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Bridgeman S, Woo HC, Newsholme P, Mamotte C. Butyrate Lowers Cellular Cholesterol through HDAC Inhibition and Impaired SREBP-2 Signalling. Int J Mol Sci 2022; 23. [PMID: 36555149 DOI: 10.3390/ijms232415506] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/25/2022] [Accepted: 11/30/2022] [Indexed: 12/13/2022] Open
Abstract
In animal studies, HDAC inhibitors such as butyrate have been reported to reduce plasma cholesterol, while conferring protection from diabetes, but studies on the underlying mechanisms are lacking. This study compares the influence of butyrate and other HDAC inhibitors to that of statins on cholesterol metabolism in multiple cell lines, but primarily in HepG2 hepatic cells due to the importance of the liver in cholesterol metabolism. Sodium butyrate reduced HepG2 cholesterol content, as did sodium valproate and the potent HDAC inhibitor trichostatin A, suggesting HDAC inhibition as the exacting mechanism. In contrast to statins, which increase SREBP-2 regulated processes, HDAC inhibition downregulated SREBP-2 targets such as HMGCR and the LDL receptor. Moreover, in contrast to statin treatment, butyrate did not increase cholesterol uptake by HepG2 cells, consistent with its failure to increase LDL receptor expression. Sodium butyrate also reduced ABCA1 and SRB1 protein expression in HepG2 cells, but these effects were not consistent across all cell types. Overall, the underlying mechanism of cell cholesterol lowering by sodium butyrate and HDAC inhibition is consistent with impaired SREBP-2 signalling, and calls into question the possible use of butyrate for lowering of serum LDL cholesterol in humans.
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Hu S, Hu D, Wei H, Li SY, Wang D, Li CZ, Jiang J, Wang D, Cui G, Wang D. Functional Deletion/Insertion Promoter Variants in SCARB1 Associated With Increased Susceptibility to Lipid Profile Abnormalities and Coronary Heart Disease. Front Cardiovasc Med 2022; 8:800873. [PMID: 35097019 PMCID: PMC8793335 DOI: 10.3389/fcvm.2021.800873] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 12/20/2021] [Indexed: 12/12/2022] Open
Abstract
Background: Genetic variants in Scavenger receptor Class B Type 1 (SCARB1) influencing high-density lipoprotein cholesterol (HDL-C) and coronary heart disease (CHD) risk were identified by recent genome-wide association studies. Further study of potential functional variants in SCARB1 may provide new ideas of the complicated relationship between HDL-C and CHD. Methods: 2000 bp in SCARB1 promoter region was re-sequenced in 168 participants with extremely high plasma HDL-C and 400 control subjects. Putative risk alleles were identified using bioinformatics analysis and reporter-gene assays. Two indel variants, rs144334493 and rs557348251, respectively, were genotyped in 5,002 CHD patients and 5,175 control subjects. The underlying mechanisms were investigated. Results: Through resequencing, 27 genetic variants were identified. Results of genotyping in 5,002 CHD patients and 5,175 control subjects revealed that rs144334493 and rs557348251 were significantly associated with increased risk of CHD [odds ratio (OR): 1.28, 95% confidence interval (CI): 1.09 to 1.52, p = 0.003; OR: 2.65, 95% CI: 1.66–4.24, p = 4.4 × 10−5). Subsequent mechanism experiments demonstrated that rs144334493 deletion allele attenuated forkhead box A1 (FOXA1) binding to the promoter region of SCARB1, while FOXA1 overexpression reversely increased SR-BI expression. Conclusion: Genetic variants in SCARB1 promoter region significantly associated with the plasma lipid levels by affecting SR-BI expression and contribute to the susceptibility of CHD.
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Affiliation(s)
- Senlin Hu
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Dong Hu
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Haoran Wei
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Shi-yang Li
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Dong Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Chen-ze Li
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Jiangang Jiang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Daowen Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
| | - Guanglin Cui
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Guanglin Cui
| | - Daowu Wang
- State Key Laboratory of Reproductive Medicine, The Center for Clinical Reproductive Medicine and Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- Daowu Wang
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3
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Abstract
PURPOSE OF REVIEW The binding of high-density lipoprotein (HDL) to its primary receptor, scavenger receptor class B type 1 (SR-B1), is critical for lowering plasma cholesterol levels and reducing cardiovascular disease risk. This review provides novel insights into how the structural elements of SR-B1 drive efficient function with an emphasis on bidirectional cholesterol transport. RECENT FINDINGS We have generated a new homology model of full-length human SR-B1 based on the recent resolution of the partial structures of other class B scavenger receptors. Interrogating this model against previously published observations allows us to generate structurally informed hypotheses about SR-B1's ability to mediate HDL-cholesterol (HDL-C) transport. Furthermore, we provide a structural perspective as to why human variants of SR-B1 may result in impaired HDL-C clearance. A comprehensive understanding of SR-B1's structure-function relationships is critical to the development of therapeutic agents targeting SR-B1 and modulating cardiovascular disease risk.
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Affiliation(s)
- Hayley R. Powers
- grid.30760.320000 0001 2111 8460Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI USA
| | - Daisy Sahoo
- grid.30760.320000 0001 2111 8460Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI USA ,grid.30760.320000 0001 2111 8460Department of Medicine, Division of Endocrinology & Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI USA ,grid.30760.320000 0001 2111 8460Cardiovascular Center, H4930 Health Research Center, Medical College of Wisconsin, 8701 W. Watertown Plank Road, Milwaukee, WI 53226 USA
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4
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Lian J, van der Veen JN, Watts R, Jacobs RL, Lehner R. Carboxylesterase 1d (Ces1d) does not contribute to cholesteryl ester hydrolysis in the liver. J Lipid Res 2021; 62:100093. [PMID: 34153284 PMCID: PMC8287225 DOI: 10.1016/j.jlr.2021.100093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 06/09/2021] [Indexed: 01/19/2023] Open
Abstract
The liver is the central organ regulating cholesterol synthesis, storage, transport, and elimination. Mouse carboxylesterase 1d (Ces1d) and its human ortholog CES1 have been described to possess lipase activity and play roles in hepatic triacylglycerol metabolism and VLDL assembly. It has been proposed that Ces1d/CES1 might also catalyze cholesteryl ester (CE) hydrolysis in the liver and thus be responsible for the hydrolysis of HDL-derived CE; this could contribute to the final step in the reverse cholesterol transport (RCT) pathway, wherein cholesterol is secreted from the liver into bile and feces, either directly or after conversion to water-soluble bile salts. However, the proposed function of Ces1d/CES1 as a CE hydrolase is controversial. In this study, we interrogated the role hepatic Ces1d plays in cholesterol homeostasis using liver-specific Ces1d-deficient mice. We rationalized that if Ces1d is a major hepatic CE hydrolase, its absence would (1) reduce in vivo RCT flux and (2) provoke liver CE accumulation after a high-cholesterol diet challenge. We found that liver-specific Ces1d-deficient mice did not show any difference in the flux of in vivo HDL-to-feces RCT nor did it cause additional liver CE accumulation after high-fat, high-cholesterol Western-type diet feeding. These findings challenge the importance of Ces1d as a major hepatic CE hydrolase.
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Affiliation(s)
- Jihong Lian
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.
| | - Jelske N van der Veen
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada; Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Russell Watts
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - René L Jacobs
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada; Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Richard Lehner
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada; Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada.
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5
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Feriani A, Tir M, Hachani R, Allagui MS, Tlili N, Nahdi S, Alwasel S, Harrath AH. Permethrin induced arterial retention of native and oxidized LDL in rats by promoting inflammation, oxidative stress and affecting LDL receptors, and collagen genes. Ecotoxicol Environ Saf 2021; 207:111269. [PMID: 32911180 DOI: 10.1016/j.ecoenv.2020.111269] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 06/11/2023]
Abstract
This study is the first to examine the possible mechanism by which long-term exposure to permethrin (PER) can promote arterial retention of proatherogenic lipid and lipoproteins and related vascular dysfunction in rats. Experimental animals were administered two doses of oral PER, PER-1 (2.5 mg/kg/bw) and PER-2 (5 mg/kg/bw), for 90 consecutive days. The results indicated that both PER-1 and PER-2 increased plasmatic and aortic total cholesterol, low-density lipoprotein cholesterol (LDL-C), apo B-100, and oxidized LDL together with arterial scavenger LDL receptors (CD36) but markedly reduced plasmatic and hepatic high-density lipoprotein cholesterol and native LDL receptors in aortic and hepatic tissue. The levels of malondialdehyde, protein carbonyl, and reactive oxygen species were significantly higher, and glutathione content as well as catalase, superoxide dismutase, and glutathione peroxidase activities were suppressed in the aorta of the PER-1 and PER-2 groups. The arterial oxidative damage possibly caused by PER was clearly demonstrated by hematoxylin and eosin histological analysis. Moreover, PER treatment aggravated the inflammatory responses through enhancement of the production of proinflammatory cytokines (tumor necrosis factor-α, interleukin-2, and interleukin-6) in both plasma and aorta. Furthermore, PER-1 and PER-2 potentiated the dysregulation of the aortic extracellular matrix (ECM) content by increasing mRNA activation of collagens I and III. The abundant histological collagen deposition observed in the media and adventitia of intoxicated rats using Masson's trichrome staining corroborates the observed change in ECM. These data showed that oxidative stress related to PER exposure increases the arterial accumulation of lipoprotein biomarkers, likely by actions on both LDL and CD36 receptors, together with the disruption of the aortic ECM.
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Affiliation(s)
- Anouar Feriani
- Research Unit of Macromolecular Biochemistry and Genetics, Faculty of Sciences of Gafsa, 2112, Gafsa, Tunisia
| | - Meriam Tir
- Laboratoire des Sciences de L'Environnement, Biologie et Physiologie des Organismes Aquatiques, LR18ES41, Faculté des Sciences de Tunis, Université Tunis EL Manar, 2092, Tunis, Tunisia
| | - Rafik Hachani
- Université de Carthage, Unité de Physiologie Intégrée, Laboratoire de Pathologies Vasculaires, Faculté des Sciences de Bizerte, 7021, Jarzouna, Tunisia; Laboratoire D'Etude de La Microcirculation (EA 3509), Faculté de Médecine Lariboisière-St. Louis, Université Paris VII, France
| | | | - Nizar Tlili
- Institut Supérieur des Sciences et Technologies de L'Environnement, Université de Carthage, Tunisia
| | - Saber Nahdi
- King Saud University, Department of Zoology, College of Science, Riyadh, 11451, Saudi Arabia
| | - Saleh Alwasel
- King Saud University, Department of Zoology, College of Science, Riyadh, 11451, Saudi Arabia.
| | - Abdel Halim Harrath
- King Saud University, Department of Zoology, College of Science, Riyadh, 11451, Saudi Arabia; University of Tunis El Manar, Higher Institute of Applied Biological Sciences of Tunis, 2092, Tunis, Tunisia.
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6
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Xu Y, Li Y, Jadhav K, Pan X, Zhu Y, Hu S, Chen S, Chen L, Tang Y, Wang HH, Yang L, Wang DQH, Yin L, Zhang Y. Hepatocyte ATF3 protects against atherosclerosis by regulating HDL and bile acid metabolism. Nat Metab 2021; 3:59-74. [PMID: 33462514 PMCID: PMC7856821 DOI: 10.1038/s42255-020-00331-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 12/09/2020] [Indexed: 12/13/2022]
Abstract
Activating transcription factor (ATF)3 is known to have an anti-inflammatory function, yet the role of hepatic ATF3 in lipoprotein metabolism or atherosclerosis remains unknown. Here we show that overexpression of human ATF3 in hepatocytes reduces the development of atherosclerosis in Western-diet-fed Ldlr-/- or Apoe-/- mice, whereas hepatocyte-specific ablation of Atf3 has the opposite effect. We further show that hepatic ATF3 expression is inhibited by hydrocortisone. Mechanistically, hepatocyte ATF3 enhances high-density lipoprotein (HDL) uptake, inhibits intestinal fat and cholesterol absorption and promotes macrophage reverse cholesterol transport by inducing scavenger receptor group B type 1 (SR-BI) and repressing cholesterol 12α-hydroxylase (CYP8B1) in the liver through its interaction with p53 and hepatocyte nuclear factor 4α, respectively. Our data demonstrate that hepatocyte ATF3 is a key regulator of HDL and bile acid metabolism and atherosclerosis.
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Affiliation(s)
- Yanyong Xu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Yuanyuan Li
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Zhongshan Institute for Drug Discovery, the Institutes of Drug Discovery and Development, Chinese Academy of Sciences, Zhongshan, China
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Kavita Jadhav
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Xiaoli Pan
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yingdong Zhu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Shuwei Hu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Shaoru Chen
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Liuying Chen
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yong Tang
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Helen H Wang
- Department of Medicine and Genetics, Marion Bessin Liver Research Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ling Yang
- Divison of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - David Q-H Wang
- Department of Medicine and Genetics, Marion Bessin Liver Research Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Liya Yin
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Yanqiao Zhang
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA.
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7
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Abstract
Atherosclerotic plaques impair vascular function and can lead to arterial obstruction and tissue ischaemia. Rupture of an atherosclerotic plaque within a coronary artery can result in an acute myocardial infarction, which is responsible for significant morbidity and mortality worldwide. Prompt reperfusion can salvage some of the ischaemic territory, but ischaemia and reperfusion (IR) still causes substantial injury and is, therefore, a therapeutic target for further infarct limitation. Numerous cardioprotective strategies have been identified that can limit IR injury in animal models, but none have yet been translated effectively to patients. This disconnect prompts an urgent re-examination of the experimental models used to study IR. Since coronary atherosclerosis is the most prevalent morbidity in this patient population, and impairs coronary vessel function, it is potentially a major confounder in cardioprotective studies. Surprisingly, most studies suggest that atherosclerosis does not have a major impact on cardioprotection in mouse models. However, a major limitation of atherosclerotic animal models is that the plaques usually manifest in the aorta and proximal great vessels, and rarely in the coronary vessels. In this review, we examine the commonly used mouse models of atherosclerosis and their effect on coronary artery function and infarct size. We conclude that none of the commonly used strains of mice are ideal for this purpose; however, more recently developed mouse models of atherosclerosis fulfil the requirement for coronary artery lesions, plaque rupture and lipoprotein patterns resembling the human profile, and may enable the identification of therapeutic interventions more applicable in the clinical setting.
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MESH Headings
- Animals
- Aortic Diseases/complications
- Aortic Diseases/genetics
- Aortic Diseases/metabolism
- Aortic Diseases/pathology
- Atherosclerosis/complications
- Atherosclerosis/genetics
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Coronary Artery Disease/complications
- Coronary Artery Disease/genetics
- Coronary Artery Disease/metabolism
- Coronary Artery Disease/pathology
- Diet, High-Fat
- Disease Models, Animal
- Genetic Predisposition to Disease
- Mice, Knockout, ApoE
- Myocardial Infarction/etiology
- Myocardial Infarction/genetics
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardium/pathology
- Phenotype
- Plaque, Atherosclerotic
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
- Rupture, Spontaneous
- Scavenger Receptors, Class B/deficiency
- Scavenger Receptors, Class B/genetics
- Species Specificity
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Affiliation(s)
- Pelin Golforoush
- The Hatter Cardiovascular Institute, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Derek M Yellon
- The Hatter Cardiovascular Institute, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Sean M Davidson
- The Hatter Cardiovascular Institute, 67 Chenies Mews, London, WC1E 6HX, UK.
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8
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Liu J, Zhao M, Zhu Y, Zheng L, Yin Y. Plasma Metabolomic and Lipidomic Profiling of a Genetically Modified Mouse Model of Scavenger Receptor Class B Type I. Proteomics 2020; 20:e2000050. [PMID: 33090674 DOI: 10.1002/pmic.202000050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 08/31/2020] [Indexed: 11/06/2022]
Abstract
Atherosclerosis is a chronic inflammatory disease of the arterial wall and is becoming the principal cause of death globally. The reverse cholesterol transport (RCT) mediated by scavenger receptor class B type I (SR-BI) is a major protection mechanism against atherosclerosis. To investigate the metabolome changes and to find potential biomarkers involved in RCT, nontargeted metabolomics and nontargeted lipidomics are applied to SR-BI knockout mice that are fed a high fat and high cholesterol diet. SR-BI knockout mice and controls are told apart using multidimensional statistical analysis, and potential biomarkers are found and identified. The pathophysiological meaning of the biomarkers and the perturbed metabolic pathways are also addressed, which could provide new evidence for atherosclerosis studies.
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Affiliation(s)
- Jia Liu
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Mingming Zhao
- The Institute of Cardiovascular Sciences, School of Basic Medical Sciences, and Key Laboratory of Molecular Cardiovascular Sciences of Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Yizhang Zhu
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Lemin Zheng
- The Institute of Cardiovascular Sciences, School of Basic Medical Sciences, and Key Laboratory of Molecular Cardiovascular Sciences of Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Yuxin Yin
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, 100191, China
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9
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Palmisano BT, Anozie U, Yu S, Neuman JC, Zhu L, Edington EM, Luu T, Stafford JM. Cholesteryl Ester Transfer Protein Impairs Triglyceride Clearance via Androgen Receptor in Male Mice. Lipids 2020; 56:17-29. [PMID: 32783209 PMCID: PMC7818496 DOI: 10.1002/lipd.12271] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 05/26/2020] [Accepted: 06/30/2020] [Indexed: 12/27/2022]
Abstract
Elevated postprandial triacylglycerols (TAG) are an important risk factor for cardiovascular disease. Men have higher plasma TAG and impaired TAG clearance compared to women, which may contribute to sex differences in risk of cardiovascular disease. Understanding mechanisms of sex differences in TAG metabolism may yield novel therapeutic targets to prevent cardiovascular disease. Cholesteryl ester transfer protein (CETP) is a lipid shuttling protein known for its effects on high‐density lipoprotein (HDL) cholesterol levels. Although mice lack CETP, we previously demonstrated that transgenic CETP expression in female mice alters TAG metabolism. The impact of CETP on TAG metabolism in males, however, is not well understood. Here, we demonstrate that CETP expression increases plasma TAG in males, especially in very‐low density lipoprotein (VLDL), by impairing postprandial plasma TAG clearance compared to wild‐type (WT) males. Gonadal hormones were required for CETP to impair TAG clearance, suggesting a role for sex hormones for this effect. Testosterone replacement in the setting of gonadectomy was sufficient to restore the effect of CETP on TAG. Lastly, liver androgen receptor (AR) was required for CETP to increase plasma TAG. Thus, expression of CETP in males raises plasma TAG by impairing TAG clearance via testosterone signaling to AR. Further understanding of how CETP and androgen signaling impair TAG clearance may lead to novel approaches to reduce TAG and mitigate risk of cardiovascular disease.
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Affiliation(s)
- Brian T Palmisano
- Tennessee Valley Health System, Veterans Affairs, Nashville, TN, USA.,Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA.,Division of Cardiovascular Medicine, Stanford University Medical Center, Stanford, CA, USA
| | - Uche Anozie
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
| | - Sophia Yu
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
| | - Joshua C Neuman
- Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Lin Zhu
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
| | - Emery M Edington
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
| | - Thao Luu
- Tennessee Valley Health System, Veterans Affairs, Nashville, TN, USA.,Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
| | - John M Stafford
- Tennessee Valley Health System, Veterans Affairs, Nashville, TN, USA.,Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA.,Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, 2213 Garland Ave., Nashville, TN, 37232, USA
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10
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Bashore AC, Liu M, Key CCC, Boudyguina E, Wang X, Carroll CM, Sawyer JK, Mullick AE, Lee RG, Macauley SL, Parks JS. Targeted Deletion of Hepatocyte Abca1 Increases Plasma HDL (High-Density Lipoprotein) Reverse Cholesterol Transport via the LDL (Low-Density Lipoprotein) Receptor. Arterioscler Thromb Vasc Biol 2019; 39:1747-1761. [PMID: 31167565 DOI: 10.1161/atvbaha.119.312382] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE The role of hepatocyte Abca1 (ATP binding cassette transporter A1) in trafficking hepatic free cholesterol (FC) into plasma versus bile for reverse cholesterol transport (RCT) is poorly understood. We hypothesized that hepatocyte Abca1 recycles plasma HDL-C (high-density lipoprotein cholesterol) taken up by the liver back into plasma, maintaining the plasma HDL-C pool, and decreasing HDL-mediated RCT into feces. Approach and Results: Chow-fed hepatocyte-specific Abca1 knockout (HSKO) and control mice were injected with human HDL radiolabeled with 125I-tyramine cellobiose (125I-TC; protein) and 3H-cholesteryl oleate (3H-CO). 125I-TC and 3H-CO plasma decay, plasma HDL 3H-CO selective clearance (ie, 3H-125I fractional catabolic rate), liver radiolabel uptake, and fecal 3H-sterol were significantly greater in HSKO versus control mice, supporting increased plasma HDL RCT. Twenty-four hours after 3H-CO-HDL injection, HSKO mice had reduced total hepatic 3H-FC (ie, 3H-CO hydrolyzed to 3H-FC in liver) resecretion into plasma, demonstrating Abca1 recycled HDL-derived hepatic 3H-FC back into plasma. Despite similar liver LDLr (low-density lipoprotein receptor) expression between genotypes, HSKO mice treated with LDLr-targeting versus control antisense oligonucleotide had slower plasma 3H-CO-HDL decay, reduced selective 3H-CO clearance, and decreased fecal 3H-sterol excretion that was indistinguishable from control mice. Increased RCT in HSKO mice was selective for 3H-CO-HDL, since macrophage RCT was similar between genotypes. CONCLUSIONS Hepatocyte Abca1 deletion unmasks a novel and selective FC trafficking pathway that requires LDLr expression, accelerating plasma HDL-selective CE uptake by the liver and promoting HDL RCT into feces, consequently reducing HDL-derived hepatic FC recycling into plasma.
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Affiliation(s)
- Alexander C Bashore
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Mingxia Liu
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Chia-Chi C Key
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Elena Boudyguina
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Xianfeng Wang
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Caitlin M Carroll
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine (C.M.C., S.L.M.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Janet K Sawyer
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Adam E Mullick
- Cardiovascular, Renal and Metabolic Group, Department of Antisense Drug Discovery, Ionis Pharmaceuticals, Inc, Carlsbad, CA (A.E.M., R.G.L.)
| | - Richard G Lee
- Cardiovascular, Renal and Metabolic Group, Department of Antisense Drug Discovery, Ionis Pharmaceuticals, Inc, Carlsbad, CA (A.E.M., R.G.L.)
| | - Shannon L Macauley
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine (C.M.C., S.L.M.), Wake Forest School of Medicine, Winston-Salem, NC
| | - John S Parks
- From the Department of Internal Medicine, Section of Molecular Medicine (A.C.B., M.L., C-C.C.K., E.B., X.W., J.K.S., J.S.P.), Wake Forest School of Medicine, Winston-Salem, NC
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McCormick SPA, Schneider WJ. Lipoprotein(a) catabolism: a case of multiple receptors. Pathology 2018; 51:155-164. [PMID: 30595508 DOI: 10.1016/j.pathol.2018.11.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 10/31/2018] [Accepted: 11/01/2018] [Indexed: 01/09/2023]
Abstract
Lipoprotein(a) [Lp(a)] is an apolipoprotein B (apoB)-containing plasma lipoprotein similar in structure to low-density lipoprotein (LDL). Lp(a) is more complex than LDL due to the presence of apolipoprotein(a) [apo(a)], a large glycoprotein sharing extensive homology with plasminogen, which confers some unique properties onto Lp(a) particles. ApoB and apo(a) are essential for the assembly and catabolism of Lp(a); however, other proteins associated with the particle may modify its metabolism. Lp(a) specifically carries a cargo of oxidised phospholipids (OxPL) bound to apo(a) which stimulates many proinflammatory pathways in cells of the arterial wall, a key property underlying its pathogenicity and association with cardiovascular disease (CVD). While the liver and kidney are the major tissues implicated in Lp(a) clearance, the pathways for Lp(a) uptake appear to be complex and are still under investigation. Biochemical studies have revealed an exceptional array of receptors that associate with Lp(a) either via its apoB, apo(a), or OxPL components. These receptors fall into five main categories, namely 'classical' lipoprotein receptors, toll-like and scavenger receptors, lectins, and plasminogen receptors. The roles of these receptors have largely been dissected by genetic manipulation in cells or mice, although their relative physiological importance for removal of Lp(a) from the circulation remains unclear. The LPA gene encoding apo(a) has an overwhelming effect on Lp(a) levels which precludes any clear associations between potential Lp(a) receptor genes and Lp(a) levels in population studies. Targeted approaches and the selection of unique Lp(a) phenotypes within populations has nevertheless allowed for some associations to be made. Few of the proposed Lp(a) receptors can specifically be manipulated with current drugs and, as such, it is not currently clear whether any of these receptors could provide relevant targets for therapeutic manipulation of Lp(a) levels. This review summarises the current status of knowledge about receptor-mediated pathways for Lp(a) catabolism.
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Affiliation(s)
- Sally P A McCormick
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
| | - Wolfgang J Schneider
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
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Feng YH, Zheng L, Wei J, Yu MM, Zhang J, Luo GH, Xu N. Increased apolipoprotein M induced by lack of scavenger receptor BI is not activated via HDL-mediated cholesterol uptake in hepatocytes. Lipids Health Dis 2018; 17:200. [PMID: 30144814 PMCID: PMC6109342 DOI: 10.1186/s12944-018-0849-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/13/2018] [Indexed: 11/16/2022] Open
Abstract
Background Scavenger receptor BI (SR-BI) is a classic high-density lipoprotein (HDL) receptor, which mediates selective lipid uptake from HDL cholesterol esters (HDL-C). Apolipoprotein M (ApoM), as a component of HDL particles, could influence preβ-HDL formation and cholesterol efflux. The aim of this study was to determine whether SR-BI deficiency influenced the expression of ApoM. Methods Blood samples and liver tissues were collected from SR-BI gene knockout mice, and serum lipid parameters, including total cholesterol (TC), triglyceride (TG), high and low-density lipoprotein cholesterol (HDL-C and LDL-C) and ApoM were measured. Hepatic ApoM and ApoAI mRNA levels were also determined. In addition, BLT-1, an inhibitor of SR-BI, was added to HepG2 cells cultured with cholesterol and HDL, under serum or serum-free conditions. The mRNA and protein expression levels of ApoM were detected by RT-PCR and western blot. Results We found that increased serum ApoM protein levels corresponded with high hepatic ApoM mRNA levels in both male and female SR-BI−/− mice. Besides, serum TC and HDL-C were also significantly increased. Treatment of HepG2 hepatoma cells with SR-BI specific inhibitor, BLT-1, could up-regulate ApoM expression in serum-containing medium but not in serum-free medium, even in the presence of HDL-C and cholesterol. Conclusions Results suggested that SR-BI deficiency promoted ApoM expression, but the increased ApoM might be independent from HDL-mediated cholesterol uptake in hepatocytes.
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Affiliation(s)
- Yue-Hua Feng
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China
| | - Lu Zheng
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China
| | - Jiang Wei
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China
| | - Miao-Mei Yu
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China
| | - Jun Zhang
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China
| | - Guang-Hua Luo
- Comprehensive Laboratory, the Third Affiliated Hospital, Soochow University, Changzhou, 213003, China.
| | - Ning Xu
- Division of Clinical Chemistry and Pharmacology, Department of Laboratory Medicine, Lunds University, S-221 85, Lund, Sweden.
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13
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Ren K, Jiang T, Zhao GJ. Quercetin induces the selective uptake of HDL-cholesterol via promoting SR-BI expression and the activation of the PPARγ/LXRα pathway. Food Funct 2018; 9:624-635. [PMID: 29292466 DOI: 10.1039/c7fo01107e] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Reverse cholesterol transport (RCT) is the process to deliver cholesterol to the liver for further excretion and involves scavenger receptor class B type I (SR-BI)-mediated selective lipid uptake (SLU) from high-density lipoprotein cholesterol (HDL-C). The up-regulation of hepatic SR-BI expression accelerates HDL-C clearance in circulation and impedes the development of atherosclerosis (AS). In the present study, we explored the modulation of hepatic SR-BI expression and SR-BI-mediated SLU by quercetin, a natural flavonoid compound in the diet with a favorable role in cardiovascular disorders. We found that quercetin significantly increased the expression level of SR-BI in HepG2 cells in a concentration- and time-dependent manner. Besides, quercetin had stimulatory effects on the binding of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil)-labeled HDL to hepatocytes and 125I/3H-CE-HDL association. Treatment with small interfering RNA (siRNA) or SR-BI specific inhibitor, BLT-1, inhibited quercetin-induced Dil-HDL binding and selective HDL-C uptake. Treatment with quercetin increased both proliferator-activated receptor γ (PPARγ) and liver X receptor α (LXRα) levels. Additionally, the quercetin-induced expression of SR-BI, Dil-HDL binding and the selective uptake of HDL-C were significantly attenuated by treatment with PPARγ siRNA, LXRα siRNA, and their antagonists, respectively. In C57BL/6 mice, quercetin administration potently increased SR-BI, PPARγ and LXRα levels and lipid accumulation in the liver. Altogether, our results suggest that quercetin-induced up-regulation of SR-BI and subsequent lipid uptake in hepatocytes might contribute to its beneficial effects on cholesterol homeostasis and atherogenesis.
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Affiliation(s)
- Kun Ren
- Department of Histology and Embryology, Guilin Medical University, Guilin, Guangxi 541004, China.
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Ren K, Zhu X, Zheng Z, Mo ZC, Peng XS, Zeng YZ, Ou HX, Zhang QH, Qi HZ, Zhao GJ, Yi GH. MicroRNA-24 aggravates atherosclerosis by inhibiting selective lipid uptake from HDL cholesterol via the post-transcriptional repression of scavenger receptor class B type I. Atherosclerosis 2018; 270:57-67. [PMID: 29407889 DOI: 10.1016/j.atherosclerosis.2018.01.045] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 01/19/2018] [Accepted: 01/24/2018] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIMS Liver scavenger receptor class B type I (SR-BI) exerts atheroprotective effects through selective lipid uptake (SLU) from high-density lipoprotein cholesterol (HDL-C). Low hepatic SR-BI expression leads to high HDL-C levels in the circulation and an increased risk of atherosclerosis. Furthermore, macrophage SR-BI mediates bidirectional cholesterol flux and may protect against atherogenesis. Previous studies have revealed that miR-24 is closely related to cardiovascular disease (CVD) progression. We aimed to investigate the molecular mechanisms by which miR-24 participates in SR-BI-mediated selective HDL cholesteryl ester (HDL-CE) uptake and further atherogenesis in apoE-/- mice. METHODS Bioinformatic predictions and luciferase reporter assays were utilized to detect the association between miR-24 and the SR-BI 3' untranslated region (3' UTR), and RT-PCR and western blotting were used to evaluate SR-BI mRNA and protein expression, respectively. The effects of miR-24 on Dil-HDL uptake were determined by flow cytometry assay. Double-radiolabeled HDL (125I-TC-/[3H] CEt-HDL) was utilized to measure the effects of miR-24 on HDL and CE binding and SLU in HepG2 and PMA-treated THP-1 cells. In addition, total cholesterol (TC) levels in HepG2 cells were analyzed using enzymatic methods, and macrophage lipid content was evaluated by high-performance liquid chromatography (HPLC) assay. Small interfering RNA (siRNA) and pcDNA3.1(-)-hSR-BI plasmid transfection procedures were utilized to confirm the role of SR-BI in the effects of miR-24 on Dil-HDL uptake, SLU and cholesterol levels in both cell types. Hepatic SR-BI level in apoE-/- mice was measured by western blotting. Liver TC, FC and CE levels and plasma triglycerides (TG), TC and HDL-C levels were evaluated enzymatically using commercial test kits. Atherosclerotic lesion sizes were measured using Oil Red O and hematoxylin-eosin staining. RESULTS miR-24 directly repressed SR-BI expression by targeting its 3'UTR. In addition, miR-24 decreased Dil-HDL uptake and SLU in HepG2 and THP-1 macrophages. In the presence of HDL, miR-24 decreased TC levels in HepG2 cells and TC, free cholesterol (FC) and CE levels in macrophages. Overexpression and down-regulation assays showed that SR-BI mediated the effects of miR-24 on Dil-HDL uptake, SLU and cholesterol levels. Lastly, miR-24 administration decreased hepatic SR-BI expression and promoted atheromatous plaque formation in apoE-/- mice, findings in line with those of our in vitro studies. CONCLUSIONS These findings indicate that miR-24 accelerates atherogenesis by repressing SR-BI-mediated SLU from HDL-C.
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Affiliation(s)
- Kun Ren
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Xiao Zhu
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Zhi Zheng
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Zhong-Cheng Mo
- Department of Histology and Embryology, University of South China, Hengyang, Hunan, 421001, China
| | - Xiao-Shan Peng
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Yong-Zhi Zeng
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Han-Xiao Ou
- Department of Histology and Embryology, University of South China, Hengyang, Hunan, 421001, China
| | - Qing-Hai Zhang
- Clinical Research Institution, The First Affiliated Hospital, University of South China, Hengyang, Hunan, 421001, China
| | - Hui-Zhou Qi
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China
| | - Guo-Jun Zhao
- Department of Histology and Embryology, Guilin Medical University, Guilin, Guangxi, 541004, China
| | - Guang-Hui Yi
- Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang City, 421001, Hunan Province, China.
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Abstract
The scavenger receptor, class B type 1 (SR-B1), is a multiligand membrane receptor protein that functions as a physiologically relevant high-density lipoprotein (HDL) receptor whose primary role is to mediate selective uptake or influx of HDL-derived cholesteryl esters into cells and tissues. SR-B1 also facilitates the efflux of cholesterol from peripheral tissues, including macrophages, back to liver. As a regulator of plasma membrane cholesterol content, SR-B1 promotes the uptake of lipid soluble vitamins as well as viral entry into host cells. These collective functions of SR-B1 ultimately affect programmed cell death, female fertility, platelet function, vasculature inflammation, and diet-induced atherosclerosis and myocardial infarction. SR-B1 has also been identified as a potential marker for cancer diagnosis and prognosis. Finally, the SR-B1-linked selective HDL-cholesteryl ester uptake pathway is now being evaluated as a gateway for the delivery of therapeutic and diagnostic agents. In this review, we focus on the regulation and functional significance of SR-B1 in mediating cholesterol movement into and out of cells.
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Affiliation(s)
- Wen-Jun Shen
- Division of Endocrinology, Gerontology and Metabolism, Stanford University School of Medicine, Stanford, California 94305; .,VA Palo Alto Health Care System, Palo Alto, California 94304
| | - Salman Azhar
- Division of Endocrinology, Gerontology and Metabolism, Stanford University School of Medicine, Stanford, California 94305; .,VA Palo Alto Health Care System, Palo Alto, California 94304
| | - Fredric B Kraemer
- Division of Endocrinology, Gerontology and Metabolism, Stanford University School of Medicine, Stanford, California 94305; .,VA Palo Alto Health Care System, Palo Alto, California 94304
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16
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Abstract
PURPOSE OF REVIEW Elevated high-density lipoprotein cholesterol levels in the blood (HDL-C) represent one of the strongest epidemiological surrogates for protection against coronary heart disease (CHD), but recent human genetic and pharmacological intervention studies have raised controversy about the causality of this relationship. Here, we review recent discoveries from human genome studies using new analytic tools as well as relevant animal studies that have both addressed, and in some cases, fueled this controversy. RECENT FINDINGS Methodologic developments in genotyping and sequencing, such as genome-wide association studies (GWAS), exome sequencing, and exome array genotyping, have been applied to the study of HDL-C and risk of CHD in large, multi-ethnic populations. Some of these efforts focused on population-wide variation in common variants have uncovered new polymorphisms at novel loci associated with HDL-C and, in some cases, CHD risk. Other efforts have discovered loss-of-function variants for the first time in genes previously implicated in HDL metabolism through common variant studies or animal models. These studies have allowed the genetic relationship between these pathways, HDL-C and CHD to be explored in humans for the first time through analysis tools such as Mendelian randomization. We explore these discoveries for selected key HDL-C genes CETP, LCAT, LIPG, SCARB1, and novel loci implicated from GWAS including GALNT2, KLF14, and TTC39B. Recent human genetics findings have identified new nodes regulating HDL metabolism while reshaping our current understanding of known candidate genes to HDL and CHD risk through the study of critical variants across model systems. Despite their effect on HDL-C, variants in many of the reviewed genes were found to lack any association with CHD. These data collectively indicate that HDL-C concentration, which represents a static picture of a very dynamic and heterogeneous metabolic milieu, is unlikely to be itself causally protective against CHD. In this context, human genetics represent an extremely valuable tool to further explore the biological mechanisms regulating HDL metabolism and investigate what role, if any, HDL plays in the pathogenesis of CHD.
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Affiliation(s)
- Cecilia Vitali
- Perelman School of Medicine at the University of Pennsylvania, 11-162 TRC, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Sumeet A Khetarpal
- Perelman School of Medicine at the University of Pennsylvania, 11-162 TRC, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Daniel J Rader
- Perelman School of Medicine at the University of Pennsylvania, 11-162 TRC, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA. .,Departments of Genetics and Medicine, Cardiovascular Institute, and Institute for Translational Medicine and Therapeutics, Perelman School of Medicine at the University of Pennsylvania, 11-125 TRC, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA.
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17
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Abstract
PURPOSE OF REVIEW To outline the roles of SR-B1 and PDZK1 in hepatic selective HDL cholesterol uptake and reverse cholesterol transport and the consequences for atherosclerosis development. RECENT FINDINGS Much of our understanding of the physiological roles of SR-B1 and PDZK1 in HDL metabolism and atherosclerosis comes from studies of genetically manipulated mice. These show SR-B1 and PDZK1 play key roles in HDL metabolism and protection against atherosclerosis. The recent identification of rare loss of function mutations in the human SCARB1 gene verifies that it plays similar roles in HDL metabolism in humans. Other rare mutations in both the human SCARB1 and PDZK1 genes remain to be characterized but may have potentially devastating consequences to SR-B1 function. SUMMARY Identification of carriers of rare mutations in human SCARB1 and PDZK1 that impair the function of their gene products and characterization of the effects of these mutations on HDL cholesterol levels and atherosclerosis will add to our understanding of the importance of HDL function and cholesterol flux, as opposed to HDL-cholesterol levels, per se, for protection against cardiovascular disease.
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Affiliation(s)
- Bernardo L Trigatti
- aDepartment of Biochemistry and Biomedical Sciences, McMaster University bThrombosis and Atherosclerosis Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, Ontario, Canada
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18
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Zhang DM, Jiao RQ, Kong LD. High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions. Nutrients 2017; 9:E335. [PMID: 28353649 PMCID: PMC5409674 DOI: 10.3390/nu9040335] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/15/2017] [Accepted: 03/24/2017] [Indexed: 02/06/2023] Open
Abstract
High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.
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Affiliation(s)
- Dong-Mei Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
| | - Rui-Qing Jiao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
| | - Ling-Dong Kong
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
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Chadwick AC, Jensen DR, Hanson PJ, Lange PT, Proudfoot SC, Peterson FC, Volkman BF, Sahoo D. NMR Structure of the C-Terminal Transmembrane Domain of the HDL Receptor, SR-BI, and a Functionally Relevant Leucine Zipper Motif. Structure 2017; 25:446-457. [PMID: 28162952 DOI: 10.1016/j.str.2017.01.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/23/2016] [Accepted: 01/05/2017] [Indexed: 01/26/2023]
Abstract
The interaction of high-density lipoprotein (HDL) with its receptor, scavenger receptor BI (SR-BI), is critical for lowering plasma cholesterol levels and reducing the risk for cardiovascular disease. The HDL/SR-BI complex facilitates delivery of cholesterol into cells and is likely mediated by receptor dimerization. This work describes the use of nuclear magnetic resonance (NMR) spectroscopy to generate the first high-resolution structure of the C-terminal transmembrane domain of SR-BI. This region of SR-BI harbors a leucine zipper dimerization motif, which when mutated impairs the ability of the receptor to bind HDL and mediate cholesterol delivery. These losses in function correlate with the inability of SR-BI to form dimers. We also identify juxtamembrane regions of the extracellular domain of SR-BI that may interact with the lipid surface to facilitate cholesterol transport functions of the receptor.
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Affiliation(s)
- Alexandra C Chadwick
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Davin R Jensen
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Paul J Hanson
- Division of Endocrinology, Metabolism & Clinical Nutrition, Department of Medicine, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Philip T Lange
- Division of Endocrinology, Metabolism & Clinical Nutrition, Department of Medicine, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Sarah C Proudfoot
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Francis C Peterson
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| | - Daisy Sahoo
- Division of Endocrinology, Metabolism & Clinical Nutrition, Department of Medicine, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA; Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
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20
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Yang X, Sethi A, Yanek LR, Knapper C, Nordestgaard BG, Tybjærg-Hansen A, Becker DM, Mathias RA, Remaley AT, Becker LC. SCARB1 Gene Variants Are Associated With the Phenotype of Combined High High-Density Lipoprotein Cholesterol and High Lipoprotein (a). ACTA ACUST UNITED AC 2016; 9:408-418. [PMID: 27651445 DOI: 10.1161/circgenetics.116.001402] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 08/20/2016] [Indexed: 02/03/2023]
Abstract
BACKGROUND SR-B1 (scavenger receptor class B type 1), encoded by the gene SCARB1, is a lipoprotein receptor that binds both high-density lipoprotein (HDL) and low-density lipoprotein. We reported that SR-B1 is also a receptor for lipoprotein (a) (Lp(a)), mediating cellular uptake of Lp(a) in vitro and promoting clearance of Lp(a) in vivo. Although genetic variants in SCARB1 are associated with variations in HDL level, no SCARB1 variants affecting Lp(a) have been reported. METHODS AND RESULTS In an index subject with high levels of HDL cholesterol and Lp(a), SCARB1 was sequenced and demonstrated a missense mutation resulting in an S129L substitution in exon 3. To follow up, 2 cohorts (GeneSTAR, the family-based Genetic Study of Atherosclerosis Risk [n=543], and CCHS, the population-based Copenhagen City Heart Study [n=5835]) were screened for combined HDL cholesterol and Lp(a) elevations. Subjects with the extreme phenotype (HDL >80 mg/dL and Lp(a) >100 nmol/L in GeneSTAR, n=8, and >100 mg/dL in CCHS, n=9) underwent sequencing of SCARB1 exons; 15 of 18 from the combined population demonstrated genetic variants, including rare or uncommon missense or splice site mutations in 9 and homozygous synonymous variants in 6. Functional studies with 4 of the SCARB1 variants (c.386C>T, c.631-14T>G, c.4G>A, and c.631-53mC>T & c.726+55mCG>CA) showed decreased receptor function in vitro. CONCLUSIONS Human SCARB1 gene variants are associated with a new lipid phenotype, characterized by high levels of both HDL cholesterol and Lp(a). SCARB1 exonic variants often result in diminished function of translated SR-B1 via reduced binding/intracellular transport of Lp(a).
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Affiliation(s)
- Xiaoping Yang
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Amar Sethi
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Lisa R Yanek
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Cathy Knapper
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Børge G Nordestgaard
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Anne Tybjærg-Hansen
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Diane M Becker
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Rasika A Mathias
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Alan T Remaley
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.)
| | - Lewis C Becker
- From the Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD (X.Y., L.R.Y., D.M.B., R.A.M., L.C.B.); Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD (A.S., C.K., A.T.R.); and Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark (B.G.N., A.T.-H.).
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Yang Y, Rosales C, Gillard BK, Gotto AM, Pownall HJ. Acylation of lysine residues in human plasma high density lipoprotein increases stability and plasma clearance in vivo. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1787-1795. [PMID: 27594697 DOI: 10.1016/j.bbalip.2016.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 10/21/2022]
Abstract
Although human plasma high density lipoproteins (HDL) concentrations negatively correlate with atherosclerotic cardiovascular disease, underlying mechanisms are unknown. Thus, there is continued interest in HDL structure and functionality. Numerous plasma factors disrupt HDL structure while inducing the release of lipid free apolipoprotein (apo) AI. Given that HDL is an unstable particle residing in a kinetic trap, we tested whether HDL could be stabilized by acylation with acetyl and hexanoyl anhydrides, giving AcHDL and HexHDL respectively. Lysine analysis with fluorescamine showed that AcHDL and HexHDL respectively contained 11 acetyl and 19 hexanoyl groups. Tests with biological and physicochemical perturbants showed that HexHDL was more stable than HDL to perturbant-induced lipid free apo AI formation. Like the reaction of streptococcal serum opacity factor against HDL, the interaction of HDL with its receptor, scavenger receptor class B member 1 (SR-B1), removes CE from HDL. Thus, we tested and validated the hypothesis that selective uptake of HexHDL-[3H]CE by Chinese Hamster Ovary cells expressing SR-B1 is less than that of HDL-[3H]CE; thus, selective SR-B1 uptake of HDL-CE depends on HDL instability. However, in mice, plasma clearance, hepatic uptake and sterol secretion into bile were faster from HexHDL-[3H]CE than from HDL-[3H]CE. Collectively, our data show that acylation increases HDL stability and that the reaction of plasma factors with HDL and SR-B1-mediated uptake are reduced by increased HDL stability. In vivo data suggest that HexHDL promotes charge-dependent reverse cholesterol transport, by a mechanism that increases hepatic sterol uptake via non SR-B1 receptors, thereby increasing bile acid output.
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Affiliation(s)
- Yaliu Yang
- Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, PR China.
| | - Corina Rosales
- Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; Weill Cornell Medicine, 1305 York Avenue, New York, NY 10065, USA.
| | - Baiba K Gillard
- Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; Weill Cornell Medicine, 1305 York Avenue, New York, NY 10065, USA.
| | - Antonio M Gotto
- Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; Weill Cornell Medicine, 1305 York Avenue, New York, NY 10065, USA.
| | - Henry J Pownall
- Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; Weill Cornell Medicine, 1305 York Avenue, New York, NY 10065, USA.
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22
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Yang F, Du Y, Zhang J, Jiang Z, Wang L, Hong B. Low-density lipoprotein upregulate SR-BI through Sp1 Ser702 phosphorylation in hepatic cells. Biochim Biophys Acta 2016; 1861:1066-1075. [PMID: 27320013 DOI: 10.1016/j.bbalip.2016.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 05/04/2016] [Accepted: 06/10/2016] [Indexed: 01/25/2023]
Abstract
Scavenger receptor class B type I (SR-BI) is one of the key proteins in the process of reverse cholesterol transport (RCT), and its major function is to uptake high density lipoprotein (HDL) cholesterol from plasma into liver cells. The regulation of SR-BI expression is important for controlling serum lipid content and reducing the risks of cardiovascular diseases. Here we found that SR-BI expression was significantly increased by LDL in vivo and in vitro, and the transcription factor specific protein 1 (Sp1) plays a critical role in this process. Results from co-immunoprecipitation experiments indicate that the activation of SR-BI was associated with Sp1-recruited protein complexes in the promoter region of SR-BI, where histone acetyltransferase p300 was recruited and histone deacetylase HDAC1 was dismissed. As a result, histone acetylation increased, leading to activation of SR-BI transcription. With further investigation, we found that LDL phosphorylated Sp1 through ERK1/2 pathway, which affected Sp1 protein complexes formation in SR-BI promoter. Using mass spectrometry and site directed mutagenesis, a new Sp1 phosphorylation site Ser702 was defined to be associated with Sp1-HDAC1 interaction and may be important in SR-BI activation, shedding light on the knowledge of delicate mechanism of hepatic HDL receptor SR-BI gene modulation by LDL.
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Affiliation(s)
- Fan Yang
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China
| | - Yu Du
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China
| | - Jin Zhang
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China
| | - Zhibo Jiang
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China
| | - Li Wang
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China.
| | - Bin Hong
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Tiantan Xili, Beijing 100050, China.
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23
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Zanoni P, Khetarpal SA, Larach DB, Hancock-Cerutti WF, Millar JS, Cuchel M, DerOhannessian S, Kontush A, Surendran P, Saleheen D, Trompet S, Jukema JW, De Craen A, Deloukas P, Sattar N, Ford I, Packard C, Majumder AAS, Alam DS, Di Angelantonio E, Abecasis G, Chowdhury R, Erdmann J, Nordestgaard BG, Nielsen SF, Tybjærg-Hansen A, Schmidt RF, Kuulasmaa K, Liu DJ, Perola M, Blankenberg S, Salomaa V, Männistö S, Amouyel P, Arveiler D, Ferrieres J, Müller-Nurasyid M, Ferrario M, Kee F, Willer CJ, Samani N, Schunkert H, Butterworth AS, Howson JMM, Peloso GM, Stitziel NO, Danesh J, Kathiresan S, Rader DJ. Rare variant in scavenger receptor BI raises HDL cholesterol and increases risk of coronary heart disease. Science 2016; 351:1166-71. [PMID: 26965621 DOI: 10.1126/science.aad3517] [Citation(s) in RCA: 393] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Scavenger receptor BI (SR-BI) is the major receptor for high-density lipoprotein (HDL) cholesterol (HDL-C). In humans, high amounts of HDL-C in plasma are associated with a lower risk of coronary heart disease (CHD). Mice that have depleted Scarb1 (SR-BI knockout mice) have markedly elevated HDL-C levels but, paradoxically, increased atherosclerosis. The impact of SR-BI on HDL metabolism and CHD risk in humans remains unclear. Through targeted sequencing of coding regions of lipid-modifying genes in 328 individuals with extremely high plasma HDL-C levels, we identified a homozygote for a loss-of-function variant, in which leucine replaces proline 376 (P376L), in SCARB1, the gene encoding SR-BI. The P376L variant impairs posttranslational processing of SR-BI and abrogates selective HDL cholesterol uptake in transfected cells, in hepatocyte-like cells derived from induced pluripotent stem cells from the homozygous subject, and in mice. Large population-based studies revealed that subjects who are heterozygous carriers of the P376L variant have significantly increased levels of plasma HDL-C. P376L carriers have a profound HDL-related phenotype and an increased risk of CHD (odds ratio = 1.79, which is statistically significant).
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Affiliation(s)
- Paolo Zanoni
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sumeet A Khetarpal
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daniel B Larach
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - William F Hancock-Cerutti
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. INSERM UMR 1166 ICAN, Université Pierre et Marie Curie Paris 6, Hôpital de la Pitié, Paris, France
| | - John S Millar
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marina Cuchel
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stephanie DerOhannessian
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anatol Kontush
- INSERM UMR 1166 ICAN, Université Pierre et Marie Curie Paris 6, Hôpital de la Pitié, Paris, France
| | - Praveen Surendran
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Danish Saleheen
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK. Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. Centre for Non-Communicable Diseases, Karachi, Pakistan
| | - Stella Trompet
- Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, Netherlands. Department of Cardiology, Leiden University Medical Center, Leiden, Netherlands
| | - J Wouter Jukema
- Department of Cardiology, Leiden University Medical Center, Leiden, Netherlands. The Interuniversity Cardiology Institute of the Netherlands, Utrecht, Netherlands
| | - Anton De Craen
- Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, Netherlands
| | - Panos Deloukas
- Wellcome Trust Sanger Institute, Genome Campus, Hinxton, UK
| | - Naveed Sattar
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation, Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
| | - Ian Ford
- Robertson Center for Biostatistics, University of Glasgow, Glasgow, UK
| | - Chris Packard
- Glasgow Clinical Research Facility, Western Infirmary, Glasgow, UK
| | | | - Dewan S Alam
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh
| | - Emanuele Di Angelantonio
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Goncalo Abecasis
- Center for Statistical Genetics, Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA
| | - Rajiv Chowdhury
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Jeanette Erdmann
- Institute for Integrative and Experimental Genomics, University of Lübeck, Lübeck 23562, Germany
| | - Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, Herlev, Denmark
| | - Sune F Nielsen
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, Herlev, Denmark
| | - Anne Tybjærg-Hansen
- Copenhagen University Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Ruth Frikke Schmidt
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospitals, Copenhagen, Denmark
| | - Kari Kuulasmaa
- Department of Health, National Institute for Health and Welfare, Helsinki, Finland
| | - Dajiang J Liu
- Department of Public Health Sciences, College of Medicine, Pennsylvania State University, Hershey, PA 17033, USA
| | - Markus Perola
- Department of Health, National Institute for Health and Welfare, Helsinki, Finland. Institute of Molecular Medicine FIMM, University of Helsinki, Helsinki, Finland
| | - Stefan Blankenberg
- Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany. University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Veikko Salomaa
- Department of Health, National Institute for Health and Welfare, Helsinki, Finland
| | - Satu Männistö
- Department of Health, National Institute for Health and Welfare, Helsinki, Finland
| | - Philippe Amouyel
- Department of Epidemiology and Public Health, Institut Pasteur de Lille, Lille, France
| | - Dominique Arveiler
- Department of Epidemiology and Public Health, University of Strasbourg, Strasbourg, France
| | - Jean Ferrieres
- Department of Epidemiology, Toulouse University-CHU Toulouse, Toulouse, France
| | - Martina Müller-Nurasyid
- Institute of Genetic Epidemiology, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany. Department of Medicine I, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Marco Ferrario
- Research Centre in Epidemiology and Preventive Medicine, Department of Clinical and Experimental Medicine, University of Insubria, Varese, Italy
| | - Frank Kee
- UKCRC Centre of Excellence for Public Health, Queens University, Belfast, Northern Ireland
| | - Cristen J Willer
- Department of Computational Medicine and Bioinformatics, Department of Human Genetics, and Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nilesh Samani
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK. National Institute for Health Research (NIHR) Leicester Cardiovascular Biomedical Research Unit, Glenfield Hotel, Leicester, UK
| | - Heribert Schunkert
- Deutsches Herzzentrum München, Technische Universität München, Munich, Germany
| | - Adam S Butterworth
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Joanna M M Howson
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Gina M Peloso
- Broad Institute and Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Nathan O Stitziel
- Department of Medicine, Division of Cardiology, Department of Genetics, and the McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - John Danesh
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK. Wellcome Trust Sanger Institute, Genome Campus, Hinxton, UK
| | - Sekar Kathiresan
- Broad Institute and Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Daniel J Rader
- Departments of Genetics and Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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24
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Hoekstra M, Van Eck M. HDL is redundant for adrenal steroidogenesis in LDLR knockout mice with a human-like lipoprotein profile. J Lipid Res 2016; 57:631-7. [PMID: 26891738 DOI: 10.1194/jlr.m066019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Indexed: 11/20/2022] Open
Abstract
The contribution of HDL to adrenal steroidogenesis appears to be different between mice and humans. In the current study, we tested the hypothesis that a difference in lipoprotein profile may be the underlying cause. Hereto, we determined the impact of HDL deficiency on the adrenal glucocorticoid output in genetically modified mice with a human-like lipoprotein profile. Genetic deletion of APOA1 in LDL receptor (LDLR) knockout mice was associated with HDL deficiency and a parallel increase in the level of cholesterol associated with nonHDL fractions. Despite a compensatory increase in the adrenal relative mRNA expression levels of the cholesterol synthesis gene, HMG-CoA reductase, adrenals from APOA1/LDLR double knockout mice were severely depleted of neutral lipids, as compared with those of control LDLR knockout mice. However, basal corticosterone levels and the adrenal glucocorticoid response to stress were not different between the two types of mice. In conclusion, we have shown that HDL is not critical for proper adrenal glucocorticoid function when mice are provided with a human-like lipoprotein profile. Our findings provide the first experimental evidence that APOB-containing lipoproteins may facilitate adrenal steroidogenesis, in an LDLR-independent manner, in vivo in mice.
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Affiliation(s)
- Menno Hoekstra
- Division of Biopharmaceutics, Cluster BioTherapeutics, Leiden Academic Centre for Drug Research, Gorlaeus Laboratories, 2333CC Leiden, The Netherlands
| | - Miranda Van Eck
- Division of Biopharmaceutics, Cluster BioTherapeutics, Leiden Academic Centre for Drug Research, Gorlaeus Laboratories, 2333CC Leiden, The Netherlands
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Niemsiri V, Wang X, Pirim D, Radwan ZH, Bunker CH, Barmada MM, Kamboh MI, Demirci FY. Genetic contribution of SCARB1 variants to lipid traits in African Blacks: a candidate gene association study. BMC Med Genet 2015; 16:106. [PMID: 26563154 PMCID: PMC4643515 DOI: 10.1186/s12881-015-0250-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 10/30/2015] [Indexed: 12/03/2022]
Abstract
Background High-density lipoprotein cholesterol (HDL-C) exerts many anti-atherogenic properties including its role in reverse cholesterol transport (RCT). Scavenger receptor class B member 1 (SCARB1) plays a key role in RCT by selective uptake of HDL cholesteryl esters. We aimed to explore the genetic contribution of SCARB1 to affecting lipid levels in African Blacks from Nigeria. Methods We resequenced 13 exons and exon-intron boundaries of SCARB1 in 95 individuals with extreme HDL-C levels using Sanger method. Then, we genotyped 147 selected variants (78 sequence variants, 69 HapMap tagSNPs, and 2 previously reported relevant variants) in the entire sample of 788 African Blacks using either the iPLEX Gold or TaqMan methods. A total of 137 successfully genotyped variants were further evaluated for association with major lipid traits. Results The initial gene-based analysis demonstrated evidence of association with HDL-C and apolipoprotein A-I (ApoA-I). The follow-up single-site analysis revealed nominal evidence of novel associations of nine common variants with HDL-C and/or ApoA-I (P < 0.05). The strongest association was between rs11057851 and HDL-C (P = 0.0043), which remained significant after controlling for multiple testing using false discovery rate. Rare variant association testing revealed a group of 23 rare variants (frequencies ≤1 %) associated with HDL-C (P = 0.0478). Haplotype analysis identified four SCARB1 regions associated with HDL-C (global P < 0.05). Conclusions To our knowledge, this is the first report of a comprehensive association study of SCARB1 variations with lipid traits in an African Black population. Our results showed the consistent association of SCARB1 variants with HDL-C across various association analyses, supporting the role of SCARB1 in lipoprotein-lipid regulatory mechanism. Electronic supplementary material The online version of this article (doi:10.1186/s12881-015-0250-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Vipavee Niemsiri
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - Xingbin Wang
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - Dilek Pirim
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - Zaheda H Radwan
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - Clareann H Bunker
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - M Michael Barmada
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - M Ilyas Kamboh
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
| | - F Yesim Demirci
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, Pittsburgh, PA, 15261, USA.
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26
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Karavia EA, Hatziri A, Kalogeropoulou C, Papachristou NI, Xepapadaki E, Constantinou C, Natsos A, Petropoulou PI, Sasson S, Papachristou DJ, Kypreos KE. Deficiency in apolipoprotein A-I ablates the pharmacological effects of metformin on plasma glucose homeostasis and hepatic lipid deposition. Eur J Pharmacol 2015; 766:76-85. [DOI: 10.1016/j.ejphar.2015.09.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 09/23/2015] [Accepted: 09/24/2015] [Indexed: 12/25/2022]
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27
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Vaisman BL, Vishnyakova TG, Freeman LA, Amar MJ, Demosky SJ, Liu C, Stonik JA, Sampson ML, Pryor M, Bocharov AV, Eggerman TL, Patterson AP, Remaley AT. Endothelial Expression of Scavenger Receptor Class B, Type I Protects against Development of Atherosclerosis in Mice. Biomed Res Int 2015; 2015:607120. [PMID: 26504816 DOI: 10.1155/2015/607120] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 07/10/2015] [Accepted: 07/24/2015] [Indexed: 11/23/2022]
Abstract
The role of scavenger receptor class B, type I (SR-BI) in endothelial cells (EC) was examined in several novel transgenic mouse models expressing SR-BI in endothelium of mice with normal C57Bl6/N, apoE-KO, or Scarb1-KO backgrounds. Mice were also created expressing SR-BI exclusively in endothelium and liver. Endothelial expression of the Tie2-Scarb1 transgene had no significant effect on plasma lipoprotein levels in mice on a normal chow diet but on an atherogenic diet, significantly decreased plasma cholesterol levels, increased plasma HDL cholesterol (HDL-C) levels, and protected mice against atherosclerosis. In 8-month-old apoE-KO mice fed a normal chow diet, the Tie2-Scarb1 transgene decreased aortic lesions by 24%. Mice expressing SR-BI only in EC and liver had a 1.5 ± 0.1-fold increase in plasma cholesterol compared to mice synthesizing SR-BI only in liver. This elevation was due mostly to increased HDL-C. In EC culture studies, SR-BI was found to be present in both basolateral and apical membranes but greater cellular uptake of cholesterol from HDL was found in the basolateral compartment. In summary, enhanced expression of SR-BI in EC resulted in a less atherogenic lipoprotein profile and decreased atherosclerosis, suggesting a possible role for endothelial SR-BI in the flux of cholesterol across EC.
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28
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Karavia EA, Papachristou NI, Sakellaropoulos GC, Xepapadaki E, Papamichail E, Petropoulou PI, Papakosta EP, Constantinou C, Habeos I, Papachristou DJ, Kypreos KE. Scavenger Receptor Class B Type I Regulates Plasma Apolipoprotein E Levels and Dietary Lipid Deposition to the Liver. Biochemistry 2015; 54:5605-16. [DOI: 10.1021/acs.biochem.5b00700] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Eleni A. Karavia
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Nikolaos I. Papachristou
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - George C. Sakellaropoulos
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Eva Xepapadaki
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Eleni Papamichail
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Peristera-Ioanna Petropoulou
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Eugenia P. Papakosta
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Caterina Constantinou
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Ioannis Habeos
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Dionysios J. Papachristou
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
| | - Kyriakos E. Kypreos
- Pharmacology
Department, ‡Anatomy Histology and Embryology Department, §Medical Physics Department, and ∥Endocrinology
Department, University of Patras Medical School, Rio Achaias, TK 26500, Greece
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Lino M, Farr S, Baker C, Fuller M, Trigatti B, Adeli K. Intestinal scavenger receptor class B type I as a novel regulator of chylomicron production in healthy and diet-induced obese states. Am J Physiol Gastrointest Liver Physiol 2015; 309:G350-9. [PMID: 26138463 DOI: 10.1152/ajpgi.00086.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 06/25/2015] [Indexed: 01/31/2023]
Abstract
The small intestine contributes to diabetic dyslipidemia through the overproduction of apolipoprotein B48 (apoB48)-containing chylomicron particles. An important regulator of chylomicron generation is dietary lipid absorption, underlining the potential involvement of intestinal lipid transporters for developing dyslipidemia. Intestinal expression of scavenger receptor class B type I (SR-BI) has been found to be upregulated in animal models of insulin resistance. Here we characterized the potential importance of SR-BI in contributing to chylomicron production and postprandial hypertriglyceridemia in vivo. Postprandial triglyceride (TG)-rich lipoprotein (TRL) production was characterized in hamsters treated with the SR-BI inhibitor to block lipid transport-1 (BLT-1) under healthy conditions or conditions of diet-induced obesity and dyslipidemia. BLT-1 (1 mg/kg) or vehicle was administered acutely in chow-fed hamsters or gavaged twice daily over 10 days during high-fructose, high-fat, high-cholesterol (FFC) feeding. Effects of acute SR-BI inhibition by BLT-1 were confirmed in healthy fat-loaded rats. Finally, plasma lipid levels were compared between SR-BI(-/-) mice and their wild-type counterparts fed either chow or a 12-wk high-fat diet. Acute BLT-1 treatment reduced postprandial plasma and TRL TG levels in healthy hamsters and rats. Chronic BLT-1 treatment of FFC-fed hamsters blunted diet-induced weight gain and fasting hypertriglyceridemia, and lowered postprandial TRL-TG, -cholesterol, and -apoB48 levels. Finally, SR-BI(-/-) mice displayed lower plasma and TRL TG levels relative to wild type, and diet-induced weight gain and postprandial hypertriglyceridemia were hindered in SR-BI(-/-) mice. We conclude that intestinal SR-BI is a critical regulator of postprandial lipoprotein production, emphasizing its potential as a target for preventing diabetic dyslipidemia.
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Affiliation(s)
- Marsel Lino
- Department of Molecular Structure and Function, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; and
| | - Sarah Farr
- Department of Molecular Structure and Function, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; and
| | - Chris Baker
- Department of Molecular Structure and Function, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Mark Fuller
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Bernardo Trigatti
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Khosrow Adeli
- Department of Molecular Structure and Function, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; and
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30
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Zhao Y, Hoekstra M, Korporaal SJA, Van Berkel TJC, Van Eck M. HDL Receptor Scavenger Receptor BI. Atherosclerosis 2015. [DOI: 10.1002/9781118828533.ch25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Lichtenstein L, Serhan N, Espinosa-Delgado S, Fabre A, Annema W, Tietge UJF, Robaye B, Boeynaems JM, Laffargue M, Perret B, Martinez LO. Increased atherosclerosis in P2Y13/apolipoprotein E double-knockout mice: contribution of P2Y13 to reverse cholesterol transport. Cardiovasc Res 2015; 106:314-23. [PMID: 25770145 DOI: 10.1093/cvr/cvv109] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/07/2015] [Indexed: 11/14/2022] Open
Abstract
AIMS High-density lipoproteins (HDLs) protect against atherosclerosis mainly due to their function in hepatobiliary reverse cholesterol transport (RCT). This is a process whereby excess cholesterol from peripheral tissues is transported by HDL particles to the liver for further metabolism and biliary excretion. Hepatic uptake of HDL holoparticles involves the P2Y13 receptor, independently of the selective cholesteryl ester uptake mediated by scavenger receptor class B, type I (SR-BI). Accordingly, P2Y13-deficient mice (P2Y13 (-/-)) have impaired RCT. This study assessed whether P2Y13 deficiency would affect atherosclerotic development. METHODS AND RESULTS P2Y13 (-/-) mice were crossbred with atherosclerosis-prone apoE(-/-) mice. When 15 weeks old, P2Y13 (-/-)/apoE(-/-) mice had more aortic sinus lesions than apoE(-/-) mice. Bone marrow transplantation showed that the absence of the P2Y13 receptor in blood cells did not lead to significantly greater atherosclerotic plaque size formation compared with control apoE(-/-) reconstituted animals. Conversely, the absence of the P2Y13 receptor, except in blood cells, resulted in lesion sizes similar to that in P2Y13 (-/-)/apoE(-/-) reconstituted mice, pointing to a role for non-haematopoietic-derived P2Y13. Unexpectedly, P2Y13 (-/-)/apoE(-/-) mice displayed a lower HDL-cholesterol level than apoE(-/-) mice, which might be due to greater SR-BI expression in the liver. However, P2Y13 deficiency in apoE(-/-) mice was translated into reduced biliary and faecal sterol excretion and impaired RCT from macrophage to faeces, suggesting that an alteration in hepatobiliary RCT could be solely responsible for the greater atherosclerosis observed. CONCLUSION The P2Y13 receptor protects against atherosclerosis, primarily through its role in hepatobiliary RCT.
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Affiliation(s)
- Laeticia Lichtenstein
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France
| | - Nizar Serhan
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France
| | - Sara Espinosa-Delgado
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France
| | - Aurélie Fabre
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France
| | - Wijtske Annema
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Uwe J F Tietge
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Bernard Robaye
- Institute of Interdisciplinary Research, IRIBHM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Jean-Marie Boeynaems
- Institute of Interdisciplinary Research, IRIBHM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Muriel Laffargue
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France
| | - Bertrand Perret
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France CHU de Toulouse, Hôpital Purpan, Toulouse, France
| | - Laurent O Martinez
- INSERM, UMR 1048, Institut de Maladies Métaboliques et Cardiovasculaires, Toulouse, France Université de Toulouse III, UMR 1048, Toulouse, France CHU de Toulouse, Hôpital Purpan, Toulouse, France INSERM U1048, Bât. L3, Hôpital Rangueil, BP 84225, 31432 Toulouse cedex 04, France
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Andriani Y, Tengku-Muhammad TS, Mohamad H, Saidin J, Syamsumir DF, Chew GS, Abdul Wahid ME. Phaleria macrocarpa Boerl. (Thymelaeaceae) leaves increase SR-BI expression and reduce cholesterol levels in rats fed a high cholesterol diet. Molecules 2015; 20:4410-29. [PMID: 25759957 PMCID: PMC6272643 DOI: 10.3390/molecules20034410] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/23/2014] [Accepted: 01/13/2015] [Indexed: 11/16/2022] Open
Abstract
In vitro and in vivo studies of the activity of Phaleria macrocarpa Boerl (Thymelaeaceae) leaves against the therapeutic target for hypercholesterolemia were done using the HDL receptor (SR-BI) and hypercholesterolemia-induced Sprague Dawley rats. The in vitro study showed that the active fraction (CF6) obtained from the ethyl acetate extract (EMD) and its component 2',6',4-trihydroxy-4'-methoxybenzophenone increased the SR-BI expression by 95% and 60%, respectively. The in vivo study has proven the effect of EMD at 0.5 g/kgbw dosage in reducing the total cholesterol level by 224.9% and increasing the HDL cholesterol level by 157% compared to the cholesterol group. In the toxicity study, serum glutamate oxalate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) activity were observed to be at normal levels. The liver histology also proved no toxicity and abnormalities in any of the treatment groups, so it can be categorized as non-toxic to the rat liver. The findings taken together show that P. macrocarpa leaves are safe and suitable as an alternative control and prevention treatment for hypercholesterolemia in Sprague Dawley rats.
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Affiliation(s)
- Yosie Andriani
- Institute of Marine Biotechnology, University of Malaysia Terengganu, Kuala Terengganu 21030, Terengganu, Malaysia.
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Bengkulu (UNIB), Bengkulu 38371, Indonesia.
| | | | - Habsah Mohamad
- Institute of Marine Biotechnology, University of Malaysia Terengganu, Kuala Terengganu 21030, Terengganu, Malaysia.
| | - Jasnizat Saidin
- Institute of Marine Biotechnology, University of Malaysia Terengganu, Kuala Terengganu 21030, Terengganu, Malaysia.
| | - Desy Fitrya Syamsumir
- Institute of Marine Biotechnology, University of Malaysia Terengganu, Kuala Terengganu 21030, Terengganu, Malaysia.
| | - Guat-Siew Chew
- Biomedical Science, School of Health Sciences, Federation University, Ballarat 3350, Australia.
| | - Mohd Effendy Abdul Wahid
- Institute of Marine Biotechnology, University of Malaysia Terengganu, Kuala Terengganu 21030, Terengganu, Malaysia.
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Hebel T, Eisinger K, Neumeier M, Rein-Fischboeck L, Pohl R, Meier EM, Boettcher A, Froehner SC, Adams ME, Liebisch G, Krautbauer S, Buechler C. Lipid abnormalities in alpha/beta2-syntrophin null mice are independent from ABCA1. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:527-36. [PMID: 25625330 DOI: 10.1016/j.bbalip.2015.01.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 01/12/2015] [Accepted: 01/19/2015] [Indexed: 01/27/2023]
Abstract
The syntrophins alpha (SNTA) and beta 2 (SNTB2) are molecular adaptor proteins shown to stabilize ABCA1, an essential regulator of HDL cholesterol. Furthermore, SNTB2 is involved in glucose stimulated insulin release. Hyperglycemia and dyslipidemia are characteristic features of the metabolic syndrome, a serious public health problem with rising prevalence. Therefore, it is important to understand the role of the syntrophins herein. Mice deficient for both syntrophins (SNTA/B2-/-) have normal insulin and glucose tolerance, hepatic ABCA1 protein and cholesterol. When challenged with a HFD, wild type and SNTA/B2-/- mice have similar weight gain, adiposity, serum and liver triglycerides. Hepatic ABCA1, serum insulin and insulin sensitivity are normal while glucose tolerance is impaired. Liver cholesterol is reduced, and expression of SREBP2 and HMG-CoA-R is increased in the knockout mice. Scavenger receptor-BI (SR-BI) protein is strongly diminished in the liver of SNTA/B2-/- mice while SR-BI binding protein NHERF1 is not changed and PDZK1 is even induced. Knock-down of SNTA, SNTB2 or both has no effect on hepatocyte SR-BI and PDZK1 proteins. Further, SR-BI levels are not reduced in brown adipose tissue of SNTA/B2-/- mice excluding that syntrophins directly stabilize SR-BI. SR-BI stability is regulated by MAPK and phosphorylated ERK2 is induced in the liver of the knock-out mice. Blockage of ERK activity upregulates hepatocyte SR-BI showing that increased MAPK activity contributes to low SR-BI. Sphingomyelin which is well described to regulate cholesterol metabolism is reduced in the liver and serum of the knock-out mice while the size of serum lipoproteins is not affected. Current data exclude a major function of these syntrophins in ABCA1 activity and insulin release but suggest a role in regulating glucose uptake, ERK and SR-BI levels, and sphingomyelin metabolism in obesity.
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Affiliation(s)
- Tobias Hebel
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Kristina Eisinger
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Markus Neumeier
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Lisa Rein-Fischboeck
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Rebekka Pohl
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Elisabeth M Meier
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Alfred Boettcher
- Institute for Clinical Chemistry and Laboratory Medicine, Regensburg University Hospital, Regensburg, Germany
| | - Stanley C Froehner
- Department of Physiology and Biophysics, University of Washington, WA, USA
| | - Marvin E Adams
- Department of Physiology and Biophysics, University of Washington, WA, USA
| | - Gerhard Liebisch
- Institute for Clinical Chemistry and Laboratory Medicine, Regensburg University Hospital, Regensburg, Germany
| | - Sabrina Krautbauer
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany
| | - Christa Buechler
- Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany.
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Li C, Tu Y, Liu TR, Guo ZG, Xie D, Zhong JK, Fan YZ, Lai WY. Rosiglitazone attenuates atherosclerosis and increases high-density lipoprotein function in atherosclerotic rabbits. Int J Mol Med 2015; 35:715-23. [PMID: 25604880 PMCID: PMC4314417 DOI: 10.3892/ijmm.2015.2072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 01/09/2015] [Indexed: 11/30/2022] Open
Abstract
Rosiglitazone has been found to have anti-atherogenic effects and to increase serum high-density lipoprotein (HDL) cholesterol (HDL-C) levels. However, in vivo studies investigating the regulation of adenosine triphosphate-binding cassette transporter A1 (ABCA1) and scavenger receptor class B type I (SR-BI) by rosiglitazone are limited. Moreover, the effects of rosiglitazone on the function and levels of HDL are unclear. In the present study, we investigated the effects of rosiglitazone on HDL function and its mechanisms of action in atherosclerotic rabbits. Our results revealed that rosiglitazone induced a significant increase in serum HDL-C levels, paraoxonase 1 (PON1) activity, [3H]cholesterol efflux rates, and the expression of ABCA1 and SR-BI in hepatocytes and peritoneal macrophages. The expression of ABCA1 was also increased in aortic lesions. Rosiglitazone markedly reduced serum myeloperoxidase (MPO) activity, aortic intima-media thickness (IMT) and the percentage of plaque area in the aorta. It can thus be concluded that in atherosclerotic rabbits, rosigitazone increases the levels of HDL-C and hinders atherosclerosis. Thus, it improves HDL quality and function, as well as the HDL-induced cholesterol efflux, exerting anti-inflammatory and antioxidant effects.
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Affiliation(s)
- Chen Li
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Yan Tu
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Ting-Rong Liu
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Zhi-Gang Guo
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Di Xie
- Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Jian-Kai Zhong
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Yong-Zhen Fan
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Wen-Yan Lai
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
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Abstract
In this chapter, we review how HDL is generated, remodeled, and catabolized in plasma. We describe key features of the proteins that participate in these processes, emphasizing how mutations in apolipoprotein A-I (apoA-I) and the other proteins affect HDL metabolism. The biogenesis of HDL initially requires functional interaction of apoA-I with the ATP-binding cassette transporter A1 (ABCA1) and subsequently interactions of the lipidated apoA-I forms with lecithin/cholesterol acyltransferase (LCAT). Mutations in these proteins either prevent or impair the formation and possibly the functionality of HDL. Remodeling and catabolism of HDL is the result of interactions of HDL with cell receptors and other membrane and plasma proteins including hepatic lipase (HL), endothelial lipase (EL), phospholipid transfer protein (PLTP), cholesteryl ester transfer protein (CETP), apolipoprotein M (apoM), scavenger receptor class B type I (SR-BI), ATP-binding cassette transporter G1 (ABCG1), the F1 subunit of ATPase (Ecto F1-ATPase), and the cubulin/megalin receptor. Similarly to apoA-I, apolipoprotein E and apolipoprotein A-IV were shown to form discrete HDL particles containing these apolipoproteins which may have important but still unexplored functions. Furthermore, several plasma proteins were found associated with HDL and may modulate its biological functions. The effect of these proteins on the functionality of HDL is the topic of ongoing research.
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Affiliation(s)
- Vassilis I Zannis
- Molecular Genetics, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, 02118, USA,
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Ali K, Abo-Ali EM, Kabir MD, Riggins B, Nguy S, Li L, Srivastava U, Thinn SMM. A Western-fed diet increases plasma HDL and LDL-cholesterol levels in apoD-/- mice. PLoS One 2014; 9:e115744. [PMID: 25548917 PMCID: PMC4280175 DOI: 10.1371/journal.pone.0115744] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 11/27/2014] [Indexed: 01/26/2023] Open
Abstract
Objective Plasma apolipoprotein (apo)D, a ubiquitously expressed protein that binds small hydrophobic ligands, is found mainly on HDL particles. According to studies of human genetics and lipid disorders, plasma apoD levels positively correlate with HDL-cholesterol and apoAI levels. Thus, we tested the hypothesis that apoD was a regulator of HDL metabolism. Methods & Results We compared the plasma lipid and lipoprotein profiles of wild-type (WT) C57BL/6 mice with apoD−/− mice on a C57BL/6 background after receiving a high fat-high cholesterol diet for 12 weeks. ApoD−/− mice had higher HDL-cholesterol levels (61±13-apoD−/− vs. 52±10-WT-males; 37±11-apoD−/− vs. 22±2 WT-female) than WT mice with sex-specific changes in total plasma levels of cholesterol and other lipids. Compared to WT, the HDL of apoD−/− mice showed an increase in large, lipid-rich HDL particles and according to size various quantities and sizes of LDL particles. Plasma levels of lecithin:cholesterol acyltransferase in the control and apoD−/− mice were not different, however, plasma phospholipid transfer protein activity was modestly elevated (+10%) only in male apoD−/− mice. An invivo HDL metabolism experiment with isolated Western-fed apoD−/− HDL particles showed that female apoD−/− mice had a 36% decrease in the fractional catabolic rate of HDL cholesteryl ester. Hepatic SR-BI and LDLR protein levels were significantly decreased; accordingly, LDL-cholesterol and apoB levels were increased in female mice. Conclusion In the context of a high fat-high cholesterol diet, apoD deficiency in female mice is associated with increases in both plasma HDL and LDL-cholesterol levels, reflecting changes in expression of SR-BI and LDL receptors, which may impact diet-induced atherosclerosis.
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Affiliation(s)
- Kamilah Ali
- The City College of New York, Biology Department, New York, New York, United States of America
- Graduate Center at CUNY, New York, New York, United States of America
- * E-mail:
| | - Ehab M. Abo-Ali
- The City College of New York, Biology Department, New York, New York, United States of America
- Graduate Center at CUNY, New York, New York, United States of America
| | - M. D. Kabir
- The City College of New York, Biology Department, New York, New York, United States of America
| | - Bethany Riggins
- The City College of New York, Biology Department, New York, New York, United States of America
| | - Susanna Nguy
- The City College of New York, Biology Department, New York, New York, United States of America
| | - Lisa Li
- The City College of New York, Biology Department, New York, New York, United States of America
| | - Ujala Srivastava
- The City College of New York, Biology Department, New York, New York, United States of America
| | - Su Mya Mya Thinn
- The City College of New York, Biology Department, New York, New York, United States of America
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Chadwick AC, Jensen DR, Peterson FC, Volkman BF, Sahoo D. Expression, purification and reconstitution of the C-terminal transmembrane domain of scavenger receptor BI into detergent micelles for NMR analysis. Protein Expr Purif 2014; 107:35-42. [PMID: 25461971 DOI: 10.1016/j.pep.2014.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 10/24/2014] [Accepted: 11/04/2014] [Indexed: 01/26/2023]
Abstract
Scavenger receptor class B type I (SR-BI), the high density lipoprotein (HDL) receptor, is important for the delivery of HDL-cholesteryl esters to the liver for excretion via bile formation. The focus on therapeutic strategies aimed at reducing cholesterol levels highlights the critical need to understand the structural features of SR-BI that drive cholesterol removal. Yet, in the absence of a high-resolution structure of SR-BI, our understanding of how SR-BI interacts with HDL is limited. In this study, we have optimized the NMR solution conditions for the structural analysis of the C-terminal transmembrane domain of SR-BI that harbors putative domains required for receptor oligomerization. An isotopically-labeled SR-BI peptide encompassing residues 405-475 was bacterially-expressed and purified. [U-(15)N]-SR-BI(405-475) was incorporated into different detergent micelles and assessed by (1)H-(15)N-HSQC in order to determine which detergent micelle best maintained SR-BI(405-475) in a folded, native conformation for subsequent NMR analyses. We also determined the optimal detergent concentration used in micelles, as well as temperature, solution buffer and pH conditions. Based on (1)H-(15)N-HSQC peak dispersion, intensity, and uniformity, we determined that [U-(15)N]-SR-BI(405-475) should be incorporated into 5% detergent micelles consisting of 1-palmitoyl-2-hydroxy-sn-glycero-3-phospho-[1'-rac-glycerol] (LPPG) and data collected at 40°C in a non-buffered solution at pH 6.8. Furthermore, we demonstrate the ability of SR-BI(405-475) to form dimers upon chemical crosslinking. These studies represent the first steps in obtaining high-resolution structural information by NMR for the HDL receptor that plays a critical role in regulating whole body cholesterol removal.
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Affiliation(s)
- Alexandra C Chadwick
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Davin R Jensen
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Francis C Peterson
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| | - Daisy Sahoo
- Department of Medicine, Division of Endocrinology, Metabolism & Clinical Nutrition, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA; Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA; Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
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Kartz GA, Holme RL, Nicholson K, Sahoo D. SR-BI/CD36 chimeric receptors define extracellular subdomains of SR-BI critical for cholesterol transport. Biochemistry 2014; 53:6173-82. [PMID: 25211142 PMCID: PMC4188264 DOI: 10.1021/bi500706x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
High-density lipoproteins (HDLs) are athero-protective, primarily because of their ability to promote cholesterol flux from peripheral tissues to the liver by reverse cholesterol transport (RCT). The delivery of HDL-cholesteryl esters (CE) into cells is mediated by the HDL receptor, scavenger receptor class B type I (SR-BI), a promising target for enhancing whole body cholesterol disposal and preventing cardiovascular disease. A detailed understanding of the structural determinants underlying proper SR-BI/HDL alignment that supports the selective uptake of HDL-CE into cells remains lacking. To this end, we exploited CD36, a class B scavenger receptor with a predicted topology similar to that of SR-BI that binds HDL but is unable to mediate efficient selective uptake of HDL-CE. We generated a series of SR-BI/CD36 chimeric receptors that span the extracellular (EC) domain of SR-BI to delineate regions that are essential for SR-BI's cholesterol transport functions. All 16 SR-BI/CD36 chimeras were transiently expressed in COS-7 cells, and their plasma membrane localization was confirmed. The majority of SR-BI/CD36 chimeric receptors displayed significant reductions in their ability to (i) bind HDL, (ii) deliver HDL-CE to cells, (iii) mediate efflux of free cholesterol (FC) to HDL, and (iv) redistribute plasma membrane domains of FC. We also demonstrated that changes in SR-BI function were independent of receptor oligomerization. Altogether, we have identified discrete subdomains, particularly in the N-terminal and C-terminal regions of the EC domain of SR-BI, that are critical for productive receptor-ligand interactions and the various cholesterol transport functions of SR-BI.
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Affiliation(s)
- Gabriella A Kartz
- Departments of Pharmacology & Toxicology, ‡Biochemistry, and §Medicine, Medical College of Wisconsin , Milwaukee, Wisconsin 53226, United States
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Niemsiri V, Wang X, Pirim D, Radwan ZH, Hokanson JE, Hamman RF, Barmada MM, Demirci FY, Kamboh MI. Impact of genetic variants in human scavenger receptor class B type I (SCARB1) on plasma lipid traits. ACTA ACUST UNITED AC 2014; 7:838-47. [PMID: 25245032 DOI: 10.1161/circgenetics.114.000559] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Scavenger receptor class B type 1 (SCARB1) plays an important role in high-density lipoprotein cholesterol (HDL-C) metabolism in selective cholesteryl ester uptake and in free cholesterol cellular efflux. METHODS AND RESULTS This study aims to identify common (minor allele frequency ≥5%) and low-frequency/rare (minor allele frequency <5%) variants, using resequencing all 13 exons and exon-intron boundaries of SCARB1 in 95 individuals with extreme HDL-C levels selected from a population-based sample of 623 US non-Hispanic whites. The sequencing step identified 44 variants, of which 11 were novel with minor allele frequency <1%. Seventy-six variants (40 sequence variants, 32 common HapMap tag single nucleotide polymorphisms, and 4 relevant variants) were selected for genotyping in the total sample of 623 subjects followed by association analyses with lipid traits. Seven variants were nominally associated with apolipoprotein B (apoB; n=4) or HDL-C (n=3; P<0.05). Three variants associated with apoB remained significant after controlling false discovery rate. The most significant association was observed between rs4765615 and apoB (P=0.0059), while rs11057844 showed the strongest association with HDL-C (P=0.0035). A set of 17 rare variants (minor allele frequency ≤1%) showed significant association with apoB (P=0.0284). Haplotype analysis revealed 4 regions significantly associated with either apoB or HDL-C. CONCLUSIONS Our findings provide new information about the genetic role of SCARB1 in affecting plasma apoB levels in addition to its established role in HDL-C metabolism.
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Affiliation(s)
- Vipavee Niemsiri
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
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Karavia EA, Zvintzou E, Petropoulou PI, Xepapadaki E, Constantinou C, Kypreos KE. HDL quality and functionality: what can proteins and genes predict? Expert Rev Cardiovasc Ther 2014; 12:521-32. [DOI: 10.1586/14779072.2014.896741] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Chulsky S, Paland N, Lazarovich A, Fuhrman B. Urokinase-type plasminogen activator (uPA) decreases hepatic SR-BI expression and impairs HDL-mediated reverse cholesterol transport. Atherosclerosis 2014; 233:11-8. [DOI: 10.1016/j.atherosclerosis.2013.11.070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/05/2013] [Accepted: 11/27/2013] [Indexed: 11/29/2022]
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Song K, Han Y, Zhang L, Liu G, Yang P, Cheng X, Bu L, Sheng H, Qu S. ATP Synthase β-Chain Overexpression in SR-BI Knockout Mice Increases HDL Uptake and Reduces Plasma HDL Level. Int J Endocrinol 2014; 2014:356432. [PMID: 25114680 PMCID: PMC4120797 DOI: 10.1155/2014/356432] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 06/03/2014] [Accepted: 06/07/2014] [Indexed: 11/23/2022] Open
Abstract
HDL cholesterol is known to be inversely correlated with cardiovascular disease due to its diverse antiatherogenic functions. SR-BI mediates the selective uptake of HDL-C. SR-BI knockout diminishes but does not completely block the transport of HDL; other receptors may be involved. Ectopic ATP synthase β-chain in hepatocytes has been previously characterized as an apoA-I receptor, triggering HDL internalization. This study was undertaken to identify the overexpression of ectopic ATP synthase β-chain on DIL-HDL uptake in primary hepatocytes in vitro and on plasma HDL levels in SR-BI knockout mice. Human ATP synthase β-chain cDNA was delivered to the mouse liver by adenovirus and GFP adenovirus as control. The adenovirus-mediated overexpression of β-chain was identified at both mRNA and protein levels on mice liver and validated by its increasing of DiL-HDL uptake in primary hepatocytes. In response to hepatic overexpression of β-chain, plasma HDL-C levels and cholesterol were reduced in SR-BI knockout mice, compared with the control. The present data suggest that ATP synthase β-chain can serve as the endocytic receptor of HDL, and its overexpression can reduce plasma HDL-C.
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Affiliation(s)
- Kexiu Song
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
| | - Yingchun Han
- Institute of Cardiovascular Science, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing 100191, China
| | - Linhua Zhang
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
| | - Guoqing Liu
- Institute of Cardiovascular Science, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing 100191, China
| | - Peng Yang
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
| | - Xiaoyun Cheng
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
| | - Le Bu
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
| | - Hui Sheng
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
- Nanjing Medical University, Nanjing 210029, China
| | - Shen Qu
- Department of Endocrinology, Shanghai Tenth People's Hospital, Tongji University, 301 Middle Yanchang Road, Shanghai 200072, China
- Nanjing Medical University, Nanjing 210029, China
- *Shen Qu:
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Pei Y, Chen X, Aboutouk D, Fuller MT, Dadoo O, Yu P, White EJ, Igdoura SA, Trigatti BL. SR-BI in bone marrow derived cells protects mice from diet induced coronary artery atherosclerosis and myocardial infarction. PLoS One 2013; 8:e72492. [PMID: 23967310 PMCID: PMC3742605 DOI: 10.1371/journal.pone.0072492] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 07/17/2013] [Indexed: 01/01/2023] Open
Abstract
SR-BI deficient mice that are also hypomorphic for apolipoprotein E expression develop diet induced occlusive coronary artery atherosclerosis, myocardial infarction and early death. To test the role of SR-BI in bone marrow derived cells, we used bone marrow transplantation to generate SR-BI-null; apoE-hypomorphic mice in which SR-BI expression was restored solely in bone marrow derived cells. SR-BI-null; apoE-hypomorphic mice were transplanted with SR-BI+/+apoE-hypomorphic, or control, autologous SR-BI-null; apoE-hypomorphic bone marrow. Four weeks later, mice were fed a high-fat, high-cholesterol, cholate-containing diet to induce coronary artery atherosclerosis. Mice transplanted with autologous bone marrow developed extensive aortic atherosclerosis and severe occlusive coronary artery atherosclerosis after 4 weeks of feeding. This was accompanied by myocardial fibrosis and increased heart weights. In contrast, restoration of SR-BI expression in bone marrow derived-cells reduced diet induced aortic and coronary artery atherosclerosis, myocardial fibrosis and the increase in heart weights in SR-BI-null; apoE-hypomorphic mice. Restoration of SR-BI in bone marrow derived cells did not, however, affect steady state lipoprotein cholesterol levels, but did reduce plasma levels of IL-6. Monocytes from SR-BI-null mice exhibited a greater capacity to bind to VCAM-1 and ICAM-1 than those from SR-BI+/+ mice. Furthermore, restoration of SR-BI expression in bone marrow derived cells attenuated monocyte recruitment into atherosclerotic plaques in mice fed high fat, high cholesterol cholate containing diet. These data demonstrate directly that SR-BI in bone marrow-derived cells protects against both aortic and CA atherosclerosis.
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Affiliation(s)
- Ying Pei
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Xing Chen
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Dina Aboutouk
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Mark T. Fuller
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Omid Dadoo
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Pei Yu
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Elizabeth J. White
- Department of Biology and Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Suleiman A. Igdoura
- Department of Biology and Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Bernardo L. Trigatti
- Department of Biochemistry and Biomedical Sciences and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
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Abstract
HDL removes excess cholesterol from peripheral tissues and delivers it to the liver and steroidogenic tissues via selective lipid uptake without catabolism of the HDL particle itself. In addition, endocytosis of HDL holo-particles has been debated for nearly 40years. However, neither the connection between HDL endocytosis and selective lipid uptake, nor the physiological relevance of HDL uptake has been delineated clearly. This review will focus on HDL endocytosis and resecretion and its relation to cholesterol transfer. We will discuss the role of HDL endocytosis in maintaining cholesterol homeostasis in tissues and cell types involved in atherosclerosis, focusing on liver, macrophages and endothelium. We will critically summarize the current knowledge on the receptors mediating HDL endocytosis including SR-BI, F1-ATPase and CD36 and on intracellular HDL transport routes. Dependent on the tissue, HDL is either resecreted (retro-endocytosis) or degraded after endocytosis. Finally, findings on HDL transcytosis across the endothelial barrier will be summarized. We suggest that HDL endocytosis and resecretion is a rather redundant pathway under physiologic conditions. In case of disturbed lipid metabolism, however, HDL retro-endocytosis represents an alternative pathway that enables tissues to maintain cellular cholesterol homeostasis.
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Affiliation(s)
- Clemens Röhrl
- Department of Medical Chemistry, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Herbert Stangl
- Department of Medical Chemistry, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria.
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Dikkers A, Freak de Boer J, Annema W, Groen AK, Tietge UJF. Scavenger receptor BI and ABCG5/G8 differentially impact biliary sterol secretion and reverse cholesterol transport in mice. Hepatology 2013; 58:293-303. [PMID: 23401258 DOI: 10.1002/hep.26316] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 02/05/2013] [Indexed: 12/23/2022]
Abstract
UNLABELLED Biliary lipid secretion plays an important role in gallstone disease and reverse cholesterol transport (RCT). Using Sr-bI/Abcg5 double knockout mice (dko), the present study investigated the differential contribution of two of the most relevant transporters: adenosine triphosphate (ATP)-binding cassette subfamily G member 5 and 8 (ABCG5/G8) and scavenger receptor class B type I (SR-BI) to sterol metabolism and RCT. Plasma cholesterol levels increased in the following order, mainly due to differences in high density lipoprotein (HDL): Abcg5 ko < wild type < Sr-bI/Abcg5 dko < Sr-bI ko. Liver cholesterol content was elevated in Sr-bI ko only (P < 0.05). In Sr-bI/Abcg5 dko plasma plant sterols were highest, while hepatic plant sterols were lower compared with Abcg5 ko (P < 0.05). Under baseline conditions, biliary cholesterol secretion rates decreased in the following order: wild type > Sr-bI ko (-16%) > Abcg5 ko (-75%) > Sr-bI/Abcg5 dko (-94%), all at least P < 0.05, while biliary bile acid secretion did not differ between groups. However, under supraphysiological conditions, upon infusion with increasing amounts of the bile salt tauroursodeoxycholic acid, Abcg5 became fully rate-limiting for biliary cholesterol secretion. Additional in vivo macrophage-to-feces RCT studies demonstrated an almost 50% decrease in overall RCT in Sr-bI/Abcg5 dko compared with Abcg5 ko mice (P < 0.01). CONCLUSION These data demonstrate that (1) SR-BI contributes to ABCG5/G8-independent biliary cholesterol secretion under basal conditions; (2) biliary cholesterol mass secretion under maximal bile salt-stimulated conditions is fully dependent on ABCG5/G8; and (3) Sr-bI contributes to macrophage-to-feces RCT independent of Abcg5/g8.
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Affiliation(s)
- Arne Dikkers
- Department of Pediatrics, University Medical Center Groningen, University of Groningen, the Netherlands
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Yang XP, Amar MJ, Vaisman B, Bocharov AV, Vishnyakova TG, Freeman LA, Kurlander RJ, Patterson AP, Becker LC, Remaley AT. Scavenger receptor-BI is a receptor for lipoprotein(a). J Lipid Res 2013; 54:2450-7. [PMID: 23812625 DOI: 10.1194/jlr.m038877] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Scavenger receptor class B type I (SR-BI) is a multi-ligand receptor that binds a variety of lipoproteins, including high density lipoprotein (HDL) and low density lipoprotein (LDL), but lipoprotein(a) [Lp(a)] has not been investigated as a possible ligand. Stable cell lines (HEK293 and HeLa) expressing human SR-BI were incubated with protein- or lipid-labeled Lp(a) to investigate SR-BI-dependent Lp(a) cell association. SR-BI expression enhanced the association of both (125)I- and Alexa Fluor-labeled protein from Lp(a). By confocal microscopy, SR-BI was also found to promote the internalization of fluorescent lipids (BODIPY-cholesteryl ester (CE)- and DiI-labeled) from Lp(a), and by immunocytochemistry the cellular internalization of apolipoprotein(a) and apolipoprotein B. When dual-labeled ((3)H-cholesteryl ether,(125)I-protein) Lp(a) was added to cells expressing SR-BI, there was a greater relative increase in lipid uptake over protein, indicating that SR-BI mediates selective lipid uptake from Lp(a). Compared with C57BL/6 control mice, transgenic mice overexpressing human SR-BI in liver were found to have increased plasma clearance of (3)H-CE-Lp(a), whereas mouse scavenger receptor class B type I knockout (Sr-b1-KO) mice had decreased plasma clearance (fractional catabolic rate: 0.63 ± 0.08/day, 1.64 ± 0.62/day, and 4.64 ± 0.40/day for Sr-b1-KO, C57BL/6, and human scavenger receptor class B type I transgenic mice, respectively). We conclude that Lp(a) is a novel ligand for SR-BI and that SR-BI mediates selective uptake of Lp(a)-associated lipids.
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Affiliation(s)
- Xiao-Ping Yang
- Cardiology Division, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD, USA
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Bura KS, Lord C, Marshall S, McDaniel A, Thomas G, Warrier M, Zhang J, Davis MA, Sawyer JK, Shah R, Wilson MD, Dikkers A, Tietge UJF, Collet X, Rudel LL, Temel RE, Brown JM. Intestinal SR-BI does not impact cholesterol absorption or transintestinal cholesterol efflux in mice. J Lipid Res 2013; 54:1567-1577. [PMID: 23564696 DOI: 10.1194/jlr.m034454] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Reverse cholesterol transport (RCT) can proceed through the classic hepatobiliary route or through the nonbiliary transintestinal cholesterol efflux (TICE) pathway. Scavenger receptor class B type I (SR-BI) plays a critical role in the classic hepatobiliary route of RCT. However, the role of SR-BI in TICE has not been studied. To examine the role of intestinal SR-BI in TICE, sterol balance was measured in control mice and mice transgenically overexpressing SR-BI in the proximal small intestine (SR-BI(hApoCIII-ApoAIV-Tg)). SR-BI(hApoCIII-ApoAIV-Tg) mice had significantly lower plasma cholesterol levels compared with wild-type controls, yet SR-BI(hApoCIII-ApoAIV-Tg) mice had normal fractional cholesterol absorption and fecal neutral sterol excretion. Both in the absence or presence of ezetimibe, intestinal SR-BI overexpression had no impact on the amount of cholesterol excreted in the feces. To specifically study effects of intestinal SR-BI on TICE we crossed SR-BI(hApoCIII-ApoAIV-Tg) mice into a mouse model that preferentially utilized the TICE pathway for RCT (Niemann-Pick C1-like 1 liver transgenic), and likewise found no alterations in cholesterol absorption or fecal sterol excretion. Finally, mice lacking SR-BI in all tissues also exhibited normal cholesterol absorption and fecal cholesterol disposal. Collectively, these results suggest that SR-BI is not rate limiting for intestinal cholesterol absorption or for fecal neutral sterol loss through the TICE pathway.
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Affiliation(s)
- Kanwardeep S Bura
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Caleb Lord
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Stephanie Marshall
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Allison McDaniel
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Gwyn Thomas
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Manya Warrier
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Jun Zhang
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Matthew A Davis
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Janet K Sawyer
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Ramesh Shah
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Martha D Wilson
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Arne Dikkers
- Department of Pediatrics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Uwe J F Tietge
- Department of Pediatrics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Xavier Collet
- INSERM U1048, Institute of Metabolic and Cardiovascular Diseases of Rangueil Hospital, BP 84225, Toulouse, France
| | - Lawrence L Rudel
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC
| | - Ryan E Temel
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC.
| | - J Mark Brown
- Department of Pathology, Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC.
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Abstract
PURPOSE OF REVIEW The athero-protective role of scavenger receptor BI (SR-BI) is primarily attributed to its ability to selectively transfer cholesteryl esters from high-density lipoproteins (HDLs) to the liver during reverse cholesterol transport (RCT). In this review, we highlight recent findings that reveal the impact of SR-BI on lipid levels and cardiovascular disease in humans. Moreover, additional responsibilities of SR-BI in modulating adrenal and platelet function, as well as female fertility in humans, are discussed. RECENT FINDINGS Heterozygote carriers of P297S, S112F and T175A-mutant SR-BI receptors were identified in patients with high HDL-cholesterol levels. HDL from P297S-SR-BI carriers was unable to mediate macrophage cholesterol efflux, whereas hepatocytes expressing P297S-SR-BI were unable to mediate the selective uptake of HDL-cholesteryl esters. S112F and T175A-mutant receptors exhibited similar impaired cholesterol transport functions in vitro. Reduced SR-BI function in P297S carriers was also associated with decreased steroidogenesis and altered platelet function. Further, human population studies identified SCARB1 variants associated with female infertility. SUMMARY Identification of SR-BI variants confirms the key role of this receptor in influencing lipid levels and RCT in humans. A deeper understanding of the contributions of SR-BI to steroidogenesis, platelet function and fertility is required in light of exploration of HDL-raising therapies aimed at reducing cardiovascular risk.
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Affiliation(s)
- Alexandra C. Chadwick
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA
| | - Daisy Sahoo
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA
- Department of Medicine, Division of Endocrinology, Metabolism & Clinical Nutrition, Milwaukee, WI, 53226, USA
- To whom correspondence should be addressed: H4930 Health Research Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, Phone: 1-414-955-7414; Fax: 1-414-456-6570,
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Stanislovaitiene D, Lesauskaite V, Zaliuniene D, Smalinskiene A, Gustiene O, Zaliaduonyte-Peksiene D, Tamosiunas A, Luksiene D, Petkeviciene J, Zaliunas R. SCARB1 single nucleotide polymorphism (rs5888) is associated with serum lipid profile and myocardial infarction in an age- and gender-dependent manner. Lipids Health Dis 2013; 12:24. [PMID: 23510561 PMCID: PMC3599926 DOI: 10.1186/1476-511x-12-24] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 02/28/2013] [Indexed: 01/28/2023] Open
Abstract
Background Mutation in SCARB1 gene, exon 8 rs5888, has been associated with altered lipid levels and cardiovascular risk in humans though the results have been inconsistent. We analysed the impact of SCARB1 single nucleotide polymorphism (SNP) rs5888 with plasma lipid profile and association with coronary artery disease (CAD) in a Lithuanian population characterized by high morbidity and mortality from CAD and high prevalence of hypercholesterolemia. Methods The study included 1976 subjects from a random sample (reference group) and an myocardial infarction (MI) group of 463 patients. Genotyping of SCARB1 (rs5888) was carried out using the real-time polymerase chain reaction method. Results/principal findings Analysis of rs5888 C/T gene polymorphism in the reference group revealed that male TT genotype carriers (25–74 years) had significantly higher total cholesterol and triglyceride concentrations (5.70 mmol/l vs. 5.49 mmol/l; p = 0.036, and 1.70 mmol/l vs. 1.40 mmol/l, p = 0.023, respectively) than CT carriers and the oldest males (65–74 years) TT carriers had significantly higher high density lipoprotein cholesterol concentrations in comparison to heterozygous (1.52 mmol/l vs. 1.36 mmol/l, p = 0.033). The youngest female (25–44 years) TT genotype carriers had significantly lower low density lipoprotein cholesterol concentrations in comparison to C homozygous (2.59 mmol/l vs. 2.92 mmol/l, p = 0.023). The frequency of the SCARB1 TT genotype in the oldest male MI group (65–74 years) was significantly lower than in the corresponding reference group subjects (9.4% vs. 22.3%, p = 0.006). SCARB1 TT genotype was associated with decreased odds of MI in males aged 65–75 years (OR = 0.24, 95% CI 0.10-0.56, p = 0.001). Conclusions/significance SCARB1 polymorphism is associated with lipid metabolism and CAD in an age- and gender- dependent manner. Analysis of SCARB1 SNP rs5888 C/T genotypes revealed an atheroprotective phenotype of lipid profile in older men and in young women TT genotype carriers in the reference group. SCARB1 TT genotype was associated with decreased odds of MI in aged men.
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Affiliation(s)
- Daiva Stanislovaitiene
- Department of Ophthalmology, Medicine Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.
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