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Dang PMC, Raad H, Derkawi RA, Boussetta T, Paclet MH, Belambri SA, Makni-Maalej K, Kroviarski Y, Morel F, Gougerot-Pocidalo MA, El-Benna J. The NADPH oxidase cytosolic component p67phox is constitutively phosphorylated in human neutrophils: Regulation by a protein tyrosine kinase, MEK1/2 and phosphatases 1/2A. Biochem Pharmacol 2011; 82:1145-52. [PMID: 21784060 DOI: 10.1016/j.bcp.2011.07.070] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 07/07/2011] [Accepted: 07/07/2011] [Indexed: 10/17/2022]
Abstract
Neutrophils play a key role in host defense and inflammation through the production of superoxide anion and other reactive oxygen species (ROS) by the enzyme complex NADPH oxidase. The cytosolic NADPH oxidase component, p67phox, has been shown to be phosphorylated in human neutrophils but the pathways involved in this process are largely unknown. In this study, we show that p67phox is constitutively phosphorylated in resting human neutrophils and that neutrophil stimulation with PMA further enhanced this phosphorylation. Inhibition of the constitutively active serine/threonine phosphatases type 1 and type 2A (PP1/2A) by calyculin A resulted in the enhancement of p67phox phosphorylation. Constitutive and calyculin A-induced phosphorylation of p67phox was completely inhibited by the protein tyrosine kinase inhibitor genistein and partially inhibited by the MEK1/2 inhibitor PD98059, but was unaffected by GF109203X, wortmannin and SB203580, inhibitors of PKC, PI3K and p38MAP kinase, respectively. Two-dimensional phosphopeptide mapping revealed that constitutive and calyculin A-induced p67phox phosphorylation occurred on the same major sites. Interestingly, calyculin A enhanced formyl-Met-Leu-Phe (fMLP)-induced superoxide production, while genistein inhibited this process. Taken together, these results suggest that (i) p67phox undergoes a continual cycle of phosphorylation/dephosphorylation in resting cells; (ii) p67phox phosphorylation is controlled by MEK1/2 and an upstream tyrosine kinase; (iii) PP1/2A directly or indirectly antagonize this process. Thus, these pathways could play a role in regulating ROS production by human neutrophils at inflammatory sites.
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Affiliation(s)
- Pham My-Chan Dang
- INSERM, U773, Centre de Recherche Biomédicale Bichat Beaujon CRB3, Paris F-75018, France
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152
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Ahmed SG. The role of infection in the pathogenesis of vaso-occlusive crisis in patients with sickle cell disease. Mediterr J Hematol Infect Dis 2011; 3:e2011028. [PMID: 21869914 PMCID: PMC3152450 DOI: 10.4084/mjhid.2011.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 06/06/2011] [Indexed: 01/08/2023] Open
Abstract
Sickle cell disease (SCD) is characterized by recurrent vaso-occlusive crisis (VOC). Patients with SCD have impaired immunity and are thus predispose to infections. The vast majority of SCD patients live in underdeveloped nations with high prevalence and transmission rates of infections. This makes the SCD patients prone to infections, which frequently precipitate VOC. We reviewed the role of infection in the pathogenesis of VOC, taking into consideration all potential mechanisms from previous studies and hypothetical perspectives. The potential mechanisms through which infections may lead to VOC involve several pathological changes including pneumonitis, pyrexia, acute phase reaction, hypercoagulability, neutrophilia, eosinophilia, thrombocytosis, bronchospasm, red cell cytopathic and membrane changes, auto-antibodies mediated red cell agglutination and opsonization, diarrhoea and vomiting, which may act singly or in concert to cause red cell sickling. These changes can induce sickling directly or indirectly through their adverse effects on Hb oxygenation and polymerization, hydration, blood viscosity, red cell metabolism, procoagulant activation, intercellular adherence and aggregation, culminating in VOC. There is therefore the need to ameliorate the burden of infection on SCD through immunization, prophylactic and therapeutic use of antimicrobials, barrier protection and vector control in communities with high prevalence of SCD.
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153
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Yun EY, Hwang JS, Yoon YI, Ahn MY, Kim NJ, Kwon OY, Lee WJ, Goo TW. Microarray expression profiling of Spodoptera litura in response to oxidative stress. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2011; 77:145-162. [PMID: 21678484 DOI: 10.1002/arch.20431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
To examine the expression profile of oxidative stress responsive genes in Spodoptera litura, we constructed a cDNA library from S. litura injected with hydrogen peroxide (H(2)O(2)). Using a microarray chip composed of 2,964 cDNAs, we screened gene expression at 1, 3, 5, 7, and 9 h post H(2)O(2) injection. Data were clustered into 15 groups of genes that behave similarly across each time course. Seventy-three genes were identified as being at least twofold up- or downregulated after treatment with H(2)O(2) in S. litura. We constructed expressed sequence tags (ESTs) for genes that changed at least twofold after treatment with H(2)O(2) . The functional classification of these ESTs based on Gene Ontology showed that the ESTs are rich in genes involved in oxidoreductase activity (5.7%), defense (14.3%), cellular process (22.9%), and development (17.1%).
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Affiliation(s)
- Eun-Young Yun
- Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon, South Korea
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154
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Treatment of anemia in heart failure: potential risks and benefits of intravenous iron therapy in cardiovascular disease. Cardiol Rev 2011; 18:240-50. [PMID: 20699672 DOI: 10.1097/crd.0b013e3181e71150] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Iron-deficiency anemia is common in patients with heart failure (HF), but the optimum diagnostic tests to detect iron deficiency and the treatment options to replete iron have not been fully characterized. Recent studies in patients with HF indicate that intravenous iron can rapidly replenish iron stores in patients having iron-deficiency anemia, with resultant increased hemoglobin levels and improved functional capacity. Preliminary data from a subgroup analysis also suggest that supplemental intravenous iron therapy can improve functional capacity even in those subjects without anemia. The mechanisms responsible for this observation are not fully characterized, but may be related to beneficial effects of iron supplementation on mitochondrial respiration in skeletal muscle. The long-term safety of using intravenous iron supplementation in HF populations is not known. Iron is a known pro-oxidant factor that can inhibit nitric oxide signaling and irreversibly injury cells. Increased iron stores are associated with vascular endothelial dysfunction and increased risk of coronary heart disease events. Additional clinical trials are needed to more fully characterize the therapeutic potential and safety of intravenous iron in HF patients.
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155
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Nair D, Dayyat EA, Zhang SX, Wang Y, Gozal D. Intermittent hypoxia-induced cognitive deficits are mediated by NADPH oxidase activity in a murine model of sleep apnea. PLoS One 2011; 6:e19847. [PMID: 21625437 PMCID: PMC3100309 DOI: 10.1371/journal.pone.0019847] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 04/18/2011] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND In rodents, exposure to intermittent hypoxia (IH), a hallmark of obstructive sleep apnea (OSA), is associated with neurobehavioral impairments, increased apoptosis in the hippocampus and cortex, as well as increased oxidant stress and inflammation. Excessive NADPH oxidase activity may play a role in IH-induced CNS dysfunction. METHODS AND FINDINGS The effect of IH during light period on two forms of spatial learning in the water maze and well as markers of oxidative stress was assessed in mice lacking NADPH oxidase activity (gp91phox(_/Y)) and wild-type littermates. On a standard place training task, gp91phox(_/Y) displayed normal learning, and were protected from the spatial learning deficits observed in wild-type littermates exposed to IH. Moreover, anxiety levels were increased in wild-type mice exposed to IH as compared to room air (RA) controls, while no changes emerged in gp91phox(_/Y) mice. Additionally, wild-type mice, but not gp91phox(_/Y) mice had significantly elevated levels of NADPH oxidase expression and activity, as well as MDA and 8-OHDG in cortical and hippocampal lysates following IH exposures. CONCLUSIONS The oxidative stress responses and neurobehavioral impairments induced by IH during sleep are mediated, at least in part, by excessive NADPH oxidase activity, and thus pharmacological agents targeting NADPH oxidase may provide a therapeutic strategy in sleep-disordered breathing.
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Affiliation(s)
- Deepti Nair
- Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Ehab A. Dayyat
- Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Shelley X. Zhang
- Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Yang Wang
- Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - David Gozal
- Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
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156
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Massaad CA, Klann E. Reactive oxygen species in the regulation of synaptic plasticity and memory. Antioxid Redox Signal 2011; 14:2013-54. [PMID: 20649473 PMCID: PMC3078504 DOI: 10.1089/ars.2010.3208] [Citation(s) in RCA: 406] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The brain is a metabolically active organ exhibiting high oxygen consumption and robust production of reactive oxygen species (ROS). The large amounts of ROS are kept in check by an elaborate network of antioxidants, which sometimes fail and lead to neuronal oxidative stress. Thus, ROS are typically categorized as neurotoxic molecules and typically exert their detrimental effects via oxidation of essential macromolecules such as enzymes and cytoskeletal proteins. Most importantly, excessive ROS are associated with decreased performance in cognitive function. However, at physiological concentrations, ROS are involved in functional changes necessary for synaptic plasticity and hence, for normal cognitive function. The fine line of role reversal of ROS from good molecules to bad molecules is far from being fully understood. This review focuses on identifying the multiple sources of ROS in the mammalian nervous system and on presenting evidence for the critical and essential role of ROS in synaptic plasticity and memory. The review also shows that the inability to restrain either age- or pathology-related increases in ROS levels leads to opposite, detrimental effects that are involved in impairments in synaptic plasticity and memory function.
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Affiliation(s)
- Cynthia A Massaad
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.
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157
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Kim JA, Neupane GP, Lee ES, Jeong BS, Park BC, Thapa P. NADPH oxidase inhibitors: a patent review. Expert Opin Ther Pat 2011; 21:1147-58. [DOI: 10.1517/13543776.2011.584870] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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158
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Garcia-Garcia E, Pun J, Perez-Estrada LA, Din MGE, Smith DW, Martin JW, Belosevic M. Commercial naphthenic acids and the organic fraction of oil sands process water downregulate pro-inflammatory gene expression and macrophage antimicrobial responses. Toxicol Lett 2011; 203:62-73. [PMID: 21396992 DOI: 10.1016/j.toxlet.2011.03.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Revised: 03/02/2011] [Accepted: 03/03/2011] [Indexed: 11/18/2022]
Abstract
This is the first report showing that the organic fraction of oil sands process water (OSPW-OF), and commercial naphthenic acids (C-NAs), cause immunotoxicity. The exposure of mouse bone marrow-derived macrophages (BMDM) to different amounts of C-NAs or OSPW-OF, did not affect cell viability in vitro. We examined whether exposure of BMDM to C-NAs or OSPW-OF affected various antimicrobial responses of these cells. A dose-dependent decrease in nitric oxide response was observed after treatment of BMDM with OSPW-OF, but not with C-NAs. Although OSPW-OF and C-NAs both down-regulated the respiratory burst response of BMDM, the suppression of the production of reactive oxygen intermediates was more pronounced in cells treated with OSPW-OF. Treatment with OSPW-OF or C-NAs reduced BMDM phagocytosis of zymosan and latex beads. The decrease of BMDM antimicrobial response after exposure to OSPW-OF or C-NAs, was accompanied by decreased pro-inflammatory cytokine gene expression. Oral exposure of mice to OSPW-OF caused down-regulation in the expression of genes encoding pro-inflammatory cytokines IFNγ, IL-1β and CSF-1. Our findings indicated that OSPW causes immunotoxic effects that may impair the ability of an exposed host to defend against infectious disease. Furthermore, given the differences between the effects of OSPW-OF and C-NAs, C-NAs should not be assumed to be a direct surrogate for the immunotoxic chemical species in OSPW.
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Affiliation(s)
- Erick Garcia-Garcia
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
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159
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Anh NTT, Nishitani M, Harada S, Yamaguchi M, Kamei K. A Drosophila model for the screening of bioavailable NADPH oxidase inhibitors and antioxidants. Mol Cell Biochem 2011; 352:91-8. [PMID: 21312054 DOI: 10.1007/s11010-011-0743-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2010] [Accepted: 01/28/2011] [Indexed: 11/26/2022]
Abstract
NADPH oxidase is the major source of non-mitochondrial cellular reactive oxygen species (ROS), and also is reported to be a major cause of various diseases including atherosclerosis and hypertension. In order to screen a new curative reagent that can suppress NADPH oxidase activity, we developed a Drosophila melanogaster fly that would overexpress human Dual oxidase 2 (hDuox2), a member of the NADPH oxidase family, as a screening model. These flies (GMR-GAL4/UAS-hDuox2) had a high generation of ROS in the posterior region of the eye discs along with an easily recognizable rough-eye phenotype, which is an ideal and convenient marker for further screening steps. Moreover, the hDuox2-induced rough-eye phenotype can be rescued by feeding with a culture medium containing mulberry leaves (MLs), which reportedly have an antimetabolic effect. Some commercially available antioxidants such as quercetin-3-O-D-glucoside or quercetin-3-O-glucose-6''-acetate, or the naringin contained in MLs and other herbs, also have shown a similar suppressing effect on the rough-eye phenotype. Our results suggest that flavonoid glycoside is absorbed from the intestine and functions in the body of D. melanogaster as it does in mammalian models such as rats. Thus, the GMR-GAL4/UAS-hDuox2 fly line is a promising model for the screening of novel drugs such as NADPH oxidase inhibitors and/or antioxidants.
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Affiliation(s)
- Nguyen Thi Tu Anh
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki Sakyo-ku, Kyoto, Japan
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160
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Mechanisms and consequences of bacterial targeting by the autophagy pathway. Curr Opin Microbiol 2011; 14:68-75. [DOI: 10.1016/j.mib.2010.11.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 11/02/2010] [Accepted: 11/02/2010] [Indexed: 02/05/2023]
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161
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Steinckwich N, Schenten V, Melchior C, Bréchard S, Tschirhart EJ. An essential role of STIM1, Orai1, and S100A8-A9 proteins for Ca2+ signaling and FcγR-mediated phagosomal oxidative activity. THE JOURNAL OF IMMUNOLOGY 2011; 186:2182-91. [PMID: 21239714 DOI: 10.4049/jimmunol.1001338] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Phagocytosis is a process of innate immunity that allows for the enclosure of pathogens within the phagosome and their subsequent destruction through the production of reactive oxygen species (ROS). Although these processes have been associated with increases of intracellular Ca(2+) concentrations, the mechanisms by which Ca(2+) could regulate the different phases of phagocytosis remain unknown. The aim of this study was to investigate the Ca(2+) signaling pathways involved in the regulation of FcγRs-induced phagocytosis. Our work focuses on IgG-opsonized zymosan internalization and phagosomal ROS production in DMSO-differentiated HL-60 cells and neutrophils. We found that chelation of intracellular Ca(2+) by BAPTA or emptying of the intracellular Ca(2+) store by thapsigargin reduced the efficiency of zymosan internalization. Using an small interfering RNA strategy, our data establish that the observed Ca(2+) release occurs through two isoforms of inositol 1,4,5-triphosphate receptors, ITPR1 and ITPR3. In addition, we provide evidence that phagosomal ROS production is dependent on extracellular Ca(2+) entry. We demonstrate that the observed Ca(2+) influx is supported by ORAI calcium release-activated calcium modulator 1 (Orai1) and stromal interaction molecule 1 (STIM1). This result suggests that extracellular Ca(2+) entry, which is required for ROS production, is mediated by a store-operated Ca(2+) mechanism. Finally, our data identify the complex formed by S100A8 and S100A9 (S100 calcium-binding protein A8 and A9 complex), two Ca(2+)-binding proteins, as the site of interplay between extracellular Ca(2+) entry and intraphagosomal ROS production. Thus, we demonstrate that FcγR-mediated phagocytosis requires intracellular Ca(2+) store depletion for the internalization phase. Then phagosomal ROS production requires extracellular Ca(2+) entry mediated by Orai1/STIM1 and relayed by S100A8-A9 as Ca(2+) sensor.
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Affiliation(s)
- Natacha Steinckwich
- Life Sciences Research Unit, University of Luxembourg, L-1511 Luxembourg, Luxembourg
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162
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Srikun D, Albers AE, Chang CJ. A dendrimer-based platform for simultaneous dual fluorescence imaging of hydrogen peroxide and pH gradients produced in living cells. Chem Sci 2011. [DOI: 10.1039/c1sc00064k] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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163
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ATP Released from Low-dose Gamma Ray-irradiated Cells Activates Intracellular Antioxidant Systems via Purine Receptors. ACTA ACUST UNITED AC 2011. [DOI: 10.3793/jaam.8.108] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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164
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Youn JI, Gabrilovich DI. The biology of myeloid-derived suppressor cells: the blessing and the curse of morphological and functional heterogeneity. Eur J Immunol 2010; 40:2969-75. [PMID: 21061430 DOI: 10.1002/eji.201040895] [Citation(s) in RCA: 437] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Myeloid-derived suppressor cells (MDSC) play an important role in the cellular network regulating immune responses in cancer, chronic infectious diseases, autoimmunity, and in other pathological conditions. Morphological, phenotypic and functional heterogeneity is a hallmark of MDSC. This heterogeneity demonstrates the plasticity of this immune suppressive myeloid compartment, and shows how various tumors and infectious agents can have similar biological effects on myeloid cells despite the differences in the factors that they produce to influence the immune system; however, such a heterogeneity creates ambiguity in the definition of MDSC as well as confusion regarding the origin and fate of these cells. In this review, we will discuss recent findings that help to better clarify these issues and to determine the place of MDSC within the myeloid cell lineage.
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Affiliation(s)
- Je-In Youn
- H. Lee Moffitt Cancer Center, Tampa, FL, USA
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165
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Miguel MG. Antioxidant and anti-inflammatory activities of essential oils: a short review. Molecules 2010; 15:9252-87. [PMID: 21160452 PMCID: PMC6259136 DOI: 10.3390/molecules15129252] [Citation(s) in RCA: 412] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 12/09/2010] [Accepted: 12/13/2010] [Indexed: 11/17/2022] Open
Abstract
Essential oils are complex mixtures isolated from aromatic plants which may possess antioxidant and anti-inflammatory activities of interest in thye food and cosmetic industries as well as in the human health field. In this work, a review was done on the most recent publications concerning their antioxidant and anti-inflammatory activities. At the same time a survey of the methods generally used for the evaluation of antioxidant activity and some of the mechanisms involved in the anti-inflammatory activities of essential oils are also reported.
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Affiliation(s)
- Maria Graça Miguel
- Faculdade de Ciências e Tecnologia, Universidade do Algarve, IBB, Centro de Biotecnologia Vegetal, Ed. 8, Campus de Gambelas, 8005-139 Faro, Portugal.
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166
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Anderson KE, Chessa TAM, Davidson K, Henderson RB, Walker S, Tolmachova T, Grys K, Rausch O, Seabra MC, Tybulewicz VLJ, Stephens LR, Hawkins PT. PtdIns3P and Rac direct the assembly of the NADPH oxidase on a novel, pre-phagosomal compartment during FcR-mediated phagocytosis in primary mouse neutrophils. Blood 2010; 116:4978-89. [PMID: 20813901 PMCID: PMC3368544 DOI: 10.1182/blood-2010-03-275602] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 08/14/2010] [Indexed: 11/20/2022] Open
Abstract
The generation of reactive oxygen species (ROS) by the nicotinamide adenine dinucleotide phosphate oxidase is an important mechanism by which neutrophils kill pathogens. The oxidase is composed of a membrane-bound cytochrome and 4 soluble proteins (p67(phox), p40(phox), p47(phox), and GTP-Rac). These components form an active complex at the correct time and subcellular location through a series of incompletely understood mutual interactions, regulated, in part, by GTP/GDP exchange on Rac, protein phosphorylation, and binding to lipid messengers. We have used a variety of assays to follow the spatiotemporal assembly of the oxidase in genetically engineered primary mouse neutrophils, during phagocytosis of both serum- and immunoglobulin G-opsonized targets. The oxidase assembles directly on serum-Staphylococcus aureus-containing phagosomes within seconds of phagosome formation; this process is only partially dependent (∼ 30%) on PtdIns3P binding to p40(phox), but totally dependent on Rac1/2 binding to p67(phox). In contrast, in response to immunoglobulin G-targets, the oxidase first assembles on a tubulovesicular compartment that develops at sites of granule fusion to the base of the emerging phagosome; oxidase assembly and activation is highly dependent on both PtdIns3P-p40(phox) and Rac2-p67(phox) interactions and delivery to the phagosome is regulated by Rab27a. These results define a novel pathway for oxidase assembly downstream of FcR-activation.
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Affiliation(s)
- Karen E Anderson
- Inositide Laboratory, Babraham Institute, Babraham Research Campus, Cambridge, UK
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167
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Evaluation of Vashe Wound Therapy in the clinical management of patients with chronic wounds. Adv Skin Wound Care 2010; 23:352-7. [PMID: 20664326 DOI: 10.1097/01.asw.0000383198.35815.a2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE To analyze if Vashe Wound Therapy (PuriCore, Malvern, Pennsylvania) is a valuable contribution to standard protocols of wound care. DESIGN Open, noncomparative study. SETTING Outpatient clinic. PATIENTS Thirty-one patients, primarily with venous or mixed venous/arterial leg ulcers. INTERVENTIONS Vashe Wound Therapy (hypochlorous acid, produced on site and on demand) was used as an adjunct to a standard wound care protocol. MAIN OUTCOME MEASURES Wound healing, reduction of pain, and odor. MAIN RESULTS At the end of the study, 86% of all lesions healed, and the average size of reduction in nonhealed wounds was 47%. Odor was present at the beginning of enrollment in 21 patients and was rated 4.58 on the visual analog scale. In all patients, the odor score at end of treatment was zero. Seventy-seven percent of all patients reported a positive pain score at the beginning of participation in the evaluation (average pain score, 4.7). At the end of the study, no patient experienced pain. CONCLUSION Vashe Wound Therapy is a valuable contribution to standard protocols of wound care.
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168
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Liu J, Zhou J, An W, Lin Y, Yang Y, Zang W. Apocynin attenuates pressure overload-induced cardiac hypertrophy in rats by reducing levels of reactive oxygen species. Can J Physiol Pharmacol 2010; 88:745-52. [PMID: 20651822 DOI: 10.1139/y10-063] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been shown that angiotensin II (Ang II) is involved in cardiac remodeling mediated by NADPH oxidase-dependent reactive oxygen species (ROS). Accordingly, NADPH oxidase-dependent ROS may play a role in cardiac hypertrophy induced by pressure overload. In the present study, we sought to determine whether inhibition of NADPH oxidase prevents cardiac hypertrophy. After abdominal aorta banding to induce cardiac hypertrophy, rats were treated for 8 weeks with apocynin (Apo) or captopril (Cap). Measures of cardiac hypertrophy were evaluated. Treatment with Cap or Apo reduced the left ventricle/body weight ratio (LV/BW), LV transnuclear myocyte diameter, and atrial natriuretic factor (ANF) mRNA expression relative to those of untreated rats subjected to aorta banding. The activity of NADPH oxidase and the ROS levels were decreased in treated animals. Cap, but not Apo, decreased Ang II levels and inhibited expression of p22phox and p67phox in LVs. In conclusion, local expression of Ang II appears to contribute to pressure overload-induced cardiac hypertrophy by upregulating NADPH oxidase expression and promoting ROS synthesis. Inhibition of NADPH oxidase and elimination of ROS may prevent or repair damage due to cardiac hypertrophy.
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Affiliation(s)
- Jinjun Liu
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi, China
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169
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Mazor Y, Karban A, Nesher S, Weiss B, Leshinsky-Silver E, Levine A, Eliakim R. Granulomas in Crohn's disease: are newly discovered genetic variants involved? J Crohns Colitis 2010; 4:438-43. [PMID: 21122541 DOI: 10.1016/j.crohns.2010.02.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 01/25/2010] [Accepted: 02/19/2010] [Indexed: 12/23/2022]
Abstract
BACKGROUND Non-caseating granulomas exist in a substantial portion of patients with Crohn's disease (CD). Several single nucleotide polymorphisms (SNPs) have been identified as a having strong association with CD, including SNPs within the autophagy related 4 homolog A (ATG4A) gene and the neutrophil cytosolic factor 4 (NCF4) gene. We hypothesized a possible association between the presence of granulomas in CD patients and variants in the ATG4A and NCF4 genes. AIMS To investigate whether variants in the NCF4 and ATG4A genes are associated with granuloma formation in a cohort of Israeli patients with CD, exploring demographic and clinical characteristics that differ between granuloma positive and granuloma negative patients. METHODS 307 Israeli patients with CD were studied. Patients with CD who underwent biopsy or resection of the intestine were classified according to presence or absence of granulomas. Using PCR-RFLP we determined the allele frequency in SNP rs4821544 (NCF4 gene) and SNP rs807185 (ATG4A gene) for all patients. RESULTS Granulomas were found in 85 out of 307 CD patients (27%). There were no significant differences between patients with or without granulomas in allele frequency in SNPs rs4821544 and rs807185. CD Patients with granuloma were younger at diagnosis than patients without granuloma (mean age 19 vs. 27, respectively, P<0.0001) and were more likely to undergo surgery (55.3% vs. 34.8%, respectively, P=0.002). CONCLUSIONS No association was found between SNPs rs4821544 and rs807185 and the presence of granulomas in CD patients. Granuloma positive patients were more likely to be younger and to undergo surgery.
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170
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Phosphorylation of threonine 154 in p40phox is an important physiological signal for activation of the neutrophil NADPH oxidase. Blood 2010; 116:6027-36. [PMID: 20861461 DOI: 10.1182/blood-2010-08-300889] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The neutrophil nicotinamide adenine dinucleotide phosphate-oxidase is a multisubunit enzyme (comprising gp91(phox), p22(phox), p67(phox), p40(phox), p47(phox), and Rac) that plays a vital role in microbial killing. The recent discovery of a chronic granulomatous disease patient who expresses a mutant p40(phox) subunit, together with the development of mouse models of p40(phox) function, indicate phosphatidylinositol 3-phosphate binding to the PX domain of p40(phox) is an important signal for oxidase activation. However, the presence of other conserved residues and domains in p40(phox) suggest further regulatory roles for this protein. To test this, we introduced wild-type and mutated versions of p40(phox) into fully differentiated mouse neutrophils by retroviral transduction of p40(phox)(-/-) bone marrow progenitors and repopulation of the bone marrow compartment in radiation chimaeras. Phosphorylation of p40(phox) on threonine 154, but not serine 315, was required for full oxidase activation in response to formylated bacterial peptide fMLP, serum-opsonized S aureus, and immunoglobulin-opsonized sheep red blood cells. A functional SH3 domain was not required for oxidase activation, and deletion of the entire domain resulted in enhanced oxidase responses. Phosphorylation of threonine 154 in response to S aureus was mediated by protein kinase Cδ and was required for full translocation of p47(phox) to phagosomes. These results define an important new element in the physiological activation of the oxidase.
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171
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Li L, Smith A, Hagen TM, Frei B. Vascular oxidative stress and inflammation increase with age: ameliorating effects of alpha-lipoic acid supplementation. Ann N Y Acad Sci 2010; 1203:151-9. [PMID: 20716298 DOI: 10.1111/j.1749-6632.2010.05555.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Increased oxidative stress and inflammation causally contribute to cardiovascular diseases, for which advanced age is a major risk factor. We found that indicators of oxidative stress, including NADPH oxidase activity and superoxide levels, were significantly increased in aortas of old (22-24 months) versus young (3-4 months) male F344 rats, whereas superoxide dismutase (SOD) activity was decreased. Aortic mRNA and protein levels of NOX4, the principal catalytic subunit of NADPH oxidase in vascular cells, also were increased with age, but not NOX2 and p22(phox). Indicators of inflammation, including activation of NFkappaB and upregulation of vascular cell adhesion molecule-1 (VCAM-1) in aorta, and monocyte chemotactic protein-1 (MCP-1) in plasma, also were significantly increased in old rats. Supplementation with 0.2% (wt/wt) (R)-alpha-lipoic acid (LA) for 2 weeks caused a nonsignificant decrease in NADPH oxidase activity in aged aorta and a significant decrease in mRNA--but not protein--levels of NOX4 and VCAM-1. Furthermore, LA reversed the age-dependent changes in aortic SOD activity and plasma MCP-1 levels. Hence, vascular oxidative stress and inflammation increase with age and are ameliorated by LA supplementation.
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Affiliation(s)
- Lixin Li
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, USA
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172
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Li XJ, Marchal CC, Stull ND, Stahelin RV, Dinauer MC. p47phox Phox homology domain regulates plasma membrane but not phagosome neutrophil NADPH oxidase activation. J Biol Chem 2010; 285:35169-79. [PMID: 20817944 DOI: 10.1074/jbc.m110.164475] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The assembly of cytosolic subunits p47(phox), p67(phox), and p40(phox) with flavocytochrome b(558) at the membrane is required for activating the neutrophil NADPH oxidase that generates superoxide for microbial killing. The p47(phox) subunit plays a critical role in oxidase assembly. Recent studies showed that the p47(phox) Phox homology (PX) domain mediates phosphoinositide binding in vitro and regulates phorbol ester-induced NADPH oxidase activity in a K562 myeloid cell model. Because the importance of the p47(phox) PX domain in neutrophils is unclear, we investigated its role using p47(phox) knock-out (KO) mouse neutrophils to express human p47(phox) and derivatives harboring R90A mutations in the PX domain that result in loss of phosphoinositide binding. Human p47(phox) proteins were expressed at levels similar to endogenous murine p47(phox), with the exception of a chronic granulomatous disease-associated R42Q mutant that was poorly expressed, and wild type human p47(phox) rescued p47(phox) KO mouse neutrophil NADPH oxidase activity. Plasma membrane NAPDH oxidase activity was reduced in neutrophils expressing p47(phox) with Arg(90) substitutions, with substantial effects on responses to either phorbol ester or formyl-Met-Leu-Phe and more modest effects to particulate stimuli. In contrast, p47(phox) Arg(90) mutants supported normal levels of intracellular NADPH oxidase activity during phagocytosis of a variety of particles and were recruited to phagosome membranes. This study defines a differential and agonist-dependent role of the p47(phox) PX domain for neutrophil NADPH oxidase activation.
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Affiliation(s)
- Xing Jun Li
- From the Department of Pediatrics (Hematology/Oncology), Herman B Wells Center for Pediatric Research, Riley Hospital for Children, and
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173
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Freitas M, Lima JL, Porto G, Fernandes E. Metal-induced oxidative burst in isolated human neutrophils. Microchem J 2010. [DOI: 10.1016/j.microc.2010.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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174
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Lam GY, Huang J, Brumell JH. The many roles of NOX2 NADPH oxidase-derived ROS in immunity. Semin Immunopathol 2010; 32:415-30. [DOI: 10.1007/s00281-010-0221-0] [Citation(s) in RCA: 163] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 08/08/2010] [Indexed: 12/27/2022]
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175
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Gray JP, Heart E. Usurping the mitochondrial supremacy: extramitochondrial sources of reactive oxygen intermediates and their role in beta cell metabolism and insulin secretion. Toxicol Mech Methods 2010; 20:167-74. [PMID: 20397883 DOI: 10.3109/15376511003695181] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Insulin secretion from pancreatic beta cells is a process dependent on metabolism. While oxidative stress is a well-known inducer of beta cell toxicity and impairs insulin secretion, recent studies suggest that low levels of metabolically-derived reactive oxygen intermediates (ROI) also play a positive role in insulin secretion. Glucose metabolism is directly correlated with ROI production, particularly in beta cells in which glucose uptake is proportional to the extracellular concentration of glucose. Low levels of exogenously added ROI or quinones, which stimulate ROI production, positively affect insulin secretion, while antioxidants block insulin secretion, suggesting that ROI activate unidentified redox-sensitive signal transduction components within these cells. The mitochondria are one source of ROI: increased metabolic flux increases mitochondrial membrane potential resulting in electron leakage and adventitious ROI production. A second source of ROI are cytosolic and plasma membrane oxidoreductases which oxidize NAD(P)H and directly produce ROI through the reduction of molecular oxygen. The mechanism of ROI-mediated potentiation of insulin secretion remains an important topic for future study.
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Affiliation(s)
- Joshua P Gray
- Department of Science, Chemistry Section, United States Coast Guard Academy, New London, CT 06320, USA.
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176
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Maehara Y, Miyano K, Yuzawa S, Akimoto R, Takeya R, Sumimoto H. A conserved region between the TPR and activation domains of p67phox participates in activation of the phagocyte NADPH oxidase. J Biol Chem 2010; 285:31435-45. [PMID: 20679349 DOI: 10.1074/jbc.m110.161166] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The phagocyte NADPH oxidase, dormant in resting cells, is activated during phagocytosis to produce superoxide, a precursor of microbicidal oxidants. The membrane-integrated protein gp91(phox) serves as the catalytic core, because it contains a complete electron-transporting apparatus from NADPH to molecular oxygen for superoxide production. Activation of gp91(phox) requires the cytosolic proteins p67(phox), p47(phox), and Rac (a small GTPase). p67(phox), comprising 526 amino acids, moves upon cell stimulation to the membrane together with p47(phox) and there interacts with Rac; these processes are prerequisite for gp91(phox) activation. Here we show that a region of p67(phox) (amino acids 190-200) C-terminal to the Rac-binding domain is evolutionarily well conserved and participates in oxidase activation at a later stage in conjunction with an activation domain. Alanine substitution for Tyr-198, Leu-199, or Val-204 abrogates the ability of p67(phox) to support superoxide production by gp91(phox)-based oxidase as well as its related oxidases Nox1 and Nox3; the activation also involves other invariant residues such as Leu-193, Asp-197, and Gly-200. Intriguingly, replacement of Gln-192 by alanine or that of Tyr-198 by phenylalanine or tryptophan rather enhances superoxide production by gp91(phox)-based oxidase, suggesting a tuning role for these residues. Furthermore, the Y198A/V204A or L199A/V204A substitution leads to not only a complete loss of the activity of the reconstituted oxidase system but also a significant decrease in p67(phox) interaction with the gp91(phox) NADPH-binding domain, although these mutations affect neither the protein integrity nor the Rac binding activity. Thus the extended activation domain of p67(phox) (amino acids 190-210) containing the D(Y/F)LGK motif plays an essential role in oxidase activation probably by interacting with gp91(phox).
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Affiliation(s)
- Yuichi Maehara
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka 812-8582, Japan
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177
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Klees RF, De Marco PC, Salasznyk RM, Ahuja D, Hogg M, Antoniotti S, Kamath L, Dordick JS, Plopper GE. Apocynin derivatives interrupt intracellular signaling resulting in decreased migration in breast cancer cells. J Biomed Biotechnol 2010; 2006:87246. [PMID: 16883056 PMCID: PMC1460968 DOI: 10.1155/jbb/2006/87246] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Cancer cells are defined by their ability to divide uncontrollably
and metastasize to secondary sites in the body. Consequently,
tumor cell migration represents a promising target for anticancer
drug development. Using our high-throughput cell migration assay,
we have screened several classes of compounds for noncytotoxic
tumor cell migration inhibiting activity. One such compound,
apocynin (4-acetovanillone), is oxidized by peroxidases to yield a
variety of oligophenolic and quinone-type compounds that are
recognized inhibitors of NADPH oxidase and may be inhibitors of
the small G protein Rac1 that controls cell migration. We report
here that while apocynin itself is not effective, apocynin
derivatives inhibit migration of the breast cancer cell line
MDA-MB-435 at subtoxic concentrations; the migration of
nonmalignant MCF10A breast cells is unaffected. These compounds
also cause a significant rearrangement of the actin cytoskeleton,
cell rounding, and decreased levels of active Rac1 and its related
G protein Cdc42. These results may suggest a promising new route
to the development of novel anticancer therapeutics.
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Affiliation(s)
- Robert F. Klees
- Department of Biology, Rensselaer Polytechnic Institute,
Troy, NY 12180, USA
| | - Paul C. De Marco
- Department of Biology, Rensselaer Polytechnic Institute,
Troy, NY 12180, USA
| | - Roman M. Salasznyk
- Department of Biology, Rensselaer Polytechnic Institute,
Troy, NY 12180, USA
| | - Disha Ahuja
- Department of Chemical and Biological Engineering, Rensselaer
Polytechnic Institute, Troy, NY 12180, USA
| | - Michael Hogg
- Department of Chemical and Biological Engineering, Rensselaer
Polytechnic Institute, Troy, NY 12180, USA
| | - Sylvain Antoniotti
- Department of Chemical and Biological Engineering, Rensselaer
Polytechnic Institute, Troy, NY 12180, USA
| | - Lakshmi Kamath
- Life Sciences Division, Millipore Corporation,
Danvers, MA 01923, USA
| | - Jonathan S. Dordick
- Department of Chemical and Biological Engineering, Rensselaer
Polytechnic Institute, Troy, NY 12180, USA
| | - George E. Plopper
- Department of Biology, Rensselaer Polytechnic Institute,
Troy, NY 12180, USA
- *George E. Plopper:
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178
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Abstract
Recent research has unraveled a number of unexpected functions of the pyridine nucleotides. In this review, we will highlight the variety of known physiological roles of NADP. In its reduced form (NADPH), this molecule represents a universal electron donor, not only to drive biosynthetic pathways. Perhaps even more importantly, NADPH is the unique provider of reducing equivalents to maintain or regenerate the cellular detoxifying and antioxidative defense systems. The roles of NADPH in redox sensing and as substrate for NADPH oxidases to generate reactive oxygen species further extend its scope of functions. NADP(+), on the other hand, has acquired signaling functions. Its conversion to second messengers in calcium signaling may have critical impact on important cellular processes. The generation of NADP by NAD kinases is a key determinant of the cellular NADP concentration. The regulation of these enzymes may, therefore, be critical to feed the diversity of NADP-dependent processes adequately. The increasing recognition of the multiple roles of NADP has thus led to exciting new insights in this expanding field.
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Affiliation(s)
- Line Agledal
- Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway
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179
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Mizrahi A, Berdichevsky Y, Casey PJ, Pick E. A prenylated p47phox-p67phox-Rac1 chimera is a Quintessential NADPH oxidase activator: membrane association and functional capacity. J Biol Chem 2010; 285:25485-99. [PMID: 20529851 DOI: 10.1074/jbc.m110.113779] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The superoxide-generating NADPH oxidase complex of resting phagocytes includes cytochrome b(559), a membrane-associated heterodimer composed of two subunits (Nox2 and p22(phox)), and four cytosolic proteins (p47(phox), p67(phox), Rac, and p40(phox)). Upon stimulation, the cytosolic components translocate to the membrane, as the result of a series of interactions among the cytosolic components and among the cytosolic components and cytochrome b(559) and its phospholipid environment. We described the construction of a tripartite chimera (trimera) consisting of strategic domains of p47(phox), p67(phox), and Rac1, in which interactions among cytosolic components were replaced by fusion (Berdichevsky, Y., Mizrahi, A., Ugolev, Y., Molshanski-Mor, S., and Pick, E. (2007) J. Biol. Chem. 282, 22122-22139). We now fused green fluorescent protein (GFP) to the N terminus of the trimera and found the following. 1) The GFP-p47(phox)-p67(phox)-Rac1 trimera activates the oxidase in amphiphile-dependent and -independent (anionic phospholipid-enriched membrane) cell-free systems. 2) Geranylgeranylation of the GFP-trimera makes it a potent oxidase activator in unmodified (native) membranes and in the absence of amphiphile. 3) Prenylated GFP-trimera binds spontaneously to native membranes (as assessed by gel filtration and in-line fluorometry), forming a tight complex capable of NADPH-dependent, activator-independent superoxide production at rates similar to those measured in canonical cell-free systems. 4) Prenylation of the GFP-trimera supersedes completely the dependence of oxidase activation on the p47(phox) phox homology domain and, partially, on the Rac1 polybasic domain, but the requirement for Trp(193) in p47(phox) persists. Prenylated GFP-p47(phox)-p67(phox)-Rac1 trimera acts as a quintessential single molecule oxidase activator of potential use in high throughput screening of inhibitors.
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Affiliation(s)
- Ariel Mizrahi
- Julius Friedrich Cohnheim Laboratory of Phagocyte Research, Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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180
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Brunati AM, Pagano MA, Bindoli A, Rigobello MP. Thiol redox systems and protein kinases in hepatic stellate cell regulatory processes. Free Radic Res 2010; 44:363-78. [PMID: 20166884 DOI: 10.3109/10715760903555836] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatic stellate cells (HSC) are the major producers of collagen in the liver and their conversion from resting cells to a proliferating, contractile and fibrogenic phenotype ('activation') is a critical step, leading to liver fibrosis characterized by deposition of excessive extracellular matrix. Cytokines, growth factors, reactive oxygen and nitrogen species (ROS/RNS), lipid peroxides and their products deriving from hepatocytes, Kupffer cells and other cells converge on HSC and influence their activation. This review focuses on glutathione and thioredoxin pathways, with particular emphasis on their role in HSC. These two systems have been shown to act in the metabolism of hydrogen peroxide, control of thiol redox balance and regulation of signalling pathways. Particular attention is paid to mitochondria and NADPH oxidase. Detailed knowledge of specific signalling, redox conditions and apoptotic processes will be of help in devising proper pharmacological treatments for liver fibrosis.
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Affiliation(s)
- Anna Maria Brunati
- Dipartimento di Chimica Biologica, Viale G. Colombo 3, 35121 Padova, Italy.
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181
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Ostuni MA, Lamanuzzi LB, Bizouarn T, Dagher MC, Baciou L. Expression of functional mammal flavocytochrome b558 in yeast: Comparison with improved insect cell system. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:1179-88. [DOI: 10.1016/j.bbamem.2010.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 01/22/2010] [Accepted: 02/12/2010] [Indexed: 11/29/2022]
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182
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Rafts and the battleships of defense: The multifaceted microdomains for positive and negative signals in immune cells. Immunol Lett 2010; 130:2-12. [DOI: 10.1016/j.imlet.2009.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2009] [Revised: 12/13/2009] [Accepted: 12/13/2009] [Indexed: 11/20/2022]
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183
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Saalu LC. The incriminating role of reactive oxygen species in idiopathic male infertility: an evidence based evaluation. Pak J Biol Sci 2010; 13:413-422. [PMID: 20973394 DOI: 10.3923/pjbs.2010.413.422] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The male factor is considered a major contributory factor to infertility. Apart from the conventional causes for male infertility such as varicocoele, cryptorchidism, infections, obstructive lesions, cystic fibrosis, trauma and tumours, a new and important cause has been identified as being responsible for the so-called idiopathic male infertility: oxidative stress. Oxidative Stress (OS) is a condition that occurs when the production of Reactive Oxygen Species (ROS) overwhelms the antioxidant defense produced against them. In male reproductive pathological conditions, the OS significantly impairs spermatogenesis and sperm function, which may lead to male infertility. Reactive Oxygen Species (ROS) known as free radicals are oxidizing agents generated as a result of metabolism of oxygen and have at least one unpaired electron that make them very reactive species. Spermatozoa generate Reactive Oxygen Species (ROS) in physiological amounts, which play a role in sperm functions during sperm capacitation, Acrosome Reaction (AR) and oocyte fusion, but they need to be controlled and their concentrations maintained at a level that is not deleterious to the cells. Administration of antioxidants in patients with 'male factor' infertility has begun to attract considerable interest. The main difficulty of such an approach is our incomplete understanding of the role of free radicals in normal and abnormal sperm function leading to male infertility. The purpose of the present review is to address the relationship between ROS and idiopathic male factor infertility.
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Affiliation(s)
- L C Saalu
- Department of Anatomy, Lagos State University College of Medicine, Ikeja, Lagos, Nigeria
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184
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Williams R, Yao H, Peng F, Yang Y, Bethel-Brown C, Buch S. Cooperative induction of CXCL10 involves NADPH oxidase: Implications for HIV dementia. Glia 2010; 58:611-21. [PMID: 19941336 DOI: 10.1002/glia.20949] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
With the increasing prevalence of HIV-associated neurocognititve disorders (HAND), understanding the mechanisms by which HIV-1 induces neuro-inflammation and subsequent neuronal damage is important. The hallmark features of HIV-encephalitis, the pathological correlate of HIV-associated Dementia (HAD), are gliosis, oxidative stress, chemokine dysregulation, and neuronal damage/death. Since neurons are not infected by HIV-1, the current thinking is that these cells are damaged indirectly by pro-inflammatory chemokines released by activated glial cells. CXCL10 is a neurotoxic chemokine that is upregulated in astroglia activated by HIV-1 Tat, IFN-gamma, and TNF-alpha. In this study we have demonstrated that HIV-1 Tat increases CXCL10 expression in IFN-gamma and TNF-alpha stimulated human astrocytes via NADPH oxidase. We have shown that the treatment of astrocytes with a mixture of Tat and cytokines leads to a respiratory burst that is abrogated by apocynin, an NADPH oxidase inhibitor. Pretreatment of Tat, IFN-gamma, and TNF-alpha stimulated astrocytes with apocynin also resulted in concomitant inhibition of CXCL10 expression. Additionally, apocynin was also able to reduce Tat and cytokine-mediated activation of the corresponding signaling molecules Erk1/2, Jnk, and Akt with a decrease in activation and nuclear translocation of NF-kappaB, important regulators of CXCL10 induction. Understanding the mechanisms involved in reducing both oxidative stress and the release of pro-inflammatory agents could lead to the development of therapeutics aimed at decreasing neuro-inflammation in patients suffering from HAD.
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Affiliation(s)
- Rachel Williams
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, USA
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185
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Seitz PM, Cooper R, Gatto GJ, Ramon F, Sweitzer TD, Johns DG, Davenport EA, Ames RS, Kallal LA. Development of a high-throughput cell-based assay for superoxide production in HL-60 cells. ACTA ACUST UNITED AC 2010; 15:388-97. [PMID: 20228280 DOI: 10.1177/1087057109359687] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Superoxide affects many normal and pathogenic cellular processes, and the detection of superoxide produced by cells is therefore of interest for potential therapeutic applications. To develop a high-throughput cell-based assay for the detection of extracellular superoxide production that could be run in a 384-well or 1536-well format, 2 luminescent reagents, Lucigenin and Diogenes, and one fluorescent reagent, Oxyburst Green BSA, were tested. HL-60 cells, which had been differentiated to a neutrophil-like phenotype with DMSO and frozen in large batches, were used in assays. All 3 superoxide detection reagents performed well statistically in terms of IC(50) reproducibility and met a desired Z' value requirement of >0.4. When tested against a 1408-compound test set at 5 or 10 microM compound concentration, a higher hit rate was obtained with the 2 luminescent reagents compared with that obtained with the fluorescent Oxyburst Green BSA reagent. The Oxyburst Green BSA assay was ultimately chosen for compound profiling and high-throughput screening activities. This 1536 superoxide detection assay using cryopreserved differentiated HL-60 cells represents a shifting paradigm toward the utilization of more therapeutically relevant cells in early drug development activities.
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Affiliation(s)
- Patricia M Seitz
- Department of Screening and Compound Profiling, GlaxoSmithKline R&D, Collegeville, Pennsylvania 19426, USA
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186
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187
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Hawkins PT, Stephens LR, Suire S, Wilson M. PI3K signaling in neutrophils. Curr Top Microbiol Immunol 2010; 346:183-202. [PMID: 20473789 DOI: 10.1007/82_2010_40] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PI3Ks play important roles in the signaling pathways used by a wide variety of cell surface receptors on neutrophils. Class IB PI3K plays a major role in the initial generation of PtdIns(3,4,5)P₃ by Gi-coupled G-protein coupled receptors (GPCRs) (e.g., receptors for fMLP, C5a, LTB₄). Class IA PI3Ks generate PtdIns(3,4,5)P₃ downstream of receptors which directly or indirectly couple to protein tyrosine kinases such as integrins, FcγRs, cytokine receptors, and GPCRs. The PtdIns(3,4,5)P₃ made by Class I PI3Ks regulates the activity of several different effector proteins, many of which are plasma membrane GEFs or GAPs for small GTPases. Class III PI3K generates PtdIns(3)P in the phagosome membrane and plays an important role in efficient assembly of the NADPH oxidase at this location. Much still remains to be discovered about the molecular details that govern activation of PI3Ks and the mechanisms by which these enzymes regulate complex cellular processes, such as neutrophil spreading, chemotaxis, phagocytosis, and killing of pathogens. However, it is clear from recent use of transgenic mouse models and isoform-selective PI3K inhibitors that these pathways are important in regulating neutrophil recruitment to sites of infection and damage in vivo. Thus, PI3K pathways may present novel opportunities for selective inhibition in some inflammatory pathologies.
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Affiliation(s)
- Phillip T Hawkins
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK.
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188
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Pourova J, Kottova M, Voprsalova M, Pour M. Reactive oxygen and nitrogen species in normal physiological processes. Acta Physiol (Oxf) 2010; 198:15-35. [PMID: 19732041 DOI: 10.1111/j.1748-1716.2009.02039.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract Reactive oxygen species (ROS) and reactive nitrogen species have generally been considered as being highly reactive and cytotoxic molecules. Besides their noxious effects, ROS participate in physiological processes in a carefully regulated manner. By way of example, microbicidal ROS are produced in professional phagocytes, ROS function as short-lived messengers having a role in signal transduction and, among other processes, participate in the synthesis of the iodothyronine hormones, reproduction, apoptosis and necrosis. Because of their ability to mediate a crosstalk between key molecules, their role might be dual (at least in some cases). The levels of ROS increase from a certain age, being associated with various diseases typical of senescence. The aim of this review is to summarize the recent findings on the physiological role of ROS. Other issues addressed are an increase in ROS levels during ageing, and the possibility of the physiological nature of this process.
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Affiliation(s)
- J Pourova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Prague, Czech Republic.
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189
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Shim JW, Jo SH, Kim SD, Lee HY, Yun J, Bae YS. Lysophosphatidylglycerol inhibits formyl peptide receptorlike-1-stimulated chemotactic migration and IL-1beta production from human phagocytes. Exp Mol Med 2009; 41:584-91. [PMID: 19381066 DOI: 10.3858/emm.2009.41.8.064] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
In this study, we observed that lysophosphatidylglycerol (LPG) completely inhibited a formyl peptide receptor like-1 (FPRL1) agonist (MMK-1)-stimulated chemotactic migration in human phagocytes, such as neutrophils and monocytes. LPG also dramatically inhibited IL-1beta production by another FPRL1 agonist serum amyloid A (SAA) in human phagocytes. However, LPG itself induced intracellular calcium increase and superoxide anion production in human phagocytes. Keeping in mind that phagocytes migration and IL-1beta production by FPRL1 are important for the induction of inflammatory response, our data suggest that LPG can be regarded as a useful material for the modulation of inflammatory response induced by FPRL1 activation.
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Affiliation(s)
- Jae Woong Shim
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, Korea
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190
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Kobayashi SD. Role of neutrophils in innate immunity: a systems biology-level approach. WILEY INTERDISCIPLINARY REVIEWS. SYSTEMS BIOLOGY AND MEDICINE 2009; 1:309-333. [PMID: 20836000 PMCID: PMC3501127 DOI: 10.1002/wsbm.32] [Citation(s) in RCA: 170] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The innate immune system is the first line of host defense against invading microorganisms. Polymorphonuclear leukocytes (PMNs or neutrophils) are the most abundant leukocyte in humans and essential to the innate immune response against invading pathogens. Compared with the acquired immune response, which requires time to develop and is dependent on previous interaction with specific microbes, the ability of neutrophils to kill microorganisms is immediate, non-specific, and not dependent on previous exposure to microorganisms. Historically, studies on PMN-pathogen interaction focused on the events leading to killing of microorganisms, such as recruitment/chemotaxis, transmigration, phagocytosis, and activation, whereas post-phagocytosis sequelae were infrequently considered. In addition, it was widely accepted that human neutrophils possessed limited capacity for new gene transcription and thus, relatively little biosynthetic capacity. This notion has changed dramatically within the past decade. Further, there is now more effort directed to understand the events occurring in PMNs after killing of microbes. Herein we review the systems biology-level approaches that have been used to gain an enhanced view of the role of neutrophils during host-pathogen interaction. We anticipate that these and future systems-level studies will ultimately provide information critical to our understanding, treatment, and control of diseases caused by pathogenic microorganisms.
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Affiliation(s)
- Scott D. Kobayashi
- Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health
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191
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Csányi G, Taylor WR, Pagano PJ. NOX and inflammation in the vascular adventitia. Free Radic Biol Med 2009; 47:1254-66. [PMID: 19628034 PMCID: PMC3061339 DOI: 10.1016/j.freeradbiomed.2009.07.022] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 07/10/2009] [Accepted: 07/14/2009] [Indexed: 02/07/2023]
Abstract
Vascular inflammation has traditionally been thought to be initiated at the luminal surface and progress through the media toward the adventitial layer. In recent years, however, evidence has emerged suggesting that the vascular adventitia is activated early in a variety of cardiovascular diseases and that it plays an important role in the initiation and progression of vascular inflammation. Adventitial fibroblasts have been shown to produce substantial amounts of NAD(P)H oxidase-derived reactive oxygen species (ROS) in response to vascular injury. Additionally, inflammatory cytokines, lipids, and various hormones, implicated in fibroblast proliferation and migration, lead to recruitment of inflammatory cells to the adventitial layer and impairment of endothelium-dependent relaxation. Early in the development of vascular disease, there is clear evidence for progression toward a denser vasa vasorum which delivers oxygen and nutrients to an increasingly hypoxic and nutrient-deficient media. This expanded vascularization appears to provide enhanced delivery of inflammatory cells to the adventitia and outer media. Combined adventitial fibroblast and inflammatory cell-derived ROS therefore are expected to synergize their local effect on adventitial parenchymal cells, leading to further cytokine release and a feed-forward propagation of adventitial ROS production. In fact, data from our laboratory and others suggest a broader paracrine positive feedback role for adventitia-derived ROS in medial smooth muscle cell hypertrophy and neointimal hyperplasia. A likely candidate responsible for the adventitia-derived paracrine signaling across the vessel wall is the superoxide anion metabolite hydrogen peroxide, which is highly stable, cell permeant, and capable of activating downstream signaling mechanisms in smooth muscle cells, leading to phenotypic modulation of smooth muscle cells. This review addresses the role of adventitial NAD(P)H oxidase-derived ROS from a nontraditional, perivascular vantage of promoting vascular inflammation and will discuss how ROS derived from adventitial NAD(P)H oxidases may be a catalyst for vascular remodeling and dysfunction.
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Affiliation(s)
- Gábor Csányi
- Department of Pharmacology & Chemical Biology and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
| | - W. Robert Taylor
- Departments of Medicine and Biomedical Engineering, Emory University and the Atlanta VA Medical Center, Atlanta, GA
| | - Patrick J. Pagano
- Department of Pharmacology & Chemical Biology and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
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192
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The glycosylphosphatidylinositol-anchored protease Sap9 modulates the interaction of Candida albicans with human neutrophils. Infect Immun 2009; 77:5216-24. [PMID: 19805528 DOI: 10.1128/iai.00723-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human polymorphonuclear neutrophils (PMNs) play a major role in the immune defense against invasive Candida albicans infection. This fungal pathogen produces a set of aspartic proteases that directly contributes to virulence properties such as adhesion, tissue invasion, and immune evasion. We show here that, in contrast to other secreted proteases, the cell surface-associated isoform Sap9 has a major impact on the recognition of C. albicans by PMNs. SAP9 is required for the induction of PMN chemotaxis toward C. albicans filaments, an essential prerequisite of effective PMN activation. Furthermore, deletion of SAP9 leads to a mitigated release of reactive oxygen intermediates (ROI) in human PMNs and decreases C. albicans-induced apoptosis triggered by ROI formation. In confrontation assays, killing of a SAP9 deletion mutant is reduced in comparison to wild-type C. albicans. These data clearly implicate Sap9 protease activity in the initiation of protective innate immunity and suggest novel molecular mechanisms in C. albicans-host interaction leading to neutrophil activation.
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193
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Bokoch GM, Diebold B, Kim JS, Gianni D. Emerging evidence for the importance of phosphorylation in the regulation of NADPH oxidases. Antioxid Redox Signal 2009; 11:2429-41. [PMID: 19358632 PMCID: PMC2821133 DOI: 10.1089/ars.2009.2590] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The NADPH oxidase (Nox) enzyme family generates reactive oxygen species (ROS) that contribute to cell signaling, innate immune responses, proliferation, and transcription. The signaling mechanisms that regulate this important enzyme family are only beginning to be understood. Evidence is emerging which suggests that phosphorylation of Nox and/or their regulatory components may be important means of modulating their activity. We describe here the evidence for Nox regulation through the action of kinases, and speculate on how such regulatory mechanisms might contribute to the development of pathological disease states.
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Affiliation(s)
- Gary M Bokoch
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA.
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194
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Gianni D, Diaz B, Taulet N, Fowler B, Courtneidge SA, Bokoch GM. Novel p47(phox)-related organizers regulate localized NADPH oxidase 1 (Nox1) activity. Sci Signal 2009; 2:ra54. [PMID: 19755710 DOI: 10.1126/scisignal.2000370] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The mechanisms that determine localized formation of reactive oxygen species (ROS) through NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase (Nox) family members in nonphagocytic cells are unknown. We show that the c-Src substrate proteins Tks4 (tyrosine kinase substrate with four SH3 domains) and Tks5 are functional members of a p47(phox)-related organizer superfamily. Tks proteins selectively support Nox1 and Nox3 (and not Nox2 and Nox4) activity in reconstituted cellular systems and interact with the NoxA1 activator protein through an Src homology 3 domain-mediated interaction. Endogenous Tks4 is required for Rac guanosine triphosphatase- and Nox1-dependent ROS production by DLD1 colon cancer cells. Our results are consistent with the Tks-mediated recruitment of Nox1 to invadopodia that form in DLD1 cells in a Tks- and Nox-dependent fashion. We propose that Tks organizers represent previously unrecognized members of an organizer superfamily that link Nox to localized ROS formation.
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Affiliation(s)
- Davide Gianni
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
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195
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Baciou L, Erard M, Dagher MC, Bizouarn T. The cytosolic subunit p67phox of the NADPH-oxidase complex does not bind NADPH. FEBS Lett 2009; 583:3225-9. [PMID: 19751728 DOI: 10.1016/j.febslet.2009.09.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 09/03/2009] [Accepted: 09/06/2009] [Indexed: 12/16/2022]
Abstract
The NADPH-oxidase of phagocytic cells is a multicomponent enzyme that generates superoxide. It comprises a membrane flavocytochrome b558 and four cytosolic proteins; p67phox, p47phox, p40phox and Rac. The NADPH-binding site of this complex was shown to be located on the flavocytochrome b558. However, a number of studies have suggested the presence of another site on the p67phox subunit which is the key activating component. Using several approaches like tryptophan quenching fluorescence measurement, inhibition by 2',3'-dialdehyde NADPH, and free/bound NADPH concentration measurements, we demonstrate that no NADPH binds on p67phox, thus definitively solving the controversy on the number and location of the NADPH-binding sites on this complex.
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Affiliation(s)
- Laura Baciou
- Laboratoire de Chimie-Physique, UMR 8000-CNRS, Université Paris-Sud, Orsay, France
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196
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Optical probes for detection and quantification of neutrophils’ oxidative burst. A review. Anal Chim Acta 2009; 649:8-23. [DOI: 10.1016/j.aca.2009.06.063] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Revised: 06/25/2009] [Accepted: 06/29/2009] [Indexed: 11/20/2022]
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197
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Ce-Duox1/BLI-3 generates reactive oxygen species as a protective innate immune mechanism in Caenorhabditis elegans. Infect Immun 2009; 77:4983-9. [PMID: 19687201 DOI: 10.1128/iai.00627-09] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Caenorhabditis elegans was recently developed as a model system to study both pathogen virulence mechanisms and host defense responses. We previously demonstrated that C. elegans produces reactive oxygen species (ROS) in response to exposure to the important gram-positive nosocomial pathogen Enterococcus faecalis. We also presented evidence of oxidative stress and upregulation of stress responses after exposure to the pathogen. As in mammalian systems, this new work shows that production of ROS for innate immune functions occurs via an NADPH oxidase. Specifically, reducing expression of a dual oxidase, Ce-Duox1/BLI-3, causes a decrease in ROS production in response to E. faecalis. We also present evidence that reduction of expression of Ce-Duox1/BLI-3 increases susceptibility to this pathogen, specifically when expression is reduced in the intestine and the hypodermis. Ce-Duox1/BLI-3 was previously characterized as having a role in cuticle cross-linking. Two C. elegans mutants with point mutations in the peroxidase domain that exhibit severe cuticle defects were discovered to be unaffected in ROS production or pathogen susceptibility. These results demonstrate an important biological role for the peroxidase domain in cuticle cross-linking that is unrelated to ROS production. To further demonstrate the protective effects of the pathogen-induced ROS production, we show that antioxidants that scavenge ROS increase the sensitivity of the nematode to the infection, in stark contrast to their longevity-promoting effects under nonpathogenic conditions. In conclusion, we postulate that the generation of ROS by NADPH oxidases in the barrier epithelium is an ancient, highly conserved innate immune defense mechanism.
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198
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Subcellular localization of Nox4 and regulation in diabetes. Proc Natl Acad Sci U S A 2009; 106:14385-90. [PMID: 19706525 DOI: 10.1073/pnas.0906805106] [Citation(s) in RCA: 390] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Oxidative stress is implicated in human diseases. Some of the oxidative pathways are harbored in the mitochondria. NAD(P)H oxidases have been identified not only in phagocytic but also in somatic cells. Nox4 is the most ubiquitous of these oxidases and is a major source of reactive oxygen species (ROS) in many cell types and in kidney tissue of diabetic animals. We generated specific Nox4 antibodies, and found that Nox4 localizes to mitochondria. (i) Immunoblot analysis in cultured mesangial cells and kidney cortex revealed that Nox4 is present in crude mitochondria, in mitochondria-enriched heavy fractions, and in purified mitochondria; (ii) immunofluorescence confocal microscopy also revealed that Nox4 localizes with the mitochondrial marker Mitotracker; and (iii) the mitochondrial localization prediction program MitoProt indicated that the probability score for Nox4 is identical to mitochondrial protein cytochrome c oxidase subunit IV. We also show that in purified mitochondria, siRNA-mediated knockdown of Nox4 significantly reduces NADPH oxidase activity in pure mitochondria and blocks glucose-induced mitochondrial superoxide generation. In a rat model of diabetes, mitochondrial Nox4 expression is increased in kidney cortex. Our data provide evidence that a functional Nox4 is present and regulated in mitochondria, indicating the existence of a previously undescribed source of ROS in this organelle.
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199
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Gunnarsson P, Fornander L, Påhlsson P, Grenegård M. Sialic acid residues play a pivotal role in α1-acid glycoprotein (AGP)-induced generation of reactive oxygen species in chemotactic peptide pre-activated neutrophil granulocytes. Inflamm Res 2009; 59:89-95. [DOI: 10.1007/s00011-009-0071-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/23/2009] [Accepted: 07/18/2009] [Indexed: 10/20/2022] Open
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200
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Boussetta T, Raad H, Lettéron P, Gougerot-Pocidalo MA, Marie JC, Driss F, El-Benna J. Punicic acid a conjugated linolenic acid inhibits TNFalpha-induced neutrophil hyperactivation and protects from experimental colon inflammation in rats. PLoS One 2009; 4:e6458. [PMID: 19649246 PMCID: PMC2714468 DOI: 10.1371/journal.pone.0006458] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 07/03/2009] [Indexed: 12/31/2022] Open
Abstract
Background Neutrophils play a major role in inflammation by releasing large amounts of ROS produced by NADPH-oxidase and myeloperoxidase (MPO). The proinflammatory cytokine TNFα primes ROS production through phosphorylation of the NADPH-oxidase subunit p47phox on Ser345. Conventional anti-inflammatory therapies remain partially successful and may have side effects. Therefore, regulation of neutrophil activation by natural dietary components represents an alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases. The aim of this study was to assess the effect of punicic acid, a conjugated linolenic fatty acid from pomegranate seed oil on TNFα-induced neutrophil hyperactivation in vitro and on colon inflammation in vivo. Methodology and Principal Findings We analyzed the effect of punicic acid on TNFα-induced neutrophil upregulation of ROS production in vitro and on TNBS-induced rat colon inflammation. Results show that punicic acid inhibited TNFα-induced priming of ROS production in vitro while preserving formyl-methionyl-leucyl-phenylalanine (fMLP)-induced response. This effect was mediated by the inhibition of Ser345-p47phox phosphorylation and upstream kinase p38MAPK. Punicic acid also inhibited fMLP- and TNFα+fMLP-induced MPO extracellular release from neutrophils. In vivo experiments showed that punicic acid and pomegranate seed oil intake decreased neutrophil-activation and ROS/MPO-mediated tissue damage as measured by F2-isoprostane release and protected rats from TNBS-induced colon inflammation. Conclusions/Significance These data show that punicic acid exerts a potent anti-inflammatory effect through inhibition of TNFα-induced priming of NADPH oxidase by targeting the p38MAPKinase/Ser345-p47phox-axis and MPO release. This natural dietary compound may provide a novel alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases.
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Affiliation(s)
- Tarek Boussetta
- INSERM, U773, Université Paris, Faculté de Médecine, Paris, France
| | - Houssam Raad
- INSERM, U773, Université Paris, Faculté de Médecine, Paris, France
| | | | - Marie-Anne Gougerot-Pocidalo
- INSERM, U773, Université Paris, Faculté de Médecine, Paris, France
- Assistance Publique Hopitaux De Paris (AP-HP), Centre Hospitalo-Universitaire Xavier Bichat, CIB Phenogen, Paris, France
| | | | - Fathi Driss
- INSERM, U773, Université Paris, Faculté de Médecine, Paris, France
- Assistance Publique Hopitaux De Paris (AP-HP), Centre Hospitalo-Universitaire Xavier Bichat, CIB Phenogen, Paris, France
- Université de Versailles Saint Quentin en Yvelines, Versailles, France
- * E-mail: (FD); (JE)
| | - Jamel El-Benna
- INSERM, U773, Université Paris, Faculté de Médecine, Paris, France
- * E-mail: (FD); (JE)
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