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Proinflammatory Cytokine Expression (proinflammatory + cytokine_expression)
Selected AbstractsInhibition of Proinflammatory Cytokine Expression by NF-,B (p65) Antisense Oligonucleotide in Helicobacter pylori -Infected MiceHELICOBACTER, Issue 6 2005Sang Gyun Kim ABSTRACT Background.,Helicobacter pylori induces the expression of proinflammatory cytokines in vitro by activating nuclear factor-,B, a transcriptional regulator. However, it has not been clarified whether H. pylori -induced proinflammatory cytokines are also mediated through nuclear factor-,B in vivo. The aim of this study was to evaluate the role of nuclear factor-,B on the expressions of proinflammatory cytokines in H. pylori -infected mice. Materials and Methods., We evaluated nuclear factor-,B (p65) activation in the H. pylori -infected gastric mucosa of mice by immunofluorescent staining using antip65 polyclonal antibody, and the expressions of proinflammatory cytokines with inhibition of nuclear factor-,B pathway by using phosphorothioate antisense and sense oligonucleotide against the nuclear factor-,B (p65). Results., In the H. pylori -infected gastric mucosa of mice, immunofluorescent staining using antip65 polyclonal antibody showed nuclear factor-,B (p65) activation, which was particularly localized to epithelial cells. Tumor necrosis factor-, and interleukin-1, concentrations in gastric mucosa by enzyme-linked immunosorbent assay (ELISA) were elevated in the infected group versus the uninfected group. Pretreatment with nuclear factor-,B (p65) antisense oligonucleotide inhibited the activation of nuclear factor-,B and the expressions of tumor necrosis factor-, and interleukin-1, in H. pylori -infected gastric mucosa. Sense oligonucleotide did not influence on the expression of proinflammatory cytokines. Conclusions.,H. pylori infection was found to activate the expressions of proinflammatory cytokines via nuclear factor-,B in vivo, and this may play an important role in the initiation of H. pylori- induced gastric inflammation. [source] Induction of Innate Immune Gene Expression Cascades in Brain Slice Cultures by Ethanol: Key Role of NF-,B and Proinflammatory CytokinesALCOHOLISM, Issue 5 2010Jian Zou Background:, Postmortem human alcoholic brain has increased expression of proinflammatory cytokines (He and Crews, 2007). Nuclear factor ,B (NF-,B) is a transcription factor known to induce proinflammatory cytokine expression. Ethanol exposure increases NF-,B,DNA binding in rat brain (Crews et al., 2006) and in brain slice cultures in vitro (Zou and Crews, 2006). Using hippocampal-entorhinal cortex (HEC) brain slice cultures, we explored the effect of ethanol on NF-,B,DNA binding, proinflammatory gene expression, and sensitivity to glutamate neurotoxicity. Methods:, The HEC brain slice cultures are prepared from rats on P7 and used after 2 weeks in culture. NF-,B,DNA binding is determined by EMSA, NF-,B subunit,DNA binding by ELISA and mRNA by RT-PCR. Multiple antibody immunohistochemistry and confocal microscopy are used to characterize cell types expressing ethanol-induced genes. Results:, Ethanol treatment results in a progressive increase in NF-,B,DNA binding that includes large increases in NF-,B subunit p50 protein,DNA binding. The expression of NF-,B proinflammatory target genes progressively increased with time of ethanol treatment. Ethanol induces proinflammatory cytokines TNF,, MCP-1, and IL-1,, proinflammatory proteases TACE, and tissue plasminogen activator (tPA) as well as inducible nitric oxide synthase. Blockade of NF-,B by using NF-,B p65 siRNA and BHT reduces ethanol induction of proinflammatory genes. Neutralizing antibody to proinflammatory cytokine TNF, reduces ethanol induction of proinflammatory genes, suggesting cytokine propagation of proinflammatory gene induction. Furthermore, neutralizing antibodies to proinflammatory cytokines and protease tPA inhibitors blunt ethanol sensitization to glutamate neurotoxicity. Conclusions:, These findings indicate that ethanol treatment increases NF-,B,DNA binding and proinflammatory gene expression in brain slices. Ethanol-induced innate immune proinflammatory gene induction alters neurotransmission and likely contributes to alcoholic neurodegeneration. [source] Acute Alcohol Intoxication During Hemorrhagic Shock: Impact on Host Defense From InfectionALCOHOLISM, Issue 4 2004K. L. Zambell Abstract: Background: Acute alcohol intoxication is a frequent underlying condition associated with traumatic injury. Our studies have demonstrated that acute alcohol intoxication significantly impairs the immediate hemodynamic, metabolic, and inflammatory responses to hemorrhagic shock. This study investigated whether acute alcohol intoxication during hemorrhagic shock would alter the outcome from an infectious challenge during the initial 24 hr recovery period. Methods: Chronically catheterized male Sprague Dawley® rats were randomized to acute alcohol intoxication (EtOH; 1.75 g/kg bolus followed by a constant 15 hr infusion at 250,300 mg/kg/hr) or isocaloric isovolemic dextrose infusion (dex; 3 ml + 0.375 ml/hr). EtOH and dex were assigned to either fixed-volume (50%) hemorrhagic shock followed by fluid resuscitation with Ringer's lactate (EtOH/hem, dex/hem) or sham hemorrhagic shock (EtOH/sham, dex/sham). Indexes of circulating neutrophil function (apoptosis, phagocytosis, oxidative burst) were obtained at baseline, at completion of hemorrhagic shock, and at the end of fluid resuscitation. Bacterial clearance, lung cytokine expression, and myeloperoxidase activity were determined at 6 and 18 hr after an intratracheal challenge with Klebsiella pneumoniae (107 colony-forming units). Results: Mean arterial blood pressure was significantly lower in acute alcohol intoxication-hemorrhagic shock animals throughout the hemorrhagic shock. In sham animals, acute alcohol intoxication alone did not produce significant changes in neutrophil apoptosis or phagocytic activity but significantly suppressed phorbol myristic acid (PMA)-stimulated oxidative burst. Hemorrhagic shock produced a modest increase in neutrophil apoptosis and suppression of neutrophil phagocytic capacity but significantly suppressed PMA-stimulated oxidative burst. Acute alcohol intoxication exacerbated the hemorrhagic shock-induced neutrophil apoptosis and the hemorrhagic shock-induced suppression of phagocytosis without further affecting PMA-stimulated oxidative burst. Fluid resuscitation did not restore neutrophil phagocytosis or oxidative burst. Acute alcohol intoxication decreased (,40%) 3-day survival from K. pneumoniae in hemorrhagic shock animals, impaired bacterial clearance during the first 18 hr postinfection, and prolonged lung proinflammatory cytokine expression. Conclusions: These results demonstrate that the early alterations in metabolic and inflammatory responses to hemorrhagic shock produced by acute alcohol intoxication are associated with neutrophil dysfunction and impaired host response to a secondary infectious challenge leading to increased morbidity and mortality. [source] Quantitative Analysis of Inflammatory and Immune Responses in Dogs with Gastritis and Their Relationship to Helicobacter spp.JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2005Infection The present study sought to quantitatively examine mucosal inflammatory and immune responses in dogs with gastritis and the relationship of these responses to infection with Helicobacter. Gastric biopsies from 30 dogs were evaluated for B- and T-lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. Mucosal atrophy, fibrosis, cellularity, and severity of gastritis were graded qualitatively. Messenger-RNA (mRNA) for actin, interleukin-1, (IL-1,), IL-4, IL-8, and IL-10, transforming growth factor beta (TGF-,), and interferon gamma (IFN-,) was quantified by polymerase chain reaction (PCR). The presence of Helicobacter spp. was determined by urease activity, histology, PCR, and enzyme-linked immunosorbent assay. mRNA for IL-1,, IL-8, IL-10, TGF-,, and IFN-, was detected in most dogs. IL-4 mRNA was detected in only 1 dog. Correlations were observed for IL-1, versus IL-8 and IL-10; IL-8 versus IL-10, IFN-,, and TGF-,; and IL-10 versus IFN-,. Mucosal pathology was related to cytokine mRNA expression (neutrophils to IL-8 and IFN-,, macrophages and lymphocytes to IFN-,, and fibrosis to IL-1,). Gastritis was categorized as lymphoplasmacytic in all dogs, and its histologic severity correlated with atrophy, infiltration with lymphocytes and macrophages, and expression of IL-10 and IFN-,. Of the dogs examined, 76.7% were infected with Helicobacter spp. Infection was associated with increased expression of TGF-, and fibrosis. Circulating anti- Helicobacter immunoglobulin G titers were higher in uninfected than infected dogs. We conclude that lymphoplasmacytic gastritis in dogs is characterized by concurrent activation of proinflammatory and immunomodulatory cytokines, with increased mRNA expression related to mucosal pathology. No significant associations between Helicobacter infection and proinflammatory cytokine expression, severity of gastritis, or differences in the pathogenicity of different Helicobacter spp. were found. [source] Proinflammatory cytokine expression profile in degenerated and herniated human intervertebral disc tissuesARTHRITIS & RHEUMATISM, Issue 7 2010Mohammed F. Shamji Objective Prior reports document macrophage and lymphocyte infiltration with proinflammatory cytokine expression in pathologic intervertebral disc (IVD) tissues. Nevertheless, the role of the Th17 lymphocyte lineage in mediating disc disease remains uninvestigated. We undertook this study to evaluate the immunophenotype of pathologic IVD specimens, including interleukin-17 (IL-17) expression, from surgically obtained IVD tissue and from nondegenerated autopsy control tissue. Methods Surgical IVD tissues were procured from patients with degenerative disc disease (n = 25) or herniated IVDs (n = 12); nondegenerated autopsy control tissue was also obtained (n = 8) from the anulus fibrosus and nucleus pulposus regions. Immunohistochemistry was performed for cell surface antigens (CD68 for macrophages, CD4 for lymphocytes) and various cytokines, with differences in cellularity and target immunoreactivity scores analyzed between surgical tissue groups and between autopsy control tissue regions. Results Immunoreactivity for IL-4, IL-6, IL-12, and interferon-, (IFN,) was modest in surgical IVD tissue, although expression was higher in herniated IVD samples and virtually nonexistent in control samples. The Th17 lymphocyte product IL-17 was present in >70% of surgical tissue fields, and among control samples was detected rarely in anulus fibrosus regions and modestly in nucleus pulposus regions. Macrophages were prevalent in surgical tissues, particularly herniated IVD samples, and lymphocytes were expectedly scarce. Control tissue revealed lesser infiltration by macrophages and a near absence of lymphocytes. Conclusion Greater IFN, positivity, macrophage presence, and cellularity in herniated IVDs suggests a pattern of Th1 lymphocyte activation in this pathology. Remarkable pathologic IVD tissue expression of IL-17 is a novel finding that contrasts markedly with low levels of IL-17 in autopsy control tissue. These findings suggest involvement of Th17 lymphocytes in the pathomechanism of disc degeneration. [source] The ,7 nicotinic acetylcholine receptor on fibroblast-like synoviocytes and in synovial tissue from rheumatoid arthritis patients: A possible role for a key neurotransmitter in synovial inflammationARTHRITIS & RHEUMATISM, Issue 5 2009Marjolein A. Van Maanen Objective Recent studies have suggested an important role for neurotransmitters as modulators of inflammation. Therefore, we undertook this study to investigate the expression of the ,7 subunit of the nicotinic acetylcholine receptor (,7nAChR) and its function in rheumatoid arthritis (RA). Methods The potential role of the ,7nAChR in modulating proinflammatory cytokine expression in fibroblast-like synoviocytes (FLS) was identified by screening an adenoviral short hairpin RNA (Ad.shRNA) library. An ,7-specific antibody was used for immunohistochemistry, and fluorescein isothiocyanate,labeled ,-bungarotoxin, which binds specifically to the ,7nAChR, was used for immunofluorescence. Gene expression in FLS was determined by quantitative polymerase chain reaction with primers specific for the ,7nAChR. In addition, we analyzed messenger RNA (mRNA) expression of dup,7, a variant ,7 transcript. Next, we studied the functional role of the ,7nAChR in RA FLS by examining the effects of ,7-specific agonists on the production of interleukin-6 (IL-6) and IL-8 by activated FLS. Results A screen using an Ad.shRNA library against 807 transcripts revealed that a specific ,7nAChR shRNA potently modulated IL-8 and matrix metalloproteinase expression in FLS. The ,7nAChR was expressed in the inflamed synovium from RA patients, predominantly in the intimal lining layer. We found ,7nAChR expression at both the mRNA and protein level in cultured RA FLS. FLS also constitutively expressed dup,7 mRNA. Specific ,7nAChR agonists reduced tumor necrosis factor ,,induced IL-6 and IL-8 production by FLS. Conclusion The ,7nAChR and its dup,7 variant are expressed in RA synovium, where they may play a critical role in regulating inflammation. Targeting the ,7nAChR could provide a novel antiinflammatory approach to the treatment of RA. [source] ,-Tocopherol counteracts ritonavir-induced proinflammatory cytokines expression in differentiated THP-1 cellsBIOFACTORS, Issue 3-4 2007Weimin Guo Abstract Treatment of HIV-infected individuals with HIV protease inhibitor (HPI) drugs has significantly increased their life span. However, one of the side effects of HPI drugs is the development of premature atherosclerosis, whose molecular pathogenesis remains unclear. Previously we have reported that ,-tocopherol (,-T) normalizes CD36 overexpression induced by ritonavir treatment and reduces oxLDL uptake in THP-1 cells. Since inflammation is a major player in the pathogenesis of atherosclerosis, we hypothesized that HPI drugs, such as ritonavir, increase proinflammatory cytokines synthesis and that ,-T supplementation counteracts this effect by suppressing proinflammatory cytokines levels. Here, we report that after differentiating THP-1 cells to macrophages, ritonavir treatment (10 ,g/mL) significantly increases expression of proinflammatory cytokines, IL-6, MCP-1 and IL-8, at both mRNA and protein levels. This ritonavir-induced effect is significantly suppressed by treatment of THP-1/macrophages with 50 ,M ,-T. We conclude that ritonavir can induce proinflammatory cytokines synthesis in THP-1/macrophages, which might be associated with the development of premature atherosclerosis in ritonavir-treated patients and that this effect is prevented by ,-T. [source] | ||||||||||