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Petit-Hartlein I, Vermot A, Thepaut M, Humm AS, Dupeux F, Dupuy J, Chaptal V, Marquez JA, Smith SME, Fieschi F. X-ray structure and enzymatic study of a bacterial NADPH oxidase highlight the activation mechanism of eukaryotic NOX. eLife 2024; 13:RP93759. [PMID: 38640072 PMCID: PMC11031084 DOI: 10.7554/elife.93759] [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] [Indexed: 04/21/2024] Open
Abstract
NADPH oxidases (NOX) are transmembrane proteins, widely spread in eukaryotes and prokaryotes, that produce reactive oxygen species (ROS). Eukaryotes use the ROS products for innate immune defense and signaling in critical (patho)physiological processes. Despite the recent structures of human NOX isoforms, the activation of electron transfer remains incompletely understood. SpNOX, a homolog from Streptococcus pneumoniae, can serves as a robust model for exploring electron transfers in the NOX family thanks to its constitutive activity. Crystal structures of SpNOX full-length and dehydrogenase (DH) domain constructs are revealed here. The isolated DH domain acts as a flavin reductase, and both constructs use either NADPH or NADH as substrate. Our findings suggest that hydride transfer from NAD(P)H to FAD is the rate-limiting step in electron transfer. We identify significance of F397 in nicotinamide access to flavin isoalloxazine and confirm flavin binding contributions from both DH and Transmembrane (TM) domains. Comparison with related enzymes suggests that distal access to heme may influence the final electron acceptor, while the relative position of DH and TM does not necessarily correlate with activity, contrary to previous suggestions. It rather suggests requirement of an internal rearrangement, within the DH domain, to switch from a resting to an active state. Thus, SpNOX appears to be a good model of active NOX2, which allows us to propose an explanation for NOX2's requirement for activation.
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Affiliation(s)
| | - Annelise Vermot
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie StructuraleGrenobleFrance
| | - Michel Thepaut
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie StructuraleGrenobleFrance
| | | | - Florine Dupeux
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie StructuraleGrenobleFrance
- European Molecular Biology LaboratoryGrenobleFrance
| | - Jerome Dupuy
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie StructuraleGrenobleFrance
| | | | | | - Susan ME Smith
- Department of Molecular and Cellular Biology, Kennesaw State UniversityKennesawUnited States
| | - Franck Fieschi
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie StructuraleGrenobleFrance
- Institut Universitaire de FranceParisFrance
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Romo-González M, Ijurko C, Alonso MT, Gómez de Cedrón M, Ramirez de Molina A, Soriano ME, Hernández-Hernández Á. NOX2 and NOX4 control mitochondrial function in chronic myeloid leukaemia. Free Radic Biol Med 2023; 198:92-108. [PMID: 36764627 DOI: 10.1016/j.freeradbiomed.2023.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/31/2023] [Accepted: 02/07/2023] [Indexed: 02/11/2023]
Abstract
Cancer cells are characterised by an elevated metabolic plasticity and enhanced production of reactive oxygen species (ROS), two features acknowledged as hallmarks in cancer, with a high translational potential to the therapeutic setting. These aspects, that have been traditionally studied separately, are in fact intimately intermingled. As part of their transforming activity, some oncogenes stimulate rewiring of metabolic processes, whilst simultaneously promoting increased production of intracellular ROS. In this scenario the latest discoveries suggest the relevance of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOX) to connect ROS production and metabolic control. Here we have analysed the relevance of NOX2 and NOX4 in the regulation of metabolism in chronic myeloid leukaemia (CML), a neoplasia driven by the expression of the breakpoint cluster region-Abelson fusion oncogene (BCR-ABL). Silencing of NOX2 enhances glycolysis and oxidative phosphorylation rates, together with an enhanced production of mitochondrial ROS and a decrease in mitochondrial DNA copy number, which reflects mitochondrial dysfunction. NOX4 expression was upregulated upon NOX2 silencing, and this was required to alter mitochondrial function. Our results support the relevance of NOX2 to regulate metabolism-related signalling pathways downstream of BCR-ABL. Overall we show that NOX2, through the regulation of NOX4 expression, controls metabolism and mitochondrial function in CML cells. This notion was confirmed by transcriptomic analyses, that strongly relate both NOX isoforms with metabolism regulation in CML.
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Affiliation(s)
- Marta Romo-González
- Departamento de Bioquímica y Biología Molecular, Universidad de Salamanca, Salamanca, 37007, Spain; IBSAL (Instituto de Investigación Biomédica de Salamanca), Salamanca, 37007, Spain
| | - Carla Ijurko
- Departamento de Bioquímica y Biología Molecular, Universidad de Salamanca, Salamanca, 37007, Spain; IBSAL (Instituto de Investigación Biomédica de Salamanca), Salamanca, 37007, Spain
| | - María Teresa Alonso
- Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, 47003, Spain
| | | | | | | | - Ángel Hernández-Hernández
- Departamento de Bioquímica y Biología Molecular, Universidad de Salamanca, Salamanca, 37007, Spain; IBSAL (Instituto de Investigación Biomédica de Salamanca), Salamanca, 37007, Spain.
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Abstract
NOX2 is the prototypical member of the NADPH oxidase NOX superfamily and produces superoxide (O2•-), a key reactive oxygen species (ROS) that is essential in innate and adaptive immunity. Mutations that lead to deficiency in NOX2 activity correlate with increased susceptibility to bacterial and fungal infections, resulting in chronic granulomatous disease. The core of NOX2 is formed by a heterodimeric transmembrane complex composed of NOX2 (formerly gp91) and p22, but a detailed description of its structural architecture is lacking. Here, we present the structure of the human NOX2 core complex bound to a selective anti-NOX2 antibody fragment. The core complex reveals an intricate extracellular topology of NOX2, a four-transmembrane fold of the p22 subunit, and an extensive transmembrane interface which provides insights into NOX2 assembly and activation. Functional assays uncover an inhibitory activity of the 7G5 antibody mediated by internalization-dependent and internalization-independent mechanisms. Overall, our results provide insights into the NOX2 core complex architecture, disease-causing mutations, and potential avenues for selective NOX2 pharmacological modulation.
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O'Neill S, Knaus UG. Bioluminescence-Based Complementation Assay to Correlate Conformational Changes in Membrane-Bound Complexes with Enzymatic Function. Methods Mol Biol 2022; 2525:123-137. [PMID: 35836064 DOI: 10.1007/978-1-0716-2473-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The proteomics field has undergone tremendous development with the introduction of many innovative methods for the identification and characterization of protein-protein interactions (PPIs). Sensitive and quantitative protein association-based techniques represent a versatile tool to probe the architecture of receptor complexes and receptor-ligand interactions and expand the drug discovery toolbox by facilitating high-throughput screening (HTS) approaches. These novel methodologies will be highly enabling for interrogation of structural determinants required for the activity of multimeric membrane-bound enzymes with unresolved crystal structure and for HTS assay development focused on unique characteristics of complex assembly instead of common catalytic features, thereby increasing specificity. We describe here an example of a binary luciferase reporter assay (NanoBiT®) to quantitatively assess the heterodimerization of the catalytically active NADPH oxidase 4 (NOX4) enzyme complex. The catalytic subunit NOX4 requires association with the protein p22phox for stabilization and enzymatic activity, but the precise manner by which these two membrane-bound proteins interact to facilitate hydrogen peroxide (H2O2) generation is currently unknown. The NanoBiT complementation reporter quantitatively determined the accurate, reduced, or failed complex assembly, which can then be confirmed by determining H2O2 release, protein expression, and heterodimer trafficking. Multimeric complex formation differs between NOX enzyme isoforms, facilitating isoform-specific, PPI-based drug screening in the future.
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Affiliation(s)
- Sharon O'Neill
- Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
- Legend Biotech, Dublin, Ireland
| | - Ulla G Knaus
- Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland.
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Nath N, Godat B, Flemming R, Urh M. Deciphering the Interaction between Neonatal Fc Receptor and Antibodies Using a Homogeneous Bioluminescent Immunoassay. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2021; 207:1211-1221. [PMID: 34312257 PMCID: PMC8358922 DOI: 10.4049/jimmunol.2100181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/22/2021] [Indexed: 11/19/2022]
Abstract
Long half-life of therapeutic Abs and Fc fusion proteins is crucial to their efficacy and is, in part, regulated by their interaction with neonatal Fc receptor (FcRn). However, the current methods (e.g., surface plasmon resonance and biolayer interferometry) for measurement of interaction between IgG and FcRn (IgG/FcRn) require either FcRn or IgG to be immobilized on the surface, which is known to introduce experimental artifacts and have led to conflicting data. To study IgG/FcRn interactions in solution, without a need for surface immobilization, we developed a novel (to our knowledge), solution-based homogeneous binding immunoassay based on NanoBiT luminescent protein complementation technology. We optimized the assay (NanoBiT FcRn assay) for human FcRn, mouse FcRn, rat FcRn, and cynomolgus FcRn and used them to determine the binding affinities of a panel of eight Abs. Assays could successfully capture the modulation in IgG/FcRn binding based on changes in Fc fragment of the Abs. We also looked at the individual contribution of Fc and F(ab)2 on the IgG/FcRn interaction and found that Fc is the main driver for the interaction at pH 6. Our work highlights the importance of using orthogonal methods to validate affinity data generated using biosensor platforms. Moreover, the simple add-and-read format of the NanoBiT FcRn assay is amenable for high-throughput screening during early Ab discovery phase.
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Affiliation(s)
- Nidhi Nath
- Research and Development Department, Promega Corp., Madison, WI
| | - Becky Godat
- Research and Development Department, Promega Corp., Madison, WI
| | - Rod Flemming
- Research and Development Department, Promega Corp., Madison, WI
| | - Marjeta Urh
- Research and Development Department, Promega Corp., Madison, WI
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Déri S, Borbás J, Hartai T, Hategan L, Csányi B, Visnyovszki Á, Madácsy T, Maléth J, Hegedűs Z, Nagy I, Arora R, Labro AJ, Környei L, Varró A, Sepp R, Ördög B. Impaired cytoplasmic domain interactions cause co-assembly defect and loss of function in the p.Glu293Lys KNCJ2 variant isolated from an Andersen-Tawil syndrome patient. Cardiovasc Res 2021; 117:1923-1934. [PMID: 32810216 DOI: 10.1093/cvr/cvaa249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/16/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023] Open
Abstract
AIMS Subunit interactions at the cytoplasmic domain interface (CD-I) have recently been shown to control gating in inward rectifier potassium channels. Here we report the novel KCNJ2 variant p.Glu293Lys that has been found in a patient with Andersen-Tawil syndrome type 1 (ATS1), causing amino acid substitution at the CD-I of the inward rectifier potassium channel subunit Kir2.1. Neither has the role of Glu293 in gating control been investigated nor has a pathogenic variant been described at this position. This study aimed to assess the involvement of Glu293 in CD-I subunit interactions and to establish the pathogenic role of the p.Glu293Lys variant in ATS1. METHODS AND RESULTS The p.Glu293Lys variant produced no current in homomeric form and showed dominant-negative effect over wild-type (WT) subunits. Immunocytochemical labelling showed the p.Glu293Lys subunits to distribute in the subsarcolemmal space. Salt bridge prediction indicated the presence of an intersubunit salt bridge network at the CD-I of Kir2.1, with the involvement of Glu293. Subunit interactions were studied by the NanoLuc® Binary Technology (NanoBiT) split reporter assay. Reporter constructs carrying NanoBiT tags on the intracellular termini produced no bioluminescent signal above background with the p.Glu293Lys variant in homomeric configuration and significantly reduced signals in cells co-expressing WT and p.Glu293Lys subunits simultaneously. Extracellularly presented reporter tags, however, generated comparable bioluminescent signals with heteromeric WT and p.Glu293Lys subunits and with homomeric WT channels. CONCLUSIONS Loss of function and dominant-negative effect confirm the causative role of p.Glu293Lys in ATS1. Co-assembly of Kir2.1 subunits is impaired in homomeric channels consisting of p.Glu293Lys subunits and is partially rescued in heteromeric complexes of WT and p.Glu293Lys Kir2.1 variants. These data point to an important role of Glu293 in mediating subunit assembly, as well as in gating of Kir2.1 channels.
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Affiliation(s)
- Szilvia Déri
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 12, 6720 Szeged, Hungary
| | - János Borbás
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Teodóra Hartai
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
| | - Lidia Hategan
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Beáta Csányi
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Ádám Visnyovszki
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
| | - Tamara Madácsy
- 1st Department of Internal Medicine, University of Szeged, Korányi fasor 8-10, 6720 Szeged, Hungary, Hungary
| | - József Maléth
- 1st Department of Internal Medicine, University of Szeged, Korányi fasor 8-10, 6720 Szeged, Hungary, Hungary
| | - Zoltán Hegedűs
- Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
- Department of Biochemistry and Medical Chemistry, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - István Nagy
- Institute of Biochemistry, Biological Research Centre the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
- Seqomics Biotechnology Ltd, Vállalkozók útja 7, 6782 Mórahalom, Hungary
| | - Rohit Arora
- Department of Veterinary Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
| | - Alain J Labro
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
- Department of Basic Medical Sciences, University of Ghent, C. Heymanslaan 10, 9000 Ghent, Belgium
| | - László Környei
- Gottsegen György National Institute of Cardiology, Haller u. 9, 1096 Budapest, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 12, 6720 Szeged, Hungary
- MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Dóm tér 12, 6720 Szeged, Hungary
| | - Róbert Sepp
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
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Brault J, Vigne B, Meunier M, Beaumel S, Mollin M, Park S, Stasia MJ. NOX4 is the main NADPH oxidase involved in the early stages of hematopoietic differentiation from human induced pluripotent stem cells. Free Radic Biol Med 2020; 146:107-118. [PMID: 31626946 DOI: 10.1016/j.freeradbiomed.2019.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/08/2019] [Accepted: 10/08/2019] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) produced in hematopoietic stem cells (HSCs) are involved in the balance between quiescence, self-renewal, proliferation and differentiation processes. However the role of NOX enzymes on the early stages of hematopoietic differentiation is poorly investigated. For that, we used induced pluripotent stem cells (iPSCs) derived from X-linked Chronic Granulomatous Disease (X0CGD) patients with deficiency in NOX2, and AR220CGD patients with deficiency in p22phox subunit which decreases NOX1, NOX2, NOX3 and NOX4 activities. CD34+ hematopoietic progenitors were obtained after 7, 10 and 13 days of iPS/OP9 co-culture differentiation system. Neither NOX expression nor activity was found in Wild-type (WT), X0CGD and AR220CGD iPSCs. Although NOX2 and NOX4 mRNA were found in WT, X0CGD and AR220CGD iPSC-derived CD34+ cells at day 10 and 13 of differentiation, NOX4 protein was the only NOX enzyme expressed in these cells. A NADPH oxidase activity was measured in WT and X0CGD iPSC-derived CD34+ cells but not in AR220CGD iPSC-derived CD34+ cells because of the absence of p22phox, which is essential for the NOX4 activity. The absence of NOX4 activity and the poor NOX-independent ROS production in AR220CGD iPSC-derived CD34+ cells favored the CD34+ cells production but lowered their hematopoietic potential compared to WT and X0CGD iPSC-derived CD34+ cells. In addition we found a large production of primitive AR220CGD iPSC-derived progenitors at day 7 compared to the WT and X0CGD cell types. In conclusion NOX4 is the major NOX enzyme involved in the early stages of hematopoietic differentiation from iPSCs and its activity can modulate the production, the hematopoietic potential and the phenotype of iPSC-derived CD34+.
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Affiliation(s)
- Julie Brault
- Centre Hospitalier Universitaire Grenoble Alpes, CGD Diagnosis and Research Centre (CDiReC), Grenoble, France.
| | - Bénédicte Vigne
- Centre Hospitalier Universitaire Grenoble Alpes, CGD Diagnosis and Research Centre (CDiReC), Grenoble, France.
| | - Mathieu Meunier
- Centre Hospitalier Universitaire Grenoble Alpes, University Clinic of Hematology, Grenoble, France; CNRS UMR 5309, INSERM, U1209, Université Grenoble Alpes, Institute for Advanced Bioscience, 38700, Grenoble, France.
| | - Sylvain Beaumel
- Centre Hospitalier Universitaire Grenoble Alpes, CGD Diagnosis and Research Centre (CDiReC), Grenoble, France.
| | - Michelle Mollin
- Centre Hospitalier Universitaire Grenoble Alpes, CGD Diagnosis and Research Centre (CDiReC), Grenoble, France.
| | - Sophie Park
- Centre Hospitalier Universitaire Grenoble Alpes, University Clinic of Hematology, Grenoble, France; CNRS UMR 5309, INSERM, U1209, Université Grenoble Alpes, Institute for Advanced Bioscience, 38700, Grenoble, France.
| | - Marie José Stasia
- Centre Hospitalier Universitaire Grenoble Alpes, CGD Diagnosis and Research Centre (CDiReC), Grenoble, France; Univ. Grenoble Alpes, CEA, CNRS, IBS, F-38044, Grenoble, France, Grenoble, France.
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The NADPH Oxidase and the Phagosome. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1246:153-177. [DOI: 10.1007/978-3-030-40406-2_9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Colitis susceptibility in mice with reactive oxygen species deficiency is mediated by mucus barrier and immune defense defects. Mucosal Immunol 2019; 12:1316-1326. [PMID: 31554901 DOI: 10.1038/s41385-019-0205-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/13/2019] [Accepted: 09/06/2019] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) generated by NADPH oxidases (NOX/DUOX) provide antimicrobial defense, redox signaling, and gut barrier maintenance. Inactivating NOX variants are associated with comorbid intestinal inflammation in chronic granulomatous disease (CGD; NOX2) and pediatric inflammatory bowel disease (IBD; NOX1); however Nox-deficient mice do not reflect human disease susceptibility. Here we assessed if a hypomorphic patient-relevant CGD mutation will increase the risk for intestinal inflammation in mice. Cyba (p22phox) mutant mice generated low intestinal ROS, while maintaining Nox4 function. The Cyba variant caused profound mucus layer disruption with bacterial penetration into crypts, dysbiosis, and a compromised innate immune response to invading microbes, leading to mortality. Approaches used in treatment-resistant CGD or pediatric IBD such as bone marrow transplantation or oral antibiotic treatment ameliorated or prevented disease in mice. The Cyba mutant mouse phenotype implicates loss of both mucus barrier and efficient innate immune defense in the pathogenesis of intestinal inflammation due to ROS deficiency, supporting a combined-hit model where a single disease variant compromises different cellular functions in interdependent compartments.
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Abstract
Assays based on ectopic expression of NOX NADPH oxidase subunits in heterologous mammalian cells are an important approach for investigating features of this family of enzymes. These model systems have been used to analyze the biosynthesis and functional domains of NOX enzyme components as well as their regulation and cellular activities. This chapter provides an overview of the basic principles and applications of heterologous whole cell assays in studying NOX NADPH oxidases.
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11
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Abstract
The stabilization and activation of NOX4 through its binding with p22phox are well documented; however little is known of the precise manner by which these two proteins interact. In recent years, the field of proteomics has undergone tremendous development with the introduction of many novel methods for the identification and characterization of protein-protein interactions (PPIs). To enhance our understanding of structural determinants leading to the association between NOX4 and p22phox, we developed a binary luciferase reporter assay (NanoBiT®) to quantitatively assess NOX4-p22phox heterodimerization. The complementation reporter quantitatively determines the accurate, reduced, or failed complex assembly, which can be confirmed and further interrogated by analyzing NOX4 catalytic activity (H2O2 release), protein expression, and dimer localization. This association-based PPI technique represents both a much-needed expansion of the NOX4 lead discovery tool box and a versatile method to probe the architecture of NOX and DUOX complexes in the future.
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12
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Cheng Q, Li C, Yang CF, Zhong YJ, Wu D, Shi L, Chen L, Li YW, Li L. Methyl ferulic acid attenuates liver fibrosis and hepatic stellate cell activation through the TGF-β1/Smad and NOX4/ROS pathways. Chem Biol Interact 2018; 299:131-139. [PMID: 30543783 DOI: 10.1016/j.cbi.2018.12.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/24/2018] [Accepted: 12/10/2018] [Indexed: 02/06/2023]
Abstract
Liver fibrosis is a pathological wound-healing response caused by chronic liver damage due to a virus, autoimmune disorder, or drugs. Hepatic stellate cells (HSCs) play an essential role in the pathogenesis of liver fibrosis. Methyl ferulic acid (MFA), a biologically active monomer, has a protective effect on liver injury. However, the effects and roles of MFA in liver fibrosis remain unknown. The purpose of the current study was to investigate the effect of MFA on hepatic fibrosis and the underlying mechanisms. Human hepatic stellate LX-2 cells were exposed to 5 μg/L TGF-β1 for 48 h to stimulate liver fibrosis in vitro. Using MTT, RT-PCR and Western blot analysis, we revealed that MFA significantly inhibited the proliferation of LX-2 cells as well as decreased the expressions of α-SMA and type I collagen in LX-2 cells. SD rats were fed with ethanol, and this combined with the intraperitoneal injection of CCl4 induced liver fibrosis in vivo. We found that the administration of MFA markedly decreased the levels of hyaluronic acid (HA), procollagen type III (PC-III), type IV collagen (CIV) and laminin (LN) in the serum, inhibited the expression of α-smooth muscle actin (α-SMA) as well as type I and type III collagen, and up-regulated the ratio of MMP-2/TIMP-1 in rats. The antifibrotic effects of MFA were also evaluated by H&E staining and Masson's trichrome staining. In addition, further studies suggested that this protection by MFA from liver fibrosis was possibly related to the inhibition of TGF-β1/Smad and NOX4/ROS signalling. In conclusion, our results demonstrate that MFA attenuated liver fibrosis and hepatic stellate cell activation by inhibiting the TGF-β1/Smad and NOX4/ROS signalling pathways.
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Affiliation(s)
- Qi Cheng
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Chen Li
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Cheng-Fang Yang
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Yu-Juan Zhong
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Dan Wu
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Lin Shi
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Li Chen
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China
| | - Yong-Wen Li
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China.
| | - Li Li
- College of Pharmacy, Guilin Medical University, Guilin, 541004, PR China.
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