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Leder EH, André C, Le Moan A, Töpel M, Blomberg A, Havenhand JN, Lindström K, Volckaert FAM, Kvarnemo C, Johannesson K, Svensson O. Post-glacial establishment of locally adapted fish populations over a steep salinity gradient. J Evol Biol 2020; 34:138-156. [PMID: 32573797 DOI: 10.1111/jeb.13668] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 06/04/2020] [Indexed: 12/21/2022]
Abstract
Studies of colonization of new habitats that appear from rapidly changing environments are interesting and highly relevant to our understanding of divergence and speciation. Here, we analyse phenotypic and genetic variation involved in the successful establishment of a marine fish (sand goby, Pomatoschistus minutus) over a steep salinity drop from 35 PSU in the North Sea (NE Atlantic) to two PSU in the inner parts of the post-glacial Baltic Sea. We first show that populations are adapted to local salinity in a key reproductive trait, the proportion of motile sperm. Thereafter, we show that genome variation at 22,190 single nucleotide polymorphisms (SNPs) shows strong differentiation among populations along the gradient. Sequences containing outlier SNPs and transcriptome sequences, mapped to a draft genome, reveal associations with genes with relevant functions for adaptation in this environment but without overall evidence of functional enrichment. The many contigs involved suggest polygenic differentiation. We trace the origin of this differentiation using demographic modelling and find the most likely scenario is that at least part of the genetic differentiation is older than the Baltic Sea and is a result of isolation of two lineages prior to the current contact over the North Sea-Baltic Sea transition zone.
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Affiliation(s)
- Erica H Leder
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Biology, University of Turku, Turku, Finland.,Natural History Museum, University of Oslo, Oslo, Norway
| | - Carl André
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Alan Le Moan
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Mats Töpel
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Anders Blomberg
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Jonathan N Havenhand
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Kai Lindström
- Environmental and Marine Biology, Åbo Akademi University, Turku, Finland
| | - Filip A M Volckaert
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, Leuven, Belgium
| | - Charlotta Kvarnemo
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Kerstin Johannesson
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Ola Svensson
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden.,Department for Pre-School and School Teacher Education, University of Borås, Borås, Sweden
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Qian X, Zhao H, Chen X, Li J. Disruption of transient receptor potential melastatin 2 decreases elastase release and bacterial clearance in neutrophils. Innate Immun 2019; 24:122-130. [PMID: 29495939 PMCID: PMC6830898 DOI: 10.1177/1753425918759181] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Elastase released by neutrophils is critical for eliminating Gram-negative
bacteria. Ca2+ influx plays a key role in elastase release and
bacterial clearance in neutrophils. Transient receptor potential melastatin 2
(TRPM2) is a Ca2+-permeable cation channel highly expressed in
neutrophils. Here, we explore the role and possible mechanism of TRPM2 in
bacterial clearance in TRPM2 knockout (TRPM2-KO) mice neutrophils. After
exposure to Escherichia coli, TRPM2–KO bone marrow
neutrophils (BMNs) had increased bacterial burden and decreased elastase
release. The same was observed for septic TRPM2-KO mice which also had decreased
survival rate. After stimulation with chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLP), elastase release
was lower in TRPM2-KO BMNs than in wild type (WT) BMNs. Pre-treatment of WT BMNs
with p38 MAPK inhibitor reduced fMLP-induced elastase release. Compared with WT
BMNs, TRPM2-KO BMNs had decreased p38 MAPK phosphorylation after fMLP
stimulation. Removal of extracellular Ca2+ reduced fMLP-induced p38
MAPK phosphorylation and elastase release. The concentration of intracellular
Ca2+ decreased in TRPM2-KO BMNs compared with WT BMNs after fMLP
treatment. Hence, TRPM2 plays an important role in bacterial clearance in
neutrophils, possibly by regulating elastase release. TRPM2-mediated
Ca2+ influx regulates elastase release partially via p38 MAPK
phosphorylation in neutrophils.
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Affiliation(s)
- XiaoWei Qian
- 1 Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, China.,2 Department of Anesthesiology, Critical Care and Pain Medicine, The Second Affiliated Hospital and Yuying Children Hospital of Wenzhou Medical University, China
| | - Hang Zhao
- 3 Department of Anesthesiology, Yancheng Third People's Hospital, China
| | - XinZhong Chen
- 1 Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, China
| | - Jun Li
- 2 Department of Anesthesiology, Critical Care and Pain Medicine, The Second Affiliated Hospital and Yuying Children Hospital of Wenzhou Medical University, China
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3
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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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The beta-2-adrenoreceptor agonists, formoterol and indacaterol, but not salbutamol, effectively suppress the reactivity of human neutrophils in vitro. Mediators Inflamm 2014; 2014:105420. [PMID: 24733958 PMCID: PMC3964838 DOI: 10.1155/2014/105420] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/15/2014] [Accepted: 01/29/2014] [Indexed: 12/11/2022] Open
Abstract
The clinical relevance of the anti-inflammatory properties of beta-2 agonists remains contentious possibly due to differences in their molecular structures and agonist activities. The current study has compared the effects of 3 different categories of β2-agonists, namely, salbutamol (short-acting), formoterol (long-acting) and indacaterol (ultra-long-acting), at concentrations of 1–1000 nM, with human blood neutrophils in vitro. Neutrophils were activated with either N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP, 1 µM) or platelet-activating factor (PAF, 200 nM) in the absence and presence of the β2-agonists followed by measurement of the generation of reactive oxygen species and leukotriene B4, release of elastase, and expression of the β2-integrin, CR3, using a combination of chemiluminescence, ELISA, colorimetric, and flow cytometric procedures respectively. These were correlated with alterations in the concentrations of intracellular cyclic-AMP and cytosolic Ca2+. At the concentrations tested, formoterol and indacaterol caused equivalent, significant (P < 0.05 at 1–10 nM) dose-related inhibition of all of the pro-inflammatory activities tested, while salbutamol was much less effective (P < 0.05 at 100 nM and higher). Suppression of neutrophil reactivity was accompanied by elevations in intracellular cAMP and accelerated clearance of Ca2+ from the cytosol of activated neutrophils. These findings demonstrate that β2-agonists vary with respect to their suppressive effects on activated neutrophils.
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Liz R, Zanatta L, dos Reis GO, Horst H, Pizzolatti MG, Silva FRMB, Fröde TS. Acute effect of β-sitosterol on calcium uptake mediates anti-inflammatory effect in murine activated neutrophils. J Pharm Pharmacol 2012; 65:115-22. [PMID: 23215694 DOI: 10.1111/j.2042-7158.2012.01568.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVES To evaluate the effect of β-sitosterol on ⁴⁵Ca²⁺ uptake in activated murine neutrophils, and upon myeloperoxidase and adenosine deaminase activity, and interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α) levels, in carrageenan-induced inflammation in the mouse air pouch model. METHODS Dried Esenbeckia leiocarpa bark was macerated and extracted resulting in a crude hydroalcoholic extract (CHE) that was partitioned to obtain an alkaloid fraction. The alkaloid was then partitioned in polar and nonpolar subfractions. β-Sitosterol was isolated from the nonpolar subfraction and identified by comparison with the literature. The effect of β-sitosterol on ⁴⁵Ca²⁺ uptake in activated murine neutrophils, and upon myeloperoxidase and adenosine deaminase activity, IL-1β and TNF-α levels in carrageenan-induced inflammation in mice were evaluated. KEY FINDINGS β-Sitosterol promoted a time- and dose-dependent increase of the calcium uptake in activated neutrophils that was promptly reversed by nifedipine, BAPTA-AM, LY294002, and colchicine. β-Sitosterol inhibited myeloperoxidase and adenosine deaminase activity, and IL-1β and TNF-α levels. CONCLUSIONS β-Sitosterol inhibited either myeloperoxidase and adenosine deaminase activity or IL-1β and TNF-α levels. This effect seemed to be mediated by the calcium uptake in activated neutrophils in a time- and concentration-dependent manner through L-type voltage dependent calcium channels, intracellular calcium, phosphoinositide kinase-3, and microtubule modulation.
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Affiliation(s)
- Rafael Liz
- Department of Clinical Analysis, Centre of Health Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
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6
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Pantaler E, Lückhoff A. Inhibitors of TRP channels reveal stimulus-dependent differential activation of Ca2+ influx pathways in human neutrophil granulocytes. Naunyn Schmiedebergs Arch Pharmacol 2009; 380:497-507. [PMID: 19894037 DOI: 10.1007/s00210-009-0464-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 10/05/2009] [Indexed: 11/28/2022]
Abstract
A pharmacological characterization of Ca(2+) influx pathways in neutrophil granulocytes is problematic because of the lack of specific inhibitors. The activation of transient receptor potential cation channel, subfamily M, member 2 (TRPM2) channels by intracellular adenosine diphosphate ribose (ADPR), well characterized in neutrophils, is reportedly inhibited by 8-bromo-ADPR (8Br-ADPR). TRPM2 is blocked by N-(p-amylcinnamoyl)anthranilic acid (ACA) interfering with the pore, but ACA is as well effective on other transient receptor potential channels, especially transient receptor potential canonical (TRPC) channels. We wished to analyze whether ACA and 8Br-ADPR were suitable probes to demonstrate that different Ca(2+) entry pathways are activated in human neutrophil granulocytes by the receptor-dependent stimuli N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP) and platelet-activating factor (PAF) and the receptor-independent thapsigargin. Ca(2+)-influx-related increases in [Ca(2+)](i) were calculated by comparing aliquots of fluo-3-loaded neutrophils in the presence and absence of extracellular Ca(2+). Moreover, Mn(2+) quenching was used in fura-2-loaded cells. We compared 8Br-ADPR with ACA. 8Br-ADPR was exclusively effective when Ca(2+) influx (or Mn(2+) quenching) was induced by fMLP; it did not affect influx when PAF or thapsigargin was the stimulus. ACA inhibited Ca(2+) influx significantly more strongly when this was induced by PAF than by fMLP. Moreover, it reduced thapsigargin-induced Ca(2+) influx. The contribution of TRPM2 to Ca(2+) influx in neutrophils strongly depends on the stimulus; it is sizeable in the case of fMLP and minimal in the case of PAF. PAF induces Ca(2+) entry pathways different from TRPM2; the inhibition by ACA suggests the contribution of channels of the TRPC family.
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Affiliation(s)
- Elena Pantaler
- Institut für Physiologie, Medizinische Fakultät der Reinisch-Westfälischen Technischen Hochschule, Pauwelsstrasse 30, Aachen, Germany
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7
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Tintinger GR, Theron AJ, Steel HC, Cockeran R, Pretorius L, Anderson R. Protein kinase C promotes restoration of calcium homeostasis to platelet activating factor-stimulated human neutrophils by inhibition of phospholipase C. JOURNAL OF INFLAMMATION-LONDON 2009; 6:29. [PMID: 19874629 PMCID: PMC2777896 DOI: 10.1186/1476-9255-6-29] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Accepted: 10/30/2009] [Indexed: 11/10/2022]
Abstract
BACKGROUND The role of protein kinase C (PKC) in regulating the activity of phospholipase C (PLC) in neutrophils activated with the chemoattractant, platelet-activating factor (PAF, 20 and 200 nM), was probed in the current study using the selective PKC inhibitors, GF10903X (0.5 - 1 muM) and staurosporine (400 nM). METHODS Alterations in cytosolic Ca2+, Ca2+ influx, inositol triphosphate (IP3), and leukotriene B4 production were measured using spectrofluorimetric, radiometric and competitive binding radioreceptor and immunoassay procedures, respectively. RESULTS Activation of the cells with PAF was accompanied by an abrupt increase in cytosolic Ca2+ followed by a gradual decline towards basal levels. Pretreatment of neutrophils with the PKC inhibitors significantly increased IP3 production with associated enhanced Ca2+ release from storage vesicles, prolongation of the peak cytosolic Ca2+ transients, delayed clearance and exaggerated reuptake of the cation, and markedly increased synthesis of LTB4. The alterations in Ca2+ fluxes observed with the PKC inhibitors were significantly attenuated by U73122, a PLC inhibitor, as well as by cyclic AMP-mediated upregulation of the Ca2+-resequestering endomembrane ATPase.Taken together, these observations are compatible with a mechanism whereby PKC negatively modulates the activity of PLC, with consequent suppression of IP3 production and down-regulation of Ca2+ mediated pro-inflammatory responses of PAF-activated neutrophils. CONCLUSION Although generally considered to initiate and/or amplify intracellular signalling cascades which activate and sustain the pro-inflammatory activities of neutrophils and other cell types, the findings of the current study have identified a potentially important physiological, anti-inflammatory function for PKC, at least in neutrophils.
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Affiliation(s)
- Gregory R Tintinger
- Department of Internal Medicine, Faculty of Health Sciences, University of Pretoria, South Africa.
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8
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Steel HC, Theron AJ, Tintinger GR, Anderson R. Posaconazole attenuates leukotriene B4 release and uptake of calcium by chemoattractant-activated human neutrophils: a potential strategy to control neutrophil-mediated inflammation. J Antimicrob Chemother 2009; 64:1008-12. [PMID: 19744985 DOI: 10.1093/jac/dkp329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES This study was designed to investigate the neutrophil-targeted anti-inflammatory potential of posaconazole (0.1-5 microM, equivalent to 0.7-3.9 mg/L) by measuring the effects of this agent on the release of leukotriene B(4) (LTB(4)) and store-operated uptake of Ca(2+) following stimulation of human neutrophils with platelet-activating factor (200 nM). METHODS LTB(4) release and uptake of Ca(2+) by the cells were measured using an enzyme immunoassay and fura-2/AM-based spectrofluorimetric procedures, respectively. RESULTS Treatment of neutrophils with posaconazole resulted in dose-related attenuation of PAF-activated release of LTB(4) and influx of Ca(2+), which attained statistical significance at 1 microM of the antimycotic. CONCLUSIONS Although primarily an antimycotic, posaconazole possesses secondary anti-inflammatory activities, which may contribute to the therapeutic efficacy of this agent in patients with sepsis.
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Affiliation(s)
- H C Steel
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria and Tshwane Academic Division of the National Health Laboratory Service, Pretoria, South Africa
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9
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Tintinger GR, Steel HC, Theron AJ, Anderson R. Pharmacological control of neutrophil-mediated inflammation: strategies targeting calcium handling by activated polymorphonuclear leukocytes. Drug Des Devel Ther 2009; 2:95-104. [PMID: 19920897 PMCID: PMC2761182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Unlike most other effector cells of the innate, as well as the adaptive immune systems, the neutrophil is a relatively undiscerning aggressor with scant regard for damage limitation. Although this highly combative, professional phagocyte has become increasingly implicated in the immunopathogenesis of many acute and chronic inflammatory disorders, of both infective and noninfective origin, effective pharmacological strategies to counter neutrophil aggression have remained elusive. Activation of neutrophils results in rapid mobilization of both stored and extracellular Ca(2+), resulting in abrupt, usually transient increases in cytosolic Ca(2+), which precede, and are a prerequisite for activation of the Ca(2+)-dependent pro-inflammatory activities of these cells. Mobilization of Ca(2+) by, and restoration of Ca(2+) homeostasis to activated neutrophils are multistep processes which present a number of potential targets, some well recognized and others novel and unconventional, for the pharmacological control of neutrophil-mediated inflammation. Uncovering these targets represents the primary focus of this review.
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Affiliation(s)
- Gregory R Tintinger
- Correspondence: Gregory R Tintinger, Department of Immunology, PO Box 2034, Pretoria 0001, South Africa, Tel + 27 12 354 6883, Fax + 27 12 323 0732, Email
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Anderson R, Theron AJ, Gravett CM, Steel HC, Tintinger GR, Feldman C. Montelukast inhibits neutrophil pro-inflammatory activity by a cyclic AMP-dependent mechanism. Br J Pharmacol 2008; 156:105-15. [PMID: 19068077 DOI: 10.1111/j.1476-5381.2008.00012.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE The objective of this study was to characterize the effects of the cysteinyl leukotriene receptor antagonist, montelukast (0.1-2 micromol x L(-1)), on Ca(2+)-dependent pro-inflammatory activities, cytosolic Ca(2+) fluxes and intracellular cAMP in isolated human neutrophils activated with the chemoattractants, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (1 micromol x L(-1)) and platelet-activating factor (200 nmol x L(-1)). EXPERIMENTAL APPROACH Generation of reactive oxygen species was measured by lucigenin- and luminol-enhanced chemiluminescence, elastase release by a colourimetric assay, leukotriene B(4) and cAMP by competitive binding ELISA procedures, and Ca(2+) fluxes by fura-2/AM-based spectrofluorimetric and radiometric ((45)Ca(2+)) procedures. KEY RESULTS Pre-incubation of neutrophils with montelukast resulted in dose-related inhibition of the generation of reactive oxygen species and leukotriene B(4) by chemoattractant-activated neutrophils, as well as release of elastase, all of which were maximal at 2 micromol x L(-1) (mean percentages of the control values of 30 +/- 1, 12 +/- 3 and 21 +/- 3 respectively; P < 0.05). From a mechanistic perspective, treatment of chemoattractant-activated neutrophils with montelukast resulted in significant reductions in both post-peak cytosolic Ca(2+) concentrations and store-operated Ca(2+) influx. These montelukast-mediated alterations in Ca(2+) handling by the cells were associated with a significant elevation in basal cAMP levels, which resulted from inhibition of cyclic nucleotide phosphodiesterases. CONCLUSIONS AND IMPLICATIONS Montelukast, primarily a cysteinyl leukotriene (CysLT(1)) receptor antagonist, exhibited previously undocumented, secondary, neutrophil-directed anti-inflammatory properties, which appeared to be cAMP-dependent.
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Affiliation(s)
- Ronald Anderson
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
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Steel HC, Tintinger GR, Anderson R. Comparison of the Anti-inflammatory Activities of Imidazole Antimycotics in Relation to Molecular Structure. Chem Biol Drug Des 2008; 72:225-8. [DOI: 10.1111/j.1747-0285.2008.00694.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Bréchard S, Tschirhart EJ. Regulation of superoxide production in neutrophils: role of calcium influx. J Leukoc Biol 2008; 84:1223-37. [PMID: 18519744 PMCID: PMC2567897 DOI: 10.1189/jlb.0807553] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Upon stimulation, activation of NADPH oxidase complexes in neutrophils produces a burst of superoxide anions contributing to oxidative stress and the development of inflammatory process. Store-operated calcium entry (SOCE), whereby the depletion of intracellular stores induces extracellular calcium influx, is known to be a crucial element of NADPH oxidase regulation. However, the mechanistic basis mediating SOCE is still only partially understood, as is the signal-coupling pathway leading to modulation of store-operated channels. This review emphasizes the role of calcium influx in the control of the NADPH oxidase and summarizes the current knowledge of pathways mediating this extracellular calcium entry in neutrophils. Such investigations into the cross-talk between NADPH oxidase and calcium might allow the identification of novel pharmacological targets with clinical use, particularly in inflammatory diseases.
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Affiliation(s)
- Sabrina Bréchard
- Life Sciences Research Unit, University of Luxembourg, Luxembourg.
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13
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Steel HC, Tintinger GR, Theron AJ, Anderson R. Itraconazole-mediated inhibition of calcium entry into platelet-activating factor-stimulated human neutrophils is due to interference with production of leukotriene B4. Clin Exp Immunol 2007; 150:144-50. [PMID: 17683509 PMCID: PMC2219290 DOI: 10.1111/j.1365-2249.2007.03470.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The primary objective of this study was to probe the involvement of leukotriene B(4) (LTB(4)) in itraconazole (0.1-5 microM)-mediated inhibition of Ca(2+) uptake by chemoattractant-activated human neutrophils. Following exposure of the cells to platelet-activating factor (PAF, 200 nM), LTB(4) was measured by immunoassay, while neutrophil cytosolic Ca(2+) concentrations were determined by a fura-2/AM-based spectrofluorimetric procedure. Activation of neutrophils was accompanied by an abrupt and sustained (for about 1 min) elevation in cytosolic Ca(2+) which was associated with increased generation of LTB(4), both of which were attenuated significantly by itraconazole at 0.5 microM and higher. The inhibitory effect of the anti-mycotic on Ca(2+) uptake by PAF-activated cells was mimicked by an LTB(4) antibody, as well as by LY255283 (1 microM) and MK886 (0.5 microM), an antagonist of LTB(4) receptors and an inhibitor of 5'-lipoxygenase-activating protein, respectively, while addition of itraconazole to purified 5'-lipoxygenase resulted in inhibition of enzyme activity. A mechanistic relationship between itraconazole-mediated inhibition of LTB(4) production and Ca(2+) influx was also supported by the observation that pulsed addition of purified LTB(4) to PAF-activated neutrophils caused substantial restoration of Ca(2+) uptake by cells treated with the anti-mycotic. Taken together, these observations suggest that the potentially beneficial anti-inflammatory interactions of itraconazole with activated neutrophils result from interference with production of LTB(4), with consequent attenuation of a secondary LTB(4)-mediated wave of Ca(2+) uptake by the cells.
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Affiliation(s)
- H C Steel
- MRC Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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14
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Averna M, Stifanese R, De Tullio R, Defranchi E, Salamino F, Melloni E, Pontremoli S. Interaction between catalytically inactive calpain and calpastatin. Evidence for its occurrence in stimulated cells. FEBS J 2006; 273:1660-8. [PMID: 16623703 DOI: 10.1111/j.1742-4658.2006.05180.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Conformational changes in the calpain molecule following interaction with natural ligands can be monitored by the binding of a specific monoclonal antibody directed against the catalytic domain of the protease. None of these conformational states showed catalytic activity and probably represent intermediate forms preceding the active enzyme state. In its native inactive conformation, calpain shows very low affinity for this monoclonal antibody, whereas, on binding to the ligands Ca(2+), substrate or calpastatin, the affinity increases up to 10-fold, with calpastatin being the most effective. This methodology was also used to show that calpain undergoes similar conformational changes in intact cells exposed to stimuli that induce either a rise in intracellular [Ca(2+)] or extensive diffusion of calpastatin into the cytosol without affecting Ca(2+) homeostasis. The fact that the changes in the calpain state are also observed under the latter conditions indicates that calpastatin availability in the cytosol is the triggering event for calpain-calpastatin interaction, which is presumably involved in the control of the extent of calpain activation through translocation to specific sites of action.
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Affiliation(s)
- Monica Averna
- Department of Experimental Medicine (DIMES), Section of Biochemistry and Centre of Excellence for Biomedical Research (CEBR), University of Genova, Italy
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15
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Feldman C, Theron A, Anderson R. Neutrophils potentiate platinum-mediated injury to human ciliated epithelium in vitro. Inhal Toxicol 2005; 17:297-301. [PMID: 15814491 DOI: 10.1080/08958370590922607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Exposure to platinum salts, such as may occur in the platinum refining industry, can be associated with the development of airway disorders such as asthma. However, there have been no studies investigating the direct effects of platinum salts on human ciliated epithelium. We have investigated the effects of platinic chloride on human ciliated epithelium, obtained by brushing the inferior nasal turbinate of healthy human volunteers. Ciliary beat frequency was measured using a phototransistor technique, and damage to the structural integrity of the epithelium was measured using a visual scoring index. Platinic chloride at concentrations between 0.25 and 25 microM caused a dose-dependent slowing of ciliary beating and damage to the structural integrity of the epithelium. These direct injurious effects were not affected by catalase, but were almost completely attenuated by preincubation of the epithelium with cysteine. The effects of platinic chloride on ciliary beating and structural integrity were enhanced by the presence of neutrophils and were partially attenuated by preincubation of the epithelial strips with catalase, suggesting that the direct effects of the metal were enhanced in this experimental system by reactive oxidants produced by activated neutrophils. This study documents that platinum salts have an injurious effect on human ciliated epithelium in vitro. If such effects also occur in vivo they may play a role, at least partly, in the pathogenesis of airway disorders that may manifest in exposed workers.
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Affiliation(s)
- Charles Feldman
- Division of Pulmonology, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa.
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Tintinger G, Steel HC, Anderson R. Taming the neutrophil: calcium clearance and influx mechanisms as novel targets for pharmacological control. Clin Exp Immunol 2005; 141:191-200. [PMID: 15996182 PMCID: PMC1809444 DOI: 10.1111/j.1365-2249.2005.02800.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Neutrophils are relatively insensitive to the anti-inflammatory actions of conventional chemotherapeutic agents, including corticosteroids, emphasizing the requirement for novel pharmacological strategies to control the potentially harmful proinflammatory activities of these cells. In the case of commonly-occurring inflammatory diseases of the airways, the neutrophil is the primary mediator of inflammation in conditions such as chronic obstructive pulmonary disease, cystic fibrosis, acute respiratory distress syndrome, bronchiectasis and non-eosinophilic bronchial asthma. Recent insights into the mechanisms utilized by neutrophils to restore Ca(2+) homeostasis following activation with Ca(2+)-mobilizing, proinflammatory stimuli have facilitated the identification of novel targets for anti-inflammatory chemotherapy in these cells. The most amenable of these from a chemotherapeutic perspective, is the cyclic AMP-dependent protein kinase-modulated endomembrane Ca(2+)-ATPase which promotes clearance of the cation from the cytosol of activated neutrophils. Second generation type 4 phosphodiesterase inhibitors and adenosine receptor agonists operative at the level of subtype A2A adenosine receptors, which are currently undergoing clinical and preclinical assessment respectively, hold promise as pharmacologic modulators during the restoration of Ca(2+) homeostasis. If this promise is realized, it may result in novel chemotherapeutic strategies for the control of hyperacute and chronic inflammatory conditions in which neutrophils are primary offenders. Alternative, potential future targets include the Na(+), Ca(2+)-exchanger and store-operated Ca(2+) channels, which cooperate in the refilling of intracellular Ca(2+) stores.
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Affiliation(s)
- G Tintinger
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria, South Africa
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Anderson R, Steel HC, Tintinger GR. Inositol 1,4,5-triphosphate-mediated shuttling between intracellular stores and the cytosol contributes to the sustained elevation in cytosolic calcium in FMLP-activated human neutrophils. Biochem Pharmacol 2005; 69:1567-75. [PMID: 15896336 DOI: 10.1016/j.bcp.2005.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 03/09/2005] [Indexed: 11/22/2022]
Abstract
The current study was designed to probe Ca2+ shuttling between intracellular stores and the cytosol as a potential mechanism contributing to the prolongation of elevated Ca2+ transients in N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-activated human neutrophils. Cytosolic Ca2+ concentrations and transmembrane fluxes of the cation were measured using spectrofluorimetric and radiometric procedures, respectively, while inositol 1,4,5-triphosphate (IP3) was measured using a radioreceptor assay. The Ca2+-chelating agent, ethylene glycol-bis (beta-aminoethyl ether) N,N,N'N'-tetraacetic acid (EGTA; 10mM), was used to exclude store-operated influx of Ca2+ into neutrophils, while the IP3 receptor antagonist, 2-aminoethoxydiphenyl borate (2-APB, 100 microM), added to the cells 10s after FMLP (0.01 and 1 microM), at which time the increases in IP3 and cytosolic Ca2+ were maximal, was used to eliminate both sustained release from stores and influx of Ca2+. Addition of FMLP at 0.01 or 1 microM resulted in equivalent peak increases in cytosolic Ca2+, while the increase in IP3 was greater and the rate of clearance of Ca2+ from the cytosol slower, in cells activated with 1 microM FMLP. Treatment of the cells with either EGTA or 2-APB following addition of 1 microM FMLP, completely (EGTA) or almost completely (2-APB) abolished the influx of Ca2+ and accelerated the rate of clearance of the cation from the cytosol. Post-peak cytosolic Ca2+ concentrations were lower, and the Ca2+ content of the stores higher, in cells treated with 2-APB. The involvement of IP3 was confirmed by similar findings in cells treated with U-73122 (1 microM), a selective inhibitor of phospholipase C. Taken together, these observations are compatible with IP3-mediated Ca2+ shuttling in neutrophils activated with FMLP.
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Affiliation(s)
- Ronald Anderson
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria 0001, South Africa.
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Oommen J, Steel HC, Theron AJ, Anderson R. Investigation into the relationship between calyculin A-mediated potentiation of NADPH oxidase activity and inhibition of store-operated uptake of calcium by human neutrophils. Biochem Pharmacol 2004; 68:1721-8. [PMID: 15450937 DOI: 10.1016/j.bcp.2004.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2004] [Accepted: 07/13/2004] [Indexed: 11/18/2022]
Abstract
The primary objective of the current study was to investigate possible relationships between calyculin A (CA)-mediated potentiation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and inhibition of store-operated uptake of Ca2+ by chemoattractant-activated human neutrophils. Treatment of neutrophils with 100 nM CA, but not at lower concentrations (12.5-50 nM), prior to the addition of the N-formylated chemotactic tripeptide, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) (1 microM), both potentiated and prolonged the activity of NADPH oxidase which was accompanied by exaggerated membrane depolarisation, delayed and attenuated membrane repolarisation, and inhibition of store-operated Ca2+ influx. Inclusion of diphenylene iodonium chloride (DPI, 10 microM), an inhibitor of NADPH oxidase, antagonised the effects of CA on NADPH oxidase activity and the membrane repolarisation responses of FMLP-activated neutrophils, but failed to restore store-operated influx of Ca2+. Similarly, CA also inhibited store-operated influx of Ca2+ into FMLP-activated neutrophils from a patient with chronic granulomatous disease, a primary immunodeficiency disorder characterised by the absence of a functional NADPH oxidase. CA also inhibited the store-operated influx of Ca2+ into control neutrophils treated with 1 microM thapsigargin, a selective inhibitor of the endomembrane Ca2+-ATPase, which does not activate NADPH oxidase. Taken together, these observations demonstrate that augmentation of NADPH oxidase activity is not primarily involved in CA-mediated inhibition of the store-operated influx of Ca2+ into activated human neutrophils.
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Affiliation(s)
- Joyce Oommen
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa
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Tintinger GR, Anderson R. Counteracting effects of NADPH oxidase and the Na+/Ca2+ exchanger on membrane repolarisation and store-operated uptake of Ca2+ by chemoattractant-activated human neutrophils. Biochem Pharmacol 2004; 67:2263-71. [PMID: 15163557 DOI: 10.1016/j.bcp.2004.02.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2003] [Accepted: 02/18/2004] [Indexed: 10/26/2022]
Abstract
This study was designed to investigate the possible involvement of NADPH oxidase and the Na(+)/Ca(2+) exchanger in regulating membrane repolarisation and store-operated uptake of Ca(2+) by FMLP (1 microM)-activated human neutrophils. Diphenyleneiodonium chloride (DPI, 5-10 microM) and KB-R7943 (2.5-10 microM), inhibitors of NADPH oxidase and the reverse mode of the Na(+)/Ca(2+) exchanger respectively, were used as pharmacological probes. Transmembrane fluxes of Ca(2+), K(+) and Na(+) were determined radiometrically, while alterations in membrane potential and cytosolic Ca(2+) were evaluated using spectrofluorimetric procedures. DPI, added to the cells at the time of maximum FMLP-activated membrane depolarisation, accelerated the rates of both membrane repolarisation and influx of Ca(2+), while KB-R7943 effectively antagonised these processes. SKF 96365 (10 microM), an antagonist of store-operated Ca(2+) channels, abolished the influx of Ca(2+) into FMLP-activated neutrophils, but had no effects on membrane repolarisation, suggesting that the Na(+)/Ca(2+) exchanger is primarily involved in mediating membrane repolarisation, thereby facilitating uptake of Ca(2+) via store-operated channels. These observations are compatible with prominent negative and positive regulatory roles for NADPH oxidase and the Na(+)/Ca(2+) exchanger respectively in regulating the rates of membrane repolarisation and store-operated uptake of Ca(2+) by chemoattractant-activated neutrophils.
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Affiliation(s)
- Gregory R Tintinger
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Institute of Pathology, University of Pretoria, Pretoria, South Africa
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Steel HC, Anderson R. Itraconazole antagonizes store-operated influx of calcium into chemoattractant-activated human neutrophils. Clin Exp Immunol 2004; 136:255-61. [PMID: 15086388 PMCID: PMC1809014 DOI: 10.1111/j.1365-2249.2004.02443.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We have investigated the effects of itraconazole (0.1-10 micro m), an antimycotic which is often used prophylactically in primary and secondary immunodeficiency disorders, including chronic granulomatous disease, on mobilization of Ca(2+) and restoration of Ca(2+) homeostasis following activation of neutrophils with FMLP or PAF. Transmembrane fluxes of Ca(2+), as well as cytosolic concentrations of the cation were measured using a combination of spectrofluorimetric and radiometric procedures. The abruptly occurring increases in cytosolic Ca(2+) following activation of the cells with either FMLP (1 micro m) or PAF (200 nm) were unaffected by itraconazole. However, the subsequent store-operated influx of the cation was attenuated by itraconazole at concentrations of 0.25 micro m and higher. The itraconazole-mediated inhibition of uptake of Ca(2+) was not associated with detectable alterations in the intracellular concentrations of cyclic AMP, ATP or inositol triphosphate, and appeared to be compatible with antagonism of store-operated Ca(2+) channels. Although a secondary property, this anti-inflammatory activity of itraconazole, if operative in vivo, may be beneficial in conditions associated with dysregulation of neutrophil Ca(2+) handling such as CGD.
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Affiliation(s)
- H C Steel
- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Institute for Pathology, Faculty of Health Sciences, University of Pretoria, South Africa.
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Deo DD, Bazan NG, Hunt JD. Activation of platelet-activating factor receptor-coupled G alpha q leads to stimulation of Src and focal adhesion kinase via two separate pathways in human umbilical vein endothelial cells. J Biol Chem 2003; 279:3497-508. [PMID: 14617636 DOI: 10.1074/jbc.m304497200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Platelet-activating factor (PAF), a phospholipid second messenger, has diverse physiological functions, including responses in differentiated endothelial cells to external stimuli. We used human umbilical vein endothelial cells (HUVECs) as a model system. We show that PAF activated pertussis toxin-insensitive G alpha(q) protein upon binding to its seven transmembrane receptor. Elevated cAMP levels were observed via activation of adenylate cyclase, which activated protein kinase A (PKA) and was attenuated by a PAF receptor antagonist, blocking downstream activity. Phosphorylation of Src by PAF required G alpha(q) protein and adenylate cyclase activation; there was an absolute requirement of PKA for PAF-induced Src phosphorylation. Immediate (1 min) PAF-induced STAT-3 phosphorylation required the activation of G alpha(q) protein, adenylate cyclase, and PKA, and was independent of these intermediates at delayed (30 min) and prolonged (60 min) PAF exposure. PAF activated PLC beta 3 through its G alpha(q) protein-coupled receptor, whereas activation of phospholipase C gamma 1 (PLC gamma 1) by PAF was independent of G proteins but required the involvement of Src at prolonged PAF exposure (60 min). We demonstrate for the first time in vascular endothelial cells: (i) the involvement of signaling intermediates in the PAF-PAF receptor system in the induction of TIMP2 and MT1-MMP expression, resulting in the coordinated proteolytic activation of MMP2, and (ii) a receptor-mediated signal transduction cascade for the tyrosine phosphorylation of FAK by PAF. PAF exposure induced binding of p130(Cas), Src, SHC, and paxillin to FAK. Clearly, PAF-mediated signaling in differentiated endothelial cells is critical to endothelial cell functions, including cell migration and proteolytic activation of MMP2.
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Affiliation(s)
- Dayanand D Deo
- Department of Biochemistry and Molecular Biology, Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112, USA
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