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Moraitis AG, Freeman LA, Shamburek RD, Wesley R, Wilson W, Grant CM, Price S, Demosky S, Thacker SG, Zarzour A, Hornung RL, Pucino F, Csako G, Yarboro C, McInnes IB, Kuroiwa T, Boumpas D, Rao VK, Illei GG, Remaley AT. Elevated interleukin-10: a new cause of dyslipidemia leading to severe HDL deficiency. J Clin Lipidol 2015; 9:81-90. [PMID: 25670364 PMCID: PMC5513489 DOI: 10.1016/j.jacl.2014.09.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 09/11/2014] [Accepted: 09/30/2014] [Indexed: 12/18/2022]
Abstract
BACKGROUND Low high-density lipoprotein cholesterol (HDL-C) is a risk factor for coronary artery disease. Investigating mechanisms underlying acquired severe HDL deficiency in noncritically ill patients ("disappearing HDL syndrome") could provide new insights into HDL metabolism. OBJECTIVE To determine the cause of low HDL-C in patients with severe acquired HDL deficiency. METHODS AND RESULTS Patients with intravascular large B-cell lymphoma (n = 2), diffuse large B-cell lymphoma (n = 1), and autoimmune lymphoproliferative syndrome (n = 1) presenting with markedly decreased HDL-C, low low-density lipoprotein cholesterol (LDL-C), and elevated triglycerides were identified. The abnormal lipoprotein profile returned to normal after therapy in all 4 patients. All patients were found to have markedly elevated serum interleukin-10 (IL-10) levels that also normalized after therapy. In a cohort of autoimmune lymphoproliferative syndrome patients (n = 93), IL-10 showed a strong inverse correlation with HDL-C (R(2) = 0.3720, P < .0001). A direct causal role for increased serum IL-10 in inducing the observed changes in lipoproteins was established in a randomized, placebo-controlled clinical trial of recombinant human IL-10 in psoriatic arthritis patients (n = 18). Within a week of initiating subcutaneous recombinant human IL-10 injections, HDL-C precipitously decreased to near-undetectable levels. LDL-C also decreased by more than 50% (P < .0001) and triglycerides increased by approximately 2-fold (P < .005). All values returned to baseline after discontinuing IL-10 therapy. CONCLUSION Increased IL-10 causes severe HDL-C deficiency, low LDL-C, and elevated triglycerides. IL-10 is thus a potent modulator of lipoprotein levels, a potential new biomarker for B-cell disorders, and a novel cause of disappearing HDL syndrome.
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Affiliation(s)
- Andreas G Moraitis
- Metabolism, Endocrinology & Diabetes, Endocrine Oncology Program, University of Michigan, Ann Arbor, MI, USA
| | - Lita A Freeman
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robert D Shamburek
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robert Wesley
- Hospital Epidemiology, National Institutes of Health, Bethesda, MD, USA
| | - Wyndham Wilson
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Cliona M Grant
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Susan Price
- ALPS Unit, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Stephen Demosky
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Seth G Thacker
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Abdalrahman Zarzour
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ronald L Hornung
- Clinical Services Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Frank Pucino
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Gyorgy Csako
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Cheryl Yarboro
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Iain B McInnes
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA; College of Medicine, Veterinary Medicine and Life Sciences, University of Glasgow, Glasgow, Scotland
| | - Takashi Kuroiwa
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Dimitrios Boumpas
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA; Medical School University of Athens, Affiliate Member IMBB, Heraklion and BRFAA Athens, Greece
| | - V Koneti Rao
- ALPS Unit, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Gabor G Illei
- National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alan T Remaley
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA; Department of Laboratory Medicine, National Institutes of Health, Bethesda, MD, USA.
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2
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El Khoury P, Plengpanich W, Frisdal E, Le Goff W, Khovidhunkit W, Guerin M. Improved plasma cholesterol efflux capacity from human macrophages in patients with hyperalphalipoproteinemia. Atherosclerosis 2014; 234:193-9. [PMID: 24674903 DOI: 10.1016/j.atherosclerosis.2014.02.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 02/20/2014] [Accepted: 02/27/2014] [Indexed: 11/25/2022]
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3
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Yokoyama S. Apolipoprotein-mediated cellular cholesterol efflux. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1392:1-15. [PMID: 9593801 DOI: 10.1016/s0005-2760(98)00032-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- S Yokoyama
- Department of Biochemistry I, Nagoya City University Medical School, Kawasumi 1, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan
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4
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Huang Y, Zhu Y, Langer C, Raabe M, Wu S, Wiesenhütter B, Seedorf U, Maeda N, Assmann G, von Eckardstein A. Effects of genotype and diet on cholesterol efflux into plasma and lipoproteins of normal, apolipoprotein A-I-, and apolipoprotein E-deficient mice. Arterioscler Thromb Vasc Biol 1997; 17:2010-9. [PMID: 9351366 DOI: 10.1161/01.atv.17.10.2010] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We investigated the contribution of apoE to cholesterol efflux into plasmas of normal, apoA-I-, and apoE-deficient mice, which were fed with chow- and cholesterol-rich diets. Plasmas of normal and apoA-I-deficient mice contain apoE in pre-beta-migrating VLDL as well as in HDL-like lipoproteins, which have either electrophoretic alpha- or gamma-mobilities. The latter particle resembled gamma-LpE in human plasma also by its mobility on nondenaturing two-dimensional electrophoresis. No apoE-containing lipoproteins were found in plasmas of apoE-deficient mice. When apoA-I- and apoE-deficient mice received both chow- and fat-rich diets, their plasmas released significantly less 3H-cholesterol from radiolabeled fibroblasts than did plasma of normal mice. Removal of apoE from plasmas of normal and apoA-I-deficient mice by anti-apoE immunoaffinity chromatography decreased their cholesterol efflux capacities (per 1 minute/per 1 hour) by 26%/40% (P = 0.0092/0.0007) and 30%/26% (P = 0.0092/0.0003), respectively. Net cholesterol efflux from fibroblasts into apoA-I-deficient plasma was 45% lower compared with plasma of normal mice. Incubation of fibroblasts with apoE-deficient plasma caused net influx of cholesterol. Prior addition of human apoE to or removal of apoB-containing lipoproteins from apoE-deficient plasma restored its ability to cause net cholesterol efflux to 50% of normal plasma. Some of the differences between cholesterol efflux into normal and apoE-deficient plasmas were attributable to the failure of apoE-deficient plasmas to take up cell-derived 3H-cholesterol into gamma-LpE. Compared with normal plasma, both apoA-I-deficient and apoE-deficient plasmas were significantly decreased in their activity to esterify cell-derived 3H-cholesterol. Anti-apoE chromatography decreased significantly cholesterol esterification in normal plasma and apoA-I-deficient plasma but not in apoE-deficient plasma. Taken together, the data provide evidence that apoE is an important contributor to reverse cholesterol transport, partially because of initial uptake of cell-derived cholesterol by gamma-LpE and partially because of the contribution of apoE-containing lipoproteins to esterification of cholesterol in plasma.
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Affiliation(s)
- Y Huang
- Institut für Arterioskleroseforschung, Universität Münster, Germany
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5
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Ng DS, Vezina C, Wolever TS, Kuksis A, Hegele RA, Connelly PW. Apolipoprotein A-I deficiency. Biochemical and metabolic characteristics. Arterioscler Thromb Vasc Biol 1995; 15:2157-64. [PMID: 7489237 DOI: 10.1161/01.atv.15.12.2157] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Familial HDL deficiencies are associated with variable susceptibility to premature coronary heart disease, but the mechanism underlying this association remains poorly understood. Three homozygotes with isolated complete apo A-I deficiency caused by an autosomal codominant apo A-I Q[-2]X mutation and one heterozygote developed coronary heart disease before age 40 years. We characterized the effects of this mutation on lipoprotein metabolism. LDL FC, phospholipid, and apo B were all significantly higher in homozygotes than in heterozygotes. The HDLs of the heterozygotes were apo A-I poor relative to apo A-II. Lecithin-cholesterol acyltransferase activity was 59% lower in homozygotes than in normal subjects or heterozygotes. Cholesteryl ester transfer activity was increased in a homozygote compared with a normolipidemic control subject. Postprandial lipid metabolism was studied in one homozygote and one heterozygote. Post-prandial TG response in the homozygote was significantly exaggerated, while residual plasma HDL level remained unaffected. The homozygote also had delayed clearance of retinyl ester, a marker of chylomicron remnant metabolism. Thus, homozygosity and heterozygosity for apo A-I Q[-2]X are associated with qualitative, as well as quantitative, disturbances in plasma HDLs, LDLs, lipid-modifying enzyme activities, and postprandial retinyl ester metabolism. The observed elevation of atherogenic lipoproteins and reduction in antiatherogenic lipoproteins in the affected members of the apo A-I Q[-2]X kindred are consistent with the primary deficiency in apo A-I having pleiotropic effects that markedly enhance susceptibility for coronary heart disease.
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Affiliation(s)
- D S Ng
- Department of Medicine, St Michael's Hospital, University of Toronto, Ontario, Canada
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6
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Tilly-Kiesi M, Zhang Q, Ehnholm S, Kahri J, Lahdenperä S, Ehnholm C, Taskinen MR. ApoA-IHelsinki (Lys107-->0) associated with reduced HDL cholesterol and LpA-I:A-II deficiency. Arterioscler Thromb Vasc Biol 1995; 15:1294-306. [PMID: 7670941 DOI: 10.1161/01.atv.15.9.1294] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A Finnish kindred with premature coronary heart disease and decreased HDL cholesterol levels was identified as having an apoA-I variant, apoA-I (Lys107-->0), caused by a 3-bp deletion of nucleotides 1396 through 1398 in exon 4 of the apoA-I gene. These subjects (n = 10) were heterozygous for this mutation. The mean serum HDL cholesterol concentration (26.7 +/- 9.7 mg/dL) of affected family members was 36%, lower than that of unaffected family members (P < .05). Mean serum apoA-I and apoA-II concentrations in heterozygotes were reduced by 18% and 22%, respectively, compared with normal family members (P < .05). In heterozygotes the mean concentration of lipoprotein containing both apoA-I and apoA-II (LpA-I:A-II) was 31% lower than in those with normal apoA-I (P < .001), while the mean level of lipoproteins containing apoA-I without apoA-II was similar in the two groups. HDL density-gradient ultracentrifugation showed a lack of HDL2 and small dense HDL3 in heterozygotes compared with unaffected family members. The HDL particle size distribution, as analyzed by nondenaturing gradient gel electrophoresis of heterozygotes, revealed one major peak at 8.0 to 9.7 nm, a minor peak at 7.8 to 8.5 nm, and an absence of HDL2b and HDL2a peaks. These latter peaks were observed in unaffected family members. Serum levels of LDL cholesterol, triglycerides, VLDL, IDL, and LDL subclasses were similar in the two groups. However, in heterozygotes the cholesterol-to-triglyceride ratios in VLDL2, LDL1, LDL3, HDL2b, HDL2a, and HDL3a were 8% to 54% lower than in unaffected family members (P < .05). Cholesteryl ester transfer protein activity in heterozygotes was reduced by 25% compared with unaffected family members (P < .05), while the plasma lecithin:cholesterol acyltransferase (LCAT) activity did not differ between heterozygotes and unaffected family members. The ability of isolated variant apoA-I to serve as a cofactor for LCAT in vitro did not differ from that of normal apoA-I. Our data are consistent with the concept that a low HDL cholesterol level in subjects heterozygous for the apoA-IHelsinki mutation (Lys107-->0) having normal LCAT activity is a consequence of decreased concentration of LpA-I:A-II particles and of a smaller size and reduced cholesterol content of HDL particles.
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Affiliation(s)
- M Tilly-Kiesi
- Third Department of Medicine, University of Helsinki, Finland
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7
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von Eckardstein A, Huang Y, Wu S, Funke H, Noseda G, Assmann G. Reverse cholesterol transport in plasma of patients with different forms of familial HDL deficiency. Arterioscler Thromb Vasc Biol 1995; 15:691-703. [PMID: 7749883 DOI: 10.1161/01.atv.15.5.691] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
HDLs encompass structurally heterogenous lipoproteins that fulfill specific functions in reverse cholesterol transport. Two-dimensional nondenaturing gradient gel electrophoresis (2D-PAGGE) of normoalphalipoproteinemic plasma and subsequent immunoblotting with anti-apoA-I-antibodies differentiates pre-beta 1-LpA-I, pre-beta 2-LpA-I, pre-beta 3-LpA-I, alpha-LpA-I2, and alpha-LpA-I3. Immunodetection with anti-apoE antibodies differentiates gamma-LpE and alpha-LpE. Pulse-chase incubations of plasma with [3H]unesterified cholesterol ([3H]UC)-labeled fibroblasts and subsequent 2D-PAGGE revealed that cell-derived [3H]UC is taken up by pre-beta 1-LpA-I and gamma-LpE. From these initial acceptors, [3H]UC is transferred to LDL via pre-beta 2-LpA-I-->pre-beta 3-LpA-I-->alpha-LpA-I. Some UC is esterified in pre-beta 3-LpA-I, and some is esterified in alpha-LpA-I after its retransfer from LDL. In this study we investigated the effect of various forms of familial HDL deficiency on reverse cholesterol transport. Plasma samples of patients with various forms of HDL deficiency are characterized by the lack of specific HDL subclasses. ApoE-containing HDLs, including gamma-LpE, are present in all kinds of HDL deficiency. However, all forms of LpA-I are absent in apoA-I-deficient plasma, pre-beta 3-LpA-I and alpha-LpA-I from the plasma of patients with Tangier disease (TD), and pre-beta 3-LpA-I and large alpha-LpA-I from the plasma of patients with lecithin:cholesterol acyltransferase (LCAT) deficiency and fish-eye disease (FED). After a 1-minute pulse with labeled fibroblasts, efflux of [3H]UC into HDL-deficient plasmas decreased, compared with normal plasma, by 49% (apoA-I deficiency), 36% (TD), 21% (LCAT deficiency), and 28% (FED). In apoA-I deficiency, only gamma-LpE takes up cell-derived [3H]UC. In the three other HDL-deficiency states, cell-derived [3H]UC is initially taken up by both pre-beta 1-LpA-I and gamma-LpE. The four HDL deficiencies are also characterized by differences in the esterification of cell-derived [3H]UC. No esterification occurs in LCAT-deficient plasma. In FED plasma, [3H]UC is esterified in LDL. In apoA-I deficiency and TD, however, [3H]UC is esterified in lipoproteins free of apoA-I and apoB. In the two latter cases, the transfer of [3H]cholesteryl ester to LDL is enhanced compared with normal plasma. The lack of specific HDL subclasses and the consequent changes in reverse cholesterol transport pathways differently affect net mass efflux of cholesterol from fibroblasts into HDL-deficient plasma.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- A von Eckardstein
- Institut für Klinische Chemie und Laboratoriumsmedizin, Zentrallaboratorium, Westfälische Wilhelms-Universität, Münster, FRG
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Duverger N, Ghalim N, Theret N, Fruchart JC, Castro G. Lipoproteins containing apolipoprotein A-IV: composition and relation to cholesterol esterification. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1211:23-8. [PMID: 8123678 DOI: 10.1016/0005-2760(94)90134-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In order to investigate the relationship of lipid and apolipoprotein composition to cholesterol esterification in lipoproteins containing apolipoprotein (apo) A-IV, apo A-containing lipoprotein particles were isolated from fresh human plasma using a system of sequential immunoaffinity chromatography. Plasma was first depleted of apo B- and apo E-containing lipoproteins. Four major subpopulations of apo A-containing lipoprotein particles were separated: Lp A-I, Lp A-I: A-II, Lp A-IV and Lp A-I: A-IV: A-II. Lp A-IV and Lp A-I: A-IV: A-II contained less total lipid, less cholesterol and more triacylglycerol than Lp A-I and Lp A-I: A-II. Lp A-IV and Lp A-I: A-IV: A-II contained more sphingomyelin and less phosphatidylcholine than Lp A-I and Lp A-I: A-II and were richer in (16:0 + 18:0) saturated fatty acids. Among these isolated lipoprotein particles, Lp A-IV contained the highest lecithin: cholesterol acyltransferase (LCAT) activity per micrograms of protein. Cholesterol esterification rates were 2.6 +/- 0.5, 5.3 +/- 0.4 and 0.8 +/- 0.2 mumol of cholesterol per hour per mg of lipoproteins for Lp A-IV, Lp A-I and Lp A-I: A-II, respectively. The apolipoprotein and lipid composition and LCAT activity of Lp A-IV suggest that this lipoprotein may be a source of cholesterol esterification in plasma.
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Affiliation(s)
- N Duverger
- Institut Pasteur, INSERM U325, Lille, France
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9
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Cheung MC. Distribution of lecithin-cholesterol acyltransferase in normolipidemic and dyslipidemic plasma. INTERNATIONAL JOURNAL OF CLINICAL & LABORATORY RESEARCH 1993; 23:30-3. [PMID: 8477088 DOI: 10.1007/bf02592277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Plasma lecithin-cholesterol acyltransferase levels and cholesterol esterification rates have been reported to be different between normolipidemic and dyslipidemic subjects. Since apolipoprotein A-I is the presumed primary physiological activator of lecithin-cholesterol acyltransferase, the distribution of the enzyme among A-I-containing lipoprotein particles and A-I-free plasma in normolipidemic and dyslipidemic subjects was examined. A-I-containing lipoprotein particles with and without apolipoprotein A-II were isolated from plasma by immunoaffinity chromatography, and the lecithin-cholesterol acyltransferase mass in these particles and in the A-I-free plasma was quantified by radioimmunoassay. The plasma lecithin-cholesterol acyltransferase concentration was comparable between normolipidemic men (5.9 +/- 1.1 micrograms/ml, n = 15) and women (5.8 +/- 1.1 micrograms/ml, n = 19), with 71 +/- 8% located in particles without apolipoprotein A-II, 17.6 +/- 6% in particles containing A-II, and 12 +/- 6% in the A-I-free plasma. In patients with elevated cholesterol (n = 12), triglyceride (n = 10), and with renal failure (n = 15) plasma levels of the enzyme were significantly higher (6.7 +/- 1.2, 6.9 +/- 1.3, and 6.6 +/- 1.3 micrograms/ml, respectively) (P < 0.05). In all three patient groups, a higher proportion of the enzyme (27 +/- 12%, 33 +/- 12%, and 19 +/- 9%) was not apo A-I associated. This phenomenon was also observed in plasma samples after incubation at 37 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M C Cheung
- Department of Medicine, School of Medicine, University of Washington, Seattle 98103
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Cheung MC, Mendez AJ, Wolf AC, Knopp RH. Characterization of apolipoprotein A-I- and A-II-containing lipoproteins in a new case of high density lipoprotein deficiency resembling Tangier disease and their effects on intracellular cholesterol efflux. J Clin Invest 1993; 91:522-9. [PMID: 8432861 PMCID: PMC287973 DOI: 10.1172/jci116231] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A 48-yr-old Caucasian female of central European origin (subject IM) with low plasma cholesterol and normal plasma triglyceride (TG) had extremely low apo A-I (6 mg/dl), A-II (5 mg/dl), and HDL cholesterol (2 mg/dl) levels. She had most of the clinical symptoms typically associated with Tangier disease, including early corneal opacities, yellow-streaked tonsils, hepatomegaly, and variable degrees of peripheral neuropathy, but had no splenomegaly. She had a myocardial infarction at age 46. Since HDL are postulated to be involved in the transport of excess cholesterol from peripheral tissues to the liver for degradation, and the ability of an HDL particle to promote cellular cholesterol efflux appears to be related to its density, size, and apo A-I and A-II contents, we isolated and characterized the HDL particles of this patient and all her first degree relatives (mother, a brother, and two children). The plasma A-I, A-II, and HDL cholesterol levels of all five relatives were either normal or high. Using anti-A-I and anti-A-II immunosorbents, we found three populations of particles in IM: one contained both apo A-I and A-II, Lp(AI w AII); one contained apo A-I but no A-II, Lp(AI w/o AII); and the third (an unusual one) contained apo A-II but no A-I, Lp(AII). Two-thirds of her plasma A-I and A-II existed in separate HDL particles, i.e., in Lp(AI w/o AII) and Lp(AII), respectively. Only Lp(AI w AII) and Lp(AI w/o AII) were present in the plasma of the relatives. All three populations of the patient's HDL particles had a normal core/surface lipid ratio, but the cores were enriched with TG. The apo A-I-containing particles, however, were considerably smaller and contained much less lipid than Lp(AII). Despite these unusual physicochemical characteristics, the apo A-I-containing particles and Lp(AII) were effective suppressors of intracellular cholesterol esterification in cholesterol-loaded human skin fibroblast. The patient's plasma apo D and lecithin cholesterol acyltransferase levels were reduced, with an increased proportion located in non-HDL plasma fractions. These findings are discussed in light of Tangier disease and other known HDL-deficiency cases, and the role of HDL in the maintenance of cell cholesterol homeostasis.
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Affiliation(s)
- M C Cheung
- Department of Medicine, School of Medicine, University of Washington, Seattle
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Subbaiah PV, Norum RA, Bagdade JD. Effect of apolipoprotein activators on the specificity of lecithin:cholesterol acyltransferase: determination of cholesteryl esters formed in A-I/C-III deficiency. J Lipid Res 1991. [DOI: 10.1016/s0022-2275(20)41645-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Jonas A. Lecithin-cholesterol acyltransferase in the metabolism of high-density lipoproteins. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1084:205-20. [PMID: 1888769 DOI: 10.1016/0005-2760(91)90062-m] [Citation(s) in RCA: 170] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- A Jonas
- Department of Biochemistry, College of Medicine, University of Illinois at Urbana-Champaign 61801
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13
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Cheung MC, Wolf AC. In vitro transformation of apoA-I-containing lipoprotein subpopulations: role of lecithin:cholesterol acyltransferase and apoB-containing lipoproteins. J Lipid Res 1989. [DOI: 10.1016/s0022-2275(20)38338-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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14
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Inhibition of lipid transfer by a unique high density lipoprotein subclass containing an inhibitor protein. J Lipid Res 1989. [DOI: 10.1016/s0022-2275(20)38377-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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