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Othman A, Liu M, Bode H, Boudyguina E, von Eckardstein A, Parks JS, Hornemann T. Hepatocyte ABCA1 deficiency is associated with reduced HDL sphingolipids. Front Physiol 2023; 14:1208719. [PMID: 37601634 PMCID: PMC10436503 DOI: 10.3389/fphys.2023.1208719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/13/2023] [Indexed: 08/22/2023] Open
Abstract
ATP binding cassette transporter A1 (ABCA1) limits the formation of high density lipoproteins (HDL) as genetic loss of ABCA1 function causes virtual HDL deficiency in patients with Tangier disease. Mice with a hepatocyte-specific ABCA1 knockout (Abca1 HSKO) have 20% of wild type (WT) plasma HDL-cholesterol levels, suggesting a major contribution of hepatic ABCA1 to the HDL phenotype. Whether plasma sphingolipids are reduced in Tangier disease and to what extent hepatic ABCA1 contributes to plasma sphingolipid (SL) levels is unknown. Here, we report a drastic reduction of total SL levels in plasma of a Tangier patient with compound heterozygosity for mutations in ABCA1. Compared to mutation-free controls, heterozygous mutations in ABCA1 had no significant effect on total SLs in plasma; however, apoB-depleted plasma showed a reduction in total SL also in het carriers. Similarly, liver specific Abca1 KO mice (Abca1 HSKO) showed reduced total sphingolipids in plasma and liver. In parallel, apoM and sphingosine-1-phosphate (S1P) levels were reduced in plasma of Abca1 HSKO mice. Primary hepatocytes from Abca1 HSKO mice showed a modest, but significant reduction in total SLs concentration compared to WT hepatocytes, although SL de novo synthesis and secretion were slightly increased in Abca1 HSKO hepatocytes. We conclude that hepatic ABCA1 is a signficant contributor to maintaining total plasma pool of HDL sphingolipids, including sphingomyelins and S1P.
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Affiliation(s)
- Alaa Othman
- Institute of Clinical Chemistry, University Hospital Zurich and University Zurich, Zurich, Switzerland
| | - Mingxia Liu
- Department of Internal Medicine-Section on Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Heiko Bode
- Institute of Clinical Chemistry, University Hospital Zurich and University Zurich, Zurich, Switzerland
| | - Elena Boudyguina
- Department of Internal Medicine-Section on Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Arnold von Eckardstein
- Institute of Clinical Chemistry, University Hospital Zurich and University Zurich, Zurich, Switzerland
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - John S. Parks
- Department of Internal Medicine-Section on Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Thorsten Hornemann
- Institute of Clinical Chemistry, University Hospital Zurich and University Zurich, Zurich, Switzerland
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2
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Ohkawa R, Low H, Mukhamedova N, Fu Y, Lai SJ, Sasaoka M, Hara A, Yamazaki A, Kameda T, Horiuchi Y, Meikle PJ, Pernes G, Lancaster G, Ditiatkovski M, Nestel P, Vaisman B, Sviridov D, Murphy A, Remaley AT, Sviridov D, Tozuka M. Cholesterol transport between red blood cells and lipoproteins contributes to cholesterol metabolism in blood. J Lipid Res 2020; 61:1577-1588. [PMID: 32907987 DOI: 10.1194/jlr.ra120000635] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Lipoproteins play a key role in transport of cholesterol to and from tissues. Recent studies have also demonstrated that red blood cells (RBCs), which carry large quantities of free cholesterol in their membrane, play an important role in reverse cholesterol transport. However, the exact role of RBCs in systemic cholesterol metabolism is poorly understood. RBCs were incubated with autologous plasma or isolated lipoproteins resulting in a significant net amount of cholesterol moved from RBCs to HDL, while cholesterol from LDL moved in the opposite direction. Furthermore, the bi-directional cholesterol transport between RBCs and plasma lipoproteins was saturable and temperature-, energy-, and time-dependent, consistent with an active process. We did not find LDLR, ABCG1, or scavenger receptor class B type 1 in RBCs but found a substantial amount of ABCA1 mRNA and protein. However, specific cholesterol efflux from RBCs to isolated apoA-I was negligible, and ABCA1 silencing with siRNA or inhibition with vanadate and Probucol did not inhibit the efflux to apoA-I, HDL, or plasma. Cholesterol efflux from and cholesterol uptake by RBCs from Abca1 +/+ and Abca1 -/- mice were similar, arguing against the role of ABCA1 in cholesterol flux between RBCs and lipoproteins. Bioinformatics analysis identified ABCA7, ABCG5, lipoprotein lipase, and mitochondrial translocator protein as possible candidates that may mediate the cholesterol flux. Together, these results suggest that RBCs actively participate in cholesterol transport in the blood, but the role of cholesterol transporters in RBCs remains uncertain.
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Affiliation(s)
- Ryunosuke Ohkawa
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Baker Heart and Diabetes Institute, Melbourne, Australia.
| | - Hann Low
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | | | - Ying Fu
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Shao-Jui Lai
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Mai Sasaoka
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ayuko Hara
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Azusa Yamazaki
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takahiro Kameda
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yuna Horiuchi
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Peter J Meikle
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Gerard Pernes
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | | | | | - Paul Nestel
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Boris Vaisman
- Lipoprotein Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Denis Sviridov
- Lipoprotein Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Andrew Murphy
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Alan T Remaley
- Lipoprotein Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Dmitri Sviridov
- Baker Heart and Diabetes Institute, Melbourne, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia.
| | - Minoru Tozuka
- Department of Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Life Science Research Center, Nagano Children's Hospital, Azumino, Japan
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3
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Abstract
Cholesterol homeostasis is of central importance for life. Therefore, cells have developed a divergent set of pathways to meet their cholesterol needs. In this review, we focus on the direct transfer of cholesterol from lipoprotein particles to the cell membrane. More molecular details on the transfer of lipoprotein-derived lipids were gained by recent studies using phospholipid bilayers. While amphiphilic lipids are transferred right after contact of the lipoprotein particle with the membrane, the transfer of core lipids is restricted. Amphiphilic lipid transfer gains special importance in genetic diseases impairing lipoprotein metabolism like familial hypercholesterolemia. Taken together, these data indicate that there is a constant exchange of amphiphilic lipids between lipoprotein particles and the cell membrane.
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4
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Tarasev M, Chakraborty S, Light L, Davenport R. Impact of environment on Red Blood Cell ability to withstand mechanical stress. Clin Hemorheol Microcirc 2016; 64:21-33. [DOI: 10.3233/ch-152037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- M. Tarasev
- Blaze Medical Devices, Ann Arbor, MI, USA
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5
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van Zwieten R, Bochem AE, Hilarius PM, van Bruggen R, Bergkamp F, Hovingh GK, Verhoeven AJ. The cholesterol content of the erythrocyte membrane is an important determinant of phosphatidylserine exposure. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1493-500. [PMID: 22960544 DOI: 10.1016/j.bbalip.2012.08.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 08/07/2012] [Accepted: 08/09/2012] [Indexed: 10/27/2022]
Abstract
Maintenance of the asymmetric distribution of phospholipids across the plasma membrane is a prerequisite for the survival of erythrocytes. Various stimuli have been shown to induce scrambling of phospholipids and thereby exposure of phosphatidylserine (PS). In two types of patients, both with aberrant plasma cholesterol levels, we observed an aberrant PS exposure in erythrocytes upon stimulation. We investigated the effect of high and low levels of cholesterol on the ATP-dependent flippase, which maintains phospholipid asymmetry, and the ATP-independent scrambling activity, which breaks down phospholipid asymmetry. We analyzed erythrocytes of a patient with spur cell anemia, characterized by elevated plasma cholesterol, and the erythrocytes of Tangier disease patients with very low levels of plasma cholesterol. In normal erythrocytes, loaded with cholesterol or depleted of cholesterol in vitro, the same analyses were performed. Changes in the cholesterol/phospholipid ratio of erythrocytes had marked effects on PS exposure upon cell activation. Excess cholesterol profoundly inhibited PS exposure, whereas cholesterol depletion led to increased PS exposure. The activity of the ATP-dependent flippase was not changed, suggesting a major influence of cholesterol on the outward translocation of PS. The effects of cholesterol were not accompanied by eminent changes in cytoskeletal and membrane proteins. These findings emphasize the importance of cholesterol exchange between circulating plasma and the erythrocyte membrane as determinant for phosphatidylserine exposure in erythrocytes.
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Affiliation(s)
- Rob van Zwieten
- Laboratory of Red Blood Cell Diagnostics, Dept. of Blood Cell Research, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.
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6
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Dole VS, Matuskova J, Vasile E, Yesilaltay A, Bergmeier W, Bernimoulin M, Wagner DD, Krieger M. Thrombocytopenia and platelet abnormalities in high-density lipoprotein receptor-deficient mice. Arterioscler Thromb Vasc Biol 2008; 28:1111-6. [PMID: 18436807 DOI: 10.1161/atvbaha.108.162347] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE High-density lipoprotein (HDL) receptor, scavenger receptor class B, type I (SR-BI), mediated cellular uptake of lipoprotein cholesterol controls HDL structure and plasma HDL and biliary cholesterol levels. In SR-BI knockout (KO) mice, an unusually high plasma unesterified-to-total cholesterol ratio (UC:TC) and abnormally large HDL particles apparently contribute to pathology, including female infertility, susceptibility to atherosclerosis and coronary heart disease, and anemia. Here we examined the influence of SR-BI deficiency on platelets. METHODS AND RESULTS The high plasma UC:TC ratio in SR-BI KO mice was correlated with platelet abnormalities, including high cholesterol content, abnormal morphologies, high clearance rates, and thrombocytopenia. One day after platelets from wild-type mice were infused into SR-BI KO mice, they exhibited abnormally high cholesterol content and clearance rates similar to those of endogenous platelets. Platelets from SR-BI KO mice exhibited in vitro a blunted aggregation response to the agonist ADP but a normal response to PAR4. CONCLUSIONS In SR-BI KO mice abnormal circulating lipoproteins, particularly their high UC:TC ratio-rather than the absence of SR-BI in platelets themselves-induce defects in platelet structure and clearance, together with a mild defect in function.
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Affiliation(s)
- Vandana S Dole
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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7
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Feoli-Fonseca JC, Lévy E, Godard M, Lambert M. Familial lipoprotein lipase deficiency in infancy: clinical, biochemical, and molecular study. J Pediatr 1998; 133:417-23. [PMID: 9738727 DOI: 10.1016/s0022-3476(98)70280-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES To describe the characteristics of lipoprotein lipase (LPL)-deficient patients seen in infancy and to evaluate the safety and efficacy of severe fat restriction. METHODS Children <1 year old presenting with chylomicronemia between 1972 and 1995 were identified, and their clinical courses were reviewed retrospectively. RESULTS LPL deficiency was demonstrated in 16 infants who presented with irritability (n = 7), lower intestinal bleeding (n = 2), pallor, anemia, or splenomegaly (n = 5), and a family history or fortuitous discovery (n = 2). All plasma samples were lactescent at presentation. Chylomicronemia responded rapidly to dietary fat restriction, and it was possible to maintain satisfactory metabolic control for a prolonged period of time. Only 1 adolescent girl had an episode of pancreatitis associated with the use of oral contraceptives. No persistent adverse effects on growth were seen. We obtained abnormal values for serum iron, alkaline phosphatase, and total calcium. CONCLUSIONS The presentation of LPL deficiency is heterogeneous during infancy. Close dietary monitoring is required to avoid nutritional deficiencies. Estrogen therapy should be avoided in LPL-deficient patients.
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Affiliation(s)
- J C Feoli-Fonseca
- Department of Pediatrics, St-Justine Hospital, University of Montreal, Quebec, Canada
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8
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Cantin B, Boudriau S, Bertrand M, Brun LD, Gagné C, Rogers PA, Ven Murthy MR, Lupien PJ, Julien P. Hemolysis in primary lipoprotein lipase deficiency. Metabolism 1995; 44:652-8. [PMID: 7752915 DOI: 10.1016/0026-0495(95)90124-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A slight to moderate hemolysis is often present in plasma from patients with primary lipoprotein lipase (LPL) deficiency. To determine the nature of this hemolysis, we measured erythrocyte hypo-osmotic fragility, plasma free hemoglobin, and phospholipid composition in 26 patients with primary LPL deficiency and 21 unrelated controls. In some patients, these investigations were completed by erythrocyte cytoskeletal protein determinations and abdominal echography. Osmotic fragility was similar between control subjects and patients. However, there was a significantly increased concentration of plasma free hemoglobin in primary LPL deficiency (0.282 +/- 0.331 v 0.048 +/- 0.038 g/L in controls, P < .005). In LPL-deficient patients, an increase of plasma lysophosphatidylcholine concentration (12.6% +/- 5.8% v 6.4% +/- 1.9% in controls, P < .0001) was also found. The protein composition of the erythrocyte membrane skeleton was abnormal in some LPL-deficient patients and splenomegaly was present in 12, but these abnormalities did not correlate with plasma free hemoglobin levels. Bilirubin and haptoglobin levels were also within physiologic ranges in these patients, suggesting that the observed hemolysis did not result from hypersplenism. It appears likely that the accumulation of lysophosphatidylcholine was due to an impairment in the reverse metabolic pathway converting lysophosphatidylcholine back to phosphatidylcholine. Collectively, these data, along with a positive correlation between plasma free hemoglobin and lysophosphatidylcholine levels (r = .58, P = .0001), suggest that the hemolysis observed in primary LPL deficiency is mediated to some extent by the abnormally elevated concentration of lysophosphatidylcholine.
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Affiliation(s)
- B Cantin
- Centre de Recherche sur les Maladies Lipidiques, Le Centre Hospitalier de l'Université Laval, Ste-Foy, Québec, Canada
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9
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Cantin B, Brun LD, Gagné C, Murthy MR, Lupien PJ, Julien P. Alterations in erythrocyte membrane lipid composition and fluidity in primary lipoprotein lipase deficiency. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1139:25-31. [PMID: 1610917 DOI: 10.1016/0925-4439(92)90078-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Lipid composition of plasma lipoproteins and erythrocyte ghost membranes has been studied in 16 healthy normolipidaemic subjects and in 16 patients affected by primary lipoprotein lipase deficiency, resulting in severe chylomicronaemia and in cholesterol-depleted low-density lipoproteins and high-density lipoproteins. A significant decrease in membrane cholesterol/phospholipid ratio was observed in lipoprotein lipase deficient patients compared to controls (3.27 +/- 0.33 vs. 3.95 +/- 0.50, mean +/- S.D.; P less than 0.0001). There was also an increase in the erythrocyte membrane phosphatidylcholine/sphingomyelin ratio in lipoprotein lipase deficient patients compared to controls (1.53 +/- 0.10 vs. 1.05 +/- 0.13; P less than 0.0001) due to a concurrent increase in phosphatidylcholine and decrease in sphingomyelin relative concentrations in these patients. Erythrocyte ghost membrane fluidity was determined by fluorescence anisotropy and found to be higher in membranes from lipoprotein lipase deficient patients. This increase in membrane fluidity can be attributed in part to changes in membrane cholesterol and phospholipid concentrations in response to abnormal plasma lipoprotein composition.
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Affiliation(s)
- B Cantin
- Lipid Research Centre, CHUL Research Centre, Québec, Canada
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10
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Reinhart WH, Gössi U, Bütikofer P, Ott P, Sigrist H, Schatzmann HJ, Lutz HU, Straub PW. Haemolytic anaemia in analpha-lipoproteinaemia (Tangier disease): morphological, biochemical, and biophysical properties of the red blood cell. Br J Haematol 1989; 72:272-7. [PMID: 2757970 DOI: 10.1111/j.1365-2141.1989.tb07694.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A patient with familial analpha-lipoproteinaemia (Tangier disease) was found to have stomatocytosis and haemolytic anaemia. The analysis of the red cell membrane constituents revealed a low cholesterol content (90 nmol/ml red cells, control 130 nmol/ml red cells), a decreased cholesterol/phospholipid ratio (0.54, control 0.78), high phosphatidylcholine (41.5%, control 30.6%) and low sphingomyelin (18.8%, control 27.6%). The electrophoretic membrane protein pattern was normal. Osmotic gradient ektacytometry and osmotic resistance showed a decreased surface/volume ratio, which caused an increased filtration resistance in 3 microns pores. The elasticity of the membrane was unchanged. Functional membrane properties were altered: the anion exchange rate was increased, whereas alkali cation fluxes were normal. The capacity to release vesicles was reduced. This case represented a new type of stomatocytosis. It contributes to the understanding of the role of cholesterol and phospholipids in the red cell membrane and biomembranes in general.
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Affiliation(s)
- W H Reinhart
- Department of Internal Medicine, Inselspital, Zürich, Switzerland
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11
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Gheeraert P, De Buyzere M, Delanghe J, De Scheerder I, Bury J, Rosseneu M. Plasma and erythrocyte lipids in two families with heterozygous hypobetalipoproteinemia. Clin Biochem 1988; 21:371-7. [PMID: 3233750 DOI: 10.1016/s0009-9120(88)80020-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Erythrocyte morphology, kinematic viscosity, and membrane lipid composition have not been well documented in heterozygous hypobetalipoproteinemia (HBL). In our study of nine subjects with HBL from two kindreds, three presented with schistocytes (3-6%) while two of them also showed acanthocytosis (25-35%) on their peripheral blood films. The other affected family members had a normal RBC morphology despite a decreased kinematic viscosity of RBC suspension at 37 degrees C (log eta = 0.20 +/- 0.02 vs. log eta = 0.26 +/- 0.02) in all nine subjects; erythrocyte osmotic fragility however was normal. Although some subjects showed acanthocytosis total cholesterol (0.63 +/- 0.05 mol x 10(-6)/mg membrane protein) and sphingomyelin/lecithin ratio (0.905 +/- 0.042) of RBC membranes were normal while plasma from the subject with schistocytosis had a significantly decreased sphingomyelin/lecithin ratio in plasma (17.2 +/- 2.4 vs. 29.1 +/- 3.3) suggesting that sphingomyelin and lecithin are not freely exchangeable between plasma and the outer surface of RBC membranes.
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Affiliation(s)
- P Gheeraert
- Department of Clinical Chemistry, University Hospital Ghent, Belgium
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12
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Godin DV, Garnett ME, Hoag G, Wadsworth LD, Frohlich J. Erythrocyte abnormalities in a hypoalphalipoproteinemia syndrome resembling fish eye disease. Eur J Haematol Suppl 1988; 41:176-81. [PMID: 3410011 DOI: 10.1111/j.1600-0609.1988.tb00888.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Erythrocyte membrane (EM) abnormalities in a 16-yr-old boy with hypoalphalipoproteinemia resembling fish eye disease (FED-LS) were investigated. The proband's erythrocytes had markedly decreased osmotic fragility with target cells observed in the peripheral film. Analysis of his EM lipids revealed normal cholesterol and phospholipid content but a marked increase in phosphatidylcholine with concomitant decreases in phosphatidylethanolamine and sphingomyelin. Of the EM enzymes examined, acetylcholinesterase and superoxide dismutase activities were decreased while those of Na+-K+ ATPase, catalase and glutathione reductase were normal. 51Cr erythrocyte survival in the patient was slightly decreased. The observed changes in a number of structural and functional properties of erythrocytes in this disorder are indistinguishable from those previously described in homozygotes for familial lecithin:cholesterol acyltransferase (LCAT) deficiency. Thus, it is possible that in both of these disorders an abnormality of plasma LCAT activity causes, either directly or indirectly, functional and structural changes in the erythrocyte membrane.
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Affiliation(s)
- D V Godin
- Department of Pharmacology, University of British Columbia, Vancouver, Canada
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