1
|
Wang S, Wang X, Li S, Sun X, Xue M, Di D, Zhang A, Zhang Y, Xia Y, Zhou T, Fan Z. Maize lipid droplet-associated protein 2 is recruited by a virus to enhance viral multiplication and infection through regulating cellular fatty acid metabolism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 39007841 DOI: 10.1111/tpj.16934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/05/2024] [Accepted: 06/26/2024] [Indexed: 07/16/2024]
Abstract
Pathogen infection induces massive reprogramming of host primary metabolism. Lipid and fatty acid (FA) metabolism is generally disrupted by pathogens and co-opted for their proliferation. Lipid droplets (LDs) that play important roles in regulating cellular lipid metabolism are utilized by a variety of pathogens in mammalian cells. However, the function of LDs during pathogenic infection in plants remains unknown. We show here that infection by rice black streaked dwarf virus (RBSDV) affects the lipid metabolism of maize, which causes elevated accumulation of C18 polyunsaturated fatty acids (PUFAs) leading to viral proliferation and symptom development. The overexpression of one of the two novel LD-associated proteins (LDAPs) of maize (ZmLDAP1 and ZmLDAP2) induces LD clustering. The core capsid protein P8 of RBSDV interacts with ZmLDAP2 and prevents its degradation through the ubiquitin-proteasome system mediated by a UBX domain-containing protein, PUX10. In addition, silencing of ZmLDAP2 downregulates the expression of FA desaturase genes in maize, leading to a decrease in C18 PUFAs levels and suppression of RBSDV accumulation. Our findings reveal that plant virus may recruit LDAP to regulate cellular FA metabolism to promote viral multiplication and infection. These results expand the knowledge of LD functions and viral infection mechanisms in plants.
Collapse
Affiliation(s)
- Siyuan Wang
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Xinyu Wang
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Siqi Li
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Xi Sun
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Mingshuo Xue
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Dianping Di
- Plant Protection Institute, Hebei Academy of Agriculture and Forestry Sciences, Baoding, 071000, China
| | - Aihong Zhang
- Plant Protection Institute, Hebei Academy of Agriculture and Forestry Sciences, Baoding, 071000, China
| | - Yongjiang Zhang
- Chinese Academy of Inspection and Quarantine, Beijing, 100176, China
| | - Yiji Xia
- Department of Biology, Hong Kong Baptist University, Hong Kong, SAR, China
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Tao Zhou
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
| | - Zaifeng Fan
- MARA-Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, and State Key Laboratory for Maize Bio-breeding, China Agricultural University, Beijing, 100193, China
- Sanya Institute of China Agricultural University, Sanya, 572025, China
| |
Collapse
|
2
|
Hsia JZ, Liu D, Haynes L, Cruz-Cosme R, Tang Q. Lipid Droplets: Formation, Degradation, and Their Role in Cellular Responses to Flavivirus Infections. Microorganisms 2024; 12:647. [PMID: 38674592 PMCID: PMC11051834 DOI: 10.3390/microorganisms12040647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/18/2024] [Accepted: 03/22/2024] [Indexed: 04/28/2024] Open
Abstract
Lipid droplets (LDs) are cellular organelles derived from the endoplasmic reticulum (ER), serving as lipid storage sites crucial for maintaining cellular lipid homeostasis. Recent attention has been drawn to their roles in viral replication and their interactions with viruses. However, the precise biological functions of LDs in viral replication and pathogenesis remain incompletely understood. To elucidate the interaction between LDs and viruses, it is imperative to comprehend the biogenesis of LDs and their dynamic interactions with other organelles. In this review, we explore the intricate pathways involved in LD biogenies within the cytoplasm, encompassing the uptake of fatty acid from nutrients facilitated by CD36-mediated membranous protein (FABP/FATP)-FA complexes, and FA synthesis via glycolysis in the cytoplasm and the TCL cycle in mitochondria. While LD biogenesis primarily occurs in the ER, matured LDs are intricately linked to multiple organelles. Viral infections can lead to diverse consequences in terms of LD status within cells post-infection, potentially involving the breakdown of LDs through the activation of lipophagy. However, the exact mechanisms underlying LD destruction or accumulation by viruses remain elusive. The significance of LDs in viral replication renders them effective targets for developing broad-spectrum antivirals. Moreover, considering that reducing neutral lipids in LDs is a strategy for anti-obesity treatment, LD depletion may not pose harm to cells. This presents LDs as promising antiviral targets for developing therapeutics that are minimally or non-toxic to the host.
Collapse
Affiliation(s)
| | | | | | | | - Qiyi Tang
- Department of Microbiology, Howard University College of Medicine, Washington, DC 20059, USA; (J.Z.H.); (D.L.); (L.H.); (R.C.-C.)
| |
Collapse
|
3
|
Matthaei A, Joecks S, Frauenstein A, Bruening J, Bankwitz D, Friesland M, Gerold G, Vieyres G, Kaderali L, Meissner F, Pietschmann T. Landscape of protein-protein interactions during hepatitis C virus assembly and release. Microbiol Spectr 2024; 12:e0256222. [PMID: 38230952 PMCID: PMC10846047 DOI: 10.1128/spectrum.02562-22] [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: 07/05/2022] [Accepted: 10/11/2023] [Indexed: 01/18/2024] Open
Abstract
Assembly of infectious hepatitis C virus (HCV) particles requires multiple cellular proteins including for instance apolipoprotein E (ApoE). To describe these protein-protein interactions, we performed an affinity purification mass spectrometry screen of HCV-infected cells. We used functional viral constructs with epitope-tagged envelope protein 2 (E2), protein (p) 7, or nonstructural protein 4B (NS4B) as well as cells expressing a tagged variant of ApoE. We also evaluated assembly stage-dependent remodeling of protein complexes by using viral mutants carrying point mutations abrogating particle production at distinct steps of the HCV particle production cascade. Five ApoE binding proteins, 12 p7 binders, 7 primary E2 interactors, and 24 proteins interacting with NS4B were detected. Cell-derived PREB, STT3B, and SPCS2 as well as viral NS2 interacted with both p7 and E2. Only GTF3C3 interacted with E2 and NS4B, highlighting that HCV assembly and replication complexes exhibit largely distinct interactomes. An HCV core protein mutation, preventing core protein decoration of lipid droplets, profoundly altered the E2 interactome. In cells replicating this mutant, E2 interactions with HSPA5, STT3A/B, RAD23A/B, and ZNF860 were significantly enhanced, suggesting that E2 protein interactions partly depend on core protein functions. Bioinformatic and functional studies including STRING network analyses, RNA interference, and ectopic expression support a role of Rad23A and Rad23B in facilitating HCV infectious virus production. Both Rad23A and Rad23B are involved in the endoplasmic reticulum (ER)-associated protein degradation (ERAD). Collectively, our results provide a map of host proteins interacting with HCV assembly proteins, and they give evidence for the involvement of ER protein folding machineries and the ERAD pathway in the late stages of the HCV replication cycle.IMPORTANCEHepatitis C virus (HCV) establishes chronic infections in the majority of exposed individuals. This capacity likely depends on viral immune evasion strategies. One feature likely contributing to persistence is the formation of so-called lipo-viro particles. These peculiar virions consist of viral structural proteins and cellular lipids and lipoproteins, the latter of which aid in viral attachment and cell entry and likely antibody escape. To learn about how lipo-viro particles are coined, here, we provide a comprehensive overview of protein-protein interactions in virus-producing cells. We identify numerous novel and specific HCV E2, p7, and cellular apolipoprotein E-interacting proteins. Pathway analyses of these interactors show that proteins participating in processes such as endoplasmic reticulum (ER) protein folding, ER-associated protein degradation, and glycosylation are heavily engaged in virus production. Moreover, we find that the proteome of HCV replication sites is distinct from the assembly proteome, suggesting that transport process likely shuttles viral RNA to assembly sites.
Collapse
Affiliation(s)
- Alina Matthaei
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| | - Sebastian Joecks
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| | - Annika Frauenstein
- RG Experimental Systems Immunology, Max-Planck Institute for Biochemistry, Planegg, Bavaria, Germany
| | - Janina Bruening
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| | - Dorothea Bankwitz
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| | - Martina Friesland
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| | - Gisa Gerold
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
- Department of Biochemistry & Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Hannover, Lower Saxony, Germany
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
- Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, Umeå, Sweden
| | - Gabrielle Vieyres
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
- Junior Research Group “Cell Biology of RNA Viruses,” Leibniz Institute of Experimental Virology, Hamburg, Germany
| | - Lars Kaderali
- Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Germany
| | - Felix Meissner
- RG Experimental Systems Immunology, Max-Planck Institute for Biochemistry, Planegg, Bavaria, Germany
- Systems Immunology and Proteomics, Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Thomas Pietschmann
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Lower Saxony, Germany
| |
Collapse
|
4
|
Prado LG, Camara NOS, Barbosa AS. Cell lipid biology in infections: an overview. Front Cell Infect Microbiol 2023; 13:1148383. [PMID: 37868347 PMCID: PMC10587689 DOI: 10.3389/fcimb.2023.1148383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 09/22/2023] [Indexed: 10/24/2023] Open
Abstract
Lipids are a big family of molecules with a vast number of functions in the cell membranes, within the cytoplasm, and extracellularly. Lipid droplets (LDs) are the most common storage organelles and are present in almost every tissue type in the body. They also have structural functions serving as building blocks of cellular membranes and may be precursors of other molecules such as hormones, and lipoproteins, and as messengers in signal transduction. Fatty acids (FAs), such as sterol esters and triacylglycerols, are stored in LDs and are used in β-oxidation as fuel for tricarboxylic acid cycle (TCA) and adenosine triphosphate (ATP) generation. FA uptake and entrance in the cytoplasm are mediated by membrane receptors. After a cytoplasmic round of α- and β-oxidation, FAs are guided into the mitochondrial matrix by the L-carnitine shuttle system, where they are fully metabolized, and enter the TCA cycle. Pathogen infections may lead to impaired lipid metabolism, usage of membrane phospholipids, and LD accumulation in the cytoplasm of infected cells. Otherwise, bacterial pathogens may use lipid metabolism as a carbon source, thus altering the reactions and leading to cellular and organelles malfunctioning. This review aims to describe cellular lipid metabolism and alterations that occur upon infections.
Collapse
Affiliation(s)
- Luan Gavião Prado
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Niels Olsen Saraiva Camara
- Laboratório de Imunobiologia de Transplantes, Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
- Disciplina de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | | |
Collapse
|
5
|
Yue M, Hu B, Li J, Chen R, Yuan Z, Xiao H, Chang H, Jiu Y, Cai K, Ding B. Coronaviral ORF6 protein mediates inter-organelle contacts and modulates host cell lipid flux for virus production. EMBO J 2023; 42:e112542. [PMID: 37218505 PMCID: PMC10308351 DOI: 10.15252/embj.2022112542] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 04/16/2023] [Accepted: 05/08/2023] [Indexed: 05/24/2023] Open
Abstract
Lipid droplets (LDs) form inter-organelle contacts with the endoplasmic reticulum (ER) that promote their biogenesis, while LD contacts with mitochondria enhance β-oxidation of contained fatty acids. Viruses have been shown to take advantage of lipid droplets to promote viral production, but it remains unclear whether they also modulate the interactions between LDs and other organelles. Here, we showed that coronavirus ORF6 protein targets LDs and is localized to the mitochondria-LD and ER-LD contact sites, where it regulates LD biogenesis and lipolysis. At the molecular level, we find that ORF6 inserts into the LD lipid monolayer via its two amphipathic helices. ORF6 further interacts with ER membrane proteins BAP31 and USE1 to mediate ER-LDs contact formation. Additionally, ORF6 interacts with the SAM complex in the mitochondrial outer membrane to link mitochondria to LDs. In doing so, ORF6 promotes cellular lipolysis and LD biogenesis to reprogram host cell lipid flux and facilitate viral production.
Collapse
Affiliation(s)
- Mengzhen Yue
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Bing Hu
- Institute of Health Inspection and TestingHubei Provincial Center for Disease Control and PreventionWuhanChina
| | - Jiajia Li
- School of Pharmacy, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Ruifeng Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Zhen Yuan
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Hurong Xiao
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Haishuang Chang
- Shanghai Institute of Precision Medicine, Shanghai Ninth People's HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| | - Yaming Jiu
- Unit of Cell Biology and Imaging Study of Pathogen Host Interaction, The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of ShanghaiChinese Academy of SciencesShanghaiChina
| | - Kun Cai
- Institute of Health Inspection and TestingHubei Provincial Center for Disease Control and PreventionWuhanChina
| | - Binbin Ding
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Cell Architecture Research InstituteHuazhong University of Science and TechnologyWuhanChina
| |
Collapse
|
6
|
Qu Y, Wang W, Xiao MZX, Zheng Y, Liang Q. The interplay between lipid droplets and virus infection. J Med Virol 2023; 95:e28967. [PMID: 37496184 DOI: 10.1002/jmv.28967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/28/2023]
Abstract
As an intracellular parasite, the virus usurps cellular machinery and modulates cellular metabolism pathways to replicate itself in cells. Lipid droplets (LDs) are universally conserved energy storage organelles that not only play vital roles in maintaining lipid homeostasis but are also involved in viral replication. Increasing evidence has demonstrated that viruses take advantage of cellular lipid metabolism by targeting the biogenesis, hydrolysis, and lipophagy of LD during viral infection. In this review, we summarize the current knowledge about the modulation of cellular LD by different viruses, with a special emphasis on the Hepatitis C virus, Dengue virus, and SARS-CoV-2.
Collapse
Affiliation(s)
- Yafei Qu
- Center for Immune-Related Diseases at Shanghai Institute of Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Weili Wang
- Center for Immune-Related Diseases at Shanghai Institute of Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Maggie Z X Xiao
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Yuejuan Zheng
- The Research Center for Traditional Chinese Medicine, Shanghai Institute of Infectious Disease and Biosecurity, Shanghai University of Traditional Medicine, Shanghai, China
- Center for Traditional Chinese Medicine and Immunology Research, School of Basic Medical Sciences, Shanghai University of Traditional Medicine, Shanghai, China
| | - Qiming Liang
- Center for Immune-Related Diseases at Shanghai Institute of Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
7
|
Chen S, Harris M. NS5A domain I antagonises PKR to facilitate the assembly of infectious hepatitis C virus particles. PLoS Pathog 2023; 19:e1010812. [PMID: 36795772 PMCID: PMC9977016 DOI: 10.1371/journal.ppat.1010812] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 03/01/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
Hepatitis C virus NS5A is a multifunctional phosphoprotein comprised of three domains (DI, DII and DIII). DI and DII have been shown to function in genome replication, whereas DIII has a role in virus assembly. We previously demonstrated that DI in genotype 2a (JFH1) also plays a role in virus assembly, exemplified by the P145A mutant which blocked infectious virus production. Here we extend this analysis to identify two other conserved and surface exposed residues proximal to P145 (C142 and E191) that exhibited no defect in genome replication but impaired virus production. Further analysis revealed changes in the abundance of dsRNA, the size and distribution of lipid droplets (LD) and the co-localisation between NS5A and LDs in cells infected with these mutants, compared to wildtype. In parallel, to investigate the mechanism(s) underpinning this role of DI, we assessed the involvement of the interferon-induced double-stranded RNA-dependent protein kinase (PKR). In PKR-silenced cells, C142A and E191A exhibited levels of infectious virus production, LD size and co-localisation between NS5A and LD that were indistinguishable from wildtype. Co-immunoprecipitation and in vitro pulldown experiments confirmed that wildtype NS5A domain I (but not C142A or E191A) interacted with PKR. We further showed that the assembly phenotype of C142A and E191A was restored by ablation of interferon regulatory factor-1 (IRF1), a downstream effector of PKR. These data suggest a novel interaction between NS5A DI and PKR that functions to evade an antiviral pathway that blocks virus assembly through IRF1.
Collapse
Affiliation(s)
- Shucheng Chen
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
| |
Collapse
|
8
|
Islam KU, Anwar S, Patel AA, Mirdad MT, Mirdad MT, Azmi MI, Ahmad T, Fatima Z, Iqbal J. Global Lipidome Profiling Revealed Multifaceted Role of Lipid Species in Hepatitis C Virus Replication, Assembly, and Host Antiviral Response. Viruses 2023; 15:v15020464. [PMID: 36851679 PMCID: PMC9965260 DOI: 10.3390/v15020464] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/29/2023] [Accepted: 02/01/2023] [Indexed: 02/11/2023] Open
Abstract
Hepatitis C virus (HCV) is a major human pathogen that requires a better understanding of its interaction with host cells. There is a close association of HCV life cycle with host lipid metabolism. Lipid droplets (LDs) have been found to be crucial organelles that support HCV replication and virion assembly. In addition to their role in replication, LDs also have protein-mediated antiviral properties that are activated during HCV infection. Studies have shown that HCV replicates well in cholesterol and sphingolipid-rich membranes, but the ways in which HCV alters host cell lipid dynamics are not yet known. In this study, we performed a kinetic study to check the enrichment of LDs at different time points of HCV infection. Based on the LD enrichment results, we selected early and later time points of HCV infection for global lipidomic study. Early infection represents the window period for HCV sensing and host immune response while later infection represents the establishment of viral RNA replication, virion assembly, and egress. We identified the dynamic profile of lipid species at early and later time points of HCV infection by global lipidomic study using mass spectrometry. At early HCV infection, phosphatidylinositol phospholipids (PIPs), lysophosphatidic acid (LPA), triacyl glycerols (TAG), phosphatidylcholine (PC), and trihexosylceramides (Hex3Cer) were observed to be enriched. Similarly, free fatty acids (FFA), phosphatidylethanolamine (PE), N-acylphosphatidylethanolamines (NAPE), and tri acylglycerols were enriched at later time points of HCV infection. Lipids enriched at early time of infection may have role in HCV sensing, viral attachment, and immune response as LPA and PIPs are important for immune response and viral attachment, respectively. Moreover, lipid species observed at later infection may contribute to HCV replication and virion assembly as PE, FFA, and triacylglycerols are known for the similar function. In conclusion, we identified lipid species that exhibited dynamic profile across early and later time points of HCV infection compared to mock cells, which could be therapeutically relevant in the design of more specific and effective anti-viral therapies.
Collapse
Affiliation(s)
- Khursheed Ul Islam
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Saleem Anwar
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Ayyub A. Patel
- Department of Clinical Biochemistry, College of Medicine, King Khalid University, Abha 62529, Saudi Arabia
| | | | | | - Md Iqbal Azmi
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Tanveer Ahmad
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Zeeshan Fatima
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, University of Bisha, Bisha 61922, Saudi Arabia
- Amity Institute of Biotechnology, Amity University Haryana, Manesar, Gurugram 122413, India
- Correspondence: (Z.F.); (J.I.)
| | - Jawed Iqbal
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
- Correspondence: (Z.F.); (J.I.)
| |
Collapse
|
9
|
Hepatitis C Virus-Lipid Interplay: Pathogenesis and Clinical Impact. Biomedicines 2023; 11:biomedicines11020271. [PMID: 36830808 PMCID: PMC9953247 DOI: 10.3390/biomedicines11020271] [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: 12/16/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/20/2023] Open
Abstract
Hepatitis C virus (HCV) infection represents the major cause of chronic liver disease, leading to a wide range of hepatic diseases, including cirrhosis and hepatocellular carcinoma. It is the leading indication for liver transplantation worldwide. In addition, there is a growing body of evidence concerning the role of HCV in extrahepatic manifestations, including immune-related disorders and metabolic abnormalities, such as insulin resistance and steatosis. HCV depends on its host cells to propagate successfully, and every aspect of the HCV life cycle is closely related to human lipid metabolism. The virus circulates as a lipid-rich particle, entering the hepatocyte via lipoprotein cell receptors. It has also been shown to upregulate lipid biosynthesis and impair lipid degradation, resulting in significant intracellular lipid accumulation (steatosis) and circulating hypocholesterolemia. Patients with chronic HCV are at increased risk for hepatic steatosis, dyslipidemia, and cardiovascular disease, including accelerated atherosclerosis. This review aims to describe different aspects of the HCV viral life cycle as it impacts host lipoproteins and lipid metabolism. It then discusses the mechanisms of HCV-related hepatic steatosis, hypocholesterolemia, and accelerated atherosclerosis.
Collapse
|
10
|
Schelbert S, Schindeldecker M, Drebber U, Witzel HR, Weinmann A, Dries V, Schirmacher P, Roth W, Straub BK. Lipid Droplet-Associated Proteins Perilipin 1 and 2: Molecular Markers of Steatosis and Microvesicular Steatotic Foci in Chronic Hepatitis C. Int J Mol Sci 2022; 23:ijms232415456. [PMID: 36555099 PMCID: PMC9778710 DOI: 10.3390/ijms232415456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/29/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
Chronic infection with hepatitis C (HCV) is a major risk factor in the development of cirrhosis and hepatocellular carcinoma. Lipid metabolism plays a major role in the replication and deposition of HCV at lipid droplets (LDs). We have demonstrated the importance of LD-associated proteins of the perilipin family in steatotic liver diseases. Using a large collection of 231 human liver biopsies with HCV, perilipins 1 and 2 have been localized to LDs of hepatocytes that correlate with the degree of steatosis and specific HCV genotypes, but not significantly with the HCV viral load. Perilipin 1- and 2-positive microvesicular steatotic foci were observed in 36% of HCV liver biopsies, and also in chronic hepatitis B, autoimmune hepatitis and mildly steatotic or normal livers, but less or none were observed in normal livers of younger patients. Microvesicular steatotic foci did not frequently overlap with glycogenotic/clear cell foci as determined by PAS stain in serial sections. Steatotic foci were detected in all liver zones with slight architectural disarrays, as demonstrated by immunohistochemical glutamine synthetase staining of zone three, but without elevated Ki67-proliferation rates. In conclusion, microvesicular steatotic foci are frequently found in chronic viral hepatitis, but the clinical significance of these foci is so far not clear.
Collapse
Affiliation(s)
- Selina Schelbert
- Institute of Pathology, University Medical Center Mainz, 55131 Mainz, Germany
- Institute of Pathology, University Hospital Wuerzburg, 97080 Wuerzburg, Germany
| | | | - Uta Drebber
- Institute of Pathology, University Clinic Cologne, 50931 Cologne, Germany
| | - Hagen Roland Witzel
- Institute of Pathology, University Medical Center Mainz, 55131 Mainz, Germany
| | - Arndt Weinmann
- Department of Internal Medicine, University Medical Center, 55131 Mainz, Germany
| | - Volker Dries
- Institute of Pathology, University Clinic Cologne, 50931 Cologne, Germany
| | - Peter Schirmacher
- Institute of Pathology, University Medical Center Heidelberg, 69120 Heidelberg, Germany
| | - Wilfried Roth
- Institute of Pathology, University Medical Center Mainz, 55131 Mainz, Germany
| | - Beate Katharina Straub
- Institute of Pathology, University Medical Center Mainz, 55131 Mainz, Germany
- Correspondence: ; Tel.: +49-6131-17-7307
| |
Collapse
|
11
|
Diaz O, Vidalain PO, Ramière C, Lotteau V, Perrin-Cocon L. What role for cellular metabolism in the control of hepatitis viruses? Front Immunol 2022; 13:1033314. [PMID: 36466918 PMCID: PMC9713817 DOI: 10.3389/fimmu.2022.1033314] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/02/2022] [Indexed: 11/26/2023] Open
Abstract
Hepatitis B, C and D viruses (HBV, HCV, HDV, respectively) specifically infect human hepatocytes and often establish chronic viral infections of the liver, thus escaping antiviral immunity for years. Like other viruses, hepatitis viruses rely on the cellular machinery to meet their energy and metabolite requirements for replication. Although this was initially considered passive parasitism, studies have shown that hepatitis viruses actively rewire cellular metabolism through molecular interactions with specific enzymes such as glucokinase, the first rate-limiting enzyme of glycolysis. As part of research efforts in the field of immunometabolism, it has also been shown that metabolic changes induced by viruses could have a direct impact on the innate antiviral response. Conversely, detection of viral components by innate immunity receptors not only triggers the activation of the antiviral defense but also induces in-depth metabolic reprogramming that is essential to support immunological functions. Altogether, these complex triangular interactions between viral components, innate immunity and hepatocyte metabolism may explain why chronic hepatitis infections progressively lead to liver inflammation and progression to cirrhosis, fibrosis and hepatocellular carcinoma (HCC). In this manuscript, we first present a global overview of known connections between the innate antiviral response and cellular metabolism. We then report known molecular mechanisms by which hepatitis viruses interfere with cellular metabolism in hepatocytes and discuss potential consequences on the innate immune response. Finally, we present evidence that drugs targeting hepatocyte metabolism could be used as an innovative strategy not only to deprive viruses of key metabolites, but also to restore the innate antiviral response that is necessary to clear infection.
Collapse
Affiliation(s)
- Olivier Diaz
- CIRI, Centre International de Recherche en Infectiologie, Team VIRal Infection, Metabolism and Immunity, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| | - Pierre-Olivier Vidalain
- CIRI, Centre International de Recherche en Infectiologie, Team VIRal Infection, Metabolism and Immunity, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| | - Christophe Ramière
- CIRI, Centre International de Recherche en Infectiologie, Team VIRal Infection, Metabolism and Immunity, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
- Laboratoire de Virologie, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
| | - Vincent Lotteau
- CIRI, Centre International de Recherche en Infectiologie, Team VIRal Infection, Metabolism and Immunity, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| | - Laure Perrin-Cocon
- CIRI, Centre International de Recherche en Infectiologie, Team VIRal Infection, Metabolism and Immunity, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| |
Collapse
|
12
|
Mofed D, Sabet S, Baiomy AA, Salem TZ. The Transgene Expression of the Immature Form of the HCV Core Protein (C191) and the LncRNA MEG3 Increases Apoptosis in HepG2 Cells. Curr Issues Mol Biol 2022; 44:3632-3647. [PMID: 36005145 PMCID: PMC9406719 DOI: 10.3390/cimb44080249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 11/16/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) are regulated in cancer cells, including lncRNA MEG3, which is downregulated in Hepatocellular Carcinoma (HCC). In addition, hepatitis C virus (HCV) core proteins are known to dysregulate important cellular pathways that are linked to HCC development. In this study, we were interested in evaluating the overexpression of lncRNA MEG3, either alone or in combination with two forms of HCV core protein (C173 and C191) in HepG2 cells. Cell viability was assessed by MTT assay. Transcripts' levels of key genes known to be regulated in HCC, such as p53, DNMT1, miRNA152, TGF-b, and BCL-2, were measured by qRT-PCR. Protein expression levels of caspase-3 and MKI67 were determined by immunocytochemistry and apoptosis assays. The co-expression of lncRNA MEG3 and C191 resulted in a marked increase and accumulation of dead cells and a reduction in cell viability. In addition, a marked increase in the expression of tumor suppressor genes (p53 and miRNA152), as well as a marked decrease in the expression of oncogenes (DNMT1, BCL2, and TGF-b), were detected. Moreover, apoptosis assay results revealed a significant increase in total apoptosis (early and late). Finally, immunocytochemistry results detected a significant increase in apoptotic marker caspase-3 and a decrease in tumor marker MKI67. In this study, transgene expression of C191 and lncRNA MEG3 showed induction in apoptosis in HepG2 cells greater than the expression of each one alone. These results suggest potential anticancer characteristics.
Collapse
Affiliation(s)
- Dina Mofed
- Molecular Biology and Virology Lab, Biomedical Sciences Program, Zewail City of Science and Technology, October Gardens, 6th of October City, Giza 12578, Egypt
- Zoology Graduate Program, Department of Zoology, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Salwa Sabet
- Department of Zoology, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Ahmed A. Baiomy
- Department of Zoology, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Tamer Z. Salem
- Molecular Biology and Virology Lab, Biomedical Sciences Program, Zewail City of Science and Technology, October Gardens, 6th of October City, Giza 12578, Egypt
- Department of Microbial Genetics, Agricultural Genetic Engineering Research Institute (AGERl), Agricultural Research Center (ARC), Giza 12619, Egypt
- National Biotechnology Network of Expertise (NBNE), Academy of Science Research and Technology (ASRT), Cairo 11334, Egypt
- Correspondence: ; Tel.: +20-1014114122
| |
Collapse
|
13
|
Jiang YQ, Lin JP. Recent progress in strategies for steroid production in yeasts. World J Microbiol Biotechnol 2022; 38:93. [PMID: 35441962 DOI: 10.1007/s11274-022-03276-7] [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] [Received: 01/31/2022] [Accepted: 03/24/2022] [Indexed: 10/18/2022]
Abstract
As essential structural molecules of fungal cell membrane, ergosterol is not only an important component of fungal growth and stress-resistance but also a key precursor for manufacturing steroid drugs of pharmaceutical or agricultural significance. So far, ergosterol biosynthesis in yeast has been elucidated elaborately, and efforts have been made to increase ergosterol production through regulation of ergosterol metabolism and storage. Furthermore, the same intermediates shared by yeasts and animals or plants make the construction of heterologous sterol pathways in yeast a promising approach to synthesize valuable steroids, such as phytosteroids and animal steroid hormones. During these challenging processes, several obstacles have arisen and been combated with great endeavors. This paper reviews recent research progress of yeast metabolic engineering for improving the production of ergosterol and heterologous steroids. The remaining tactics are also discussed.
Collapse
Affiliation(s)
- Yi-Qi Jiang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jian-Ping Lin
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
| |
Collapse
|
14
|
Luna-Cuadros MA, Chen HW, Hanif H, Ali MJ, Khan MM, Lau DTY. Risk of hepatocellular carcinoma after hepatitis C virus cure. World J Gastroenterol 2022; 28:96-107. [PMID: 35125821 PMCID: PMC8793019 DOI: 10.3748/wjg.v28.i1.96] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 07/12/2021] [Accepted: 12/25/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a significant cause of hepatocellular carcinoma (HCC). The direct-acting antivirals marked a new era of HCV therapy and are associated with greater than 95% cure rate. Successful treatment of chronic hepatitis C greatly reduces the risk of HCC. A proportion of patients, especially those with pre-existing cirrhosis, remain at risk for HCC despite sustained virologic response (SVR). Diabetes mellitus, hepatic steatosis, alcohol consumption and lack of fibrosis regression are associated with risks of HCC after HCV cure. Noninvasive modalities such as aspartate aminotransferase to platelet ratio index and fibrosis-4 index and transient elastography have been used to monitor hepatic fibrosis. More recently, various fibrosis scores have been combined with clinical parameters and other novel biomarkers to predict risks of HCC for patients who achieved SVR. These models still need to be validated and standardized prior to applying to routine clinical care.
Collapse
Affiliation(s)
- Maria Alejandra Luna-Cuadros
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Hao-Wei Chen
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Hira Hanif
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Mukarram Jamat Ali
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Muzammil Muhammad Khan
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Daryl Tan-Yeung Lau
- Liver Center, Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| |
Collapse
|
15
|
Glitscher M, Hildt E. Endosomal Cholesterol in Viral Infections - A Common Denominator? Front Physiol 2021; 12:750544. [PMID: 34858206 PMCID: PMC8632007 DOI: 10.3389/fphys.2021.750544] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/22/2021] [Indexed: 12/24/2022] Open
Abstract
Cholesterol has gained tremendous attention as an essential lipid in the life cycle of virtually all viruses. These seem to have developed manifold strategies to modulate the cholesterol metabolism to the side of lipid uptake and de novo synthesis. In turn, affecting the cholesterol homeostasis has emerged as novel broad-spectrum antiviral strategy. On the other hand, the innate immune system is similarly regulated by the lipid and stimulated by its derivatives. This certainly requires attention in the design of antiviral strategies aiming to decrease cellular cholesterol, as evidence accumulates that withdrawal of cholesterol hampers innate immunity. Secondly, there are exceptions to the rule of the abovementioned virus-induced metabolic shift toward cholesterol anabolism. It therefore is of interest to dissect underlying regulatory mechanisms, which we aimed for in this minireview. We further collected evidence for intracellular cholesterol concentrations being less important in viral life cycles as compared to the spatial distribution of the lipid. Various routes of cholesterol trafficking were found to be hijacked in viral infections with respect to organelle-endosome contact sites mediating cholesterol shuttling. Thus, re-distribution of cellular cholesterol in the context of viral infections requires more attention in ongoing research. As a final aim, a pan-antiviral treatment could be found just within the transport and re-adjustment of local cholesterol concentrations. Thus, we aimed to emphasize the importance of the regulatory roles the endosomal system fulfils herein and hope to stimulate research in this field.
Collapse
Affiliation(s)
| | - Eberhard Hildt
- Department of Virology, Paul-Ehrlich-Institute, Langen, Germany
| |
Collapse
|
16
|
Lipid droplets are beneficial for rabies virus replication by facilitating viral budding. J Virol 2021; 96:e0147321. [PMID: 34757839 DOI: 10.1128/jvi.01473-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rabies is an old zoonotic disease caused by rabies virus (RABV), but the pathogenic mechanism of RABV is still not completely understood. Lipid droplets have been reported to play a role in pathogenesis of several viruses. However, its role on RABV infection remains unclear. Here, we initially found that RABV infection upregulated lipid droplet (LD) production in multiple cells and mouse brains. After the treatment of atorvastatin, a specific inhibitor of LD, RABV replication in N2a cells decreased. Then we found that RABV infection could upregulate N-myc downstream regulated gene-1 (NDRG1), which in turn enhance the expression of diacylglycerol acyltransferase 1/2 (DGAT1/2). DGAT1/2 could elevate cellular triglycerides synthesis and ultimately promote intracellular LD formation. Furthermore, we found that RABV-M and RABV-G, which were mainly involved in the viral budding process, could colocalize with LDs, indicating that RABV might utilize LDs as a carrier to facilitate viral budding and eventually increase virus production. Taken together, our study reveals that lipid droplets are beneficial for RABV replication and their biogenesis is regulated via NDRG1-DGAT1/2 pathway, which provides novel potential targets for developing anti-RABV drugs. IMPORTANCE Lipid droplets have been proven to play an important role in viral infections, but its role in RABV infection has not yet been elaborated. Here, we find that RABV infection upregulates the generation of LDs by enhancing the expression of N-myc downstream regulated gene-1 (NDRG1). Then NDRG1 elevated cellular triglycerides synthesis by increasing the activity of diacylglycerol acyltransferase 1/2 (DGAT1/2), which promotes the biogenesis of LDs. RABV-M and RABV-G, which are the major proteins involved in viral budding, could utilize LDs as a carrier and transport to cell membrane, resulting in enhanced virus budding. Our findings will extend the knowledge of lipid metabolism in RABV infection and help to explore potential therapeutic targets for RABV.
Collapse
|
17
|
Wang L, Lin J, Yu J, Yang K, Sun L, Tang H, Pan L. Downregulation of Perilipin1 by the Immune Deficiency Pathway Leads to Lipid Droplet Reconfiguration and Adaptation to Bacterial Infection in Drosophila. THE JOURNAL OF IMMUNOLOGY 2021; 207:2347-2358. [PMID: 34588219 DOI: 10.4049/jimmunol.2100343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 08/26/2021] [Indexed: 11/19/2022]
Abstract
Lipid droplets (LDs), the highly dynamic intracellular organelles, are critical for lipid metabolism. Dynamic alterations in the configurations and functions of LDs during innate immune responses to bacterial infections and the underlying mechanisms, however, remain largely unknown. In this study, we trace the time-course morphology of LDs in fat bodies of Drosophila after transient bacterial infection. Detailed analysis shows that perilipin1 (plin1), a core gene involved in the regulation of LDs, is suppressed by the immune deficiency signaling, one major innate immune pathway in Drosophila During immune activation, downregulated plin1 promotes the enlargement of LDs, which in turn alleviates immune reaction-associated reactive oxygen species stress. Thus, the growth of LDs is likely an active adaptation to maintain redox homeostasis in response to immune deficiency activation. Therefore, our study provides evidence that plin1 serves as a modulator on LDs' reconfiguration in regulating infection-induced pathogenesis, and plin1 might be a potential therapeutic target for coordinating inflammation resolution and lipid metabolism.
Collapse
Affiliation(s)
- Lei Wang
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China.,The Center for Microbes, Development, and Health, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jiaxin Lin
- The Center for Microbes, Development, and Health, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Junjing Yu
- Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China; and
| | - Kaiyan Yang
- The Center for Microbes, Development, and Health, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Li Sun
- The Center for Microbes, Development, and Health, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Hong Tang
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China;
| | - Lei Pan
- The Center for Microbes, Development, and Health, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China; .,University of Chinese Academy of Sciences, Beijing, China.,Chinese Academy of Sciences Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
18
|
Monson EA, Trenerry AM, Laws JL, Mackenzie JM, Helbig KJ. Lipid droplets and lipid mediators in viral infection and immunity. FEMS Microbiol Rev 2021; 45:fuaa066. [PMID: 33512504 PMCID: PMC8371277 DOI: 10.1093/femsre/fuaa066] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/02/2020] [Indexed: 12/14/2022] Open
Abstract
Lipid droplets (LDs) contribute to key pathways important for the physiology and pathophysiology of cells. In a homeostatic view, LDs regulate the storage of neutral lipids, protein sequestration, removal of toxic lipids and cellular communication; however, recent advancements in the field show these organelles as essential for various cellular stress response mechanisms, including inflammation and immunity, with LDs acting as hubs that integrate metabolic and inflammatory processes. The accumulation of LDs has become a hallmark of infection, and is often thought to be virally driven; however, recent evidence is pointing to a role for the upregulation of LDs in the production of a successful immune response to viral infection. The fatty acids housed in LDs are also gaining interest due to the role that these lipid species play during viral infection, and their link to the synthesis of bioactive lipid mediators that have been found to have a very complex role in viral infection. This review explores the role of LDs and their subsequent lipid mediators during viral infections and poses a paradigm shift in thinking in the field, whereby LDs may play pivotal roles in protecting the host against viral infection.
Collapse
Affiliation(s)
- Ebony A Monson
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Alice M Trenerry
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Jay L Laws
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Karla J Helbig
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| |
Collapse
|
19
|
Rolt A, Talley DC, Park SB, Hu Z, Dulcey A, Ma C, Irvin P, Leek M, Wang AQ, Stachulski AV, Xu X, Southall N, Ferrer M, Liang TJ, Marugan JJ. Discovery and Optimization of a 4-Aminopiperidine Scaffold for Inhibition of Hepatitis C Virus Assembly. J Med Chem 2021; 64:9431-9443. [PMID: 34184537 DOI: 10.1021/acs.jmedchem.1c00696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The majority of FDA-approved HCV therapeutics target the viral replicative machinery. An automated high-throughput phenotypic screen identified several small molecules as potent inhibitors of hepatitis C virus replication. Here, we disclose the discovery and optimization of a 4-aminopiperidine (4AP) scaffold targeting the assembly stages of the HCV life cycle. The original screening hit (1) demonstrates efficacy in the HCVcc assay but does not show potency prior to or during viral replication. Colocalization and infectivity studies indicate that the 4AP chemotype inhibits the assembly and release of infectious HCV. Compound 1 acts synergistically with FDA-approved direct-acting antiviral compounds Telaprevir and Daclatasvir, as well as broad spectrum antivirals Ribavirin and cyclosporin A. Following an SAR campaign, several derivatives of the 4AP series have been identified with increased potency against HCV, reduced in vitro toxicity, as well as improved in vitro and in vivo ADME properties.
Collapse
Affiliation(s)
- Adam Rolt
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Daniel C Talley
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Seung Bum Park
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Zongyi Hu
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Andrés Dulcey
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Christopher Ma
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Parker Irvin
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Madeleine Leek
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Amy Q Wang
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Andrew V Stachulski
- The Robert Robinson Laboratories, Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, U.K
| | - Xin Xu
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Noel Southall
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Marc Ferrer
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - T Jake Liang
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Juan J Marugan
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| |
Collapse
|
20
|
Saraceni C, Birk J. A Review of Hepatitis B Virus and Hepatitis C Virus Immunopathogenesis. J Clin Transl Hepatol 2021; 9:409-418. [PMID: 34221927 PMCID: PMC8237136 DOI: 10.14218/jcth.2020.00095] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 02/21/2021] [Accepted: 04/22/2021] [Indexed: 12/13/2022] Open
Abstract
Despite the advances in therapy, hepatitis B virus (HBV) and hepatitis C virus (HCV) still represent a significant global health burden, both as major causes of cirrhosis, hepatocellular carcinoma, and death worldwide. HBV is capable of incorporating its covalently closed circular DNA into the host cell's hepatocyte genome, making it rather difficult to eradicate its chronic stage. Successful viral clearance depends on the complex interactions between the virus and host's innate and adaptive immune response. One encouraging fact on hepatitis B is the development and effective distribution of the HBV vaccine. This has significantly reduced the spread of this virus. HCV is a RNA virus with high mutagenic capacity, thus enabling it to evade the immune system and have a high rate of chronic progression. High levels of HCV heterogeneity and its mutagenic capacity have made it difficult to create an effective vaccine. The recent advent of direct acting antivirals has ushered in a new era in hepatitis C therapy. Sustained virologic response is achieved with DAAs in 85-99% of cases. However, this still leads to a large population of treatment failures, so further advances in therapy are still needed. This article reviews the immunopathogenesis of HBV and HCV, their properties contributing to host immune system avoidance, chronic disease progression, vaccine efficacy and limitations, as well as treatment options and common pitfalls of said therapy.
Collapse
Affiliation(s)
- Corey Saraceni
- Correspondence to: Corey Saraceni, University of Connecticut School of Medicine, Department of Medicine, Division of Gastroenterology and Hepatology, 263 Farmington Avenue, Farmington, CT 06030-8074, USA. Tel: +1-203-733-7408, Fax: +1-860-679-3159, E-mail:
| | | |
Collapse
|
21
|
Lumaquin D, Johns E, Montal E, Weiss JM, Ola D, Abuhashem A, White RM. An in vivo reporter for tracking lipid droplet dynamics in transparent zebrafish. eLife 2021; 10:e64744. [PMID: 34114952 PMCID: PMC8195600 DOI: 10.7554/elife.64744] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 05/14/2021] [Indexed: 01/22/2023] Open
Abstract
Lipid droplets are lipid storage organelles found in nearly all cell types from adipocytes to cancer cells. Although increasingly implicated in disease, current methods to study lipid droplets in vertebrate models rely on static imaging or the use of fluorescent dyes, limiting investigation of their rapid in vivo dynamics. To address this, we created a lipid droplet transgenic reporter in whole animals and cell culture by fusing tdTOMATO to Perilipin-2 (PLIN2), a lipid droplet structural protein. Expression of this transgene in transparent casper zebrafish enabled in vivo imaging of adipose depots responsive to nutrient deprivation and high-fat diet. Simultaneously, we performed a large-scale in vitro chemical screen of 1280 compounds and identified several novel regulators of lipolysis in adipocytes. Using our Tg(-3.5ubb:plin2-tdTomato) zebrafish line, we validated several of these novel regulators and revealed an unexpected role for nitric oxide in modulating adipocyte lipid droplets. Similarly, we expressed the PLIN2-tdTOMATO transgene in melanoma cells and found that the nitric oxide pathway also regulated lipid droplets in cancer. This model offers a tractable imaging platform to study lipid droplets across cell types and disease contexts using chemical, dietary, or genetic perturbations.
Collapse
Affiliation(s)
- Dianne Lumaquin
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD ProgramNew YorkUnited States
| | - Eleanor Johns
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| | - Emily Montal
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| | - Joshua M Weiss
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD ProgramNew YorkUnited States
| | - David Ola
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| | - Abderhman Abuhashem
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD ProgramNew YorkUnited States
- Developmental Biology Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| | - Richard M White
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| |
Collapse
|
22
|
Wu K, Fan S, Zou L, Zhao F, Ma S, Fan J, Li X, Zhao M, Yan H, Chen J. Molecular Events Occurring in Lipophagy and Its Regulation in Flaviviridae Infection. Front Microbiol 2021; 12:651952. [PMID: 34093468 PMCID: PMC8175637 DOI: 10.3389/fmicb.2021.651952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 04/21/2021] [Indexed: 12/17/2022] Open
Abstract
Diseases caused by Flaviviridae have a wide global and economic impact due to high morbidity and mortality. Flaviviridae infection usually leads to severe, acute or chronic diseases, such as liver injury and liver cancer resulting from hepatitis C virus (HCV) infection, dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS) caused by dengue virus (DENV). Given the highly complex pathogenesis of Flaviviridae infections, they are still not fully understood at present. Accumulating evidence suggests that host autophagy is disrupted to regulate the life cycle of Flaviviridae. Organelle-specific autophagy is able to selectively target different organelles for quality control, which is essential for regulating cellular homeostasis. As an important sub process of autophagy, lipophagy regulates lipid metabolism by targeting lipid droplets (LDs) and is also closely related to the infection of a variety of pathogenic microorganisms. In this review, we briefly understand the LDs interaction relationship with Flaviviridae infection, outline the molecular events of how lipophagy occurs and the related research progress on the regulatory mechanisms of lipophagy in Flaviviridae infection. Exploring the crosstalk between viral infection and lipophagy induced molecular events may provide new avenues for antiviral therapy.
Collapse
Affiliation(s)
- Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Linke Zou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Feifan Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Shengming Ma
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Jindai Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Huichao Yan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| |
Collapse
|
23
|
Hepatitis C Virus Uses Host Lipids to Its Own Advantage. Metabolites 2021; 11:metabo11050273. [PMID: 33925362 PMCID: PMC8145847 DOI: 10.3390/metabo11050273] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/11/2021] [Accepted: 04/23/2021] [Indexed: 02/06/2023] Open
Abstract
Lipids and lipoproteins constitute indispensable components for living not only for humans. In the case of hepatitis C virus (HCV), the option of using the products of our lipid metabolism is “to be, or not to be”. On the other hand, HCV infection, which is the main cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma, exerts a profound influence on lipid and lipoprotein metabolism of the host. The consequences of this alternation are frequently observed as hypolipidemia and hepatic steatosis in chronic hepatitis C (CHC) patients. The clinical relevance of these changes reflects the fact that lipids and lipoprotein play a crucial role in all steps of the life cycle of HCV. The virus circulates in the bloodstream as a highly lipidated lipo-viral particle (LVP) that defines HCV hepatotropism. Thus, strict relationships between lipids/lipoproteins and HCV are indispensable for the mechanism of viral entry into hepatocytes, viral replication, viral particles assembly and secretion. The purpose of this review is to summarize the tricks thanks to which HCV utilizes host lipid metabolism to its own advantage.
Collapse
|
24
|
Galli A, Ramirez S, Bukh J. Lipid Droplets Accumulation during Hepatitis C Virus Infection in Cell-Culture Varies among Genotype 1-3 Strains and Does Not Correlate with Virus Replication. Viruses 2021; 13:389. [PMID: 33671086 PMCID: PMC7999684 DOI: 10.3390/v13030389] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 12/26/2022] Open
Abstract
Liver steatosis is a common complication of chronic hepatitis C virus (HCV) infection, which can result in accelerated liver fibrosis development, especially in patients infected with genotype 3a. The precise mechanisms of HCV-induced liver steatosis remain unclear, but it is often posited that increased intracellular lipid accumulation is the underlying cause of steatosis. To study experimentally how HCV infection in human liver derived cells by different genotypes and subtypes might affect lipid accumulation, we performed detailed cytofluorimetric and microscopy analyses of intracellular lipid droplets (LDs) in relation to the viral Core and to cell endoplasmic reticulum proteins. Following culture infection with HCV genotype 1a, 2a, 2b, 2c, and 3a strains, we found variable levels of intracellular LDs accumulation, associated to the infecting strain rather than to the specific genotype. Although two genotype 3a strains showed high levels of lipid accumulation, as previously observed, some strains of other genotypes displayed a similar phenotype. Moreover, the analyses of LDs size, number, and shape indicated that the apparent increase in lipid accumulation is due to an increase in the overall number rather than in the size of droplets. Finally, differences in total lipid content across genotypes did not correlate to differences in Core distribution nor Core levels. In conclusion, our study provides a quantitative in-depth analysis of the effect of HCV infection on LDs accumulation in cell-culture.
Collapse
Affiliation(s)
- Andrea Galli
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, 2650 Hvidovre, Denmark; (A.G.); (S.R.)
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Santseharay Ramirez
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, 2650 Hvidovre, Denmark; (A.G.); (S.R.)
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, 2650 Hvidovre, Denmark; (A.G.); (S.R.)
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| |
Collapse
|
25
|
de la Rosa Rodriguez MA, Deng L, Gemmink A, van Weeghel M, Aoun ML, Warnecke C, Singh R, Borst JW, Kersten S. Hypoxia-inducible lipid droplet-associated induces DGAT1 and promotes lipid storage in hepatocytes. Mol Metab 2021; 47:101168. [PMID: 33465519 PMCID: PMC7881268 DOI: 10.1016/j.molmet.2021.101168] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 12/26/2022] Open
Abstract
Objective Storage of triglycerides in lipid droplets is governed by a set of lipid droplet-associated proteins. One of these lipid droplet-associated proteins, hypoxia-inducible lipid droplet-associated (HILPDA), was found to impair lipid droplet breakdown in macrophages and cancer cells by inhibiting adipose triglyceride lipase. Here, we aimed to better characterize the role and mechanism of action of HILPDA in hepatocytes. Methods We performed studies in HILPDA-deficient and HILPDA-overexpressing liver cells, liver slices, and mice. The functional role and physical interactions of HILPDA were investigated using a variety of biochemical and microscopic techniques, including real-time fluorescence live-cell imaging and Förster resonance energy transfer-fluorescence lifetime imaging microscopy (FRET-FLIM). Results Levels of HILPDA were markedly induced by fatty acids in several hepatoma cell lines. Hepatocyte-specific deficiency of HILPDA in mice modestly but significantly reduced hepatic triglycerides in mice with non-alcoholic steatohepatitis. Similarly, deficiency of HILPDA in mouse liver slices and primary hepatocytes reduced lipid storage and accumulation of fluorescently-labeled fatty acids in lipid droplets, respectively, which was independent of adipose triglyceride lipase. Fluorescence microscopy showed that HILPDA partly colocalizes with lipid droplets and with the endoplasmic reticulum, is especially abundant in perinuclear areas, and mainly associates with newly added fatty acids. Real-time fluorescence live-cell imaging further revealed that HILPDA preferentially localizes to lipid droplets that are being remodeled. Overexpression of HILPDA in liver cells increased the activity of diacylglycerol acyltransferases (DGAT) and DGAT1 protein levels, concurrent with increased lipid storage. Confocal microscopy coupled to FRET-FLIM analysis demonstrated that HILPDA physically interacts with DGAT1 in living liver cells. The stimulatory effect of HILPDA on lipid storage via DGAT1 was corroborated in adipocytes. Conclusions Our data indicate that HILPDA physically interacts with DGAT1 and increases DGAT activity. Our findings suggest a novel regulatory mechanism by which fatty acids promote triglyceride synthesis and storage. HILPDA expression is induced by fatty acids in hepatoma cells. HILPDA deficiency modestly decreases liver triglyceride storage in mice with NASH. HILPDA preferentially associates with newly synthesized lipid droplets and active lipid droplets. HILPDA promotes lipid storage at least in part independently of ATGL. HILPDA physically interacts and induces DGAT1.
Collapse
Affiliation(s)
- Montserrat A de la Rosa Rodriguez
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, Wageningen, 6708 WE, the Netherlands
| | - Lei Deng
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, Wageningen, 6708 WE, the Netherlands
| | - Anne Gemmink
- Department of Nutrition and Movement Sciences, Maastricht University Medical Center+, Maastricht, 6200 MD, the Netherlands
| | - Michel van Weeghel
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, 1105 AZ, the Netherlands
| | - Marie Louise Aoun
- Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer 505D, Bronx, NY, 10461, USA
| | - Christina Warnecke
- Department of Nephrology and Hypertension, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Rajat Singh
- Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer 505D, Bronx, NY, 10461, USA
| | - Jan Willem Borst
- Laboratory of Biochemistry, Microspectroscopy Research Facility, Wageningen University, Stippeneng 4, Wageningen, 6708 WE, the Netherlands
| | - Sander Kersten
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, Wageningen, 6708 WE, the Netherlands.
| |
Collapse
|
26
|
Shimotohno K. HCV Assembly and Egress via Modifications in Host Lipid Metabolic Systems. Cold Spring Harb Perspect Med 2021; 11:cshperspect.a036814. [PMID: 32122916 PMCID: PMC7778218 DOI: 10.1101/cshperspect.a036814] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hepatitis C virus (HCV) proliferates by hijacking the host lipid machinery. In vitro replication systems revealed many aspects of the virus life cycle; in particular, viral utilization of host lipid metabolism during HCV proliferation. HCV interacts with lipid droplets (LDs) before starting the process of virus capsid formation at the lipid-rich endoplasmic reticulum (ER) membrane compartment. HCV buds into the ER via lipoprotein assembly and secretion. Exchangeable apolipoproteins, represented by apolipoprotein E (apoE), play pivotal roles in enhancing HCV-specific infectivity. HCV virions are likely to interact with other lipoproteins circulating in blood vessels and incorporate apolipoproteins as well as lipids. This review focuses on virus assembly and egress by briefly describing the recent advances in this area.
Collapse
|
27
|
Abstract
Liver cancer is a global problem and hepatocellular carcinoma (HCC) accounts for about 85% of this cancer. In the USA, etiologies and risk factors for HCC include chronic hepatitis C virus (HCV) infection, diabetes, non-alcoholic steatohepatitis (NASH), obesity, excessive alcohol drinking, exposure to tobacco smoke, and genetic factors. Chronic HCV infection appears to be associated with about 30% of HCC. Chronic HCV infection induces multistep changes in liver, involving metabolic disorders, steatosis, cirrhosis and HCC. Liver carcinogenesis requires initiation of neoplastic clones, and progression to clinically diagnose malignancy. Tumor progression associates with profound exhaustion of tumor-antigen-specific CD8+T cells, and accumulation of PD-1hi CD8+T cells and Tregs. In this chapter, we provide a brief description of HCV and environmental/genetic factors, immune regulation, and highlight mechanisms of HCV associated HCC. We also underscore HCV treatment and recent paradigm of HCC progression, highlighted the current treatment and potential future therapeutic opportunities.
Collapse
|
28
|
Liu B, Gao TT, Fu XY, Xu ZH, Ren H, Zhao P, Qi ZT, Qin ZL. PTEN Lipid Phosphatase Activity Enhances Dengue Virus Production through Akt/FoxO1/Maf1 Signaling. Virol Sin 2020; 36:412-423. [PMID: 33044659 DOI: 10.1007/s12250-020-00291-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 07/31/2020] [Indexed: 01/19/2023] Open
Abstract
Dengue virus (DENV) is an arthropod-borne viral pathogen and a global health burden. Knowledge of the DENV-host interactions that mediate virus pathogenicity remains limited. Host lipid metabolism is hijacked by DENV for virus replication in which lipid droplets (LDs) play a key role during the virus lifecycle. In this study, we reveal a novel role for phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in LDs-mediated DENV infection. We demonstrate that PTEN expression is downregulated upon DENV infection through post-transcriptional regulation and, in turn, PTEN overexpression enhances DENV replication. PTEN lipid phosphatase activity was found to decrease cellular LDs area and number through Akt/FoxO1/Maf1 signaling, which, together with autophagy, enhanced DENV replication and virus production. We therefore provide mechanistic insight into the interaction between lipid metabolism and the DENV replication cycle.
Collapse
Affiliation(s)
- Bin Liu
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China
| | - Ting-Ting Gao
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China.,Department of Nephrology, The Air Force Hospital from Northern Theater of PLA, Shenyang 110042, China
| | - Xiao-Yu Fu
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China
| | - Zhen-Hao Xu
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China
| | - Hao Ren
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China
| | - Ping Zhao
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China
| | - Zhong-Tian Qi
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China.
| | - Zhao-Ling Qin
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, Shanghai, 200433, China.
| |
Collapse
|
29
|
Park SB, Boyer A, Hu Z, Le D, Liang TJ. Discovery and characterization of a novel HCV inhibitor targeting the late stage of HCV life cycle. Antivir Ther 2020; 24:371-381. [PMID: 30880685 DOI: 10.3851/imp3303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND Currently approved anti-HCV drugs, the direct-acting antivirals (DAAs), are highly effective and target the viral RNA replication stage of the HCV life cycle. Due to high mutation rate of HCV, drug resistant variants can arise during DAA monotherapy. Thus, a combination of DAAs is necessary to achieve a high response rate. Novel HCV inhibitors targeting the HCV late stage such as assembly and release may further improve combination therapy with the DAAs. Here we characterize one late stage-targeting candidate compound, 6-(4-chloro-3-methylphenoxy)-pyridin-3-amine (MLS000833705). METHODS We treated HCV-infected cells with MLS000833705 and other HCV inhibitors and examined HCV RNA and infectious titres. We evaluated the colocalization of HCV core and lipid droplets by confocal microscopy. We performed HCV core-proteinase K digestion assay and several lipid assays to study the mechanism of MLS000833705. RESULTS We showed that MLS000833705 decreased extracellular HCV RNA levels more than intracellular HCV RNA levels in HCV infectious cell culture. Similarly, MLS000833705 reduced infectious HCV titres substantially more in the culture supernatant than intracellularly. Confocal microscopy showed that MLS000833705 did not affect the colocalization of HCV core protein with cellular lipid droplets where HCV assembles. HCV core-proteinase K digestion assay showed that MLS000833705 inhibited the envelopment of HCV capsid. CONCLUSIONS Our study demonstrates that MLS000833705 is a late-stage HCV inhibitor targeting HCV morphogenesis and maturation. Therefore, MLS000833705 can be used as a molecular probe to study HCV maturation and secretion and possibly guide development of a new class of HCV antivirals.
Collapse
Affiliation(s)
- Seung Bum Park
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Audrey Boyer
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Zongyi Hu
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Derek Le
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - T Jake Liang
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
30
|
Coleman RA. The "discovery" of lipid droplets: A brief history of organelles hidden in plain sight. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158762. [PMID: 32622088 DOI: 10.1016/j.bbalip.2020.158762] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 06/24/2020] [Accepted: 06/29/2020] [Indexed: 12/14/2022]
Abstract
Mammalian lipid droplets (LDs), first described as early as the 1880s, were virtually ignored for more than 100 years. Between 1991 and the early 2000s, however, a series of discoveries and conceptual breakthroughs led to a resurgent interest in obesity as a disease, in the metabolism of intracellular triacylglycerol (TAG), and in the physical locations of LDs as cellular structures with their associated proteins. Insights included the recognition that obesity underlies major chronic diseases, that appetite is hormonally controlled, that hepatic steatosis is not a benign finding, and that diabetes might fundamentally be a disorder of lipid metabolism. In this brief review, I describe the metamorphosis of LDs from overlooked globs of stored fat to dynamic organelles that control insulin resistance, mitochondrial oxidation, and viral replication.
Collapse
Affiliation(s)
- Rosalind A Coleman
- Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States of America.
| |
Collapse
|
31
|
Bhardwaj T, Saumya KU, Kumar P, Sharma N, Gadhave K, Uversky VN, Giri R. Japanese encephalitis virus - exploring the dark proteome and disorder-function paradigm. FEBS J 2020; 287:3751-3776. [PMID: 32473054 DOI: 10.1111/febs.15427] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/26/2020] [Accepted: 05/26/2020] [Indexed: 12/11/2022]
Abstract
Japanese encephalitis virus (JEV) is one of the major causes of viral encephalitis all around the globe. Approximately 3 billion people in endemic areas are at risk of Japanese encephalitis. To develop a wholistic understanding of the viral proteome, it is important to investigate both its ordered and disordered proteins. However, the functional and structural significance of disordered regions in the JEV proteome has not been systematically investigated as of yet. To fill this gap, we used here a set of bioinformatics tools to analyze the JEV proteome for the predisposition of its proteins for intrinsic disorder and for the presence of the disorder-based binding regions (also known as molecular recognition features, MoRFs). We also analyzed all JEV proteins for the presence of the probable nucleic acid-binding (DNA and RNA) sites. The results of these computational studies are experimentally validated using JEV capsid protein as an illustrative example. In agreement with bioinformatic analysis, we found that the N-terminal region of the JEV capsid (residues 1-30) is intrinsically disordered. We showed that this region is characterized by the temperature response typical for highly disordered proteins. Furthermore, we have experimentally shown that this disordered N-terminal domain of a capsid protein has a noticeable 'gain-of-structure' potential. In addition, using DOPS liposomes, we demonstrated the presence of pronounced membrane-mediated conformational changes in the N-terminal region of JEV capsid. In our view, this disorder-centric analysis would be helpful for a better understanding of the JEV pathogenesis.
Collapse
Affiliation(s)
- Taniya Bhardwaj
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| | - Kumar Udit Saumya
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| | - Prateek Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| | - Nitin Sharma
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| | - Kundlik Gadhave
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| | - Vladimir N Uversky
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.,Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center 'Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences', Russia
| | - Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, India
| |
Collapse
|
32
|
Liu D, Ndongwe TP, Puray-Chavez M, Casey MC, Izumi T, Pathak VK, Tedbury PR, Sarafianos SG. Effect of P-body component Mov10 on HCV virus production and infectivity. FASEB J 2020; 34:9433-9449. [PMID: 32496609 DOI: 10.1096/fj.201800641r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 03/28/2020] [Accepted: 05/04/2020] [Indexed: 12/11/2022]
Abstract
Mov10 is a processing body (P-body) protein and an interferon-stimulated gene that can affect replication of retroviruses, hepatitis B virus, and hepatitis C virus (HCV). The mechanism of HCV inhibition by Mov10 is unknown. Here, we investigate the effect of Mov10 on HCV infection and determine the virus life cycle steps affected by changes in Mov10 overexpression. Mov10 overexpression suppresses HCV RNA in both infectious virus and subgenomic replicon systems. Additionally, Mov10 overexpression decreases the infectivity of released virus, unlike control P-body protein DCP1a that has no effect on HCV RNA production or infectivity of progeny virus. Confocal imaging of uninfected cells shows endogenous Mov10 localized at P-bodies. However, in HCV-infected cells, Mov10 localizes in circular structures surrounding cytoplasmic lipid droplets with NS5A and core protein. Mutagenesis experiments show that the RNA binding activity of Mov10 is required for HCV inhibition, while its P-body localization, helicase, and ATP-binding functions are not required. Unexpectedly, endogenous Mov10 promotes HCV replication, as CRISPR-Cas9-based Mov10 depletion decreases HCV replication and infection levels. Our data reveal an important and complex role for Mov10 in HCV replication, which can be perturbed by excess or insufficient Mov10.
Collapse
Affiliation(s)
- Dandan Liu
- Christopher Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Tanyaradzwa P Ndongwe
- Christopher Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Maritza Puray-Chavez
- Christopher Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Mary C Casey
- Christopher Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Taisuke Izumi
- Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute-Frederick, Frederick, MD, USA
| | - Vinay K Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute-Frederick, Frederick, MD, USA
| | - Philip R Tedbury
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| |
Collapse
|
33
|
Raja AM, Ciociola E, Ahmad IN, Dar FS, Naqvi SMS, Moaeen-ud-Din M, Raja GK, Romeo S, Mancina RM. Genetic Susceptibility to Chronic Liver Disease in Individuals from Pakistan. Int J Mol Sci 2020; 21:ijms21103558. [PMID: 32443539 PMCID: PMC7278956 DOI: 10.3390/ijms21103558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 02/07/2023] Open
Abstract
Chronic liver disease, with viral or non-viral etiology, is endemic in many countries and is a growing burden in Asia. Among the Asian countries, Pakistan has the highest prevalence of chronic liver disease. Despite this, the genetic susceptibility to chronic liver disease in this country has not been investigated. We performed a comprehensive analysis of the most robustly associated common genetic variants influencing chronic liver disease in a cohort of individuals from Pakistan. A total of 587 subjects with chronic liver disease and 68 healthy control individuals were genotyped for the HSD17B13 rs7261356, MBOAT7 rs641738, GCKR rs1260326, PNPLA3 rs738409, TM6SF2 rs58542926 and PPP1R3B rs4841132 variants. The variants distribution between case and control group and their association with chronic liver disease were tested by chi-square and binary logistic analysis, respectively. We report for the first time that HSD17B13 variant results in a 50% reduced risk for chronic liver disease; while MBOAT7; GCKR and PNPLA3 variants increase this risk by more than 35% in Pakistani individuals. Our genetic analysis extends the protective role of the HSD17B13 variant against chronic liver disease and disease risk conferred by the MBOAT7; GCKR and PNPLA3 variants in the Pakistani population.
Collapse
Affiliation(s)
- Asad Mehmood Raja
- University Institute of Biochemistry and Biotechnology, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, Rawalpindi 46300, Pakistan; (A.M.R.); (S.M.S.N.); (G.K.R.)
| | - Ester Ciociola
- Department of Molecular and Clinical Medicine, The Sahlgrenska Academy at the University of Gothenburg, Wallenberg Laboratory, 413 45 Gothenburg, Sweden;
| | - Imran Nazir Ahmad
- Department of Pathology and Laboratory Medicine, Shifa International Hospitals Ltd., Islamabad 44790, Pakistan;
| | - Faisal Saud Dar
- Liver Transplantation, Hepatobiliary and Pancreatic Services Unit, Shifa International Hospitals Ltd., Islamabad 44790, Pakistan;
| | - Syed Muhammad Saqlan Naqvi
- University Institute of Biochemistry and Biotechnology, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, Rawalpindi 46300, Pakistan; (A.M.R.); (S.M.S.N.); (G.K.R.)
| | - Muhammad Moaeen-ud-Din
- Department of Animal Breeding and Genetics/National Center for Livestock Breeding, Genetics & Genomics, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, Rawalpindi 46300, Pakistan;
| | - Ghazala Kaukab Raja
- University Institute of Biochemistry and Biotechnology, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, Rawalpindi 46300, Pakistan; (A.M.R.); (S.M.S.N.); (G.K.R.)
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, The Sahlgrenska Academy at the University of Gothenburg, Wallenberg Laboratory, 413 45 Gothenburg, Sweden;
- Department of Cardiology, Sahlgrenska University Hospital, 413 45 Gothenburg, Sweden
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, 88100 Catanzaro, Italy
- Correspondence: (S.R.); (R.M.M.); Tel.: +46-(0)313-426-735 (S.R.); +46-(0)31342186 (R.M.M.)
| | - Rosellina Margherita Mancina
- Department of Molecular and Clinical Medicine, The Sahlgrenska Academy at the University of Gothenburg, Wallenberg Laboratory, 413 45 Gothenburg, Sweden;
- Correspondence: (S.R.); (R.M.M.); Tel.: +46-(0)313-426-735 (S.R.); +46-(0)31342186 (R.M.M.)
| |
Collapse
|
34
|
Hsu CS, Liu WL, Li Q, Lowey B, Hertz L, Chao YC, Liang TJ, Chen DS, Kao JH. Hepatitis C virus genotypes 1-3 infections regulate lipogenic signaling and suppress cholesterol biosynthesis in hepatocytes. J Formos Med Assoc 2020; 119:1382-1395. [PMID: 32284164 DOI: 10.1016/j.jfma.2020.03.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/18/2020] [Accepted: 03/23/2020] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Patients with different hepatitis C virus (HCV) genotype infections are associated with varying metabolic disorders. Although alteration of lipid metabolism has been confirmed as a virus-induced metabolic derangement in chronic hepatitis C patients, the impact of various HCV genotypes on hepatic cholesterol metabolism remains elusive. In this study, we thus investigated the HCV genotype-specific lipogenic and cholesterol metabolism profiles in an in vitro cell culture system. METHODS We first conducted HCV cell culture system (HCVcc) assays by infecting Huh7.5.1 cells with multiple infection-competent HCV strains, including the genotype 2a JFH1 and JFH1-based intergenotypic recombinants 1b and 3a. We then examined the expression levels of various lipid and cholesterol-related genes. RESULTS The data showed that infection with individual HCV genotypes exerted unique gene expression regulatory effects on lipoproteins and cholesterol metabolism genes. Of note, all HCV strains suppressed cholesterol biosynthesis in hepatocytes through downregulating the expression of HMG-CoA reductase (HMGCR) and farnesyl-diphosphate farnesyltransferase 1 (FDFT1) - two essential enzymes for cholesterol biosynthesis. These HCV-mediated inhibitory effects could be reversed by treatment with sofosbuvir, a pangenotypic NS5B inhibitor. In addition, overexpression of HCV genotype 1b, 2a or 3a core protein significantly suppressed HMGCR mRNA transcription and translation, thus diminished cellular cholesterol biosynthesis. Nonetheless, the core protein had no effect on FDFT1 expression. CONCLUSION Although HCV infection regulates host lipid metabolism in a genotype-specific manner, its inhibition on hepatocellular cholesterogenic gene expression and total cholesterol biosynthesis is a common effect among HCV genotype 1b, 2a and 3a.
Collapse
Affiliation(s)
- Ching-Sheng Hsu
- Liver Diseases Research Center, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei, Taiwan; School of Post-Baccalaureate Chinese Medicine, Tzu Chi University, Hualien, Taiwan; Division of Gastroenterology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei, Taiwan
| | - Wei-Liang Liu
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Miaoli, Taiwan; Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Qisheng Li
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Brianna Lowey
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Laura Hertz
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - You-Chen Chao
- Division of Gastroenterology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei, Taiwan
| | - T Jake Liang
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ding-Shinn Chen
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Internal Medicine, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei, Taiwan; Genomics Research Center, Academia Sinica, Nankang, 11549, Taiwan
| | - Jia-Horng Kao
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Miaoli, Taiwan; Department of Internal Medicine, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Research, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei, Taiwan; Hepatitis Research Center, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei, Taiwan.
| |
Collapse
|
35
|
Chen F, Yin Y, Chua BT, Li P. CIDE family proteins control lipid homeostasis and the development of metabolic diseases. Traffic 2019; 21:94-105. [PMID: 31746121 DOI: 10.1111/tra.12717] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/03/2019] [Accepted: 11/15/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Feng‐Jung Chen
- Institute of Metabolism and Integrative Biology, the Human Phenome InstituteFudan University, and Zhongshan Hospital of Fudan University Shanghai China
| | - Yesheng Yin
- Institute of Metabolism and Integrative Biology, the Human Phenome InstituteFudan University, and Zhongshan Hospital of Fudan University Shanghai China
| | - Boon Tin Chua
- Institute of Metabolism and Integrative Biology, the Human Phenome InstituteFudan University, and Zhongshan Hospital of Fudan University Shanghai China
| | - Peng Li
- State Key Laboratory of Membrane Biology and Tsinghua‐Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life SciencesTsinghua University Beijing China
| |
Collapse
|
36
|
Dejgaard SY, Presley JF. Rab18 regulates lipolysis via Arf/GBF1 and adipose triglyceride lipase. Biochem Biophys Res Commun 2019; 520:526-531. [PMID: 31610914 DOI: 10.1016/j.bbrc.2019.10.069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 10/06/2019] [Indexed: 01/09/2023]
Abstract
Rab18 is a small GTPase associated with lipid droplets and other membranes. While it likely has multiple functions on lipid droplets, one proposed function is regulation of lipolysis. Previous work has concentrated on regulation of autophagy; however, in this study, we provide evidence that Rab18 plays a role upstream of the cytosolic lipolytic enzyme adipose triglyceride lipase (ATGL) and that recruitment of ATGL by Rab18 is mediated by elements of the Arf/GBF1 machinery. We find that Arf4-GFP is accumulated on the subset of lipid droplets associated with Rab18, and that this association is lost within 5 min upon treatment with 5 μg/ml of the drug brefeldin A, which targets GBF1 and other Sec7-domain containing Arf exchange factors. ATGL-GFP is also recruited to lipid droplets, but is lost more slowly after treatment with 5 μg/ml brefeldin A, with significant loss from lipid droplets after 1 h treatment, and almost complete loss from lipid droplets 4 h after brefeldin A treatment. Upon overexpression of the dominant negative GDP-locked cerulean-Rab18-S22 N, GFP-ATGL and Arf4 are lost from the surface of lipid droplets similarly to BFA treatment. This study establishes, for the first time, an essential role for Rab18 in recruiting ATGL to lipid droplets.
Collapse
Affiliation(s)
- Selma Yilmaz Dejgaard
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada; Department of Medical Biology, Near East University, Nicosia, Cyprus
| | - John F Presley
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada.
| |
Collapse
|
37
|
Transforming Growth Factor β Acts as a Regulatory Molecule for Lipogenic Pathways among Hepatitis C Virus Genotype-Specific Infections. J Virol 2019; 93:JVI.00811-19. [PMID: 31243135 DOI: 10.1128/jvi.00811-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 06/21/2019] [Indexed: 12/14/2022] Open
Abstract
Hepatitis C virus (HCV) infection promotes metabolic disorders, and the severity of lipogenic disease depends upon the infecting virus genotype. Here, we have examined HCV genotype 1-, 2-, or 3-specific regulation of lipid metabolism, involving transforming growth factor β (TGF-β)-regulated phospho-Akt (p-Akt) and peroxisome proliferator-activated receptor alpha (PPARα) axes. Since HCV core protein is one of the key players in metabolic regulation, we also examined its contribution in lipid metabolic pathways. The expression of regulatory molecules, TGF-β1/2, phospho-Akt (Ser473), PPARα, sterol regulatory element-binding protein 1 (SREBP-1), fatty acid synthase (FASN), hormone-sensitive lipase (HSL), and acyl dehydrogenases was analyzed in virus-infected hepatocytes. Interestingly, HCV genotype 3a exhibited much higher activation of TGF-β and p-Akt, with a concurrent decrease in PPARα expression and fatty acid oxidation. A significant and similar decrease in HSL, unlike in HCV genotype 1a, was observed with both genotypes 2a and 3a. Similar observations were made from ectopic expression of the core genomic region from each genotype. The key role of TGF-β was further verified using specific small interfering RNA (siRNA). Together, our results highlight a significant difference in TGF-β-induced activity for the HCV genotype 2a- or 3a-induced lipogenic pathway, exhibiting higher triglyceride synthesis and a decreased lipolytic mechanism. These results may help in therapeutic modalities for early treatment of HCV genotype-associated lipid metabolic disorders.IMPORTANCE Hepatic steatosis is a frequent complication associated with chronic hepatitis C virus (HCV) infection and is a key prognostic indicator for progression to fibrosis and cirrhosis. Several mechanisms are proposed for the development of steatosis, especially with HCV genotype 3a. Our observations suggest that transforming growth factor β (TGF-β) and peroxisome proliferator-activated receptor alpha (PPARα)-associated mechanistic pathways in hepatocytes infected with HCV genotype 2a and 3a differ from those in cells infected with genotype 1a. The results suggest that a targeted therapeutic approach for enhanced PPARα and lipolysis may reduce HCV genotype-associated lipid metabolic disorder in liver disease.
Collapse
|
38
|
Abstract
This review discusses the current state of the viral metabolism field and gaps in knowledge that will be important for future studies to investigate. We discuss metabolic rewiring caused by viruses, the influence of oncogenic viruses on host cell metabolism, and the use of viruses as guides to identify critical metabolic nodes for cancer anabolism. We also discuss the need for more mechanistic studies identifying viral proteins responsible for metabolic hijacking and for in vivo studies of viral-induced metabolic rewiring. Improved technologies for detailed metabolic measurements and genetic manipulation will lead to important discoveries over the next decade.
Collapse
Affiliation(s)
- Shivani K Thaker
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, 90095, USA
| | - James Ch'ng
- Department of Pediatrics, Division of Hematology/Oncology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA
| | - Heather R Christofk
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, 90095, USA.
- Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA, 90095, USA.
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, CA, 90095, USA.
| |
Collapse
|
39
|
Thiam AR, Dugail I. Lipid droplet-membrane contact sites - from protein binding to function. J Cell Sci 2019; 132:132/12/jcs230169. [PMID: 31209063 DOI: 10.1242/jcs.230169] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In the general context of an increasing prevalence of obesity-associated diseases, which follows changing paradigms in food consumption and worldwide use of industry-transformed foodstuffs, much attention has been given to the consequences of excessive fattening on health. Highly related to this clinical problem, studies at the cellular and molecular level are focused on the fundamental mechanism of lipid handling in dedicated lipid droplet (LD) organelles. This Review briefly summarizes how views on LD functions have evolved from those of a specialized intracellular compartment dedicated to lipid storage to exerting a more generalized role in the stress response. We focus on the current understanding of how proteins bind to LDs and determine their function, and on the new paradigms that have emerged from the discoveries of the multiple contact sites formed by LDs. We argue that elucidating the important roles of LD tethering to other cellular organelles allows for a better understanding of LD diversity and dynamics.
Collapse
Affiliation(s)
- Abdou Rachid Thiam
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, 75005 Paris, France
| | - Isabelle Dugail
- U1269 INSERM/Sorbonne Université, Nutriomics, Faculté de Médecine Pitié-Salpêtrière, 75013 Paris, France
| |
Collapse
|
40
|
USP15 Participates in Hepatitis C Virus Propagation through Regulation of Viral RNA Translation and Lipid Droplet Formation. J Virol 2019; 93:JVI.01708-18. [PMID: 30626683 DOI: 10.1128/jvi.01708-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 12/23/2018] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) utilizes cellular factors for efficient propagation. Ubiquitin is covalently conjugated to the substrate to alter its stability or to modulate signal transduction. In this study, we examined the importance of ubiquitination for HCV propagation. We found that inhibition of deubiquitinating enzymes (DUBs) or overexpression of nonspecific DUBs impaired HCV replication, suggesting that ubiquitination regulates HCV replication. To identify specific DUBs involved in HCV propagation, we set up RNA interference (RNAi) screening against DUBs and successfully identified ubiquitin-specific protease 15 (USP15) as a novel host factor for HCV propagation. Our studies showed that USP15 is involved in translation of HCV RNA and production of infectious HCV particles. In addition, deficiency of USP15 in human hepatic cell lines (Huh7 and Hep3B/miR-122 cells) but not in a nonhepatic cell line (293T cells) impaired HCV propagation, suggesting that USP15 participates in HCV propagation through the regulation of hepatocyte-specific functions. Moreover, we showed that loss of USP15 had no effect on innate immune responses in vitro and in vivo We also found that USP15-deficient Huh7 cells showed reductions in the amounts of lipid droplets (LDs), and the addition of palmitic acids restored the production of infectious HCV particles. Taken together, these data suggest that USP15 participates in HCV propagation by regulating the translation of HCV RNA and the formation of LDs.IMPORTANCE Although ubiquitination has been shown to play important roles in the HCV life cycle, the roles of deubiquitinating enzymes (DUBs), which cleave ubiquitin chains from their substrates, in HCV propagation have not been investigated. Here, we identified USP15 as a DUB regulating HCV propagation. USP15 showed no interaction with viral proteins and no participation in innate immune responses. Deficiency of USP15 in Huh7 cells resulted in suppression of the translation of HCV RNA and reduction in the amounts of lipid droplets, and the addition of fatty acids partially restored the production of infectious HCV particles. These data suggest that USP15 participates in HCV propagation in hepatic cells through the regulation of viral RNA translation and lipid metabolism.
Collapse
|
41
|
Akgöllü E, Akkız H. Association between hepatic steatosis and MTP gene -493G/T polymorphism in the patients with HCV genotype 1 infection. INFECTION GENETICS AND EVOLUTION 2019; 70:101-106. [PMID: 30790698 DOI: 10.1016/j.meegid.2019.02.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/11/2019] [Accepted: 02/18/2019] [Indexed: 01/07/2023]
Abstract
AIM Hepatitis C virus (HCV) affects approximately 250 million people worldwide. If patients are untreated, 80% of patients with chronic HCV develop liver failure, liver cirrhosis (LC), and hepatocellular carcinoma (HCC). HCV genotype 1 is the most prevalent among the infected individuals with HCV. Hepatic steatosis is known as accumulation of lipid molecules in hepatocytes, and its prevalence is approximately 55% in CHC infection. The reason of HCV-related hepatic steatosis in CHC infection is mainly HCV core protein. HCV core protein inhibits activities of microsomal triglyceride transfer protein (MTP) which is a lipid transfer protein expressed in the liver. The -493G/T polymorphism in the promoter region of MTP gene has been associated with HCV-related hepatic steatosis. This polymorphism in MTP gene influences MTP mRNA expression, therefore which might also affect lipid transfer. We evaluated the association between MTP gene polymorphism and the risk of HCV genotype 1-related hepatic steatosis. METHODS In the current study, MTP gene polymorphism was explored in 144 biopsy-proven chronic HCV genotype 1 patients by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS The results showed that there were no any difference between the steatosis and the non-steatosis groups for the allele and genotype frequencies of the -493G/T polymorphism (P > .05). Moreover, MTP genotypes (GG vs. TG + TT) were not associated with BMI, fibrosis stages and the levels of biochemical parameters. Additionally, there were statistically significant differences in the biochemical parameters including triglyceride, total cholesterol, LDL, VLDL levels between the two groups (P < .05). CONCLUSIONS In conclusion, the current study demonstrates for the first time that MTP gene -493G/T polymorphism has not a major effect on the risk of HCV genotype 1-related hepatic steatosis in Turkish population. Further studies are imperative to clarify the association of this polymorphism with HCV genotype 1 infection in HCV-related hepatic steatosis.
Collapse
Affiliation(s)
- Ersin Akgöllü
- Çukurova University, Faculty of Medicine, Department of Gastroenterology, Adana, Turkey.
| | - Hikmet Akkız
- Çukurova University, Faculty of Medicine, Department of Gastroenterology, Adana, Turkey
| |
Collapse
|
42
|
Lassen S, Grüttner C, Nguyen-Dinh V, Herker E. Perilipin-2 is critical for efficient lipoprotein and hepatitis C virus particle production. J Cell Sci 2019; 132:jcs.217042. [PMID: 30559250 DOI: 10.1242/jcs.217042] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 12/07/2018] [Indexed: 12/18/2022] Open
Abstract
In hepatocytes, PLIN2 is the major protein coating lipid droplets (LDs), an organelle the hepatitis C virus (HCV) hijacks for virion morphogenesis. We investigated the consequences of PLIN2 deficiency on LDs and on HCV infection. Knockdown of PLIN2 did not affect LD homeostasis, likely due to compensation by PLIN3, but severely impaired HCV particle production. PLIN2-knockdown cells had slightly larger LDs with altered protein composition, enhanced local lipase activity and higher β-oxidation capacity. Electron micrographs showed that, after PLIN2 knockdown, LDs and HCV-induced vesicular structures were tightly surrounded by ER-derived double-membrane sacs. Strikingly, the LD access for HCV core and NS5A proteins was restricted in PLIN2-deficient cells, which correlated with reduced formation of intracellular HCV particles that were less infectious and of higher density, indicating defects in maturation. PLIN2 depletion also reduced protein levels and secretion of ApoE due to lysosomal degradation, but did not affect the density of ApoE-containing lipoproteins. However, ApoE overexpression in PLIN2-deficient cells did not restore HCV spreading. Thus, PLIN2 expression is required for trafficking of core and NS5A proteins to LDs, and for formation of functional low-density HCV particles prior to ApoE incorporation.This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Susan Lassen
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany
| | - Cordula Grüttner
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany
| | - Van Nguyen-Dinh
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany
| | - Eva Herker
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany .,Institute of Virology, Philipps University Marburg, 35043 Marburg, Germany
| |
Collapse
|
43
|
Carvalho JR, Velosa J, Serejo F. Lipids, glucose and iron metabolic alterations in chronic hepatitis C after viral eradication - comparison of the new direct-acting antiviral agents with the old regimens. Scand J Gastroenterol 2018; 53:857-863. [PMID: 29779403 DOI: 10.1080/00365521.2018.1473486] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Hepatitis C virus (HCV) is a unique virus which interacts with cholesterol, iron and insulin metabolism. There is limited data on the effects of direct-acting antiviral agents (DAAs) on metabolic profiles. We aimed at evaluating the behavior of metabolic risk factors of chronically HCV-infected patients after sustained virologic response (SVR), comparing the outcomes with the new DAAs versus the old treatment regimen Peg-interferon ± ribavirin. METHODS A total of 178 patients who achieved SVR and completed one year of follow-up were prospectively included in this study: group 1 with 105 patients treated with DAAs and group 2 with 73 patients treated with old regimens. Outcomes included lipid, glucose and iron metabolism variation after SVR. RESULTS There was a significant increase in total cholesterol in both groups (group 1: p < .001, 95% CI: 0.41-0.78; group 2: p < .001, 95% CI: 0.24-0.69). Triglyceride levels significantly decreased (p = .015, 95% CI: -0.33-0.04) in group 1 and increased (p = .014, 95% CI: 0.07-0.59) in group 2. LDL levels increased in group 1 (p = .029, 95% CI: 0.05-0.88), but no significant variation was found in group 2. No significant variation in HDL, fast glucose and iron was seen in both groups. There was a significant increase of HOMA (p = .002, 95% CI: 0.17592-0.72317) only in group 2. Ferritin serum levels significantly decreased (p < .001, 95% CI:-138.3-74.4) in group 1 but no significant variation was found in group 2. CONCLUSION Patients who have achieved SVR may have increased risk of cardiovascular outcomes due to development of hyperlipidemia and insulin resistance.
Collapse
Affiliation(s)
- Joana Rita Carvalho
- a Department of Gastroenterology and Hepatology , North Lisbon Hospital Center, University of Lisbon , Lisboa , Portugal
| | - José Velosa
- a Department of Gastroenterology and Hepatology , North Lisbon Hospital Center, University of Lisbon , Lisboa , Portugal
| | - Fátima Serejo
- a Department of Gastroenterology and Hepatology , North Lisbon Hospital Center, University of Lisbon , Lisboa , Portugal
| |
Collapse
|
44
|
Gigi E, Lagopoulos VI, Bekiari E. Hepatocellular carcinoma occurrence in DAA-treated hepatitis C virus patients: Correlated or incidental? A brief review. World J Hepatol 2018; 10:595-602. [PMID: 30310537 PMCID: PMC6177564 DOI: 10.4254/wjh.v10.i9.595] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/25/2018] [Accepted: 06/30/2018] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) chronic infection induces liver fibrosis and cirrhosis but is also responsible for a significant portion of hepatocellular carcinoma (HCC) occurrence. Since it was recognized as a causative factor of chronic hepatitis, there have been multiple efforts towards viral eradication, leading to the first-generation HCV treatment that was based on interferon (IFN)-αand its analogs, mainly PEGylated interferon-α (PEG IFNα). Sustained virological response (SVR), defined as the absence of detectable RNA of HCV in blood serum for at least 24 wk after discontinuing the treatment, was accepted as a marker of viral clearance and was achieved in approximately one-half of patients treated with PEG IFNα regimens. Further research on the molecular biology of HCV gave rise to a new generation of drugs, the so-called direct antiviral agents (DAAs). DAA regimens, as implied by their name, interfere with the HCV genome or its products and have high SVR rates, over 90%, after just 12 wk of per os treatment. Although there are no questions about their efficacy or their universality, as they lack the contraindication for advanced liver disease that marks PEG IFNα, some reports of undesired oncologic outcomes after DAA treatment raised suspicions about possible interference of this treatment in HCC development. The purpose of the present review is to investigate the validity of these concerns based on recent clinical studies, summarize the mechanisms of action of DAAs and survey the updated data on HCV-induced liver carcinogenesis.
Collapse
Affiliation(s)
- Eleni Gigi
- 2nd Internal Medicine Department, Aristotle University Medical School, Hippokrateio General Hospital, Thessaloniki 54642, Greece
| | - Vasileios I Lagopoulos
- 5th Surgical Department, Aristotle University Medical School, Hippokrateio General Hospital, Thessaloniki 54642, Greece
| | - Eleni Bekiari
- 2nd Internal Medicine Department, Aristotle University Medical School, Hippokrateio General Hospital, Thessaloniki 54642, Greece
| |
Collapse
|
45
|
Martins AS, Martins IC, Santos NC. Methods for Lipid Droplet Biophysical Characterization in Flaviviridae Infections. Front Microbiol 2018; 9:1951. [PMID: 30186265 PMCID: PMC6110928 DOI: 10.3389/fmicb.2018.01951] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/02/2018] [Indexed: 01/14/2023] Open
Abstract
Lipid droplets (LDs) are intracellular organelles for neutral lipid storage, originated from the endoplasmic reticulum. They play an essential role in lipid metabolism and cellular homeostasis. In fact, LDs are complex organelles, involved in many more cellular processes than those initially proposed. They have been extensively studied in the context of LD-associated pathologies. In particular, LDs have emerged as critical for virus replication and assembly. Viruses from the Flaviviridae family, namely dengue virus (DENV), hepatitis C virus (HCV), West Nile virus (WNV), and Zika virus (ZIKV), interact with LDs to usurp the host lipid metabolism for their own viral replication and pathogenesis. In general, during Flaviviridae infections it is observed an increasing number of host intracellular LDs. Several viral proteins interact with LDs during different steps of the viral life cycle. The HCV core protein and DENV capsid protein, extensively interact with LDs to regulate their replication and assembly. Detailed studies of LDs in viral infections may contribute for the development of possible inhibitors of key steps of viral replication. Here, we reviewed different techniques that can be used to characterize LDs isolated from infected or non-infected cells. Microscopy studies have been commonly used to observe LDs accumulation and localization in infected cell cultures. Fluorescent dyes, which may affect LDs directly, are widely used to probe LDs but there are also approaches that do not require the use of fluorescence, namely stimulated Raman scattering, electron and atomic force microscopy-based approaches. These three are powerful techniques to characterize LDs morphology. Raman scattering microscopy allows studying LDs in a single cell. Electron and atomic force microscopies enable a better characterization of LDs in terms of structure and interaction with other organelles. Other biophysical techniques, such as dynamic light scattering and zeta potential are also excellent to characterize LDs in terms of size in a simple and fast way and test possible LDs interaction with viral proteins. These methodologies are reviewed in detail, in the context of viral studies.
Collapse
Affiliation(s)
- Ana S Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Ivo C Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Nuno C Santos
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| |
Collapse
|
46
|
Vallochi AL, Teixeira L, Oliveira KDS, Maya-Monteiro CM, Bozza PT. Lipid Droplet, a Key Player in Host-Parasite Interactions. Front Immunol 2018; 9:1022. [PMID: 29875768 PMCID: PMC5974170 DOI: 10.3389/fimmu.2018.01022] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/24/2018] [Indexed: 12/18/2022] Open
Abstract
Lipid droplets (lipid bodies, LDs) are dynamic organelles that have important roles in regulating lipid metabolism, energy homeostasis, cell signaling, membrane trafficking, and inflammation. LD biogenesis, composition, and functions are highly regulated and may vary according to the stimuli, cell type, activation state, and inflammatory environment. Increased cytoplasmic LDs are frequently observed in leukocytes and other cells in a number of infectious diseases. Accumulating evidence reveals LDs participation in fundamental mechanisms of host-pathogen interactions, including cell signaling and immunity. LDs are sources of eicosanoid production, and may participate in different aspects of innate signaling and antigen presentation. In addition, intracellular pathogens evolved mechanisms to subvert host metabolism and may use host LDs, as ways of immune evasion and nutrients source. Here, we review mechanisms of LDs biogenesis and their contributions to the infection progress, and discuss the latest discoveries on mechanisms and pathways involving LDs roles as regulators of the immune response to protozoan infection.
Collapse
Affiliation(s)
- Adriana Lima Vallochi
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | | | | | | | - Patricia T. Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| |
Collapse
|
47
|
Shimizu K, Soroida Y, Sato M, Hikita H, Kobayashi T, Endo M, Sato M, Gotoh H, Iwai T, Tateishi R, Koike K, Yatomi Y, Ikeda H. Eradication of hepatitis C virus is associated with the attenuation of steatosis as evaluated using a controlled attenuation parameter. Sci Rep 2018; 8:7845. [PMID: 29777191 PMCID: PMC5959884 DOI: 10.1038/s41598-018-26293-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 05/02/2018] [Indexed: 01/07/2023] Open
Abstract
Chronic hepatitis C virus (HCV) infection was shown to cause hepatic steatosis or suppression of serum lipid levels. However, little is known about the changes in hepatic steatosis following HCV eradication. We aimed to evaluate this issue using the controlled attenuation parameter (CAP), which was recently shown to provide a standardized non-invasive measure of hepatic steatosis. We enrolled 70 patients with chronic HCV infections and steatosis (CAP of over 248 dB/m) who had achieved a sustained viral response at 12 weeks after discontinuation of antiviral treatment using direct-acting antivirals (DAA). We then evaluated the state of hepatic steatosis before and after HCV eradication. We also investigated the changes in serum parameters such as cholesterol and glucose levels. The median value of CAP level decreased significantly after HCV eradication from 273 dB/m to 265 dB/m (P = 0.034). Also, LDL and HDL cholesterol levels increased significantly after HCV eradication (P = 0.002 and P = 0.027, respectively). In conclusion, a decrease in hepatic steatosis after HCV eradication with DAA was revealed in chronic hepatitis C patients with significant steatosis. Cancellation of the viral effect is a possible underlying cause of hepatic steatosis improvement and increase in HDL and LDL cholesterol levels.
Collapse
Affiliation(s)
- Kohei Shimizu
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Yoko Soroida
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Masaya Sato
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan. .,Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
| | - Hiromi Hikita
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Tamaki Kobayashi
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Momoe Endo
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Mamiko Sato
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroaki Gotoh
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomomi Iwai
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Ryosuke Tateishi
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kazuhiko Koike
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yutaka Yatomi
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Hitoshi Ikeda
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan.,Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
48
|
Zheng YP, Zhong XY, Huang YS, Zheng CB. HCBP6 Is Involved in the Development of Hepatic Steatosis Induced by High-Fat Diet and CCL4 in Rats. Ann Hepatol 2018; 17:511-518. [PMID: 29735802 DOI: 10.5604/01.3001.0011.7396] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION AND AIM Hepatitis C virus core-binding protein 6 (HCBP6) was previously found to be an hepatitis C virus corebinding protein, its biological function remains unclear. Our research aims to investigate the role of HCBP6 in the development of hepatic steatosis induced by high-fat diet and carbon tetrachloride (CCL4) in rats. MATERIAL AND METHODS Eighteen Wistar rats were randomly allocated into 3 groups: control group, model group 1, and model group 2. The control group was treated with a standard diet for 5 weeks. Model groups were treated with high-fat diet and CCL4 injection twice a week for 3 weeks in Group 1 and 5 weeks in Group 2, respectively. After the intervention, hepatic steatosis was observed by histological staining with hematoxylin and eosin (H&E) and Oil Red O staining. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total colesterol (TC), and triglycerides (TGs) were measured. The TG content in liver homogenates was evaluated. Expressions of HCBP6 and SREBP-1c were determined by immunofluorescence, quantitative real-time PCR, and Western blot analysis. RESULTS Hepatic steatosis was successfully induced in model groups. ALT, AST, TC, and TGs elevated in model groups compared with those in control group (P < 0.05). Hepatic steatosis induced by high-fat diet and CCL4 resulted in low expression of HCBP6 and high expression of SREBP-1c in the liver of rats (P < 0.05). CONCLUSION HCBP6 is involved in the development of high-fat diet- and CCL4-induced hepatic steatosis and related negatively with SREBP-1c.
Collapse
Affiliation(s)
- Yong-Ping Zheng
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Xian-Yang Zhong
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Yu-Shu Huang
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Can-Bin Zheng
- Department of Endocrine and Metabolic Diseases, 1st Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong province, China
| |
Collapse
|
49
|
Zhang C, Wang J, Zhang H, Liu S, Lee HJ, Jin W, Cheng J. Hepatitis C virus core protein induces hepatic steatosis via Sirt1-dependent pathway. Liver Int 2018; 38:803-812. [PMID: 28898508 DOI: 10.1111/liv.13581] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 08/23/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Hepatic steatosis is a common feature of patients with chronic hepatitis C. Previous reports have shown that the overexpression of hepatitis C virus core-encoding sequences (hepatitis C virus genotypes 3a and 1b) significantly induces intracellular triglyceride accumulation. However, the underlying mechanism has not yet been revealed. METHODS To investigate whether Sirt1 is involved in hepatitis C virus-mediated hepatic steatosis, the overexpression of hepatitis C virus core 1b protein and Sirt1 and the knockdown of Sirt1 in HepG2 cells were performed. To confirm the results of the cellular experiment liver-specific Sirt1 KO mice with lentivirus-mediated hepatitis C virus core 1b overexpression were studied. RESULTS Our results show that hepatitis C virus core 1b protein overexpression led to the accumulation of triglycerides in HepG2 cells. Notably the expression of PPARγ2 was dramatically increased at both the mRNA and protein levels by hepatitis C virus core 1b overexpression. The protein expression of Sirt1 is an upstream regulator of PPARγ2 and was also significantly increased after core 1b overexpression. In addition, the overexpression or knockdown of Sirt1 expression alone was sufficient to modulate p300-mediated PPARγ2 deacetylation. In vivo studies showed that hepatitis C virus core protein 1b-induced hepatic steatosis was attenuated in liver-specific Sirt1 KO mice by downregulation of PPARγ2 expression. CONCLUSIONS Sirt1 mediates hepatitis C virus core protein 1b-induced hepatic steatosis by regulation of PPARγ2 expression.
Collapse
Affiliation(s)
- Chuanhai Zhang
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China.,Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, China
| | - Jingjing Wang
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Hanlin Zhang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,The University of the Chinese Academy of Sciences, Beijing, China
| | - Shunai Liu
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| | - Hyuek Jong Lee
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,The University of the Chinese Academy of Sciences, Beijing, China
| | - Wanzhu Jin
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,The University of the Chinese Academy of Sciences, Beijing, China
| | - Jun Cheng
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China
| |
Collapse
|
50
|
Xu S, Zhang X, Liu P. Lipid droplet proteins and metabolic diseases. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1968-1983. [DOI: 10.1016/j.bbadis.2017.07.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 12/13/2022]
|