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Murdock BJ, Goutman SA, Boss J, Kim S, Feldman EL. Amyotrophic Lateral Sclerosis Survival Associates With Neutrophils in a Sex-specific Manner. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2021; 8:8/2/e953. [PMID: 33531377 PMCID: PMC8057067 DOI: 10.1212/nxi.0000000000000953] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022]
Abstract
Objective To determine whether neutrophils contribute to amyotrophic lateral sclerosis
(ALS) progression, we tested the association of baseline neutrophil count on
ALS survival, whether the effect was sex specific, and whether neutrophils
accumulate in the spinal cord. Methods A prospective cohort study was conducted between June 22, 2011, and October
30, 2019. Blood leukocytes were isolated from ALS participants and
neutrophil levels assessed by flow cytometry. Participant survival outcomes
were analyzed by groups (<2 × 106, 2–4 ×
106, and >4 × 106 neutrophils/mL) with
adjustments for relevant ALS covariates and by sex. Neutrophil levels were
assessed from CNS tissue from a subset of participants. Results A total of 269 participants with ALS within 2 years of an ALS diagnosis were
included. Participants with baseline neutrophil counts over 4 ×
106/mL had a 2.1 times higher mortality rate than those with
a neutrophil count lower than 2 × 106/mL (95% CI:
1.3–3.5, p = 0.004) when adjusting for age,
sex, and other covariates. This effect was more pronounced in females, with
a hazard ratio of 3.8 (95% CI: 1.8–8.2, p =
0.001) in the >4 × 106/mL vs <2 ×
106/mL group. Furthermore, ALS participants (n = 8) had
increased neutrophils in cervical (p = 0.049) and
thoracic (p = 0.022) spinal cord segments compared
with control participants (n = 8). Conclusions Higher neutrophil counts early in ALS associate with a shorter survival in
female participants. Furthermore, neutrophils accumulate in ALS spinal cord
supporting a pathophysiologic correlate. These data justify the
consideration of immunity and sex for personalized therapeutic development
in ALS. Classification of Evidence This study provides Class III evidence that in female participants with ALS,
higher baseline neutrophil counts are associated with shorter survival.
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Affiliation(s)
- Benjamin J Murdock
- From the Department of Neurology (B.J.M., S.A.G., E.L.F.), and Department of Biostatistics (J.B., S.K.), School of Public Health, University of Michigan, Ann Arbor
| | - Stephen A Goutman
- From the Department of Neurology (B.J.M., S.A.G., E.L.F.), and Department of Biostatistics (J.B., S.K.), School of Public Health, University of Michigan, Ann Arbor.
| | - Jonathan Boss
- From the Department of Neurology (B.J.M., S.A.G., E.L.F.), and Department of Biostatistics (J.B., S.K.), School of Public Health, University of Michigan, Ann Arbor
| | - Sehee Kim
- From the Department of Neurology (B.J.M., S.A.G., E.L.F.), and Department of Biostatistics (J.B., S.K.), School of Public Health, University of Michigan, Ann Arbor
| | - Eva L Feldman
- From the Department of Neurology (B.J.M., S.A.G., E.L.F.), and Department of Biostatistics (J.B., S.K.), School of Public Health, University of Michigan, Ann Arbor
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2
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Bashant KR, Vassallo A, Herold C, Berner R, Menschner L, Subburayalu J, Kaplan MJ, Summers C, Guck J, Chilvers ER, Toepfner N. Real-time deformability cytometry reveals sequential contraction and expansion during neutrophil priming. J Leukoc Biol 2019; 105:1143-1153. [PMID: 30835869 PMCID: PMC7587463 DOI: 10.1002/jlb.ma0718-295rr] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 02/08/2019] [Accepted: 02/14/2019] [Indexed: 12/19/2022] Open
Abstract
It has become increasingly apparent that the biomechanical properties of neutrophils impact on their trafficking through the circulation and in particularly through the pulmonary capillary bed. The retention of polarized or shape-changed neutrophils in the lungs was recently proposed to contribute to acute respiratory distress syndrome pathogenesis. Accordingly, this study tested the hypothesis that neutrophil priming is coupled to morpho-rheological (MORE) changes capable of altering cell function. We employ real-time deformability cytometry (RT-DC), a recently developed, rapid, and sensitive way to assess the distribution of size, shape, and deformability of thousands of cells within seconds. During RT-DC analysis, neutrophils can be easily identified within anticoagulated "whole blood" due to their unique granularity and size, thus avoiding the need for further isolation techniques, which affect biomechanical cell properties. Hence, RT-DC is uniquely suited to describe the kinetics of MORE cell changes. We reveal that, following activation or priming, neutrophils undergo a short period of cell shrinking and stiffening, followed by a phase of cell expansion and softening. In some contexts, neutrophils ultimately recover their un-primed mechanical phenotype. The mechanism(s) underlying changes in human neutrophil size are shown to be Na+ /H+ antiport-dependent and are predicted to have profound implications for neutrophil movement through the vascular system in health and disease.
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Affiliation(s)
- Kathleen R Bashant
- Department of Medicine, University of Cambridge, Cambridge, UK
- National Institutes of Health, Bethesda, Maryland, USA
| | | | | | - Reinhard Berner
- Department of Pediatrics, University Clinic Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Leonhard Menschner
- Department of Pediatrics, University Clinic Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | | | | | | | - Jochen Guck
- Center for Molecular and Cellular Bioengineering, Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | | | - Nicole Toepfner
- Department of Pediatrics, University Clinic Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Center for Molecular and Cellular Bioengineering, Biotechnology Center, Technische Universität Dresden, Dresden, Germany
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3
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Vogt KL, Summers C, Chilvers ER, Condliffe AM. Priming and de-priming of neutrophil responses in vitro and in vivo. Eur J Clin Invest 2018; 48 Suppl 2:e12967. [PMID: 29896919 DOI: 10.1111/eci.12967] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 06/10/2018] [Indexed: 12/20/2022]
Abstract
The activation status of neutrophils can cycle from basal through primed to fully activated ("green-amber-red"), and at least in vitro, primed cells can spontaneously revert to a near basal phenotype. This broad range of neutrophil responsiveness confers extensive functional flexibility, allowing neutrophils to respond rapidly and appropriately to varied and evolving threats throughout the body. Primed and activated cells display dramatically enhanced bactericidal capacity (including augmented respiratory burst activity, degranulation and longevity), but this enhancement also confers the capacity for significant unintended tissue injury. Neutrophil priming and its consequences have been associated with adverse outcomes in a range of disease states, hence understanding the signalling processes that regulate the transition between basal and primed states (and back again) may offer new opportunities for therapeutic intervention in pathological settings. A wide array of host- and pathogen-derived molecules is able to modulate the functional status of these versatile cells. Reflecting this extensive repertoire of potential mediators, priming can be established by a range of signalling pathways (including mitogen-activated protein kinases, phosphoinositide 3-kinases, phospholipase D and calcium transients) and intracellular processes (including endocytosis, vesicle trafficking and the engagement of adhesion molecules). The signalling pathways engaged, and the exact cellular phenotype that results, vary according to the priming agent(s) to which the neutrophil is exposed and the precise environmental context. Herein we describe the signals that establish priming (in particular for enhanced respiratory burst, degranulation and prolonged lifespan) and describe the recently recognised process of de-priming, correlating in vitro observations with in vivo significance.
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Affiliation(s)
- Katja L Vogt
- Department of Infection, Immunity and Cardiovascular Diseases, University of Sheffield, Sheffield, UK.,Bateson Institute, University of Sheffield, Sheffield, UK
| | | | | | - Alison M Condliffe
- Department of Infection, Immunity and Cardiovascular Diseases, University of Sheffield, Sheffield, UK.,Bateson Institute, University of Sheffield, Sheffield, UK
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4
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Miralda I, Uriarte SM, McLeish KR. Multiple Phenotypic Changes Define Neutrophil Priming. Front Cell Infect Microbiol 2017; 7:217. [PMID: 28611952 PMCID: PMC5447094 DOI: 10.3389/fcimb.2017.00217] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/11/2017] [Indexed: 12/15/2022] Open
Abstract
Exposure to pro-inflammatory cytokines, chemokines, mitochondrial contents, and bacterial and viral products induces neutrophils to transition from a basal state into a primed one, which is currently defined as an enhanced response to activating stimuli. Although, typically associated with enhanced generation of reactive oxygen species (ROS) by the NADPH oxidase, primed neutrophils show enhanced responsiveness of exocytosis, NET formation, and chemotaxis. Phenotypic changes associated with priming also include activation of a subset of functions, including adhesion, transcription, metabolism, and rate of apoptosis. This review summarizes the breadth of phenotypic changes associated with priming and reviews current knowledge of the molecular mechanisms behind those changes. We conclude that the current definition of priming is too restrictive. Priming represents a combination of enhanced responsiveness and activated functions that regulate both adaptive and innate immune responses.
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Affiliation(s)
- Irina Miralda
- Department of Microbiology, University of Louisville School of MedicineLouisville, KY, United States
| | - Silvia M Uriarte
- Department of Microbiology, University of Louisville School of MedicineLouisville, KY, United States.,Department of Medicine, University of Louisville School of MedicineLouisville, KY, United States
| | - Kenneth R McLeish
- Department of Medicine, University of Louisville School of MedicineLouisville, KY, United States.,Robley Rex VA Medical CenterLouisville, KY, United States
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5
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Dumas E, Neagoe PE, McDonald PP, White M, Sirois MG. New Insights into the Pro-Inflammatory Activities of Ang1 on Neutrophils: Induction of MIP-1β Synthesis and Release. PLoS One 2016; 11:e0163140. [PMID: 27632174 PMCID: PMC5025150 DOI: 10.1371/journal.pone.0163140] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 09/02/2016] [Indexed: 12/28/2022] Open
Abstract
We reported the expression of angiopoietin Tie2 receptor on human neutrophils and the capacity of angiopoietins (Ang1 and Ang2) to induce pro-inflammatory activities, such as platelet-activating factor synthesis, β2-integrin activation and neutrophil migration. Recently, we observed differential effects between both angiopoietins, namely, the capacity of Ang1, but not Ang2, to promote rapid interleukin-8 synthesis and release, as well as neutrophil viability. Herein, we addressed whether Ang1 and/or Ang2 could modulate the synthesis and release of macrophage inflammatory protein-1β (MIP-1β) by neutrophils. Neutrophils were isolated from blood of healthy volunteers; intracellular and extracellular MIP-1β protein concentrations were assessed by ELISA. After 24 hours, the basal intracellular and extracellular MIP-1β protein concentrations were ≈500 and 100 pg/106 neutrophils, respectively. Treatment with Ang1 (10 nM) increased neutrophil intracellular and extracellular MIP-1β concentrations by 310 and 388% respectively. Pretreatment with PI3K (LY294002), p38 MAPK (SB203580) and MEK (U0126) inhibitors completely inhibited Ang1-mediated increase of MIP-1β intracellular and extracellular protein levels. Pretreatment with NF-κB complex inhibitors, namely Bay11-7085 and IKK inhibitor VII or with a transcription inhibitor (actinomycin D) and protein synthesis inhibitor (cycloheximide), did also abrogate Ang1-mediated increase of MIP-1β intracellular and extracellular protein levels. We validated by RT-qPCR analyses the effect of Ang1 on the induction of MIP-1β mRNA levels. Our study is the first one to report Ang1 capacity to induce MIP-1β gene expression, protein synthesis and release from neutrophils, and that these effects are mediated by PI3K, p38 MAPK and MEK activation and downstream NF-κB activation.
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Affiliation(s)
- Elizabeth Dumas
- Research center, Montreal Heart Institute, Montreal (Quebec), Canada
- Departments of pharmacology, Faculty of medicine, Université de Montréal, Montreal (Quebec), Canada
| | - Paul-Eduard Neagoe
- Research center, Montreal Heart Institute, Montreal (Quebec), Canada
- Departments of pharmacology, Faculty of medicine, Université de Montréal, Montreal (Quebec), Canada
| | - Patrick P. McDonald
- Pulmonary Division/Research, Faculty of Medicine, Université de Sherbrooke, Sherbrooke (Quebec), Canada
| | - Michel White
- Research center, Montreal Heart Institute, Montreal (Quebec), Canada
- Departments of medicine, Faculty of medicine, Université de Montréal, Montreal (Quebec), Canada
| | - Martin G. Sirois
- Research center, Montreal Heart Institute, Montreal (Quebec), Canada
- Departments of pharmacology, Faculty of medicine, Université de Montréal, Montreal (Quebec), Canada
- * E-mail:
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6
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Pantazi E, Bejaoui M, Folch-Puy E, Adam R, Roselló-Catafau J. Advances in treatment strategies for ischemia reperfusion injury. Expert Opin Pharmacother 2016; 17:169-79. [PMID: 26745388 DOI: 10.1517/14656566.2016.1115015] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Ischemia-reperfusion injury (IRI) involves a complex sequence of events and limits the outcome of various surgical interventions. Clinical trials, based on the data of experimental models, aim to prove whether a pharmacological or technical approach could be suitable to provide a beneficial effect in humans. Due to the complexity of IRI, few pharmacological treatments have been investigated in clinical Phase III. AREAS COVERED In this review we report clinical trials that test specific drugs in clinical trials of organ transplantation. These studies form part of Phase II trials and examine the administration of caspase inhibitors, P-selectin antagonist or an antioxidant component in order to attenuate cold IRI during transplantation. Moreover, we provide a brief description of drugs tested on trials of different clinical situations associated to IRI, such as the coronary artery bypass graft surgery and percutaneous coronary intervention. EXPERT OPINION Future clinical trials could be centered on the application of techniques suitable for organs with increased vulnerability toward IRI. Furthermore, the standardization of reliable biomarkers and a careful estimation of the impact of high risk factors may be the key in order to achieve a more critical evaluation of the obtained results.
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Affiliation(s)
- Eirini Pantazi
- a Experimental Hepatic Ischemia-Reperfusion Unit , Institute of Biomedical Research of Barcelona (IIBB-CSIC) , Barcelona , Spain
| | - Mohamed Bejaoui
- a Experimental Hepatic Ischemia-Reperfusion Unit , Institute of Biomedical Research of Barcelona (IIBB-CSIC) , Barcelona , Spain
| | - Emma Folch-Puy
- a Experimental Hepatic Ischemia-Reperfusion Unit , Institute of Biomedical Research of Barcelona (IIBB-CSIC) , Barcelona , Spain
| | - René Adam
- b AP-HP Hôpital Paul Brousse , Centre Hepato-Biliaire, Univ Paris-Sud Villejuif , Paris , France
| | - Joan Roselló-Catafau
- a Experimental Hepatic Ischemia-Reperfusion Unit , Institute of Biomedical Research of Barcelona (IIBB-CSIC) , Barcelona , Spain
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7
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fMLP-Induced IL-8 Release Is Dependent on NADPH Oxidase in Human Neutrophils. J Immunol Res 2015; 2015:120348. [PMID: 26634216 PMCID: PMC4655063 DOI: 10.1155/2015/120348] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 09/30/2015] [Accepted: 10/07/2015] [Indexed: 12/11/2022] Open
Abstract
N-Formyl-methionyl-leucyl-phenylalanine (fMLP) and platelet-activating factor (PAF) induce similar intracellular signalling profiles; but only fMLP induces interleukin-8 (IL-8) release and nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase activity in neutrophils. Because the role of ROS on IL-8 release in neutrophils is until now controversial, we assessed if NADPH oxidase is involved in the IL-8 secretions and PI3K/Akt, MAPK, and NF-κB pathways activity induced by fMLP. Neutrophils were obtained from healthy volunteers. IL-8 was measured by ELISA, IL-8 mRNA by qPCR, and ROS production by luminol-amplified chemiluminescence, reduction of ferricytochrome c, and FACS. Intracellular pH changes were detected by spectrofluorescence. ERK1/2, p38 MAPK, and Akt phosphorylation were analysed by immunoblotting and NF-κB was analysed by immunocytochemistry. Hydroxy-3-methoxyaceto-phenone (HMAP), diphenyleneiodonium (DPI), and siRNA Nox2 reduced the ROS and IL-8 release in neutrophils treated with fMLP. HMAP, DPI, and amiloride (a Na+/H+ exchanger inhibitor) inhibited the Akt phosphorylation and did not affect the p38 MAPK and ERK1/2 activity. DPI and HMAP reduced NF-κB translocation induced by fMLP. We showed that IL-8 release induced by fMLP is dependent on NADPH oxidase, and ROS could play a redundant role in cell signalling, ultimately activating the PI3K/Akt and NF-κB pathways in neutrophils.
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8
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Li J, Kim K, Barazia A, Tseng A, Cho J. Platelet-neutrophil interactions under thromboinflammatory conditions. Cell Mol Life Sci 2015; 72:2627-43. [PMID: 25650236 DOI: 10.1007/s00018-015-1845-y] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Revised: 01/07/2015] [Accepted: 01/26/2015] [Indexed: 12/11/2022]
Abstract
Platelets primarily mediate hemostasis and thrombosis, whereas leukocytes are responsible for immune responses. Since platelets interact with leukocytes at the site of vascular injury, thrombosis and vascular inflammation are closely intertwined and occur consecutively. Recent studies using real-time imaging technology demonstrated that platelet-neutrophil interactions on the activated endothelium are an important determinant of microvascular occlusion during thromboinflammatory disease in which inflammation is coupled to thrombosis. Although the major receptors and counter receptors have been identified, it remains poorly understood how heterotypic platelet-neutrophil interactions are regulated under disease conditions. This review discusses our current understanding of the regulatory mechanisms of platelet-neutrophil interactions in thromboinflammatory disease.
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Affiliation(s)
- Jing Li
- Department of Pharmacology, University of Illinois College of Medicine, 835 S. Wolcott Ave, E403, Chicago, IL, 60612, USA
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9
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Dumas E, Martel C, Neagoe PE, Bonnefoy A, Sirois MG. Angiopoietin-1 but not angiopoietin-2 promotes neutrophil viability: Role of interleukin-8 and platelet-activating factor. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:358-67. [DOI: 10.1016/j.bbamcr.2011.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 12/06/2011] [Accepted: 12/07/2011] [Indexed: 01/15/2023]
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10
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Higo T, Duronio V, Tudan C, Burt HM, Jackson JK. Calcium pyrophosphate dihydrate crystal-induced inhibition of neutrophil apoptosis: involvement of Bcl-2 family members. Inflamm Res 2009; 59:71-81. [PMID: 19669391 DOI: 10.1007/s00011-009-0073-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 05/26/2009] [Accepted: 07/21/2009] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION The inflammation associated with calcium pyrophosphate dihydrate (CPPD) crystal-induced arthritis arises from the activation of neutrophils with crystals in the synovial joint. Furthermore, constitutive neutrophil apoptosis is inhibited by this interaction with CPPD so that the lifetime of the cells and the duration of the inflammatory response are extended. The objective of this study was to investigate the role of bcl-2 protein family members in the CPPD-induced prosurvival response. METHODS Apoptosis was measured using DNA fragmentation and Caspase 3 assays. The expression and activation levels of the bcl-2 protein family members A1, Mcl-1, Bcl-xl, Bim, Bad and Bax-alpha were measured using western blot analysis. RESULTS The prosurvival proteins Mcl-1 and Bcl-xl were both found to be strongly expressed but unaffected by CPPD-induced neutrophil activation over 3 h. The expression of proapoptotic proteins Bim and Bax-alpha was found to decrease over the time course of a 3 h incubation of neutrophils with CPPD crystals (but not the bacterial chemoattractant fMLP). Furthermore, expression of the unphosphorylated (active, proapoptotic) form of Bim was dominant in control cells at 0.5 h, whereas the status of this protein switched to the phosphorylated form following cell activation by both CPPD and fMLP. For CPPD (but not fMLP) this phosphorylation effect reversed over a 3 h incubation. CONCLUSION Upon stimulation by CPPD crystals, the expression of both Bim and Bax-alpha decreased after 3 h suggesting a reduced proapoptotic effect of these proteins so that the static expression of the prosurvival proteins Bcl-xl and Mcl-1 might allow for a temporary shift in the balance to a prosurvival state of the cells. Because a sudden (but transient) increase in the phosphorylated form of Bim was observed in CPPD-stimulated neutrophils it is possible that this species might act as a signaling intermediate, resulting in the observed downregulation of Bax-alpha.
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Affiliation(s)
- Tobi Higo
- University of British Columbia, Vancouver, Canada
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11
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Lu J, Caplan MS, Li D, Jilling T. Polyunsaturated fatty acids block platelet-activating factor-induced phosphatidylinositol 3 kinase/Akt-mediated apoptosis in intestinal epithelial cells. Am J Physiol Gastrointest Liver Physiol 2008; 294:G1181-90. [PMID: 18356536 PMCID: PMC2692041 DOI: 10.1152/ajpgi.00343.2007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have shown earlier that platelet-activating factor (PAF) causes apoptosis in enterocytes via a mechanism that involves Bax translocation to mitochondria, followed by caspase activation and DNA fragmentation. Herein we report that, in rat small intestinal epithelial cells (IEC-6), these downstream apoptotic effects are mediated by a PAF-induced inhibition of the phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B (Akt) signaling pathway. Treatment with PAF results in rapid dephosphorylation of Akt, phosphoinositide-dependent kinase-1, and the YXXM p85 binding motif of several proteins and redistribution of Akt-pleckstrin homology domain-green fluorescent protein, i.e., an in vivo phosphatidylinositol (3,4,5)-trisphosphate sensor, from membrane to cytosol. The proapoptotic effects of PAF were inhibited by both n-3 and n-6 polyunsaturated fatty acids but not by a saturated fatty acid palmitate. Indomethacin, an inhibitor of prostaglandin biosynthesis, did not influence the baseline or PAF-induced apoptosis, but 2-bromopalmitate, an inhibitor of protein palmitoylation, inhibited all of the proapoptotic effects of PAF. Our data strongly suggest that an inhibition of the PI 3-kinase/Akt signaling pathway is the main mechanism of PAF-induced apoptosis in enterocytes and that polyunsaturated fatty acids block this mechanism very early in the signaling cascade independently of any effect on prostaglandin synthesis, and probably directly via an effect on protein palmitoylation.
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Affiliation(s)
- Jing Lu
- Evanston Northwestern Healthcare Research Institute, Evanston,Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinios
| | - Michael S. Caplan
- Evanston Northwestern Healthcare Research Institute, Evanston,Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinios
| | - Dan Li
- Evanston Northwestern Healthcare Research Institute, Evanston
| | - Tamas Jilling
- Evanston Northwestern Healthcare Research Institute, Evanston,Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinios
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12
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Zhao L, Wang Y, Sun N, Liu X, Li L, Shi J. Electroacupuncture regulates TRPM7 expression through the trkA/PI3K pathway after cerebral ischemia-reperfusion in rats. Life Sci 2007; 81:1211-22. [PMID: 17904584 DOI: 10.1016/j.lfs.2007.08.034] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 08/23/2007] [Accepted: 08/27/2007] [Indexed: 10/22/2022]
Abstract
Recently, it was demonstrated that TRPM7 is an essential mediator of anoxia-induced neuronal death. Meanwhile, nerve growth factor (NGF) is known to have survival and neuroprotective effects by interacting with the high affinity neurotrophin receptor, tropomyosin-related kinase A (trkA). In the present study, we found that electroacupuncture (EA) treatment could up-regulate trkA expression after focal cerebral ischemia in rats. At the same time, EA therapy obviously decreased the high expression of TRPM7 induced by ischemia. Using K252a to inhibit trkA, we found that the EA-mediated down-regulation of TRPM7 was significantly suppressed in rats subjected to cerebral ischemia. TrkA can utilize two distinct signaling pathways: the phosphatidylinositol 3-kinase (PI3K) pathway and the extracellular signal-related kinase (ERK) pathway. We found that the effect of EA on TRPM7 was also inhibited by a PI3K inhibitor, while an ERK inhibitor had no effect. Taken together, our findings suggest that EA can reverse the ischemia-induced increase of TRPM7 levels through the trkA-PI3K pathway.
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Affiliation(s)
- Li Zhao
- Department of Neurobiology, Key Laboratory of Neurological Disease of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, PR China
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13
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Zennadi R, Moeller BJ, Whalen EJ, Batchvarova M, Xu K, Shan S, Delahunty M, Dewhirst MW, Telen MJ. Epinephrine-induced activation of LW-mediated sickle cell adhesion and vaso-occlusion in vivo. Blood 2007; 110:2708-17. [PMID: 17609430 PMCID: PMC1988948 DOI: 10.1182/blood-2006-11-056101] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sickle red cell (SS RBC) adhesion is believed to contribute to the process of vaso-occlusion in sickle cell disease (SCD). We previously found that the LW RBC adhesion receptor can be activated by epinephrine to mediate SS RBC adhesion to endothelial alphavbeta3 integrin. To determine the contribution of LW activation to vaso-occlusive events in vivo, we investigated whether in vitro treatment of SS RBCs by epinephrine resulted in vaso-occlusion in intact microvasculature after RBC infusion into nude mice. Epinephrine enhanced human SS but not normal RBC adhesion to murine endothelial cells in vitro and to endothelium in vivo, promoting vaso-occlusion and RBC organ sequestration. Murine sickle RBCs also responded to epinephrine with increased adhesion to postcapillary endothelium in nude mice. Epinephrine-induced SS RBC adhesion, vaso-occlusion, and RBC organ trapping could be prevented by the beta-adrenergic receptor (beta-AR) antagonist, propranolol. Infusion of soluble recombinant LW also significantly reduced adhesion and vaso-occlusion. In addition, epinephrine-treated SS RBCs induced activation of murine leukocyte adhesion to endothelium as well. We conclude that LW activation by epinephrine via beta-AR stimulation can promote both SS RBC and leukocyte adhesion as well as vaso-occlusion, suggesting that both epinephrine and LW play potentially pathophysiological roles in SCD.
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Affiliation(s)
- Rahima Zennadi
- Division of Hematology and Duke Comprehensive Sickle Cell Center, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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14
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Miller-Kittrell M, Sai J, Penfold M, Richmond A, Sparer TE. Functional characterization of chimpanzee cytomegalovirus chemokine, vCXCL-1(CCMV). Virology 2007; 364:454-65. [PMID: 17433398 PMCID: PMC2665277 DOI: 10.1016/j.virol.2007.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 03/05/2007] [Indexed: 11/27/2022]
Abstract
Human cytomegaloviruses (HCMVs) are important pathogens in immunocompromised patients and newborns. The viral chemokine, vCXCL-1, of the Toledo (Tol) strain of HCMV has been implicated in HCMV virulence. Chimpanzee CMV (CCMV) has several genes with similarity to the vCXCL-1(Tol) gene, UL146. In order to test whether the CCMV viral chemokine, vCXCL-1(CCMV), is similar to vCXCL-1(Tol), we characterized its function in vitro. Receptor binding, activation, chemotaxis, signaling, and apoptosis in neutrophils were compared between vCXCL-1(Tol) and vCXCL-1(CCMV) and host chemokines. Although the homologues had similar activation potentials, chemotactic properties, and signaling, vCXCL-1(CCMV) had a approximately 70-fold lower affinity for CXCR2 and displayed differences in integrin upregulation and neutrophil apoptosis. These data demonstrate that in spite of extensive amino acid variability in vCXCL-1, CCMV may provide a model for assessing the role of vCXCL-1 in CMV pathogenesis in vivo.
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Affiliation(s)
- Mindy Miller-Kittrell
- Department of Microbiology, University of Tennessee, Walters Life Sciences Rm. F417, Knoxville, TN 37996, USA
| | - Jiqing Sai
- Department of Veteran Affairs, Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | | | - Ann Richmond
- Department of Veteran Affairs, Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Tim E. Sparer
- Department of Microbiology, University of Tennessee, Walters Life Sciences Rm. F417, Knoxville, TN 37996, USA
- Corresponding author. Fax: +1 865 974 4007. E-mail address: (T.E. Sparer)
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15
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Baskin-Bey ES, Washburn K, Feng S, Oltersdorf T, Shapiro D, Huyghe M, Burgart L, Garrity-Park M, van Vilsteren FGI, Oliver LK, Rosen CB, Gores GJ. Clinical Trial of the Pan-Caspase Inhibitor, IDN-6556, in Human Liver Preservation Injury. Am J Transplant 2007; 7:218-25. [PMID: 17227570 DOI: 10.1111/j.1600-6143.2006.01595.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cold ischemia/warm reperfusion (CI/WR) injury remains a problem in liver transplantation. The aim of the current study was to assess the utility of the pan-caspase inhibitor IDN-6556 on CI/WR injury during human liver transplantation. This report is a post hoc analysis of a Phase II, multi-center, randomized, placebo-controlled, double-blinded, parallel group study. Subjects were assigned to four treatment groups: Group 1 (Organ storage/flush: Placebo-Recipient: Placebo); Group 2 (Organ storage/flush: 15 microg/mL-Recipient: Placebo); Group 3 (Organ storage/flush: 5 microg/mL-Recipient: 0.5 mg/kg); and Group 4 (Organ storage/flush: 15 microg/mL-Recipient: 0.5 mg/kg). Liver cell apoptosis was assessed by serum concentrations of the apoptosis-associated CK18Asp396 ('M30') neo-epitope, TUNEL assay and caspase 3/7 immunohistochemistry. Liver injury was assessed by serum AST/ALT determinations. Serum markers of liver cell apoptosis were reduced in all groups receiving drug as compared to placebo. However, TUNEL, caspase 3/7 positive cells and serum AST/ALT levels were only consistently reduced in Group 2 (drug exposed to organ only). This reduction in serum transaminases was significant and observed across the study. In conclusion, IDN-6556 when administered in cold storage and flush solutions during liver transplantation offers local therapeutic protection against CI/WR-mediated apoptosis and injury. However, larger studies are required to confirm these observations.
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Affiliation(s)
- E S Baskin-Bey
- William J. von Liebig Transplant Center, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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16
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Moreno SE, Alves-Filho JC, Rios-Santos F, Silva JS, Ferreira SH, Cunha FQ, Teixeira MM. Signaling via platelet-activating factor receptors accounts for the impairment of neutrophil migration in polymicrobial sepsis. THE JOURNAL OF IMMUNOLOGY 2006; 177:1264-71. [PMID: 16818786 DOI: 10.4049/jimmunol.177.2.1264] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Sepsis is a systemic inflammatory response that results from the inability of the immune system to limit bacterial spread during an ongoing infection. Recently, we have documented an impaired neutrophil migration toward the infectious focus in severe sepsis. This impairment seems to be mediated by circulating cytokines, chemokines, and NO. Platelet-activating factor (PAF) plays an important role in the orchestration of different inflammatory reactions, including the release of cytokines, chemokines, and free radicals. Using a PAFR antagonist, PCA-4248, and PAFR-deficient mice, we investigated whether signaling via PAFR was relevant for the failure of neutrophils to migrate to the site of infection after lethal sepsis caused by cecum ligation and puncture in mice. In PAFR-deficient mice or mice pretreated with PCA-4248 (5 mg/kg) and subjected to lethal sepsis, neutrophil migration failure was prevented, and bacterial clearance was more efficient. There was also reduced systemic inflammation (low serum cytokine levels), lower nitrate levels in plasma, and higher survival rate. Altogether, the results firmly establish a role for PAFR in mediating the early impairment of neutrophil migration toward the infectious focus. Blockade of PAFR may prevent the establishment of severe sepsis.
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Affiliation(s)
- Susana E Moreno
- Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
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17
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Heon Seo K, Ko HM, Kim HA, Choi JH, Jun Park S, Kim KJ, Lee HK, Im SY. Platelet-activating factor induces up-regulation of antiapoptotic factors in a melanoma cell line through nuclear factor-kappaB activation. Cancer Res 2006; 66:4681-6. [PMID: 16651419 DOI: 10.1158/0008-5472.can-05-3186] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, we investigated the influence of platelet-activating factor (PAF) on the induction of apoptosis-regulating factors in B16F10 melanoma cells. PAF increased the expression of mRNA and the protein synthesis of antiapoptotic factors, such as Bcl-2 and Bcl-xL, but did not increase the expression of the proapoptotic factor, Bax. A selective nuclear factor-kappaB (NF-kappaB) inhibitor, parthenolide, inhibited the effects of PAF. Furthermore, PAF inhibited etoposide-induced increases in caspase-3, caspase-8, and caspase-9 activities, as well as cell death. p50/p65 heterodimer increased the mRNA expression of Bcl-2 and Bcl-xL and decreased etoposide-induced caspase activities and cell death. In an in vivo model in which Matrigel was injected s.c., PAF augmented the growth of B16F10 cells and attenuated etoposide-induced inhibition of B16F10 cells growth. These data indicate that PAF induces up-regulation of antiapoptotic factors in a NF-kappaB-dependent manner in a melanoma cell line, therefore suggesting that PAF may diminish the cytotoxic effect of chemotherapeutic agents.
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Affiliation(s)
- Kook Heon Seo
- Department of Biological Sciences, The Institute of Basic Sciences, Chonnam National University, Kwangju, Republic of Korea
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18
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Cowburn AS, Sobolewski A, Reed BJ, Deighton J, Murray J, Cadwallader KA, Bradley JR, Chilvers ER. Aminopeptidase N (CD13) Regulates Tumor Necrosis Factor-α-induced Apoptosis in Human Neutrophils. J Biol Chem 2006; 281:12458-67. [PMID: 16533817 DOI: 10.1074/jbc.m511277200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neutrophil apoptosis plays a central role in the resolution of granulocytic inflammation. We have shown previously that tumor necrosis factor-alpha (TNFalpha) enhances the rate of neutrophil apoptosis at early time points via a mechanism involving both TNF receptor (TNFR) I and TNFRII. Here we reveal a marked but consistent variation in the magnitude of the pro-apoptotic effect of TNFalpha in neutrophils isolated from healthy donors, and we show that inhibition of cell surface aminopeptidase N (APN) using actinonin, bestatin, or inhibitory peptides significantly enhanced the efficacy of TNFalpha-induced killing. Notably, an inverse correlation is shown to exist between neutrophil APN activity and the sensitivity of donor cells to TNFalpha-induced apoptosis. Inhibition of cell surface APN appears to interfere with the shedding of TNFRI, and as a consequence results in augmented TNFalpha-induced apoptosis, cell polarization, and TNFalpha-primed, formyl-methionyl-leucyl-phenylalanine-stimulated respiratory burst. Of note, actinonin and bestatin had no effect on TNFRII expression under resting or TNFalpha-stimulated conditions and did not alter CXCRI or CXCRII expression. These data suggest significant variation in the activity of APN/CD13 on the cell surface of neutrophils in normal individuals and reveal a novel mechanism whereby APN/CD13 regulates TNFalpha-induced apoptosis via inhibition of TNFRI shedding. This has therapeutic relevance for driving neutrophil apoptosis in vivo.
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Affiliation(s)
- Andrew S Cowburn
- Respiratory Medicine Division, Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge CB2 2QQ, United Kingdom.
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19
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Sawatzky DA, Willoughby DA, Colville-Nash PR, Rossi AG. The involvement of the apoptosis-modulating proteins ERK 1/2, Bcl-xL and Bax in the resolution of acute inflammation in vivo. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:33-41. [PMID: 16400007 PMCID: PMC1592663 DOI: 10.2353/ajpath.2006.050058] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Inflammatory cell recruitment, activation, and apoptosis are highly regulated processes involving several checkpoints controlling the resolution of inflammation. We investigated the role of the mitogen-activated protein kinase (MAPK) signaling pathway (ie, ERK1/2) and apoptosis-regulating Bcl-2 family members (ie, Bcl-x(L) and Bax) in the resolution of a rat carrageenan-induced pleurisy model. The specific ERK1/2 inhibitor PD98059 enhanced the resolution of inflammation, whereas the MEK1/2 inhibitor U0126 had no effect and the flavonoid apigenin, a nonspecific inhibitor of ERK1/2 and COX-2, augmented inflammation. Specifically, PD98059 significantly decreased the total number of macrophages and neutrophils in the pleural cavity, mainly by increasing the rate of neutrophil apoptosis, as measured by Annexin V labeling and morphological analysis. Conversely, a specific inhibitor of proapoptotic Bax (V5) increased inflammation, indicating that by preventing apoptosis in vivo, resolution of inflammation is delayed. This was associated with a decrease in neutrophil apoptosis and an increase in macrophage and neutrophil numbers perpetuating the inflammatory response. In conclusion, this study shows that ERK1/2, Bax, and Bcl-x(L) play important functional roles in the resolution phase of the acute inflammatory response in vivo by influencing apoptosis. Importantly, these data may provide novel therapeutic targets for the treatment of inflammatory diseases.
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Affiliation(s)
- Deborah A Sawatzky
- MRC Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh Medical School, 47 Little France Crescent, Edinburgh, Scotland, UK EH16 4TJ.
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20
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Abstract
Platelet-activating factor (PAF) is a potent proinflammatory phospholipid mediator that belongs to a family of biologically active, structurally related alkyl phosphoglycerides with diverse pathological and physiological effects. This bioactive phospholipid mediates processes as diverse as wound healing, physiological inflammation, angiogenesis, apoptosis, reproduction and long-term potentiation. PAF acts by binding to a specific G protein-coupled receptor to activate multiple intracellular signaling pathways. Since most cells both synthesize and release PAF and express PAF receptors, PAF has potent biological actions in a broad range of cell types and tissues. Inappropriate activation of this signaling pathway is associated with many diseases in which inflammation is thought to be one of the underlying features. Acute pancreatitis (AP) is a common inflammatory disease. The onset of AP is pancreatic autodigestion mediated by abnormal activation of pancreatic enzyme caused by multiple agents, which subsequently induce pancreatic and systemic inflammatory reactions. A number of experimental pancreatitis and clinical trials indicate that PAF does play a critical role in the pathogenesis of AP. Administration of PAF receptor antagonist can significantly reduce local and systemic events that occur in AP. This review focuses on the aspects that are more relevant to the pathogenesis of AP.
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Affiliation(s)
- Li-Rong Liu
- Department of Gastroenterology, Pancreas Center, Affiliated Hospital of Medical College of the Chinese People's Armed Police Forces, Chenglinzhuang Road, Tianjin 300162, China
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21
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Choi KS, Park JT, Dumler JS. Anaplasma phagocytophilum delay of neutrophil apoptosis through the p38 mitogen-activated protein kinase signal pathway. Infect Immun 2006; 73:8209-18. [PMID: 16299317 PMCID: PMC1307085 DOI: 10.1128/iai.73.12.8209-8218.2005] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Human granulocytic anaplasmosis is caused by the obligate intracellular bacterium Anaplasma phagocytophilum. The bacterium avoids host innate defenses in part by infecting, surviving in, and propagating in neutrophils, as well as by inhibiting neutrophil apoptosis. However, the mechanisms of A. phagocytophilum survival in neutrophils and the inhibition of spontaneous apoptosis are not well understood. In this study, we demonstrated that antiapoptotic Mcl-1 protein (Bcl-2 family) expression is maintained and that inhibition of procaspase-3 processing occurs in A. phagocytophilum-infected human neutrophils. An evaluation of p38 mitogen-activated protein kinase (MAPK) showed evidence of increased phosphorylation with infection. Moreover, antagonism of p38 MAPK by the inhibitor SB203580 reversed apoptosis inhibition in live or heat-killed A. phagocytophilum-infected neutrophils. A role for the autocrine or paracrine production of antiapoptotic interleukin 8 (IL-8) expressed with A. phagocytophilum infection was excluded by the use of IL-8-, IL-8R1 (CXCR1)-, and IL-8R2 (CXCR2)-blocking antibodies. As previously demonstrated, the antiapoptotic effect was initially mediated by exposure to A. phagocytophilum components in heat-killed bacteria. However, an important role for active infection is demonstrated by the additional delay in apoptosis with intracellular growth and the refractory abrogation of this response by the p38 MAPK inhibitor 3 to 6 h after neutrophil infection. These results suggest that the initial activation of the p38 MAPK pathway leading to A. phagocytophilum-delayed neutrophil apoptosis is bypassed with active intracellular infection. Moreover, active intracellular infection contributes more to the overall delay in apoptosis than do components of heat-killed A. phagocytophilum alone.
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Affiliation(s)
- Kyoung-Seong Choi
- Division of Medical Microbiology, Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 624, Baltimore, MD 21205, USA.
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22
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Hidalgo MA, Romero A, Figueroa J, Cortés P, Concha II, Hancke JL, Burgos RA. Andrographolide interferes with binding of nuclear factor-kappaB to DNA in HL-60-derived neutrophilic cells. Br J Pharmacol 2005; 144:680-6. [PMID: 15678086 PMCID: PMC1576048 DOI: 10.1038/sj.bjp.0706105] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
1. Andrographolide, the major active component from Andrographis paniculata, has shown to possess anti-inflammatory activity. Andrographolide inhibits the expression of several proinflammatory proteins that exhibit a nuclear factor kappa B (NF-kappaB) binding site in their gene. 2. In the present study, we analyzed the effect of andrographolide on the activation of NF-kappaB induced by platelet-activating factor (PAF) and N-formyl-methionyl-leucyl-phenylalanine (fMLP) in HL-60 cells differentiated to neutrophils. 3. PAF (100 nM) and fMLP (100 nM) induced activation of NF-kappaB as determined by degradation of inhibitory factor B alpha (IkappaB alpha) using Western blotting in cytosolic extracts and by binding to DNA using electrophoretic mobility shift assay (EMSA) in nuclear extracts. 4. Andrographolide (5 and 50 microM) inhibited the NF-kappaB-luciferase activity induced by PAF. However, andrographolide did not reduce phosphorylation of p38 MAPK or ERK1/2 and did not change IkappaB alpha degradation induced by PAF and fMLP. 5. Andrographolide reduced the DNA binding of NF-kappaB in whole cells and in nuclear extracts induced by PAF and fMLP. 6. Andrographolide reduced cyclooxygenase-2 (COX-2) expression induced by PAF and fMLP in HL-60/neutrophils. 7. It is concluded that andrographolide exerts its anti-inflammatory effects by inhibiting NF-kappaB binding to DNA, and thus reducing the expression of proinflammatory proteins, such as COX-2.
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Affiliation(s)
- María A Hidalgo
- Laboratory of Molecular Pharmacology, Institute of Pharmacology, Universidad Austral de Chile, PO Box 567, Isla Teja s/n, Valdivia, Chile
- Institute of Biochemistry, Universidad Austral de Chile, Valdivia, Chile
| | - Alex Romero
- Institute of Biochemistry, Universidad Austral de Chile, Valdivia, Chile
| | - Jaime Figueroa
- Institute of Biochemistry, Universidad Austral de Chile, Valdivia, Chile
| | - Patricia Cortés
- Immunobiology Center, Mount Sinai School of Medicine, New York, U.S.A
| | - Ilona I Concha
- Institute of Biochemistry, Universidad Austral de Chile, Valdivia, Chile
| | - Juan L Hancke
- Laboratory of Molecular Pharmacology, Institute of Pharmacology, Universidad Austral de Chile, PO Box 567, Isla Teja s/n, Valdivia, Chile
| | - Rafael A Burgos
- Laboratory of Molecular Pharmacology, Institute of Pharmacology, Universidad Austral de Chile, PO Box 567, Isla Teja s/n, Valdivia, Chile
- Author for correspondence:
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