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Cytokines Tumor Necrosis Factor (cytokine + tumor_necrosis_factor)
Kinds of Cytokines Tumor Necrosis Factor Selected AbstractsTumor necrosis factor-alpha (TNF-,) regulates Toll-like receptor 2 (TLR2) expression in microgliaJOURNAL OF NEUROCHEMISTRY, Issue 4 2007Mohsin Md. Abstract Microglia represent one effector arm of CNS innate immunity as evident by their role in pathogen recognition. We previously reported that exposure of microglia to Staphylococcus aureus (S. aureus), a prevalent CNS pathogen, led to elevated Toll-like receptor 2 (TLR2) expression, a pattern recognition receptor capable of recognizing conserved structural motifs associated with gram-positive bacteria such as S. aureus. In this study, we demonstrate that the proinflammatory cytokine tumor necrosis factor-, (TNF-,) enhances TLR2 expression in microglia, whereas interleukin-1, has no significant effect. To determine the downstream signaling events responsible for elevated microglial TLR2 expression in response to TNF-,, a series of signal transduction inhibitors were employed. Treatment with caffeic acid phenethyl ester, an inhibitor of redox-mediated nuclear factor-kappa B activation, significantly attenuated TNF-,-induced TLR2 expression. Similar results were observed with the IKK-2 and I,B-, inhibitors SC-514 and BAY 11-7082, respectively. In contrast, no significant alterations in TLR2 expression were observed with protein kinase C or p38 mitogen-activated protein kinase inhibitors. A definitive role for TNF-, was demonstrated by the inability of S. aureus to augment TLR2 expression in microglia isolated from TNF-, knockout mice. In addition, TLR2 expression was significantly attenuated in brain abscesses of TNF-, knockout mice. Collectively, these results indicate that in response to S. aureus, TNF-, acts in an autocrine/paracrine manner to enhance TLR2 expression in microglia and that this effect is mediated, in part, by activation of the nuclear factor-kappa B pathway. [source] NFATc1 and TNF, expression in giant cell lesions of the jawsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 3 2010Fabrício Rezende Amaral J Oral Pathol Med (2010) 39: 269,274 Background:, Activation mutations of SH3BP2 gene have been demonstrated in cherubism and central giant cell lesion (CGCL). In the present study we first attempted to investigate the SH3BP2 gene in peripheral giant cell lesion (PGCL). The effect of SH3BP2 gene mutations on the transcription of the downstream genes nuclear factor of activated T cells (NFATc1) and the cytokine tumor necrosis factor-, (TNF-,) was also investigated together with the immunolocalization of NFATc1 protein in a set of cases of PGCL, CGCL and cherubism with and without SH3BP2 mutation. Method:, Fresh samples of five PGCL, five CGCL and one cherubism cases were included in this study. One of the samples of CGCL presented a somatic heterozygous mutation c.1442A>T in exon 11. The cherubism case showed a heterozygotic substitution c.320C>T in both blood and lesion. These mutations were previously published. All coding and flanking regions of the SH3BP2 gene were sequenced in the cases of PGCL. The real-time polymerase chain reaction (RT-PCR) was performed to analyze the transcription of NFATc1 and TNF-, genes. The immunohistochemical analysis of the NFATc1 protein was also performed. Results:, No SH3BP2 gene mutation was found in PGCL. The RT-PCR showed increased expression of NFATc1 and decreased transcription of TNF-, in all the samples. The immunohistochemical analysis of the NFATc1 protein showed a predominant nuclear staining in the multinucleated giant cells. Conclusion:, The development of giant cells lesions of the jaws and cherubism are possibly mediated by overexpression of NFAT in the nucleus of the multinucleated cells. [source] Dysregulated Cytokine Metabolism, Altered Hepatic Methionine Metabolism and Proteasome Dysfunction in Alcoholic Liver DiseaseALCOHOLISM, Issue 2005Craig McClain Abstract: Alcoholic liver disease (ALD) remains an important complication and cause of morbidity and mortality from alcohol abuse. Major developments in our understanding of the mechanisms of ALD over the past decade are now being translated into new forms of therapy for this disease process which currently has no FDA approved treatment. Cytokines are low molecular weight mediators of cellular communication, and the pro-inflammatory cytokine tumor necrosis factor (TNF) has been shown to play a pivotal role in the development of experimental ALD. Similarly, TNF levels are elevated in the serum of alcoholic hepatitis patients. Abnormal methionine metabolism is well documented in patients with ALD, with patients having elevated serum methionine levels, but low S-adenosylmethionine levels in the liver. On the other hand, S-adenosylhomocysteine and homocysteine levels are elevated in ALD. Recent studies have documented potential interactions between homocysteine and S-adenosylhomocysteine with TNF in the development of ALD. Altered proteasome function also is now well documented in ALD, and decreased proteasome function can cause hepatocyte apoptosis. Recently it has been shown that decreased proteasome function can also act synergistically to enhance TNF hepatotoxicity. Hepatocytes dying of proteasome dysfunction release pro-inflammatory cytokines such as Interleukin-8 to cause sustained inflammation. This article reviews the interactions of cytokines, altered methionine metabolism, and proteasome dysfunction in the development of ALD. [source] Spinal tumor necrosis factor , neutralization reduces peripheral inflammation and hyperalgesia and suppresses autonomic responses in experimental arthritis: A role for spinal tumor necrosis factor , during induction and maintenance of peripheral inflammationARTHRITIS & RHEUMATISM, Issue 5 2010Michael Karl Boettger Objective In addition to the sensitization of pain fibers in inflamed tissues, the increased excitability of the spinal cord is an important mechanism of inflammatory pain. Furthermore, spinal neuronal excitability has been suggested to play a role in modulating peripheral inflammation. This study was undertaken to test the hypothesis that spinal actions of the proinflammatory cytokine tumor necrosis factor , (TNF,) add significantly to both hyperalgesia and maintenance of peripheral inflammation. Methods Rats with antigen-induced arthritis (AIA) were treated intrathecally with the TNF,-neutralizing compound etanercept continuously during the complete time course of AIA, which was 3 days for the acute phase and 21 days for the chronic phase. During this time, inflammation and pain-related behavior were monitored. Since a role for autonomic control of inflammation was proposed, measures from heart rate time series were obtained in the acute phase. Findings were compared with those in vehicle-treated animals and in animals receiving etanercept intraperitoneally. Results Spinally administered etanercept acutely reduced pain-related behavior, attenuated both the development and the maintenance of inflammation, and was superior to systemic administration. Parameters indicating autonomic modulation showed a shift toward a sympathetically dominated state in vehicle-treated animals, which was prevented by intrathecal etanercept. Conclusion Our findings indicate that spinal TNF, plays an important role in both pain signaling and modulation of peripheral inflammation. Thus, neutralizing this cytokine at the spinal site not only represents a putative therapeutic option for different pain syndromes, but may be directly used to attenuate peripheral inflammation. [source] CCL28 production in HaCaT cells was mediated by different signal pathways from CCL27EXPERIMENTAL DERMATOLOGY, Issue 2 2006Shinji Kagami Abstract:, Both CCL27 and CCL28 are ligands for CCR10 and attract CCR10+ lymphocytes. We previously demonstrated that CCL27 and CCL28 were strongly expressed in sera and lesional keratinocytes of patients with atopic dermatitis and psoriasis vulgaris. However, the regulation of CCL27 and CCL28 production in keratinocytes has not been well documented. In this study, we showed that CCL27 and CCL28 expression and production by a human keratinocyte cell line, HaCaT cells, were strongly induced by inflammatory cytokines tumor necrosis factor-, and interleukin-1,. CCL27 production was downregulated by inhibitors of p38 mitogen-activated protein kinase and nuclear factor-kappa B (NF-,B). By contrast, CCL28 production was downregulated by inhibitors of extracellular signal-regulated kinase and NF-,B. Our study results suggest that CCL28 produced by keratinocytes is mediated by different signal pathways from CCL27 and that both CCL27 and CCL28 are involved in the pathogenesis of inflammatory skin diseases. [source] A clinical pharmacological study of the potential beneficial effects of a propolis food product as an adjuvant in asthmatic patientsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2003M. T. Khayyal Abstract The aqueous extract of propolis has been formulated as a nutritional food product and administered, as an adjuvant to therapy, to patients with mild to moderate asthma daily for 2 months in the framework of a comparative clinical study in parallel with a placebo preparation. The diagnosis of asthma was made according to the criteria of patient classification of the National Institutes of Health and Global Initiative for Asthma Management. At inclusion, the pulmonary forced expiratory volume in the first second (FEV1) as a percentage of the forced vital capacity (FVC) was more than 80% in mild persistent cases, and between 60 and 80% in moderate persistent cases, showing an increase in the degree of reversibility of >,15% in FEV1. All patients were on oral theophylline as controller therapy, none was receiving oral or inhaled corticosteroids, none had other comorbidities necessitating medical treatment, and all were from a middle-class community and had suffered from asthma for the last 2,5 years. Twenty-four patients received the placebo, with one drop-out during the study, while 22 received the propolis extract, with no drop-outs. The age range of the patients was 19,52 years; 36 were male and 10 female. The number of nocturnal attacks was recorded on a weekly basis, while pulmonary function tests were performed on all patients at the beginning of the trial, 1 month later and at the termination of the trial. Immunological parameters, including various cytokines and eicosanoids known to play a role in asthma, were measured in all patients at the beginning of the trial and 2 months later. Analysis of the results at the end of the clinical study revealed that patients receiving propolis showed a marked reduction in the incidence and severity of nocturnal attacks and improvement of ventilatory functions. The number of nocturnal attacks dropped from an average of 2.5 attacks per week to only 1. The improvement in pulmonary functions was manifested as a nearly 19% increase in FVC, a 29.5% increase in FEV1, a 30% increase in peak expiratory flow rate (PEFR), and a 41% increase in the forced expiratory flow rate between 25 and 75% of the vital capacity (FEF25-75). The clinical improvement was associated with decreases by 52, 65, 44 and 30%, respectively, of initial values for the pro-inflammatory cytokines tumor necrosis factor (TNF)-,, ICAM-1, interleukin (IL)-6 and IL-8, and a 3-fold increase in the ,protective' cytokine IL-10. The levels of prostaglandins E2 and F2, and leukotriene D4 were decreased significantly to 36, 39, and 28%, respectively, of initial values. Patients on the placebo preparation showed no significant improvement in ventilatory functions or in the levels of mediators. The findings suggest that the aqueous propolis extract tested is potentially effective as an adjuvant to therapy in asthmatic patients. The benefits may be related to the presence in the extract of caffeic acid derivatives and other active constituents. [source] Cellular iron status influences the functional relationship between microglia and oligodendrocytesGLIA, Issue 8 2006X. Zhang Abstract Previously, we have reported that there is a spatiotemporal relationship between iron accumulation in microglia and oligodendrocytes during normal development and in remyelination following injury. This in vivo observation has prompted us to develop a cell culture model to test the relationship between iron status of microglia and survival of oligodendrocytes. We found that conditioned media from iron-loaded microglia increases the survival of oligodendrocytes; but conditioned media from iron loaded activated microglia is toxic to oligodendrocytes. In the trophic condition, one of the proteins released by iron-loaded microglia is H-ferritin, and transfecting the microglia with siRNA for H-ferritin blocks the trophic response on oligodendrocytes. Lipopolysaccharide (LPS) activation decreases the amount of H-ferritin that is released from microglia and increases the release of the proinflammatory cytokines tumor necrosis factor-, and interleukin-1. LPS activation of iron-enriched microglia results in the activation of NF-kB and greater release of cytokines when compared with that of control microglia; whereas treating microglia with an iron chelator is associated with less NF-kB activation and less release of cytokines. These results indicate that microglia play an important role in iron homoeostasis and that their iron status can influence how microglia influence growth and survival of oligodendrocytes. The results further indicate that ferritin, released by microglia, is a significant source of iron for oligodendrocytes. © 2006 Wiley-Liss, Inc. [source] Endotoxin-stimulated macrophages decrease bile acid uptake in WIF-B cells, a rat hepatoma hybrid cell lineHEPATOLOGY, Issue 1 2000Ekkehard Sturm Endotoxemia leads to cytokine-mediated alterations of the hepatocellular sodium-taurocholate-cotransporting polypeptide (ntcp). We hypothesized that stimulated macrophages are essential transducers for down-regulating hepatocellular bile salt uptake in response to endotoxin (lipopolysaccharide [LPS]) exposure. Using an in vitro model, we exposed mouse macrophages (IC-21 cell line) to LPS for 24 hours. Concentrations of cytokines tumor necrosis factor-, (TNF-,), interleukin (IL)-1,, and IL-6 increased 10.6-fold, 12.5-fold, and 444-fold, respectively, in LPS-conditioned IC-21 medium (CM) versus unconditioned IC-21 medium (UM). WIF-B rat hepatoma hybrid cells were incubated with either CM or UM or treated directly with medium containing recombinant TNF-,, IL-1,, and IL-6. [3H]Taurocholate ([3H]TC) uptake decreased in WIF-B cells exposed to either TNF-, (54% of control), IL-1, (78%), IL-6 (55%) as single additives, or in triple combination (TCC) (43%). A virtually identical decrease was observed after exposing WIF-B cells to CM (52%, P < .001). LPS had no direct effect on [3H]TC uptake. CM treatment did not decrease L-alanine transport in WIF-B cells. Blocking antibodies against TNF-,, IL-1,, and IL-6 restored the diminished [3H]TC uptake in cells exposed to TCC and CM to 87% and 107% of controls, respectively. Northern blotting revealed that ntcp messenger RNA (mRNA) expression was significantly reduced in WIF-B cells after exposure to CM, and in primary rat hepatocytes exposed to CM or TNF-, (68%, 14%, and 29% of control, respectively). We conclude that macrophages and their ability to secrete the cytokines TNF-,, IL-1,, and IL-6 may be essential in mediating the endotoxin-induced cholestatic effect of decreased hepatocellular bile salt uptake. [source] Reciprocal activating interaction between 6-sulfo LacNAc+ dendritic cells and NK cellsINTERNATIONAL JOURNAL OF CANCER, Issue 2 2009Rebekka Wehner Abstract Dendritic cells (DCs) display an extraordinary capacity to induce T-cell responses providing the opportunity of DC-based cancer vaccination strategies. Additional findings indicate that DCs may also play a crucial role for the activation of natural killer (NK) cells, which are important effectors in innate antitumor immunity. However, studies investigating the interaction between native human DCs and NK cells are limited. Recently, we defined 6-sulfo LacNAc (slan) DCs as a major subpopulation of myeloid human blood DCs, which represent principal producers of the proinflammatory cytokines tumor necrosis factor-, and interleukin (IL)-12. Functional data revealed that slanDCs efficiently induce neoantigen-specific CD4+ T cells and activate tumor-reactive cytotoxic T cells. When evaluating the crosstalk between slanDCs and NK cells in this study, we found that lipopolysaccharide (LPS)-activated slanDCs efficiently enhance NK cell CD69 expression and interferon (IFN)-, secretion. NK cell-mediated tumor-directed cytotoxicity was significantly improved by slanDCs. NK cell activation induced by slanDCs was critically dependent on IL-12. When investigating the impact of NK cells on the immunostimulatory capacity of slanDCs, we observed that they promote DC maturation. In addition, NK cells strongly enhanced the secretion of immunomodulatory IL-12 and reduced the release of immunosuppressive IL-10 by slanDCs. IFN-, and cell-to-cell contact contributed to these effects. Furthermore, data revealed that DC-NK cell crosstalk improves slanDC-mediated differentiation of naïve CD4+ T lymphocytes into IFN-,-producing Th1 cells. In conclusion, we demonstrate a reciprocal activating interaction between slanDCs and NK cells, which may play a pivotal role in the regulation of antitumor immunity. © 2008 Wiley-Liss, Inc. [source] Morphine and HIV-Tat increase microglial-free radical production and oxidative stress: possible role in cytokine regulationJOURNAL OF NEUROCHEMISTRY, Issue 1 2009Jadwiga Turchan-Cholewo Abstract Opiate abuse alters the progression of human immunodeficiency virus and may increase the risk of neuroAIDS. As neuroAIDS is associated with altered microglial reactivity, the combined effects of human immunodeficiency virus-Tat and morphine were determined in cultured microglia. Specifically, experiments determined the effects of Tat and morphine on microglial-free radical production and oxidative stress, and on cytokine release. Data show that combined Tat and morphine cause early and synergistic increases in reactive oxygen species, with concomitant increases in protein oxidation. Furthermore, combined Tat and morphine, but not Tat or morphine alone, cause reversible decreases in proteasome activity. The effects of morphine on free radical production and oxidative stress are prevented by pre-treatment with naloxone, illustrating the important role of opioid receptor activation in these phenomena. While Tat is well known to induce cytokine release from cultured microglia, morphine decreases Tat-induced release of the cytokines tumor necrosis factor-, and interleukin-6, as well as the chemokine monocyte chemoattractant protein-1 (MCP-1). Finally, experiments using the reversible proteasome inhibitor MG115 show that temporary, non-cytotoxic decreases in proteasome activity increase protein oxidation and decrease tumor necrosis factor-,, interleukin-6, and MCP-1 release from microglia. Taken together, these data suggest that oxidative stress and proteasome inhibition may be involved in the immunomodulatory properties of opioid receptor activation in microglia. [source] Attenuation of proliferation in oligodendrocyte precursor cells by activated microgliaJOURNAL OF NEUROSCIENCE RESEARCH, Issue 8 2010Deanna L. Taylor Abstract Activated microglia can influence the survival of neural cells through the release of cytotoxic factors. Here, we investigated the interaction between Toll-like receptor 4 (TLR4)-activated microglia and oligodendrocytes or their precursor cells (OPC). Primary rat or N9 microglial cells were activated by exposure to TLR4-specifc lipopolysaccharide (LPS), resulting in mitogen-activated protein kinase activation, increased CD68 and inducible nitric oxide synthase expression, and release of the proinflammatory cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6). Microglial conditioned medium (MGCM) from LPS-activated microglia attenuated primary OPC proliferation without inducing cell death. The microglial-induced inhibition of OPC proliferation was reversed by stimulating group III metabotropic glutamate receptors in microglia with the agonist L-AP4. In contrast to OPC, LPS-activated MGCM enhanced the survival of mature oligodendrocytes. Further investigation suggested that TNF and IL-6 released from TLR4-activated microglia might contribute to the effect of MGCM on OPC proliferation, insofar as TNF depletion of LPS-activated MGCM reduced the inhibition of OPC proliferation, and direct addition of TNF or IL-6 attenuated or increased proliferation, respectively. OPC themselves were also found to express proteins involved in TLR4 signalling, including TLR4, MyD88, and MAL. Although LPS stimulation of OPC did not induce proinflammatory cytokine release or affect their survival, it did trigger JNK phosphorylation, suggesting that TLR4 signalling in these cells is active. These findings suggest that OPC survival may be influenced not only by factors released from endotoxin-activated microglia but also through a direct response to endotoxins. This may have consequences for myelination under conditions in which microglial activation and cerebral infection are both implicated. © 2010 Wiley-Liss, Inc. [source] Mechanical Ventilation Exacerbates Alveolar Macrophage Dysfunction in the Lungs of Ethanol-Fed RatsALCOHOLISM, Issue 8 2005Pradip P. Kamat Background: Patients with alcohol abuse have a two- to three-fold increased risk of acute lung injury and respiratory failure after sepsis or trauma but are also at increased risk of nosocomial pneumonia. Mechanical ventilation exacerbates lung injury during critical illnesses. In this study we tested whether mechanical ventilation of the alcoholic lung promotes on balance a proinflammatory phenotype favoring ventilator-induced lung injury or an immunosuppressive phenotype favoring ventilator-associated pneumonia. Methods: Lungs from rats fed an isocaloric diet with or without ethanol (six weeks) were isolated and ventilated ex vivo with a low-volume (protective) or high-volume (injurious) strategy for two hours with or without prior endotoxemia (two hours). In other experiments, rats were subjected to high-volume ventilation in vivo. Airway levels of the proinflammatory cytokines tumor necrosis factor-,, macrophage inflammatory protein-2, and interleukin-1, were determined after mechanical ventilation ex vivo and compared with edematous lung injury after high-volume ventilation in vivo. In parallel, alveolar macrophage phagocytosis of bacteria and secretion of interleukin-12 during ventilation ex vivo and endotoxin-stimulated alveolar macrophage phagocytosis and tumor necrosis factor-, secretion in vitro were determined. Results: Ethanol ingestion suppressed the proinflammatory response to injurious mechanical ventilation and did not increase experimental ventilator-induced lung injury. In parallel, ethanol ingestion blunted the innate immune response of alveolar macrophages during injurious ventilation ex vivo and after endotoxin stimulation in vitro. Conclusions: Ethanol ingestion dampens ventilator-induced inflammation but exacerbates macrophage immune dysfunction. These findings could explain at least in part why alcoholic patients are at increased risk of ventilator-associated pneumonia. [source] Tumor necrosis factor , and interleukin-1, modulate calcium and nitric oxide signaling in mechanically stimulated osteocytesARTHRITIS & RHEUMATISM, Issue 11 2009A. D. Bakker Objective Inflammatory diseases often coincide with reduced bone mass. Mechanoresponsive osteocytes regulate bone mass by maintaining the balance between bone formation and resorption. Despite its biologic significance, the effect of inflammation on osteocyte mechanoresponsiveness is not understood. To fill this gap, we investigated whether the inflammatory cytokines tumor necrosis factor , (TNF,) and interleukin-1, (IL-1,) modulate the osteocyte response to mechanical loading. Methods MLO-Y4 osteocytes were incubated with TNF, (0.5,30 ng/ml) or IL-1, (0.1,10 ng/ml) for 30 minutes or 24 hours, or with calcium inhibitors for 30 minutes. Cells were subjected to mechanical loading by pulsatile fluid flow (mean ± amplitude 0.7 ± 0.3 Pa, 5 Hz), and the response was quantified by measuring nitric oxide (NO) production using Griess reagent and by measuring intracellular calcium concentration ([Ca2+]i) using Fluo-4/AM. Focal adhesions and filamentous actin (F-actin) were visualized by immunostaining, and apoptosis was quantified by measuring caspase 3/7 activity. Cell-generated tractions were quantified using traction force microscopy, and cytoskeletal stiffness was quantified using optical magnetic twisting cytometry. Results Pulsatile fluid flow increased [Ca2+]i within seconds (in 13% of cells) and NO production within 5 minutes (4.7-fold). TNF, and IL-1, inhibited these responses. Calcium inhibitors decreased pulsatile fluid flow,induced NO production. TNF, and IL-1, affected cytoskeletal stiffness, likely because 24 hours of incubation with TNF, and IL-1, decreased the amount of F-actin. Incubation with IL-1, for 24 hours stimulated osteocyte apoptosis. Conclusion Our results suggest that TNF, and IL-1, inhibit mechanical loading,induced NO production by osteocytes via abrogation of pulsatile fluid flow,stimulated [Ca2+]i, and that IL-1, stimulates osteocyte apoptosis. Since both NO and osteocyte apoptosis affect osteoclasts, these findings provide a mechanism by which inflammatory cytokines might contribute to bone loss and consequently affect bone mass in rheumatoid arthritis. [source] A novel tumor necrosis factor ,,responsive CCAAT/enhancer binding protein site regulates expression of the cartilage-derived retinoic acid,sensitive protein gene in cartilageARTHRITIS & RHEUMATISM, Issue 5 2008Toshihiro Imamura Objective Inflammatory processes in rheumatoid arthritis are primarily regulated by the cytokines tumor necrosis factor , (TNF,) and interleukin-1, (IL-1,). Previous studies in our laboratory have shown that IL-1, represses expression of the cartilage characteristic genes, cartilage-derived retinoic acid,sensitive protein (cd - rap) and type II collagen (COL2A1); this mechanism of repression involves activation of a CCAAT/enhancer binding protein (c/EBP) site within promoter regions. The aim of this study was to investigate novel TNF,-mediated mechanisms that regulate the expression of cd - rap. Methods Rat chondrosarcoma cells were transiently transfected with complementary DNA constructs encoding cd - rap, in the presence of TNF,. The expression of c/EBP,, SOX9, and p300 in rat chondrosarcoma cells and primary human articular chondrocytes after treatment with TNF, was examined by reverse transcription,polymerase chain reaction and Western blotting. The effect of TNF, on endogenous binding of c/EBP, or SOX9 to the cd - rap promoter was examined by chromatin immunoprecipitation assays. Results We identified a new c/EBP binding site in the cd - rap promoter (from position ,1059 bp to position ,1046 bp). Binding of c/EBP to this site was regulated by TNF, but not IL-1,, resulting in down-regulation of cd - rap expression. This effect was reversed by mutational inactivation of the c/EBP motif. In addition, the activation potential of SOX9 and CREB binding protein/p300 on the cd - rap promoter was enhanced after mutation of the new c/EBP binding site, indicating that blockage of this site would increase transcription. Conclusion TNF, regulates the expression and/or DNA-binding potential of key positive-acting and negative-acting transcription factors that control the expression of the cartilage matrix gene, cd - rap. [source] A sodium dodecyl sulfate,polyacrylamide gel electrophoresis,liquid chromatography tandem mass spectrometry analysis of bovine cartilage tissue response to mechanical compression injury and the inflammatory cytokines tumor necrosis factor , and interleukin-1,ARTHRITIS & RHEUMATISM, Issue 2 2008Anna L. Stevens Objective To compare the response of chondrocytes and cartilage matrix to injurious mechanical compression and treatment with interleukin-1, (IL-1,) and tumor necrosis factor , (TNF,), by characterizing proteins lost to the medium from cartilage explant culture. Methods Cartilage explants from young bovine stifle joints were treated with 10 ng/ml of IL-1, or 100 ng/ml of TNF, or were subjected to uniaxial, radially-unconfined injurious compression (50% strain; 100%/second strain rate) and were then cultured for 5 days. Pooled media were subjected to gel-based separation (sodium dodecyl sulfate,polyacrylamide gel electrophoresis) and analysis by liquid chromatography tandem mass spectrometry, and the data were analyzed by Spectrum Mill proteomics software, focusing on protein identification, expression levels, and matrix protein proteolysis. Results More than 250 proteins were detected, including extracellular matrix (ECM) structural proteins, pericellular matrix proteins important in cell,cell interactions, and novel cartilage proteins CD109, platelet-derived growth factor receptor,like, angiopoietin-like 7, and adipocyte enhancer binding protein 1. IL-1, and TNF, caused increased release of chitinase 3,like protein 1 (CHI3L1), CHI3L2, complement factor B, matrix metalloproteinase 3, ECM-1, haptoglobin, serum amyloid A3, and clusterin. Injurious compression caused the release of intracellular proteins, including Grp58, Grp78, ,4-actinin, pyruvate kinase, and vimentin. Injurious compression also caused increased release and evidence of proteolysis of type VI collagen subunits, cartilage oligomeric matrix protein, and fibronectin. Conclusion Overload compression injury caused a loss of cartilage integrity, including matrix damage and cell membrane disruption, which likely occurred through strain-induced mechanical disruption of cells and matrix. IL-1, and TNF, caused the release of proteins associated with an innate immune and stress response by the chondrocytes, which may play a role in host defense against pathogens or may protect cells against stress-induced damage. [source] Increased expression of Fc, receptors II and III on macrophages of rheumatoid arthritis patients results in higher production of tumor necrosis factor , and matrix metalloproteinaseARTHRITIS & RHEUMATISM, Issue 4 2003Arjen B. Blom Objective To evaluate Fc, receptor (Fc,R) expression on synovial macrophages from rheumatoid arthritis (RA) patients and to determine whether this expression correlates with the production of the proinflammatory cytokines tumor necrosis factor , (TNF,), interleukin-1, (IL-1,), IL-12, and matrix metalloproteinase 1 (MMP-1). We also sought to determine whether mature macrophages from RA patients express aberrant levels of Fc,RI, Fc,RII, and Fc,RIII, and to determine the production of inflammatory mediators after immune complex (IC) stimulation. Methods Immunohistochemistry was performed on cryostat sections of synovial biopsy specimens obtained from 27 RA patients and 5 controls. Fc,R I, II, and III were detected, as well as the proinflammatory mediators IL-1, TNF,, IL-12, and MMP-1. Monocytes were isolated from the blood of 10 RA patients and 10 healthy controls and cultured for 7 days with macrophage colony-stimulating factor to obtain macrophages. Using fluorescence-activated cell sorting, the expression of Fc,RI, Fc,RII, and Fc,RIII was determined. On day 7, macrophages were stimulated with heat-aggregated gamma globulins (HAGGs) for 24 hours. Production of cytokines was measured using enzyme-linked immunosorbent assay, and production of gelatinases/collagenases was measured by degradation of fluorescent gelatin. Results Immunohistochemistry showed higher Fc,RII and Fc,RIII expression in RA synovium than in controls. Fc,RII and Fc,RIII, but not Fc,RI, were highly correlated with the number of synovial macrophages. Consistent with this, TNF, expression correlated positively with Fc,RIII expression. Moreover, MMP-1 expression strongly correlated with Fc,R I, II, and III expression. Mature macrophages from RA patients showed significantly enhanced expression of Fc,RII and Fc,RIII compared with controls. Twenty-four hours after stimulation of RA macrophages with HAGGs, significantly higher production of TNF, and gelatinase/collagenase was measured. Conclusion RA synovium and mature RA macrophages express significantly elevated levels of Fc,RII and Fc,RIII, resulting in much higher production of TNF, and gelatinase/collagenase after IC stimulation. These data suggest that disturbed expression of Fc,R on mature synovial macrophages is involved in the pathology of RA. [source] | |||||||||||||