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Moreno R, Sobotzik JM, Schultz C, Schmitz ML. Specification of the NF-kappaB transcriptional response by p65 phosphorylation and TNF-induced nuclear translocation of IKK epsilon. Nucleic Acids Res 2010; 38:6029-44. [PMID: 20507904 PMCID: PMC2952868 DOI: 10.1093/nar/gkq439] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Here we investigated the regulation of NF-κB activity by post-translational modifications upon reconstitution of NF-κB p65-deficient cells with the wild-type protein or phosphorylation-defect mutants. Analysis of NF-κB target gene expression showed that p65 phosphorylations alone or in combination function to direct transcription in a highly target gene-specific fashion, a finding discussed here as the NF-κB barcode hypothesis. High-resolution microscopy and surface rendering revealed serine 536 phosphorylated p65 predominantly in the cytosol, while serine 468 phosphorylated p65 mainly localized in nuclear speckles. TNF stimulation resulted in the translocation of the cytosolic p65 kinase IKKε to the nucleus and also to promyelocytic leukemia (PML) nuclear bodies. This inducible IKKε translocation was dependent on p65 phosphorylation and was prevented by the oncogenic PML-RARα fusion protein. Chromatin immunoprecipitation experiments revealed the inducible association of IKKε to the control regions of several NF-κB target genes. In the nucleus, the kinase contributes to the expression of a subset of NF-κB-regulated genes, thus revealing a novel role of IKKε for the control of nuclear NF-κB activity.
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Affiliation(s)
- Rita Moreno
- Institute of Biochemistry, Medical Faculty, Friedrichstrasse 24, Justus-Liebig-University, 35392 Giessen, Germany
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102
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Dal-Secco D, Freitas A, Abreu MA, Garlet TP, Rossi MA, Ferreira SH, Silva JS, Alves-Filho JC, Cunha FQ. Reduction of ICAM-1 expression by carbon monoxide via soluble guanylate cyclase activation accounts for modulation of neutrophil migration. Naunyn Schmiedebergs Arch Pharmacol 2010; 381:483-93. [PMID: 20349048 DOI: 10.1007/s00210-010-0500-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 02/12/2010] [Indexed: 02/08/2023]
Abstract
Previously, it was demonstrated that the heme/heme oxygenase (HO)/carbon monoxide (CO) pathway inhibits neutrophil recruitment during the inflammatory response. Herein, we addressed whether the inhibitory effect of the HO pathway on neutrophil adhesion and migration involves the reduction of intracellular adhesion molecule type (ICAM)-1 and beta(2)-integrin expression. Mice pretreated with a specific inhibitor of inducible HO (HO-1), zinc protoporphyrin (ZnPP) IX, exhibit enhanced neutrophil adhesion and migration induced by intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS). These findings are associated with an increase in ICAM-1 expression on mesentery venular endothelium. In accordance, HO-1 inhibition did not enhance LPS-induced neutrophil migration and adhesion in ICAM-1-deficient mice. Furthermore, the treatment with a CO donor (dimanganese decacarbonyl, DMDC) that inhibits adhesion and migration of the neutrophils, reduced LPS-induced ICAM-1 expression. Moreover, neither DMDC nor ZnPP IX treatments changed LPS-induced beta(2)-integrin expression on neutrophils. The effect of CO on ICAM-1 expression seems to be dependent on soluble guanylate cyclase (sGC) activation, since 1H-(1,2,4)oxadiazolo (4,3-a)quinoxalin-1-one (sGC inhibitor) prevented the observed CO effects. Finally, it was observed that the nitric oxide (NO) anti-inflammatory effects on ICAM-1 expression appear to be indirectly mediated by HO-1 activation, since the inhibition of HO-1 prevented the inhibitory effect of the NO donor (S-nitroso-N-acetylpenicillamine) on LPS-induced ICAM-1 expression. Taken together, these results suggest that CO inhibits ICAM-1 expression on endothelium by a mechanism dependent on sGC activation. Thus, our findings identify the HO-1/CO/guanosine 3'5'-cyclic monophosphate pathway as a potential target for the development of novel pharmacotherapy to control neutrophil migration in inflammatory diseases.
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Affiliation(s)
- Daniela Dal-Secco
- Department of Pharmacology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Avenida Bandeirantes, 3900, 14049-900, Ribeirao Preto, Sao Paulo, Brazil
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103
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Abstract
Heme oxygenases (HO) catabolize free heme, that is, iron (Fe) protoporphyrin (IX), into equimolar amounts of Fe(2+), carbon monoxide (CO), and biliverdin. The stress-responsive HO-1 isoenzyme affords protection against programmed cell death. The mechanism underlying this cytoprotective effect relies on the ability of HO-1 to catabolize free heme and prevent it from sensitizing cells to undergo programmed cell death. This cytoprotective effect inhibits the pathogenesis of a variety of immune-mediated inflammatory diseases.
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104
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Heme oxygenase (HO)-1 protects from lipopolysaccharide (LPS)-mediated liver injury by inhibition of hepatic leukocyte accumulation and improvement of microvascular perfusion. Langenbecks Arch Surg 2010; 395:387-94. [PMID: 20237939 DOI: 10.1007/s00423-010-0603-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 01/26/2010] [Indexed: 02/06/2023]
Abstract
PURPOSE Lipopolysaccharide (LPS) represents a highly toxic substance which may aggravate morbidity and mortality in septic diseases. A recent study has reported that the induction of heme oxygenase (HO)-1 protects from LPS-induced liver injury. The mechanisms of action however, have not been clarified yet. Therefore, we analyzed in vivo the effects of HO-1 on the liver microcirculation under conditions of LPS exposure. METHODS In C57BL/6 mice, endotoxemia was induced by intraperitoneal (i.p.) administration of LPS (500 microg/kg) and D-galactosamine (Gal, 800 mg/kg). HO-1 was induced in vivo by pretreatment with hemin dissolved in DMSO (50 micromol/kg i.p.). Animals treated with DMSO only served as controls. Six hours after LPS exposure the hepatic microcirculation and leukocyte-endothelial cell interaction were analyzed by intravital fluorescence microscopy. HO-1 expression was determined by Western blot analysis. Hepatocellular damage was assessed by measuring the serum levels of aspartate aminotransferase and alanine aminotransferase. In addition, leukocyte transmigration and hepatocellular apoptosis were analyzed by histology and immunohistochemistry. RESULTS In controls, LPS/Gal caused severe liver injury, as indicated by increased liver enzyme levels and apoptotic cell death. This was associated with distinct sinusoidal perfusion failure and microvascular intrahepatic leukocyte accumulation. Of interest, induction of HO-1 significantly reduced numbers of adherent and extravascular leukocytes when compared to controls. Moreover, microvascular perfusion was significantly improved, resulting in a decrease of AST and ALT and a reduction of hepatocellular apoptosis. CONCLUSIONS Our novel data indicate that induction of HO-1 protects the liver from LPS-mediated injury by reducing leukocytic inflammation and improving intrahepatic microcirculation.
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González-Ramos R, Van Langendonckt A, Defrère S, Lousse JC, Colette S, Devoto L, Donnez J. Involvement of the nuclear factor-κB pathway in the pathogenesis of endometriosis. Fertil Steril 2010; 94:1985-94. [PMID: 20188363 DOI: 10.1016/j.fertnstert.2010.01.013] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 01/05/2010] [Accepted: 01/08/2010] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To evaluate the role of nuclear factor-κB (NF-κB) in the pathogenesis of endometriosis. DESIGN A literature search was conducted in PubMed to identify all relevant citations. RESULT(S) Our findings highlight the important role of NF-κB in the pathophysiology of endometriosis. In vitro and in vivo studies show that NF-κB-mediated gene transcription promotes inflammation, invasion, angiogenesis, and cell proliferation and inhibits apoptosis of endometriotic cells. Constitutive activation of NF-κB has been demonstrated in endometriotic lesions and peritoneal macrophages of endometriosis patients. Agents blocking NF-κB are effective inhibitors of endometriosis development and some drugs with known NF-κB inhibitory properties have proved efficient at reducing endometriosis-associated symptoms in women. Iron overload activates NF-κB in macrophages. NF-κB activation in macrophages and ectopic endometrial cells stimulates synthesis of proinflammatory cytokines, generating a positive feedback loop in the NF-κB pathway and promoting endometriotic lesion establishment, maintenance and development. CONCLUSION(S) NF-κB transcriptional activity modulates key cell processes contributing to the initiation and progression of endometriosis. Because endometriosis is a multifactorial disease, inhibiting NF-κB appears to be a promising strategy for future therapies targeting different cell functions involved in endometriosis development, such as cell adhesion, invasion, angiogenesis, inflammation, proliferation, and apoptosis. Upcoming research will elucidate these hypotheses.
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Affiliation(s)
- Reinaldo González-Ramos
- Instituto de Investigaciones Materno Infantil, Departamento de Obstetricia y Ginecología, Hospital Clínico San Borja-Arriarán, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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Kim J, Surh YJ. The Role of Nrf2 in Cellular Innate Immune Response to Inflammatory Injury. Toxicol Res 2009; 25:159-173. [PMID: 32038834 PMCID: PMC7006253 DOI: 10.5487/tr.2009.25.4.159] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 12/02/2009] [Indexed: 12/16/2022] Open
Abstract
Nuclear factor erythroid derived 2-related factor-2 (Nrf2) is a master transcription regulator of antioxidant and cytoprotective proteins that mediate cellular defense against oxidative and inflammatory stresses. Disruption of cellular stress response by Nrf2 deficiency causes enhanced susceptibility to infection and related inflammatory diseases as a consequence of exacerbated immuneediated hypersensitivity and autoimmunity. The cellular defense capacity potentiated by Nrf2 activation appears to balance the population of CD4+ and CD8+ of lymph node cells for proper innate immune responses. Nrf2 can negatively regulate the activation of pro-inflammatory signaling molecules such as p38 MAPK, NF-KB, and AP-1. Nrf2 subsequently functions to inhibit the production of pro-inflammatory mediators including cytokines, chemokines, cell adhesion molecules, matrix metalloprotein-ases, COX-2 and iNOS. Although not clearly elucidated, the antioxidative function of genes targeted by Nrf2 may cooperatively regulate the innate immune response and also repress the expression of proinflammatory mediators.
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Affiliation(s)
- Jiyoung Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, 599 Kwanak-ro, Kwanak-gu, Seoul, 151-742 Korea
| | - Young-Joon Surh
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, 599 Kwanak-ro, Kwanak-gu, Seoul, 151-742 Korea
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Lacraz G, Giroix MH, Kassis N, Coulaud J, Galinier A, Noll C, Cornut M, Schmidlin F, Paul JL, Janel N, Irminger JC, Kergoat M, Portha B, Donath MY, Ehses JA, Homo-Delarche F. Islet endothelial activation and oxidative stress gene expression is reduced by IL-1Ra treatment in the type 2 diabetic GK rat. PLoS One 2009; 4:e6963. [PMID: 19742300 PMCID: PMC2737103 DOI: 10.1371/journal.pone.0006963] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 08/03/2009] [Indexed: 02/07/2023] Open
Abstract
Background Inflammation followed by fibrosis is a component of islet dysfunction in both rodent and human type 2 diabetes. Because islet inflammation may originate from endothelial cells, we assessed the expression of selected genes involved in endothelial cell activation in islets from a spontaneous model of type 2 diabetes, the Goto-Kakizaki (GK) rat. We also examined islet endotheliuml/oxidative stress (OS)/inflammation-related gene expression, islet vascularization and fibrosis after treatment with the interleukin-1 (IL-1) receptor antagonist (IL-1Ra). Methodology/Principal Findings Gene expression was analyzed by quantitative RT-PCR on islets isolated from 10-week-old diabetic GK and control Wistar rats. Furthermore, GK rats were treated s.c twice daily with IL-1Ra (Kineret, Amgen, 100 mg/kg/day) or saline, from 4 weeks of age onwards (onset of diabetes). Four weeks later, islet gene analysis and pancreas immunochemistry were performed. Thirty-two genes were selected encoding molecules involved in endothelial cell activation, particularly fibrinolysis, vascular tone, OS, angiogenesis and also inflammation. All genes except those encoding angiotensinogen and epoxide hydrolase (that were decreased), and 12-lipoxygenase and vascular endothelial growth factor (that showed no change), were significantly up-regulated in GK islets. After IL-1Ra treatment of GK rats in vivo, most selected genes implied in endothelium/OS/immune cells/fibrosis were significantly down-regulated. IL-1Ra also improved islet vascularization, reduced fibrosis and ameliorated glycemia. Conclusions/Significance GK rat islets have increased mRNA expression of markers of early islet endothelial cell activation, possibly triggered by several metabolic factors, and also some defense mechanisms. The beneficial effect of IL-1Ra on most islet endothelial/OS/immune cells/fibrosis parameters analyzed highlights a major endothelial-related role for IL-1 in GK islet alterations. Thus, metabolically-altered islet endothelium might affect the β-cell microenvironment and contribute to progressive type 2 diabetic β-cell dysfunction in GK rats. Counteracting islet endothelial cell inflammation might be one way to ameliorate/prevent β-cell dysfunction in type 2 diabetes.
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Affiliation(s)
- Grégory Lacraz
- Laboratory of Biology & Pathology of Endocrine Pancreas, Functional and Adaptive Biology Unit-CNRS EA 7059, University Paris-Diderot, Paris, France
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108
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Silva G, Jeney V, Chora A, Larsen R, Balla J, Soares MP. Oxidized hemoglobin is an endogenous proinflammatory agonist that targets vascular endothelial cells. J Biol Chem 2009; 284:29582-95. [PMID: 19700768 DOI: 10.1074/jbc.m109.045344] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Several pathologic conditions are associated with hemolysis, i.e. release of ferrous (Fe(II)) hemoglobin from red blood cells. Oxidation of cell-free hemoglobin produces (Fe(III)) methemoglobin. More extensive oxidation produces (Fe(III)/Fe(IV) O) ferryl hemoglobin. Both cell-free methemoglobin and ferryl hemoglobin are thought to contribute to the pathogenesis of hemolytic disorders. We show hereby that ferryl hemoglobin, but not hemoglobin or methemoglobin, acts as a potent proinflammatory agonist that induces vascular endothelial cells in vitro to rearrange the actin cytoskeleton, forming intercellular gaps and disrupting the integrity of the endothelial cell monolayer. Furthermore, ferryl hemoglobin induces the expression of proinflammatory genes in endothelial cells in vitro, e.g. E-selectin, Icam-1, and Vcam-1, through the activation of the nuclear factor kappaB family of transcription factors. This proinflammatory effect, which requires actin polymerization, involves the activation of the c-Jun N-terminal kinase and the p38 mitogen-activated protein kinase signal transduction pathways. When administered to naïve mice, ferryl hemoglobin induces the recruitment of polymorphonuclear cells, demonstrating that it acts as a proinflammatory agonist in vivo. In conclusion, oxidized hemoglobin, i.e. ferryl hemoglobin, acts as a proinflammatory agonist that targets vascular endothelial cells.
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Affiliation(s)
- Gabriela Silva
- Instituto Gulbenkian de Ciência, Oeiras 2780-156, Portugal
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109
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Song H, Bergstrasser C, Rafat N, Höger S, Schmidt M, Endres N, Goebeler M, Hillebrands JL, Brigelius-Flohé R, Banning A, Beck G, Loesel R, Yard BA. The carbon monoxide releasing molecule (CORM-3) inhibits expression of vascular cell adhesion molecule-1 and E-selectin independently of haem oxygenase-1 expression. Br J Pharmacol 2009; 157:769-80. [PMID: 19422386 DOI: 10.1111/j.1476-5381.2009.00215.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE Although carbon monoxide (CO) can modulate inflammatory processes, the influence of CO on adhesion molecules is less clear. This might be due to the limited amount of CO generated by haem degradation. We therefore tested the ability of a CO releasing molecule (CORM-3), used in supra-physiological concentrations, to modulate the expression of vascular cell adhesion molecule (VCAM)-1 and E-selectin on endothelial cells and the mechanism(s) involved. EXPERIMENTAL APPROACH Human umbilical vein endothelial cells (HUVECs) were stimulated with tumour necrosis factor (TNF)-alpha in the presence or absence of CORM-3. The influence of CORM-3 on VCAM-1 and E-selectin expression and the nuclear factor (NF)-kappaB pathway was assessed by flow cytometry, Western blotting and electrophoretic mobility shift assay. KEY RESULTS CORM-3 inhibited the expression of VCAM-1 and E-selectin on TNF-alpha-stimulated HUVEC. VCAM-1 expression was also inhibited when CORM-3 was added 24 h after TNF-alpha stimulation or when TNF-alpha was removed. This was paralleled by deactivation of NF-kappaB and a reduction in VCAM-1 mRNA. Although TNF-alpha removal was more effective in this regard, VCAM-1 protein was down-regulated more rapidly when CORM-3 was added. CORM-3 induced haem oxygenase-1 (HO-1) in a dose- and time-dependent manner, mediated by the transcription factor, Nrf2. CORM-3 was still able to down-regulate VCAM-1 expression in HUVEC transfected with siRNA for HO-1 or Nrf2. CONCLUSIONS AND IMPLICATIONS Down-regulation of VCAM and E-selectin expression induced by CORM-3 was independent of HO-1 up-regulation and was predominantly due to inhibition of sustained NF-kappaB activation.
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Affiliation(s)
- H Song
- Vth Medical Department, University Hospital Mannheim, Mannheim, Germany
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110
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Wang L, Cherayil BJ. Ironing out the wrinkles in host defense: interactions between iron homeostasis and innate immunity. J Innate Immun 2009; 1:455-64. [PMID: 20375603 DOI: 10.1159/000210016] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 01/16/2009] [Indexed: 12/15/2022] Open
Abstract
Iron is an essential micronutrient for both microbial pathogens and their mammalian hosts. Changes in iron availability and distribution have significant effects on pathogen virulence and on the immune response to infection. Recent advances in our understanding of the molecular regulation of iron metabolism have shed new light on how alterations in iron homeostasis both contribute to and influence innate immunity. In this article, we review what is currently known about the role of iron in the response to infection.
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Affiliation(s)
- Lijian Wang
- Mucosal Immunology Laboratory, Massachusetts General Hospital, Charlestown, MA, USA
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111
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Takamiya R, Hung CC, Hall SR, Fukunaga K, Nagaishi T, Maeno T, Owen C, Macias AA, Fredenburgh LE, Ishizaka A, Blumberg RS, Baron RM, Perrella MA. High-mobility group box 1 contributes to lethality of endotoxemia in heme oxygenase-1-deficient mice. Am J Respir Cell Mol Biol 2008; 41:129-35. [PMID: 19097991 DOI: 10.1165/rcmb.2008-0331oc] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
High-mobility group box 1 (HMGB1) is a nuclear protein that has been found to be a critical mediator of lethality in endotoxemia and sepsis. During the systemic inflammatory response, circulating levels of HMGB1 are increased, but in a delayed fashion compared with early inflammatory mediators. To counteract the inflammatory response of endotoxemia, a secondary anti-inflammatory response ensues in an attempt to prevent inflammation-induced tissue injury. One such cytoprotective gene that is induced during endotoxemia is heme oxygenase (HO)-1. HO-1, and its products of heme metabolism, possess anti-inflammatory and antioxidant properties to counter the damaging effects of endotoxemia. In the present study, we wanted to determine whether tissue and circulating levels of HMGB1 are increased further in the absence of HO-1 during endotoxemia, and whether this increase may contribute to the pathobiology of endotoxemia. Lung inflammation, HMGB1 protein levels, and expression of HMGB1 in inflammatory cells were increased in HO-1(-/-) mice compared with HO-1+/+ mice. After the administration of LPS, tissue levels of HMGB1 were not increased further in HO-1(-/-) mice; however, circulating levels of HMGB1 were higher when compared with HO-1+/+ mice. HO-1(-/-) mice treated with a carbon monoxide-releasing molecule or biliverdin showed a reduction in plasma HMGB1, which was associated with a marked improvement in survival. HO-1(-/-) mice given HMGB1-neutralizing antibody showed improvement in survival compared with control antibody. These data suggest that exaggerated circulating levels of HMGB1 contribute to endotoxin-induced mortality in the absence of HO-1.
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Affiliation(s)
- Rina Takamiya
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, 75 Francis St., Boston, MA 02115, USA
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112
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Heme oxygenase-1 expression enhances vascular endothelial resistance to complement-mediated injury through induction of decay-accelerating factor: a role for increased bilirubin and ferritin. Blood 2008; 113:1598-607. [PMID: 19036700 DOI: 10.1182/blood-2008-04-152934] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Catabolism of free heme by heme oxygenase-1 (HO-1) generates carbon monoxide, biliverdin, and free iron (Fe). These end-products are responsible for much of the biologic activity of HO-1, including anti-inflammatory, antiapo-ptotic, antiproliferative, and antioxidant effects. We have identified an additional cytoprotective action, the regulation of complement activation, mediated via induction of decay-accelerating factor (DAF). Pharmacologic inhibition or short-interfering RNA (siRNA) depletion of HO-1 prevented induction of DAF expression in human endothelial cells. In contrast, HO-1 agonists hemin and cobalt protoporphyrin IX significantly increased DAF protein expression, reflecting an increase in transcription and steady-state mRNA. Adenoviral-mediated overexpression of HO-1 increased DAF expression, enhancing protection against C3 deposition and complement-mediated lysis, and this was reversed by DAF inhibitory monoclonal antibody (mAb) 1H4. Likewise, bilirubin, Fe chelation, and overexpression of heavy-chain ferritin all induced DAF expression in endothelial cells (EC). Analysis of cardiac endothelial cells isolated from Hmox1(-/-) mice revealed a 60% reduction in DAF expression compared with Hmox1(+/+) EC, and Hmox1(-/-) cells showed enhanced sensitivity to complement. We propose that modulation of complement activation through induction of DAF represents an important component of the cytoprotective effects of HO-1 against vascular injury, such as that associated with posttransplant vasculopathy, allograft rejection, and ischemia reperfusion.
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113
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Naidu S, Wijayanti N, Santoso S, Kietzmann T, Immenschuh S. An Atypical NF-κB-Regulated Pathway Mediates Phorbol Ester-Dependent Heme Oxygenase-1 Gene Activation in Monocytes. THE JOURNAL OF IMMUNOLOGY 2008; 181:4113-23. [DOI: 10.4049/jimmunol.181.6.4113] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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114
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Li X, Schwacha MG, Chaudry IH, Choudhry MA. Heme oxygenase-1 protects against neutrophil-mediated intestinal damage by down-regulation of neutrophil p47phox and p67phox activity and O2- production in a two-hit model of alcohol intoxication and burn injury. THE JOURNAL OF IMMUNOLOGY 2008; 180:6933-40. [PMID: 18453614 DOI: 10.4049/jimmunol.180.10.6933] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Heme oxygenase-1 (HO-1) has been demonstrated to protect against tissue injury. Furthermore, HO-1 is also shown to be antioxidant. Our recent findings indicate that acute alcohol (EtOH) intoxication exacerbates postburn intestinal and lung tissue damage, and this was found to be neutrophil dependent. Because neutrophil-mediated tissue injury involves the release of superoxide anions (O(2)(-)), the present study examined the role of HO-1 in neutrophil O(2)(-) production following EtOH and burn injury. Furthermore, we investigated whether HO-1 antioxidant properties are mediated via modulation of p47(phox) and/or p67(phox) proteins. Male rats (approximately 250 g) were gavaged with EtOH to achieve a blood EtOH level of approximately 100 mg/dL before burn or sham injury (approximately 12.5% total body surface area). Some rats were treated with HO-1 activator cobalt protoporphyrin IX chloride (Copp; 25 mg/kg body weight) at the time of injury. On day 1 after injury, we found that EtOH combined with burn injury significantly increased neutrophil O(2)(-) production and p47(phox) and p67(phox) activation and decreased caspase-3 activity and apoptosis. This was accompanied with a decrease in neutrophil HO-1 levels. The treatment of animals with HO-1 activator Copp normalized neutrophil HO-1, O(2)(-), p47(phox), and p67(phox) following EtOH and burn injury. The expression of caspase-3, however, was further decreased in Copp-treated sham and EtOH plus burn groups. Moreover, Copp treatment also prevented the increase in intestinal edema and permeability following EtOH and burn injury. Altogether, these findings provide a new insight into the mechanism by which HO-1 regulates neutrophil O(2)(-) production and protect the intestine from damage following EtOH and burn injury.
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Affiliation(s)
- Xiaoling Li
- Center for Surgical Research, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Hu C, Dandapat A, Sun L, Chen J, Marwali MR, Romeo F, Sawamura T, Mehta JL. LOX-1 deletion decreases collagen accumulation in atherosclerotic plaque in low-density lipoprotein receptor knockout mice fed a high-cholesterol diet. Cardiovasc Res 2008; 79:287-93. [PMID: 18453637 DOI: 10.1093/cvr/cvn110] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
AIMS Collagen, as a component of the extracellular matrix, has been linked to atherosclerotic plaque formation and stability. Activation of LOX-1, a lectin-like oxidized low-density lipoprotein (LDL) receptor-1, exerts a significant role in collagen formation. We examine the hypothesis that LOX-1 deletion may inhibit collagen accumulation in atherosclerotic arteries in LDL receptor (LDLR) knockout (KO) mice. METHODS AND RESULTS We generated LOX-1 KO and LOX-1/LDLR double KO mice on a C57BL/6 (wild-type mice) background and fed a 4% cholesterol/10% cocoa butter diet for 18 weeks. Vessel wall collagen accumulation was increased in association with atherogenesis in the LDLR KO mice (P < 0.01 vs. wild-type mice), but much less so in the double KO mice (P < 0.01 vs. LDLR KO mice). Collagen accumulation data were corroborated with pro-collagen I measurements. Expression/activity of osteopontin, fibronectin, and matrix metalloproteinases (MMP-2 and MMP-9) was also increased in the LDLR KO mice (P < 0.01 vs. wild-type mice), but not in the mice with LOX-1 deletion (P < 0.01 vs. LDLR KO mice). The expression of NADPH oxidase (p47(phox), p22(phox), gp91(phox), and Nox-4 subunits) and nitrotyrosine was increased in the LDLR KO mice (P < 0.01 vs. wild-type mice) and not in mice with LOX-1 deletion (P < 0.01 vs. LDLR KO mice). Phosphorylation of Akt-1 and endothelial nitric oxide synthase and expression of haem-oxygenase-1 were found to be reduced in the LDLR KO mice (P < 0.01 vs. wild-type mice), but not in the mice with LOX-1 deletion (P < 0.01 vs. LDLR KO mice). CONCLUSION LOX-1 deletion reduces enhanced collagen deposition and MMP expression in atherosclerotic regions via inhibition of pro-oxidant signals.
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Affiliation(s)
- Changping Hu
- Department of Internal Medicine, Central Arkansas Veterans Healthcare System and University of Arkansas for Medical Sciences, 4301 West Markham Street, Slot 532, Little Rock, AR 72205, USA
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