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Voros S, Bansal AT, Barnes MR, Narula J, Maurovich-Horvat P, Vazquez G, Marvasty IB, Brown BO, Voros ID, Harris W, Voros V, Dayspring T, Neff D, Greenfield A, Furchtgott L, Church B, Runge K, Khalil I, Hayete B, Lucero D, Remaley AT, Newton RS. Bayesian network analysis of panomic biological big data identifies the importance of triglyceride-rich LDL in atherosclerosis development. Front Cardiovasc Med 2023; 9:960419. [PMID: 36684605 PMCID: PMC9845579 DOI: 10.3389/fcvm.2022.960419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 11/23/2022] [Indexed: 01/06/2023] Open
Abstract
Introduction We sought to explore biomarkers of coronary atherosclerosis in an unbiased fashion. Methods We analyzed 665 patients (mean ± SD age, 56 ± 11 years; 47% male) from the GLOBAL clinical study (NCT01738828). Cases were defined by the presence of any discernable atherosclerotic plaque based on comprehensive cardiac computed tomography (CT). De novo Bayesian networks built out of 37,000 molecular measurements and 99 conventional biomarkers per patient examined the potential causality of specific biomarkers. Results Most highly ranked biomarkers by gradient boosting were interleukin-6, symmetric dimethylarginine, LDL-triglycerides [LDL-TG], apolipoprotein B48, palmitoleic acid, small dense LDL, alkaline phosphatase, and asymmetric dimethylarginine. In Bayesian analysis, LDL-TG was directly linked to atherosclerosis in over 95% of the ensembles. Genetic variants in the genomic region encoding hepatic lipase (LIPC) were associated with LIPC gene expression, LDL-TG levels and with atherosclerosis. Discussion Triglyceride-rich LDL particles, which can now be routinely measured with a direct homogenous assay, may play an important role in atherosclerosis development. Clinical trial registration GLOBAL clinical study (Genetic Loci and the Burden of Atherosclerotic Lesions); [https://clinicaltrials.gov/ct2/show/NCT01738828?term=NCT01738828&rank=1], identifier [NCT01738828].
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Affiliation(s)
- Szilard Voros
- Global Genomics Group, Atlanta, GA, United States,*Correspondence: Szilard Voros,
| | | | | | - Jagat Narula
- Mount Sinai School of Medicine, New York, NY, United States
| | - Pal Maurovich-Horvat
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Gustavo Vazquez
- Global Institute for Research, LLC, Richmond, VA, United States
| | | | | | | | | | - Viktor Voros
- Global Genomics Group, Atlanta, GA, United States,Department of Psychiatry, Medical School, University of Pécs, Pécs, Hungary
| | | | - David Neff
- Global Genomics Group, Atlanta, GA, United States
| | | | | | | | - Karl Runge
- GNS Healthcare, Somerville, MA, United States
| | - Iya Khalil
- GNS Healthcare, Somerville, MA, United States
| | | | - Diego Lucero
- Lipoprotein Metabolism Laboratory, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | - Alan T. Remaley
- Lipoprotein Metabolism Laboratory, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
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Berberich AJ, Hegele RA. Genetic testing in dyslipidaemia: An approach based on clinical experience. Best Pract Res Clin Endocrinol Metab 2022; 37:101720. [PMID: 36682941 DOI: 10.1016/j.beem.2022.101720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have used DNA sequencing in our lipid clinic for >20 years. Dyslipidaemia is typically ascertained biochemically. For moderate deviations in the lipid profile, the etiology is often a combination of a polygenic susceptibility component plus secondary non-genetic factors. For severe dyslipidaemia, a monogenic etiology is more likely, although a discrete single-gene cause is frequently not found. A severe phenotype can also result from strong polygenic predisposition that is aggravated by secondary factors. A young age of onset plus a family history of dyslipidaemia or atherosclerotic cardiovascular disease can suggest a monogenic etiology. With severe dyslipidaemia, clinical examination focuses on detecting manifestations of monogenic syndromic conditions. For all patients with dyslipidaemia, secondary causes must be ruled out. Here we describe an experience-based practical approach to genetic testing of patients with severe deviations of low-density lipoprotein, triglycerides, high-density lipoprotein and also combined hyperlipidaemia and dysbetalipoproteinemia.
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Affiliation(s)
- Amanda J Berberich
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St, London, ON, N6A 5C1, Canada; Western University, Division of Endocrinology & Metabolism, St. Joseph's Hospital, 268 Grosvenor Street, London, Ontario, Canada.
| | - Robert A Hegele
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St, London, ON, N6A 5C1, Canada; Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 4288A-1151 Richmond Street North, London, ON, N6A 5B7, Canada.
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3
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Heidemann BE, Koopal C, Baass A, Defesche JC, Zuurbier L, Mulder MT, Roeters van Lennep JE, Riksen NP, Boot C, Marais AD, Visseren FLJ. Establishing the relationship between Familial Dysbetalipoproteinemia and genetic variants in the APOE gene. Clin Genet 2022; 102:253-261. [PMID: 35781703 PMCID: PMC9543580 DOI: 10.1111/cge.14185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 11/30/2022]
Abstract
Familial Dysbetalipoproteinemia (FD) is the second most common monogenic dyslipidemia and is associated with a very high cardiovascular risk due to cholesterol‐enriched remnant lipoproteins. FD is usually caused by a recessively inherited variant in the APOE gene (ε2ε2), but variants with dominant inheritance have also been described. The typical dysbetalipoproteinemia phenotype has a delayed onset and requires a metabolic hit. Therefore, the diagnosis of FD should be made by demonstrating both the genotype and dysbetalipoproteinemia phenotype. Next Generation Sequencing is becoming more widely available and can reveal variants in the APOE gene for which the relation with FD is unknown or uncertain. In this article, two approaches are presented to ascertain the relationship of a new variant in the APOE gene with FD. The comprehensive approach consists of determining the pathogenicity of the variant and its causal relationship with FD by confirming a dysbetalipoproteinemia phenotype, and performing in vitro functional tests and, optionally, in vivo postprandial clearance studies. When this is not feasible, a second, pragmatic approach within reach of clinical practice can be followed for individual patients to make decisions on treatment, follow‐up, and family counseling.
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Affiliation(s)
- Britt E Heidemann
- Department of Vascular Medicine, University Medical Center Utrecht, Utrecht University, The Netherlands
| | - Charlotte Koopal
- Department of Vascular Medicine, University Medical Center Utrecht, Utrecht University, The Netherlands
| | - Alexis Baass
- Genetic Dyslipidemias Clinic of the Montreal Clinical Research Institute, Québec, Canada; Department of Medicine, Divisions of Experimental Medicine and Medical Biochemistry, McGill University, Québec, Canada
| | - Joep C Defesche
- Department of Human Genetics, Amsterdam University Medical Centers, University of Amsterdam, Netherlands
| | - Linda Zuurbier
- Department of Human Genetics, Amsterdam University Medical Centers, University of Amsterdam, Netherlands
| | - Monique T Mulder
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, Netherlands
| | | | - Niels P Riksen
- Department of Internal Medicine and Research Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Christopher Boot
- Department of Blood Sciences, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - A David Marais
- Division of Chemical Pathology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, South Africa; Cape Town, South Africa
| | - Frank L J Visseren
- Department of Vascular Medicine, University Medical Center Utrecht, Utrecht University, The Netherlands
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4
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Zhu W, Zhang Z, Gui W, Shen Z, Chen Y, Yin X, Liang L, Li L. Identification of the Key Pathways and Genes in Hypoxia Pulmonary Arterial Hypertension Following Intrauterine Growth Retardation. Front Mol Biosci 2022; 9:789736. [PMID: 35433826 PMCID: PMC9008831 DOI: 10.3389/fmolb.2022.789736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 03/08/2022] [Indexed: 11/30/2022] Open
Abstract
High-throughput sequencing and weighted gene co-expression network analysis (WGCNA) were used to identify susceptibility modules and genes in liver tissue for the hypoxic pulmonary arterial hypertension (PAH) animal model following intrauterine growth retardation (IUGR). A total of 5,000 genes were clustered into eight co-expression modules via WGCNA. Module blue was mostly significantly correlated with the IUGR–hypoxia group. Gene Ontology analysis showed that genes in the module blue were mainly enriched in the fatty acid metabolic process, lipid modification, and fatty acid catabolic process. The Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that the genes in module blue were mainly associated with fatty acid metabolism, PPAR signaling pathway, and biosynthesis of unsaturated fatty acids. In addition, the maximal clique centrality method was used to identify the hub genes in the subnetworks, and the obtained results were verified using real-time quantitative PCR. Finally, we identified that four genes including Cyp2f4, Lipc, Acadl, and Hacl1 were significantly associated with IUGR-hypoxia. Our study identified a module and several key genes that acted as essential components in the etiology of the long-term metabolic consequences in hypoxia PAH following IUGR.
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Affiliation(s)
- Weifen Zhu
- Department of Endocrinology, The Affiliated Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ziming Zhang
- Department of Neonatology, Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Weiwei Gui
- Department of Endocrinology, The Affiliated Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zheng Shen
- Department of Central Laboratory, Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Yixin Chen
- Department of Endocrinology, The Affiliated Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xueyao Yin
- Department of Endocrinology, The Affiliated Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Li Liang
- Department of Pediatrics, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Lin Li
- Department of Endocrinology, The Affiliated Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- *Correspondence: Lin Li,
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5
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Kardassis D, Thymiakou E, Chroni A. Genetics and regulation of HDL metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1867:159060. [PMID: 34624513 DOI: 10.1016/j.bbalip.2021.159060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 09/06/2021] [Accepted: 09/09/2021] [Indexed: 02/07/2023]
Abstract
The inverse association between plasma HDL cholesterol (HDL-C) levels and risk for cardiovascular disease (CVD) has been demonstrated by numerous epidemiological studies. However, efforts to reduce CVD risk by pharmaceutically manipulating HDL-C levels failed and refused the HDL hypothesis. HDL-C levels in the general population are highly heterogeneous and are determined by a combination of genetic and environmental factors. Insights into the causes of HDL-C heterogeneity came from the study of monogenic HDL deficiency syndromes but also from genome wide association and Μendelian randomization studies which revealed the contribution of a large number of loci to low or high HDL-C cases in the general or in restricted ethnic populations. Furthermore, HDL-C levels in the plasma are under the control of transcription factor families acting primarily in the liver including members of the hormone nuclear receptors (PPARs, LXRs, HNF-4) and forkhead box proteins (FOXO1-4) and activating transcription factors (ATFs). The effects of certain lipid lowering drugs used today are based on the modulation of the activity of specific members of these transcription factors. During the past decade, the roles of small or long non-coding RNAs acting post-transcriptionally on the expression of HDL genes have emerged and provided novel insights into HDL regulation and new opportunities for therapeutic interventions. In the present review we summarize recent progress made in the genetics and the regulation (transcriptional and post-transcriptional) of HDL metabolism.
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Affiliation(s)
- Dimitris Kardassis
- Laboratory of Biochemistry, Department of Basic Sciences, University of Crete Medical School and Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion, Greece.
| | - Efstathia Thymiakou
- Laboratory of Biochemistry, Department of Basic Sciences, University of Crete Medical School and Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion, Greece
| | - Angeliki Chroni
- Institute of Biosciences and Applications, National Center for Scientific Research "Demokritos", Agia Paraskevi, Athens, Greece
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6
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Successful Genetic Screening and Creating Awareness of Familial Hypercholesterolemia and Other Heritable Dyslipidemias in the Netherlands. Genes (Basel) 2021; 12:genes12081168. [PMID: 34440342 PMCID: PMC8392502 DOI: 10.3390/genes12081168] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 12/17/2022] Open
Abstract
The genetic screening program for familial hypercholesterolemia (FH) in the Netherlands, which was embraced by the Dutch Ministry of Health from 1994 to 2014, has led to twenty years of identification of at least 1500 FH cases per year. Although funding by the government was terminated in 2014, the approach had proven its effectiveness and had built the foundation for the development of more sophisticated diagnostic tools, clinical collaborations, and new molecular-based treatments for FH patients. As such, the community was driven to continue the program, insurance companies were convinced to collaborate, and multiple approaches were launched to find new index cases with FH. Additionally, the screening was extended, now also including other heritable dyslipidemias. For this purpose, a diagnostic next-generation sequencing (NGS) panel was developed, which not only comprised the culprit LDLR, APOB, and PCSK9 genes, but also 24 other genes that are causally associated with genetic dyslipidemias. Moreover, the NGS technique enabled further optimization by including pharmacogenomic genes in the panel. Using such a panel, more patients that are prone to cardiovascular diseases are being identified nowadays and receive more personalized treatment. Moreover, the NGS output teaches us more and more about the dyslipidemic landscape that is less straightforward than we originally thought. Still, continuous progress is being made that underlines the strength of genetics in dyslipidemia, such as discovery of alternative genomic pathogenic mechanisms of disease development and polygenic contribution.
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7
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May SC, Dron JS, Hegele RA, Sahoo D. Human variant of scavenger receptor BI (R174C) exhibits impaired cholesterol transport functions. J Lipid Res 2021; 62:100045. [PMID: 33577783 PMCID: PMC7985710 DOI: 10.1016/j.jlr.2021.100045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 01/22/2021] [Indexed: 11/29/2022] Open
Abstract
HDL and its primary receptor, scavenger receptor class B type I (SR-BI), work together to promote the clearance of excess plasma cholesterol, thereby protecting against atherosclerosis. Human variants of SR-BI have been identified in patients with high HDL-cholesterol levels, and at least one variant has been linked to cardiovascular disease. Therefore, while often regarded as beneficial, very high levels of HDL-cholesterol may result from impaired cholesterol clearance through SR-BI and contribute to cardiovascular risk. In this study, we characterized the function of a rare human variant of SR-BI, resulting in the substitution of arginine-174 with cysteine (R174C), which was previously identified in a heterozygous individual with high levels of HDL-cholesterol. We hypothesized that the R174C-SR-BI variant has impaired cholesterol transport functions, which were assessed in COS-7 cells after transient transfection with full-length WT or R174C-SR-BI. Although R174C-SR-BI was expressed at levels comparable to the WT receptor, HDL binding, cholesteryl hexadecyl ether uptake, free cholesterol efflux, and modulation of membrane cholesterol were disrupted in the presence of R174C-SR-BI. We further examined the role of salt bridges as a potential mechanism for R174C-SR-BI dysfunction. If translatable, this human variant could lead to increased plasma HDL-cholesterol levels, impaired cholesterol clearance, and increased cardiovascular disease risk.
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Affiliation(s)
- Sarah C May
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jacqueline S Dron
- Robarts Research Institute, Western University, London, Ontario, Canada; Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Robert A Hegele
- Robarts Research Institute, Western University, London, Ontario, Canada; Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Daisy Sahoo
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA.
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8
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Abstract
Dyslipidemias include both rare single gene disorders and common conditions that have a complex underlying basis. In London, ON, there is fortuitous close physical proximity between the Lipid Genetics Clinic and the London Regional Genomics Centre. For >30 years, we have applied DNA sequencing of clinical samples to help answer scientific questions. More than 2000 patients referred with dyslipidemias have participated in an ongoing translational research program. In 2013, we transitioned to next-generation sequencing; our targeted panel is designed to concurrently assess both monogenic and polygenic contributions to dyslipidemias. Patient DNA is screened for rare variants underlying 25 mendelian dyslipidemias, including familial hypercholesterolemia, hepatic lipase deficiency, abetalipoproteinemia, and familial chylomicronemia syndrome. Furthermore, polygenic scores for LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol, and triglycerides are calculated for each patient. We thus simultaneously document both rare and common genetic variants, allowing for a broad view of genetic predisposition for both individual patients and cohorts. For instance, among patients referred with severe hypertriglyceridemia, defined as ≥10 mmol/L (≥885 mg/dL), <1% have a mendelian disorder (ie, autosomal recessive familial chylomicronemia syndrome), ≈15% have heterozygous rare variants (a >3-fold increase over normolipidemic individuals), and ≈35% have an extreme polygenic score (a >3-fold increase over normolipidemic individuals). Other dyslipidemias show a different mix of genetic determinants. Genetic results are discussed with patients and can support clinical decision-making. Integrating DNA testing into clinical care allows for a bidirectional flow of information, which facilitates scientific discoveries and clinical translation.
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Affiliation(s)
- Robert A. Hegele
- From the Department of Medicine (R.A.H.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Department of Biochemistry (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Robarts Research Institute (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Jacqueline S. Dron
- Department of Biochemistry (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Robarts Research Institute (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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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] [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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Zago VHS, Parra ES, Virgínio VWM, Vendrame F, Gomes ÉIL, Scherrer DZ, Marson FAL, de Faria EC. Lipase C, Hepatic Type -250A/G (rs2070895) Variant Enhances Carotid Atherosclerosis in Normolipidemic and Asymptomatic Individuals from Brazil. Lipids 2020; 55:225-237. [PMID: 32196671 DOI: 10.1002/lipd.12232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 02/20/2020] [Accepted: 02/27/2020] [Indexed: 11/08/2022]
Abstract
The common genetic variant in the promoter region of the hepatic lipase gene [LIPC -250G/A(rs2070895)] has an ambiguous association with cardiovascular disease. In this context, our study was performed to identify the relationships between the rs2070895 with carotid atherosclerosis, plasma lipids, and parameters of reverse cholesterol transport. A total of 285 normolipidemic and asymptomatic participants from an initial sample of 598,288 individuals (inclusion criteria: LDL-C ≤130 mg/dL and triglycerides ≤150 mg/dL; age: 20-75 years, both genders; confirmation of clinical, anthropometric and laboratory data; attended all visits; DNA was achieved to perform genetic analysis) were enrolled and the rs2070895 variant was genotyped by TaqMan® OpenArray® Plataform. Carotid intima-media thickness and the screening of atherosclerotic plaques were determined by B-mode ultrasonography. The rs2070895 genotype frequencies were 0.44, 0.41, and 0.15 (GG, GA, and AA, respectively). Logistic regression analysis showed that the risk of having plaques was increased in participants carrying the AA or AG genotypes (OR = 3.90; 95% CI = 1.54-10.33), despite an increase in high-density lipoprotein cholesterol levels, HDL diameter and apolipoprotein A-I, as compared to the GG genotype. Hepatic lipase and endogenous lecithin cholesterol acyl transferase activities were reduced (38% and 19%, respectively) and lipoprotein lipase was increased by 30% (AA vs GG). Our results provide evidence that the AA or AG genotypes of the rs2070895 were associated with carotid atherosclerosis in apparently healthy participants, probably as a consequence of reduced reverse cholesterol transport and accumulation of HDL subfraction 2 rich in triglycerides and depleted in cholesteryl esters that could become dysfunctional.
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Affiliation(s)
- Vanessa H S Zago
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Eliane S Parra
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Vítor W M Virgínio
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Felipe Vendrame
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Érica I L Gomes
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Daniel Z Scherrer
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
| | - Fernando A L Marson
- Department of Pediatric, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil.,Department of Medical Genetics and Genomic Medicine, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil.,Laboratory of Human and Medical Genetics, Post Graduate Program in Health Science, São Francisco University, São Francisco de Assis Av, 218, Jardim São José, Bragança Paulista, São Paulo, 12916-900, Brazil
| | - Eliana C de Faria
- Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas, Tessália Vieira de Camargo St, 126, Campinas, São Paulo, 13084-971, Brazil
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11
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Hegele RA, Borén J, Ginsberg HN, Arca M, Averna M, Binder CJ, Calabresi L, Chapman MJ, Cuchel M, von Eckardstein A, Frikke-Schmidt R, Gaudet D, Hovingh GK, Kronenberg F, Lütjohann D, Parhofer KG, Raal FJ, Ray KK, Remaley AT, Stock JK, Stroes ES, Tokgözoğlu L, Catapano AL. Rare dyslipidaemias, from phenotype to genotype to management: a European Atherosclerosis Society task force consensus statement. Lancet Diabetes Endocrinol 2020; 8:50-67. [PMID: 31582260 DOI: 10.1016/s2213-8587(19)30264-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 07/23/2019] [Accepted: 07/27/2019] [Indexed: 12/18/2022]
Abstract
Genome sequencing and gene-based therapies appear poised to advance the management of rare lipoprotein disorders and associated dyslipidaemias. However, in practice, underdiagnosis and undertreatment of these disorders are common, in large part due to interindividual variability in the genetic causes and phenotypic presentation of these conditions. To address these challenges, the European Atherosclerosis Society formed a task force to provide practical clinical guidance focusing on patients with extreme concentrations (either low or high) of plasma low-density lipoprotein cholesterol, triglycerides, or high-density lipoprotein cholesterol. The task force also recognises the scarcity of quality information regarding the prevalence and outcomes of these conditions. Collaborative registries are needed to improve health policy for the care of patients with rare dyslipidaemias.
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Affiliation(s)
- Robert A Hegele
- Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.
| | - Jan Borén
- Department of Molecular and Clinical Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Henry N Ginsberg
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Marcello Arca
- Department of Internal Medicine and Allied Sciences, Center for Rare Disorders of Lipid Metabolism, Sapienza University of Rome, Rome, Italy
| | - Maurizio Averna
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialities, University of Palermo, Palermo, Italy
| | - Christoph J Binder
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Laura Calabresi
- Centro Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - M John Chapman
- National Institute for Health and Medical Research (INSERM), Sorbonne University and Pitié-Salpétrière University Hospital, Paris, France
| | - Marina Cuchel
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Ruth Frikke-Schmidt
- Department of Clinical Medicine, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Biochemistry, Rigshospitalet Copenhagen University Hospital, Copenhagen, Denmark
| | - Daniel Gaudet
- Clinical Lipidology and Rare Lipid Disorders Unit, Community Genomic Medicine Center, Department of Medicine, Université de Montréal, Montreal, QC, Canada; ECOGENE, Clinical and Translational Research Center, Chicoutimi, QC, Canada; Lipid Clinic, Chicoutimi Hospital, Chicoutimi, QC, Canada
| | - G Kees Hovingh
- Department of Vascular Medicine, Academic Medical Center, Amsterdam, Netherlands
| | - Florian Kronenberg
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Dieter Lütjohann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Klaus G Parhofer
- Medizinische Klinik IV-Grosshadern, University of Munich, Munich, Germany
| | - Frederick J Raal
- Carbohydrate and Lipid Metabolism Research Unit, Division of Endocrinology and Metabolism, Department of Medicine, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Johannesburg, South Africa
| | - Kausik K Ray
- Imperial Centre for Cardiovascular Disease Prevention, Department of Primary Care and Public Health, Imperial College London, London, UK
| | - Alan T Remaley
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jane K Stock
- European Atherosclerosis Society, Gothenburg, Sweden
| | - Erik S Stroes
- Department of Vascular Medicine, Academic Medical Center, Amsterdam, Netherlands
| | - Lale Tokgözoğlu
- Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Alberico L Catapano
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy; IRCCS MultiMedica, Milan, Italy
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Abstract
Both low and very high levels of high-density lipoprotein cholesterol (HDL-C) increase the risk of atherosclerotic cardiovascular disease (ASCVD) and shorten life expectancy. Low and high levels of HDL‑C are often caused by underlying diseases, lifestyle or medication, which should primarily be excluded. Much less frequently, monogenic diseases due to mutations in the APOA1, ABCA1 and LCAT genes are the cause of very low or unmeasurable HDL‑C levels or in the CETP, LIPC and SCARB1 genes for very high HDL‑C values. Genetic and detailed biochemical diagnostics should be considered, especially in cases of absolute HDL deficiency, early onset ASCVD or the presence of clinical symptoms or laboratory values characteristic for deficiencies of apolipoprotein A‑I (ApoA-I), lecithin cholesterol acyltransferase (LCAT) or Tangier disease. These included corneal opacities, xanthomas, large tonsils, hepatomegaly, peripheral neuropathy, proteinuria, anemia or thrombocytopenia. Sequencing of the APOA1 gene should also be considered in familial amyloidosis. There is no specific treatment for monogenic HDL diseases. Cholesterol and blood pressure lowering are indicated for the prevention of cardiovascular and renal complications.
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Affiliation(s)
- Arnold von Eckardstein
- Institut für Klinische Chemie, Universitätsspital Zürich und Universität Zürich, Rämistrasse 100, 8091, Zürich, Schweiz.
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High-density lipoprotein metabolism and reverse cholesterol transport: strategies for raising HDL cholesterol. Anatol J Cardiol 2019; 18:149-154. [PMID: 28766509 PMCID: PMC5731265 DOI: 10.14744/anatoljcardiol.2017.7608] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A key to effective treatment of cardiovascular disease is to understand the body’s complex lipoprotein transport system. Reverse cholesterol transport (RCT) is the process of cholesterol movement from the extrahepatic tissues back to the liver. Lipoproteins containing apoA-I [high-density lipoprotein (HDL)] are key mediators in RCT, whereas non-high-density lipoproteins (non-HDL, lipoproteins containing apoB) are involved in the lipid delivery pathway. HDL particles are heterogeneous; they differ in proportion of proteins and lipids, size, shape, and charge. HDL heterogeneity is the result of the activity of several factors that assemble and remodel HDL particles in plasma: ATP-binding cassette transporter A1 (ABCA1), lecithin cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP), hepatic lipase (HL), phospholipid transfer protein (PLTP), endothelial lipase (EL), and scavenger receptor class B type I (SR-BI). The RCT pathway consists of the following steps: 1. Cholesterol efflux from peripheral tissues to plasma, 2. LCAT-mediated esterification of cholesterol and remodeling of HDL particles, 3. direct pathway of HDL cholesterol delivery to the liver, and 4. indirect pathway of HDL cholesterol delivery to the liver via CETP-mediated transfer There are several established strategies for raising HDL cholesterol in humans, such as lifestyle changes; use of drugs including fibrates, statins, and niacin; and new therapeutic approaches. The therapeutic approaches include CETP inhibition, peroxisome proliferator-activated receptor (PPAR) agonists, synthetic farnesoid X receptor agonists, and gene therapy. Results of clinical trials should be awaited before further clinical management of atherosclerotic cardiovascular disease.
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Update on the diagnosis, treatment and management of rare genetic lipid disorders. Pathology 2019; 51:193-201. [DOI: 10.1016/j.pathol.2018.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 11/06/2018] [Accepted: 11/06/2018] [Indexed: 02/03/2023]
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Nakajima K, Machida T, Imamura S, Kawase D, Miyashita K, Fukamachi I, Maeda M, Muraba Y, Koga T, Kobayashi J, Kimura T, Nakajima K, Murakami M. An automated method for measuring lipoprotein lipase and hepatic triglyceride lipase activities in post-heparin plasma. Clin Chim Acta 2018; 487:54-59. [PMID: 30218657 DOI: 10.1016/j.cca.2018.09.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 09/08/2018] [Accepted: 09/11/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) play a central role in triglyceride-rich lipoprotein metabolism by catalyzing the hydrolysis of triglycerides. Quantification of LPL and HTGL activity is useful for diagnosing lipid disorders, but there has been no automated method for measuring these lipase activities. METHODS The automated kinetic colorimetric method was used for assaying LPL and HTGL activity in the post-heparin plasma using the natural long-chain fatty acid 2-diglyceride as a substrate. LPL activity was determined with apoCII and HTGL activity was determined without apoCII with 2 channel of auto-analyzer. RESULTS The calibration curve for dilution tests of the LPL and HTGL activity assay ranged from 0.0 to 500 U/L. Within-run CV was obtained within a range of 5%. No interference was observed in the testing of specimens containing potentially interfering substances. The measurement range of LPL activity in the post-heparin plasma was 30-153 U/L, while HTGL activity was 135-431 U/L in normal controls. CONCLUSIONS The L PL and HTGL activity assays are applicable to quantitating the LPL and HTGL activity in the post-heparin plasma. This assay is more convenient and faster than radiochemical assay and highly suitable for the detection of lipid disorders.
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Affiliation(s)
- Kiyomi Nakajima
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Tetsuo Machida
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | | | | | | | | | | | | | | | - Junji Kobayashi
- Department of General Internal Medicine, Kanazawa Medical University, Kanazawa, Japan
| | - Takao Kimura
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Katsuyuki Nakajima
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan; Hidaka Hospital, Takasaki, Gunma, Japan; Department of General Internal Medicine, Kanazawa Medical University, Kanazawa, Japan.
| | - Masami Murakami
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
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Dron JS, Wang J, Low-Kam C, Khetarpal SA, Robinson JF, McIntyre AD, Ban MR, Cao H, Rhainds D, Dubé MP, Rader DJ, Lettre G, Tardif JC, Hegele RA. Polygenic determinants in extremes of high-density lipoprotein cholesterol. J Lipid Res 2017; 58:2162-2170. [PMID: 28870971 PMCID: PMC5665671 DOI: 10.1194/jlr.m079822] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 08/31/2017] [Indexed: 11/24/2022] Open
Abstract
HDL cholesterol (HDL-C) remains a superior biochemical predictor of CVD risk, but its genetic basis is incompletely defined. In patients with extreme HDL-C concentrations, we concurrently evaluated the contributions of multiple large- and small-effect genetic variants. In a discovery cohort of 255 unrelated lipid clinic patients with extreme HDL-C levels, we used a targeted next-generation sequencing panel to evaluate rare variants in known HDL metabolism genes, simultaneously with common variants bundled into a polygenic trait score. Two additional cohorts were used for validation and included 1,746 individuals from the Montréal Heart Institute Biobank and 1,048 individuals from the University of Pennsylvania. Findings were consistent between cohorts: we found rare heterozygous large-effect variants in 18.7% and 10.9% of low- and high-HDL-C patients, respectively. We also found common variant accumulation, indicated by extreme polygenic trait scores, in an additional 12.8% and 19.3% of overall cases of low- and high-HDL-C extremes, respectively. Thus, the genetic basis of extreme HDL-C concentrations encountered clinically is frequently polygenic, with contributions from both rare large-effect and common small-effect variants. Multiple types of genetic variants should be considered as contributing factors in patients with extreme dyslipidemia.
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Affiliation(s)
- Jacqueline S Dron
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Jian Wang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Cécile Low-Kam
- Montréal Heart Institute et Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Sumeet A Khetarpal
- Departments of Genetics and Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - John F Robinson
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Adam D McIntyre
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Matthew R Ban
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Henian Cao
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - David Rhainds
- Montréal Heart Institute et Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Marie-Pierre Dubé
- Montréal Heart Institute et Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Daniel J Rader
- Departments of Genetics, Medicine, and Pediatrics, the Cardiovascular Institute, and the Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Guillaume Lettre
- Montréal Heart Institute et Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Jean-Claude Tardif
- Montréal Heart Institute et Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Robert A Hegele
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
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Buonuomo PS, Rabacchi C, Macchiaiolo M, Trenti C, Fasano T, Tarugi P, Bartuli A, Bertolini S, Calandra S. Incidental finding of severe hypertriglyceridemia in children. Role of multiple rare variants in genes affecting plasma triglyceride. J Clin Lipidol 2017; 11:1329-1337.e3. [PMID: 28951076 DOI: 10.1016/j.jacl.2017.08.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/18/2017] [Accepted: 08/25/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND The incidental finding of severe hypertriglyceridemia (HyperTG) in a child may suggest the diagnosis of familial chylomicronemia syndrome (FCS), a recessive disorder of the intravascular hydrolysis of triglyceride (TG)-rich lipoproteins. FCS may be due to pathogenic variants in lipoprotein lipase (LPL), as well as in other proteins, such as apolipoprotein C-II and apolipoprotein A-V (activators of LPL), GPIHBP1 (the molecular platform required for LPL activity on endothelial surface) and LMF1 (a factor required for intracellular formation of active LPL). OBJECTIVE Molecular characterization of 5 subjects in whom HyperTG was an incidental finding during infancy/childhood. METHODS We performed the parallel sequencing of 20 plasma TG-related genes. RESULTS Three children with severe HyperTG were found to be compound heterozygous for rare pathogenic LPL variants (2 nonsense, 3 missense, and 1 splicing variant). Another child was found to be homozygous for a nonsense variant of APOA5, which was also found in homozygous state in his father with longstanding HyperTG. The fifth patient with a less severe HyperTG was found to be heterozygous for a frameshift variant in LIPC resulting in a truncated Hepatic Lipase. In addition, 1 of the patients with LPL deficiency and the patient with APOA-V deficiency were also heterozygous carriers of a pathogenic variant in LIPC and LPL gene, respectively, whereas the patient with LIPC variant was also a carrier of a rare APOB missense variant. CONCLUSIONS Targeted parallel sequencing of TG-related genes is recommended to define the molecular defect in children presenting with an incidental finding of HyperTG.
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Affiliation(s)
| | - Claudio Rabacchi
- Department of Life Sciences, University of Modena & Reggio Emilia, Modena, Italy
| | - Marina Macchiaiolo
- Rare Diseases and Medical Genetics, Bambino Gesù Children Hospital, Rome, Italy
| | - Chiara Trenti
- Department of Internal Medicine, Lipid Clinic, IRCCS-Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Tommaso Fasano
- Clinical Chemistry and Endocrinology Laboratory, IRCCS-Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Patrizia Tarugi
- Department of Life Sciences, University of Modena & Reggio Emilia, Modena, Italy
| | - Andrea Bartuli
- Rare Diseases and Medical Genetics, Bambino Gesù Children Hospital, Rome, Italy
| | - Stefano Bertolini
- Department of Internal Medicine, University of Genova, Genova, Italy.
| | - Sebastiano Calandra
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena & Reggio Emilia, Modena, Italy.
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Miyashita K, Nakajima K, Fukamachi I, Muraba Y, Koga T, Shimomura Y, Machida T, Murakami M, Kobayashi J. A new enzyme-linked immunosorbent assay system for human serum hepatic triglyceride lipase. J Lipid Res 2017. [PMID: 28634192 DOI: 10.1194/jlr.m075432] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There is no established method for measuring human hepatic triglyceride (TG) lipase (HTGL) concentration in serum. In this study, we developed new monoclonal Abs (MoAbs) (9A1 mouse MoAb and 141A1 rat MoAb) that react with HTGL both in serum and in postheparin plasma (PHP) and established a novel ELISA system for measuring serum HTGL and PHP-HTGL concentrations. To confirm the specificity of MoAbs, we performed immunoprecipitation-immunoblotting analysis. Both 9A1 mouse MoAb and 141A1 rat MoAb were able to immunoprecipitate not only recombinant HTGL and PHP-HTGL but also serum HTGL, demonstrating that HTGL exists in serum obtained without heparin injection. This method yielded intra- and interassay coefficients of variation of <6% and showed no cross-reactivity with LPL or endothelial lipase. In clinical analysis on 42 male subjects with coronary artery disease, there were strong positive correlations of serum HTGL concentration to PHP-HTGL concentration (r = 0.727, P < 0.01). Serum HTGL concentrations showed positive correlations to serum TGs (r = 0.314, P < 0.05) and alanine aminotransferase (r = 0.406, P < 0.01), and tendencies toward positive correlations to LDL cholesterol, small dense LDL, and γGTP. These results suggest that this new ELISA method for measuring serum HTGL is applicable in daily clinical practice.
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Affiliation(s)
| | - Katsuyuki Nakajima
- Department of General Medicine, Kanazawa Medical University, Ishikawa, Japan; Hidaka Hospital, Takasaki, Japan
| | - Isamu Fukamachi
- Immuno-Biological Laboratories Co., Ltd., Fujioka, Gunma, Japan
| | | | | | | | - Tetsuyo Machida
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Masami Murakami
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Junji Kobayashi
- Department of General Medicine, Kanazawa Medical University, Ishikawa, Japan.
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20
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Tani M, Horvath KV, Lamarche B, Couture P, Burnett JR, Schaefer EJ, Asztalos BF. High-density lipoprotein subpopulation profiles in lipoprotein lipase and hepatic lipase deficiency. Atherosclerosis 2016; 253:7-14. [PMID: 27573733 DOI: 10.1016/j.atherosclerosis.2016.08.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 08/01/2016] [Accepted: 08/18/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS Our aim was to gain insight into the role that lipoprotein lipase (LPL) and hepatic lipase (HL) plays in HDL metabolism and to better understand LPL- and HL-deficiency states. METHODS We examined the apolipoprotein (apo) A-I-, A-II-, A-IV-, C-I-, C-III-, and E-containing HDL subpopulation profiles, assessed by native 2-dimensional gel-electrophoresis and immunoblotting, in 6 homozygous and 11 heterozygous LPL-deficient, 6 homozygous and 4 heterozygous HL-deficient, and 50 control subjects. RESULTS LPL-deficient homozygotes had marked hypertriglyceridemia and significant decreases in LDL-C, HDL-C, and apoA-I. Their apoA-I-containing HDL subpopulation profile was shifted toward small HDL particles compared to controls. HL-deficient homozygotes had moderate hypertriglyceridemia, modest increases in LDL-C and HDL-C level, but normal apoA-I concentration. HL-deficient homozygotes had a unique distribution of apoA-I-containing HDL particles. The normally apoA-I:A-II, intermediate-size (α-2 and α-3) particles were significantly decreased, while the normally apoA-I only (very large α-1, small α-4, and very small preβ-1) particles were significantly elevated. In contrast to control subjects, the very large α-1 particles of HL-deficient homozygotes were enriched in apoA-II. Homozygous LPL- and HL-deficient subjects also had abnormal distributions of apo C-I, C-III, and E in HDL particles. Values for all measured parameters in LPL- and HL-deficient heterozygotes were closer to values measured in controls than in homozygotes. CONCLUSIONS Our data are consistent with the concept that LPL is important for the maturation of small discoidal HDL particles into large spherical HDL particles, while HL is important for HDL remodeling of very large HDL particles into intermediate-size HDL particles.
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Affiliation(s)
- Mariko Tani
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Katalin V Horvath
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Benoit Lamarche
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec, Canada
| | - Patrick Couture
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec, Canada
| | - John R Burnett
- Department of Clinical Biochemistry, Path West Laboratory Medicine, Royal Perth and Fiona Stanley Hospital Network and School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
| | - Ernst J Schaefer
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Bela F Asztalos
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
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Trigatti BL, Hegele RA. Rare Genetic Variants and High-Density Lipoprotein. Arterioscler Thromb Vasc Biol 2016; 36:e53-5. [DOI: 10.1161/atvbaha.116.307688] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Bernardo L. Trigatti
- From the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada (B.L.T.); Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada (B.L.T.); and Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada (R.A.H.)
| | - Robert A. Hegele
- From the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada (B.L.T.); Thrombosis and Atherosclerosis Research Institute, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada (B.L.T.); and Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada (R.A.H.)
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Kobayashi J, Miyashita K, Nakajima K, Mabuchi H. Hepatic Lipase: a Comprehensive View of its Role on Plasma Lipid and Lipoprotein Metabolism. J Atheroscler Thromb 2015. [PMID: 26194979 DOI: 10.5551/jat.31617] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Hepatic lipase (HL) is a key enzyme catalyzing the hydrolysis of triglycerides (TG) and phospholipids (PLs) in several lipoproteins. It is generally recognized that HL is involved in the remodeling of remnant, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and the production of small, dense low-density lipoproteins (sd-LDLs).On the other hand, it is unclear whether HL accelerates or retards atherosclerosis. From the clinical point of view, HL deficiency may provide useful information on answering this question, but the rarity of this disease makes it impossible to conduct epidemiological study.In this review, we describe a comprehensive and updated view of the clinical significance of HL on lipid and lipoprotein metabolism.
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Hopkins PN, Brinton EA, Nanjee MN. Hyperlipoproteinemia type 3: the forgotten phenotype. Curr Atheroscler Rep 2015; 16:440. [PMID: 25079293 DOI: 10.1007/s11883-014-0440-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Hyperlipoproteinemia type 3 (HLP3) is caused by impaired removal of triglyceride-rich lipoproteins (TGRL) leading to accumulation of TGRL remnants with abnormal composition. High levels of these remnants, called β-VLDL, promote lipid deposition in tuberous xanthomas, atherosclerosis, premature coronary artery disease, and early myocardial infarction. Recent genetic and molecular studies suggest more genes than previously appreciated may contribute to the expression of HLP3, both through impaired hepatic TGRL processing or removal and increased TGRL production. HLP3 is often highly amenable to appropriate treatment. Nevertheless, most HLP3 probably goes undiagnosed, in part because of lack of awareness of the relatively high prevalence (about 0.2% in women and 0.4-0.5% in men older than 20 years) and largely because of infrequent use of definitive diagnostic methods.
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Affiliation(s)
- Paul N Hopkins
- Cardiovascular Genetics, Department of Internal Medicine, University of Utah, 420 Chipeta Way, Room 1160, Salt Lake City, UT, 84108, USA,
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24
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Brunham LR, Hayden MR. Human genetics of HDL: Insight into particle metabolism and function. Prog Lipid Res 2015; 58:14-25. [DOI: 10.1016/j.plipres.2015.01.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/22/2014] [Accepted: 01/07/2015] [Indexed: 10/24/2022]
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25
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Kwiterovich PO. Detection and Treatment of Children and Adolescents with Dyslipidemia. DYSLIPIDEMIAS 2015. [DOI: 10.1007/978-1-60761-424-1_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Bamji-Mirza M, Zhang W, Yao Z. Expression of human hepatic lipase negatively impacts apolipoprotein A-I production in primary hepatocytes from Lipc-null mice. J Biomed Res 2014; 28:201-12. [PMID: 25013403 PMCID: PMC4085557 DOI: 10.7555/jbr.28.20130184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 12/28/2013] [Accepted: 02/22/2014] [Indexed: 11/22/2022] Open
Abstract
This study aimed to examine whether expression of human hepatic lipase (hHL) exerted an intracellular effect on hepatic production of apolipoprotein (apo) A-I. The levels of secreted and cell-associated apoA-I were contrasted between primary hepatocytes isolated from Lipc-null and C57BL/6 mice, and between Lipc-null hepatocytes transfected with either hHL-encoding or control adenovirus. An HSPG-binding deficient hHL protein (hHLmt) was used to determine the impact of cell surface binding on HL action. Accumulation of apoA-I in conditioned media of primary hepatocytes isolated from Lipc-null mice was increased as compared to that from C57BL/6 mice. Metabolic labeling experiments showed that secretion of 35S-apoA-I from Lipc-null cells was significantly higher than that from C57BL/6 cells. Expression of hHL in Lipc-null hepatocytes, through adenovirus-mediated gene transfer, resulted in decreased synthesis and secretion of 35S-apoA-I, but not 35S-apoE, as compared with cells transfected with control adenovirus. Expression of HSPG-binding deficient hHLmt in Lipc-null cells also exerted an inhibitory effect on apoA-I production, even though hHLmt displayed impaired exit from the endoplasmic reticulum as compared with hHL. Subcellular fractionation revealed that expression of hHL or hHLmt led to increased microsome-association of apoA-I relative to non-transfected control. Expression of hHL negatively impacts hepatic production of apoA-I.
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Affiliation(s)
- Michelle Bamji-Mirza
- Department of Biochemistry, Microbiology & Immunology, and ; Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5, Canada; ; Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, Ontario, K1A 0R6, Canada
| | - Wandong Zhang
- Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5, Canada; ; Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, Ontario, K1A 0R6, Canada
| | - Zemin Yao
- Department of Biochemistry, Microbiology & Immunology, and ; Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, K1H 8M5, Canada
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Yang Y, Kuwano T, Lagor WR, Albert CJ, Brenton S, Rader DJ, Ford DA, Brown RJ. Lipidomic analyses of female mice lacking hepatic lipase and endothelial lipase indicate selective modulation of plasma lipid species. Lipids 2014; 49:505-15. [PMID: 24777581 DOI: 10.1007/s11745-014-3907-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 04/08/2014] [Indexed: 11/26/2022]
Abstract
Hepatic lipase (HL) and endothelial lipase (EL) share overlapping and complementary roles in lipoprotein metabolism. The deletion of HL and EL alleles in mice raises plasma total cholesterol and phospholipid concentrations. However, the influence of HL and EL in vivo on individual molecular species from each class of lipid is not known. We hypothesized that the loss of HL, EL, or both in vivo may affect select molecular species from each class of lipids. To test this hypothesis, we performed lipidomic analyses on plasma and livers from fasted female wild-type, HL-knockout, EL-knockout, and HL/EL-double knockout mice. Overall, the loss of HL, EL, or both resulted in minimal changes to hepatic lipids; however, select species of CE were surprisingly reduced in the livers of mice only lacking EL. The loss of HL, EL, or both reduced the plasma concentrations for select molecular species of triacylglycerol, diacylglycerol, and free fatty acid. On the other hand, the loss of HL, EL, or both raised the plasma concentrations for select molecular species of phosphatidylcholine, cholesteryl ester, diacylglycerol, sphingomyelin, ceramide, plasmanylcholine, and plasmenylcholine. The increased plasma concentration of select ether phospholipids was evident in the absence of EL, thus suggesting that EL might exhibit a phospholipase A2 activity. Using recombinant EL, we showed that it could hydrolyse the artificial phospholipase A2 substrate 4-nitro-3-(octanoyloxy)benzoic acid. In summary, our study shows for the first time the influence of HL and EL on individual molecular species of several classes of lipids in vivo using lipidomic methods.
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Affiliation(s)
- Yanbo Yang
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
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Miyashita K, Kobayashi J, Imamura S, Kinoshita N, Stanhope KL, Havel PJ, Nakajima K, Machida T, Sumino H, Nara M, Murakami M. A new enzyme-linked immunosorbent assay system for human hepatic triglyceride lipase. Clin Chim Acta 2013; 424:201-6. [DOI: 10.1016/j.cca.2013.06.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 06/12/2013] [Accepted: 06/13/2013] [Indexed: 11/29/2022]
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Wang Z, Li S, Sun L, Fan J, Liu Z. Comparative analyses of lipoprotein lipase, hepatic lipase, and endothelial lipase, and their binding properties with known inhibitors. PLoS One 2013; 8:e72146. [PMID: 23991054 PMCID: PMC3749185 DOI: 10.1371/journal.pone.0072146] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Accepted: 07/08/2013] [Indexed: 11/30/2022] Open
Abstract
The triglyceride lipase gene subfamily plays a central role in lipid and lipoprotein metabolism. There are three members of this subfamily: lipoprotein lipase, hepatic lipase, and endothelial lipase. Although these lipases are implicated in the pathophysiology of hyperlipidemia and atherosclerosis, their structures have not been fully solved. In the current study, we established homology models of these three lipases, and carried out analysis of their activity sites. In addition, we investigated the kinetic characteristics for the catalytic residues using a molecular dynamics simulation strategy. To elucidate the molecular interactions and determine potential key residues involved in the binding to lipase inhibitors, we analyzed the binding pockets and binding poses of known inhibitors of the three lipases. We identified the spatial consensus catalytic triad “Ser-Asp-His”, a characteristic motif in all three lipases. Furthermore, we found that the spatial characteristics of the binding pockets of the lipase molecules play a key role in ligand recognition, binding poses, and affinities. To the best of our knowledge, this is the first report that systematically builds homology models of all the triglyceride lipase gene subfamily members. Our data provide novel insights into the molecular structures of lipases and their structure-function relationship, and thus provides groundwork for functional probe design towards lipase-based therapeutic inhibitors for the treatment of hyperlipidemia and atherosclerosis.
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Affiliation(s)
- Ziyun Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, P. R. China
| | - Shen Li
- Department of Molecular Pathology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Lidan Sun
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, P. R. China
| | - Jianglin Fan
- Department of Molecular Pathology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
- * E-mail: (ZML); (JLF)
| | - Zhenming Liu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, P. R. China
- * E-mail: (ZML); (JLF)
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Fu J, Kwok S, Sinai L, Abdel-Razek O, Babula J, Chen D, Farago E, Fernandopulle N, Leith S, Loyzer M, Lu C, Malkani N, Morris N, Schmidt M, Stringer R, Whitehead H, Ban MR, Dubé JB, McIntyre A, Johansen CT, Cao H, Wang J, Hegele RA. Western Database of Lipid Variants (WDLV): A Catalogue of Genetic Variants in Monogenic Dyslipidemias. Can J Cardiol 2013; 29:934-9. [DOI: 10.1016/j.cjca.2013.01.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 01/16/2013] [Accepted: 01/16/2013] [Indexed: 01/25/2023] Open
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Endoplasmic reticulum-localized hepatic lipase decreases triacylglycerol storage and VLDL secretion. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1113-23. [DOI: 10.1016/j.bbalip.2013.01.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Revised: 01/09/2013] [Accepted: 01/23/2013] [Indexed: 01/07/2023]
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Abstract
The HDL hypothesis has suffered damage in the past few years. Clinical trials have shown that raising HDL cholesterol levels does not improve cardiovascular disease (CVD) outcomes. In addition, Mendelian randomization studies have shown that DNA variants that alter HDL cholesterol levels in populations are unrelated to incident CVD events. Balancing this deluge of negative data are substantial basic science data supporting the concept that raising HDL cholesterol levels reduces CVD risk. Also, functionally relevant HDL subfractions might be more important determinants of risk than overall HDL cholesterol levels. But, while wobbly, the HDL hypothesis is still standing, seemingly too big to fail owing to past intellectual, economic and psychological investments in the idea.
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Affiliation(s)
- Dominic S Ng
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael's Hospital, Shuter Wing, Room 3-041, 30 Bond Street, Toronto, ON M5B 1W8, Canada
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Abstract
All organisms use fatty acids (FAs) for energy substrates and as precursors for membrane and signaling lipids. The most efficient way to transport and store FAs is in the form of triglycerides (TGs); however, TGs are not capable of traversing biological membranes and therefore need to be cleaved by TG hydrolases ("lipases") before moving in or out of cells. This biochemical process is generally called "lipolysis." Intravascular lipolysis degrades lipoprotein-associated TGs to FAs for their subsequent uptake by parenchymal cells, whereas intracellular lipolysis generates FAs and glycerol for their release (in the case of white adipose tissue) or use by cells (in the case of other tissues). Although the importance of lipolysis has been recognized for decades, many of the key proteins involved in lipolysis have been uncovered only recently. Important new developments include the discovery of glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), the molecule that moves lipoprotein lipase from the interstitial spaces to the capillary lumen, and the discovery of adipose triglyceride lipase (ATGL) and comparative gene identification-58 (CGI-58) as crucial molecules in the hydrolysis of TGs within cells. This review summarizes current views of lipolysis and highlights the relevance of this process to human disease.
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Affiliation(s)
- Stephen G. Young
- Department of Medicine
- Department of Human Genetics, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
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New Research Advances in Genetics Associated With High-density Lipoprotein Cholesterol*. PROG BIOCHEM BIOPHYS 2013. [DOI: 10.3724/sp.j.1206.2012.00140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Farahani P, Fisler JS, Wong H, Diament AL, Yi N, Warden CH. Reciprocal Hemizygosity Analysis of Mouse Hepatic Lipase Reveals Influence on Obesity. ACTA ACUST UNITED AC 2012; 12:292-305. [PMID: 14981222 DOI: 10.1038/oby.2004.37] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVES We previously demonstrated coincident quantitative trait loci (QTLs) for percentage body fat, plasma hepatic lipase (HL) activity, and plasma cholesterol on mouse chromosome 7. In the present study, we investigated whether hepatic lipase (Lipc) is an obesity gene, whether Lipc interacts with an unknown gene on chromosome 7, and how HL activity is linked to the chromosome 7 locus. RESEARCH METHODS AND PROCEDURES BSB mice are a model of complex obesity due to interactions among genes from C57BL/6J and Mus spretus (SPRET) in (C57BL/6J x SPRET) x C57BL/6J backcross mice. Five crosses tested the impact on obesity of combinations of inactive (knockout) and wild-type Lipc alleles from C57BL/6J or SPRET in a reciprocal hemizygosity analysis. RESULTS The combined data from this allelic series suggest that Lipc alleles, and not alleles from a gene linked to Lipc, influence obesity. No interaction between Lipc and chromosome 7 was demonstrated. We confirmed the chromosome 7 QTLs for obesity, HL activity, and cholesterol. Because obesity and HL activity are not consistently associated in the BSB model, linkage of HL activity to chromosome 7 is not secondary to obesity per se. We also report, for the first time to our knowledge, a QTL in mammals for food intake. DISCUSSION This use of reciprocal hemizygosity analysis in mammals, which, to our knowledge, is the first reported, reveals its power to detect previously unknown effects of Lipc on obesity.
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Affiliation(s)
- Poupak Farahani
- Rowe Program in Genetics, University of California, Davis, California 95616, USA
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Rosenson RS, Brewer HB, Davidson WS, Fayad ZA, Fuster V, Goldstein J, Hellerstein M, Jiang XC, Phillips MC, Rader DJ, Remaley AT, Rothblat GH, Tall AR, Yvan-Charvet L. Cholesterol efflux and atheroprotection: advancing the concept of reverse cholesterol transport. Circulation 2012; 125:1905-19. [PMID: 22508840 PMCID: PMC4159082 DOI: 10.1161/circulationaha.111.066589] [Citation(s) in RCA: 692] [Impact Index Per Article: 57.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Robert S Rosenson
- Mount Sinai Heart, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1030, New York, NY 10029, USA.
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Pulchinelli A, Costa AMM, de Carvalho CV, de Souza NCN, Haidar MA, Andriolo A, da Silva IDCG. Positive association of the hepatic lipase gene polymorphism c.514C > T with estrogen replacement therapy response. Lipids Health Dis 2011; 10:197. [PMID: 22047520 PMCID: PMC3225335 DOI: 10.1186/1476-511x-10-197] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 11/02/2011] [Indexed: 11/20/2022] Open
Abstract
Background Hepatic lipase (HL), an enzyme present in the hepatic sinusoids, is responsible for the lipolysis of lipoproteins. Human HL contains four polymorphic sites: G-250A, T-710C, A-763G, and C-514T single-nucleotide polymorphism (SNPs). The last polymorphism is the focus of the current study. The genotypes associated with the C-514T polymorphism are CC (normal homozygous - W), CT (heterozygous - H), and TT (minor-allele homozygous - M). HL activity is significantly impaired in individuals of the TT and CT genotypes. A total of 58 post-menopausal women were studied. The subjects were hysterectomized women receiving hormone replacement therapy consisting of 0.625 mg of conjugated equine estrogen once a day. The inclusion criteria were menopause of up to three years and normal blood tests, radiographs, cervical-vaginal cytology, and densitometry. DNA was extracted from the buccal and blood cells of all 58 patients using a commercially available kit (GFX® - Amersham-Pharmacia, USA). Results Statistically significant reductions in triglycerides (t = 2.16; n = 58; p = 0.03) but not in total cholesterol (t = 0.14; n = 58; p = 0.89) were found after treatment. This group of good responders were carriers of the T allele; the CT and TT genotypes were present significantly more frequently than in the group of non-responders (p = 0.02 or p = 0.07, respectively). However, no significant difference in HDL-C (t = 0.94; n = 58; p = 0.35) or LDL-C (t = -0.83; n = 58; p = 0.41) was found in these patients. Conclusions The variation in lipid profile associated with the C-514T polymorphism is significant, and the T allele is associated with the best response to ERT.
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Affiliation(s)
- Alvaro Pulchinelli
- Laboratório de Biologia Molecular, Departamento de Ginecologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
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Péterfy M. Lipase maturation factor 1: a lipase chaperone involved in lipid metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:790-4. [PMID: 22063272 DOI: 10.1016/j.bbalip.2011.10.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 10/16/2022]
Abstract
Mutations in lipase maturation factor 1 (LMF1) are associated with severe hypertriglyceridemia in mice and human subjects. The underlying cause is impaired lipid clearance due to lipase deficiency. LMF1 is a chaperone of the endoplasmic reticulum (ER) and it is critically required for the post-translational activation of three vascular lipases: lipoprotein lipase (LPL), hepatic lipase (HL) and endothelial lipase (EL). As LMF1 is only required for the maturation of homodimeric, but not monomeric, lipases, it is likely involved in the assembly of inactive lipase subunits into active enzymes and/or the stabilization of active dimers. Herein, we provide an overview of current understanding of LMF1 function and propose that it may play a regulatory role in lipase activation and lipid metabolism. Further studies will be required to test this hypothesis and elucidate the full spectrum of phenotypes in combined lipase deficiency. This article is part of a Special Issue entitled Triglyceride Metabolism and Disease.
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Affiliation(s)
- Miklós Péterfy
- Medical Genetics Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States.
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Role of hepatic lipase and endothelial lipase in high-density lipoprotein-mediated reverse cholesterol transport. Curr Atheroscler Rep 2011; 13:257-65. [PMID: 21424685 PMCID: PMC3085744 DOI: 10.1007/s11883-011-0175-2] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reverse cholesterol transport (RCT) constitutes a key part of the atheroprotective properties of high-density lipoproteins (HDL). Hepatic lipase (HL) and endothelial lipase (EL) are negative regulators of plasma HDL cholesterol levels. Although overexpression of EL decreases overall macrophage-to-feces RCT, knockout of both HL and EL leaves RCT essentially unaffected. With respect to important individual steps of RCT, current data on the role of EL and HL in cholesterol efflux are not conclusive. Both enzymes increase hepatic selective cholesterol uptake; however, this does not translate into altered biliary cholesterol secretion, which is regarded the final step of RCT. Also, the impact of HL and EL on atherosclerosis is not clear cut; rather it depends on respective experimental conditions and chosen models. More mechanistic insights into the diverse biological properties of these enzymes are therefore required to firmly establish EL and HL as targets for the treatment of atherosclerotic cardiovascular disease.
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Nishimura M, Yamamoto H, Yoshida T, Seimiya M, Sawabe Y, Matsushita K, Umemura H, Sogawa K, Takizawa H, Yokosuka O, Nomura F. Decreases in the serum VLDL-TG/non-VLDL-TG ratio from early stages of chronic hepatitis C: alterations in TG-rich lipoprotein levels. PLoS One 2011; 6:e17309. [PMID: 21364889 PMCID: PMC3045437 DOI: 10.1371/journal.pone.0017309] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 01/28/2011] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The liver secretes very-low-density lipoproteins (VLDLs) and plays a key role in lipid metabolism. Plasma total triglyceride (TG) level variations have been studied in patients with hepatitis C virus (HCV)-related chronic hepatitis (CH-C). However, the results of these studies are variable. A homogenous assay protocol was recently proposed to directly measure the TG content in VLDL (VLDL-TG) and VLDL remnants. METHODOLOGY/PRINCIPAL FINDINGS Using the assay protocol, we determined serum VLDL-TG levels in 69 fasting patients with biopsy-proven HCV-related chronic liver disease and 50 healthy subjects. Patients were classified into stages F0-F4 using the 5-point Desmet scale. Serum total TG levels in patients with non-cirrhotic (F1-F3) CH-C did not demonstrate significant differences compared with healthy subjects, but serum VLDL-TG levels did demonstrate significant differences. Mean serum VLDL-TG levels tended to decrease with disease progression from F1 to F4 (cirrhosis). Compared with healthy subjects, serum non-VLDL-TG levels significantly increased in patients with stages F2 and F3 CH-C; however, we observed no significant difference in patients with liver cirrhosis. Furthermore, the serum VLDL-TG/non-VLDL-TG ratio, when taken, demonstrated a significant decrease in patients with CH-C from the mildest stage F1 onward. CONCLUSIONS/SIGNIFICANCE The decrease in serum VLDL-TG levels was attenuated by increase in non-VLDL-TG levels in patients with non-cirrhotic CH-C, resulting in comparable total TG levels. Results of previous studies though variable, were confirmed to have a logical basis. The decrease in the serum VLDL-TG/non-VLDL-TG ratio as early as stage F1 demonstrated TG metabolic alterations in early stages of CH-C for the first time. The involvement of TG metabolism in CH-C pathogenesis has been established in experimental animals, while conventional TG measurements are generally considered as poor indicators of CH-C progression in clinical practice. The serum VLDL-TG/non-VLDL-TG ratio, which focuses on TG metabolic alterations, may be an early indicator of CH-C.
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Affiliation(s)
- Motoi Nishimura
- Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University, Chiba City, Japan.
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Bamji-Mirza M, Sundaram M, Zhong S, Yao EF, Parks RJ, Yao Z. Secretion of triacylglycerol-poor VLDL particles from McA-RH7777 cells expressing human hepatic lipase. J Lipid Res 2010; 52:540-8. [PMID: 21189265 DOI: 10.1194/jlr.m012476] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatic lipase (HL) plays a role in the catabolism of apolipoprotein (apo)B-containing lipoproteins through its lipolytic and ligand-binding properties. We describe a potential intracellular role of HL in the assembly and secretion of VLDL. Transient or stable expression of HL in McA-RH7777 cells resulted in decreased (by 40%) incorporation of [(3)H]glycerol into cell-associated and secreted triacylglycerol (TAG) relative to control cells. However, incorporation of [(35)S]methionine/cysteine into cell and medium apoB-100 was not decreased by HL expression. The decreased (3)H-TAG synthesis/secretion in HL expressing cells was not attributable to decreased expression of genes involved in lipogenesis. Fractionation of medium revealed that the decreased [(3)H]TAG from HL expressing cells was mainly attributable to decreased VLDL. Expression of catalytically-inactive HL (HL(SG)) (Ser-145 at the catalytic site was substituted with Gly) in the cells also resulted in decreased secretion of VLDL-[(3)H]TAG. Examination of lumenal contents of microsomes showed a 40% decrease in [(3)H]TAG associated with lumenal lipid droplets in HL or HL(SG) expressing cells as compared with control. The microsomal membrane-associated [(3)H]TAG was decreased by 50% in HL expressing cells but not in HL(SG) expressing cells. Thus, expression of HL, irrespective of its lipolytic function, impairs formation of VLDL precursor [(3)H]TAG in the form of lumenal lipid droplets. These results suggest that HL expression in McA-RH7777 cells result in secretion of [(3)H]TAG-poor VLDL.
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Affiliation(s)
- Michelle Bamji-Mirza
- Department of Biochemistry, Microbiology & Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Canada, K1H 8M5
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Weissglas-Volkov D, Pajukanta P. Genetic causes of high and low serum HDL-cholesterol. J Lipid Res 2010; 51:2032-57. [PMID: 20421590 DOI: 10.1194/jlr.r004739] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Plasma levels of HDL cholesterol (HDL-C) have a strong inherited basis with heritability estimates of 40-60%. The well-established inverse relationship between plasma HDL-C levels and the risk of coronary artery disease (CAD) has led to an extensive search for genetic factors influencing HDL-C concentrations. Over the past 30 years, candidate gene, genome-wide linkage, and most recently genome-wide association (GWA) studies have identified several genetic variations for plasma HDL-C levels. However, the functional role of several of these variants remains unknown, and they do not always correlate with CAD. In this review, we will first summarize what is known about HDL metabolism, monogenic disorders associated with both low and high HDL-C levels, and candidate gene studies. Then we will focus this review on recent genetic findings from the GWA studies and future strategies to elucidate the remaining substantial proportion of HDL-C heritability. Comprehensive investigation of the genetic factors conferring to low and high HDL-C levels using integrative approaches is important to unravel novel pathways and their relations to CAD, so that more effective means of diagnosis, treatment, and prevention will be identified.
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Abstract
PURPOSE OF REVIEW We review stable isotope tracer studies of apolipoprotein B-100 (apoB) kinetics concerning genetic polymorphisms and mutations that affect human lipoprotein metabolism. RECENT FINDINGS In obese men, the allelic combination of the apoB signal peptide, SP24, and cholesteryl ester transfer protein, CETP B1B1, is independently associated with lower VLDL apoB secretion. Microsomal triglyceride transfer protein -493G/T carriers have reduced IDL apoB and LDL apoB production as compared with controls. Mutations in cholesterol transporters (ATP-binding cassette transporter G8 and Niemann-Pick C1 Like 1) are associated with reduced VLDL apoB secretion and increased LDL apoB production and catabolism. The ATP-binding cassette transporter G8 400K variant is a significant, independent predictor of VLDL apoB secretion. Mutations in lipases (lipoprotein lipase and hepatic lipase) and transfer proteins (lecithin-cholesterol acyltransferase and cholesteryl ester transfer protein) alter their functional activity, which impact on VLDL and LDL kinetics. SUMMARY Mutations in genes that regulate intrahepatic apoB assembly and lipid substrate availability to the liver impact on VLDL apoB secretion. Lipoprotein tracer studies can provide functional insight into the potential impact of genetic polymorphisms in regulating apoB metabolism in humans.
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Affiliation(s)
- Theodore W K Ng
- Metabolic Research Centre, School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
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Hodoglugil U, Williamson DW, Mahley RW. Polymorphisms in the hepatic lipase gene affect plasma HDL-cholesterol levels in a Turkish population. J Lipid Res 2009; 51:422-30. [PMID: 19734193 DOI: 10.1194/jlr.p001578] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated the effects of single nucleotide polymorphisms (SNPs) of the hepatic lipase gene (LIPC) on plasma HDL-cholesterol (HDL-C) levels in Turks, a population with low levels of HDL-C. All exons and six evolutionarily conserved regions from 28 Turkish subjects were sequenced. We found 51 SNPs, nine of which were novel. Those 51 SNPs and SNPs from the National Center for Biotechnology Information dbSNP were evaluated by bioinformatics approaches. The population frequencies and linkage disequilibrium among SNPs from HapMap were combined with results from transcriptional factor prediction tools and the literature to select SNPs for genotyping. We found that five tagging LIPC SNPs, two reported here for the first time, were significantly associated with plasma HDL-C levels in both men and women (n = 2,612). These results were replicated in a separate Turkish cohort (n = 1,164). Plasma HDL-C levels were higher in subjects homozygous for the minor alleles of rs4775041, rs1800588 (-514C>T), and rs11858164 and lower in subjects homozygous for the minor alleles of rs11856322 and rs2242061. These SNPs seemed to have independent and additive effects on plasma HDL-C levels (1.5-5.2 mg/dl). Hepatic lipase activity in a subset (n = 260) of the main cohort was also significantly associated with all five SNPs. Thus, five LIPC SNPs, two novel, are associated with plasma HDL-C levels and hepatic lipase activity in two cohorts of Turkish subjects.
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Affiliation(s)
- Ugur Hodoglugil
- Gladstone Institute of Cardiovascular Disease, University of California, San Francisco, CA, USA
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Plengpanich W, Siriwong S, Khovidhunkit W. Two novel mutations and functional analyses of the CETP and LIPC genes underlying severe hyperalphalipoproteinemia. Metabolism 2009; 58:1178-84. [PMID: 19428034 DOI: 10.1016/j.metabol.2009.03.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 03/16/2009] [Indexed: 11/30/2022]
Abstract
Previous studies have shown that CETP and LIPC mutations contribute to hyperalphalipoproteinemia (HALP) in some populations. We investigated whether activities in cholesteryl ester transfer protein (CETP) and hepatic lipase (HL) contribute to HALP in the Thai population and performed genetic analyses of the CETP and LIPC genes. We recruited 38 individuals with high-density lipoprotein cholesterol (HDL-C) levels of at least 2.59 mmol/L (100 mg/dL) (HALP group) and an equal number of individuals with normal serum HDL-C levels (control group). The CETP and HL activities were determined in both groups. Genetic analyses covering all the coding regions and exon-intron junctions of the CETP and LIPC genes were performed in subjects who had low CETP activity and HL activity, respectively. The mean CETP and HL activities were significantly lower in the HALP group than in the control group (34 +/- 4 vs 44 +/- 3 pmol/[microL h], P = .04 and 150 +/- 17 vs 227 +/- 16 nmol free fatty acid/[mL min] P = .002, respectively). Of the 38 individuals with HALP, 19 and 16 were found to have low CETP activity and HL activity, respectively. Of the 19 subjects with low CETP activity, 6 subjects were found to be heterozygous for a known functionally relevant c.1325A>G (D442G) mutation. The other subject was found to be heterozygous for a novel deletion mutation, c.734_737delTCCC mutation. Of the 16 subjects with low HL activity, 8 and 2 subjects were found to be heterozygous for known variants, c.283 G>A (V73M) and c.1068A>C (L334F), respectively. These variants have previously been shown not to be associated with HALP. Another subject was found to be heterozygous for a novel missense mutation, c.421G>A (G119S). Its amino acid change, absence in controls, evolutionary conservation, occurrence in functionally important domain, and predicted damaging function suggested that the G119S mutation is functionally relevant. Two novel mutations in the CETP and LIPC genes found in this study are likely to be the causes of low enzyme activities and elevated HDL-C levels.
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Affiliation(s)
- Wanee Plengpanich
- Biomedical Sciences Program, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand
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Johannsen TH, Kamstrup PR, Andersen RV, Jensen GB, Sillesen H, Tybjaerg-Hansen A, Nordestgaard BG. Hepatic lipase, genetically elevated high-density lipoprotein, and risk of ischemic cardiovascular disease. J Clin Endocrinol Metab 2009; 94:1264-73. [PMID: 19088157 DOI: 10.1210/jc.2008-1342] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT Hepatic lipase influences metabolism of high-density lipoprotein (HDL), a risk factor for ischemic cardiovascular disease (ICD: ischemic heart disease and ischemic cerebrovascular disease). OBJECTIVE We tested the hypothesis that genetic variation in the hepatic lipase genetic variants V73M, N193S, S267F, L334F, T383M, and -480c>t influence levels of lipids, lipoproteins, and apolipoproteins and risk of ICD. DESIGN For the cross-sectional study, we genotyped 9003 individuals from the Copenhagen City Heart Study; hereof were 8971 individuals included in the prospective study, 1747 of whom had incident ICD during 28 yr of follow-up. For the case-control studies, 2110 ischemic heart disease patients vs. 4899 controls and 769 ischemic cerebrovascular disease patients vs. 2836 controls, respectively, were genotyped. Follow-up was 100% complete. RESULTS HDL cholesterol was higher by 0.21 mmol/liter in S267F heterozygotes, by 0.06 mmol/liter in -480c>t heterozygotes, and by 0.13 mmol/liter in -480c>t homozygotes, as compared with noncarriers. These HDL increases theoretically predicted hazard ratios for ICD of 0.87 [95% confidence interval (CI) 0.84-0.90], 0.96 (95% CI 0.95-0.97), and 0.91 (95% CI 0.89-0.94), respectively; this calculation assumes that genetically elevated HDL levels confer decreased risk similar to common HDL elevations. In contrast, when all cases and controls were combined, the observed odds ratios for ICD for these three genetic variants vs. noncarriers were 1.19 (0.76-1.88), 1.04 (0.96-1.13), and 1.08 (0.89-1.30), respectively. Hazard/odds ratios for ICD in carriers vs. noncarriers of the four remaining hepatic lipase genetic variants did not differ consistently from 1.0. CONCLUSION Hepatic lipase genetic variants with elevated levels of HDL cholesterol did not associate with risk of ICD.
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Affiliation(s)
- Trine Holm Johannsen
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, Herlev, Denmark
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Abstract
Lipases are acyl hydrolases that represent a diverse group of enzymes present in organisms ranging from prokaryotes to humans. This article focuses on an evolutionarily related family of extracellular lipases that include lipoprotein lipase, hepatic lipase and endothelial lipase. As newly synthesized proteins, these lipases undergo a series of co- and post-translational maturation steps occurring in the endoplasmic reticulum, including glycosylation and glycan processing, and protein folding and subunit assembly. This article identifies and discusses mechanisms that direct early and late events in lipase folding and assembly. Lipase maturation employs the two general chaperone systems operating in the endoplasmic reticulum, as well as a recently identified lipase-specific chaperone termed lipase maturation factor 1. We propose that the two general chaperone systems act in a coordinated manner early in lipase maturation in order to help create partially folded monomers; lipase maturation factor 1 then facilitates final monomer folding and subunit assembly into fully functional homodimers. Once maturation is complete, the lipases exit the endoplasmic reticulum and are secreted to extracellular sites, where they carry out a number of functions related to lipoprotein and lipid metabolism.
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Affiliation(s)
- Mark H Doolittle
- VA Greater Los Angeles, Healthcare System, 11301 Wilshire Blvd, Bldg 113, Rm 312, Los Angeles, CA 90073, USA, Tel.: +1 661 433 6349
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van Wijk DF, Stroes ESG, Monajemi H. Changing paradigm in HDL metabolism and cellular effects. ACTA ACUST UNITED AC 2009. [DOI: 10.2217/17584299.4.1.17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Nagasaka H, Yorifuji T, Hirano K, Ota A, Toyama-Nakagawa Y, Takatani T, Tsukahara H, Kobayashi K, Takayanagi M, Inomata Y, Uemoto S, Miida T. Effects of bezafibrate on dyslipidemia with cholestasis in children with familial intrahepatic cholestasis-1 deficiency manifesting progressive familial intrahepatic cholestasis. Metabolism 2009; 58:48-54. [PMID: 19059530 DOI: 10.1016/j.metabol.2008.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Accepted: 08/12/2008] [Indexed: 01/18/2023]
Abstract
No appropriate pharmaceutical therapy has been established for dyslipidemia with cholestasis in progressive familial intrahepatic cholestasis (PFIC)-1. We evaluated the efficacy of bezafibrate in PFIC-1. We monitored the clinical presentation and lipoprotein metabolism of 3 patients, aged 3, 4, and 8 years, with FIC1 deficiency, manifesting PFIC-1, over 12 months of bezafibrate therapy. Pruritus was substantially alleviated in the 3 patients after initiation of bezafibrate. Cholestasis was alleviated in 2 of them. Serum high-density lipoprotein cholesterol and low-density lipoprotein cholesterol increased 1.6- to 2.0-fold and 1.1- to 1.2-fold, respectively; but the values remained low and normal, respectively. Serum lipoprotein X, which was at normal levels before treatment, was elevated to levels above the upper limit of the reference range. High serum triglyceride levels decreased by 15% to 30%, to normal levels, after treatment initiation. The activities of lipoprotein lipase and hepatic triglyceride lipase were increased, but those of high-density lipoprotein regulators remained unchanged. Liver expression of multidrug resistance protein-3, which regulates lipoprotein X synthesis, was enhanced by bezafibrate therapy. Bezafibrate treatment favorably affected pruritus, dyslipidemia, and cholestasis in PFIC-1.
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Affiliation(s)
- Hironori Nagasaka
- Division of Metabolism, Chiba Children's Hospital, Chiba 266-0007, Japan
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