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Li Z, Zheng D, Zhang T, Ruan S, Li N, Yu Y, Peng Y, Wang D. The roles of nuclear receptors in cholesterol metabolism and reverse cholesterol transport in nonalcoholic fatty liver disease. Hepatol Commun 2024; 8:e0343. [PMID: 38099854 PMCID: PMC10727660 DOI: 10.1097/hc9.0000000000000343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/28/2023] [Indexed: 12/18/2023] Open
Abstract
As the most prevalent chronic liver disease globally, NAFLD encompasses a pathological process that ranges from simple steatosis to NASH, fibrosis, cirrhosis, and HCC, closely associated with numerous extrahepatic diseases. While the initial etiology was believed to be hepatocyte injury caused by lipid toxicity from accumulated triglycerides, recent studies suggest that an imbalance of cholesterol homeostasis is of greater significance. The role of nuclear receptors in regulating liver cholesterol homeostasis has been demonstrated to be crucial. This review summarizes the roles and regulatory mechanisms of nuclear receptors in the 3 main aspects of cholesterol production, excretion, and storage in the liver, as well as their cross talk in reverse cholesterol transport. It is hoped that this review will offer new insights and theoretical foundations for the study of the pathogenesis and progression of NAFLD and provide new research directions for extrahepatic diseases associated with NAFLD.
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Iyer DR, Venkatraman J, Tanguy E, Vitale N, Mahapatra NR. Chromogranin A and its derived peptides: potential regulators of cholesterol homeostasis. Cell Mol Life Sci 2023; 80:271. [PMID: 37642733 PMCID: PMC11072126 DOI: 10.1007/s00018-023-04908-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/31/2023]
Abstract
Chromogranin A (CHGA), a member of the granin family of proteins, has been an attractive therapeutic target and candidate biomarker for several cardiovascular, neurological, and inflammatory disorders. The prominence of CHGA stems from the pleiotropic roles of several bioactive peptides (e.g., catestatin, pancreastatin, vasostatins) generated by its proteolytic cleavage and by their wide anatomical distribution. These peptides are emerging as novel modulators of cardiometabolic diseases that are often linked to high blood cholesterol levels. However, their impact on cholesterol homeostasis is poorly understood. The dynamic nature of cholesterol and its multitudinous roles in almost every aspect of normal body function makes it an integral component of metabolic physiology. A tightly regulated coordination of cholesterol homeostasis is imperative for proper functioning of cellular and metabolic processes. The deregulation of cholesterol levels can result in several pathophysiological states. Although studies till date suggest regulatory roles for CHGA and its derived peptides on cholesterol levels, the mechanisms by which this is achieved still remain unclear. This review aims to aggregate and consolidate the available evidence linking CHGA with cholesterol homeostasis in health and disease. In addition, we also look at common molecular regulatory factors (viz., transcription factors and microRNAs) which could govern the expression of CHGA and genes involved in cholesterol homeostasis under basal and pathological conditions. In order to gain further insights into the pathways mediating cholesterol regulation by CHGA/its derived peptides, a few prospective signaling pathways are explored, which could act as primers for future studies.
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Affiliation(s)
- Dhanya R Iyer
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Janani Venkatraman
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Emeline Tanguy
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 and Université de Strasbourg, 5 Rue Blaise Pascal, 67000, Strasbourg, France
| | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 and Université de Strasbourg, 5 Rue Blaise Pascal, 67000, Strasbourg, France.
| | - Nitish R Mahapatra
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India.
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Rosenhouse-Dantsker A, Gazgalis D, Logothetis DE. PI(4,5)P 2 and Cholesterol: Synthesis, Regulation, and Functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:3-59. [PMID: 36988876 DOI: 10.1007/978-3-031-21547-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is the most abundant membrane phosphoinositide and cholesterol is an essential component of the plasma membrane (PM). Both lipids play key roles in a variety of cellular functions including as signaling molecules and major regulators of protein function. This chapter provides an overview of these two important lipids. Starting from a brief description of their structure, synthesis, and regulation, the chapter continues to describe the primary functions and signaling processes in which PI(4,5)P2 and cholesterol are involved. While PI(4,5)P2 and cholesterol can act independently, they often act in concert or affect each other's impact. The chapters in this volume on "Cholesterol and PI(4,5)P2 in Vital Biological Functions: From Coexistence to Crosstalk" focus on the emerging relationship between cholesterol and PI(4,5)P2 in a variety of biological systems and processes. In this chapter, the next section provides examples from the ion channel field demonstrating that PI(4,5)P2 and cholesterol can act via common mechanisms. The chapter ends with a discussion of future directions.
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Affiliation(s)
| | - Dimitris Gazgalis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
| | - Diomedes E Logothetis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
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Sun Y, Li X. Cholesterol efflux mechanism revealed by structural analysis of human ABCA1 conformational states. NATURE CARDIOVASCULAR RESEARCH 2022; 1:238-245. [PMID: 37181814 PMCID: PMC10181854 DOI: 10.1038/s44161-022-00022-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
ATP-binding cassette transporter A1 (ABCA1) utilizes energy derived from ATP hydrolysis to export cholesterol and phospholipids from macrophages. ABCA1 plays a central role in the biosynthesis of high-density lipoprotein (HDL), which mediates reverse cholesterol transport and prevents detrimental lipid deposition. Mutations in ABCA1 cause Tangier disease characterized by a remarkable reduction in the amount of HDL in blood. Here we present cryo-electron microscopy structures of human ABCA1 in ATP-bound and nucleotide-free states. Structural comparison reveals that ATP molecules pull the nucleotide-binding domains together, inducing movements of transmembrane helices 1, 2, 7 and 8 through a series of salt-bridge interactions. Subsequently, extracellular domains (ECDs) undergo a rotation and introduce conformational changes in the ECD-transmembrane interface. In addition, while we observe a sterol-like molecule in ECDs, no such density was observed in the structure of an HDL-deficiency mutant ABCA1Y482C, demonstrating the physiological importance of ECDs and a putative interaction mode between ABCA1 and its lipid acceptors. Thus, these structures, along with cholesterol efflux assays, advance the understanding ABCA1-mediated reverse cholesterol transport.
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Affiliation(s)
- Yingyuan Sun
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Correspondence and requests for materials should be addressed to Xiaochun Li.
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Agouridis AP, Pagkali A, Zintzaras E, Rizos EC, Ntzani EE. High-density lipoprotein cholesterol: A marker of COVID-19 infection severity? ATHEROSCLEROSIS PLUS 2021; 44:1-9. [PMID: 34622242 PMCID: PMC8383482 DOI: 10.1016/j.athplu.2021.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/01/2021] [Accepted: 08/23/2021] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND AIMS To systematically address all the relevant evidence of the association between high-density lipoprotein cholesterol (HDL-C) and COVID-19 infection. METHODS We searched PubMed, PubMed Central and medRxiv databases (up to May 2021) for studies related to HDL-C and COVID-19 infection. A qualitative synthesis of published prospective and retrospective studies for the role of low HDL-C levels on COVID-19 infection severity was performed. RESULTS Thirty-three studies (6 prospective, 27 retrospective) including 11,918 COVID-19 patients were eligible for the systematic review. Twelve studies compared HDL-C levels on admission in COVID-19 patients with healthy controls. In these 12 studies, COVID-19 patients had significantly lower HDL-C levels on admission compared with that of healthy controls. Twenty-eight studies observed the HDL-C levels among COVID-19 diagnosed patients, to establish the role of low HDL-C values in the prognosis of the infection. Twenty-four studies showed a correlation between low HDL-C levels with disease severity, while only 4 studies showed no association. CONCLUSIONS Low HDL-C levels should be added in the list of the others well-known risk factors for COVID-19 severity.
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Affiliation(s)
- Aris P. Agouridis
- School of Medicine, European University Cyprus, Nicosia, Cyprus,Department of Biomathematics, School of Medicine, University of Thessaly, Larissa, Greece,Corresponding author. Internal Medicine/Pathophysiology, School of Medicine, European University Cyprus, Diogenis Str 6, Nicosia, 2404, Cyprus
| | - Antonia Pagkali
- School of Medicine, European University Cyprus, Nicosia, Cyprus
| | - Elias Zintzaras
- Department of Biomathematics, School of Medicine, University of Thessaly, Larissa, Greece
| | - Evangelos C. Rizos
- School of Medicine, European University Cyprus, Nicosia, Cyprus,Department of Internal Medicine, University Hospital of Ioannina, Ioannina, Greece
| | - Evangelia E. Ntzani
- Department of Biomathematics, School of Medicine, University of Thessaly, Larissa, Greece,Clinical and Molecular Epidemiology Unit, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina, Greece
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6
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Mechanisms and regulation of cholesterol homeostasis. Nat Rev Mol Cell Biol 2019; 21:225-245. [DOI: 10.1038/s41580-019-0190-7] [Citation(s) in RCA: 450] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2019] [Indexed: 12/14/2022]
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Chen L, Chen XW, Huang X, Song BL, Wang Y, Wang Y. Regulation of glucose and lipid metabolism in health and disease. SCIENCE CHINA-LIFE SCIENCES 2019; 62:1420-1458. [PMID: 31686320 DOI: 10.1007/s11427-019-1563-3] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 10/15/2019] [Indexed: 02/08/2023]
Abstract
Glucose and fatty acids are the major sources of energy for human body. Cholesterol, the most abundant sterol in mammals, is a key component of cell membranes although it does not generate ATP. The metabolisms of glucose, fatty acids and cholesterol are often intertwined and regulated. For example, glucose can be converted to fatty acids and cholesterol through de novo lipid biosynthesis pathways. Excessive lipids are secreted in lipoproteins or stored in lipid droplets. The metabolites of glucose and lipids are dynamically transported intercellularly and intracellularly, and then converted to other molecules in specific compartments. The disorders of glucose and lipid metabolism result in severe diseases including cardiovascular disease, diabetes and fatty liver. This review summarizes the major metabolic aspects of glucose and lipid, and their regulations in the context of physiology and diseases.
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Affiliation(s)
- Ligong Chen
- School of Pharmaceutical Sciences, Beijing Advanced Innovation Center for Structural Biology, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing, 100084, China.
| | - Xiao-Wei Chen
- State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| | - Xun Huang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Bao-Liang Song
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| | - Yan Wang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| | - Yiguo Wang
- MOE Key Laboratory of Bioinformatics, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
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Mercan M, Yayla V, Altinay S, Seyhan S. Peripheral neuropathy in Tangier disease: A literature review and assessment. J Peripher Nerv Syst 2018; 23:88-98. [PMID: 29582519 DOI: 10.1111/jns.12265] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/15/2018] [Accepted: 03/23/2018] [Indexed: 11/29/2022]
Abstract
Tangier disease (TD) (OMIM#205400) is a rare cause of inherited metabolic neuropathies characterized by marked deficiency of high-density lipoproteins and accumulation of cholesterol esters in various tissue resulting from reverse cholesterol transport deficiency. We report a case of a patient with TD with multifocal demyelinating neuropathy with conduction block who presents with winging scapula, tongue, and asymmetric extremity weakness. We also present a review of all studies published from 1960 to 2017 regarding peripheral neuropathy in TD. Our search identified 54 patients with TD with peripheral neuropathy. Syringomyelia-like neuropathy subtype (52.4%) was more frequent than multifocal sensorial and motor neuropathy subtype (26.2%), focal neuropathy subtype (19.1%), and distal symmetric polyneuropathy subtype (2.4%). Splenomegaly was the most common (40.7%) clinical manifestation in these patients. The pattern of electrodiagnostic abnormalities are: (1) demyelinating abnormalities were more predominant in the upper extremities than in the lower extremities and (2) slowing of motor nerve conduction was more prominent in the intermediate segment than in distal nerve segments. The sural-sparing pattern was present in 34.6% and conduction block was present in 11.5% of the patients. Our literature review and our case showed the clinical spectrum of TD neuropathy is quite wide and that it should be considered in the differential diagnosis of non-uniform demyelinating neuropathies.
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Affiliation(s)
- Metin Mercan
- Department of Neurology, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, Istanbul, Turkey
| | - Vildan Yayla
- Department of Neurology, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, Istanbul, Turkey
| | - Serdar Altinay
- Department of Pathology, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, Istanbul, Turkey
| | - Serhat Seyhan
- Department of Molecular Medicine, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, Istanbul, Turkey
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Krehbiel KA, Glew RH, Modi S, Vasef MA. Splenic sea-blue (ceroid) histiocytosis due to hypertriglyceridemia: Report of a case and review of literature. HUMAN PATHOLOGY: CASE REPORTS 2017. [DOI: 10.1016/j.ehpc.2016.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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10
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Kolovou V, Marvaki A, Boutsikou M, Vasilopoulos G, Degiannis D, Marvaki C, Kolovou G. Effect of ATP-binding Cassette Transporter A1 (ABCA1) Gene Polymorphisms on Plasma Lipid Variables and Common Demographic Parameters in Greek Nurses. Open Cardiovasc Med J 2016; 10:233-239. [PMID: 27990182 PMCID: PMC5120382 DOI: 10.2174/1874192401610010233] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 09/20/2015] [Accepted: 10/22/2015] [Indexed: 12/03/2022] Open
Abstract
Objective: The present study is on line with our previous studies evaluating the influence of ATP-binding cassette transporter A1 (ABCA1) gene polymorphisms on the lipid variables of Greek student-nurses. The current study was undertaken to (1) estimate the influence of variant(s) such as rs2066715 (V825I), R219K, R1587K, I883M of ABCA1 gene on lipid variables and (2) evaluate the effect of all four ABCA1 polymorphisms on common demographic parameters. Methods: The study population involved 432 unrelated nurses (86 men) who were genotyped for ABCA1 polymorphisms and correlated according to lipid variables [total cholesterol (TC), triglycerides (TGs), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and apolipoprotein (apo) A] and demographic parameters (age, gender, BMI, waist circumference). Results: According to lipid variables concentration there was no difference between genotypes and alleles of V825I, R219K and I883M polymorphisms. The LDL-C concentration was 13% lower in RR compared with RK genotype (100.7 vs. 113.9 mg/dl, p=0.013) of R1587K gene polymorphism. In regression analysis the effects of age, gender and only R1587K gene polymorphism on LDL-C concentrations were proved significant. Additionally, LDL-C was increased (by 1.29 mg/dl on average) by every year of increase of age. Moreover, females had lower LDL-C concentrations as compared with males. Conclusion: Findings suggested that only R1587K polymorphism of ABCA1 gene was associated with lipid variables, age, and gender of Greek nurses. These findings may be helpful in assessing the risk factors for premature coronary heart disease and distinct individuals with lower/higher atherosclerotic burden.
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Affiliation(s)
- Vana Kolovou
- Molecular Immunology Laboratory, Onassis Cardiac Surgery Center, Athens, Greece
| | - Apostolia Marvaki
- Molecular Immunology Laboratory, Onassis Cardiac Surgery Center, Athens, Greece
| | - Maria Boutsikou
- Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | | | - Dimitrios Degiannis
- Molecular Immunology Laboratory, Onassis Cardiac Surgery Center, Athens, Greece
| | - Christina Marvaki
- Department of Nursing, A' Technological Educational Institute of Athens, Greece
| | - Genovefa Kolovou
- Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece
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Genetic Variants Associated with Lipid Profiles in Chinese Patients with Type 2 Diabetes. PLoS One 2015; 10:e0135145. [PMID: 26252223 PMCID: PMC4529182 DOI: 10.1371/journal.pone.0135145] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 07/17/2015] [Indexed: 11/30/2022] Open
Abstract
Dyslipidemia is a strong risk factor for cardiovascular disease among patients with type 2 diabetes (T2D). The aim of this study was to identify lipid-related genetic variants in T2D patients of Han Chinese ancestry. Among 4,908 Chinese T2D patients who were not taking lipid-lowering medications, single nucleotide polymorphisms (SNPs) in seven genes previously found to be associated with lipid traits in genome-wide association studies conducted in populations of European ancestry (ABCA1, GCKR, BAZ1B, TOMM40, DOCK7, HNF1A, and HNF4A) were genotyped. After adjusting for multiple covariates, SNPs in ABCA1, GCKR, BAZ1B, TOMM40, and HNF1A were identified as significantly associated with triglyceride levels in T2D patients (P < 0.05). The associations between the SNPs in ABCA1 (rs3890182), GCKR (rs780094), and BAZ1B (rs2240466) remained significant even after correction for multiple testing (P = 8.85×10−3, 7.88×10−7, and 2.03×10−6, respectively). BAZ1B (rs2240466) also was associated with the total cholesterol level (P = 4.75×10−2). In addition, SNP rs157580 in TOMM40 was associated with the low-density lipoprotein cholesterol level (P = 6.94×10−3). Our findings confirm that lipid-related genetic loci are associated with lipid profiles in Chinese patients with type 2 diabetes.
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Platt FM, Wassif C, Colaco A, Dardis A, Lloyd-Evans E, Bembi B, Porter FD. Disorders of cholesterol metabolism and their unanticipated convergent mechanisms of disease. Annu Rev Genomics Hum Genet 2015; 15:173-94. [PMID: 25184529 DOI: 10.1146/annurev-genom-091212-153412] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Cholesterol plays a key role in many cellular processes, and is generated by cells through de novo biosynthesis or acquired from exogenous sources through the uptake of low-density lipoproteins. Cholesterol biosynthesis is a complex, multienzyme-catalyzed pathway involving a series of sequentially acting enzymes. Inherited defects in genes encoding cholesterol biosynthetic enzymes or other regulators of cholesterol homeostasis result in severe metabolic diseases, many of which are rare in the general population and currently without effective therapy. Historically, these diseases have been viewed as discrete disorders, each with its own genetic cause and distinct pathogenic cascades that lead to its specific clinical features. However, studies have recently shown that three of these diseases have an unanticipated mechanistic convergence. This surprising finding is not only shedding light on details of cellular cholesterol homeostasis but also suggesting novel approaches to therapy.
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Affiliation(s)
- Frances M Platt
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, United Kingdom;
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13
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Wong JH, Halliday GM, Kim WS. Exploring myelin dysfunction in multiple system atrophy. Exp Neurobiol 2014; 23:337-44. [PMID: 25548533 PMCID: PMC4276804 DOI: 10.5607/en.2014.23.4.337] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/15/2014] [Accepted: 10/15/2014] [Indexed: 11/19/2022] Open
Abstract
Multiple system atrophy (MSA) is a rare, yet fatal neurodegenerative disease that presents clinically with autonomic failure in combination with parkinsonism or cerebellar ataxia. MSA impacts on the autonomic nervous system affecting blood pressure, heart rate and bladder function, and the motor system affecting balance and muscle movement. The cause of MSA is unknown, no definitive risk factors have been identified, and there is no cure or effective treatment. The definitive pathology of MSA is the presence of α-synuclein aggregates in the brain and therefore MSA is classified as an α-synucleinopathy, together with Parkinson's disease and dementia with Lewy bodies. Although the molecular mechanisms of misfolding, fibrillation and aggregation of α-synuclein partly overlap with other α-synucleinopathies, the pathological pathway of MSA is unique in that the principal site for α-synuclein deposition is in the oligodendrocytes rather than the neurons. The sequence of pathological events of MSA is now recognized as abnormal protein redistributions in oligodendrocytes first, followed by myelin dysfunction and then neurodegeneration. Oligodendrocytes are responsible for the production and maintenance of myelin, the specialized lipid membrane that encases the axons of all neurons in the brain. Myelin is composed of lipids and two prominent proteins, myelin basic protein and proteolipid protein. In vitro studies suggest that aberration in protein distribution and lipid transport may lead to myelin dysfunction in MSA. The purpose of this perspective is to bring together available evidence to explore the potential role of α-synuclein, myelin protein dysfunction, lipid dyshomeostasis and ABCA8 in MSA pathogenesis.
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Affiliation(s)
- Joanna H Wong
- Neuroscience Research Australia, Sydney, NSW 2031, Australia. ; School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Glenda M Halliday
- Neuroscience Research Australia, Sydney, NSW 2031, Australia. ; School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Woojin Scott Kim
- Neuroscience Research Australia, Sydney, NSW 2031, Australia. ; School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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14
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Marvaki A, Kolovou V, Katsiki N, Boutsikou M, Kotanidou A, Orfanos S, Filippatos G, Marvaki K, Koumoulidis A, Mavrogeni S, Kolovou G. Impact of 3 Common ABCA1 Gene Polymorphisms on Optimal vs Non-Optimal Lipid Profile in Greek Young Nurses. Open Cardiovasc Med J 2014; 8:83-7. [PMID: 25279016 PMCID: PMC4181169 DOI: 10.2174/1874192401408010083] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/24/2013] [Accepted: 11/28/2013] [Indexed: 11/22/2022] Open
Abstract
Objective: This study is in line with two previous ones from our group. They evaluated the influence of ATP-binding cassette transporter A1 (ABCA1) gene polymorphisms [such as rs2230806 (R219K), rs2230808 (R1587K) and rs4149313 (I883M)] on the human lipid profile (defined as Optimal and Non-Optimal). Methods: The present study included 447 unrelated young women and men self-reported as being healthy and that attended the University of Nursing of Technological and Educational Institution. All subjects were genotyped and the ABCA1 polymorphisms (R219K, R1587K and I883M) were recorded. According to lipid profile [total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol (LDL-C)] the subjects were separated into those with optimal lipid profile (Optimal Group, n=209) and Non-Optimal Group (n=238). Results: No statistical differences were observed in the distribution of R219K, R1587K and I883M polymorphisms according to the lipid profile (p>0.05 in all cases). No statistical differences were observed in the distribution of R219K, R1587K and I883M polymorphisms according to sex (p>0.05 in all cases). However, Logistic Regression revealed that subjects with RK (R1587K polymorphism) genotype had 69% increased risk on average of having LDL-C above normal limits as compared with those with RR genotype. Similarly, subjects with K allele (R1587K polymorphism) had 59% increased risk on average of having LDL-C above normal limits compared with those with R allele. Conclusion: These findings suggest that R1587K polymorphism of ABCA1 gene may influence the lipid profile. However, this needs to be confirmed by larger studies.
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Affiliation(s)
- Apostolia Marvaki
- Molecular Immunology Laboratory ; Onassis Cardiac Surgery Center Athens, Greece
| | | | - Niki Katsiki
- 2nd Propedeutic Department of Internal Medicine, Medical School, Aristotle University of Thessaloniki, Hippocration Hospital, Thessaloniki, Greece
| | | | - Anastasia Kotanidou
- 1stDepartment of Critical Care Medicine and Pulmonary Services, Medical School of Athens, Greece
| | - Stylianos Orfanos
- 2ndDepartment of Critical Care Medicine, Medical School of Athens, Greece
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15
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Szántó M, Brunyánszki A, Márton J, Vámosi G, Nagy L, Fodor T, Kiss B, Virág L, Gergely P, Bai P. Deletion of PARP-2 induces hepatic cholesterol accumulation and decrease in HDL levels. Biochim Biophys Acta Mol Basis Dis 2013; 1842:594-602. [PMID: 24365238 DOI: 10.1016/j.bbadis.2013.12.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 12/07/2013] [Accepted: 12/13/2013] [Indexed: 12/11/2022]
Abstract
Poly(ADP-ribose) polymerase-2 (PARP-2) is acknowledged as a DNA repair enzyme. However, recent investigations have attributed unique roles to PARP-2 in metabolic regulation in the liver. We assessed changes in hepatic lipid homeostasis upon the deletion of PARP-2 and found that cholesterol levels were higher in PARP-2(-/-) mice as compared to wild-type littermates. To uncover the molecular background, we analyzed changes in steady-state mRNA levels upon the knockdown of PARP-2 in HepG2 cells and in murine liver that revealed higher expression of sterol-regulatory element binding protein (SREBP)-1 dependent genes. We demonstrated that PARP-2 is a suppressor of the SREBP1 promoter, and the suppression of the SREBP1 gene depends on the enzymatic activation of PARP-2. Consequently, the knockdown of PARP-2 enhances SREBP1 expression that in turn induces the genes driven by SREBP1 culminating in higher hepatic cholesterol content. We did not detect hypercholesterolemia, higher fecal cholesterol content or increase in serum LDL, although serum HDL levels decreased in the PARP-2(-/-) mice. In cells and mice where PARP-2 was deleted we observed decreased ABCA1 mRNA and protein expression that is probably linked to lower HDL levels. In our current study we show that PARP-2 impacts on hepatic and systemic cholesterol homeostasis. Furthermore, the depletion of PARP-2 leads to lower HDL levels which represent a risk factor to cardiovascular diseases.
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Affiliation(s)
- Magdolna Szántó
- MTA-DE Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, 4032 Debrecen, Hungary; Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Attila Brunyánszki
- MTA-DE Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, 4032 Debrecen, Hungary
| | - Judit Márton
- Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - György Vámosi
- Department of Biophysics and Cell Biology, University of Debrecen, 4032 Debrecen, Hungary
| | - Lilla Nagy
- Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Fodor
- Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Borbála Kiss
- Department of Dermatology, Medical and Health Science Center, University of Debrecen, 4032 Debrecen, Hungary
| | - László Virág
- MTA-DE Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, 4032 Debrecen, Hungary; Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Pál Gergely
- Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Péter Bai
- MTA-DE Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, 4032 Debrecen, Hungary; Department of Medical Chemistry, University of Debrecen, 4032 Debrecen, Hungary.
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Hung YH, Bush AI, La Fontaine S. Links between copper and cholesterol in Alzheimer's disease. Front Physiol 2013; 4:111. [PMID: 23720634 PMCID: PMC3655288 DOI: 10.3389/fphys.2013.00111] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 04/30/2013] [Indexed: 01/01/2023] Open
Abstract
Altered copper homeostasis and hypercholesterolemia have been identified independently as risk factors for Alzheimer's disease (AD). Abnormal copper and cholesterol metabolism are implicated in the genesis of amyloid plaques and neurofibrillary tangles (NFT), which are two key pathological signatures of AD. Amyloidogenic processing of a sub-population of amyloid precursor protein (APP) that produces Aβ occurs in cholesterol-rich lipid rafts in copper deficient AD brains. Co-localization of Aβ and a paradoxical high concentration of copper in lipid rafts fosters the formation of neurotoxic Aβ:copper complexes. These complexes can catalytically oxidize cholesterol to generate H2O2, oxysterols and other lipid peroxidation products that accumulate in brains of AD cases and transgenic mouse models. Tau, the core protein component of NFTs, is sensitive to interactions with copper and cholesterol, which trigger a cascade of hyperphosphorylation and aggregation preceding the generation of NFTs. Here we present an overview of copper and cholesterol metabolism in the brain, and how their integrated failure contributes to development of AD.
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Affiliation(s)
- Ya Hui Hung
- Oxidation Biology Laboratory, Florey Institute of Neuroscience and Mental Health Parkville, VIC, Australia ; Centre for Neuroscience Research, The University of Melbourne Parkville, VIC, Australia
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17
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Histiocytic disorders of the gastrointestinal tract. Hum Pathol 2013; 44:683-96. [DOI: 10.1016/j.humpath.2012.05.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 05/12/2012] [Accepted: 05/16/2012] [Indexed: 12/27/2022]
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18
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Peter C, Waibel M, Keppeler H, Lehmann R, Xu G, Halama A, Adamski J, Schulze-Osthoff K, Wesselborg S, Lauber K. Release of lysophospholipid 'find-me' signals during apoptosis requires the ATP-binding cassette transporter A1. Autoimmunity 2012; 45:568-73. [PMID: 22913458 DOI: 10.3109/08916934.2012.719947] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Efficient engulfment of apoptotic cells is essential in multi-cellular organisms in order to prevent inflammatory responses. Apoptotic cells secure this process by releasing 'find-me' signals for the attraction of phagocytes. A major 'find-me' signal liberated from apoptotic cells is lysophosphatidylcholine (LPC). So far, however, the mechanisms underlying LPC release are poorly understood. In this study, we demonstrate that pharmacological inhibition and RNAi-mediated knock-down of the lipid transporter ABCA1 in apoptotic cells completely abolished phagocyte attraction. Moreover, ectopic expression of ABCA1 significantly enhanced monocyte migration to supernatants of apoptotic cells. Hence, ABCA1 represents a novel regulator of LPC release during apoptosis.
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Affiliation(s)
- Christoph Peter
- Department of Internal Medicine I, University of Tuebingen, Tuebingen, Germany
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19
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Kolovou V, Papakonstantinou VD, Stamatakis G, Verouti SN, Xanthopoulou MN, Kolovou G, Demopoulos CA. Platelet activating factor levels and metabolism in Tangier disease: a case study. Lipids Health Dis 2012; 11:89. [PMID: 22769014 PMCID: PMC3499335 DOI: 10.1186/1476-511x-11-89] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 06/25/2012] [Indexed: 11/27/2022] Open
Abstract
Background Tangier disease (TD) is a phenotypic expression of rare familial syndrome with mutations in the ABCA1 transporter. The risk of coronary artery disease in patients with TD is variable. On the other hand the pivotal role of Platelet-Activating Factor (PAF) mediator in atheromatosis was found. Plasma lipoproteins are transporters of the PAF acetylhydrolase (PAF-AH) in cells and known as lipoprotein-phospholipase A2 (Lp-PLA2) in plasma and regulators of PAF levels in blood. In addition, PAF can be biosynthesized from the remodeling and the de novo pathways in which Lyso-platelet activating factor-acetyltransferase (Lyso-PAF-AT) and platelet activating factor-cholinephosphotransferase (PAF-CPT) are the regulatory enzymes. The aim of this study is to investigate in a TD patient with a unique mutation (C2033A), the concentration of PAF in blood, the Equivalent Concentration for 50% aggregation (EC50) values of platelet rich plasma (PRP) toward PAF, adenosine diphosphate (ADP) and thrombin, and the activities of PAF metabolic enzymes Lp-PLA2, PAF-AH, Lyso-PAF-AT and PAF-CPT. Methods The EC50 value of PRP was measured by an aggregometer. The determination of the specific activity of PAF-CPT and Lyso-PAF-AT was made after in vitro enzymatic assay, chromatographic separation and measurement of the produced PAF in a biological assay with washed rabbit platelets. The determination of PAF-AH and Lp-PLA2 was made after an in vitro enzymatic assay from the decay of radioactive PAF. Results The TD patient had lower bound-PAF values in blood, decreased specific activity of PAF-CPT and Lyso-PAF-AT, increased specific activity of PAF-AH in platelets and leukocytes and Lp-PLA2 activity in plasma compared to healthy women. The EC50 of PAF and Thrombin were higher compared to healthy women. Conclusion The increased Lp-PLA2 activity, as well as, the decreased activities of PAF-CPT and Lyso-PAF-AT, explain the decreased bound-PAF level in TD patient and the EC50 of PAF. However, total PAF is in a normal range and this probably can explain one of the reasons this TD patient has no CAD.
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Affiliation(s)
- Vana Kolovou
- Cardiology Department and Molecular Immunology Laboratory, Onassis Cardiac Surgery Center, Athens, Greece.
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20
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Kolovou G, Vasiliadis I, Kolovou V, Karakosta A, Mavrogeni S, Papadopoulou E, Papamentzelopoulos S, Giannakopoulou V, Marvaki A, Degiannis D, Bilianou H. The role of common variants of the cholesteryl ester transfer protein gene in left main coronary artery disease. Lipids Health Dis 2011; 10:156. [PMID: 21899732 PMCID: PMC3175181 DOI: 10.1186/1476-511x-10-156] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 09/07/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The cholesteryl ester transfer protein (CETP) has a central role in the lipid metabolism and therefore may alter the susceptibility to atherosclerosis. METHODS The DNA of 471 subjects [133 subjects with angiographically documented left main coronary artery disease (LMCAD), 241 subjects with more peripheral coronary artery disease (MPCAD) and 97 subjects self reported healthy (Controls)] was analyzed for the frequency of TaqIB and I405V polymorphisms in the gene coding CETP. RESULTS There is no significant difference in CETP allele frequency or genotype distribution among LMCAD and MPCAD patients although there is statistical difference between LMCAD and Controls (p = 0.001). Specifically, patients with LMCAD and B1B1 genotype of TaqIB polymorphism were more frequent present compared to Controls (33.8% vs 22.9%, respectively). The frequency of B2B2 genotype was 3 times lower in the LMCAD group compared to Controls (10.5% vs 30.2%, respectively). In the LMCAD group the frequency of B1 allele compared to Controls was higher (62% vs 46%, respectively, p = 0.001). The relationship between TaqIB gene polymorphism and the LMCAD was independent of lipid profile, with the exception of apolipoprotein A. CONCLUSIONS These findings indicate that the TaqIB polymorphism may have potential importance in screening individuals at high risk for developing CAD. However, this polymorphism cannot distinguish between LMCAD and MPCAD. Further prospective investigations in larger populations are required to confirm these findings.
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Affiliation(s)
- Genovefa Kolovou
- 1st Cardiology Department, Onassis Cardiac Surgery Center 356, Sygrou Ave,, 176 74 Athens, Greece.
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21
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Kolovou V, Kolovou G, Marvaki A, Karakosta A, Vasilopoulos G, Kalogiani A, Degiannis D, Marvaki C, Demopoulos CA. ATP-binding cassette transporter A1 gene polymorphisms and serum lipid levels in young Greek nurses. Lipids Health Dis 2011; 10:56. [PMID: 21489276 PMCID: PMC3090361 DOI: 10.1186/1476-511x-10-56] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 04/13/2011] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE The ATP-binding cassette transporter A1 (ABCA1) is essential protein involved in lipid metabolism. The present study was undertaken to detect the possible association of polymorphisms in the ABCA1 gene [rs2230806 (R219K) and rs2230808 (R1587K)] and lipid profile in Greek young nurses. METHODS The study population consisted of 308 unrelated nurses who were genotyped and the ABCA1 polymorphisms were detected. Additionally, lipid profile [total cholesterol (TC), triglycerides (TGs), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and apolipoprotein (apo) A] was evaluated. RESULTS There was no difference in the genotypic and allelic frequencies of the R219K polymorphism according to lipid profile. The R1587K genotypes differed significantly according to TC, LDL-C and TGs concentration (p = 0.023, p = 0.014 and p = 0.047, respectively). Particularly, significant difference in TC, LDL-C and TGs concentration was detected between RK and RR genotypes (p = 0.006, p = 0.004, p = 0.014, respectively). Women with RK genotype compared to RR genotype had higher concentration of TGs (134.25 mg/dl vs 108.89 mg/dl, p = 0.014, respectively), total cholesterol (207.41 mg/dl vs 187.69 mg/dl, p = 0.006, respectively), and LDL-C (110.6 mg/dl vs 96.9 mg/dl, p = 0.004, respectively). CONCLUSIONS These findings suggest that the R1587K polymorphism of ABCA1 gene was associated with lipid profile of Greek nurses. Women with RK genotype had higher TGs, total and LDL-C concentration compared to RR genotype. These observations may be significant in assessing the risk of CAD since a 1% change in LDL-C is associated with a 1% change of cardiovascular events. Also, TGs concentration were documented to play a significant role in women. However, this needs to be confirmed by larger studies.
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Affiliation(s)
- Vana Kolovou
- Molecular Immunology Laboratory, Onassis Cardiac Surgery Center Athens, Greece
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22
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Methotrexate in atherogenesis and cholesterol metabolism. CHOLESTEROL 2011; 2011:503028. [PMID: 21490773 PMCID: PMC3070167 DOI: 10.1155/2011/503028] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/11/2011] [Accepted: 01/11/2011] [Indexed: 01/28/2023]
Abstract
Methotrexate is a disease-modifying antirheumatic drug commonly used to treat inflammatory conditions such as rheumatoid arthritis which itself is linked to increased cardiovascular risk. Treatments that target inflammation may also impact the cardiovascular system. While methotrexate improves cardiovascular risk, inhibition of the cyclooxygenase (COX)-2 enzyme promotes atherosclerosis. These opposing cardiovascular influences may arise from differing effects on the expression of proteins involved in cholesterol homeostasis. These proteins, ATP-binding cassette transporter (ABC) A1 and cholesterol 27-hydroxylase, facilitate cellular cholesterol efflux and defend against cholesterol overload. Methotrexate upregulates expression of cholesterol 27-hydroxylase and ABCA1 via adenosine release, while COX-2 inhibition downregulates these proteins. Adenosine, acting through the A(2A) and A(3) receptors, may upregulate proteins involved in reverse cholesterol transport by cAMP-PKA-CREB activation and STAT inhibition, respectively. Elucidating underlying cardiovascular mechanisms of these drugs provides a framework for developing novel cardioprotective anti-inflammatory medications, such as selective A(2A) receptor agonists.
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Dykeman EC, Sankey OF. Normal mode analysis and applications in biological physics. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:423202. [PMID: 21403307 DOI: 10.1088/0953-8984/22/42/423202] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Normal mode analysis has become a popular and often used theoretical tool in the study of functional motions in enzymes, viruses, and large protein assemblies. The use of normal modes in the study of these motions is often extremely fruitful since many of the functional motions of large proteins can be described using just a few normal modes which are intimately related to the overall structure of the protein. In this review, we present a broad overview of several popular methods used in the study of normal modes in biological physics including continuum elastic theory, the elastic network model, and a new all-atom method, recently developed, which is capable of computing a subset of the low frequency vibrational modes exactly. After a review of the various methods, we present several examples of applications of normal modes in the study of functional motions, with an emphasis on viral capsids.
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Affiliation(s)
- Eric C Dykeman
- Department of Physics, Center for Biological Physics, Arizona State University, Tempe, AZ 85287-1504, USA
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25
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Schweitzer JK, Sedgwick AE, D'Souza-Schorey C. ARF6-mediated endocytic recycling impacts cell movement, cell division and lipid homeostasis. Semin Cell Dev Biol 2010; 22:39-47. [PMID: 20837153 DOI: 10.1016/j.semcdb.2010.09.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 08/31/2010] [Accepted: 09/03/2010] [Indexed: 01/19/2023]
Abstract
A wide range of cellular activities depends upon endocytic recycling. ARF6, a small molecular weight GTPase, regulates the processes of endocytosis and endocytic recycling in concert with various effector molecules and other small GTPases. This review highlights three critical processes that involve ARF6-mediated endosomal membrane trafficking-cell motility, cytokinesis, and cholesterol homeostasis. In each case, the function of ARF6-mediated trafficking varies-including localization of specific protein and lipid cargo, regulation of bulk membrane movement, and modulation of intracellular signaling. As described in this review, mis-regulation of endocytic traffic can result in human disease when it compromises the cell's ability to regulate cell movement and invasion, cell division, and lipid homeostasis.
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Affiliation(s)
- Jill Kuglin Schweitzer
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369, USA
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26
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Basu A, Tang H, Lewis CE, North K, Curb JD, Quertermous T, Mosley TH, Boerwinkle E, Zhu X, Risch NJ. Admixture mapping of quantitative trait loci for blood lipids in African-Americans. Hum Mol Genet 2009; 18:2091-8. [PMID: 19304782 PMCID: PMC2722229 DOI: 10.1093/hmg/ddp122] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 01/29/2009] [Accepted: 03/12/2009] [Indexed: 01/19/2023] Open
Abstract
Blood lipid levels, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG), are highly heritable traits and major risk factors for atherosclerotic cardiovascular disease (CVD). Using individual ancestry estimates at marker locations across the genome, we present a novel quantitative admixture mapping analysis of all three lipid traits in a large sample of African-Americans from the Family Blood Pressure Program. Regression analysis was performed with both total and marker-location-specific European ancestry as explanatory variables, along with demographic covariates. Robust permutation analysis was used to assess statistical significance. Overall European ancestry was significantly correlated with HDL-C (negatively) and TG (positively), but not with LDL-C. We found strong evidence for a novel locus underlying HDL-C on chromosome 8q, which correlated negatively with European ancestry (P = .0014); the same location also showed positive correlation of European ancestry with TG levels. A region on chromosome 14q also showed significant negative correlation between HDL-C levels and European ancestry. On chromosome 15q, a suggestive negative correlation of European ancestry with TG and positive correlation with HDL-C was observed. Results with LDL-C were less significant overall. We also found significant evidence for genome-wide ancestry effects underlying the joint distribution of HDL-C and TG, not fully explained by the locus on chromosome 8. Our results are consistent with a genetic contribution to and may explain the healthier HDL-C and TG profiles found in Blacks versus Whites. The identified regions provide locations for follow-up studies of genetic variants underlying lipid variation in African-Americans and possibly other populations.
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Affiliation(s)
| | | | - Cora E. Lewis
- Department of Medicine, University of Alabama, Birmingham, UK
| | - Kari North
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - J. David Curb
- Department of Geriatric Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, USA
| | | | | | - Eric Boerwinkle
- School of Public Health, University of Texas Health Science Center, Houston, TX, USA
| | - Xiaofeng Zhu
- Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Neil J. Risch
- Institute for Human Genetics
- Department of Epidemiology and Biostatistics, University of California San Francisco, 513 Parnassus Avenue, Room 901F HSW, San Francisco, CA 94143, USA
- Kaiser Permanente Division of Research, Oakland, CA, USA
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27
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Abstract
The association of genetic factors and cerebral infarction (CI) has long been established. A positive family history alone is a recognized risk factor for CI and vascular events in general. However, there are certain inherited conditions that further increase the risk of stroke. These conditions are generally metabolic and mitochondrial genetic defects that have variable modes of inheritance. This article reviews major inherited metabolic disorders that predispose an individual to CI. Ten main conditions will be discussed: Fabry's disease, cerebrotendinous xanthomatosis, tangier disease, familial hypercholesterolemia, homocystinuria, methylmalonic acidemia, glutaric aciduria type I, propionic acidemia, ornithine transcarbamylase deficiency and mitochondrial encephalopathy, lactic acidosis and stroke-like phenomenon.
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Affiliation(s)
- Kavita Kalidas
- Department of Neurology, University of South Florida College of Medicine, Tampa, FL 33606, USA.
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28
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Souza-Menezes J, Morales MM. CFTR structure and function: is there a role in the kidney? Biophys Rev 2009; 1:3-12. [PMID: 28510151 DOI: 10.1007/s12551-008-0002-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Accepted: 12/19/2008] [Indexed: 12/27/2022] Open
Abstract
Cystic fibrosis (CF) is a lethal autosomal recessive genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR). Mutations in the CFTR gene may result in a defective protein processing that leads to changes in function and regulation of this chloride channel. Despite of the expression of CFTR in the kidney, patients with CF do not present major renal dysfunction, but it is known that both the urinary excretion of proteins and renal capacity to concentrate and dilute urine are altered in these patients. CFTR mRNA is expressed in all nephron segments of rat and human, and this abundance is more prominent in renal cortex and outer medulla renal areas. CFTR protein was detected in apical surface of both proximal and distal tubules of rat kidney but not in the outer medullary collecting ducts. Studies have demonstrated that CFTR does not only transport Cl- but also ATP. ATP transport by CFTR could be involved in the control of other ion transporters such as Na+ (ENaC) and K+ (renal outer medullary potassium) channels, especially in TAL and CCD. In the kidney, CFTR also might be involved in the endocytosis of low-molecular-weight proteins by proximal tubules. This review is focused on the CFTR function and structure, its role in the renal physiology, and its modulation by hormones involved in the control of extracellular fluid volume.
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Affiliation(s)
- J Souza-Menezes
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Macaé, Brazil
| | - M M Morales
- Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. .,, Av Carlos Chagas Filho 373, Centro de Ciências da Saúde Bloco G Sala 48, Cidade Universitária, Rio de Janeiro, 21941-902, Brazil.
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29
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Anderson N, Borlak J. Molecular Mechanisms and Therapeutic Targets in Steatosis and Steatohepatitis. Pharmacol Rev 2008; 60:311-57. [DOI: 10.1124/pr.108.00001] [Citation(s) in RCA: 291] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Abstract
Tangier disease is a rare genetic disorder of lipid metabolism, characterized by severe deficiency of plasma high-density lipoprotein cholesterol, low-plasma total cholesterol, and accumulation of cholesteryl ester in macrophages. Abdominal manifestation of Tangier disease is extremely rare, being reported only once in the English literature. We describe a 55-year-old patient with this condition, who underwent splenectomy 37 years before, because of splenomegaly with thrombocytopenia, and subsequently presented with abdominal pain and pancreatic mass, simulating a pancreatic tumor. The preoperative diagnosis of endocrine or solid-cystic neoplasm was made, and the tumor was successfully resected with distal pancreatectomy. Histological examination showed that the mass was composed of histiocytic cells containing lipids; some aggregates of giant polynucleated histiocytes with intracytoplasmic cholesterol crystals. To our knowledge, this is the first report of pancreatic manifestation of Tangier disease. As suggested earlier, splenectomy in these patients seems to predispose to deposition of lipids and infiltration of the abdomen by inflammatory cells.
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31
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Brown WM, Chiacchia FS. Therapies to Increase ApoA-I and HDL-Cholesterol Levels. Drug Target Insights 2008. [DOI: 10.4137/dti.s447] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- William M. Brown
- Resverlogix Corp., 202, 279 Midpark Way SE, Calgary, AB T2X 1M2, Canada
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32
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Abstract
CLC-0 and cystic fibrosis transmembrane conductance regulator (CFTR) Cl−channels play important roles in Cl−transport across cell membranes. These two proteins belong to, respectively, the CLC and ABC transport protein families whose members encompass both ion channels and transporters. Defective function of members in these two protein families causes various hereditary human diseases. Ion channels and transporters were traditionally viewed as distinct entities in membrane transport physiology, but recent discoveries have blurred the line between these two classes of membrane transport proteins. CLC-0 and CFTR can be considered operationally as ligand-gated channels, though binding of the activating ligands appears to be coupled to an irreversible gating cycle driven by an input of free energy. High-resolution crystallographic structures of bacterial CLC proteins and ABC transporters have led us to a better understanding of the gating properties for CLC and CFTR Cl−channels. Furthermore, the joined force between structural and functional studies of these two protein families has offered a unique opportunity to peek into the evolutionary link between ion channels and transporters. A promising byproduct of this exercise is a deeper mechanistic insight into how different transport proteins work at a fundamental level.
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33
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Gazi IF, Mikhailidis DP. Non-low-density lipoprotein cholesterol-associated actions of ezetimibe: an overview. Expert Opin Ther Targets 2006; 10:851-66. [PMID: 17105372 DOI: 10.1517/14728222.10.6.851] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Ezetimibe, an intestinal cholesterol absorption inhibitor, lowers circulating low-density lipoprotein cholesterol (LDL-C) levels both when administered as monotherapy and in combination with other hypolipidaemic drugs, mostly statins. This review focuses on the effects of ezetimibe on non-LDL-C-associated variables. In most studies, ezetimibe effectively reduced triglyceride and increased high density lipoprotein cholesterol levels. The authors also consider the effect of ezetimibe on other variables such as C-reactive protein levels, insulin sensitivity and endothelial function. Ezetimibe is useful in patients with sitosterolaemia (a rare inherited disorder) as it significantly reduces plasma phytosterol concentrations. Ezetimibe fulfils two of the three essential characteristics of any drug (efficacy and safety). However, clinical studies are required to provide evidence of its ability to reduce vascular events.
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Affiliation(s)
- Irene F Gazi
- Royal Free Hospital, Department of Clinical Biochemistry, Royal Free and University College of Medicine, University of London, Pond Street, London NW3 2QG, UK
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34
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Kolovou GD, Salpea KD, Anagnostopoulou KK, Mikhailidis DP. Alcohol use, vascular disease, and lipid-lowering drugs. J Pharmacol Exp Ther 2006; 318:1-7. [PMID: 16627749 DOI: 10.1124/jpet.106.102269] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Many epidemiological and clinical studies have shown that light-to-moderate alcohol (Alc) consumption is associated with reduced risk of coronary heart disease (CHD) and total mortality in middle-aged and elderly men and women. The plausible mechanisms for the putative cardioprotective effects include increased levels of high-density lipoprotein cholesterol, prevention of clot formation, reduced platelet aggregation, promotion of blood clot dissolution, and lowering of plasma lipoprotein (a) concentration. Individuals who need to be treated with lipid-lowering drugs, such as dyslipidemic or CHD patients, may benefit from these effects of Alc. Because hypolipidemic treatment is usually continued for life, an important issue is the suitability of Alc consumption in these patients. In the present review, the beneficial effects of Alc consumption on CHD risk, its side effects, and its safety and suitability when coadministered with hypolipidemic drugs are discussed.
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Affiliation(s)
- Genovefa D Kolovou
- 1st Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece, and Department of Clinical Biochemistry, Vascular Disease Prevention Clinics, Royal Free Hospital, Royal Free and University College Medical School, London, UK.
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