1
|
Wuerger LTD, Kudiabor F, Alarcan J, Templin M, Poetz O, Sieg H, Braeuning A. Okadaic Acid Activates JAK/STAT Signaling to Affect Xenobiotic Metabolism in HepaRG Cells. Cells 2023; 12:770. [PMID: 36899906 PMCID: PMC10000888 DOI: 10.3390/cells12050770] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
Okadaic acid (OA) is a marine biotoxin that is produced by algae and accumulates in filter-feeding shellfish, through which it enters the human food chain, leading to diarrheic shellfish poisoning (DSP) after ingestion. Furthermore, additional effects of OA have been observed, such as cytotoxicity. Additionally, a strong downregulation of the expression of xenobiotic-metabolizing enzymes in the liver can be observed. The underlying mechanisms of this, however, remain to be examined. In this study, we investigated a possible underlying mechanism of the downregulation of cytochrome P450 (CYP) enzymes and the nuclear receptors pregnane X receptor (PXR) and retinoid-X-receptor alpha (RXRα) by OA through NF-κB and subsequent JAK/STAT activation in human HepaRG hepatocarcinoma cells. Our data suggest an activation of NF-κB signaling and subsequent expression and release of interleukins, which then activate JAK-dependent signaling and thus STAT3. Moreover, using the NF-κB inhibitors JSH-23 and Methysticin and the JAK inhibitors Decernotinib and Tofacitinib, we were also able to demonstrate a connection between OA-induced NF-κB and JAK signaling and the downregulation of CYP enzymes. Overall, we provide clear evidence that the effect of OA on the expression of CYP enzymes in HepaRG cells is regulated through NF-κB and subsequent JAK signaling.
Collapse
Affiliation(s)
- Leonie T. D. Wuerger
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Felicia Kudiabor
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Jimmy Alarcan
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Markus Templin
- NMI Natural and Medical Sciences Institute, Markwiesenstraße 55, 72770 Reutlingen, Germany
| | - Oliver Poetz
- NMI Natural and Medical Sciences Institute, Markwiesenstraße 55, 72770 Reutlingen, Germany
- SIGNATOPE GmbH, Markwiesenstraße 55, 72770 Reutlingen, Germany
| | - Holger Sieg
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Albert Braeuning
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| |
Collapse
|
2
|
Clark AR, Ohlmeyer M. Protein phosphatase 2A as a therapeutic target in inflammation and neurodegeneration. Pharmacol Ther 2019; 201:181-201. [PMID: 31158394 PMCID: PMC6700395 DOI: 10.1016/j.pharmthera.2019.05.016] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 05/29/2019] [Indexed: 12/11/2022]
Abstract
Protein phosphatase 2A (PP2A) is a highly complex heterotrimeric enzyme that catalyzes the selective removal of phosphate groups from protein serine and threonine residues. Emerging evidence suggests that it functions as a tumor suppressor by constraining phosphorylation-dependent signalling pathways that regulate cellular transformation and metastasis. Therefore, PP2A-activating drugs (PADs) are being actively sought and investigated as potential novel anti-cancer treatments. Here we explore the concept that PP2A also constrains inflammatory responses through its inhibitory effects on various signalling pathways, suggesting that PADs may be effective in the treatment of inflammation-mediated pathologies.
Collapse
Affiliation(s)
- Andrew R Clark
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
| | | |
Collapse
|
3
|
Collison AM, Li J, de Siqueira AP, Lv X, Toop HD, Morris JC, Starkey MR, Hansbro PM, Zhang J, Mattes J. TRAIL signals through the ubiquitin ligase MID1 to promote pulmonary fibrosis. BMC Pulm Med 2019; 19:31. [PMID: 30732588 PMCID: PMC6367767 DOI: 10.1186/s12890-019-0786-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 01/10/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) has previously been demonstrated to play a pro-inflammatory role in allergic airways disease and COPD through the upregulation of the E3 ubiquitin ligase MID1 and the subsequent deactivation of protein phosphatase 2A (PP2A). METHODS Biopsies were taken from eight IPF patients presenting to the Second Affiliated Hospital of Jilin University, China between January 2013 and February 2014 with control samples obtained from resected lung cancers. Serum TRAIL, MID1 protein and PP2A activity in biopsies, and patients' lung function were measured. Wild type and TRAIL deficient Tnfsf10-/- BALB/c mice were administered bleomycin to induce fibrosis and some groups were treated with the FTY720 analogue AAL(s) to activate PP2A. Mouse fibroblasts were treated with recombinant TRAIL and fibrotic responses were assessed. RESULTS TRAIL in serum and MID1 protein levels in biopsies from IPF patients were increased compared to controls. MID1 levels were inversely associated while PP2A activity levels correlated with DLco. Tnfsf10-/- and mice treated with the PP2A activator AAL(s) were largely protected against bleomycin-induced reductions in lung function and fibrotic changes. Addition of recombinant TRAIL to mouse fibroblasts in-vitro increased collagen production which was reversed by PP2A activation with AAL(s). CONCLUSION TRAIL signalling through MID1 deactivates PP2A and promotes fibrosis with corresponding lung function decline. This may provide novel therapeutic targets for IPF.
Collapse
Affiliation(s)
- Adam M. Collison
- Experimental and Translational Respiratory Medicine Group, Level 2 East, Hunter Medical Research Institute, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, NSW 2308 Australia
- Priority Research Centre GrowUpWell, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Junyao Li
- Experimental and Translational Respiratory Medicine Group, Level 2 East, Hunter Medical Research Institute, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, NSW 2308 Australia
- Priority Research Centre GrowUpWell, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
- Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Jilin University, Changchun, Jilin, 130041 People’s Republic of China
| | - Ana Pereira de Siqueira
- Experimental and Translational Respiratory Medicine Group, Level 2 East, Hunter Medical Research Institute, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, NSW 2308 Australia
- Priority Research Centre GrowUpWell, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Xuejiao Lv
- Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Jilin University, Changchun, Jilin, 130041 People’s Republic of China
| | - Hamish D. Toop
- School of Chemistry, University of New South Wales, Sydney, New South Wales Australia
| | - Jonathan C. Morris
- School of Chemistry, University of New South Wales, Sydney, New South Wales Australia
| | - Malcolm R. Starkey
- Priority Research Centre GrowUpWell, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
- Priority Research Centre for Healthy Lungs, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Philip M. Hansbro
- Priority Research Centre for Healthy Lungs, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Jie Zhang
- Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Jilin University, Changchun, Jilin, 130041 People’s Republic of China
| | - Joerg Mattes
- Experimental and Translational Respiratory Medicine Group, Level 2 East, Hunter Medical Research Institute, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, NSW 2308 Australia
- Priority Research Centre GrowUpWell, The University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
- Paediatric Respiratory & Sleep Medicine Department, Newcastle Children’s Hospital, Kaleidoscope, Newcastle, Australia
| |
Collapse
|
4
|
Sheu JR, Chen ZC, Hsu MJ, Wang SH, Jung KW, Wu WF, Pan SH, Teng RD, Yang CH, Hsieh CY. CME-1, a novel polysaccharide, suppresses iNOS expression in lipopolysaccharide-stimulated macrophages through ceramide-initiated protein phosphatase 2A activation. J Cell Mol Med 2017; 22:999-1013. [PMID: 29214724 PMCID: PMC5783865 DOI: 10.1111/jcmm.13424] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/20/2017] [Indexed: 12/22/2022] Open
Abstract
CME-1, a novel water-soluble polysaccharide purified from Ophiocordyceps sinensis mycelia, has anti-oxidative, antithrombotic and antitumour properties. In this study, other major attributes of CME-1, namely anti-inflammatory and immunomodulatory properties, were investigated. Treating lipopolysaccharide (LPS)-stimulated RAW 264.7 cells with CME-1 concentration-dependently suppressed nitric oxide formation and inducible nitric oxide synthase (iNOS) expression. In the CME-1-treated RAW 264.7 cells, LPS-induced IκBα degradation and the phosphorylation of p65, Akt and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38, were reduced. Treatment with a protein phosphatase 2A (PP2A)-specific inhibitor, significantly reversed the CME-1-suppressed iNOS expression; IκBα degradation; and p65, Akt and MAPK phosphorylation. PP2A activity up-regulation and PP2A demethylation reduction were also observed in the cells. Moreover, CME-1-induced PP2A activation and its subsequent suppression of LPS-activated RAW 264.7 cells were diminished by the inhibition of ceramide signals. LPS-induced reactive oxygen species (ROS) and hydroxyl radical formation were eliminated by treating RAW 264.7 cells with CME-1. Furthermore, the role of ceramide signalling pathway and anti-oxidative property were also demonstrated in CME-1-mediated inhibition of LPS-activated primary peritoneal macrophages. In conclusion, CME-1 suppressed iNOS expression by up-regulating ceramide-induced PP2A activation and reducing ROS production in LPS-stimulated macrophages. CME-1 is a potential therapeutic agent for treating inflammatory diseases.
Collapse
Affiliation(s)
- Joen-Rong Sheu
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan.,Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Zhih-Cherng Chen
- Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Cardiology, Chi-Mei Medical Center, Tainan City, Taiwan.,Department of Pharmacy, Chia Nan University of Pharmacy & Science, Tainan City, Taiwan
| | - Ming-Jen Hsu
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Shwu-Huey Wang
- Core Facility Center, Office of Research and Development, Taipei Medical University, Taipei, Taiwan
| | - Kuo-Wei Jung
- Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Wei-Fan Wu
- Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Szu-Han Pan
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ruei-Dun Teng
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chih-Hao Yang
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Cheng-Ying Hsieh
- Department of Pharmacology, School of Medicine, Taipei Medical University, Taipei, Taiwan
| |
Collapse
|
5
|
Sokulsky LA, Collison AM, Nightingale S, Fevre AL, Percival E, Starkey MR, Hansbro PM, Foster PS, Mattes J. TRAIL deficiency and PP2A activation with salmeterol ameliorates egg allergen-driven eosinophilic esophagitis. Am J Physiol Gastrointest Liver Physiol 2016; 311:G998-G1008. [PMID: 27742702 DOI: 10.1152/ajpgi.00151.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 10/05/2016] [Indexed: 01/31/2023]
Abstract
Food antigens are common inflammatory triggers in pediatric eosinophilic esophagitis (EoE). TNF-related apoptosis-inducing ligand (TRAIL) promotes eosinophilic inflammation through the upregulation of the E3 ubiquitin ligase Midline (MID)-1 and subsequent downregulation of protein phosphatase 2A (PP2A), but the role of this pathway in EoE that is experimentally induced by repeated food antigen challenges has not been investigated. Esophageal mucosal biopsies were collected from children with EoE and controls and assessed for TRAIL and MID-1 protein and mRNA transcript levels. Wild-type and TRAIL-deficient (Tnfsf10-/-) mice were administered subcutaneous ovalbumin (OVA) followed by oral OVA challenges. In separate experiments, OVA-challenged mice were intraperitoneally administered salmeterol or dexamethasone. Esophageal biopsies from children with EoE revealed increased levels of TRAIL and MID-1 and reduced PP2A activation compared with controls. Tnfsf10-/- mice were largely protected from esophageal fibrosis, eosinophilic inflammation, and the upregulation of TSLP, IL-5, IL-13, and CCL11 when compared with wild-type mice. Salmeterol administration to wild-type mice with experimental EoE restored PP2A activity and also prevented esophageal eosinophilia, inflammatory cytokine expression, and remodeling, which was comparable to the treatment effect of dexamethasone. TRAIL and PP2A regulate inflammation and fibrosis in experimental EoE, which can be therapeutically modulated by salmeterol.
Collapse
Affiliation(s)
- Leon A Sokulsky
- The Priority Research Centre GrowUpWell, Newcastle, Australia
| | - Adam M Collison
- The Priority Research Centre GrowUpWell, Newcastle, Australia;
| | | | - Anna Le Fevre
- The Priority Research Centre GrowUpWell, Newcastle, Australia
| | - Elizabeth Percival
- The Priority Research Centre GrowUpWell, Newcastle, Australia
- Department of Gastroenterology and the Department of Respiratory and Sleep Medicine, John Hunter Children's Hospital, Newcastle, Newcastle, Australia
| | | | - Philip M Hansbro
- Priority Research Centre for Lung Health, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; and
| | - Paul S Foster
- Priority Research Centre for Lung Health, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; and
| | - Joerg Mattes
- The Priority Research Centre GrowUpWell, Newcastle, Australia
- Department of Gastroenterology and the Department of Respiratory and Sleep Medicine, John Hunter Children's Hospital, Newcastle, Newcastle, Australia
| |
Collapse
|
6
|
Rahman MM, Prünte L, Lebender LF, Patel BS, Gelissen I, Hansbro PM, Morris JC, Clark AR, Verrills NM, Ammit AJ. The phosphorylated form of FTY720 activates PP2A, represses inflammation and is devoid of S1P agonism in A549 lung epithelial cells. Sci Rep 2016; 6:37297. [PMID: 27849062 PMCID: PMC5110966 DOI: 10.1038/srep37297] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 10/27/2016] [Indexed: 12/21/2022] Open
Abstract
Protein phosphatase 2A (PP2A) activity can be enhanced pharmacologically by PP2A-activating drugs (PADs). The sphingosine analog FTY720 is the best known PAD and we have shown that FTY720 represses production of pro-inflammatory cytokines responsible for respiratory disease pathogenesis. Whether its phosphorylated form, FTY720-P, also enhances PP2A activity independently of the sphingosine 1-phosphate (S1P) pathway was unknown. Herein, we show that FTY720-P enhances TNF-induced PP2A phosphatase activity and significantly represses TNF-induced interleukin 6 (IL-6) and IL-8 mRNA expression and protein secretion from A549 lung epithelial cells. Comparing FTY720 and FTY720-P with S1P, we show that unlike S1P, the sphingosine analogs do not induce cytokine production on their own. In fact, FTY720 and FTY720-P significantly repress S1P-induced IL-6 and IL-8 production. We then examined their impact on expression of cyclooxygenase 2 (COX-2) and resultant prostaglandin E2 (PGE2) production. S1P did not increase production of this pro-inflammatory enzyme because COX-2 mRNA gene expression is NF-κB-dependent, and unlike TNF, S1P did not activate NF-κB. However, TNF-induced COX-2 mRNA expression and PGE2 secretion is repressed by FTY720 and FTY720-P. Hence, FTY720-P enhances PP2A activity and that PADs can repress production of pro-inflammatory cytokines and enzymes in A549 lung epithelial cells in a manner devoid of S1P agonism.
Collapse
Affiliation(s)
| | - Laura Prünte
- Faculty of Pharmacy, University of Sydney, NSW, 2006, Australia
| | | | | | - Ingrid Gelissen
- Faculty of Pharmacy, University of Sydney, NSW, 2006, Australia
| | - Philip M. Hansbro
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and the University of Newcastle, NSW, 2308, Australia
| | | | - Andrew R. Clark
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston B15 2TT, United Kingdom
| | - Nicole M. Verrills
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, NSW, 2308, Australia
| | - Alaina J. Ammit
- Woolcock Emphysema Centre, Woolcock Institute of Medical Research, University of Sydney, NSW, Australia
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW, Australia
| |
Collapse
|
7
|
McDermott JE, Mitchell HD, Gralinski LE, Eisfeld AJ, Josset L, Bankhead A, Neumann G, Tilton SC, Schäfer A, Li C, Fan S, McWeeney S, Baric RS, Katze MG, Waters KM. The effect of inhibition of PP1 and TNFα signaling on pathogenesis of SARS coronavirus. BMC SYSTEMS BIOLOGY 2016; 10:93. [PMID: 27663205 PMCID: PMC5035469 DOI: 10.1186/s12918-016-0336-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 09/08/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND The complex interplay between viral replication and host immune response during infection remains poorly understood. While many viruses are known to employ anti-immune strategies to facilitate their replication, highly pathogenic virus infections can also cause an excessive immune response that exacerbates, rather than reduces pathogenicity. To investigate this dichotomy in severe acute respiratory syndrome coronavirus (SARS-CoV), we developed a transcriptional network model of SARS-CoV infection in mice and used the model to prioritize candidate regulatory targets for further investigation. RESULTS We validated our predictions in 18 different knockout (KO) mouse strains, showing that network topology provides significant predictive power to identify genes that are important for viral infection. We identified a novel player in the immune response to virus infection, Kepi, an inhibitory subunit of the protein phosphatase 1 (PP1) complex, which protects against SARS-CoV pathogenesis. We also found that receptors for the proinflammatory cytokine tumor necrosis factor alpha (TNFα) promote pathogenesis, presumably through excessive inflammation. CONCLUSIONS The current study provides validation of network modeling approaches for identifying important players in virus infection pathogenesis, and a step forward in understanding the host response to an important infectious disease. The results presented here suggest the role of Kepi in the host response to SARS-CoV, as well as inflammatory activity driving pathogenesis through TNFα signaling in SARS-CoV infections. Though we have reported the utility of this approach in bacterial and cell culture studies previously, this is the first comprehensive study to confirm that network topology can be used to predict phenotypes in mice with experimental validation.
Collapse
Affiliation(s)
- Jason E. McDermott
- Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99354 USA
| | - Hugh D. Mitchell
- Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99354 USA
| | - Lisa E. Gralinski
- Department of Epidemiology, University of North Carolina Chapel Hill, Chapel Hill, NC 27599 USA
| | - Amie J. Eisfeld
- Department of Pathobiological Sciences, School of Veterinary Medicine, Influenza Research Institute, University of Wisconsin-Madison, Madison, WI 53715 USA
| | - Laurence Josset
- Department of Microbiology, University of Washington, Seattle, WA 98195 USA
| | - Armand Bankhead
- Division of Biostatistics, Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR 97239 USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, OR 97239 USA
| | - Gabriele Neumann
- Department of Pathobiological Sciences, School of Veterinary Medicine, Influenza Research Institute, University of Wisconsin-Madison, Madison, WI 53715 USA
| | - Susan C. Tilton
- Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99354 USA
| | - Alexandra Schäfer
- Department of Epidemiology, University of North Carolina Chapel Hill, Chapel Hill, NC 27599 USA
| | - Chengjun Li
- Department of Pathobiological Sciences, School of Veterinary Medicine, Influenza Research Institute, University of Wisconsin-Madison, Madison, WI 53715 USA
| | - Shufang Fan
- Department of Pathobiological Sciences, School of Veterinary Medicine, Influenza Research Institute, University of Wisconsin-Madison, Madison, WI 53715 USA
| | - Shannon McWeeney
- Division of Biostatistics, Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR 97239 USA
| | - Ralph S. Baric
- Department of Epidemiology, University of North Carolina Chapel Hill, Chapel Hill, NC 27599 USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 USA
| | - Michael G. Katze
- Department of Microbiology, University of Washington, Seattle, WA 98195 USA
| | - Katrina M. Waters
- Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99354 USA
| |
Collapse
|
8
|
Rahman MM, Prabhala P, Rumzhum NN, Patel BS, Wickop T, Hansbro PM, Verrills NM, Ammit AJ. TLR2 ligation induces corticosteroid insensitivity in A549 lung epithelial cells: Anti-inflammatory impact of PP2A activators. Int J Biochem Cell Biol 2016; 78:279-287. [PMID: 27477309 DOI: 10.1016/j.biocel.2016.07.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 07/21/2016] [Accepted: 07/27/2016] [Indexed: 01/18/2023]
Abstract
Corticosteroids are effective anti-inflammatory therapies widely utilized in chronic respiratory diseases. But these medicines can lose their efficacy during respiratory infection resulting in disease exacerbation. Further in vitro research is required to understand how infection worsens lung function control in order to advance therapeutic options to treat infectious exacerbation in the future. In this study, we utilize a cellular model of bacterial exacerbation where we pretreat A549 lung epithelial cells with the synthetic bacterial lipoprotein Pam3CSK4 (a TLR2 ligand) to mimic bacterial infection and tumor necrosis factor α (TNFα) to simulate inflammation. Under these conditions, Pam3CSK4 induces corticosteroid insensitivity; demonstrated by substantially reduced ability of the corticosteroid dexamethasone to repress TNFα-induced interleukin 6 secretion. We then explored the molecular mechanism responsible and found that corticosteroid insensitivity induced by bacterial mimics was not due to altered translocation of the glucocorticoid receptor into the nucleus, nor an impact on the NF-κB pathway. Moreover, Pam3CSK4 did not affect corticosteroid-induced upregulation of anti-inflammatory MAPK deactivating phosphatase-MKP-1. However, Pam3CSK4 can induce oxidative stress and we show that a proportion of the MKP-1 produced in response to corticosteroid in the context of TLR2 ligation was rendered inactive by oxidation. Thus to combat inflammation in the context of bacterial exacerbation we sought to discover effective strategies that bypassed this road-block. We show for the first time that known (FTY720) and novel (theophylline) activators of the phosphatase PP2A can serve as non-steroidal anti-inflammatory alternatives and/or corticosteroid-sparing approaches in respiratory inflammation where corticosteroid insensitivity exists.
Collapse
Affiliation(s)
| | - Pavan Prabhala
- Faculty of Pharmacy, University of Sydney, NSW, Australia
| | | | | | - Thomas Wickop
- Faculty of Pharmacy, University of Sydney, NSW, Australia
| | - Philip M Hansbro
- Priority Research Centre for Respiratory Diseases, Hunter Medical Research Institute and The University of Newcastle, Newcastle, Australia
| | - Nicole M Verrills
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, NSW, Australia
| | - Alaina J Ammit
- Woolcock Emphysema Centre, Woolcock Institute of Medical Research, University of Sydney, NSW, Australia; School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW, Australia.
| |
Collapse
|
9
|
Crotty Alexander LE, Shin S, Hwang JH. Inflammatory Diseases of the Lung Induced by Conventional Cigarette Smoke: A Review. Chest 2016; 148:1307-1322. [PMID: 26135024 DOI: 10.1378/chest.15-0409] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Smoking-induced lung diseases were extremely rare prior to the 20th century. With commercialization and introduction of machine-made cigarettes, worldwide use skyrocketed and several new pulmonary diseases have been recognized. The majority of pulmonary diseases caused by cigarette smoke (CS) are inflammatory in origin. Airway epithelial cells and alveolar macrophages have altered inflammatory signaling in response to CS, which leads to recruitment of lymphocytes, eosinophils, neutrophils, and mast cells to the lungs-depending on the signaling pathway (nuclear factor-κB, adenosine monophosphate-activated protein kinase, c-Jun N-terminal kinase, p38, and signal transducer and activator of transcription 3) activated. Multiple proteins are upregulated and secreted in response to CS exposure, and many of these have immunomodulatory activities that contribute to disease pathogenesis. In particular, metalloproteases 9 and 12, surfactant protein D, antimicrobial peptides (LL-37 and human β defensin 2), and IL-1, IL-6, IL-8, and IL-17 have been found in higher quantities in the lungs of smokers with ongoing inflammation. However, many underlying mechanisms of smoking-induced inflammatory diseases are not yet known. We review here the known cellular and molecular mechanisms of CS-induced diseases, including COPD, respiratory bronchiolitis-interstitial lung disease, desquamative interstitial pneumonia, acute eosinophilic pneumonia, chronic rhinosinusitis, pulmonary Langerhans cell histiocytosis, and chronic bacterial infections. We also discuss inflammation induced by secondhand and thirdhand smoke exposure and the pulmonary diseases that result. New targeted antiinflammatory therapeutic options are currently under investigation and hopefully will yield promising results for the treatment of these highly prevalent smoking-induced diseases.
Collapse
Affiliation(s)
- Laura E Crotty Alexander
- Veterans Affairs San Diego Healthcare System; and University of California, San Diego, La Jolla, CA..
| | - Stephanie Shin
- Veterans Affairs San Diego Healthcare System; and University of California, San Diego, La Jolla, CA
| | - John H Hwang
- Veterans Affairs San Diego Healthcare System; and University of California, San Diego, La Jolla, CA
| |
Collapse
|
10
|
Rahman MM, Rumzhum NN, Hansbro PM, Morris JC, Clark AR, Verrills NM, Ammit AJ. Activating protein phosphatase 2A (PP2A) enhances tristetraprolin (TTP) anti-inflammatory function in A549 lung epithelial cells. Cell Signal 2016; 28:325-34. [PMID: 26820662 DOI: 10.1016/j.cellsig.2016.01.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/21/2016] [Accepted: 01/23/2016] [Indexed: 12/13/2022]
Abstract
Chronic respiratory diseases are driven by inflammation, but some clinical conditions (severe asthma, COPD) are refractory to conventional anti-inflammatory therapies. Thus, novel anti-inflammatory strategies are necessary. The mRNA destabilizing protein, tristetraprolin (TTP), is an anti-inflammatory molecule that functions to induce mRNA decay of cytokines that drive pathogenesis of respiratory disorders. TTP is regulated by phosphorylation and protein phosphatase 2A (PP2A) is responsible for dephosphorylating (and hence activating) TTP, amongst other targets. PP2A is activated by small molecules, FTY720 and AAL(S), and in this study we examine whether these compounds repress cytokine production in a cellular model of airway inflammation using A549 lung epithelial cells stimulated with tumor necrosis factor α (TNFα) in vitro. PP2A activators significantly increase TNFα-induced PP2A activity and inhibit mRNA expression and protein secretion of interleukin 8 (IL-8) and IL-6; two key pro-inflammatory cytokines implicated in respiratory disease and TTP targets. The effect of PP2A activators is not via an increase in TNFα-induced TTP mRNA expression; instead we demonstrate a link between PP2A activation and TTP anti-inflammatory function by showing that specific knockdown of TTP with siRNA reversed the repression of TNFα-induced IL-8 and IL-6 mRNA expression and protein secretion by FTY720. Therefore we propose that PP2A activators affect the dynamic equilibrium regulating TTP; shifting the equilibrium from phosphorylated (inactive) towards unphosphorylated (active) but unstable TTP. PP2A activators boost the anti-inflammatory function of TTP and have implications for future pharmacotherapeutic strategies to combat inflammation in respiratory disease.
Collapse
Affiliation(s)
| | | | - Philip M Hansbro
- Priority Research Centre for Respiratory Diseases, Hunter Medical Research Institute, University of Newcastle, NSW 2308, Australia
| | | | - Andrew R Clark
- Centre for Translational Inflammation Research, School of Immunity and Infection, University of Birmingham, Edgbaston B15 2TT, United Kingdom
| | - Nicole M Verrills
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, NSW 2308, Australia
| | - Alaina J Ammit
- Faculty of Pharmacy, University of Sydney, NSW 2006, Australia.
| |
Collapse
|
11
|
Hara-Chikuma M, Satooka H, Watanabe S, Honda T, Miyachi Y, Watanabe T, Verkman AS. Aquaporin-3-mediated hydrogen peroxide transport is required for NF-κB signalling in keratinocytes and development of psoriasis. Nat Commun 2015; 6:7454. [PMID: 26100668 DOI: 10.1038/ncomms8454] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 05/10/2015] [Indexed: 12/23/2022] Open
Abstract
Aquaporin 3 (AQP3), a water/glycerol channel protein, has been found to transport hydrogen peroxide (H2O2). Here, we show that H2O2, imported via AQP3, is involved in nuclear factor-κB (NF-κB) signalling in keratinocytes and in the pathogenesis of psoriasis. IL-23-mediated induction of psoriasis is reduced in AQP3 knockout mice (AQP3(-/-)), and is accompanied by impaired NF-κB activation and intracellular H2O2 accumulation. In primary keratinocyte cultures, cellular import of H2O2 produced by membrane NADPH oxidase 2 (Nox2) in response to TNF-α is facilitated by AQP3 and required for NF-κB activation by regulation of protein phosphatase 2A. As AQP3 associates with Nox2, we propose that this interplay constitutes H2O2-mediated signalling in response to TNF-α stimulation. Collectively, these data indicate that AQP3-facilitated H2O2 transport is required for NF-κB activation in keratinocytes in the development of psoriasis.
Collapse
Affiliation(s)
- Mariko Hara-Chikuma
- Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Hiroki Satooka
- Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Sachiko Watanabe
- Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Tetsuya Honda
- 1] Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan [2] Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Yoshiki Miyachi
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Takeshi Watanabe
- Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - A S Verkman
- Department of Medicine and Physiology, University of California, San Francisco, California 94143, USA
| |
Collapse
|
12
|
Geraghty P, Eden E, Pillai M, Campos M, McElvaney NG, Foronjy RF. α1-Antitrypsin activates protein phosphatase 2A to counter lung inflammatory responses. Am J Respir Crit Care Med 2014; 190:1229-42. [PMID: 25341065 PMCID: PMC4315812 DOI: 10.1164/rccm.201405-0872oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 09/25/2014] [Indexed: 12/26/2022] Open
Abstract
RATIONALE α1-Antitrypsin (A1AT) was identified as a plasma protease inhibitor; however, it is now recognized as a multifunctional protein that modulates immunity, inflammation, proteostasis, apoptosis, and cellular senescence. Like A1AT, protein phosphatase 2A (PP2A), a major serine-threonine phosphatase, regulates similar biologic processes and plays a key role in chronic obstructive pulmonary disease. OBJECTIVES Given their common effects, this study investigated whether A1AT acts via PP2A to alter tumor necrosis factor (TNF) signaling, inflammation, and proteolytic responses in this disease. METHODS PP2A activity was measured in peripheral blood neutrophils from A1AT-deficient (PiZZ) and healthy (PiMM) individuals and in alveolar macrophages from normal (60 mg/kg) and high-dose (120 mg/kg) A1AT-treated PiZZ subjects. PP2A activation was assessed in human neutrophils, airway epithelial cells, and peripheral blood monocytes treated with plasma purified A1AT protein. Similarly, lung PP2A activity was measured in mice administered intranasal A1AT. PP2A was silenced in lung epithelial cells treated with A1AT and matrix metalloproteinase and cytokine production was then measured following TNF-α stimulation. MEASUREMENTS AND MAIN RESULTS PP2A was significantly lower in neutrophils isolated from PiZZ compared with PiMM subjects. A1AT protein activated PP2A in human alveolar macrophages, monocytes, neutrophils, airway epithelial cells, and in mouse lungs. This activation required functionally active A1AT protein and protein tyrosine phosphatase 1B expression. A1AT treatment acted via PP2A to prevent p38 and IκBα phosphorylation and matrix metalloproteinase and cytokine induction in TNF-α-stimulated epithelial cells. CONCLUSIONS Together, these data indicate that A1AT modulates PP2A to counter inflammatory and proteolytic responses induced by TNF signaling in the lung.
Collapse
Affiliation(s)
- Patrick Geraghty
- 1 Division of Pulmonary and Critical Care Medicine, Mount Sinai Roosevelt Hospital, New York, New York
| | | | | | | | | | | |
Collapse
|
13
|
Loss of calreticulin function decreases NFκB activity by stabilizing IκB protein. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2385-93. [PMID: 24998604 DOI: 10.1016/j.bbamcr.2014.06.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 05/27/2014] [Accepted: 06/24/2014] [Indexed: 12/21/2022]
Abstract
Transcription factor NFκB is activated by several processes including inflammation, endoplasmic-reticulum (ER) stress, increase in Akt signaling and enhanced proteasomal degradation. Calreticulin (CRT) is an ER Ca(2+)-binding chaperone that regulates many cellular processes. Gene-targeted deletion of CRT has been shown to induce ER stress that is accompanied with a significant increase in the proteasome activity. Loss of CRT function increases the resistance of CRT-deficient (crt-/-) cells to UV- and drug-induced apoptosis. Based on these reports we hypothesized that loss of CRT will activate NFκB signaling thus contributing to enhanced resistance to apoptosis. In contrast to our hypothesis, we observed a significant decrease in the basal transcriptional activity of NFκB in CRT-deficient cells. Treatment with lipopolysaccharide failed to increase the transcriptional activity of NFκB in the crt-/- cells to the same level as in the wt cells. Our data illustrate that the mechanism of decreased NFκB activity in CRT-deficient cells is mediated by a significant increase in IκB protein expression. Furthermore, we showed a significant increase in protein phosphatase 2A activity inhibition which resulted in decreased IκBα protein level in CRT-deficient cells. Based on our data we concluded that loss of CRT increases the stability of IκB protein thus reducing NFκB activity.
Collapse
|
14
|
Breuer R, Becker MS, Brechmann M, Mock T, Arnold R, Krammer PH. The protein phosphatase 2A regulatory subunit B56γ mediates suppression of T cell receptor (TCR)-induced nuclear factor-κB (NF-κB) activity. J Biol Chem 2014; 289:14996-5004. [PMID: 24719332 DOI: 10.1074/jbc.m113.533547] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
NF-κB is an important transcription factor in the immune system, and aberrant NF-κB activity contributes to malignant diseases and autoimmunity. In T cells, NF-κB is activated upon TCR stimulation, and signal transduction to NF-κB activation is triggered by a cascade of phosphorylation events. However, fine-tuning and termination of TCR signaling are only partially understood. Phosphatases oppose the role of kinases by removing phosphate moieties. The catalytic activity of the protein phosphatase PP2A has been implicated in the regulation of NF-κB. PP2A acts in trimeric complexes in which the catalytic subunit is promiscuous and the regulatory subunit confers substrate specificity. To understand and eventually target NF-κB-specific PP2A functions it is essential to define the regulatory PP2A subunit involved. So far, the regulatory PP2A subunit that mediates NF-κB suppression in T cells remained undefined. By performing a siRNA screen in Jurkat T cells harboring a NF-κB-responsive luciferase reporter, we identified the PP2A regulatory subunit B56γ as negative regulator of NF-κB in TCR signaling. B56γ was strongly up-regulated upon primary human T cell activation, and B56γ silencing induced increased IκB kinase (IKK) and IκBα phosphorylation upon TCR stimulation. B56γ silencing enhanced NF-κB activity, resulting in increased NF-κB target gene expression including the T cell cytokine IL-2. In addition, T cell proliferation was increased upon B56γ silencing. These data help to understand the physiology of PP2A function in T cells and the pathophysiology of diseases involving PP2A and NF-κB.
Collapse
Affiliation(s)
- Rebecca Breuer
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| | - Michael S Becker
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| | - Markus Brechmann
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| | - Thomas Mock
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| | - Rüdiger Arnold
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| | - Peter H Krammer
- From the Division of Immunogenetics, German Cancer Research Center (Deutsches Krebsforschungszentrum), 69120 Heidelberg, Germany
| |
Collapse
|
15
|
Hatchwell L, Girkin J, Dun MD, Morten M, Verrills N, Toop HD, Morris JC, Johnston SL, Foster PS, Collison A, Mattes J. Salmeterol attenuates chemotactic responses in rhinovirus-induced exacerbation of allergic airways disease by modulating protein phosphatase 2A. J Allergy Clin Immunol 2014; 133:1720-7. [PMID: 24388637 DOI: 10.1016/j.jaci.2013.11.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 10/29/2013] [Accepted: 11/13/2013] [Indexed: 01/17/2023]
Abstract
BACKGROUND β-Agonists are used for relief and control of asthma symptoms by reversing bronchoconstriction. They might also have anti-inflammatory properties, but the underpinning mechanisms remain poorly understood. Recently, a direct interaction between formoterol and protein phosphatase 2A (PP2A) has been described in vitro. OBJECTIVE We sought to elucidate the molecular mechanisms by which β-agonists exert anti-inflammatory effects in allergen-driven and rhinovirus 1B-exacerbated allergic airways disease (AAD). METHODS Mice were sensitized and then challenged with house dust mite to induce AAD while receiving treatment with salmeterol, formoterol, or salbutamol. Mice were also infected with rhinovirus 1B to exacerbate lung inflammation and therapeutically administered salmeterol, dexamethasone, or the PP2A-activating drug (S)-2-amino-4-(4-[heptyloxy]phenyl)-2-methylbutan-1-ol (AAL[S]). RESULTS Systemic or intranasal administration of salmeterol protected against the development of allergen- and rhinovirus-induced airway hyperreactivity and decreased eosinophil recruitment to the lungs as effectively as dexamethasone. Formoterol and salbutamol also showed anti-inflammatory properties. Salmeterol, but not dexamethasone, increased PP2A activity, which reduced CCL11, CCL20, and CXCL2 expression and reduced levels of phosphorylated extracellular signal-regulated kinase 1 and active nuclear factor κB subunits in the lungs. The anti-inflammatory effect of salmeterol was blocked by targeting the catalytic subunit of PP2A with small RNA interference. Conversely, increasing PP2A activity with AAL(S) abolished rhinovirus-induced airway hyperreactivity, eosinophil influx, and CCL11, CCL20, and CXCL2 expression. Salmeterol also directly activated immunoprecipitated PP2A in vitro isolated from human airway epithelial cells. CONCLUSIONS Salmeterol exerts anti-inflammatory effects by increasing PP2A activity in AAD and rhinovirus-induced lung inflammation, which might potentially account for some of its clinical benefits.
Collapse
Affiliation(s)
- Luke Hatchwell
- Experimental & Translational Respiratory Medicine Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Jason Girkin
- Experimental & Translational Respiratory Medicine Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Matthew D Dun
- Medical Biochemistry Department, School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia; Hunter Medical Research Institute, Cancer Research Program and Hunter Cancer Research Alliance, Newcastle, Australia
| | - Matthew Morten
- Experimental & Translational Respiratory Medicine Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Nicole Verrills
- Medical Biochemistry Department, School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia; Hunter Medical Research Institute, Cancer Research Program and Hunter Cancer Research Alliance, Newcastle, Australia
| | - Hamish D Toop
- School of Chemistry, University of New South Wales, Sydney, Australia
| | - Jonathan C Morris
- School of Chemistry, University of New South Wales, Sydney, Australia
| | - Sebastian L Johnston
- Airway Disease Infection Section, National Heart and Lung Institute, Medical Research Council & Asthma UK Centre in Allergic Mechanisms of Asthma, Imperial College London, London, United Kingdom
| | - Paul S Foster
- Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Adam Collison
- Experimental & Translational Respiratory Medicine Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia
| | - Joerg Mattes
- Experimental & Translational Respiratory Medicine Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Priority Research Centre for Asthma and Respiratory Diseases, University of Newcastle and Hunter Medical Research Institute, Newcastle, Australia; Paediatric Respiratory and Sleep Medicine Unit, Newcastle Children's Hospital, Kaleidoscope, Newcastle, Australia.
| |
Collapse
|
16
|
Haneji T, Hirashima K, Teramachi J, Morimoto H. Okadaic acid activates the PKR pathway and induces apoptosis through PKR stimulation in MG63 osteoblast-like cells. Int J Oncol 2013; 42:1904-10. [PMID: 23591640 PMCID: PMC3699595 DOI: 10.3892/ijo.2013.1911] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 03/27/2013] [Indexed: 12/04/2022] Open
Abstract
Double-stranded RNA-dependent protein kinase (PKR) is one of the players in the cellular antiviral responses and is involved in transcriptional stimulation through activation of NF-κB. Treatment of the human osteosarcoma cell line MG63 with the protein phosphatase inhibitor okadaic acid stimulated the expression and phosphorylation of IκBα, as judged from the results of real-time PCR and western blot analysis. We investigated the functional relationship between PKR and signal transduction of NF-κB by establishing PKR-K/R cells that produced a catalytically inactive mutant of PKR. Phosphorylation of eIF-2α, a substrate of PKR, was not stimulated by okadaic acid in the PKR-K/R cells, whereas okadaic acid induced phosphorylation of eIF-2α in MG63 cells. Phosphorylation of NF-κB in MG63 cells was stimulated by okadaic acid; however, okadaic acid did not induce phosphorylation of NF-κB in the PKR-K/R cells. Finally, okadaic acid-induced apoptosis was inhibited in the PKR-K/R cells. Our results suggest that okadaic acid-induced phosphorylation of IκBα was mediated by PKR kinase activity, thus, indicating the involvement of this kinase in the control mechanism governing the activation of NF-κB and induction of apoptosis.
Collapse
Affiliation(s)
- Tatsuji Haneji
- Department of Histology and Oral Histology, Institute of Health Biosciences, The University of Tokushima Graduate School, Kuramoto, Tokushima 770-8504, Japan.
| | | | | | | |
Collapse
|
17
|
Collison A, Hatchwell L, Verrills N, Wark PAB, de Siqueira AP, Tooze M, Carpenter H, Don AS, Morris JC, Zimmermann N, Bartlett NW, Rothenberg ME, Johnston SL, Foster PS, Mattes J. The E3 ubiquitin ligase midline 1 promotes allergen and rhinovirus-induced asthma by inhibiting protein phosphatase 2A activity. Nat Med 2013; 19:232-7. [PMID: 23334847 DOI: 10.1038/nm.3049] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 11/29/2012] [Indexed: 12/30/2022]
Abstract
Allergic airway inflammation is associated with activation of innate immune pathways by allergens. Acute exacerbations of asthma are commonly associated with rhinovirus infection. Here we show that, after exposure to house dust mite (HDM) or rhinovirus infection, the E3 ubiquitin ligase midline 1 (MID1) is upregulated in mouse bronchial epithelium. HDM regulates MID1 expression in a Toll-like receptor 4 (TLR4)- and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-dependent manner. MID1 decreases protein phosphatase 2A (PP2A) activity through association with its catalytic subunit PP2Ac. siRNA-mediated knockdown of MID1 or pharmacological activation of PP2A using a nonphosphorylatable FTY720 analog in mice exposed to HDM reduces airway hyperreactivity and inflammation, including the expression of interleukin-25 (IL-25), IL-33 and CCL20, IL-5 and IL-13 release, nuclear factor (NF)κB activity, p38 mitogen-activated protein kinase (MAPK) phosphorylation, accumulation of eosinophils, T lymphocytes and myeloid dendritic cells, and the number of mucus-producing cells. MID1 inhibition also limited rhinovirus-induced exacerbation of allergic airway disease. We found that MID1 was upregulated in primary human bronchial epithelial cells upon HDM or rhinovirus exposure, and this correlated with TRAIL and CCL20 expression. Together, these findings identify a key role of MID1 in allergic airway inflammation and links innate immune pathway activation to the development and exacerbation of asthma.
Collapse
Affiliation(s)
- Adam Collison
- Experimental and Translational Respiratory Group, University of Newcastle and Hunter Medical Research Institute, Newcastle, New South Wales, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Nizamutdinova IT, Guleria RS, Singh AB, Kendall JA, Baker KM, Pan J. Retinoic acid protects cardiomyocytes from high glucose-induced apoptosis through inhibition of NF-κB signaling pathway. J Cell Physiol 2013; 228:380-92. [PMID: 22718360 DOI: 10.1002/jcp.24142] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We have previously shown that retinoic acid (RA) has protective effects on high glucose (HG)-induced cardiomyocyte apoptosis. To further elucidate the molecular mechanisms of RA effects, we determined the interaction between nuclear factor (NF)-κB and RA signaling. HG induced a sustained phosphorylation of IKK/IκBα and transcriptional activation of NF-κB in cardiomyocytes. Activated NF-κB signaling has an important role in HG-induced cardiomyocyte apoptosis and gene expression of interleukin-6 (IL-6), tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein-1 (MCP-1). All-trans RA (ATRA) and LGD1069, through activation of RAR/RXR-mediated signaling, inhibited the HG-mediated effects in cardiomyocytes. The inhibitory effect of RA on NF-κB activation was mediated through inhibition of IKK/IκBα phosphorylation. ATRA and LGD1069 treatment promoted protein phosphatase 2A (PP2A) activity, which was significantly suppressed by HG stimulation. The RA effects on IKK and IκBα were blocked by okadaic acid or silencing the expression of PP2Ac-subunit, indicating that the inhibitory effect of RA on NF-κB is regulated through activation of PP2A and subsequent dephosphorylation of IKK/IκBα. Moreover, ATRA and LGD1069 reversed the decreased PP2A activity and inhibited the activation of IKK/IκBα and gene expression of MCP-1, IL-6, and TNF-α in the hearts of Zucker diabetic fatty rats. In summary, our findings suggest that the suppressed activation of PP2A contributed to sustained activation of NF-κB in HG-stimulated cardiomyocytes; and that the protective effect of RA on hyperglycemia-induced cardiomyocyte apoptosis and inflammatory responses is partially regulated through activation of PP2A and suppression of NF-κB-mediated signaling and downstream targets.
Collapse
Affiliation(s)
- Irina T Nizamutdinova
- Division of Molecular Cardiology, Department of Medicine, College of Medicine, Texas A&M Health Science Center, Temple, Texas 76504, USA
| | | | | | | | | | | |
Collapse
|
19
|
Rietz A, Volkov Y, Davies A, Hennessy M, Spiers JP. Okadaic acid induces matrix metalloproteinase-9 expression in fibroblasts: crosstalk between protein phosphatase inhibition and β-adrenoceptor signalling. Br J Pharmacol 2012; 165:274-88. [PMID: 21718298 DOI: 10.1111/j.1476-5381.2011.01559.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE Interactions between protein phosphatase inhibition and matrix metalloproteinase (MMP)-9 expression have implications for tissue remodelling after injury. Stimulation of β-adrenoceptors could affect such interactions as isoprenaline increases protein phosphatase 2A (PP2A) activity and MMP-9 abundance. We investigated the effect of okadaic acid (OA) on MMP-9 expression to assess interactions between phosphatase inhibition and β-adrenoceptor signalling in fibroblasts. EXPERIMENTAL APPROACH Fibroblasts were exposed to OA alone and in combination with isoprenaline. Effects on MMP-9 expression and intracellular signalling were studied using promoter assays, Western blot analysis and siRNA methodologies. KEY RESULTS Okadaic acid increased MMP-9 abundance in human cardiac ventricular fibroblasts, NIH3T3 fibroblasts and hepatic stellate cells. This effect was unaffected by PP2A knockdown in NIH3T3 cells. OA increased phosphorylation of NF-κB, but not NF-κB promoter activity, IκBα degradation, or nuclear translocation of p65-NF-κB. Exposure to SB202190 (p38 MAPK), U0126 (ERK1/2) and NF-κB III inhibitor revealed that OA induced MMP-9 activity through p38 MAPK. Isoprenaline inhibited OA-mediated MMP-9 expression in NIH3T3, in a β-arrestin 2- and PP2A-dependent manner. Mutation of the activator protein-1 (AP-1) and NF-κB binding sites demonstrated that OA-induced MMP-9 activity was mediated through the AP-1 but not NF-κB sites. The latter mediated the inhibitory effect of isoprenaline on OA-induced MMP-9 promoter activity. CONCLUSION AND IMPLICATIONS Okadaic acid induced MMP-9 activity through p38 MAPK and was inhibited by isoprenaline via a pathway involving β-arrestin 2, PP2A and an NF-κB binding motif. These findings elucidate how phosphoprotein phosphatases and adrenoceptors may modulate tissue remodelling by affecting fibroblast function.
Collapse
Affiliation(s)
- A Rietz
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Dublin, Ireland
| | | | | | | | | |
Collapse
|
20
|
Wallace AM, Hardigan A, Geraghty P, Salim S, Gaffney A, Thankachen J, Arellanos L, D'Armiento JM, Foronjy RF. Protein phosphatase 2A regulates innate immune and proteolytic responses to cigarette smoke exposure in the lung. Toxicol Sci 2012; 126:589-99. [PMID: 22223484 PMCID: PMC3307605 DOI: 10.1093/toxsci/kfr351] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 12/22/2011] [Indexed: 11/13/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is the primary serine-threonine phosphatase of eukaryotic cells, and changes in its activity have been linked to neoplastic and neurodegenerative diseases. However, the role of PP2A in noncancerous lung diseases such as chronic obstructive pulmonary disease (COPD) has not been previously examined. This study determined that PP2A activity was significantly increased in the lungs of advanced emphysema subjects compared with age-matched controls. Furthermore, we found that cigarette smoke exposure increases PP2A activity in mouse lung in vivo and in primary human small airway epithelial (SAE) cells in vitro. In mice, intratracheal transfection of PP2A protein prior to cigarette smoke exposure prevented acute smoke-induced lung inflammation. Conversely, inhibiting PP2A activity during smoke exposure exacerbated inflammatory responses in the lung. To further determine how PP2A modulates the responses to cigarette smoke in the lung, enzyme levels were manipulated in SAE cells using protein transfection and short hairpin RNA (shRNA) techniques. Increasing PP2A activity in SAE cells via PP2A protein transfection downregulated cytokine expression and prevented the induction of proteases following cigarette smoke extract (CSE) treatment. Conversely, decreasing enzymatic activity by stably transfecting SAE cells with shRNA for the A subunit of PP2A exacerbated these smoke-mediated responses. This study establishes that PP2A induction by cigarette smoke modulates immune and proteolytic responses to cigarette smoke exposure. Together, these findings suggest that manipulation of PP2A activity may be a plausible means to treat COPD and other inflammatory diseases.
Collapse
Affiliation(s)
- Alison M. Wallace
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Andrew Hardigan
- Division of Pulmonary and Critical Care Medicine, St. Luke's Roosevelt Health Sciences Center, New York, New York 10019
| | - Patrick Geraghty
- Division of Pulmonary and Critical Care Medicine, St. Luke's Roosevelt Health Sciences Center, New York, New York 10019
| | - Shaneeza Salim
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Adam Gaffney
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Jincy Thankachen
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Leo Arellanos
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Jeanine M. D'Armiento
- Department of Medicine, Division of Molecular Medicine, Columbia University, New York, New York 10032
| | - Robert F. Foronjy
- Division of Pulmonary and Critical Care Medicine, St. Luke's Roosevelt Health Sciences Center, New York, New York 10019
| |
Collapse
|
21
|
PP2A inhibitors induce apoptosis in pancreatic cancer cell line PANC-1 through persistent phosphorylation of IKKα and sustained activation of the NF-κB pathway. Cancer Lett 2011; 304:117-27. [PMID: 21376459 DOI: 10.1016/j.canlet.2011.02.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 09/21/2010] [Accepted: 02/09/2011] [Indexed: 11/20/2022]
Abstract
Serine/threonine protein phosphatase 2A (PP2A), is thought to be a cancer suppresser, as inhibition of PP2A can induce phosphorylation and activation of substrate kinases, most of which can accelerate growth. Interestingly, cantharidin potently inhibits PP2A but efficiently represses various cancer cells. In the present study, we found that PP2A inhibitors, cantharidin or Okadaic acid, inhibited cell viability and triggered apoptosis in PANC-1 pancreatic cancer cell line dependent on PP2A/IKKα/IκBα/p65 NF-κB pathway. The activation of NF-κB pathway up-regulated downstream pro-apoptotic genes, TNF-α, TRAILR1 and TRAILR2, and triggered apoptosis through the extrinsic pathway, indicating that PP2A is a potential target for pancreatic cancer treatment.
Collapse
|
22
|
Qureshi A, Subathra M, Grey A, Schey K, Del Poeta M, Luberto C. Role of sphingomyelin synthase in controlling the antimicrobial activity of neutrophils against Cryptococcus neoformans. PLoS One 2010; 5:e15587. [PMID: 21203393 PMCID: PMC3011003 DOI: 10.1371/journal.pone.0015587] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 11/16/2010] [Indexed: 11/18/2022] Open
Abstract
The key host cellular pathway(s) necessary to control the infection caused by inhalation of the environmental fungal pathogen Cryptococcus neoformans are still largely unknown. Here we have identified that the sphingolipid pathway in neutrophils is required for them to exert their killing activity on the fungus. In particular, using both pharmacological and genetic approaches, we show that inhibition of sphingomyelin synthase (SMS) activity profoundly impairs the killing ability of neutrophils by preventing the extracellular release of an antifungal factor(s). We next found that inhibition of protein kinase D (PKD), which controls vesicular sorting and secretion and is regulated by diacylglycerol (DAG) produced by SMS, totally blocks the extracellular killing activity of neutrophils against C. neoformans. The expression of SMS genes, SMS activity and the levels of the lipids regulated by SMS (namely sphingomyelin (SM) and DAG) are up-regulated during neutrophil differentiation. Finally, tissue imaging of lungs infected with C. neoformans using matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS), revealed that specific SM species are associated with neutrophil infiltration at the site of the infection. This study establishes a key role for SMS in the regulation of the killing activity of neutrophils against C. neoformans through a DAG-PKD dependent mechanism, and provides, for the first time, new insights into the protective role of host sphingolipids against a fungal infection.
Collapse
Affiliation(s)
- Asfia Qureshi
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Marimuthu Subathra
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Angus Grey
- Mass Spectrometry Research Center, Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kevin Schey
- Mass Spectrometry Research Center, Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Maurizio Del Poeta
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
- Departments of Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
- Division of Infectious Diseases, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail:
| | - Chiara Luberto
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| |
Collapse
|
23
|
Shifera AS. Proteins that bind to IKKgamma (NEMO) and down-regulate the activation of NF-kappaB. Biochem Biophys Res Commun 2010; 396:585-9. [PMID: 20457134 DOI: 10.1016/j.bbrc.2010.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 05/03/2010] [Indexed: 11/29/2022]
Abstract
Inhibitor of kappaB kinase (IKK) gamma (IKKgamma), also referred to as nuclear factor kappaB (NF-kappaB) essential modulator (NEMO), is an important component of the IKK complex. Following the exposure of cells to NF-kappaB-inducing stimuli, the IKK complex catalyzes the phosphorylation of inhibitor of kappaB (IkappaB) proteins, which is a critical step that leads to the activation of NF-kappaB via the canonical pathway. The exact functions of IKKgamma as part of the IKK complex have not been fully elucidated. A number of proteins have been identified as directly interacting with IKKgamma and modulating the activity of the IKK complex. This mini review covers eight proteins that have been reported to bind to IKKgamma and lead to the suppression of the activities of the IKK complex and hence result in the down-regulation of the activation of NF-kappaB. The reported mechanisms by which these interactions suppress the activation of the IKK complex include the deubiquitination of IKKgamma and competition with upstream activators for binding to IKKgamma.
Collapse
Affiliation(s)
- Amde Selassie Shifera
- Department of Ophthalmology, University of California, San Francisco, CA 94143, USA.
| |
Collapse
|
24
|
Cornell TT, Hinkovska-Galcheva V, Sun L, Cai Q, Hershenson MB, Vanway S, Shanley TP. Ceramide-dependent PP2A regulation of TNFalpha-induced IL-8 production in respiratory epithelial cells. Am J Physiol Lung Cell Mol Physiol 2009; 296:L849-56. [PMID: 19286927 DOI: 10.1152/ajplung.90516.2008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
IL-8 is a key mediator in the pathophysiology of acute lung injury. TNFalpha stimulates IL-8 production in respiratory epithelial cells by activating both the NF-kappaB and MAP kinase pathways. The precise mechanism by which these pathways are downregulated to terminate IL-8 production remains unclear. We studied the regulatory role of the serine/threonine phosphatase, PP2A, on the signaling pathways involved in IL-8 production from respiratory epithelial cells. Inhibition of PP2A using okadaic acid or gene knockdown using siRNA resulted in an augmentation of TNFalpha-induced IL-8 production. We also found that PP2A inhibition resulted in prolonged activation of JNK, p38, and ERK resulting in both increased transcriptional activation of the IL-8 promoter and posttranscriptional stabilization of IL-8 mRNA. Because TNFalpha had been shown to activate ceramide accumulation, and separate studies had linked ceramide with activation of PP2A, we hypothesized the pathway of TNFalpha-inducing ceramide to activate PP2A comprised an endogenous regulatory pathway. Inhibition of the immediate sphingomyelinase-dependent pathway as well as the de novo synthesis pathway of ceramide production reduced serine/threonine phosphatase activity and augmented IL-8 production. These data suggest that ceramide plays a role in activating PP2A to terminate ongoing IL-8 production. In summary, our data suggest that in respiratory epithelium, TNFalpha induces ceramide accumulation, resulting in subsequent activation of PP2A, which targets those kinases responsible for transcriptional activation of IL-8.
Collapse
Affiliation(s)
- Timothy T Cornell
- Division of Pediatric Critical Care Medicine, C. S. Mott Children's Hospital, Ann Arbor, MI 48109-0243, USA.
| | | | | | | | | | | | | |
Collapse
|
25
|
Saavedra A, Baltazar G, Duarte EP. Driving GDNF expression: the green and the red traffic lights. Prog Neurobiol 2008; 86:186-215. [PMID: 18824211 DOI: 10.1016/j.pneurobio.2008.09.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 06/18/2008] [Accepted: 09/03/2008] [Indexed: 01/28/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is widely recognized as a potent survival factor for dopaminergic neurons of the nigrostriatal pathway that degenerate in Parkinson's disease (PD). In animal models of PD, GDNF delivery to the striatum or the substantia nigra protects dopaminergic neurons against subsequent toxin-induced injury and rescues previously damaged neurons, promoting recovery of the motor function. Thus, GDNF was proposed as a potential therapy to PD aimed at slowing down, halting or reversing neurodegeneration, an issue addressed in previous reviews. However, the use of GDNF as a therapeutic agent for PD is hampered by the difficulty in delivering it to the brain. Another potential strategy is to stimulate the endogenous expression of GDNF, but in order to do that we need to understand how GDNF expression is regulated. The aim of this review is to do a comprehensive analysis of the state of the art on the control of endogenous GDNF expression in the nervous system, focusing mainly on the nigrostriatal pathway. We address the control of GDNF expression during development, in the adult brain and after injury, and how damaged neurons signal glial cells to up-regulate GDNF. Pharmacological agents or natural molecules that increase GDNF expression and show neuroprotective activity in animal models of PD are reviewed. We also provide an integrated overview of the signalling pathways linking receptors for these molecules to the induction of GDNF gene, which might also become targets for neuroprotective therapies in PD.
Collapse
Affiliation(s)
- Ana Saavedra
- Department of Cell Biology, Immunology and Neurosciences, Faculty of Medicine, University of Barcelona, Carrer Casanova 143, 08036 Barcelona, Spain.
| | | | | |
Collapse
|
26
|
Abstract
Controlled nucleocytoplasmic localization regulates activity of NF kappa B as well as other transcription factors. Analysis of the nucleocytoplasmic protein shuttling has been greatly facilitated by the use of leptomycin B (LMB), an inhibitor of CRM1-dependent nuclear export. The authors have previously shown that LMB inhibits NF kappa B activity in human neutrophils by increasing the nuclear accumulation of NF kappa B inhibitor, I kappa B alpha. In this chapter, the authors describe a protocol that uses LMB to study the nucleocytoplasmic shuttling of I kappa B alpha in human macrophage-like U937 cells, thus inhibiting NF kappa B activity. This protocol should be readily adaptable to analyze the nucleocytoplasmic shuttling of other proteins in human leukocytes.
Collapse
|
27
|
Chassin C, Hornef MW, Bens M, Lotz M, Goujon JM, Vimont S, Arlet G, Hertig A, Rondeau E, Vandewalle A. Hormonal control of the renal immune response and antibacterial host defense by arginine vasopressin. ACTA ACUST UNITED AC 2007; 204:2837-52. [PMID: 17967904 PMCID: PMC2118508 DOI: 10.1084/jem.20071032] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ascending urinary tract infection (UTI) and pyelonephritis caused by uropathogenic Escherichia coli (UPEC) are very common infections that can cause severe kidney damage. Collecting duct cells, the site of hormonally regulated ion transport and water absorption controlled by vasopressin, are the preferential intrarenal site of bacterial adhesion and initiation of inflammatory response. We investigated the effect of the potent V2 receptor (V2R) agonist deamino-8-D-arginine vasopressin (dDAVP) on the activation of the innate immune response using established and primary cultured collecting duct cells and an experimental model of ascending UTI. dDAVP inhibited Toll-like receptor 4–mediated nuclear factor κB activation and chemokine secretion in a V2R-specific manner. The dDAVP-mediated suppression involved activation of protein phosphatase 2A and required an intact cystic fibrosis transmembrane conductance regulator Cl− channel. In vivo infusion of dDAVP induced a marked fall in proinflammatory mediators and neutrophil recruitment, and a dramatic rise in the renal bacterial burden in mice inoculated with UPECs. Conversely, administration of the V2R antagonist SR121463B to UPEC-infected mice stimulated both the local innate response and the antibacterial host defense. These findings evidenced a novel hormonal regulation of innate immune cellular activation and demonstrate that dDAVP is a potent modulator of microbial-induced inflammation in the kidney.
Collapse
Affiliation(s)
- Cécilia Chassin
- Institut National de la Santé et de la Recherche Médicale, U773, Centre de Recherche Biomédicale Bichat-Beaujon, BP 416, 75018 Paris, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Park HY, Song MG, Lee JS, Kim JW, Jin JO, Park JI, Chang YC, Kwak JY. Apoptosis of human neutrophils induced by protein phosphatase 1/2A inhibition is caspase-independent and serine protease-dependent. J Cell Physiol 2007; 212:450-62. [PMID: 17311286 DOI: 10.1002/jcp.21039] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Protein phosphatase (PP) activity is associated with the regulation of apoptosis in neutrophils. However, the underlying regulatory mechanism(s) in apoptosis remain unclear. The type of cell death induced by okadaic acid (OA), the inhibitor of PP1 and PP2A, is characterized by apoptotic morphological changes of the cells and annexin V-positive staining without DNA fragmentation. The apoptotic effects of OA and calyculin A on neutrophils were observed at concentrations ranging from 50 to 200 nM, or 10 to 50 nM, respectively. Cyclosporine A (a PP2B specific inhibitor), however, did not exhibit any pro-apoptotic effects. OA and calyculin A, but not cyclosporine A, exhibited significant effects on protein levels and on the electrophoretic mobility of Mcl-1. zVAD-fmk, a pancaspase inhibitor, failed to inhibit the effect of OA on the caspase-3 activity, procaspase-3 processing, and the apoptotic rate of neutrophils. However, 4-(2-aminoethyl) benzenesulfonylfluoride (AEBSF), a general serine protease inhibitor, significantly abrogated the OA-induced mobility shift in procaspase-3, caspase-3 activation, and the apoptotic morphological changes in neutrophils. Moreover, OA enhanced the serine protease activity of the neutrophils. The addition of the proteinase-3 protein increased the rate of neutrophil apoptosis, which was also blocked by AEBSF but not by zVAD-fmk. These results suggest that OA induces procaspase-3 processing but that OA-induced apoptosis is caspase-independent and serine protease-dependent.
Collapse
Affiliation(s)
- Hae-Young Park
- Department of Biochemistry, School of Medicine and Medical Research Center for Cancer Molecular Therapy, Dong-A University, Busan, Korea
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Miskolci V, Rollins J, Vu HY, Ghosh CC, Davidson D, Vancurova I. NFkappaB is persistently activated in continuously stimulated human neutrophils. Mol Med 2007. [PMID: 17592547 DOI: 10.2119/2006-00072.miskolci] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Increased activation of the transcription factor NFkappaB in the neutrophils has been associated with the pathogenesis of sepsis, acute lung injury (ALI), bronchopulmonary dysplasia (BPD), and other neutrophil-mediated inflammatory disorders. Despite recent progress in analyzing early NFkappaB activation in human neutrophils, activation of NFkappaB in persistently stimulated neutrophils has not been previously studied. Because it is the persistent NFkappaB activation that is thought to be involved in the host response to sepsis and the pathogenesis of ALI and BPD, we hypothesized that continuously stimulated human neutrophils may exhibit a late phase of NFkappaB activity. The goal of this study was to analyze the NFkappaB activation and expression of IkappaB and NFkappaB proteins during neutrophil stimulation with inflammatory signals for prolonged times. We demonstrate that neutrophil stimulation with lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNFalpha) induces, in addition to the early activation at 30-60 min, a previously unrecognized late phase of NFkappaB activation. In LPS-stimulated neutrophils, this NFkappaB activity typically had a biphasic character, whereas TNFalpha-stimulated neutrophils exhibited a continuous NFkappaB activity peaking around 9 h after stimulation. In contrast to the early NFkappaB activation that inversely correlates to the nuclear levels of IkappaBalpha, however, in continuously stimulated neutrophils, NFkappaB is persistently activated despite considerable levels of IkappaBalpha present in the nucleus. Our data suggest that NFkappaB is persistently activated in human neutrophils during neutrophil-mediated inflammatory disorders, and this persistent NFkappaB activity may represent one of the underlying mechanisms for the continuous production of proinflammatory mediators.
Collapse
Affiliation(s)
- Veronika Miskolci
- Department of Biological Sciences, St. John's University, New York, NY 11439, and Center for Immunology and Inflammation, The Feinstein Institute for Medical Research, North Shore--Long Island Jewish Health System, New Hyde Park, NY, USA
| | | | | | | | | | | |
Collapse
|
30
|
Miskolci V, Rollins J, Vu HY, Ghosh CC, Davidson D, Vancurova I. NFkappaB is persistently activated in continuously stimulated human neutrophils. MOLECULAR MEDICINE (CAMBRIDGE, MASS.) 2007; 13:134-42. [PMID: 17592547 PMCID: PMC1892764 DOI: 10.2119/2006–00072.miskolci] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Accepted: 01/22/2007] [Indexed: 11/06/2022]
Abstract
Increased activation of the transcription factor NFkappaB in the neutrophils has been associated with the pathogenesis of sepsis, acute lung injury (ALI), bronchopulmonary dysplasia (BPD), and other neutrophil-mediated inflammatory disorders. Despite recent progress in analyzing early NFkappaB activation in human neutrophils, activation of NFkappaB in persistently stimulated neutrophils has not been previously studied. Because it is the persistent NFkappaB activation that is thought to be involved in the host response to sepsis and the pathogenesis of ALI and BPD, we hypothesized that continuously stimulated human neutrophils may exhibit a late phase of NFkappaB activity. The goal of this study was to analyze the NFkappaB activation and expression of IkappaB and NFkappaB proteins during neutrophil stimulation with inflammatory signals for prolonged times. We demonstrate that neutrophil stimulation with lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNFalpha) induces, in addition to the early activation at 30-60 min, a previously unrecognized late phase of NFkappaB activation. In LPS-stimulated neutrophils, this NFkappaB activity typically had a biphasic character, whereas TNFalpha-stimulated neutrophils exhibited a continuous NFkappaB activity peaking around 9 h after stimulation. In contrast to the early NFkappaB activation that inversely correlates to the nuclear levels of IkappaBalpha, however, in continuously stimulated neutrophils, NFkappaB is persistently activated despite considerable levels of IkappaBalpha present in the nucleus. Our data suggest that NFkappaB is persistently activated in human neutrophils during neutrophil-mediated inflammatory disorders, and this persistent NFkappaB activity may represent one of the underlying mechanisms for the continuous production of proinflammatory mediators.
Collapse
Affiliation(s)
- Veronika Miskolci
- Department of Biological Sciences, St. John’s University, New York
- Division of Neonatal-Perinatal Medicine, and Center for Immunology and Inflammation, The Feinstein Institute for Medical Research, North Shore – Long Island Jewish Health System, New Hyde Park, NY, USA
| | - Janet Rollins
- Department of Biological Sciences, St. John’s University, New York
| | - Hai Yen Vu
- Department of Biological Sciences, St. John’s University, New York
| | - Chandra C Ghosh
- Department of Biological Sciences, St. John’s University, New York
| | - Dennis Davidson
- Division of Neonatal-Perinatal Medicine, and Center for Immunology and Inflammation, The Feinstein Institute for Medical Research, North Shore – Long Island Jewish Health System, New Hyde Park, NY, USA
| | - Ivana Vancurova
- Department of Biological Sciences, St. John’s University, New York
- Division of Neonatal-Perinatal Medicine, and Center for Immunology and Inflammation, The Feinstein Institute for Medical Research, North Shore – Long Island Jewish Health System, New Hyde Park, NY, USA
- Address correspondence and reprint requests to Ivana Vancurova, Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, New York, NY 11439. Phone: 718-990-6409; Fax: 718-990-5958; E-mail:
| |
Collapse
|
31
|
Miskolci V, Ghosh CC, Rollins J, Romero C, Vu HY, Robinson S, Davidson D, Vancurova I. TNFalpha release from peripheral blood leukocytes depends on a CRM1-mediated nuclear export. Biochem Biophys Res Commun 2006; 351:354-60. [PMID: 17064665 DOI: 10.1016/j.bbrc.2006.10.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Accepted: 10/05/2006] [Indexed: 10/24/2022]
Abstract
Tumor necrosis factor-alpha (TNFalpha) is a potent pro-inflammatory cytokine that plays a major role in the pathogenesis of acute and chronic inflammatory disorders such as septic shock and arthritis, respectively. Leukocytes stimulated with inflammatory signals such as lipopolysaccharide (LPS) are the predominant producers of TNFalpha, and thus control of TNFalpha release from stimulated leukocytes represents a potential therapeutic target. Here, we report that leptomycin B (LMB), a specific inhibitor of CRM1-dependent nuclear protein export, inhibits TNFalpha release from LPS-stimulated human peripheral blood neutrophils and mononuclear cells. In addition, immunofluorescence confocal microscopy and immunoblotting analysis indicate that TNFalpha is localized in the nucleus of human neutrophils and mononuclear cells. This study demonstrates that the cellular release of TNFalpha from stimulated leukocytes is mediated by the CRM1-dependent nuclear export mechanism. Inhibition of CRM1-dependent cellular release of TNFalpha could thus provide a novel therapeutic approach for disorders involving excessive TNFalpha release.
Collapse
|
32
|
Morimoto H, Ozaki A, Okamura H, Yoshida K, Kitamura S, Haneji T. Okadaic acid induces tyrosine phosphorylation of IkappaBalpha that mediated by PKR pathway in human osteoblastic MG63 cells. Mol Cell Biochem 2006; 276:211-7. [PMID: 16132703 DOI: 10.1007/s11010-005-4440-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Accepted: 03/23/2005] [Indexed: 10/25/2022]
Abstract
Treatment of human osteosarcoma cell line MG 63 cells with okadaic acid stimulated phosphorylation of IkappaBalpha, as judged from the results of Western blot analysis and a lambda protein phosphatase dephosphorylation assay. The stimulated phosphorylation of IkappaBalpha was both time- and dose-dependent. The phosphorylation sites of IkappaBalpha were taken to be tyrosine residues because the anti-phospho-tyrosine antibody bound to the samples immunoprecipitated with the anti-IkappaBalpha antibody. In the cells treated with 100 nM okadaic acid consequential translocation of NF-kappaB p65 from the cytosol to the nucleus occurred. Double-stranded RNA-dependent protein kinase (PKR) is a player in the cellular antiviral response and is involved in transcriptional stimulation through activation of NF-kappaB. We investigated the functional relationship between PKR and IkappaBalpha phosphorylation by constructing MG 63 PKR K/R cells that produced a catalytically inactive mutant PKR. NF-kappaB p65 was detected in the nucleus of these cells, even in the unstimulated cells. Although IkappaBalpha was degraded phosphorylation of eIF-2 alpha, a substrate of PKR, did not occur in the mutant cells treated with okadaic acid. Our results suggest that okadaic acid-induced tyrosine phosphorylation of IkappaBalpha was mediated by PKR kinase activity, thus indicating the involvement of this kinase in the control mechanism governing the activation of NF-kappaB.
Collapse
Affiliation(s)
- Hiroyuki Morimoto
- Department of Oral and Maxillofacial Anatomy, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto, Tokushima 770-8504, Japan.
| | | | | | | | | | | |
Collapse
|
33
|
Ozaki A, Morimoto H, Tanaka H, Okamura H, Yoshida K, Amorim BR, Haneji T. Okadaic acid induces phosphorylation of p65NF-κB on serine 536 and activates NF-κB transcriptional activity in human osteoblastic MG63 cells. J Cell Biochem 2006; 99:1275-84. [PMID: 16795036 DOI: 10.1002/jcb.20873] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Nuclear factor-kappa B (NF-kappaB) is an essential transcription factor in the control of expression of genes involved in cell growth, differentiation, inflammation, and neoplastic transformation. Previously, we reported that okadaic acid (OA), which is a specific inhibitor of serine/threonine protein phosphatases, induced apoptosis in cells of human osteosarcoma cell line MG63. However, to date, it is not clear whether the phosphorylation status of NF-kappaB could be affected by the treatment with OA. In this report, we demonstrate that treatment of MG63 cells with OA enhanced the phosphorylation level of NF-kappaB, as judged from the results of Western blot analysis and a lambda protein phosphatase dephosphorylation assay. The phosphorylation level of NF-kappaB was enhanced in both time- and dose-dependent manners. In the cells treated with 100 nM OA for 3 h, consequential translocation of NF-kappaB from the cytosol to the nucleus occurred. Western blotting experiments with an anti-phospho-p65NF-kappaB antibody disclosed that the NF-kappaB was phosphorylated on serine 536. Furthermore, OA stimulated the transcriptional activity of NF-kappaB in MG63 cells, as judged from the results of a luciferase assay. Our findings indicate that OA elicit phosphorylation of NF-kappaB on serine 536 in MG63 cells, resulting in the translocation of phospho-NF-kappaB to the nucleus, thereby promoting transcriptional activity of genes.
Collapse
Affiliation(s)
- Akiko Ozaki
- Department of Histology and Oral Histology, Institute of Health Biosciences, The University of Tokushima Graduate School, Kuramoto, Tokushima 770-8504, Japan
| | | | | | | | | | | | | |
Collapse
|
34
|
Kray AE, Carter RS, Pennington KN, Gomez RJ, Sanders LE, Llanes JM, Khan WN, Ballard DW, Wadzinski BE. Positive regulation of IkappaB kinase signaling by protein serine/threonine phosphatase 2A. J Biol Chem 2005; 280:35974-82. [PMID: 16126728 DOI: 10.1074/jbc.m506093200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transcription factor NF-kappaB plays a key regulatory role in the cellular response to pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF). In the absence of TNF, NF-kappaB is sequestered in the cytoplasm by inhibitory IkappaB proteins. Phosphorylation of IkappaBby the beta-catalytic subunit of IKK, a multicomponent IkappaB kinase, targets the inhibitor for proteolytic destruction and facilitates nuclear translocation of NF-kappaB. This pathway is initiated by TNF-dependent phosphorylation of T loop serines in IKKbeta, which greatly stimulates IkappaB kinase activity. Prior in vitro mixing experiments indicate that protein serine/threonine phosphatase 2A (PP2A) can dephosphorylate these T loop serines and inactivate IKK, suggesting a negative regulatory role for PP2A in IKK signaling. Here we provided several in vivo lines of evidence indicating that PP2A plays a positive rather than a negative role in the regulation of IKK. First, TNF-induced degradation of IkappaB is attenuated in cells treated with okadaic acid or fostriecin, two potent inhibitors of PP2A. Second, PP2A forms stable complexes with IKK in untransfected mammalian cells. This interaction is critically dependent on amino acid residues 121-179 of the IKKgamma regulatory subunit. Third, deletion of the PP2A-binding site in IKKgamma attenuates T loop phosphorylation and catalytic activation of IKKbeta in cells treated with TNF. Taken together, these data provide strong evidence that the formation of IKK.PP2A complexes is required for the proper induction of IkappaB kinase activity in vivo.
Collapse
Affiliation(s)
- Arlene E Kray
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-6600, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Roach SK, Lee SB, Schorey JS. Differential activation of the transcription factor cyclic AMP response element binding protein (CREB) in macrophages following infection with pathogenic and nonpathogenic mycobacteria and role for CREB in tumor necrosis factor alpha production. Infect Immun 2005; 73:514-22. [PMID: 15618191 PMCID: PMC538945 DOI: 10.1128/iai.73.1.514-522.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies in our laboratory have shown a differential activation of the mitogen-activated protein kinases (MAPKs) in primary bone marrow-derived macrophages following infection with pathogenic Mycobacterium avium compared to the activation following infection with nonpathogenic Mycobacterium smegmatis. Additionally, M. smegmatis-infected macrophages produced significantly elevated levels of tumor necrosis factor alpha (TNF-alpha) compared to the levels produced by M. avium-infected macrophages. The TNF-alpha production was dependent on both p38 and extracellular signal-regulated kinase 1/2 (ERK 1/2) activation. However, the macrophage transcription factors downstream of the MAPKs, which were required for TNF-alpha production, remained undefined. In this study we determined that the transcription factor cyclic AMP response element binding protein (CREB) is significantly more activated in M. smegmatis-infected macrophages than in M. avium-infected macrophages. We also found that CREB activation was dependent on p38 and protein kinase A but not on ERK 1/2 or calmodulin kinase II. Moreover, mutating the cAMP-responsive element on the TNF-alpha promoter resulted in significantly diminished promoter activity following M. smegmatis infection but not M. avium infection. The inability of macrophages infected with M. avium to sustain MAPK activation and to produce high levels of TNF-alpha was due, in part, to an increase in serine/threonine phosphatase PP2A activity. Our studies are the first to demonstrate an important role for the transcription factor CREB in TNF-alpha production by mycobacterium-infected macrophages, as well as a role for M. avium's induction of PP2A phosphatase activity as a mechanism to limit macrophage activation.
Collapse
Affiliation(s)
- Shannon K Roach
- Department of Biology, University of Notre Dame, 130 Galvin Life Science Center, Notre Dame, IN 46556, USA
| | | | | |
Collapse
|
36
|
Abstract
The transcription factor NF-kappaB has been the focus of intense investigation for nearly two decades. Over this period, considerable progress has been made in determining the function and regulation of NF-kappaB, although there are nuances in this important signaling pathway that still remain to be understood. The challenge now is to reconcile the regulatory complexity in this pathway with the complexity of responses in which NF-kappaB family members play important roles. In this review, we provide an overview of established NF-kappaB signaling pathways with focus on the current state of research into the mechanisms that regulate IKK activation and NF-kappaB transcriptional activity.
Collapse
Affiliation(s)
- Matthew S Hayden
- Section of Immunobiology and Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut 06520, USA
| | | |
Collapse
|