Brien JF, Meissner I, Galen RS, Ward JN, Hogen SM, Branum EL, McConnell JP. Electrophoretic measurement of lipoprotein(a) cholesterol in plasma with and without ultracentrifugation: comparison with an immunoturbidimetric lipoprotein(a) method. Clin Biochem 2004; 37:481-8. [PMID: 15183296 DOI: 10.1016/j.clinbiochem.2004.02.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2003] [Revised: 01/30/2004] [Accepted: 02/03/2004] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Elevated plasma lipoprotein(a) [Lp(a)] is a significant risk factor for vascular disease. Standardization of Lp(a) mass measurement is complicated by the heterogeneity of apolipoprotein(a) [apo(a)]. We investigated whether Lp(a) cholesterol measurement, which is not influenced by apo(a) size, is a viable alternative to measuring Lp(a) mass. DESIGN AND METHODS Plasma Lp(a) cholesterol was measured electrophoretically, with and without ultracentrifugation, and results were compared to each other and to immunoturbidimetrically measured Lp(a) mass in 470 subjects. RESULTS Ultracentrifuged and whole plasma Lp(a) cholesterol levels demonstrated high correlation (R = 0.964). All samples with detectable (>/=2.0 mg/dl) Lp(a) cholesterol had Lp(a) mass >30 mg/dl (the clinically relevant cutpoint), while 59 samples with Lp(a) mass >30 mg/dl did not have detectable Lp(a) cholesterol. CONCLUSIONS Lp(a) cholesterol can be measured in whole plasma without interference from VLDL lipoproteins. The relative clinical merits of measuring Lp(a) cholesterol vs. Lp(a) mass or both in combination deserves investigation.
Collapse
Affiliation(s)
- Linnea M Baudhuin
- Department of Laboratory Medicine and Pathology, Mayo Clinic and Foundation, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Rifai N, Ma J, Sacks FM, Ridker PM, Hernandez WJL, Stampfer MJ, Marcovina SM. Apolipoprotein(a) size and lipoprotein(a) concentration and future risk of angina pectoris with evidence of severe coronary atherosclerosis in men: The Physicians' Health Study. Clin Chem 2004; 50:1364-71. [PMID: 15155542 DOI: 10.1373/clinchem.2003.030031] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The relationship of lipoprotein (a) [Lp(a)] concentrations with risk of coronary heart disease needs clarification, especially for threshold values for increased risk and for possible interactions with LDL-cholesterol concentrations and apolipoprotein (a) [apo(a)] size polymorphism. This study was designed to examine the ability of baseline Lp(a) concentration and apo(a) size to predict future severe angina pectoris in apparently healthy men. METHODS Baseline Lp(a) concentration and apo(a) size were determined in 195 men who subsequently developed angina and in 195 men who remained free of cardiovascular disease for 5 years. RESULTS Cases had higher median Lp(a) concentrations than did controls (30.6 vs 22.5 nmol/L; P = 0.02). Lp(a) concentration was predictive of angina [relative risk (RR) from lowest to highest quintiles: 1.0, 1.5, 1.0, 1.8, and 2.6; P for trend = 0.015]. The increased risk was approximately 4-fold (95% confidence interval, 1.4- to 11-fold) among men who had Lp(a) above the 95th percentile (>158 nmol/L). Men with Lp(a) concentrations in the highest quintile and LDL-cholesterol concentrations >1600 mg/L had a 12-fold increased risk (95% confidence interval, 1.5- to 43-fold). Small apo(a) size isoforms also significantly predicted risk of angina (RR for lowest quintile = 4.1; P for trend = 0.004). When the independent effect of Lp(a) concentration and apo(a) size was assessed by including them in the same multivariate model, only the association between apo(a) size and risk remained significant. CONCLUSIONS High Lp(a) predicts risk of angina, and the risk is substantially increased with high concomitant LDL-cholesterol. Small apo(a) size predicts angina with greater strength and independence than Lp(a) concentration.
Collapse
Affiliation(s)
- Nader Rifai
- Department of Laboratory Medicine, Children's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | | | | | | | |
Collapse
|
15
|
Sun L, Li Z, Zhang H, Ma A, Liao Y, Wang D, Zhao B, Zhu Z, Zhao J, Zhang Z, Wang W, Hui R. Pentanucleotide TTTTA repeat polymorphism of apolipoprotein(a) gene and plasma lipoprotein(a) are associated with ischemic and hemorrhagic stroke in Chinese: a multicenter case-control study in China. Stroke 2003; 34:1617-22. [PMID: 12791946 DOI: 10.1161/01.str.0000078370.12085.02] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND AND PURPOSE It is still inconclusive whether high plasma lipoprotein(a) [Lp(a)] level is a risk factor for stroke. Small sample size and different ethnic groups and methodologies might be contributors to the conflicts in study results. The purpose of the present study was to investigate the association between plasma Lp(a) levels, pentanucleotide TTTTA repeat (PNTR) polymorphism of the apolipoprotein(a) [apo(a)] gene, and Chinese stroke in a case-control study. METHODS We recruited 1825 cases with stroke (44.3% cerebral atherothrombosis, 28.3% lacunar infarction, and 27.3% intracerebral hemorrhage) and 1817 controls from 7 centers in China. Lp(a) concentrations were quantified by enzyme-linked immunosorbent assay. The PNTR polymorphism of the apo(a) gene was determined by polymerase chain reaction-polyacrylamide gel electrophoresis. Conditional multivariate logistic regression analysis was used to identify independent risk factors for stroke and its subtypes. RESULTS Lp(a) levels were significantly higher in cases than in controls (median, 28.5 versus 23.1 mg/dL; P<0.001), leading to a 1.97-fold (95% CI, 1.64 to 2.37) increase in risk for overall stroke, 2.0-fold (95% CI, 1.59 to 2.52) increase for atherothrombotic type, 2.05-fold increase (95% CI, 1.59 to 2.63) for lacunar type, and 1.64-fold increase (95% CI, 1.21 to 2.21) for hemorrhagic type. The number of PNTR negatively correlated with Lp(a) levels. Low-number repeats (sum of both alleles <16) of apo(a) PNTR were associated with both atherothrombotic stroke (odds ratio, 1.41; 95% CI, 1.04 to 1.91) and hemorrhagic stroke (odds ratio, 1.62; 95% CI, 1.09 to 2.37). CONCLUSIONS Our results indicate for the first time that low numbers of apo(a) PNTR and plasma Lp(a) levels are independently associated with both ischemic and hemorrhagic stroke in Chinese.
Collapse
Affiliation(s)
- Li Sun
- Sino-German Laboratory for Molecular Medicine and Center for Molecular Cardiology, Fuwai Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|