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Vyletelová V, Nováková M, Pašková Ľ. Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies. Pharmaceuticals (Basel) 2022; 15:1278. [PMID: 36297390 PMCID: PMC9611871 DOI: 10.3390/ph15101278] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/03/2022] [Accepted: 10/14/2022] [Indexed: 09/10/2023] Open
Abstract
Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.
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Affiliation(s)
| | | | - Ľudmila Pašková
- Department of Cell and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University, 83232 Bratislava, Slovakia
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2
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Jiang XC, Yu Y. The Role of Phospholipid Transfer Protein in the Development of Atherosclerosis. Curr Atheroscler Rep 2021; 23:9. [PMID: 33496859 DOI: 10.1007/s11883-021-00907-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2021] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW Phospholipid transfer protein (PLTP), a member of lipid transfer protein family, is an important protein involved in lipid metabolism in the circulation. This article reviews recent PLTP research progresses, involving lipoprotein metabolism and atherogenesis. RECENT FINDINGS PLTP activity influences atherogenic and anti-atherogenic lipoprotein levels. Human serum PLTP activity is a risk factor for human cardiovascular disease and is an independent predictor of all-cause mortality. PLTP deficiency reduces VLDL and LDL levels and attenuates atherosclerosis in mouse models, while PLTP overexpression exerts an opposite effect. Both PLTP deficiency and overexpression result in reduction of HDL which has different size, inflammatory index, and lipid composition. Moreover, although both PLTP deficiency and overexpression reduce cholesterol efflux capacity, but this effect has no impact in macrophage reverse cholesterol transport in mice. Furthermore, PLTP activity is related with metabolic syndrome, thrombosis, and inflammation. PLTP could be target for the treatment of dyslipidemia and atherosclerosis, although some potential off-target effects should be noted.
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Affiliation(s)
- Xian-Cheng Jiang
- Department of Cell Biology, SUNY Downstate Health Sciences University, 450 Clarkson Ave, Brooklyn, NY, USA.
| | - Yang Yu
- Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271000, People's Republic of China
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3
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Impact of Phospholipid Transfer Protein in Lipid Metabolism and Cardiovascular Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1276:1-13. [PMID: 32705590 DOI: 10.1007/978-981-15-6082-8_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PLTP plays an important role in lipoprotein metabolism and cardiovascular disease development in humans; however, the mechanisms are still not completely understood. In mouse models, PLTP deficiency reduces cardiovascular disease, while its overexpression induces it. Therefore, we used mouse models to investigate the involved mechanisms. In this chapter, the recent main progresses in the field of PLTP research are summarized, and our focus is on the relationship between PLTP and lipoprotein metabolism, as well as PLTP and cardiovascular diseases.
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4
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Jiang XC. Phospholipid transfer protein: its impact on lipoprotein homeostasis and atherosclerosis. J Lipid Res 2018; 59:764-771. [PMID: 29438986 DOI: 10.1194/jlr.r082503] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/10/2018] [Indexed: 12/25/2022] Open
Abstract
Phospholipid transfer protein (PLTP) is one of the major modulators of lipoprotein metabolism and atherosclerosis development in humans; however, we still do not quite understand the mechanisms. In mouse models, PLTP overexpression induces atherosclerosis, while its deficiency reduces it. Thus, mouse models were used to explore the mechanisms. In this review, I summarize the major progress made in the PLTP research field and emphasize its impact on lipoprotein metabolism and atherosclerosis, as well as its regulation.
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Affiliation(s)
- Xian-Cheng Jiang
- Department of Cell Biology, Downstate Medical Center, State University of New York, Brooklyn, NY
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5
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Elevated Phospholipid Transfer Protein in Subjects with Multiple Sclerosis. J Lipids 2015; 2015:518654. [PMID: 26347820 PMCID: PMC4549613 DOI: 10.1155/2015/518654] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 07/17/2015] [Accepted: 07/30/2015] [Indexed: 11/18/2022] Open
Abstract
An anomaly in the plasma proteins of patients with multiple sclerosis detectable on SDS-PAGE has been reported. The molecular weight of the anomaly was the same as the phospholipid transfer protein. A metabolic protein was involved in lipid homeostasis and remodeling of the high density lipoproteins. We have identified the anomaly as the phospholipid transfer protein by western blot using antiphospholipid transfer antibodies. Activity assays showed that the phospholipid transfer activity was elevated in fasted plasma samples from subjects with MS compared to controls. Sequence analysis of the gene encoding the phospholipid transfer protein did not identify any mutations in the genetic structure, suggesting that the increase in activity was not due to structural changes in the protein, but may be due to one of the other proteins with which it forms active complexes. Altered phospholipid transfer activity is important because it could be implicated in the decreased lipid uptake and abnormal myelin lipids observed in multiple sclerosis. It has been shown that alteration in myelin lipid content is an epitope for autoimmunity. Therefore, lipid changes due to a defect in phospholipid transfer and/or uptake could potentially influence the course of the disease. Further research is needed to elucidate the role of the phospholipid transfer protein in subjects with multiple sclerosis.
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Kim DS, Burt AA, Ranchalis JE, Vuletic S, Vaisar T, Li WF, Rosenthal EA, Dong W, Eintracht JF, Motulsky AG, Brunzell JD, Albers JJ, Furlong CE, Jarvik GP. PLTP activity inversely correlates with CAAD: effects of PON1 enzyme activity and genetic variants on PLTP activity. J Lipid Res 2015; 56:1351-62. [PMID: 26009633 DOI: 10.1194/jlr.p058032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Indexed: 01/07/2023] Open
Abstract
Recent studies have failed to demonstrate a causal cardioprotective effect of HDL cholesterol levels, shifting focus to the functional aspects of HDL. Phospholipid transfer protein (PLTP) is an HDL-associated protein involved in reverse cholesterol transport. This study sought to determine the genetic and nongenetic predictors of plasma PLTP activity (PLTPa), and separately, to determine whether PLTPa predicted carotid artery disease (CAAD). PLTPa was measured in 1,115 European ancestry participants from a case-control study of CAAD. A multivariate logistic regression model was used to elucidate the relationship between PLTPa and CAAD. Separately, a stepwise linear regression determined the nongenetic clinical and laboratory characteristics that best predicted PLTPa. A final stepwise regression considering both nongenetic and genetic variables identified the combination of covariates that explained maximal PLTPa variance. PLTPa was significantly associated with CAAD (7.90 × 10(-9)), with a 9% decrease in odds of CAAD per 1 unit increase in PLTPa (odds ratio = 0.91). Triglyceride levels (P = 0.0042), diabetes (P = 7.28 × 10(-5)), paraoxonase 1 (PON1) activity (P = 0.019), statin use (P = 0.026), PLTP SNP rs4810479 (P = 6.38 × 10(-7)), and PCIF1 SNP rs181914932 (P = 0.041) were all significantly associated with PLTPa. PLTPa is significantly inversely correlated with CAAD. Furthermore, we report a novel association between PLTPa and PON1 activity, a known predictor of CAAD.
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Affiliation(s)
- Daniel Seung Kim
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA Department of Biostatistics, University of Washington School of Public Health, Seattle, WA
| | - Amber A Burt
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Jane E Ranchalis
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Simona Vuletic
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Seattle, WA Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Tomas Vaisar
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Wan-Fen Li
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Elisabeth A Rosenthal
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Weijiang Dong
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Seattle, WA Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA Department of Human Anatomy and Histology and Embryology, Xi'an Jiaotong University School of Medicine, Xi'an 710061, People's Republic of China
| | - Jason F Eintracht
- Department of General Medicine, Virginia Mason Medical Center, Seattle, WA
| | - Arno G Motulsky
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA
| | - John D Brunzell
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - John J Albers
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Seattle, WA Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA
| | - Clement E Furlong
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA
| | - Gail P Jarvik
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA
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Miller NE, Olszewski WL, Hattori H, Miller IP, Kujiraoka T, Oka T, Iwasaki T, Nanjee MN. Lipoprotein remodeling generates lipid-poor apolipoprotein A-I particles in human interstitial fluid. Am J Physiol Endocrinol Metab 2013; 304:E321-8. [PMID: 23233540 PMCID: PMC3566430 DOI: 10.1152/ajpendo.00324.2012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although much is known about the remodeling of high density lipoproteins (HDLs) in blood, there is no information on that in interstitial fluid, where it might have a major impact on the transport of cholesterol from cells. We incubated plasma and afferent (prenodal) peripheral lymph from 10 healthy men at 37°C in vitro and followed the changes in HDL subclasses by nondenaturing two-dimensional crossed immunoelectrophoresis and size-exclusion chromatography. In plasma, there was always initially a net conversion of small pre-β-HDLs to cholesteryl ester (CE)-rich α-HDLs. By contrast, in lymph, there was only net production of pre-β-HDLs from α-HDLs. Endogenous cholesterol esterification rate, cholesteryl ester transfer protein (CETP) concentration, CE transfer activity, phospholipid transfer protein (PLTP) concentration, and phospholipid transfer activity in lymph averaged 5.0, 10.4, 8.2, 25.0, and 82.0% of those in plasma, respectively (all P < 0.02). Lymph PLTP concentration, but not phospholipid transfer activity, was positively correlated with that in plasma (r = +0.63, P = 0.05). Mean PLTP-specific activity was 3.5-fold greater in lymph, reflecting a greater proportion of the high-activity form of PLTP. These findings suggest that cholesterol esterification rate and PLTP specific activity are differentially regulated in the two matrices in accordance with the requirements of reverse cholesterol transport, generating lipid-poor pre-β-HDLs in the extracellular matrix for cholesterol uptake from neighboring cells and converting pre-β-HDLs to α-HDLs in plasma for the delivery of cell-derived CEs to the liver.
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8
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Jiang XC, Jin W, Hussain MM. The impact of phospholipid transfer protein (PLTP) on lipoprotein metabolism. Nutr Metab (Lond) 2012; 9:75. [PMID: 22897926 PMCID: PMC3495888 DOI: 10.1186/1743-7075-9-75] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 06/30/2012] [Indexed: 02/05/2023] Open
Abstract
It has been reported that phospholipid transfer protein (PLTP) is an independent risk factor for human coronary artery disease. In mouse models, it has been demonstrated that PLTP overexpression induces atherosclerosis, while its deficiency reduces it. PLTP is considered a promising target for pharmacological intervention to treat atherosclerosis. However, we must still answer a number of questions before its pharmaceutical potential can be fully explored. In this review, we summarized the recent progresses made in the PLTP research field and focused on its effect on apoB-containing- triglyceride-rich particle and HDL metabolism.
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Affiliation(s)
- Xian-Cheng Jiang
- Department of Cell Biology, Downstate Medical Center, State University of New York, 450 Clarkson Ave,, Box 5, Brooklyn, NY, 11203, USA.
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Rosenson RS, Brewer HB, Davidson WS, Fayad ZA, Fuster V, Goldstein J, Hellerstein M, Jiang XC, Phillips MC, Rader DJ, Remaley AT, Rothblat GH, Tall AR, Yvan-Charvet L. Cholesterol efflux and atheroprotection: advancing the concept of reverse cholesterol transport. Circulation 2012; 125:1905-19. [PMID: 22508840 PMCID: PMC4159082 DOI: 10.1161/circulationaha.111.066589] [Citation(s) in RCA: 695] [Impact Index Per Article: 57.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Robert S Rosenson
- Mount Sinai Heart, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1030, New York, NY 10029, USA.
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10
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Albers JJ, Vuletic S, Cheung MC. Role of plasma phospholipid transfer protein in lipid and lipoprotein metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:345-57. [PMID: 21736953 DOI: 10.1016/j.bbalip.2011.06.013] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 06/01/2011] [Accepted: 06/14/2011] [Indexed: 12/13/2022]
Abstract
The understanding of the physiological and pathophysiological role of PLTP has greatly increased since the discovery of PLTP more than a quarter of century ago. A comprehensive review of PLTP is presented on the following topics: PLTP gene organization and structure; PLTP transfer properties; different forms of PLTP; characteristics of plasma PLTP complexes; relationship of plasma PLTP activity, mass and specific activity with lipoprotein and metabolic factors; role of PLTP in lipoprotein metabolism; PLTP and reverse cholesterol transport; insights from studies of PLTP variants; insights of PLTP from animal studies; PLTP and atherosclerosis; PLTP and signal transduction; PLTP in the brain; and PLTP in human disease. PLTP's central role in lipoprotein metabolism and lipid transport in the vascular compartment has been firmly established. However, more studies are needed to further delineate PLTP's functions in specific tissues, such as the lung, brain and adipose tissue. Furthermore, the specific role that PLTP plays in human diseases, such as atherosclerosis, cancer, or neurodegenerative disease, remains to be clarified. Exciting directions for future research include evaluation of PLTP's physiological relevance in intracellular lipid metabolism and signal transduction, which undoubtedly will advance our knowledge of PLTP functions in health and disease. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).
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Affiliation(s)
- John J Albers
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA.
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Cheung MC, Wolfbauer G, Albers JJ. Different phospholipid transfer protein complexes contribute to the variation in plasma PLTP specific activity. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:343-7. [PMID: 21303701 DOI: 10.1016/j.bbalip.2011.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 01/15/2011] [Accepted: 02/01/2011] [Indexed: 11/28/2022]
Abstract
Phospholipid transfer protein (PLTP) facilitates the transfer of phospholipids among lipoproteins. Over half of the PLTP in human plasma has been found to have little phospholipid transfer activity (inactive PLTP). We recently observed that plasma PLTP specific activity is inversely correlated with high-density lipoprotein (HDL) level and particle size in healthy adults. The purpose of this study was to evaluate the factors that contribute to the variation in plasma PLTP specific activity. Analysis of the specific activity of PLTP complexes in nine plasma samples from healthy adults revealed two clusters of inactive PLTP complexes with mean molecular weights (MW) of 342kDa and 146kDa. The large and small inactive PLTP complexes represented 52±8% (range 39-63%) and 8±8% (range 1-28%) of the plasma PLTP, respectively. Active PLTP complexes had a mean MW of 207kDa and constituted 40±6% (range 33-50%) of the plasma PLTP. The specific activity of active PLTP varied from 16 to 32μmol/μg/h. These data demonstrate for the first time the existence of small inactive plasma PLTP complexes. Variation in the amount of the two clusters of inactive PLTP complexes and the specific activity of the active PLTP contribute to the variation in plasma PLTP specific activity.
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Affiliation(s)
- Marian C Cheung
- Division of Metabolism, Endocrinology and Nutrition, Northwest Lipid Metabolism and Diabetes Research Laboratories, Department of Medicine, University of Washington, Seattle, WA 98109-4517, USA
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12
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Masson D, Deckert V, Gautier T, Klein A, Desrumaux C, Viglietta C, Pais de Barros JP, Le Guern N, Grober J, Labbé J, Ménétrier F, Ripoll PJ, Leroux-Coyau M, Jolivet G, Houdebine LM, Lagrost L. Worsening of diet-induced atherosclerosis in a new model of transgenic rabbit expressing the human plasma phospholipid transfer protein. Arterioscler Thromb Vasc Biol 2011; 31:766-74. [PMID: 21252068 DOI: 10.1161/atvbaha.110.215756] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Plasma phospholipid transfer protein (PLTP) is involved in intravascular lipoprotein metabolism. PLTP is known to act through 2 main mechanisms: by remodeling high-density lipoproteins (HDL) and by increasing apolipoprotein (apo) B-containing lipoproteins. The aim of this study was to generate a new model of human PLTP transgenic (HuPLTPTg) rabbit and to determine whether PLTP expression modulates atherosclerosis in this species that, unlike humans and mice, displays naturally very low PLTP activity. METHODS AND RESULTS In HuPLTPTg rabbits, the human PLTP cDNA was placed under the control of the human eF1-α gene promoter, resulting in a widespread tissue expression pattern and in increased plasma PLTP. The HuPLTPTg rabbits showed a significant increase in the cholesterol content of the plasma apoB-containing lipoprotein fractions, with a more severe trait when animals were fed a cholesterol-rich diet. In contrast, HDL cholesterol level was not modified in HuPLTPTg rabbits. Formation of aortic fatty streaks was increased in hypercholesterolemic HuPLTPTg animals as compared with nontransgenic littermates. CONCLUSIONS Human PLTP expression in HuPLTPTg rabbit worsens atherosclerosis as a result of increased levels of atherogenic apoB-containing lipoproteins but not of alterations in their antioxidative protection or in cholesterol content of plasma HDL.
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Affiliation(s)
- David Masson
- Institut National de la Santé et de la Recherche Médicale, Université de Bourgogne, UMR866, Dijon, France
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13
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Cheung MC, Vaisar T, Han X, Heinecke JW, Albers JJ. Phospholipid transfer protein in human plasma associates with proteins linked to immunity and inflammation. Biochemistry 2010; 49:7314-22. [PMID: 20666409 DOI: 10.1021/bi100359f] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phospholipid transfer protein (PLTP), which associates with apolipoprotein A-I (the major HDL protein), plays a key role in lipoprotein remodeling. Because its level in plasma increases during acute inflammation, it may also play previously unsuspected roles in the innate immune system. To gain further insight into its potential physiological functions, we isolated complexes containing PLTP from plasma by immunoaffinity chromatography and determined their composition. Shotgun proteomics revealed that only 6 of the 24 proteins detected in the complexes were apolipoproteins. The most abundant proteins were clusterin (apoJ), PLTP itself, coagulation factors, complement factors, and apoA-I. Remarkably, 20 of the 24 proteins had known protein-protein interactions. Biochemical studies confirmed two previously established interactions and identified five new ones between PLTP and proteins. Moreover, clusterin, apoA-I, and apoE preserved the lipid-transfer activity of recombinant PLTP in the absence of lipid, indicating that these interactions may have functional significance. Unexpectedly, lipids accounted for only 3% of the mass of the PLTP complexes. Collectively, our observations indicate that PLTP in human plasma resides on lipid-poor complexes dominated by clusterin and proteins implicated in host defense and inflammation. They further suggest that protein-protein interactions drive the formation of PLTP complexes in plasma.
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Affiliation(s)
- Marian C Cheung
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, School of Medicine, University of Washington, Seattle, Washington 98109, USA
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Robciuc MR, Metso J, Sima A, Ehnholm C, Jauhiainen M. Human apoA-I increases macrophage foam cell derived PLTP activity without affecting the PLTP mass. Lipids Health Dis 2010; 9:59. [PMID: 20534134 PMCID: PMC2890626 DOI: 10.1186/1476-511x-9-59] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 06/09/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND phospholipid transfer protein (PLTP) plays important roles in lipoprotein metabolism and atherosclerosis and is expressed by macrophages and macrophage foam cells (MFCs). The aim of the present study was to determine whether the major protein from HDL, apoA-I, affects PLTP derived from MFCs. RESULTS as cell model we used human THP-1 monocytes incubated with acetylated LDL, to generate MFC. The addition of apoA-I to the cell media increased apoE secretion from the cells, in a concentration dependent fashion, without affecting cellular apoE levels. In contrast, apoA-I had no effect on PLTP synthesis and secretion, but strongly induced the PLTP activity in the media. ApoA-I also increased phospholipid transfer activity of PLTP isolated from human plasma. This effect was dependent on apoA-I concentration but independent on apoA-I lipidation status. ApoE, ApoA-II and apoA-IV, but not immunoglobulins or bovine serum albumin, also increased PLTP activity. We also report that apoA-I protects PLTP from heat inactivation. CONCLUSION apoA-I enhances the phospholipid transfer activity of PLTP secreted from macrophage foam cells without affecting the PLTP mass.
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Affiliation(s)
- Marius R Robciuc
- National Institute for Health and Welfare, Public Health Genomics Research Unit and FIMM, Institute for Molecular Medicine Finland, Helsinki, Finland.
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15
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Henderson RJ, Leon CG, Wasan KM. Differences in human phospholipid transfer protein activity following incubation of Fungizone compared to lipid-based Amphotericin-B formulations in normolipidemic and hyperlipidemic plasma. Drug Dev Ind Pharm 2010; 35:1139-46. [PMID: 19381990 DOI: 10.1080/03639040902824852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AIM To investigate how different formulations of Amphotericin-B (Amp-B) affect the activity of phospholipid transfer protein (PLTP) when incubated with hyperlipidemic and normolipidemic plasma at physiological temperature (37 degrees C). METHODS Six hyperlipidemic and six normolipidemic plasma samples were collected and tested for protein concentration. Equivalent protein levels (25 microg) were then tested for PLTP activity using an in vitro established kit at physiological temperature (37 degrees C). Increasing concentrations of different Amp-B formulations (1, 2, and 5 microg/mL) in the pharmacological range were then added to the plasma and tested for activity from 5 to 90 minutes. The Amp-B formulations used in the study were Fungizone, Abelcet, and AmBisome. RESULTS In normolipidemic plasma, PLTP activity was found to be increased by Abelcet and AmBisome but inhibited by Fungizone. In hyperlipidemic plasma, PLTP activity was found to be increased by Abelcet and AmBisome but not changed by Fungizone. The Vm value for Abelcet and AmBisome was higher than Fungizone(; although, no difference was observed in the Km values between formulations. CONCLUSIONS Findings suggest that lipid-based formulations of Amp-B promote the transfer of Amp-B into high-density lipoprotein fractions at a degree of increase inversely proportional to the lipid levels in the plasma.
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Affiliation(s)
- Ryan J Henderson
- Division of Pharmaceutics and Biopharmaceutics, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
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16
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Henderson RJ, Wasan KM, Leon CG. Haptoglobin inhibits phospholipid transfer protein activity in hyperlipidemic human plasma. Lipids Health Dis 2009; 8:27. [PMID: 19627602 PMCID: PMC2729738 DOI: 10.1186/1476-511x-8-27] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 07/23/2009] [Indexed: 12/16/2022] Open
Abstract
Background Haptoglobin is a plasma protein that scavenges haemoglobin during haemolysis. Phospholipid Transfer Protein (PLTP) transfers lipids from Low Density Lipoproteins (LDL) to High Density Lipoproteins (HDL). PLTP is involved in the pathogenesis of atherosclerosis which causes coronary artery disease, the leading cause of death in North America. It has been shown that Apolipoprotein-A1 (Apo-A1) binds and regulates PLTP activity. Haptoglobin can also bind to Apo-A1, affecting the ability of Apo-A1 to induce enzymatic activities. Thus we hypothesize that haptoglobin inhibits PLTP activity. This work tested the effect of Haptoglobin and Apo-A1 addition on PLTP activity in human plasma samples. The results will contribute to our understanding of the role of haptoglobin on modulating reverse cholesterol transport. Results We analyzed the PLTP activity and Apo-A1 and Haptoglobin content in six hyperlipidemic and six normolipidemic plasmas. We found that Apo-A1 levels are proportional to PLTP activity in hyperlipidemic (R2 = 0.66, p < 0.05) but not in normolipidemic human plasma. Haptoglobin levels and PLTP activity are inversely proportional in hyperlipidemic plasmas (R2 = 0.57, p > 0.05). When the PLTP activity was graphed versus the Hp/Apo-A1 ratio in hyperlipidemic plasma there was a significant correlation (R2 = 0.69, p < 0.05) suggesting that PLTP activity is affected by the combined effect of Apo-A1 and haptoglobin. When haptoglobin was added to individual hyperlipidemic plasma samples there was a dose dependent decrease in PLTP activity. In these samples we also found a negative correlation (-0.59, p < 0.05) between PLTP activity and Hp/Apo-A1. When we added an amount of haptoglobin equivalent to 100% of the basal levels, we found a 64 ± 23% decrease (p < 0.05) in PLTP activity compared to basal PLTP activity. We tested the hypothesis that additional Apo-A1 would induce PLTP activity. Interestingly we found a dose dependent decrease in PLTP activity upon Apo-A1 addition. When both Apo-A1 and Hpt were added to the plasma samples there was no further reduction in PLTP activity suggesting that they act through a common pathway. Conclusion These findings suggest an inhibitory effect of Haptoglobin over PLTP activity in hyperlipidemic plasma that may contribute to the regulation of reverse cholesterol transport.
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Affiliation(s)
- Ryan J Henderson
- Division of Pharmaceutics and Biopharmaceutics, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T1Z3, Canada.
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Tzotzas T, Desrumaux C, Lagrost L. Plasma phospholipid transfer protein (PLTP): review of an emerging cardiometabolic risk factor. Obes Rev 2009; 10:403-11. [PMID: 19413703 DOI: 10.1111/j.1467-789x.2009.00586.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Plasma phospholipid transfer protein (PLTP) is a lipid transfer glycoprotein that binds to and transfers a number of amphipathic compounds. In earlier studies, the attention of the scientific community focused on the positive role of PLTP in high-density lipoprotein (HDL) metabolism. However, this potentially anti-atherogenic role of PLTP has been challenged recently by another picture: PLTP arose as a pro-atherogenic factor through its ability to increase the production of apolipoprotein B-containing lipoproteins, to decrease their antioxidative protection and to trigger inflammation. In humans, PLTP has mostly been studied in patients with cardiometabolic disorders. Both PLTP and related cholesteryl ester transfer protein (CETP) are secreted proteins, and adipose tissue is an important contributor to the systemic pools of these two proteins. Coincidently, high levels of PLTP and CETP have been found in the plasma of obese patients. PLTP activity and mass have been reported to be abnormally elevated in type 2 diabetes mellitus (T2DM) and insulin-resistant states, and this elevation is frequently associated with hypertriglyceridemia and obesity. This review article presents the state of knowledge on the implication of PLTP in lipoprotein metabolism, on its atherogenic potential, and the complexity of its implication in obesity, insulin resistance and T2DM.
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Affiliation(s)
- T Tzotzas
- Department of Nutrition and Dietetics, Technological Educational Institution, Thessaloniki, Greece.
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18
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Moriarty PM. Association of ApoE and HDL-C with cardiovascular and cerebrovascular disease: potential benefits of LDL-apheresis therapy. ACTA ACUST UNITED AC 2009. [DOI: 10.2217/clp.09.21] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vuletic S, Dong W, Wolfbauer G, Day JR, Albers JJ. PLTP is present in the nucleus, and its nuclear export is CRM1-dependent. BIOCHIMICA ET BIOPHYSICA ACTA 2009; 1793:584-91. [PMID: 19321130 PMCID: PMC2692677 DOI: 10.1016/j.bbamcr.2009.01.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 12/09/2008] [Accepted: 01/05/2009] [Indexed: 12/23/2022]
Abstract
Phospholipid transfer protein (PLTP), one of the key lipid transfer proteins in plasma and cerebrospinal fluid, is nearly ubiquitously expressed in cells and tissues. Functions of secreted PLTP have been extensively studied. However, very little is known about potential intracellular PLTP functions. In the current study, we provide evidence for PLTP localization in the nucleus of cells that constitutively express PLTP (human neuroblastoma cells, SK-N-SH; and human cortical neurons, HCN2) and in cells transfected with human PLTP (Chinese hamster ovary and baby hamster kidney cells). Furthermore, we have shown that incubation of these cells with leptomycin B (LMB), a specific inhibitor of nuclear export mediated by chromosome region maintenance 1 (CRM1), leads to intranuclear accumulation of PLTP, suggesting that PLTP nuclear export is CRM1-dependent. We also provide evidence for entry of secreted PLTP into the cell and its translocation to the nucleus, and show that intranuclear PLTP is active in phospholipid transfer. These findings suggest that PLTP is involved in novel intracellular functions.
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Affiliation(s)
- Simona Vuletic
- Department of Medicine, Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA
| | - Weijiang Dong
- Department of Medicine, Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA
- Xi’an Jiaotong University School of Medicine, Department of Human Anatomy and Histology & Embryology, Yanta West Road 76, Xi’an 710061, People’s Republic of China
| | - Gertrud Wolfbauer
- Department of Medicine, Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA
| | - Joseph R. Day
- Department of Medicine, Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA
| | - John J. Albers
- Department of Medicine, Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA
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Cheung MC, Wolfbauer G, Deguchi H, Fernández JA, Griffin JH, Albers JJ. Human plasma phospholipid transfer protein specific activity is correlated with HDL size: implications for lipoprotein physiology. Biochim Biophys Acta Mol Cell Biol Lipids 2008; 1791:206-11. [PMID: 19162221 DOI: 10.1016/j.bbalip.2008.12.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 12/09/2008] [Accepted: 12/18/2008] [Indexed: 11/20/2022]
Abstract
To gain further insights into the relationship between plasma phospholipid transfer protein (PLTP) and lipoprotein particles, PLTP mass and phospholipid transfer activity were measured, and their associations with the level and size of lipoprotein particles examined in 39 healthy adult subjects. No bivariate correlation was observed between PLTP activity and mass. PLTP activity was positively associated with cholesterol, triglyceride, apo B and VLDL particle level (r(s)=0.40-0.56, p< or =0.01) while PLTP mass was positively associated with HDL-C, large HDL particles, and mean LDL and HDL particle sizes (r(s)=0.44-0.52, p<0.01). Importantly, plasma PLTP specific activity (SA) was significantly associated with specific lipoprotein classes, positively with VLDL, IDL, and small LDL particles (r(s)=0.42-0.62, p< or =0.01) and inversely with large LDL, large HDL, and mean LDL and HDL particle size (r(s)=-0.42 to -0.70, p< or =0.01). After controlling for triglyceride levels, the correlation between PLTP mass or SA and HDL size remained significant. In linear models, HDL size explained 45% of the variability of plasma PLTP SA while triglyceride explained 34% of the PLTP activity. Thus, in healthy adults a significant relationship exists between HDL size and plasma PLTP SA (r(s)=-0.70), implying that HDL particle size may modulate PLTP SA in the vascular compartment.
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Affiliation(s)
- Marian C Cheung
- Department of Medicine, University of Washington, Seattle, WA 98109-4517, USA
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21
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Vergeer M, Dallinga-Thie GM, Dullaart RPF, van Tol A. Evaluation of phospholipid transfer protein as a therapeutic target. ACTA ACUST UNITED AC 2008. [DOI: 10.2217/17460875.3.3.327] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Settasatian N, Barter PJ, Rye KA. Remodeling of apolipoprotein E-containing spherical reconstituted high density lipoproteins by phospholipid transfer protein. J Lipid Res 2008; 49:115-26. [DOI: 10.1194/jlr.m700220-jlr200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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23
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Schgoer W, Mueller T, Jauhiainen M, Wehinger A, Gander R, Tancevski I, Salzmann K, Eller P, Ritsch A, Haltmayer M, Ehnholm C, Patsch JR, Foeger B. Low phospholipid transfer protein (PLTP) is a risk factor for peripheral atherosclerosis. Atherosclerosis 2007; 196:219-226. [PMID: 17553507 DOI: 10.1016/j.atherosclerosis.2007.04.046] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Revised: 04/18/2007] [Accepted: 04/27/2007] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Phospholipid transfer protein (PLTP) facilitates cholesterol efflux from cells, intravascular HDL remodelling and transfer of vitamin E and endotoxin. In humans, the relationship of PLTP to atherosclerosis is unknown. However, strong coronary risk factors like obesity, diabetes, cigarette smoking and inflammation increase circulating levels of active PLTP. The aim of the present, cross-sectional study was to analyze the relationship of PLTP to peripheral arterial disease, a marker of generalized atherosclerosis, independently of potentially confounding factors like obesity, diabetes and smoking. METHODS We performed a case control study in 153 patients with symptomatic peripheral arterial disease (PAD) and 208 controls free of vascular disease. Smokers and patients with diabetes mellitus were excluded. A lipoprotein-independent assay was used for measurement of circulating bioactive PLTP and an ELISA utilizing a monoclonal antibody was used to analyze PLTP mass. RESULTS PLTP activity was significantly decreased in patients with PAD 5.5 (4.6-6.4)(median (25th-75th percentile)) versus 5.9 (5.1-6.9) micromol/mL/h in controls (p=0.001). In contrast, PLTP mass was similar in patients with PAD 8.5 microg/mL (7.3-9.5) and in controls 8.3 microg/mL (6.9-9.7) (p=0.665). Multivariate logistic regression analysis revealed that PLTP activity is independently associated with the presence of PAD. PLTP activity was similar in patients with and without lipid-lowering drugs (p=0.396). CONCLUSION Our results show that in non-diabetic, non-smoking subjects low rather than high PLTP activity is a marker for the presence of peripheral arterial disease and that distribution of PLTP between high-activity and low-activity forms may be compromised in atherosclerosis.
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Affiliation(s)
- Wilfried Schgoer
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Thomas Mueller
- Department of Laboratory Medicine, Konventhospital Barmherzige Brueder, Linz, Austria
| | - Matti Jauhiainen
- Department of Molecular Medicine, National Public Health Institute, Biomedicum, Helsinki, Finland
| | - Andreas Wehinger
- Department of Internal Medicine, Medical University Innsbruck, Austria; Department of Internal Medicine, Landeskrankenhaus Bregenz, Austria
| | - Roland Gander
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Ivan Tancevski
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Karin Salzmann
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Philipp Eller
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Andreas Ritsch
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Meinhard Haltmayer
- Department of Laboratory Medicine, Konventhospital Barmherzige Brueder, Linz, Austria
| | - Christian Ehnholm
- Department of Molecular Medicine, National Public Health Institute, Biomedicum, Helsinki, Finland
| | - Josef R Patsch
- Department of Internal Medicine, Medical University Innsbruck, Austria
| | - Bernhard Foeger
- Department of Internal Medicine, Medical University Innsbruck, Austria; Department of Internal Medicine, Landeskrankenhaus Bregenz, Austria.
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Dallinga-Thie GM, Dullaart RPF, van Tol A. Concerted actions of cholesteryl ester transfer protein and phospholipid transfer protein in type 2 diabetes: effects of apolipoproteins. Curr Opin Lipidol 2007; 18:251-7. [PMID: 17495597 DOI: 10.1097/mol.0b013e3280e12685] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Type 2 diabetes frequently coincides with dyslipidemia, characterized by elevated plasma triglycerides, low high-density lipoprotein cholesterol levels and the presence of small dense low-density lipoprotein particles. Plasma lipid transfer proteins play an essential role in lipoprotein metabolism. It is thus vital to understand their pathophysiology and determine which factors influence their functioning in type 2 diabetes. RECENT FINDINGS Cholesteryl ester transfer protein-mediated transfer is increased in diabetic patients and contributes to low plasma high-density lipoprotein cholesterol levels. Apolipoproteins A-I, A-II and E are components of the donor lipoprotein particles that participate in the transfer of cholesteryl esters from high-density lipoprotein to apolipoprotein B-containing lipoproteins. Current evidence for functional roles of apolipoproteins C-I, F and A-IV as modulators of cholesteryl ester transfer is discussed. Phospholipid transfer protein activity is increased in diabetic patients and may contribute to hepatic very low-density lipoprotein synthesis and secretion and vitamin E transfer. Apolipoprotein E could stimulate the phospholipid transfer protein-mediated transfer of surface fragments of triglyceride-rich lipoproteins to high-density lipoprotein, and promote high-density lipoprotein remodelling. SUMMARY Both phospholipid and cholesteryl ester transfer proteins are important in very low and high-density lipoprotein metabolism and display concerted actions in patients with type 2 diabetes.
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Affiliation(s)
- Geesje M Dallinga-Thie
- Department of Vascular Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands.
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25
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Affiliation(s)
- David Akopian
- Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, California 91330-8262, USA
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Liu R, Hojjati MR, Devlin CM, Hansen IH, Jiang XC. Macrophage phospholipid transfer protein deficiency and ApoE secretion: impact on mouse plasma cholesterol levels and atherosclerosis. Arterioscler Thromb Vasc Biol 2006; 27:190-6. [PMID: 17038631 DOI: 10.1161/01.atv.0000249721.96666.e5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE PLTP and apoE play important roles in lipoprotein metabolism and atherosclerosis. It is known that formation of macrophage-derived foam cells (which highly express PLTP and apoE) is the critical step in the process of atherosclerosis. We investigated the relationship between PLTP and apoE in macrophages and the atherogenic relevance in a mouse model. METHODS AND RESULTS We transplanted PLTP-deficient mouse bone marrow into apoE-deficient mice (PLTP-/- --> apoE-/-), creating a mouse model with PLTP deficiency and apoE expression exclusively in the macrophages. We found that PLTP-/- --> apoE-/- mice have significantly lower PLTP activity, compared with controls (WT --> apoE-/-; 20%, P<0.01). On a Western diet, PLTP-/- --> apoE-/- mice have significantly lower plasma apoE than that of WT --> apoE-/- mice (63%, P<0.001), and PLTP-deficient macrophages secrete significantly less apoE than WT macrophages (44%, P<0.01). Moreover, PLTP-/- --> apoE-/- mice have significantly higher plasma cholesterol (98%, P<0.001) and phospholipid (107%, P<0.001) than that of WT --> apoE-/- mice, thus increasing atherosclerotic lesions in the aortic arch and root (403%, P<0.001), as well as the entire aorta (298%, P<0.001). CONCLUSIONS Macrophage PLTP deficiency causes a significant reduction of apoE secretion from the cells, and this in turn promotes the accumulation of cholesterol in the circulation and accelerates the development of atherosclerosis.
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Affiliation(s)
- Ruijie Liu
- Department of Anatomy and Cell Biology, SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY 11203, USA
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