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Grejtakova D, Boronova I, Bernasovska J, Bellosta S. PCSK9 and Lipid Metabolism: Genetic Variants, Current Therapies, and Cardiovascular Outcomes. Cardiovasc Drugs Ther 2024:10.1007/s10557-024-07599-5. [PMID: 38907775 DOI: 10.1007/s10557-024-07599-5] [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] [Accepted: 06/12/2024] [Indexed: 06/24/2024]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in the modulation of lipid metabolism as a critical negative regulator of hepatic low-density lipoprotein receptor (LDLR) levels and circulating low-density lipoprotein (LDL) clearance. Numerous gain-of-function (GOF) mutations in PCSK9 have been identified as causing familial hypercholesterolemia (FH) by reducing LDLR levels, and loss-of-function (LOF) mutations associated with a hypercholesterolemia phenotype protective against atherosclerosis. PCSK9 represents an example of successful translational research resulting in the identification of PCSK9 as a major drug target for a lipid-lowering therapy. To explore the genetic constitution of PCSK9 and its biologic role, in this review, we summarize the current evidence of clinically significant PCSK9 genetic variants involved in lipid metabolism as well as emphasize the importance of PCSK9 inhibition for the improvement of cardiovascular outcomes by conducting a meta-analysis of the available data on the incidence of cardiovascular disease events.
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Affiliation(s)
- Daniela Grejtakova
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia.
| | - Iveta Boronova
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia
| | - Jarmila Bernasovska
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia
| | - Stefano Bellosta
- Department of Pharmacological and Biomolecular Sciences "Rodolfo Paoletti", Università Degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
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2
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Rogozik J, Główczyńska R, Grabowski M. Genetic backgrounds and diagnosis of familial hypercholesterolemia. Clin Genet 2024; 105:3-12. [PMID: 37849044 DOI: 10.1111/cge.14435] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/19/2023]
Abstract
Lipid disorders play a critical role in the intricate development of atherosclerosis and its clinical consequences, such as coronary heart disease and stroke. These disorders are responsible for a significant number of deaths in many adult populations worldwide. Familial hypercholesterolemia (FH) is a genetic disorder that causes extremely high levels of LDL cholesterol. The most common mutations occur in genes responsible for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin/kexin type 9 (PCSK9). While genetic testing is a dependable method for diagnosing the disease, it may not detect primary mutations in 20%-40% of FH cases.
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Affiliation(s)
- Joanna Rogozik
- 1st Department of Cardiology, Medical University of Warsaw, Warsaw, Poland
| | - Renata Główczyńska
- 1st Department of Cardiology, Medical University of Warsaw, Warsaw, Poland
| | - Marcin Grabowski
- 1st Department of Cardiology, Medical University of Warsaw, Warsaw, Poland
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3
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Zhao J, Wang R, Song L, Han H, Wang P, Zhao Y, Zhang Y, Zhang H. Causal association between lipid-lowering drugs and female reproductive endocrine diseases: a drug-targeted Mendelian randomization study. Front Endocrinol (Lausanne) 2023; 14:1295412. [PMID: 38027179 PMCID: PMC10668027 DOI: 10.3389/fendo.2023.1295412] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023] Open
Abstract
Purpose The relationship between dyslipidemia and female reproductive endocrine diseases has been increasingly studied. The use of lipid-lowering drugs in treating various related diseases, including coronary heart disease, may affect female reproductive endocrine diseases. Therefore, our study aims to investigate the effects of lipid-lowering drugs on female reproductive endocrine diseases and provide a basis for the appropriate selection of drugs. Methods In this study, we focused on three drug targets of statins, namely HMG-CoA reductase (HMGCR) inhibitors, proprotein convertase kexin 9 (PCSK9) inhibitors, and Niemann-Pick C1-Like 1 (NPC1L1) inhibitors. To identify potential inhibitors for these targets, we collected single nucleotide polymorphisms (SNPs) associated with HMGCR, PCSK9, and NPC1L1 from published genome-wide association study statistics. Subsequently, we conducted a drug target Mendelian randomization (MR) analysis to investigate the effects of these inhibitors on reproductive endocrine diseases mediated by low-density lipoprotein cholesterol (LDL-C) levels. Alongside coronary heart disease as a positive control, our main outcomes of interest included the risk of polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI), premenstrual syndrome (PMS), abnormal uterine bleeding (including menorrhagia and oligomenorrhea), and infertility. Results PCSK9 inhibitors significantly increased the risk of infertility in patients (OR [95%CI] = 1.14 [1.06, 1.23], p<0.05). In contrast, HMGCR inhibitors significantly reduced the risk of menorrhagia in female patients (OR [95%CI] = 0.85 [0.75, 0.97], p<0.05), but had no statistical impact on patients with oligomenorrhea. Conclusion The findings suggest that PCSK9 inhibitors may significantly increase the risk of infertility in patients. On the other hand, HMGCR inhibitors could potentially offer protection against menorrhagia in women. However, no effects of lipid-lowering drugs have been observed on other reproductive endocrine disorders, such as PCOS, POF, PMS and oligomenorrhea.
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Affiliation(s)
- Jing Zhao
- Department of Gynecology, Hebei General Hospital, Shijiazhuang, China
| | - Runfang Wang
- Department of Obstetrics, Hebei General Hospital, Shijiazhuang, China
| | - Liyun Song
- Department of Gynecology, Hebei General Hospital, Shijiazhuang, China
| | - Hua Han
- Department of Gynecology, Hebei General Hospital, Shijiazhuang, China
| | - Pei Wang
- Department of Gynecology, Hebei General Hospital, Shijiazhuang, China
| | - Yuan Zhao
- Department of Clinical Laboratories, Kunhua Affiliated Hospital, Kunming University of Science and Technology, Kunming, China
| | - Yunxia Zhang
- Department of Gynecology, Hebei General Hospital, Shijiazhuang, China
| | - Hongzhen Zhang
- Department of Obstetrics and Gynecology, The First Hospital of Hebei Medical University, Shijiazhuang, China
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Hummelgaard S, Vilstrup JP, Gustafsen C, Glerup S, Weyer K. Targeting PCSK9 to tackle cardiovascular disease. Pharmacol Ther 2023; 249:108480. [PMID: 37331523 DOI: 10.1016/j.pharmthera.2023.108480] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/07/2023] [Accepted: 06/14/2023] [Indexed: 06/20/2023]
Abstract
Lowering blood cholesterol levels efficiently reduces the risk of developing atherosclerotic cardiovascular disease (ASCVD), including coronary artery disease (CAD), which is the main cause of death worldwide. CAD is caused by plaque formation, comprising cholesterol deposits in the coronary arteries. Proprotein convertase subtilisin kexin/type 9 (PCSK9) was discovered in the early 2000s and later identified as a key regulator of cholesterol metabolism. PCSK9 induces lysosomal degradation of the low-density lipoprotein (LDL) receptor in the liver, which is responsible for clearing LDL-cholesterol (LDL-C) from the circulation. Accordingly, gain-of-function PCSK9 mutations are causative of familial hypercholesterolemia, a severe condition with extremely high plasma cholesterol levels and increased ASCVD risk, whereas loss-of-function PCSK9 mutations are associated with very low LDL-C levels and protection against CAD. Since the discovery of PCSK9, extensive investigations in developing PCSK9 targeting therapies have been performed. The combined delineation of clear biology, genetic risk variants, and PCSK9 crystal structures have been major drivers in developing antagonistic molecules. Today, two antibody-based PCSK9 inhibitors have successfully progressed to clinical application and shown to be effective in reducing cholesterol levels and mitigating the risk of ASCVD events, including myocardial infarction, stroke, and death, without any major adverse effects. A third siRNA-based inhibitor has been FDA-approved but awaits cardiovascular outcome data. In this review, we outline the PCSK9 biology, focusing on the structure and nonsynonymous mutations reported in the PCSK9 gene and elaborate on PCSK9-lowering strategies under development. Finally, we discuss future perspectives with PCSK9 inhibition in other severe disorders beyond cardiovascular disease.
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Affiliation(s)
| | | | | | - Simon Glerup
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Draupnir Bio, INCUBA Skejby, Aarhus, Denmark
| | - Kathrin Weyer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
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Shaik NA, Al-Shehri N, Athar M, Awan A, Khalili M, Al Mahadi HB, Hejazy G, Saadah OI, Al-Harthi SE, Elango R, Banaganapalli B, Alefishat E, Awan Z. Protein structural insights into a rare PCSK9 gain-of-function variant (R496W) causing familial hypercholesterolemia in a Saudi family: whole exome sequencing and computational analysis. Front Physiol 2023; 14:1204018. [PMID: 37469559 PMCID: PMC10353052 DOI: 10.3389/fphys.2023.1204018] [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: 04/11/2023] [Accepted: 06/12/2023] [Indexed: 07/21/2023] Open
Abstract
Familial hypercholesterolemia (FH) is a globally underdiagnosed genetic condition associated with premature cardiovascular death. The genetic etiology data on Arab FH patients is scarce. Therefore, this study aimed to identify the genetic basis of FH in a Saudi family using whole exome sequencing (WES) and multidimensional bioinformatic analysis. Our WES findings revealed a rare heterozygous gain-of-function variant (R496W) in the exon 9 of the PCSK9 gene as a causal factor for FH in this family. This variant was absent in healthy relatives of the proband and 200 healthy normolipidemic controls from Saudi Arabia. Furthermore, this variant has not been previously reported in various regional and global population genomic variant databases. Interestingly, this variant is classified as "likely pathogenic" (PP5) based on the variant interpretation guidelines of the American College of Medical Genetics (ACMG). Computational functional characterization suggested that this variant could destabilize the native PCSK9 protein and alter its secondary and tertiary structural features. In addition, this variant was predicted to negatively influence its ligand-binding ability with LDLR and Alirocumab antibody molecules. This rare PCSK9 (R496W) variant is likely to expand our understanding of the genetic basis of FH in Saudi Arabia. This study also provides computational structural insights into the genotype-protein phenotype relationship of PCSK9 pathogenic variants and contributes to the development of personalized medicine for FH patients in the future.
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Affiliation(s)
- Noor Ahmad Shaik
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Princess Al-Jawhara Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Najla Al-Shehri
- Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohammad Athar
- Department of Medical Genetics, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
- Science and Technology Unit, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Ahmed Awan
- Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mariam Khalili
- Department of Pharmacology, College of Medicine, Khalifa University, Abu Dhabi, United Arab Emirates
| | | | - Gehan Hejazy
- Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Omar I. Saadah
- Department of Pediatrics, Pediatric Gastroenterology Unit, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sameer Eida Al-Harthi
- Department of Clinical Pharmacology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ramu Elango
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Princess Al-Jawhara Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Babajan Banaganapalli
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Princess Al-Jawhara Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Eman Alefishat
- Department of Pharmacology, College of Medicine, Khalifa University, Abu Dhabi, United Arab Emirates
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
- Center for Biotechnology, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Zuhier Awan
- Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
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Srivastava RAK. A Review of Progress on Targeting LDL Receptor-Dependent and -Independent Pathways for the Treatment of Hypercholesterolemia, a Major Risk Factor of ASCVD. Cells 2023; 12:1648. [PMID: 37371118 DOI: 10.3390/cells12121648] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/10/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Since the discovery of the LDL receptor in 1973 by Brown and Goldstein as a causative protein in hypercholesterolemia, tremendous amounts of effort have gone into finding ways to manage high LDL cholesterol in familial hypercholesterolemic (HoFH and HeFH) individuals with loss-of-function mutations in the LDL receptor (LDLR) gene. Statins proved to be the first blockbuster drug, helping both HoFH and HeFH individuals by inhibiting the cholesterol synthesis pathway rate-limiting enzyme HMG-CoA reductase and inducing the LDL receptor. However, statins could not achieve the therapeutic goal of LDL. Other therapies targeting LDLR include PCSK9, which lowers LDLR by promoting LDLR degradation. Inducible degrader of LDLR (IDOL) also controls the LDLR protein, but an IDOL-based therapy is yet to be developed. Among the LDLR-independent pathways, such as angiopoietin-like 3 (ANGPTL3), apolipoprotein (apo) B, apoC-III and CETP, only ANGPTL3 offers the advantage of treating both HoFH and HeFH patients and showing relatively better preclinical and clinical efficacy in animal models and hypercholesterolemic individuals, respectively. While loss-of-LDLR-function mutations have been known for decades, gain-of-LDLR-function mutations have recently been identified in some individuals. The new information on gain of LDLR function, together with CRISPR-Cas9 genome/base editing technology to target LDLR and ANGPTL3, offers promise to HoFH and HeFH individuals who are at a higher risk of developing atherosclerotic cardiovascular disease (ASCVD).
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Affiliation(s)
- Rai Ajit K Srivastava
- Integrated Pharma Solutions LLC, Boston, MA 02101-02117, USA
- College of Professional Studies, Northeastern University, Boston, MA 02101-02117, USA
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7
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Abstract
Atherosclerotic cardiovascular disease is the leading cause of death globally. Despite its important risk of premature atherosclerosis and cardiovascular disease, familial hypercholesterolemia (FH) is still largely underdiagnosed worldwide. It is one of the most frequently inherited diseases due to mutations, for autosomal dominant forms, in either of the LDLR, APOB, and PCSK9 genes or possibly a few mutations in the APOE gene and, for the rare autosomal forms, in the LDLRAP1 gene. The discovery of the genes implicated in the disease has largely helped to improve the diagnosis and treatment of FH from the LDLR by Brown and Goldstein, as well as the introduction of statins, to PCSK9 discovery in FH by Abifadel et al., and the very rapid availability of PCSK9 inhibitors. In the last two decades, major progress has been made in clinical and genetic diagnostic tools and the therapeutic arsenal against FH. Improving prevention, diagnosis, and treatment and making them more accessible to all patients will help reduce the lifelong burden of the disease.
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Affiliation(s)
- Marianne Abifadel
- UMR1148, Inserm, Hôpital Bichat-Claude Bernard, 46 rue Henri Huchard, F-75018 Paris, France.,Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie-Santé, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Catherine Boileau
- UMR1148, Inserm, Hôpital Bichat-Claude Bernard, 46 rue Henri Huchard, F-75018 Paris, France.,Département de Génétique, AP-HP, Hôpital Bichat-Claude Bernard, Paris, France
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8
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Alannan M, Seidah NG, Merched AJ. PCSK9 in Liver Cancers at the Crossroads between Lipid Metabolism and Immunity. Cells 2022; 11:cells11244132. [PMID: 36552895 PMCID: PMC9777286 DOI: 10.3390/cells11244132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/01/2022] [Accepted: 12/06/2022] [Indexed: 12/23/2022] Open
Abstract
Metabolic rewiring and defective immune responses are considered to be the main driving forces sustaining cell growth and oncogenesis in many cancers. The atypical enzyme, proprotein convertase subtilisin/kexin type 9 (PCSK9), is produced by the liver in large amounts and plays a major role in lipid metabolism via the control of the low density lipoprotein receptor (LDLR) and other cell surface receptors. In this context, many clinical studies have clearly demonstrated the high efficacy of PCSK9 inhibitors in treating hyperlipidemia and cardiovascular diseases. Recent data implicated PCSK9 in the degradation of major histocompatibility complex I (MHC-I) receptors and the immune system as well as in other physiological activities. This review highlights the complex crosstalk between PCSK9, lipid metabolism and immunosuppression and underlines the latest advances in understanding the involvement of this convertase in other critical functions. We present a comprehensive assessment of the different strategies targeting PCSK9 and show how these approaches could be extended to future therapeutic options to treat cancers with a main focus on the liver.
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Affiliation(s)
- Malak Alannan
- Bordeaux Institute of Oncology (BRIC), INSERM U1312, University of Bordeaux, F-33000 Bordeaux, France
| | - Nabil G. Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute, IRCM, University of Montreal, Montreal, QC H2W 1R7, Canada
| | - Aksam J. Merched
- Bordeaux Institute of Oncology (BRIC), INSERM U1312, University of Bordeaux, F-33000 Bordeaux, France
- Correspondence:
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9
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Therapeutic RNA-silencing oligonucleotides in metabolic diseases. Nat Rev Drug Discov 2022; 21:417-439. [PMID: 35210608 DOI: 10.1038/s41573-022-00407-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 12/14/2022]
Abstract
Recent years have seen unprecedented activity in the development of RNA-silencing oligonucleotide therapeutics for metabolic diseases. Improved oligonucleotide design and optimization of synthetic nucleic acid chemistry, in combination with the development of highly selective and efficient conjugate delivery technology platforms, have established and validated oligonucleotides as a new class of drugs. To date, there are five marketed oligonucleotide therapies, with many more in clinical studies, for both rare and common liver-driven metabolic diseases. Here, we provide an overview of recent developments in the field of oligonucleotide therapeutics in metabolism, review past and current clinical trials, and discuss ongoing challenges and possible future developments.
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10
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Abstract
Dyslipidemias are a group of diseases, which are characterized by abnormal blood concentrations of cholesterol, triglycerides and/or low-density lipoprotein-cholesterol (LDL-c). Dyslipidemia is a determinant condition for the progress of an atherosclerotic plaque formation. The resulting atherogenicity is due to at least two mechanisms: first, to the accumulation in the plasma of lipid particles that have the capacity to alter the function of the endothelium and deposit at the atheromatous plaque, and second, at an insufficient concentration of multifactorial type of high density lipoprotein-cholesterol (HDL-c), whose function is to protect against the development of atherosclerosis. Its highest prevalence is encountered among individuals with diabetes, hypertension or overweight. Hyperlipidemia is one of the main predisposing factors for the development of cardiovascular disease. Hyperlipidemia can be the result of a genetic condition, the secondary expression of a primary process or the consequence of exogenous factors (food, cultural, socio-economic, etc.), all of which lead to the elevation of plasma lipid levels. The objective of this study was to carry out an analysis of the genes involved in the development of dyslipidemias that lead to cardiovascular disease with special emphasis on the proprotein convertase subtilin/kexin type 9 (PCSK9) gene. The PCSK9 gene participates in the development of primary dyslipidemias, mainly familial hypercholesterolemia, currently the pharmacological treatment of choice to reduce LDL-c are statins, however, it has been observed that these have been insufficient to eliminate cardiovascular risk, especially in subjects with primary forms of hypercholesterolemia related to genetic mutations, or statin intolerance.
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11
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Kamar A, Khalil A, Nemer G. The Digenic Causality in Familial Hypercholesterolemia: Revising the Genotype-Phenotype Correlations of the Disease. Front Genet 2021; 11:572045. [PMID: 33519890 PMCID: PMC7844333 DOI: 10.3389/fgene.2020.572045] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 12/01/2020] [Indexed: 12/20/2022] Open
Abstract
Genetically inherited defects in lipoprotein metabolism affect more than 10 million individuals around the globe with preponderance in some parts where consanguinity played a major role in establishing founder mutations. Mutations in four genes have been so far linked to the dominant and recessive form of the disease. Those players encode major proteins implicated in cholesterol regulation, namely, the low-density lipoprotein receptor (LDLR) and its associate protein 1 (LDLRAP1), the proprotein convertase substilin/kexin type 9 (PCSK9), and the apolipoprotein B (APOB). Single mutations or compound mutations in one of these genes are enough to account for a spectrum of mild to severe phenotypes. However, recently several reports have identified digenic mutations in familial cases that do not necessarily reflect a much severe phenotype. Yet, data in the literature supporting this notion are still lacking. Herein, we review all the reported cases of digenic mutations focusing on the biological impact of gene dosage and the potential protective effects of single-nucleotide polymorphisms linked to hypolipidemia. We also highlight the difficulty of establishing phenotype-genotype correlations in digenic familial hypercholesterolemia cases due to the complexity and heterogeneity of the phenotypes and the still faulty in silico pathogenicity scoring system. We finally emphasize the importance of having a whole exome/genome sequencing approach for all familial cases of familial hyperlipidemia to better understand the genetic and clinical course of the disease.
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Affiliation(s)
- Amina Kamar
- Department of Biology, American University of Beirut, Beirut, Lebanon
| | - Athar Khalil
- Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon
| | - Georges Nemer
- Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon
- Division of Genomics and Translational Biomedicine, College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
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12
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Guo Q, Feng X, Zhou Y. PCSK9 Variants in Familial Hypercholesterolemia: A Comprehensive Synopsis. Front Genet 2020; 11:1020. [PMID: 33173529 PMCID: PMC7538608 DOI: 10.3389/fgene.2020.01020] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 08/10/2020] [Indexed: 01/22/2023] Open
Abstract
Autosomal dominant familial hypercholesterolemia (FH) affects approximately 1/250, individuals and potentially leads to elevated blood cholesterol and a significantly increased risk of atherosclerosis. Along with improvements in detection and the increased early diagnosis and treatment, the serious burden of FH on families and society has become increasingly apparent. Since FH is strongly associated with proprotein convertase subtilisin/kexin type 9 (PCSK9), increasing numbers of studies have focused on finding effective diagnostic and therapeutic methods based on PCSK9. At present, as PCSK9 is one of the main pathogenic FH genes, its contribution to FH deserves more explorative research.
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Affiliation(s)
- Qianyun Guo
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
| | - Xunxun Feng
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
| | - Yujie Zhou
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
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13
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Martin WR, Lightstone FC, Cheng F. In Silico Insights into Protein-protein Interaction Disruptive Mutations in the PCSK9-LDLR complex. Int J Mol Sci 2020; 21:E1550. [PMID: 32106405 PMCID: PMC7084799 DOI: 10.3390/ijms21051550] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/10/2020] [Accepted: 02/21/2020] [Indexed: 01/22/2023] Open
Abstract
Gain-of-function mutations in PCSK9 (proprotein convertase subtilisin/kexin type 9) lead to reduced uptake of LDL (low density lipoprotein) cholesterol and, therefore, increased plasma LDL levels. However, the mechanism by which these mutants reduce LDL reuptake is not fully understood. Here, we have used molecular dynamics simulations, MM/PBSA (Molecular Mechanics/Poisson-Boltzmann Surface Area) binding affinity calculations, and residue interaction networks, to investigate the protein-protein interaction (PPI) disruptive effects of two of PCSK9's gain-of-function mutations, Ser127Arg and Asp374Tyr on the PCSK9 and LDL receptor complex. In addition to these PPI disruptive mutants, a third, non-interface mutation (Arg496Trp) is included as a positive control. Our results indicate that Ser127Arg and Asp374Tyr confer significantly improved binding affinity, as well as different binding modes, when compared to the wild-type. These PPI disruptive mutations lie between the EGF(A) (epidermal growth factor precursor homology domain A) of the LDL receptor and the catalytic domain of PCSK9 (Asp374Tyr) and between the prodomain of PCSK9 and the β-propeller of the LDL receptor (Ser127Arg). The interactions involved in these two interfaces result in an LDL receptor that is sterically inhibited from entering its closed conformation. This could potentially implicate the prodomain as a target for small molecule inhibitors.
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Affiliation(s)
- William R. Martin
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA;
| | - Felice C. Lightstone
- Biosciences and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Feixiong Cheng
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA;
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH 44195, USA
- Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
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14
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Sarkar SK, Foo ACY, Matyas A, Asikhia I, Kosenko T, Goto NK, Vergara-Jaque A, Lagace TA. A transient amphipathic helix in the prodomain of PCSK9 facilitates binding to low-density lipoprotein particles. J Biol Chem 2020; 295:2285-2298. [PMID: 31949048 PMCID: PMC7039556 DOI: 10.1074/jbc.ra119.010221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 01/13/2020] [Indexed: 01/07/2023] Open
Abstract
Proprotein convertase subtilisin/kexin type-9 (PCSK9) is a ligand of low-density lipoprotein (LDL) receptor (LDLR) that promotes LDLR degradation in late endosomes/lysosomes. In human plasma, 30–40% of PCSK9 is bound to LDL particles; however, the physiological significance of this interaction remains unknown. LDL binding in vitro requires a disordered N-terminal region in PCSK9's prodomain. Here, we report that peptides corresponding to a predicted amphipathic α-helix in the prodomain N terminus adopt helical structure in a membrane-mimetic environment. This effect was greatly enhanced by an R46L substitution representing an atheroprotective PCSK9 loss-of-function mutation. A helix-disrupting proline substitution within the putative α-helical motif in full-length PCSK9 lowered LDL binding affinity >5-fold. Modeling studies suggested that the transient α-helix aligns multiple polar residues to interact with positively charged residues in the C-terminal domain. Gain-of-function PCSK9 mutations associated with familial hypercholesterolemia (FH) and clustered at the predicted interdomain interface (R469W, R496W, and F515L) inhibited LDL binding, which was completely abolished in the case of the R496W variant. These findings shed light on allosteric conformational changes in PCSK9 required for high-affinity binding to LDL particles. Moreover, the initial identification of FH-associated mutations that diminish PCSK9's ability to bind LDL reported here supports the notion that PCSK9-LDL association in the circulation inhibits PCSK9 activity.
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Affiliation(s)
- Samantha K Sarkar
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Alexander C Y Foo
- Department of Chemistry and Biomolecular Sciences, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Angela Matyas
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Ikhuosho Asikhia
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Tanja Kosenko
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Natalie K Goto
- Department of Chemistry and Biomolecular Sciences, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Ariela Vergara-Jaque
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, Talca, Chile; Millennium Nucleus of Ion Channels-associated Diseases (MiNICAD), 3460000 Talca, Chile
| | - Thomas A Lagace
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada.
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Setia N, Movva S, Balakrishnan P, Biji IK, Sawhney JPS, Puri R, Arora A, Puri RD, Saxena R, Mishra S, Apte S, Kulshrestha S, Ramprasad VL, Verma IC. Genetic analysis of familial hypercholesterolemia in Asian Indians: A single-center study. J Clin Lipidol 2020; 14:35-45. [PMID: 32044282 DOI: 10.1016/j.jacl.2019.12.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND Familial hypercholesterolemia (FH), an autosomal codominant disorder characterized by very high low-density lipoprotein cholesterol, is strongly associated with premature coronary artery disease. OBJECTIVES Molecular landscape of FH in Asian Indians is not well studied, although this ethnic group comprises a large proportion of the world population. Knowledge of mutations in these groups is useful for identifying persons affected with FH, saving their lives, and cascade screening in their relatives. METHODS Potential cases of FH (n = 100) were identified by criteria adapted for the Indian population from Dutch Lipid Clinic Network criteria. Pathogenic variants were analyzed in LDLR, APOB 100 (exons 26 and 29), PCSK9, and APOE genes using Sanger sequencing and multiplex ligation-dependent probe amplification technique. Cases in whom there were no pathogenic variants were tested by next-generation sequencing using a targeted panel of genes. RESULTS Thirty-eight pathogenic variants were identified in 47 of 100 unrelated probands. Of these variants, 33 were identified in LDLR, 3 in APOB, and 2 in PCSK9 genes. Ten pathogenic variants were novel. Mutations were detected in 91.4% of those subjects classified as definite, 40% as probable, and in 18.8% as possible FH cases based on modified Dutch Lipid Clinic Network criteria. A likely founder mutation in intron 10 (c.1587-1G>A) of LDLR gene was observed in 6 North Indian families. The conventional pathogenic variants in APOB and PCSK9 genes and those previously reported in LDLR gene among Asian Indians were not detected in this cohort. CONCLUSION This study demonstrates genetic heterogeneity of FH in India. The variants observed were different from those described in Western populations. Next-generation sequencing technology helped identify new mutations in APOB gene, suggesting that in less-studied populations, it is better to sequence the whole gene rather than test for specific mutations.
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Affiliation(s)
- Nitika Setia
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India.
| | - Sireesha Movva
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Prahlad Balakrishnan
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Ishpreet K Biji
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | | | - Raman Puri
- Department of Cardiology, Indrapratha Apollo Hospital, New Delhi, India
| | - Anjali Arora
- Department of Cardiology, Sir Ganga Ram Hospital, New Delhi, India
| | - Ratna D Puri
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Renu Saxena
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | | | | | - Samarth Kulshrestha
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | | | - Ishwar C Verma
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India.
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16
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In vitro functional characterization of splicing variants of the APOB gene found in familial hypobetalipoproteinemia. J Clin Lipidol 2019; 13:960-969. [PMID: 31629702 DOI: 10.1016/j.jacl.2019.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 08/22/2019] [Accepted: 09/06/2019] [Indexed: 11/23/2022]
Abstract
BACKGROUND Familial hypobetalipoproteinemia type 1 (FHBL-1) is a codominant disorder characterized by greatly reduced plasma levels of total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B. Rare exonic pathogenic variants of APOB gene (nonsense variants, minute deletions/insertions and nonsynonymous variants) have been frequently reported in subjects with FHBL-1. Also, rare intronic variants of APOB located at intron/exon junctions and assumed to affect splicing have been reported. However, the pathogenicity of most of these intronic variants remains to be established. OBJECTIVE The objective of this study was the in vitro functional characterization of six splicing variants of APOB gene identified in seven putative FHBL-1 heterozygotes. METHODS ApoB minigenes harboring each variant were expressed in COS-1 cells and their transcripts were sequenced. RESULTS Four novel variants (c.237+1G>A, c.818+5G>A, c.3000-1G>T, and c.3842+1G>A), predicted in silico to obliterate splice site activity, were found to generate abnormal transcripts. The abnormal transcripts were generated by the activation of cryptic splice sites or exon skipping. All these transcripts harbored a premature termination codon and were predicted to encode truncated apoBs devoid of function. The predicted translation products were: i) p.(Lys41Serfs*2) and p.(Val80Ilefs*10) for c.237+1G>A; ii) p.(Asn274*) for c.818+5G>A; iii) p.(Leu1001Alafs*10) for c.3000-1G>T, and iv) p.(Ser1281Argfs*2) for c.3842+1G>A. Two previously annotated rare variants (c.905-15C>G and c.1618-4G>A) with uncertain effect in silico were found to generate only wild-type transcripts. CONCLUSIONS These in vitro minigene expression studies support the assignment of pathogenicity to four novel splice site variants of APOB gene found in FHBL-1.
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Case-control study on PCSK9 R496W (rs374603772) and D374Y (rs137852912) mutations in Turkish patients with primary dyslipidemia. Anatol J Cardiol 2019; 19:334-340. [PMID: 29724976 PMCID: PMC6280272 DOI: 10.14744/anatoljcardiol.2018.86648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Objective: The aim of this study was to investigate the relationships between F216L (rs28942112), R496W (rs374603772), S127R (rs28942111), and D374Y (rs137852912) PCSK9 gain-of-function (GOF) mutations and primary dyslipidemia and serum lipid levels in patients with primary dyslipidemia. Methods: In this case-control study, DNA was isolated from blood samples collected from patients diagnosed with primary dyslipidemia in cardiology outpatient clinic of Ege University (n=200) and healthy individuals (n=201). F216L, R496W, S127R, and D374Y GOF mutations in the PCSK9 gene were evaluated and genotyped according to the results of melting curve analysis performed in a real-time polymerase chain reaction (PCR) 480 instrument using specific primers for each mutation. Results: There were statistically significant differences between the patient and individuals in control groups in the R496W and D374Y mutations (χ2=10.742 p=0.005; χ2=6.078 p=0.048, respectively). In addition, triglyceride levels in patients with primary dyslipidemia heterozygous for R496W and D374Y mutations were 12.8-fold (p=0.015) and 3.4-fold (p=0.03) higher than that in mutant and wild-type genotype, respectively. Additionally, in the entire study group (n=401), PCSK9 R496W and D374Y mutation carriers had increased total cholesterol (p=0.021), triglycerides (p=0.0001), HDL cholesterol (p=0.028), and low-density lipoproteins (LDL) cholesterol (p=0.028) levels. However, F216L (rs28942112) and S127R (rs28942111) mutations were not detected in patients with primary dyslipidemia and healthy controls. Conclusion: We conclude that the PCSK9 R496W (rs374603772) and D374Y (rs137852912) GOF mutations may be significant risk factors in the development of primary dyslipidemia and may have significant impact on lipid parameters in general population.
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18
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Luirink IK, Braamskamp MJ, Wiegman A, Hartgers ML, Sjouke B, Defesche JC, Hovingh GK. The clinical and molecular diversity of homozygous familial hypercholesterolemia in children: Results from the GeneTics of clinical homozygous hypercholesterolemia (GoTCHA) study. J Clin Lipidol 2019; 13:272-278. [DOI: 10.1016/j.jacl.2018.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/12/2018] [Accepted: 12/14/2018] [Indexed: 11/16/2022]
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Bordicchia M, Spannella F, Ferretti G, Bacchetti T, Vignini A, Di Pentima C, Mazzanti L, Sarzani R. PCSK9 is Expressed in Human Visceral Adipose Tissue and Regulated by Insulin and Cardiac Natriuretic Peptides. Int J Mol Sci 2019; 20:ijms20020245. [PMID: 30634533 PMCID: PMC6358804 DOI: 10.3390/ijms20020245] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/05/2018] [Accepted: 01/04/2019] [Indexed: 01/14/2023] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to and degrades the low-density lipoprotein receptor (LDLR), contributing to hypercholesterolemia. Adipose tissue plays a role in lipoprotein metabolism, but there are almost no data about PCSK9 and LDLR regulation in human adipocytes. We studied PCSK9 and LDLR regulation by insulin, atrial natriuretic peptide (ANP, a potent lipolytic agonist that antagonizes insulin), and LDL in visceral adipose tissue (VAT) and in human cultured adipocytes. PCSK9 was expressed in VAT and its expression was positively correlated with body mass index (BMI). Both intracellular mature and secreted PCSK9 were abundant in cultured human adipocytes. Insulin induced PCSK9, LDLR, and sterol-regulatory element-binding protein-1c (SREBP-1c) and -2 expression (SREBP-2). ANP reduced insulin-induced PCSK9, especially in the context of a medium simulating hyperglycemia. Human LDL induced both mature and secreted PCSK9 and reduced LDLR. ANP indirectly blocked the LDLR degradation, reducing the positive effect of LDL on PCSK9. In conclusion, PCSK9 is expressed in human adipocytes. When the expression of PCSK9 is induced, LDLR is reduced through the PCSK9-mediated degradation. On the contrary, when the induction of PCSK9 by insulin and LDL is partially blocked by ANP, the LDLR degradation is reduced. This suggests that NPs could be able to control LDLR levels, preventing PCSK9 overexpression.
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Affiliation(s)
- Marica Bordicchia
- Internal Medicine and Geriatrics, Department of Clinical and Molecular Sciences, University "Politecnica delle Marche", 60126 Ancona, Italy.
| | - Francesco Spannella
- Internal Medicine and Geriatrics, Department of Clinical and Molecular Sciences, University "Politecnica delle Marche", 60126 Ancona, Italy.
- Internal Medicine and Geriatrics, "Hypertension Excellence Centre" of the European Society of Hypertension, IRCCS-INRCA, 60127 Ancona, Italy.
| | - Gianna Ferretti
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, School of Nutrition, University "Politecnica delle Marche", 60126 Ancona, Italy.
| | - Tiziana Bacchetti
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, School of Nutrition, University "Politecnica delle Marche", 60126 Ancona, Italy.
| | - Arianna Vignini
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, School of Nutrition, University "Politecnica delle Marche", 60126 Ancona, Italy.
| | - Chiara Di Pentima
- Internal Medicine and Geriatrics, Department of Clinical and Molecular Sciences, University "Politecnica delle Marche", 60126 Ancona, Italy.
- Internal Medicine and Geriatrics, "Hypertension Excellence Centre" of the European Society of Hypertension, IRCCS-INRCA, 60127 Ancona, Italy.
| | - Laura Mazzanti
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, School of Nutrition, University "Politecnica delle Marche", 60126 Ancona, Italy.
| | - Riccardo Sarzani
- Internal Medicine and Geriatrics, Department of Clinical and Molecular Sciences, University "Politecnica delle Marche", 60126 Ancona, Italy.
- Internal Medicine and Geriatrics, "Hypertension Excellence Centre" of the European Society of Hypertension, IRCCS-INRCA, 60127 Ancona, Italy.
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20
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Averkova AO, Brazhnik VA, Speshilov GI, Rogozhina AA, Koroleva OS, Zubova EA, Galyavich AS, Tereshenko SN, Boyeva OI, Zateyshchikov DA. Targeted sequencing in patients with clinically diagnosed hereditary lipid metabolism disorder and acute coronary syndrome. BULLETIN OF RUSSIAN STATE MEDICAL UNIVERSITY 2018. [DOI: 10.24075/brsmu.2018.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The actual prevalence of genetic variants causing familial hypercholesterolemia (FH) in every population remains unknown. The aim of this work was to determine the spectrum of pathogenic variants in patients with acute coronary syndrome (ACS) and clinically diagnosed FH using targeted sequencing. We selected 38 patients with ACS from the sample of 2,081 participants of two multicenter observational studies (2004–2007; 2014–2016) who had a clinical diagnosis of FH based on the Dutch Lipid Clinic Network score and Simon Broome criteria. The men and women included in the study were ≤ 55 and ≤ 60 years of age, respectively. Molecular genetic screening was done by targeted next-generation sequencing. We started by sequencing 3 genes associated with FH, including LDLR, APOB, and PCSK9. If no relevant variants were detected, the panel was expanded. Of 38 patients, 24 (63.2%) were shown to have mutations that could cause clinical manifestations of FH and premature coronary artery disease. All patients were heterozygous carriers. Mutations were detected in three “classic” genes LDLR, APOB, and PCSK9 associated with FH, as well as in other genes involved in lipid metabolism, such as APOE, ABCA1, ABCG5, ABCG8, LPL, ANGPTL3, and MTTP. Five variants detected in our study sample had not been described previously: the pathogenic p.Val273_Cys313del variant of the LDLR gene, the likely pathogenic p.Arg160His variant in the APOE gene, two variants of uncertain significance p.Glu612Lys and c.*415G>A in the PCSK9 gene, and the mutant variant p.Ala776Ser in the LDLR gene. We conclude that the use of clinical diagnostic criteria in patients with ACS and FH enables identification of carriers of both “classic” mutations associated with FH and rare genetic variants that can be phenotypically expressed as FH.
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Affiliation(s)
- AO Averkova
- Central State Medical Academy of the Department of Presidential Affairs of the Russian Federation, Moscow
| | - VA Brazhnik
- Central State Medical Academy of the Department of Presidential Affairs of the Russian Federation, Moscow; Municipal Clinical Hospital No. 51, Moscow
| | - GI Speshilov
- Kharkevich Institute for Information Transmission Problems, RAS, Moscow; ReadSense OOO, Troitsk Center for Nanotechnologies of Rusnano Foundation for Nanotechnology Infrastructure and Educational Projects, Moscow
| | - AA Rogozhina
- Central State Medical Academy of the Department of Presidential Affairs of the Russian Federation, Moscow
| | - OS Koroleva
- Central State Medical Academy of the Department of Presidential Affairs of the Russian Federation, Moscow
| | - EA Zubova
- Municipal Clinical Hospital No. 51, Moscow
| | | | - SN Tereshenko
- National Medical Research Center for Cardiology, Moscow
| | - OI Boyeva
- Stavropol State Medical University, Stavropol
| | - DA Zateyshchikov
- Central State Medical Academy of the Department of Presidential Affairs of the Russian Federation, Moscow; Municipal Clinical Hospital No. 51, Moscow
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21
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Martín-Campos JM, Plana N, Figueras R, Ibarretxe D, Caixàs A, Esteve E, Pérez A, Bueno M, Mauri M, Roig R, Martínez S, Pintó X, Masana L, Julve J, Blanco-Vaca F. Autosomal dominant hypercholesterolemia in Catalonia: Correspondence between clinical-biochemical and genetic diagnostics in 967 patients studied in a multicenter clinical setting. J Clin Lipidol 2018; 12:1452-1462. [PMID: 30293936 DOI: 10.1016/j.jacl.2018.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 08/30/2018] [Accepted: 09/04/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Autosomal dominant hypercholesterolemia (ADH) is associated with mutations in the low-density lipoprotein (LDL) receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) genes, and it is estimated to be greatly underdiagnosed. The most cost-effective strategy for increasing ADH diagnosis is a cascade screening from mutation-positive probands. OBJECTIVE The objective of this study was to evaluate the results from 2008 to 2016 of ADH genetic analysis performed in our clinical laboratory, serving most lipid units of Catalonia, a Spanish region with approximately 7.5 million inhabitants. METHODS After the application of the Dutch Lipid Clinic Network (DLCN) clinical diagnostic score for ADH, this information and blood or saliva from 23 different lipid clinic units were investigated in our laboratory. DNA was screened for mutations in LDLR, APOB, and PCSK9, using the DNA-array LIPOchip, the next-generation sequencing SEQPRO LIPO RS platform, and multiplex ligation-dependent probe amplification (MLPA). The Simon Broome Register Group (SBRG) criteria was calculated and analyzed for comparative purposes. RESULTS A total of 967 unrelated samples were analyzed. From this, 158 pathogenic variants were detected in 356 patients. The main components of the DLCN criteria associated with the presence of mutation were plasma LDL cholesterol (LDLc), age, and the presence of tendinous xanthomata. The contribution of family history to the diagnosis was lower than in other studies. DLCN and SBRG were similarly useful for predicting the presence of mutation. CONCLUSION In a real clinical practice, multicenter setting in Catalonia, the percentage of positive genetic diagnosis in patients potentially affected by ADH was 38.6%. The DLCN showed a relatively low capacity to predict mutation detection but a higher one for ruling out mutation.
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Affiliation(s)
- Jesús M Martín-Campos
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain.
| | - Núria Plana
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Rosaura Figueras
- Hospital Universitari de Bellvitge, Servei de Medicina Interna, Unitat de Lípids i Risc Vascular, Universitat de Barcelona, IDIBELL, CIBEROBN, FIPEC, ABS 17 de Setembre, L'Hospitalet/El Prat de Llobregat, Spain
| | - Daiana Ibarretxe
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Assumpta Caixàs
- Hospital Universitari Parc Taulí, Servei d'Endocrinologia i Nutrició, Institut Investigació i Innovació Parc Taulí I3PT-Universitat Autònoma de Barcelona, Sabadell, Spain
| | - Eduardo Esteve
- Hospital Universitari de Girona Dr Josep Trueta, Servei d'Endocrinologia i Nutrició, CIBEROBN, Girona, Spain
| | - Antonio Pérez
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Marta Bueno
- Hospital Universitari Arnau de Vilanova, Servei d'Endocrinologia i Nutrició, Lleida, Spain
| | - Marta Mauri
- Hospital de Terrassa, Servei de Medicina Interna, Terrassa, Spain
| | - Rosa Roig
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Susana Martínez
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Xavier Pintó
- Hospital Universitari de Bellvitge, Servei de Medicina Interna, Unitat de Lípids i Risc Vascular, Universitat de Barcelona, IDIBELL, CIBEROBN, FIPEC, ABS 17 de Setembre, L'Hospitalet/El Prat de Llobregat, Spain
| | - Luís Masana
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Josep Julve
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Francisco Blanco-Vaca
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain.
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Rosenson RS, Hegele RA, Fazio S, Cannon CP. The Evolving Future of PCSK9 Inhibitors. J Am Coll Cardiol 2018; 72:314-329. [DOI: 10.1016/j.jacc.2018.04.054] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/23/2018] [Accepted: 04/25/2018] [Indexed: 01/09/2023]
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Baragetti A, Grejtakova D, Casula M, Olmastroni E, Jotti GS, Norata GD, Catapano AL, Bellosta S. Proprotein Convertase Subtilisin-Kexin type-9 (PCSK9) and triglyceride-rich lipoprotein metabolism: Facts and gaps. Pharmacol Res 2018; 130:1-11. [PMID: 29428206 DOI: 10.1016/j.phrs.2018.01.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 01/24/2023]
Abstract
After more than a decade of intense investigation, Pro-protein Convertase Subtilisin-Kexin type 9 (PCSK9) remains a hot topic of research both at experimental and clinical level. Interestingly PCSK9 is expressed in different tissues suggesting the existence of additional function(s) beyond the modulation of the Low-Density Lipoprotein (LDL) receptor in the liver. Emerging data suggest that PCSK9 might play a role in the modulation of triglyceride-rich lipoprotein (TGRL) metabolism, mainly Very Low-Density Lipoproteins (VLDL) and their remnants. In vitro, PCSK9 affects TGRLs production by intestinal cells as well as the catabolism of LDL receptor homologous and non-homologous targets such as VLDL receptor, CD36 and ApoE2R. However, the in vivo relevance of these findings is still debated. This review aims at critically discussing the role of PCSK9 on TGRLs metabolism with a major focus on the impact of its genetic and pharmacological modulation on circulating lipids and lipoproteins beyond LDL.
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Affiliation(s)
- Andrea Baragetti
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, 20133, Milan, Italy; S.I.S.A. Center for the Study of Atherosclerosis - Bassini Hospital, Cinisello Balsamo, Milan, Italy
| | | | - Manuela Casula
- Epidemiology and Preventive Pharmacology Centre (SEFAP), Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti, 9, 20133 Milano, Italy
| | - Elena Olmastroni
- Epidemiology and Preventive Pharmacology Centre (SEFAP), Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti, 9, 20133 Milano, Italy
| | - Gloria Saccani Jotti
- Department of Medicine & Surgery, Faculty of Medicine, University of Parma, Via Volturno 39, 43121 Parma, Italy
| | - Giuseppe Danilo Norata
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, 20133, Milan, Italy; School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, Kent St., Bentley Western Australia 6102, Australia
| | - Alberico L Catapano
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, 20133, Milan, Italy; IRCCS MultiMedica, via Fantoli 16, 20138, Milan, Italy.
| | - Stefano Bellosta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, 20133, Milan, Italy; IRCCS MultiMedica, via Fantoli 16, 20138, Milan, Italy
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New Sequencing technologies help revealing unexpected mutations in Autosomal Dominant Hypercholesterolemia. Sci Rep 2018; 8:1943. [PMID: 29386597 PMCID: PMC5792649 DOI: 10.1038/s41598-018-20281-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/15/2018] [Indexed: 01/25/2023] Open
Abstract
Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated LDL-C levels leading to coronary heart disease. Four genes are implicated in ADH: LDLR, APOB, PCSK9 and APOE. Our aim was to identify new mutations in known genes, or in new genes implicated in ADH. Thirteen French families with ADH were recruited and studied by exome sequencing after exclusion, in their probands, of mutations in the LDLR, PCSK9 and APOE genes and fragments of exons 26 and 29 of APOB gene. We identified in one family a p.Arg50Gln mutation in the APOB gene, which occurs in a region not usually associated with ADH. Segregation and in-silico analysis suggested that this mutation is disease causing in the family. We identified in another family with the p.Ala3396Thr mutation of APOB, one patient with a severe phenotype carrying also a mutation in PCSK9: p.Arg96Cys. This is the first compound heterozygote reported with a mutation in APOB and PCSK9. Functional studies proved that the p.Arg96Cys mutation leads to increased LDL receptor degradation. This work shows that Next-Generation Sequencing (exome, genome or targeted sequencing) are powerful tools to find new mutations and identify compound heterozygotes, which will lead to better diagnosis and treatment of ADH.
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Bertolini S, Pisciotta L, Fasano T, Rabacchi C, Calandra S. The study of familial hypercholesterolemia in Italy: A narrative review. ATHEROSCLEROSIS SUPP 2017; 29:1-10. [DOI: 10.1016/j.atherosclerosissup.2017.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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PCSK 9 gain-of-function mutations (R496W and D374Y) and clinical cardiovascular characteristics in a cohort of Turkish patients with familial hypercholesterolemia. Anatol J Cardiol 2017; 18:266-272. [PMID: 28777095 PMCID: PMC5731522 DOI: 10.14744/anatoljcardiol.2017.7654] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Objective: The molecular basis of the mutations in the PCSK9 gene that produces familial hypercholesterolemia (FH) in the Turkish population is unknown. This study was conducted to determine the presence of four different PCSK9 gain-of-function (GOF) mutations (F216L, R496W, S127R, and D374Y) in a group of patients with FH. Methods: A total of 80 consecutive patients with FH (mean age: 56±11 years; mean maximum LDL cholesterol: 251±76 mg/dL) were included in the study. Patients with FH were diagnosed according to the Dutch Lipid Clinic Network criteria based on serum cholesterol levels, personal and family histories of cardiovascular disease, tendon xanthomas, and genetic analysis. To identify F216L, R496W, S127R, and D374Y mutations of the PCSK9 gene, high-resolution melting analysis was performed on isolated DNAs. Results: Of the 80 patients, there were 11 patients (13.8%) with PCSK9 GOF mutations. Detected mutations were D374Y mutation in four (5.0%) patients and R496W in seven patients (8.7%). Only one patient was homozygous for R496W mutation. The other two GOF mutations (S127R and F216 variants) were not detected. There was no significant difference with regard to demographic characteristics and CV disease risk factors and clinical course of the disease between the PCSK9 mutation-positive and PCSK9 mutation-negative groups. Conclusion: This is the first study from a Turkish FH cohort, revealing a higher frequency (approximately 14%) of two PCSK9 GOF mutations (D374Y and R496W) and a different disease course compared to the world literature.
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Calandra S, Tarugi P, Bertolini S. Impact of rare variants in autosomal dominant hypercholesterolemia causing genes. Curr Opin Lipidol 2017; 28:267-272. [PMID: 28323660 DOI: 10.1097/mol.0000000000000414] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW The systematic analysis of the major candidate genes in autosomal dominant hypercholesterolemia (ADH) and the use of next-generation sequencing (NGS) technology have made possible the discovery of several rare gene variants whose pathogenic effect in most cases remains poorly defined. RECENT FINDINGS One major advance in the field has been the adoption of a set of international guidelines for the assignment of pathogenicity to low-density lipoprotein receptor (LDLR) gene variants based on the use of softwares, complemented with data available from literature and public databases. The clinical impact of several novel rare variants in LDLR, APOB, PCSK9, APOE genes have been reported in large studies describing patients with ADH found to be homozygotes/compound heterozygotes, double heterozygotes, or simple heterozygotes. In-vitro functional studies have been conducted to clarify the effect of some rare ApoB variants on LDL binding to LDLR and the impact of a rare ApoE variant on the uptake of VLDL and LDL by hepatocytes. SUMMARY The update of the ADH gene variants database and the classification of variants in categories of pathogenicity is a major advance in the understanding the pathophysiology of ADH and in the management of this disorder. The studies of molecularly characterized patients with ADH have emphasized the impact of a specific variant and the variable clinical expression of different genotypes. The functional studies of some variants have increased our understanding of the molecular bases of some forms of ADH.
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Affiliation(s)
- Sebastiano Calandra
- aDepartment of Biomedical, Metabolic and Neural Sciences bDepartment of Life Sciences, University of Modena and Reggio Emilia, Modena cDepartment of Internal Medicine, University of Genova, Genova, Italy
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Dron JS, Hegele RA. Complexity of mechanisms among human proprotein convertase subtilisin-kexin type 9 variants. Curr Opin Lipidol 2017; 28:161-169. [PMID: 28157721 DOI: 10.1097/mol.0000000000000386] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW There are many reports of human variants in proprotein convertase subtilisin-kexin type 9 (PCSK9) that are either gain-of-function (GOF) or loss-of-function (LOF), with downstream effects on LDL cholesterol and cardiovascular disease (CVD) risk. However, data on particular mechanisms have only been minimally curated. RECENT FINDINGS GOF variants are individually ultrarare, affect all domains of the protein, act to reduce LDL receptor expression through several mechanisms, are a minor cause of familial hypercholesterolemia, have been reported mainly within families, have variable LDL cholesterol-raising effects, and are associated with increased CVD risk mainly through observational studies in families and small cohorts. In contrast, LOF variants can be either ultrarare mutations or relatively more common polymorphisms seen in populations, affect all domains of the protein, act to increase LDL receptor expression through several mechanisms, have variable LDL cholesterol-lowering effects, and have been associated with decreased CVD risk mainly through Mendelian randomization studies in epidemiologic populations. SUMMARY There is considerable complexity underlying the clinical concept of both LOF and GOF variants of PCSK9. But despite the underlying mechanistic heterogeneity, altered PCSK9 secretion or function is ultimately correlated with plasma LDL cholesterol level, which is also the driver of CVD outcomes.
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Affiliation(s)
- Jacqueline S Dron
- aRobarts Research Institute bDepartment of Biochemistry cDepartment of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
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Seidah NG, Abifadel M, Prost S, Boileau C, Prat A. The Proprotein Convertases in Hypercholesterolemia and Cardiovascular Diseases: Emphasis on Proprotein Convertase Subtilisin/Kexin 9. Pharmacol Rev 2016; 69:33-52. [DOI: 10.1124/pr.116.012989] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Double-heterozygous autosomal dominant hypercholesterolemia: Clinical characterization of an underreported disease. J Clin Lipidol 2016; 10:1462-1469. [PMID: 27919364 DOI: 10.1016/j.jacl.2016.09.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/25/2016] [Accepted: 09/05/2016] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Autosomal dominant hypercholesterolemia (ADH), characterized by high-plasma low-density lipoprotein cholesterol (LDL-C) levels and premature cardiovascular disease (CVD) risk, is caused by mutations in LDLR, APOB, and/or PCSK9. OBJECTIVE To describe the clinical characteristics of "double-heterozygous carriers," with 2 mutations in 2 different ADH causing genes, that is, LDLR and APOB or LDLR and PCSK9. METHODS Double heterozygotes were identified in the database of the national referral laboratory for DNA diagnostics of inherited dyslipidemias. We collected the medical data (comprising lipids and CVD events) from double heterozygotes and compared these with data from their heterozygous and unaffected relatives and homozygote/compound heterozygous LDLR mutation carriers, identified in a previously described cohort (n = 45). RESULTS A total of 28 double heterozygotes (23 LDLR/APOB and 5 LDLR/PCSK9 mutation carriers) were identified. Off treatment, LDL-C levels were significantly higher in double heterozygotes (mean ± SD, 8.4 ± 2.8 mmol/L) compared with 28 heterozygous (5.6 ± 2.2) and 18 unaffected relatives (2.5 ± 1.1; P ≤ .01 for all comparisons) and significantly lower compared with homozygous/compound heterozygous LDLR mutation carriers (13.0 ± 5.1; P < .001). CONCLUSIONS Double-heterozygous carriers of mutations in ADH genes express an intermediate phenotype compared with heterozygous and homozygous/compound heterozygous carriers and might well be misconceived to suffer from a severe form of heterozygous ADH. The molecular identification of double heterozygosity is of relevance from both a screening and an educational perspective.
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Foody JM, Vishwanath R. Familial hypercholesterolemia/autosomal dominant hypercholesterolemia: Molecular defects, the LDL-C continuum, and gradients of phenotypic severity. J Clin Lipidol 2016; 10:970-986. [DOI: 10.1016/j.jacl.2016.04.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 04/19/2016] [Accepted: 04/26/2016] [Indexed: 01/17/2023]
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Rabacchi C, Bigazzi F, Puntoni M, Sbrana F, Sampietro T, Tarugi P, Bertolini S, Calandra S. Phenotypic variability in 4 homozygous familial hypercholesterolemia siblings compound heterozygous for LDLR mutations. J Clin Lipidol 2016; 10:944-952.e1. [DOI: 10.1016/j.jacl.2016.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/11/2016] [Accepted: 04/12/2016] [Indexed: 12/31/2022]
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Della Badia LA, Elshourbagy NA, Mousa SA. Targeting PCSK9 as a promising new mechanism for lowering low-density lipoprotein cholesterol. Pharmacol Ther 2016; 164:183-94. [PMID: 27133571 DOI: 10.1016/j.pharmthera.2016.04.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Statins and other lipid-lowering drugs have dominated the market for many years for achievement of recommended levels of low-density lipoprotein cholesterol (LDL-C). However, a substantial number of high-risk patients are unable to achieve the LDL-C goal. Proprotein convertase subtilisin/kexin 9 (PCSK9) has recently emerged as a new, promising key therapeutic target for hypercholesterolemia. PCSK9 is a protease involved in chaperoning the low-density lipoprotein receptor to the process of degradation. PCSK9 inhibitors and statins effectively lower LDL-C. The PCSK9 inhibitors decrease the degradation of the LDL receptors, whereas statins mainly interfere with the synthetic machinery of cholesterol by inhibiting the key rate limiting enzyme, the HMG CoA reductase. PCSK9 inhibitors are currently being developed as monoclonal antibodies for their primary use in lowering LDL-C. They may be especially useful for patients with homozygous familial hypercholesterolemia, who at present receive minimal benefit from traditional statin therapy. The monoclonal antibody PCSK9 inhibitors, recently granted FDA approval, show the most promising safety and efficacy profile compared to other, newer LDL-C lowering therapies. This review will primarily focus on the safety and efficacy of monoclonal antibody PCSK9 inhibitors in comparison to statins. The review will also address new, alternative PCSK9 targeting drug classes such as small molecules, gene silencing agents, apolipoprotein B antisense oligonucleotides, and microsomal triglyceride transfer protein inhibitors.
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Affiliation(s)
- Laura A Della Badia
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, USA
| | | | - Shaker A Mousa
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, USA.
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Update on the molecular biology of dyslipidemias. Clin Chim Acta 2016; 454:143-85. [DOI: 10.1016/j.cca.2015.10.033] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/24/2015] [Accepted: 10/30/2015] [Indexed: 12/20/2022]
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Ohta N, Hori M, Takahashi A, Ogura M, Makino H, Tamanaha T, Fujiyama H, Miyamoto Y, Harada-Shiba M. Proprotein convertase subtilisin/kexin 9 V4I variant with LDLR mutations modifies the phenotype of familial hypercholesterolemia. J Clin Lipidol 2016; 10:547-555.e5. [PMID: 27206942 DOI: 10.1016/j.jacl.2015.12.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 12/22/2015] [Indexed: 12/23/2022]
Abstract
BACKGROUND Familial hypercholesterolemia (FH) is caused by mutations in the genes encoding low-density lipoprotein receptor (LDLR), apolipoprotein B, or proprotein convertase subtilisin/kexin 9 (PCSK9). However, FH shows variability of the clinical phenotype modified by other genetic variants or environmental factors. OBJECTIVE Our objective was to determine the distribution of PCSK9 variants in Japanese FH heterozygotes and to clarify whether those variants and the combination of those variants and LDLR mutations modify the clinical phenotypes. METHODS A direct sequence analysis was performed for all 18 exons of LDLR gene and 12 exons of PCSK9 gene in 269 clinically diagnosed FH heterozygotes. The serum lipid levels of the carriers of each variant were compared to those of noncarriers. We also assessed Achilles tendon xanthoma and the prevalence of coronary artery disease (CAD) in the patients aged ≥30 years. RESULTS Eleven PCSK9 variants were detected. There were 4 frequent PCSK9 variants: L21_22insL, A53 V, V4I, and E32 K. The PCSK9 L21_22insL and A53 V were in linkage disequilibrium with each other. There were no significant differences in serum lipids levels and the prevalence of CAD at the age of ≥ 30 years between PCSK9 V4I, L21_22insL/A53 V, or E32 K variant carriers and noncarriers without LDLR mutations. In the patients carrying LDLR mutations and aged ≥ 30 years, the additional PCSK9 V4I variant was linked to a significantly increased prevalence of CAD in accord with the elevation of the LDL-cholesterol level. CONCLUSIONS The addition of the PCSK9 V4I was suggested to modify the phenotype of patients carrying LDLR mutations by affecting their LDLR metabolism.
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Affiliation(s)
- Naotaka Ohta
- Laboratory of Clinical Genetics, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Mika Hori
- Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan.
| | - Atsushi Takahashi
- Omics Research Center, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Masatsune Ogura
- Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Hisashi Makino
- Division of Endocrinology and Metabolism, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Tamiko Tamanaha
- Division of Endocrinology and Metabolism, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Hiromi Fujiyama
- Laboratory of Clinical Genetics, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Yoshihiro Miyamoto
- Laboratory of Clinical Genetics, National Cerebral and Cardiovascular Center, Suita, Japan; Department of Preventive Cardiology, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Mariko Harada-Shiba
- Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan.
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Brautbar A, Leary E, Rasmussen K, Wilson DP, Steiner RD, Virani S. Genetics of familial hypercholesterolemia. Curr Atheroscler Rep 2015; 17:491. [PMID: 25712136 DOI: 10.1007/s11883-015-0491-z] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated low-density lipoprotein (LDL) cholesterol and premature cardiovascular disease, with a prevalence of approximately 1 in 200-500 for heterozygotes in North America and Europe. Monogenic FH is largely attributed to mutations in the LDLR, APOB, and PCSK9 genes. Differential diagnosis is critical to distinguish FH from conditions with phenotypically similar presentations to ensure appropriate therapeutic management and genetic counseling. Accurate diagnosis requires careful phenotyping based on clinical and biochemical presentation, validated by genetic testing. Recent investigations to discover additional genetic loci associated with extreme hypercholesterolemia using known FH families and population studies have met with limited success. Here, we provide a brief overview of the genetic determinants, differential diagnosis, genetic testing, and counseling of FH genetics.
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Affiliation(s)
- Ariel Brautbar
- Division of Genetics, Cook Children's Medical Center, Fort Worth, TX, USA,
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Le QT, Blanchet M, Seidah NG, Labonté P. Plasma Membrane Tetraspanin CD81 Complexes with Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) and Low Density Lipoprotein Receptor (LDLR), and Its Levels Are Reduced by PCSK9. J Biol Chem 2015. [PMID: 26195630 DOI: 10.1074/jbc.m115.642991] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an important factor in plasma cholesterol regulation through modulation of low density lipoprotein receptor (LDLR) levels. Naturally occurring mutations can lead to hyper- or hypocholesterolemia in human. Recently, we reported that PCSK9 was also able to modulate CD81 in Huh7 cells. In the present study, several gain-of-function and loss-of-function mutants as well as engineered mutants of PCSK9 were compared for their ability to modulate the cell surface expression of LDLR and CD81. Although PCSK9 gain-of-function D374Y enhanced the degradation both receptors, D374H and D129N seemed to only reduce LDLR levels. In contrast, mutations in the C-terminal hinge-cysteine-histidine-rich domain segment primarily affected the PCSK9-induced CD81 degradation. Furthermore, when C-terminally fused to an ACE2 transmembrane anchor, the secretory N-terminal catalytic or hinge-cysteine-histidine-rich domain domains of PCSK9 were able to reduce CD81 and LDLR levels. These data confirm that PCSK9 reduces CD81 levels via an intracellular pathway as reported for LDLR. Using immunocytochemistry, a proximity ligation assay, and co-immunoprecipitation, we found that the cell surface level of PCSK9 was enhanced upon overexpression of CD81 and that both PCSK9 and LDLR interact with this tetraspanin protein. Interestingly, using CHO-A7 cells lacking LDLR expression, we revealed that LDLR was not required for the degradation of CD81 by PCSK9, but its presence strengthened the PCSK9 effect.
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Affiliation(s)
- Quoc-Tuan Le
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada, Department of Malaria, Parasitology and Entomology, Vietnam Military Medical University, 104 Phung Hung Street, Ha Dong District, Hanoi 151000, Vietnam, and
| | - Matthieu Blanchet
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada
| | - Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada
| | - Patrick Labonté
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada,
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Living the PCSK9 adventure: from the identification of a new gene in familial hypercholesterolemia towards a potential new class of anticholesterol drugs. Curr Atheroscler Rep 2015; 16:439. [PMID: 25052769 DOI: 10.1007/s11883-014-0439-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A decade after our discovery of the involvement of proprotein convertase subtilisin/kexin type 9 (PCSK9) in cholesterol metabolism through the identification of the first mutations leading to hypercholesterolemia, PCSK9 has become one of the most promising targets in cholesterol and cardiovascular diseases. This challenging work in the genetics of hypercholesterolemia paved the way for a plethora of studies around the world allowing the characterization of PCSK9, its expression, its impact on reducing the abundance of LDL receptor, and the identification of loss-of-function mutations in hypocholesterolemia. We highlight the different steps of this adventure and review the published clinical trials especially those with the anti-PCSK9 antibodies evolocumab (AMG 145) and alirocumab (SAR236553/REGN727), which are in phase III trials. The promising results in lowering LDL cholesterol levels raise hope that the PCSK9 adventure will lead, after the large and long-term ongoing phase III studies evaluating efficacy and safety, to a new anticholesterol pharmacological class.
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LDL apheresis in the treatment of familial hypercholesterolemia: Experience of Hospital Santo António, Porto. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2015. [DOI: 10.1016/j.repce.2014.07.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Palma I, Caldas AR, Palma IM, Queirós JA, Madureira A, Oliveira JC, Palma P, Correia C, Ramos MH. LDL‐aférese no tratamento de hipercolesterolemia familiar: experiência do Hospital Santo António. Rev Port Cardiol 2015; 34:163-72. [DOI: 10.1016/j.repc.2014.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 05/07/2014] [Accepted: 07/31/2014] [Indexed: 12/31/2022] Open
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Sirtori CR, Pavanello C, Bertolini S. Microsomal transfer protein (MTP) inhibition-a novel approach to the treatment of homozygous hypercholesterolemia. Ann Med 2014; 46:464-74. [PMID: 24987866 DOI: 10.3109/07853890.2014.931100] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Homozygous familial hypercholesterolemia (HoFH) represents the most severe lipoprotein disorder, generally attributable to mutation(s) of the low-density lipoprotein receptor (LDL-R), i.e. autosomal dominant hypercholesterolemia type 1 (ADH1). Much lower percentages are due to alterations of apolipoprotein B (ADH2), or gain-of-function mutations of proprotein convertase subtilisin/kexin type 9 (PCSK9) (ADH3). In certain geographical areas a significant number of patients may be affected by an autosomal recessive hypercholesterolemia (ARH). Mutations may be also combined (two mutations of the same gene, compound heterozygosity), or two in different genes (double heterozygosity). Among the most innovative therapeutic approaches made available recently, inhibitors of the microsomal transfer protein (MTP) system have shown a high clinical potential. MTP plays a critical role in the assembly/secretion of very-low-density lipoproteins (VLDL), and its absence leads to apo B deficiency. MTP antagonists dramatically lower LDL-cholesterol (LDL-C) in animals, although a reported increase of liver fat delayed their clinical development. Lomitapide, the best-studied MTP inhibitor, reduces LDL-C by 50% or more in HoFH patients, with modest, reversible, liver steatosis. Recent US approval has confirmed an acceptable tolerability, provided patients adhere to a strictly low-fat regimen. There are no clinical data on atherosclerosis reduction/regression, but animal models provide encouraging results.
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Mabuchi H, Nohara A, Noguchi T, Kobayashi J, Kawashiri MA, Inoue T, Mori M, Tada H, Nakanishi C, Yagi K, Yamagishi M, Ueda K, Takegoshi T, Miyamoto S, Inazu A, Koizumi J. Genotypic and phenotypic features in homozygous familial hypercholesterolemia caused by proprotein convertase subtilisin/kexin type 9 (PCSK9) gain-of-function mutation. Atherosclerosis 2014; 236:54-61. [PMID: 25014035 DOI: 10.1016/j.atherosclerosis.2014.06.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 06/09/2014] [Accepted: 06/10/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUNDS Familial hypercholesterolemia (FH) is an autosomal dominant disease characterized by hypercholesterolemia, tendon xanthomas, and premature coronary heart disease. FH is caused by mutations of "FH genes," which include the LDL-receptor (LDLR), apolipoprotein B-100 (APOB) or proprotein convertase subtilisin/kexin type 9 (PCSK9). We evaluated the usefulness of FH gene analysis for diagnosing homozygous FH (homo-FH), particularly in cases caused by gain-of-function (g-o-f) mutations in PCSK9 (PCSK9 E32K). OBJECTIVES To evaluate the frequency of homo-FH caused by PCSK9 E32K compared with FH due to other genetic causes and to report the phenotypic features of homo-FH caused by PCSK9 E32K. METHODS Genomic DNA was prepared from white blood cells, and LDLR and PCSK9 mutations were identified using the Invader assay method. RESULTS Of the 1055 hetero-FH patients, 62 patients (5.9%) carried the PCSK9 E32K mutation, while in the 82 alleles of 41 homo-FH patients, 13 (15.9%) had double mutations of LDLR allele and PCSK9 E32K mutation. Mean plasma total cholesterol (TC) (9.93 ± 2.95 mmol/L, mean ± SD) in true homo-FH cases with PCSK9 E32K or double hetero-FH cases with PCSK9 E32K and LDLR mutations were significantly lower than those in true homo-FH (18.06 ± 4.96 mmol/L) and compound heterozygous cases with LDLR mutations (14.84 ± 1.62 mmol/L). Mean plasma TC concentrations in the 59 hetero-FH cases with PCSK9 E32K (7.21 ± 1.55 mmol/L) were significantly lower than those (8.94 ± 1.53 mmol/L) in the hetero-FH by LDLR mutations. CONCLUSIONS FH caused by PCSK9 g-o-f mutations is relatively common in Japan and causes a mild type of homo- and hetero-FH compared with FH caused by LDLR mutations.
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Affiliation(s)
- Hiroshi Mabuchi
- Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8640, Japan.
| | - Atsushi Nohara
- Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8640, Japan
| | - Tohru Noguchi
- Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8640, Japan
| | - Junji Kobayashi
- Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8640, Japan
| | - Masa-aki Kawashiri
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Takeshi Inoue
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Mika Mori
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Hayato Tada
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Chiaki Nakanishi
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Kunimasa Yagi
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Masakazu Yamagishi
- Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | | | | | | | - Akihiro Inazu
- Laboratory Science, Graduate School of Medical Science, Kanazawa University, Japan
| | - Junji Koizumi
- General Medicine, Graduate School of Medical Science, Kanazawa University, Japan
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Panno MD, Cefalù AB, Averna MR. Lomitapide: a novel drug for homozygous familial hypercholesterolemia. ACTA ACUST UNITED AC 2014. [DOI: 10.2217/clp.13.74] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Schiele F, Park J, Redemann N, Luippold G, Nar H. An Antibody against the C-Terminal Domain of PCSK9 Lowers LDL Cholesterol Levels In Vivo. J Mol Biol 2014; 426:843-52. [DOI: 10.1016/j.jmb.2013.11.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/11/2013] [Accepted: 11/12/2013] [Indexed: 10/26/2022]
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Elshourbagy NA, Meyers HV, Abdel-Meguid SS. Cholesterol: the good, the bad, and the ugly - therapeutic targets for the treatment of dyslipidemia. Med Princ Pract 2013; 23:99-111. [PMID: 24334831 PMCID: PMC5586853 DOI: 10.1159/000356856] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 10/27/2013] [Indexed: 01/06/2023] Open
Abstract
Maintaining cholesterol and triglyceride (TG) levels within healthy limits is critical for decreasing the risk of heart disease. Dyslipidemia refers to the abnormal levels of lipids in the blood, including low high-density lipoprotein cholesterol (HDL-C), also known as good cholesterol, high low-density lipoprotein cholesterol (LDL-C), also known as bad cholesterol, and/or high TG levels that contribute to the development and progression of atherosclerosis. In this article we reviewed some of the current therapeutic targets for the treatment of dyslipidemia, with a primary focus on endothelial lipase and lecithin cholesterol acyl transferase for raising HDL-C, and the proprotein convertase subtilisin-like kexin type 9 (PCSK9), microsomal triglyceride transfer protein, and the messenger RNA of apolipoprotein B for lowering LDL-C. In addition, we reviewed the role of apolipoprotein AI (apoAI) in raising HDL-C, where we discuss three apoAI-based drugs under development. These are its mutated dimer (apoAI-Milano), a complex with phospholipids, and a mimetic peptide. Atherosclerosis, mainly because of dyslipidemia, is a leading cause of cardiovascular disease. Regarding the title of this article, the 'good' refers to HDL-C, the 'bad' refers to LDL-C, and the 'ugly' refers to atherosclerosis.
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Cooper DN, Krawczak M, Polychronakos C, Tyler-Smith C, Kehrer-Sawatzki H. Where genotype is not predictive of phenotype: towards an understanding of the molecular basis of reduced penetrance in human inherited disease. Hum Genet 2013; 132:1077-130. [PMID: 23820649 PMCID: PMC3778950 DOI: 10.1007/s00439-013-1331-2] [Citation(s) in RCA: 417] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/15/2013] [Indexed: 02/06/2023]
Abstract
Some individuals with a particular disease-causing mutation or genotype fail to express most if not all features of the disease in question, a phenomenon that is known as 'reduced (or incomplete) penetrance'. Reduced penetrance is not uncommon; indeed, there are many known examples of 'disease-causing mutations' that fail to cause disease in at least a proportion of the individuals who carry them. Reduced penetrance may therefore explain not only why genetic diseases are occasionally transmitted through unaffected parents, but also why healthy individuals can harbour quite large numbers of potentially disadvantageous variants in their genomes without suffering any obvious ill effects. Reduced penetrance can be a function of the specific mutation(s) involved or of allele dosage. It may also result from differential allelic expression, copy number variation or the modulating influence of additional genetic variants in cis or in trans. The penetrance of some pathogenic genotypes is known to be age- and/or sex-dependent. Variable penetrance may also reflect the action of unlinked modifier genes, epigenetic changes or environmental factors. At least in some cases, complete penetrance appears to require the presence of one or more genetic variants at other loci. In this review, we summarize the evidence for reduced penetrance being a widespread phenomenon in human genetics and explore some of the molecular mechanisms that may help to explain this enigmatic characteristic of human inherited disease.
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Affiliation(s)
- David N. Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN UK
| | - Michael Krawczak
- Institute of Medical Informatics and Statistics, Christian-Albrechts University, 24105 Kiel, Germany
| | | | - Chris Tyler-Smith
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK
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Ye Y, Li K, Liu J, Li M, Wang W, Wang R, Zou J, Xie P, Wei L, Jiao G, Yuan Z. Dysfunctional co-expression network analysis of familial hypercholesterolemia. J Cardiol 2013; 62:58-62. [DOI: 10.1016/j.jjcc.2013.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 02/04/2013] [Accepted: 02/11/2013] [Indexed: 10/26/2022]
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Spectrum of mutations and phenotypic expression in patients with autosomal dominant hypercholesterolemia identified in Italy. Atherosclerosis 2013; 227:342-8. [DOI: 10.1016/j.atherosclerosis.2013.01.007] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/03/2013] [Accepted: 01/09/2013] [Indexed: 11/19/2022]
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Pisciotta L, Sallo R, Rabacchi C, Wunsch A, Calandra S, Bertolini S. Leucine 10 allelic variant in signal peptide of PCSK9 increases the LDL cholesterol-lowering effect of statins in patients with familial hypercholesterolaemia. Nutr Metab Cardiovasc Dis 2012; 22:831-835. [PMID: 21920719 DOI: 10.1016/j.numecd.2011.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 03/31/2011] [Accepted: 04/05/2011] [Indexed: 10/17/2022]
Abstract
BACKGROUND AND AIMS In the normal population, carriers of an additional leucine residue in a stretch of nine leucines in the signal peptide of PCSK9 (L10) have lower total (TC) and low-density lipoprotein cholesterol (LDL-C) than homozygotes for the wild-type allele (L9/L9). A similar effect was detected in familial hypercholesterolaemia (FH) patients with the p.C681X mutation of LDL-receptor (LDLR). We investigated the effect of L10 variant on basal lipid profile and response to statins in molecularly characterised FH patients. METHODS AND RESULTS Plasma lipids were determined in 322 FH patients screened for the L9/L10/L11 polymorphism and in a subgroup of 54 patients carrying the same LDLR mutation (p.Q474HfsX63). Plasma lipids were also determined in 42 FH patients carrying the L10 variant and in a parallel group of 42 FH patients, L9/L9 homozygotes, matched for gender, age, type of LDLR gene mutation, as well as for type, dose and duration of statin treatment. In FH patients, no difference in the basal plasma TC and LDL-C levels was observed between carriers of L10 variant (L9/L10+L10/L10) and L9/L9 homozygotes. The same was true in FH patients carrying the p.Q474HfsX63 LDLR mutation. In the subgroups of statin-treated patients, the reduction of TC and LDL-C was greater in carriers of L10 (-34.0% and -42.5%, respectively) than in L9/L9 homozygotes (-27.5% and -34.3%, respectively) (P<0.001). CONCLUSION The variant L10 of the leucine repeats in PCSK9 signal peptide is to be considered as a factor capable of modulating the lipid-lowering effects of statins in FH.
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Affiliation(s)
- L Pisciotta
- Department of Internal Medicine, University of Genoa, Viale Benedetto XV 6, I-16132 Genoa, Italy
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Ferri N. Proprotein convertase subtilisin/kexin type 9: from the discovery to the development of new therapies for cardiovascular diseases. SCIENTIFICA 2012; 2012:927352. [PMID: 24278757 PMCID: PMC3820617 DOI: 10.6064/2012/927352] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 08/28/2012] [Indexed: 06/02/2023]
Abstract
The identification of the HMG-CoA reductase inhibitors, statins, has represented a dramatic innovation of the pharmacological modulation of hypercholesterolemia and associated cardiovascular diseases. However, not all patients receiving statins achieve guideline-recommended low density lipoprotein (LDL) cholesterol goals, particularly those at high risk. There remains, therefore, an unmet medical need to develop additional well-tolerated and effective agents to lower LDL cholesterol levels. The discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9), a secretory protein that posttranscriptionally regulates levels of low density lipoprotein receptor (LDLR) by inducing its degradation, has opened a new era of pharmacological modulation of cholesterol homeostasis. This paper summarizes the current knowledge of the basic molecular mechanism underlying the regulatory effect of LDLR expression by PCSK9 obtained from in vitro cell-cultured studies and the analysis of the crystal structure of PCSK9. It also describes the epidemiological and experimental evidences of the regulatory effect of PCSK9 on LDL cholesterol levels and cardiovascular diseases and summarizes the different pharmacological approaches under development for inhibiting PCSK9 expression, processing, and the interaction with LDLR.
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Affiliation(s)
- Nicola Ferri
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milano, Italy
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