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Varela-Casariego C, de Haro-Miralles J, Bleda-Moreno S, Esparza-Gómez L, Ferruelo-Alonso A, Acín-García F. El suero de pacientes con enfermedad arterial periférica activa el sistema inmunitario innato a través de los receptores Toll-Like 4 de las células endoteliales. ANGIOLOGIA 2013. [DOI: 10.1016/j.angio.2013.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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52
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Love RJ, Jones KS. The recognition of biomaterials: pattern recognition of medical polymers and their adsorbed biomolecules. J Biomed Mater Res A 2013; 101:2740-52. [PMID: 23613455 DOI: 10.1002/jbm.a.34577] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 01/04/2013] [Indexed: 12/31/2022]
Abstract
All biomedical materials are recognized as foreign entities by the host immune system despite the substantial range of different materials that have been developed by material scientists and engineers. Hydrophobic biomaterials, hydrogels, biomaterials with low protein binding surfaces, and those that readily adsorb a protein layer all seem to incite similar host responses in vivo that may differ in magnitude, but ultimately result in encapsulation by fibrotic tissue. The recognition of medical materials by the host is explained by the very intricate pattern recognition system made up of integrins, toll-like receptors, scavenger receptors, and other surface proteins that enable leukocytes to perceive almost any foreign body. In this review, we describe the various pattern recognition receptors and processes that occur on biomedical material surfaces that permit detection of a range of materials within the host.
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Affiliation(s)
- Ryan J Love
- School of Biomedical Engineering, McMaster University, Hamilton, Ontarion, Canada
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53
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Henderson B, Fares MA, Lund PA. Chaperonin 60: a paradoxical, evolutionarily conserved protein family with multiple moonlighting functions. Biol Rev Camb Philos Soc 2013; 88:955-87. [DOI: 10.1111/brv.12037] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 02/20/2013] [Accepted: 03/04/2013] [Indexed: 02/07/2023]
Affiliation(s)
- Brian Henderson
- Department of Microbial Diseases, UCL-Eastman Dental Institute; University College London; London WC1X 8LD U.K
| | - Mario A. Fares
- Department of Genetics; University of Dublin, Trinity College Dublin; Dublin 2 Ireland
- Department of Abiotic Stress; Instituto de Biologia Molecular y Celular de Plantas, Consejo Superior de Investigaciones Cientificas (CSIC-UPV); Valencia 46022 Spain
| | - Peter A. Lund
- School of Biosciences; University of Birmingham; Birmingham B15 2TT U.K
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Sun J, Ding Y. NOD2 agonist promotes the production of inflammatory cytokines in VSMC in synergy with TLR2 and TLR4 agonists. ScientificWorldJournal 2012; 2012:607157. [PMID: 22997500 PMCID: PMC3446649 DOI: 10.1100/2012/607157] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 08/21/2012] [Indexed: 01/04/2023] Open
Abstract
Objective. To investigate the expression of NOD2 in human VSMCs, its role in the production of inflammatory cytokines in VSMC and the possible interaction of NOD2-mediated signaling pathway with those mediated by TLR2 and TLR4. Methods. Human coronary artery smooth muscle cells were stimulated with NOD2 agonist MDP alone or in combination with either TLR2 agonist PAM3 or TLR4 agonist LPSs. The mRNA expression of NOD2 and FGF-2 were measured by RT-PCR. The concentration of IL-8 and TNF-α in the culture supernatants was determined by ELISA. VSMC proliferation ability was analyzed by MTT assay. Results. MDP up regulated the expression of NOD2 mRNA in VSMC in a time-dependent manner, up regulated the expression of FGF-2 mRNA in VSMC, induced the production of IL-8 and TNF-α, and promoted the proliferation of VSMC. Additionally, MDP synergied with LPS and PAM3 to promote the proliferation of VSMC and induce the production of IL-8 and TNF-α. Conclusion. The activation of NOD2-mediated innate immune signaling pathway can increase the proliferation ability of VSMC and induce the production of inflammatory cytokines in VSMC. It is also shown a synergistic effect with TLR2- and TLR4-mediated signaling pathways in this process.
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Affiliation(s)
- Jinghua Sun
- Department of Oncology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
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Chahine MN, Deniset J, Dibrov E, Hirono S, Blackwood DP, Austria JA, Pierce GN. Oxidized LDL promotes the mitogenic actions of Chlamydia pneumoniae in vascular smooth muscle cells. Cardiovasc Res 2012; 92:476-83. [PMID: 22072707 DOI: 10.1093/cvr/cvr251] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS The atherogenic actions of Chlamydia pneumoniae (C. pneumoniae), a common respiratory pathogen, are dependent upon a high-cholesterol environment in vivo. It is possible that oxidized low-density lipoprotein (oxLDL) is responsible for promoting the atherogenic effects of C. pneumoniae through a stimulation of cell proliferation. This study determined whether oxLDL can enhance the mitogenic action of C. pneumoniae in vascular smooth muscle cells (VSMCs) and the involvement of mitogen-activated protein kinase (MAPK) pathways and heat shock protein 60 (HSP60) in these mechanisms. METHODS AND RESULTS Primary rabbit VSMCs were treated with live C. pneumoniae, heat-inactivated C. pneumoniae or infection medium, and subsequently incubated for up to 48 h in the presence or absence of oxLDL. Chlamydia pneumoniae infection alone stimulated cell proliferation and the addition of oxLDL significantly amplified this proliferative effect. This proliferation was accompanied by extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation and an up-regulation of HSP60 expression. Changes in proliferation and HSP60 expression were attenuated by the inhibition of ERK1/2. CONCLUSION These results indicate a novel role for oxLDL in promoting the mitogenic actions of C. pneumoniae in the vasculature. ERK1/2 is an important factor in the stress-mediated response and HSP60 up-regulation in VSMC. These data provide mechanistic evidence that C. pneumoniae may stimulate atherogenesis.
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Affiliation(s)
- Mirna N Chahine
- Institute of Cardiovascular Sciences, St Boniface Hospital Research Centre, 351 Tache Ave., Winnipeg, Manitoba, Canada R2H 2A6
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56
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Märker T, Sell H, Zilleßen P, Glöde A, Kriebel J, Ouwens DM, Pattyn P, Ruige J, Famulla S, Roden M, Eckel J, Habich C. Heat shock protein 60 as a mediator of adipose tissue inflammation and insulin resistance. Diabetes 2012; 61:615-25. [PMID: 22315307 PMCID: PMC3282817 DOI: 10.2337/db10-1574] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The stress protein heat shock protein 60 (Hsp60) induces secretion of proinflammatory mediators from murine adipocytes. This study aimed to study Hsp60 as a mediator of adipose tissue inflammation and skeletal muscle cell (SkMC) insulin sensitivity and to quantify plasma Hsp60 concentrations in lean and obese individuals. Regulation of Hsp60 release and Hsp60-induced cytokine secretion and signaling was measured in human adipocytes and SkMCs. Adipocytes exhibited higher Hsp60 release than preadipocytes and SkMCs, which was further stimulated by cytokines and Toll-like receptor (TLR)-4 activation. Hsp60 activated extracellular signal-related kinase (ERK)-1/2, Jun NH(2)-terminal kinase (JNK), p38, nuclear factor (NF)-κB, and impaired insulin-stimulated Akt phosphorylation in adipocytes. Furthermore, Hsp60 stimulated adipocytes to secrete tumor necrosis factor-α, interleukin (IL)-6, and IL-8. In SkMCs, Hsp60 activated ERK1/2, JNK, and NF-κB and inhibits insulin signaling and insulin-stimulated glucose uptake. SkMCs released IL-6, IL-8, and monocyte chemoattractant protein-1 on Hsp60 stimulation. Plasma Hsp60 was higher in obese males than in lean males and correlated positively with BMI, blood pressure, leptin, and homeostasis model assessment-insulin resistance. In summary, Hsp60 is released by human adipocytes, increased in plasma of obese humans, and induces insulin resistance. This is accompanied by activation of proinflammatory signaling in human adipocytes and SkMCs. Thus, Hsp60 might be a factor underlying adipose tissue inflammation and obesity-associated metabolic disorders.
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Affiliation(s)
- Tina Märker
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Henrike Sell
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Pia Zilleßen
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anja Glöde
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jennifer Kriebel
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - D. Margriet Ouwens
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Piet Pattyn
- Department of Gastrointestinal Surgery, Ghent University Hospital, Ghent, Belgium
| | - Johannes Ruige
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Susanne Famulla
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- Department of Metabolic Diseases, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jürgen Eckel
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Christiane Habich
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- Corresponding author: Christiane Habich,
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57
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Zhang LL, Gao CY, Fang CQ, Wang YJ, Gao D, Yao GE, Xiang J, Wang JZ, Li JC. PPAR attenuates intimal hyperplasia by inhibiting TLR4-mediated inflammation in vascular smooth muscle cells. Cardiovasc Res 2011; 92:484-493. [DOI: 10.1093/cvr/cvr238] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Toll-like receptor 4 activation in cancer progression and therapy. Clin Dev Immunol 2011; 2011:609579. [PMID: 22110526 PMCID: PMC3216292 DOI: 10.1155/2011/609579] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 09/01/2011] [Indexed: 12/12/2022]
Abstract
Cancer immunotherapy has been the focus of intense research since the late 19th century when Coley observed that bacterial components can contribute to cancer regression by eliciting an antitumor immune response. Successful activation and maturation of tumor-specific immune cells is now known to be mediated by bacterial endotoxin, which activates Toll-like receptor 4 (TLR4). TLR4 is expressed on a variety of immune as well as tumor cells, but its activation can have opposing effects. While TLR4 activation can promote antitumor immunity, it can also result in increased tumor growth and immunosuppression. Nevertheless, TLR4 engagement by endotoxin as well as by endogenous ligands represents notable contribution to the outcome of different cancer treatments, such as radiation or chemotherapy. Further research of the role and mechanisms of TLR4 activation in cancer may provide novel antitumor vaccine adjuvants as well as TLR4 inhibitors that could prevent inflammation-induced carcinogenesis.
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59
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Wisor JP, Clegern WC, Schmidt MA. Toll-like receptor 4 is a regulator of monocyte and electroencephalographic responses to sleep loss. Sleep 2011; 34:1335-45. [PMID: 21966065 DOI: 10.5665/sleep.1274] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
STUDY OBJECTIVES Sleep loss triggers changes in inflammatory signaling pathways in the brain and periphery. The mechanisms that underlie these changes are ill-defined. The Toll-like receptor 4 (TLR4) activates inflammatory signaling cascades in response to endogenous and pathogen-associated ligands known to be elevated in association with sleep loss. TLR4 is therefore a possible mediator of some of the inflammation-related effects of sleep loss. Here we describe the baseline electroencephalographic sleep phenotype and the biochemical and electroencephalographic responses to sleep loss in TLR4-deficient mice. DESIGN, MEASUREMENTS AND RESULTS TLR4-deficient mice and wild type controls were subjected to electroencephalographic and electromyographic recordings during spontaneous sleep/wake cycles and during and after sleep restriction sessions of 3, 6, and 24-h duration, during which sleep was disrupted by an automated sleep restriction system. Relative to wild type control mice, TLR4-deficient mice exhibited an increase in the duration of the primary daily waking bout occurring at dark onset in a light/dark cycle. The amount of time spent in non-rapid eye movement sleep by TLR4-deficient mice was reduced in proportion to increased wakefulness in the hours immediately after dark onset. Subsequent to sleep restriction, EEG measures of increased sleep drive were attenuated in TLR4-deficient mice relative to wild-type mice. TLR4 was enriched 10-fold in brain cells positive for the cell surface marker CD11b (cells of the monocyte lineage) relative to CD11b-negative cells in wild type mouse brains. To assess whether this population was affected selectively by TLR4 knockout, flow cytometry was used to count F4/80- and CD45-positive cells in the brains of sleep deprived and time of day control mice. While wild-type mice exhibited a significant reduction in the number of CD11b-positive cells in the brain after 24-h sleep restriction, TLR4-deficient mice did not. CONCLUSION These data demonstrate that innate immune signaling pathways active in the monocyte lineage, including presumably microglia, detect and mediate in part the cerebral reaction to sleep loss.
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Affiliation(s)
- Jonathan P Wisor
- Department of Veterinary Comparative Anatomy, Pharmacology and Physiology, Sleep and Performance Research Center, Washington State University, Spokane, WA 99210-1945, USA.
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60
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Andrié RP, Bauriedel G, Braun P, Höpp HW, Nickenig G, Skowasch D. Prevalence of intimal heat shock protein 60 homologues in unstable angina and correlation with anti-heat shock protein antibody titers. Basic Res Cardiol 2011; 106:657-65. [PMID: 21416407 DOI: 10.1007/s00395-011-0171-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 02/16/2011] [Accepted: 03/04/2011] [Indexed: 12/21/2022]
Abstract
Heat shock proteins (HSPs) are among the most highly conserved and immunogenic proteins shared by microbial agents and mammals. Human (h) HSP60 is upregulated under stress conditions and serves as a target for cross-reactive cytotoxic HSP-serum-antibodies. The present study evaluates the expressions of hHSP60 and its homologue chlamydial (c) HSP60 in advanced human coronary lesions and correlates intimal tissue-bound HSP expressions with circulating HSP-antibodies. Coronary atherectomy specimens retrieved from 100 primary target lesions of patients with unstable angina (UA; n = 40) or stable angina (SA; n = 60) were assessed immunohistochemically for the presence of hHSP60 and cHSP60. In a subgroup (n = 40), blood samples were tested for anti-Chl. pn.-IgG/IgA-titers and anti-HSP65-antibody titers. Coronary plaques revealed immunoreactive hHSP60 in 55% and cHSP60 in 45% of the lesions. Expression of both HSP homologues was significantly (each p < 0.001) higher in UA lesions compared with SA lesions (7.4 vs. 1.2% and 6.0 vs. 1.1%). HSP homologues showed positive correlations both in UA- and SA-lesions (r = 0.41, 0.33; p < 0.05). cHSP60 showed no association with anti-Chl. pn.-IgG/IgA-titers, whereas expressions of both homologues correlated positive with anti-HSP65-Ab titers (r = 0.42, p < 0.05; r = 0.50, p < 0.01). Intimal amounts of HSP60 homologues were associated with increased expressions of C-reactive protein, Toll-like receptor-4 and tissue factor. Human and chlamydial HSP60 colocalize within coronary atheroma, most prevalent in lesions associated with UA. Our data demonstrate a significant correlation between the intimal expressions of HSP60 homologues and serum HSP65 antibodies, thereby suggesting that humoral immune reactions may play an important role in coronary atherosclerosis and plaque instability.
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Affiliation(s)
- René P Andrié
- Department of Internal Medicine II/Cardiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn, Germany.
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61
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Lin HY, Tang CH, Chen JH, Chuang JY, Huang SM, Tan TW, Lai CH, Lu DY. Peptidoglycan induces interleukin-6 expression through the TLR2 receptor, JNK, c-Jun, and AP-1 pathways in microglia. J Cell Physiol 2011; 226:1573-82. [DOI: 10.1002/jcp.22489] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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62
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Karper JC, de Vries MR, van den Brand BT, Hoefer IE, Fischer JW, Jukema JW, Niessen HWM, Quax PHA. Toll-like receptor 4 is involved in human and mouse vein graft remodeling, and local gene silencing reduces vein graft disease in hypercholesterolemic APOE*3Leiden mice. Arterioscler Thromb Vasc Biol 2011; 31:1033-40. [PMID: 21330606 DOI: 10.1161/atvbaha.111.223271] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The goal of this study was to explore the role of Toll-like receptor 4 (TLR4) in vein graft remodeling and disease. METHODS AND RESULTS First, expression of TLR4 was analyzed in freshly isolated human saphenous veins (huSV), in freshly isolated huSV ex vivo perfused in an extracorporeal circulation, or in huSV used as coronary vein grafts. Marked induction of focal TLR4 expression was observed in perfused fresh huSV. Moreover, TLR4 was abundantly present in lesions in fresh huSV or in intimal hyperplasia in coronary vein grafts. Second, mouse venous bypass grafting was performed. In grafts of hypercholesterolemic APOE*3Leiden mice, increased TLR4 mRNA and protein was detected over time by reverse transcription-polymerase chain reaction and immunohistochemistry. Furthermore, the local presence of the endogenous TLR4 ligands heat shock protein 60, high-mobility group box 1, tenascin-C, and biglycan in the grafts was demonstrated. TLR4 deficiency in C3H-Tlr4LPS-d (LPS indicates lipopolysaccharide) mice resulted in 48±12% less vein graft wall thickening (P=0.04) than in Balb/c controls. Moreover, local TLR4 gene silencing in hypercholesterolemic APOE*3Leiden mice using lentiviral short hairpin RNA against TLR4 administered perivascularly around vein grafts led to a 44±13% reduction of vessel wall thickening compared with controls (P=0.0059). CONCLUSIONS These results indicate that TLR4 is involved in vein graft remodeling and can be used as a local therapeutic target against vein graft disease.
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Affiliation(s)
- Jacco C Karper
- Department of Vascular Surgery, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, the Netherlands
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63
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Su X, Ao L, Shi Y, Johnson TR, Fullerton DA, Meng X. Oxidized low density lipoprotein induces bone morphogenetic protein-2 in coronary artery endothelial cells via Toll-like receptors 2 and 4. J Biol Chem 2011; 286:12213-20. [PMID: 21325271 DOI: 10.1074/jbc.m110.214619] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Vascular calcification is a common complication in atherosclerosis. Bone morphogenetic protein-2 (BMP-2) plays an important role in atherosclerotic vascular calcification. The aim of this study was to determine the effect of oxidized low density lipoprotein (oxLDL) on BMP-2 protein expression in human coronary artery endothelial cells (CAECs), the roles of Toll-like receptor (TLR) 2 and TLR4 in oxLDL-induced BMP-2 expression, and the signaling pathways involved. Human CAECs were stimulated with oxLDL. The roles of TLR2 and TLR4 in oxLDL-induced BMP-2 expression were determined by pretreatment with neutralizing antibody, siRNA, and overexpression. Stimulation with oxLDL increased cellular BMP-2 protein levels in a dose-dependent manner (40-160 μg/ml). Pretreatment with neutralizing antibodies against TLR2 and TLR4 or silencing of these two receptors reduced oxLDL-induced BMP-2 expression. Overexpression of TLR2 and TLR4 enhanced the cellular BMP-2 response to oxLDL. Furthermore, oxLDL was co-localized with TLR2 and TLR4. BMP-2 expression was associated with activation of nuclear factor-κB (NF-κB), p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase (ERK)1/2. Inhibition of NF-κB and ERK1/2 reduced BMP-2 expression whereas inhibition of p38 MAPK had no effect. In conclusion, oxLDL induces BMP-2 expression through TLR2 and TLR4 in human CAECs. The NF-κB and ERK1/2 pathways are involved in the signaling mechanism. These findings underscore an important role for TLR2 and TLR4 in mediating the BMP-2 response to oxLDL in human CAECs and indicate that these two immunoreceptors contribute to the mechanisms underlying atherosclerotic vascular calcification.
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Affiliation(s)
- Xin Su
- Department of Surgery, University of Colorado Denver, Aurora, Colorado 80045, USA
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64
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Ye HH, Zhang YM. Advances in understanding the relationship between Toll-like receptors and digestive system injury. Shijie Huaren Xiaohua Zazhi 2010; 18:2339-2345. [DOI: 10.11569/wcjd.v18.i22.2339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Toll-like receptors (TLRs) are cell-surface molecules that play an important role in the host immune response. More and more evidence indicates that TLRs can recognize special pattern molecules to activate certain signal transduction pathways and result in the release of numerous inflammatory mediators and active substances to induce digestive system injury, such as Helicobacter pylori infection-induced gastric mucosal injury, alcohol-induced gastritis, alcohol-induced liver injury, acute hemorrhagic necrotizing pancreatitis, hepatic ischemia-reperfusion injury (I/RI), and dextran sodium sulfate (DSS)-induced colitis. Here, we review the advances in understanding the relationship between TLRs and digestive system injury and explore the clinical value of TLRs in the diagnosis and treatment of digestive system diseases.
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65
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DAMPening inflammation by modulating TLR signalling. Mediators Inflamm 2010; 2010. [PMID: 20706656 PMCID: PMC2913853 DOI: 10.1155/2010/672395] [Citation(s) in RCA: 652] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2009] [Accepted: 04/20/2010] [Indexed: 12/12/2022] Open
Abstract
Damage-associated molecular patterns (DAMPs) include endogenous intracellular molecules released by activated or necrotic cells and extracellular matrix (ECM) molecules that are upregulated upon injury or degraded following tissue damage. DAMPs are vital danger signals that alert our immune system to tissue damage upon both infectious and sterile insult. DAMP activation of Toll-like receptors (TLRs) induces inflammatory gene expression to mediate tissue repair. However, DAMPs have also been implicated in diseases where excessive inflammation plays a key role in pathogenesis, including rheumatoid arthritis (RA), cancer, and atherosclerosis. TLR activation by DAMPs may initiate positive feedback loops where increasing tissue damage perpetuates pro-inflammatory responses leading to chronic inflammation. Here we explore the current knowledge about distinct signalling cascades resulting from self TLR activation. We also discuss the involvement of endogenous TLR activators in disease and highlight how specifically targeting DAMPs may yield therapies that do not globally suppress the immune system.
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66
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Pulskens WP, Rampanelli E, Teske GJ, Butter LM, Claessen N, Luirink IK, van der Poll T, Florquin S, Leemans JC. TLR4 promotes fibrosis but attenuates tubular damage in progressive renal injury. J Am Soc Nephrol 2010; 21:1299-308. [PMID: 20595685 DOI: 10.1681/asn.2009070722] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Toll-like receptors (TLRs) can orchestrate an inflammatory response upon activation by pathogen-associated motifs and release of endogenous stress ligands during tissue injury. The kidney constitutively expresses most TLRs, including TLR4. The function of TLR4 during the inflammation, tubular atrophy, and fibrosis that accompany progressive renal injury is unknown. Here, we subjected wild-type (WT) and TLR4-deficient mice to unilateral ureteral obstruction and observed elevated levels of TLR4 mRNA in the kidney after obstruction. One day after unilateral ureteral obstruction, TLR4-deficient mice had fewer proliferating tubular epithelial cells and more tubular damage than WT mice; however, TLR4-deficient mice developed considerably less renal fibrosis despite decreased matrix metalloproteinase activity and without significant differences in myofibroblast accumulation. In vitro, TLR4-deficient primary tubular epithelial cells and myofibroblasts produced significantly less type I collagen mRNA after TGF-beta stimulation than WT cells. The reduced fibrosis in TLR4-deficient mice associated with an upregulation of Bambi, a negative regulator of TGF-beta signaling. In conclusion, TLR4 attenuates tubular damage but promotes renal fibrosis by modulating the susceptibility of renal cells to TGF-beta. These data suggest that TLR4 signaling may be a therapeutic target for the prevention of renal fibrosis.
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Affiliation(s)
- Wilco P Pulskens
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.
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67
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The expression and functions of toll-like receptors in atherosclerosis. Mediators Inflamm 2010; 2010:393946. [PMID: 20652007 PMCID: PMC2905957 DOI: 10.1155/2010/393946] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 04/07/2010] [Indexed: 12/16/2022] Open
Abstract
Inflammation drives atherosclerosis. Both immune and resident vascular cell types are involved in the development of atherosclerotic lesions. The phenotype and function of these cells are key in determining the development of lesions. Toll-like receptors are the most characterised innate immune receptors and are responsible for the recognition of exogenous conserved motifs on pathogens, and, potentially, some endogenous molecules. Both endogenous and exogenous TLR agonists may be present in atherosclerotic plaques. Engagement of toll-like receptors on immune and resident vascular cells can affect atherogenesis as signalling downstream of these receptors can elicit proinflammatory cytokine release, lipid uptake, and foam cell formation and activate cells of the adaptive immune system. In this paper, we will describe the expression of TLRs on immune and resident vascular cells, highlight the TLR ligands that may act through TLRs on these cells, and discuss the consequences of TLR activation in atherosclerosis.
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68
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King AE, Critchley HOD. Oestrogen and progesterone regulation of inflammatory processes in the human endometrium. J Steroid Biochem Mol Biol 2010; 120:116-26. [PMID: 20067835 DOI: 10.1016/j.jsbmb.2010.01.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 12/23/2009] [Accepted: 01/05/2010] [Indexed: 01/14/2023]
Abstract
The human endometrium is a unique tissue that has to undergo cycles of proliferation, differentiation, destruction and repair. This ensures that the endometrium is optimally prepared for potential embryo implantation but in the absence of an embryo, menstruation occurs to allow endometrial regeneration. These cycles of tissue remodelling occur under the sequential influence of the sex steroid hormones, oestrogen and progesterone. The physiological events of implantation and menstruation display features of inflammation, tightly regulated by oestrogen and progesterone. After menstruation cellular proliferation and blood vessel growth is modulated by oestrogen while after ovulation progesterone is the dominant hormone. In preparation for implantation, progesterone regulates decidualization of the endometrium, uterine natural killer cell numbers within the endometrium and chemokine and cytokine expression. Menstruation, in contrast, is preceded by progesterone withdrawal, which results in an influx of leukocytes into the endometrium and increased production of chemokines and matrix metalloproteinases allowing tissue degradation. The aim of this article is to review the current knowledge on the regulation of inflammatory events within the endometrium by oestrogen and progesterone, in relation to two pivotal events for human reproduction, implantation and menstruation.
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Affiliation(s)
- Anne E King
- University of Edinburgh, Centre for Reproductive Biology, The Queen's Medical Research Institute, United Kingdom
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69
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Gill R, Tsung A, Billiar T. Linking oxidative stress to inflammation: Toll-like receptors. Free Radic Biol Med 2010; 48:1121-32. [PMID: 20083193 PMCID: PMC3423196 DOI: 10.1016/j.freeradbiomed.2010.01.006] [Citation(s) in RCA: 406] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2009] [Revised: 01/01/2010] [Accepted: 01/05/2010] [Indexed: 02/06/2023]
Abstract
Injury caused by oxidative stress occurs in many clinical scenarios involving ischemia and reperfusion such as organ transplantation, hemorrhagic shock (HS), myocardial infarction, and cerebral vascular accidents. Activation of the immune system as a result of disturbances in the redox state of cells seems to contribute to tissue and organ damage in these conditions. The link between oxidative stress and inflammatory pathways is poorly understood. Recently, Toll-like receptors (TLRs) have been shown to mediate the inflammatory response seen in experimental ischemia and reperfusion (I/R). The TLR family of receptors involved in alerting the innate immune system of danger seems to be activated by damage-associated molecular pattern molecules (DAMPs) that are released during conditions of oxidative stress. In this review, we examine the role of TLRs in various experimental models of oxidative stress such as HS and I/R. We also report on potential DAMPs that may interact with TLRs in mediating injury. Finally, potential mechanisms by which reactive oxygen species from NADPH oxidase can signal the commencement of inflammatory pathways through TLRs are explored.
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Affiliation(s)
- Roop Gill
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA.
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70
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Abstract
The mammalian TLRs serve as key sensors of PAMPs, such as bacterial LPS, lipopeptides, and flagellins, which are present in microbial cells but not host cells. TLRs have therefore been considered to play a central role in the discrimination between "self" and "non-self". However, since the discovery of their microbial ligands, many studies have provided evidence that host-derived molecules may also stimulate TLR2- or TLR4-dependent signaling. To date, more than 20 of these endogenous TLR ligands have been proposed, which have tended to fall into the categories of released intracellular proteins, ECM components, oxidatively modified lipids, and other soluble mediators. This review aims to summarize the evidence supporting the intrinsic TLR-stimulating capacity of each of these proposed endogenous ligands with a particular emphasis on the measures taken to exclude contaminating LPS and lipopeptides from experimental systems. The emerging evidence that many of these molecules may be more accurately described as PAMP-binding molecules (PBMs) or PAMP-sensitizing molecules (PSMs), rather than genuine ligands of TLR2 or TLR4, is also summarized. The relevance of this possibility to the pathogenesis of chronic inflammatory diseases, tumor surveillance, and autoimmunity is discussed.
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Affiliation(s)
- Clett Erridge
- Department of Cardiovascular Sciences, Glenfield General Hospital, University of Leicester, Leicester, UK, LE3 9QP.
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71
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Knowlton AA, Srivatsa U. Heat-shock protein 60 and cardiovascular disease: a paradoxical role. Future Cardiol 2009; 4:151-61. [PMID: 19804293 DOI: 10.2217/14796678.4.2.151] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Heat-shock proteins (HSPs) are members of a highly conserved group of proteins that are induced in response to stress and injury. These proteins have protective properties, and can protect the heart from injury. HSP60 is found in the mitochondria and cytosol, and has essential intracellular functions including folding key proteins after their import into the mitochondria. In the cytosol, HSP60 binds to proapoptotic proteins, sequestering them. HSPs are highly conserved and, thus, are similar to bacterial proteins. Many individuals have antibodies to HSP60, possibly from prior infections. HSP60 can be found in the plasma membrane and in the serum in disease states. Serum HSP60 may be a marker for coronary artery disease. Once extracellular, HSP60 can cause cell injury. Thus, this protein has dichotomous functions for which the role in disease remains to be fully elucidated.
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Affiliation(s)
- Anne A Knowlton
- University of California, Molecular & Cellular Cardiology, Davis One Shields Avenue, Davis, CA 95616, USA, and Department of Veterans Affairs, Northern california Health Care System, Mather, CA, USA.
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72
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Kim SC, Stice JP, Chen L, Jung JS, Gupta S, Wang Y, Baumgarten G, Trial J, Knowlton AA. Extracellular heat shock protein 60, cardiac myocytes, and apoptosis. Circ Res 2009; 105:1186-95. [PMID: 19875724 DOI: 10.1161/circresaha.109.209643] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
RATIONALE Previously, we have found that changes in the location of intracellular heat shock protein (HSP)60 are associated with apoptosis. HSP60 has been reported to be a ligand of toll-like receptor (TLR)-4. OBJECTIVE We hypothesized that extracellular HSP60 (exHSP60) would mediate apoptosis via TLR4. METHODS AND RESULTS Adult rat cardiac myocytes were treated with HSP60, either recombinant human or with HSP60 purified from the media of injured rat cardiac myocytes. ExHSP60 induced apoptosis in cardiac myocytes, as detected by increased caspase 3 activity and increased DNA fragmentation. Apoptosis could be reduced by blocking antibodies to TLR4 and by nuclear factor kappaB binding decoys, but not completely inhibited, even though similar treatment blocked lipopolysaccharide-induced apoptosis. Three distinct controls showed no evidence for involvement of a ligand other than exHSP60 in the mediation of apoptosis. CONCLUSIONS This is the first report of HSP60-induced apoptosis via the TLRs. HSP60-mediated activation of TLR4 may be a mechanism of myocyte loss in heart failure, where HSP60 has been detected in the plasma.
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Affiliation(s)
- Se-Chan Kim
- Molecular & Cellular Cardiology, University of California-Davis, One Shields Ave, Davis, CA 95616, USA
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73
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Hurley NE, Schildmeyer LA, Bosworth KA, Sakurai Y, Eskin SG, Hurley LH, McIntire LV. Modulating the functional contributions of c-Myc to the human endothelial cell cyclic strain response. J Vasc Res 2009; 47:80-90. [PMID: 19729955 PMCID: PMC2855285 DOI: 10.1159/000235928] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2008] [Accepted: 02/03/2009] [Indexed: 11/19/2022] Open
Abstract
This study addresses whether pathological levels of cyclic strain activate the c-Myc promoter, leading to c-Myc transcription and downstream gene induction in human umbilical vein endothelial cells (HUVEC) or human aortic endothelial cells (HAEC). mRNA and protein expression of c-Myc under physiological (6-10%) and pathological cyclic strain conditions (20%) were studied. Both c-Myc mRNA and protein expression increased 2-3-fold in HUVEC cyclically strained at 20%. c-Myc protein increased 4-fold in HAEC. In HUVEC, expression of mRNA peaked at 1.5-2 h. Subsequently, the effect of modulating c-Myc on potential downstream gene targets was determined. A small molecular weight compound that binds to and stabilizes the silencer element in the c-Myc promoter attenuates cyclic strain-induced c-Myc transcription by about 50%. This compound also modulates c-Myc downstream gene targets that may be instrumental in induction of vascular disease. Cyclic strain-induced gene expression of vascular endothelial growth factor, proliferating cell nuclear antigen and heat shock protein 60 are attenuated by this compound. These results offer a possible mechanism and promising clinical treatment for vascular diseases initiated by increased cyclic strain.
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Affiliation(s)
- Nicole E. Hurley
- Bioengineering Program, Georgia Institute of Technology, Atlanta, Ga., USA
| | - Lisa A. Schildmeyer
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Ga., USA
| | - Kami A. Bosworth
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Ga., USA
| | - Yumiko Sakurai
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Ga., USA
| | - Suzanne G. Eskin
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Ga., USA
| | | | - Larry V. McIntire
- Bioengineering Program, Georgia Institute of Technology, Atlanta, Ga., USA
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Ga., USA
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74
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King AE, Horne AW, Hombach-Klonisch S, Mason JI, Critchley HOD. Differential expression and regulation of nuclear oligomerization domain proteins NOD1 and NOD2 in human endometrium: a potential role in innate immune protection and menstruation. Mol Hum Reprod 2009; 15:311-9. [PMID: 19273470 DOI: 10.1093/molehr/gap020] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nuclear oligomerization domains (NODs) are cytosolic pattern recognition receptors (PRRs), present in epithelial cells, monocytes and dendritic cells. This study details their expression, regulation and role in human endometrium. Real-time PCR showed that NOD1 mRNA is constitutively expressed in endometrium. NOD2 is up-regulated in the late secretory phase of the menstrual cycle suggesting a role in menstruation. Both proteins are immunolocalized in endometrial epithelium, stroma and endothelium. In first trimester, decidua NODs are present in decidualized stroma. NOD function was examined in endometrial stromal cells (ESCs) and endometrial epithelial cells (EEpCs) in vitro. IkappaBalpha is up-regulated by stimulation of ESC and EEpC with an NOD1 ligand. IkappaBalpha, IL-8 and TNFalpha mRNA expression is increased in EEpC by a NOD2 ligand. NOD2 mRNA expression increases in response to IL-1 treatment while NOD1 transcripts are unaltered. NOD1 mRNA is increased in an in vitro model of decidualization of ESC. In summary, we report expression of NOD1 and NOD2 in human endometrium and show that they are differentially regulated. NOD2 and, to a lesser extent, NOD1 can function to increase expression of innate immune molecules in endometrium. NODs may have a role in innate immune protection in the uterus and NOD2 may regulate inflammation associated with menstruation.
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Affiliation(s)
- Anne E King
- Reproductive and Developmental Sciences, Centre for Reproductive Biology, The Queen's Medical Research Institute, Edinburgh, UK.
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75
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Kern JM, Maass V, Maass M. Chlamydia pneumoniae-induced pathological signaling in the vasculature. ACTA ACUST UNITED AC 2009; 55:131-9. [DOI: 10.1111/j.1574-695x.2008.00514.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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76
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Pulskens WP, Teske GJ, Butter LM, Roelofs JJ, van der Poll T, Florquin S, Leemans JC. Toll-like receptor-4 coordinates the innate immune response of the kidney to renal ischemia/reperfusion injury. PLoS One 2008; 3:e3596. [PMID: 18974879 PMCID: PMC2570789 DOI: 10.1371/journal.pone.0003596] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 09/25/2008] [Indexed: 12/24/2022] Open
Abstract
Toll-like receptors (TLRs) can detect endogenous danger molecules released upon tissue injury resulting in the induction of a proinflammatory response. One of the TLR family members, TLR4, is constitutively expressed at RNA level on renal epithelium and this expression is enhanced upon renal ischemia/reperfusion (I/R) injury. The functional relevance of this organ-specific upregulation remains however unknown. We therefore investigated the specific role of TLR4 and the relative contribution of its two downstream signaling cascades, the MyD88-dependent and TRIF-dependent cascades in renal damage by using TLR4−/−, MyD88−/− and TRIF-mutant mice that were subjected to renal ischemia/reperfusion injury. Our results show that TLR4 initiates an exaggerated proinflammatory response upon I/R injury, as reflected by lower levels of chemokines and infiltrating granulocytes, less renal damage and a more preserved renal function in TLR4−/− mice as compared to wild type mice. In vitro studies demonstrate that renal tubular epithelial cells can coordinate an immune response to ischemic injury in a TLR4-dependent manner. In vivo we found that epithelial- and leukocyte-associated functional TLR4 contribute in a similar proportion to renal dysfunction and injury as assessed by bone marrow chimeric mice. Surprisingly, no significant differences were found in renal function and inflammation in MyD88−/− and TRIF-mutant mice compared with their wild types, suggesting that selective targeting of TLR4 directly may be more effective for the development of therapeutic tools to prevent I/R injury than targeting the intracellular pathways used by TLR4. In conclusion, we identified TLR4 as a cellular sentinel for acute renal damage that subsequently controls the induction of an innate immune response.
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Affiliation(s)
- Wilco P Pulskens
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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77
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Antigen-induced immunomodulation in the pathogenesis of atherosclerosis. Clin Dev Immunol 2008; 2008:723539. [PMID: 18551190 PMCID: PMC2423423 DOI: 10.1155/2008/723539] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 04/02/2008] [Accepted: 04/30/2008] [Indexed: 12/16/2022]
Abstract
Atherosclerosis is a chronic inflammatory disorder characterised by the accumulation of monocytes/macrophages, smooth muscle cells, and lymphocytes within the arterial wall in response to the release of proinflammatory molecules. Such accumulation results in the formation of the atherosclerotic plaque, which would eventually evolve to complications such as total artery occlusion, rupture, calcification, or aneurysm. Although the molecular mechanism responsible for the development of atherosclerosis is not completely understood, it is clear that the immune system plays a key role in the development of the atherosclerotic plaque and in its complications. There are multiple antigenic stimuli that have been associated with the pathogenesis of atherosclerosis. Most of these stimuli come from modified self-molecules such as oxidised low-density lipoproteins (oxLDLs), beta2glycoprotein1 (β2GP1), lipoprotein a (LP(a)), heat shock proteins (HSPs), and protein components of the extracellular matrix such as collagen and fibrinogen in the form of advanced glycation-end (AGE) products. In addition, several foreign antigens including bacteria such as Porphyromonas gingivalis and Chlamydia pneumoniae and viruses such as enterovirus and cytomegalovirus have been associated with atherosclerosis as potentially causative or bystander participants, adding another level of complexity to the analysis of the pathophysiology of atherosclerosis. The present review summarises the most important scientific findings published within the last two decades on the importance of antigens, antigen stimulation, and adaptive immune responses in the development of atherosclerotic plaques.
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78
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Huang B, Chen H, Fan M. Inhibition of TLR4 signaling pathway: Molecular treatment strategy of periodontitis-associated atherosclerosis. Med Hypotheses 2008; 70:614-7. [PMID: 17681703 DOI: 10.1016/j.mehy.2007.06.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Accepted: 06/07/2007] [Indexed: 11/30/2022]
Abstract
The accumulation of epidemiologic, pathologic, and animal model studies suggests that periodontal infection may be a contributing risk factor for atherosclerosis. The Toll-like receptor-4 (TLR4) signaling pathway plays an important role in the initiation and progression of periodontitis-associated atherosclerotic disease. We postulate that suppression of TLR4 signaling pathway can be an effective treatment for atherosclerosis. These strategies include prevention of ligand binding to TLR4, blocking the interactions of TLR4s and adaptors in signaling pathways, blocking the enzymes in signaling pathways, and immunostimulation with vaccine adjuvants. However, we should be aware that there may be unknown risks about the new technologies and these drugs, which may cause some unknown side effects in long-term administration.
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Affiliation(s)
- Bin Huang
- Department of Stomatology, Xianning College, Xianning 437100, PR China.
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79
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Kloppenburg GTL, de Graaf R, Grauls GELM, Bruggeman CA, Stassen FR. Chlamydia pneumoniae aggravates vein graft intimal hyperplasia in a rat model. BMC Microbiol 2007; 7:111. [PMID: 18062811 PMCID: PMC2222630 DOI: 10.1186/1471-2180-7-111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Accepted: 12/06/2007] [Indexed: 11/29/2022] Open
Abstract
Background Along with angioplasty, autologus vein grafts are commonly used for artery bypass grafting in patients with advanced arterial stenosis and drug-resistant angina pectoris. Although initially a successful procedure, long-term functionality is limited due to proliferation and migration of smooth muscle cells. Like in atherosclerosis, common chronic infections caused by viruses and bacteria may contribute to this process of vein graft failure. Here we investigated the possible role of Chlamydia pneumoniae (Cpn) in the pathogenesis of venous graft failure in an experimental animal model. In 2 groups (n = 10 rats/group), an epigastric vein-to-common femoral artery interposition graft was placed. Immediately thereafter, rats were infected with Cpn (5*108 IFU) or injected with control solutions. Rats were sacrificed three weeks after surgery and the grafts were harvested for morphometrical and immunohistochemical analysis. Results Cpn administration immediately after vein grafting resulted in a significant increase in medial cross-sectional area, wall thickness and total wall area. There were no significant differences in T-cell or macrophage influx. Likewise, although positive immunostaining for both HSP60 and CRP could be detected, no differences were found between groups. Based on the observation that the number of cells/μm2 was also not altered, we conclude that Cpn infection stimulates smooth muscle cell proliferation by hereunto unknown molecular mechanisms, resulting in a significant increase in intimal hyperplasia. Conclusion In conclusion, in a well defined animal model we present here for the first time evidence for a role of Chlamydia pneumoniae in the process of venous graft failure.
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Affiliation(s)
- Geoffrey T L Kloppenburg
- Cardiovascular Research Institute Maastricht, Department of Medical Microbiology, Academic Hospital Maastricht/Maastricht University, Maastricht, MD Maastricht, The Netherlands.
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Chaperonin 10 as a putative modulator of multiple Toll-like receptors for the treatment of inflammatory diseases. Expert Opin Ther Pat 2007. [DOI: 10.1517/13543776.17.10.1299] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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81
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Abstract
Toll-like receptors (TLRs) are pivotal in human response to microbial stimuli. Their activation and signaling underpin much of the observed epidemiologic data generated by the hygiene hypothesis, and their contribution to infectious exacerbations of airways disease is likely to be highly important. Our growing knowledge in this field will have a significant impact on the understanding of the pathogenesis of inflammatory diseases, and TLR-based therapies are already in early clinical trials to modify atopic disease severity.
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Affiliation(s)
- Nazia Chaudhuri
- Academic Unit of Respiratory Medicine, School of Medicine and Biomedical Sciences, University of Sheffield, L Floor, Royal Hallamshire Hospital, Sheffield, UK
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Lunardi C, Dolcino M, Peterlana D, Bason C, Navone R, Tamassia N, Tinazzi E, Beri R, Corrocher R, Puccetti A. Endothelial cells' activation and apoptosis induced by a subset of antibodies against human cytomegalovirus: relevance to the pathogenesis of atherosclerosis. PLoS One 2007; 2:e473. [PMID: 17534423 PMCID: PMC1868596 DOI: 10.1371/journal.pone.0000473] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2007] [Accepted: 05/02/2007] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Human cytomegalovirus (hCMV) is involved in the pathogenesis of atherosclerosis. We have previously shown in patients with atherosclerosis that antibodies directed against the hCMV-derived proteins US28 and UL122 are able to induce endothelial cell damage and apoptosis of non-stressed endothelial cells through cross-rection with normally expressed surface molecules. Our aim was to dissect the molecular basis of such interaction and to investigate mechanisms linking innate immunity to atherosclerosis. METHODOLOGY/PRINCIPAL FINDINGS We analysed the gene expression profiles in endothelial cells stimulated with antibodies affinity-purified against either the UL122 or the US28 peptides using the microarray technology. Microarray results were validated by quantitative PCR and by detection of proteins in the medium. Supernatant of endothelial cells incubated with antibodies was analysed also for the presence of Heat Shock Protein (HSP)60 and was used to assess stimulation of Toll-Like Receptor-4 (TLR4). Antibodies against UL122 and US28 induced the expression of genes encoding for adhesion molecules, chemokines, growth factors and molecules involved in the apoptotis process together with other genes known to be involved in the initiation and progression of the atherosclerotic process. HSP60 was released in the medium of cells incubated with anti-US28 antibodies and was able to engage TLR4. CONCLUSIONS/SIGNIFICANCE Antibodies directed against hCMV modulate the expression of genes coding for molecules involved in activation and apoptosis of endothelial cells, processes known to play a pivotal role in the pathogenesis of atherosclerosis. Moreover, endothelial cells exposed to such antibodies express HSP60 on the cell surface and release HSP60 in the medium able to activate TLR4. These data confirm that antibodies directed against hCMV-derived proteins US28 and UL122 purified from patients with coronary artery disease induce endothelial cell damage and support the hypothesis that hCMV infection may play a crucial role in mediating the atherosclerotic process.
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Affiliation(s)
- Claudio Lunardi
- Department of Clinical and Experimental Medicine, Section of Internal Medicine, University of Verona, Verona, Italy.
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