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Jiang Y, Zhu X, Jordan K, Li Y, Conley S, Tang H, Lerman A, Eirin A, Ou T, Lerman LO. Dyslipidemia-induced renal fibrosis related to ferroptosis and endoplasmic reticulum stress. J Lipid Res 2024; 65:100610. [PMID: 39094771 PMCID: PMC11401224 DOI: 10.1016/j.jlr.2024.100610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 07/18/2024] [Accepted: 07/20/2024] [Indexed: 08/04/2024] Open
Abstract
Dyslipidemia may induce chronic kidney disease and trigger both ferroptosis and endoplasmic reticulum (ER) stress, but the instigating factors are incompletely understood. We tested the hypothesis that different models of dyslipidemia engage distinct kidney injury mechanisms. Wild-type (WT) or proprotein-convertase subtilisin/kexin type-9 (PCSK9)-gain-of-function (GOF) Ossabaw pigs were fed with a 6-month normal diet (ND) or high-fat diet (HFD) (n = 5-6 each). Renal function and fat deposition were studied in vivo using CT, and blood and kidney tissue studied ex-vivo for lipid profile, systemic and renal vein FFAs levels, and renal injury mechanisms including lipid peroxidation, ferroptosis, and ER stress. Compared with WT-ND pigs, both HFD and PCSK9-GOF elevated triglyceride levels, which were highest in WT-HFD, whereas total and LDL cholesterol levels rose only in PCSK9-GOF pigs, particularly in PCSK9-GOF/HFD. The HFD groups had worse kidney function than the ND groups. The WT-HFD kidneys retained more FFA than other groups, but all kidneys developed fibrosis. Furthermore, HFD-induced ferroptosis in WT-HFD indicated by increased free iron, lipid peroxidation, and decreased glutathione peroxidase-4 mRNA expression, while PCSK9-GOF induced ER stress with upregulated GRP94 and CHOP protein expression. In vitro, pig kidney epithelial cells treated with palmitic acid and oxidized LDL to mimic HFD and PCSK9-GOF showed similar trends to those observed in vivo. Taken together, HFD-induced hypertriglyceridemia promotes renal FFA retention and ferroptosis, whereas PCSK9-GOF-induced hypercholesterolemia elicits ER stress, both resulting in renal fibrosis. These observations suggest different targets for preventing and treating renal fibrosis in subjects with specific types of dyslipidemia.
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Affiliation(s)
- Yamei Jiang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA; Department of Urology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Xiangyang Zhu
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Kyra Jordan
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Yongxin Li
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Sabena Conley
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Hui Tang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Amir Lerman
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Alfonso Eirin
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Tongwen Ou
- Department of Urology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lilach O Lerman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
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Katsuki S, Jha PK, Aikawa E, Aikawa M. The role of proprotein convertase subtilisin/kexin 9 (PCSK9) in macrophage activation: a focus on its LDL receptor-independent mechanisms. Front Cardiovasc Med 2024; 11:1431398. [PMID: 39149582 PMCID: PMC11324467 DOI: 10.3389/fcvm.2024.1431398] [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: 05/11/2024] [Accepted: 07/15/2024] [Indexed: 08/17/2024] Open
Abstract
Recent clinical trials demonstrated that proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors reduce cardiovascular events without affecting systemic inflammation in the patients with coronary artery disease, as determined by high sensitivity C-reactive protein (CRP) levels. However, its pro-inflammatory effects in cardiovascular disease in humans and experimental animals beyond the traditional cholesterol receptor-dependent lipid metabolism have also called attention of the scientific community. PCSK9 may target receptors associated with inflammation other than the low-density lipoprotein receptor (LDLR) and members of the LDLR family. Accumulating evidence suggests that PCSK9 promotes macrophage activation not only via lipid-dependent mechanisms, but also lipid-independent and LDLR-dependent or -independent mechanisms. In addition to dyslipidemia, PCSK9 may thus be a potential therapeutic target for various pro-inflammatory diseases.
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Affiliation(s)
- Shunsuke Katsuki
- Department of Cardiovascular Medicine, Kyushu University Hospital, Fukuoka, Japan
- Center for Excellence in Vascular Biology, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Prabhash Kumar Jha
- Center for Excellence in Vascular Biology, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Elena Aikawa
- Center for Excellence in Vascular Biology, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Masanori Aikawa
- Center for Excellence in Vascular Biology, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
- Channing Division of Network Medicine (MA), Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, Boston, MA, United States
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Hendershot LM, Buck TM, Brodsky JL. The Essential Functions of Molecular Chaperones and Folding Enzymes in Maintaining Endoplasmic Reticulum Homeostasis. J Mol Biol 2024; 436:168418. [PMID: 38143019 DOI: 10.1016/j.jmb.2023.168418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/26/2023]
Abstract
It has been estimated that up to one-third of the proteins encoded by the human genome enter the endoplasmic reticulum (ER) as extended polypeptide chains where they undergo covalent modifications, fold into their native structures, and assemble into oligomeric protein complexes. The fidelity of these processes is critical to support organellar, cellular, and organismal health, and is perhaps best underscored by the growing number of disease-causing mutations that reduce the fidelity of protein biogenesis in the ER. To meet demands encountered by the diverse protein clientele that mature in the ER, this organelle is populated with a cadre of molecular chaperones that prevent protein aggregation, facilitate protein disulfide isomerization, and lower the activation energy barrier of cis-trans prolyl isomerization. Components of the lectin (glycan-binding) chaperone system also reside within the ER and play numerous roles during protein biogenesis. In addition, the ER houses multiple homologs of select chaperones that can recognize and act upon diverse peptide signatures. Moreover, redundancy helps ensure that folding-compromised substrates are unable to overwhelm essential ER-resident chaperones and enzymes. In contrast, the ER in higher eukaryotic cells possesses a single member of the Hsp70, Hsp90, and Hsp110 chaperone families, even though several homologs of these molecules reside in the cytoplasm. In this review, we discuss specific functions of the many factors that maintain ER quality control, highlight some of their interactions, and describe the vulnerabilities that arise from the absence of multiple members of some chaperone families.
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Affiliation(s)
- Linda M Hendershot
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, United States.
| | - Teresa M Buck
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
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Kehinde IO, Akawa O, Adewumi AT, Rabbad AH, Soliman MES. PCSK9 inhibitors as safer therapeutics for atherosclerotic cardiovascular disease (ASCVD): Pharmacophore design and molecular dynamics analysis. J Cell Biochem 2024; 125:e30581. [PMID: 38747499 DOI: 10.1002/jcb.30581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 07/12/2024]
Abstract
Cardiovascular disorders are still challenging and are among the deadly diseases. As a major risk factor for atherosclerotic cardiovascular disease, dyslipidemia, and high low-density lipoprotein cholesterol in particular, can be prevented primary and secondary by lipid-lowering medications. Therefore, insights are still needed into designing new drugs with minimal side effects. Proprotein convertase subtilisin/kexin 9 (PCSK9) enzyme catalyses protein-protein interactions with low-density lipoprotein, making it a critical target for designing promising inhibitors compared to statins. Therefore, we screened for potential compounds using a redesigned PCSK9 conformational behaviour to search for a significantly extensive chemical library and investigated the inhibitory mechanisms of the final compounds using integrated computational methods, from ligand essential functional group screening to all-atoms MD simulations and MMGBSA-based binding free energy. The inhibitory mechanisms of the screened compounds compared with the standard inhibitor. K31 and K34 molecules showed stronger interactions for PCSK9, having binding energy (kcal/mol) of -33.39 and -63.51, respectively, against -27.97 of control. The final molecules showed suitable drug-likeness, non-mutagenesis, permeability, and high solubility values. The C-α atoms root mean square deviation and root mean square fluctuation of the bound-PCSK9 complexes showed stable and lower fluctuations compared to apo PCSK9. The findings present a model that unravels the mechanism by which the final molecules proposedly inhibit the PCSK9 function and could further improve the design of novel drugs against cardiovascular diseases.
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Affiliation(s)
- Ibrahim O Kehinde
- Molecular Bio-computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, South Africa
- Department of Pharmaceutical and Medicinal Chemistry, College of Pharmacy, Afe Babalola University, Ado-Ekiti, Nigeria
| | - Oluwole Akawa
- Department of Pharmaceutical and Medicinal Chemistry, College of Pharmacy, Afe Babalola University, Ado-Ekiti, Nigeria
| | - Adeniyi T Adewumi
- Department of Life and Consumer Sciences, University of South Africa, Florida Campus, Johannesburg, South Africa
| | - Ali H Rabbad
- Molecular Bio-computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, South Africa
| | - Mahmoud E S Soliman
- Molecular Bio-computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, South Africa
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Cao Zhang AM, Ziogos E, Harb T, Gerstenblith G, Leucker TM. Emerging clinical role of proprotein convertase subtilisin/kexin type 9 inhibition-Part one: Pleiotropic pro-atherosclerotic effects of PCSK9. Eur J Clin Invest 2024:e14273. [PMID: 38922860 DOI: 10.1111/eci.14273] [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] [Received: 04/03/2024] [Revised: 05/20/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND Proprotein convertase subtilisin/kexin type 9 (PCSK9) is primarily recognized for its role in lipid metabolism, but recent evidence suggests that it may have broader implications due to its diverse tissue expression. OBJECTIVE This review aims to explore the multifaceted functions of PCSK9, highlighting its pro-atherosclerotic effects, including its impact on circulating lipoprotein variables, non-low-density lipoprotein receptors, and various cell types involved in atherosclerotic plaque development. CONCLUSIONS PCSK9 exhibits diverse roles beyond lipid metabolism, potentially contributing to atherosclerosis through multiple pathways. Understanding these mechanisms could offer new insights into therapeutic strategies targeting PCSK9 for cardiovascular disease management.
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Affiliation(s)
- Alexander M Cao Zhang
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Efthymios Ziogos
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Tarek Harb
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Gary Gerstenblith
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Thorsten M Leucker
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Dobson JR, Jacobson DA. Disrupted Endoplasmic Reticulum Ca 2+ Handling: A Harβinger of β-Cell Failure. BIOLOGY 2024; 13:379. [PMID: 38927260 PMCID: PMC11200644 DOI: 10.3390/biology13060379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/17/2024] [Accepted: 05/17/2024] [Indexed: 06/28/2024]
Abstract
The β-cell workload increases in the setting of insulin resistance and reduced β-cell mass, which occurs in type 2 and type 1 diabetes, respectively. The prolonged elevation of insulin production and secretion during the pathogenesis of diabetes results in β-cell ER stress. The depletion of β-cell Ca2+ER during ER stress activates the unfolded protein response, leading to β-cell dysfunction. Ca2+ER is involved in many pathways that are critical to β-cell function, such as protein processing, tuning organelle and cytosolic Ca2+ handling, and modulating lipid homeostasis. Mutations that promote β-cell ER stress and deplete Ca2+ER stores are associated with or cause diabetes (e.g., mutations in ryanodine receptors and insulin). Thus, improving β-cell Ca2+ER handling and reducing ER stress under diabetogenic conditions could preserve β-cell function and delay or prevent the onset of diabetes. This review focuses on how mechanisms that control β-cell Ca2+ER are perturbed during the pathogenesis of diabetes and contribute to β-cell failure.
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Affiliation(s)
| | - David A. Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA;
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Mann MJ, Melendez-Suchi C, Vorndran HE, Sukhoplyasova M, Flory AR, Irvine MC, Iyer AR, Guerriero CJ, Brodsky JL, Hendershot LM, Buck TM. Loss of Grp170 results in catastrophic disruption of endoplasmic reticulum function. Mol Biol Cell 2024; 35:ar59. [PMID: 38446639 PMCID: PMC11064666 DOI: 10.1091/mbc.e24-01-0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/20/2024] [Accepted: 02/29/2024] [Indexed: 03/08/2024] Open
Abstract
GRP170 (Hyou1) is required for mouse embryonic development, and its ablation in kidney nephrons leads to renal failure. Unlike most chaperones, GRP170 is the lone member of its chaperone family in the ER lumen. However, the cellular requirement for GRP170, which both binds nonnative proteins and acts as nucleotide exchange factor for BiP, is poorly understood. Here, we report on the isolation of mouse embryonic fibroblasts obtained from mice in which LoxP sites were engineered in the Hyou1 loci (Hyou1LoxP/LoxP). A doxycycline-regulated Cre recombinase was stably introduced into these cells. Induction of Cre resulted in depletion of Grp170 protein which culminated in cell death. As Grp170 levels fell we observed a portion of BiP fractionating with insoluble material, increased binding of BiP to a client with a concomitant reduction in its turnover, and reduced solubility of an aggregation-prone BiP substrate. Consistent with disrupted BiP functions, we observed reactivation of BiP and induction of the unfolded protein response (UPR) in futile attempts to provide compensatory increases in ER chaperones and folding enzymes. Together, these results provide insights into the cellular consequences of controlled Grp170 loss and provide hypotheses as to why mutations in the Hyou1 locus are linked to human disease.
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Affiliation(s)
- Melissa J. Mann
- Department of Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, TN 30105
| | - Chris Melendez-Suchi
- Department of Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, TN 30105
| | - Hannah E. Vorndran
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260
| | - Maria Sukhoplyasova
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260
| | - Ashley R. Flory
- Department of Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, TN 30105
| | - Mary Carson Irvine
- Department of Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, TN 30105
| | - Anuradha R. Iyer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260
| | | | - Jeffrey L. Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260
| | - Linda M. Hendershot
- Department of Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, TN 30105
| | - Teresa M. Buck
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260
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Muzammil K, Hooshiar MH, Varmazyar S, Omar TM, Karim MM, Aadi S, Kalavi S, Yasamineh S. Potential use of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition and prevention method in viral infection. Microb Cell Fact 2024; 23:90. [PMID: 38528584 PMCID: PMC10962113 DOI: 10.1186/s12934-024-02355-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 03/03/2024] [Indexed: 03/27/2024] Open
Abstract
Cellular lipid membranes serve as the primary barrier preventing viral infection of the host cell and provide viruses with a critical initial point of contact. Occasionally, viruses can utilize lipids as viral receptors. Viruses depend significantly on lipid rafts for infection at virtually every stage of their life cycle. The pivotal role that proprotein convertase subtilisin/kexin Type 9 (PCSK9) plays in cholesterol homeostasis and atherosclerosis, primarily by post-transcriptionally regulating hepatic low-density lipoprotein receptor (LDLR) and promoting its lysosomal degradation, has garnered increasing interest. Conversely, using therapeutic, fully humanized antibodies to block PCSK9 leads to a significant reduction in high LDL cholesterol (LDL-C) levels. The Food and Drug Administration (FDA) has approved PCSK9 inhibitors, including inclisiran (Leqvio®), alirocumab (Praluent), and evolocumab (Repatha). At present, active immunization strategies targeting PCSK9 present a compelling substitute for passive immunization through the administration of antibodies. In addition to the current inquiry into the potential therapeutic application of PCSK9 inhibition in human immunodeficiency virus (HIV)-infected patients for hyperlipidemia associated with HIV and antiretroviral therapy (ART), preclinical research suggests that PCSK9 may also play a role in inhibiting hepatitis C virus (HCV) replication. Furthermore, PCSK9 inhibition has been suggested to protect against dengue virus (DENV) potentially and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viruses. Recent evidence regarding the impact of PCSK9 on a variety of viral infections, including HCV, HIV, DENV, and SARS-CoV-2, is examined in this article. As a result, PCSK9 inhibitors and vaccines may serve as viable host therapies for viral infections, as our research indicates that PCSK9 is significantly involved in the pathogenesis of viral infections.
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Affiliation(s)
- Khursheed Muzammil
- Department of Public Health, College of Applied Medical Sciences, King Khalid University, Khamis Mushait Campus, Abha, KSA, Saudi Arabia
| | | | - Shirin Varmazyar
- Department of Medicine, Shahroud Islamic azad university of medical sciences, Sharoud, Iran
| | - Thabit Moath Omar
- Department of Medical Laboratory Technics, Al-Noor University College, Nineveh, Iraq
| | - Manal Morad Karim
- Collage of Pharmacy, National University of Science and Technology, Dhi Qar, 64001, Iraq
| | - Sadeq Aadi
- College of Dentistry, Al-Mustaqbal University, Babylon, 51001, Iraq
| | - Shaylan Kalavi
- Department of Clinical Pharmacy, faculty of pharmacy, Islamic Azad University of Medical Sciences, Tehran, Iran.
| | - Saman Yasamineh
- Young Researchers and Elite Club, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
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Ou-Yang YN, Deng FF, Wang YJ, Chen M, Yang PF, Yang Z, Tian Z. High-salt diet induces dyslipidemia through the SREBP2/PCSK9 pathway in dahl salt-sensitive rats. Biochimie 2024; 216:34-45. [PMID: 37844755 DOI: 10.1016/j.biochi.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 09/24/2023] [Accepted: 10/02/2023] [Indexed: 10/18/2023]
Abstract
A high-salt diet is known to increase serum cholesterol levels; however, the underlying mechanism of salt-induced dyslipidemia in patients with salt-sensitivity remains poorly understood. We aimed to investigate whether high-salt diet (HSD) can induce dyslipidemia and elucidate the underlying mechanism of salt-induced dyslipidemia in Dahl salt-sensitive (SS) rats. Metabolomic and biochemical analyses revealed that the consumption of an HSD (8 % NaCl) significantly increased the serum levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in SS rats. The enzyme-linked immunosorbent assay demonstrated an increase in circulating proprotein convertase subtilisin/kexin type 9 (PCSK9) levels, accompanied by a decrease in hepatic low-density lipoprotein receptor (LDLR) levels due to HSD consumption. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis revealed that HSD consumption activated sterol regulatory element-binding protein-2 (SREBP2) expression in the liver and kidney, resulting in upregulation of PCSK9 at the transcriptional level in the liver and at the translational level in the kidney, ultimately increasing circulating PCSK9 levels. The combined effects of HSD on the liver and kidney contributed to the development of hypercholesterolemia. Furthermore, an in vitro assay confirmed that high-salt exposure led to an increase in the protein expression of SREBP2 and PCSK9 secretion, thereby reducing low-density lipoprotein (LDL) uptake. This study, for the first time, shows that an HSD induces dyslipidemia through activation of the SREBP2/PCSK9 pathway, providing new insights into the prevention and treatment of dyslipidemia in patients with salt sensitivity.
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Affiliation(s)
- Ya-Nan Ou-Yang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Fen-Fen Deng
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Yun-Jia Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Meng Chen
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Peng-Fei Yang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Zhe Yang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
| | - Zhongmin Tian
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.
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10
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Mann MJ, Melendez-Suchi C, Sukhoplyasova M, Flory AR, Carson Irvine M, Iyer AR, Vorndran H, Guerriero CJ, Brodsky JL, Hendershot LM, Buck TM. Loss of Grp170 results in catastrophic disruption of endoplasmic reticulum functions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.19.563191. [PMID: 37905119 PMCID: PMC10614942 DOI: 10.1101/2023.10.19.563191] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
GRP170, a product of the Hyou1 gene, is required for mouse embryonic development, and its ablation in kidney nephrons leads to renal failure. Unlike most chaperones, GRP170 is the lone member of its chaperone family in the ER lumen. However, the cellular requirement for GRP170, which both binds non-native proteins and acts as nucleotide exchange factor for BiP, is poorly understood. Here, we report on the isolation of embryonic fibroblasts from mice in which LoxP sites were engineered in the Hyou1 loci ( Hyou1 LoxP/LoxP ). A doxycycline-regulated Cre recombinase was also stably introduced into these cells. Induction of Cre resulted in excision of Hyou1 and depletion of Grp170 protein, culminating in apoptotic cell death. As Grp170 levels fell we observed increased steady-state binding of BiP to a client, slowed degradation of a misfolded BiP substrate, and BiP accumulation in NP40-insoluble fractions. Consistent with disrupted BiP functions, we observed reactivation of BiP storage pools and induction of the unfolded protein response (UPR) in futile attempts to provide compensatory increases in ER chaperones and folding enzymes. Together, these results provide insights into the cellular consequences of controlled Grp170 loss and insights into mutations in the Hyou1 locus and human disease.
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11
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Varghese DS, Oommen D, John A, Ali BR. GRP78/BiP alleviates oxLDL-induced hepatotoxicity in familial hypercholesterolemia caused by missense variants of LDLR in a HepG2 cellular model. Lipids Health Dis 2023; 22:69. [PMID: 37248472 DOI: 10.1186/s12944-023-01835-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 05/13/2023] [Indexed: 05/31/2023] Open
Abstract
BACKGROUND AND AIMS The accumulation of misfolded proteins, encoded by genetic variants of functional genes leads to Endoplasmic Reticulum (ER) stress, which is a critical consequence in human disorders such as familial hypercholesterolemia, cardiovascular and hepatic diseases. In addition to the identification of ER stress as a contributing factor to pathogenicity, extensive studies on the role of oxidized Low-Density Lipoprotein (oxLDL) and its ill effects in expediting cardiovascular diseases and other metabolic comorbidities are well documented. However, the current understanding of its role in hepatic insults needs to be revised. This study elucidates the molecular mechanisms underlying the progression of oxLDL and ER stress-induced cytotoxicity in HepG2. METHODS HepG2 cells stably expressing wild-type Low-Density lipoprotein receptor (WT-LDLR) and missense variants of LDLR that are pathogenically associated with familial hypercholesterolemia were used as the in vitro models. The relative mRNA expression and protein profiles of ER stress sensors, inflammatory and apoptotic markers, together with cytotoxic assays and measurement of mitochondrial membrane potential, were carried out in HepG2 cells treated with 100 µg per ml oxLDL for 24 to 48 h. 1-way or 2-way ANOVA was used for statistical analyses of datasets. RESULTS ER stress responses are elicited along all three arms of the unfolded protein response (UPR), with adverse cytotoxic and inflammatory responses in oxLDL-treated conditions. Interestingly, oxLDL-treated ER-stressed HepG2 cells manifested intriguingly low expression of BiP- the master regulator of ER stress, as observed earlier by various researchers in liver biopsies of Non-Alcoholic Steatohepatitis (NASH) patients. This study shows that overexpression of BiP rescues hepatic cells from cytotoxic and inflammatory mechanisms instigated by ER stress in combination with oxLDL, along the ER and mitochondrial membrane and restores cellular homeostasis. CONCLUSION The data provide interesting leads that identify patients with familial hypercholesterolemia conditions and potentially other Endoplasmic Reticulum Associated Degradation (ERAD) diseases as highly susceptible to developing hepatic insults with molecular signatures like those manifested in Non-Alcoholic Fatty Liver Disease (NAFLD) and NASH. LIMITATIONS AND FUTURE PERSPECTIVES Although the use of HepG2 cells as the model is a major caveat of the study, the findings of this research may be used as the pilot study to expand further investigations in primary hepatocytes or iPSC- derived cellular models.
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Affiliation(s)
- Divya Saro Varghese
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Deepu Oommen
- Present Address: Indian Institute of Science, C V Raman Road, 560012, Bangalore, India
| | - Anne John
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.
- Zayed Centre for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
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12
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Ahamad S, Bhat SA. Recent Update on the Development of PCSK9 Inhibitors for Hypercholesterolemia Treatment. J Med Chem 2022; 65:15513-15539. [PMID: 36446632 DOI: 10.1021/acs.jmedchem.2c01290] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The proprotein convertase subtilisin/kexin-type 9 (PCSK9) binds to low-density lipoprotein receptors (LDLR), thereby trafficking them to lysosomes upon endocytosis and enhancing intracellular degradation to prevent their recycling. As a result, the levels of circulating LDL cholesterol (LDL-C) increase, which is a prominent risk factor for developing atherosclerotic cardiovascular diseases (ASCVD). Thus, PCSK9 has become a promising therapeutic target that offers a fertile testing ground for new drug modalities to regulate plasma LDL-C levels to prevent ASCVD. In this review, we have discussed the role of PCSK9 in lipid metabolism and briefly summarized the current clinical status of modalities targeting PCSK9. In particular, a detailed overview of peptide-based PCSK9 inhibitors is presented, which emphasizes their structural features and design, therapeutic effects on patients, and preclinical cardiovascular disease (CVD) models, along with PCSK9 modulation mechanisms. As a promising alternative to monoclonal antibodies (mAbs) for managing LDL-C, anti-PCSK9 peptides are emerging as a prospective next generation therapy.
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Affiliation(s)
- Shakir Ahamad
- Department of Chemistry, Aligarh Muslim University, Aligarh 202002, India
| | - Shahnawaz A Bhat
- Department of Zoology, Aligarh Muslim University, Aligarh 202002, India
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13
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GRP94 Inhabits the Immortalized Porcine Hepatic Stellate Cells Apoptosis under Endoplasmic Reticulum Stress through Modulating the Expression of IGF-1 and Ubiquitin. Int J Mol Sci 2022; 23:ijms232214059. [PMID: 36430538 PMCID: PMC9694842 DOI: 10.3390/ijms232214059] [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: 07/22/2022] [Revised: 10/15/2022] [Accepted: 10/25/2022] [Indexed: 11/16/2022] Open
Abstract
Endoplasmic reticulum stress (ERS) is closely related to the occurrence and progression of metabolic liver disease. The treatment targeting glucose-regulated protein 94 (GRP94) for liver disease has gotten much attention, but the specific effect of GRP94 on hepatocyte apoptosis is still unclear. So far, all the studies on GRP94 have been conducted in mice or rats, and little study has been reported on pigs, which share more similarities with humans. In this study, we used low-dose (LD) and high-dose (HD) tunicamycin (TM) to establish ERS models on piglet livers and immortalized porcine hepatic stellate cells (HSCs). On the piglet ERS model we found that ERS could significantly (p < 0.01) stimulate the secretion and synthesis of insulin-like growth factor (IGF-1), IGF-1 receptor (IGF-1R), and IGF-binding protein (IGFBP)-1 and IGFBP-3; however, with the increase in ERS degree, the effect of promoting secretion and synthesis significantly (p < 0.01) decreased. In addition, the ubiquitin protein and ubiquitination-related gene were significantly increased (p < 0.05) in the LD group compared with the vehicle group. The protein level of Active-caspase 3 was significantly increased (p < 0.01) in the HD group, however, the TUNEL staining showed there was no significant apoptosis in the piglet liver ERS model. To explore the biofunction of ER chaperone GRP94, we used shRNA to knock down the expression of GRP94 in porcine HSCs. Interestingly, on porcine HSCs, the knockdown of GRP94 significantly (p < 0.05) decreased the secretion of IGF-1, IGFBP-1 and IGFBP-3 under ERS, but had no significant effect on these under normal condition, and knockdown GRP94 had a significant (p < 0.01) effect on the UBE2E gene and ubiquitin protein from the analysis of two-way ANOVA. On porcine HSCs apoptosis, the knockdown of GRP94 increased the cell apoptosis in TUNEL staining, and the two-way ANOVA analysis shows that knockdown GRP94 had a significant (p < 0.01) effect on the protein levels of Bcl-2 and Caspase-3. For CCK-8 assay, ERS had a significant inhibitory(p < 0.05) effect on cell proliferation when treated with ERS for 24 h, and both knockdown GRP94 and ERS had a significant inhibitory(p < 0.05) effect on cell proliferation when treated with ERS for 36 h and 48 h. We concluded that GRP94 can protect the cell from ERS-induced apoptosis by promoting the IGF-1 system and ubiquitin. These results provide valuable information on the adaptive mechanisms of the liver under ERS, and could help identify vital functional genes to be applied as possible diagnostic biomarkers and treatments for diseases induced by ERS in the future.
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14
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Abstract
PURPOSE OF REVIEW Since the discovery of PCSK9 in 2003, this proprotein convertase was shown to target specific receptors for degradation in endosomes/lysosomes, including LDLR and other family members and hence to enhance the levels of circulating LDL-cholesterol (LDLc). Accordingly, inhibitors of PCSK9, including monoclonal antibodies blocking its circulating activity and siRNA silencers of its hepatic expression, are now used in clinics worldwide to treat hypercholesterolemia patients effectively and safely in combination with statins and/or ezetimibe. These powerful treatments reduce the incidence of atherosclerosis by at least 20%. Since 2008, novel targets of PCSK9 began to be defined, thereby expanding its roles beyond LDLc regulation into the realm of inflammation, pathogen infections and cellular proliferation in various cancers and associated metastases. RECENT FINDINGS Some pathogens such as dengue virus exploit the ability of PCSK9 to target the LDLR for degradation to enhance their ability to infect cells. Aside from increasing the degradation of the LDLR and its family members VLDLR, ApoER2 and LRP1, circulating PCSK9 also reduces the levels of other receptors such as CD36 (implicated in fatty acid uptake), oxidized LDLR receptor (that clears oxidized LDLc) as well as major histocompatibility class-I (MHC-I) receptors (implicated in the immune response to antigens). Thus, these novel targets provided links between PCSK9 and inflammation/atherosclerosis, viral infections and cancer/metastasis. The functional activities of PCSK9, accelerated the development of novel therapies to inhibit PCSK9 functions, including small molecular inhibitors, long-term vaccines, and possibly CRISPR-based silencing of hepatic expression of PCSK9. The future of inhibitors/silencers of PCSK9 function or expression looks bright, as these are expected to provide a modern armamentarium to treat various pathologies beyond hypercholesterolemia and its effects on atherosclerosis.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), 110 Pine Ave West, Montreal, QC, H2W 1R7, Canada.
| | - Damien Garçon
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), 110 Pine Ave West, Montreal, QC, H2W 1R7, Canada
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15
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Benito-Vicente A, Uribe KB, Larrea-Sebal A, Palacios L, Cenarro A, Calle X, Galicia-Garcia U, Jebari-Benslaiman S, Sánchez-Hernández RM, Stef M, Lambert G, Civeira F, Martín C. Leu22_Leu23 Duplication at the Signal Peptide of PCSK9 Promotes Intracellular Degradation of LDLr and Autosomal Dominant Hypercholesterolemia. Arterioscler Thromb Vasc Biol 2022; 42:e203-e216. [PMID: 35510551 DOI: 10.1161/atvbaha.122.315499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND PCSK9 (Proprotein convertase subtilisin/kexin type 9) regulates LDL-C (low-density lipoprotein cholesterol) metabolism by targeting LDLr (LDL receptor) for lysosomal degradation. PCSK9 gain-of-function variants cause autosomal dominant hypercholesterolemia by reducing LDLr levels, the D374Y variant being the most severe, while loss-of-function variants are associated with low LDL-C levels. Gain-of-function and loss-of-function activities have also been attributed to variants occurring in the PCSK9 signal peptide. Among them, L11 is a very rare PCSK9 variant that seems to increase LDL-C values in a moderate way causing mild hypercholesterolemia. METHODS Using molecular biology and biophysics methodologies, activities of L8 and L11 variants, both located in the leucine repetition stretch of the signal peptide, have been extensively characterized in vitro. RESULTS L8 variant is not associated with increased LDLr activity, whereas L11 activity is increased by ≈20% compared with wt PCSK9. The results suggest that the L11 variant reduces LDLr levels intracellularly by a process resulting from impaired cleavage of the signal peptide. This would lead to less efficient LDLr transport to the cell membrane and promote LDLr intracellular degradation. CONCLUSIONS Deletion of a leucine in the signal peptide in L8 variant does not affect PCSK9 activity, whereas the leucine duplication in the L11 variant enhances LDLr intracellular degradation. These findings highlight the importance of deep in vitro characterization of PCSK9 genetic variants to determine pathogenicity and improve clinical diagnosis and therapy of inherited familial hypercholesterolemia disease.
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Affiliation(s)
- Asier Benito-Vicente
- Biofisika Institute (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain (A.B.-V., A.L.-S., U.G.-G., S.J.-B., C.M.).,Department of Biochemistry and Molecular Biology, UPV/EHU, University of the Basque Country, Bilbao, Spain (A.B.-V., S.J.-B., C.M.)
| | - Kepa B Uribe
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Donostia-San Sebastián, Spain (K.B.U.)
| | - Asier Larrea-Sebal
- Biofisika Institute (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain (A.B.-V., A.L.-S., U.G.-G., S.J.-B., C.M.).,Fundación Biofísica Bizkaia, Leioa, Spain (A.L.-S., U.G.-G.)
| | - Lourdes Palacios
- Progenika Biopharma, a Grifols Company, Derio, Spain (L.P., M.S.)
| | - Ana Cenarro
- Lipid Unit, Hospital Universitario Miguel Servet, IIS Aragon, CIBERCV, Universidad de Zaragoza, Spain (A.C., F.C.)
| | - Xabier Calle
- Institute of Biological Phychiatry, Mental Health Services, University Hospital, Copenhagen, Denmark (X.C.)
| | - Unai Galicia-Garcia
- Biofisika Institute (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain (A.B.-V., A.L.-S., U.G.-G., S.J.-B., C.M.).,Fundación Biofísica Bizkaia, Leioa, Spain (A.L.-S., U.G.-G.)
| | - Shifa Jebari-Benslaiman
- Biofisika Institute (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain (A.B.-V., A.L.-S., U.G.-G., S.J.-B., C.M.).,Department of Biochemistry and Molecular Biology, UPV/EHU, University of the Basque Country, Bilbao, Spain (A.B.-V., S.J.-B., C.M.)
| | - Rosa M Sánchez-Hernández
- Endocrinology Department, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria and Instituto Universitario de Investigación Biomédica y Sanitaria (IUIBS) de la Universidad de Las Palmas de Gran Canaria, Spain (R.M.S.-H.)
| | - Marianne Stef
- Progenika Biopharma, a Grifols Company, Derio, Spain (L.P., M.S.)
| | - Gilles Lambert
- Inserm, Laboratoire UMR1188 DéTROI, Sainte Clotilde, France (G.L.).,Université de La Réunion, Faculté de Médecine, Saint Denis de La Réunion, France (G.L.)
| | - Fernando Civeira
- Lipid Unit, Hospital Universitario Miguel Servet, IIS Aragon, CIBERCV, Universidad de Zaragoza, Spain (A.C., F.C.)
| | - Cesar Martín
- Biofisika Institute (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain (A.B.-V., A.L.-S., U.G.-G., S.J.-B., C.M.).,Department of Biochemistry and Molecular Biology, UPV/EHU, University of the Basque Country, Bilbao, Spain (A.B.-V., S.J.-B., C.M.)
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16
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Tchéoubi SER, Akpovi CD, Coppée F, Declèves AE, Laurent S, Agbangla C, Burtea C. Molecular and cellular biology of PCSK9: impact on glucose homeostasis. J Drug Target 2022; 30:948-960. [PMID: 35723066 DOI: 10.1080/1061186x.2022.2092622] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Proprotein convertase substilisin/kexin 9 (PCSK9) inhibitors (PCSK9i) revolutionised the lipid-lowering therapy. However, a risk of type 2 diabetes mellitus (T2DM) is evoked under PCSK9i therapy. In this review, we summarise the current knowledge on the link of PCSK9 with T2DM. A significant correlation was found between PCSK9 and insulin, homeostasis model assessment (HOMA) of insulin resistance and glycated haemoglobin. PCSK9 is also involved in inflammation. PCSK9 loss-of-function variants increased T2DM risk by altering insulin secretion. Local pancreatic low PCSK9 regulates β-cell LDLR expression which in turn promotes intracellular cholesterol accumulation and hampers insulin secretion. Nevertheless, the association of PCSK9 loss-of-function variants and T2DM is inconsistent. InsLeu and R46L polymorphisms were associated with T2DM, low HOMA for β-cell function and impaired fasting glucose, while the C679X polymorphism was associated with low fasting glucose in Black South African people. Hence, we assume that the impact of these variants on glucose homeostasis may vary depending on the genetic background of the studied populations and the type of effect caused by those genetic variants on the PCSK9 protein. Accordingly, these factors should be considered when choosing a genetic variant of PCSK9 to assess the impact of long-term use of PCSK9i on glucose homeostasis.
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Affiliation(s)
- Sègbédé E R Tchéoubi
- General, Organic and Biomedical Chemistry Unit, Faculty of Medicine and Pharmacy, Research Institute for Health Sciences and Technology, University of Mons - UMONS, Mons, Belgium.,Non-Communicable Diseases and Cancer Research Unit, Laboratory of Applied Biology Research, University of Abomey-Calavi - UAC, Abomey-Calavi, Benin
| | - Casimir D Akpovi
- Non-Communicable Diseases and Cancer Research Unit, Laboratory of Applied Biology Research, University of Abomey-Calavi - UAC, Abomey-Calavi, Benin
| | - Frédérique Coppée
- Laboratory of Metabolic and Molecular Biochemistry, Faculty of Medicine and Pharmacy, Research Institute for Health Sciences and Technology, University of Mons - UMONS, Mons, Belgium
| | - Anne-Emilie Declèves
- Laboratory of Metabolic and Molecular Biochemistry, Faculty of Medicine and Pharmacy, Research Institute for Health Sciences and Technology, University of Mons - UMONS, Mons, Belgium
| | - Sophie Laurent
- General, Organic and Biomedical Chemistry Unit, Faculty of Medicine and Pharmacy, Research Institute for Health Sciences and Technology, University of Mons - UMONS, Mons, Belgium
| | - Clément Agbangla
- Laboratory of Molecular Genetics and Genome Analyzes, Faculty of Sciences and Technics, University of Abomey-Calavi - UAC, Abomey-Calavi, Benin
| | - Carmen Burtea
- General, Organic and Biomedical Chemistry Unit, Faculty of Medicine and Pharmacy, Research Institute for Health Sciences and Technology, University of Mons - UMONS, Mons, Belgium
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17
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Abstract
This article reviews the discovery of PCSK9, its structure-function characteristics, and its presently known and proposed novel biological functions. The major critical function of PCSK9 deduced from human and mouse studies, as well as cellular and structural analyses, is its role in increasing the levels of circulating low-density lipoprotein (LDL)-cholesterol (LDLc), via its ability to enhance the sorting and escort of the cell surface LDL receptor (LDLR) to lysosomes. This implicates the binding of the catalytic domain of PCSK9 to the EGF-A domain of the LDLR. This also requires the presence of the C-terminal Cys/His-rich domain, its binding to the secreted cytosolic cyclase associated protein 1, and possibly another membrane-bound "protein X". Curiously, in PCSK9-deficient mice, an alternative to the downregulation of the surface levels of the LDLR by PCSK9 is taking place in the liver of female mice in a 17β-estradiol-dependent manner by still an unknown mechanism. Recent studies have extended our understanding of the biological functions of PCSK9, namely its implication in septic shock, vascular inflammation, viral infections (Dengue; SARS-CoV-2) or immune checkpoint modulation in cancer via the regulation of the cell surface levels of the T-cell receptor and MHC-I, which govern the antitumoral activity of CD8+ T cells. Because PCSK9 inhibition may be advantageous in these processes, the availability of injectable safe PCSK9 inhibitors that reduces by 50% to 60% LDLc above the effect of statins is highly valuable. Indeed, injectable PCSK9 monoclonal antibody or small interfering RNA could be added to current immunotherapies in cancer/metastasis.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), Montreal, QC, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), Montreal, QC, Canada
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18
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Lebeau PF, Platko K, Byun JH, Makda Y, Austin RC. The Emerging Roles of Intracellular PCSK9 and Their Implications in Endoplasmic Reticulum Stress and Metabolic Diseases. Metabolites 2022; 12:metabo12030215. [PMID: 35323658 PMCID: PMC8954296 DOI: 10.3390/metabo12030215] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/20/2022] [Accepted: 02/25/2022] [Indexed: 02/04/2023] Open
Abstract
The importance of the proprotein convertase subtilisin/kexin type-9 (PCSK9) gene was quickly recognized by the scientific community as the third locus for familial hypercholesterolemia. By promoting the degradation of the low-density lipoprotein receptor (LDLR), secreted PCSK9 protein plays a vital role in the regulation of circulating cholesterol levels and cardiovascular disease risk. For this reason, the majority of published works have focused on the secreted form of PCSK9 since its initial characterization in 2003. In recent years, however, PCSK9 has been shown to play roles in a variety of cellular pathways and disease contexts in LDLR-dependent and -independent manners. This article examines the current body of literature that uncovers the intracellular and LDLR-independent roles of PCSK9 and also explores the many downstream implications in metabolic diseases.
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19
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Clark LE, Clark SA, Lin C, Liu J, Coscia A, Nabel KG, Yang P, Neel DV, Lee H, Brusic V, Stryapunina I, Plante KS, Ahmed AA, Catteruccia F, Young-Pearse TL, Chiu IM, Llopis PM, Weaver SC, Abraham J. VLDLR and ApoER2 are receptors for multiple alphaviruses. Nature 2021; 602:475-480. [PMID: 34929721 PMCID: PMC8808280 DOI: 10.1038/s41586-021-04326-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 12/09/2021] [Indexed: 12/03/2022]
Abstract
Alphaviruses, like many other arthropod-borne viruses, infect vertebrate species and insect vectors separated by hundreds of millions of years of evolutionary history. Entry into evolutionarily divergent host cells can be accomplished by recognition of different cellular receptors in different species, or by binding to receptors that are highly conserved across species. Although multiple alphavirus receptors have been described1–3, most are not shared among vertebrate and invertebrate hosts. Here we identify the very low-density lipoprotein receptor (VLDLR) as a receptor for the prototypic alphavirus Semliki forest virus. We show that the E2 and E1 glycoproteins (E2–E1) of Semliki forest virus, eastern equine encephalitis virus and Sindbis virus interact with the ligand-binding domains (LBDs) of VLDLR and apolipoprotein E receptor 2 (ApoER2), two closely related receptors. Ectopic expression of either protein facilitates cellular attachment, and internalization of virus-like particles, a VLDLR LBD–Fc fusion protein or a ligand-binding antagonist block Semliki forest virus E2–E1-mediated infection of human and mouse neurons in culture. The administration of a VLDLR LBD–Fc fusion protein has protective activity against rapidly fatal Semliki forest virus infection in mouse neonates. We further show that invertebrate receptor orthologues from mosquitoes and worms can serve as functional alphavirus receptors. We propose that the ability of some alphaviruses to infect a wide range of hosts is a result of their engagement of evolutionarily conserved lipoprotein receptors and contributes to their pathogenesis. Studies using viral coat glycoproteins show that alphaviruses can enter cells via the very low-density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), members of an evolutionarily conserved family of lipoprotein receptors.
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Affiliation(s)
- Lars E Clark
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Sarah A Clark
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - ChieYu Lin
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jianying Liu
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Adrian Coscia
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Katherine G Nabel
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Pan Yang
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Dylan V Neel
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Hyo Lee
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Vesna Brusic
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Iryna Stryapunina
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Kenneth S Plante
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.,World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA
| | - Asim A Ahmed
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
| | - Flaminia Catteruccia
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Isaac M Chiu
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Paula Montero Llopis
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.,MicRoN Core, Harvard Medical School, Boston, MA, USA
| | - Scott C Weaver
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.,World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA
| | - Jonathan Abraham
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA. .,Department of Medicine, Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA, USA. .,Broad Institute of Harvard and MIT, Cambridge, MA, USA.
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20
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Ganaie SS, Schwarz MM, McMillen CM, Price DA, Feng AX, Albe JR, Wang W, Miersch S, Orvedahl A, Cole AR, Sentmanat MF, Mishra N, Boyles DA, Koenig ZT, Kujawa MR, Demers MA, Hoehl RM, Moyle AB, Wagner ND, Stubbs SH, Cardarelli L, Teyra J, McElroy A, Gross ML, Whelan SPJ, Doench J, Cui X, Brett TJ, Sidhu SS, Virgin HW, Egawa T, Leung DW, Amarasinghe GK, Hartman AL. Lrp1 is a host entry factor for Rift Valley fever virus. Cell 2021; 184:5163-5178.e24. [PMID: 34559985 DOI: 10.1016/j.cell.2021.09.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 04/29/2021] [Accepted: 09/01/2021] [Indexed: 12/26/2022]
Abstract
Rift Valley fever virus (RVFV) is a zoonotic pathogen with pandemic potential. RVFV entry is mediated by the viral glycoprotein (Gn), but host entry factors remain poorly defined. Our genome-wide CRISPR screen identified low-density lipoprotein receptor-related protein 1 (mouse Lrp1/human LRP1), heat shock protein (Grp94), and receptor-associated protein (RAP) as critical host factors for RVFV infection. RVFV Gn directly binds to specific Lrp1 clusters and is glycosylation independent. Exogenous addition of murine RAP domain 3 (mRAPD3) and anti-Lrp1 antibodies neutralizes RVFV infection in taxonomically diverse cell lines. Mice treated with mRAPD3 and infected with pathogenic RVFV are protected from disease and death. A mutant mRAPD3 that binds Lrp1 weakly failed to protect from RVFV infection. Together, these data support Lrp1 as a host entry factor for RVFV infection and define a new target to limit RVFV infections.
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Affiliation(s)
- Safder S Ganaie
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Madeline M Schwarz
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Cynthia M McMillen
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - David A Price
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Annie X Feng
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Joseph R Albe
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Wenjie Wang
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Shane Miersch
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Anthony Orvedahl
- Department of Pediatrics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Aidan R Cole
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Monica F Sentmanat
- Genome Engineering and iPSC Center (GEiC), Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Nawneet Mishra
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Devin A Boyles
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Zachary T Koenig
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael R Kujawa
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Matthew A Demers
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ryan M Hoehl
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Austin B Moyle
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicole D Wagner
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Sarah H Stubbs
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Lia Cardarelli
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Joan Teyra
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Anita McElroy
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pediatrics, Division of Pediatric Infectious Disease, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Sean P J Whelan
- Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO, USA
| | - John Doench
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Xiaoxia Cui
- Genome Engineering and iPSC Center (GEiC), Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Tom J Brett
- Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Sachdev S Sidhu
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Herbert W Virgin
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA; Current address: Vir Biotechnology, San Francisco, CA, USA
| | - Takeshi Egawa
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA; Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
| | - Amy L Hartman
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
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21
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Rogers MA, Hutcheson JD, Okui T, Goettsch C, Singh SA, Halu A, Schlotter F, Higashi H, Wang L, Whelan MC, Mlynarchik AK, Daugherty A, Nomura M, Aikawa M, Aikawa E. Dynamin-related protein 1 inhibition reduces hepatic PCSK9 secretion. Cardiovasc Res 2021; 117:2340-2353. [PMID: 33523181 PMCID: PMC8479802 DOI: 10.1093/cvr/cvab034] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/29/2020] [Accepted: 01/27/2021] [Indexed: 12/26/2022] Open
Abstract
AIMS Proteostasis maintains protein homeostasis and participates in regulating critical cardiometabolic disease risk factors including proprotein convertase subtilisin/kexin type 9 (PCSK9). Endoplasmic reticulum (ER) remodeling through release and incorporation of trafficking vesicles mediates protein secretion and degradation. We hypothesized that ER remodeling that drives mitochondrial fission participates in cardiometabolic proteostasis. METHODS AND RESULTS We used in vitro and in vivo hepatocyte inhibition of a protein involved in mitochondrial fission, dynamin-related protein 1 (DRP1). Here, we show that DRP1 promotes remodeling of select ER microdomains by tethering vesicles at ER. A DRP1 inhibitor, mitochondrial division inhibitor 1 (mdivi-1) reduced ER localization of a DRP1 receptor, mitochondrial fission factor, suppressing ER remodeling-driven mitochondrial fission, autophagy, and increased mitochondrial calcium buffering and PCSK9 proteasomal degradation. DRP1 inhibition by CRISPR/Cas9 deletion or mdivi-1 alone or in combination with statin incubation in human hepatocytes and hepatocyte-specific Drp1-deficiency in mice reduced PCSK9 secretion (-78.5%). In HepG2 cells, mdivi-1 increased low-density lipoprotein receptor via c-Jun transcription and reduced PCSK9 mRNA levels via suppressed sterol regulatory binding protein-1c. Additionally, mdivi-1 reduced macrophage burden, oxidative stress, and advanced calcified atherosclerotic plaque in aortic roots of diabetic Apoe-deficient mice and inflammatory cytokine production in human macrophages. CONCLUSIONS We propose a novel tethering function of DRP1 beyond its established fission function, with DRP1-mediated ER remodeling likely contributing to ER constriction of mitochondria that drives mitochondrial fission. We report that DRP1-driven remodeling of select ER micro-domains may critically regulate hepatic proteostasis and identify mdivi-1 as a novel small molecule PCSK9 inhibitor.
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Affiliation(s)
- Maximillian A Rogers
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Joshua D Hutcheson
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Takehito Okui
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Claudia Goettsch
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sasha A Singh
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Arda Halu
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Florian Schlotter
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Hideyuki Higashi
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lixiang Wang
- Department of Medical Biochemistry, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Mary C Whelan
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew K Mlynarchik
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Alan Daugherty
- Saha Cardiovascular Research Center and Department of Physiology, University of Kentucky, Lexington, KY 40536, USA
| | - Masatoshi Nomura
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Masanori Aikawa
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Excellence in Vascular Biology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Elena Aikawa
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Excellence in Vascular Biology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Human Pathology, Sechenov First Moscow State Medical University, Moscow 119992, Russia
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22
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Lebeau PF, Wassef H, Byun JH, Platko K, Ason B, Jackson S, Dobroff J, Shetterly S, Richards WG, Al-Hashimi AA, Won KD, Mbikay M, Prat A, Tang A, Paré G, Pasqualini R, Seidah NG, Arap W, Chrétien M, Austin RC. The loss-of-function PCSK9Q152H variant increases ER chaperones GRP78 and GRP94 and protects against liver injury. J Clin Invest 2021; 131:128650. [PMID: 33211673 DOI: 10.1172/jci128650] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 11/03/2020] [Indexed: 12/11/2022] Open
Abstract
Individuals harboring the loss-of-function (LOF) proprotein convertase subtilisin/kexin type 9 Gln152His variation (PCSK9Q152H) have low circulating low-density lipoprotein cholesterol levels and are therefore protected against cardiovascular disease (CVD). This uncleavable form of proPCSK9, however, is retained in the endoplasmic reticulum (ER) of liver hepatocytes, where it would be expected to contribute to ER storage disease (ERSD), a heritable condition known to cause systemic ER stress and liver injury. Here, we examined liver function in members of several French-Canadian families known to carry the PCSK9Q152H variation. We report that PCSK9Q152H carriers exhibited marked hypocholesterolemia and normal liver function despite their lifelong state of ER PCSK9 retention. Mechanistically, hepatic overexpression of PCSK9Q152H using adeno-associated viruses in male mice greatly increased the stability of key ER stress-response chaperones in liver hepatocytes and unexpectedly protected against ER stress and liver injury rather than inducing them. Our findings show that ER retention of PCSK9 not only reduced CVD risk in patients but may also protect against ERSD and other ER stress-driven conditions of the liver. In summary, we have uncovered a cochaperone function for PCSK9Q152H that explains its hepatoprotective effects and generated a translational mouse model for further mechanistic insights into this clinically relevant LOF PCSK9 variant.
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Affiliation(s)
- Paul F Lebeau
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
| | - Hanny Wassef
- Laboratory of Functional Endoproteolysis, Clinical Research Institute of Montreal, affiliated with the University of Montreal, Montreal, Quebec, Canada
| | - Jae Hyun Byun
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
| | - Khrystyna Platko
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
| | - Brandon Ason
- Cardiometabolic Disorders, Amgen Research Inc., South San Francisco, California, USA
| | - Simon Jackson
- Cardiometabolic Disorders, Amgen Research Inc., South San Francisco, California, USA
| | | | - Susan Shetterly
- Cardiometabolic Disorders, Amgen Research Inc., South San Francisco, California, USA
| | | | - Ali A Al-Hashimi
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
| | - Kevin Doyoon Won
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
| | - Majambu Mbikay
- Laboratory of Functional Endoproteolysis, Clinical Research Institute of Montreal, affiliated with the University of Montreal, Montreal, Quebec, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, affiliated with the University of Montreal, Montreal, Quebec, Canada
| | - An Tang
- Department of Radiology at the Centre Hospitalier Universitaire de Montréal, University of Montreal, Montreal, Quebec, Canada
| | - Guillaume Paré
- Population Health Research Institute and Departments of Medicine, Epidemiology, and Pathology, McMaster University, Hamilton, Ontario, Canada
| | | | - Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, affiliated with the University of Montreal, Montreal, Quebec, Canada
| | - Wadih Arap
- Division of Hematology/Oncology, Department of Medicine, Rutgers New Jersey Medical School and Rutgers Cancer Institute of New Jersey, Newark, New Jersey, USA
| | - Michel Chrétien
- Laboratory of Functional Endoproteolysis, Clinical Research Institute of Montreal, affiliated with the University of Montreal, Montreal, Quebec, Canada
| | - Richard C Austin
- Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario, Canada
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23
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Ren H, Yao W, Wei Q, Zhang J, Zhao B, Miao J. Identification of a new autophagy inhibitor targeting lipid droplets in vascular endothelial cells. Biochem Biophys Res Commun 2021; 571:195-200. [PMID: 34330064 DOI: 10.1016/j.bbrc.2021.07.078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 01/06/2023]
Abstract
Autophagy of vascular endothelial cells (VECs) plays an important role in maintaining vascular homeostasis. Lipid droplets (LDs) are organelles that can be formed in response to various stimuli, including excessive lipid or various stresses. LDs sequester toxic lipids, thereby preventing lipotoxic cell damage and have a complex relationship with autophagy. In the previous study, we identified a novel Grp94 inhibitor HCP1 inhibited apoptosis in VECs. Here we found that HCP1 targeted LDs and promoted the accumulation of LDs in VECs. Our results showed that HCP1 upregulated the protein levels of autophagy-related proteins. We demonstrated that HCP1 upregulated the number of LDs and suppressed autophagy by inhibiting Grp94. Therefore, we provided HCP1 as a new VECs autophagy inhibitor targeting LDs, which might be a potential compound in the treatment of VECs autophagy related vascular diseases.
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Affiliation(s)
- Hui Ren
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Qingdao, 266237, PR China
| | - Wen Yao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Qingdao, 266237, PR China
| | - Qun Wei
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Qingdao, 266237, PR China; Department of Otorhinolaryngology, Qilu Hospital of Shandong University, NHC Key Laboratory of Otorhinolaryngology (Shandong University), Jinan, 250012, Shandong, PR China
| | - Jun Zhang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Qingdao, 266237, PR China
| | - BaoXiang Zhao
- Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, PR China
| | - JunYing Miao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Qingdao, 266237, PR China.
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24
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PCSK9 is not secreted from mature differentiated intestinal cells. J Lipid Res 2021; 62:100096. [PMID: 34280453 PMCID: PMC8436166 DOI: 10.1016/j.jlr.2021.100096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 12/01/2022] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes lysosomal degradation of the LDL receptor and is a key regulator of cholesterol metabolism. After the liver, the small intestine is the second organ that highly expresses PCSK9. However, the small intestine's ability to secrete PCSK9 remains a matter of debate. While liver-specific PCSK9-deficient mice present no PCSK9 in systemic blood, human intestinal Caco-2 cells can actively secrete PCSK9. This raises the possibility for active intestinal secretion via the portal blood. Here, we aimed to determine whether enterocytes can secrete PCSK9 using in vitro, ex vivo, and in vivo approaches. We first observed that PCSK9 secretion from Caco-2 cells was biphasic and dependent on Caco-2 maturation status. Transcriptional analysis suggested that this transient reduction in PCSK9 secretion might be due to loss of SREBP2-mediated transcription of PCSK9. Consistently, PCSK9 secretion was not detected ex vivo in human or mouse intestinal biopsies mounted in Ussing chambers. Finally, direct comparison of systemic versus portal blood PCSK9 concentrations in WT or liver-specific PCSK9-deficient mice confirmed the inability of the small intestine to secrete PCSK9 into the portal compartment. Altogether, our data demonstrate that mature enterocytes do not secrete PCSK9 and reinforce the central role of the liver in the regulation of the concentration of circulating PCSK9 and consequently of cellular LDL receptors.
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25
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Burnap SA, Mayr M. DRP1-a Novel Regulator of PCSK9 Secretion and Degradation. Cardiovasc Res 2021; 117:2289-2290. [PMID: 34264313 DOI: 10.1093/cvr/cvab227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sean A Burnap
- King's College London British Heart Foundation Centre, School of Cardiovascular Medicine and Sciences, London, United Kingdom
| | - Manuel Mayr
- King's College London British Heart Foundation Centre, School of Cardiovascular Medicine and Sciences, London, United Kingdom
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26
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Barale C, Melchionda E, Morotti A, Russo I. PCSK9 Biology and Its Role in Atherothrombosis. Int J Mol Sci 2021; 22:ijms22115880. [PMID: 34070931 PMCID: PMC8198903 DOI: 10.3390/ijms22115880] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/11/2022] Open
Abstract
It is now about 20 years since the first case of a gain-of-function mutation involving the as-yet-unknown actor in cholesterol homeostasis, proprotein convertase subtilisin/kexin type 9 (PCSK9), was described. It was soon clear that this protein would have been of huge scientific and clinical value as a therapeutic strategy for dyslipidemia and atherosclerosis-associated cardiovascular disease (CVD) management. Indeed, PCSK9 is a serine protease belonging to the proprotein convertase family, mainly produced by the liver, and essential for metabolism of LDL particles by inhibiting LDL receptor (LDLR) recirculation to the cell surface with the consequent upregulation of LDLR-dependent LDL-C levels. Beyond its effects on LDL metabolism, several studies revealed the existence of additional roles of PCSK9 in different stages of atherosclerosis, also for its ability to target other members of the LDLR family. PCSK9 from plasma and vascular cells can contribute to the development of atherosclerotic plaque and thrombosis by promoting platelet activation, leukocyte recruitment and clot formation, also through mechanisms not related to systemic lipid changes. These results further supported the value for the potential cardiovascular benefits of therapies based on PCSK9 inhibition. Actually, the passive immunization with anti-PCSK9 antibodies, evolocumab and alirocumab, is shown to be effective in dramatically reducing the LDL-C levels and attenuating CVD. While monoclonal antibodies sequester circulating PCSK9, inclisiran, a small interfering RNA, is a new drug that inhibits PCSK9 synthesis with the important advantage, compared with PCSK9 mAbs, to preserve its pharmacodynamic effects when administrated every 6 months. Here, we will focus on the major understandings related to PCSK9, from its discovery to its role in lipoprotein metabolism, involvement in atherothrombosis and a brief excursus on approved current therapies used to inhibit its action.
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MESH Headings
- Antibodies, Monoclonal, Humanized/therapeutic use
- Atherosclerosis/drug therapy
- Atherosclerosis/enzymology
- Atherosclerosis/genetics
- Atherosclerosis/pathology
- Blood Platelets/drug effects
- Blood Platelets/enzymology
- Blood Platelets/pathology
- Cholesterol, LDL/antagonists & inhibitors
- Cholesterol, LDL/metabolism
- Dyslipidemias/drug therapy
- Dyslipidemias/enzymology
- Dyslipidemias/genetics
- Dyslipidemias/pathology
- Fibrinolytic Agents/therapeutic use
- Gene Expression Regulation
- Humans
- Hypolipidemic Agents/therapeutic use
- Lipid Metabolism/drug effects
- Lipid Metabolism/genetics
- PCSK9 Inhibitors
- Plaque, Atherosclerotic/drug therapy
- Plaque, Atherosclerotic/enzymology
- Plaque, Atherosclerotic/genetics
- Plaque, Atherosclerotic/pathology
- Platelet Activation/drug effects
- Proprotein Convertase 9/biosynthesis
- Proprotein Convertase 9/genetics
- RNA, Small Interfering/therapeutic use
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Signal Transduction
- Thrombosis/enzymology
- Thrombosis/genetics
- Thrombosis/pathology
- Thrombosis/prevention & control
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27
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Ramin-Mangata S, Thedrez A, Nativel B, Diotel N, Blanchard V, Wargny M, Aguesse A, Billon-Crossouard S, Vindis C, Le May C, Hulin P, Armanet M, Gmyr V, Pattou F, Croyal M, Meilhac O, Nobécourt E, Cariou B, Lambert G. Effects of proprotein convertase subtilisin kexin type 9 modulation in human pancreatic beta cells function. Atherosclerosis 2021; 326:47-55. [PMID: 33933263 DOI: 10.1016/j.atherosclerosis.2021.03.044] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/09/2021] [Accepted: 03/30/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND AND AIMS Proprotein Convertase Subtilisin Kexin Type 9 (PCSK9) is an endogenous inhibitor of the LDL receptor (LDLR). Mendelian randomization studies suggest that PCSK9 deficiency increases diabetes risk, but the underlying mechanisms remain unknown. The aim of our study was to investigate whether PCSK9 or its inhibition may modulate beta cell function. METHODS We assessed PCSK9 and insulin colocalization in human pancreatic sections by epifluorescent and confocal microscopy. We also investigated the expression and the function of PCSK9 in the human EndoC-βH1 beta cell line, by ELISA and flow cytometry, respectively. PCSK9 was inhibited with Alirocumab or siRNA. LDLR expression and LDL uptake were assessed by flow cytometry. RESULTS PCSK9 was expressed and secreted from beta cells isolated from human pancreas as well as from EndoC-βH1 cells. PCSK9 secretion was enhanced by statin treatment. Recombinant PCSK9 decreased LDLR abundance at the surface of these cells, an effect abrogated by Alirocumab. Alirocumab as well as PCSK9 silencing increased LDLR expression at the surface of EndoC-βH1 cells. Neither exogenous PCSK9, nor Alirocumab, nor PCSK9 silencing significantly altered glucose-stimulated insulin secretion (GSIS) from these cells. High-low density lipoproteins (LDL) concentrations decreased GSIS, but the addition of PCSK9 or its inhibition did not modulate this phenomenon. CONCLUSIONS While PCSK9 regulates LDLR abundance in beta cells, inhibition of exogenous or endogenous PCSK9 does not appear to significantly impact insulin secretion. This is reassuring for the safety of PCSK9 inhibitors in terms of beta cell function.
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Affiliation(s)
| | - Aurélie Thedrez
- Université de Nantes, CRNH Ouest, Inra UMR 1280 PhAN, Nantes, France; L'institut du Thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France
| | - Brice Nativel
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France
| | - Nicolas Diotel
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France
| | - Valentin Blanchard
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France
| | - Matthieu Wargny
- L'institut du Thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France; CHU Nantes, INSERM, CIC 1413, Pôle Hospitalo-Universitaire 11: Santé Publique, Clinique des Données, Nantes, F-44093, France
| | - Audrey Aguesse
- Université de Nantes, CRNH Ouest, Inra UMR 1280 PhAN, Nantes, France
| | | | | | - Cédric Le May
- L'institut du Thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France
| | - Philippe Hulin
- Université de Nantes, CHU de Nantes, Inserm UMS 016, Cnrs UMS 3556, Structure Fédérative de Recherche François Bonamy, Micropicell Facility, Nantes, France
| | - Mathieu Armanet
- Cell Therapy Unit, Hôpital Saint Louis, AP-HP, Université Paris Diderot, Paris, France
| | - Valery Gmyr
- European Genomic Institute for Diabetes, Inserm UMR 1190 Translational Research for Diabetes, University of Lille 2, Lille, France
| | - François Pattou
- European Genomic Institute for Diabetes, Inserm UMR 1190 Translational Research for Diabetes, University of Lille 2, Lille, France; Lille University Hospital, Lille, France
| | - Mikaël Croyal
- Université de Nantes, CRNH Ouest, Inra UMR 1280 PhAN, Nantes, France
| | - Olivier Meilhac
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France
| | - Estelle Nobécourt
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France; CHU de La Réunion, Service d'Endocrinologie Nutrition, Saint-Pierre, France
| | - Bertrand Cariou
- L'institut du Thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France
| | - Gilles Lambert
- Université de La Réunion, Inserm UMR 1188 DéTROI, Sainte Clotilde, France.
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28
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de Boer JF, de Vries HD, Palmiotti A, Li R, Doestzada M, Hoogerland JA, Fu J, La Rose AM, Westerterp M, Mulder NL, Hovingh MV, Koehorst M, Kloosterhuis NJ, Wolters JC, Bloks VW, Haas JT, Dombrowicz D, Staels B, van de Sluis B, Kuipers F. Cholangiopathy and Biliary Fibrosis in Cyp2c70-Deficient Mice Are Fully Reversed by Ursodeoxycholic Acid. Cell Mol Gastroenterol Hepatol 2020; 11:1045-1069. [PMID: 33309945 PMCID: PMC7898074 DOI: 10.1016/j.jcmgh.2020.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/04/2020] [Accepted: 12/04/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Bile acids (BAs) aid intestinal fat absorption and exert systemic actions by receptor-mediated signaling. BA receptors have been identified as drug targets for liver diseases. Yet, differences in BA metabolism between humans and mice hamper translation of pre-clinical outcomes. Cyp2c70-ablation in mice prevents synthesis of mouse/rat-specific muricholic acids (MCAs), but potential (patho)physiological consequences of their absence are unknown. We therefore assessed age- and gender-dependent effects of Cyp2c70-deficiency in mice. METHODS The consequences of Cyp2c70-deficiency were assessed in male and female mice at different ages. RESULTS Cyp2c70-/- mice were devoid of MCAs and showed high abundances of chenodeoxycholic and lithocholic acids. Cyp2c70-deficiency profoundly impacted microbiome composition. Bile flow and biliary BA secretion were normal in Cyp2c70-/- mice of both sexes. Yet, the pathophysiological consequences of Cyp2c70-deficiency differed considerably between sexes. Three-week old male Cyp2c70-/- mice showed high plasma BAs and transaminases, which spontaneously decreased thereafter to near-normal levels. Only mild ductular reactions were observed in male Cyp2c70-/- mice up to 8 months of age. In female Cyp2c70-/- mice, plasma BAs and transaminases remained substantially elevated with age, gut barrier function was impaired and bridging fibrosis was observed at advanced age. Addition of 0.1% ursodeoxycholic acid to the diet fully normalized hepatic and intestinal functions in female Cyp2c70-/- mice. CONCLUSION Cyp2c70-/- mice show transient neonatal cholestasis and develop cholangiopathic features that progress to bridging fibrosis in females only. These consequences of Cyp2c70-deficiency are restored by treatment with UDCA, indicating a role of BA hydrophobicity in disease development.
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Affiliation(s)
- Jan Freark de Boer
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands; Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
| | - Hilde D de Vries
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; University of Groningen, Campus Fryslân, Leeuwarden, the Netherlands
| | - Anna Palmiotti
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Rumei Li
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Marwah Doestzada
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands; Department of Genetics University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Joanne A Hoogerland
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur Lille, U1011-EGID, F-59000 Lille, France
| | - Jingyuan Fu
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands; Department of Genetics University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Anouk M La Rose
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Marit Westerterp
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Niels L Mulder
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Milaine V Hovingh
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Martijn Koehorst
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Niels J Kloosterhuis
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Justina C Wolters
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Vincent W Bloks
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands
| | - Joel T Haas
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur Lille, U1011-EGID, F-59000 Lille, France
| | - David Dombrowicz
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur Lille, U1011-EGID, F-59000 Lille, France
| | - Bart Staels
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur Lille, U1011-EGID, F-59000 Lille, France
| | - Bart van de Sluis
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands; iPSC/CRISPR Center Groningen, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Folkert Kuipers
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, the Netherlands; Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
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29
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Roger C, Buch C, Muller T, Leemput J, Demizieux L, Passilly-Degrace P, Cinar R, Iyer MR, Kunos G, Vergès B, Degrace P, Jourdan T. Simultaneous Inhibition of Peripheral CB1R and iNOS Mitigates Obesity-Related Dyslipidemia Through Distinct Mechanisms. Diabetes 2020; 69:2120-2132. [PMID: 32680936 PMCID: PMC7506827 DOI: 10.2337/db20-0078] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 07/05/2020] [Indexed: 12/17/2022]
Abstract
Diabetic dyslipidemia, characterized by increased plasma triglycerides and decreased HDL cholesterol levels, is a major factor contributing to nonalcoholic steatohepatitis and cardiovascular risk in type 2 diabetes. Activation of the cannabinoid-1 receptor (CB1R) and activation of inducible nitric oxide synthase (iNOS) are associated with nonalcoholic steatohepatitis progression. Here, we tested whether dual-targeting inhibition of hepatic CB1R and iNOS improves diabetic dyslipidemia in mice with diet-induced obesity (DIO mice). DIO mice were treated for 14 days with (S)-MRI-1867, a peripherally restricted hybrid inhibitor of CB1R and iNOS. (R)-MRI-1867, the CB1R-inactive stereoisomer that retains iNOS inhibitory activity, and JD-5037, a peripherally restricted CB1R antagonist, were used to assess the relative contribution of the two targets to the effects of (S)-MRI-1867. (S)-MRI-1867 reduced hepatic steatosis and the rate of hepatic VLDL secretion, upregulated hepatic LDLR expression, and reduced the circulating levels of proprotein convertase subtilisin/kexin type 9 (PCSK9). The decrease in VLDL secretion could be attributed to CB1R blockade, while the reduction of PCSK9 levels and the related increase in LDLR resulted from iNOS inhibition via an mTOR complex 1-dependent mechanism. In conclusion, this approach based on the concomitant inhibition of CB1R and iNOS represents a promising therapeutic strategy for the treatment of dyslipidemia.
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Affiliation(s)
- Célia Roger
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Chloé Buch
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Tania Muller
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Julia Leemput
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Laurent Demizieux
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Patricia Passilly-Degrace
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD
| | - Malliga R Iyer
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD
| | - George Kunos
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD
| | - Bruno Vergès
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Pascal Degrace
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
| | - Tony Jourdan
- INSERM Lipids, Nutrition, Cancer (LNC) UMR1231, Team PADYS, University of Burgundy and Franche-Comté, Dijon, France
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30
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Oommen D, Kizhakkedath P, Jawabri AA, Varghese DS, Ali BR. Proteostasis Regulation in the Endoplasmic Reticulum: An Emerging Theme in the Molecular Pathology and Therapeutic Management of Familial Hypercholesterolemia. Front Genet 2020; 11:570355. [PMID: 33173538 PMCID: PMC7538668 DOI: 10.3389/fgene.2020.570355] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/31/2020] [Indexed: 02/05/2023] Open
Abstract
Familial hypercholesterolemia (FH) is an autosomal genetic disease characterized by high serum low-density lipoprotein (LDL) content leading to premature coronary artery disease. The main genetic and molecular causes of FH are mutations in low-density lipoprotein receptor gene (LDLR) resulting in the non-clearance of LDL from the blood by hepatocytes and consequently the formation of plaques. LDLR is synthesized and glycosylated in the endoplasmic reticulum (ER) and then transported to the plasma membrane via Golgi. It is estimated that more than 50% of reported FH-causing mutations in LDLR result in misfolded proteins that are transport-defective and hence retained in ER. ER accumulation of misfolded proteins causes ER-stress and activates unfolded protein response (UPR). UPR aids protein folding, blocks further protein synthesis, and eliminates misfolded proteins via ER-associated degradation (ERAD) to alleviate ER stress. Various studies demonstrated that ER-retained LDLR mutants are subjected to ERAD. Interestingly, chemical chaperones and genetic or pharmacological inhibition of ERAD have been reported to rescue the transport defective mutant LDLR alleles from ERAD and restore their ER-Golgi transport resulting in the expression of functional plasma membrane LDLR. This suggests the possibility of pharmacological modulation of proteostasis in the ER as a therapeutic strategy for FH. In this review, we picture a detailed analysis of UPR and the ERAD processes activated by ER-retained LDLR mutants associated with FH. In addition, we discuss and critically evaluate the potential role of chemical chaperones and ERAD modulators in the therapeutic management of FH.
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Affiliation(s)
- Deepu Oommen
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Praseetha Kizhakkedath
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Aseel A Jawabri
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Divya Saro Varghese
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.,Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.,Zayed Center for Health Sciences, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
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31
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Emma MR, Giannitrapani L, Cabibi D, Porcasi R, Pantuso G, Augello G, Giglio RV, Re NL, Capitano AR, Montalto G, Soresi M, Cervello M. Hepatic and circulating levels of PCSK9 in morbidly obese patients: Relation with severity of liver steatosis. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158792. [PMID: 32777481 DOI: 10.1016/j.bbalip.2020.158792] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/03/2020] [Accepted: 08/03/2020] [Indexed: 02/07/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is becoming the main cause of liver disease in Western countries, especially in morbidly obese patients (MOPs). The proprotein convertase subtilisin/kexin type 9 (PCSK9) has been recently studied because of its possible involvement in the pathogenesis of NAFLD, but its role, at least in MOPs, is still controversial. The aim of this study was to clarify the correlation between the circulating levels of the PCSK9 protein (cPCSK9) and its hepatic expression with the severity of liver damage in a population of MOPs with NAFLD undergoing bariatric surgery. PCSK9 mRNA was positively correlated with FASN, PPARγ and PPARα mRNAs, while no significant differences were found in PCSK9 mRNA expression in relation to the severity of liver steatosis, lobular inflammation and hepatocellular ballooning. In addition, hepatic PCSK9 protein expression levels were not related to histological parameters of lobular inflammation and hepatocyte ballooning, decreased significantly only in relation to the severity of hepatic steatosis, and were inversely correlated with ALT and AST serum levels. cPCSK9 levels in the whole population were associated with the severity of hepatic steatosis and were positively correlated to total cholesterol levels. In multivariate analysis, cPCSK9 levels were associated with age, total cholesterol and HbA1c. In conclusion, in MOPs our findings support a role for PCSK9 in liver fat accumulation, but not in liver damage progression, and confirm its role in the increase of blood cholesterol, which ultimately may contribute to increased cardiovascular risk in this population.
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Affiliation(s)
- Maria R Emma
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy
| | - Lydia Giannitrapani
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy; Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Daniela Cabibi
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Rossana Porcasi
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Gianni Pantuso
- Department of Surgical, Oncological and Oral Sciences, Division of General and Oncological Surgery, University of Palermo, Palermo, Italy
| | - Giuseppa Augello
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy
| | - Rosaria V Giglio
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Noemi Lo Re
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy
| | - Adele R Capitano
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Giuseppe Montalto
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy; Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Maurizio Soresi
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy.
| | - Melchiorre Cervello
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy.
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32
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Malvandi AM, Canclini L, Alliaj A, Magni P, Zambon A, Catapano AL. Progress and prospects of biological approaches targeting PCSK9 for cholesterol-lowering, from molecular mechanism to clinical efficacy. Expert Opin Biol Ther 2020; 20:1477-1489. [PMID: 32715821 DOI: 10.1080/14712598.2020.1801628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Cardiovascular disorders are one of the leading causes of mortality and morbidity worldwide. Recent advances showed a promising role of proprotein convertase subtilisin/kexin type 9 (PCSK9) as a critical player in regulating plasma LDL levels and lipid metabolism. AREAS COVERED This review addresses the molecular functions of PCSK9 with a vision on the clinical progress of utilizing monoclonal antibodies and other biological approaches to block PCSK9 activity. The successful clinical trials with monoclonal antibodies are reviewed. Recent advances in (pre)clinical trials of other biological approaches, such as small interfering RNAs, are also discussed. EXPERT OPINION Discovery of PCSK9 and clinical use of its inhibitors to manage lipid metabolism is a step forward in hypolipidaemic therapy. A better understanding of the molecular activity of PCSK9 can help to identify new approaches in the inhibition of PCSK9 expression/activity. Whether if PCSK9 plays a role in other cardiometabolic conditions may provide grounds for further development of therapies.
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Affiliation(s)
| | - Laura Canclini
- IRCCS Multimedica , Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano , Milan, Italy
| | | | - Paolo Magni
- IRCCS Multimedica , Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano , Milan, Italy
| | - Alberto Zambon
- IRCCS Multimedica , Milan, Italy.,Department of Medicine, Università degli Studi di Padova , Padua, Italy
| | - Alberico Luigi Catapano
- IRCCS Multimedica , Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano , Milan, Italy
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33
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Guo S, Xia XD, Gu HM, Zhang DW. Proprotein Convertase Subtilisin/Kexin-Type 9 and Lipid Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1276:137-156. [DOI: 10.1007/978-981-15-6082-8_9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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34
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Wang WA, Agellon LB, Michalak M. Organellar Calcium Handling in the Cellular Reticular Network. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a038265. [PMID: 31358518 DOI: 10.1101/cshperspect.a038265] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ca2+ is an important intracellular messenger affecting diverse cellular processes. In eukaryotic cells, Ca2+ is handled by a myriad of Ca2+-binding proteins found in organelles that are organized into the cellular reticular network (CRN). The network is comprised of the endoplasmic reticulum, Golgi apparatus, lysosomes, membranous components of the endocytic and exocytic pathways, peroxisomes, and the nuclear envelope. Membrane contact sites between the different components of the CRN enable the rapid movement of Ca2+, and communication of Ca2+ status, within the network. Ca2+-handling proteins that reside in the CRN facilitate Ca2+ sensing, buffering, and cellular signaling to coordinate the many processes that operate within the cell.
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Affiliation(s)
- Wen-An Wang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2S7, Canada
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2S7, Canada
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35
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Sánchez-Hernández RM, Di Taranto MD, Benito-Vicente A, Uribe KB, Lamiquiz-Moneo I, Larrea-Sebal A, Jebari S, Galicia-Garcia U, Nóvoa FJ, Boronat M, Wägner AM, Civeira F, Martín C, Fortunato G. The Arg499His gain-of-function mutation in the C-terminal domain of PCSK9. Atherosclerosis 2019; 289:162-172. [PMID: 31518966 DOI: 10.1016/j.atherosclerosis.2019.08.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 12/26/2022]
Abstract
BACKGROUND AND AIMS Familial hypercholesterolemia (FH) is a monogenic disease characterized by high levels of low-density lipoprotein cholesterol and premature atherosclerotic cardiovascular disease. FH is caused by loss of function mutations in genes encoding LDL receptor (LDLR), and Apolipoprotein B (APOB) or gain of function (GOF) mutations in proprotein convertase subtilisin/kexin type 9 (PCSK9). In this study, we identified a novel variant in PCSK9, p.(Arg499His), located in the C-terminal domain, in two unrelated FH patients from Spain and Italy. METHODS We studied familial segregation and determined variant activity in vitro. RESULTS We determined PCSK9 expression, secretion and activity of the variant in transfected HEK293 cells; extracellular activity of the recombinant p.(Arg499His) PCSK9 variant in HEK 293 and HepG2 cells; PCSK9 affinity to the LDL receptor at neutral and acidic pH; the mechanism of action of the p.(Arg499His) PCSK9 variant by co-transfection with a soluble construct of the LDL receptor and by determining total PCSK9 intracellular accumulation when endosomal acidification is impaired and when an excess of soluble LDLr is present in the culture medium. Our results show high LDL-C concentrations and FH phenotype in p.(Arg499His) carriers. In vitro functional characterization shows that p.(Arg499His) PCSK9 variant causes a reduction in LDLr expression and LDL uptake. An intracellular activity for this variant is also shown when blocking the activity of secreted PCSK9 and by inhibiting endosomal acidification. CONCLUSIONS We demonstrated that p.(Arg499His) PCSK9 variant causes a direct intracellular degradation of LDLr therefore causing FH by reducing LDLr availability.
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Affiliation(s)
- Rosa M Sánchez-Hernández
- Sección de Endocrinología y Nutrición, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS) de la Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Maria Donata Di Taranto
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Napoli and CEINGE S.C.a r.l, Biotecnologie Avanzate, Napoli, Italy
| | - Asier Benito-Vicente
- Instituto Biofisika (UPV/EHU, CSIC) and Departamento de Bioquímica, Universidad del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Kepa B Uribe
- Instituto Biofisika (UPV/EHU, CSIC) and Departamento de Bioquímica, Universidad del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Itziar Lamiquiz-Moneo
- Hospital Universitario Miguel Servet. IIS Aragon. CIBERCV. Universidad de Zaragoza, Zaragoza, Spain
| | - Asier Larrea-Sebal
- Instituto Biofisika (UPV/EHU, CSIC) and Departamento de Bioquímica, Universidad del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Shifa Jebari
- Instituto Biofisika (UPV/EHU, CSIC) and Departamento de Bioquímica, Universidad del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Unai Galicia-Garcia
- Instituto Biofisika (UPV/EHU, CSIC), Barrio Sarriena s/n, 48940, Leioa, Bizkaia, Spain
| | - F Javier Nóvoa
- Sección de Endocrinología y Nutrición, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS) de la Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Mauro Boronat
- Sección de Endocrinología y Nutrición, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS) de la Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Ana M Wägner
- Sección de Endocrinología y Nutrición, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS) de la Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Fernando Civeira
- Hospital Universitario Miguel Servet. IIS Aragon. CIBERCV. Universidad de Zaragoza, Zaragoza, Spain
| | - César Martín
- Instituto Biofisika (UPV/EHU, CSIC) and Departamento de Bioquímica, Universidad del País Vasco, Apdo. 644, 48080, Bilbao, Spain.
| | - Giuliana Fortunato
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Napoli and CEINGE S.C.a r.l, Biotecnologie Avanzate, Napoli, Italy.
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Abstract
PURPOSE OF REVIEW The purpose of this review is to highlight the recent findings of one of the most promising therapeutic targets in LDL cholesterol (LDL-C) management, proprotein convertase subtilisin/kexin type 9 (PCSK9). RECENT FINDINGS Endoplasmic reticulum cargo receptor, surfeit locus protein 4 interacts with PCSK9 and regulates its exit from endoplasmic reticulum and its secretion. Once secreted, PCSK9 binds to heparin sulfate proteoglycans on the hepatocyte surface and this binding is required for PCSK9-LDL receptor (LDLR) complex formation and LDLR degradation. Posttranscriptionally, recent work has shown that PCSK9 gets degraded in lysosomes by activation of the glucagon receptor signaling, providing more data on the hormonal regulation of PCSK9. Finally, human studies with PCSK9 inhibitors offered more evidence on their benefits and safe use. SUMMARY Recent work on the regulation of PCSK9 has enhanced our understanding of its biology, which may provide important information for future PCSK9-based therapies.
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Affiliation(s)
- Stefano Spolitu
- Department of Medicine, Columbia University, New York, New York, USA
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37
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Safaeian L, Vaseghi G, Jabari H, Dana N. Evolocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, promotes angiogenesis in vitro. Can J Physiol Pharmacol 2019; 97:352-358. [DOI: 10.1139/cjpp-2018-0542] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The proprotein convertases family is involved in several physiological processes such as cell growth, migration, and angiogenesis, and also in different pathological conditions. Evolocumab, an inhibitor of proprotein convertase subtilisin/kexin type 9 (PCSK9), has recently been approved for treatment of hypercholesterolemia. This study aimed to investigate the effect of evolocumab on angiogenesis in human umbilical vein endothelial cells (HUVECs). Cell proliferation and migration were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell methods. In vitro angiogenesis was assessed by tube formation assay. Vascular endothelial growth factor (VEGF) secretion by HUVECs was also determined using an enzyme-linked immunosorbent assay kit. Evolocumab significantly increased HUVECs viability at 100 μg/mL. Significant enhancement in cell migration, and mean tubules length and size was observed at the concentrations of 10 and 100 μg/mL and also in mean number of junctions at the concentration of 100 μg/mL. Administration of evolocumab at the concentration of 10 μg/mL increased VEGF release into supernatants of HUVECs. Findings of this investigation provided in vitro evidence for pro-angiogenic activity of evolocumab through promoting cell proliferation, migration, tubulogenesis, and VEGF secretion in HUVECs.
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Affiliation(s)
- Leila Safaeian
- Department of Pharmacology and Toxicology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
- Research and Development Office, Vice Chancellery for Food and Drugs, Isfahan University of Medical Sciences, Isfahan, Iran
- Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Golnaz Vaseghi
- Isfahan Cardiovascular Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hedieh Jabari
- Department of Pharmacology and Toxicology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nasim Dana
- Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
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38
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PCSK9: from biology to clinical applications. Pathology 2019; 51:177-183. [DOI: 10.1016/j.pathol.2018.10.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 10/03/2018] [Accepted: 10/03/2018] [Indexed: 01/07/2023]
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39
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Deng SJ, Alabi A, Gu HM, Adijiang A, Qin S, Zhang DW. Identification of amino acid residues in the ligand binding repeats of LDL receptor important for PCSK9 binding. J Lipid Res 2019; 60:516-527. [PMID: 30617148 PMCID: PMC6399494 DOI: 10.1194/jlr.m089193] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/18/2018] [Indexed: 12/13/2022] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDL receptor (LDLR) degradation, increasing plasma levels of LDL cholesterol and the risk of cardiovascular disease. We have previously shown that, in addition to the epidermal growth factor precursor homology repeat-A of LDLR, at least three ligand-binding repeats (LRs) of LDLR are required for PCSK9-promoted LDLR degradation. However, how exactly the LRs contribute to PCSK9’s action on the receptor is not completely understood. Here, we found that substitution of Asp at position 172 in the linker between the LR4 and LR5 of full-length LDLR with Asn (D172N) reduced PCSK9 binding at pH 7.4 (mimic cell surface), but not at pH 6.0 (mimic endosomal environment). On the other hand, mutation of Asp at position 203 in the LR5 of full-length LDLR to Asn (D203N) significantly reduced PCSK9 binding at both pH 7.4 and pH 6.0. D203N also significantly reduced the ability of LDLR to mediate cellular LDL uptake, whereas D172N had no detectable effect. These findings indicate that amino acid residues in the LRs of LDLR play an important role in PCSK9 binding to the receptor.
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Affiliation(s)
- Shi-Jun Deng
- Department of Pediatrics, Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
| | - Adekunle Alabi
- Department of Pediatrics, Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada.,Department of Biochemistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Hong-Mei Gu
- Department of Pediatrics, Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
| | - Ayinuer Adijiang
- Department of Pediatrics, Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
| | - Shucun Qin
- Institute of Atherosclerosis, Taishan Medical University, Taian, China
| | - Da-Wei Zhang
- Department of Pediatrics, Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada .,Department of Biochemistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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40
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Abstract
PURPOSE OF REVIEW Our primary objective is to review the most recent findings on the biology of PCSK9 and on two key aspects of PCSK9 inhibition beyond LDL control of great clinical relevance: the regulation of lipoprotein (a) circulating levels by PCSK9 inhibitors and the putative diabetogenic effects of these novel therapies. RECENT FINDINGS The reality of two distinct extracellular and intracellular pathways by which PCSK9 decreases the abundance of the LDLR at the surface of many cell types, most importantly hepatocytes, has recently been established. In contrast, the exact mechanisms by which PCSK9 inhibitors lower the circulating levels of lipoprotein (a) remain a point of major dispute. Despite strong indications from genetic studies that PCSK9 inhibition should increase diabetes risk, no such effect has been observed in clinical trials, and in-vitro and in-vivo studies do not clarify this issue. SUMMARY The trafficking pathways by which PCSK9 enhance LDLR degradation via the endolysosomal extracellular route or via the Golgi-lysosomal intracellular route remain to be fully elucidated. The mechanisms by which PCSK9 inhibitors reduce lipoprotein (a) also merit additional research efforts. The role of PCSK9 on glucose metabolism should likewise be studied in depth.
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Abstract
Clinical trials have unequivocally shown that inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) efficaciously and safely prevents cardiovascular events by lowering levels of LDL cholesterol. PCSK9 in the circulation is derived mainly from the liver, but the protein is also expressed in the pancreas, the kidney, the intestine and the central nervous system. Although PCSK9 modulates cholesterol metabolism by regulating LDL receptor expression in the liver, in vitro and in vivo studies have suggested that PCSK9 is involved in various other physiological processes. Although therapeutic PCSK9 inhibition could theoretically have undesired effects by interfering with these non-cholesterol-related processes, studies of individuals with genetically determined reduced PCSK9 function and clinical trials of PCSK9 inhibitors have not revealed clinically meaningful adverse consequences of almost completely eradicating PCSK9 from the circulation. The clinical implications of PCSK9 functions beyond lipid metabolism in terms of wanted or unwanted effects of therapeutic PCSK9 inhibition therefore appear to be limited. The objective of this Review is to describe the physiological role of PCSK9 beyond the LDL receptor to provide a rational basis for monitoring the effects of PCSK9 inhibition as these drugs gain traction in the clinic.
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Affiliation(s)
| | - Gilles Lambert
- Inserm UMR 1188 DéTROI, Université de La Réunion, Saint-Denis de La Réunion, France
| | - Bertrand Cariou
- L'institut du thorax, INSERM, CNRS, Université de Nantes, CHU Nantes, Nantes, France
| | - G Kees Hovingh
- Department of Vascular Medicine, Academisch Medisch Centrum, Amsterdam, Netherlands.
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Small molecules as inhibitors of PCSK9: Current status and future challenges. Eur J Med Chem 2018; 162:212-233. [PMID: 30448414 DOI: 10.1016/j.ejmech.2018.11.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/13/2018] [Accepted: 11/05/2018] [Indexed: 12/11/2022]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays an important role in regulating lipoprotein metabolism by binding to low-density lipoprotein receptors (LDLRs), leading to their degradation. LDL cholesterol (LDL-C) lowering drugs that operate through the inhibition of PCSK9 are being pursued for the management of hypercholesterolemia and reducing its associated atherosclerotic cardiovascular disease (CVD) risk. Two PCSK9-blocking monoclonal antibodies (mAbs), alirocumab and evolocumab, were approved in 2015. However, the high costs of PCSK9 antibody drugs impede their prior authorization practices and reduce their long-term adherence. Given the potential of small-molecule drugs, the development of small-molecule PCSK9 inhibitors has attracted considerable attention. This article provides an overview of the recent development of small-molecule PCSK9 inhibitors disclosed in the literature and patent applications, and different approaches that have been pursued to modulate the functional activity of PCSK9 using small molecules are described. Challenges and potential strategies in developing small-molecule PCSK9 inhibitors are also discussed.
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43
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Abstract
Unknown 15 years ago, PCSK9 (proprotein convertase subtilisin/kexin type 9) is now common parlance among scientists and clinicians interested in prevention and treatment of atherosclerotic cardiovascular disease. What makes this story so special is not its recent discovery nor the fact that it uncovered previously unknown biology but rather that these important scientific insights have been translated into an effective medical therapy in record time. Indeed, the translation of this discovery to novel therapeutic serves as one of the best examples of how genetic insights can be leveraged into intelligent target drug discovery. The PCSK9 saga is unfolding quickly but is far from complete. Here, we review major scientific understandings as they relate to the role of PCSK9 in lipoprotein metabolism and atherosclerotic cardiovascular disease and the impact that therapies designed to inhibit its action are having in the clinical setting.
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Affiliation(s)
- Michael D Shapiro
- From the Center for Preventive Cardiology, Knight Cardiovascular Institute, Oregon Health & Science University, Portland
| | - Hagai Tavori
- From the Center for Preventive Cardiology, Knight Cardiovascular Institute, Oregon Health & Science University, Portland
| | - Sergio Fazio
- From the Center for Preventive Cardiology, Knight Cardiovascular Institute, Oregon Health & Science University, Portland.
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44
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Seidah NG, Chrétien M, Mbikay M. The ever-expanding saga of the proprotein convertases and their roles in body homeostasis: emphasis on novel proprotein convertase subtilisin kexin number 9 functions and regulation. Curr Opin Lipidol 2018; 29:144-150. [PMID: 29342010 DOI: 10.1097/mol.0000000000000484] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW The nine members of the proprotein convertase family play major physiological roles during development and in the adult, and their dysregulation leads to various diseases. The primary objective of this article is to review recent findings on the clinical importance of some of these convertases concentrating mostly on PCSK9, the ninth member of the convertase family. This includes the transcriptional and translational regulation of PCSK9, its ability to enhance the degradation of LDL receptor (LDLR), and the implication of PCSK9 in inflammation and sepsis. RECENT FINDINGS PCSK9 levels are upregulated by E2F1 and reduced by specific miRNAs and by Annexin A2 that bind the 3' end of its mRNA. The implication of the LDLR in the clearance of pathogenic bacterial debris in mice and human puts in perspective a new role for PCSK9 in the regulation of sepsis. The specific implication of the LDLR in the clearance of Lp(a) is now confirmed by multiple studies of PCSK9 inhibition in human cohorts. SUMMARY Emerging data suggest that PCSK9 can be regulated at the transcriptional and translational levels by specific factors and miRNAs. The identification of a novel pocket in the catalytic domain of PCSK9 represents a harbinger for a new class of small inhibitor drugs. The implication of the LDLR in reducing the effects of bacterially induced sepsis has been supported by both human and mouse data. Outcome studies confirmed the clinical importance of reducing PCSK9 levels. The present review puts in perspective new developments in the PCSK9 biology and its regulation of the LDLR. VIDEO ABSTRACT: http://links.lww.com/COL/A17.
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Affiliation(s)
| | - Michel Chrétien
- Laboratory of Functional Endoproteolysis, Montreal Clinical Research Institute of Montreal (IRCM), Montreal, Quebec, Canada
| | - Majambu Mbikay
- Laboratory of Functional Endoproteolysis, Montreal Clinical Research Institute of Montreal (IRCM), Montreal, Quebec, Canada
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45
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Lebeau P, Platko K, Al-Hashimi AA, Byun JH, Lhoták Š, Holzapfel N, Gyulay G, Igdoura SA, Cool DR, Trigatti B, Seidah NG, Austin RC. Loss-of-function PCSK9 mutants evade the unfolded protein response sensor GRP78 and fail to induce endoplasmic reticulum stress when retained. J Biol Chem 2018; 293:7329-7343. [PMID: 29593095 DOI: 10.1074/jbc.ra117.001049] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/15/2018] [Indexed: 01/07/2023] Open
Abstract
The proprotein convertase subtilisin/kexin type-9 (PCSK9) plays a central role in cardiovascular disease (CVD) by degrading hepatic low-density lipoprotein receptor (LDLR). As such, loss-of-function (LOF) PCSK9 variants that fail to exit the endoplasmic reticulum (ER) increase hepatic LDLR levels and lower the risk of developing CVD. The retention of misfolded protein in the ER can cause ER stress and activate the unfolded protein response (UPR). In this study, we investigated whether a variety of LOF PCSK9 variants that are retained in the ER can cause ER stress and hepatic cytotoxicity. Although overexpression of these PCSK9 variants caused an accumulation in the ER of hepatocytes, UPR activation or apoptosis was not observed. Furthermore, ER retention of endogenous PCSK9 via splice switching also failed to induce the UPR. Consistent with these in vitro studies, overexpression of PCSK9 in the livers of mice had no impact on UPR activation. To elucidate the cellular mechanism to explain these surprising findings, we observed that the 94-kDa glucose-regulated protein (GRP94) sequesters PCSK9 away from the 78-kDa glucose-regulated protein (GRP78), the major activator of the UPR. As a result, GRP94 knockdown increased the stability of GRP78-PCSK9 complex and resulted in UPR activation following overexpression of ER-retained PCSK9 variants relative to WT secreted controls. Given that overexpression of these LOF PCSK9 variants does not cause UPR activation under normal homeostatic conditions, therapeutic strategies aimed at blocking the autocatalytic cleavage of PCSK9 in the ER represent a viable strategy for reducing circulating PCSK9.
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Affiliation(s)
- Paul Lebeau
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Khrystyna Platko
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Ali A Al-Hashimi
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Jae Hyun Byun
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Šárka Lhoták
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Nicholas Holzapfel
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Gabriel Gyulay
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
| | - Suleiman A Igdoura
- Departments of Biology and Pathology, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - David R Cool
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, Ohio, 45435-0001
| | - Bernardo Trigatti
- Thrombosis and Atherosclerosis Research Institute (TaARI), Hamilton Health Sciences and McMaster University, Hamilton, Ontario L8L 2X2, Canada; Departments of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Richard C Austin
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Center for Kidney Research, Hamilton, Ontario L8N 4A6, Canada; Thrombosis and Atherosclerosis Research Institute (TaARI), Hamilton Health Sciences and McMaster University, Hamilton, Ontario L8L 2X2, Canada.
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46
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Karagiannis AD, Liu M, Toth PP, Zhao S, Agrawal DK, Libby P, Chatzizisis YS. Pleiotropic Anti-atherosclerotic Effects of PCSK9 Inhibitors From Molecular Biology to Clinical Translation. Curr Atheroscler Rep 2018. [DOI: 10.1007/s11883-018-0718-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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47
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Mnasri N, Mamarbachi M, Allen BG, Mayer G. 5-Azacytidine engages an IRE1α-EGFR-ERK1/2 signaling pathway that stabilizes the LDL receptor mRNA. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1861:29-40. [PMID: 29208426 DOI: 10.1016/j.bbagrm.2017.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/09/2017] [Accepted: 11/29/2017] [Indexed: 01/06/2023]
Abstract
Hepatic low-density lipoprotein receptor (LDLR) is the primary conduit for the clearance of plasma LDL-cholesterol and increasing its expression represents a central goal for treating cardiovascular disease. However, LDLR mRNA is unstable and undergoes rapid turnover mainly due to the three AU-rich elements (ARE) in its proximal 3'-untranslated region (3'-UTR). Herein, our data revealed that 5-azacytidine (5-AzaC), an antimetabolite used in the treatment of myelodysplastic syndrome, stabilizes the LDLR mRNA through a previously unrecognized signaling pathway resulting in a strong increase of its protein level in human hepatocytes in culture. 5-AzaC caused a sustained activation of the inositol-requiring enzyme 1α (IRE1α) kinase domain and c-Jun N-terminal kinase (JNK) independently of endoplasmic reticulum stress. This resulted in activation of the epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase1/2 (ERK1/2) that, in turn, stabilized LDLR mRNA. Systematic mutation of the AREs (ARE1-3) in the LDLR 3'UTR and expression of each mutant coupled to a luciferase reporter in Huh7 cells demonstrated that ARE1 is required for rapid LDLR mRNA decay and 5-AzaC-induced mRNA stabilization via the IRE1α-EGFR-ERK1/2 signaling cascade. The characterization of this pathway will help to reveal potential targets to enhance plasma LDL clearance and novel cholesterol-lowering therapeutic strategies.
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Affiliation(s)
- Nourhen Mnasri
- Laboratory of Molecular and Cellular Biology, Montreal Heart Institute, Montréal, QC, Canada; Department of Biomedical Sciences, Université de Montréal, Montréal, QC, Canada
| | - Maya Mamarbachi
- Molecular Biology Core Facility, Montreal Heart Institute, Montréal, QC, Canada
| | - Bruce G Allen
- Laboratory of Cell Biology, Montreal Heart Institute, Montréal, QC, Canada; Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Gaétan Mayer
- Laboratory of Molecular and Cellular Biology, Montreal Heart Institute, Montréal, QC, Canada; Faculty of Pharmacy, Université de Montréal, Montréal, QC, Canada.
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48
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Lee S, Kim S, Hwang S, Cherrington NJ, Ryu DY. Dysregulated expression of proteins associated with ER stress, autophagy and apoptosis in tissues from nonalcoholic fatty liver disease. Oncotarget 2017; 8:63370-63381. [PMID: 28968997 PMCID: PMC5609929 DOI: 10.18632/oncotarget.18812] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 06/04/2017] [Indexed: 01/23/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is categorized into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) and has emerged as a risk factor for more critical clinical conditions. However, the underlying mechanisms of NAFLD pathogenesis are not fully understood. In this study, expression of proteins associated with endoplasmic reticulum (ER) stress, apoptosis and autophagy were analyzed in normal, NAFL and NASH human livers by western blotting. Levels of some ER stress-transducing transcription factors, including cleaved activating transcription factor 6, were higher in NASH than in the normal tissues. However, the expression of a majority of the ER chaperones and foldases analyzed, including glucose-regulated protein 78 and ER protein 44, was lower in NASH than in the normal tissues. Levels of apoptosis markers, such as cleaved poly (ADP-ribose) polymerase, were also lower in NASH tissues, in which expression of some B-cell lymphoma-2 family proteins was up- or down-regulated compared to the normal tissues. The level of the autophagy substrate p62 was not different in NASH and normal tissues, although some autophagy regulators were up- or down-regulated in the NASH tissues compared to the normal tissues. Levels of most of the proteins analyzed in NAFL tissues were either similar to those in one of the other two types, NASH and normal, or were somewhere in between. Together, these findings suggest that regulation of certain important tissues processes involved in protein quality control and cell survival were broadly compromised in the NAFLD tissues.
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Affiliation(s)
- Seungwoo Lee
- BK21 Plus Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Soohee Kim
- BK21 Plus Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Seungwoo Hwang
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Republic of Korea
| | | | - Doug-Young Ryu
- BK21 Plus Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Gwanak-gu, Seoul 08826, Republic of Korea
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49
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Abstract
PURPOSE OF REVIEW To highlight very recent studies identifying novel regulatory molecules and mechanisms in plasma lipid metabolism. RECENT FINDINGS Two novel regulatory mechanisms of LDL receptor (LDLR) intracellular trafficking have been described. The "COMMD/CCDC22/CCDC93" and "Wiskott-Aldrich syndrome protein and SCAR homologue" complexes were found to be involved in LDLR endosomal sorting and recycling, whereas the GRP94 was shown to protect LDLR from early degradation within the hepatocyte secretory pathway. Additionally, the transcription factors PHD1 and Bmal1 were identified to regulate LDL-C levels in mice by modulating cholesterol excretion. Important advances are reported on the relevance of two Genome Wide Association Studies hits: Reassessment of GALNT2 showed, in contrast to previous reports, that loss of GALNT2 reduces HDL-cholesterol in humans and other mammalian species, while phospholipid transfer protein was identified as an additional target of GALNT2. Tetratricopeptide repeat domain protein 39B was found to promote ubiquitination and degradation of Liver X receptor, and its deficiency increased HDL-cholesterol and cholesterol removal while also inhibiting lipogenesis in mice. SUMMARY The unraveling of mechanisms how new factors modulate plasma lipid levels keep providing interesting opportunities to rationally design novel therapies to treat cardiovascular disease but also metabolic disorders.
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Affiliation(s)
- Natalia Loaiza
- University of Groningen, University Medical Center Groningen, Department of Pediatrics, Section of Molecular Genetics, Groningen, The Netherlands
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50
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Segura E, Bourdin B, Tétreault MP, Briot J, Allen BG, Mayer G, Parent L. Proteolytic cleavage of the hydrophobic domain in the Ca Vα2δ1 subunit improves assembly and activity of cardiac Ca V1.2 channels. J Biol Chem 2017; 292:11109-11124. [PMID: 28495885 DOI: 10.1074/jbc.m117.784355] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/24/2017] [Indexed: 11/06/2022] Open
Abstract
Voltage-gated L-type CaV1.2 channels in cardiomyocytes exist as heteromeric complexes with the pore-forming CaVα1, CaVβ, and CaVα2δ1 subunits. The full complement of subunits is required to reconstitute the native-like properties of L-type Ca2+ currents, but the molecular determinants responsible for the formation of the heteromeric complex are still being studied. Enzymatic treatment with phosphatidylinositol-specific phospholipase C, a phospholipase C specific for the cleavage of glycosylphosphatidylinositol (GPI)-anchored proteins, disrupted plasma membrane localization of the cardiac CaVα2δ1 prompting us to investigate deletions of its hydrophobic transmembrane domain. Patch-clamp experiments indicated that the C-terminally cleaved CaVα2δ1 proteins up-regulate CaV1.2 channels. In contrast, deleting the residues before the single hydrophobic segment (CaVα2δ1 Δ1059-1063) impaired current up-regulation. CaVα2δ1 mutants G1060I and G1061I nearly eliminated the cell-surface fluorescence of CaVα2δ1, indicated by two-color flow cytometry assays and confocal imaging, and prevented CaVα2δ1-mediated increase in peak current density and modulation of the voltage-dependent gating of CaV1.2. These impacts were specific to substitutions with isoleucine residues because functional modulation was partially preserved in CaVα2δ1 G1060A and G1061A proteins. Moreover, C-terminal fragments exhibited significantly altered mobility in denatured immunoblots of CaVα2δ1 G1060I and CaVα2δ1 G1061I, suggesting that these mutant proteins were impaired in proteolytic processing. Finally, CaVα2δ1 Δ1059-1063, but not CaVα2δ1 G1060A, failed to co-immunoprecipitate with CaV1.2. Altogether, our data support a model in which small neutral hydrophobic residues facilitate the post-translational cleavage of the CaVα2δ1 subunit at the predicted membrane interface and further suggest that preventing GPI anchoring of CaVα2δ1 averts its cell-surface expression, its interaction with CaVα1, and modulation of CaV1.2 currents.
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Affiliation(s)
- Emilie Segura
- From the Départements de Pharmacologie et Physiologie and.,the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Benoîte Bourdin
- the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Marie-Philippe Tétreault
- the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Julie Briot
- From the Départements de Pharmacologie et Physiologie and.,the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Bruce G Allen
- the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada.,Médecine, Faculté de Médecine
| | - Gaétan Mayer
- the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada.,the Faculté de Pharmacie, and
| | - Lucie Parent
- From the Départements de Pharmacologie et Physiologie and .,the Centre de Recherche de l'Institut de Cardiologie de Montréal, Université de Montréal, Montréal, Québec H3C 3J7, Canada
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