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Giansanti M, Theinert T, Boeing SK, Haas D, Schlegel PG, Vacca P, Nazio F, Caruana I. Exploiting autophagy balance in T and NK cells as a new strategy to implement adoptive cell therapies. Mol Cancer 2023; 22:201. [PMID: 38071322 PMCID: PMC10709869 DOI: 10.1186/s12943-023-01893-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/30/2023] [Indexed: 12/18/2023] Open
Abstract
Autophagy is an essential cellular homeostasis pathway initiated by multiple stimuli ranging from nutrient deprivation to viral infection, playing a key role in human health and disease. At present, a growing number of evidence suggests a role of autophagy as a primitive innate immune form of defense for eukaryotic cells, interacting with components of innate immune signaling pathways and regulating thymic selection, antigen presentation, cytokine production and T/NK cell homeostasis. In cancer, autophagy is intimately involved in the immunological control of tumor progression and response to therapy. However, very little is known about the role and impact of autophagy in T and NK cells, the main players in the active fight against infections and tumors. Important questions are emerging: what role does autophagy play on T/NK cells? Could its modulation lead to any advantages? Could specific targeting of autophagy on tumor cells (blocking) and T/NK cells (activation) be a new intervention strategy? In this review, we debate preclinical studies that have identified autophagy as a key regulator of immune responses by modulating the functions of different immune cells and discuss the redundancy or diversity among the subpopulations of both T and NK cells in physiologic context and in cancer.
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Affiliation(s)
- Manuela Giansanti
- Immunology Research Area, Innate Lymphoid Cells Unit, Bambino Gesù Children's Hospital (IRCCS), Rome, Italy
| | - Tobias Theinert
- Department of Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Würzburg, 97080, Würzburg, Germany
| | - Sarah Katharina Boeing
- Department of Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Würzburg, 97080, Würzburg, Germany
| | - Dorothee Haas
- Department of Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Würzburg, 97080, Würzburg, Germany
| | - Paul-Gerhardt Schlegel
- Department of Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Würzburg, 97080, Würzburg, Germany
| | - Paola Vacca
- Immunology Research Area, Innate Lymphoid Cells Unit, Bambino Gesù Children's Hospital (IRCCS), Rome, Italy
| | - Francesca Nazio
- Immunology Research Area, Innate Lymphoid Cells Unit, Bambino Gesù Children's Hospital (IRCCS), Rome, Italy.
- Department of Biology, University of Rome Tor Vergata, 00133, Rome, Italy.
| | - Ignazio Caruana
- Department of Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Würzburg, 97080, Würzburg, Germany.
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Kim J, Ji S, Lee JY, Lorquin J, Orlikova-Boyer B, Cerella C, Mazumder A, Muller F, Dicato M, Detournay O, Diederich M. Marine Polyether Phycotoxin Palytoxin Induces Apoptotic Cell Death via Mcl-1 and Bcl-2 Downregulation. Mar Drugs 2023; 21:md21040233. [PMID: 37103372 PMCID: PMC10143546 DOI: 10.3390/md21040233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 03/28/2023] [Accepted: 03/28/2023] [Indexed: 04/28/2023] Open
Abstract
Palytoxin is considered one of the most potent biotoxins. As palytoxin-induced cancer cell death mechanisms remain to be elucidated, we investigated this effect on various leukemia and solid tumor cell lines at low picomolar concentrations. As palytoxin did not affect the viability of peripheral blood mononuclear cells (PBMC) from healthy donors and did not create systemic toxicity in zebrafish, we confirmed excellent differential toxicity. Cell death was characterized by a multi-parametric approach involving the detection of nuclear condensation and caspase activation assays. zVAD-sensitive apoptotic cell death was concomitant with a dose-dependent downregulation of antiapoptotic Bcl-2 family proteins Mcl-1 and Bcl-xL. Proteasome inhibitor MG-132 prevented the proteolysis of Mcl-1, whereas the three major proteasomal enzymatic activities were upregulated by palytoxin. Palytoxin-induced dephosphorylation of Bcl-2 further exacerbated the proapoptotic effect of Mcl-1 and Bcl-xL degradation in a range of leukemia cell lines. As okadaic acid rescued cell death triggered by palytoxin, protein phosphatase (PP)2A was involved in Bcl-2 dephosphorylation and induction of apoptosis by palytoxin. At a translational level, palytoxin abrogated the colony formation capacity of leukemia cell types. Moreover, palytoxin abrogated tumor formation in a zebrafish xenograft assay at concentrations between 10 and 30 pM. Altogether, we provide evidence of the role of palytoxin as a very potent and promising anti-leukemic agent, acting at low picomolar concentrations in cellulo and in vivo.
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Affiliation(s)
- Jaemyun Kim
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
| | - Seungwon Ji
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
| | - Jin-Young Lee
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
| | - Jean Lorquin
- Institut Méditerranéen d'Océanologie, 163 Avenue de Luminy, CEDEX 09, 13288 Marseille, France
| | - Barbora Orlikova-Boyer
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
- Laboratoire de Biologie Moléculaire et Cellulaire du Cancer (LBMCC), BAM3 Pavillon 2, 6A Rue Nicolas-Ernest Barblé, L-1210 Luxembourg, Luxembourg
| | - Claudia Cerella
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
- Laboratoire de Biologie Moléculaire et Cellulaire du Cancer (LBMCC), BAM3 Pavillon 2, 6A Rue Nicolas-Ernest Barblé, L-1210 Luxembourg, Luxembourg
| | - Aloran Mazumder
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
| | - Florian Muller
- Laboratoire de Biologie Moléculaire et Cellulaire du Cancer (LBMCC), BAM3 Pavillon 2, 6A Rue Nicolas-Ernest Barblé, L-1210 Luxembourg, Luxembourg
| | - Mario Dicato
- Laboratoire de Biologie Moléculaire et Cellulaire du Cancer (LBMCC), BAM3 Pavillon 2, 6A Rue Nicolas-Ernest Barblé, L-1210 Luxembourg, Luxembourg
| | - Olivier Detournay
- Planktovie SAS, 45 Rue Frédéric Joliot Curie, CEDEX 13, 13013 Marseille, France
| | - Marc Diederich
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08626, Republic of Korea
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E3 Ubiquitin Ligase Midline 1 Regulates Endothelial Cell ICAM-1 Expression and Neutrophil Adhesion in Abdominal Sepsis. Int J Mol Sci 2022; 24:ijms24010705. [PMID: 36614145 PMCID: PMC9821100 DOI: 10.3390/ijms24010705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 12/17/2022] [Accepted: 12/27/2022] [Indexed: 01/04/2023] Open
Abstract
Septic lung damage is associated with endothelial cell and neutrophil activation. This study examines the role of the E3 ubiquitin ligase midline 1 (Mid1) in abdominal sepsis. Mid1 expression was increased in endothelial cells derived from post-capillary venules in septic mice and TNF-α challenge increased Mid1 levels in endothelial cells in vitro. The siRNA-mediated knockdown of Mid1 decreased TNF-α-induced upregulation of ICAM-1 and neutrophil adhesion to endothelial cells. Moreover, Mid1 silencing reduced leukocyte adhesion in post-capillary venules in septic lungs in vivo. The silencing of Mid1 not only decreased Mid1 expression but also attenuated expression of ICAM-1 in lungs from septic mice. Lastly, TNF-α stimulation decreased PP2Ac levels in endothelial cells in vitro, which was reversed in endothelial cells pretreated with siRNA directed against Mid1. Thus, our novel data show that Mid1 is an important regulator of ICAM-1 expression and neutrophil adhesion in vitro and septic lung injury in vivo. A possible target of Mid1 is PP2Ac in endothelial cells. Targeting the Mid1-PP2Ac axis may be a useful way to reduce pathological lung inflammation in abdominal sepsis.
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Barrows ED, Blackburn MJ, Liu SV. Evolving role of immunotherapy in small cell lung cancer. Semin Cancer Biol 2022; 86:868-874. [PMID: 35192928 DOI: 10.1016/j.semcancer.2022.02.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 02/17/2022] [Indexed: 01/27/2023]
Abstract
Small cell lung cancer (SCLC) is a highly lethal subtype of lung cancer with a particularly poor prognosis. For decades, the best available systemic therapy was platinum plus etoposide chemotherapy, which offered frequent but transient responses. Survival gains were finally realized with the addition of immune checkpoint inhibitors to first-line chemotherapy. The phase III IMpower 133 trial showed that the addition of atezolizumab to chemotherapy improved survival. The subsequent CASPIAN trial demonstrated a similar benefit with durvalumab. These results quickly established chemo-immunotherapy as the preferred initial treatment for advanced SCLC, but outcomes remain poor for most patients. Here, we review the current and evolving role of immunotherapy in SCLC and outline emerging strategies poised to further elevate the standard of care.
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Affiliation(s)
- Elizabeth D Barrows
- Division of Hematology-Oncology, MedStar Georgetown University Hospital, Lombardi Comprehensive Cancer Center, Washington, DC, United States
| | - Matthew J Blackburn
- Division of Hematology-Oncology, MedStar Georgetown University Hospital, Lombardi Comprehensive Cancer Center, Washington, DC, United States
| | - Stephen V Liu
- Division of Hematology-Oncology, MedStar Georgetown University Hospital, Lombardi Comprehensive Cancer Center, Washington, DC, United States.
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Glaser D, Heinick A, Herting JR, Massing F, Müller FU, Pauls P, Rozhdestvensky TS, Schulte JS, Seidl MD, Skryabin BV, Stümpel F, Kirchhefer U. Impaired myocellular Ca 2+ cycling in protein phosphatase PP2A-B56α knockout mice is normalized by β-adrenergic stimulation. J Biol Chem 2022; 298:102362. [PMID: 35963431 PMCID: PMC9478386 DOI: 10.1016/j.jbc.2022.102362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 11/24/2022] Open
Abstract
The activity of protein phosphatase 2A (PP2A) is determined by the expression and localization of the regulatory B-subunits. PP2A-B56α is the dominant isoform of the B′-family in the heart. Its role in regulating the cardiac response to β-adrenergic stimulation is not yet fully understood. We therefore generated mice deficient in B56α to test the functional cardiac effects in response to catecholamine administration versus corresponding WT mice. We found the decrease in basal PP2A activity in hearts of KO mice was accompanied by a counter-regulatory increase in the expression of B′ subunits (β and γ) and higher phosphorylation of sarcoplasmic reticulum Ca2+ regulatory and myofilament proteins. The higher phosphorylation levels were associated with enhanced intraventricular pressure and relaxation in catheterized KO mice. In contrast, at the cellular level, we detected depressed Ca2+ transient and sarcomere shortening parameters in KO mice at basal conditions. Consistently, the peak amplitude of the L-type Ca2+ current was reduced and the inactivation kinetics of ICaL were prolonged in KO cardiomyocytes. However, we show β-adrenergic stimulation resulted in a comparable peak amplitude of Ca2+ transients and myocellular contraction between KO and WT cardiomyocytes. Therefore, we propose higher isoprenaline-induced Ca2+ spark frequencies might facilitate the normalized Ca2+ signaling in KO cardiomyocytes. In addition, the application of isoprenaline was associated with unchanged L-type Ca2+ current parameters between both groups. Our data suggest an important influence of PP2A-B56α on the regulation of Ca2+ signaling and contractility in response to β-adrenergic stimulation in the myocardium.
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Affiliation(s)
- Dennis Glaser
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Alexander Heinick
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Julius R Herting
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Fabian Massing
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Frank U Müller
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Paul Pauls
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Timofey S Rozhdestvensky
- Department of Medicine, Core Facility Transgenic Animal and Genetic Engineering Models (TRAM), University of Münster, Münster, Germany
| | - Jan S Schulte
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Matthias D Seidl
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Boris V Skryabin
- Department of Medicine, Core Facility Transgenic Animal and Genetic Engineering Models (TRAM), University of Münster, Münster, Germany
| | - Frank Stümpel
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Uwe Kirchhefer
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany.
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6
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Gergs U, Jahn T, Schulz N, Großmann C, Rueckschloss U, Demus U, Buchwalow IB, Neumann J. Protein Phosphatase 2A Improves Cardiac Functional Response to Ischemia and Sepsis. Int J Mol Sci 2022; 23:ijms23094688. [PMID: 35563079 PMCID: PMC9101092 DOI: 10.3390/ijms23094688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 11/16/2022] Open
Abstract
Reversible protein phosphorylation is a posttranslational modification of regulatory proteins involved in cardiac signaling pathways. Here, we focus on the role of protein phosphatase 2A (PP2A) for cardiac gene expression and stress response using a transgenic mouse model with cardiac myocyte-specific overexpression of the catalytic subunit of PP2A (PP2A-TG). Gene and protein expression were assessed under basal conditions by gene chip analysis and Western blotting. Some cardiac genes related to the cell metabolism and to protein phosphorylation such as kinases and phosphatases were altered in PP2A-TG compared to wild type mice (WT). As cardiac stressors, a lipopolysaccharide (LPS)-induced sepsis in vivo and a global cardiac ischemia in vitro (stop-flow isolated perfused heart model) were examined. Whereas the basal cardiac function was reduced in PP2A-TG as studied by echocardiography or as studied in the isolated work-performing heart, the acute LPS- or ischemia-induced cardiac dysfunction deteriorated less in PP2A-TG compared to WT. From the data, we conclude that increased PP2A activity may influence the acute stress tolerance of cardiac myocytes.
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Affiliation(s)
- Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (T.J.); (N.S.); (J.N.)
- Correspondence: ; Tel.: +49-345-557-4093
| | - Tina Jahn
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (T.J.); (N.S.); (J.N.)
| | - Nico Schulz
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (T.J.); (N.S.); (J.N.)
| | - Claudia Großmann
- Julius-Bernstein-Institut für Physiologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany;
| | - Uwe Rueckschloss
- Institut für Anatomie und Zellbiologie, Julius-Maximilians-Universität Würzburg, D-97070 Würzburg, Germany;
| | - Uta Demus
- Gesellschaft zur Förderung von Medizin-, Bio-und Umwelttechnologien e. V., D-06120 Halle, Germany;
| | - Igor B. Buchwalow
- Institut für Hämatopathologie, D-22547 Hamburg, Germany;
- Scientific and Educational Resource Center for Molecular Morphology, Peoples’ Friendship University of Russia, Moscow 117198, Russia
| | - Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (T.J.); (N.S.); (J.N.)
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7
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Chen S, Chen L, Ye L, Jiang Y, Li Q, Zhang H, Zhang R, Li H, Yu D, Zhang R, Niu Y, Zhao Q, Liu J, Ouyang G, Aschner M, Zheng Y, Zhang L, Chen W, Li D. PP2A-mTOR-p70S6K/4E-BP1 axis regulates M1 polarization of pulmonary macrophages and promotes ambient particulate matter induced mouse lung injury. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127624. [PMID: 34740159 DOI: 10.1016/j.jhazmat.2021.127624] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/10/2021] [Accepted: 10/25/2021] [Indexed: 06/13/2023]
Abstract
To identify key signaling pathways involved in ambient particulate matter (PM)-induced pulmonary injury, we generated a mouse model with myeloid-specific deletion of Ppp2r1a gene (encoding protein phosphatase 2 A (PP2A) A subunit), and conducted experiments in a real-ambient PM exposure system. PP2A Aα-/- homozygote (Aα HO) mice and matched wild-type (WT) littermates were exposed to PM over 3-week and 6-week. The effects of PM exposure on pulmonary inflammation, oxidative stress, and apoptosis were significantly enhanced in Aα HO compared to WT mice. The number of pulmonary macrophages increased by 74.8~88.0% and enhanced M1 polarization appeared in Aα HO mice upon PM exposure. Secretion of M1 macrophage-related inflammatory cytokines was significantly increased in Aα HO vs. WT mice following PM exposure. Moreover, we demonstrated that PP2A-B56α holoenzyme regulated M1 polarization and that the mTOR signaling pathway mediated the persistent M1 polarization upon PM2.5 exposure. Importantly, PP2A-B56α holoenzyme was shown to complex with mTOR/p70S6K/4E-BP1, and suppression of B56α led to enhanced phosphorylation of mTOR, p70S6K, and 4E-BP1. These observations demonstrate that the PP2A-mTOR-p70S6K/4E-BP1 signaling is a critical pathway in mediating macrophage M1 polarization, which contributes to PM-induced pulmonary injury.
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Affiliation(s)
- Shen Chen
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Liping Chen
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Lizhu Ye
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Yue Jiang
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Qiong Li
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Haiyan Zhang
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Rui Zhang
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Huiyao Li
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Dianke Yu
- Department of Toxicology, School of Public Health, Qingdao University, Qingdao 266021, China
| | - Rong Zhang
- Department of Toxicology, School of Public Health, Hebei Medical University, Shijiazhuang 050017, China
| | - Yujie Niu
- Department of Toxicology, School of Public Health, Hebei Medical University, Shijiazhuang 050017, China
| | - Qun Zhao
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, National Chromatographic Research and Analysis Center, Dalian 116023, China
| | - Jianhui Liu
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, National Chromatographic Research and Analysis Center, Dalian 116023, China
| | - Gangfeng Ouyang
- KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, Guangdong, China
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Forchheimer 209, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Yuxin Zheng
- Department of Toxicology, School of Public Health, Qingdao University, Qingdao 266021, China
| | - Lihua Zhang
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, National Chromatographic Research and Analysis Center, Dalian 116023, China
| | - Wen Chen
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Daochuan Li
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
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Elimination of negative feedback in TLR signalling allows rapid and hypersensitive detection of microbial contaminants. Sci Rep 2021; 11:24414. [PMID: 34952917 PMCID: PMC8709846 DOI: 10.1038/s41598-021-03618-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/24/2021] [Indexed: 11/17/2022] Open
Abstract
The exquisite specificity of Toll-like receptors (TLRs) to sense microbial molecular signatures is used as a powerful tool to pinpoint microbial contaminants. Various cellular systems, from native human blood cells to transfected cell lines exploit TLRs as pyrogen detectors in biological preparations. However, slow cellular responses and limited sensitivity have hampered the replacement of animal-based tests such as the rabbit pyrogen test or lipopolysaccharide detection by Limulus amoebocyte lysate. Here, we report a novel human cell-based approach to boost detection of microbial contaminants by TLR-expressing cells. By genetic and pharmacologic elimination of negative control circuits, TLR-initiated cellular responses to bacterial molecular patterns were accelerated and significantly elevated. Combining depletion of protein phosphatase PP2ACA and pharmacological inhibition of PP1 in the optimized reporter cells further enhanced the sensitivity to allow detection of bacterial lipoprotein at 30 picogram/ml. Such next-generation cellular monitoring is poised to replace animal-based testing for microbial contaminants.
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Emre C, Do KV, Jun B, Hjorth E, Alcalde SG, Kautzmann MAI, Gordon WC, Nilsson P, Bazan NG, Schultzberg M. Age-related changes in brain phospholipids and bioactive lipids in the APP knock-in mouse model of Alzheimer's disease. Acta Neuropathol Commun 2021; 9:116. [PMID: 34187579 PMCID: PMC8244172 DOI: 10.1186/s40478-021-01216-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 06/08/2021] [Indexed: 12/19/2022] Open
Abstract
Sustained brain chronic inflammation in Alzheimer’s disease (AD) includes glial cell activation, an increase in cytokines and chemokines, and lipid mediators (LMs), concomitant with decreased pro-homeostatic mediators. The inflammatory response at the onset of pathology engages activation of pro-resolving, pro-homeostatic LMs followed by a gradual decrease. We used an APP knock-in (App KI) AD mouse that accumulates β-amyloid (Aβ) and presents cognitive deficits (at 2 and 6 months of age, respectively) to investigate LMs, their precursors, biosynthetic enzymes and receptors, glial activation, and inflammatory proteins in the cerebral cortex and hippocampus at 2-, 4-, 8- and 18-month-old in comparison with wild-type (WT) mice. We used LC-mass-spectrometry and MALDI molecular imaging to analyze LMs and phospholipids, and immunochemistry for proteins. Our results revealed an age-specific lipid and cytokine profile, and glial activation in the App KI mice. Despite an early onset of Aβ pathology, pro-inflammatory and pro-resolving LMs were prominently increased only in the oldest age group. Furthermore, the LM biosynthetic enzymes increased, and their receptor expression decreased in the aged App KI mice. Arachidonic acid (AA)-containing phospholipid molecular species were elevated, correlating with decreased cPLA2 activity. MALDI molecular imaging depicted differential distribution of phospholipids according to genotype in hippocampal layers. Brain histology disclosed increased microglia proliferation starting from young age in the App KI mice, while astrocyte numbers were enhanced in older ages. Our results demonstrate that the brain lipidome is modified preferentially during aging as compared to amyloid pathology in the model studied here. However, alterations in phospholipids signal early pathological changes in membrane composition.
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Chu J, Wang J, Cui L, Liu S, An N, Han J, Che X, Wu C, Yang J. Pseudoginsenoside-F11 ameliorates okadiac acid-induced learning and memory impairment in rats via modulating protein phosphatase 2A. Mech Ageing Dev 2021; 197:111496. [PMID: 33957218 DOI: 10.1016/j.mad.2021.111496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 03/15/2021] [Accepted: 04/29/2021] [Indexed: 10/21/2022]
Abstract
We have reported that pseudoginsenoside-F11 (PF11) can significantly improve the cognitive impairments in several Alzheimer's disease (AD) models, but the mechanism has not been fully elucidated. In the present study, the effects of PF11 on AD, in particular the underlying mechanisms related with protein phosphatase 2A (PP2A), were investigated in a rat model induced by okadaic acid (OA), a selective inhibitor of PP2A. The results showed that PF11 treatment dose-dependently improved the learning and memory impairments in OA-induced AD rats. PF11 could significantly inhibit OA-induced tau hyperphosphorylation, suppress the activation of glial cells, alleviate neuroinflammation, thus rescue the neuronal and synaptic damage. Further investigation revealed that PF11 could regulate the protein expression of methyl modifying enzymes (leucine carboxyl methyltransferase-1 and protein phosphatase methylesterase-1) in the brain, thus increase methyl-PP2A protein expression and indirectly increase the activity of PP2A. Molecular docking analysis, structural alignment and in vitro results showed that PF11 was similar in the shape and electrostatic field feature to a known activator of PP2A, and could directly bind and activate PP2A. In conclusion, the present data indicate that PF11 can ameliorate OA-induced learning and memory impairment in rats via modulating PP2A.
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Affiliation(s)
- Jinxiu Chu
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Hebei Key Laboratory for Chronic Diseases, Tangshan Key Laboratory for Clinical and Basic Research on Chronic Diseases, College of Elementary Medicine, North China University of Science and Technology, Tangshan 063210, PR China
| | - Jian Wang
- Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Lijuan Cui
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Shuai Liu
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Nina An
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Jian Han
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Xiaohang Che
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Chunfu Wu
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China.
| | - Jingyu Yang
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang 110016, PR China.
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11
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Seumen CHT, Grimm TM, Hauck CR. Protein phosphatases in TLR signaling. Cell Commun Signal 2021; 19:45. [PMID: 33882943 PMCID: PMC8058998 DOI: 10.1186/s12964-021-00722-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/10/2021] [Indexed: 02/06/2023] Open
Abstract
Toll-like receptors (TLRs) are critical sensors for the detection of potentially harmful microbes. They are instrumental in initiating innate and adaptive immune responses against pathogenic organisms. However, exaggerated activation of TLR receptor signaling can also be responsible for the onset of autoimmune and inflammatory diseases. While positive regulators of TLR signaling, such as protein serine/threonine kinases, have been studied intensively, only little is known about phosphatases, which counterbalance and limit TLR signaling. In this review, we summarize protein phosphorylation events and their roles in the TLR pathway and highlight the involvement of protein phosphatases as negative regulators at specific steps along the TLR-initiated signaling cascade. Then, we focus on individual phosphatase families, specify the function of individual enzymes in TLR signaling in more detail and give perspectives for future research. A better understanding of phosphatase-mediated regulation of TLR signaling could provide novel access points to mitigate excessive immune activation and to modulate innate immune signaling.![]() Video Abstract
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Affiliation(s)
- Clovis H T Seumen
- Lehrstuhl Zellbiologie, Universität Konstanz, Universitätsstraße 10, Postablage 621, 78457, Konstanz, Germany
| | - Tanja M Grimm
- Lehrstuhl Zellbiologie, Universität Konstanz, Universitätsstraße 10, Postablage 621, 78457, Konstanz, Germany.,Konstanz Research School Chemical Biology, Universität Konstanz, 78457, Konstanz, Germany
| | - Christof R Hauck
- Lehrstuhl Zellbiologie, Universität Konstanz, Universitätsstraße 10, Postablage 621, 78457, Konstanz, Germany. .,Konstanz Research School Chemical Biology, Universität Konstanz, 78457, Konstanz, Germany.
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12
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Tadjalli A, Seven YB, Perim RR, Mitchell GS. Systemic inflammation suppresses spinal respiratory motor plasticity via mechanisms that require serine/threonine protein phosphatase activity. J Neuroinflammation 2021; 18:28. [PMID: 33468163 PMCID: PMC7816383 DOI: 10.1186/s12974-021-02074-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 01/05/2021] [Indexed: 01/05/2023] Open
Abstract
Background Inflammation undermines multiple forms of neuroplasticity. Although inflammation and its influence on plasticity in multiple neural systems has been extensively studied, its effects on plasticity of neural networks controlling vital life functions, such as breathing, are less understood. In this study, we investigated the signaling mechanisms whereby lipopolysaccharide (LPS)-induced systemic inflammation impairs plasticity within the phrenic motor system—a major spinal respiratory motor pool that drives contractions of the diaphragm muscle. Here, we tested the hypotheses that lipopolysaccharide-induced systemic inflammation (1) blocks phrenic motor plasticity by a mechanism that requires cervical spinal okadaic acid-sensitive serine/threonine protein phosphatase (PP) 1/2A activity and (2) prevents phosphorylation/activation of extracellular signal-regulated kinase 1/2 mitogen activated protein kinase (ERK1/2 MAPK)—a key enzyme necessary for the expression of phrenic motor plasticity. Methods To study phrenic motor plasticity, we utilized a well-characterized model for spinal respiratory plasticity called phrenic long-term facilitation (pLTF). pLTF is characterized by a long-lasting, progressive enhancement of inspiratory phrenic nerve motor drive following exposures to moderate acute intermittent hypoxia (mAIH). In anesthetized, vagotomized and mechanically ventilated adult Sprague Dawley rats, we examined the effect of inhibiting cervical spinal serine/threonine PP 1/2A activity on pLTF expression in sham-vehicle and LPS-treated rats. Using immunofluorescence optical density analysis, we compared mAIH-induced phosphorylation/activation of ERK 1/2 MAPK with and without LPS-induced inflammation in identified phrenic motor neurons. Results We confirmed that mAIH-induced pLTF is abolished 24 h following low-dose systemic LPS (100 μg/kg, i.p.). Cervical spinal delivery of the PP 1/2A inhibitor, okadaic acid, restored pLTF in LPS-treated rats. LPS also prevented mAIH-induced enhancement in phrenic motor neuron ERK1/2 MAPK phosphorylation. Thus, a likely target for the relevant okadaic acid-sensitive protein phosphatases is ERK1/2 MAPK or its upstream activators. Conclusions This study increases our understanding of fundamental mechanisms whereby inflammation disrupts neuroplasticity in a critical population of motor neurons necessary for breathing, and highlights key roles for serine/threonine protein phosphatases and ERK1/2 MAPK kinase in the plasticity of mammalian spinal respiratory motor circuits.
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Affiliation(s)
- Arash Tadjalli
- Breathing Research and Therapeutics Center, Department of Physical Therapy and The McKnight Brain Institute, College of Public Health & Health Professions, University of Florida, 1225 Center Drive, PO Box 100154, Gainesville, FL, 32610, USA
| | - Yasin B Seven
- Breathing Research and Therapeutics Center, Department of Physical Therapy and The McKnight Brain Institute, College of Public Health & Health Professions, University of Florida, 1225 Center Drive, PO Box 100154, Gainesville, FL, 32610, USA
| | - Raphael R Perim
- Breathing Research and Therapeutics Center, Department of Physical Therapy and The McKnight Brain Institute, College of Public Health & Health Professions, University of Florida, 1225 Center Drive, PO Box 100154, Gainesville, FL, 32610, USA
| | - Gordon S Mitchell
- Breathing Research and Therapeutics Center, Department of Physical Therapy and The McKnight Brain Institute, College of Public Health & Health Professions, University of Florida, 1225 Center Drive, PO Box 100154, Gainesville, FL, 32610, USA.
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13
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Joe Y, Chen Y, Park J, Kim HJ, Rah SY, Ryu J, Cho GJ, Choi HS, Ryter SW, Park JW, Kim UH, Chung HT. Cross-talk between CD38 and TTP Is Essential for Resolution of Inflammation during Microbial Sepsis. Cell Rep 2020; 30:1063-1076.e5. [PMID: 31995750 DOI: 10.1016/j.celrep.2019.12.090] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 10/12/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022] Open
Abstract
The resolution phase of acute inflammation is essential for tissue homeostasis, yet the underlying mechanisms remain unclear. We demonstrate that resolution of inflammation involves interactions between CD38 and tristetraprolin (TTP). During the onset of acute inflammation, CD38 levels are increased, leading to the production of Ca2+-signaling messengers, nicotinic acid adenine dinucleotide phosphate (NAADP), ADP ribose (ADPR), and cyclic ADPR (cADPR) from NAD(P)+. To initiate the onset of resolution, TTP expression is increased by the second messengers, NAADP and cADPR, which downregulate CD38 expression. The activation of TTP by Sirt1-dependent deacetylation, in response to increased NAD+ levels, suppresses the acute inflammatory response and decreases Rheb expression, inhibits mTORC1, and induces autophagolysosomes for bacterial clearance. TTP may represent a mechanistic target of anti-inflammatory agents, such as carbon monoxide. TTP mediates crosstalk between acute inflammation and autophagic clearance of bacteria from damaged tissue in the resolution of inflammation during sepsis.
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Affiliation(s)
- Yeonsoo Joe
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Yingqing Chen
- National Creative Research Laboratory for Ca(2+) signaling Network, Chonbuk National University Medical School, Jeonju 54907, Korea; Dalian University Medical College, Dalian 116622, China
| | - Jeongmin Park
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Hyo Jeong Kim
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - So-Young Rah
- National Creative Research Laboratory for Ca(2+) signaling Network, Chonbuk National University Medical School, Jeonju 54907, Korea
| | - Jinhyun Ryu
- Department of Anatomy, School of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52728, Korea
| | - Gyeong Jae Cho
- Department of Anatomy, School of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52728, Korea
| | - Hye-Seon Choi
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Stefan W Ryter
- Joan and Sanford I. Weill Department of Medicine, Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical Center, New York, NY 10065, USA
| | - Jeong Woo Park
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Uh-Hyun Kim
- National Creative Research Laboratory for Ca(2+) signaling Network, Chonbuk National University Medical School, Jeonju 54907, Korea.
| | - Hun Taeg Chung
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea.
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14
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Maggio D, Ho WS, Breese R, Walbridge S, Wang H, Cui J, Heiss JD, Gilbert MR, Kovach JS, Lu RO, Zhuang Z. Inhibition of protein phosphatase-2A with LB-100 enhances antitumor immunity against glioblastoma. J Neurooncol 2020; 148:231-244. [PMID: 32342332 DOI: 10.1007/s11060-020-03517-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 04/23/2020] [Indexed: 12/13/2022]
Abstract
PURPOSE Glioblastoma (GBM) carries a dismal prognosis despite standard multimodal treatment with surgery, chemotherapy and radiation. Immune checkpoint inhibitors, such as PD1 blockade, for treatment of GBM failed to show clinical benefit. Rational combination strategies to overcome resistance of GBM to checkpoint monotherapy are needed to extend the promise of immunotherapy to GBM management. Emerging evidence suggests that protein phosphatase 2A (PP2A) plays a critical role in the signal transduction pathways of both adaptive and innate immune cells and that inhibition of PP2A could enhance cancer immunity. We investigated the use of a PP2A inhibitor, LB-100, to enhance antitumor efficacy of PD1 blockade in a syngeneic glioma model. METHODS C57BL/6 mice were implanted with murine glioma cell line GL261-luc or GL261-WT and randomized into 4 treatment arms: (i) control, (ii) LB-100, (iii) PD1 blockade and (iv) combination. Survival was assessed and detailed profiling of tumor infiltrating leukocytes was performed. RESULTS Dual PP2A and PD1 blockade significantly improved survival compared with monotherapy alone. Combination therapy resulted in complete regression of tumors in about 25% of mice. This effect was dependent on CD4 and CD8 T cells and cured mice established antigen-specific secondary protective immunity. Analysis of tumor lymphocytes demonstrated enhanced CD8 infiltration and effector function. CONCLUSION This is the first preclinical investigation of the effect of combining PP2A inhibition with PD1 blockade for GBM. This novel combination provided effective tumor immunotherapy and long-term survival in our animal GBM model.
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Affiliation(s)
- Dominic Maggio
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Winson S Ho
- Department of Neurosurgery, Dell Medical School, University of Texas at Austin, Austin, TX, 78701, USA.
- University of Texas at Austin, 1601 Trinity St, Bldg. B HDB 3.214, Austin, TX, 78701, USA.
| | - Rebecca Breese
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Stuart Walbridge
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Herui Wang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jing Cui
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - John D Heiss
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mark R Gilbert
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - John S Kovach
- Lixte Biotechnology Holdings, Inc., East Setauket, NY, 11733, USA
| | - Rongze O Lu
- Department of Neurosurgery, Dell Medical School, University of Texas at Austin, Austin, TX, 78701, USA.
- University of Texas at Austin, 1601 Trinity St, Bldg. B HDB 3.216, Austin, TX, 78701, USA.
| | - Zhengping Zhuang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
- National Institutes of Health, BLDG 35, Rm 2B203, Bethesda, MD, 20892, USA.
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15
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Svarcbahs R, Jäntti M, Kilpeläinen T, Julku UH, Urvas L, Kivioja S, Norrbacka S, Myöhänen TT. Prolyl oligopeptidase inhibition activates autophagy via protein phosphatase 2A. Pharmacol Res 2019; 151:104558. [PMID: 31759088 DOI: 10.1016/j.phrs.2019.104558] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/02/2019] [Accepted: 11/19/2019] [Indexed: 02/06/2023]
Abstract
Prolyl oligopeptidase (PREP) is a serine protease that has been studied particularly in the context of neurodegenerative diseases for decades but its physiological function has remained unclear. We have previously found that PREP negatively regulates beclin1-mediated macroautophagy (autophagy), and that PREP inhibition by a small-molecule inhibitor induces clearance of protein aggregates in Parkinson's disease models. Since autophagy induction has been suggested as a potential therapy for several diseases, we wanted to further characterize how PREP regulates autophagy. We measured the levels of various kinases and proteins regulating beclin1-autophagy in HEK-293 and SH-SY5Y cell cultures after PREP inhibition, PREP deletion, and PREP overexpression and restoration, and verified the results in vivo by using PREP knock-out and wild-type mouse tissue where PREP was restored or overexpressed, respectively. We found that PREP regulates autophagy by interacting with protein phosphatase 2A (PP2A) and its endogenous inhibitor, protein phosphatase methylesterase 1 (PME1), and activator (protein phosphatase 2 phosphatase activator, PTPA), thus adjusting its activity and the levels of PP2A in the intracellular pool. PREP inhibition and deletion increased PP2A activity, leading to activation of death-associated protein kinase 1 (DAPK1), beclin1 phosphorylation and induced autophagy while PREP overexpression reduced this. Lowered activity of PP2A is connected to several neurodegenerative disorders and cancers, and PP2A activators would have enormous potential as drug therapy but development of such compounds has been a challenge. The concept of PREP inhibition has been proved safe, and therefore, our study supports the further development of PREP inhibitors as PP2A activators.
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Affiliation(s)
- Reinis Svarcbahs
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Maria Jäntti
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Tommi Kilpeläinen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Ulrika H Julku
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Lauri Urvas
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Saara Kivioja
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Susanna Norrbacka
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Timo T Myöhänen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland.
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16
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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: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [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.
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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.
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17
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Sun L, Hult EM, Cornell TT, Kim KK, Shanley TP, Wilke CA, Agarwal M, Gurczynski SJ, Moore BB, Dahmer MK. Loss of myeloid-specific protein phosphatase 2A enhances lung injury and fibrosis and results in IL-10-dependent sensitization of epithelial cell apoptosis. Am J Physiol Lung Cell Mol Physiol 2019; 316:L1035-L1048. [PMID: 30838865 DOI: 10.1152/ajplung.00299.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Protein phosphatase 2A (PP2A), a ubiquitously expressed Ser/Thr phosphatase is an important regulator of cytokine signaling and cell function. We previously showed that myeloid-specific deletion of PP2A (LysMcrePP2A-/-) increased mortality in a murine peritoneal sepsis model. In the current study, we assessed the role of myeloid PP2A in regulation of lung injury induced by lipopolysaccharide (LPS) or bleomycin delivered intratracheally. LysMcrePP2A-/- mice experienced increased lung injury in response to both LPS and bleomycin. LysMcrePP2A-/- mice developed more exuberant fibrosis in response to bleomycin, elevated cytokine responses, and chronic myeloid inflammation. Bone marrow-derived macrophages (BMDMs) from LysMcrePP2A-/- mice showed exaggerated inflammatory cytokine release under conditions of both M1 and M2 activation. Notably, secretion of IL-10 was elevated under all stimulation conditions, including activation of BMDMs by multiple Toll-like receptor ligands. Supernatants collected from LPS-stimulated LysMcrePP2A-/- BMDMs induced epithelial cell apoptosis in vitro but this effect was mitigated when IL-10 was also depleted from the BMDMs by crossing LysMcrePP2A-/- mice with systemic IL-10-/- mice (LysMcrePP2A-/- × IL-10-/-) or when IL-10 was neutralized. Despite these findings, IL-10 did not directly induce epithelial cell apoptosis but sensitized epithelial cells to other mediators from the BMDMs. Taken together our results demonstrate that myeloid PP2A regulates production of multiple cytokines but that its effect is most pronounced on IL-10 production. Furthermore, IL-10 sensitizes epithelial cells to apoptosis in response to myeloid-derived mediators, which likely contributes to the pathogenesis of lung injury and fibrosis in this model.
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Affiliation(s)
- Lei Sun
- Department of Pediatrics and Critical Care, University of Michigan , Ann Arbor, Michigan
| | - Elissa M Hult
- Molecular and Integrative Physiology Graduate Program, University of Michigan , Ann Arbor, Michigan
| | - Timothy T Cornell
- Department of Pediatrics and Critical Care, University of Michigan , Ann Arbor, Michigan
| | - Kevin K Kim
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan , Ann Arbor, Michigan
| | - Thomas P Shanley
- Department of Pediatrics, Northwestern University Feinberg School of Medicine and Stanley Manne Children's Research Institute at Lurie Children's Hospital , Chicago, Illinois
| | - Carol A Wilke
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan , Ann Arbor, Michigan
| | - Manisha Agarwal
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan , Ann Arbor, Michigan
| | - Stephen J Gurczynski
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan , Ann Arbor, Michigan
| | - Bethany B Moore
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan , Ann Arbor, Michigan.,Department of Microbiology and Immunology, University of Michigan , Ann Arbor, Michigan
| | - Mary K Dahmer
- Department of Pediatrics and Critical Care, University of Michigan , Ann Arbor, Michigan
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18
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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: 9] [Impact Index Per Article: 1.8] [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.
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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
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19
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Bott A, Erdem N, Lerrer S, Hotz-Wagenblatt A, Breunig C, Abnaof K, Wörner A, Wilhelm H, Münstermann E, Ben-Baruch A, Wiemann S. miRNA-1246 induces pro-inflammatory responses in mesenchymal stem/stromal cells by regulating PKA and PP2A. Oncotarget 2018; 8:43897-43914. [PMID: 28159925 PMCID: PMC5546423 DOI: 10.18632/oncotarget.14915] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 12/26/2016] [Indexed: 12/20/2022] Open
Abstract
The tumor microenvironment (TME) has an impact on breast cancer progression by creating a pro-inflammatory milieu within the tumor. However, little is known about the roles of miRNAs in cells of the TME during this process. We identified six putative oncomiRs in a breast cancer dataset, all strongly correlating with poor overall patient survival. Out of the six candidates, miR-1246 was upregulated in aggressive breast cancer subtypes and expressed at highest levels in mesenchymal stem/stroma cells (MSCs). Functionally, miR-1246 led to a p65-dependent increase in transcription and release of pro-inflammatory mediators IL-6, CCL2 and CCL5 in MSCs, and increased NF-κB activity. The pro-inflammatory phenotype of miR-1246 in MSCs was independent of TNFα stimulations and mediated by direct targeting of the tumor-suppressors PRKAR1A and PPP2CB. In vitro recapitulation of the TME revealed increased Stat3 phosphorylation in breast epithelial (MCF10A) and cancer cells (SK-BR-3, MCF7, T47D) upon incubation with conditioned medium (CM) of MSCs overexpressing miR-1246. Additionally, this stimulation enhanced proliferation of MCF10A cells, increased migration of MDA-MB-231 cells and induced attraction of THP-1 monocytic cells. Our data shows that miR-1246 acts as both key-enhancer of pro-inflammatory responses in MSCs and putative oncomiR in breast cancer, suggesting its influence on cancer-related inflammation and breast cancer progression.
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Affiliation(s)
- Alexander Bott
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Nese Erdem
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Shalom Lerrer
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Agnes Hotz-Wagenblatt
- Bioinformatics Group, Genomics & Proteomics Core Facility (GPCF), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Christian Breunig
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Khalid Abnaof
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Angelika Wörner
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Heike Wilhelm
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ewald Münstermann
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Adit Ben-Baruch
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Stefan Wiemann
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
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20
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Ravichandran S, Michelucci A, Del Sol A. Integrative Computational Network Analysis Reveals Site-Specific Mediators of Inflammation in Alzheimer's Disease. Front Physiol 2018; 9:154. [PMID: 29551980 PMCID: PMC5840953 DOI: 10.3389/fphys.2018.00154] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 02/14/2018] [Indexed: 12/02/2022] Open
Abstract
Alzheimer's disease (AD) is a major neurodegenerative disease and is one of the most common cause of dementia in older adults. Among several factors, neuroinflammation is known to play a critical role in the pathogenesis of chronic neurodegenerative diseases. In particular, studies of brains affected by AD show a clear involvement of several inflammatory pathways. Furthermore, depending on the brain regions affected by the disease, the nature and the effect of inflammation can vary. Here, in order to shed more light on distinct and common features of inflammation in different brain regions affected by AD, we employed a computational approach to analyze gene expression data of six site-specific neuronal populations from AD patients. Our network based computational approach is driven by the concept that a sustained inflammatory environment could result in neurotoxicity leading to the disease. Thus, our method aims to infer intracellular signaling pathways/networks that are likely to be constantly activated or inhibited due to persistent inflammatory conditions. The computational analysis identified several inflammatory mediators, such as tumor necrosis factor alpha (TNF-a)-associated pathway, as key upstream receptors/ligands that are likely to transmit sustained inflammatory signals. Further, the analysis revealed that several inflammatory mediators were mainly region specific with few commonalities across different brain regions. Taken together, our results show that our integrative approach aids identification of inflammation-related signaling pathways that could be responsible for the onset or the progression of AD and can be applied to study other neurodegenerative diseases. Furthermore, such computational approaches can enable the translation of clinical omics data toward the development of novel therapeutic strategies for neurodegenerative diseases.
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Affiliation(s)
- Srikanth Ravichandran
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Luxembourg, Luxembourg
| | - Alessandro Michelucci
- NORLUX Neuro-Oncology Laboratory, Department of Oncology, Luxembourg Institute of Health, Luxembourg, Luxembourg.,Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Luxembourg, Luxembourg
| | - Antonio Del Sol
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Luxembourg, Luxembourg.,Moscow Institute of Physics and Technology, Dolgoprudny, Russia
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21
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Yin J, Li R, Liu W, Chen Y, Zhang X, Li X, He X, Duan C. Neuroprotective Effect of Protein Phosphatase 2A/Tristetraprolin Following Subarachnoid Hemorrhage in Rats. Front Neurosci 2018. [PMID: 29535596 PMCID: PMC5835096 DOI: 10.3389/fnins.2018.00096] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Early brain injury (EBI) following subarachnoid hemorrhage (SAH) can lead to inflammation and neuronal dysfunction. There is a need for effective strategies to mitigate these effects and improve the outcome of patients who experience SAH. The mRNA-destabilizing protein tristetraprolin (TTP) is an anti-inflammatory factor that induces the decay of cytokine transcripts and has been implicated in diseases such as glioma. However, the mechanism of action of TTP in EBI after SAH is unclear. The present study investigated the effects of TTP regulation via phosphorylation in a rat model of SAH by protein phosphatase (PP)2A, which is a pleiotropic enzyme complex with multiple substrate phospho-proteins. We hypothesized that inhibitory phosphorylation of TTP by PP2A would reduce neuroinflammation and apoptosis. To evaluate the function of each factor, the PP2A agonist FTY720, short interfering (si)RNAs targeting TTP and PP2A were administered to rats by intracerebroventricular injection 24 h before SAH. Rats were evaluated with SAH grade, neurological score, brain water content and by western blotting, and terminal deoxynucleotidyltransferase dUTP nick-end labeling. We found that endogenous PP2A and TTP levels were increased after SAH. FTY720 induced PP2A activation would lead to dephosphorylation and activation of TTP and decreased production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8. SiRNA-mediated TTP knockdown abolished anti-inflammatory effects of FTY720 treatment, indicating that PP2A was associated with TTP activation in vivo. Decreased TNF-α, IL-6, and IL-8 levels were associated with improvement of neurological function, reduction of brain edema, suppression of caspase-3, and up-regulation of B cell lymphoma-2. These results demonstrated that PP2A activation could enhance the anti-inflammatory and anti-apoptotic effects of TTP, by which it might shed light on the development of an effective therapeutic strategy against EBI following SAH.
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Affiliation(s)
- Jian Yin
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Departments of Neurosurgery, Hanghzou Red Cross Hospital, Hangzhou, China
| | - Ran Li
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Wenchao Liu
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Yunchang Chen
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xin Zhang
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xifeng Li
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xuying He
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Chuanzhi Duan
- The National Key Clinic Specialty, The Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
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22
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Gourmaud S, Mouton-Liger F, Abadie C, Meurs EF, Paquet C, Hugon J. Dual Kinase Inhibition Affords Extended in vitro Neuroprotection in Amyloid-β Toxicity. J Alzheimers Dis 2018; 54:1659-1670. [PMID: 27636848 DOI: 10.3233/jad-160509] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In Alzheimer's disease (AD), the amyloid cascade hypothesis proposes that amyloid-beta (Aβ) neurotoxicity leads to neuroinflammation, synaptic loss, and neuronal degeneration. In AD patients, anti-amyloid immunotherapies did not succeed because they were possibly administered late in AD progression. Modulating new targets associated with Aβ toxicity, such as PKR (double-stranded RNA dependent kinase), and JNK (c-Jun N-terminal kinase) is a major goal for neuroprotection. These two pro-apoptotic kinases are activated in AD brains and involved in Aβ production, tau phosphorylation, neuroinflammation, and neuronal death. In HEK cells transfected with siRNA directed against PKR, and in PKR knockout (PKR-/-) mice neurons, we showed that PKR triggers JNK activation. Aβ-induced neuronal apoptosis, measured by cleaved PARP (Poly ADP-ribose polymerase) and cleaved caspase 3 levels, was reduced in PKR-/- neurons. Two selective JNK inhibitory peptides also produced a striking reduction of Aβ toxicity. Finally, the dual inhibition of PKR and JNK nearly abolished Aβ toxicity in primary cultured neurons. These results reveal that dual kinase inhibition can afford neuroprotection and this approach is worth being tested in in vivo AD and oxidative stress models.
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Affiliation(s)
| | | | | | - Eliane F Meurs
- Institut Pasteur, Hepacivirus and Innate Immunity Unit, Paris, France
| | - Claire Paquet
- Inserm UMR-S 942, Paris, France.,Research Memory Centre, Paris Nord Ile de France Saint Louis Lariboisière Fernand Widal Hospital, Paris, France
| | - Jacques Hugon
- Inserm UMR-S 942, Paris, France.,Research Memory Centre, Paris Nord Ile de France Saint Louis Lariboisière Fernand Widal Hospital, Paris, France
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23
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Liang D, Tian L, You R, Halpert MM, Konduri V, Baig YC, Paust S, Kim D, Kim S, Jia F, Huang S, Zhang X, Kheradmand F, Corry DB, Gilbert BE, Levitt JM, Decker WK. AIMp1 Potentiates T H1 Polarization and Is Critical for Effective Antitumor and Antiviral Immunity. Front Immunol 2018; 8:1801. [PMID: 29379495 PMCID: PMC5775236 DOI: 10.3389/fimmu.2017.01801] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 11/30/2017] [Indexed: 12/30/2022] Open
Abstract
Dendritic cells (DCs) must integrate a broad array of environmental cues to exact control over downstream immune responses including TH polarization. The multienzyme aminoacyl-tRNA synthetase complex component AIMp1/p43 responds to cellular stress and exerts pro-inflammatory functions; however, a role for DC-expressed AIMp1 in TH polarization has not previously been shown. Here, we demonstrate that the absence of AIMp1 in bone marrow-derived DC (BMDC) significantly impairs cytokine and costimulatory molecule expression, p38 MAPK signaling, and TH1 polarization of cocultured T-cells while significantly dysregulating immune-related gene expression. These deficits resulted in significantly compromised BMDC vaccine-mediated protection against melanoma. AIMp1 within the host was also critical for innate and adaptive antiviral immunity against influenza virus infection in vivo. Cancer patients with AIMp1 expression levels in the highest tertiles exhibited a 70% survival advantage at 15-year postdiagnosis as determined by bioinformatics analysis of nearly 9,000 primary human tumor samples in The Cancer Genome Atlas database. These data establish the importance of AIMp1 for the effective governance of antitumor and antiviral immune responses.
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Affiliation(s)
- Dan Liang
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Lin Tian
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States
| | - Ran You
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Matthew M Halpert
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Vanaja Konduri
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Yunyu C Baig
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Silke Paust
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States.,Department of Pediatrics, Texas Children's Hospital, Houston, TX, United States.,Center for Human Immunobiology, Texas Children's Hospital, Houston, TX, United States.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States
| | - Doyeun Kim
- Medicinal Bioconvergence Research Center, Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Fuli Jia
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States.,Antibody-based Proteomics Core, Baylor College of Medicine, Houston, TX, United States
| | - Shixia Huang
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States.,Antibody-based Proteomics Core, Baylor College of Medicine, Houston, TX, United States
| | - Xiang Zhang
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States.,Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, United States
| | - Farrah Kheradmand
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States.,Division of Pulmonary, Critical Care, and Sleep Medicine, Baylor College of Medicine, Houston, TX, United States
| | - David B Corry
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States.,Division of Immunology, Allergy, and Rheumatology, Baylor College of Medicine, Houston, TX, United States
| | - Brian E Gilbert
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States
| | - Jonathan M Levitt
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States.,Scott Department of Urology, Baylor College of Medicine, Houston, TX, United States
| | - William K Decker
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, United States.,Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, United States
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24
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Qadri M, Almadani S, Jay GD, Elsaid KA. Role of CD44 in Regulating TLR2 Activation of Human Macrophages and Downstream Expression of Proinflammatory Cytokines. THE JOURNAL OF IMMUNOLOGY 2017; 200:758-767. [PMID: 29196459 DOI: 10.4049/jimmunol.1700713] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 11/05/2017] [Indexed: 12/11/2022]
Abstract
Osteoarthritis (OA) is a low-grade chronic inflammatory joint disease. Innate immunity contributes to OA progression, mediated by TLR2 and TLR4. We evaluated the role of cluster determinant 44 (CD44), a transmembrane glycoprotein, in regulating TLR2-linked macrophage activation and resultant proinflammatory responses. TLR2 stimulation was performed on differentiated THP-1 macrophages in the presence or absence of a CD44-specific Ab or hyaluronan (HA). NF-κB nuclear translocation, IL-1 β and TNF-α gene expression, and protein concentrations were determined. Anti-CD44 Ab and HA treatments reduced NF-κB translocation, IL-1β and TNF-α expression, and production (p < 0.001). Inhibition of proinflammatory response in macrophages by HA was mediated by CD44. Protein phosphatase 2A mediated the reduction in NF-κB translocation by HA. CD44 knockdown reduced NF-κB nuclear translocation and downstream IL-1β and TNF-α protein production following TLR2 receptor stimulation (p < 0.001). CD44+/+ murine bone marrow-derived macrophages produced higher TNF-α compared with CD44-/- macrophages following TLR2 stimulation (p < 0.01). HA dose-dependently inhibited TLR2-induced TNF-α production by murine bone marrow-derived macrophages (p < 0.001). OA synovial fluids (SF) stimulated TLR2 and TLR4 receptors and induced NF-κB translocation in THP-1 macrophages. Anti-CD44 Ab treatment significantly reduced macrophage activation by OA SF (p < 0.01). CD44 regulated TLR2 responses in human macrophages, whereby a reduction in CD44 levels or engagement of CD44 by its ligand (HA) or a CD44-specific Ab reduced NF-κB translocation and downstream proinflammatory cytokine production. A CD44-specific Ab reduced macrophage activation by OA SF, and CD44 is a potentially novel target in OA treatment.
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Affiliation(s)
- Marwa Qadri
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618
| | - Sara Almadani
- Department of Pharmaceutical Sciences, Massachusetts College of Pharmacy and Health Sciences, Boston, MA 02115; and
| | - Gregory D Jay
- Department of Emergency Medicine, Rhode Island Hospital, Providence, RI 02903
| | - Khaled A Elsaid
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618;
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25
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Spigolon G, Cavaccini A, Trusel M, Tonini R, Fisone G. cJun N-terminal kinase (JNK) mediates cortico-striatal signaling in a model of Parkinson's disease. Neurobiol Dis 2017; 110:37-46. [PMID: 29107639 DOI: 10.1016/j.nbd.2017.10.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/23/2017] [Accepted: 10/27/2017] [Indexed: 10/18/2022] Open
Abstract
The cJun N-terminal kinase (JNK) signaling pathway has been extensively studied with regard to its involvement in neurodegenerative processes, but little is known about its functions in neurotransmission. In a mouse model of Parkinson's disease (PD), we show that the pharmacological activation of dopamine D1 receptors (D1R) produces a large increase in JNK phosphorylation. This effect is secondary to dopamine depletion, and is restricted to the striatal projection neurons that innervate directly the output structures of the basal ganglia (dSPN). Activation of JNK in dSPN relies on cAMP-induced phosphorylation of the dopamine- and cAMP-regulated phosphoprotein of 32kDa (DARPP-32), but does not require N-methyl-d-aspartate (NMDA) receptor transmission. Electrophysiological experiments on acute brain slices from PD mice show that inhibition of JNK signaling in dSPN prevents the increase in synaptic strength caused by activation of D1Rs. Together, our findings show that dopamine depletion confers to JNK the ability to mediate dopamine transmission, informing the future development of therapies for PD.
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Affiliation(s)
- Giada Spigolon
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Anna Cavaccini
- Neuroscience and Brain Technologies Department, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Massimo Trusel
- Neuroscience and Brain Technologies Department, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Raffaella Tonini
- Neuroscience and Brain Technologies Department, Istituto Italiano di Tecnologia, 16163 Genova, Italy.
| | - Gilberto Fisone
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden.
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26
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Targeting autophagy inhibits melanoma growth by enhancing NK cells infiltration in a CCL5-dependent manner. Proc Natl Acad Sci U S A 2017; 114:E9271-E9279. [PMID: 29078276 PMCID: PMC5676879 DOI: 10.1073/pnas.1703921114] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The failure in achieving a durable clinical immune response against cancer cells depends on the ability of cancer cells to establish a microenvironment that prevent cytotoxic immune cells to infiltrate tumors and kill cancer cells. Therefore, the key approach to achieving successful antitumor immune response is to harness strategies allowing the reorientation of immune cells to the tumor. Herein we reveal that inhibiting autophagy induces a massive infiltration of natural killer immune cells into the tumor bed, and a subsequent dramatic decrease in the tumor volume of melanomas. These results highlight the role of targeting autophagy in breaking the immunosuppressive tumor microenvironment barrier, thus allowing the infiltration of natural killer cells into the tumor to kill cancer cells. While blocking tumor growth by targeting autophagy is well established, its role on the infiltration of natural killer (NK) cells into tumors remains unknown. Here, we investigate the impact of targeting autophagy gene Beclin1 (BECN1) on the infiltration of NK cells into melanomas. We show that, in addition to inhibiting tumor growth, targeting BECN1 increased the infiltration of functional NK cells into melanoma tumors. We provide evidence that driving NK cells to the tumor bed relied on the ability of autophagy-defective tumors to transcriptionally overexpress the chemokine gene CCL5. Such infiltration and tumor regression were abrogated by silencing CCL5 in BECN1-defective tumors. Mechanistically, we show that the up-regulated expression of CCL5 occurred through the activation of its transcription factor c-Jun by a mechanism involving the impairment of phosphatase PP2A catalytic activity and the subsequent activation of JNK. Similar to BECN1, targeting other autophagy genes, such as ATG5, p62/SQSTM1, or inhibiting autophagy pharmacologically by chloroquine, also induced the expression of CCL5 in melanoma cells. Clinically, a positive correlation between CCL5 and NK cell marker NKp46 expression was found in melanoma patients, and a high expression level of CCL5 was correlated with a significant improvement of melanoma patients’ survival. We believe that this study highlights the impact of targeting autophagy on the tumor infiltration by NK cells and its benefit as a novel therapeutic approach to improve NK-based immunotherapy.
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27
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Li H, Yang D, Ning S, Xu Y, Yang F, Yin R, Feng T, Han S, Guo L, Zhang P, Qu W, Guo R, Song C, Xiao P, Zhou C, Xu Z, Sun J, Yu X. Switching of the substrate specificity of protein tyrosine phosphatase N12 by cyclin‐dependent kinase 2 phosphorylation orchestrating 2 oncogenic pathways. FASEB J 2017; 32:73-82. [PMID: 28842430 DOI: 10.1096/fj.201700418r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 08/14/2017] [Indexed: 01/27/2023]
Affiliation(s)
- Hui Li
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
- Second Hospital, Shangdong University Jinan China
| | - Duxiao Yang
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | - Shanglei Ning
- Qilu Hospital and School of Life Science, Shangdong University Jinan China
| | - Yinghui Xu
- Cancer CenterFirst Hospital of Jilin University Jilin China
| | - Fan Yang
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Rusha Yin
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Taihu Feng
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Shouqing Han
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Lu Guo
- Second Hospital, Shangdong University Jinan China
| | - Pengju Zhang
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | - Wenjie Qu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Renbo Guo
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Chen Song
- Center for Quantitative BiologyPeking University Beijing China
| | - Peng Xiao
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | | | - Zhigang Xu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
| | - Jin‐Peng Sun
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
- Duke University School of Medicine, Duke University Durham North Carolina USA
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
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28
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Ritorto MS, Rhode H, Vogel A, Borlak J. Regulation of glycosylphosphatidylinositol-anchored proteins and GPI-phospholipase D in a c-Myc transgenic mouse model of hepatocellular carcinoma and human HCC. Biol Chem 2017; 397:1147-1162. [PMID: 27232633 DOI: 10.1515/hsz-2016-0133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 05/24/2016] [Indexed: 01/13/2023]
Abstract
Recent research implicated glycosylphosphatidylinositol-anchored proteins (GPI-AP) and GPI-specific phospholipase D (GPI-PLD) in the pathogenesis of fatty liver disease and hepatocellular carcinoma (HCC). Given that c-Myc is frequently amplified in HCC, we investigated their regulation in a c-Myc transgenic disease model of liver cancer and HCC patient samples. Whole genome scans defined 54 significantly regulated genes coding for GPI-AP of which 29 and 14 were repressed in expression in transgenic tumors and steatotic human hepatocyte cultures, respectively, to influence lipid-mediated signal transduction, extracellular matrix and immunity pathways. Analysis of gene specific promoter revealed >95% to carry c-Myc binding sites thus establishing a link between c-Myc activity and transcriptional response. Alike, serum GPI-PLD activity was increased 4-fold in transgenic mice; however its tissue activity was reduced by 70%. The associated repression of the serine/threonine phosphatase 2A (PP2A), i.e. a key player of c-Myc proteolysis, indicates co-ordinate responses aimed at impairing tissue GPI-PLD anti-proliferative activities. Translational research identified >4-fold increased GPI-PLD serum protein expression though enzyme activities were repressed by 60% in NASH and HCC patients. Taken collectively, c-Myc influences GPI-AP signaling transcriptionally and posttranslational and represses GPI-AP anti-proliferative signaling in tumors. The findings broaden the perspective of molecular targeted therapies and disease monitoring.
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29
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Patel BS, Rahman MM, Rumzhum NN, Oliver BG, Verrills NM, Ammit AJ. Theophylline Represses IL-8 Secretion from Airway Smooth Muscle Cells Independently of Phosphodiesterase Inhibition. Novel Role as a Protein Phosphatase 2A Activator. Am J Respir Cell Mol Biol 2017; 54:792-801. [PMID: 26574643 DOI: 10.1165/rcmb.2015-0308oc] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Theophylline is an old drug experiencing a renaissance owing to its beneficial antiinflammatory effects in chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Multiple modes of antiinflammatory action have been reported, including inhibition of the enzymes that degrade cAMP-phosphodiesterase (PDE). Using primary cultures of airway smooth muscle (ASM) cells, we recently revealed that PDE4 inhibitors can potentiate the antiinflammatory action of β2-agonists by augmenting cAMP-dependent expression of the phosphatase that deactivates mitogen-activated protein kinase (MAPK)-MAPK phosphatase (MKP)-1. Therefore, the aim of this study was to address whether theophylline repressed cytokine production in a similar, PDE-dependent, MKP-1-mediated manner. Notably, theophylline did not potentiate cAMP release from ASM cells treated with the long-acting β2-agonist formoterol. Moreover, theophylline (0.1-10 μM) did not increase formoterol-induced MKP-1 messenger RNA expression nor protein up-regulation, consistent with the lack of cAMP generation. However, theophylline (at 10 μM) was antiinflammatory and repressed secretion of the neutrophil chemoattractant cytokine IL-8, which is produced in response to TNF-α. Because theophylline's effects were independent of PDE4 inhibition or antiinflammatory MKP-1, we then wished to elucidate the novel mechanisms responsible. We investigated the impact of theophylline on protein phosphatase (PP) 2A, a master controller of multiple inflammatory signaling pathways, and show that theophylline increases TNF-α-induced PP2A activity in ASM cells. Confirmatory results were obtained in A549 lung epithelial cells. PP2A activators have beneficial effects in ex vivo and in vivo models of respiratory disease. Thus, our study is the first to link theophylline with PP2A activation as a novel mechanism to control respiratory inflammation.
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Affiliation(s)
| | | | - Nowshin N Rumzhum
- 1 Faculty of Pharmacy, University of Sydney, New South Wales, Australia
| | - Brian G Oliver
- 2 Woolcock Institute of Medical Research, University of Sydney, New South Wales, Australia.,3 School of Life Sciences, University of Technology, Sydney, New South Wales, Australia; and
| | - Nicole M Verrills
- 4 School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, New South Wales
| | - Alaina J Ammit
- 1 Faculty of Pharmacy, University of Sydney, New South Wales, Australia
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30
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Shi Q, Xiong B, Zhong J, Wang H, Ma D, Miao C. MFHAS1 suppresses TLR4 signaling pathway via induction of PP2A C subunit cytoplasm translocation and inhibition of c-Jun dephosphorylation at Thr239. Mol Immunol 2017; 88:79-88. [PMID: 28609714 DOI: 10.1016/j.molimm.2017.06.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/30/2017] [Accepted: 06/02/2017] [Indexed: 11/20/2022]
Abstract
TLR4, an important Toll-like receptor in innate immunity, can be activated by LPS and induce proinflammatory cytokines to resist invasion of pathogenic microorganism, but excessive inflammation can trigger tissue injury. Many genes negatively regulate TLR4 signaling pathway. Recent studies found that malignant fibrous histiocytoma amplified sequence 1 (MFHAS1) suppressed the expression of cytokine IL6 in Raw264.7 cells stimulated by LPS, but the mechanisms remained unclear. This study investigated the role of MFHAS1 in TLR4 signaling pathway and the possible mechanisms implicated. The results indicated that the expression of MFHAS1 was significantly increased in cells stimulated with LPS. Up-regulation of MFHAS1 effectively suppressed inflammatory cytokine expression in cells exposed to LPS, whereas down-regulation of MFHAS1 markedly increased inflammatory cytokines expression. Co-immunoprecipitation, pull-down and immunofluorescence tests demonstrated that MFHAS1 combined with the B and C subunits of PP2A and induced cytoplasm translocation of the C subunit, leading to decrease dephosphorylation of c-Jun at Thr239 and increase degradation of c-Jun. Reduction of c-Jun protein results in decreased AP-1 activity, which is independent of inhibition of JNK or p38MAPK phosphorylation. Taken together, these results indicate that MFHAS1 suppresses TLR4 signaling pathway through induction of PP2A C subunit cytoplasm translocation and subsequent c-Jun degradation, leading finally to decrease AP-1 activity and cytokines expression.
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Affiliation(s)
- Qiqing Shi
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China; Department of Anesthesiology, Children's Hospital of Fudan University, Shanghai, 201102, China
| | - Bo Xiong
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
| | - Jing Zhong
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
| | - Huihui Wang
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
| | - Duan Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China; Children's Hospital of Fudan University, Shanghai, 201102, China.
| | - Changhong Miao
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.
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Ward MP, Spiers JP. Protein phosphatase 2A regulation of markers of extracellular matrix remodelling in hepatocellular carcinoma cells: functional consequences for tumour invasion. Br J Pharmacol 2017; 174:1116-1130. [PMID: 28239848 DOI: 10.1111/bph.13759] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 02/13/2017] [Accepted: 02/16/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND AND PURPOSE A hallmark of tumour invasion is breakdown of the extracellular matrix due to dysregulation of the matrix metalloproteinase (MMP) system. While our understanding of how this is regulated by kinase signalling pathways is well established, its counter-regulation by protein phosphatases (PP) is poorly understood. Therefore, we investigated the effect of PP inhibition on markers of extracellular remodelling and how PP2A activity modulated MMP-9 abundance and function of Hep3B cells. EXPERIMENTAL APPROACH Cells were exposed to okadaic acid (OA), tautomycetin and cyclosporin A, and the expression profile determined using PCR. Effects of OA and a protein inhibitor of PP2A, CIP2A, on MMP-9 abundance, PP2A activity and cell migration were investigated using ELISA, promoter constructs, siRNA knockdown and transwell migration assays. KEY RESULTS OA increased expression and abundance of MMP-9 and the tissue inhibitor of MMP, TIMP-1, without affecting other MMPs, TIMPs and ADAMs. The effect on MMP-9 was mimicked by CIP2A overexpression and knockdown of the PPP2CA catalytic, but not PPP2R1A scaffolding, subunit. Cyclosporin A and PPP1CA silencing did not alter MMP-9 expression, while tautomycetin transiently increased it. Mutation of AP-1, but not NF-κB, binding sites inhibited OA-mediated MMP-9 transcriptional activity. OA and CIP2A decreased PP2A activity and increased cell migration. CONCLUSION AND IMPLICATIONS OA increased MMP-9 by decreasing PP2A activity and PP2Ac, through AP-1 binding sites on the MMP-9 promoter. The functional consequence of this and CIP2A overexpression was increased cell migration. Hence, PP2A inhibition induced a metastatic phenotype through alterations in MMP-9 in Hep3B cells.
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Affiliation(s)
- M P Ward
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Dublin, Ireland
| | - J P Spiers
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Dublin, Ireland
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32
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Molecular cloning, expression and functional analysis of three subunits of protein phosphatase 2A (PP2A) from black tiger shrimps (Penaeus monodon). Comp Biochem Physiol B Biochem Mol Biol 2017; 204:77-89. [DOI: 10.1016/j.cbpb.2016.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/24/2016] [Accepted: 11/28/2016] [Indexed: 01/17/2023]
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Enjoji S, Ohama T. [The role of protein phosphatase 2A in inflammation and cancer]. Nihon Yakurigaku Zasshi 2017; 149:208-212. [PMID: 28484102 DOI: 10.1254/fpj.149.208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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34
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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: 9] [Impact Index Per Article: 1.1] [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.
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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
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Sun L, Pham TT, Cornell TT, McDonough KL, McHugh WM, Blatt NB, Dahmer MK, Shanley TP. Myeloid-Specific Gene Deletion of Protein Phosphatase 2A Magnifies MyD88- and TRIF-Dependent Inflammation following Endotoxin Challenge. THE JOURNAL OF IMMUNOLOGY 2016; 198:404-416. [PMID: 27872207 DOI: 10.4049/jimmunol.1600221] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 10/21/2016] [Indexed: 12/23/2022]
Abstract
Protein phosphatase 2A (PP2A) is a member of the intracellular serine/threonine phosphatases. Innate immune cell activation triggered by pathogen-associated molecular patterns is mediated by various protein kinases, and PP2A plays a counter-regulatory role by deactivating these kinases. In this study, we generated a conditional knockout of the α isoform of the catalytic subunit of PP2A (PP2ACα). After crossing with myeloid-specific cre-expressing mice, effective gene knockout was achieved in various myeloid cells. The myeloid-specific knockout mice (lyM-PP2Afl/fl) showed higher mortality in response to endotoxin challenge and bacterial infection. Upon LPS challenge, serum levels of TNF-α, KC, IL-6, and IL-10 were significantly increased in lyM-PP2Afl/fl mice, and increased phosphorylation was observed in MAPK pathways (p38, ERK, JNK) and the NF-κB pathway (IKKα/β, NF-κB p65) in bone marrow-derived macrophages (BMDMs) from knockout mice. Heightened NF-κB activation was not associated with degradation of IκBα; instead, enhanced phosphorylation of the NF-κB p65 subunit and p38 phosphorylation-mediated TNF-α mRNA stabilization appear to contribute to the increased TNF-α expression. In addition, increased IL-10 expression appears to be due to PP2ACα-knockout-induced IKKα/β hyperactivation. Microarray experiments indicated that the Toll/IL-1R domain-containing adaptor inducing IFN-β/ TNFR-associated factor 3 pathway was highly upregulated in LPS-treated PP2ACα-knockout BMDMs, and knockout BMDMs had elevated IFN-α/β production compared with control BMDMs. Serum IFN-β levels from PP2ACα-knockout mice treated with LPS were also greater than those in controls. Thus, we demonstrate that PP2A plays an important role in regulating inflammation and survival in the setting of septic insult by targeting MyD88- and Toll/IL-1R domain-containing adaptor inducing IFN-β-dependent pathways.
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Affiliation(s)
- Lei Sun
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109;
| | - Tiffany T Pham
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Timothy T Cornell
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Kelli L McDonough
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Walker M McHugh
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Neal B Blatt
- Division of Pediatric Nephrology, Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor, MI 48109; and
| | - Mary K Dahmer
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Thomas P Shanley
- Department of Pediatrics, Lurie Children's Hospital of Chicago, Feinberg School of Medicine, Northwestern University, Evanston, IL 60611
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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.
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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
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37
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Terna E, Luukkainen A, Seppälä M, Renkonen R, Huhtala H, Tommola S, Paavonen T, Kauppi P, Tynninen O, Jeskanen L, Toppila-Salmi S. The expression of cancerous inhibitor protein phosphatase 2A in chronic rhinosinusitis with nasal polyps. Acta Otolaryngol 2016; 136:1173-1179. [PMID: 27348236 DOI: 10.1080/00016489.2016.1195918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
CONCLUSION The study suggests that cancerous inhibitor of protein phosphatase 2A (CIP2A) expression and eosinophilia associate with chronic rhinosinusitis with nasal polyps with aspirin exacerbated respiratory disease (CRSwNP + AERD). Further studies with a larger sample size are needed to evaluate further the role of CIP2A and related pathways in CRSwNP + AERD. OBJECTIVES Low prostaglandin E2 levels putatively associate with CRSwNP + AERD and decreased c-Myc levels. The aim of this study was to evaluate the expression and revision-predictive role of oncoprotein CIP2A, another c-Myc modulator, in CRSwNP with/without AERD, and in antrochoanal polyps. METHOD Ninety retrospective archival objective glasses of nasal polyp tissue from CRSwNP or ACP patients were used for assessing mucosal eosinophilia. Of this population, 90 archival nasal polyp specimens were available for immunohistochemical staining with a polyclonal anti-CIP2A antibody, together with 19 control nasal mucosa specimens. CIP2A staining intensity and tissue eosinophilia were assessed by two blinded observers with a light microscope. Subject characteristics from 90 patients and 19 controls were obtained from patient records and additionally by a questionnaire from controls. The follow-up data was available from patient records of 84 patients and 16 controls. RESULTS The expression of epithelial CIP2A was detected both in control inferior turbinate mucosa and nasal polyps. The expression was significantly lower in the CRSwNP + AERD group compared to controls and CRSwNP without AERD (p < 0.01). High mucosal eosinophilia associated with CRSwNP (p < 0.01). Neither CIP2A nor eosinophilia predicted the need for revision surgery (p > 0.05), whereas previous surgery, allergic rhinitis, and use of corticosteroids did predict the need for revision surgery (p < 0.05).
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38
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Higuchi S, Fujikawa R, Ikedo T, Hayashi K, Yasui M, Nagata M, Nakatsuji M, Yokode M, Minami M. EP4 Receptor-Associated Protein in Macrophages Protects against Bleomycin-Induced Pulmonary Inflammation in Mice. THE JOURNAL OF IMMUNOLOGY 2016; 197:4436-4443. [PMID: 27799315 DOI: 10.4049/jimmunol.1502618] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 09/30/2016] [Indexed: 11/19/2022]
Abstract
Excessive activation of inflammatory macrophages drives the pathogenesis of many chronic diseases. EP4 receptor-associated protein (EPRAP) has been identified as a novel, anti-inflammatory molecule in macrophages. In this study, we investigated the role of EPRAP using a murine model of bleomycin (BLM)-induced pulmonary inflammation. When compared with wild-type mice, EPRAP-deficient mice exhibited significantly higher mortality, and increased accumulation of macrophages and proinflammatory molecules in the lung 7 d post-BLM administration. Accordingly, the levels of phosphorylated p105, MEK1/2, and ERK1/2 were elevated in EPRAP-deficient alveolar macrophages following BLM administration. In contrast, macrophage-specific EPRAP overexpression decreased the production of proinflammatory cytokines and chemokines, suggesting that EPRAP in macrophages plays a key role in attenuating BLM-induced pulmonary inflammation. As EPRAP is phosphorylated after translation, we examined the role of posttranslational modifications in cellular inflammatory activation using mouse embryo fibroblasts (MEFs) expressing mutant EPRAP proteins. Expression of mutant EPRAP, in which serine-108 and serine-608 were replaced with alanine (EPRAP S108A/S608A), markedly suppressed TNF-α production in LPS-treated MEFs. Conversely, the serine phosphatase 2A (PP2A) inhibitor, cantharidic acid, increased LPS-induced TNF-α production in MEFs expressing wild-type EPRAP, but not in MEFs expressing EPRAP S108A/S608A. Immunoprecipitation analyses demonstrated that EPRAP associated with PP2A in both MEFs and alveolar macrophages from BLM-treated mice. Our data suggest that PP2A dephosphorylates EPRAP, which may be a crucial step in exertion of its anti-inflammatory properties. For these reasons, we believe the EPRAP-PP2A axis in macrophages holds the key to treating chronic inflammatory disorders.
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Affiliation(s)
- Sei Higuchi
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Risako Fujikawa
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Taichi Ikedo
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.,Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan; and
| | - Kosuke Hayashi
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.,Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan; and
| | - Mika Yasui
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Manabu Nagata
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.,Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan; and
| | - Masato Nakatsuji
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.,Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Masayuki Yokode
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Manabu Minami
- Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan;
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McHugh WM, Russell WW, Fleszar AJ, Rodenhouse PE, Rietberg SP, Sun L, Shanley TP, Cornell TT. Protein phosphatase 2A activation attenuates inflammation in murine models of acute lung injury. Am J Physiol Lung Cell Mol Physiol 2016; 311:L903-L912. [PMID: 27638902 DOI: 10.1152/ajplung.00007.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 09/11/2016] [Indexed: 12/27/2022] Open
Abstract
Acute respiratory distress syndrome (ARDS) remains a leading cause of morbidity and mortality in both adult and pediatric intensive care units. A key event in the development of ARDS is neutrophil recruitment into the lungs leading to tissue damage and destruction. Interleukin-8 (IL-8) is the major human chemokine responsible for neutrophil recruitment into the lungs. Protein phosphatase 2A (PP2A) has been shown to be a key regulator of the mitogen-activated protein kinase (MAPK) cascades, which control the production of IL-8. Previously, our laboratory employed an in vitro model to show that inhibition of PP2A results in an increase in IL-8 production in human alveolar epithelial cells. The objective of this study was to determine whether PP2A regulated this response in vivo by investigating the impact of pharmacologic activation of PP2A on chemokine production and activation of the MAPK cascade and lung injury using endotoxin- and bacterial-challenge models of ARDS in mice. N6-cyclopentyladenosine (N6-CPA) increased PP2A activity and inhibited endotoxin-induced cytokine production in a murine alveolar macrophage cell line. N6-CPA pretreatment in mice challenged with intratracheal endotoxin decreased chemokine production, reduced neutrophil infiltration, and attenuated lung injury. Following initiation of lung injury with live Pseudomonas aeruginosa, mice that received N6-CPA 4 h following bacterial challenge showed attenuated chemokine production and reduced neutrophil infiltration compared with control mice. Pharmacologic PP2A activation both limited and prevented inflammation and tissue injury in two direct injury models of ARDS. These results suggest modulation of PP2A activity as a therapeutic target in ARDS.
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Affiliation(s)
- Walker M McHugh
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - William W Russell
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Andrew J Fleszar
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Paul E Rodenhouse
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Skyler P Rietberg
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Lei Sun
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Thomas P Shanley
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
| | - Timothy T Cornell
- Division of Pediatric Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, and C. S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan
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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.
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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.
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Abstract
Protein phosphatase 2A (PP2A) plays a critical multi-faceted role in the regulation of the cell cycle. It is known to dephosphorylate over 300 substrates involved in the cell cycle, regulating almost all major pathways and cell cycle checkpoints. PP2A is involved in such diverse processes by the formation of structurally distinct families of holoenzymes, which are regulated spatially and temporally by specific regulators. Here, we review the involvement of PP2A in the regulation of three cell signaling pathways: wnt, mTOR and MAP kinase, as well as the G1→S transition, DNA synthesis and mitotic initiation. These processes are all crucial for proper cell survival and proliferation and are often deregulated in cancer and other diseases.
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Affiliation(s)
- Nathan Wlodarchak
- a McArdle Laboratory for Cancer Research, University of Wisconsin-Madison , Madison , WI , USA
| | - Yongna Xing
- a McArdle Laboratory for Cancer Research, University of Wisconsin-Madison , Madison , WI , USA
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42
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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.
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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.
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Study of Protein Phosphatase 2A (PP2A) Activity in LPS-Induced Tolerance Using Fluorescence-Based and Immunoprecipitation-Aided Methodology. Biomolecules 2015; 5:1284-301. [PMID: 26131975 PMCID: PMC4598752 DOI: 10.3390/biom5031284] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 11/23/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is one of the most abundant intracellular serine/threonine (Ser/Thr) phosphatases accounting for 1% of the total cellular protein content. PP2A is comprised of a heterodimeric core enzyme and a substrate-specific regulatory subunit. Potentially, at least seventy different compositions of PP2A exist because of variable regulatory subunit binding that accounts for various activity modulating numerous cell functions. Due to the constitutive phosphatase activity present inside cells, a sensitive assay is required to detect the changes of PP2A activity under various experimental conditions. We optimized a fluorescence assay (DIFMU assay) by combining it with prior anti-PP2A immunoprecipitation to quantify PP2A-specific phosphatase activity. It is also known that prior exposure to lipopolysaccharides (LPS) induces “immune tolerance” of the cells to subsequent stimulation. Herein we report that PP2A activity is upregulated in tolerized peritoneal macrophages, corresponding to decreased TNF-α secretion upon second LPS stimulation. We further examined the role of PP2A in the tolerance effect by using PP2ACαlox/lox;lyM-Cre conditional knockout macrophages. We found that PP2A phosphatase activity cannot be further increased by tolerance. TNF-α secretion from tolerized PP2ACαlox/lox;lyM-Cre macrophages is higher than tolerized control macrophages. Furthermore, we showed that the increased TNF-α secretion may be due to an epigenetic transcriptionally active signature on the promoter of TNF-α gene rather than regulation of the NFκB/IκB signaling pathway. These results suggest a role for increased PP2A activity in the regulation of immune tolerance.
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Rahman MM, Rumzhum NN, Morris JC, Clark AR, Verrills NM, Ammit AJ. Basal protein phosphatase 2A activity restrains cytokine expression: role for MAPKs and tristetraprolin. Sci Rep 2015; 5:10063. [PMID: 25985190 PMCID: PMC4434956 DOI: 10.1038/srep10063] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 03/26/2015] [Indexed: 12/31/2022] Open
Abstract
PP2A is a master controller of multiple inflammatory signaling pathways. It is a target in asthma; however the molecular mechanisms by which PP2A controls inflammation warrant further investigation. In A549 lung epithelial cells in vitro we show that inhibition of basal PP2A activity by okadaic acid (OA) releases restraint on MAPKs and thereby increases MAPK-mediated pro-asthmatic cytokines, including IL-6 and IL-8. Notably, PP2A inhibition also impacts on the anti-inflammatory protein - tristetraprolin (TTP), a destabilizing RNA binding protein regulated at multiple levels by p38 MAPK. Although PP2A inhibition increases TTP mRNA expression, resultant TTP protein builds up in the hyperphosphorylated inactive form. Thus, when PP2A activity is repressed, pro-inflammatory cytokines increase and anti-inflammatory proteins are rendered inactive. Importantly, these effects can be reversed by the PP2A activators FTY720 and AAL(s), or more specifically by overexpression of the PP2A catalytic subunit (PP2A-C). Moreover, PP2A plays an important role in cytokine expression in cells stimulated with TNFα; as inhibition of PP2A with OA or PP2A-C siRNA results in significant increases in cytokine production. Collectively, these data reveal the molecular mechanisms of PP2A regulation and highlight the potential of boosting the power of endogenous phosphatases as novel anti-inflammatory strategies to combat asthmatic inflammation.
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Affiliation(s)
| | | | | | - 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 University of Newcastle. NSW 2308 Australia
| | - Alaina J Ammit
- Faculty of Pharmacy University of Sydney. NSW 2006 Australia
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Collison AM, Sokulsky LA, Sherrill JD, Nightingale S, Hatchwell L, Talley NJ, Walker MM, Rothenberg ME, Mattes J. TNF-related apoptosis-inducing ligand (TRAIL) regulates midline-1, thymic stromal lymphopoietin, inflammation, and remodeling in experimental eosinophilic esophagitis. J Allergy Clin Immunol 2015; 136:971-82. [PMID: 25981737 DOI: 10.1016/j.jaci.2015.03.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 02/06/2015] [Accepted: 03/10/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND Eosinophilic esophagitis (EoE) is an inflammatory disorder of the esophagus defined by eosinophil infiltration and tissue remodeling with resulting symptoms of esophageal dysfunction. TNF-related apoptosis-inducing ligand (TRAIL) promotes inflammation through upregulation of the E3 ubiquitin-ligase midline-1 (MID1), which binds to and deactivates the catalytic subunit of protein phosphatase 2Ac, resulting in increased nuclear factor κB activation. OBJECTIVE We sought to elucidate the role of TRAIL in EoE. METHODS We used Aspergillus fumigatus to induce EoE in TRAIL-sufficient (wild-type) and TRAIL-deficient (TRAIL(-/-)) mice and targeted MID1 in the esophagus with small interfering RNA. We also treated mice with recombinant thymic stromal lymphopoietin (TSLP) and TRAIL. RESULTS TRAIL deficiency and MID1 silencing with small interfering RNA reduced esophageal eosinophil and mast cell numbers and protected against esophageal circumference enlargement, muscularis externa thickening, and collagen deposition. MID1 expression and nuclear factor κB activation were reduced in TRAIL(-/-) mice, whereas protein phosphatase 2Ac levels were increased compared with those seen in wild-type control mice. This was associated with reduced expression of CCL24, CCL11, CCL20, IL-5, IL-13, IL-25, TGFB, and TSLP. Treatment with TSLP reconstituted hallmark features of EoE in TRAIL(-/-) mice and recombinant TRAIL induced esophageal TSLP expression in vivo in the absence of allergen. Post hoc analysis of gene array data demonstrated significant upregulation of TRAIL and MID1 in a cohort of children with EoE compared with that seen in controls. CONCLUSION TRAIL regulates MID1 and TSLP, inflammation, fibrosis, smooth muscle hypertrophy, and expression of inflammatory effector chemokines and cytokines in experimental EoE.
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Affiliation(s)
- Adam M Collison
- Experimental and Translational Respiratory Medicine, 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.
| | - Leon A Sokulsky
- Experimental and Translational Respiratory Medicine, 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
| | - Joseph D Sherrill
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Division of Allergy and Immunology, University of Cincinnati, Cincinnati, Ohio
| | - Scott Nightingale
- Department of Gastroenterology, Newcastle Children's Hospital, Newcastle, Australia; Faculty of Health and Medicine, University of Newcastle, Newcastle, Australia
| | - Luke Hatchwell
- Experimental and Translational Respiratory Medicine, 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
| | - Nicholas J Talley
- Faculty of Health and Medicine, University of Newcastle, Newcastle, Australia
| | - Marjorie M Walker
- Faculty of Health and Medicine, University of Newcastle, Newcastle, Australia
| | - Marc E Rothenberg
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Division of Allergy and Immunology, University of Cincinnati, Cincinnati, Ohio
| | - Joerg Mattes
- Experimental and Translational Respiratory Medicine, 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; Faculty of Health and Medicine, University of Newcastle, Newcastle, Australia; Paediatric Respiratory and Sleep Medicine Department, Newcastle Children's Hospital, Kaleidoscope, Newcastle, Australia
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MicroRNA-9 regulates steroid-resistant airway hyperresponsiveness by reducing protein phosphatase 2A activity. J Allergy Clin Immunol 2015; 136:462-73. [PMID: 25772595 DOI: 10.1016/j.jaci.2014.11.044] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Revised: 11/25/2014] [Accepted: 11/26/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND Steroid-resistant asthma is a major clinical problem that is linked to activation of innate immune cells. Levels of IFN-γ and LPS are often increased in these patients. Cooperative signaling between IFN-γ/LPS induces macrophage-dependent steroid-resistant airway hyperresponsiveness (AHR) in mouse models. MicroRNAs (miRs) are small noncoding RNAs that regulate the function of innate immune cells by controlling mRNA stability and translation. Their role in regulating glucocorticoid responsiveness and AHR remains unexplored. OBJECTIVE IFN-γ and LPS synergistically increase the expression of miR-9 in macrophages and lung tissue, suggesting a role in the mechanisms of steroid resistance. Here we demonstrate the role of miR-9 in IFN-γ/LPS-induced inhibition of dexamethasone (DEX) signaling in macrophages and in induction of steroid-resistant AHR. METHODS MiRNA-9 expression was assessed by means of quantitative RT-PCR. Putative miR-9 targets were determined in silico and confirmed in luciferase reporter assays. miR-9 function was inhibited with sequence-specific antagomirs. The efficacy of DEX was assessed by quantifying glucocorticoid receptor (GR) cellular localization, protein phosphatase 2A (PP2A) activity, and AHR. RESULTS Exposure of pulmonary macrophages to IFN-γ/LPS synergistically induced miR-9 expression; reduced levels of its target transcript, protein phosphatase 2 regulatory subunit B (B56) δ isoform; attenuated PP2A activity; and inhibited DEX-induced GR nuclear translocation. Inhibition of miR-9 increased both PP2A activity and GR nuclear translocation in macrophages and restored steroid sensitivity in multiple models of steroid-resistant AHR. Pharmacologic activation of PP2A restored DEX efficacy and inhibited AHR. MiR-9 expression was increased in sputum of patients with neutrophilic but not those with eosinophilic asthma. CONCLUSION MiR-9 regulates GR signaling and steroid-resistant AHR. Targeting miR-9 function might be a novel approach for the treatment of steroid-resistant asthma.
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Colón-Bolea P, Crespo P. Lysine methylation in cancer: SMYD3-MAP3K2 teaches us new lessons in the Ras-ERK pathway. Bioessays 2014; 36:1162-9. [PMID: 25382779 DOI: 10.1002/bies.201400120] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lysine methylation has been traditionally associated with histones and epigenetics. Recently, lysine methyltransferases and demethylases - which are involved in methylation of non-histone substrates - have been frequently found deregulated in human tumours. In this realm, a new discovery has unveiled the methyltransferase SMYD3 as an enhancer of Ras-driven cancer. SMYD3 is up-regulated in different types of tumours. SMYD3-mediated methylation of MAP3K2 increases mutant K-Ras-induced activation of ERK1/2. Methylation of MAP3K2 prevents it from binding to the phosphatase PP2A, thereby impeding the impact of this negative regulator on Ras-ERK1/2 signals, leading to the formation of lung and pancreatic adenocarcinomas. Furthermore, depletion of SMYD3 synergises with a MEK inhibitor, currently in clinical trials, to block Ras-driven pancreatic neoplasia. These results underscore the importance of lysine methylation in the regulation of signalling pathways relevant for tumourigenesis and endorse the development of drugs targeting unregulated lysine methylation as therapeutic agents in the struggle against cancer.
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Affiliation(s)
- Paula Colón-Bolea
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Cantabria, Santander, Spain
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Yi HX, Zhang M, Wang JY, Luo RB, Jiang SY, Wang JA. Determination of protein phosphatase type 2A in monocytes from multiple trauma patients: a potential biomarker for sepsis. J Surg Res 2014; 189:89-95. [DOI: 10.1016/j.jss.2014.02.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 02/17/2014] [Accepted: 02/22/2014] [Indexed: 12/29/2022]
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Zhang Y, Chen Y, Sun L, Liang J, Guo Z, Xu L. Protein phosphatases 2A as well as reactive oxygen species involved in tributyltin-induced apoptosis in mouse livers. ENVIRONMENTAL TOXICOLOGY 2014; 29:234-242. [PMID: 22223438 DOI: 10.1002/tox.21751] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 11/25/2011] [Indexed: 05/31/2023]
Abstract
Tributyltin (TBT), a highly toxic environmental contaminant, has been shown to induce caspase-3-dependent apoptosis in human amniotic cells through protein phosphatase 2A (PP2A) inhibition and consequent JNK activation. This in vivo study was undertaken to further verify the results derived from our previous in vitro study. Mice were orally dosed with 0, 10, 20, and 60 mg/kg of body weight TBT, and levels of PP2A, reactive oxygen species (ROS), mitogen-activated protein kinase (MAPK), Bax/Bcl-2, and caspase-3 were detected in the mouse livers. Apoptosis was also evaluated using the TUNEL assay. The results showed that PP2A activity was inhibited, ROS levels were elevated, and MAPKs including ERK, JNK, and p38 were activated in mouse livers treated with the highest dose of TBT. Additionally, the ratio of Bax/Bcl-2 was increased, caspase-3 was activated, and apoptosis in mouse livers could be detected in the highest dose group. Therefore, a possible signaling pathway in TBT-induced apoptosis in mouse livers involves PP2A inhibition and ROS elevation serving a pivotal function as upstream activators of MAPKs; activation of MAPKs in turn leads to an increase in the Bax/Bcl-2 ratio, ultimately leading to the activation of caspase-3. The results give a comprehensive and novel description of the mechanism of TBT-induced toxicity.
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Affiliation(s)
- Yali Zhang
- Department of Biochemistry and Genetics, School of medicine, Zhejiang University, 866th Yu Hang Tang Road, 310058, Hangzhou, China
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Zhang Y, Liang J, Sun L, Guo Z, Xu L. Inhibition of PP2A and the consequent activation of JNK/c-Jun are involved in tributyltin-induced apoptosis in human amnionic cells. ENVIRONMENTAL TOXICOLOGY 2013; 28:390-400. [PMID: 21626652 DOI: 10.1002/tox.20730] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 04/03/2011] [Accepted: 04/04/2011] [Indexed: 05/30/2023]
Abstract
Tributyltin (TBT), a highly toxic environmental contaminant, has been shown to induce mitochondrial-dependent apoptosis in several mammalian cells. However, the upstream signal transduction pathways involved in TBT-induced apoptosis are still not fully elucidated. In this study, the protein phosphatase (PP) 2A, microtubule organization, and mitogen-activated protein kinases (MAPKs), including JNK, p38 and their downstream transcription factors, c-Jun and ATF-2, respectively, were investigated in human amnionic cells treated by TBT. Furthermore, the activation of procaspase-3 after blocking either one of these MAPK pathways was also observed. The results showed that TBT effectively induced apoptosis characterized by caspase-3 activation. In apoptotic cells, the inhibition of PP2A activity and microtubule depolymerization was detected. Additionally, JNK and p38, as well as their downstream targets, c-Jun and ATF-2, were activated. Moreover, a JNK inhibitor, but not p38 inhibitor, significantly reduced caspase-3 activation. It can be concluded that the inhibition of PP2A may (1) play as a role in the activation of JNK and c-Jun and the concomitant promotion of microtubule depolymerization and (2) lead to the activation of caspase-3 in TBT-induced apoptotic cells. The results of this study suggest a critical role of PP2A in the TBT toxicity mechanism.
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Affiliation(s)
- Yali Zhang
- Department of Biochemistry and Genetics, School of medicine, Zhejiang University, 388 Yu Hang Tang Road, 310058, Hangzhou, China
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