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Sample records for tnf signaling contributes

  1. TNF-α- mediated-p38-dependent signaling pathway contributes to myocyte apoptosis in rats subjected to surgical trauma.

    Science.gov (United States)

    Wu, Huaxing; Wang, Guonian; Li, Shuai; Zhang, Mingyue; Li, Hulun; Wang, Kun

    2015-01-01

    The accumulation of cytokines in the plasma after trauma can induce myocyte apoptosis. We aimed to identify which cytokine(s) present in the plasma responsible for myocyte apoptosis, and delineated the signal transduction mechanism in rats subjected to surgical trauma. Rats were randomized into two groups: control and trauma groups, which was divided into five subgroups: posttraumatic 0, 3, 6, 12, and 24 h subgroups. Cardiomyocytes isolated from traumatized rats were incubated with one of the factors for 12 h (normal plasma; Cytomix; TNF-α; IL-1β; IFN-γ; trauma plasma; anti-TNF-α antibody; SB203580). Myocyte apoptosis, cytokine levels, and MAPKs activation, as the primary experimental outcomes, were measured by TUNEL, flow cytometry, ELISA and Western blot, respectively. Myocyte apoptosis was induced by surgical trauma during the early stage after trauma. Accompanying this change, plasma TNF-α, IL-1β, and IFN-γ levels were elevated in traumatized rats. Incubation of traumatized cardiomyocytes with cytomix or TNF-α alone induced myocyte apoptosis, and increased the activation of p38 and ERK1/2. Myocyte apoptosis and p38 activation were elevated in traumatized cardiomyocytes with trauma plasma, and these increases were partly abolished by anti-TNF-α antibody or SB203580. Our study demonstrated that there exists the TNF-α-mediated-p38-dependent signaling pathway that contributed to posttraumatic myocyte apoptosis of rats undergoing surgical trauma. © 2015 S. Karger AG, Basel.

  2. TNF-α- Mediated-p38-Dependent Signaling Pathway Contributes to Myocyte Apoptosis in Rats Subjected to Surgical Trauma

    Directory of Open Access Journals (Sweden)

    Huaxing Wu

    2015-03-01

    Full Text Available Background: The accumulation of cytokines in the plasma after trauma can induce myocyte apoptosis. We aimed to identify which cytokine(s present in the plasma responsible for myocyte apoptosis, and delineated the signal transduction mechanism in rats subjected to surgical trauma. Methods: Rats were randomized into two groups: control and trauma groups, which was divided into five subgroups: posttraumatic 0, 3, 6, 12, and 24 h subgroups. Cardiomyocytes isolated from traumatized rats were incubated with one of the factors for 12 h (normal plasma; Cytomix; TNF-α; IL-1β; IFN-γ; trauma plasma; anti-TNF-α antibody; SB203580. Myocyte apoptosis, cytokine levels, and MAPKs activation, as the primary experimental outcomes, were measured by TUNEL, flow cytometry, ELISA and Western blot, respectively. Results: Myocyte apoptosis was induced by surgical trauma during the early stage after trauma. Accompanying this change, plasma TNF-α, IL-1β, and IFN-γ levels were elevated in traumatized rats. Incubation of traumatized cardiomyocytes with cytomix or TNF-α alone induced myocyte apoptosis, and increased the activation of p38 and ERK1/2. Myocyte apoptosis and p38 activation were elevated in traumatized cardiomyocytes with trauma plasma, and these increases were partly abolished by anti-TNF-α antibody or SB203580. Conclusion: Our study demonstrated that there exists the TNF-α-mediated-p38-dependent signaling pathway that contributed to posttraumatic myocyte apoptosis of rats undergoing surgical trauma.

  3. Palmitoylation of TNF alpha is involved in the regulation of TNF receptor 1 signalling.

    Science.gov (United States)

    Poggi, Marjorie; Kara, Imène; Brunel, Jean-Michel; Landrier, Jean-François; Govers, Roland; Bonardo, Bernadette; Fluhrer, Regina; Haass, Christian; Alessi, Marie-Christine; Peiretti, Franck

    2013-03-01

    The pleiotropic pro-inflammatory cytokine tumour necrosis factor alpha (TNF) is synthesised as a transmembrane protein that is subject to palmitoylation. In this study, the roles of this acylation on TNF-mediated biological effects were investigated. We found that the lipid raft partitioning of TNF is regulated by its palmitoylation. Furthermore, we demonstrated that this palmitoylation process interferes with the cleavage/degradation of TNF intracellular fragments but is not involved in the regulation of its ectodomain shedding. Moreover, we found that the palmitoylation of TNF hinders the binding of soluble TNF to TNFR1 and regulates the integration/retention of TNFR1 into lipid rafts. Finally, we demonstrate that the transmembrane forms of wild-type and palmitoylation-defective TNF interact differently with TNFR1 and regulate NFκB activity, Erk1/2 phosphorylation and interleukin-6 synthesis differently, strongly suggesting that palmitoylation of TNF is involved in the regulation of TNFR1 signalling. An evidence for the physiological intervention of this regulation is provided by the fact that, in macrophages, the binding of endogenous soluble TNF to TNFR1 is enhanced by inhibition of palmitoylation. Therefore, our data introduce the new concept that palmitoylation of TNF is one of the means by which TNF-producing cells regulate their sensitivity to soluble TNF. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. TNF

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    Jamil, Kaiser; Jayaraman, Archana; Ahmad, Javeed; Joshi, Sindhu; Yerra, Shiva Kumar

    2017-09-01

    Several reports document the role of tumor necrosis factor alpha ( TNF-α ) and lipid metabolism in the context of acute inflammation as a causative factor in obesity-associated insulin resistance and as one of the causative parameter of type 2 diabetes mellitus (T2DM). Our aim was to investigate the association between -308G/A and -238G/A polymorphisms located in the promoter region of the TNF-α gene in T2DM in the Indian population with bioinformatics analysis of TNF-α protein networking with an aim to find new target sites for the treatment of T2DM. Demographics of 100 diabetes patients and 100 healthy volunteers were collected in a structured proforma and 3 ml blood samples were obtained from the study group, after approval of Institutional Ethics Committee of the hospital (IEC). The information on clinical parameters was obtained from medical records. Genomic DNA was extracted; PCR-RFLP was performed using TNF-α primers specific to detect the presence of SNPs. Various bioinformatics tools such as STRING software were used to determine its network with other associated genes. The PCR-RFLP studies showed that among the -238G/A types the GG genotype was 87%, GA genotype was 12% and AA genotype was 1%. Almost a similar pattern of results was obtained with TNF-α -308G/A polymorphism. The results obtained were evaluated statistically to determine the significance. By constructing TNF-α protein interaction network we could analyze ontology and hubness of the network to identify the networking of this gene which may influence the functioning of other genes in promoting T2DM. We could identify new targets in T2DM which may function in association with TNF-α . Through hub analysis of TNF-α protein network we have identified three novel proteins RIPK1, BIRC2 and BIRC3 which may contribute to TNF- mediated T2DM pathogenesis. In conclusion, our study indicated that some of the genotypes of TNF-α -308G/A, -238G/A were not significantly associated to type 2 diabetes

  5. TNFcontributes to postmenopausal osteoporosis by synergistically promoting RANKL-induced osteoclast formation.

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    Zha, Li; He, Li; Liang, Yijian; Qin, Hui; Yu, Bin; Chang, Linli; Xue, Li

    2018-03-20

    Previous studies showed that inflammatory cytokines promote osteoclast formation, characterized by the function of bone resorption. However, it remains unclear whether inflammatory factors contribute to osteoporosis syndrome in postmenopausal women. Here, we found that postmenopausal women with osteoporosis (PO) had increased levels of TNF-α, compared with those without osteoporosis. TNF-α is highly correlated with the RANK and estrogen levels in PO patients. in vitro, TNF-α synergistically promotes RANKL-induced osteoclast formation by activation of NF-κB and PI3K/Akt signaling. Moreover, inhibition of PI3K/Akt totally blocked the synergistic effects of TNF-α on NF-κB activation as well as osteoclast formation. Together, these results demonstrate that TNF-α synergistically promotes RANKL-induced osteoclasts formation through activation of PI3K/Akt signaling, which ultimately contributes to osteoporosis syndrome in postmenopausal women. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  6. MK2-TNF-Signaling Comes Full Circle.

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    Menon, Manoj B; Gaestel, Matthias

    2017-12-21

    MK2 (p38 MAPK -activated protein kinase 2) is essential for tumor necrosis factor (TNF) biosynthesis, mainly operating by post-transcriptional regulation. Deletion of the gene encoding MK2 strongly reduced serum TNF and protected against endotoxic shock, demonstrating the positive role of p38 MAPK /MK2 in TNF signaling at the level of ligand expression. Recent evidence indicates that MK2 directly phosphorylates the TNF receptor interactor RIPK1 and suppresses its activity, thereby limiting TNF-mediated apoptosis and necroptosis - pointing to a more complex, double-edged role of MK2 in TNF signaling. In addition, novel MK2 substrates have emerged in the DNA damage response, autophagy, and obesity, making MK2 a multifunctional kinase at the crossroads of stress response and cell death. We therefore propose a more general role of p38 MAPK /MK2 signaling in the timely coordinated onset and resolution of inflammation and beyond. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. AIP1: a new player in TNF signaling

    OpenAIRE

    Guicciardi, M. Eugenia; Gores, Gregory J.

    2003-01-01

    Apoptosis signal–regulating kinase 1 (ASK1) is an upstream activator of JNK and p38 MAPK signaling cascades. Evidence now shows that the ASK1-interacting protein, AIP1, plays an important role in TNF-α–induced ASK1 activation by facilitating dissociation from its inhibitor.

  8. Network dynamics determine the autocrine and paracrine signaling functions of TNF

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    Caldwell, Andrew B.; Cheng, Zhang; Vargas, Jesse D.; Birnbaum, Harry A.

    2014-01-01

    A hallmark of the inflammatory response to pathogen exposure is the production of tumor necrosis factor (TNF) that coordinates innate and adaptive immune responses by functioning in an autocrine or paracrine manner. Numerous molecular mechanisms contributing to TNF production have been identified, but how they function together in macrophages remains unclear. Here, we pursued an iterative systems biology approach to develop a quantitative understanding of the regulatory modules that control TNF mRNA synthesis and processing, mRNA half-life and translation, and protein processing and secretion. By linking the resulting model of TNF production to models of the TLR-, the TNFR-, and the NFκB signaling modules, we were able to study TNF’s functions during the inflammatory response to diverse TLR agonists. Contrary to expectation, we predicted and then experimentally confirmed that in response to lipopolysaccaride, TNF does not have an autocrine function in amplifying the NFκB response, although it plays a potent paracrine role in neighboring cells. However, in response to CpG DNA, autocrine TNF extends the duration of NFκB activity and shapes CpG-induced gene expression programs. Our systems biology approach revealed that network dynamics of MyD88 and TRIF signaling and of cytokine production and response govern the stimulus-specific autocrine and paracrine functions of TNF. PMID:25274725

  9. DMPD: Is HIV infection a TNF receptor signalling-driven disease? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18178131 Is HIV infection a TNF receptor signalling-driven disease? Herbein G, Khan... KA. Trends Immunol. 2008 Feb;29(2):61-7. (.png) (.svg) (.html) (.csml) Show Is HIV infection a TNF receptor signalling-driven dise...ase? PubmedID 18178131 Title Is HIV infection a TNF receptor signalling-driven diseas

  10. SPATA2 links CYLD to the TNF-α receptor signaling complex and modulates the receptor signaling outcomes

    DEFF Research Database (Denmark)

    Wagner, Sebastian A; Satpathy, Shankha; Beli, Petra

    2016-01-01

    TNF-α is a key regulator of innate immune and proinflammatory responses. However, the composition of the TNF-α receptor-associated signaling complexes (TNF-RSC) and the architecture of the downstream signaling networks are incompletely understood. We employed quantitative mass spectrometry...... to demonstrate that TNF-α stimulation induces widespread protein phosphorylation and that the scope of phosphorylation expands in a temporal manner. TNF-α stimulation also induces rapid ubiquitylation of components of the TNF-RSC Temporal analysis of the TNF-RSC composition identified SPATA2 as a novel component...

  11. TNF signaling inhibition in the CNS: implications for normal brain function and neurodegenerative disease

    Directory of Open Access Journals (Sweden)

    Tansey Malú G

    2008-10-01

    Full Text Available Abstract The role of tumor necrosis factor (TNF as an immune mediator has long been appreciated but its function in the brain is still unclear. TNF receptor 1 (TNFR1 is expressed in most cell types, and can be activated by binding of either soluble TNF (solTNF or transmembrane TNF (tmTNF, with a preference for solTNF; whereas TNFR2 is expressed primarily by microglia and endothelial cells and is preferentially activated by tmTNF. Elevation of solTNF is a hallmark of acute and chronic neuroinflammation as well as a number of neurodegenerative conditions including ischemic stroke, Alzheimer's (AD, Parkinson's (PD, amyotrophic lateral sclerosis (ALS, and multiple sclerosis (MS. The presence of this potent inflammatory factor at sites of injury implicates it as a mediator of neuronal damage and disease pathogenesis, making TNF an attractive target for therapeutic development to treat acute and chronic neurodegenerative conditions. However, new and old observations from animal models and clinical trials reviewed here suggest solTNF and tmTNF exert different functions under normal and pathological conditions in the CNS. A potential role for TNF in synaptic scaling and hippocampal neurogenesis demonstrated by recent studies suggest additional in-depth mechanistic studies are warranted to delineate the distinct functions of the two TNF ligands in different parts of the brain prior to large-scale development of anti-TNF therapies in the CNS. If inactivation of TNF-dependent inflammation in the brain is warranted by additional pre-clinical studies, selective targeting of TNFR1-mediated signaling while sparing TNFR2 activation may lessen adverse effects of anti-TNF therapies in the CNS.

  12. Chronic ethanol exposure inhibits distraction osteogenesis in a mouse model: Role of the TNF signaling axis

    International Nuclear Information System (INIS)

    Wahl, Elizabeth C.; Aronson, James; Liu, Lichu; Liu, Zhendong; Perrien, Daniel S.; Skinner, Robert A.; Badger, Thomas M.; Ronis, Martin J.J.; Lumpkin, Charles K.

    2007-01-01

    Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine that modulates osteoblastogenesis. In addition, the demonstrated inhibitory effects of chronic ethanol exposure on direct bone formation in rats are hypothetically mediated by TNFsignaling. The effects in mice are unreported. Therefore, we hypothesized that in mice (1) administration of a soluble TNF receptor 1 derivative (sTNF-R1) would protect direct bone formation during chronic ethanol exposure, and (2) administration of recombinant mouse TNF-α (rmTNF-α) to ethanol naive mice would inhibit direct bone formation. We utilized a unique model of limb lengthening (distraction osteogenesis, DO) combined with liquid diets to measure chronic ethanol's effects on direct bone formation. Chronic ethanol exposure resulted in increased marrow TNF, IL-1, and CYP 2E1 RNA levels in ethanol-treated vs. control mice, while no significant weight differences were noted. Systemic administration of sTNF-R1 during DO (8.0 mg/kg/2 days) to chronic ethanol-exposed mice resulted in enhanced direct bone formation as measured radiologically and histologically. Systemic rmTNF-α (10 μg/kg/day) administration decreased direct bone formation measures, while no significant weight differences were noted. We conclude that chronic ethanol-associated inhibition of direct bone formation is mediated to a significant extent by the TNF signaling axis in a mouse model

  13. TNF signaling in non-alcoholic fatty liver disease

    NARCIS (Netherlands)

    Vergara, Marcela Aparicio

    2013-01-01

    Tumornecrosefactor-alpha (TNF-α, een eiwit dat verantwoordelijk is voor het proces van celdood en cel-ontsteking), speelt via receptor TNFR1 een centrale rol in het ontstaan van niet-alcoholische leververvetting (NAFLD). Maar anders dan tot nu toe gedacht, bestaat er geen verband tussen

  14. Inhibiting TNFsignaling does not attenuate induction of endotoxin tolerance

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    Loosbroock C

    2014-12-01

    Full Text Available Christopher Loosbroock, Kenneth W Hunter Department of Microbiology and Immunology, University of Nevada School of Medicine, Reno, NV, USA Abstract: Tumor necrosis factor-alpha (TNF-α is a central mediator of inflammatory responses elicited by Toll-like receptor agonists, such as the Gram-negative bacterial outer membrane antigen lipopolysaccharide (LPS. TNF-α is responsible for altering vascular permeability and activating infiltrating inflammatory cells, such as monocytes and neutrophils. Interestingly, TNF-α has also demonstrated the ability to induce tolerance to subsequent challenges with TNF-α or LPS in monocyte and macrophage cell populations. Tolerance is characterized by the inability to mount a typical inflammatory response during subsequent challenges following the initial exposure to an inflammatory mediator such as LPS. The ability of TNF-α to induce a tolerant-like state with regard to LPS is most likely a regulatory mechanism to prevent excessive inflammation. We hypothesized that the induction of tolerance or the degree of tolerance is dependent upon the production of TNF-α during the primary response to LPS. To investigate TNF-α-dependent tolerance, human monocytic THP-1 cells were treated with TNF-α-neutralizing antibodies or antagonistic TNF-α receptor antibodies before primary LPS stimulation and then monitored for the production of TNF-α during the primary and challenge stimulation. During the primary stimulation, anti-TNF-α treatment effectively attenuated the production of TNF-α and interleukin-1β; however, this reduced production did not impact the induction of endotoxin tolerance. These results demonstrate that interfering with TNFsignaling attenuates production of inflammatory cytokines without affecting the induction of tolerance. Keywords: endotoxin tolerance, lipopolysaccharide, tumor necrosis factor-alpha, anti-tumor necrosis factor-alpha, THP-1 cells

  15. Effect of TNF-Alpha on Caveolin-1 Expression and Insulin Signaling During Adipocyte Differentiation and in Mature Adipocytes

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    Sara Palacios-Ortega

    2015-07-01

    Full Text Available Background/Aims: Tumor necrosis factor-α (TNF-α-mediated chronic low-grade inflammation of adipose tissue is associated with obesity and insulin resistance. Caveolin-1 (Cav-1 is the central component of adipocyte caveolae and has an essential role in the regulation of insulin signaling. The effects of TNF-α on Cav-1 expression and insulin signaling during adipocyte differentiation and in mature adipocytes were studied. Methods: 3T3-L1 cells were differentiated (21 days in the presence TNF-α (10 ng/mL and mature adipocytes were also treated with TNF-α for 48 hours. Cav-1 and insulin receptor (IR gene methylation were determined as well as Cav-1, IR, PKB/AKT-2 and Glut-4 expression and activation by real time RT-PCR and western blot. Baseline and insulin-induced glucose uptake was measured by the 2-[C14]-deoxyglucose uptake assay. Results: TNF-α slowed down the differentiation program, hindering the expression of some insulin signaling intermediates without fully eliminating insulin-mediated glucose uptake. In mature adipocytes, TNF-α did not compromise lipid-storage capacity, but downregulated the expression of the insulin signaling intermediates, totally blocking insulin-mediated glucose uptake. Insulin sensitivity correlated with the level of activated phospho-Cav-1 in both situations, strongly suggesting the direct contribution of Cav-1 to the maintenance of this physiological response. Conclusion: Cav-1 activation by phosphorylation seems to be essential for the maintenance of an active and insulin-sensitive glucose uptake.

  16. Multiple signal transduction pathways regulate TNF-induced actin reorganization in macrophages: inhibition of Cdc42-mediated filopodium formation by TNF

    NARCIS (Netherlands)

    Peppelenbosch, M.; Boone, E.; Jones, G. E.; van Deventer, S. J.; Haegeman, G.; Fiers, W.; Grooten, J.; Ridley, A. J.

    1999-01-01

    TNF is known to regulate macrophage (Mphi) migration, but the signaling pathways mediating this response have not been established. Here we report that stimulation of the 55-kDa TNF receptor (TNFR-1) induced an overall decrease in filamentous actin (F-actin), inhibited CSF-1- and Cdc42-dependent

  17. TNF-α promotes osteoclastogenesis through JNK signaling-dependent induction of Semaphorin3D expression in estrogen-deficiency induced osteoporosis.

    Science.gov (United States)

    Sang, Chenglin; Zhang, Jiefeng; Zhang, Yongxian; Chen, Fangjing; Cao, Xuecheng; Guo, Lei

    2017-12-01

    Tumor necrosis factor α (TNF-α)-induced osteoclast formation have been demonstrated to play an important role in the pathogenesis of estrogen deficiency-mediated bone loss, but the exact mechanisms by which TNF-α enhanced osteoclast differentiation were not fully elucidated. The class III semaphorins members were critical to regulate bone homeostasis. Here, we identified a novel mechanism whereby TNF-α increasing Semaphorin3D expression contributes to estrogen deficiency-induced osteoporosis. In this study, we found that Semaphorin3D expression was upregulated by TNF-α during the process of RANKL-induced osteoclast differentiation. Inhibition of Semaphorin3D in pre-osteoclasts could attenuate the stimulatory effects of TNF-α on osteoclast proliferation and differentiation. Mechanistically, blocking of the Jun N-terminal kinase (JNK) signaling markedly rescued TNF-α-induced Semaphorin3D expression, suggesting that JNK signaling was involved in the regulation of Semaphorin3D expression by TNF-α. In addition, silencing of Semaphorin3D in vivo could alleviate estrogen deficiency-induced osteoporosis. Our results revealed a novel function for Semaphorin3D and suggested that increased Semaphorin3D may contribute to enhanced bone loss by increased TNF-α in estrogen deficiency-induced osteoporosis. Thus, Semaphorin3D may provide a potential therapeutic target for the treatment of estrogen-deficiency induced osteoporosis. © 2017 Wiley Periodicals, Inc.

  18. Histamine Derived from Probiotic Lactobacillus reuteri Suppresses TNF via Modulation of PKA and ERK Signaling

    Science.gov (United States)

    Thomas, Carissa M.; Hong, Teresa; van Pijkeren, Jan Peter; Hemarajata, Peera; Trinh, Dan V.; Hu, Weidong; Britton, Robert A.; Kalkum, Markus; Versalovic, James

    2012-01-01

    Beneficial microbes and probiotic species, such as Lactobacillus reuteri, produce biologically active compounds that can modulate host mucosal immunity. Previously, immunomodulatory factors secreted by L. reuteri ATCC PTA 6475 were unknown. A combined metabolomics and bacterial genetics strategy was utilized to identify small compound(s) produced by L. reuteri that were TNF-inhibitory. Hydrophilic interaction liquid chromatography-high performance liquid chromatography (HILIC-HPLC) separation isolated TNF-inhibitory compounds, and HILIC-HPLC fraction composition was determined by NMR and mass spectrometry analyses. Histamine was identified and quantified in TNF-inhibitory HILIC-HPLC fractions. Histamine is produced from L-histidine via histidine decarboxylase by some fermentative bacteria including lactobacilli. Targeted mutagenesis of each gene present in the histidine decarboxylase gene cluster in L. reuteri 6475 demonstrated the involvement of histidine decarboxylase pyruvoyl type A (hdcA), histidine/histamine antiporter (hdcP), and hdcB in production of the TNF-inhibitory factor. The mechanism of TNF inhibition by L. reuteri-derived histamine was investigated using Toll-like receptor 2 (TLR2)-activated human monocytoid cells. Bacterial histamine suppressed TNF production via activation of the H2 receptor. Histamine from L. reuteri 6475 stimulated increased levels of cAMP, which inhibited downstream MEK/ERK MAPK signaling via protein kinase A (PKA) and resulted in suppression of TNF production by transcriptional regulation. In summary, a component of the gut microbiome, L. reuteri, is able to convert a dietary component, L-histidine, into an immunoregulatory signal, histamine, which suppresses pro-inflammatory TNF production. The identification of bacterial bioactive metabolites and their corresponding mechanisms of action with respect to immunomodulation may lead to improved anti-inflammatory strategies for chronic immune-mediated diseases. PMID:22384111

  19. Histamine derived from probiotic Lactobacillus reuteri suppresses TNF via modulation of PKA and ERK signaling.

    Directory of Open Access Journals (Sweden)

    Carissa M Thomas

    Full Text Available Beneficial microbes and probiotic species, such as Lactobacillus reuteri, produce biologically active compounds that can modulate host mucosal immunity. Previously, immunomodulatory factors secreted by L. reuteri ATCC PTA 6475 were unknown. A combined metabolomics and bacterial genetics strategy was utilized to identify small compound(s produced by L. reuteri that were TNF-inhibitory. Hydrophilic interaction liquid chromatography-high performance liquid chromatography (HILIC-HPLC separation isolated TNF-inhibitory compounds, and HILIC-HPLC fraction composition was determined by NMR and mass spectrometry analyses. Histamine was identified and quantified in TNF-inhibitory HILIC-HPLC fractions. Histamine is produced from L-histidine via histidine decarboxylase by some fermentative bacteria including lactobacilli. Targeted mutagenesis of each gene present in the histidine decarboxylase gene cluster in L. reuteri 6475 demonstrated the involvement of histidine decarboxylase pyruvoyl type A (hdcA, histidine/histamine antiporter (hdcP, and hdcB in production of the TNF-inhibitory factor. The mechanism of TNF inhibition by L. reuteri-derived histamine was investigated using Toll-like receptor 2 (TLR2-activated human monocytoid cells. Bacterial histamine suppressed TNF production via activation of the H(2 receptor. Histamine from L. reuteri 6475 stimulated increased levels of cAMP, which inhibited downstream MEK/ERK MAPK signaling via protein kinase A (PKA and resulted in suppression of TNF production by transcriptional regulation. In summary, a component of the gut microbiome, L. reuteri, is able to convert a dietary component, L-histidine, into an immunoregulatory signal, histamine, which suppresses pro-inflammatory TNF production. The identification of bacterial bioactive metabolites and their corresponding mechanisms of action with respect to immunomodulation may lead to improved anti-inflammatory strategies for chronic immune-mediated diseases.

  20. Impact of TNF-R1 and CD95 internalization on apoptotic and antiapoptotic signaling.

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    Schütze, Stefan; Schneider-Brachert, Wulf

    2009-01-01

    Internalization of cell surface receptors has long been regarded as a pure means to terminate signaling via receptor degradation. A growing body of information points to the fact that many internalized receptors are still in their active state and that signaling continues along the endocytic pathway. Thus endocytosis orchestrates cell signaling by coupling and integrating different cascades on the surface of endocytic vesicles to control the quality, duration, intensity, and distribution of signaling events. The death receptors tumor necrosis factor-receptor 1 (TNF-R1) and CD95 (Fas, APO-1) are known not only to signal for cell death via apoptosis but are also capable of inducing antiapoptotic signals via transcription factor NF-kappaB induction or activation of the proliferative mitogen-activated protein kinase (MAPK)/ERK (extracellular signal-regulated kinase) protein kinase cascades, resulting in cell protection and tissue regeneration. A clue to the understanding of these contradictory biological phenomena may arise from recent findings which reveal a regulatory role of receptor internalization and intracellular receptor trafficking in selectively transmitting signals, which lead either to apoptosis or to the survival of the cell. In this chapter, we discuss the dichotomy of pro- and antiapoptotic signaling of the death receptors TNF-R1 and CD95. First, we will address the role of lipid rafts and post-translational modifications of death receptors in regulating the formation of receptor complexes. Then, we will discuss the role of internalization in determining the fate of the receptors and subsequently the specificity of signaling events. We propose that fusion of internalized TNF-receptosomes with trans-Golgi vesicles should be recognized as a novel mechanism to transduce death signals along the endocytic route. Finally, the lessons learnt from the strategy of adenovirus to escape apoptosis by targeting death receptor internalization demonstrate the

  1. TNF-α Mediates the Intrinsic and Extrinsic Pathway in Propofol-Induced Neuronal Apoptosis Via PI3K/Akt Signaling Pathway in Rat Prefrontal Cortical Neurons.

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    Deng, Xiaoyuan; Chen, Bo; Wang, Bin; Zhang, Junfang; Liu, Hongliang

    2017-10-01

    Propofol can cause developing neuronal apoptosis in both in vivo and in vitro studies, and the mechanism is unclear till now. Our previous study has demonstrated that propofol can increase the TNF-α expression in the prefrontal cortex in rat developing brain, the TNF-α antagonist, etanercept, can inhibit propofol-induced neuronal apoptosis, but little is known about how TNF-α mediates that process. This study reveals that propofol at clinically relevant concentrations increases the TNF-α synthesis and release in neurons, and induces neuronal apoptosis; etanercept significantly reduces neuronal apoptosis, the elevation of cleaved caspase-8 and cleaved caspase-9, or the Akt phosphorylation induced by propofol, while the selective PI3K antagonist blocks the neuroprotection of etanercept. Propofol does not change the expression of P2X7 receptor in neurons, and the P2X7 receptor antagonist cannot affect the TNF-α synthesis or release after propofol treatment. These results suggest that propofol can increase the synthesis and release of TNF-α in the primary cultured prefrontal cortical neurons, TNFcontributes to the intrinsic and extrinsic pathway in propofol-induced neuronal apoptosis via PI3K/Akt signaling pathway, and P2X7R is not involved in the synthesis and release of TNF-α induced by propofol.

  2. Transmembrane TNF-dependent uptake of anti-TNF antibodies.

    Science.gov (United States)

    Deora, Arun; Hegde, Subramanya; Lee, Jacqueline; Choi, Chee-Ho; Chang, Qing; Lee, Cheryl; Eaton, Lucia; Tang, Hua; Wang, Dongdong; Lee, David; Michalak, Mark; Tomlinson, Medha; Tao, Qingfeng; Gaur, Nidhi; Harvey, Bohdan; McLoughlin, Shaun; Labkovsky, Boris; Ghayur, Tariq

    TNF-α (TNF), a pro-inflammatory cytokine is synthesized as a 26 kDa protein, anchors in the plasma membrane as transmembrane TNF (TmTNF), and is subjected to proteolysis by the TNF-α converting enzyme (TACE) to release the 15 kDa form of soluble TNF (sTNF). TmTNF and sTNF interact with 2 distinct receptors, TNF-R1 (p55) and TNF-R2 (p75), to mediate the multiple biologic effects of TNF described to date. Several anti-TNF biologics that bind to both forms of TNF and block their interactions with the TNF receptors are now approved for the treatment of a variety of immune-mediated diseases. Several reports suggest that binding of anti-TNFs to TmTNF delivers an outside-to-inside 'reverse' signal that may also contribute to the efficacy of anti-TNFs. Some patients, however, develop anti-TNF drug antibody responses (ADA or immunogenicity). Here, we demonstrate biochemically that TmTNF is transiently expressed on the surface of lipopolysaccharide-stimulated primary human monocytes, macrophages, and monocyte-derived dendritic cells (DCs) and expression of TmTNF on the cell surface is enhanced following treatment of cells with TAPI-2, a TACE inhibitor. Importantly, binding of anti-TNFs to TmTNF on DCs results in rapid internalization of the anti-TNF/TmTNF complex first into early endosomes and then lysosomes. The internalized anti-TNF is processed and anti-TNF peptides can be eluted from the surface of DCs. Finally, tetanus toxin peptides fused to anti-TNFs are presented by DCs to initiate T cell recall proliferation response. Collectively, these observations may provide new insights into understanding the biology of TmTNF, mode of action of anti-TNFs, biology of ADA response to anti-TNFs, and may help with the design of the next generation of anti-TNFs.

  3. TNFR1 mediates TNF-α-induced tumour lymphangiogenesis and metastasis by modulating VEGF-C-VEGFR3 signalling

    DEFF Research Database (Denmark)

    Ji, Hong; Cao, Renhai; Yang, Yunlong

    2014-01-01

    Inflammation and lymphangiogenesis are two cohesively coupled processes that promote tumour growth and invasion. Here we report that TNF-α markedly promotes tumour lymphangiogenesis and lymphatic metastasis. The TNF-α-TNFR1 signalling pathway directly stimulates lymphatic endothelial cell activit...

  4. Astrocyte reactivity to unconjugated bilirubin requires TNF-α and IL-1β receptor signaling pathways.

    Science.gov (United States)

    Fernandes, Adelaide; Barateiro, Andreia; Falcão, Ana Sofia; Silva, Sandra Leit-Ao; Vaz, Ana Rita; Brito, Maria Alexandra; Silva, Rui Fernando Marques; Brites, Dora

    2011-01-01

    Jaundice and sepsis are common neonatal conditions that can lead to neurodevelopment sequelae, namely if present at the same time. We have reported that tumor necrosis factor (TNF)-α and interleukin (IL)-1β are produced by cultured neurons and mainly by glial cells exposed to unconjugated bilirubin (UCB). The effects of these cytokines are mediated by cell surface receptors through a nuclear factor (NF)-κB-dependent pathway that we have showed to be activated by UCB. The present study was designed to evaluate the role of TNF-α and IL-1β signaling on astrocyte reactivity to UCB in rat cortical astrocytes. Exposure of astrocytes to UCB increased the expression of both TNF-α receptor (TNFR)1 and IL-1β receptor (IL-1R)1, but not TNFR2, as well as their activation, observed by augmented binding of receptors' molecular adaptors, TRAF2 and TRAF6, respectively. Silencing of TNFR1, using siRNA technology, or blockade of IL-1β cascade, using its endogenous antagonist, IL-1 receptor antagonist (IL-1ra), prevented UCB-induced cytokine release and NF-κB activation. Interestingly, lack of TNFsignal transduction reduced UCB-induced cell death for short periods of incubation, although an increase was observed after extended exposure; in contrast, inhibition of IL-1β cascade produced a sustained blockade of astrocyte injury by UCB. Together, our data show that inflammatory pathways are activated during in vitro exposure of rat cortical astrocytes to UCB and that this activation is prolonged in time. This supports the concept that inflammatory pathways play a role in brain damage by UCB, and that they may represent important pharmacological targets. Copyright © 2010 Wiley-Liss, Inc.

  5. Chronicles of a death foretold: dual sequential cell death checkpoints in TNF signaling.

    Science.gov (United States)

    O'Donnell, Marie Anne; Ting, Adrian T

    2010-03-15

    The kinase RIP1 wears a coat of many colors during TNF receptor signaling and can regulate both activation of pro-survival NFkB and programmed cell death pathways. In this review, we outline how coating RIP1 with K63-linked ubiquitin chains forms a protective layer that prevents RIP1 from binding apoptotic regulators and serves as an early guard against cell death. Further on, binding of NFkB signaling components to the ubiquitin coat of RIP1 activates long-term pro-survival signaling and forms a more impenetrable suit of armor against cell death. If RIP1 is not decorated with ubiquitin chains it becomes an unstoppable harbinger of bad news: programmed cell death.

  6. Gallic acid induces necroptosis via TNFsignaling pathway in activated hepatic stellate cells.

    Directory of Open Access Journals (Sweden)

    Ya Ju Chang

    Full Text Available Gallic acid (3, 4, 5-trihydroxybenzoic acid, GA, a natural phenolic acid widely found in gallnuts, tea leaves and various fruits, possesses several bioactivities against inflammation, oxidation, and carcinogenicity. The beneficial effect of GA on the reduction of animal hepatofibrosis has been indicated due to its antioxidative property. However, the cytotoxicity of GA autoxidation causing cell death has also been reported. Herein, we postulated that GA might target activated hepatic stellate cells (aHSCs, the cell type responsible for hepatofibrosis, to mitigate the process of fibrosis. The molecular cytotoxic mechanisms that GA exerted on aHSCs were then analyzed. The results indicated that GA elicited aHSC programmed cell death through TNF-α-mediated necroptosis. GA induced significant oxidative stress through the suppression of catalase activity and the depletion of glutathione (GSH. Elevated oxidative stress triggered the production of TNF-α facilitating the undergoing of necroptosis through the up-regulation of key necroptotic regulatory proteins TRADD and receptor-interacting protein 3 (RIP3, and the inactivation of caspase-8. Calmodulin and calpain-1 activation were engaged, which promoted subsequent lysosomal membrane permeabilization (LMP. The TNF-α antagonist (SPD-304 and the RIP1 inhibitor (necrostatin-1, Nec-1 confirmed GA-induced TNFR1-mediated necroptosis. The inhibition of RIP1 by Nec-1 diverted the cell death from necroptosis to apoptosis, as the activation of caspase 3 and the increase of cytochrome c. Collectively, this is the first report indicating that GA induces TNF signaling-triggered necroptosis in aHSCs, which may offer an alternative strategy for the amelioration of liver fibrosis.

  7. Resveratrol prevents TNF-α-induced muscle atrophy via regulation of Akt/mTOR/FoxO1 signaling in C2C12 myotubes.

    Science.gov (United States)

    Wang, Dong-Tao; Yin, Yi; Yang, Ya-Jun; Lv, Pei-Jia; Shi, Ying; Lu, Lu; Wei, Lian-Bo

    2014-04-01

    Muscle atrophy poses a serious concern to patients inflicted with inflammatory diseases. There is now increasing evidence which suggests a vital role for tumor necrosis factor alpha (TNF-α) in muscle pathology associated with impairment of differentiation and muscle wasting. Resveratrol has been an ascribed inhibitory effect on glucocorticoid-induced muscle atrophy in vitro, but the influence of resveratrol on the growth of C2C12 myotubes exposed to TNF-α remains unclear. The present study aimed to investigate the involvement of TNF-α in the regulation of skeletal muscle hypertrophy and atrophy, and the possibility to interfere with such modulations by means of resveratrol supplementation. For this purpose, C2C12 myotubes were treated with TNF-α in the presence or absence of resveratrol. Myotube treatment with TNFcontributes to both hyperexpression of the muscle-specific ubiquitin ligase MAFbx and MuRF1, and these alterations are linked to a decrease of anabolic targets (Akt, mTOR, p70S6k and 4E-BP1) and an increase of catabolic targets (FoxO1, FoxO3a, MAFbx and MuRF1). Resveratrol supplementation effectively counteracts TNF-α induced muscle protein loss and reverses declining expression of Akt, mTOR, p70S6K, 4E-BP1and FoxO1, but exerts no influence of FoxO3a expression. Our study demonstrates that resveratrol can reverse the muscle cell atrophy caused by TNF-α through regulation of the Akt/mTOR/FoxO1 signaling pathways, followed by inhibition of the atrophy-related ubiquitin ligase. Our findings suggested that resveratrol could represent a possible strategy to improve muscle mass. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Src Family Kinases Modulate the Loss of Endothelial Barrier Function in Response to TNF-α: Crosstalk with p38 Signaling.

    Directory of Open Access Journals (Sweden)

    Alejandro P Adam

    Full Text Available Activation of Src Family Kinase (SFK signaling is required for the increase in endothelial permeability induced by a variety of cytokines and growth factors. However, we previously demonstrated that activation of endogenous SFKs by expression of dominant negative C-terminal Src Kinase (DN-Csk is not sufficient to decrease endothelial adherens junction integrity. Basal SFK activity has been observed in normal venular endothelia and was not associated with increased basal permeability. The basal SFK activity however was found to contribute to increased sensitivity of the venular endothelium to inflammatory mediator-induced leakage. How SFK activation achieves this is still not well understood. Here, we show that SFK activation renders human dermal microvascular endothelial cells susceptible to low doses of TNF-α. Treatment of DN-Csk-expressing cells with 50 pg/ml TNF-α induced a loss of TEER as well as drastic changes in the actin cytoskeleton and focal adhesion proteins. This synergistic effect was independent of ROCK or NF-κB activity. TNF-α-induced p38 signaling was required for the synergistic effect on barrier function, and activation of the p38 MAPK alone was also able to induce changes in permeability only in monolayers with active SFKs. These results suggest that the activation of endogenous levels of SFK renders the endothelial barrier more susceptible to low, physiologic doses of TNF-α through activation of p38 which leads to a loss of endothelial tight junctions.

  9. Histamine H4 Receptor mediates interleukin-8 and TNF-α release in human mast cells via multiple signaling pathways.

    Science.gov (United States)

    Chen, X-F; Zhang, Z; Dou, X; Li, J-J; Zhang, W; Yu, Y-Y; Yu, B; Yu, B

    2016-01-27

    Histamine, mainly produced by mast cells, is an important inflammatory mediator in immune response. Recently Histamine H4 Receptor (H4R) was also identified in mast cells, from which pro-inflammatory cytokines and chemokines are released. However, the mechanism of how H4R mediates these cytokines and chemokines release in mast cells was still unclear. To further explore the role of H4R in the immune inflammatory response in mast cells, we tested the release of inflammatory cytokine tumor necrosis factor-α (TNF-α), chemokine interleukin-8 (IL-8) and the relevant signaling pathways activated by H4R on LAD2 cells (a human mast cell line). We found that the release of IL-8 and TNF-α were blocked by inhibitors of PI3K, ERK and Ca2+-Calcineurin-NFAT signaling pathways, while the release of these cytokines and chemokines were enhanced by the inhibitor of P38 signaling pathway. However, inhibitors of the JNK and NF-κB signaling pathways had little effect on the expression of the pro-inflammatory mediators. Moreover, activation of the H4R could induce phosphorylation of ERK, p38 and AKT in mast cells. In conclusion, we found that H4R mediates the release of inflammatory cytokine TNF-α and chemokine IL-8 in human mast cells via PI3K, Ca2+-Calcineurin-NFAT and MAPKs signaling pathways.

  10. Crowdsourced assessment of common genetic contribution to predicting anti-TNF treatment response in rheumatoid arthritis

    NARCIS (Netherlands)

    Sieberts, Solveig K.; Zhu, Fan; García-García, Javier; Stahl, Eli; Pratap, Abhishek; Pandey, Gaurav; Pappas, Dimitrios; Aguilar, Daniel; Anton, Bernat; Bonet, Jaume; Eksi, Ridvan; Fornés, Oriol; Guney, Emre; Li, Hongdong; Marín, Manuel Alejandro; Panwar, Bharat; Planas-Iglesias, Joan; Poglayen, Daniel; Cui, Jing; Falcao, Andre O.; Suver, Christine; Hoff, Bruce; Balagurusamy, Venkat S. K.; Dillenberger, Donna; Neto, Elias Chaibub; Norman, Thea; Aittokallio, Tero; Ammad-Ud-Din, Muhammad; Azencott, Chloe-Agathe; Bellón, Víctor; Boeva, Valentina; Bunte, Kerstin; Chheda, Himanshu; Cheng, Lu; Corander, Jukka; Dumontier, Michel; Goldenberg, Anna; Gopalacharyulu, Peddinti; Hajiloo, Mohsen; Hidru, Daniel; Jaiswal, Alok; Kaski, Samuel; Khalfaoui, Beyrem; Khan, Suleiman Ali; Kramer, Eric R.; Marttinen, Pekka; Mezlini, Aziz M.; Molparia, Bhuvan; Pirinen, Matti; Saarela, Janna; Samwald, Matthias; Stoven, Véronique; Tang, Hao; Tang, Jing; Torkamani, Ali; Vert, Jean-Phillipe; Wang, Bo; Wang, Tao; Wennerberg, Krister; Wineinger, Nathan E.; Xiao, Guanghua; Xie, Yang; Yeung, Rae; Zhan, Xiaowei; Zhao, Cheng; Greenberg, Jeff; Kremer, Joel; Michaud, Kaleb; Barton, Anne; Coenen, Marieke; Mariette, Xavier; Miceli, Corinne; Shadick, Nancy; Weinblatt, Michael; de Vries, Niek; Tak, Paul P.; Gerlag, Danielle; Huizinga, Tom W. J.; Kurreeman, Fina; Allaart, Cornelia F.; Louis Bridges, S.; Criswell, Lindsey; Moreland, Larry; Klareskog, Lars; Saevarsdottir, Saedis; Padyukov, Leonid; Gregersen, Peter K.; Friend, Stephen; Plenge, Robert; Stolovitzky, Gustavo; Oliva, Baldo; Guan, Yuanfang; Mangravite, Lara M.; Bridges, S. Louis; Calaza, Manuel; Elmarakeby, Haitham; Heath, Lenwood S.; Long, Quan; Moore, Jonathan D.; Opiyo, Stephen Obol; Savage, Richard S.; Zhu, Jun

    2016-01-01

    Rheumatoid arthritis (RA) affects millions world-wide. While anti-TNF treatment is widely used to reduce disease progression, treatment fails in Bone-third of patients. No biomarker currently exists that identifies non-responders before treatment. A rigorous community-based assessment of the utility

  11. The contribution of adhesion signaling to lactogenesis.

    Science.gov (United States)

    Morrison, Bethanie; Cutler, Mary Lou

    2010-10-01

    The mammary gland undergoes hormonally controlled cycles of pubertal maturation, pregnancy, lactation, and involution, and these processes rely on complex signaling mechanisms, many of which are controlled by cell-cell and cell-matrix adhesion. The adhesion of epithelial cells to the extracellular matrix initiates signaling mechanisms that have an impact on cell proliferation, survival, and differentiation throughout lactation. The control of integrin expression on the mammary epithelial cells, the composition of the extracellular matrix and the presence of secreted matricellular proteins all contribute to essential adhesion signaling during lactogenesis. In vitro and in vivo studies, including the results from genetically engineered mice, have shed light on the regulation of these processes at the cell and tissue level and have led to increased understanding of the essential signaling components that are regulated in temporal and cell specific manner during lactogenesis. Recent studies suggest that a secreted matricellular protein, CTGF/CCN2, may play a role in lactogenic differentiation through binding to β1 integrin complexes, enhancing the production of extracellular matrix components and contributions to cell adhesion signaling.

  12. Regulation of PGE2 signaling pathways and TNF-alpha signaling pathways on the function of bone marrow-derived dendritic cells and the effects of CP-25.

    Science.gov (United States)

    Li, Ying; Sheng, Kangliang; Chen, Jingyu; Wu, Yujing; Zhang, Feng; Chang, Yan; Wu, Huaxun; Fu, Jingjing; Zhang, Lingling; Wei, Wei

    2015-12-15

    This study was to investigate PGE2 and TNF-alpha signaling pathway involving in the maturation and activation of bone marrow dendritic cells (DCs) and the effect of CP-25. Bone marrow DCs were isolated and stimulated by PGE2 and TNF-alpha respectively. The markers of maturation and activation expressed on DCs, such as CD40, CD80, CD83, CD86, MHC-II, and the ability of antigen uptake of DCs were analyzed by flow cytometry. The proliferation of T cells co-cultured with DCs, the signaling pathways of PGE2-EP4-cAMP and TNF-alpha-TRADD-TRAF2-NF-κB in DCs were analyzed. The results showed that both PGE2 and TNF-alpha up-regulated the expressions of CD40, CD80, CD83, CD86, and MHC-II, decreased the antigen uptake of DCs, and DCs stimulated by PGE2 or TNF-alpha could increase T cell proliferation. CP-25 (10(-5), 10(-6), and 10(-7)mol/l) decreased significantly the expressions of CD40, CD80, CD83, CD86 and MHC-II, increased the antigen uptake of DCs, and suppressed T cell proliferation induced by DCs. PGE2 increased the expressions of EP4, NF-κB and down-regulated cAMP level of DCs. TNF-alpha could also up-regulate TNFR1, TRADD, TRAF2, and NF-κB expression of DCs. CP-25 (10(-5), 10(-6), and 10(-7)mol/l) decreased the expressions of EP4 and NF-κB, increased cAMP level in DCs stimulated by PGE2. CP-25 (10(-5), 10(-6), and 10(-7)mol/l) also could down-regulate significantly TNFR1, TRADD, TRAF2, and NF-κB expression in DCs stimulated by TNF-alpha. These results demonstrate that PGE2 and TNF-alpha could enhance DCs functions by mediating PGE2-EP4-cAMP pathway, TNF-alpha-TNFR1-TRADD-TRAF2-NF-κB pathway respectively. CP-25 might inhibit the function of DCs through regulating PGE2-EP4-cAMP and TNF-alpha-TNFR1-TRADD-TRAF2-NF-κB pathways. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. p38 mitogen-activated protein kinase is activated and linked to TNF-alpha signaling in inflammatory bowel disease.

    Science.gov (United States)

    Waetzig, Georg H; Seegert, Dirk; Rosenstiel, Philip; Nikolaus, Susanna; Schreiber, Stefan

    2002-05-15

    Inflammatory bowel diseases (IBD)--Crohn's disease and ulcerative colitis--are relapsing chronic inflammatory disorders which involve genetic, immunological, and environmental factors. The regulation of TNF-alpha, a key mediator in the inflammatory process in IBD, is interconnected with mitogen-activated protein kinase pathways. The aim of this study was to characterize the activity and expression of the four p38 subtypes (p38alpha-delta), c-Jun N-terminal kinases (JNKs), and the extracellular signal-regulated kinases (ERK)1/2 in the inflamed intestinal mucosa. Western blot analysis revealed that p38alpha, JNKs, and ERK1/2 were significantly activated in IBD, with p38alpha showing the most pronounced increase in kinase activity. Protein expression of p38 and JNK was only moderately altered in IBD patients compared with normal controls, whereas ERK1/2 protein was significantly down-regulated. Immunohistochemical analysis of inflamed mucosal biopsies localized the main expression of p38alpha to lamina propria macrophages and neutrophils. ELISA screening of the supernatants of Crohn's disease mucosal biopsy cultures showed that incubation with the p38 inhibitor SB 203580 significantly reduced secretion of TNF-alpha. In vivo inhibition of TNF-alpha by a single infusion of anti-TNF-alpha Ab (infliximab) resulted in a highly significant transient increase of p38alpha activity during the first 48 h after infusion. A significant infliximab-dependent p38alpha activation was also observed in THP-1 myelomonocytic cells. In human monocytes, infliximab enhanced TNF-alpha gene expression, which could be inhibited by SB 203580. In conclusion, p38alpha signaling is involved in the pathophysiology of IBD.

  14. Opposing regulation of the late phase TNF response by mTORC1-IL-10 signaling and hypoxia in human macrophages

    Science.gov (United States)

    Huynh, Linda; Kusnadi, Anthony; Park, Sung Ho; Murata, Koichi; Park-Min, Kyung-Hyun; Ivashkiv, Lionel B.

    2016-01-01

    Tumor necrosis factor (TNF) is best known for inducing a rapid but transient NF-κB-mediated inflammatory response. We investigated later phases of TNF signaling, after the initial transient induction of inflammatory genes has subsided, in primary human macrophages. TNF signaling induced expression of late response genes, including inhibitors of NF-κB and TLR signaling, with delayed and sustained kinetics 6–24 hr after TNF stimulation. A subset of late phase genes was expressed in rheumatoid arthritis synovial macrophages, confirming their expression under chronic inflammatory conditions in vivo. Expression of a subset of late phase genes was mediated by autocrine IL-10, which activated STAT3 with delayed kinetics. Hypoxia, which occurs at sites of infection or inflammation where TNF is expressed, suppressed this IL-10-STAT3 autocrine loop and expression of late phase genes. TNF-induced expression of IL-10 and downstream genes was also dependent on signaling by mTORC1, which senses the metabolic state of cells and is modulated by hypoxia. These results reveal an mTORC1-dependent IL-10-mediated late phase response to TNF by primary human macrophages, and identify suppression of IL-10 responses as a new mechanism by which hypoxia can promote inflammation. Thus, hypoxic and metabolic pathways may modulate TNF responses during chronic inflammation. PMID:27558590

  15. Associations between functional polymorphisms in the NFκB signaling pathway and response to anti-TNF treatment in Danish patients with inflammatory bowel disease

    DEFF Research Database (Denmark)

    Bank, S; Andersen, P S; Burisch, J

    2014-01-01

    -TNF therapy. Using a candidate gene approach, 39 mainly functional single nucleotide polymorphisms (SNPs) in 26 genes regulating inflammation were assessed in 738 prior anti-TNF-naive Danish patients with IBD. The results were analyzed using logistic regression (crude and adjusted for age, gender and smoking...... status). Nineteen functional polymorphisms that alter the NFκB-mediated inflammatory response (TLR2 (rs3804099, rs11938228, rs1816702, rs4696480), TLR4 (rs5030728, rs1554973), TLR9 (rs187084, rs352139), LY96 (MD-2) (rs11465996), CD14 (rs2569190), MAP3K14 (NIK) (rs7222094)), TNFsignaling (TNFA (TNF...

  16. Protein kinase C-α signals P115RhoGEF phosphorylation and RhoA activation in TNF-α-induced mouse brain microvascular endothelial cell barrier dysfunction

    Directory of Open Access Journals (Sweden)

    Deng Xiaolu

    2011-04-01

    Full Text Available Abstract Background Tumor necrosis factor-α (TNF-α, a proinflammatory cytokine, is capable of activating the small GTPase RhoA, which in turn contributes to endothelial barrier dysfunction. However, the underlying signaling mechanisms remained undefined. Therefore, we aimed to determine the role of protein kinase C (PKC isozymes in the mechanism of RhoA activation and in signaling TNF-α-induced mouse brain microvascular endothelial cell (BMEC barrier dysfunction. Methods Bend.3 cells, an immortalized mouse brain endothelial cell line, were exposed to TNF-α (10 ng/mL. RhoA activity was assessed by pull down assay. PKC-α activity was measured using enzyme assasy. BMEC barrier function was measured by transendothelial electrical resistance (TER. p115RhoGEF phosphorylation was detected by autoradiography followed by western blotting. F-actin organization was observed by rhodamine-phalloidin staining. Both pharmacological inhibitors and knockdown approaches were employed to investigate the role of PKC and p115RhoGEF in TNF-α-induced RhoA activation and BMEC permeability. Results We observed that TNF-α induces a rapid phosphorylation of p115RhoGEF, activation of PKC and RhoA in BMECs. Inhibition of conventional PKC by Gö6976 mitigated the TNF-α-induced p115RhoGEF phosphorylation and RhoA activation. Subsequently, we found that these events are regulated by PKC-α rather than PKC-β by using shRNA. In addition, P115-shRNA and n19RhoA (dominant negative mutant of RhoA transfections had no effect on mediating TNF-α-induced PKC-α activation. These data suggest that PKC-α but not PKC-β acts as an upstream regulator of p115RhoGEF phosphorylation and RhoA activation in response to TNF-α. Moreover, depletion of PKC-α, of p115RhoGEF, and inhibition of RhoA activation also prevented TNF-α-induced stress fiber formation and a decrease in TER. Conclusions Taken together, our results show that PKC-α phosphorylation of p115RhoGEF mediates TNF

  17. TNF activity and T cells.

    Science.gov (United States)

    Mehta, Amit K; Gracias, Donald T; Croft, Michael

    2018-01-01

    TNF (tumor necrosis factor) is both a pro-inflammatory and anti-inflammatory cytokine that is central to the development of autoimmune disease, cancer, and protection against infectious pathogens. As well as a myriad other activities, TNF can be a product of T cells and can act on T cells. Here we review old and new data on the importance of TNF produced by T cells and how TNF signaling via TNFR2 may directly impact alternate aspects of T cell biology. TNF can promote the activation and proliferation of naïve and effector T cells, but also can induce apoptosis of highly activated effector T cells, further determining the size of the pathogenic or protective conventional T cell pool. Moreover, TNF can have divergent effects on regulatory T cells. It can both downregulate their suppressive capacity, but also contribute in other instances to their development or accumulation. Biologics that block TNF or stimulate TNFR2 therefore have the potential to strongly modulate the balance between effector T cells and Treg cells which could impact disease in both positive and negative manners. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Involvement of CDX2 in the cross talk between TNF-α and Wnt signaling pathway in the colon cancer cell line Caco-2

    DEFF Research Database (Denmark)

    Coskun, Mehmet; Olsen, Anders Krüger; Bzorek, Michael

    2014-01-01

    Tumor necrosis factor-α (TNF-α) is highly upregulated in inflammation and reduces the expression of the intestinal transcription factor, Caudal-related homeobox transcription factor 2 (CDX2). Wnt/β-catenin signaling is critical for intestinal cell proliferation, but a decreased CDX2 expression ha...... buddings in areas with TNF-α expression in the surrounding inflammatory cells. In vitro studies revealed that TNF-α treatment showed a dose-dependent decrease of CDX2 messenger RNA (mRNA) and protein expression in Caco-2 cells. Inhibition of nuclear factor-kappaB or p38 pathways showed...... targets were significantly elevated in TNF-α-treated Caco-2 cells. These findings were associated with reduced binding of CDX2 to promoter or enhancer regions of APC, AXIN2 and GSK3β. In conclusion, it was found that TNF-α induces the expression of Wnt signaling components through a downregulation...

  19. Raf-1/CK2 and RhoA/ROCK signaling promote TNF-α-mediated endothelial apoptosis via regulating vimentin cytoskeleton.

    Science.gov (United States)

    Yang, Lifeng; Tang, Lian; Dai, Fan; Meng, Guoliang; Yin, Runting; Xu, Xiaole; Yao, Wenjuan

    2017-08-15

    Both RhoA/ROCK and Raf-1/CK2 pathway play essential roles in cell proliferation, apoptosis, differentiation, and multiple other common cellular functions. We previously reported that vimentin is responsible for TNF-α-induced cell apoptosis. Herein, we investigated the regulation of RhoA/ROCK and Raf-1/CK2 signaling on vimentin filaments and endothelial apoptosis mediated by TNF-α. Treatment with TNF-α significantly induced the activation of RhoA and ROCK, and the expression of ROCK1. RhoA deficiency could obviously inhibit ROCK activation and ROCK1 expression induced by TNF-α. Both RhoA deficiency and ROCK activity inhibition (Y-27632) greatly inhibited endothelial apoptosis and preserved cell viability in TNF-α-induced human umbilical vein endothelial cells (HUVECs). Also vimentin phosphorylation and the remodeling of vimentin or phospho-vimentin induced by TNF-α were obviously attenuated by RhoA suppression and ROCK inhibition. TNF-α-mediated vimentin cleavage was significantly inhibited by RhoA suppression and ROCK inhibition through decreasing the activation of caspase3 and 8. Furthermore, TNF-α treatment greatly enhanced the activation of Raf-1. Suppression of Raf-1 or CK2 by its inhibitor (GW5074 or TBB) blocked vimentin phosphorylation, remodeling and endothelial apoptosis, and preserved cell viability in TNF-α-induced HUVECs. However, Raf-1 inhibition showed no significant effect on TNF-α-induced ROCK expression and activation, suggesting that the regulation of Raf-1/CK2 signaling on vimentin was independent of ROCK. Taken together, these results indicate that both RhoA/ROCK and Raf-1/CK2 pathway are responsible for TNF-α-mediated endothelial cytotoxicity via regulating vimentin cytoskeleton. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Localized External Beam Radiation Therapy (EBRT) to the Pelvis Induces Systemic IL-1Beta and TNF-Alpha Production: Role of the TNF-Alpha Signaling in EBRT-Induced Fatigue.

    Science.gov (United States)

    McDonald, Tasha L; Hung, Arthur Y; Thomas, Charles R; Wood, Lisa J

    2016-01-01

    Prostate cancer patients undergoing localized external beam radiation therapy (EBRT) can experience a progressive increase in fatigue, which can affect physical functioning and quality of life. The purpose of this study was to develop a mouse EBRT prostate cancer treatment model with which to determine the role of pro-inflammatory cytokines in the genesis of EBRT-related fatigue. We assessed voluntary wheel-running activity (VWRA) as a proxy for fatigue, food intake and body weight in male C57BL/6 mice undergoing EBRT to the pelvis. In the first experiment, anesthetized male C57BL/6 mice underwent fractionated EBRT to the pelvis for a total dose of 68.2 Gy, thereby mimicking a clinically relevant therapeutic dose and frequency. The day after the last treatment, levels of IL-1β and TNF-α in plasma along with mRNA levels in liver, colon and whole brain were measured. EBRT-induced fatigue resulted in reduced body weight, diminished food intake, and increased plasma and tissue levels of IL-1β and TNF-α. In a follow-up experiment, we used TNF-α-deficient mice to further delineate the role of TNFsignaling in EBRT-induced sickness behavior. EBRT-induced changes in fatigue, food intake and body weight were no different between TNF-α deficient mice and their wild-type counterparts. Taken together our data demonstrate that a clinically relevant localized irradiation of the pelvis induces a systemic IL-1β and TNF-α response and sickness behavior in mice, but the TNFsignaling pathway alone does not independently mediate these effects.

  1. TNF-TNFR2/p75 Signaling Inhibits Early and Increases Delayed Nontargeted Effects in Bone Marrow-derived Endothelial Progenitor Cells*

    Science.gov (United States)

    Sasi, Sharath P.; Song, Jin; Park, Daniel; Enderling, Heiko; McDonald, J. Tyson; Gee, Hannah; Garrity, Brittany; Shtifman, Alexander; Yan, Xinhua; Walsh, Kenneth; Natarajan, Mohan; Kishore, Raj; Goukassian, David A.

    2014-01-01

    TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1–5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3–5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general. PMID:24711449

  2. TNF-α/TNFR1 Signaling is Required for the Full Expression of Acute and Chronic Itch in Mice via Peripheral and Central Mechanisms.

    Science.gov (United States)

    Miao, Xiuhua; Huang, Ya; Liu, Teng-Teng; Guo, Ran; Wang, Bing; Wang, Xue-Long; Chen, Li-Hua; Zhou, Yan; Ji, Ru-Rong; Liu, Tong

    2018-02-01

    Increasing evidence suggests that cytokines and chemokines play crucial roles in chronic itch. In the present study, we evaluated the roles of tumor necrosis factor-alpha (TNF-α) and its receptors TNF receptor subtype-1 (TNFR1) and TNFR2 in acute and chronic itch in mice. Compared to wild-type (WT) mice, TNFR1-knockout (TNFR1-KO) and TNFR1/R2 double-KO (DKO), but not TNFR2-KO mice, exhibited reduced acute itch induced by compound 48/80 and chloroquine (CQ). Application of the TNF-synthesis inhibitor thalidomide and the TNF-α antagonist etanercept dose-dependently suppressed acute itch. Intradermal injection of TNF-α was not sufficient to evoke scratching, but potentiated itch induced by compound 48/80, but not CQ. In addition, compound 48/80 induced TNF-α mRNA expression in the skin, while CQ induced its expression in the dorsal root ganglia (DRG) and spinal cord. Furthermore, chronic itch induced by dry skin was reduced by administration of thalidomide and etanercept and in TNFR1/R2 DKO mice. Dry skin induced TNF-α expression in the skin, DRG, and spinal cord and TNFR1 expression only in the spinal cord. Thus, our findings suggest that TNF-α/TNFR1 signaling is required for the full expression of acute and chronic itch via peripheral and central mechanisms, and targeting TNFR1 may be beneficial for chronic itch treatment.

  3. Central SDF-1/CXCL12 expression and its cardiovascular and sympathetic effects: the role of angiotensin II, TNF-α, and MAP kinase signaling

    Science.gov (United States)

    Wei, Shun-Guang; Zhang, Zhi-Hua; Yu, Yang

    2014-01-01

    The chemokine stromal cell-derived factor-1 (SDF-1/CXCL12) and its receptors are expressed by neurons and glial cells in cardiovascular autonomic regions of the brain, including the hypothalamic paraventricular nucleus (PVN), and contribute to neurohumoral excitation in rats with ischemia-induced heart failure. The present study examined factors regulating the expression of SDF-1 in the PVN and mechanisms mediating its sympatho-excitatory effects. In urethane anesthetized rats, a 4-h intracerebroventricular (ICV) infusion of angiotensin II (ANG II) or tumor necrosis factor-α (TNF-α) in doses that increase mean blood pressure (MBP) and sympathetic drive increased the expression of SDF-1 in PVN. ICV administration of SDF-1 increased the phosphorylation of p44/42 mitogen-activated protein kinase (MAPK), JNK, and p38 MAPK in PVN, along with MBP, heart rate (HR), and renal sympathetic nerve activity (RSNA), but did not affect total p44/42 MAPK, JNK, and p38 MAPK levels. ICV pretreatment with the selective p44/42 MAPK inhibitor PD98059 prevented the SDF-1-induced increases in MBP, HR, and RSNA; ICV pretreatment with the selective JNK and p38 MAPK inhibitors attenuated but did not block these SDF-1-induced excitatory responses. ICV PD98059 also prevented the sympatho-excitatory response to bilateral PVN microinjections of SDF-1. ICV pretreatment with SDF-1 short-hairpin RNA significantly reduced ANG II- and TNF-α-induced phosphorylation of p44/42 MAPK in PVN. These findings identify TNF-α and ANG II as drivers of SDF-1 expression in PVN and suggest that the full expression of their cardiovascular and sympathetic effects depends upon SDF-1-mediated activation of p44/42 MAPK signaling. PMID:25260613

  4. TNF-α Induced by Hepatitis C Virus via TLR7 and TLR8 in Hepatocytes Supports Interferon Signaling via an Autocrine Mechanism

    Science.gov (United States)

    Lee, Jiyoung; Tian, Yongjun; Chan, Stephanie Tze; Kim, Ja Yeon; Cho, Cecilia; Ou, Jing-hsiung James

    2015-01-01

    Invasion by infectious pathogens can elicit a range of cytokine responses from host cells. These cytokines provide the initial host defense mechanism. In this report, we demonstrate that TNF-α, a pro-inflammatory cytokine, can be induced by hepatitis C virus (HCV) in its host cells in a biphasic manner. The initial induction of TNF-α by HCV was prompt and could be blocked by the antibody directed against the HCV E2 envelope protein and by chemicals that inhibit endocytosis, indicating the specificity of endocytic uptake of HCV in this induction. Further studies indicated that the induction of TNF-α was dependent on toll-like receptors 7 and 8 (TLR7/8) but not on other intracellular pattern recognition receptors. Consistently, siRNA-mediated gene silencing of the downstream effectors in the TLR7/8 signaling pathway including MyD88, IRAK1, TRAF6, TAK1 and p65 NF-κB suppressed the expression of TNF-α. The role of p65 NF-κB in the induction of TNF-α via transcriptional up-regulation was further confirmed by the chromatin immunoprecipitation assay. TNF-α induced by HCV could activate its own receptor TNFR1 on hepatocytes to suppress HCV replication. This suppressive effect of TNF-α on HCV was due to its role in supporting interferon signaling, as the suppression of its expression led to the loss of IFNAR2 and impaired interferon signaling and the induction of interferon-stimulated genes. In conclusion, our results indicate that hepatocytes can sense HCV infection via TLR7/8 to induce the expression of TNF-α, which inhibits HCV replication via an autocrine mechanism to support interferon signaling. PMID:26023919

  5. TNF-{alpha} promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Cheng-hu; Cao, Guo-Fan [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Jiang, Qin, E-mail: Jqin710@vip.sina.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Yao, Jin, E-mail: dryaojin@yahoo.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer TNF-{alpha} induces MMP-9 expression and secretion to promote RPE cell migration. Black-Right-Pointing-Pointer MAPK activation is not critical for TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer Akt and mTORC1 signaling mediate TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-{alpha}. -- Abstract: Tumor necrosis factor-alpha (TNF-{alpha}) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-{alpha} promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-{alpha}-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-{alpha}-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-{alpha} promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  6. TNF-α promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

    International Nuclear Information System (INIS)

    Wang, Cheng-hu; Cao, Guo-Fan; Jiang, Qin; Yao, Jin

    2012-01-01

    Highlights: ► TNF-α induces MMP-9 expression and secretion to promote RPE cell migration. ► MAPK activation is not critical for TNF-α-induced MMP-9 expression. ► Akt and mTORC1 signaling mediate TNF-α-induced MMP-9 expression. ► SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-α. -- Abstract: Tumor necrosis factor-alpha (TNF-α) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-α promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-α-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-α-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-α promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  7. Activation of AMPA receptor promotes TNF-α release via the ROS-cSrc-NFκB signaling cascade in RAW264.7 macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Xiu-Li [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Ding, Fan [Office of Scientific R& D, Tsinghua University, Beijing (China); Li, Hui; Tan, Xiao-Qiu [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Liu, Xiao [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Cao, Ji-Min, E-mail: caojimin@126.com [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Gao, Xue, E-mail: longlongnose@163.com [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China)

    2015-05-29

    The relationship between glutamate signaling and inflammation has not been well defined. This study aimed to investigate the role of AMPA receptor (AMPAR) in the expression and release of tumor necrosis factor-alpha (TNF-α) from macrophages and the underlying mechanisms. A series of approaches, including confocal microscopy, immunofluorescency, flow cytometry, ELISA and Western blotting, were used to estimate the expression of AMPAR and downstream signaling molecules, TNF-α release and reactive oxygen species (ROS) generation in the macrophage-like RAW264.7 cells. The results demonstrated that AMPAR was expressed in RAW264.7 cells. AMPA significantly enhanced TNF-α release from RAW264.7 cells, and this effect was abolished by CNQX (AMPAR antagonist). AMPA also induced elevation of ROS production, phosphorylation of c-Src and activation of nuclear factor (NF)-κB in RAW264.7 cells. Blocking c-Src by PP2, scavenging ROS by glutathione (GSH) or inhibiting NF-κB activation by pyrrolidine dithiocarbamate (PDTC) decreased TNF-α production from RAW264.7 cells. We concluded that AMPA promotes TNF-α release in RAW264.7 macrophages likely through the following signaling cascade: AMPAR activation → ROS generation → c-Src phosphorylation → NF-κB activation → TNF-α elevation. The study suggests that AMPAR may participate in macrophage activation and inflammation. - Highlights: • AMPAR is expressed in RAW264.7 macrophages and is upregulated by AMPA stimulation. • Activation of AMPAR stimulates TNF-α release in macrophages through the ROS-cSrc-NFκB signaling cascade. • Macrophage AMPAR signaling may play an important role in inflammation.

  8. Measurement of the contribution of neutrons to hadron calorimeter signals

    International Nuclear Information System (INIS)

    Akchurin, N.; Berntzon, L.; Cardini, A.; Ferrari, R.; Gaudio, G.; Hauptman, J.; Kim, H.; La Rotonda, L.; Livan, M.; Meoni, E.; Paar, H.; Penzo, A.; Pinci, D.; Policicchio, A.; Popescu, S.; Susinno, G.; Roh, Y.; Vandelli, W.; Wigmans, R.

    2007-01-01

    The contributions of neutrons to hadronic signals from the DREAM calorimeter are measured by analyzing the time structure of these signals. The neutrons, which mainly originate from the evaporation stage of nuclear breakup in the hadronic shower development process, contribute through elastic scattering off protons in the plastic scintillating fibers which provide the dE/dx information in this calorimeter. This contribution is characterized by an exponential tail in the pulse shape, with a time constant of ∼25ns. The relative contribution of neutrons to the signals increases with the distance from the shower axis. As expected, the neutrons do not contribute to the DREAM Cherenkov signals

  9. Chronic early childhood exposure to arsenic is associated with a TNF-mediated proteomic signaling response.

    Science.gov (United States)

    Smeester, Lisa; Bommarito, Paige A; Martin, Elizabeth M; Recio-Vega, Rogelio; Gonzalez-Cortes, Tania; Olivas-Calderon, Edgar; Lantz, R Clark; Fry, Rebecca C

    2017-06-01

    Exposure to inorganic arsenic (iAs) in drinking water is a global public health concern and is associated with a range of health outcomes, including immune dysfunction. Children are a particularly sensitive population to the effects of inorganic arsenic, yet the biological mechanisms underlying adverse health outcomes are understudied. Here we used a proteomic approach to examine the effects of iAs exposure on circulating serum protein levels in a cross-sectional children's cohort in Mexico. To identify iAs-associated proteins, levels of total urinary arsenic (U-tAs) and its metabolites were determined and serum proteins assessed for differences in expression. The results indicate an enrichment of Tumor Necrosis Factor-(TNF)-regulated immune and inflammatory response proteins that displayed decreased expression levels in relation to increasing U-tAs. Notably, when analyzed in the context of the proportions of urinary arsenic metabolites in children, the most robust response was observed in relation to the monomethylated arsenicals. This study is among the first serum proteomics assessment in children exposed to iAs. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. TNF-α-Induced NOD2 and RIP2 Contribute to the Up-Regulation of Cytokines Induced by MDP in Monocytic THP-1 Cells.

    Science.gov (United States)

    Chen, Xiaobin; Xiao, Zhilin; Xie, Xiumei; Liu, Xueting; Jiang, Manli; Yuan, Chuang; Yang, Li; Hu, Jinyue

    2017-06-21

    Nucleotide-binding oligomerization domain containing 2 (NOD2)-induced signal transduction and cytokine production is regulated by a number of factors. However, the feedback effect of the pro-inflammatory TNF-α on NOD2-induced inflammation is not fully understood. In this study, we found unexpectedly that TNF-α up-regulated NOD2 ligand MDP-induced production of the CXC chemokines, including CXCL1, 2, and 8, and the pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α, in a dose-dependent manner at both mRNA and protein levels in monocytic THP-1 cells. Though TNF-α induced the up-regulation of ubiquitin-editing enzyme A20, an important negative regulator for Toll-like receptor- and NOD2-induced inflammatory responses, the over-expression of A20 by gene transfer did not reversed MDP-induced production of cytokines, suggested that A20 did not regulate the functions of NOD2 in THP-1 cells. Meanwhile, we found that TNF-α up-regulated NOD2 and its down-stream adaptor protein RIP2 at both mRNA and protein levels. MDP induced the activation of ERK, JNK, p38 and NF-κB, and TNF-α pre-treatment augmented this activation. The results from pharmacological inhibition assay showed that cytokine production was dependent on MAPK signaling. In addition, we found that the pre-treatment of THP-1 cells with MDP down-regulated the mRNA levels of cytokine induced by MDP re-treatment. MDP pre-treatment up-regulated NOD2, but down-regulated RIP2, and down-regulated NOD2 signal transduction induced by MDP re-stimulation. Taking together, these results suggested that TNF-α is a positive regulator for NOD2 functions via up-regulation of NOD2 and its signal adaptor RIP2, and TNF-α-induced A20 does not regulate MDP-induced inflammatory responses in THP-1 cells. J. Cell. Biochem. 9999: 1-10, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. TNF-TNFR2/p75 signaling inhibits early and increases delayed nontargeted effects in bone marrow-derived endothelial progenitor cells.

    Science.gov (United States)

    Sasi, Sharath P; Song, Jin; Park, Daniel; Enderling, Heiko; McDonald, J Tyson; Gee, Hannah; Garrity, Brittany; Shtifman, Alexander; Yan, Xinhua; Walsh, Kenneth; Natarajan, Mohan; Kishore, Raj; Goukassian, David A

    2014-05-16

    TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1-5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3-5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Dynamic Arginine Methylation of Tumor Necrosis Factor (TNF) Receptor-associated Factor 6 Regulates Toll-like Receptor Signaling.

    Science.gov (United States)

    Tikhanovich, Irina; Kuravi, Sudhakiranmayi; Artigues, Antonio; Villar, Maria T; Dorko, Kenneth; Nawabi, Atta; Roberts, Benjamin; Weinman, Steven A

    2015-09-04

    Arginine methylation is a common post-translational modification, but its role in regulating protein function is poorly understood. This study demonstrates that, TNF receptor-associated factor 6 (TRAF6), an E3 ubiquitin ligase involved in innate immune signaling, is regulated by reversible arginine methylation in a range of primary and cultured cells. Under basal conditions, TRAF6 is methylated by the methyltransferase PRMT1, and this inhibits its ubiquitin ligase activity, reducing activation of toll-like receptor signaling. In response to toll-like receptor ligands, TRAF6 is demethylated by the Jumonji domain protein JMJD6. Demethylation is required for maximal activation of NF-κB. Loss of JMJD6 leads to reduced response, and loss of PRMT1 leads to basal pathway activation with subsequent desensitization to ligands. In human primary cells, variations in the PRMT1/JMJD6 ratio significantly correlate with TRAF6 methylation, basal activation of NF-κB, and magnitude of response to LPS. Reversible arginine methylation of TRAF6 by the opposing effects of PRMT1 and JMJD6 is, therefore, a novel mechanism for regulation of innate immune pathways. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. PMS1077 sensitizes TNF-α induced apoptosis in human prostate cancer cells by blocking NF-κB signaling pathway.

    Directory of Open Access Journals (Sweden)

    Jie Shi

    Full Text Available Our previous studies have demonstrated that PMS1077, a platelet-activating factor (PAF antagonist, could induce apoptosis of Raji cells. However, the mechanism of action has not yet been determined. The nuclear transcription factor-kappa B (NF-κB signaling pathway plays a critical role in tumor cell survival, proliferation, invasion, metastasis, and angiogenesis, so we determined the effects of PMS1077 and its structural analogs on tumor necrosis factor-α (TNF-α induced activation of NF-κB signaling. In this study, we found that PMS1077 inhibited TNF-α induced expression of the NF-κB regulated reporter gene in a dose dependent manner. Western blot assay indicated that PMS1077 suppressed the TNF-α induced inhibitor of κB-α (IκB-α phosphorylation, IκB-α degradation, and p65 phosphorylation. PMS1077 consistently blocked TNF-α induced p65 nuclear translocation as demonstrated in the immunofluorescence assay used. Docking studies by molecular modeling predicted that PMS1077 might interact directly with the IκB kinase-β (IKK-β subunit. These results suggested that PMS1077 might suppress the activation of NF-κB by targeting IKK-β involved in the NF-κB signaling pathway. Finally, we showed that PMS1077 sensitized cells to TNF-α induced apoptosis by suppressing the expression of NF-κB regulated anti-apoptotic genes. Our results reveal a novel function of PMS1077 on the NF-κB signaling pathway and imply that PMS1077 can be considered as an anti-tumor lead compound.

  14. Galactose protects hepatocytes against TNF-α-induced apoptosis by promoting activation of the NF-κB signaling pathway in acute liver failure.

    Science.gov (United States)

    Liu, Yanmin; Zhu, Liuluan; Liang, Shuntao; Yao, Shanshan; Li, Rui; Liu, Sanhai; Ma, Yaluan; Zhou, Xiaobing; Zhang, Jinliang; Zeng, Hui; Wang, Xianbo

    2015-05-01

    Saccharides are reported to protect hepatocytes from acute liver injury through distinct mechanisms. To date, the protective role of galactose against acute liver injury induced by lipopolysaccharide (LPS) and D-galactosamine (D-GalN) has been attributed to competition with D-GalN. Here, we showed that in addition to its effects on LPS/D-GalN and tumor necrosis factor alpha (TNF-α)/D-GalN models, galactose improves hepatic injury in mice challenged with LPS alone or TNF-α/actinomycin D. Consistent with this result, galactose enhanced the viability of TNF-α-stimulated Chang Liver and Hu7.5 hepatic cell lines. Specifically, galactose prevented TNF-α-induced apoptosis of hepatocytes through promoting phosphorylation of nuclear factor kappa B (NF-κB) p65. Additionally, galactose enhanced expression of the anti-apoptotic genes, c-IAP1 and A20, and inhibited cleavage of caspase-8 and caspase-3. These findings collectively suggest that galactose prevents TNF-α-induced liver injury through activation of the NF-κB signaling pathway. Considering that monosaccharides protect against liver injury via distinct mechanisms, these compounds may represent a promising clinical approach to treat acute liver failure.

  15. Forward and Reverse Signaling Mediated by Transmembrane Tumor Necrosis Factor-Alpha and TNF Receptor 2: Potential Roles in an Immunosuppressive Tumor Microenvironment

    OpenAIRE

    Qu, Yang; Zhao, Gang; Li, Hui

    2017-01-01

    Tumor necrosis factor-alpha (TNF-α) is a pleiotropic inflammatory cytokine produced mainly by activated macrophages, lymphocytes and other cell types. Two distinct forms of TNF-α have been identified: soluble TNF-α (sTNF-α) and transmembrane TNF-α (mTNF-α). mTNF-α, which is the precursor of sTNF-α, can be cleaved by the TNF-α converting enzyme (TACE) and is released as sTNF-α. sTNF-α binds primarily to TNF receptor 1 (TNFR1) and plays an important role in the inflammatory immune response, whe...

  16. Contributions of Noncanonical Smoothened Signaling During Embryonic Development.

    Science.gov (United States)

    Pandit, Tanushree; Ogden, Stacey K

    2017-01-01

    The Sonic Hedgehog (Shh) signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo), is a G protein-coupled receptor (GPCR) that has been demonstrated to signal through at least two effector routes. The first is a G protein-independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fate during early embryonic development. The second, commonly referred to as the noncanonical Smo signal, induces rapid, transcription-independent responses that are essential for establishing and maintaining distinct cell behaviors during development. Herein, we discuss contributions of this noncanonical route during embryonic development. We also highlight important open questions regarding noncanonical Smo signal route selection during development, and consider implications of noncanonical signal corruption in disease.

  17. Contributions of Noncanonical Smoothened Signaling During Embryonic Development

    Directory of Open Access Journals (Sweden)

    Tanushree Pandit

    2017-10-01

    Full Text Available The Sonic Hedgehog (Shh signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo, is a G protein-coupled receptor (GPCR that has been demonstrated to signal through at least two effector routes. The first is a G protein–independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fate during early embryonic development. The second, commonly referred to as the noncanonical Smo signal, induces rapid, transcription-independent responses that are essential for establishing and maintaining distinct cell behaviors during development. Herein, we discuss contributions of this noncanonical route during embryonic development. We also highlight important open questions regarding noncanonical Smo signal route selection during development, and consider implications of noncanonical signal corruption in disease.

  18. Tumor Necrosis Factor (TNF) Receptor Superfamily Member 1b on CD8+ T Cells and TNF Receptor Superfamily Member 1a on Non-CD8+ T Cells Contribute Significantly to Upper Genital Tract Pathology Following Chlamydial Infection.

    Science.gov (United States)

    Manam, Srikanth; Thomas, Joshua D; Li, Weidang; Maladore, Allison; Schripsema, Justin H; Ramsey, Kyle H; Murthy, Ashlesh K

    2015-06-15

    We demonstrated previously that tumor necrosis factor α (TNF-α)-producing Chlamydia-specific CD8(+) T cells cause oviduct pathological sequelae. In the current study, we used wild-type C57BL/6J (WT) mice with a deficiency in genes encoding TNF receptor superfamily member 1a (TNFR1; TNFR1 knockout [KO] mice), TNF receptor superfamily member 1b (TNFR2; TNFR2 KO mice), and both TNFR1 and TNFR2 (TNFR1/2 double KO [DKO] mice) and mix-match adoptive transfers of CD8(+) T cells to study chlamydial pathogenesis. TNFR1 KO, TNFR2 KO, and TNFR1/2 DKO mice displayed comparable clearance of primary or secondary genital Chlamydia muridarum infection but significantly reduced oviduct pathology, compared with WT animals. The Chlamydia-specific total cellular cytokine response in splenic and draining lymph nodes and the antibody response in serum were comparable between the WT and KO animals. However, CD8(+) T cells from TNFR2 KO mice displayed significantly reduced activation (CD11a expression and cytokine production), compared with TNFR1 KO or WT animals. Repletion of TNFR2 KO mice with WT CD8(+) T cells but not with TNFR2 KO CD8(+) T cells and repletion of TNFR1 KO mice with either WT or TNFR1 KO CD8(+) T cells restored oviduct pathology to WT levels in both KO groups. Collectively, these results demonstrate that TNFR2-bearing CD8(+) T cells and TNFR1-bearing non-CD8(+) T cells contribute significantly to oviduct pathology following genital chlamydial infection. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. MyD88 Signaling Regulates Steady-State Migration of Intestinal CD103+ Dendritic Cells Independently of TNF-α and the Gut Microbiota

    DEFF Research Database (Denmark)

    Hägerbrand, Karin; Westlund, Jessica; Yrlid, Ulf

    2015-01-01

    of both CD103+CD11b+and CD103+CD11b- DCs in the MLN. DC migration was independent of caspase-1, which is responsible for the inflammasomedependentproteolytic activation of IL-1 cytokine family members, and was not affected by treatment with broad-spectrumantibiotics. Consistent with the latter finding....... Similarly,TLR signaling through the adaptor molecule Toll/IL-1R domain-containing adapter inducing IFN-b and downstream productionof type I IFN were not required for steady-state CD103+ DC migration. Taken together, our results demonstrate that MyD88 signaling in DCs, independently of the microbiota and TNF...

  20. 3D-Printed Atsttrin-Incorporated Alginate/Hydroxyapatite Scaffold Promotes Bone Defect Regeneration with TNF/TNFR Signaling Involvement.

    Science.gov (United States)

    Wang, Quan; Xia, Qingqing; Wu, Yan; Zhang, Xiaolei; Wen, Feiqiu; Chen, Xiaowen; Zhang, Shufang; Heng, Boon Chin; He, Yong; Ouyang, Hong-Wei

    2015-08-05

    High expression levels of pro-inflammatory tumor necrosis factor (TNF)-α within bone defects can decelerate and impair bone regeneration. However, there are few available bone scaffolds with anti-inflammatory function. The progranulin (PGRN)-derived engineered protein, Atsttrin, is known to exert antagonistic effects on the TNF-α function. Hence, this study investigates whether 3D-printed Atsttrin-incorporated alginate(Alg)/hydroxyapatite(nHAp) scaffolds can facilitate bone healing through affecting the TNF/TNFR signaling. A 3D bioprinting system is used to fabricate Atsttrin-Alg/nHAp composite scaffolds, and the Atsttrin release from this scaffold is characterized, followed by evaluation of its efficacy on bone regeneration both in vitro and in vivo. The 3D-printed Atsttrin-Alg/nHAp scaffold exhibits a precisely defined structure, can sustain Atsttrin release for at least 5 days, has negligible cytotoxicity, and supports cell adhesion. Atsttrin can also attenuate the suppressive effects of TNF-α on BMP-2-induced osteoblastic differentiation in vitro. The 3D-printed Atsttrin-Alg/nHAp scaffold significantly reduces the number of TNF-α positive cells within wound sites, 7 days after post-calvarial defect surgery. Additionally, histological staining and X-ray scanning results also show that the 3D-printed Atsttrin-Alg/nHAp scaffold enhances the regeneration of mice calvarial bone defects. These findings thus demonstrate that the precise structure and anti-inflammatory properties of 3D-printed Atsttrin-Alg/nHAp scaffolds may promote bone defect repair. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. TRAF2 regulates TNF and NF-κB signalling to suppress apoptosis and skin inflammation independently of Sphingosine kinase 1

    Science.gov (United States)

    Etemadi, Nima; Chopin, Michael; Anderton, Holly; Tanzer, Maria C; Rickard, James A; Abeysekera, Waruni; Hall, Cathrine; Spall, Sukhdeep K; Wang, Bing; Xiong, Yuquan; Hla, Timothy; Pitson, Stuart M; Bonder, Claudine S; Wong, Wendy Wei-Lynn; Ernst, Matthias; Smyth, Gordon K; Vaux, David L; Nutt, Stephen L; Nachbur, Ueli; Silke, John

    2015-01-01

    TRAF2 is a component of TNF superfamily signalling complexes and plays an essential role in the regulation and homeostasis of immune cells. TRAF2 deficient mice die around birth, therefore its role in adult tissues is not well-explored. Furthermore, the role of the TRAF2 RING is controversial. It has been claimed that the atypical TRAF2 RING cannot function as a ubiquitin E3 ligase but counterclaimed that TRAF2 RING requires a co-factor, sphingosine-1-phosphate, that is generated by the enzyme sphingosine kinase 1, to function as an E3 ligase. Keratinocyte-specific deletion of Traf2, but not Sphk1 deficiency, disrupted TNF mediated NF-κB and MAP kinase signalling and caused epidermal hyperplasia and psoriatic skin inflammation. This inflammation was driven by TNF, cell death, non-canonical NF-κB and the adaptive immune system, and might therefore represent a clinically relevant model of psoriasis. TRAF2 therefore has essential tissue specific functions that do not overlap with those of Sphk1. DOI: http://dx.doi.org/10.7554/eLife.10592.001 PMID:26701909

  2. A TNF-p100 pathway subverts noncanonical NF-κB signaling in inflamed secondary lymphoid organs.

    Science.gov (United States)

    Mukherjee, Tapas; Chatterjee, Budhaditya; Dhar, Atika; Bais, Sachendra S; Chawla, Meenakshi; Roy, Payel; George, Anna; Bal, Vineeta; Rath, Satyajit; Basak, Soumen

    2017-12-01

    Lymphotoxin-beta receptor (LTβR) present on stromal cells engages the noncanonical NF-κB pathway to mediate RelB-dependent expressions of homeostatic chemokines, which direct steady-state ingress of naïve lymphocytes to secondary lymphoid organs (SLOs). In this pathway, NIK promotes partial proteolysis of p100 into p52 that induces nuclear translocation of the RelB NF-κB heterodimers. Microbial infections often deplete homeostatic chemokines; it is thought that infection-inflicted destruction of stromal cells results in the downregulation of these chemokines. Whether inflammation per se also regulates these processes remains unclear. We show that TNF accumulated upon non-infectious immunization of mice similarly downregulates the expressions of these chemokines and consequently diminishes the ingress of naïve lymphocytes in inflamed SLOs. Mechanistically, TNF inactivated NIK in LTβR-stimulated cells and induced the synthesis of Nfkb2 mRNA encoding p100; these together potently accumulated unprocessed p100, which attenuated the RelB activity as inhibitory IκBδ. Finally, a lack of p100 alleviated these TNF-mediated inhibitions in inflamed SLOs of immunized Nfkb2 -/- mice. In sum, we reveal that an inhibitory TNF-p100 pathway modulates the adaptive compartment during immune responses. © 2017 The Authors.

  3. PTEN enhances TNF-induced apoptosis through modulation of nuclear factor-κB signaling pathway in human glioma cells

    International Nuclear Information System (INIS)

    Koul, Dimpy; Takada, Yasunari; Shen, Ruijun; Aggarwal, Bharat B.; Yung, W.K. Alfred

    2006-01-01

    The PTEN tumor suppressor gene modulates cell growth and survival known to be regulated by the activation of the transcription factor NFκB, suggesting PTEN might affect the NFκB activation pathway. We found that PTEN inhibited NFκB activation induced by TNF. The suppression of NFκB activation correlated with sequential inhibition of the tumor necrosis factor-induced expression of NFκB-regulated anti-apoptotic (IAP1, IAP2, Bcl-2, Bcl-xL, cFLIP, Bfl-1/A1, and survivin) gene products. Downregulation of the antiapoptotic genes by PTEN increased TNF-induced apoptosis, as indicated by caspase activation, TUNEL, annexin staining, and esterase assay. We conclude that the ectopic expression of PTEN enhances TNF-induced apoptosis and downregulates the proliferation of glioma cells through the suppression of various molecules including NFκB, and various mediators of cellular survival and proliferation, and that this targets might be essential for its central role in the growth and survival of glioma cancer cells

  4. Autoimmune regulator (AIRE) contributes to Dectin-1-induced TNF-α production and complexes with caspase recruitment domain-containing protein 9 (CARD9), spleen tyrosine kinase (Syk), and Dectin-1.

    Science.gov (United States)

    Pedroza, Luis A; Kumar, Vipul; Sanborn, Keri B; Mace, Emily M; Niinikoski, Harri; Nadeau, Kari; Vasconcelos, Dewton de Moraes; Perez, Elena; Jyonouchi, Soma; Jyonouchi, Harumi; Banerjee, Pinaki P; Ruuskanen, Olli; Condino-Neto, Antonio; Orange, Jordan S

    2012-02-01

    Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome is a complex immunologic disease caused by mutation of the autoimmune regulator (AIRE) gene. Autoimmunity in patients with APECED syndrome has been shown to result from deficiency of AIRE function in transcriptional regulation of thymic peripheral tissue antigens, which leads to defective T-cell negative selection. Candidal susceptibility in patients with APECED syndrome is thought to result from aberrant adaptive immunity. To determine whether AIRE could function in anticandidal innate immune signaling, we investigated an extrathymic role for AIRE in the immune recognition of β-glucan through the Dectin-1 pathway, which is required for defense against Candida species. Innate immune signaling through the Dectin-1 pathway was assessed in both PBMCs from patients with APECED syndrome and a monocytic cell line. Subcellular localization of AIRE was assessed by using confocal microscopy. PBMCs from patients with APECED syndrome had reduced TNF-α responses after Dectin-1 ligation but in part used a Raf-1-mediated pathway to preserve function. In the THP-1 human monocytic cell line, reducing AIRE expression resulted in significantly decreased TNF-α release after Dectin-1 ligation. AIRE formed a transient complex with the known Dectin-1 pathway components phosphorylated spleen tyrosine kinase and caspase recruitment domain-containing protein 9 after receptor ligation and localized with Dectin-1 at the cell membrane. AIRE can participate in the Dectin-1 signaling pathway, indicating a novel extrathymic role for AIRE and a defect that likely contributes to fungal susceptibility in patients with APECED syndrome. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  5. Anti-inflammatory mechanism of ulinastatin: Inhibiting the hyperpermeability of vascular endothelial cells induced by TNF-α via the RhoA/ROCK signal pathway.

    Science.gov (United States)

    Wei, Fu; Liu, Siyi; Luo, Li; Gu, Nina; Zeng, Yan; Chen, Xiaoying; Xu, Shan; Zhang, Dan

    2017-05-01

    Ulinastatin reduces the high permeability of vascular endothelial cells induced by tumor necrosis factor alpha (TNF-α). This study investigated the molecular mechanism behind this effect, with the aim of understanding the action of ulinastatin in sepsis therapy and exploring novel therapeutic strategies for sepsis patients. A TNF-α treated human umbilical vein endothelial cell line (EA.hy926) was employed as an inflammation model. Horseradish peroxidase permeability assays and an epithelial voltmeter method were used to measure the permeability of EA.hy926 cells. Immunocytochemistry was used to assay the expression of p-MYPT1 and the distribution and morphology of F-actin; the expression of the key molecules related to vascular endothelial permeability (RhoA, ROCK2, MYPT1, p-MYPT1 and VE-cadherin) was detected by immunocytochemistry assays, western blotting and quantitative real-time polymerase chain reaction. After incubation with TNF-α or septic serum, the transendothelial electrical resistance of EA.hy926 cells decreased and the permeability of the cells increased significantly (all PTNF-α (PTNF-α and ulinastatin, compared with normal EA.hy926 cells, overexpression of RhoA upregulated expression of RhoA, ROCK2 and p-MYPT1, downregulated expression of VE-cadherin, and restored the hyperpermeability of vascular endothelial cells due to TNF-α treatment (PTNF-α. This inhibitory effect of ulinastatin may be related to the RhoA/ROCK signaling pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Elevated placental adenosine signaling contributes to the pathogenesis of preeclampsia.

    Science.gov (United States)

    Iriyama, Takayuki; Sun, Kaiqi; Parchim, Nicholas F; Li, Jessica; Zhao, Cheng; Song, Anren; Hart, Laura A; Blackwell, Sean C; Sibai, Baha M; Chan, Lee-Nien L; Chan, Teh-Sheng; Hicks, M John; Blackburn, Michael R; Kellems, Rodney E; Xia, Yang

    2015-02-24

    Preeclampsia is a prevalent hypertensive disorder of pregnancy and a leading cause of maternal and neonatal morbidity and mortality worldwide. This pathogenic condition is speculated to be caused by placental abnormalities that contribute to the maternal syndrome. However, the specific factors and signaling pathways that lead to impaired placentas and maternal disease development remain elusive. Using 2 independent animal models of preeclampsia (genetically engineered pregnant mice with elevated adenosine exclusively in placentas and a pathogenic autoantibody-induced preeclampsia mouse model), we demonstrated that chronically elevated placental adenosine was sufficient to induce hallmark features of preeclampsia, including hypertension, proteinuria, small fetuses, and impaired placental vasculature. Genetic and pharmacological approaches revealed that elevated placental adenosine coupled with excessive A₂B adenosine receptor (ADORA2B) signaling contributed to the development of these features of preeclampsia. Mechanistically, we provided both human and mouse evidence that elevated placental CD73 is a key enzyme causing increased placental adenosine, thereby contributing to preeclampsia. We determined that elevated placental adenosine signaling is a previously unrecognized pathogenic factor for preeclampsia. Moreover, our findings revealed the molecular basis underlying the elevation of placental adenosine and the detrimental role of excess placental adenosine in the pathophysiology of preeclampsia, and thereby, we highlight novel therapeutic targets. © 2014 American Heart Association, Inc.

  7. GAPDH Binding to TNF-α mRNA Contributes to Posttranscriptional Repression in Monocytes: A Novel Mechanism of Communication between Inflammation and Metabolism.

    Science.gov (United States)

    Millet, Patrick; Vachharajani, Vidula; McPhail, Linda; Yoza, Barbara; McCall, Charles E

    2016-03-15

    Expression of the inflammatory cytokine TNF is tightly controlled. During endotoxin tolerance, transcription of TNF mRNA is repressed, although not entirely eliminated. Production of TNF cytokine, however, is further controlled by posttranscriptional regulation. In this study, we detail a mechanism of posttranscriptional repression of TNF mRNA by GAPDH binding to the TNF 3' untranslated region. Using RNA immunoprecipitation, we demonstrate that GAPDH-TNF mRNA binding increases when THP-1 monocytes are in a low glycolysis state, and that this binding can be reversed by knocking down GAPDH expression or by increasing glycolysis. We show that reducing glycolysis decreases TNF mRNA association with polysomes. We demonstrate that GAPDH-TNF mRNA binding results in posttranscriptional repression of TNF and that the TNF mRNA 3' untranslated region is sufficient for repression. Finally, after exploring this model in THP-1 cells, we demonstrate this mechanism affects TNF expression in primary human monocytes and macrophages. We conclude that GAPDH-TNF mRNA binding regulates expression of TNF based on cellular metabolic state. We think this mechanism has potentially significant implications for treatment of various immunometabolic conditions, including immune paralysis during septic shock. Copyright © 2016 by The American Association of Immunologists, Inc.

  8. Evidence that LPS-reactive arthritis in rats depends on the glial activity and the fractalkine-TNFsignaling in the spinal cord.

    Science.gov (United States)

    Bressan, Elisângela; Peres, Kaite Cristiane; Tonussi, Carlos Rogério

    2012-02-01

    It is known that primary afferent central terminal sensitization can influence peripheral inflammation, however, it remains to be understood whether spinal cord glia can also contribute to this process. Our aim was to investigate the effect of spinal cord glia inhibition on the pathogenesis of LPS-induced knee-joint monoarthritis in rats and also to investigate the role of fractalkine and TNF-α. LPS was injected into the knee-joint previously primed with carrageenan to cause articular incapacitation, edema, synovial leukocyte infiltration, and GFAP and CD11b/c spinal immunoreactivity (glia-IR) increase. Articular edema was more sensitive to the inhibition by intrathecal fluorocitrate and minocycline than nociception and synovial leukocyte content. The higher doses of both drugs were ineffective when given by intraperitoneal route. Corticosteroid synthesis inhibition by aminoglutethimide did not change the glia inhibitors effect. The inhibitory effect of the dorsal root potential inhibitor, furosemide, was not additive to that caused by fluorocitrate and minocycline. Intrathecal anti-fractalkine and anti-TNF-α inhibited edema, nociception, and synovial leukocytes, while fractalkine caused the opposite effects. The fractalkine effect was inhibited by fluorocitrate and anti-TNF-α. Finally, fluorocitrate, minocycline and anti-fractalkine attenuated, but fractalkine increased, GFAP and CD11b/c IR. The evidence reported herein supports the hypothesis that spinal fractalkine release is involved in glia activation, which via the spinal release of TNF-α, seems to be involved in the development and maintenance of this arthritis model. A possible modulation of the dorsal root reflexes is discussed. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. PTH Signaling During Exercise Contributes to Bone Adaptation†

    Science.gov (United States)

    Gardinier, Joseph D.; Mohamed, Fatma; Kohn, David H.

    2016-01-01

    Improving the structural integrity of bone reduces fracture risk and development of osteoporosis later in life. Exercise can increase the mechanical properties of bone, and this increase is often attributed to the dynamic loading created during exercise. However, the increase in systemic PTH levels during exercise gives reason to hypothesize that PTH signaling also regulates bone adaptation in response to exercise. Therefore, the first aim of this study was to establish the impact PTH signaling has on bone adaptation during exercise by inhibiting PTH signaling with PTH(7-34) and the second aim was to determine if increasing PTH levels during exercise with PTH(1-34) can augment bone adaptation. Thirty minutes after a single bout of running on a treadmill, mice exhibited a two-fold increase in systemic PTH levels. Under the same exercise regimen, the influence of PTH signaling on bone adaptation during exercise was then evaluated in mice after 21 consecutive days of exercise and treatment with PTH(7-34), PTH(1-34), or vehicle. Exercise alone caused a significant increase in trabecular bone volume with adaptation to a more plate-like structure, which was inhibited with PTH(7-34) during exercise. Changes in structural and tissue-level mechanical properties during exercise occurred in the absence of significant changes to cortical bone geometry. Inhibition of PTH signaling during exercise attenuated the changes in structural-level mechanical properties, but not tissue-level properties. Enhanced PTH signaling during exercise with PTH(1-34) increased trabecular and cortical bone volume, but had little effect on the structural and tissue-level mechanical properties compared to exercise alone. Our study is the first to demonstrate that bone adaptation during exercise is not only a function of the dynamic loading, but also PTH release, and that PTH signaling contributes differently at the structural and tissue-levels. PMID:25529455

  10. PTH Signaling During Exercise Contributes to Bone Adaptation.

    Science.gov (United States)

    Gardinier, Joseph D; Mohamed, Fatma; Kohn, David H

    2015-06-01

    Improving the structural integrity of bone reduces fracture risk and development of osteoporosis later in life. Exercise can increase the mechanical properties of bone, and this increase is often attributed to the dynamic loading created during exercise. However, the increase in systemic parathyroid hormone (PTH) levels during exercise gives reason to hypothesize that PTH signaling also regulates bone adaptation in response to exercise. Therefore, the first aim of this study was to establish the impact PTH signaling has on bone adaptation during exercise by inhibiting PTH signaling with PTH(7-34); the second aim was to determine whether increasing PTH levels during exercise with PTH(1-34) can augment bone adaptation. Thirty minutes after a single bout of running on a treadmill, mice exhibited a twofold increase in systemic PTH levels. Under the same exercise regimen, the influence of PTH signaling on bone adaptation during exercise was then evaluated in mice after 21 consecutive days of exercise and treatment with PTH(7-34), PTH(1-34), or vehicle. Exercise alone caused a significant increase in trabecular bone volume with adaptation to a more platelike structure, which was inhibited with PTH(7-34) during exercise. Changes in structural-level and tissue-level mechanical properties during exercise occurred in the absence of significant changes to cortical bone geometry. Inhibition of PTH signaling during exercise attenuated the changes in structural-level mechanical properties, but not tissue-level properties. Enhanced PTH signaling during exercise with PTH(1-34) increased trabecular and cortical bone volume, but had little effect on the structural-level and tissue-level mechanical properties compared to exercise alone. Our study is the first to demonstrate that bone adaptation during exercise is not only a function of dynamic loading, but also PTH release, and that PTH signaling contributes differently at the structural and tissue levels. © 2015 American Society

  11. Astrocyte galectin-9 potentiates microglial TNF secretion.

    Science.gov (United States)

    Steelman, Andrew J; Li, Jianrong

    2014-08-27

    Aberrant neuroinflammation is suspected to contribute to the pathogenesis of myriad neurological diseases. As such, determining the pathways that promote or inhibit glial activation is of interest. Activation of the surface glycoprotein T-cell immunoglobulin and mucin-domain containing protein 3 (Tim-3) by the lectin galectin-9 has been implicated in promoting innate immune cell activation by potentiating or synergizing toll-like receptor (TLR) signaling. In the present study we examined the role of the Tim-3/galectin-9 pathway in glial activation in vitro. Primary monocultures of microglia or astrocytes, co-cultures containing microglia and astrocytes, and mixed glial cultures consisting of microglia, astrocytes and oligodendrocytes were stimulated with poly(I:C) or LPS, and galectin-9 up-regulation was determined. The effect of endogenous galectin-9 production on microglial activation was examined using cultures from wild-type and Lgals9 null mice. The ability for recombinant galectin-9 to promote microglia activation was also assessed. Tim-3 expression on microglia and BV2 cells was examined by qPCR and flow cytometry and its necessity in transducing the galectin-9 signal was determined using a Tim-3 specific neutralizing antibody or recombinant soluble Tim-3. Astrocytes potentiated TNF production from microglia following TLR stimulation. Poly(I:C) stimulation increased galectin-9 expression in microglia and microglial-derived factors promoted galectin-9 up-regulation in astrocytes. Astrocyte-derived galectin-9 in turn enhanced microglial TNF production. Similarly, recombinant galectin-9 enhanced poly(I:C)-induced microglial TNF and IL-6 production. Inhibition of Tim-3 did not alter TNF production in mixed glial cultures stimulated with poly(I:C). Galectin-9 functions as an astrocyte-microglia communication signal and promotes cytokine production from microglia in a Tim-3 independent manner. Activation of CNS galectin-9 likely modulates neuroinflammatory

  12. A novel synthetic analogue of ω-3 17,18-epoxyeicosatetraenoic acid activates TNF receptor-1/ASK1/JNK signaling to promote apoptosis in human breast cancer cells.

    Science.gov (United States)

    Dyari, Herryawan Ryadi Eziwar; Rawling, Tristan; Chen, Yongjuan; Sudarmana, William; Bourget, Kirsi; Dwyer, Julie M; Allison, Sarah E; Murray, Michael

    2017-12-01

    A saturated analog of the cytochrome P450-mediated ω-3-17,18-epoxide of ω-3-eicosapentaenoic acid (C20E) activated apoptosis in human triple-negative MDA-MB-231 breast cancer cells. This study evaluated the apoptotic mechanism of C20E. Increased cytosolic cytochrome c expression and altered expression of pro- and antiapoptotic B-cell lymphoma-2 proteins indicated activation of the mitochondrial pathway. Caspase-3 activation by C20E was prevented by pharmacological inhibition and silencing of the JNK and p38 MAP kinases (MAPK), upstream MAPK kinases MKK4 and MKK7, and the upstream MAPK kinase kinase apoptosis signal-regulating kinase 1 (ASK1). Silencing of the death receptor TNF receptor 1 (TNFR1), but not Fas, DR4, or DR5, and the adapters TRADD and TNF receptor-associated factor 2, but not Fas-associated death domain, prevented C20E-mediated apoptosis. B-cell lymphoma-2 homology 3-interacting domain death agonist (Bid) cleavage by JNK/p38 MAPK linked the extrinsic and mitochondrial pathways of apoptosis. In further studies, an antibody against the extracellular domain of TNFR1 prevented apoptosis by TNF-α but not C20E. These findings suggest that C20E acts intracellularly at TNFR1 to activate ASK1-MKK4/7-JNK/p38 MAPK signaling and to promote Bid-dependent mitochondrial disruption and apoptosis. In in vivo studies, tumors isolated from C20E-treated nu/nu mice carrying MDA-MB-231 xenografts showed increased TUNEL staining and decreased Ki67 staining, reflecting increased apoptosis and decreased proliferation, respectively. ω-3-Epoxy fatty acids like C20E could be incorporated into treatments for triple-negative breast cancers.-Dyari, H. R. E., Rawling, T., Chen, Y., Sudarmana, W., Bourget, K., Dwyer, J. M., Allison, S. E., Murray, M. A novel synthetic analogue of ω-3 17,18-epoxyeicosatetraenoic acid activates TNF receptor-1/ASK1/JNK signaling to promote apoptosis in human breast cancer cells. © FASEB.

  13. The contribution of Teflon to the thermoluminescent signal

    International Nuclear Information System (INIS)

    German, U.; Weinstein, M.; Ben-Shachar; Pelled, O.

    1997-01-01

    In the thermoluminescent method, we are measuring the light emitted by the phosphor (called TL output), irradiated previously by ionizing radiation. There are several other effects, which can cause emission of light similar to the TL output, which can affect the results of personnel and environmental dosimetry, especially for low doses. It is described several such effects, as illumination of lithium fluoride thermoluminescent dosimeters, particularly with ultraviolet wavelengths. It was presented that the results of the glow curve of LiF:Mg,Ti chips, after exposure to different non-ionizing radiation (u.v., microwave, electric sparks). It has reviewed the reports of light induced signals in LiF ( I > 380 nm). These effects cause dosimeters to emit TL similar to that caused by exposure to ionizing These effects cause dosimeters to emit TL similar to that caused by exposure to ionizing radiation.A signal is received when heating teflon sheets, which contributes to the TL signal. It was pointed out that the light induced TL emission from the teflon has a glow peak 120 degree C. The purpose of the present work was to perform a quantitative evaluation of the glow contributed by the teflon used in the TLD cards employed by us Harshaw - TLD 100 for different storage conditions. (authors)

  14. Tie2 signaling cooperates with TNF to promote the pro-inflammatory activation of human macrophages independently of macrophage functional phenotype.

    Directory of Open Access Journals (Sweden)

    Samuel García

    Full Text Available Angiopoietin (Ang -1 and -2 and their receptor Tie2 play critical roles in regulating angiogenic processes during development, homeostasis, tumorigenesis, inflammation and tissue repair. Tie2 signaling is best characterized in endothelial cells, but a subset of human and murine circulating monocytes/macrophages essential to solid tumor formation express Tie2 and display immunosuppressive properties consistent with M2 macrophage polarization. However, we have recently shown that Tie2 is strongly activated in pro-inflammatory macrophages present in rheumatoid arthritis patient synovial tissue. Here we examined the relationship between Tie2 expression and function during human macrophage polarization. Tie2 expression was observed under all polarization conditions, but was highest in IFN-γ and IL-10 -differentiated macrophages. While TNF enhanced expression of a common restricted set of genes involved in angiogenesis and inflammation in GM-CSF, IFN-γ and IL-10 -differentiated macrophages, expression of multiple chemokines and cytokines, including CXCL3, CXCL5, CXCL8, IL6, and IL12B was further augmented in the presence of Ang-1 and Ang-2, via Tie2 activation of JAK/STAT signaling. Conditioned medium from macrophages stimulated with Ang-1 or Ang-2 in combination with TNF, sustained monocyte recruitment. Our findings suggest a general role for Tie2 in cooperatively promoting the inflammatory activation of macrophages, independently of polarization conditions.

  15. Defective Suppressor of Cytokine Signaling 1 Signaling Contributes to the Pathogenesis of Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Huixia Wang

    2017-10-01

    Full Text Available Systemic lupus erythematosus (SLE is a complex autoimmune disease involving injuries in multiple organs and systems. Exaggerated inflammatory responses are characterized as end-organ damage in patients with SLE. Although the explicit pathogenesis of SLE remains unclear, increasing evidence suggests that dysregulation of cytokine signals contributes to the progression of SLE through the Janus kinase/signal transducer and activator of transcription (STAT signaling pathway. Activated STAT proteins translocate to the cell nucleus and induce transcription of target genes, which regulate downstream cytokine production and inflammatory cell infiltration. The suppressor of cytokine signaling 1 (SOCS1 is considered as a classical inhibitor of cytokine signaling. Recent studies have demonstrated that SOCS1 expression is decreased in patients with SLE and in murine lupus models, and this negatively correlates with the magnitude of inflammation. Dysregulation of SOCS1 signals participates in various pathological processes of SLE such as hematologic abnormalities and autoantibody generation. Lupus nephritis is one of the most serious complications of SLE, and it correlates with suppressed SOCS1 signals in renal tissues. Moreover, SOCS1 insufficiency affects the function of several other organs, including skin, central nervous system, liver, and lungs. Therefore, SOCS1 aberrancy contributes to the development of both systemic and local inflammation in SLE patients. In this review, we discuss recent studies regarding the roles of SOCS1 in the pathogenesis of SLE and its therapeutic implications.

  16. Conditional ablation of myeloid TNF increases lesion volume after experimental stroke in mice, possibly via altered ERK1/2 signaling

    DEFF Research Database (Denmark)

    Clausen, Bettina Hjelm; Degn, Matilda; Sivasaravanaparan, Mithula

    2016-01-01

    Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (LysMcreTNF(fl/fl))......Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (Lys......McreTNF(fl/fl)) in which the TNF gene was deleted in cells of the myeloid lineage, including microglia. The deletion reduced secreted TNF levels in lipopolysaccharide-stimulated cultured primary microglia by ~93%. Furthermore, phosphorylated-ERK/ERK ratios were significantly decreased in naïve LysMcreTNF(fl/fl) mice...... compared to littermates (TNFfl/fl). In naïve LysMcreTNF(fl/fl) mice cytokine levels were low and comparable to littermates. At 6 hours, TNF producing microglia were reduced by 56% in the ischemic cortex in LysMcreTNF(fl/fl) mice compared to littermate mice, whereas no TNF(+) leukocytes were detected. At 24...

  17. Cordycepin Inhibits Lipopolysaccharide (LPS-Induced Tumor Necrosis Factor (TNF-α Production via Activating AMP-Activated Protein Kinase (AMPK Signaling

    Directory of Open Access Journals (Sweden)

    Jian-Li Zhang

    2014-07-01

    Full Text Available Tumor necrosis factor (TNF-α is elevated during the acute phase of Kawasaki disease (KD, which damages vascular endothelial cells to cause systemic vasculitis. In the current study, we investigated the potential role of cordycepin on TNFα expression in both lipopolysaccharide (LPS-stimulated macrophages and ex vivo cultured peripheral blood mononuclear cells (PBMCs of KD patients. We found that cordycepin significantly suppressed LPS-induced TNFα expression and production in mouse macrophages (RAW 264.7 cells and bone marrow-derived macrophages (BMDMs. Meanwhile, cordycepin alleviated TNFα production in KD patients’ PBMCs. PBMCs from healthy controls had a much lower level of basal TNF-α content than that of KD patients. LPS-induced TNF-α production in healthy controls’ PBMCs was also inhibited by cordycepin. For the mechanism study, we discovered that cordycepin activated AMP-activated protein kinase (AMPK signaling in both KD patients’ PBMCs and LPS-stimulated macrophages, which mediated cordycepin-induced inhibition against TNFα production. AMPK inhibition by its inhibitor (compound C or by siRNA depletion alleviated cordycepin’s effect on TNFα production. Further, we found that cordycepin inhibited reactive oxygen species (ROS production and nuclear factor kappa B (NF-κB activation in LPS-stimulate RAW 264.7 cells or healthy controls’ PBMCs. PBMCs of KD patients showed higher basal level of ROS and NF-κB activation, which was also inhibited by cordycepin co-treatment. In conclusion, our data showed that cordycepin inhibited TNFα production, which was associated with AMPK activation as well as ROS and NF-κB inhibition. The results of this study should have significant translational relevance in managing this devastating disease.

  18. Tristetraprolin Down-Regulation Contributes to Persistent TNF-Alpha Expression Induced by Cigarette Smoke Extract through a Post-Transcriptional Mechanism

    Science.gov (United States)

    Cheng, Ming-Liang; Zhang, Quan; Mu, Mao; Li, Hong; Luo, Yuan; Liang, Yue-Dong; Luo, Xin-Hua; Gao, Chang-Qing; Jackson, Patricia L.; Wells, J. Michael; Zhou, Yong; Hu, Meng; Cai, Guoqiang; Thannickal, Victor J.; Steele, Chad; Blalock, J. Edwin; Han, Xiaosi; Chen, Ching-Yi; Ding, Qiang

    2016-01-01

    Rationale Tumor necrosis factor-alpha (TNF-α) is a potent pro-inflammatory mediator and its expression is up-regulated in chronic obstructive pulmonary disease (COPD). Tristetraprolin (TTP) is implicated in regulation of TNF-α expression; however, whether TTP is involved in cigarette smoke-induced TNF-α expression has not been determined. Methods TTP expression was examined by western blot analysis in murine alveolar macrophages and alveolar epithelial cells challenged without or with cigarette smoke extract (CSE). TNF-α mRNA stability, and the decay of TNF-α mRNA, were determined by real-time quantitative RT-PCR. TNF-α protein levels were examined at the same time in these cells. To identify the molecular mechanism involved, a construct expressing the human beta-globin reporter mRNA containing the TNF-α 3’-untranslated region was generated to characterize the TTP targeted site within TNF-α mRNA. Results CSE induced TTP down-regulation in alveolar macrophages and alveolar epithelial cells. Reduced TTP expression resulted in significantly increased TNF-α mRNA stability. Importantly, increased TNF-α mRNA stability due to impaired TTP function resulted in significantly increased TNF-α levels in these cells. Forced TTP expression abrogated the increased TNF-α mRNA stability and expression induced by CSE. By using the globin reporter construct containing TNF-α mRNA 3’-untranslated region, the data indicate that TTP directly targets the adenine- and uridine-rich region (ARE) of TNF-α mRNA and negatively regulates TNF-α expression at the post-transcriptional level. Conclusion The data demonstrate that cigarette smoke exposure reduces TTP expression and impairs TTP function, resulting in significantly increased TNF-α mRNA stability and excessive TNF-α expression in alveolar macrophages and epithelial cells. The data suggest that TTP is a novel post-transcriptional regulator and limits excessive TNF-α expression and inflammatory response induced by

  19. MyD88 Signaling Regulates Steady-State Migration of Intestinal CD103+ Dendritic Cells Independently of TNF-α and the Gut Microbiota.

    Science.gov (United States)

    Hägerbrand, Karin; Westlund, Jessica; Yrlid, Ulf; Agace, William; Johansson-Lindbom, Bengt

    2015-09-15

    Intestinal homeostasis and induction of systemic tolerance to fed Ags (i.e., oral tolerance) rely on the steady-state migration of small intestinal lamina propria dendritic cells (DCs) into draining mesenteric lymph nodes (MLN). The majority of these migratory DCs express the α integrin chain CD103, and in this study we demonstrate that the steady-state mobilization of CD103(+) DCs into the MLN is in part governed by the IL-1R family/TLR signaling adaptor molecule MyD88. Similar to mice with complete MyD88 deficiency, specific deletion of MyD88 in DCs resulted in a 50-60% reduction in short-term accumulation of both CD103(+)CD11b(+) and CD103(+)CD11b(-) DCs in the MLN. DC migration was independent of caspase-1, which is responsible for the inflammasome-dependent proteolytic activation of IL-1 cytokine family members, and was not affected by treatment with broad-spectrum antibiotics. Consistent with the latter finding, the proportion and phenotypic composition of DCs were similar in mesenteric lymph from germ-free and conventionally housed mice. Although TNF-α was required for CD103(+) DC migration to the MLN after oral administration of the TLR7 agonist R848, it was not required for the steady-state migration of these cells. Similarly, TLR signaling through the adaptor molecule Toll/IL-1R domain-containing adapter inducing IFN-β and downstream production of type I IFN were not required for steady-state CD103(+) DC migration. Taken together, our results demonstrate that MyD88 signaling in DCs, independently of the microbiota and TNF-α, is required for optimal steady-state migration of small intestinal lamina propria CD103(+) DCs into the MLN. Copyright © 2015 by The American Association of Immunologists, Inc.

  20. Intracellular regulation of TNF activity in health and disease.

    Science.gov (United States)

    Varfolomeev, Eugene; Vucic, Domagoj

    2018-01-01

    Tumor Necrosis Factor alpha (TNFα, TNF) is a key mediator and regulator of mammalian immune responses in healthy organisms and in diseased conditions. TNF governs development of the immune system, cell survival signaling pathways, proliferation and regulates metabolic processes. Whereas TNF-induced NF-κB and MAP pro-survival kinase activities constitute its major biochemical functions, TNF can also stimulate cell death in certain pathological situations. TNF-induced signal transduction pathways are tightly regulated through ubiquitination and phosphorylation of molecules partaking in all TNF-dependent membrane-associated and intracellular protein signaling complexes. Deregulated TNF signaling in individuals carrying naturally occurring genetic mutations in proteins that mediate TNF signaling, or in corresponding genetically modified animal models, results in severe pathologies. In this review we will describe the current knowledge of TNF signaling and its relevance for human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Induction of TLR-2 and TLR-5 expression by Helicobacter pylori switches cagPAI-dependent signalling leading to the secretion of IL-8 and TNF-α.

    Directory of Open Access Journals (Sweden)

    Suneesh Kumar Pachathundikandi

    2011-05-01

    Full Text Available Helicobacter pylori is the causative agent for developing gastritis, gastric ulcer, and even gastric cancer. Virulent strains carry the cag pathogenicity island (cagPAI encoding a type-IV secretion system (T4SS for injecting the CagA protein. However, mechanisms of sensing this pathogen through Toll-like receptors (TLRs and downstream signalling pathways in the development of different pathologies are widely unclear. Here, we explored the involvement of TLR-2 and TLR-5 in THP-1 cells and HEK293 cell lines (stably transfected with TLR-2 or TLR-5 during infection with wild-type H. pylori and isogenic cagPAI mutants. H. pylori triggered enhanced TLR-2 and TLR-5 expression in THP-1, HEK293-TLR2 and HEK293-TLR5 cells, but not in the HEK293 control. In addition, IL-8 and TNF-α cytokine secretion in THP-1 cells was induced in a cagPAI-dependent manner. Furthermore, we show that HEK293 cells are not competent for the uptake of T4SS-delivered CagA, and are therefore ideally suited for studying TLR signalling in the absence of T4SS functions. HEK293 control cells, which do not induce TLR-2 and TLR-5 expression during infection, only secreted cytokines in small amounts, in agreement with T4SS functions being absent. In contrast, HEK293-TLR2 and HEK293-TLR5 cells were highly competent for inducing the secretion of IL-8 and TNF-α cytokines in a cagPAI-independent manner, suggesting that the expression of TLR-2 or TLR-5 has profoundly changed the capability to trigger pro-inflammatory signalling upon infection. Using phospho-specific antibodies and luciferase reporter assays, we further demonstrate that H. pylori induces IRAK-1 and IκB phosphorylation in a TLR-dependent manner, and this was required for activation of transcription factor NF-κB. Finally, NF-κB activation in HEK293-TLR2 and HEK293-TLR5 cells was confirmed by expressing p65-GFP which was translocated from the cytoplasm into the nucleus. These data indicate that H. pylori-induced expression

  2. Effect of TNF-α Inhibition on Bone Marrow-Derived Mesenchymal Stem Cells in Neurological Function Recovery after Spinal Cord Injury via the Wnt Signaling Pathway in a Rat Model.

    Science.gov (United States)

    Peng, Ren-Jun; Jiang, Bing; Ding, Xi-Ping; Huang, He; Liao, Yi-Wei; Peng, Gang; Cheng, Quan; Xi, Jian

    2017-01-01

    The present study aimed to examine the effect of tumor necrosis factor-α (TNF-α) inhibition on bone marrow-derived mesenchymal stem cells (BMSCs) in neurological function recovery after spinal cord injury (SCI) via the Wnt signaling pathway in a rat model. The rat model of SCI was established using Allen's method. Seventy-two adult male Sprague Dawley (SD) rats were randomly assigned into 4 groups (18 rats in each group): the sham control group, saline control group, BMSCs group (injection with BMSCs at the injured site) and BMSCs + TNF-α group (injection with BMSCs under TNF-α treatment at the injured site). Immunochemistry was performed to characterize the culture media after TNF-α-induced differentiation. qRT-PCR and Western blotting analyses were performed to detect the mRNA and protein expression of β-catenin, Wnt3a, GSK-3β and Axin. The Basso Beattie Bresnahan (BBB) locomotor score, neurological deficit score (NDS), and balance beam test (BBT) score were used to assess neurological functional recovery of SCI rats. In the BMSC group, numerous spherical cell clusters grew in suspension, and the cells were nestin-, NF200- and GFAP-positive. Compared with the sham control and BMSC groups, the β-catenin and Wnt3a mRNA and protein expression was increased, but the GSK-3β and Axin mRNA and protein expression was decreased in the BMSCs + TNF-α group. The SCI rats in the BMSCs + TNF-α group exhibited lower BBB scores, and higher NDSs and BBT scores compared to the BMSCs group. Our study provides evidence that TNF-α inhibition may weaken the ability of BMSCs in neurological functional recovery after SCI by activating the Wnt signaling pathway. © 2017 The Author(s). Published by S. Karger AG, Basel.

  3. CP-25, a Novel Anti-inflammatory and Immunomodulatory Drug, Inhibits the Functions of Activated Human B Cells through Regulating BAFF and TNF-alpha Signaling and Comparative Efficacy with Biological Agents

    Directory of Open Access Journals (Sweden)

    Feng Zhang

    2017-12-01

    Full Text Available Paeoniflorin-6′-O-benzene sulfonate (code: CP-25 was the chemistry structural modifications of Paeoniflorin (Pae. CP-25 inhibited B cells proliferation stimulated by B cell activating factor belonging to the TNF family (BAFF or Tumor necrosis factor alpha (TNF-alpha. CP-25, Rituximab and Etanercept reduced the percentage and numbers of CD19+ B cells, CD19+CD20+ B cells, CD19+CD27+ B cells and CD19+CD20+CD27+ B cells induced by BAFF or TNF-alpha. There was significant difference between CP-25 and Rituximab or CP-25 and Etanercept. CP-25 down-regulated the high expression of BAFFR, BCMA, and TACI stimulated by BAFF or TNF-alpha. The effects of Rituximab and Etanercept on BAFFR or BCMA were stronger than that of CP-25. CP-25, Rituximab and Etanercept down-regulated significantly the expression of TNFR1 and TNFR2 on B cell stimulated by BAFF or TNF-alpha. CP-25, Rituximab and Etanercept down-regulated the expression of MKK3, P-p38, P-p65, TRAF2, and p52 in B cells stimulated by BAFF and the expression of TRAF2 and P-p65 in B cells stimulated by TNF-alpha. These results suggest that CP-25 regulated moderately activated B cells function by regulating the classical and alternative NF-κB signaling pathway mediated by BAFF and TNF-alpha-TRAF2-NF-κB signaling pathway. This study suggests that CP-25 may be a promising anti-inflammatory immune and soft regulation drug.

  4. CP-25, a Novel Anti-inflammatory and Immunomodulatory Drug, Inhibits the Functions of Activated Human B Cells through Regulating BAFF and TNF-alpha Signaling and Comparative Efficacy with Biological Agents.

    Science.gov (United States)

    Zhang, Feng; Shu, Jin-Ling; Li, Ying; Wu, Yu-Jing; Zhang, Xian-Zheng; Han, Le; Tang, Xiao-Yu; Wang, Chen; Wang, Qing-Tong; Chen, Jing-Yu; Chang, Yan; Wu, Hua-Xun; Zhang, Ling-Ling; Wei, Wei

    2017-01-01

    Paeoniflorin-6'- O -benzene sulfonate (code: CP-25) was the chemistry structural modifications of Paeoniflorin (Pae). CP-25 inhibited B cells proliferation stimulated by B cell activating factor belonging to the TNF family (BAFF) or Tumor necrosis factor alpha (TNF-alpha). CP-25, Rituximab and Etanercept reduced the percentage and numbers of CD19 + B cells, CD19 + CD20 + B cells, CD19 + CD27 + B cells and CD19 + CD20 + CD27 + B cells induced by BAFF or TNF-alpha. There was significant difference between CP-25 and Rituximab or CP-25 and Etanercept. CP-25 down-regulated the high expression of BAFFR, BCMA, and TACI stimulated by BAFF or TNF-alpha. The effects of Rituximab and Etanercept on BAFFR or BCMA were stronger than that of CP-25. CP-25, Rituximab and Etanercept down-regulated significantly the expression of TNFR1 and TNFR2 on B cell stimulated by BAFF or TNF-alpha. CP-25, Rituximab and Etanercept down-regulated the expression of MKK3, P-p38, P-p65, TRAF2, and p52 in B cells stimulated by BAFF and the expression of TRAF2 and P-p65 in B cells stimulated by TNF-alpha. These results suggest that CP-25 regulated moderately activated B cells function by regulating the classical and alternative NF-κB signaling pathway mediated by BAFF and TNF-alpha-TRAF2-NF-κB signaling pathway. This study suggests that CP-25 may be a promising anti-inflammatory immune and soft regulation drug.

  5. Contributions of Noncanonical Smoothened Signaling During Embryonic Development

    OpenAIRE

    Pandit, Tanushree; Ogden, Stacey K.

    2017-01-01

    The Sonic Hedgehog (Shh) signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo), is a G protein-coupled receptor (GPCR) that has been demonstrated to signal through at least two effector routes. The first is a G protein–independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fa...

  6. Assessment of Anti-TNF-α Activities in Keratinocytes Expressing Inducible TNF- α: A Novel Tool for Anti-TNF-α Drug Screening

    Science.gov (United States)

    Udommethaporn, Sutthirat; Tencomnao, Tewin; McGowan, Eileen M.

    2016-01-01

    Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine important in normal and pathological biological processes. Newly synthesized pro-TNF-α is expressed on the plasma membrane and cleaved to release soluble TNF-α protein: both are biologically active. Secreted TNFsignals through TNF receptors and the membrane-bound TNF-α acts by cell contact-dependent signaling. Anti-TNF-α antibodies have been used effectively for treatment of chronic inflammation, however with adverse side effects. Thus, there is a need for new anti-TNF-α small molecule compounds. Anti-TNF-α activity assays involve treatment of keratinocytes with exogenous TNF-α before or after anti-TNF-α incubation. However, this model fails to address the dual signaling of TNF-α. Here we describe a Doxycycline (Dox)-inducible TNF-α (HaCaT-TNF-α) expression system in keratinocytes. Using this in-vitro model, we show cell inhibition and induced expression of pro-inflammatory cytokines and markers, including IL-1β, IL-6, IL-8, NF-κB1, and KRT-16, similar to cells treated with exogenous TNF-α. Sufficient secreted TNF-α produced also activated IL-1β and IL-8 expression in wt HaCaT cells. Importantly, stimulated expression of IL-1β and IL-8 in HaCaT-TNF-α were blocked by Quercetin, a flavanol shown to possess anti-TNF-α activities. This novel in vitro cell model provides an efficient tool to investigate the dual signaling of TNF-α. Importantly, this model provides an effective, fast, and simple screening for compounds with anti-TNF-α activities for chronic inflammatory disease therapies. PMID:27415000

  7. A novel CCR-2/TLR-2 triggered signaling in murine peritoneal macrophages intensifies bacterial (Staphylococcus aureus) killing by reactive oxygen species through TNF-R1.

    Science.gov (United States)

    Nandi, Ajeya; Bishayi, Biswadev

    2017-10-01

    Macrophages are remarkably versatile in their ability to recognize and respond to a wide range of stimuli by expressing a variety of surface and intracellular receptors and triggering multiple signal transduction pathways. The onset of microbial infection is primarily determined by the initial contacts made by the microbes with the host macrophages. Although there prevail a relationship between the chemokine receptor and Toll like receptors during disease, particularly TLR-2 and CCR-2 signaling interdependence on each other has not been yet investigated during acute staphylococcal infection. Thus, the present study was aimed to trace possible interaction between CCR-2 and TLR-2 in peritoneal macrophages during acute Staphylococcus aureus infection. We found that neutralization of CCR-2 attenuates TLR-2 expression and restricts S. aureus burden but TLR-2 neutralization augments CCR-2 expression in macrophages, along with compromised host-derived reactive oxygen species production. S. aureus infection to CCR-2 intact but TLR-2 neutralized macrophages triggered production of IL-1β, TNF-α, IL-6, IFN-γ, MCP-1 and expression of iNOS, TNFR-1 and GPx with concomitant decrease in IL-10 production. Further, study with NG-monomethyl-l-arginine (L-NMMA) [iNOS blocker] and buthionine sulfoximine (BSO) [GPx blocker] revealed that S. aureus infection enhanced TLR-2 expression in CCR-2 intact and TLR-2 neutralized macrophages possibly via iNOS and TNFR-1 up regulation and GPx down regulation. Overall, our data indicate that targeting CCR-2 with neutralizing antibody in the early phase of S. aureus infection could restrict excessive inflammation with less compromised bacterial killing. It certainly would be a therapeutic strategy in S. aureus induced inflammatory and infective diseases. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  8. Epidermal adrenergic signaling contributes to inflammation and pain sensitization in a rat model of complex regional pain syndrome.

    Science.gov (United States)

    Li, Wenwu; Shi, Xiaoyou; Wang, Liping; Guo, Tianzhi; Wei, Tzuping; Cheng, Kejun; Rice, Kenner C; Kingery, Wade S; Clark, J David

    2013-08-01

    In many patients, the sympathetic nervous system supports pain and other features of complex regional pain syndrome (CRPS). Accumulating evidence suggests that interleukin (IL)-6 also plays a role in CRPS, and that catecholamines stimulate production of IL-6 in several tissues. We hypothesized that norepinephrine acting through specific adrenergic receptors expressed on keratinocytes stimulates the production of IL-6 and leads to nociceptive sensitization in a rat tibial fracture/cast model of CRPS. Our approach involved catecholamine depletion using 6-hydroxydopamine or, alternatively, guanethidine, to explore sympathetic contributions. Both agents substantially reduced nociceptive sensitization and selectively reduced the production of IL-6 in skin. Antagonism of IL-6 signaling using TB-2-081 also reduced sensitization in this model. Experiments using a rat keratinocyte cell line demonstrated relatively high levels of β2-adrenergic receptor (β2-AR) expression. Stimulation of this receptor greatly enhanced IL-6 expression when compared to the expression of IL-1β, tumor necrosis factor (TNF)-α, or nerve growth factor. Stimulation of the cells also promoted phosphorylation of the mitogen-activated protein kinases P38, extracellular signal-regulated kinase, and c-Jun amino-terminal kinase. Based on these in vitro results, we returned to animal testing and observed that the selective β2-AR antagonist butoxamine reduced nociceptive sensitization in the CRPS model, and that local injection of the selective β2-AR agonist terbutaline resulted in mechanical allodynia and the production of IL-6 in the cells of the skin. No increases in IL-1β, TNF-α, or nerve growth factor levels were seen, however. These data suggest that in CRPS, norepinephrine released from sympathetic nerve terminals stimulates β2-ARs expressed on epidermal keratinocytes, resulting in local IL-6 production, and ultimately, pain sensitization. Published by Elsevier B.V.

  9. TNF and ROS Crosstalk in Inflammation

    DEFF Research Database (Denmark)

    Blaser, Heiko; Dostert, Catherine; Mak, Tak W

    2016-01-01

    Tumor necrosis factor (TNF) is tremendously important for mammalian immunity and cellular homeostasis. The role of TNF as a master regulator in balancing cell survival, apoptosis and necroptosis has been extensively studied in various cell types and tissues. Although these findings have revealed...... the role of TNF in the control of ROS/RNS signaling that influences innate immune cells under both physiological and inflammatory conditions. © 2015 Elsevier Ltd....

  10. IL-33/ST2 signalling contributes to carrageenin-induced innate inflammation and inflammatory pain: role of cytokines, endothelin-1 and prostaglandin E2.

    Science.gov (United States)

    Zarpelon, A C; Cunha, T M; Alves-Filho, J C; Pinto, L G; Ferreira, S H; McInnes, I B; Xu, D; Liew, F Y; Cunha, F Q; Verri, W A

    2013-05-01

    IL-33 signals through ST2 receptors and induces adaptive and innate inflammation. IL-33/ST2 is involved in adaptive inflammation-induced pain. Here, we have investigated the contribution of IL-33/ST2-triggered mechanisms to carrageenin-induced innate inflammation. Carrageenin- and IL-33-induced inflammatory responses were assessed in BALB/c- (WT) and ST2-deficient ((-/-) ) mice as follows: oedema (plethysmometer), myeloperoxidase activity (colorimetric assay), mechanical hyperalgesia (electronic version of von Frey filaments), cytokine levels (ELISA), PGE2 (RIA), mRNA expression (quantitative PCR), drug treatments targeting leukocyte recruitment (fucoidin), TNF-α (infliximab), CXCL1 (antibody to CXCL1), IL-1 (IL-1ra), endothelin ETA (clazosentan) and ETB (BQ788) receptors and COX (indomethacin). Carrageenin injection increased ST2 and IL-33 mRNA expression and IL-33 production in paw skin samples. Carrageenin-induced paw oedema, hyperalgesia and myeloperoxidase activity were reduced in ST2(-/-) compared with WT mice, effects mimicked by IL-33 injection in the paw. Furthermore, IL-33-induced hyperalgesia was reduced by fucoidin suggesting a role for recruited leukocytes in its hyperalgesic effect. IL-33-induced hyperalgesia in naïve mice was reduced by treatments targeting TNF, CXCL1, IL-1, endothelin receptors and COX while carrageenin-induced ST2-dependent TNF-α, CXCL1, IL-1β, IL-10 and PGE2 production and preproET-1 mRNA expression. Combining IL-33 and carrageenin at doses that were ineffective as single treatment induced significant hyperalgesia, oedema, myeloperoxidase activity and cytokine production in a ST2-dependent manner. IL-33/ST2 signalling triggers the production of inflammatory mediators contributing to carrageenin-induced inflammation. These data reinforces the importance of IL-33/ST2 signalling as a target in innate inflammation and inflammatory pain. © 2013 The Authors. British Journal of Pharmacology © 2013 The British Pharmacological

  11. Spatially restricted actin-regulatory signaling contributes to synapse morphology

    Science.gov (United States)

    Nicholson, Daniel A.; Cahill, Michael E.; Tulisiak, Christopher T.; Geinisman, Yuri; Penzes, Peter

    2012-01-01

    The actin cytoskeleton in dendritic spines is organized into microdomains, but how signaling molecules that regulate actin are spatially governed is incompletely understood. Here we examine how the localization of the RacGEF kalirin-7, a well-characterized regulator of actin in spines, varies as a function of postsynaptic density (PSD) area and spine volume. Using serial section electron microscopy (EM), we find that extrasynaptic, but not synaptic, expression of kalirin-7 varies directly with synapse size and spine volume. Moreover, we find that overall expression levels of kalirin-7 differ in spines bearing perforated and non-perforated synapses, due primarily to extrasynaptic pools of kalirin-7 expression in the former. Overall, our findings indicate that kalirin-7 is differentially compartmentalized in spines as a function of both synapse morphology and spine size. PMID:22458534

  12. DT-13 Ameliorates TNF-α-Induced Vascular Endothelial HyperpermeabilityviaNon-Muscle Myosin IIA and the Src/PI3K/Akt Signaling Pathway.

    Science.gov (United States)

    Zhang, Yuanyuan; Han, Yuwei; Zhao, Yazheng; Lv, Yanni; Hu, Yang; Tan, Yisha; Bi, Xueyuan; Yu, Boyang; Kou, Junping

    2017-01-01

    DT-13(25(R,S)-ruscogenin-1 -O- [β-d-glucopyranosyl-(1→2)][β-d-xylopyranosyl-(1→3)]-β-d-fucopyranoside) has been identified as an important factor in TNF-α-induced vascular inflammation. However, the effect of DT-13 on TNF-α-induced endothelial permeability and the potential molecular mechanisms remain unclear. Hence, this study was undertaken to elucidate the protective effect of DT-13 on TNF-α-induced endothelial permeability and the underlying mechanisms in vivo and in vitro . The in vivo results showed that DT-13 could ameliorate endothelial permeability in mustard oil-induced plasma leakage in the skin and modulate ZO-1 organization. In addition, the in vitro results showed that pretreatment with DT-13 could increase the transendothelial electrical resistance value and decrease the sodium fluorescein permeability coefficient. Moreover, DT-13 altered the mRNA and protein levels of ZO-1 as determined by real-time PCR, Western blotting, and immunofluorescence analyses. DT-13 treatment decreased the phosphorylations of Src, PI3K, and Akt in TNF-α-treated human umbilical vein endothelial cells (HUVECs). Further analyses with PP2 (10 µM, inhibitor of Src) indicated that DT-13 modulated endothelial permeability in TNF-α-induced HUVECs in an Src-dependent manner. LY294002 (10 µM, PI3K inhibitor) also had the same effect on DT-13 but did not affect phosphorylation of Src. Following decreased expression of non-muscle myosin IIA (NMIIA), the effect of DT-13 on the phosphorylations of Src, PI3K, and Akt was abolished. This study provides pharmacological evidence showing that DT-13 significantly ameliorated the TNF-α-induced vascular endothelial hyperpermeability through modulation of the Src/PI3K/Akt pathway and NMIIA, which play an important role in this process.

  13. Fluid shear stress suppresses TNF-α-induced apoptosis in MC3T3-E1 cells: Involvement of ERK5-AKT-FoxO3a-Bim/FasL signaling pathways

    International Nuclear Information System (INIS)

    Bin, Geng; Bo, Zhang; Jing, Wang; Jin, Jiang; Xiaoyi, Tan; Cong, Chen; Liping, An; Jinglin, Ma; Cuifang, Wang; Yonggang, Chen; Yayi, Xia

    2016-01-01

    TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed the FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis. - Highlights: • Fluid shear stress inhibits osteoblast apoptosis induced by TNF-α. • Inhibition of ERK5 activity by transfection of ERK5 siRNA blocks FSS-mediated anti-apoptotic effect in osteoblast. • Activated ERK5-AKT-FoxO3a-Bim/FasL signaling pathways by FSS is required to protect osteoblast from apoptosis.

  14. Fluid shear stress suppresses TNF-α-induced apoptosis in MC3T3-E1 cells: Involvement of ERK5-AKT-FoxO3a-Bim/FasL signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Bin, Geng; Bo, Zhang; Jing, Wang; Jin, Jiang; Xiaoyi, Tan; Cong, Chen; Liping, An; Jinglin, Ma; Cuifang, Wang; Yonggang, Chen [The Second Hospital of Lanzhou University, #82 Cuiyingmen, Lanzhou, 730000 Gansu (China); Orthopaedics Key Laboratory of Gansu Province, Lanzhou, 730000 Gansu (China); Yayi, Xia, E-mail: xiayayildey@163.com [The Second Hospital of Lanzhou University, #82 Cuiyingmen, Lanzhou, 730000 Gansu (China); Orthopaedics Key Laboratory of Gansu Province, Lanzhou, 730000 Gansu (China)

    2016-05-01

    TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed the FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis. - Highlights: • Fluid shear stress inhibits osteoblast apoptosis induced by TNF-α. • Inhibition of ERK5 activity by transfection of ERK5 siRNA blocks FSS-mediated anti-apoptotic effect in osteoblast. • Activated ERK5-AKT-FoxO3a-Bim/FasL signaling pathways by FSS is required to protect osteoblast from apoptosis.

  15. TNF and TNF Receptor Superfamily Members in HIV infection: New Cellular Targets for Therapy?

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2013-01-01

    Full Text Available Tumor necrosis factor (TNF and TNF receptors (TNFR superfamily members are engaged in diverse cellular phenomena such as cellular proliferation, morphogenesis, apoptosis, inflammation, and immune regulation. Their role in regulating viral infections has been well documented. Viruses have evolved with numerous strategies to interfere with TNF-mediated signaling indicating the importance of TNF and TNFR superfamily in viral pathogenesis. Recent research reports suggest that TNF and TNFRs play an important role in the pathogenesis of HIV. TNFR signaling modulates HIV replication and HIV proteins interfere with TNF/TNFR pathways. Since immune activation and inflammation are the hallmark of HIV infection, the use of TNF inhibitors can have significant impact on HIV disease progression. In this review, we will describe how HIV infection is modulated by signaling mediated through members of TNF and TNFR superfamily and in turn how these latter could be targeted by HIV proteins. Finally, we will discuss the emerging therapeutics options based on modulation of TNF activity that could ultimately lead to the cure of HIV-infected patients.

  16. Glossogyne tenuifolia Extract Inhibits TNF-α-Induced Expression of Adhesion Molecules in Human Umbilical Vein Endothelial Cells via Blocking the NF-kB Signaling Pathway.

    Science.gov (United States)

    Hsuan, Chin-Feng; Hsu, Hsia-Fen; Tseng, Wei-Kung; Lee, Thung-Lip; Wei, Yu-Feng; Hsu, Kwan-Lih; Wu, Chau-Chung; Houng, Jer-Yiing

    2015-09-17

    Chronic inflammation plays a pivotal role in the development of atherosclerosis, where the pro-inflammatory cytokine-induced expression of endothelial adhesion molecules and the recruitment of monocytes are the crucial events leading to its pathogenesis. Glossogyne tenuifolia ethanol extract (GTE) is shown to have potent anti-inflammatory and antioxidant activities. We evaluated the effects of GTE and its major components, luteolin (lut), luteolin-7-glucoside (lut-7-g), and oleanolic acid (OA) on TNF-α-induced expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). The results demonstrated that GTE, lut, and lut-7-g attenuated the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-activated HUVECs, and inhibited the adhesion of monocytes to TNF-α-activated HUVECs. The TNF-α-induced mRNA expression of ICAM-1 and VCAM-1 was also suppressed, revealing their inhibitory effects at the transcriptional level. Furthermore, GTE, lut, and lut-7-g blocked the TNF-α-induced degradation of nuclear factor-kB inhibitor (IkB), an indicator of the activation of nuclear factor-kB (NF-kB). In summary, GTE and its bioactive components were effective in preventing the adhesion of monocytes to cytokine-activated endothelium by the inhibition of expression of adhesion molecules, which in turn is mediated through blocking the activation and nuclear translocation of NF-kB. The current results reveal the therapeutic potential of GTE in atherosclerosis.

  17. Physiological Role of TNF in MucosalImmunology: Regulation of Macrophage/Dendritic Cell Function

    DEFF Research Database (Denmark)

    Rivollier, Aymeric Marie Christian; Marsal, J.; Agace, William Winston

    2015-01-01

    to the pathogenesis of inflammatory bowel disease. In this review, we discuss the role of tumor necrosis factor-α (TNF) in regulating multiple aspects of intestinal Mϕ and DC physiology, including their differentiation, migration, maturation, survival and effector functions. In inflammatory bowel disease, TNF...... signaling has been implicated in reprogramming monocyte differentiation from the anti-inflammatory Mϕ lineage towards the pro-inflammatory mononuclear phagocyte lineage.These cells become a major source of TNF and, thus,may contribute to the chronic inflammatory process. Finally,we highlight some...... of the important gaps in our current knowledge regarding the role of TNF in Mϕ and DCphysiology and suggest important directions for future research in this field....

  18. Dysphagia Screening: Contributions of Cervical Auscultation Signals and Modern Signal-Processing Techniques.

    Science.gov (United States)

    Dudik, Joshua M; Coyle, James L; Sejdić, Ervin

    2015-08-01

    Cervical auscultation is the recording of sounds and vibrations caused by the human body from the throat during swallowing. While traditionally done by a trained clinician with a stethoscope, much work has been put towards developing more sensitive and clinically useful methods to characterize the data obtained with this technique. The eventual goal of the field is to improve the effectiveness of screening algorithms designed to predict the risk that swallowing disorders pose to individual patients' health and safety. This paper provides an overview of these signal processing techniques and summarizes recent advances made with digital transducers in hopes of organizing the highly varied research on cervical auscultation. It investigates where on the body these transducers are placed in order to record a signal as well as the collection of analog and digital filtering techniques used to further improve the signal quality. It also presents the wide array of methods and features used to characterize these signals, ranging from simply counting the number of swallows that occur over a period of time to calculating various descriptive features in the time, frequency, and phase space domains. Finally, this paper presents the algorithms that have been used to classify this data into 'normal' and 'abnormal' categories. Both linear as well as non-linear techniques are presented in this regard.

  19. Targeting TNF and TNF Receptor Pathway in HIV-1 Infection: from Immune Activation to Viral Reservoirs.

    Science.gov (United States)

    Pasquereau, Sébastien; Kumar, Amit; Herbein, Georges

    2017-03-30

    Several cellular functions such as apoptosis, cellular proliferation, inflammation, and immune regulation involve the tumor necrosis factor-α (TNF)/TNF receptor (TNFR) pathway. Human immunodeficiency virus 1 (HIV-1) interacts with the TNF/TNFR pathway. The activation of the TNF/TNFR pathway impacts HIV-1 replication, and the TNF/TNFR pathway is the target of HIV-1 proteins. A hallmark of HIV-1 infection is immune activation and inflammation with increased levels of TNF in the plasma and the tissues. Therefore, the control of the TNF/TNFR pathway by new therapeutic approaches could participate in the control of immune activation and impact both viral replication and viral persistence. In this review, we will describe the intricate interplay between HIV-1 proteins and TNF/TNFR signaling and how TNF/TNFR activation modulates HIV-1 replication and discuss new therapeutic approaches, especially anti-TNF therapy, that could control this pathway and ultimately favor the clearance of infected cells to cure HIV-infected patients.

  20. Soluble Calreticulin Induces Tumor Necrosis Factor-α (TNF-α and Interleukin (IL-6 Production by Macrophages through Mitogen-Activated Protein Kinase (MAPK and NFκB Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Cui-Cui Duo

    2014-02-01

    Full Text Available We have recently reported that soluble calreticulin (CRT accumulates in the sera of patients with rheumatoid arthritis or systemic lupus erythematosus. Moreover, following self-oligomerization, soluble recombinant CRT (rCRT polypeptides exhibit potent immunostimulatory activities including macrophage activation in vitro and antibody induction in vivo. This study was designed to further investigate the underlying molecular mechanisms for soluble CRT-induced macrophage activation. Treatment of murine macrophages with oligomerized rCRT (OrCRT led to (i TNF-α and IL-6 transcription and protein expression without affecting intracellular mRNA stability; and (ii IκBα degradation, NFκB phosphorylation and sustained MAPK phosphorylation in cells. Inhibition of IKK and JNK in macrophages substantially abrogated production of TNF-α and IL-6 induced by OrCRT, while ERK suppression only reduced IL-6 expression in parallel experiments. In vitro, fucoidan, a scavenger receptor A (SRA-specific ligand, significantly reduced the uptake of FITC-labeled OrCRT by macrophages and subsequent MAPK and NFκB activation, thereby suggesting SRA as one of the potential cell surface receptors for soluble CRT. Together, these data indicate that soluble CRT in oligomerized form could play a pathogenic role in autoimmune diseases through induction of pro-inflammatory cytokines (e.g., TNF-α and IL-6 by macrophages via MAPK-NFκB signaling pathway.

  1. KLF5 overexpression attenuates cardiomyocyte inflammation induced by oxygen-glucose deprivation/reperfusion through the PPARγ/PGC-1α/TNFsignaling pathway.

    Science.gov (United States)

    Li, Yang; Li, Jian; Hou, Zhiwen; Yu, Yang; Yu, Bo

    2016-12-01

    The primary physiological function of Krüppel-like zinc-finger transcription factor (KLF5) is the regulation of cardiovascular remodeling. Vascular remodeling is closely related to the amelioration of various ischemic diseases. However, the underlying correlation of KLF5 and ischemia is not clear. In this study, we aim to investigate the role of KLF5 in myocardial ischemia reperfusion (IR) injury and the potential mechanisms involved. Cultured H9C2 cells were subjected to oxygen-glucose deprivation/reperfusion (OGD/Rep) to mimic myocardial IR injury in vivo. Expressions of KLF5 and PPARγ were distinctly inhibited, and PGC-1α expression was activated at 24h after myocardial OGD/Rep injury. After myocardial OGD/Rep injury, we found that KLF5 overexpression down-regulated levels of TNF-α, IL-1β, IL-6 and IL-8. Through the analysis of lactate dehydrogenase (LDH) release, we demonstrate that KLF5 overexpression reduced the release of OGD/Rep-induced LDH. KLF5 overexpression significantly enhanced cell activity and decreased cell apoptosis during OGD/Rep injury. Compared with the OGD/Rep group, cells overexpressing KLF5 showed anti-apoptotic effects, such as decreased expression of Bax and cleaved caspase-3 as well as increased Bcl-2 expression. KLF5 overexpression activated PPARγ, a protein involved in OGD/Rep injury, and increased levels of PGC-1α, while TNF-α expression was remarkably inhibited. In addition, GW9662, a PPARγ receptor antagonist, reversed the expression of PPARγ/PGC-1α/TNF-α and cell activity induced by KLF5 overexpression. The effects of KLF5 overexpression on PPARγ/PGC-1α/TNF-α and cell activity were abolished by co-treatment with GW9662. Taken together, these results suggest that KLF5 can efficiently alleviate OGD/Rep-induced myocardial injury, perhaps through regulation of the PPARγ/PGC-1α/TNF-α pathway. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. RAGE-dependent signaling in microglia contributes to neuroinflammation, Aβ accumulation, and impaired learning/memory in a mouse model of Alzheimer’s disease

    Science.gov (United States)

    Fang, Fang; Lue, Lih-Fen; Yan, Shiqiang; Xu, Hongwei; Luddy, John S.; Chen, Doris; Walker, Douglas G.; Stern, David M.; Yan, Shifang; Schmidt, Ann Marie; Chen, John X.; Yan, Shirley ShiDu

    2010-01-01

    Microglia are critical for amyloid-β peptide (Aβ)-mediated neuronal perturbation relevant to Alzheimer’s disease (AD) pathogenesis. We demonstrate that overexpression of receptor for advanced glycation end products (RAGE) in imbroglio exaggerates neuroinflammation, as evidenced by increased proinflammatory mediator production, Aβ accumulation, impaired learning/memory, and neurotoxicity in an Aβ-rich environment. Transgenic (Tg) mice expressing human mutant APP (mAPP) in neurons and RAGE in microglia displayed enhanced IL-1β and TNF-α production, increased infiltration of microglia and astrocytes, accumulation of Aβ, reduced acetylcholine esterase (AChE) activity, and accelerated deterioration of spatial learning/memory. Notably, introduction of a signal transduction-defective mutant RAGE (DN-RAGE) to microglia attenuates deterioration induced by Aβ. These findings indicate that RAGE signaling in microglia contributes to the pathogenesis of an inflammatory response that ultimately impairs neuronal function and directly affects amyloid accumulation. We conclude that blockade of microglial RAGE may have a beneficial effect on Aβ-mediated neuronal perturbation relevant to AD pathogenesis.—Fang, F., Lue, L.-F., Yan, S., Xu, H., Luddy, J. S., Chen, D., Walker, D. G., Stern, D. M., Yan, S., Schmidt, A. M., Chen, J. X., Yan, S. S. RAGE-dependent signaling in microglia contributes to neuroinflammation, Aβ accumulation, and impaired learning/memory in a mouse model of Alzheimer’s disease. PMID:19906677

  3. Involvement of c-Jun N-Terminal Kinase in TNF-α-Driven Remodeling.

    Science.gov (United States)

    Eurlings, Irene M J; Reynaert, Niki L; van de Wetering, Cheryl; Aesif, Scott W; Mercken, Evi M; de Cabo, Rafael; van der Velden, Jos L; Janssen-Heininger, Yvonne M; Wouters, Emiel F M; Dentener, Mieke A

    2017-03-01

    Lung tissue remodeling in chronic obstructive pulmonary disease (COPD) is characterized by airway wall thickening and/or emphysema. Although the bronchial and alveolar compartments are functionally independent entities, we recently showed comparable alterations in matrix composition comprised of decreased elastin content and increased collagen and hyaluronan contents of alveolar and small airway walls. Out of several animal models tested, surfactant protein C (SPC)-TNF-α mice showed remodeling in alveolar and airway walls similar to what we observed in patients with COPD. Epithelial cells are able to undergo a phenotypic shift, gaining mesenchymal properties, a process in which c-Jun N-terminal kinase (JNK) signaling is involved. Therefore, we hypothesized that TNF-α induces JNK-dependent epithelial plasticity, which contributes to lung matrix remodeling. To this end, the ability of TNF-α to induce a phenotypic shift was assessed in A549, BEAS2B, and primary bronchial epithelial cells, and phenotypic markers were studied in SPC-TNF-α mice. Phenotypic markers of mesenchymal cells were elevated both in vitro and in vivo, as shown by the expression of vimentin, plasminogen activator inhibitor-1, collagen, and matrix metalloproteinases. Concurrently, the expression of the epithelial markers, E-cadherin and keratin 7 and 18, was attenuated. A pharmacological inhibitor of JNK attenuated this phenotypic shift in vitro, demonstrating involvement of JNK signaling in this process. Interestingly, activation of JNK signaling was also clearly present in lungs of SPC-TNF-α mice and patients with COPD. Together, these data show a role for TNF-α in the induction of a phenotypic shift in vitro, resulting in increased collagen production and the expression of elastin-degrading matrix metalloproteinases, and provide evidence for involvement of the TNF-α-JNK axis in extracellular matrix remodeling.

  4. TNF-α inhibits SATB2 expression and osteoblast differentiation through NF-κB and MAPK pathways.

    Science.gov (United States)

    Zuo, Chijian; Zhao, Xiaoying; Shi, Yu; Wu, Wen; Zhang, Ning; Xu, Jiake; Wang, Chuandong; Hu, Guoli; Zhang, Xiaoling

    2018-01-12

    Although the mechanisms of Tumor necrosis factor alpha (TNF-α) on facilitating osteoclast differentiation and bone resorption is well known, the mechanisms behind the suppression of the osteoblast differentiation from mesenchymal stem cells (MSCs) are still poorly understood. In this study, we observed a negative correlation between TNF-α levels and the expression of special AT-rich sequence-binding protein 2 (SATB2), a critical osteoblastogenesis transcription factor, in ovariectomy (OVX)-induced bone loss and IL-1-induced arthritis animal model. We found that TNF-α treatment inhibited mesenchymal cell line C2C12 osteoblast differentiation and sharply decreased BMP2-induced SATB2 expression. Upon TNF-α treatment, the activity of smad1/5/8 was inhibited, by contrast, extracellular signal-regulated kinase-1/2 (ERK1/2) and P38 was increased in C2C12 cells, the inhibitor of ERK1/2 (U0126) was found to abrogate the TNF-α inhibition of SATB2 expression. Furthermore, the NF-κB signaling pathway in C2C12 cells was significantly activated by the treatment of TNF-α, and TNF-α induced NF-κB directly binds to SATB2 promoter to suppress its expression. These results suggest that TNF-α suppresses SATB2 expression through activating NF-κB and MAPK signaling and depressing smad1/5/8 signaling, which contributes to the inhibition of osteoblast differentiation and might be potential therapeutic targets for inflammation-induced bone loss.

  5. Impaired CD40L signaling is a cause of defective IL-12 and TNF-alpha production in Sézary syndrome: circumvention by hexameric soluble CD40L.

    Science.gov (United States)

    French, Lars E; Huard, Bertrand; Wysocka, Maria; Shane, Ryan; Contassot, Emmanuel; Arrighi, Jean-François; Piguet, Vincent; Calderara, Silvio; Rook, Alain H

    2005-01-01

    Sézary syndrome (SzS) is an advanced form of cutaneous T-cell lymphoma characterized by peripheral blood involvement, impaired cell-mediated immunity, and T-helper 1 (TH1) cytokine production. To understand the mechanism of these defects, we studied the expression and function of CD40L in peripheral blood mononuclear cells (PBMCs) of patients with SzS. We found that PBMCs of patients with SzS have a defect in interleukin-12 (IL-12) and tumor necrosis factor-alpha (TNF-alpha) production upon anti-CD3 stimulation and that tumor CD4+ T lymphocytes have a specific defect in CD40L induction after anti-CD3 ligation in vitro. This defect may explain the poor IL-12 production, because IL-12 production by anti-CD3-stimulated PBMCs was dependent on CD40L in healthy donors. The observed defect in tumor cell CD40L expression appears to be due to inappropriate T-cell signaling upon CD3 ligation, because expression of other T-cell activation antigens such as CD25, and to a lesser extent CD69, are also impaired on tumor cells. Importantly however, the inability of SzS PBMCs to appropriately produce IL-12 and TNF-alpha could be restored by recombinant hexameric CD40L. Taken together, our results demonstrate that impaired IL-12 and TNF-alpha production in SzS is associated with defective CD4+ T lymphocyte CD40L induction and indicate that CD40L may have therapeutic potential in SzS.

  6. Analytical ultracentrifugation with fluorescence detection system reveals differences in complex formation between recombinant human TNF and different biological TNF antagonists in various environments.

    Science.gov (United States)

    Krayukhina, Elena; Noda, Masanori; Ishii, Kentaro; Maruno, Takahiro; Wakabayashi, Hirotsugu; Tada, Minoru; Suzuki, Takuo; Ishii-Watabe, Akiko; Kato, Masahiko; Uchiyama, Susumu

    A number of studies have attempted to elucidate the binding mechanism between tumor necrosis factor (TNF) and clinically relevant antagonists. None of these studies, however, have been conducted as close as possible to physiologic conditions, and so the relationship between the size distribution of TNF-antagonist complexes and the antagonists' biological activity or adverse effects remains elusive. Here, we characterized the binding stoichiometry and sizes of soluble TNF-antagonist complexes for adalimumab, infliximab, and etanercept that were formed in human serum and in phosphate-buffered saline (PBS). Fluorescence-detected sedimentation velocity analytical ultracentrifugation analyses revealed that adalimumab and infliximab formed a range of complexes with TNF, with the major complexes consisting of 3 molcules of the respective antagonist and one or 2 molcules of TNF. Considerably greater amounts of high-molecular-weight complexes were detected for infliximab in human serum. The emergence of peaks with higher sedimentation coefficients than the adalimumab monomer as a function of added human serum albumin (HSA) concentration in PBS suggested weak reversible interactions between HSA and immunoglobulins. Etanerept exclusively formed 1:1 complexes with TNF in PBS, and a small amount of complexes with higher stoichiometry was detected in human serum. Consistent with these biophysical characterizations, a reporter assay showed that adalimumab and infliximab, but not etanercept, exerted FcγRIIa- and FcγRIIIa-mediated cell signaling in the presence of TNF and that infliximab exhibited higher potency than adalimumab. This study shows that assessing distribution profiles in serum will contribute to a more comprehensive understanding of the in vivo behavior of therapeutic proteins.

  7. SDF-1 induces TNF-mediated apoptosis in cardiac myocytes.

    Science.gov (United States)

    Jarrah, Andrew A; Schwarskopf, Martina; Wang, Edward R; LaRocca, Thomas; Dhume, Ashwini; Zhang, Shihong; Hadri, Lahouria; Hajjar, Roger J; Schecter, Alison D; Tarzami, Sima T

    2018-01-01

    Chemokines are small secreted proteins with chemoattractant properties that play a key role in inflammation. One such chemokine, Stromal cell-derived factor-1 (SDF-1) also known as CXCL12, and its receptor, CXCR4, are expressed and functional in cardiac myocytes. SDF-1 both stimulates and enhances the cellular signal which attracts potentially beneficial stem cells for tissue repair within the ischemic heart. Paradoxically however, this chemokine is known to act in concert with the inflammatory cytokines of the innate immune response which contributes to cellular injury through the recruitment of inflammatory cells during ischemia. In the present study, we have demonstrated that SDF-1 has dose dependent effects on freshly isolated cardiomyocytes. Using Tunnel and caspase 3-activation assays, we have demonstrated that the treatment of isolated adult rat cardiac myocyte with SDF-1 at higher concentrations (pathological concentrations) induced apoptosis. Furthermore, ELISA data demonstrated that the treatment of isolated adult rat cardiac myocyte with SDF-1 at higher concentrations upregulated TNF-α protein expression which directly correlated with subsequent apoptosis. There was a significant reduction in SDF-1 mediated apoptosis when TNF-α expression was neutralized which suggests that SDF-1 mediated apoptosis is TNF-α-dependent. The fact that certain stimuli are capable of driving cardiomyocytes into apoptosis indicates that these cells are susceptible to clinically relevant apoptotic triggers. Our findings suggest that the elevated SDF-1 levels seen in a variety of clinical conditions, including ischemic myocardial infarction, may either directly or indirectly contribute to cardiac cell death via a TNF-α mediated pathway. This highlights the importance of this receptor/ligand in regulating the cardiomyocyte response to stress conditions.

  8. Necroptosis Mediates TNF-Induced Toxicity of Hippocampal Neurons

    Directory of Open Access Journals (Sweden)

    Shan Liu

    2014-01-01

    Full Text Available Tumor necrosis factor-α (TNF-α is a critical proinflammatory cytokine regulating neuroinflammation. Elevated levels of TNF-α have been associated with various neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. However, the signaling events that lead to TNF-α-initiated neurotoxicity are still unclear. Here, we report that RIP3-mediated necroptosis, a form of regulated necrosis, is activated in the mouse hippocampus after intracerebroventricular injection of TNF-α. RIP3 deficiency attenuates TNF-α-initiated loss of hippocampal neurons. Furthermore, we characterized the molecular mechanism of TNF-α-induced neurotoxicity in HT-22 hippocampal neuronal cells. HT-22 cells are sensitive to TNF-α only upon caspase blockage and subsequently undergo necrosis. The cell death is suppressed by knockdown of CYLD or RIP1 or RIP3 or MLKL, suggesting that this necrosis is necroptosis and mediated by CYLD-RIP1-RIP3-MLKL signaling pathway. TNF-α-induced necroptosis of HT-22 cells is largely independent of both ROS accumulation and calcium influx although these events have been shown to be critical for necroptosis in certain cell lines. Taken together, these data not only provide the first in vivo evidence for a role of RIP3 in TNF-α-induced toxicity of hippocampal neurons, but also demonstrate that TNF-α promotes CYLD-RIP1-RIP3-MLKL-mediated necroptosis of hippocampal neurons largely bypassing ROS accumulation and calcium influx.

  9. Radiation targeted TNF gene therapy in TNF-resistant prostate cancer

    International Nuclear Information System (INIS)

    Chung, Theodore D.K.; Mauceri, Helena J.; Hallahan, Dennis E.; Yu, Jenny; Yajnik, Santosh; Weichselbaum, Ralph R.

    1997-01-01

    with Ad.Egr-TNF and 40 Gy lead to progressive reduction of the mean tumor volume to 17% of original at day 59. In the 40 Gy alone group, tumors initially regressed to 73% of the original volume at day 28, but subsequently regrew to 2.3 times the original volume by day 59. Ad.Egr-TNF alone had little or no effect on tumor growth. Conclusions: Although TNF has limited cytotoxic or radiosensitizing activity in human prostate cancer PC-3 cell line in vitro, radiation targeted gene therapy with Ad.Egr-TNF increases tumor control in xenografts. These results suggest indirect mechanisms may contribute to tumor cell killing in vivo. Preliminary histopathologic evaluation confirm the presence of TNF/radiation-induced vascular obliteration

  10. Dual role of the p75 tumor necrosis factor (TNF) receptor in TNF cytotoxicity

    DEFF Research Database (Denmark)

    Bigda, J; Beletsky, I; Brakebusch, C

    1994-01-01

    Whereas there is ample evidence for involvement of the p55 tumor necrosis factor (TNF) receptor (p55-R) in the cytocidal effect of TNF, the role of the p75 TNF receptor (p75-R) in this effect is a matter of debate. In this study, we probed the function of p75-R in cells sensitive...... to the cytotoxicity of TNF using a wide panel of antibodies (Abs) against the receptor's extracellular domain. Two distinct Ab effects were observed. The Abs triggered signaling for cytotoxicity. This effect: (a) was correlated with the extent of p75-R expression by the cells; (b) was dependent on receptor cross...... against p55-R. Moreover, it seemed to reverse induced desensitization to the cytocidal effect of anti p55-R Abs, suggesting that it involves mechanisms different from those of the signaling by the p55 TNF-R. In addition, the Abs affected the response to TNF in a way that does not involve the signaling...

  11. TNF biology, pathogenic mechanisms and emerging therapeutic strategies

    Science.gov (United States)

    Kalliolias, George D.; Ivashkiv, Lionel B.

    2016-01-01

    TNF is a pleiotropic cytokine with important functions in homeostasis and disease pathogenesis. Recent discoveries have provided insights into TNF biology that introduce new concepts for the development of therapeutics for TNF-mediated diseases. The model of TNF receptor signalling has been extended to include linear ubiquitination and the formation of distinct signalling complexes that are linked with different functional outcomes, such as inflammation, apoptosis and necroptosis. Our understanding of TNF-induced gene expression has been enriched by the discovery of epigenetic mechanisms and concepts related to cellular priming, tolerization and induction of ‘short-term transcriptional memory’. Identification of distinct homeostatic or pathogenic TNF-induced signalling pathways has introduced the concept of selectively inhibiting the deleterious effects of TNF while preserving its homeostatic bioactivities for therapeutic purposes. In this Review, we present molecular mechanisms underlying the roles of TNF in homeostasis and inflammatory disease pathogenesis, and discuss novel strategies to advance therapeutic paradigms for the treatment of TNF-mediated diseases. PMID:26656660

  12. Toll-like receptor 4 signaling in neurons of trigeminal ganglion contributes to nociception induced by acute pulpitis in rats.

    Science.gov (United States)

    Lin, Jia-Ji; Du, Yi; Cai, Wen-Ke; Kuang, Rong; Chang, Ting; Zhang, Zhuo; Yang, Yong-Xiang; Sun, Chao; Li, Zhu-Yi; Kuang, Fang

    2015-07-30

    Pain caused by acute pulpitis (AP) is a common symptom in clinical settings. However, its underlying mechanisms have largely remained unknown. Using AP model, we demonstrated that dental injury caused severe pulp inflammation with up-regulated serum IL-1β. Assessment from head-withdrawal reflex thresholds (HWTs) and open-field test demonstrated nociceptive response at 1 day post injury. A consistent up-regulation of Toll-like receptor 4 (TLR4) in the trigeminal ganglion (TG) ipsilateral to the injured pulp was found; and downstream signaling components of TLR4, including MyD88, TRIF and NF-κB, and cytokines such as TNF-α and IL-1β, were also increased. Retrograde labeling indicated that most TLR4 positve neuron in the TG innnervated the pulp and TLR4 immunoreactivity was mainly in the medium and small neurons. Double labeling showed that the TLR4 expressing neurons in the ipsilateral TG were TRPV1 and CGRP positive, but IB4 negative. Furthermore, blocking TLR4 by eritoran (TLR4 antagonist) in TGs of the AP model significantly down-regulated MyD88, TRIF, NF-κB, TNF-α and IL-1β production and behavior of nociceptive response. Our findings suggest that TLR4 signaling in TG cells, particularly the peptidergic TRPV1 neurons, plays a key role in AP-induced nociception, and indicate that TLR4 signaling could be a potential therapeutic target for orofacial pain.

  13. Diet-induced obesity elevates colonic TNF-alpha in mice and is accompanied by an activation of Wnt signaling: a mechanism for obesity-associated colorectal cancer

    Science.gov (United States)

    Inflammation associated with obesity may play a role in colorectal carcinogenesis, but the underlying mechanism remains unclear. This study investigated whether the Wnt pathway, an intracellular signaling cascade that plays a critical role in colorectal carcinogenesis, is activated by obesity-induce...

  14. Angiotensin II–dependent TGF-β signaling contributes to Loeys-Dietz syndrome vascular pathogenesis

    Science.gov (United States)

    Gallo, Elena M.; Loch, David C.; Habashi, Jennifer P.; Calderon, Juan F.; Chen, Yichun; Bedja, Djahida; van Erp, Christel; Gerber, Elizabeth E.; Parker, Sarah J.; Sauls, Kimberly; Judge, Daniel P.; Cooke, Sara K.; Lindsay, Mark E.; Rouf, Rosanne; Myers, Loretha; ap Rhys, Colette M.; Kent, Kathleen C.; Norris, Russell A.; Huso, David L.; Dietz, Harry C.

    2013-01-01

    Loeys-Dietz syndrome (LDS) is a connective tissue disorder that is characterized by a high risk for aneurysm and dissection throughout the arterial tree and phenotypically resembles Marfan syndrome. LDS is caused by heterozygous missense mutations in either TGF-β receptor gene (TGFBR1 or TGFBR2), which are predicted to result in diminished TGF-β signaling; however, aortic surgical samples from patients show evidence of paradoxically increased TGF-β signaling. We generated 2 knockin mouse strains with LDS mutations in either Tgfbr1 or Tgfbr2 and a transgenic mouse overexpressing mutant Tgfbr2. Knockin and transgenic mice, but not haploinsufficient animals, recapitulated the LDS phenotype. While heterozygous mutant cells had diminished signaling in response to exogenous TGF-β in vitro, they maintained normal levels of Smad2 phosphorylation under steady-state culture conditions, suggesting a chronic compensation. Analysis of TGF-β signaling in the aortic wall in vivo revealed progressive upregulation of Smad2 phosphorylation and TGF-β target gene output, which paralleled worsening of aneurysm pathology and coincided with upregulation of TGF-β1 ligand expression. Importantly, suppression of Smad2 phosphorylation and TGF-β1 expression correlated with the therapeutic efficacy of the angiotensin II type 1 receptor antagonist losartan. Together, these data suggest that increased TGF-β signaling contributes to postnatal aneurysm progression in LDS. PMID:24355923

  15. Altered TGF-β endocytic trafficking contributes to the increased signaling in Marfan syndrome.

    Science.gov (United States)

    Siegert, Anna-Maria; Serra-Peinado, Carla; Gutiérrez-Martínez, Enric; Rodríguez-Pascual, Fernando; Fabregat, Isabel; Egea, Gustavo

    2018-02-01

    The main cardiovascular alteration in Marfan syndrome (MFS) is the formation of aortic aneurysms in which augmented TGF-β signaling is reported. However, the primary role of TGF-β signaling as a molecular link between the genetic mutation of fibrillin-1 and disease onset is controversial. The compartmentalization of TGF-β endocytic trafficking has been shown to determine a signaling response in which clathrin-dependent internalization leads to TGF-β signal propagation, and caveolin-1 (CAV-1) associated internalization leads to signal abrogation. We here studied the contribution of endocytic trafficking compartmentalization to increased TGF-β signaling in vascular smooth muscle cells (VSMC) from MFS patients. We examined molecular components involved in clathrin- (SARA, SMAD2) and caveolin-1- (SMAD7, SMURF2) dependent endocytosis. Marfan VSMC showed higher recruitment of SARA and SMAD2 to membranes and their increased interaction with TGF-β receptor II, as well as higher colocalization of SARA with the early endosome marker EEA1. We assessed TGF-β internalization using a biotinylated ligand (b-TGF-β), which colocalized equally with either EEA1 or CAV-1 in VSMC from Marfan patients and controls. However, in Marfan cells, colocalization of b-TGF-β with SARA and EEA1 was increased and accompanied by decreased colocalization with CAV-1 at EEA1-positive endosomes. Moreover, Marfan VSMC showed higher transcriptional levels and membrane enrichment of RAB5. Our results indicate that increased RAB5-associated SARA localization to early endosomes facilitates its TGF-β receptor binding and phosphorylation of signaling mediator SMAD2 in Marfan VSMC. This is accompanied by a reduction of TGF-β sorting into multifunctional vesicles containing cargo from both internalization pathways. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A functional TOC complex contributes to gravity signal transduction in Arabidopsis.

    Science.gov (United States)

    Strohm, Allison K; Barrett-Wilt, Greg A; Masson, Patrick H

    2014-01-01

    Although plastid sedimentation has long been recognized as important for a plant's perception of gravity, it was recently shown that plastids play an additional function in gravitropism. The Translocon at the Outer envelope membrane of Chloroplasts (TOC) complex transports nuclear-encoded proteins into plastids, and a receptor of this complex, Toc132, was previously hypothesized to contribute to gravitropism either by directly functioning as a gravity signal transducer or by indirectly mediating the plastid localization of a gravity signal transducer. Here we show that mutations in multiple genes encoding TOC complex components affect gravitropism in a genetically sensitized background and that the cytoplasmic acidic domain of Toc132 is not required for its involvement in this process. Furthermore, mutations in TOC132 enhance the gravitropic defect of a mutant whose amyloplasts lack starch. Finally, we show that the levels of several nuclear-encoded root proteins are altered in toc132 mutants. These data suggest that the TOC complex indirectly mediates gravity signal transduction in Arabidopsis and support the idea that plastids are involved in gravitropism not only through their ability to sediment but also as part of the signal transduction mechanism.

  17. Contribution of hedgehog signaling to the establishment of left-right asymmetry in the sea urchin.

    Science.gov (United States)

    Warner, Jacob F; Miranda, Esther L; McClay, David R

    2016-03-15

    Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing this larval asymmetry is still a work in progress but involves several conserved signaling pathways including Nodal, and BMP. Here we provide a comprehensive analysis of Hedgehog signaling and it's contribution to left-right asymmetry. We report that Hh signaling plays a conserved role to regulate late asymmetric expression of Nodal and that this regulation occurs after Nodal breaks left-right symmetry in the mesoderm. Thus, while Hh functions to maintain late Nodal expression, the molecular asymmetry of the future coelomic pouches is locked in. Furthermore we report that cilia play a role only insofar as to transduce Hh signaling and do not have an independent effect on the asymmetry of the mesoderm. From this, we are able to construct a more complete regulatory network governing the establishment of left-right asymmetry in the sea urchin. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Phosphatidylcholine contributes to in vivo 31P MRS signal from the human liver

    International Nuclear Information System (INIS)

    Chmelik, Marek; Bogner, Wolfgang; Gajdosik, Martin; Gruber, Stephan; Trattnig, Siegfried; Valkovic, Ladislav; Wolf, Peter; Krebs, Michael; Halilbasic, Emina; Trauner, Michael; Krssak, Martin

    2015-01-01

    To demonstrate the overlap of the hepatic and bile phosphorus ( 31 P) magnetic resonance (MR) spectra and provide evidence of phosphatidylcholine (PtdC) contribution to the in vivo hepatic 31 P MRS phosphodiester (PDE) signal, suggested in previous reports to be phosphoenolpyruvate (PEP). Phantom measurements to assess the chemical shifts of PEP and PtdC signals were performed at 7 T. A retrospective analysis of hepatic 3D 31 P MR spectroscopic imaging (MRSI) data from 18 and five volunteers at 3 T and 7 T, respectively, was performed. Axial images were inspected for the presence of gallbladder, and PDE signals in representative spectra were quantified. Phantom experiments demonstrated the strong pH-dependence of the PEP chemical shift and proved the overlap of PtdC and PEP (∝2 ppm relative to phosphocreatine) at hepatic pH. Gallbladder was covered in seven of 23 in vivo 3D-MRSI datasets. The PDE gall /γ-ATP liver ratio was 4.8-fold higher (p = 0.001) in the gallbladder (PDE gall /γ-ATP liver = 3.61 ± 0.79) than in the liver (PDE liver /γ-ATP liver = 0.75 ± 0.15). In vivo 7 T 31 P MRSI allowed good separation of PDE components. The gallbladder is a strong source of contamination in adjacent 31 P MR hepatic spectra due to biliary phosphatidylcholine. In vivo 31 P MR hepatic signal at 2.06 ppm may represent both phosphatidylcholine and phosphoenolpyruvate, with a higher phosphatidylcholine contribution due to its higher concentration. (orig.)

  19. Dynamic effects of TNF-α on synaptic transmission in mice over time following sciatic nerve chronic constriction injury.

    Science.gov (United States)

    Zhang, Hongmei; Zhang, Haijun; Dougherty, Patrick M

    2013-10-01

    Nerve injury-induced central sensitization can manifest as an increase in excitatory synaptic transmission and/or as a decrease in inhibitory synaptic transmission in spinal dorsal horn neurons. Cytokines such as tumor necrosis factor-α (TNF-α) are induced in the spinal cord under various injury conditions and contribute to neuropathic pain. In this study we examined the effect of TNF-α in modulating excitatory and inhibitory synaptic input to spinal substantia gelatinosa (SG) neurons over time in mice following chronic constriction injury (CCI) of the sciatic nerve. Whole cell patch-clamp studies from SG neurons showed that TNF-α enhanced overall excitability of the spinal cord early in time following nerve injury 3 days after CCI compared with that in sham control mice. In contrast, the effects of TNF were blunted 14 days after CCI in nerve-injured mice compared with sham surgery mice. Immunohistochemical staining showed that the expression of TNF-α receptor 1 (TNFR1) was increased at 3 days but decreased at 14 days following CCI in the ipsilateral vs. the contralateral spinal cord dorsal horn. These results suggest that TNF-α acting at TNFR1 is important in the development of neuropathic pain by facilitating excitatory synaptic signaling in the acute phases after nerve injury but has a reduced effect on spinal neuron signaling in the later phases of nerve injury-induced pain. Failure of the facilatory effects of TNF-α on excitatory synaptic signaling in the dorsal horn to resolve following nerve injury may be an important component in the transition between acute and chronic pain conditions.

  20. SDF1-CXCR4 Signaling Contributes to the Transition from Acute to Chronic Pain State.

    Science.gov (United States)

    Yang, Fei; Sun, Wei; Luo, Wen-Jun; Yang, Yan; Yang, Fan; Wang, Xiao-Liang; Chen, Jun

    2017-05-01

    Emerging evidence has demonstrated the involvement of stromal cell-derived factor 1 (SDF1, also known as CXCL12)-CXCR4 signaling in a variety of pain state. However, the underlying mechanisms of SDF1-CXCR4 signaling leading to the maintenance of chronic pain states are poorly understood. In the present study, we sought to explore the role of SDF1-CXCR4 signaling in the forming of neuroplasticity by applying a model of the transition from acute to chronic pain state, named as hyperalgesic priming. Utilizing intraplantar bee venom (BV) injection, we successfully established hyperalgesic priming state and found that peripheral treating with AMD3100, a CXCR4 antagonist, or knocking down CXCR4 by intraganglionar CXCR4 small interfering RNA (siRNA) injection could prevent BV-induced primary mechanical hyperalgesia and hyperalgesic priming. Moreover, we showed that single intraplantar active SDF1 protein injection is sufficient to induce acute mechanical hyperalgesia and hyperalgesic priming through CXC4. Intraplantar coinjection of ERK inhibitor, U0126, and PI3K inhibitor, LY294002, as well as two protein translation inhibitors, temsirolimus and cordycepin, prevented the development of SDF1-induced acute mechanical hyperalgesia and hyperalgesic priming. Finally, on the models of complete Freund's adjuvant (CFA)-induced chronic inflammatory pain and spared nerve injury (SNI)-induced chronic neuropathic pain, we observed that knock-down of CXCR4 could both prevent the development and reverse the maintenance of chronic pain state. In conclusion, our present data suggested that through regulating ERK and PI3K-AKT pathways-mediated protein translation SDF1-CXCR4 signaling mediates the transition from acute pain to chronic pain state and finally contributes to the development and maintenance of chronic pain.

  1. Mycobacterium tuberculosis lipomannan blocks TNF biosynthesis by regulating macrophage MAPK-activated protein kinase 2 (MK2) and microRNA miR-125b.

    Science.gov (United States)

    Rajaram, Murugesan V S; Ni, Bin; Morris, Jessica D; Brooks, Michelle N; Carlson, Tracy K; Bakthavachalu, Baskar; Schoenberg, Daniel R; Torrelles, Jordi B; Schlesinger, Larry S

    2011-10-18

    Contact of Mycobacterium tuberculosis (M.tb) with the immune system requires interactions between microbial surface molecules and host pattern recognition receptors. Major M.tb-exposed cell envelope molecules, such as lipomannan (LM), contain subtle structural variations that affect the nature of the immune response. Here we show that LM from virulent M.tb (TB-LM), but not from avirulent Myocobacterium smegmatis (SmegLM), is a potent inhibitor of TNF biosynthesis in human macrophages. This difference in response is not because of variation in Toll-like receptor 2-dependent activation of the signaling kinase MAPK p38. Rather, TB-LM stimulation leads to destabilization of TNF mRNA transcripts and subsequent failure to produce TNF protein. In contrast, SmegLM enhances MAPK-activated protein kinase 2 phosphorylation, which is critical for maintaining TNF mRNA stability in part by contributing microRNAs (miRNAs). In this context, human miRNA miR-125b binds to the 3' UTR region of TNF mRNA and destabilizes the transcript, whereas miR-155 enhances TNF production by increasing TNF mRNA half-life and limiting expression of SHIP1, a negative regulator of the PI3K/Akt pathway. We show that macrophages incubated with TB-LM and live M.tb induce high miR-125b expression and low miR-155 expression with correspondingly low TNF production. In contrast, SmegLM and live M. smegmatis induce high miR-155 expression and low miR-125b expression with high TNF production. Thus, we identify a unique cellular mechanism underlying the ability of a major M.tb cell wall component, TB-LM, to block TNF biosynthesis in human macrophages, thereby allowing M.tb to subvert host immunity and potentially increase its virulence.

  2. A hot water extract of Curcuma longa inhibits adhesion molecule protein expression and monocyte adhesion to TNF-α-stimulated human endothelial cells.

    Science.gov (United States)

    Kawasaki, Kengo; Muroyama, Koutarou; Yamamoto, Norio; Murosaki, Shinji

    2015-01-01

    The recruitment of arterial leukocytes to endothelial cells is an important step in the progression of various inflammatory diseases. Therefore, its modulation is thought to be a prospective target for the prevention or treatment of such diseases. Adhesion molecules on endothelial cells are induced by proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), and contribute to the recruitment of leukocytes. In the present study, we investigated the effect of hot water extract of Curcuma longa (WEC) on the protein expression of adhesion molecules, monocyte adhesion induced by TNF-α in human umbilical vascular endothelial cells (HUVECs). Treatment of HUVECs with WEC significantly suppressed both TNF-α-induced protein expression of adhesion molecules and monocyte adhesion. WEC also suppressed phosphorylation and degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) induced by TNF-α in HUVECs, suggesting that WEC inhibits the NF-κB signaling pathway.

  3. Inflammatory factor TNF-α promotes the growth of breast cancer via the positive feedback loop of TNFR1/NF-κB (and/or p38)/p-STAT3/HBXIP/TNFR1.

    Science.gov (United States)

    Cai, Xiaoli; Cao, Can; Li, Jiong; Chen, Fuquan; Zhang, Shuqin; Liu, Bowen; Zhang, Weiying; Zhang, Xiaodong; Ye, Lihong

    2017-08-29

    In the connection between inflammation and cancer development, tumor necrosis factor-alpha (TNF-α) contributes to the tumorigenesis. However, the underlying mechanism remains poorly understood. In this study, we report that TNF-α enhances the growth of breast cancer through up-regulation of oncoprotein hepatitis B X-interacting protein (HBXIP). Our data showed that the levels of TNF-α were positively related to those of HBXIP in clinical breast cancer tissues. Moreover, TNF-α could up-regulate HBXIP in breast cancer cells. Interestingly, silencing of TNF-α receptor 1 (TNFR1) blocked the effect of TNF-α on HBXIP. Mechanistically, we revealed that TNF-α could increase the activities of HBXIP promoter through activating transcriptional factor signal transducer and activator of transcription 3 (STAT3). In addition, nuclear factor kappa B (NF-κB) and/or p38 signaling increased the levels of p-STAT3 in the cells. Strikingly, HBXIP could also up-regulate TNFR1, forming a positive feedback loop of TNFR1/NF-κB (and/or p38)/p-STAT3/HBXIP/TNFR1. Notably, TNF-α was able to up-regulate TNFR1 through driving the loop. In function, we demonstrated that the knockdown of HBXIP remarkably abolished the growth of breast cancer mediated by TNF-α in vitro and in vivo . Thus, we conclude that TNF-α promotes the growth of breast cancer through the positive feedback loop of TNFR1/NF-κB (and/or p38)/p-STAT3/HBXIP/TNFR1.Our finding provides new insights into the mechanism by which TNF-α drives oncoprotein HBXIP in the development of breast cancer.

  4. Dual role of the p75 tumor necrosis factor (TNF) receptor in TNF cytotoxicity

    DEFF Research Database (Denmark)

    Bigda, J; Beletsky, I; Brakebusch, C

    1994-01-01

    to the cytotoxicity of TNF using a wide panel of antibodies (Abs) against the receptor's extracellular domain. Two distinct Ab effects were observed. The Abs triggered signaling for cytotoxicity. This effect: (a) was correlated with the extent of p75-R expression by the cells; (b) was dependent on receptor cross...

  5. Overexpression of miR-130a-3p/301a-3p attenuates high glucose-induced MPC5 podocyte dysfunction through suppression of TNFsignaling.

    Science.gov (United States)

    Jiang, Yan; Wang, Wei; Liu, Zong-Yang; Xie, Yi; Qian, Yuan; Cai, Xue-Ni

    2018-01-01

    Tumor necrosis factor (TNF)-α has been reported to be important in glomerulonephritis, which is closely associated with podocyte dysfunction and apoptosis. However, the precise mechanisms by which TNF-α expression are regulated remain unclear. The purpose of the present study was to investigate the role of microRNA (miR)-130a-3p/301a-3p in the post-transcriptional control of TNF-α expression and high glucose (HG)-induced podocyte dysfunction. Mice MPC5 podocytes were incubated with HG and transfected with miR-130a-3p/301a-3p mimics or inhibitors, reactive oxygen species (ROS) levels were measured by flow cytometry assay, and the mRNA and protein levels were assayed by using reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The targeted genes were predicted by a bioinformatics algorithm and verified using a dual luciferase reporter assay. It was observed that miR-130a-3p/301a-3p was a novel regulator of TNF-α in mouse podocytes. miR-130a-3p/301a-3p mimics inhibited TNF-α 3'-untranslated region luciferase reporter activity, in addition to endogenous TNF-α protein expression. Furthermore, forced expression of miR-130a-3p or miR-301a-3p resulted in the downregulation of ROS and malondialdehyde (MDA) and the upregulation of superoxide dismutase (SOD) 1 in the presence of HG. Inhibition of TNF-α level prevented a remarkable reduction in SOD activity and a marked increase in ROS and MDA levels in HG-treated podocytes. Furthermore, TNF-α loss-of-function significantly reversed HG-induced podocyte apoptosis. These data demonstrated a novel up-stream role for miR-130a-3p/301a-3p in TNF-α-mediated podocyte dysfunction and apoptosis in the presence of HG.

  6. Estrogen signaling modulates allergic inflammation and contributes to sex differences in asthma.

    Directory of Open Access Journals (Sweden)

    Aleksander eKeselman

    2015-11-01

    Full Text Available Asthma is a chronic airway inflammatory disease that afflicts approximately 300 million people worldwide. It is characterized by airway constriction that leads to wheezing, coughing, and shortness of breath. The most common treatments are corticosteroids and β2-adrenergic receptor antagonists, which target inflammation and airway smooth muscle constriction, respectively. The incidence and severity of asthma is greater in women than in men, and women are more prone to develop corticosteroid-resistant or hard-to-treat asthma. Puberty, menstruation, pregnancy, menopause, and oral contraceptives are known to contribute to disease outcome in women, potentially suggesting a role for estrogen and other hormones impacting allergic inflammation. Currently, the mechanisms underlying these sex differences are poorly understood, although the effect of sex hormones, such as estrogen, on allergic inflammation is gaining interest. Asthma presents as a heterogeneous disease. In typical Th2-type allergic asthma, interleukin-4 and interleukin-13 predominate, driving IgE production and recruitment of eosinophils into the lungs. Chronic Th2-inflammation in the lung results in structural changes and activation of multiple immune cell types, leading to a deterioration of lung function over time. Most immune cells express estrogen receptors (ERα, ERβ, or the membrane-bound G-protein-coupled estrogen receptor to varying degrees and can respond to the hormone. Together these receptors have demonstrated the capacity to regulate a spectrum of immune functions, including adhesion, migration, survival, wound healing, and antibody and cytokine production. This review will cover the current understanding of estrogen signaling in allergic inflammation and discuss how this signaling may contribute to sex differences in asthma and allergy.

  7. Relative contributions of norspermidine synthesis and signaling pathways to the regulation of Vibrio cholerae biofilm formation.

    Science.gov (United States)

    Wotanis, Caitlin K; Brennan, William P; Angotti, Anthony D; Villa, Elizabeth A; Zayner, Josiah P; Mozina, Alexandra N; Rutkovsky, Alexandria C; Sobe, Richard C; Bond, Whitney G; Karatan, Ece

    2017-01-01

    The polyamine norspermidine is one of the major polyamines synthesized by Vibrionales and has also been found in various aquatic organisms. Norspermidine is among the environmental signals that positively regulate Vibrio cholerae biofilm formation. The NspS/MbaA signaling complex detects extracellular norspermidine and mediates the response to this polyamine. Norspermidine binding to the NspS periplasmic binding protein is thought to inhibit the phosphodiesterase activity of MbaA, increasing levels of the biofilm-promoting second messenger cyclic diguanylate monophosphate, thus enhancing biofilm formation. V. cholerae can also synthesize norspermidine using the enzyme NspC as well as import it from the environment. Deletion of the nspC gene was shown to reduce accumulation of bacteria in biofilms, leading to the conclusion that intracellular norspermidine is also a positive regulator of biofilm formation. Because V. cholerae uses norspermidine to synthesize the siderophore vibriobactin it is possible that intracellular norspermidine is required to obtain sufficient amounts of iron, which is also necessary for robust biofilm formation. The objective of this study was to assess the relative contributions of intracellular and extracellular norspermidine to the regulation of biofilm formation in V. cholerae. We show the biofilm defect of norspermidine synthesis mutants does not result from an inability to produce vibriobactin as vibriobactin synthesis mutants do not have diminished biofilm forming abilities. Furthermore, our work shows that extracellular, but not intracellular norspermidine, is mainly responsible for promoting biofilm formation. We establish that the NspS/MbaA signaling complex is the dominant mediator of biofilm formation in response to extracellular norspermidine, rather than norspermidine synthesized by NspC or imported into the cell.

  8. Otolith signals contribute to inter-individual differences in the perception of gravity-centered space.

    Science.gov (United States)

    Cian, C; Barraud, P A; Paillard, A C; Hidot, S; Denise, P; Ventre-Dominey, J

    2014-03-01

    The aim of the present study was to investigate (1) the relative contribution of the egocentric reference as well as body orientation perception to visual horizon percept during tilt or during increased gravito-inertial acceleration (GiA, hypergravity environment) conditions and (2) the role of vestibular signals in the inter-individual differences observed in these perceptual modalities. Perceptual estimates analysis showed that backward tilt induced (1) an elevation of the visual horizon, (2) an elevation of the egocentric estimation (visual straight ahead) and (3) an overestimation of body tilt. The increase in the magnitude of GiA induced (1) a lowering of the apparent horizon, (2) a lowering of the straight ahead and (3) a perception of backward tilt. Overall, visual horizon percept can be expressed as the combination of body orientation perception and egocentric estimation. When assessing otolith reactivity using off-vertical axis rotation (OVAR), only visual egocentric estimation was significantly correlated with horizontal OVAR performance. On the one hand, we found a correlation between a low modulation amplitude of the otolith responses and straight ahead accuracy when the head axis was tilted relative to gravity. On the other hand, the bias of otolith responses was significantly correlated with straight ahead accuracy when subjects were submitted to an increase in the GiA. Thus, straight ahead sense would be dependent to some extent to otolith function. These results are discussed in terms of the contribution of otolith inputs in the overall multimodal integration subtending spatial constancy.

  9. Resolving the contribution of the uncoupled phycobilisomes to cyanobacterial pulse-amplitude modulated (PAM) fluorometry signals.

    Science.gov (United States)

    Acuña, Alonso M; Snellenburg, Joris J; Gwizdala, Michal; Kirilovsky, Diana; van Grondelle, Rienk; van Stokkum, Ivo H M

    2016-01-01

    Pulse-amplitude modulated (PAM) fluorometry is extensively used to characterize photosynthetic organisms on the slow time-scale (1-1000 s). The saturation pulse method allows determination of the quantum yields of maximal (F(M)) and minimal fluorescence (F(0)), parameters related to the activity of the photosynthetic apparatus. Also, when the sample undergoes a certain light treatment during the measurement, the fluorescence quantum yields of the unquenched and the quenched states can be determined. In the case of cyanobacteria, however, the recorded fluorescence does not exclusively stem from the chlorophyll a in photosystem II (PSII). The phycobilins, the pigments of the cyanobacterial light-harvesting complexes, the phycobilisomes (PB), also contribute to the PAM signal, and therefore, F(0) and F(M) are no longer related to PSII only. We present a functional model that takes into account the presence of several fluorescent species whose concentrations can be resolved provided their fluorescence quantum yields are known. Data analysis of PAM measurements on in vivo cells of our model organism Synechocystis PCC6803 is discussed. Three different components are found necessary to fit the data: uncoupled PB (PB(free)), PB-PSII complexes, and free PSI. The free PSII contribution was negligible. The PB(free) contribution substantially increased in the mutants that lack the core terminal emitter subunits allophycocyanin D or allophycocyanin F. A positive correlation was found between the amount of PB(free) and the rate constants describing the binding of the activated orange carotenoid protein to PB, responsible for non-photochemical quenching.

  10. Serotonin 5-HT2A receptor activation blocks TNF-α mediated inflammation in vivo.

    Directory of Open Access Journals (Sweden)

    Felix Nau

    Full Text Available Tumor necrosis factor alpha (TNF-α plays a key role in inflammation, and its production and signaling contribute to many inflammatory related diseases. Recently, we discovered that selective activation of serotonin 5-HT2A receptors with the agonist (R-DOI produces a super-potent blockade of proinflammatory markers in primary rat aortic smooth muscle cells. Here, we demonstrate that systemic administration of (R-DOI can block the systemic effects of TNF-α in whole animal, with potent anti-inflammatory effects in the aortic arch and small intestine. This includes blockade of TNF-α-induced expression of pro-inflammatory cell adhesion (Icam-1, Vcam-1, cytokine (Il-6, IL-1b, and chemokine (Mcp-1, Cx3cl1 genes, and expression of VCAM-1 protein in the intestine. Further, systemic (R-DOI also prevents the TNF-α-induced increase of circulating IL-6. Importantly, utilizing receptor selective antagonists, we have demonstrated that the mechanism underlying the systemic anti-inflammatory effects of (R-DOI is activation of serotonin 5-HT2A receptors. Our results highlight a powerful new role for the serotonin 5-HT2A receptor in inflammatory processes, and indicate that agonism of serotonin receptors may represent an effective and novel approach to develop powerful small molecule therapeutics for inflammatory diseases and conditions such as atherosclerosis and inflammatory bowel disease.

  11. Serotonin 5-HT2A receptor activation blocks TNF-α mediated inflammation in vivo.

    Science.gov (United States)

    Nau, Felix; Yu, Bangning; Martin, David; Nichols, Charles D

    2013-01-01

    Tumor necrosis factor alpha (TNF-α) plays a key role in inflammation, and its production and signaling contribute to many inflammatory related diseases. Recently, we discovered that selective activation of serotonin 5-HT2A receptors with the agonist (R)-DOI produces a super-potent blockade of proinflammatory markers in primary rat aortic smooth muscle cells. Here, we demonstrate that systemic administration of (R)-DOI can block the systemic effects of TNF-α in whole animal, with potent anti-inflammatory effects in the aortic arch and small intestine. This includes blockade of TNF-α-induced expression of pro-inflammatory cell adhesion (Icam-1, Vcam-1), cytokine (Il-6, IL-1b), and chemokine (Mcp-1, Cx3cl1) genes, and expression of VCAM-1 protein in the intestine. Further, systemic (R)-DOI also prevents the TNF-α-induced increase of circulating IL-6. Importantly, utilizing receptor selective antagonists, we have demonstrated that the mechanism underlying the systemic anti-inflammatory effects of (R)-DOI is activation of serotonin 5-HT2A receptors. Our results highlight a powerful new role for the serotonin 5-HT2A receptor in inflammatory processes, and indicate that agonism of serotonin receptors may represent an effective and novel approach to develop powerful small molecule therapeutics for inflammatory diseases and conditions such as atherosclerosis and inflammatory bowel disease.

  12. A platelet-activating factor (PAF) receptor deficiency exacerbates diet-induced obesity but PAF/PAF receptor signaling does not contribute to the development of obesity-induced chronic inflammation.

    Science.gov (United States)

    Yamaguchi, Masahiko; Matsui, Masakazu; Higa, Ryoko; Yamazaki, Yasuhiro; Ikari, Akira; Miyake, Masaki; Miwa, Masao; Ishii, Satoshi; Sugatani, Junko; Shimizu, Takao

    2015-02-15

    Platelet-activating factor (PAF) is a well-known phospholipid that mediates acute inflammatory responses. In the present study, we investigated whether PAF/PAF receptor signaling contributed to chronic inflammation in the white adipose tissue (WAT) of PAF receptor-knockout (PAFR-KO) mice. Body and epididymal WAT weights were higher in PAFR-KO mice fed a high-fat diet (HFD) than in wild-type (WT) mice. TNF-α mRNA expression levels in epididymal WAT and the infiltration of CD11c-positive macrophages into epididymal WAT, which led to chronic inflammation, were also elevated in HFD-fed PAFR-KO mice. HFD-fed PAFR-KO mice had higher levels of fasting serum glucose than HFD-fed WT mice as well as impaired glucose tolerance. Although PAF receptor signaling up-regulated the expression of TNF-α and lipopolysaccharide induced the expression of acyl-CoA:lysophosphatidylcholine acyltransferase 2 (LPCAT2) mRNA in bone marrow-derived macrophages, no significant differences were observed in the expression of LPCAT2 mRNA and PAF levels in epididymal WAT between HFD-fed mice and normal diet-fed mice. In addition to our previous finding in which energy expenditure in PAF receptor (PAFR)-deficient mice was low due to impaired brown adipose tissue function, the present study demonstrated that PAF/PAF receptor signaling up-regulated the expression of Ucp1 mRNA, which is essential for cellular thermogenesis, in 3T3-L1 adipocytes. We concluded that the marked accumulation of abdominal fat due to HFD feeding led to more severe chronic inflammation in WAT, which is associated with glucose metabolism disorders, in PAFR-KO mice than in WT mice, and PAF/PAF receptor signaling may regulate energy expenditure and adiposity. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. NADPH oxidase/ROS-dependent PYK2 activation is involved in TNF-α-induced matrix metalloproteinase-9 expression in rat heart-derived H9c2 cells

    International Nuclear Information System (INIS)

    Yang, Chuen-Mao; Lee, I-Ta; Hsu, Ru-Chun; Chi, Pei-Ling; Hsiao, Li-Der

    2013-01-01

    TNF-α plays a mediator role in the pathogenesis of chronic heart failure contributing to cardiac remodeling and peripheral vascular disturbances. The implication of TNF-α in inflammatory responses has been shown to be mediated through up-regulation of matrix metalloproteinase-9 (MMP-9). However, the detailed mechanisms of TNF-α-induced MMP-9 expression in rat embryonic-heart derived H9c2 cells are largely not defined. We demonstrated that in H9c2 cells, TNF-α induced MMP-9 mRNA and protein expression associated with an increase in the secretion of pro-MMP-9. TNF-α-mediated responses were attenuated by pretreatment with the inhibitor of ROS (N-acetyl-L-cysteine, NAC), NADPH oxidase [apocynin (APO) or diphenyleneiodonium chloride (DPI)], MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), NF-κB (Bay11-7082), or PYK2 (PF-431396) and transfection with siRNA of TNFR1, p47 phox , p42, p38, JNK1, p65, or PYK2. Moreover, TNF-α markedly induced NADPH oxidase-derived ROS generation in these cells. TNF-α-enhanced p42/p44 MAPK, p38 MAPK, JNK1/2, and NF-κB (p65) phosphorylation and in vivo binding of p65 to the MMP-9 promoter were inhibited by U0126, SB202190, SP600125, NAC, DPI, or APO. In addition, TNF-α-mediated PYK2 phosphorylation was inhibited by NAC, DPI, or APO. PYK2 inhibition could reduce TNF-α-stimulated MAPKs and NF-κB activation. Thus, in H9c2 cells, we are the first to show that TNF-α-induced MMP-9 expression is mediated through a TNFR1/NADPH oxidase/ROS/PYK2/MAPKs/NF-κB cascade. We demonstrated that NADPH oxidase-derived ROS generation is involved in TNF-α-induced PYK2 activation in these cells. Understanding the regulation of MMP-9 expression and NADPH oxidase activation by TNF-α on H9c2 cells may provide potential therapeutic targets of chronic heart failure. - Highlights: • TNF-α induces MMP-9 secretion and expression via a TNFR1-dependent pathway. • TNF-α induces ROS/PYK2-dependent MMP-9 expression in H9c2 cells. • TNF-α induces

  14. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine.

    Science.gov (United States)

    Leach, Prescott T; Gould, Thomas J

    2015-10-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to the addictive liability of nicotine. Nicotine modulates aspects of the endocrine system, including the thyroid, which is critical for normal cognitive functioning. It is possible that nicotine's effects on thyroid function may alter learning and memory, and this may underlie some of its addictive potential. Here, we review the literature on thyroid function and cognition, with a focus on how nicotine alters thyroid hormone signaling and the potential impact on cognition. Changes in cognition are a major symptom of nicotine addiction. Current anti-smoking therapies have modest success at best. If some of the cognitive effects of nicotine are mediated through the thyroid hormone system, then thyroid hormone agonists may be novel treatments for smoking cessation therapies. The content of this review is important because it clarifies the relationship between smoking and thyroid function, which has been ill-defined in the past. This review is timely because the reduction in smoking rates we have seen in recent decades, due to public awareness campaigns and public smoking bans, has leveled off in recent years. Therefore, novel treatment approaches are needed to help reduce smoking rates further. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Regulatory cross-talks and cascades in rice hormone biosynthesis pathways contribute to stress signaling

    Directory of Open Access Journals (Sweden)

    Arindam Deb

    2016-08-01

    Full Text Available Crosstalk among different hormone signaling pathways play an important role in modulating plant response to both biotic and abiotic stress. Hormone activity is controlled by its bio-availability, which is again influenced by its biosynthesis. Thus independent hormone biosynthesis pathways must be regulated and co-ordinated to mount an integrated response. One of the possibilities is to use cis-regulatory elements to orchestrate expression of hormone biosynthesis genes. Analysis of CREs, associated with differentially expressed hormone biosynthesis related genes in rice leaf under Magnaporthe oryzae attack and drought stress enabled us to obtain insights about cross-talk among hormone biosynthesis pathways at the transcriptional level. We identified some master transcription regulators that co-ordinate different hormone biosynthesis pathways under stress. We found that Abscisic acid and Brassinosteroid regulate Cytokinin conjugation; conversely Brassinosteroid biosynthesis is affected by both Abscisic acid and Cytokinin. Jasmonic acid and Ethylene biosynthesis may be modulated by Abscisic acid through DREB transcription factors. Jasmonic acid or Salicylic acid biosynthesis pathways are co-regulated but they are unlikely to influence each other’s production directly. Thus multiple hormones may modulate hormone biosynthesis pathways through a complex regulatory network, where biosynthesis of one hormone is affected by several other contributing hormones.

  16. Proinflammatory Cytokines IL-6 and TNF-α Increased Telomerase Activity through NF-κB/STAT1/STAT3 Activation, and Withaferin A Inhibited the Signaling in Colorectal Cancer Cells

    Directory of Open Access Journals (Sweden)

    Seyung S. Chung

    2017-01-01

    Full Text Available There are increasing evidences of proinflammatory cytokine involvement in cancer development. Here, we found that two cytokines, IL-6 and TNF-α, activated colorectal cancer cells to be more invasive and stem-like. Combined treatment of IL-6 and TNF-α phosphorylated transcription factors STAT3 in a synergistic manner. STAT3, STAT1, and NF-κB physically interacted upon the cytokine stimulation. STAT3 was bound to the promoter region of human telomerase reverse transcriptase (hTERT. IL-6 and TNF-α stimulation further enhanced STAT3 binding affinity. Stem cell marker Oct-4 was upregulated in colorectal cancer cells upon IL-6 and TNF-α stimulation. Withaferin A, an anti-inflammatory steroidal lactone, inhibited the IL-6- and TNF-α-induced cancer cell invasion and decreased colonosphere formation. Notably, withaferin A inhibited STAT3 phosphorylation and abolished the STAT3, STAT1, and NF-κB interactions. Oct-4 expression was also downregulated by withaferin A inhibition. The binding of STAT3 to the hTERT promoter region and telomerase activity showed reduction with withaferin A treatments. Proinflammatory cytokine-induced cancer cell invasiveness is mediated by a STAT3-regulated mechanism in colorectal cancer cells. Our data suggest that withaferin A could be a promising anticancer agent that effectively inhibits the progression of colorectal cancer.

  17. TNF RECEPTOR 2 AND DISEASE: Autoimmunity and Regenerative Medicine

    Directory of Open Access Journals (Sweden)

    Denise Louise Faustman

    2013-12-01

    Full Text Available The regulatory cytokine tumor necrosis factor (TNF exerts its effects through two receptors: TNFR1 and TNFR2. Defects in TNFR2 signaling are evident in a variety of autoimmune diseases. One new treatment strategy for autoimmune disease is selective destruction of autoreactive T cells by administration of TNF, TNF inducers, or TNFR2 agonism. A related strategy is to rely on TNFR2 agonism to induce T regulatory cells (Tregs that suppress cytotoxic T cells. Targeting TNFR2 as a treatment strategy is likely superior to TNFR1 because of its more limited cellular distribution on T cells, subsets of neurons, and a few other cell types, whereas TNFR1 is expressed throughout the body. This review focuses on TNFR2 expression, structure, and signaling; TNFR2 signaling in autoimmune disease and treatment strategies targeting TNFR2 in autoimmunity and the potential for TNFR2 to facilitate end organ regeneration.

  18. [Enrichment of extracellular DNA from the cultivation medium of human peripheral blood mononuclears with genomic CpG rich fragments results in increased cell production of IL-6 and TNF-a via activation of the NF-kB signaling pathway].

    Science.gov (United States)

    Speranskii, A I; Kostyuk, S V; Kalashnikova, E A; Veiko, N N

    2016-03-01

    Previously, it was found that blood plasma extracellular DNA (ecDNA) of patients with rheumatoid arthritis (RA) is enriched with CpG-rich genomic DNA fragments, which contain TLR9 ligands (Veiko et al., 2006). In this study we have demonstrated that ecDNA of a RA patient and model fragments added to a cultivation medium of peripheral blood mononuclear cells (PBMC) of healthy donors stimulate expression of genes for the TLR9-MyD88-NF-kB signaling pathway; this leads to a significant increase in concentrations of the proinflammatory cytokines IL-6 and TNF-a in the cultivation medium. Human genomic DNA non-enriched with the CpG sequences did not stimulate IL-6 and TNF-a synthesis in PBMC. A scheme explaining the potential role ecDNA in the induction and maintenance of increased levels of the proinflammatory cytokines under conditions damaging the human cells has been proposed.

  19. TNF Counterbalances the Emergence of M2 Tumor Macrophages

    Directory of Open Access Journals (Sweden)

    Franz Kratochvill

    2015-09-01

    Full Text Available Cancer can involve non-resolving, persistent inflammation where varying numbers of tumor-associated macrophages (TAMs infiltrate and adopt different activation states between anti-tumor M1 and pro-tumor M2 phenotypes. Here, we resolve a cascade causing differential macrophage phenotypes in the tumor microenvironment. Reduction in TNF mRNA production or loss of type I TNF receptor signaling resulted in a striking pattern of enhanced M2 mRNA expression. M2 gene expression was driven in part by IL-13 from eosinophils co-recruited with inflammatory monocytes, a pathway that was suppressed by TNF. Our data define regulatory nodes within the tumor microenvironment that balance M1 and M2 populations. Our results show macrophage polarization in cancer is dynamic and dependent on the balance between TNF and IL-13, thus providing a strategy for manipulating TAMs.

  20. Anti-TNF-α biotherapies

    DEFF Research Database (Denmark)

    Bendtzen, Klaus

    2012-01-01

    This article discusses the rationale behind recommending immunopharmacological guidance of long-term therapies with genetically engineered anti-TNF-α immunoglobulin constructs. Arguments why therapeutic decision-making should not rely on clinical outcome alone are presented. Central...... to this is that the use of theranostics (i.e., monitoring circulating levels of functional anti-TNF-α drugs and antidrug antibodies) would markedly improve treatment because therapies can be tailored to individual patients and provide more effective and economical long-term therapies with minimal risk of side effects....... Large-scale immunopharmacological knowledge of how patients 'handle' TNF-α biopharmaceuticals would also help industry develop more effective and safer TNF-α inhibitors....

  1. Regulation of tumour necrosis factor (TNF) induced apoptosis by soluble TNF receptors in Helicobacter pylori infection

    OpenAIRE

    Shibata, J; Goto, H; Arisawa, T; Niwa, Y; Hayakawa, T; Nakayama, A; Mori, N

    1999-01-01

    BACKGROUND—Tumour necrosis factor (TNF) is a predominant cytokine produced in the gastric mucosa of patients with Helicobacter pylori infection. TNF induces apoptosis in a variety of cells. The soluble TNF receptors (sTNF-Rs) can be divided into sTNF-RI and sTNF-RII, both of which inhibit TNF activity. However, their precise mechanisms remain unclear.
AIM—To investigate the role of sTNF-Rs in H pylori infection.
METHODS—In 40 patients, production of TNF and sTNF-Rs in gastric mucosa was measu...

  2. Disruption of Axonal Transport Perturbs Bone Morphogenetic Protein (BMP) - Signaling and Contributes to Synaptic Abnormalities in Two Neurodegenerative Diseases

    Science.gov (United States)

    Kang, Min Jung; Hansen, Timothy J.; Mickiewicz, Monique; Kaczynski, Tadeusz J.; Fye, Samantha; Gunawardena, Shermali

    2014-01-01

    Formation of new synapses or maintenance of existing synapses requires the delivery of synaptic components from the soma to the nerve termini via axonal transport. One pathway that is important in synapse formation, maintenance and function of the Drosophila neuromuscular junction (NMJ) is the bone morphogenetic protein (BMP)-signaling pathway. Here we show that perturbations in axonal transport directly disrupt BMP signaling, as measured by its downstream signal, phospho Mad (p-Mad). We found that components of the BMP pathway genetically interact with both kinesin-1 and dynein motor proteins. Thick vein (TKV) vesicle motility was also perturbed by reductions in kinesin-1 or dynein motors. Interestingly, dynein mutations severely disrupted p-Mad signaling while kinesin-1 mutants showed a mild reduction in p-Mad signal intensity. Similar to mutants in components of the BMP pathway, both kinesin-1 and dynein motor protein mutants also showed synaptic morphological defects. Strikingly TKV motility and p-Mad signaling were disrupted in larvae expressing two human disease proteins; expansions of glutamine repeats (polyQ77) and human amyloid precursor protein (APP) with a familial Alzheimer's disease (AD) mutation (APPswe). Consistent with axonal transport defects, larvae expressing these disease proteins showed accumulations of synaptic proteins along axons and synaptic abnormalities. Taken together our results suggest that similar to the NGF-TrkA signaling endosome, a BMP signaling endosome that directly interacts with molecular motors likely exist. Thus problems in axonal transport occurs early, perturbs BMP signaling, and likely contributes to the synaptic abnormalities observed in these two diseases. PMID:25127478

  3. Disruption of axonal transport perturbs bone morphogenetic protein (BMP)--signaling and contributes to synaptic abnormalities in two neurodegenerative diseases.

    Science.gov (United States)

    Kang, Min Jung; Hansen, Timothy J; Mickiewicz, Monique; Kaczynski, Tadeusz J; Fye, Samantha; Gunawardena, Shermali

    2014-01-01

    Formation of new synapses or maintenance of existing synapses requires the delivery of synaptic components from the soma to the nerve termini via axonal transport. One pathway that is important in synapse formation, maintenance and function of the Drosophila neuromuscular junction (NMJ) is the bone morphogenetic protein (BMP)-signaling pathway. Here we show that perturbations in axonal transport directly disrupt BMP signaling, as measured by its downstream signal, phospho Mad (p-Mad). We found that components of the BMP pathway genetically interact with both kinesin-1 and dynein motor proteins. Thick vein (TKV) vesicle motility was also perturbed by reductions in kinesin-1 or dynein motors. Interestingly, dynein mutations severely disrupted p-Mad signaling while kinesin-1 mutants showed a mild reduction in p-Mad signal intensity. Similar to mutants in components of the BMP pathway, both kinesin-1 and dynein motor protein mutants also showed synaptic morphological defects. Strikingly TKV motility and p-Mad signaling were disrupted in larvae expressing two human disease proteins; expansions of glutamine repeats (polyQ77) and human amyloid precursor protein (APP) with a familial Alzheimer's disease (AD) mutation (APPswe). Consistent with axonal transport defects, larvae expressing these disease proteins showed accumulations of synaptic proteins along axons and synaptic abnormalities. Taken together our results suggest that similar to the NGF-TrkA signaling endosome, a BMP signaling endosome that directly interacts with molecular motors likely exist. Thus problems in axonal transport occurs early, perturbs BMP signaling, and likely contributes to the synaptic abnormalities observed in these two diseases.

  4. The role of TNF-α and TNF-β gene polymorphism in the pathogenesis of Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Hannan Al- Rayes

    2013-01-01

    Full Text Available Rheumatoid arthritis (RA is a chronic systemic inflammatory disorder of unknown etiology that affects the synovial membrane of multiple joints. The clinical presentation of RA may vary from mild to severe with excessive erosions of periarticular bone leading to the loss of functional capacity. Both genetic and environmental factors are important in the development of this disorder. The genetic contribution to susceptibility for RA is underlined by a three-to four-fold higher concordance percentage for clinically expressed disease in monozygotic twins compared to dizygotic twins. The severity and long term outcome of RA have also been related to various genetic factors. Tumor necrosis factor (TNF, a pro-inflammatory cytokine, is involved in the pathogenesis of a variety of autoimmune disorders, including RA. A large number of studies have been undertaken to determine the role of TNF-α promoter polymorphisms in the pathogenesis of RA. On the other hand few attempts have been made to identify the association between TNF-α (lymphotoxin-alfa polymorphism and RA. In this narrative review of published literature, an attempt has been made to determine the association between TNF-α promoter polymorphisms at positions –308, –238, –489, –857, –863 and TNF-β at +252 with respect to susceptibility to and severity of RA, as well as response to drug therapy. In spite of intra-and inter-ethnic variations, analysis of data suggests a significant role of TNF-α/TNF-β polymorphisms in determining the susceptibility/severity of RA and responsiveness to anti-TNF drug therapy. The TNF gene polymorphisms may be an interesting target for novel strategies to prevent RA and/or in its early treatment. Further studies using larger samples are needed to pinpoint the regulatory polymorphisms or haplotypes and their effects on the development of certain manifestations in RA.

  5. Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

    Directory of Open Access Journals (Sweden)

    Christopher James CLARK

    2011-04-01

    Full Text Available Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone (hft, a low frequency tone (lft, and atonal sound pulses (asp, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices (tail-feathers of wild males impaired production of the lft and asp but not the hft or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds similar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism [Current Zoology 57 (2: 187–196, 2011].

  6. TNF Superfamily: A Growing Saga of Kidney Injury Modulators

    Directory of Open Access Journals (Sweden)

    Maria D. Sanchez-Niño

    2010-01-01

    Full Text Available Members of the TNF superfamily participate in kidney disease. Tumor necrosis factor (TNF and Fas ligand regulate renal cell survival and inflammation, and therapeutic targeting improves the outcome of experimental renal injury. TNF-related apoptosis-inducing ligand (TRAIL and its potential decoy receptor osteoprotegerin are the two most upregulated death-related genes in human diabetic nephropathy. TRAIL activates NF-kappaB in tubular cells and promotes apoptosis in tubular cells and podocytes, especially in a high-glucose environment. By contrast, osteoprotegerin plays a protective role against TRAIL-induced apoptosis. Another family member, TNF-like weak inducer of apoptosis (TWEAK induces inflammation and tubular cell death or proliferation, depending on the microenvironment. While TNF only activates canonical NF-kappaB signaling, TWEAK promotes both canonical and noncanonical NF-kappaB activation in tubular cells, regulating different inflammatory responses. TWEAK promotes the secretion of MCP-1 and RANTES through NF-kappaB RelA-containing complexes and upregulates CCl21 and CCL19 expression through NF-kappaB inducing kinase (NIK- dependent RelB/NF-kappaB2 complexes. In vivo TWEAK promotes postnephrectomy compensatory renal cell proliferation in a noninflammatory milieu. However, in the inflammatory milieu of acute kidney injury, TWEAK promotes tubular cell death and inflammation. Therapeutic targeting of TNF superfamily cytokines, including multipronged approaches targeting several cytokines should be further explored.

  7. THE CONTRIBUTION OF HALO WHITE DWARF BINARIES TO THE LASER INTERFEROMETER SPACE ANTENNA SIGNAL

    International Nuclear Information System (INIS)

    Ruiter, Ashley J.; Belczynski, Krzysztof; Benacquista, Matthew; Holley-Bockelmann, Kelly

    2009-01-01

    Galactic double white dwarfs were postulated as a source of confusion limited noise for the Laser Interferometer Space Antenna (LISA), the future space-based gravitational wave observatory. Until very recently, the Galactic population consisted of a relatively well-studied disk population, a somewhat studied smaller bulge population and a mostly unknown, but potentially large halo population. It has been argued that the halo population may produce a signal that is much stronger (factor of ∼5 in spectral amplitude) than the disk population. However, this surprising result was not based on an actual calculation of a halo white dwarf population, but was derived on (1) the assumption that one can extrapolate the halo population properties from those of the disk population and (2) the postulated (unrealistically) high number of white dwarfs in the halo. We perform the first calculation of a halo white dwarf population using population synthesis models. Our comparison with the signal arising from double white dwarfs in the Galactic disk+bulge clearly shows that it is impossible for the double white dwarf halo signal to exceed that of the rest of the Galaxy. Using microlensing results to give an upper limit on the content of white dwarfs in the halo (∼30% baryonic mass in white dwarfs), our predicted halo signal is a factor of 10 lower than the disk+bulge signal. Even in the implausible case, where all of the baryonic halo mass is found in white dwarfs, the halo signal does not become comparable to that of the disk+bulge, and thus would still have a negligible effect on the detection of other LISA sources.

  8. Larval vision contributes to gregarious settlement in barnacles: adult red fluorescence as a possible visual signal

    KAUST Repository

    Matsumura, K.

    2014-02-26

    Gregarious settlement, an essential behavior for many barnacle species that can only reproduce by mating with a nearby barnacle, has long been thought to rely on larval ability to recognize chemical signals from conspecifics during settlement. However, the cyprid, the settlement stage larva in barnacles, has one pair of compound eyes that appear only at the late nauplius VI and cyprid stages, but the function(s) of these eyes remains unknown. Here we show that cyprids of the intertidal barnacle Balanus (=Amphibalanus) amphitrite can locate adult barnacles even in the absence of chemical cues, and prefer to settle around them probably via larval sense of vision. We also show that the cyprids can discriminate color and preferred to settle on red surfaces. Moreover, we found that shells of adult B. amphitrite emit red auto-fluorescence and the adult extracts with the fluorescence as a visual signal attracted cyprid larvae to settle around it. We propose that the perception of specific visual signals can be involved in behavior of zooplankton including marine invertebrate larvae, and that barnacle auto-fluorescence may be a specific signal involved in gregarious larval settlement.

  9. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine

    OpenAIRE

    Leach, Prescott T.; Gould, Thomas J.

    2015-01-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to...

  10. Differential contribution of key metabolic substrates and cellular oxygen in HIF signalling

    Energy Technology Data Exchange (ETDEWEB)

    Zhdanov, Alexander V., E-mail: a.zhdanov@ucc.ie [School of Biochemistry and Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork (Ireland); Waters, Alicia H.C. [School of Biochemistry and Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork (Ireland); Golubeva, Anna V. [Alimentary Pharmabiotic Centre, University College Cork, Bioscience Institute, Western Road, Cork (Ireland); Papkovsky, Dmitri B. [School of Biochemistry and Cell Biology, University College Cork, Cavanagh Pharmacy Building, College Road, Cork (Ireland)

    2015-01-01

    Changes in availability and utilisation of O{sub 2} and metabolic substrates are common in ischemia and cancer. We examined effects of substrate deprivation on HIF signalling in PC12 cells exposed to different atmospheric O{sub 2}. Upon 2–4 h moderate hypoxia, HIF-α protein levels were dictated by the availability of glutamine and glucose, essential for deep cell deoxygenation and glycolytic ATP flux. Nuclear accumulation of HIF-1α dramatically decreased upon inhibition of glutaminolysis or glutamine deprivation. Elevation of HIF-2α levels was transcription-independent and associated with the activation of Akt and Erk1/2. Upon 2 h anoxia, HIF-2α levels strongly correlated with cellular ATP, produced exclusively via glycolysis. Without glucose, HIF signalling was suppressed, giving way to other regulators of cell adaptation to energy crisis, e.g. AMPK. Consequently, viability of cells deprived of O{sub 2} and glucose decreased upon inhibition of AMPK with dorsomorphin. The capacity of cells to accumulate HIF-2α decreased after 24 h glucose deprivation. This effect, associated with increased AMPKα phosphorylation, was sensitive to dorsomorphin. In chronically hypoxic cells, glutamine played no major role in HIF-2α accumulation, which became mainly glucose-dependent. Overall, the availability of O{sub 2} and metabolic substrates intricately regulates HIF signalling by affecting cell oxygenation, ATP levels and pathways involved in production of HIF-α. - Highlights: • Gln and Glc regulate HIF levels in hypoxic cells by maintaining low O{sub 2} and high ATP. • HIF-α levels under anoxia correlate with cellular ATP and critically depend on Glc. • Gln and Glc modulate activity of Akt, Erk and AMPK, regulating HIF production. • HIF signalling is differentially inhibited by prolonged Glc and Gln deprivation. • Unlike Glc, Gln plays no major role in HIF signalling in chronically hypoxic cells.

  11. Hedgehog signaling contributes to basic fibroblast growth factor-regulated fibroblast migration

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Zhong Xin [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Sun, Cong Cong [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wenzhou People' s Hospital, Wenzhou, Zhejiang (China); Ting Zhu, Yu; Wang, Ying; Wang, Tao; Chi, Li Sha; Cai, Wan Hui [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zheng, Jia Yong [Wenzhou People' s Hospital, Wenzhou, Zhejiang (China); Zhou, Xuan [Ningbo First Hospital, Ningbo, Zhejiang (China); Cong, Wei Tao [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Xiao Kun, E-mail: proflxk@163.com [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Jin, Li Tai, E-mail: jin_litai@126.com [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China)

    2017-06-15

    Fibroblast migration is a central process in skin wound healing, which requires the coordination of several types of growth factors. bFGF, a well-known fibroblast growth factor (FGF), is able to accelerate fibroblast migration; however, the underlying mechanism of bFGF regulation fibroblast migration remains unclear. Through the RNA-seq analysis, we had identified that the hedgehog (Hh) canonical pathway genes including Smoothened (Smo) and Gli1, were regulated by bFGF. Further analysis revealed that activation of the Hh pathway via up-regulation of Smo promoted fibroblast migration, invasion, and skin wound healing, but which significantly reduced by GANT61, a selective antagonist of Gli1/Gli2. Western blot analyses and siRNA transfection assays demonstrated that Smo acted upstream of phosphoinositide 3-kinase (PI3K)-c-Jun N-terminal kinase (JNK)-β-catenin to promote cell migration. Moreover, RNA-seq and qRT-PCR analyses revealed that Hh pathway genes including Smo and Gli1 were under control of β-catenin, suggesting that β-catenin turn feedback activates Hh signaling. Taken together, our analyses identified a new bFGF-regulating mechanism by which Hh signaling regulates human fibroblast migration, and the data presented here opens a new avenue for the wound healing therapy. - Highlights: • bFGF regulates Hedgehog (Hh) signaling in fibroblasts. • The Smo and Gli two master regulators of Hh signaling positively regulate fibroblast migration. • Smo facilitates β-catenin nuclear translocation via activation PI3K/JNK/GSK3β. • β-catenin positively regulates fibroblast cell migration and the expression of Hh signaling genes including Smo and Gli.

  12. Origin and evolution of TNF and TNF receptor superfamilies

    Science.gov (United States)

    The tumor necrosis factor superfamily (TNFSF) and the TNF receptor superfamily (TNFRSF) have an ancient evolutionary origin that can be traced back to single copy genes within Arthropods. In humans, 18 TNFSF and 29 TNFRSF genes have been identified. Evolutionary models account for the increase in g...

  13. cAMP prevents TNF-induced apoptosis through inhibiting DISC complex formation in rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, Rajesh [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States); Xiang, Wenpei [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States); Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People' s Republic of China (China); Wang, Yinna [Vascular Medicine Institute, University of Pittsburgh School of Medicine, 10051-5A BST 3, 3501 Fifth Avenue, Pittsburgh, PA 15261 (United States); Zhang, Xiaoying [Department of Medicine/Endocrinology Division, University of Pittsburgh Medical Center, 200 Lothrop St., Pittsburgh, PA 15213 (United States); Billiar, Timothy R., E-mail: billiartr@upmc.edu [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer cAMP blocks cell death induced by TNF and actinomycin D in cultured hepatocytes. Black-Right-Pointing-Pointer cAMP blocks NF-{kappa}B activation induced by TNF and actinomycin D. Black-Right-Pointing-Pointer cAMP blocks DISC formation following TNF and actinomycin D exposure. Black-Right-Pointing-Pointer cAMP blocks TNF signaling at a proximal step. -- Abstract: Tumor necrosis factor {alpha} (TNF) is a pleiotropic proinflammatory cytokine that plays a role in immunity and the control of cell proliferation, cell differentiation, and apoptosis. The pleiotropic nature of TNF is due to the formation of different signaling complexes upon the binding of TNF to its receptor, TNF receptor type 1 (TNFR1). TNF induces apoptosis in various mammalian cells when the cells are co-treated with a transcription inhibitor like actinomycin D (ActD). When TNFR1 is activated, it recruits an adaptor protein, TNF receptor-associated protein with death domain (TRADD), through its cytoplasmic death effector domain (DED). TRADD, in turn, recruits other signaling proteins, including TNF receptor-associated protein 2 (TRAF2) and receptor-associated protein kinase (RIPK) 1, to form a complex. Subsequently, this complex combines with FADD and procaspase-8, converts into a death-inducing signaling complex (DISC) to induce apoptosis. Cyclic AMP (cAMP) is a second messenger that regulates various cellular processes such as cell proliferation, gene expression, and apoptosis. cAMP analogues are reported to act as anti-apoptotic agents in various cell types, including hepatocytes. We found that a cAMP analogue, dibutyryl cAMP (db-cAMP), inhibits TNF + ActD-induced apoptosis in rat hepatocytes. The protein kinase A (PKA) inhibitor KT-5720 reverses this inhibitory effect of cAMP on apoptosis. Cytoprotection by cAMP involves down-regulation of various apoptotic signal regulators like TRADD and FADD and inhibition of caspase-8 and caspase-3 cleavage. We also found

  14. The PPARα - FGF21 hormone axis contributes to metabolic regulation by the hepatic JNK signaling pathway

    Science.gov (United States)

    Vernia, Santiago; Cavanagh-Kyros, Julie; Garcia-Haro, Luisa; Sabio, Guadalupe; Barrett, Tamera; Jung, Dae Young; Kim, Jason K.; Xu, Jia; Shulha, Hennady P.; Garber, Manuel; Gao, Guangping; Davis, Roger J.

    2014-01-01

    The cJun NH2-terminal kinase (JNK) stress signaling pathway is implicated in the metabolic response to the consumption of a high fat diet, including the development of obesity and insulin resistance. These metabolic adaptations involve altered liver function. Here we demonstrate that hepatic JNK potently represses the nuclear hormone receptor peroxisome proliferator-activated receptor α (PPARα). JNK therefore causes decreased expression of PPARα target genes that increase fatty acid oxidation / ketogenesis and promote the development of insulin resistance. We show that the PPARα target gene fibroblast growth factor 21 (Fgf21) plays a key role in this response because disruption of the hepatic PPARα - FGF21 hormone axis suppresses the metabolic effects of JNK-deficiency. This analysis identifies the hepatokine FGF21 as a critical mediator of JNK signaling in the liver. PMID:25043817

  15. Contribution of the polarization moments of different rank to the integral CPT signal

    Science.gov (United States)

    Taskova, E.; Alipieva, E.; Todorov, G.

    2016-01-01

    In the present work we investigate the relation of the polarization moments having different ranks with the tensor components which form the observable integral CPT signal, in the presence of a stray magnetic field. A numerical experiment with parameters close to the real ones is performed, using a program based on the irreducible tensor operator formalism1. The integral fluorescent signal is calculated for the non-polarized fluorescence at different laser power excitation. Detailed analysis of the numerical solutions for all tensor components which describe population and alignment allows visualizing the dynamics of their behavior in dependence on the experimental geometry and laboratory magnetic field B'. The dependence of population f00, longitudinal f02 and transverse f22 alignment in the presence of transverse magnetic field is investigated. The shape and sign of the resonance change with laser power.

  16. Immobilization contributes to exaggerated neuropeptide signaling, inflammatory changes, and nociceptive sensitization after fracture in rats.

    Science.gov (United States)

    Guo, Tian-Zhi; Wei, Tzuping; Li, Wen-Wu; Li, Xiang-Qi; Clark, J David; Kingery, Wade S

    2014-10-01

    A tibia fracture cast immobilized for 4 weeks can induce exaggerated substance P and calcitonin gene-related peptide signaling and neuropeptide-dependent nociceptive and inflammatory changes in the hind limbs of rats similar to those seen in complex regional pain syndrome (CRPS). Four weeks of hind limb cast immobilization can also induce nociceptive and vascular changes resembling CRPS. To test our hypothesis that immobilization alone could cause exaggerated neuropeptide signaling and inflammatory changes, we tested 5 cohorts of rats: 1) controls; 2) tibia fracture and hind limb casted; 3) hind limb casted, no fracture; 4) tibia fracture with intramedullary pinning, no cast; and 5) tibia fracture with intramedullary pinning and hind limb casting. After 4 weeks, the casts were removed and hind limb allodynia, unweighting, warmth, edema, sciatic nerve neuropeptide content, cutaneous and spinal cord inflammatory mediator levels, and spinal c-Fos activation were measured. After fracture with casting, there was allodynia, unweighting, warmth, edema, increased sciatic nerve substance P and calcitonin gene-related peptide, increased skin neurokinin 1 receptors and keratinocyte proliferation, increased inflammatory mediator expression in the hind paw skin (tumor necrosis factor-α, interleukin [IL]-1β, IL-6, nerve growth factor) and cord (IL-1β, nerve growth factor), and increased spinal c-Fos activation. These same changes were observed after cast immobilization alone, except that spinal IL-1β levels were not increased. Treating cast-only rats with a neurokinin 1 receptor antagonist inhibited development of nociceptive and inflammatory changes. Four weeks after fracture with pinning, all nociceptive and vascular changes had resolved and there were no increases in neuropeptide signaling or inflammatory mediator expression. Collectively, these data indicate that immobilization alone increased neuropeptide signaling and caused nociceptive and inflammatory changes similar

  17. Attenuated GABAergic Signaling in Intestinal Epithelium Contributes to Pathogenesis of Ulcerative Colitis.

    Science.gov (United States)

    Aggarwal, Surbhi; Ahuja, Vineet; Paul, Jaishree

    2017-10-01

    Neuromediators produced by enteric nervous system regulate inflammatory processes via interacting with enteric immune system. Role of γ-aminobutyric acid (GABA), which is also a neuromediator, has been implicated in autoimmune diseases like multiple sclerosis, type 1 diabetes, and rheumatoid arthritis, where they modulate the immune responses. However, its role in ulcerative colitis (UC) has not been defined. This study was carried out to investigate the role of GABA and its signaling components in pathogenesis of UC. Peripheral blood, colon mucosal biopsy, and fecal specimens were collected from UC and control groups. Quantification of GABA was done using ELISA. Expression of GABAergic signal system components was analyzed through RT-PCR analysis. Enumeration of GABA-producing bacteria was done by qPCR analysis. Activity of p38 MAPK and expression of proinflammatory cytokines were determined by immunohistochemistry and RT-PCR analysis, respectively. GABA levels were significantly reduced in patients with UC as compared to control group when measured in serum and colon biopsy. Altered expression of GABAergic signal system was observed in UC patients. Reduced abundance of selected GABA-producing bacteria was detected in stool samples of UC patients as compared to control. p38 MAPK activity and expression of its downstream effector cytokines were found to be increased in UC patients as compared to control. Reduced levels of GABA were observed in patients with UC, and this leads to hyperactivation of p38 MAPK and overexpression of downstream effector cytokines suggesting a role of GABA in pathogenesis of UC.

  18. The Contribution of Knowledge about Anaphors, Organisational Signals and Refutations to Reading Comprehension

    Science.gov (United States)

    García, J. Ricardo; Bustos, Andrea; Sánchez, Emilio

    2015-01-01

    Expository texts contain rhetorical devices that help readers to connect text ideas (within a text and with prior knowledge) and to monitor reading. Rhetorical competence addresses readers' skill in detecting, understanding and using these devices. We examined the contribution of rhetorical competence to reading comprehension on two groups of 11-…

  19. Macrophages activate iNOS signaling in adventitial fibroblasts and contribute to adventitia fibrosis.

    Science.gov (United States)

    Zhang, Guannan; Li, Xiaodong; Sheng, Chengyu; Chen, Xiaohui; Chen, Yu; Zhu, Dingliang; Gao, Pingjin

    2016-12-30

    A large amount of NO is generated through the inducible nitric oxide synthase (iNOS) pathway from the vascular adventitia in various vascular diseases. However, it is currently not fully understood how the iNOS signaling pathway is activated. In the present study, this question was addressed in the context of adventitial cellular interactions. A rat model of acute hypertension in the contralateral carotid arteries was established through transverse aortic constriction (TAC) surgery. In this model, activated macrophages were found surrounded by a large quantity of iNOS-expressing adventitial fibroblasts (AFs), suggesting a possible causal relationship between macrophages and iNOS activation of the neighboring AFs. In an in vitro model, a macrophage-like cell line RAW 264.7 was first activated by LPS treatment. The supernatant was then harvested and applied to treat primary rat AFs. iNOS in AFs was activated robustly by the supernatant treatment but not by LPS itself. Treating AFs with interleukin-1β (IL-1β) also activated iNOS signaling, suggesting that the IL-1β pathway might be a possible mediator. As a consequence of the iNOS activation, total protein nitration and S-nitrosylation significantly increased in those AFs. Additionally, increased deposition of type I and type III collagens was observed in both in vitro and in vivo models. The collagen deposition was partially restored by an iNOS inhibitor, 1400 W. These findings highlight the importance of iNOS signaling during vascular inflammation, and advance our understanding of its activation through a cellular interaction perspective. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Evidence for a Contribution of ALA Synthesis to Plastid-To-Nucleus Signalling

    Directory of Open Access Journals (Sweden)

    Olaf eCzarnecki

    2012-10-01

    Full Text Available The formation of 5-aminolevulinic acid (ALA in tetrapyrrole biosynthesis is widely controlled by environmental and metabolic feedback cues that determine the influx into the entire metabolic path. Because of its central role as the rate-limiting step, we hypothesised a potential role of ALA biosynthesis in tetrapyrrole-mediated retrograde signalling and exploited the direct impact of ALA biosynthesis on nuclear gene expression (NGE by using two different approaches. Firstly, the Arabidopsis gun1, hy1 (gun2, hy2 (gun3, gun4 mutants showing uncoupled NGE from the physiological state of chloroplasts were thoroughly examined for regulatory modifications of ALA synthesis and transcriptional control in the nucleus. We found that reduced ALA-synthesising capacity is common to analysed gun mutants. Inhibition of ALA synthesis by gabaculine (GAB that inactivates glutamate-1-semialdhyde aminotransferase and ALA feeding of wild-type and mutant seedlings corroborate the expression data of gun mutants. Transcript level of photosynthetic marker genes were enhanced in norflurazon (NF-treated seedlings upon additional GAB treatment, while enhanced ALA amounts diminish these RNA levels in NF-treated wild-type in comparison to the solely NF-treated seedlings. Secondly, the impact of posttranslationally down-regulated ALA synthesis on NGE was investigated by global transcriptome analysis of GAB-treated Arabidopsis seedlings and the gun4-1 mutant, which is also characterized by reduced ALA formation. A common set of significantly modulated genes was identified indicating ALA synthesis as a potential signal emitter. The overrepresented gene ontology categories of genes with decreased or increased transcript abundance highlight a few biological processes and cellular functions, which are remarkably affected in response to plastid-localised ALA biosynthesis. These results support the hypothesis that ALA biosynthesis correlates with retrograde signalling

  1. Warning signals are seductive: relative contributions of color and pattern to predator avoidance and mate attraction in Heliconius butterflies.

    Science.gov (United States)

    Finkbeiner, Susan D; Briscoe, Adriana D; Reed, Robert D

    2014-12-01

    Visual signaling in animals can serve many uses, including predator deterrence and mate attraction. In many cases, signals used to advertise unprofitability to predators are also used for intraspecific communication. Although aposematism and mate choice are significant forces driving the evolution of many animal phenotypes, the interplay between relevant visual signals remains little explored. Here, we address this question in the aposematic passion-vine butterfly Heliconius erato by using color- and pattern-manipulated models to test the contributions of different visual features to both mate choice and warning coloration. We found that the relative effectiveness of a model at escaping predation was correlated with its effectiveness at inducing mating behavior, and in both cases wing color was more predictive of presumptive fitness benefits than wing pattern. Overall, however, a combination of the natural (local) color and pattern was most successful for both predator deterrence and mate attraction. By exploring the relative contributions of color versus pattern composition in predation and mate preference studies, we have shown how both natural and sexual selection may work in parallel to drive the evolution of specific animal color patterns. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  2. Contributions of AMPK and p53 dependent signaling to radiation response in the presence of metformin.

    Science.gov (United States)

    Muaddi, Hala; Chowdhury, Sanjana; Vellanki, Ravi; Zamiara, Paul; Koritzinsky, Marianne

    2013-09-01

    Metformin is commonly prescribed to treat type 2 diabetes, and has additional potential as a cancer prophylactic and therapeutic. Metformin activates AMPK that in turn can launch a p53-dependent metabolic checkpoint. Possible interactions between metformin and radiation are poorly understood. Since radiation-induced signaling also involves AMPK and p53, we investigated their importance in mediating responses to metformin and radiation. A549 cells, HCT116 cells wildtype or knockout for p53 or MEFs wildtype or double knockout for AMPKα1 and α2 were irradiated in the presence or absence of metformin. The impact of metformin on oxygen consumption and proliferation rates was determined, as well as clonogenic radiation survival. Metformin resulted in moderate radiation protection in all cell lines, irrespective of AMPK and p53. Loss of AMPK sensitized cells to the anti-proliferative effects of metformin, while loss of p53 promoted both the growth inhibitory and toxic effects of metformin. Consequently, overall cell death after radiation was similar with and without metformin irrespective of AMPK or p53 genotype. The anti-proliferative activity of metformin may confer benefit in combination with radiotherapy, and this benefit is intensified upon loss of AMPK or p53 signaling. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  3. Covert Verb Reading Contributes to Signal Classification of Motor Imagery in BCI.

    Science.gov (United States)

    Zhang, Hong; Sun, Yaoru; Li, Jie; Wang, Fang; Wang, Zijian

    2018-01-01

    Motor imagery is widely used in the brain-computer interface (BCI) systems that can help people actively control devices to directly communicate with the external world, but its training and performance effect is usually poor for normal people. To improve operators' BCI performances, here we proposed a novel paradigm, which combined the covert verb reading in the traditional motor imagery paradigm. In our proposed paradigm, participants were asked to covertly read the presented verbs during imagining right hand or foot movements referred by those verbs. EEG signals were recorded with both our proposed paradigm and the traditional paradigm. By the common spatial pattern method, we, respectively, decomposed these signals into spatial patterns and extracted their features used in the following classification of support vector machine. Compared with the traditional paradigm, our proposed paradigm could generate clearer spatial patterns following a somatotopic distribution, which led to more distinguishable features and higher classification accuracies than those in the traditional paradigm. These results suggested that semantic processing of verbs can influence the brain activity of motor imagery and enhance the mu event-related desynchronisation. The combination of semantic processing with motor imagery is therefore a promising method for the improvement of operators' BCI performances.

  4. Physiological contribution of P2X receptors in postreceptoral signal processing in the mouse retina.

    Science.gov (United States)

    Ichinohe, Sho; Ishii, Toshiyuki; Takahashi, Hiroshi; Kaneda, Makoto

    2017-02-01

    ATP activates P2X receptors and acts as a neurotransmitter in the nervous system. We have previously reported that P2X receptors modulate the firing rate of retinal ganglion cells. Since many subtypes of P2X receptors are distributed in the mouse retina, it is likely that the modulatory effects of P2X receptor-mediated signaling can occur at multiple synaptic levels in the retina. In this study, we investigated whether P2X receptors expressed between the photoreceptor layer and the inner nuclear layer in the mouse retina were physiologically functional, by electroretinography (ERG). In the combined rod-cone ERG and the scotopic ERG, intravitreal injection of PPADS, an antagonist of P2X receptors, had no effects on the amplitude of the a-wave, but decreased the amplitude of the b-wave. In the photopic ERG, intravitreal injection of PPADS significantly decreased the amplitude of both the a-wave and the b-wave. In ex vivo recordings, a decrease in the b-wave amplitude was observed at 20μM PPADS, confirming that the inhibition of the b-wave by intravitreal injection of PPADS is due to the inhibition of P2X receptors. Our findings suggest that P2X receptor-mediated signaling has a physiological effect in both the rod and the cone pathways in postreceptoral processing. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

  5. Low Expression of CAPON in Glioma Contributes to Cell Proliferation via the Akt Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Shangfeng Gao

    2016-11-01

    Full Text Available CAPON is an adapter protein for nitric oxide synthase 1 (NOS1. CAPON has two isoforms in the human brain: CAPON-L (long form of CAPON and CAPON-S (short form of CAPON. Recent studies have indicated the involvement of CAPON in tumorigenesis beyond its classical role in NOS1 activity regulation. In this study, we found that the protein levels of CAPON-S, but not than CAPON-L, were significantly decreased in glioma tissues. Therefore, we established lentivirus-mediated stable cell lines with CAPON-S overexpression or down-regulation, and investigated the role of CAPON-S in the proliferation of glioma cells by using CCK8, EdU, and flow cytometry assays. Overexpression of CAPON-S reduced the cell variability and the percentage of EdU-positive cells, and arrested the cells in the G1 phase in glioma cells. Silencing of CAPON by short-hairpin RNA showed the opposite effects. Furthermore, an intracellular signaling array revealed that overexpression of CAPON-S resulted in a remarkable reduction in the phosphorylation of Akt and S6 ribosomal protein in glioma cells, which was further confirmed by Western blot. These findings suggest that CAPON may function as a tumor suppressor in human brain glioma and that the inactivation of the Akt signaling pathway caused by CAPON-S overexpression may provide insight into the underlying mechanism of CAPON in glioma cell proliferation.

  6. Absence of TNF-α enhances inflammatory response in the newborn lung undergoing mechanical ventilation.

    Science.gov (United States)

    Ehrhardt, Harald; Pritzke, Tina; Oak, Prajakta; Kossert, Melina; Biebach, Luisa; Förster, Kai; Koschlig, Markus; Alvira, Cristina M; Hilgendorff, Anne

    2016-05-15

    Bronchopulmonary dysplasia (BPD), characterized by impaired alveolarization and vascularization in association with lung inflammation and apoptosis, often occurs after mechanical ventilation with oxygen-rich gas (MV-O2). As heightened expression of the proinflammatory cytokine TNF-α has been described in infants with BPD, we hypothesized that absence of TNF-α would reduce pulmonary inflammation, and attenuate structural changes in newborn mice undergoing MV-O2 Neonatal TNF-α null (TNF-α(-/-)) and wild type (TNF-α(+/+)) mice received MV-O2 for 8 h; controls spontaneously breathed 40% O2 Histologic, mRNA, and protein analysis in vivo were complemented by in vitro studies subjecting primary pulmonary myofibroblasts to mechanical stretch. Finally, TNF-α level in tracheal aspirates from preterm infants were determined by ELISA. Although MV-O2 induced larger and fewer alveoli in both, TNF-α(-/-) and TNF-α(+/+) mice, it caused enhanced lung apoptosis (TUNEL, caspase-3/-6/-8), infiltration of macrophages and neutrophils, and proinflammatory mediator expression (IL-1β, CXCL-1, MCP-1) in TNF-α(-/-) mice. These differences were associated with increased pulmonary transforming growth factor-β (TGF-β) signaling, decreased TGF-β inhibitor SMAD-7 expression, and reduced pulmonary NF-κB activity in ventilated TNF-α(-/-) mice. Preterm infants who went on to develop BPD showed significantly lower TNF-α levels at birth. Our results suggest a critical balance between TNF-α and TGF-β signaling in the developing lung, and underscore the critical importance of these key pathways in the pathogenesis of BPD. Future treatment strategies need to weigh the potential benefits of inhibiting pathologic cytokine expression against the potential of altering key developmental pathways. Copyright © 2016 the American Physiological Society.

  7. Anti-TNF-α antibody alleviates insulin resistance in rats with sepsis-induced stress hyperglycemia.

    Science.gov (United States)

    Qu, W; Han, C; Li, M; Zhang, J; Jiang, Z

    2017-10-13

    To explore the effects and mechanisms of anti-tumor necrosis factor-α (TNF-α) antibody on insulin resistance (IR) in rats with sepsis-induced stress hyperglycemia. The sepsis-induced stress hyperglycemic rat model was constructed by cecal ligation and puncture combined with the intraperitoneal injection of lipopolysaccharide. The rats were randomly divided into six groups: normal control (NC) group, surgical rats (Cntl) group, high-dose anti-TNF-α antibody therapy (TNF, 6 mg/kg) group, low-dose anti-TNF-α antibody therapy (Tnf, 3 mg/kg) group, insulin therapy (INS) group, and INS + Tnf group. The blood glucose and serum insulin concentrations were detected, followed by analysis of intraperitoneal glucose tolerance test (IPGTT) and hyperinsulinemic-euglycemic clamp. Finally, the expression levels of phospho-Akt (p-Akt), Akt, p-mTOR, mTOR, nuclear factor-κB (NFκB), I kappa beta kinase (IKKβ), and suppressor of cytokine signaling (SOCS-3) were detected by western blotting. There was no significant difference in blood glucose concentrations among these groups, while the serum insulin concentration in TNF and Tnf groups was lower than that in the Cntl group at postoperative 6 h (P TNF group than that in the Cntl group (P Tnf and TNF groups (P TNF-α antibody could reduce IR by inhibiting AKt/mTOR signaling pathway and the expression levels of NFκB, IKKβ, and SOCS-3 in rats with sepsis-induced stress hyperglycemia.

  8. AA/12-lipoxygenase signaling contributes to inhibitory learning in Hermissenda Type B photoreceptors

    Directory of Open Access Journals (Sweden)

    Tony L Walker

    2010-08-01

    Full Text Available Conditioned inhibition (CI is a major category of associative learning that occurs when an organism learns that one stimulus predicts the absence of another. In addition to being important in its own right, CI is interesting because its occurrence implies that the organism has formed an association between stimuli that are non-coincident. In contrast to other categories of associative learning that are dependent upon temporal contiguity (pairings of stimuli, the neurobiology of CI is virtually unexplored. We have previously described a simple form of CI learning in Hermissenda, whereby animals’ phototactic behavior is increased by repeated exposures to explicitly unpaired (EU presentations of light and rotation. EU conditioning also produces characteristic reductions in the excitability and light response, and increases several somatic K+ currents in Type B photoreceptors. Type B photoreceptors are a major site of plasticity for classical conditioning in Hermissenda. Because arachidonic acid (AA and/or its metabolites open diverse K+ channels in many cell types, we examined the potential contribution of AA to CI. Our results indicate that AA contributes to one of the major effects of EU-conditioning on Type B photoreceptors: decreases in light-evoked spike activity. We find that AA increases the transient (IA somatic K+ current in Type B photoreceptors, further mimicking CI training. In addition, our results indicate that metabolism of AA by a 12-lipoxygenase enzyme is critical for these effects of AA, and further that 12-lipoxygenase metabolites are apparently generated during CI training.

  9. Local TNF causes NFATc1-dependent cholesterol-mediated podocyte injury

    Science.gov (United States)

    Pedigo, Christopher E.; Ducasa, Gloria Michelle; Leclercq, Farah; Sloan, Alexis; Hashmi, Tahreem; Molina-David, Judith; Ge, Mengyuan; Lassenius, Mariann I.; Groop, Per-Henrik; Kretzler, Matthias; Martini, Sebastian; Reich, Heather; Wahl, Patricia; Ghiggeri, GianMarco; Burke, George W.; Kretz, Oliver; Huber, Tobias B.; Mendez, Armando J.; Merscher, Sandra

    2016-01-01

    High levels of circulating TNF and its receptors, TNFR1 and TNFR2, predict the progression of diabetic kidney disease (DKD), but their contribution to organ damage in DKD remains largely unknown. Here, we investigated the function of local and systemic TNF in podocyte injury. We cultured human podocytes with sera collected from DKD patients, who displayed elevated TNF levels, and focal segmental glomerulosclerosis (FSGS) patients, whose TNF levels resembled those of healthy patients. Exogenous TNF administration or local TNF expression was equally sufficient to cause free cholesterol–dependent apoptosis in podocytes by acting through a dual mechanism that required a reduction in ATP-binding cassette transporter A1–mediated (ABCA1-mediated) cholesterol efflux and reduced cholesterol esterification by sterol-O-acyltransferase 1 (SOAT1). TNF-induced albuminuria was aggravated in mice with podocyte-specific ABCA1 deficiency and was partially prevented by cholesterol depletion with cyclodextrin. TNF-stimulated free cholesterol–dependent apoptosis in podocytes was mediated by nuclear factor of activated T cells 1 (NFATc1). ABCA1 overexpression or cholesterol depletion was sufficient to reduce albuminuria in mice with podocyte-specific NFATc1 activation. Our data implicate an NFATc1/ABCA1-dependent mechanism in which local TNF is sufficient to cause free cholesterol–dependent podocyte injury irrespective of TNF, TNFR1, or TNFR2 serum levels. PMID:27482889

  10. Neurodegenerative and neuroprotective effects of tumor necrosis factor (TNF) in retinal ischemia : Opposite roles of TNF receptor 1 and TNF receptor 2

    NARCIS (Netherlands)

    Fontaine, Sharon; Mohand-Said, S; Hanoteau, N; Fuchs, L; Pfizenmaier, K; Eisel, U

    2002-01-01

    Tumor necrosis factor (TNF) is an important factor in various acute and chronic neurodegenerative disorders. In retinal ischemia, we show early, transient upregulation of TNF, TNF receptor 1 (TNF-R1), and TNF-R2 6 hr after reperfusion preceding neuronal cell loss. To assess the specific role of TNF

  11. Electrophysiological signals associated with fluency of different levels of processing reveal multiple contributions to recognition memory.

    Science.gov (United States)

    Li, Bingbing; Taylor, Jason R; Wang, Wei; Gao, Chuanji; Guo, Chunyan

    2017-08-01

    Processing fluency appears to influence recognition memory judgements, and the manipulation of fluency, if misattributed to an effect of prior exposure, can result in illusory memory. Although it is well established that fluency induced by masked repetition priming leads to increased familiarity, manipulations of conceptual fluency have produced conflicting results, variously affecting familiarity or recollection. Some recent studies have found that masked conceptual priming increases correct recollection (Taylor & Henson, 2012), and the magnitude of this behavioural effect correlates with analogous fMRI BOLD priming effects in brain regions associated with recollection (Taylor, Buratto, & Henson, 2013). However, the neural correlates and time-courses of masked repetition and conceptual priming were not compared directly in previous studies. The present study used event-related potentials (ERPs) to identify and compare the electrophysiological correlates of masked repetition and conceptual priming and investigate how they contribute to recognition memory. Behavioural results were consistent with previous studies: Repetition primes increased familiarity, whereas conceptual primes increased correct recollection. Masked repetition and conceptual priming also decreased the latency of late parietal component (LPC). Masked repetition priming was associated with an early P200 effect and a later parietal maximum N400 effect, whereas masked conceptual priming was only associated with a central-parietal maximum N400 effect. In addition, the topographic distributions of the N400 repetition priming and conceptual priming effects were different. These results suggest that fluency at different levels of processing is associated with different ERP components, and contributes differentially to subjective recognition memory experiences. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Cathelicidin rCRAMP stimulates rat mast cells to generate cysteinyl leukotrienes, synthesize TNF and migrate: involvement of PLC/A2, PI3K and MAPK signaling pathways.

    Science.gov (United States)

    Bąbolewska, Edyta; Pietrzak, Anna; Brzezińska-Błaszczyk, Ewa

    2014-11-01

    Cathelicidins represent a family of cationic peptides involved in host defense systems. Apart from exerting direct anti-microbial effects, cathelicidins can regulate immune responses by affecting the activity of cells playing a role in antibacterial defense. Taking into account that mast cells are critical components of host defense, the aim of this study was to determine whether rat cathelicidin-related anti-microbial peptide (rCRAMP) can influence mast cell activity. We have demonstrated that activation of fully mature rat mast cells with rCRAMP resulted in generation and release of cysteinyl leukotrienes (cysLTs). However, rCRAMP failed to induce mast cell degranulation and histamine release. We also found that rCRAMP stimulated rat mast cells to synthesize TNF, but not CXCL8. What is more, this peptide induced GM-CSF, IL-1β, CCL2 and CCL3 but not IL-33 mRNA expression in mast cells. Finally, we showed that this cathelicidin serves as potent chemoattractant for rat mast cells. rCRAMP-mediated cysLT synthesis and mast cell migration were strongly inhibited by IL-10 pre-treatment. With the use of specific inhibitors, we established that activation of PLC/A2 and ERK1/2, but not p38, was required for rCRAMP-induced mast cell stimulation, while PI3K-dependent pathway is involved in both TNF synthesis and mast cell migration. Our results suggest that cathelicidins can amplify inflammatory responses by causing mast cells accumulation and by stimulating these cells to release potent pro-inflammatory mediators. © The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Synergistic induction of CX3CL1 by TNF alpha and IFN gamma in osteoblasts from rheumatoid arthritis: involvement of NF-kappa B and STAT-1 signaling pathways

    Directory of Open Access Journals (Sweden)

    Kuninobu Wakabayashi

    2008-10-01

    Full Text Available Takeo Isozaki, Tsuyoshi Kasama, Ryo Takahashi, Tsuyoshi Odai, Kuninobu Wakabayashi, Hirohito Kanemitsu, Kyoko Nohtomi, Hiroko T Takeuchi, Satoshi Matsukura, Masakazu TezukaDivision of Rheumatology, Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan, and the Department of Orthopedics, Denencyofu Central Hospital, Tokyo, JapanAbstract: To explore the regulation of CX3CL1 in inflammatory bone diseases, CX3CL1 expression by osteoblasts (OB was examined. Human OB isolated from rheumatoid arthritis (RA patients, osteoarthritis patients, and normal individuals were incubated in the presence of cytokines. Soluble CX3CL1 levels were determined with an enzyme-linked immunosorbent assay. Expression of CX3CL1 mRNA was examined using quantitative real-time polymerase chain reaction. Although tumor necrosis factor (TNF-α or interferon (IFN-γ alone RA OB induced negligible CX3CL1 secretion, the combination of TNF-α and IFN-γ induced dramatic increases in both soluble CX3CL1 protein and mRNA transcripts. This synergistic effect was more pronounced in OB from RA than in OB from either osteoarthritis or normal individuals. The expression of CX3CL1 was markedly reduced by specific inhibitors of the nuclear factor-κB (NF-κB or STAT-1 transcription factor. These findings suggest that osteoblasts are an important cellular source of CX3CL1 and may play roles in inflammatory bone/joint diseases.Keywords: osteoblast, CX3CL1, chemokine, NF-κB, STAT-1

  14. The ethylene response factor Pti5 contributes to potato aphid resistance in tomato independent of ethylene signalling

    Science.gov (United States)

    Wu, Chengjun; Avila, Carlos A.; Goggin, Fiona L.

    2015-01-01

    Ethylene response factors (ERFs) comprise a large family of transcription factors that regulate numerous biological processes including growth, development, and response to environmental stresses. Here, we report that Pti5, an ERF in tomato [Solanum lycopersicum (Linnaeus)] was transcriptionally upregulated in response to the potato aphid Macrosiphum euphorbiae (Thomas), and contributed to plant defences that limited the population growth of this phloem-feeding insect. Virus-induced gene silencing of Pti5 enhanced aphid population growth on tomato, both on an aphid-susceptible cultivar and on a near-isogenic genotype that carried the Mi-1.2 resistance (R) gene. These results indicate that Pti5 contributes to basal resistance in susceptible plants and also can synergize with other R gene-mediated defences to limit aphid survival and reproduction. Although Pti5 contains the ERF motif, induction of this gene by aphids was independent of ethylene, since the ACC deaminase (ACD) transgene, which inhibits ethylene synthesis, did not diminish the responsiveness of Pti5 to aphid infestation. Furthermore, experiments with inhibitors of ethylene synthesis revealed that Pti5 and ethylene have distinctly different roles in plant responses to aphids. Whereas Pti5 contributed to antibiotic plant defences that limited aphid survival and reproduction on both resistant (Mi-1.2+) and susceptible (Mi-1.2–) genotypes, ethylene signalling promoted aphid infestation on susceptible plants but contributed to antixenotic defences that deterred the early stages of aphid host selection on resistant plants. These findings suggest that the antixenotic defences that inhibit aphid settling and the antibiotic defences that depress fecundity and promote mortality are regulated through different signalling pathways. PMID:25504643

  15. The ethylene response factor Pti5 contributes to potato aphid resistance in tomato independent of ethylene signalling.

    Science.gov (United States)

    Wu, Chengjun; Avila, Carlos A; Goggin, Fiona L

    2015-02-01

    Ethylene response factors (ERFs) comprise a large family of transcription factors that regulate numerous biological processes including growth, development, and response to environmental stresses. Here, we report that Pti5, an ERF in tomato [Solanum lycopersicum (Linnaeus)] was transcriptionally upregulated in response to the potato aphid Macrosiphum euphorbiae (Thomas), and contributed to plant defences that limited the population growth of this phloem-feeding insect. Virus-induced gene silencing of Pti5 enhanced aphid population growth on tomato, both on an aphid-susceptible cultivar and on a near-isogenic genotype that carried the Mi-1.2 resistance (R) gene. These results indicate that Pti5 contributes to basal resistance in susceptible plants and also can synergize with other R gene-mediated defences to limit aphid survival and reproduction. Although Pti5 contains the ERF motif, induction of this gene by aphids was independent of ethylene, since the ACC deaminase (ACD) transgene, which inhibits ethylene synthesis, did not diminish the responsiveness of Pti5 to aphid infestation. Furthermore, experiments with inhibitors of ethylene synthesis revealed that Pti5 and ethylene have distinctly different roles in plant responses to aphids. Whereas Pti5 contributed to antibiotic plant defences that limited aphid survival and reproduction on both resistant (Mi-1.2+) and susceptible (Mi-1.2-) genotypes, ethylene signalling promoted aphid infestation on susceptible plants but contributed to antixenotic defences that deterred the early stages of aphid host selection on resistant plants. These findings suggest that the antixenotic defences that inhibit aphid settling and the antibiotic defences that depress fecundity and promote mortality are regulated through different signalling pathways. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  16. The controversial role of TNF in melanoma

    DEFF Research Database (Denmark)

    Donia, Marco; Kjeldsen, Julie Westerlin; Svane, Inge Marie

    2016-01-01

    ABSTRACT: TNF has been associated with both inhibition and promotion of tumor growth. We recently described a mechanism by which tumor cells attract TNF producing cells via expression of MHC class II molecules.......ABSTRACT: TNF has been associated with both inhibition and promotion of tumor growth. We recently described a mechanism by which tumor cells attract TNF producing cells via expression of MHC class II molecules....

  17. Placental ischemia-induced increases in brain water content and cerebrovascular permeability: role of TNF

    Science.gov (United States)

    Warrington, Junie P.; Drummond, Heather A.; Granger, Joey P.

    2015-01-01

    Cerebrovascular complications and increased risk of encephalopathies are characteristic of preeclampsia and contribute to 40% of preeclampsia/eclampsia-related deaths. Circulating tumor necrosis factor-α (TNF-α) is elevated in preeclamptic women, and infusion of TNF-α into pregnant rats mimics characteristics of preeclampsia. While this suggests that TNF-α has a mechanistic role to promote preeclampsia, the impact of TNF-α on the cerebral vasculature during pregnancy remains unclear. We tested the hypothesis that TNFcontributes to cerebrovascular abnormalities during placental ischemia by first infusing TNF-α in pregnant rats (200 ng/day ip, from gestational day 14 to 19) at levels to mimic those reported in preeclamptic women. TNF-α increased mean arterial pressure (MAP, P cerebral edema by increasing BBB permeability and is an underlying factor in the development of cerebrovascular abnormalities associated with preeclampsia complicated by placental ischemia. PMID:26400187

  18. mRNA Decapping and 5′-3′ Decay Contribute to the Regulation of ABA Signaling in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Izabela Wawer

    2018-03-01

    Full Text Available Defects in RNA processing and degradation pathways often lead to developmental abnormalities, impaired hormonal signaling and altered resistance to abiotic and biotic stress. Here we report that components of the 5′-3′ mRNA decay pathway, DCP5, LSM1-7 and XRN4, contribute to a proper response to a key plant hormone abscisc acid (ABA, albeit in a different manner. Plants lacking DCP5 are more sensitive to ABA during germination, whereas lsm1a lsm1b and xrn4-5 mutants are affected at the early stages of vegetative growth. In addition, we show that DCP5 and LSM1 regulate mRNA stability and act in translational repression of the main components of the early ABA signaling, PYR/PYL ABA receptors and SnRK2s protein kinases. mRNA decapping DCP and LSM1-7 complexes also appear to modulate ABA-dependent expression of stress related transcription factors from the AP2/ERF/DREB family that in turn affect the level of genes regulated by the PYL/PYR/RCAR-PP2C-SnRK2 pathway. These observations suggest that ABA signaling through PYL/PYR/RCAR receptors and SnRK2s kinases is regulated directly and indirectly by the cytoplasmic mRNA decay pathway.

  19. Estrogen Signaling Contributes to Sex Differences in Macrophage Polarization during Asthma.

    Science.gov (United States)

    Keselman, Aleksander; Fang, Xi; White, Preston B; Heller, Nicola M

    2017-09-01

    Allergic asthma is a chronic Th2 inflammation in the lungs that constricts the airways and presents as coughing and wheezing. Asthma mostly affects boys in childhood and women in adulthood, suggesting that shifts in sex hormones alter the course of the disease. Alveolar macrophages have emerged as major mediators of allergic lung inflammation in animal models as well as humans. Whether sex differences exist in macrophage polarization and the molecular mechanism(s) that drive differential responses are not well understood. We found that IL-4-stimulated bone marrow-derived and alveolar macrophages from female mice exhibited greater expression of M2 genes in vitro and after allergen challenge in vivo. Alveolar macrophages from female mice exhibited greater expression of the IL-4Rα and estrogen receptor (ER) α compared with macrophages from male mice following allergen challenge. An ERα-specific agonist enhanced IL-4-induced M2 gene expression in macrophages from both sexes, but more so in macrophages from female mice. Furthermore, IL-4-stimulated macrophages from female mice exhibited more transcriptionally active histone modifications at M2 gene promoters than did macrophages from male mice. We found that supplementation of estrogen into ovariectomized female mice enhanced M2 polarization in vivo upon challenge with allergen and that macrophage-specific deletion of ERα impaired this M2 polarization. The effects of estrogen are long-lasting; bone marrow-derived macrophages from ovariectomized mice implanted with estrogen exhibited enhanced IL-4-induced M2 gene expression compared with macrophages from placebo-implanted littermates. Taken together, our findings suggest that estrogen enhances IL-4-induced M2 gene expression and thereby contributes to sex differences observed in asthma. Copyright © 2017 by The American Association of Immunologists, Inc.

  20. Evidence that TNF-β (lymphotoxin α) can activate the inflammatory environment in human chondrocytes

    Science.gov (United States)

    2013-01-01

    Introduction Inflammatory cytokines play a key role in the pathogenesis of joint diseases such as rheumatoid arthritis (RA). Current therapies target mainly tumor necrosis factor α (TNF-α) as this has proven benefits. However, a large number of patients do not respond to or become resistant to anti-TNF-α therapy. While the role of TNF-α in RA is quite evident, the role of TNF-β, also called lymphotoxin-α (LT-α), is unclear. In this study we investigated whether TNF-β and its receptor play a role in chondrocytes in the inflammatory environment. Methods An in vitro model of primary human chondrocytes was used to study TNF-β-mediated inflammatory signaling. Results Cytokine-induced inflammation enhances TNF-β and TNF-β-receptor expression in primary human chondrocytes accompanied by the up-regulation of inflammatory (cyclooxygenase-2), matrix degrading (matrix metalloproteinase-9 and -13) and apoptotic (p53, cleaved caspase-3) signaling pathways, all known to be regulated by NF-κB. In contrast, anti-TNF-β, similar to the natural NF-κB inhibitor (curcumin, diferuloylmethane) or the knockdown of NF-κB by using antisense oligonucleotides (ASO), suppressed IL-1β-induced NF-κB activation and its translocation to the nucleus, and abolished the pro-inflammatory and apoptotic effects of IL-1β. This highlights, at least in part, the crucial role of NF-κB in TNF-β-induced-inflammation in cartilage, similar to that expected for TNF-α. Finally, the adhesiveness between TNF-β-expressing T-lymphocytes and the responding chondrocytes was significantly enhanced through a TNF-β-induced inflammatory microenvironment. Conclusions These results suggest for the first time that TNF-β is involved in microenvironment inflammation in chondrocytes during RA parallel to TNF-α, resulting in the up-regulation of NF-κB signaling and activation of pro-inflammatory activity. PMID:24283517

  1. Nrf2 and NF-κB Signaling Pathways Contribute to Porphyra-334-Mediated Inhibition of UVA-Induced Inflammation in Skin Fibroblasts.

    Science.gov (United States)

    Ryu, Jina; Kwon, Mi-Jin; Nam, Taek-Jeong

    2015-07-31

    In this study, we examined the protective effects of porphyra-334 against UVA-irradiated cellular damage and elucidated the underlying mechanisms. Porphyra-334 prevented UVA-induced cell death and exhibited scavenging activities against intracellular oxidative stress induced by UVA irradiation in skin fibroblasts. We found that porphyra-334 significantly reduced the secretion and expression of IL-6 and TNF-α, reduced nuclear expression of Nuclear factor-κB (NF-κB), and sustained NF-E2-related factor 2 (Nrf2) activation. Further mechanism research revealed that porphyra-334 promoted the Nrf2 signaling pathway in UVA-irradiated skin fibroblasts. Our results show that the antioxidant effect of porphyra-334 is due to the direct scavenging of oxidative stress and its inhibitory effects on NF-κB-dependent inflammatory genes, such as IL-6 and TNF-κ. Therefore, we hypothesize that boosting the Nrf2- NF-κB-dependent response to counteract environmental stress is a promising strategy for the prevention of UVA-related damage.

  2. Nrf2 and NF-κB Signaling Pathways Contribute to Porphyra-334-Mediated Inhibition of UVA-Induced Inflammation in Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Jina Ryu

    2015-07-01

    Full Text Available In this study, we examined the protective effects of porphyra-334 against UVA-irradiated cellular damage and elucidated the underlying mechanisms. Porphyra-334 prevented UVA-induced cell death and exhibited scavenging activities against intracellular oxidative stress induced by UVA irradiation in skin fibroblasts. We found that porphyra-334 significantly reduced the secretion and expression of IL-6 and TNF-α, reduced nuclear expression of Nuclear factor-κB (NF-κB, and sustained NF-E2-related factor 2 (Nrf2 activation. Further mechanism research revealed that porphyra-334 promoted the Nrf2 signaling pathway in UVA-irradiated skin fibroblasts. Our results show that the antioxidant effect of porphyra-334 is due to the direct scavenging of oxidative stress and its inhibitory effects on NF-κB-dependent inflammatory genes, such as IL-6 and TNF-κ. Therefore, we hypothesize that boosting the Nrf2- NF-κB-dependent response to counteract environmental stress is a promising strategy for the prevention of UVA-related damage.

  3. Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF

    International Nuclear Information System (INIS)

    Tsukasaki, Masayuki; Yamada, Atsushi; Suzuki, Dai; Aizawa, Ryo; Miyazono, Agasa; Miyamoto, Yoichi; Suzawa, Tetsuo; Takami, Masamichi; Yoshimura, Kentaro; Morimura, Naoko; Yamamoto, Matsuo; Kamijo, Ryutaro

    2011-01-01

    Highlights: → TNF-α inhibits POEM gene expression. → Inhibition of POEM gene expression is caused by NF-κB activation by TNF-α. → Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-α. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-α (TNF-α), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-α-induced down-regulation of POEM gene expression occurred in both time- and dose-dependent manners through the nuclear factor kappa B (NF-κB) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-α in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-α-induced inhibition of osteoblast differentiation. These results suggest that TNF-α inhibits POEM expression through the NF-κB signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-α.

  4. NO and H2O2 contribute to SO2 toxicity via Ca2+ signaling in Vicia faba guard cells.

    Science.gov (United States)

    Yi, Min; Bai, Heli; Xue, Meizhao; Yi, Huilan

    2017-04-01

    NO and H 2 O 2 have been implicated as important signals in biotic and abiotic stress responses of plants to the environment. Previously, we have shown that SO 2 exposure increased the levels of NO and H 2 O 2 in plant cells. We hypothesize that, as signaling molecules, NO and H 2 O 2 mediate SO 2 -caused toxicity. In this paper, we show that SO 2 hydrates caused guard cell death in a concentration-dependent manner in the concentration range of 0.25 to 6 mmol L -1 , which was associated with elevation of intracellular NO, H 2 O 2 , and Ca 2+ levels in Vicia faba guard cells. NO donor SNP enhanced SO 2 toxicity, while NO scavenger c-PTIO and NO synthesis inhibitors L-NAME and tungstate significantly prevented SO 2 toxicity. ROS scavenger ascorbic acid (AsA) and catalase (CAT), Ca 2+ chelating agent EGTA, and Ca 2+ channel inhibitor LaCl 3 also markedly blocked SO 2 toxicity. In addition, both c-PTIO and AsA could completely block SO 2 -induced elevation of intracellular Ca 2+ level. Moreover, c-PTIO efficiently blocked SO 2 -induced H 2 O 2 elevation, and AsA significantly blocked SO 2 -induced NO elevation. These results indicate that extra NO and H 2 O 2 are produced and accumulated in SO 2 -treated guard cells, which further activate Ca 2+ signaling to mediate SO 2 toxicity. Our findings suggest that both NO and H 2 O 2 contribute to SO 2 toxicity via Ca 2+ signaling.

  5. ARG1 and ARL2 contribute to gravity signal transduction in the statocytes of Arabidopsis thaliana roots and hypocotyls

    Science.gov (United States)

    Masson, Patrick; Harrison, Benjamin; Stanga, John; Otegui, Marisa; Sedbrook, John

    those of the single mutants. We used this observation to design a genetic screen for the identification of new loci that contribute to the pgm gravity-signaling pathway. Two genetic enhancers of arg1-2 were identified this way, called mar1-1 and mar2-1. These mutations were shown to affect components of the protein-import complex found in the outer membrane of plastids. Interestingly, the columellar amyloplasts of arg1-2 mar2-1 mutant roots display wild-type ultra-structure, accumulate starch and sediment at wild-type rates upon gravistimulation. We conclude that the plastid outer envelope may contribute directly to gravity signal transduction within the statocytes.

  6. Association of TNF promoter polymorphisms with type 1 diabetes in the South Croatian population

    Directory of Open Access Journals (Sweden)

    VESNA BORASKA

    2008-01-01

    Full Text Available Type 1 diabetes mellitus (TIDM is an autoimmune disease characterized by the destruction of pancreatic p cells. Tumor necrosis factor (TNF is a pleotropic cytokine with potent immunomodulatory and inflammatory activity. Association studies of TNF polymorphisms and type 1 diabetes (TIDM frequently demonstrated TNF involvement with TIDM. Although TNF may play an important role in the pathogenesis of TIDM, the genetic association of TNF región with the disease has not been conclusive because of the strong linkage disequilibrium with HLA genes. In this study, we examined two TNF promoter variants (rs 1800629 at position -308, and rs361525 at position -238 for TIDM association in 233 patients and 144 controls from the population of South Croatia. A higher frequency of TNF -308 A alíele and also, a more frequent specific -308A -238G haplotype in TIDM patients were observed with a limited significance. However, we did not find strong evidence of association of TNF promoter polymorphisms with TIDM. In order to elucidate the trae contribution of TNF to TIDM susceptibility in our population, more comprehensive studies with HLA adjustment in a larger sample are required.

  7. The DYX2 locus and neurochemical signaling genes contribute to speech sound disorder and related neurocognitive domains.

    Science.gov (United States)

    Eicher, J D; Stein, C M; Deng, F; Ciesla, A A; Powers, N R; Boada, R; Smith, S D; Pennington, B F; Iyengar, S K; Lewis, B A; Gruen, J R

    2015-04-01

    A major milestone of child development is the acquisition and use of speech and language. Communication disorders, including speech sound disorder (SSD), can impair a child's academic, social and behavioral development. Speech sound disorder is a complex, polygenic trait with a substantial genetic component. However, specific genes that contribute to SSD remain largely unknown. To identify associated genes, we assessed the association of the DYX2 dyslexia risk locus and markers in neurochemical signaling genes (e.g., nicotinic and dopaminergic) with SSD and related endophenotypes. We first performed separate primary associations in two independent samples - Cleveland SSD (210 affected and 257 unaffected individuals in 127 families) and Denver SSD (113 affected individuals and 106 unaffected individuals in 85 families) - and then combined results by meta-analysis. DYX2 markers, specifically those in the 3' untranslated region of DCDC2 (P = 1.43 × 10(-4) ), showed the strongest associations with phonological awareness. We also observed suggestive associations of dopaminergic-related genes ANKK1 (P = 1.02 × 10(-2) ) and DRD2 (P = 9.22 × 10(-3) ) and nicotinic-related genes CHRNA3 (P = 2.51 × 10(-3) ) and BDNF (P = 8.14 × 10(-3) ) with case-control status and articulation. Our results further implicate variation in putative regulatory regions in the DYX2 locus, particularly in DCDC2, influencing language and cognitive traits. The results also support previous studies implicating variation in dopaminergic and nicotinic neural signaling influencing human communication and cognitive development. Our findings expand the literature showing genetic factors (e.g., DYX2) contributing to multiple related, yet distinct neurocognitive domains (e.g., dyslexia, language impairment, and SSD). How these factors interactively yield different neurocognitive and language-related outcomes remains to be elucidated. © 2015 The Authors. Genes, Brain and Behavior published by

  8. Microbial patterns signaling via Toll-like receptors 2 and 5 contribute to epithelial repair, growth and survival.

    Directory of Open Access Journals (Sweden)

    Renat Shaykhiev

    Full Text Available Epithelial cells (ECs continuously interact with microorganisms and detect their presence via different pattern-recognition receptors (PRRs including Toll-like receptors (TLRs. Ligation of epithelial TLRs by pathogens is usually associated with the induction of pro-inflammatory mediators and antimicrobial factors. In this study, using human airway ECs as a model, we found that detection of microbial patterns via epithelial TLRs directly regulates tissue homeostasis. Staphylococcus aureus (S. aureus and microbial patterns signaling via TLR2 and TLR5 induce a set of non-immune epithelial responses including cell migration, wound repair, proliferation, and survival of primary and cancerous ECs. Using small interfering RNA (siRNA gene targeting, receptor-tyrosine kinase microarray and inhibition studies, we determined that TLR and the epidermal growth factor receptor (EGFR mediate the stimulating effect of microbial patterns on epithelial repair. Microbial patterns signaling via Toll-like receptors 2 and 5 contribute to epithelial repair, growth and survival. This effect is independent of hematopoietic and other cells as well as inflammatory cytokines suggesting that epithelia are able to regulate their integrity in an autonomous non-inflammatory manner by sensing microbes directly via TLRs.

  9. Increased concentrations of tumour necrosis factor (TNF) and soluble TNF receptors in biliary obstruction in mice; soluble TNF receptors as prognostic factors for mortality

    NARCIS (Netherlands)

    Bemelmans, M. H.; Greve, J. W.; Gouma, D. J.; Buurman, W. A.

    1996-01-01

    Systemic tumour necrosis factor (TNF) is present in jaundiced mice. Two soluble TNF receptors, sTNFr-P55 and sTNFr-P75 are reported to play a part in the natural defence against TNF. This study investigated the properties of circulating TNF and sTNFr in jaundiced mice. The data show that TNF in

  10. Abnormal Cell Responses and Role of TNF-α in Impaired Diabetic Wound Healing

    Science.gov (United States)

    Xu, Fanxing; Zhang, Chenying; Graves, Dana T.

    2013-01-01

    Impaired diabetic wound healing constitutes a major health problem. The impaired healing is caused by complex factors such as abnormal keratinocyte and fibroblast migration, proliferation, differentiation, and apoptosis, abnormal macrophage polarization, impaired recruitment of mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs), and decreased vascularization. Diabetes-enhanced and prolonged expression of TNF-α also contributes to impaired healing. In this paper, we discuss the abnormal cell responses in diabetic wound healing and the contribution of TNF-α. PMID:23484152

  11. Tristetraprolin mediates radiation-induced TNF-α production in lung macrophages.

    Directory of Open Access Journals (Sweden)

    Dipankar Ray

    Full Text Available The efficacy of radiation therapy for lung cancer is limited by radiation-induced lung toxicity (RILT. Although tumor necrosis factor-alpha (TNFsignaling plays a critical role in RILT, the molecular regulators of radiation-induced TNF-α production remain unknown. We investigated the role of a major TNF-α regulator, Tristetraprolin (TTP, in radiation-induced TNF-α production by macrophages. For in vitro studies we irradiated (4 Gy either a mouse lung macrophage cell line, MH-S or macrophages isolated from TTP knockout mice, and studied the effects of radiation on TTP and TNF-α levels. To study the in vivo relevance, mouse lungs were irradiated with a single dose (15 Gy and assessed at varying times for TTP alterations. Irradiation of MH-S cells caused TTP to undergo an inhibitory phosphorylation at Ser-178 and proteasome-mediated degradation, which resulted in increased TNF-α mRNA stabilization and secretion. Similarly, MH-S cells treated with TTP siRNA or macrophages isolated from ttp (-/- mice had higher basal levels of TNF-α, which was increased minimally after irradiation. Conversely, cells overexpressing TTP mutants defective in undergoing phosphorylation released significantly lower levels of TNF-α. Inhibition of p38, a known kinase for TTP, by either siRNA or a small molecule inhibitor abrogated radiation-induced TNF-α release by MH-S cells. Lung irradiation induced TTP(Ser178 phosphorylation and protein degradation and a simultaneous increase in TNF-α production in C57BL/6 mice starting 24 h post-radiation. In conclusion, irradiation of lung macrophages causes TTP inactivation via p38-mediated phosphorylation and proteasome-mediated degradation, leading to TNF-α production. These findings suggest that agents capable of blocking TTP phosphorylation or stabilizing TTP after irradiation could decrease RILT.

  12. Neutrophil and Alveolar Macrophage-Mediated Innate Immune Control of Legionella pneumophila Lung Infection via TNF and ROS.

    Directory of Open Access Journals (Sweden)

    Pascal Ziltener

    2016-04-01

    Full Text Available Legionella pneumophila is a facultative intracellular bacterium that lives in aquatic environments where it parasitizes amoeba. However, upon inhalation of contaminated aerosols it can infect and replicate in human alveolar macrophages, which can result in Legionnaires' disease, a severe form of pneumonia. Upon experimental airway infection of mice, L. pneumophila is rapidly controlled by innate immune mechanisms. Here we identified, on a cell-type specific level, the key innate effector functions responsible for rapid control of infection. In addition to the well-characterized NLRC4-NAIP5 flagellin recognition pathway, tumor necrosis factor (TNF and reactive oxygen species (ROS are also essential for effective innate immune control of L. pneumophila. While ROS are essential for the bactericidal activity of neutrophils, alveolar macrophages (AM rely on neutrophil and monocyte-derived TNF signaling via TNFR1 to restrict bacterial replication. This TNF-mediated antibacterial mechanism depends on the acidification of lysosomes and their fusion with L. pneumophila containing vacuoles (LCVs, as well as caspases with a minor contribution from cysteine-type cathepsins or calpains, and is independent of NLRC4, caspase-1, caspase-11 and NOX2. This study highlights the differential utilization of innate effector pathways to curtail intracellular bacterial replication in specific host cells upon L. pneumophila airway infection.

  13. Neutrophil and Alveolar Macrophage-Mediated Innate Immune Control of Legionella pneumophila Lung Infection via TNF and ROS

    Science.gov (United States)

    Ziltener, Pascal; Reinheckel, Thomas; Oxenius, Annette

    2016-01-01

    Legionella pneumophila is a facultative intracellular bacterium that lives in aquatic environments where it parasitizes amoeba. However, upon inhalation of contaminated aerosols it can infect and replicate in human alveolar macrophages, which can result in Legionnaires’ disease, a severe form of pneumonia. Upon experimental airway infection of mice, L. pneumophila is rapidly controlled by innate immune mechanisms. Here we identified, on a cell-type specific level, the key innate effector functions responsible for rapid control of infection. In addition to the well-characterized NLRC4-NAIP5 flagellin recognition pathway, tumor necrosis factor (TNF) and reactive oxygen species (ROS) are also essential for effective innate immune control of L. pneumophila. While ROS are essential for the bactericidal activity of neutrophils, alveolar macrophages (AM) rely on neutrophil and monocyte-derived TNF signaling via TNFR1 to restrict bacterial replication. This TNF-mediated antibacterial mechanism depends on the acidification of lysosomes and their fusion with L. pneumophila containing vacuoles (LCVs), as well as caspases with a minor contribution from cysteine-type cathepsins or calpains, and is independent of NLRC4, caspase-1, caspase-11 and NOX2. This study highlights the differential utilization of innate effector pathways to curtail intracellular bacterial replication in specific host cells upon L. pneumophila airway infection. PMID:27105352

  14. Priming astrocytes with TNF enhances their susceptibility to Trypanosoma cruzi infection and creates a self-sustaining inflammatory milieu.

    Science.gov (United States)

    Silva, Andrea Alice; Silva, Rafael Rodrigues; Gibaldi, Daniel; Mariante, Rafael Meyer; Dos Santos, Jessica Brandão; Pereira, Isabela Resende; Moreira, Otacílio Cruz; Lannes-Vieira, Joseli

    2017-09-06

    , anti-TNF therapy reduced the number of amastigote nests in the brain. Our data implicate TNF as a promoter of T. cruzi invasion of mouse and human astrocytes. Moreover, the TNF-enriched inflammatory milieu and enhanced TNFR1 expression may favor TNF signaling, astrocyte colonization by T. cruzi and egression of trypomastigotes. Therefore, in T. cruzi infection, a self-sustaining TNF-induced inflammatory circuit may perpetuate the parasite cycle in the CNS and ultimately promote cytokine-driven behavioral alterations.

  15. Biological anti-TNF drugs

    DEFF Research Database (Denmark)

    Prado, Mônica Simon; Bendtzen, Klaus; Andrade, Luis Eduardo Coelho

    2017-01-01

    is frequently caused by antibodies against immune-biologicals, known as anti-drug antibodies (ADA). ADA that neutralize circulating immune-biologicals and/or promote their clearance can reduce treatment efficacy. Furthermore, ADA can induce adverse events by diverse immunological mechanisms. This review...... provides a comprehensive overview of ADA in rheumatoid arthritis patients treated with anti-TNF immune-biologicals, and explores the concept of therapeutic drug monitoring (TDM) as an effective strategy to improve therapeutic management. Expert opinion: Monitoring circulating ADA and therapeutic immune......-biological drugs is helpful when evaluating patients with secondary failure. However, immunological tests for ADA vary considerably regarding their ability to detect different types of ADA. Several assays are not designed to determine ADA-induced drug neutralizing capacity, and they may report clinically non...

  16. Effect of gene-targeted mutation in TNF receptor (p55) on contact hypersensitivity and ultraviolet B-induced immunosuppression

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Seiji; Wang, Binghe; Fujisawa, Hiroshi [Univ. of Toronto, Ontario (Canada)] [and others

    1995-10-15

    Tumor necrosis factor {alpha} (TNF-{alpha}) is a pleiotropic proinflammatory cytokine. TNF-{alpha} has been implicated in the pathogenesis of delayed-type hypersensitivity reactions such as allergic contact hypersensitivity and has been suggested as a mediator of ultraviolet B (UVB)-induced immunosuppression. Conflicting reports, however, exist concerning the effects of TNF-{alpha} on contact hypersensitivity (CHS). To determine the role of TNF-{alpha} in the generation and regulation of CHS, gene-targeted mutant mice lacking TNF-receptor (p55) gene (TNF-R1(-) mice) were treated with dinitrofluorobenzene (DNFB) to induce CHS. TNF-R1(-) mice showed significant hyperresponsiveness in CHS (152.8 {+-} 20.9%, p < 0.025) compared with normal syngeneic mice (C57BL/6) assessed by ear swelling. To determine whether UVB can induce suppression in TNF-R1(-) mice, mice were irradiated on the shaved abdomen with 96 ml/cm{sup 2} UVB and 3 days later they were painted with 0.5% DNFB (sensitization dose), followed 5 days later with 0.2% DNFB to the left ear (challenge dose). Significant suppression of CHS was observed both locally (sensitization on irradiated site) and systemically (sensitization on unirradiated site) in UVB-irradiated TNF-R1(-) mice as well as in normal mice. To rule out possible signaling through p75 TNF-R, the mice were treated with anti-TNF-{alpha} Ab (V1q), which can neutralize any TNF effects through either receptor. V1q had no effect on these phenomena observed in TNF-R1(-) mice. These results suggest that TNF-{alpha} plays a regulatory role in CHS but is not required to induce UVB-mediated immunosuppression. 45 refs., 5 figs.

  17. Human SR-BII mediates SAA uptake and contributes to SAA pro-inflammatory signaling in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Irina N Baranova

    Full Text Available Serum amyloid A (SAA is an acute phase protein with cytokine-like and chemotactic properties, that is markedly up-regulated during various inflammatory conditions. Several receptors, including FPRL-1, TLR2, TLR4, RAGE, class B scavenger receptors, SR-BI and CD36, have been identified as SAA receptors. This study provides new evidence that SR-BII, splice variant of SR-BI, could function as an SAA receptor mediating its uptake and pro-inflammatory signaling. The uptake of Alexa Fluor488 SAA was markedly (~3 fold increased in hSR-BII-expressing HeLa cells when compared with mock-transfected cells. The levels of SAA-induced interleukin-8 secretion by hSR-BII-expressing HEK293 cells were also significantly (~3-3.5 fold higher than those detected in control cells. Moderately enhanced levels of phosphorylation of all three mitogen-activated protein kinases, ERK1/2, and p38 and JNK, were observed in hSR-BII-expressing cells following SAA stimulation when compared with control wild type cells. Transgenic mice with pLiv-11-directed liver/kidney overexpression of hSR-BI or hSR-BII were used to assess the in vivo role of each receptor in SAA-induced pro-inflammatory response in these organs. Six hours after intraperitoneal SAA injection both groups of transgenic mice demonstrated markedly higher (~2-5-fold expression levels of inflammatory mediators in the liver and kidney compared to wild type mice. Histological examinations of hepatic and renal tissue from SAA-treated mice revealed moderate level of damage in the liver of both transgenic but not in the wild type mice. Activities of plasma transaminases, biomarkers of liver injury, were also moderately higher in hSR-B transgenic mice when compared to wild type mice. Our findings identify hSR-BII as a functional SAA receptor that mediates SAA uptake and contributes to its pro-inflammatory signaling via the MAPKs-mediated signaling pathways.

  18. Phosphorylation of Galpha11 protein contributes to agonist-induced desensitization of 5-HT2A receptor signaling.

    Science.gov (United States)

    Shi, Ju; Zemaitaitis, Bozena; Muma, Nancy A

    2007-01-01

    Agonist treatment causes desensitization of many G protein-coupled receptor systems. Recent advances have delineated changes in receptors in the desensitization response; however, the role of G proteins remains unclear. We investigated the role of phosphorylation of Galpha q/11 proteins in agonist-induced desensitization of serotonin 2A (5-HT2A) receptors. In an embryonic rat cortical cell line (A1A1v), 24-h treatment with 100 nM (-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl (DOI), a 5-HT(2A/2C) receptor agonist, decreased DOI-stimulated inositol phosphate accumulation and increased the phosphorylation of Galpha q/11 proteins, as demonstrated by immunoprecipitation of Galpha q/11 and both incorporation of 32P phosphate and labeling with a S/T/Y phosphorylation-dependent antibody. Treatment with DOI for 30 min induced desensitization but did not increase phosphorylation of Galpha q/11 proteins, suggesting that different mechanisms are involved in desensitization after short- and long-term treatments. Mutation of S154A in a protein kinase C (PKC) and calcium/calmodulin dependent kinase (CaMK) consensus site in Galpha11 significantly reduced DOI-stimulated phosphorylation of Galpha11 and DOI-induced desensitization of 5-HT2A receptor signaling. Inhibition of PKC and CaMK attenuated phosphorylation of Galpha q/11 proteins and DOI-induced desensitization of 5-HT2A receptors. Expression of Galpha11 S154D, a phosphorylation mimic, reduced DOI-stimulated inositol phosphate accumulation. DOI treatment for 24 h also produced heterologous desensitization, as indicated by decreased bradykinin-stimulated inositol phosphate accumulation. These data suggest that phosphorylation of Galpha11 protein by PKC and CaMK contributes to agonist-induced homologous desensitization of 5-HT2A receptor signaling as well as heterologous desensitization. The phosphorylation of Galpha protein represents a novel mechanism involved in regulation of receptor signaling and agonist

  19. Assay of S for Quantitation of PEG and TNF Ligated Au Nanoparticles using ID-HR-MC-ICP-MS

    Science.gov (United States)

    Mann, J. L.; Vocke, R. D.; Newman, J. D.; Kelly, W. R.

    2009-12-01

    measurements in high-resolution (HR) mode to resolve these interferences reduces the overall signal intensity. To further reduce the effects of the interferences and limit the signal attentuation resulting from running in HR mode, an Aridus II desolvator was used to introduce the sample as a dry aerosol. The signal intensities obtained on the most abundant isotope mass 32 are typically 6 x 10-11 A per ug S/g solution. A small sulfur hydride, however, remains 3 x 10-14 A at mass 33S. By using a 33S enriched spike for isotope dilution, the overall effect of the hydride on mass 33 is significantly reduced (mass bias determination. Using an iterative procedure, the mass bias and measured 32S/33S ratios were successively corrected until the values converged. This calculation removes the spike contribution to the sample to obtain the mass bias corrected 33S/32S. The corrected 33S/32S ratios were then used in the isotope dilution calculation for S quantitation. Preliminary results on pure sulfur solutions and PEG solutions at a concentration of approximately 1 ppm S (≈ 38 nM PEG/g), show comparable results with rsd’s in the 0.5 to 1% range.

  20. Calpain-2 Regulates TNF-α Expression Associated with Neuropathic Pain Following Motor Nerve Injury.

    Science.gov (United States)

    Chen, Shao-Xia; Liao, Guang-Jie; Yao, Pei-Wen; Wang, Shao-Kun; Li, Yong-Yong; Zeng, Wei-An; Liu, Xian-Guo; Zang, Ying

    2018-02-22

    Both calpain-2 (CALP2) and tumor necrosis factor-α (TNF-α) contribute to persistent bilateral hypersensitivity in animals subjected to L5 ventral root transection (L5-VRT), a model of selective motor fiber injury without sensory nerve damage. However, specific upstream mechanisms regulating TNF-α overexpression and possible relationships linking CALP2 and TNF-α have not yet been investigated in this model. We examined changes in CALP2 and TNF-α protein levels and alterations in bilateral mechanical threshold within 24 h following L5-VRT model injury. We observed robust elevation of CALP2 and TNF-α in bilateral dorsal root ganglias (DRGs) and bilateral spinal cord neurons. CALP2 and TNF-α protein induction by L5-VRT were significantly inhibited by pretreatment using the calpain inhibitor MDL28170. Administration of CALP2 to rats without nerve injury further supported a role of CALP2 in the regulation of TNF-α expression. Although clinical trials of calpain inhibition therapy for alleviation of neuropathic pain induced by motor nerve injury have not yet shown success, our observations linking CALP2 and TNF-α provide a framework of a systems approach based perspective for treating neuropathic pain. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Macrocyclic θ-defensins suppress tumor necrosis factor-α (TNF-α) shedding by inhibition of TNF-α-converting enzyme.

    Science.gov (United States)

    Schaal, Justin B; Maretzky, Thorsten; Tran, Dat Q; Tran, Patti A; Tongaonkar, Prasad; Blobel, Carl P; Ouellette, André J; Selsted, Michael E

    2018-02-23

    Theta-defensins (θ-defensins) are macrocyclic peptides expressed exclusively in granulocytes and selected epithelia of Old World monkeys. They contribute to anti-pathogen host defense responses by directly killing a diverse range of microbes. Of note, θ-defensins also modulate microbe-induced inflammation by affecting the production of soluble tumor necrosis factor (sTNF) and other proinflammatory cytokines. Here, we report that natural rhesus macaque θ-defensin (RTD) isoforms regulate sTNF cellular release by inhibiting TNF-α-converting enzyme (TACE; also known as a d isintegrin a nd m etalloprotease 17; ADAM17), the primary pro-TNF sheddase. Dose-dependent inhibition of cellular TACE activity by RTDs occurred when leukocytes were stimulated with live Escherichia coli cells as well as numerous Toll-like receptor agonists. Moreover, the relative inhibitory potencies of the RTD isoforms strongly correlated with their suppression of TNF release by stimulated blood leukocytes and THP-1 monocytes. RTD isoforms also inhibited ADAM10, a sheddase closely related to TACE. TACE inhibition was abrogated by introducing a single opening in the RTD-1 backbone, demonstrating that the intact macrocycle is required for enzyme inhibition. Enzymologic analyses showed that RTD-1 is a fast binding, reversible, non-competitive inhibitor of TACE. We conclude that θ-defensin-mediated inhibition of pro-TNF proteolysis by TACE represents a rapid mechanism for the regulation of sTNF and TNF-dependent inflammatory pathways. Molecules with structural and functional features mimicking those of θ-defensins may have clinical utility as TACE inhibitors for managing TNF-driven diseases. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. TNF-α promotes colon cancer cell migration and invasion by upregulating TROP-2.

    Science.gov (United States)

    Zhao, Peng; Zhang, Zhongtao

    2018-03-01

    High levels of tumor-associated calcium signal transduction protein (TROP)-2 have been demonstrated to be strongly associated with tumor necrosis factor (TNF)-α levels in colon cancer. In the present study, the effect of TNF-α on the regulation of TROP-2 expression and its effect in colon cancer cell migration and invasion were investigated in vitro . TROP-2 protein levels were evaluated in HCT-116 human colon cancer cells cultured with various concentrations of TNF-α using western blot analysis. Changes in the migratory and invasive potential of the cells were evaluated using a wound healing and transwell assay, respectively. Then, TROP-2 expression was downregulated in cells by use of siRNA, and TROP-2 knockdown was confirmed at the mRNA and protein level by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The migration and invasion potential of cells transfected with TROP-2 siRNA was also evaluated. Levels of several mitogen-activated protein kinase proteins, namely p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK), were detected in cells treated with TNF-α using western blot analysis. The results demonstrated that TROP-2 protein levels increased in cells treated with lower concentrations of TNF-α, but decreased in cells treated with higher concentrations of TNF-α, compared with untreated control. Maximum TROP-2 levels were observed in cells treated with 20 µg/l TNF-α. Migration and invasion were enhanced in cells treated with 20 µg/l TNF-α. When TROP-2 was silenced in colon cancer cells by siRNA, migration and invasion were significantly decreased compared with control cells. TNF-α stimulation activated the ERK1/2 pathway, but did not significantly affect p38 and JNK phosphorylation levels. Treatment with a specific ERK1/2 inhibitor suppressed the TNF-α-induced upregulation of TROP-2 and the TNF-α-induced colon cancer cell migration and invasion. In conclusion, the

  3. Decreased inducibility of TNF expression in lipid-loaded macrophages

    Directory of Open Access Journals (Sweden)

    Kallin Bengt

    2002-10-01

    Full Text Available Abstract Background Inflammation and immune responses are considered to be very important in the pathogenesis of atherosclerosis. Lipid accumulation in macrophages of the arterial intima is a characteristic feature of atherosclerosis which can influence the inflammatory potential of macrophages. We studied the effects of lipid loading on the regulation of TNF expression in human monocyte-derived macrophages. Results In macrophages incubated with acetylated low density lipoprotein (ac-LDL for 2 days, mRNA expression of TNF in cells stimulated with TNF decreased by 75%. In cell cultures stimulated over night with IL-1β, lipid loading decreased secretion of TNF into culture medium by 48%. These results suggest that lipid accumulation in macrophages makes them less responsive to inflammatory stimuli. Decreased basal activity and inducibility of transcription factor AP-1 was observed in lipid-loaded cells, suggesting a mechanism for the suppression of cytokine expression. NF-κB binding activity and inducibility were only marginally affected by ac-LDL. LDL and ac-LDL did not activate PPARγ. In contrast, oxidized LDL stimulated AP-1 and PPARγ but inhibited NF-κB, indicating that the effects of lipid loading with ac-LDL were not due to oxidation of lipids. Conclusions Accumulation of lipid, mainly cholesterol, results in down-regulation of TNF expression in macrophages. Since monocytes are known to be activated by cell adhesion, these results suggest that foam cells in atherosclerotic plaques may contribute less potently to an inflammatory reaction than newly arrived monocytes/macrophages.

  4. Opposing Actions of Fgf8a on Notch Signaling Distinguish Two Muller Glial Cell Populations that Contribute to Retina Growth and Regeneration

    Directory of Open Access Journals (Sweden)

    Jin Wan

    2017-04-01

    Full Text Available The teleost retina grows throughout life and exhibits a robust regenerative response following injury. Critical to both these events are Muller glia (or, Muller glial cells; MGs, which produce progenitors for retinal growth and repair. We report that Fgf8a may be an MG niche factor that acts through Notch signaling to regulate spontaneous and injury-dependent MG proliferation. Remarkably, forced Fgf8a expression inhibits Notch signaling and stimulates MG proliferation in young tissue but increases Notch signaling and suppresses MG proliferation in older tissue. Furthermore, cessation of Fgf8a signaling enhances MG proliferation in both young and old retinal tissue. Our study suggests that multiple MG populations contribute to retinal growth and regeneration, and it reveals a previously unappreciated role for Fgf8a and Notch signaling in regulating MG quiescence, activation, and proliferation.

  5. Opposing actions of Fgf8a on Notch signaling distinguish two Muller glial cell populations that contribute to retina growth and regeneration

    Science.gov (United States)

    Wan, Jin; Goldman, Daniel

    2017-01-01

    Summary The teleost retina grows throughout life and exhibits a robust regenerative response following injury. Critical to both these events are Muller glia (MG) that produce progenitors for retinal growth and repair. We report that Fgf8a may be a MG niche factor that acts through Notch signaling to regulate spontaneous and injury-dependent MG proliferation. Remarkably, forced Fgf8a expression inhibits Notch signaling and stimulates MG proliferation in young tissue, but increases Notch signaling and suppresses MG proliferation in older tissue. Furthermore, cessation of Fgf8a signaling enhances MG proliferation in both young and old retinal tissue. Our study suggests multiple MG populations contribute to retinal growth and regeneration, and reveals a previously unappreciated role for Fgf8a and Notch signaling in regulating MG quiescence, activation and proliferation. PMID:28445734

  6. TNF-induced necroptosis requires the plasma membrane localization of the MLKL protein | Center for Cancer Research

    Science.gov (United States)

    The cell signaling protein tumor necrosis factor (TNF), produced by white blood cells, promotes inflammation and immunity processes such as fever and is involved in tumorigenesis and apoptosis (programmed cell death). However, dysregulation of TNF can also lead to another form of programmed cell death called necroptosis, which is characterized by a rise in intracellular Ca2+, generation of reactive oxygen species (ROS), intracellular acidity, depletion of ATP, and, eventually, plasma membrane rupture. TNF-induced necroptosis has been associated with a wide variety of diseases including neurodegenerative diseases, major depression, rheumatoid arthritis, and cancer. Whereas the signaling mechanisms underlying TNF-induced apoptosis have largely been determined, the events precipitating in TNF-initiated necroptosis are still unknown.

  7. Cyclopropane fatty acid synthase mutants of probiotic human-derived Lactobacillus reuteri are defective in TNF inhibition.

    Science.gov (United States)

    Jones, Sara E; Whitehead, Kristi; Saulnier, Delphine; Thomas, Carissa M; Versalovic, James; Britton, Robert A

    2011-01-01

    Although commensal microbes have been shown to modulate host immune responses, many of the bacterial factors that mediate immune regulation remain unidentified. Select strains of human-derived Lactobacillus reuteri synthesize immunomodulins that potently inhibit production of the inflammatory cytokine TNF. In this study, genetic and genomic approaches were used to identify and investigate L. reuteri genes required or human TNF immunomodulatory activity. Analysis of membrane fatty acids from multiple L. reuteri strains cultured in MRS medium showed that only TNF inhibitory strains produced the cyclopropane fatty acid (CFA) lactobacillic acid. The enzyme cyclopropane fatty acid synthase is required for synthesis of CFAs such as lactobacillic acid, therefore the cfa gene was inactivated and supernatants from the cfa mutant strain were assayed for TNF inhibitory activity. We found that supernatants from the wild-type strain, but not the cfa mutant, suppressed TNF production by activated THP-1 human monocytoid cells Although this suggested a direct role for lactobacillic acid in immunomodulation, purified lactobacillic acid did not suppress TNF at physiologically relevant concentrations. We further analyzed TNF inhibitory and TNF non-inhibitory strains under different growth conditions and found that lactobacillic acid production did not correlate with TNF inhibition. These results indicate that cfa indirectly contributed to L. reuter immunomodulatory activity and suggest that other mechanisms, such as decreased membrane fluidity or altered expression of immunomodulins, result in the loss of TNF inhibitory activity. By increasing our understanding of immunomodulation by probiotic species, beneficial microbes can be rationally selected to alleviate intestinal inflammation.

  8. ST6Gal-I sialyltransferase promotes tumor necrosis factor (TNF)-mediated cancer cell survival via sialylation of the TNF receptor 1 (TNFR1) death receptor.

    Science.gov (United States)

    Holdbrooks, Andrew T; Britain, Colleen M; Bellis, Susan L

    2018-02-02

    Activation of the tumor necrosis factor receptor 1 (TNFR1) death receptor by TNF induces either cell survival or cell death. However, the mechanisms mediating these distinct outcomes remain poorly understood. In this study, we report that the ST6Gal-I sialyltransferase, an enzyme up-regulated in numerous cancers, sialylates TNFR1 and thereby protects tumor cells from TNF-induced apoptosis. Using pancreatic and ovarian cancer cells with ST6Gal-I knockdown or overexpression, we determined that α2-6 sialylation of TNFR1 had no effect on early TNF-induced signaling events, including the rapid activation of NF-κB, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and Akt (occurring within 15 min). However, upon extended TNF treatment (6-24 h), cells with high ST6Gal-I levels exhibited resistance to TNF-induced apoptosis, as indicated by morphological evidence of cell death and decreased activation of caspases 8 and 3. Correspondingly, at these later time points, high ST6Gal-I expressers displayed sustained activation of the survival molecules Akt and NF-κB. Additionally, extended TNF treatment resulted in the selective enrichment of clonal variants with high ST6Gal-I expression, further substantiating a role for ST6Gal-I in cell survival. Given that TNFR1 internalization is known to be essential for apoptosis induction, whereas survival signaling is initiated by TNFR1 at the plasma membrane, we examined TNFR1 localization. The α2-6 sialylation of TNFR1 was found to inhibit TNF-induced TNFR1 internalization. Thus, by restraining TNFR1 at the cell surface via sialylation, ST6Gal-I acts as a functional switch to divert signaling toward survival. These collective findings point to a novel glycosylation-dependent mechanism that regulates the cellular response to TNF and may promote cancer cell survival within TNF-rich tumor microenvironments. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. TNF is required for TLR ligand–mediated but not protease-mediated allergic airway inflammation

    Science.gov (United States)

    Whitehead, Gregory S.; Thomas, Seddon Y.; Shalaby, Karim H.; Nakano, Keiko; Moran, Timothy P.; Ward, James M.; Flake, Gordon P.; Cook, Donald N.

    2017-01-01

    Asthma is associated with exposure to a wide variety of allergens and adjuvants. The extent to which overlap exists between the cellular and molecular mechanisms triggered by these various agents is poorly understood, but it might explain the differential responsiveness of patients to specific therapies. In particular, it is unclear why some, but not all, patients benefit from blockade of TNF. Here, we characterized signaling pathways triggered by distinct types of adjuvants during allergic sensitization. Mice sensitized to an innocuous protein using TLR ligands or house dust extracts as adjuvants developed mixed eosinophilic and neutrophilic airway inflammation and airway hyperresponsiveness (AHR) following allergen challenge, whereas mice sensitized using proteases as adjuvants developed predominantly eosinophilic inflammation and AHR. TLR ligands, but not proteases, induced TNF during allergic sensitization. TNF signaled through airway epithelial cells to reprogram them and promote Th2, but not Th17, development in lymph nodes. TNF was also required during the allergen challenge phase for neutrophilic and eosinophilic inflammation. In contrast, TNF was dispensable for allergic airway disease in a protease-mediated model of asthma. These findings might help to explain why TNF blockade improves lung function in only some patients with asthma. PMID:28758900

  10. TNF-α-induced protein 3 (TNFAIP3)/A20 acts as a master switch in TNF-α blockade-driven IL-17A expression.

    Science.gov (United States)

    Urbano, Paulo C M; Aguirre-Gamboa, Raúl; Ashikov, Angel; van Heeswijk, Bennie; Krippner-Heidenreich, Anja; Tijssen, Henk; Li, Yang; Azevedo, Valderilio F; Smits, Lisa J T; Hoentjen, Frank; Joosten, Irma; Koenen, Hans J P M

    2017-12-14

    Anti-TNF inhibitors successfully improve the quality of life of patients with inflammatory disease. Unfortunately, not all patients respond to anti-TNF therapy, and some patients show paradoxical immune side effects, which are poorly understood. Surprisingly, anti-TNF agents were shown to promote IL-17A production with as yet unknown clinical implications. We sought to investigate the molecular mechanism underlying anti-TNF-driven IL-17A expression and the clinical implications of this phenomenon. Fluorescence-activated cell sorting, RNA sequencing, quantitative real-time PCR, Western blotting, small interfering RNA interference, and kinase inhibitors were used to study the molecular mechanisms in isolated human CD4 + T cells from healthy donors. The clinical implication was studied in blood samples of patients with inflammatory bowel disease (IBD) receiving anti-TNF therapy. Here we show that anti-TNF treatment results in inhibition of the anti-inflammatory molecule TNF-α-induced protein 3 (TNFAIP3)/A20 in memory CD4 + T cells. We found an inverse relationship between TNFAIP3/A20 expression levels and IL-17A production. Inhibition of TNFAIP3/A20 promotes kinase activity of p38 mitogen-activated protein kinase and protein kinase C, which drives IL-17A expression. Regulation of TNFAIP3/A20 expression and cognate IL-17A production in T cells are specifically mediated through TNF receptor 2 signaling. Ex vivo, in patients with IBD treated with anti-TNF, we found further evidence for an inverse relationship between TNFAIP3/A20 expression levels and IL-17A-producing T cells. Anti-TNF treatment interferes in the TNFAIP3/A20-mediated anti-inflammatory feedback loop in CD4 + T cells and promotes kinase activity. This puts TNFAIP3/A20, combined with IL-17A expression, on the map as a potential tool for predicting therapy responsiveness or side effects of anti-TNF therapy. Moreover, it provides novel targets related to TNFAIP3/A20 activity for superior therapeutic regimens

  11. Role of TNF-alpha during central sensitization in preclinical studies.

    Science.gov (United States)

    Andrade, Pablo; Visser-Vandewalle, Veerle; Hoffmann, Carolin; Steinbusch, Harry W M; Daemen, Marc A; Hoogland, Govert

    2011-10-01

    Tumor necrosis factor-alpha (TNF-α) is a principal mediator in pro-inflammatory processes that involve necrosis, apoptosis and proliferation. Experimental and clinical evidence demonstrate that peripheral nerve injury results in activation and morphological changes of microglial cells in the spinal cord. These adjustments occur in order to initiate an inflammatory cascade in response to the damage. Between the agents involved in this reaction, TNF-α is recognized as a key player in this process as it not only modulates lesion formation, but also because it is suggested to induce nociceptive signals. Nowadays, even though the function of TNF-α in inflammation and pain production seems to be generally accepted, diverse sources of literature point to different pathways and outcomes. In this review, we systematically searched and reviewed original articles from the past 10 years on animal models of peripheral nervous injury describing TNF-α expression in neural tissue and pain behavior.

  12. Beta1 integrins activate a MAPK signalling pathway in neural stem cells that contributes to their maintenance

    DEFF Research Database (Denmark)

    Campos, Lia S; Leone, Dino P; Relvas, Joao B

    2004-01-01

    , signalling is required for neural stem cell maintenance, as assessed by neurosphere formation, and inhibition or genetic ablation of beta1 integrin using cre/lox technology reduces the level of MAPK activity. We conclude that integrins are therefore an important part of the signalling mechanisms that control...

  13. Immunogenicity of Anti-TNF-α Biotherapies

    DEFF Research Database (Denmark)

    Bendtzen, Klaus

    2015-01-01

    Specific inhibition of the cytokine, tumor necrosis factor-α (TNF), has revolutionized the treatment of patients with several autoimmune diseases, and genetically engineered anti-TNF antibody constructs now constitute a heavy medicinal expenditure in many countries. Unfortunately, up to 30...... of protein drugs. The use of therapeutic strategies based on anti-TNF drug levels and ADA rather than dose-escalation has also proven to be cost-effective, as this allows individualized patient-tailored strategies rather than the current universal approach to loss of response. The objective of the present...... article - and the accompanying article - is to discuss the reasons for recommending assessments of circulating drug and ADA levels in patients treated with anti-TNF biopharmaceuticals and to detail some of the methodological issues that obscure cost-effective and safer therapies....

  14. TNF-α promotes extracellular vesicle release in mouse astrocytes through glutaminase.

    Science.gov (United States)

    Wang, Kaizhe; Ye, Ling; Lu, Hongfang; Chen, Huili; Zhang, Yanyan; Huang, Yunlong; Zheng, Jialin C

    2017-04-20

    Extracellular vesicles (EVs) are membrane-contained vesicles shed from cells. EVs contain proteins, lipids, and nucleotides, all of which play important roles in intercellular communication. The release of EVs is known to increase during neuroinflammation. Glutaminase, a mitochondrial enzyme that converts glutamine to glutamate, has been implicated in the biogenesis of EVs. We have previously demonstrated that TNF-α promotes glutaminase expression in neurons. However, the expression and the functionality of glutaminase in astrocytes during neuroinflammation remain unknown. We posit that TNF-α can promote the release of EVs in astrocytes through upregulation of glutaminase expression. Release of EVs, which was demonstrated by electron microscopy, nanoparticle tracking analysis (NTA), and Western Blot, increased in mouse astrocytes when treated with TNF-α. Furthermore, TNF-α treatment significantly upregulated protein levels of glutaminase and increased the production of glutamate, suggesting that glutaminase activity is increased after TNF-α treatment. Interestingly, pretreatment with a glutaminase inhibitor blocked TNF-α-mediated generation of reactive oxygen species in astrocytes, which indicates that glutaminase activity contributes to stress in astrocytes during neuroinflammation. TNF-α-mediated increased release of EVs can be blocked by either the glutaminase inhibitor, antioxidant N-acetyl-L-cysteine, or genetic knockout of glutaminase, suggesting that glutaminase plays an important role in astrocyte EV release during neuroinflammation. These findings suggest that glutaminase is an important metabolic factor controlling EV release from astrocytes during neuroinflammation.

  15. Circulating levels of TNF-alpha and IL-6-relation to truncal fat mass and muscle mass in healthy elderly individuals and in patients with type-2 diabetes

    DEFF Research Database (Denmark)

    Pedersen, Maria; Bruunsgaard, Helle; Weis, Nina

    2003-01-01

    The purpose of the current study was to test the hypothesis that an altered fat distribution in elderly healthy subjects and in patients with type-2 diabetes contributes to high circulating levels of interleukin (IL)-6 and tumor necrotic factor (TNF)-alpha, which secondly is related to lower musc...... that cytokines are partly derived from this adipose tissue bed. Furthermore, TNF-alpha was related to lower ASM and BCM, suggesting that TNF-alpha contributes to sarcopenia in ageing....

  16. Circulating levels of TNF-alpha and IL-6-relation to truncal fat mass and muscle mass in healthy elderly individuals and in patients with type-2-diabetes

    DEFF Research Database (Denmark)

    Pedersen, M; Bruunsgaard, H; Weis, Nina Margrethe

    2003-01-01

    The purpose of the current study was to test the hypothesis that an altered fat distribution in elderly healthy subjects and in patients with type-2 diabetes contributes to high circulating levels of interleukin (IL)-6 and tumor necrotic factor (TNF)-alpha, which secondly is related to lower musc...... that cytokines are partly derived from this adipose tissue bed. Furthermore, TNF-alpha was related to lower ASM and BCM, suggesting that TNF-alpha contributes to sarcopenia in ageing....

  17. Targeted Elimination of G Proteins and Arrestins Defines Their Specific Contributions to Both Intensity and Duration of G Protein-coupled Receptor Signaling.

    Science.gov (United States)

    Alvarez-Curto, Elisa; Inoue, Asuka; Jenkins, Laura; Raihan, Sheikh Zahir; Prihandoko, Rudi; Tobin, Andrew B; Milligan, Graeme

    2016-12-30

    G protein-coupled receptors (GPCRs) can initiate intracellular signaling cascades by coupling to an array of heterotrimeric G proteins and arrestin adaptor proteins. Understanding the contribution of each of these coupling options to GPCR signaling has been hampered by a paucity of tools to selectively perturb receptor function. Here we employ CRISPR/Cas9 genome editing to eliminate selected G proteins (Gα q and Gα 11 ) or arrestin2 and arrestin3 from HEK293 cells together with the elimination of receptor phosphorylation sites to define the relative contribution of G proteins, arrestins, and receptor phosphorylation to the signaling outcomes of the free fatty acid receptor 4 (FFA4). A lack of FFA4-mediated elevation of intracellular Ca 2+ in Gα q /Gα 11 -null cells and agonist-mediated receptor internalization in arrestin2/3-null cells confirmed previously reported canonical signaling features of this receptor, thereby validating the genome-edited HEK293 cells. FFA4-mediated ERK1/2 activation was totally dependent on G q / 11 but intriguingly was substantially enhanced for FFA4 receptors lacking sites of regulated phosphorylation. This was not due to a simple lack of desensitization of G q / 11 signaling because the G q / 11 -dependent calcium response was desensitized by both receptor phosphorylation and arrestin-dependent mechanisms, whereas a substantially enhanced ERK1/2 response was only observed for receptors lacking phosphorylation sites and not in arrestin2/3-null cells. In conclusion, we validate CRISPR/Cas9 engineered HEK293 cells lacking G q / 11 or arrestin2/3 as systems for GPCR signaling research and employ these cells to reveal a previously unappreciated interplay of signaling pathways where receptor phosphorylation can impact on ERK1/2 signaling through a mechanism that is likely independent of arrestins. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Impact of the Test Device on the Behavior of the Acoustic Emission Signals: Contribution of the Numerical Modeling to Signal Processing

    Science.gov (United States)

    Issiaka Traore, Oumar; Cristini, Paul; Favretto-Cristini, Nathalie; Pantera, Laurent; Viguier-Pla, Sylvie

    2018-01-01

    In a context of nuclear safety experiment monitoring with the non destructive testing method of acoustic emission, we study the impact of the test device on the interpretation of the recorded physical signals by using spectral finite element modeling. The numerical results are validated by comparison with real acoustic emission data obtained from previous experiments. The results show that several parameters can have significant impacts on acoustic wave propagation and then on the interpretation of the physical signals. The potential position of the source mechanism, the positions of the receivers and the nature of the coolant fluid have to be taken into account in the definition a pre-processing strategy of the real acoustic emission signals. In order to show the relevance of such an approach, we use the results to propose an optimization of the positions of the acoustic emission sensors in order to reduce the estimation bias of the time-delay and then improve the localization of the source mechanisms.

  19. Contributions of structural connectivity and cerebrovascular parameters to functional magnetic resonance imaging signals in mice at rest and during sensory paw stimulation.

    Science.gov (United States)

    Schroeter, Aileen; Grandjean, Joanes; Schlegel, Felix; Saab, Bechara J; Rudin, Markus

    2017-07-01

    Previously, we reported widespread bilateral increases in stimulus-evoked functional magnetic resonance imaging signals in mouse brain to unilateral sensory paw stimulation. We attributed the pattern to arousal-related cardiovascular changes overruling cerebral autoregulation thereby masking specific signal changes elicited by local neuronal activity. To rule out the possibility that interhemispheric neuronal communication might contribute to bilateral functional magnetic resonance imaging responses, we compared stimulus-evoked functional magnetic resonance imaging responses to unilateral hindpaw stimulation in acallosal I/LnJ, C57BL/6, and BALB/c mice. We found bilateral blood-oxygenation-level dependent signal changes in all three strains, ruling out a dominant contribution of transcallosal communication as reason for bilaterality. Analysis of functional connectivity derived from resting-state functional magnetic resonance imaging, revealed that bilateral cortical functional connectivity is largely abolished in I/LnJ animals. Cortical functional connectivity in all strains correlated with structural connectivity in corpus callosum as revealed by diffusion tensor imaging. Given the profound influence of systemic hemodynamics on stimulus-evoked functional magnetic resonance imaging outcomes, we evaluated whether functional connectivity data might be affected by cerebrovascular parameters, i.e. baseline cerebral blood volume, vascular reactivity, and reserve. We found that effects of cerebral hemodynamics on functional connectivity are largely outweighed by dominating contributions of structural connectivity. In contrast, contributions of transcallosal interhemispheric communication to the occurrence of ipsilateral functional magnetic resonance imaging response of equal amplitude to unilateral stimuli seem negligible.

  20. SH3BP2 cherubism mutation potentiates TNF-α-induced osteoclastogenesis via NFATc1 and TNF-α-mediated inflammatory bone loss

    Science.gov (United States)

    Mukai, Tomoyuki; Ishida, Shu; Ishikawa, Remi; Yoshitaka, Teruhito; Kittaka, Mizuho; Gallant, Richard; Lin, Yi-Ling; Rottapel, Robert; Brotto, Marco; Reichenberger, Ernst J.; Ueki, Yasuyoshi

    2014-01-01

    Cherubism (OMIM#118400) is a genetic disorder with excessive jawbone resorption caused by mutations in the signaling adaptor protein SH3BP2. Studies on the mouse model for cherubism carrying a P416R knock-in mutation have revealed that mutant SH3BP2 enhances TNF-α production and RANKL-induced osteoclast differentiation in myeloid cells. TNF-α is expressed in human cherubism lesions, which contain a large number of TRAP-positive multinucleated cells, and TNF-α plays a critical role in inflammatory bone destruction in homozygous cherubism mice (Sh3bp2KI/KI). The data suggest a pathophysiological relationship between mutant SH3BP2 and TNF-α-mediated bone loss by osteoclasts. Therefore, we investigated whether P416R mutant SH3BP2 is involved in TNF-α-mediated osteoclast formation and bone loss. Here, we show that bone marrow-derived M-CSF-dependent macrophages (BMMs) from the heterozygous cherubism mutant (Sh3bp2KI/+) mice are highly responsive to TNF-α and can differentiate into osteoclasts independently of RANKL in vitro by a mechanism that involves SYK and PLCγ2 phosphorylation, leading to increased nuclear translocation of NFATc1. The heterozygous cherubism mutation exacerbates bone loss with increased osteoclast formation in a mouse calvarial TNF-α injection model as well as in a human TNF-α transgenic mouse model (hTNFtg). SH3BP2 knockdown in RAW264.7 cells results in decreased TRAP-positive multinucleated cell formation. These findings suggest that the SH3BP2 cherubism mutation can cause jawbone destruction by promoting osteoclast formation in response to TNF-α expressed in cherubism lesions and that SH3BP2 is a key regulator for TNF-α-induced osteoclastogenesis. Inhibition of SH3BP2 expression in osteoclast progenitors could be a potential strategy for the treatment of bone loss in cherubism as well as in other inflammatory bone disorders. PMID:24916406

  1. Plasma TNF binding capacity in patients with juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Bjørnhart, Birgitte; Svenningsen, Pernille; Gudbrandsdottir, Sif

    2005-01-01

    Tumour necrosis factor (TNF)-alpha and TNF-beta, also called lymphotoxin (LT), are bound by soluble truncated TNF receptors (sTNFRI and II) that are released from cell surfaces and act as natural inhibitors of TNF-induced inflammation. We investigated the plasma levels of sTNFRI and II in parallel...

  2. Peripheral Tumor Necrosis Factor-Alpha (TNF-α) Modulates Amyloid Pathology by Regulating Blood-Derived Immune Cells and Glial Response in the Brain of AD/TNF Transgenic Mice.

    Science.gov (United States)

    Paouri, Evi; Tzara, Ourania; Kartalou, Georgia-Ioanna; Zenelak, Sofia; Georgopoulos, Spiros

    2017-05-17

    Increasing evidence has suggested that systemic inflammation along with local brain inflammation can play a significant role in Alzheimer's disease (AD) pathogenesis. Identifying key molecules that regulate the crosstalk between the immune and the CNS can provide potential therapeutic targets. TNF-α is a proinflammatory cytokine implicated in the pathogenesis of systemic inflammatory and neurodegenerative diseases, such as rheumatoid arthritis (RA) and AD. Recent studies have reported that anti-TNF-α therapy or RA itself can modulate AD pathology, although the underlying mechanism is unclear. To investigate the role of peripheral TNF-α as a mediator of RA in the pathogenesis of AD, we generated double-transgenic 5XFAD/Tg197 AD/TNF mice that develop amyloid deposits and inflammatory arthritis induced by human TNF-α (huTNF-α) expression. We found that 5XFAD/Tg197 mice display decreased amyloid deposition, compromised neuronal integrity, and robust brain inflammation characterized by extensive gliosis and elevated blood-derived immune cell populations, including phagocytic macrophages and microglia. To evaluate the contribution of peripheral huTNF-α in the observed brain phenotype, we treated 5XFAD/Tg197 mice systemically with infliximab, an anti-huTNF-α antibody that does not penetrate the blood-brain barrier and prevents arthritis. Peripheral inhibition of huTNF-α increases amyloid deposition, rescues neuronal impairment, and suppresses gliosis and recruitment of blood-derived immune cells, without affecting brain huTNF-α levels. Our data report, for the first time, a distinctive role for peripheral TNF-α in the modulation of the amyloid phenotype in mice by regulating blood-derived and local brain inflammatory cell populations involved in β-amyloid clearance. SIGNIFICANCE STATEMENT Mounting evidence supports the active involvement of systemic inflammation, in addition to local brain inflammation, in Alzheimer's disease (AD) progression. TNF-α is a

  3. Therapeutic TNF Inhibitors can Differentially Stabilize Trimeric TNF by Inhibiting Monomer Exchange

    Science.gov (United States)

    van Schie, Karin A.; Ooijevaar-de Heer, Pleuni; Dijk, Lisanne; Kruithof, Simone; Wolbink, Gertjan; Rispens, Theo

    2016-01-01

    Tumor necrosis factor (TNF) is a homotrimeric cytokine that is a key mediator of inflammation. It is unstable at physiological concentrations and slowly converts into an inactive form. Here, we investigated the mechanism of this process by using a Förster resonance energy transfer (FRET) assay that allowed monitoring of monomeric subunit exchange in time. We observed continuous exchange of monomeric subunits even at concentrations of TNF high enough to maintain its bioactivity. The kinetics of this process closely corresponds with the appearance of monomeric subunits and disappearance of trimeric TNF in time at ng/ml concentrations as monitored by high-performance size-exclusion chromatography (HP-SEC). Furthermore, of the five therapeutic TNF inhibitors that are currently used in the clinic, three (adalimumab, infliximab, etanercept) were found to completely inhibit the monomer exchange reaction and stabilize TNF trimers, whereas golimumab and certolizumab could not prevent monomer exchange, but did slow down the exchange process. These differences were not correlated with the affinities of the TNF inhibitors, measured with both surface plasmon resonance (SPR) and in fluid phase using fluorescence-assisted HP-SEC. The stabilizing effect of these TNF inhibitors might result in prolonged residual TNF bioactivity under conditions of incomplete blocking, as observed in vitro for adalimumab. PMID:27605058

  4. TLR2-dependent MyD88 signaling contributes to early host defense in murine Enterococcus faecium peritonitis

    NARCIS (Netherlands)

    Leendertse, Masja; Willems, Rob J. L.; Giebelen, Ida A. J.; van den Pangaart, Petra S.; Wiersinga, W. Joost; de Vos, Alex F.; Florquin, Sandrine; Bonten, Marc J. M.; van der Poll, Tom

    2008-01-01

    The incidence of infections with Enterococcus faecium is increasing worldwide. TLRs have been implicated in the recognition of pathogens and the initiation of an adequate innate immune response. We here sought to determine the roles of MyD88, the common adaptor protein involved in TLR signaling,

  5. Contribution of Pro-Inflammatory Cytokine Signaling within Midbrain Periaqueductal Gray to Pain Sensitivity in Parkinson's disease via GABAergic Pathway

    Directory of Open Access Journals (Sweden)

    Xianbo Zhuang

    2016-07-01

    Full Text Available Background/Aims: Hypersensitive pain response is often observed in patients with Parkinson's disease (PD; however, the mechanisms responsible for hyperalgesia are not well understood. Chronic neuroinflammation is one of the hallmarks of PD pathophysiology. Since the midbrain periaqueductal gray (PAG is an important component of the descending inhibitory pathway controlling on central pain transmission, we examined the role for pro-inflammatory cytokines (PICs system of PAG in regulating exaggerated pain evoked by PD. Methods: We used a rat model of PD to perform the experimental protocols. PD was induced by microinjection of 6-hydroxydopamine to lesion the left medial forebrain bundle. Pain responses to mechanical and thermal stimulation were first examined in control rats and PD rats. Then, ELISA and Western Blot analysis were used to determine PIC levels and their receptors expression. Results: Protein expression of IL-1β, IL-6 and TNF-α receptors (namely, IL-1R, IL-6R and TNFR subtype TNFR1 in the plasma membrane PAG of PD rats was upregulated, whereas the total expression of PIC receptors was not significantly altered. The ratio of membrane protein and total protein (IL-1R, IL-6R and TNFR1 was 1.48±0.15, 1.59±0.18 and 1.67±0.16 in PAG of PD rats (P < 0.05 vs. their respective controls. This was accompanied with increases of PICs of PAG, and decreases of GABA (623±21 ng/mg in control rats and 418±18 ng/mg in PD rats; P < 0.05 vs. control rats and withdrawal thresholds to mechanical and thermal stimuli. Our data further showed that the concentrations of GABA and withdrawal thresholds were largely restored by blocking those PIC receptors in PAG of PD rats. Stimulation of GABA receptors in PAG of PD rats also blunted a decrease in withdrawal thresholds. Conclusions: Our data suggest that upregulation of the membrane PIC receptor in the PAG of PD rats is likely to impair the descending inhibitory pathways in regulating pain transmission

  6. WNT/β-catenin pathway modulates the TNF-α-induced inflammatory response in bronchial epithelial cells.

    Science.gov (United States)

    Jang, Jaewoong; Jung, Yoonju; Chae, Seyeon; Chung, Sang-In; Kim, Seok-Min; Yoon, Yoosik

    2017-03-04

    In this study, TNF-α was found to activate the WNT/β-catenin pathway in BEAS-2B human bronchial epithelial cells. Levels of phospho-LRP6, Dvl-2, and phospho-GSK-3β were elevated, while that of Axin was reduced by TNF-α treatment. Nuclear translocation of β-catenin and the reporter activity of a β-catenin-responsive promoter were increased by TNF-α treatment. Under the same experimental conditions, TNF-α activated the NF-κB signaling, which includes the phosphorylation and degradation of IκB and nuclear translocation and target DNA binding of NF-κB, and it was found that an inhibitor of NF-κB activation, JSH-23, inhibited TNF-α-induced Wnt signaling as well as NF-κB signaling. It was also found that recombinant Wnt proteins induced NF-κB nuclear translocations and its target DNA binding, suggesting that Wnt signaling and NF-κB signaling were inter-connected. TNF-α-induced modulations of IκB and NF-κB as well as pro-inflammatory cytokine expression were significantly suppressed by the transfection of β-catenin siRNA compared to that of control siRNA. Transfection of a β-catenin expression plasmid augmented the TNF-α-induced modulations of IκB and NF-κB as well as pro-inflammatory cytokine expression. These results clearly demonstrated that the WNT/β-catenin pathway modulates the inflammatory response induced by TNF-α, suggesting that this pathway may be a useful target for the effective treatment of bronchial inflammation. Copyright © 2017. Published by Elsevier Inc.

  7. Signal Transducer and Activator of Transcription Factor 6 Signaling Contributes to Control Host Lung Pathology but Favors Susceptibility against Toxocara canis Infection

    Science.gov (United States)

    Faz-López, Berenice; Ledesma-Soto, Yadira; Romero-Sánchez, Yolanda; Calleja, Elsa; Martínez-Labat, Pablo; Terrazas, Luis I.

    2013-01-01

    Using STAT6−/− BALB/c mice, we have analyzed the role of STAT6-induced Th2 response in determining the outcome of experimental toxocariasis caused by embryonated eggs of the helminth parasite Toxocara canis. Following T. canis infection wild-type BALB/c mice developed a strong Th2-like response, produced high levels of IgG1, IgE, and IL-4, recruited alternatively activated macrophages, and displayed a moderate pathology in the lungs; however, they harbored heavy parasite loads in different tissues. In contrast, similarly infected STAT6−/− BALB/c mice mounted a weak Th2-like response, did not recruit alternatively activated macrophages, displayed a severe pathology in the lungs, but efficiently controlled T. canis infection. These findings demonstrate that Th2-like response induced via STAT6-mediated signaling pathway mediates susceptibility to larval stage of T. canis. Furthermore, they also indicate that unlike most gastrointestinal helminths, immunity against larvae of T. canis is not mediated by a Th2-dominant response. PMID:23509764

  8. Involvement of Syk kinase in TNF-induced nitric oxide production by airway epithelial cells

    International Nuclear Information System (INIS)

    Ulanova, Marina; Marcet-Palacios, Marcelo; Munoz, Samira; Asfaha, Samuel; Kim, Moo-Kyung; Schreiber, Alan D.; Befus, A. Dean

    2006-01-01

    We have recently found that Syk is widely expressed in lung epithelial cells (EC) and participates in β1 integrin signaling. In this study, we assessed the role of Syk in regulation of NO production. Stimulation of human bronchial EC line HS-24 by TNF caused an increased expression of inducible nitric oxide synthase (iNOS). Inhibition of Syk using siRNA or piceatannol down-regulated the iNOS expression and reduced NO production. This effect occurred in EC simultaneously stimulated via β1 integrins, suggesting that TNF and β1 integrins provide co-stimulatory signals. Inhibition of Syk down-regulated TNF-induced p38 and p44/42 MAPK phosphorylation and nuclear translocation of p65 NF-κB. Thus, TNF-induced activation of pro-inflammatory signaling in EC leading to enhanced expression of iNOS and NO production was dependent on Syk. Syk-mediated signaling regulates NO production at least partly via activating the MAPK cascade. Understanding the role of Syk in airway EC may help in developing new therapeutic tools for inflammatory lung disorders

  9. Collagen I-induced dendritic cells activation is regulated by TNF-α ...

    Indian Academy of Sciences (India)

    2015-02-04

    Feb 4, 2015 ... Boks MA, Kager-Groenland JR, Mousset CM, van Ham SM and. Ten Brinke A 2014 Inhibition of TNF receptor signaling by anti-. TNFα biologicals primes naïve CD4(+) T cells towards IL-10(+). T cells with a regulatory phenotype and function. Clin. Immunol. 151 136–145. Brand U, Bellinghausen I, Enk AH, ...

  10. Possible role of glutamine synthetase in the NO signaling response in root nodules by contributing to the antioxidant defenses

    Directory of Open Access Journals (Sweden)

    Liliana Santos Silva

    2013-09-01

    Full Text Available Nitric oxide (NO is emerging as an important regulatory player in the Rhizobium-legume symbiosis. The occurrence of NO during several steps of the symbiotic interaction suggests an important, but yet unknown, signaling role of this molecule for root nodule formation and functioning. The identification of the molecular targets of NO is key for the assembly of the signal transduction cascade that will ultimately help to unravel NO function. We have recently shown that the key nitrogen assimilatory enzyme Glutamine Synthetase (GS is a molecular target of NO in root nodules of Medicago truncatula, being post-translationally regulated by tyrosine nitration in relation to nitrogen fixation. In functional nodules of M. truncatula NO formation has been located in the bacteroid containing cells of the fixation zone, where the ammonium generated by bacterial nitrogenase is released to the plant cytosol and assimilated into the organic pools by plant GS. We propose that the NO-mediated GS post-translational inactivation is connected to nitrogenase inhibition induced by NO and is related to metabolite channeling to boost the nodule antioxidant defenses. Glutamate, a substrate for GS activity is also the precursor for the synthesis of glutathione (GSH, which is highly abundant in root nodules of several plant species and known to play a major role in the antioxidant defense participating in the ascorbate/GSH cycle. Existing evidence suggests that upon NO-mediated GS inhibition, glutamate could be channeled for the synthesis of GSH. According to this hypothesis, GS would be involved in the NO-signaling responses in root nodules and the NO-signaling events would meet the nodule metabolic pathways to provide an adaptive response to the inhibition of symbiotic nitrogen fixation by reactive nitrogen species (RNS.

  11. Decreased SAP expression in T cells from patients with SLE contributes to early signaling abnormalities and reduced IL-2 production

    Science.gov (United States)

    Karampetsou, Maria P.; Comte, Denis; Kis-Toth, Katalin; Terhorst, Cox; Kyttaris, Vasileios C.; Tsokos, George C.

    2016-01-01

    T cells from patients with systemic lupus erythematosus (SLE) display a number of functions including increased early signaling events following engagement of the T cell receptor (TCR). Signaling lymphocytic activation molecule family (SLAMF) cell surface receptors and the X-chromosome-defined signaling lymphocytic activation molecule-associated protein (SAP) adaptor are important in the development of several immunocyte lineages and modulating immune response. Here we present evidence that SAP protein levels are decreased in T cells and in their main subsets isolated from 32 women and 3 men with SLE independently of disease activity. In SLE T cells the SAP protein is also subject to increased degradation by a caspase-3. Forced expression of SAP in SLE T cells simultaneously heightened IL-2 production, calcium (Ca2+) responses and tyrosine phosphorylation of a number of proteins. Exposure of normal T cells to SLE serum IgG, known to contain anti-CD3/TCR antibodies, resulted in SAP downregulation. We conclude that SLE T cells display reduced levels of the adaptor protein SAP probably as a result of continuous T cell activation and degradation by caspase-3. Restoration of SAP levels in SLE T cells corrects the overexcitable lupus T cell phenotype. PMID:27183584

  12. Contribution to automatic speech recognition. Analysis of the direct acoustical signal. Recognition of isolated words and phoneme identification

    International Nuclear Information System (INIS)

    Dupeyrat, Benoit

    1981-01-01

    This report deals with the acoustical-phonetic step of the automatic recognition of the speech. The parameters used are the extrema of the acoustical signal (coded in amplitude and duration). This coding method, the properties of which are described, is simple and well adapted to a digital processing. The quality and the intelligibility of the coded signal after reconstruction are particularly satisfactory. An experiment for the automatic recognition of isolated words has been carried using this coding system. We have designed a filtering algorithm operating on the parameters of the coding. Thus the characteristics of the formants can be derived under certain conditions which are discussed. Using these characteristics the identification of a large part of the phonemes for a given speaker was achieved. Carrying on the studies has required the development of a particular methodology of real time processing which allowed immediate evaluation of the improvement of the programs. Such processing on temporal coding of the acoustical signal is extremely powerful and could represent, used in connection with other methods an efficient tool for the automatic processing of the speech.(author) [fr

  13. Contribution of rpfB to cell-to-cell signal synthesis, virulence, and vector transmission of Xylella fastidiosa.

    Science.gov (United States)

    Almeida, Rodrigo P P; Killiny, Nabil; Newman, Karyn L; Chatterjee, Subhadeep; Ionescu, Michael; Lindow, Steven E

    2012-04-01

    In Xylella fastidiosa the fatty acid signal molecule diffusible signaling factor (DSF) is produced and sensed by components of the regulation of pathogenicity factors (rpf) cluster; lack of DSF production in RpfF mutants results in a non-vector-transmissible phenotype yet cells are hypervirulent to grape. rpfB has not been characterized in Xylella fastidiosa, although its homolog has been suggested to be required for DSF synthesis in Xanthomonas campestris pv. campestris. We show that RpfB is involved in DSF processing in both Xylella fastidiosa and Xanthomonas campestris, affecting the profile of DSF-like fatty acids observed in thin-layer chromatography. Although three fatty acids whose production is dependent on RpfF were detected in Xylella fastidiosa and Xanthomonas campestris wild-type strains, their respective rpfB mutants accumulated primarily one chemical species. Although no quantifiable effect of rpfB on plant colonization by Xylella fastidiosa was found, insect colonization and transmission was reduced. Thus, RpfB apparently is involved in DSF processing, and like Xanthomonas campestris, Xylella fastidiosa also produces multiple DSF molecules. It is possible that Xylella fastidiosa coordinates host vector and plant colonization by varying the proportions of different forms of DSF signals via RpfB.

  14. Fiber type specific expression of TNF-alpha, IL-6 and IL-18 in human skeletal muscles

    DEFF Research Database (Denmark)

    Plomgaard, Peter; Penkowa, Milena; Pedersen, Bente K

    2005-01-01

    Skeletal muscle is now recognized as an endocrine organ with the capacity to produce signal peptides in response to muscle contractions. Here we demonstrate that resting healthy human muscles express cytokines in a fiber type specific manner. Human muscle biopsies from seven healthy young males...... were obtained from m. triceps, m. quadriceps vastus lateralis and m. soleus. Type I fibers contributed (mean +/- SE) 24.0 +/- 2.5% in triceps of total fibers, 51.3 +/- 2.4% in vastus and 84.9 +/- 22% in soleus. As expected, differences in the fiber type composition were accompanied by marked...... differences between the three muscles with regard to MHC I and MHC IIa mRNA expression. Immunohistochemistry demonstrated that tumor necrosis factor (TNF)-alpha and interleukin (IL)-18 were solely expressed by type II fibers, whereas the expression of IL-6 was more prominent in type I compared to type II...

  15. Inflammatory cytokine TNF-α promotes corneal endothelium apoptosis via upregulating TIPE2 transcription during corneal graft rejection.

    Science.gov (United States)

    Wang, Qun; Wei, Chao; Ma, Li; Wang, Xin; Li, Lin; Zhou, Qingjun; Shi, Weiyun

    2018-02-26

    Endothelial dysfunction accounts for 50% of total corneal transplantation failures, suggesting that corneal endothelial damage is the leading cause of graft failure. Tumor necrosis factor-α (TNF-α) is known to contribute to the negative regulation of corneal transplantation, but how it does so remains unclear. Here, we report a regulatory loop involving TNF-α, TNF-α-induced protein 8 like 2 (TNFAIP8L2 or TIPE2), and apoptosis during corneal graft rejection. We established mice models of penetrating keratoplasty to verify whether the quantification of TNF-α in allogeneic corneas is enhanced through ELISA assay and immunofluorescence staining. In cornea tissues, we obtained corneal endothelium and measured apoptosis of the removed cells. Meanwhile, quantitative real-time PCR and Western blotting were used to detect the mRNA and protein expression of TIPE2. In human corneal endothelial cells, we verified the conclusions through some experiments. By specifically knocking down TIPE2, we detected the importance of TIPE2 in TNF-α-triggered apoptosis. In mice models, TNF-α was higher in the cornea and aqueous humor in allograft group and TNF-α elevation increased the apoptosis of the corneal endothelium. In addition, high levels of TIPE2 were found in allograft rejection models following TNF-α elevation. In human corneal endothelial cells (HCECs), TNF-α clearly augments TIPE2 expression and promotes cell apoptosis through upregulating TIPE2 transcription. Knocking down markedly decreased cell apoptosis. Our study identifies the molecular mechanisms underlying the interplay of TNF-α, TIPE2, and apoptosis during allograft rejection, and it suggests that both TNF-α and TIPE2 might be potential targets for the successfully grafted corneal endothelium.

  16. TNF suppresses acute intestinal inflammation by inducing local glucocorticoid synthesis

    Science.gov (United States)

    Noti, Mario; Corazza, Nadia; Mueller, Christoph; Berger, Barbara

    2010-01-01

    Although tumor necrosis factor (α) (TNF) exerts proinflammatory activities in a variety of diseases, including inflammatory bowel disease, there is increasing evidence for antiinflammatory actions of TNF. In contrast, glucocorticoids (GCs) are steroid hormones that suppress inflammation, at least in part by regulating the expression and action of TNF. We report that TNF induces extraadrenal production of immunoregulatory GCs in the intestinal mucosa during acute intestinal inflammation. The absence of TNF results in a lack of colonic GC synthesis and exacerbation of dextran sodium sulfate–induced colitis. TNF seems to promote local steroidogenesis by directly inducing steroidogenic enzymes in intestinal epithelial cells. Therapeutic administration of TNF induces GC synthesis in oxazolone-induced colitis and ameliorates intestinal inflammation, whereas inhibition of intestinal GC synthesis abrogates the therapeutic effect of TNF. These data show that TNF suppresses the pathogenesis of acute intestinal inflammation by promoting local steroidogenesis. PMID:20439544

  17. The Role of Interleukin-6/GP130 Signaling in Prostate Cancer Progression and its Contribution to Bone Metastasis Morbidity

    Science.gov (United States)

    2008-11-01

    Those that can initiate signaling via gp130 include IL-6, IL-11, LIF, CT-1, CNTF and OSM (Heinrich et al., 1998). Notably, BM18 tumors of all...gp130 and STAT3, e.g. IL-11, LIF, CT-1, CNTF or OSM. 2c) Measure apoptosis and cellular proliferation in formalin fixed paraffin embedded BM18 xenograft...Pellegrini, S., et al. (1994). Association and activation of Jak-Tyk kinases by CNTF -LIF-OSM-IL-6 beta receptor components. Science (New York, NY 263

  18. Tumour necrosis factor-alpha (TNF), lymphotoxin and TNF receptor levels in serum from patients with Wegener's granulomatosis

    DEFF Research Database (Denmark)

    Jónasdóttir, O; Petersen, J; Bendtzen, K

    2001-01-01

    Wegener's granulomatosis (WG) is a systemic inflammatory disease with vasculitis as the key feature. Abnormal expression of tumour necrosis factor alpha (TNFalpha) is considered of prime pathogenic importance in several inflammatory diseases. The effects of TNFa are mediated by TNF receptors (TNF......-R), and these receptors are often found in soluble forms (sTNF-R), which can modulate TNFalpha actions. To evaluate the clinical importance of the TNF family of cytokines, the serum levels of TNFalpha, TNFbeta, now termed lymphotoxin (LTalpha), and sTNF-R1 and sTNF-R2 were measured by ELISA in 8 patients with WG during...... of the relative amounts of TNFalpha and sTNF-R indicated that TNFalpha was mostly bound to its soluble receptors. In WG, the serum levels of sTNF-R1 and sTNF-R2 were dramatically increased (p...

  19. The trophic effect of ouabain on retinal ganglion cells is mediated by IL-1β and TNF

    International Nuclear Information System (INIS)

    Salles von-Held-Ventura, Juliana; Mázala-de-Oliveira, Thalita; Cândida da Rocha Oliveira, Amanda; Granja, Marcelo Gomes; Gonçalves-de-Albuquerque, Cassiano Felippe; Castro-Faria-Neto, Hugo Caire; Giestal-de-Araujo, Elizabeth

    2016-01-01

    Ouabain is a steroid hormone that binds to the enzyme Na + , K + – ATPase and stimulates different intracellular pathways controlling growth, proliferation and cell survival. IL-1β and TNF-α are pleiotropic molecules, conventionally regarded as pro-inflammatory cytokines with well-known effects in the immune system. In addition, IL-1β and TNF-α also play important roles in the nervous system including neuroprotective effects. Previous data from our group showed that ouabain treatment is able to induce an increase in retinal ganglion cell survival kept in mixed retinal cell cultures. The aim of this work was to investigate if IL-1β and TNF-α could be mediating the trophic effect of ouabain on retinal ganglion cells. Our results show that the trophic effect of ouabain on retinal ganglion cell was inhibited by either anti-IL-1β or anti-TNF-α antibodies. In agreement, IL-1β or TNF-α increased the retinal ganglion cells survival in a dose-dependent manner. Accordingly, ouabain treatment induces a temporal release of TNF-α and IL-1β from retinal cell cultures. Interestingly, TNF-α and IL-1β regulate each other intracellular levels. Our results suggest that ouabain treatment triggers the activation of TNF-α and IL-1β signaling pathways leading to an increase in retinal ganglion cell survival. - Highlights: • Pro-inflammatory cytokines regulates the ouabain effect on RGC survival. • Ouabain treatment modulates the intracellular levels of TNF-α and IL-1β. • Ouabain induces the release of TNF-α and IL-1β in retinal cell cultures.

  20. The trophic effect of ouabain on retinal ganglion cells is mediated by IL-1β and TNF

    Energy Technology Data Exchange (ETDEWEB)

    Salles von-Held-Ventura, Juliana; Mázala-de-Oliveira, Thalita; Cândida da Rocha Oliveira, Amanda; Granja, Marcelo Gomes [Departamento de Neurobiologia, Programa de Neurociências, Outeiro de São João Batista s/n CEP: 24020-150, Universidade Federal Fluminense, Niterói, RJ (Brazil); Gonçalves-de-Albuquerque, Cassiano Felippe; Castro-Faria-Neto, Hugo Caire [Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Departamento de Fisiologia e Farmacodinâmica, Av., no 4365, Manguinhos, 21045-900, Rio de Janeiro, RJ (Brazil); Giestal-de-Araujo, Elizabeth, E-mail: egiestal@vm.uff.br [Departamento de Neurobiologia, Programa de Neurociências, Outeiro de São João Batista s/n CEP: 24020-150, Universidade Federal Fluminense, Niterói, RJ (Brazil)

    2016-09-09

    Ouabain is a steroid hormone that binds to the enzyme Na{sup +}, K{sup +} – ATPase and stimulates different intracellular pathways controlling growth, proliferation and cell survival. IL-1β and TNF-α are pleiotropic molecules, conventionally regarded as pro-inflammatory cytokines with well-known effects in the immune system. In addition, IL-1β and TNF-α also play important roles in the nervous system including neuroprotective effects. Previous data from our group showed that ouabain treatment is able to induce an increase in retinal ganglion cell survival kept in mixed retinal cell cultures. The aim of this work was to investigate if IL-1β and TNF-α could be mediating the trophic effect of ouabain on retinal ganglion cells. Our results show that the trophic effect of ouabain on retinal ganglion cell was inhibited by either anti-IL-1β or anti-TNF-α antibodies. In agreement, IL-1β or TNF-α increased the retinal ganglion cells survival in a dose-dependent manner. Accordingly, ouabain treatment induces a temporal release of TNF-α and IL-1β from retinal cell cultures. Interestingly, TNF-α and IL-1β regulate each other intracellular levels. Our results suggest that ouabain treatment triggers the activation of TNF-α and IL-1β signaling pathways leading to an increase in retinal ganglion cell survival. - Highlights: • Pro-inflammatory cytokines regulates the ouabain effect on RGC survival. • Ouabain treatment modulates the intracellular levels of TNF-α and IL-1β. • Ouabain induces the release of TNF-α and IL-1β in retinal cell cultures.

  1. NADPH Oxidase/ROS-Dependent VCAM-1 Induction on TNF-α-Challenged Human Cardiac Fibroblasts Enhances Monocyte Adhesion

    Science.gov (United States)

    Lin, Chih-Chung; Yang, Chien-Chung; Wang, Chen-Yu; Tseng, Hui-Ching; Pan, Chih-Shuo; Hsiao, Li-Der; Yang, Chuen-Mao

    2016-01-01

    The inflammation-dependent adhesion molecule expressions are characterized in cardiovascular diseases and myocardial tissue infiltrations. Several pro-inflammatory cytokines are elevated in the acute myocardial injury and infarction. Tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine, is raised in the injury tissues and inflammatory regions and involved in the pathogenesis of cardiac injury, inflammation, and apoptosis. In fibroblasts, TNF-α-triggered expression of vascular cell adhesion molecule (VCAM)-1 aggravated the heart inflammation. However, the mechanisms underlying TNF-α-mediated VCAM-1 expression in cardiac fibroblasts remain unclear. Here, the primary cultured human cardiac fibroblasts (HCFs) were used to investigate the effects of TNF-α on VCAM-1 expression. The molecular evidence, including protein, mRNA, and promoter analyses, indicated that TNF-α-induced VCAM-1 gene expression is mediated through the TNFR-dependent manner. Activation of TNF-α/TNFR system triggered PKCα-dependent NADPH oxidase (Nox)/reactive oxygen species (ROS) signal linking to MAPK cascades, and then led to activation of the transcription factor, AP-1. Moreover, the results of mRNA and promoter assay demonstrated that c-Jun/AP-1 phosphorylated by TNF-α turns on VCAM-1 gene expression. Subsequently, up-regulated VCAM-1 on the cell surface of TNF-α-challenged HCFs increased the number of monocytes adhering to these cells. These results indicated that in HCFs, activation of AP-1 by PKCα-dependent Nox/ROS/MAPKs cascades is required for TNF-α-induced VCAM-1 expression. To clarify the mechanisms of TNF-α-induced VCAM-1 expression in HCFs may provide therapeutic strategies for heart injury and inflammatory diseases. PMID:26858641

  2. Replication stress and oxidative damage contribute to aberrant constitutive activation of DNA damage signalling in human gliomas

    DEFF Research Database (Denmark)

    Bartkova, J; Hamerlik, P; Stockhausen, Marie

    2010-01-01

    damage signalling in low- and high-grade human gliomas, and analyze the sources of such endogenous genotoxic stress. Based on analyses of human glioblastoma multiforme (GBM) cell lines, normal astrocytes and clinical specimens from grade II astrocytomas (n=41) and grade IV GBM (n=60), we conclude...... that the DDR machinery is constitutively activated in gliomas, as documented by phosphorylated histone H2AX (gammaH2AX), activation of the ATM-Chk2-p53 pathway, 53BP1 foci and other markers. Oxidative DNA damage (8-oxoguanine) was high in some GBM cell lines and many GBM tumors, while it was low in normal...... brain and grade II astrocytomas, despite the degree of DDR activation was higher in grade II tumors. Markers indicative of ongoing DNA replication stress (Chk1 activation, Rad17 phosphorylation, replication protein A foci and single-stranded DNA) were present in GBM cells under high- or low...

  3. Contribution of IL-1RI Signaling to Protection against Cryptococcus neoformans 52D in a Mouse Model of Infection

    Directory of Open Access Journals (Sweden)

    Mitra Shourian

    2018-01-01

    Full Text Available Interleukin-1 alpha (IL-1α and interleukin-1 beta (IL-1β are pro-inflammatory cytokines that are induced after Cryptococcus neoformans infection and activate the interleukin-1 receptor type I (IL-1RI. To establish the role of IL-1RI signaling in protection against cryptococcal infection, we analyzed wild-type (WT and IL-1RI-deficient (IL-1RI−/− mice on the BALB/c background. IL-1RI−/− mice had significantly reduced survival compared to WT mice after intratracheal challenge with C. neoformans 52D. Microbiological analysis showed a significant increase in the lung and brain fungal burden of IL-1RI−/− compared to WT mice beginning at weeks 1 and 4 postinfection, respectively. Histopathology showed that IL-1RI−/− mice exhibit greater airway epithelial mucus secretion and prominent eosinophilic crystals that were absent in WT mice. Susceptibility of IL-1RI−/− mice was associated with significant induction of a Th2-biased immune response characterized by pulmonary eosinophilia, M2 macrophage polarization, and recruitment of CD4+ IL-13+ T cells. Expression of pro-inflammatory [IL-1α, IL-1β, TNFα, and monocyte chemoattractant protein 1 (MCP-1], Th1-associated (IFNγ, and Th17-associated (IL-17A cytokines was significantly reduced in IL-1RI−/− lungs compared to WT. WT mice also had higher expression of KC/CXCL1 and sustained neutrophil recruitment to the lung; however, antibody-mediated depletion of these cells showed that they were dispensable for lung fungal clearance. In conclusion, our data indicate that IL-1RI signaling is required to activate a complex series of innate and adaptive immune responses that collectively enhance host defense and survival after C. neoformans 52D infection in BALB/c mice.

  4. Fat and carbohydrate preferences in mice: the contribution of alpha-gustducin and Trpm5 taste-signaling proteins.

    Science.gov (United States)

    Sclafani, Anthony; Zukerman, Steven; Glendinning, John I; Margolskee, Robert F

    2007-10-01

    Trpm5 and alpha-gustducin are key to the transduction of tastes of sugars, amino acids, and bitter compounds. This study investigated the role of these signaling proteins in the preference for fat, starch, and starch-derived polysaccharides (Polycose), using Trpm5 knockout (Trpm5 KO) and alpha-gustducin knockout (Gust KO) mice. In initial two-bottle tests (24 h/day), Trpm5 KO mice showed no preference for soybean oil emulsions (0.313-2.5%), Polycose solutions (0.5-4%), or starch suspensions (0.5-4%). Gust KO mice displayed an attenuated preference for Polycose, but their preferences for soybean oil and starch were comparable to those of C57BL/6J wild-type (WT) mice. Gust KO mice preferred starch to Polycose, whereas WT mice had the opposite preference. After extensive experience with soybean oil emulsions (Intralipid) and Polycose solutions, the Trpm5 KO mice developed preferences comparable to the WT mice, although their absolute intakes remained suppressed. Similarly, Gust KO mice developed a strong Polycose preference with experience, but they continued to consume less than the WT mice. These results implicate alpha-gustducin and Trpm5 as mediators of polysaccharide taste and Trpm5 in fat taste. The disruption in Polycose, but not starch, preference in Gust KO mice indicates that distinct sensory signaling pathways mediate the response to these carbohydrates. The experience-induced rescue of fat and Polycose preferences in the KO mice likely reflects the action of a postoral-conditioning mechanism, which functions in the absence of alpha-gustducin and Trpm5.

  5. Rac1/β-Catenin Signalling Pathway Contributes to Trophoblast Cell Invasion by Targeting Snail and MMP9

    Directory of Open Access Journals (Sweden)

    Minghua Fan

    2016-03-01

    Full Text Available Background/Aims: Preeclampsia is an idiopathic and serious complication during gestation in which placental trophoblast cells differentiate into several functional subtypes, including highly invasive extravillous trophoblasts (EVTs. Although the cause and pathogenesis of preeclampsia have remained unclear, numerous studies have suggested that the inadequacy of EVT invasion leads to imperfect uterine spiral artery remodelling, which plays a crucial role in the development of preeclampsia. Rac1, or Ras-related C3 botulinum toxin substrate 1, was found to be a key regulator of the migration, invasion uand apoptosis of various tumour cells. Because EVTs share similar invasive and migratory biological behaviours with malignant cells, this study aimed to determine whether the Rac1 signalling pathway affects trophoblast invasion and is thus involved in the pathogenesis of preeclampsia. Methods: We measured the activity of Rac1 and its downstream targets, β-catenin, Snail and MMP9 in placental tissues from patients experiencing a normal pregnancy and those with preeclampsia. Furthermore, we treated HTR-8/SVneo cells with a shRNA Rac1 vector and the β-catenin inhibitor IWP-2 and explored Rac1 signalling pathway activation as well as the effects of Snail and β-catenin on trophoblast invasion. Results: In placental samples from patients experiencing a normal pregnancy and those with preeclampsia, active Rac1 levels and MMP9 protein and mRNA levels were significantly decreased in term pregnancy samples compared to early pregnancy samples. Lower levels were found in preeclampsia samples than in normal term pregnancy samples, and these levels significantly declined in severe preeclampsia samples compared with mild preeclampsia samples. Further analyses demonstrated that both Rac1 shRNA and the β-catenin inhibitor significantly suppressed MMP9 and Snail activation in trophoblasts, thus impairing trophoblast invasion. Notably, silencing Rac1 down

  6. Systemically administered anti-TNF therapy ameliorates functional outcomes after focal cerebral ischemia

    DEFF Research Database (Denmark)

    Clausen, Bettina Hjelm; Degn, Matilda; Martin, Nellie Anne

    2014-01-01

    BackgroundThe innate immune system contributes to the outcome after stroke, where neuroinflammation and post-stroke systemic immune depression are central features. Tumor necrosis factor (TNF), which exists in both a transmembrane (tm) and soluble (sol) form, is known to sustain complex inflammat...

  7. TNF-α blockade induces IL-10 expression in human CD4+ T cells

    NARCIS (Netherlands)

    Evans, Hayley G.; Roostalu, Urmas; Walter, Gina J.; Gullick, Nicola J.; Frederiksen, Klaus S.; Roberts, Ceri A.; Sumner, Jonathan; Baeten, Dominique L.; Gerwien, Jens G.; Cope, Andrew P.; Geissmann, Frederic; Kirkham, Bruce W.; Taams, Leonie S.

    2014-01-01

    IL-17+ CD4+ T (Th17) cells contribute to the pathogenesis of several human inflammatory diseases. Here we demonstrate that TNF inhibitor (TNFi) drugs induce the anti-inflammatory cytokine IL-10 in CD4+ T cells including IL-17+ CD4+ T cells. TNFi-mediated induction of IL-10 in IL-17+ CD4+ T cells is

  8. Anti-inflammatory effect of resveratrol on TNF-α-induced MCP-1 expression in adipocytes

    International Nuclear Information System (INIS)

    Zhu Jian; Yong Wei; Wu Xiaohong; Yu Ying; Lv Jinghuan; Liu Cuiping; Mao Xiaodong; Zhu Yunxia; Xu Kuanfeng; Han Xiao; Liu Chao

    2008-01-01

    Chronic low-grade inflammation characterized by adipose tissue macrophage accumulation and abnormal cytokine production is a key feature of obesity and type 2 diabetes. Adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, induced by cytokines, has been shown to play an essential role in the early events during macrophage infiltration into adipose tissue. In this study we investigated the effects of resveratrol upon both tumor necrosis factor (TNF)-α-induced MCP-1 gene expression and its underlying signaling pathways in 3T3-L1 adipoctyes. Resveratrol was found to inhibit TNF-α-induced MCP-1 secretion and gene transcription, as well as promoter activity, which based on down-regulation of TNF-α-induced MCP-1 transcription. Nuclear factor (NF)-κB was determined to play a major role in the TNF-α-induced MCP-1 expression. Further analysis showed that resveratrol inhibited DNA binding activity of the NF-κB complex and subsequently suppressed NF-κB transcriptional activity in TNF-α-stimulated cells. Finally, the inhibition of MCP-1 may represent a novel mechanism of resveratrol in preventing obesity-related pathologies

  9. Complications of TNF-α antagonists and iron homeostasis

    Science.gov (United States)

    TNF-α is a central regulator of inflammation and its blockade downregulates other proinflammatory cytokines, chemokines, and growth factors. Subsequently, TNF-α antagonists are currently used in treatment regimens directed toward several inflammatory diseases. Despite a beneficia...

  10. TNF-α potentiates uric acid-induced interleukin-1β (IL-1β) secretion in human neutrophils.

    Science.gov (United States)

    Yokose, Kohei; Sato, Shuzo; Asano, Tomoyuki; Yashiro, Makiko; Kobayashi, Hiroko; Watanabe, Hiroshi; Suzuki, Eiji; Sato, Chikako; Kozuru, Hideko; Yatsuhashi, Hiroshi; Migita, Kiyoshi

    2017-09-14

    Monosodium urate (MSU) has been shown to promote interleukin-1β (IL-1β) secretion in human monocytes, but the priming signals for NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway remains elusive. In this study, we investigated the role of Tumor necrosis factor-alpha (TNF-α) on MSU-mediated IL-1β induction in human neutrophils. Human neutrophils were stimulated with MSU, in the presence or absence of TNF-α priming. The cellular supernatants were analyzed for IL-1β, IL-18, and caspase-1 by enzyme-linked immunosorbent assay (ELISA) methods. Pro-IL-1β mRNA expressions in human neutrophils were analyzed by real-time PCR method. TNF-α stimulation induced pro-IL-1β mRNA expression; however, MSU stimulation did not induce pro-IL-1β mRNA expression in human neutrophils. TNF-α alone or MSU stimulation did not result in efficient IL-1β secretion in human neutrophils, whereas in TNF-α-primed neutrophils, MSU stimulation resulted in a marked IL-1β and IL-18 secretion. TNF-α-primed neutrophils secreted cleaved caspase-1 (p20), in response to MSU stimulation. Our data demonstrate that priming of human neutrophils with TNF-α promotes uric acid-mediated IL-1β secretion in the absence of microbial stimulation. These findings provide insights into the neutrophils-mediated inflammatory processes in gouty arthritis.

  11. EPA blocks TNF-α-induced inhibition of sugar uptake in Caco-2 cells via GPR120 and AMPK.

    Science.gov (United States)

    Castilla-Madrigal, Rosa; Barrenetxe, Jaione; Moreno-Aliaga, María J; Lostao, María Pilar

    2018-03-01

    The aim of the present work was to investigate in Caco-2 cells whether eicosapentaenoic acid (EPA), an omega-3 polyunsaturated fatty acid, could block the inhibitory effect of tumor necrosis factor-α (TNF-α) on sugar transport, and identify the intracellular signaling pathways involved. After pre-incubation of the Caco-2 cells with TNF-α and EPA for 1 hr, EPA prevented the inhibitory effect of the cytokine on α-methyl-d-glucose (αMG) uptake (15 min) and on SGLT1 expression at the brush border membrane, measured by Western blot. The ERK1/2 inhibitor PD98059 and the AMPK activator AICAR also prevented the inhibitory effect of TNF-α on both αMG uptake and SGLT1 expression. Interestingly, the AMPK inhibitor, Compound C, abolished the ability of EPA to prevent TNF-α-induced reduction of sugar uptake and transporter expression. The GPR120 antagonist, AH7614, also blocked the preventive effect of EPA on TNF-α-induced decrease of αMG uptake and AMPK phosphorylation. In summary, TNF-α inhibits αMG uptake by decreasing SGLT1 expression in the brush border membrane through the activation of ERK1/2 pathway. EPA prevents the inhibitory effect of TNF-α through the involvement of GPR120 and AMPK activation. © 2017 Wiley Periodicals, Inc.

  12. Redundant signaling mechanisms contribute to the vasodilatory response of the afferent arteriole to proteinase-activated receptor-2.

    Science.gov (United States)

    Wang, Xuemei; Hollenberg, Morley D; Loutzenhiser, Rodger

    2005-01-01

    We previously demonstrated that stimulation of proteinase-activated receptor-2 (PAR-2) by SLIGRL-NH(2) elicits afferent arteriolar vasodilation, in part, by elaborating nitric oxide (NO), suggesting an endothelium-dependent mechanism (Trottier G, Hollenberg M, Wang X, Gui Y, Loutzenhiser K, and Loutzenhiser R. Am J Physiol Renal Physiol 282: F891-F897, 2002). In the present study, we characterized the NO-independent component of this response, using the in vitro perfused hydronephrotic rat kidney. SLIGRL-NH(2) (10 mumol/l) dilated afferent arterioles preconstricted with ANG II, and the initial transient component of this response was resistant to NO synthase (NOS) and cyclooxygenase inhibition. This NO-independent response was not prevented by treatment with 10 nmol/l charybdotoxin and 1 mumol/l apamin, a manipulation that prevents the endothelium-derived hyperpolarizing factor (EDHF)-like response of the afferent arteriole to acetylcholine, nor was it blocked by the addition of 1 mmol/l tetraethylammonium (TEA) or 50 mumol/l 17-octadecynoic acid, treatments that block the EDHF-like response to bradykinin. To determine whether the PAR-2 response additionally involves the electrogenic Na(+)-K(+)-ATPase, responses were evaluated in the presence of 3 mmol/l ouabain. In this setting, SLIGRL-NH(2) induced a biphasic dilation in control and a transient response after NOS inhibition. The latter was not prevented by charybdotoxin plus apamin or by TEA alone but was abolished by combined treatment with charybdotoxin, apamin, and TEA. This treatment did not prevent the NO-dependent dilation evoked in the absence of NOS inhibition. Our findings indicate a remarkable redundancy in the signaling cascade mediating PAR-2 -induced afferent arteriolar vasodilation, suggesting an importance in settings such as inflamation or ischemia, in which vascular mechanisms might be impaired and the PAR system is thought to be activated.

  13. Direct effects of TNF-α on local fuel metabolism and cytokine levels in the placebo controlled bilaterally infused human leg

    DEFF Research Database (Denmark)

    Bach, Ermina; Nielsen, Bent Roni Ranghøj; Vendelbo, Mikkel

    2013-01-01

    Tumor necrosis factor-α (TNF-α) has widespread metabolic actions. Systemic TNF-α administration, however, generates a complex hormonal and metabolic response. Our study was designed to test whether regional, placebo-controlled TNF-α infusion directly affects insulin resistance and protein breakdown....... We studied eight healthy volunteers once with bilateral femoral vein and artery catheters during a 3-h basal period and a 3-h hyperinsulinemic-euglycemic clamp. One artery was perfused with saline and one with TNF-α. During the clamp, TNF-α perfusion increased glucose arteriovenous differences (0...... interest and may concurrently act to provide adequate tissue fuel supply and contribute to the occurrence of systemic hypoglycemia. This distinct metabolic feature places TNF-α among the rare insulin mimetics of human origin....

  14. Contribution of PPARγ in modulation of acrolein-induced inflammatory signaling in gp91phox knock-out mice.

    Science.gov (United States)

    Yousefipour, Zivar; Chug, Neha; Marek, Katarzyna; Nesbary, Alicia; Mathew, Joseph; Ranganna, Kasturi; Newaz, Mohammad A

    2017-08-01

    Oxidative stress and inflammation are major contributors to acrolein toxicity. Peroxisome proliferator activated receptor gamma (PPARγ) has antioxidant and anti-inflammatory effects. We investigated the contribution of PPARγ ligand GW1929 to the attenuation of oxidative stress in acrolein-induced insult. Male gp91 phox knock-out (KO) mice were treated with acrolein (0.5 mg·(kg body mass) -1 by intraperitoneal injection for 7 days) with or without GW1929 (GW; 0.5 mg·(kg body mass) -1 ·day -1 , orally, for 10 days). The livers were processed for further analyses. Acrolein significantly increased 8-isoprostane and reduced PPARγ activity (P acrolein-treated WT mice, and was reduced by GW1929 (by 65%). KO mice exhibited higher xanthine oxidase (XO). Acrolein increased XO and COX in WT mice and XO in KO mice. GW1929 significantly reduced COX in WT and KO mice and reduced XO in KO mice. Acrolein significantly reduced the total antioxidant status in WT and KO mice (P acrolein-treated WT mice. GW1929 reduced NF-κB levels (by 51%) in KO mice. Acrolein increased CD36 in KO mice (by 43%), which was blunted with GW1929. Data confirms that the generation of free radicals by acrolein is mainly through NAD(P)H, but other oxygenates play a role too. GW1929 may alleviate the toxicity of acrolein by attenuating NF-κB, COX, and CD36.

  15. Taming TNF : strategies to restrain this proinflammatory cytokine

    NARCIS (Netherlands)

    Eigler, A; Sinha, B; Hartmann, G; Endres, S

    1997-01-01

    Recent studies have demonstrated the essential role of tumor necrosis factor alpha (TNF-alpha) in rheumatoid arthritis and Crohn's disease. This article discusses agents known to suppress the formation or activity of TNF-alpha, and summarizes clinical studies using anti-TNF-alpha antibodies.

  16. Antibodies to a soluble form of a tumor necrosis factor (TNF) receptor have TNF-like activity

    DEFF Research Database (Denmark)

    Engelmann, H; Holtmann, H; Brakebusch, C

    1990-01-01

    Immunological cross-reactivity between tumor necrosis factor (TNF) binding proteins which are present in human urine (designated TBPI and TBPII) and two molecular species of the cell surface receptors for TNF is demonstrated. The two TNF receptors are shown to be immunologically distinct, to differ...... in molecular weight (58,000 and 73,000), and to be expressed differentially in different cells. It is further shown that polyclonal antibodies against one of the TNF binding proteins (TBPI) display, by virtue of their ability to bind the TNF receptor, activities which are very similar to those of TNF....... These antibodies are cytotoxic to cells which are sensitive to TNF toxicity, induce resistance to TNF toxicity, enhance the incorporation of thymidine into normal fibroblasts, inhibit the growth of chlamydiae, and induce the synthesis of prostaglandin E2. Monovalent F(ab) fragments of the polyclonal antibodies...

  17. cAMP/PKA signaling pathway contributes to neuronal apoptosis via regulating IDE expression in a mixed model of type 2 diabetes and Alzheimer's disease.

    Science.gov (United States)

    Li, Huajie; Yang, Song; Wu, Jian; Ji, Lei; Zhu, Linfeng; Cao, Liping; Huang, Jinzhong; Jiang, Qingqing; Wei, Jiang; Liu, Meng; Mao, Keshi; Wei, Ning; Xie, Wei; Yang, Zhilong

    2018-02-01

    Type 2 diabetes (T2D) may play a relevant role in the development of Alzheimer's disease (AD), however, the underlying mechanism was not clear yet. We developed an animal model presenting both AD and T2D, morris water maze (MWM) test and recognition task were performed to trace the cognitive function. Fasting plasma glucose (FPG) and oral glucose tolerance test (OGTT) were determined to trace the metabolism evolution. TUNEL assay and apoptosis-related protein levels were analyzed for the detection of neuronal apoptosis. Cyclic adenosine monophosphate (cAMP) agonist bucladesine or protein kinase (PKA) inhibitor H-89 were used to determine the effects of cAMP/PKA signaling pathway on IDE expression and neuronal apoptosis. The results showed that T2D contributes to the AD progress by accelerating and worsening spatial memory and recognition dysfunctions. Metabolic parameters and glucose tolerance were significantly changed in the presence of the AD and T2D. The significantly induced neuronal apoptosis and increased pro-apoptotic proteins in mice with AD and T2D were also observed. We showed the decreased expression level of IDE and the activating of cAMP/PKA signaling pathway in AD and T2D mice. Further studies indicated that cAMP agonist decreased the expression level of IDE and induced the neuronal apoptosis in mice with AD and T2D; whereas PKA inhibitor H-89 treatment showed the completely opposite results. Our study indicated that, in the T2D and AD mice, cAMP/PKA signaling pathway and IDE may participate in the contribute role of T2D in accelerating the pathological process of AD via causing the accumulation of Aβ and neuronal apoptosis. © 2017 Wiley Periodicals, Inc.

  18. Signal peptidase complex 18, encoded by SEC11A, contributes to progression via TGF-α secretion in gastric cancer.

    Science.gov (United States)

    Oue, N; Naito, Y; Hayashi, T; Takigahira, M; Kawano-Nagatsuma, A; Sentani, K; Sakamoto, N; Zarni Oo, H; Uraoka, N; Yanagihara, K; Ochiai, A; Sasaki, H; Yasui, W

    2014-07-24

    We built an in-house oligonucleotide array on which 394 genes were selected based on our Serial Analysis of Gene Expression (SAGE) data and previously reported array data and listed several genes related to cancer progression. Among these, we focused on SEC11A, which encodes the SPC18 protein. SEC11A mRNA expression was measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in gastric cancer (GC) tissue samples. Expression and distribution of SPC18 protein were investigated by immunohistochemical analysis in two independent GC cohorts (Hiroshima cohort, n=99 and Chiba cohort, n=989). To determine the effect of SPC18 on cell viability and invasiveness in vitro, MTT and Boyden chamber invasion assays were performed. To evaluate the influence of SPC18 on cell growth in vivo, GC cells were injected into severe combined immunodeficiency mice. Levels of TGF-α and EGF in media from the GC cells were measured by enzyme-linked immunosorbent assay (ELISA). Studies in human tissue revealed overexpression of SEC11A mRNA in 40% of 42 GC samples by qRT-PCR. Immunohistochemical analysis of SPC18 revealed that 26 and 20% of GC cases were SPC18-positive in the Hiroshima and Chiba cohorts, respectively. In both cohorts, the Kaplan-Meier analysis showed poorer survival in SPC18-positive GC cases than in SPC18-negative GC cases. Forced expression of SPC18 activates GC cell growth in vitro and in vivo. The levels of TGF-α in culture media from GC cells were reduced by knockdown of SPC18. These results indicate that SPC18 contributes to malignant progression through promotion of TGF-α secretion in GC.

  19. Effects of TNF-α blocking on experimental periodontitis and type 2 diabetes in obese diabetic Zucker rats

    DEFF Research Database (Denmark)

    Grauballe, Morten Christian Bay; Østergaard, Jakob Appel; Schou, Søren

    2015-01-01

    OBJECTIVE: Tumour necrosis factor α (TNF-α) is considered a key signalling modulator in the pathogenesis of both periodontitis (PD) and type 2 diabetes mellitus (DM2). This study aims at elucidating the effect of TNF-α blocking on the interplay between PD and DM2. METHODS: Obese diabetic Zucker...... rats and their lean littermates were divided into five treatment groups with or without periodontitis. Anti-TNF-α treatment was provided with Etanercept injections. Diabetic state was evaluated by oral glucose tolerance test, the homeostatic model assessment, free fatty acids and blood glucose...... treatment. CONCLUSION: In this study anti-TNF-α treatment improved glucose tolerance and compensated for the increased periodontal disease in obese diabetic Zucker. PD did not influence diabetic parameters assessed including complications of the rats kidneys....

  20. Sporothrix schenckii yeasts induce ERK pathway activation and secretion of IL-6 and TNF-α in rat mast cells, but no degranulation.

    Science.gov (United States)

    Romo-Lozano, Yolanda; Hernández-Hernández, Francisca; Salinas, Eva

    2014-11-01

    Sporothrix schenckii is a dimorphic fungus that causes sporotrichosis, a subcutaneous mycosis found throughout the world in humans and other mammals. After contact with conidia, transition to the yeast stage is required for establishment of infection. Mast cells are one of the first components of the immune system to make contact with invading pathogens. They release potent mediators that are decisive in initiating and directing the course of immune and inflammatory responses in the host. It remains unknown whether or not yeast cells of S. schenckii activate mast cells. Our aim in this study was to evaluate the in vitro response of mast cells to S. schenckii yeasts cells. Mast cells became activated after interaction with the yeasts, although exocytosis of preformed mediators was not stimulated. Sporothrix schenckii yeasts induced the release of early response cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6 and activation of the extracellular signal-regulated kinase (ERK) signaling pathway in mast cells. As TNF-α and IL-6 are considered crucial mediators in the defense of the host against fungal disease, the release of both mediators from mast cells may contribute to the overall response of the host immune system during S. schenckii infection. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Functional connectivity in the dorsal stream and between bilateral auditory-related cortical areas differentially contribute to speech decoding depending on spectro-temporal signal integrity and performance.

    Science.gov (United States)

    Elmer, Stefan; Kühnis, Jürg; Rauch, Piyush; Abolfazl Valizadeh, Seyed; Jäncke, Lutz

    2017-11-01

    Speech processing relies on the interdependence between auditory perception, sensorimotor integration, and verbal memory functions. Functional and structural connectivity between bilateral auditory-related cortical areas (ARCAs) facilitates spectro-temporal analyses, whereas the dynamic interplay between ARCAs and Broca's area (i.e., dorsal pathway) contributes to verbal memory functions, articulation, and sound-to-motor mapping. However, it remains unclear whether these two neural circuits are preferentially driven by spectral or temporal acoustic information, and whether their recruitment is predictive of speech perception performance and learning. Therefore, we evaluated EEG-based intracranial (eLORETA) functional connectivity (lagged coherence) in both pathways (i.e., between bilateral ARCAs and in the dorsal stream) while good- (GPs, N = 12) and poor performers (PPs, N = 13) learned to decode natural pseudowords (CLEAN) or comparable items (speech-noise chimeras) manipulated in the envelope (ENV) or in the fine-structure (FS). Learning to decode degraded speech was generally associated with increased functional connectivity in the theta, alpha, and beta frequency range in both circuits. Furthermore, GPs exhibited increased connectivity in the left dorsal stream compared to PPs, but only during the FS condition and in the theta frequency band. These results suggest that both pathways contribute to the decoding of spectro-temporal degraded speech by increasing the communication between brain regions involved in perceptual analyses and verbal memory functions. Otherwise, the left-hemispheric recruitment of the dorsal stream in GPs during the FS condition points to a contribution of this pathway to articulatory-based memory processes that are dependent on the temporal integrity of the speech signal. These results enable to better comprehend the neural circuits underlying word-learning as a function of temporal and spectral signal integrity and performance

  2. Sex Differences of Human Cardiac Progenitor Cells in the Biological Response to TNF-α Treatment

    Directory of Open Access Journals (Sweden)

    Elisabetta Straface

    2017-01-01

    Full Text Available Adult cardiac progenitor cells (CPCs, isolated as cardiosphere-derived cells (CDCs, represent promising candidates for cardiac regenerative therapy. CDCs can be expanded in vitro manyfolds without losing their differentiation potential, reaching numbers that are appropriate for clinical applications. Since mechanisms of successful CDC survival and engraftment in the damaged myocardium are still critical and unresolved issues, we aimed at deciphering possible key factors capable of bolstering CDC function. In particular, the response and the phenotype of CDCs exposed to low concentrations of the multifunctional cytokine tumor necrosis factor α (TNF-α, known to be capable of activating cell survival pathways, have been investigated. Furthermore, differential biological responses of CDCs from male and female donors, in terms of cell cycle progression and cell spreading, have also been assessed. The results obtained indicate that (i the intracellular signaling activated in our experimental conditions is most likely due to the prosurvival and proliferative signaling of TNF-α receptor 2 and that (ii cells from female patients appear more responsive to TNF-α treatment in terms of cell cycle progression and migration ability. In conclusion, the present report highlights the hypothesis that TNF-stimulated CDCs isolated from females may represent a promising candidate for cardiac regenerative therapy applications.

  3. Blimp-1-Dependent IL-10 Production by Tr1 Cells Regulates TNF-Mediated Tissue Pathology.

    Directory of Open Access Journals (Sweden)

    Marcela Montes de Oca

    2016-01-01

    Full Text Available Tumor necrosis factor (TNF is critical for controlling many intracellular infections, but can also contribute to inflammation. It can promote the destruction of important cell populations and trigger dramatic tissue remodeling following establishment of chronic disease. Therefore, a better understanding of TNF regulation is needed to allow pathogen control without causing or exacerbating disease. IL-10 is an important regulatory cytokine with broad activities, including the suppression of inflammation. IL-10 is produced by different immune cells; however, its regulation and function appears to be cell-specific and context-dependent. Recently, IL-10 produced by Th1 (Tr1 cells was shown to protect host tissues from inflammation induced following infection. Here, we identify a novel pathway of TNF regulation by IL-10 from Tr1 cells during parasitic infection. We report elevated Blimp-1 mRNA levels in CD4+ T cells from visceral leishmaniasis (VL patients, and demonstrate IL-12 was essential for Blimp-1 expression and Tr1 cell development in experimental VL. Critically, we show Blimp-1-dependent IL-10 production by Tr1 cells prevents tissue damage caused by IFNγ-dependent TNF production. Therefore, we identify Blimp-1-dependent IL-10 produced by Tr1 cells as a key regulator of TNF-mediated pathology and identify Tr1 cells as potential therapeutic tools to control inflammation.

  4. Association of the TNF-alpha G-308A polymorphism with TNF-inhibitor response in sarcoidosis

    NARCIS (Netherlands)

    Wijnen, P.A.; Cremers, J.P.; Nelemans, P.J.; Erckens, R.J.; Hoitsma, E.; Jansen, T.L.; Bekers, O.; Drent, M.

    2014-01-01

    Responsiveness to tumour necrosis factor (TNF) inhibitors has been associated with the TNF-alpha G-308A polymorphism in rheumatoid arthritis. The aim of this study was to examine the association between the presence of this polymorphism and the response to TNF inhibitors in patients with refractory

  5. Relation of serum TNF-α and TNF-α genotype with delayed cerebral ischemia and outcome in subarachnoid hemorrhage

    NARCIS (Netherlands)

    Beeftink, Martine M. A.; Ruigrok, Ynte M.; Rinkel, Gabriel J. E.; van den Bergh, Walter M.

    2011-01-01

    The pathogenesis of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) remains obscure. The authors assessed the relationship of tumor necrosis factor alpha (TNF-α) and TNF-α gene polymorphisms with occurrence of DCI and poor outcome at 3 months. Serum levels of TNF-α were measured

  6. Antibodies to a soluble form of a tumor necrosis factor (TNF) receptor have TNF-like activity

    DEFF Research Database (Denmark)

    Engelmann, H; Holtmann, H; Brakebusch, C

    1990-01-01

    lack TNF-like activities, but acquire them upon cross-linking with anti-F(ab)2 antibodies, suggesting that the ability of the anti-TBPI antibodies to mimic TNF correlates with their ability to cross-link the TNF receptors. This notion was further supported by data obtained in a comparative study...

  7. Impact of anti-TNF therapy on NK cells function and on immunosurveillance against B-cell lymphomas.

    Science.gov (United States)

    Nocturne, Gaetane; Boudaoud, Saida; Ly, Bineta; Pascaud, Juliette; Paoletti, Audrey; Mariette, Xavier

    2017-06-01

    Rheumatoid arthritis (RA) is associated with an increased risk of lymphoma linked to activity of the disease. Immunosuppressive drugs have been suspected to induce an additional risk. Since, NK cells have been recently shown to participate to anti-lymphoma immunosurveillance, we aimed to assess if anti-TNF might impact their anti-lymphoma activity. NK cells have been assessed ex vivo in patients with RA treated with methotrexate (MTX) with or without anti-TNF. Phenotype has been studied by flow cytometry and function has been assessed after NKp30-cross linking. NK have been cultured 6 days in presence of anti-TNF, TNF-R inhibitors or controls and phenotype has been studied. Then cytotoxicity against 2 B non-Hodgkin lymphoma cell lines [Farage (EBV+) and SU-DHL4 (EBV-)] was assessed. Exposure to anti-TNF was associated with a decreased activation of NK cells. NK cells exhibited an impaired function in patients treated with anti-TNF compared to patients treated with MTX alone as assessed by the percentage of degranulation (20.9% [18.5-32.9] vs 31.3% [21.5-49.1], p = 0.04) and a decreased IFN-γ secretion ((17.4% [8.9-25.9] vs to 29.7% [22.5-43.1], p = 0.007). In vitro, exposure to anti-TNF impaired NK cells function and impacted negatively anti-lymphoma activity. These effects may be the consequence of inhibition of TNFR1 signaling. Thus, even if meta-analysis of randomized controlled trials and of registries have not demonstrated to date an increased risk of lymphoma with anti-TNF, cautious must be pursued concerning this possible side effect in patients with long-term anti-TNF exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Benzimidazoles Promote Anti-TNF Mediated Induction of Regulatory Macrophages and Enhance Therapeutic Efficacy in a Murine Model.

    Science.gov (United States)

    Wildenberg, Manon E; Levin, Alon D; Ceroni, Alessandro; Guo, Zhen; Koelink, Pim J; Hakvoort, Theodorus B M; Westera, Liset; Bloemendaal, Felicia M; Brandse, Johannan F; Simmons, Alison; D'Haens, Geert R; Ebner, Daniel; van den Brink, Gijs R

    2017-12-04

    Regulatory macrophages play a critical role in tissue repair, and we have previously shown that anti-tumour necrosis factor [TNF] antibodies induce these macrophages in vitro and in vivo in IBD patients. The induction of regulatory macrophages can be potentiated using the combination of anti-TNF and thiopurines, consistent with the enhanced efficacy of this combination therapy described in clinical trials. As thiopurines are unfortunately associated with significant side effects, we here aimed to identify alternatives for combination therapy with anti-TNF, using the macrophage induction model as a screening tool. Mixed lymphocyte reactions were treated with anti-TNF and a library of 1600 drug compounds. Induction of CD14+CD206+ macrophages was analysed by flow cytometry. Positive hits were validated in vitro and in the T cell transfer model of colitis. Among the 98 compounds potentiating the induction of regulatory macrophages by anti-TNF were six benzimidazoles, including albendazole. Albendazole treatment in the presence of anti-TNF resulted in alterations in the tubulin skeleton and signalling though AMPK, which was required for the enhanced induction. Combination therapy also increased expression levels of the immunoregulatory cytokine IL-10. In vivo, albendazole plus anti-TNF combination therapy was superior to monotherapy in a model of colitis, in terms of both induction of regulatory macrophages and improvement of clinical symptoms. Albendazole enhances the induction of regulatory macrophages by anti-TNF and potentiates clinical efficacy in murine colitis. Given its favourable safety profile, these data indicate that the repurposing of albendazole may be a novel option for anti-TNF combination therapy in IBD.

  9. TNF-α exerts cytotoxic effects on multidrug resistant breast cancer MCF-7/MX cells via a non-apoptotic death pathway.

    Science.gov (United States)

    Ghandadi, Morteza; Behravan, Javad; Abnous, Khalil; Ehtesham Gharaee, Melika; Mosaffa, Fatemeh

    2017-09-01

    Tumor necrosis factor-α (TNF-α) is a cytokine involved in the various physiopathological processes such as autoimmune disorders and inflammation related diseases. Some multidrug resistant (MDR) cancer cell lines including MCF-7/MX are more vulnerable to cytotoxic effects of TNF-α than their parental lines. In this study, breast cancer cell line MCF-7 and its MDR derivative MCF-7/MX were exposed to TNF-α afterward various downstream signaling mediators of TNF-α were analyzed. Although, treatment of MCF-7 cells with TNF-α activated NF-kB and caused RIP1 ubiquitination, TNF-α exposure led to JNK and RIP1 phosphorylation in MCF-7/MX cells. In both cell lines TNF-α did not activate the caspase cascade. Moreover, AnexinV/PI analysis showed that cytotoxic effects of TNF-α on MCF-7/MX is mediated via apoptosis independent mechanisms and inhibition of RIP1 kinase activity using necrostatin-1 revealed that kinase activity of RIP1 plays role in the production of ROS, activation of JNK and cellular death following exposure of MCF-7/MX cells to TNF-α. Overall, it seems that RIP1 ubiquitination and NF-kB activation are prosurvival signaling mediators protecting MCF-7 cells against cytotoxic effects of TNF-α while TNF-α drives MCF-7/MX cells to non-apoptotic cellular death via kinase activity of RIP1, activation of JNK and ROS production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Curcumin: an orally bioavailable blocker of TNF and other pro-inflammatory biomarkers

    Science.gov (United States)

    Aggarwal, Bharat B; Gupta, Subash C; Sung, Bokyung

    2013-01-01

    TNFs are major mediators of inflammation and inflammation-related diseases, hence, the United States Food and Drug Administration (FDA) has approved the use of blockers of the cytokine, TNF-α, for the treatment of osteoarthritis, inflammatory bowel disease, psoriasis and ankylosis. These drugs include the chimeric TNF antibody (infliximab), humanized TNF-α antibody (Humira) and soluble TNF receptor-II (Enbrel) and are associated with a total cumulative market value of more than $20 billion a year. As well as being expensive ($15 000–20 000 per person per year), these drugs have to be injected and have enough adverse effects to be given a black label warning by the FDA. In the current report, we describe an alternative, curcumin (diferuloylmethane), a component of turmeric (Curcuma longa) that is very inexpensive, orally bioavailable and highly safe in humans, yet can block TNF-α action and production in in vitro models, in animal models and in humans. In addition, we provide evidence for curcumin's activities against all of the diseases for which TNF blockers are currently being used. Mechanisms by which curcumin inhibits the production and the cell signalling pathways activated by this cytokine are also discussed. With health-care costs and safety being major issues today, this golden spice may help provide the solution. Linked Articles This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8 PMID:23425071

  11. Local delivery of soluble TNF-alpha receptor 1 gene reduces infarct size following ischemia/reperfusion injury in rats.

    Science.gov (United States)

    Sugano, Masahiro; Hata, Tomoji; Tsuchida, Keiko; Suematsu, Nobuhiro; Oyama, Jun-Ichi; Satoh, Shinji; Makino, Naoki

    2004-11-01

    Apoptosis in the myocardium is linked to ischemia/reperfusion injury, and TNF-alpha induces apoptosis in cardiomyocytes. A significant amount of TNF-alpha is detected after ischemia and reperfusion. Soluble TNF-alpha receptor 1 (sTNFR1) is an extracellular domain of TNF-alpha receptor 1 and is an antagonist to TNF-alpha. In the present study, we examined the effects of sTNFR1 on infarct size in acute myocardial infarction (AMI) following ischemia/reperfusion. Male Wistar rats were subjected to left coronary artery (LCA) ligation. After 30 min of LCA occlusion, the temporary ligature on the LCA was released and blood flow was restored. Immediately after reperfusion, a total of 200 microg of sTNFR1 or LacZ plasmid was injected into three different sites of the left ventricular wall. At 6 h, 1 and 2 days after reperfusion, the TNF-alpha bioactivity in the myocardium was significantly higher in rats receiving LacZ plasmid than in sham-operated rats, whereas sTNFR1 plasmid significantly suppressed the increase in the TNF-alpha bioactivity. The sTNFR1 plasmid significantly reduced DNA fragmentation and caspase activity compared to the LacZ plasmid. Finally, the sTNFR1 expression-plasmid treatment significantly reduced the area of myocardial infarction at 2 days after ischemia/reperfusion compared to LacZ plasmid. In conclusion, the TNF-alpha bioactivity in the heart increased from the early stage of ischemia/reperfusion, and this increase was thought to contribute in part to the increased area of myocardial infarction. Suppression of TNF-alpha bioactivity with the sTNFR1 plasmid reduced the infarct size in AMI following ischemia and reperfusion.

  12. Neuronal nitric oxide contributes to neuroplasticity-associated protein expression through cGMP, protein kinase G, and extracellular signal-regulated kinase.

    Science.gov (United States)

    Gallo, Eduardo F; Iadecola, Costantino

    2011-05-11

    Nitric oxide (NO) synthesized by neuronal NO synthase (nNOS) has long been implicated in brain plasticity. However, it is unclear how this short-lived mediator contributes to the long-term molecular changes underlying neuroplasticity, which typically require activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) signaling pathway and gene expression. To address this issue, we used a neuroplasticity model based on treatment of neuronal cultures with bicuculline and a model of experience-dependent plasticity in the barrel cortex. In neuronal cultures, NOS inhibition attenuated the bicuculline-induced activation of ERK and the expression of c-Fos, Egr-1, Arc, and brain-derived neurotrophic factor (BDNF), proteins essential for neuroplasticity. Furthermore, inhibition of the NO target soluble guanylyl cyclase or of the cGMP effector kinase protein kinase G (PKG) reduced both ERK activation and plasticity-related protein expression. NOS inhibition did not affect phosphorylation of cAMP response element-binding protein (CREB), a well-established ERK nuclear target, but it attenuated the nuclear accumulation of the CREB coactivator TORC1 and suppressed the activation of Elk-1, another transcription factor target of ERK. Consistent with these in vitro observations, induction of c-Fos, Egr-1, and BDNF was attenuated in the D1 cortical barrel of nNOS(-/-) mice subjected to single whisker experience. These results establish nNOS-derived NO as a key factor in the expression of proteins involved in neuroplasticity, an effect mediated through cGMP, PKG, and ERK signaling. These actions of NO do not depend on CREB phosphorylation but may involve TORC1 and Elk-1. Our data unveil a previously unrecognized link between neuronal NO and the molecular machinery responsible for the sustained synaptic changes underlying neuroplasticity.

  13. Role of tumour necrosis factor receptor-1 and nuclear factor-κB in production of TNF-α-induced pro-inflammatory microparticles in endothelial cells.

    Science.gov (United States)

    Lee, S K; Yang, S-H; Kwon, I; Lee, O-H; Heo, J H

    2014-09-02

    Tumour necrosis factor-α (TNF-α) is upregulated in many inflammatory diseases and is also a potent agent for microparticle (MP) generation. Here, we describe an essential role of TNF-α in the production of endothelial cell-derived microparticles (EMPs) in vivo and the function of TNF-α-induced EMPs in endothelial cells. We found that TNF-α rapidly increased blood levels of EMPs in mice. Treatment of human umbilical vein endothelial cells (HUVECs) with TNF-α also induced EMP formation in a time-dependent manner. Silencing of TNF receptor (TNFR)-1 or inhibition of the nuclear factor-κB (NF-κB) in HUVECs impaired the production of TNF-α-induced EMP. Incubation of HUVECs with PKH-67-stained EMPs showed that endothelial cells readily engulfed EMPs, and the engulfed TNF-α-induced EMPs promoted the expression of pro-apoptotic molecules and upregulated intercellular adhesion molecule-1 level on the cell surface, which led to monocyte adhesion. Collectively, our findings indicate that the generation of TNF-α-induced EMPs was mediated by TNFR1 or NF-κB and that EMPs can contribute to apoptosis and inflammation of endothelial cells.

  14. Induction of immune response in macaque monkeys infected with simian-human immunodeficiency virus having the TNF-α gene at an early stage of infection

    International Nuclear Information System (INIS)

    Shimizu, Yuya; Miyazaki, Yasuyuki; Ibuki, Kentaro; Suzuki, Hajime; Kaneyasu, Kentaro; Goto, Yoshitaka; Hayami, Masanori; Miura, Tomoyuki; Haga, Takeshi

    2005-01-01

    TNF-α has been implicated in the pathogenesis of, and the immune response against, HIV-1 infection. To clarify the roles of TNF-α against HIV-1-related virus infection in an SHIV-macaque model, we genetically engineered an SHIV to express the TNF-α gene (SHIV-TNF) and characterized the virus's properties in vivo. After the acute viremic stage, the plasma viral loads declined earlier in the SHIV-TNF-inoculated monkeys than in the parental SHIV (SHIV-NI)-inoculated monkeys. SHIV-TNF induced cell death in the lymph nodes without depletion of circulating CD4 + T cells. SHIV-TNF provided some immunity in monkeys by increasing the production of the chemokine RANTES and by inducing an antigen-specific proliferation of lymphocytes. The monkeys immunized with SHIV-TNF were partly protected against a pathogenic SHIV (SHIV-C2/1) challenge. These findings suggest that TNFcontributes to the induction of an effective immune response against HIV-1 rather than to the progression of disease at the early stage of infection

  15. Thymoquinone inhibits TNF-α-induced inflammation and cell adhesion in rheumatoid arthritis synovial fibroblasts by ASK1 regulation

    International Nuclear Information System (INIS)

    Umar, Sadiq; Hedaya, Omar; Singh, Anil K.; Ahmed, Salahuddin

    2015-01-01

    Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine produced by monocytes/macrophage that plays a pathological role in rheumatoid arthritis (RA). In this study, we investigate the effect of thymoquinone (TQ), a phytochemical found in Nigella sativa, in regulating TNF-α-induced RA synovial fibroblast (RA-FLS) activation. Treatment with TQ (1–5 μM) had no marked effect on the viability of human RA-FLS. Pre-treatment of TQ inhibited TNF-α-induced interleukin-6 (IL-6) and IL-8 production and ICAM-1, VCAM-1, and cadherin-11 (Cad-11) expression in RA-FLS (p < 0.01). Evaluation of the signaling events showed that TQ inhibited TNF-α-induced phospho-p38 and phospho-JNK expression, but had no inhibitory effect on NF-κB pathway, in RA-FLS (p < 0.05; n = 4). Interestingly, we observed that selective down-regulation of TNF-α-induced phospho-p38 and phospho-JNK activation by TQ is elicited through inhibition of apoptosis-regulated signaling kinase 1 (ASK1). Furthermore, TNF-α selectively induced phosphorylation of ASK1 at Thr845 residue in RA-FLS, which was inhibited by TQ pretreatment in a dose dependent manner (p < 0.01). Pre-treatment of RA-FLS with ASK1 inhibitor (TC ASK10), blocked TNF-α induced expression of ICAM-1, VCAM-1, and Cad-11. Our results suggest that TNF-α-induced ASK1-p38/JNK pathway is an important mediator of cytokine synthesis and enhanced expression of adhesion molecule in RA-FLS and TQ, by selectively inhibiting this pathway, may have a potential therapeutic value in regulating tissue destruction observed in RA. - Highlights: • Evolving evidence suggests that ASK1 plays a central role in rheumatic arthritis (RA). • TNF-α activates ASK1, which regulate downstream signaling through JNK/p38 activation in RA-FLS. • ASK1 may be used as a potential therapeutic target in RA. • Thymoquinone was able to selectively inhibit TNF-α-induced phosphorylation of ASK1 in RA-FLS. • Thymoquinone might serve as a potential small

  16. Thymoquinone inhibits TNF-α-induced inflammation and cell adhesion in rheumatoid arthritis synovial fibroblasts by ASK1 regulation

    Energy Technology Data Exchange (ETDEWEB)

    Umar, Sadiq; Hedaya, Omar; Singh, Anil K.; Ahmed, Salahuddin, E-mail: salah.ahmed@wsu.edu

    2015-09-15

    Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine produced by monocytes/macrophage that plays a pathological role in rheumatoid arthritis (RA). In this study, we investigate the effect of thymoquinone (TQ), a phytochemical found in Nigella sativa, in regulating TNF-α-induced RA synovial fibroblast (RA-FLS) activation. Treatment with TQ (1–5 μM) had no marked effect on the viability of human RA-FLS. Pre-treatment of TQ inhibited TNF-α-induced interleukin-6 (IL-6) and IL-8 production and ICAM-1, VCAM-1, and cadherin-11 (Cad-11) expression in RA-FLS (p < 0.01). Evaluation of the signaling events showed that TQ inhibited TNF-α-induced phospho-p38 and phospho-JNK expression, but had no inhibitory effect on NF-κB pathway, in RA-FLS (p < 0.05; n = 4). Interestingly, we observed that selective down-regulation of TNF-α-induced phospho-p38 and phospho-JNK activation by TQ is elicited through inhibition of apoptosis-regulated signaling kinase 1 (ASK1). Furthermore, TNF-α selectively induced phosphorylation of ASK1 at Thr845 residue in RA-FLS, which was inhibited by TQ pretreatment in a dose dependent manner (p < 0.01). Pre-treatment of RA-FLS with ASK1 inhibitor (TC ASK10), blocked TNF-α induced expression of ICAM-1, VCAM-1, and Cad-11. Our results suggest that TNF-α-induced ASK1-p38/JNK pathway is an important mediator of cytokine synthesis and enhanced expression of adhesion molecule in RA-FLS and TQ, by selectively inhibiting this pathway, may have a potential therapeutic value in regulating tissue destruction observed in RA. - Highlights: • Evolving evidence suggests that ASK1 plays a central role in rheumatic arthritis (RA). • TNF-α activates ASK1, which regulate downstream signaling through JNK/p38 activation in RA-FLS. • ASK1 may be used as a potential therapeutic target in RA. • Thymoquinone was able to selectively inhibit TNF-α-induced phosphorylation of ASK1 in RA-FLS. • Thymoquinone might serve as a potential small

  17. The effect of a metalloproteinase inhibitor (GI5402) on tumor necrosis factor-alpha (TNF-alpha) and TNF-alpha receptors during human endotoxemia

    NARCIS (Netherlands)

    Dekkers, P. E.; Lauw, F. N.; ten Hove, T.; te Velde, A. A.; Lumley, P.; Becherer, D.; van Deventer, S. J.; van der Poll, T.

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is released from the cell surface by cleavage of pro-TNF-alpha by metalloproteinases (MPs). In cell cultures, inhibition of MPs has been found not only to reduce the release of TNF-alpha, but also to enhance the surface expression of TNF-alpha and TNF-alpha

  18. Tumor necrosis factor-alpha and apoptosis signal-regulating kinase 1 control reactive oxygen species release, mitochondrial autophagy, and c-Jun N-terminal kinase/p38 phosphorylation during necrotizing enterocolitis.

    Science.gov (United States)

    Baregamian, Naira; Song, Jun; Bailey, C Eric; Papaconstantinou, John; Evers, B Mark; Chung, Dai H

    2009-01-01

    Oxidative stress and inflammation may contribute to the disruption of the protective gut barrier through various mechanisms; mitochondrial dysfunction resulting from inflammatory and oxidative injury may potentially be a significant source of apoptosis during necrotizing enterocolitis (NEC). Tumor necrosis factor (TNF)-alpha is thought to generate reactive oxygen species (ROS) and activate the apoptosis signal-regulating kinase 1 (ASK1)-c-Jun N-terminal kinase (JNK)/p38 pathway. Hence, the focus of our study was to examine the effects of TNF-alpha/ROS on mitochondrial function, ASK1-JNK/p38 cascade activation in intestinal epithelial cells during NEC. We found (a) abundant tissue TNF-alpha and ASK1 expression throughout all layers of the intestine in neonates with NEC, suggesting that TNF-alpha/ASK1 may be a potential source (indicators) of intestinal injury in neonates with NEC; (b) TNF-alpha-induced rapid and transient activation of JNK/p38 apoptotic signaling in all cell lines suggests that this may be an important molecular characteristic of NEC; (c) TNF-alpha-induced rapid and transient ROS production in RIE-1 cells indicates that mitochondria are the predominant source of ROS, demonstrated by significantly attenuated response in mitochondrial DNA-depleted (RIE-1-rho) intestinal epithelial cells; (d) further studies with mitochondria-targeted antioxidant PBN supported our hypothesis that effective mitochondrial ROS trapping is protective against TNF-alpha/ROS-induced intestinal epithelial cell injury; (e) TNF-alpha induces significant mitochondrial dysfunction in intestinal epithelial cells, resulting in increased production of mtROS, drop in mitochondrial membrane potential (MMP) and decreased oxygen consumption; (f) although the significance of mitochondrial autophagy in NEC has not been unequivocally shown, our studies provide a strong preliminary indication that TNF-alpha/ROS-induced mitochondrial autophagy may play a role in NEC, and this process is a

  19. Therapeutic TNF Inhibitors can Differentially Stabilize Trimeric TNF by Inhibiting Monomer Exchange

    NARCIS (Netherlands)

    van Schie, Karin A.; Ooijevaar-de Heer, Pleuni; Dijk, Lisanne; Kruithof, Simone; Wolbink, Gertjan; Rispens, Theo

    2016-01-01

    Tumor necrosis factor (TNF) is a homotrimeric cytokine that is a key mediator of inflammation. It is unstable at physiological concentrations and slowly converts into an inactive form. Here, we investigated the mechanism of this process by using a Forster resonance energy transfer (FRET) assay that

  20. Leptin and TNF-alpha levels in patients with chronic obstructive pulmonary disease and their relationship to nutritional parameters.

    Science.gov (United States)

    Calikoglu, Mukadder; Sahin, Gulsah; Unlu, Ali; Ozturk, Candan; Tamer, Lülüfer; Ercan, Bahadir; Kanik, Arzu; Atik, Uğur

    2004-01-01

    Leptin is a protein mainly secreted by adipocytes, and the major function of leptin was its role in body weight regulation. In humans, there was a strong correlation between leptin and nutritional parameters, such as body mass index (BMI) and fat mass (FM). Administration of recombinant leptin to OB/OB mice, which have a genetic defect in leptin production, reduces food intake, increases energy expenditure, and decreases body weight. It is suggested that increased levels of circulating leptin levels may contribute to anorexia and weight loss in pathologic conditions including chronic obstructive pulmonary disease (COPD). Recent studies have provided evidence for a link between leptin and proinflammatory cytokines such as TNF-alpha. This study aimed to detect serum leptin and TNF-alpha levels in COPD patients without weight loss during stable disease and acute exacerbation, and to investigate relationships between leptin, TNF-alpha and nutritional parameters at different stages of the disease. 26 stable COPD patients, 16 COPD patients with acute exacerbation and 15 control subjects participated in this study. To eliminate the effects of sex differences, all patients and controls were male. BMI, percent ideal body weight, percent FM, sum of skinfold thickness and serum leptin and TNF-alpha levels were measured in all participants. Leptin and TNF-alpha levels were measured by ELISA. Serum leptin and TNF-alpha levels were significantly higher in the patients experiencing exacerbation than in the stable patients and controls. Although leptin levels were lower and TNF-alpha levels were higher in the stable patient group than in the controls, these differences were not statistically different. Leptin levels were significantly correlated with the nutritional parameters in both control and stable groups. However, in patients with acute exacerbation, a correlation between leptin and nutritional parameters was not found. There was no significant relationship between TNF

  1. A20 inhibits the motility of HCC cells induced by TNF

    Science.gov (United States)

    Xiao, Ying; Li, Na; Guo, Chun; Zhang, Lining; Shi, Yongyu

    2016-01-01

    Metastasis of hepatocellular carcinoma (HCC) can be facilitated by TNF-α, a prototypical inflammatory cytokine in the HCC microenvironment. A20 is a negative regulator of NF-κB signaling pathway. In the present study we ask whether A20 plays a role in HCC metastasis. We found that A20 expression was downregulated in the invasive cells of microvascular invasions (MVI) compared with the noninvasive cells in 89 tissue samples from patients with HCC by immunochemistry methods. Overexpression of A20 in HCC cell lines inhibited their motility induced by TNF-α. Furthermore, the overexpression of A20 inhibited epithelial-mesenchymal transition (EMT), FAK activation and RAC1 activity. By contrast, knockdown of A20 in one HCC cell line results in the converse. In addition, the overexpression of A20 restrained the formation of MVI in HCC xenograft in nude mice treated with TNF-α. All the results suggested that A20 functioned as a negative regulator in motility of HCC cells induced by TNF-α. PMID:26909601

  2. TNF-R1 and FADD mediate UVB-Induced activation of K+ channels in corneal epithelial cells

    Science.gov (United States)

    Boersma, Peter M.; Haarsma, Loren D.; Schotanus, Mark P.; Ubels, John L.

    2017-01-01

    The goal of this study was to elucidate the role of Fas, TNF-R1, FADD and cytochrome c in UVB-induced K+ channel activation, an early step in UVB-induced apoptosis, in human corneal limbal epithelial (HCLE) cells. HCLE cells were treated with Fas, TNF-R1 or FADD siRNA and exposed to 80 or 150 mJ/cm2 UVB. K+ channel activation and loss of intracellular K+ were measured using whole-cell patch-clamp recording and ion chromatography, respectively. Cytochrome c was measured with an ELISA kit. Cells in which Fas was knocked down exhibited identical UVB-induced K+ channel activation and loss of intracellular K+ to control cells. Cells in which TNF-R1 or FADD were knocked down demonstrated reduced K+ channel activation and decreased loss of intracellular K+ following UVB, relative to control cells. Application of TNF-α, the natural ligand of TNF-R1, to HCLE cells induced K+ channel activation and loss of intracellular K+. Cytochrome c was translocated to the cytosol by 2 h after exposure to 150 mJ/cm2 UVB. However, there was no release by 10 min post-UVB. The data suggest that UVB activates TNF-R1, which in turn may activate K+ channels via FADD. This conclusion is supported by the observation that TNF-α also causes loss of intracellular K+. This signaling pathway appears to be integral to UVB-induced K+ efflux, since knockdown of TNF-R1 or FADD inhibits the UVB-induced K+ efflux. The lack of rapid cytochrome c translocation indicates cytochrome c does not play a role in UVB-induced K+ channel activation. PMID:27818316

  3. Cervical Cancer HeLa Cell Autocrine Apoptosis Induced by Co-immobilized TNF-α plus IFN-γ Biomaterials.

    Science.gov (United States)

    Li, Jian; Zhang, Yuxiao; Chen, Liyi; Lu, Xinhua; Li, Zhibin; Xue, Yongyong; Guan, Yan-Qing

    2018-02-13

    Based on our earlier work with co-immobilized TNF-α plus IFN-γ induction of HeLa cell death, we used FRET and XRD techniques to examine the differences in the structure of co-immobilized TNF-α plus IFN-γ and free TNF-α plus IFN-γ. The expressions of both TNF-α and IFN-α increased significantly, as determined by gene microarray analysis, however, in the presence of TNF-α plus IFN-α inhibitors, TNF-α and IFN-α did not increase in HeLa cells induced by co-immobilized TNF-γ plus IFN-α. This suggests that the TNF-α and IFN-α are the results of autocrine signaling in HeLa cells, and that cell death is caused by these substances. The mortality was then measured by flow cytometry and the results demonstrate that co-immobilized TNF-α plus IFN-γ induced death is a type of autocrine-induced apoptosis in HeLa cells. In addition, we performed Elisa, RT-PCR, flow cytometry, and western blot analyses, as well as a series of analytical tests at the animal level. We demonstrated that at both the cellular and animal levels, HeLa cells induced by co-immobilized IFN-γ plus TNF-α secrete much more IFN-α and TNF-α, than these two cytokines could exert on HeLa cells alone, and that this leads to cancer cell death.

  4. Both functional LTbeta receptor and TNF receptor 2 are required for the development of experimental cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Dieudonnée Togbe

    Full Text Available BACKGROUND: TNF-related lymphotoxin alpha (LTalpha is essential for the development of Plasmodium berghei ANKA (PbA-induced experimental cerebral malaria (ECM. The pathway involved has been attributed to TNFR2. Here we show a second arm of LTalpha-signaling essential for ECM development through LTbeta-R, receptor of LTalpha1beta2 heterotrimer. METHODOLOGY/PRINCIPAL FINDINGS: LTbetaR deficient mice did not develop the neurological signs seen in PbA induced ECM but died at three weeks with high parasitaemia and severe anemia like LTalphabeta deficient mice. Resistance of LTalphabeta or LTbetaR deficient mice correlated with unaltered cerebral microcirculation and absence of ischemia, as documented by magnetic resonance imaging and angiography, associated with lack of microvascular obstruction, while wild-type mice developed distinct microvascular pathology. Recruitment and activation of perforin(+ CD8(+ T cells, and their ICAM-1 expression were clearly attenuated in the brain of resistant mice. An essential contribution of LIGHT, another LTbetaR ligand, could be excluded, as LIGHT deficient mice rapidly succumbed to ECM. CONCLUSIONS/SIGNIFICANCE: LTbetaR expressed on radioresistant resident stromal, probably endothelial cells, rather than hematopoietic cells, are essential for the development of ECM, as assessed by hematopoietic reconstitution experiment. Therefore, the data suggest that both functional LTbetaR and TNFR2 signaling are required and non-redundant for the development of microvascular pathology resulting in fatal ECM.

  5. Selective inhibition of TNFR1 reduces osteoclast numbers and is differentiated from anti-TNF in a LPS-driven model of inflammatory bone loss.

    Science.gov (United States)

    Espirito Santo, A I; Ersek, A; Freidin, A; Feldmann, M; Stoop, A A; Horwood, N J

    2015-09-04

    The treatment of autoimmune disorders has been revolutionised by the introduction of biologics such as anti-tumour necrosis factor (anti-TNF). Although in rheumatoid arthritis patients a bone sparing effect of anti-TNF has been shown, the mechanism is not fully understood. Anti-TNF molecules block tumour necrosis factor (TNF) and prevent signalling via both TNF receptor 1 (TNFR1; p55) and TNF receptor 2 (TNFR2; p75). However, signalling via TNFR2 is reported to have protective effects in a number of cell and organ systems. Hence we set out to investigate if pharmacological inhibition of TNFR1 had differential effects compared to pan-TNF inhibition in both an in vitro cell-based model of human osteoclast activity and an in vivo mouse model of lipopolysaccharide (LPS)-induced osteolysis. For the in vitro experiments the anti-human TNFR1 domain antibody (dAb) DMS5541 was used, whereas for the in vivo mouse experiments the anti-mouse TNFR1 dAb DMS5540 was used. We show that selective blocking of TNFR1 signalling reduced osteoclast formation in the presence of TNF. Subcutaneous LPS injection over the calvaria leads to the development of osteolytic lesions within days due to inflammation driven osteoclast formation. In this model, murine TNFR2 genetically fused with mouse IgG1 Fc domain (mTNFR2.Fc), an anti-TNF, did not protect from bone loss in contrast to anti-TNFR1, which significantly reduced lesion development, inflammatory infiltrate, and osteoclast number and size. These results support further exploring the use of TNFR1-selective inhibition in inflammatory bone loss disorders such as osteomyelitis and peri-prosthetic aseptic loosening. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Functional interaction between hMYH and hTRADD in the TNF-α-mediated survival and death pathways of HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Vy Tran, An Hue; Hahm, Soo-Hyun; Han, Se Hee [Department of Advanced Technology Fusion, Konkuk University, Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Chung, Ji Hyung [Department of Applied Bioscience, College of Life Science, CHA University, Gyeonggi-do 463-836 (Korea, Republic of); Park, Geon Tae [Cornell University, Ithaca, NY 14850 (United States); Han, Ye Sun, E-mail: yshan@konkuk.ac.kr [College of Global Integrated Studies, Division of Interdisciplinary Studies, Konkuk University, Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)

    2015-07-15

    Highlights: • We determine the interaction between hMYH and hTRADD. • We examine changes in the level of hMYH–hTRADD interaction under TNF-α treatment. • hTRADD–hMYH association is involved in the nuclear translocation of NFκB. • hTRADD–hMYH complex influences the TNFR1–TRADD association. - Abstract: The tumor necrosis factor (TNF) signaling pathway is a classical immune system pathway that plays a key role in regulating cell survival and apoptosis. The TNF receptor-associated death domain (TRADD) protein is recruited to the death domain of TNF receptor 1 (TNFR1), where it interacts with TNF receptor-associated factor 2 (TRAF2) and receptor-interacting protein (RIP) for the induction of apoptosis, necrosis, nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), and mitogen-activated protein (MAP) kinase activation. In this study, we found that the human MutY homolog (hMYH) interacted with human TRADD (hTRADD) via the C-terminal domain of hMYH. Moreover, under conditions promoting TNF-α-induced cell death or survival in HeLa cells, this interaction was weakened or enhanced, respectively. The interaction between hMYH and hTRADD was important for signaling pathways mediated by TNF-α. Our results also suggested that the hTRADD–hMYH association was involved in the nuclear translocation of NFκB and formation of the TNFR1–TRADD complex. Thus, this study identified a novel mechanism through which the hMYH–hTRADD interaction may affect the TNFsignaling pathway. Implications: In HeLa cells, the hTRADD–hMYH interaction functioned in both cell survival and apoptosis pathways following TNF-α stimulation.

  7. PENCEGAHAN KOMPLIKASI TUBERCULOSIS AKIBAT PEMBERIAN TNF-α ANTAGONIS

    Directory of Open Access Journals (Sweden)

    Huriatul Masdar

    2009-05-01

    Full Text Available AbstrakTNF-α antagonis telah digunakan secara luas dan menunjukan respon yang baik pada terapi penyakit-penyakit autoimun seperti Rheumatoid Artritis, psoriasis dan Inflammatory Bowel Diseases. Namun, beberapa penelitian melaporkan adanya komplikasi tuberculosis yang terjadi akibat penggunaan obat ini dalam jangka lama. Untuk meminimalisir komplikasi tersebut, skrining adanya TB dengan TST, IGRA dan pemeriksaan radiologi wajib dilakukan sebelum pemberian terapi dengan TNF-α antagonis. Pemeriksaan berkala adanya TB juga harus dilakukan selama pemberian terapi. Selain itu, pemilihan obat yang tepat dengan komplikasi minimal juga harus dilakukan untuk menekan aktivasi TB tersebut.Kata Kunci: TNF-α, TNF-α antagonis, penyakit autoimun, tuberculosis.AbstractTNF-α antagonist has been widely used and showed well responses in autoimmune diseases therapy such as Rheumatoid Arthritis, psoriasis and Inflammatory Bowel Diseases. However, many studies showed that the long time used of those biological agents activate tuberculosis infection. To minimize the complication, first, TB screening by TST, IGRA and radiology examination must be performed to exclude latent TB before starting the therapy using TNF-α antagonist. Second, regular TB check must also be done during TNF-α antagonist treatment. At last, choosing right agents for better treatment with less complication must be considered.Keywords: TNF-α, TNF-α antagonist, autoimmune diseases, tuberculosis.

  8. Weight Gain and Hair Loss during Anti-TNF Therapy

    Directory of Open Access Journals (Sweden)

    Abdo Lutf

    2012-01-01

    Full Text Available Objectives. To investigate the incidence of weight gain and hair loss as adverse effects of anti-TNF therapy in rheumatic diseases. Methods. Patients using anti-TNF therapy, who are followed in rheumatology clinic, were interviewed using a questionnaire to investigate the side effects of anti-TNF therapy. Patients who complained of hair loss and weight gain were asked additional questions concerning the relationship of these adverse effects to anti-TNF use, whether therapy was stopped because of these adverse effects and if the adverse effects reversed after stopping therapy. The files were reviewed to follow the weight change before, during, and after discontinuation of anti-TNF. Results. One hundred fifty consecutive patients (82 RA, 34 ankylosing spondylitis, 32 psoriatic arthritis, and 4 for other indications were interviewed .Weight gain was observed in 20 patients (13.3% with average gain of 5.5 Kg. Anti-TNF was stopped in five patients because of this adverse effect. Hair loss during anti-TNf therapy was reported in five females (3.3% and anti-TNF therapy was stopped in all of them. Conclusion. Weight gain and hair loss appear to be associated with anti-TNF therapy and may be one reason for discontinuing the therapy.

  9. Ca²⁺ signal contributing to the synthesis and emission of monoterpenes regulated by light intensity in Lilium 'siberia'.

    Science.gov (United States)

    Hu, Zenghui; Li, Tianjiao; Zheng, Jian; Yang, Kai; He, Xiangfeng; Leng, Pingsheng

    2015-06-01

    The floral scent is an important part of plant volatile compounds, and is influenced by environmental factors. The emission of monoterpenes of Lilium 'siberia' is regulated by light intensity, but the mechanism is large unknown. In this study, the expression of Li-mTPS, a monoterpene synthase gene in the tepals of Lilium 'siberia', and net Ca(2+) flux were investigated after exposure to different levels of light intensity (0, 100, 300, 600, 1000, and 1500 μmol m(-2) s(-1)). Moreover the effect of LaCl3 and ethylene glycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) on the Li-mTPS expression, monoterpene emission, and net Ca(2+) flux were examined at 600 μmol m(-2) s(-1). The results showed that along with the enhancement of light intensity, the expression level of Li-mTPS increased gradually, and the net Ca(2+) influx was also enhanced showing a similar pattern. It was found that LaCl3 and EGTA effectively inhibited the increase in expression of Li-mTPS and the net Ca(2+) influx induced by light treatment. Moreover, the release amounts of monoterpenes decreased significantly after treatment with LaCl3 and EGTA. So it can be concluded that Ca(2+) signal contributed to the biosynthesis and emission of monoterpenes regulated by light intensity in Lilium 'siberia' tepals. The increased light intensity firstly triggered the Ca(2+) influx to cytoplasm, and then the gene expression of monoterpene synthases downstream was activated to regulate the biosynthesis and emission of monoterpenes. But in the signaling pathway other mechanisms were thought to be involved in the emission of monoterpenes regulated by light intensity, which need to be investigated in future research. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Synapse-specific changes in serotonin signalling contribute to age-related changes in the feeding behaviour of the pond snail, Lymnaea.

    Science.gov (United States)

    Yeoman, Mark S; Patel, Bhavik A; Arundell, Martin; Parker, Kim; O'Hare, Danny

    2008-08-01

    This study utilised the pond snail, Lymnaea to examine the contribution that alterations in serotonergic signalling make to age-related changes in feeding. Age-related decreases in 5-HIAA levels in feeding ganglia were positively correlated with a decrease in the number of sucrose-evoked bites and negatively correlated with an increase in inter-bite interval, implicating alterations in serotonergic signalling in the aged phenotype. Analysis of the serotonergic cerebral giant cell (CGC) input to the protraction motor neurone (B1) demonstrated that fluoxetine (10-100 nM) increased the amplitude/duration of the evoked EPSP in both young and middle aged but not in old neurones, suggesting an age-related attenuation of the serotonin transporter. 5-HT evoked a concentration-dependent increase in the amplitude/duration of B1 EPSP, which was greater in old neurones compared to both young and middle aged. Conversely, the 5-HT-evoked depolarisation and conditional bursting of the swallow motor neurone (B4) were attenuated in old neurones, functions critical for a full feeding rhythm. The CGCs' ability to excite B1 was blocked by cinanserin but not by methysergide. Conversely, the CGC to B4 connection was completely blocked by methysergide and only partially by cinanserin suggesting that age-related changes may be receptor-specific. In summary, synapse-specific attenuation of the CGC-B4 connection and enhancement of the CGC-B1 connection would slow the swallow phase and maintain protraction, consistent with behavioural observations.

  11. β adrenergic receptor/cAMP/PKA signaling contributes to the intracellular Ca2+release by tentacle extract from the jellyfish Cyanea capillata.

    Science.gov (United States)

    Wang, Qianqian; Zhang, Hui; Wang, Bo; Wang, Chao; Xiao, Liang; Zhang, Liming

    2017-07-25

    Intracellular Ca 2+ overload induced by extracellular Ca 2+ entry has previously been confirmed to be an important mechanism for the cardiotoxicity as well as the acute heart dysfunction induced by jellyfish venom, while the underlying mechanism remains to be elucidated. Under extracellular Ca 2+ -free or Ca 2+ -containing conditions, the Ca 2+ fluorescence in isolated adult mouse cardiomyocytes pre-incubated with tentacle extract (TE) from the jellyfish Cyanea capillata and β blockers was scanned by laser scanning confocal microscope. Then, the cyclic adenosine monophosphate (cAMP) concentration and protein kinase A (PKA) activity in primary neonatal rat ventricular cardiomyocytes were determined by ELISA assay. Furthermore, the effect of propranolol against the cardiotoxicity of TE was evaluated in Langendorff-perfused rat hearts and intact rats. The increase of intracellular Ca 2+ fluorescence signal by TE was significantly attenuated and delayed when the extracellular Ca 2+ was removed. The β adrenergic blockers, including propranolol, atenolol and esmolol, partially inhibited the increase of intracellular Ca 2+ in the presence of 1.8 mM extracellular Ca 2+ and completely abolished the Ca 2+ increase under an extracellular Ca 2+ -free condition. Both cAMP concentration and PKA activity were stimulated by TE, and were inhibited by the β adrenergic blockers. Cardiomyocyte toxicity of TE was antagonized by β adrenergic blockers and the PKA inhibitor H89. Finally, the acute heart dysfuction by TE was antagonized by propranolol in Langendorff-perfused rat hearts and intact rats. Our findings indicate that β adrenergic receptor/cAMP/PKA signaling contributes to the intracellular Ca 2+ overload through intracellular Ca 2+ release by TE from the jellyfish C. capillata.

  12. Minimal contribution of ERK1/2-MAPK signalling towards the maintenance of oncogenic GNAQQ209P-driven uveal melanomas in zebrafish

    Science.gov (United States)

    Mouti, Mai Abdel; Dee, Christopher; Coupland, Sarah E.; Hurlstone, Adam F.L.

    2016-01-01

    Mutations affecting Gαq proteins are pervasive in uveal melanoma (UM), suggesting they ‘drive’ UM pathogenesis. The ERK1/2-MAPK pathway is critical for cutaneous melanoma development and consequently an important therapeutic target. Defining the contribution of ERK1/2-MAPK signalling to UM development has been hampered by the lack of an informative animal model that spontaneously develops UM. Towards this end, we engineered transgenic zebrafish to express oncogenic GNAQQ209P in the melanocyte lineage. This resulted in hyperplasia of uveal melanocytes, but with no evidence of malignant progression, nor perturbation of skin melanocytes. Combining expression of oncogenic GNAQQ209P with p53 inactivation resulted in earlier onset and even more extensive hyperplasia of uveal melanocytes that progressed to UM. Immunohistochemistry revealed only weak immunoreactivity to phosphorylated (p)ERK1/2 in established uveal tumours—in contrast to strong immunoreactivity in oncogenic RAS-driven skin lesions—but ubiquitous positive staining for nuclear Yes-associated protein (YAP). Moreover, no changes were observed in pERK1/2 levels upon transient knockdown of GNAQ or phospholipase C-beta (PLC-β) inhibition in the majority of human UM cell lines we tested harbouring GNAQ mutations. In summary, our findings demonstrate a weak correlation between oncogenic GNAQQ209P mutation and sustained ERK1/2-MAPK activation, implying that ERK1/2 signalling is unlikely to be instrumental in the maintenance of GNAQQ209P-driven UMs. PMID:27166257

  13. TNF-α-induced LRG1 promotes angiogenesis and mesenchymal stem cell migration in the subchondral bone during osteoarthritis.

    Science.gov (United States)

    Wang, Yiyun; Xu, Jiajia; Zhang, Xudong; Wang, Chuandong; Huang, Yan; Dai, Kerong; Zhang, Xiaoling

    2017-03-30

    The incomplete understanding of aberrant neovascularization, which contributes to osteoarthritis suggests that additional modulators have yet to be identified. Our objective was to identify the role of Leucine-rich-alpha-2-glycoprotein1 (LRG1), a new regulator of pathogenic angiogenesis, in osteoarthritis progression and to develop effective treatment strategies. In this study, immunohistochemistry showed that LRG1 was increased in the subchondral bone and articular cartilage in anterior cruciate ligament transection (ACLT) mice. Further studies were focused on the role of LRG1 in osteoarthritis. Results showed that LRG1 promoted angiogenesis and mesenchymal stem cells (MSC) migration, which contribute to aberrant bone formation in the subchondral bone. Moreover, tumor necrosis factor-α (TNF-α), not interleukin-1β (IL-1β), IL-6 or IL-17, induced the LRG1 expression in human umbilical vein endothelial cells and this effect was inhibited by p38 mitogen-activated protein kinase or NF-κB inhibitor. Notably, inhibition of TNF-α and LRG1 activity by Lenalidomide, an inhibitor of TNF-α production, in ACLT mice attenuated degeneration of osteoarthritis articular cartilage. This study shows that TNF-α is the predominant proinflammatory cytokine that induces the secretion of LRG1. LRG1 contributes to angiogenesis-coupled de novo bone formation by increasing angiogenesis and recruiting MSCs in the subchondral bone of osteoarthritis joints. Inhibition of TNF-α and LRG1 by Lenalidomide could be a potential therapeutic approach.

  14. Confirmation of an IRAK3 polymorphism as a genetic marker predicting response to anti-TNF treatment in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Sode, Jacob; Vogel, U; Bank, Steffen

    2018-01-01

    Several genetic variants in Toll-like receptor (TLR) and nuclear factor (NF)-κB signalling pathways have been reported associated with responsiveness to tumour necrosis factor inhibitor (anti-TNF) treatment in rheumatoid arthritis (RA). The present study was undertaken to replicate these findings...... online publication, 4 October 2016; doi:10.1038/tpj.2016.66....

  15. Estrogen Deficiency Exacerbates Type 1 Diabetes-Induced Bone TNF-α Expression and Osteoporosis in Female Mice.

    Science.gov (United States)

    Raehtz, Sandi; Bierhalter, Hayley; Schoenherr, Daniel; Parameswaran, Narayanan; McCabe, Laura R

    2017-07-01

    Estrogen deficiency after menopause is associated with rapid bone loss, osteoporosis, and increased fracture risk. Type 1 diabetes (T1D), characterized by hypoinsulinemia and hyperglycemia, is also associated with bone loss and increased fracture risk. With better treatment options, T1D patients are living longer; therefore, the number of patients having both T1D and estrogen deficiency is increasing. Little is known about the mechanistic impact of T1D in conjunction with estrogen deficiency on bone physiology and density. To investigate this, 11-week-old mice were ovariectomized (OVX), and T1D was induced by multiple low-dose streptozotocin injection. Microcomputed tomographic analysis indicated a marked reduction in trabecular bone volume fraction (BVF) in T1D-OVX mice (~82%) that was far greater than the reductions (~50%) in BVF in either the OVX and T1D groups. Osteoblast markers, number, and activity were significantly decreased in T1D-OVX mice, to a greater extent than either T1D or OVX mice. Correspondingly, marrow adiposity was significantly increased in T1D-OVX mouse bone. Bone expression analyses revealed that tumor necrosis factor (TNF)-α levels were highest in T1D-OVX mice and correlated with bone loss, and osteoblast and osteocyte death. In vitro studies indicate that estrogen deficiency and high glucose enhance TNF-α expression in response to inflammatory signals. Taken together, T1D combined with estrogen deficiency has a major effect on bone inflammation, which contributes to suppressed bone formation and osteoporosis. Understanding the mechanisms/effects of estrogen deficiency in the presence of T1D on bone health is essential for fracture prevention in this patient population. Copyright © 2017 Endocrine Society.

  16. Tumour necrosis factor-alpha (TNF), lymphotoxin and TNF receptor levels in serum from patients with Wegener's granulomatosis

    DEFF Research Database (Denmark)

    Jónasdóttir, O; Petersen, J; Bendtzen, K

    2001-01-01

    Wegener's granulomatosis (WG) is a systemic inflammatory disease with vasculitis as the key feature. Abnormal expression of tumour necrosis factor alpha (TNFalpha) is considered of prime pathogenic importance in several inflammatory diseases. The effects of TNFa are mediated by TNF receptors (TNF......-R), and these receptors are often found in soluble forms (sTNF-R), which can modulate TNFalpha actions. To evaluate the clinical importance of the TNF family of cytokines, the serum levels of TNFalpha, TNFbeta, now termed lymphotoxin (LTalpha), and sTNF-R1 and sTNF-R2 were measured by ELISA in 8 patients with WG during...... active disease and during immunosuppressive treatment, and in 11 healthy controls in parallel. Serum concentrations of TNFalpha were undetectable in all except two controls (18%) and three patients with WG (37%). After 7 days of therapy, six of the WG patients had measurable TNFalpha levels. Examination...

  17. Ascorbic acid pre-treated quartz stimulates TNF-α release in RAW 264.7 murine macrophages through ROS production and membrane lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Benvenuto Federica

    2009-03-01

    Full Text Available Abstract Background Inhalation of crystalline silica induces a pulmonary fibrotic degeneration called silicosis caused by the inability of alveolar macrophages to dissolve the crystalline structure of phagocytosed quartz particles. Ascorbic acid is capable of partially dissolving quartz crystals, leading to an increase of soluble silica concentration and to the generation of new radical sites on the quartz surface. The reaction is specific for the crystalline forms of silica. It has been already demonstrated an increased cytotoxicity and stronger induction of pro-inflammatory cyclooxygenase-2 (COX-2 by ascorbic acid pre-treated quartz (QA compared to untreated quartz (Q in the murine macrophage cell line RAW 264.7. Methods Taking advantage of the enhanced macrophage response to QA as compared to Q particles, we investigated the first steps of cell activation and the contribution of early signals generated directly from the plasma membrane to the production of TNF-α, a cytokine that activates both inflammatory and fibrogenic pathways. Results Here we demonstrate that TNF-α mRNA synthesis and protein secretion are significantly increased in RAW 264.7 macrophages challenged with QA as compared to Q particles, and that the enhanced response is due to an increase of intracellular ROS. Plasma membrane-particle contact, in the absence of phagocytosis, is sufficient to trigger TNF-α production through a mechanism involving membrane lipid peroxidation and this appears to be even more detrimental to macrophage survival than particle phagocytosis itself. Conclusion Taken together these data suggest that an impairment of pulmonary macrophage phagocytosis, i.e. in the case of alcoholic subjects, could potentiate lung disease in silica-exposed individuals.

  18. Ascorbic acid pre-treated quartz stimulates TNF-alpha release in RAW 264.7 murine macrophages through ROS production and membrane lipid peroxidation.

    Science.gov (United States)

    Scarfì, Sonia; Magnone, Mirko; Ferraris, Chiara; Pozzolini, Marina; Benvenuto, Federica; Benatti, Umberto; Giovine, Marco

    2009-03-19

    Inhalation of crystalline silica induces a pulmonary fibrotic degeneration called silicosis caused by the inability of alveolar macrophages to dissolve the crystalline structure of phagocytosed quartz particles. Ascorbic acid is capable of partially dissolving quartz crystals, leading to an increase of soluble silica concentration and to the generation of new radical sites on the quartz surface. The reaction is specific for the crystalline forms of silica. It has been already demonstrated an increased cytotoxicity and stronger induction of pro-inflammatory cyclooxygenase-2 (COX-2) by ascorbic acid pre-treated quartz (QA) compared to untreated quartz (Q) in the murine macrophage cell line RAW 264.7. Taking advantage of the enhanced macrophage response to QA as compared to Q particles, we investigated the first steps of cell activation and the contribution of early signals generated directly from the plasma membrane to the production of TNF-alpha, a cytokine that activates both inflammatory and fibrogenic pathways. Here we demonstrate that TNF-alpha mRNA synthesis and protein secretion are significantly increased in RAW 264.7 macrophages challenged with QA as compared to Q particles, and that the enhanced response is due to an increase of intracellular ROS. Plasma membrane-particle contact, in the absence of phagocytosis, is sufficient to trigger TNF-alpha production through a mechanism involving membrane lipid peroxidation and this appears to be even more detrimental to macrophage survival than particle phagocytosis itself. Taken together these data suggest that an impairment of pulmonary macrophage phagocytosis, i.e. in the case of alcoholic subjects, could potentiate lung disease in silica-exposed individuals.

  19. Ascorbic acid pre-treated quartz stimulates TNF-α release in RAW 264.7 murine macrophages through ROS production and membrane lipid peroxidation

    Science.gov (United States)

    Scarfì, Sonia; Magnone, Mirko; Ferraris, Chiara; Pozzolini, Marina; Benvenuto, Federica; Benatti, Umberto; Giovine, Marco

    2009-01-01

    Background Inhalation of crystalline silica induces a pulmonary fibrotic degeneration called silicosis caused by the inability of alveolar macrophages to dissolve the crystalline structure of phagocytosed quartz particles. Ascorbic acid is capable of partially dissolving quartz crystals, leading to an increase of soluble silica concentration and to the generation of new radical sites on the quartz surface. The reaction is specific for the crystalline forms of silica. It has been already demonstrated an increased cytotoxicity and stronger induction of pro-inflammatory cyclooxygenase-2 (COX-2) by ascorbic acid pre-treated quartz (QA) compared to untreated quartz (Q) in the murine macrophage cell line RAW 264.7. Methods Taking advantage of the enhanced macrophage response to QA as compared to Q particles, we investigated the first steps of cell activation and the contribution of early signals generated directly from the plasma membrane to the production of TNF-α, a cytokine that activates both inflammatory and fibrogenic pathways. Results Here we demonstrate that TNF-α mRNA synthesis and protein secretion are significantly increased in RAW 264.7 macrophages challenged with QA as compared to Q particles, and that the enhanced response is due to an increase of intracellular ROS. Plasma membrane-particle contact, in the absence of phagocytosis, is sufficient to trigger TNF-α production through a mechanism involving membrane lipid peroxidation and this appears to be even more detrimental to macrophage survival than particle phagocytosis itself. Conclusion Taken together these data suggest that an impairment of pulmonary macrophage phagocytosis, i.e. in the case of alcoholic subjects, could potentiate lung disease in silica-exposed individuals. PMID:19298665

  20. Association between TNF promoter -308 G>A and LTA 252 A>G polymorphisms and systemic lupus erythematosus.

    Science.gov (United States)

    Ahmed, Hanan Hosni; Taha, Fatma Mohamed; Darweesh, Hanan El-Sayed; Morsi, Heba Mohamed Abdelhafiz

    2014-01-01

    Tumor necrosis factor (TNF) and lymphotoxin alpha (LTA) are pivotal cytokines in the pathogenesis of systemic lupus erythematosus (SLE). To investigate the possible association of the polymorphism of the TNF promoter gene -308 and that of the LTA gene 252 with susceptibility to SLE and with phenotypic disease features in Egyptian patients. A case control study involving 100 SLE patients and 100 unrelated healthy controls. Polymerase chain reaction and restriction fragment length polymorphism methods were applied to detect genetic polymorphism. We found that TNF-308 genotype AA was significantly increase by 26 % in SLE patients compared to 10 % in the control group (p = 0.003; OR 3.16; CI 1.43-6.98) and the frequency of the A allele of the TNF promoter -308 was significantly higher in the SLE patients (42 %) than in the control subjects (24 %) (p manifestations as malar rash, arthritis, oral ulcers, serositis and systemic lupus erythematosus disease activity index. Genotype (GG+GA) of LTA was significantly associated with arthritis. These results suggest that TNF and LTA genetic polymorphisms contribute to SLE susceptibility in the Egyptian population and are associated with disease characteristics. TNF-308 and LTA+252 polymorphic markers may be used for early diagnosis of SLE and early prediction of clinical manifestations, like arthritis.

  1. Molecular mechanisms of action of anti-TNF-α agents - Comparison among therapeutic TNF-α antagonists.

    Science.gov (United States)

    Mitoma, Hiroki; Horiuchi, Takahiko; Tsukamoto, Hiroshi; Ueda, Naoyasu

    2018-01-01

    Tumor necrosis factor (TNF)-α is a potent pro-inflammatory and pathological cytokines in inflammatory diseases such as rheumatoid arthritis and inflammatory bowel diseases. Anti-TNF-α therapy has been established as an efficacious therapeutic strategy in these diseases. In clinical settings, three monoclonal anti-TNF-α full IgG1 antibodies infliximab, adalimumab, and golimumab, PEGylated Fab' fragment of anti-TNF-α antibody certolizumab pegol, extracellular domain of TNF receptor 2/IgG1-Fc fusion protein etanercept, are almost equally effective for rheumatoid arthritis. Although monoclonal full IgG1 antibodies are able to induce clinical and endoscopic remission in inflammatory bowel diseases, certolizumab pegol without Fc portion has been shown to be less effective for inflammatory bowel diseases compared to full IgG1 antibodies. In addition, there are no evidences that etanercept leads clinical remission in inflammatory bowel diseases. Besides the common effect of anti-TNF-α agents on neutralization of soluble TNF-α, each anti-TNF-α agent has its own distinctive pharmacological properties which cause the difference in clinical efficacies. Here we focus on the distinctions of action of anti-TNF-α agents especially in following points; (1) blocking ability against ligands, transmembrane TNF-α and lymphotoxin, (2) effects toward transmembrane TNF-α-expressing cells, (3) effects toward Fcγ receptor-expressing cells, (4) degradation and distribution in inflamed tissue. Accumulating evidence will give us the idea how to modify anti-TNF-α agents to enhance the clinical efficacy in inflammatory diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. TNF-α Differentially Regulates Synaptic Plasticity in the Hippocampus and Spinal Cord by Microglia-Dependent Mechanisms after Peripheral Nerve Injury.

    Science.gov (United States)

    Liu, Yong; Zhou, Li-Jun; Wang, Jun; Li, Dai; Ren, Wen-Jie; Peng, Jiyun; Wei, Xiao; Xu, Ting; Xin, Wen-Jun; Pang, Rui-Ping; Li, Yong-Yong; Qin, Zhi-Hai; Murugan, Madhuvika; Mattson, Mark P; Wu, Long-Jun; Liu, Xian-Guo

    2017-01-25

    Clinical studies show that chronic pain is accompanied by memory deficits and reduction in hippocampal volume. Experimental studies show that spared nerve injury (SNI) of the sciatic nerve induces long-term potentiation (LTP) at C-fiber synapses in spinal dorsal horn, but impairs LTP in the hippocampus. The opposite changes may contribute to neuropathic pain and memory deficits, respectively. However, the cellular and molecular mechanisms underlying the functional synaptic changes are unclear. Here, we show that the dendrite lengths and spine densities are reduced significantly in hippocampal CA1 pyramidal neurons, but increased in spinal neurokinin-1-positive neurons in mice after SNI, indicating that the excitatory synaptic connectivity is reduced in hippocampus but enhanced in spinal dorsal horn in this neuropathic pain model. Mechanistically, tumor necrosis factor-alpha (TNF-α) is upregulated in bilateral hippocampus and in ipsilateral spinal dorsal horn, whereas brain-derived neurotrophic factor (BDNF) is decreased in the hippocampus but increased in the ipsilateral spinal dorsal horn after SNI. Importantly, the SNI-induced opposite changes in synaptic connectivity and BDNF expression are prevented by genetic deletion of TNF receptor 1 in vivo and are mimicked by TNF-α in cultured slices. Furthermore, SNI activated microglia in both spinal dorsal horn and hippocampus; pharmacological inhibition or genetic ablation of microglia prevented the region-dependent synaptic changes, neuropathic pain, and memory deficits induced by SNI. The data suggest that neuropathic pain involves different structural synaptic alterations in spinal and hippocampal neurons that are mediated by overproduction of TNF-α and microglial activation and may underlie chronic pain and memory deficits. Chronic pain is often accompanied by memory deficits. Previous studies have shown that peripheral nerve injury produces both neuropathic pain and memory deficits and induces long

  3. Cytokine production from stimulated whole blood cultures in rheumatoid arthritis patients treated with various TNF blocking agents.

    Science.gov (United States)

    Popa, Calin; Barrera, Pilar; Joosten, Leo A B; van Riel, Piet L C M; Kullberg, Bart-Jan; van der Meer, Jos W M; Netea, Mihai G

    2009-06-01

    Infectious complications are not rare in rheumatoid arthritis (RA), and the susceptibility to infections is increased during treatment with TNF blocking agents. As a possible mechanism contributing to that, we assessed the modulation of cytokine production induced by TNF neutralization. Whole blood cultures from six healthy volunteers and 13 RA patients starting therapy with either adalimumab (n = 7) or etanercept (n = 6) were stimulated with heat-killed Salmonella typhimurium, Staphylococcus aureus or with S. typhimurium lipopolysaccharide (LPS). The production of interleukin (IL)-1beta, IL-6, IL10, IL-17, TNF, IL-8 and IFN-gamma was measured by specific immunoassays. Stimulation with Salmonella LPS resulted in a significantly lower production of IL-1beta, TNF and a trend towards lower IL-6 and IFN-gamma production in RA patients compared to healthy volunteers. Therapy with either of the agents did not significantly alter cytokine production capacity, with the exception of a lower IFN-gamma and IL-8 production in patients treated with adalimumab and stimulated with heat-killed S. aureus. The results of our study suggest that the detrimental effects of anti-TNF agents on the immune response can vary quite widely, from very serious to limited effects, as reported here for etanercept and adalimumab. Because anti-TNF therapy can affect the cellular integrity of tuberculous granuloma, recruitment of new cells at the granuloma site becomes crucial. In line with this, an impaired chemokine production induced by anti-TNF agents may ultimately result in the reactivation of tuberculosis, as previously reported. Therefore, caution should be constantly exercised in order to prevent the development of severe infections and reactivation of tuberculosis whenever therapy with anti-TNF is initiated.

  4. Relationship of bovine TNF-α gene polymorphisms with the risk of bovine tuberculosis in Holstein cattle

    Science.gov (United States)

    CHENG, Yafen; HUANG, ChenShen; TSAI, Hsiang-Jung

    2016-01-01

    Many studies suggest significant genetic variation in the resistance of cattle and humans to infection with Mycobacterium bovis (M. bovis), the causative agent of zoonotic tuberculosis. TNF-α promotes inflammation and induces apoptosis in response to mycobacterial infection. The aim of the present study was to investigate the influence of single nucleotide polymorphisms of the TNF-α gene on bovine tuberculosis (bTB) susceptibility. We genotyped the TNF-α gene in 74 bTB-infected Holstein cows and 90 healthy control animals. The influence in the exon 3 region of TNF-α polymorphisms on bTB susceptibility was subsequently investigated by association analysis. Our finding demonstrated that the g.27534932A>C polymorphism of the TNF-α is associated with bTB in Holstein cattle. The susceptibility of cattle with the g.27534932A>C genotype compared with the CC genotype was 4.11-fold (95% CI, 1.27–13.36; P=0.02) higher. The g.27534932A>C polymorphism located in exon 3 of the TNF-α gene, and the functional consequence was missense. The deduced amino acid sequence for the protein product revealed an arginine to serine conversion at position 159, which may affect initiation of protein synthesis and disrupt normal TNF-α function that protects animals against mycobacterial infection. A significant association was observed with the A allele as a risk factor for bTB susceptibility (OR, 3.84; 95% CI, 1.21–12.17; P=0.02). In conclusion, this is the first report showing that the g.27534932A>C polymorphism may contribute to TNF-α-mediated bTB susceptibility. PMID:26876219

  5. Transmembrane TNF-α is sufficient for articular inflammation and hypernociception in a mouse model of gout.

    Science.gov (United States)

    Amaral, Flávio A; Bastos, Leandro F S; Oliveira, Thiago H C; Dias, Ana C F; Oliveira, Vívian L S; Tavares, Lívia D; Costa, Vivian V; Galvão, Izabela; Soriani, Frederico M; Szymkowski, David E; Ryffel, Bernhard; Souza, Danielle G; Teixeira, Mauro M

    2016-01-01

    Gout manifests as recurrent episodes of acute joint inflammation and pain due to the deposition of monosodium urate (MSU) crystals within the affected tissue in a process dependent on NLRP3 inflammasome activation. The synthesis, activation, and release of IL-1β are crucial for MSU-induced inflammation. The current study evaluated the mechanism by which TNFcontributed to MSU-induced inflammation. Male C57BL/6J or transgenic mice were used in this study and inflammation was induced by the injection of MSU crystals into the joint. TNF-α was markedly increased in the joint after the injection of MSU. There was inhibition in the infiltration of neutrophils, production of CXCL1 and IL-1β, and decreased hypernociception in mice deficient for TNF-α or its receptors. Pharmacological blockade of TNF-α with Etanercept or pentoxyfylline produced similar results. Mechanistically, TNF-α blockade resulted in lower amounts of IL-1β protein and pro-IL-1β mRNA transcripts in joints. Gene-modified mice that express only transmembrane TNF-α had an inflammatory response similar to that of WT mice and blockade of soluble TNF-α (XPro™1595) did not decrease MSU-induced inflammation. In conclusion, TNF-α drives expression of pro-IL-1β mRNA and IL-1β protein in experimental gout and that its transmembrane form is sufficient to trigger MSU-induced inflammation in mice. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Aqueous Extract of Tomato (Solanum lycopersicum L. and Ferulic Acid Reduce the Expression of TNF-α and IL-1β in LPS-Activated Macrophages

    Directory of Open Access Journals (Sweden)

    Simón Navarrete

    2015-08-01

    Full Text Available Acute inflammation is essential for defending the body against pathogens; however, when inflammation becomes chronic, it is harmful to the body and is part of the pathophysiology of various diseases such as Diabetes Mellitus type 2 (DM2 and Cardiovascular Disease (CVD among others. In chronic inflammation macrophages play an important role, mainly through the secretion of proinflammatory cytokines such as Tumor necrosis factor (TNF-α and Interleukin (IL-1β, explained in part by activation of the Toll-like receptor 4 (TLR4, a signaling pathway which culminates in the activation of Nuclear factor (NF-κB, an important transcription factor in the expression of these proinflammatory genes. On the other hand, the benefits on health of a diet rich in fruit and vegetables are well described. In this work, the effects of aqueous extract of tomato and ferulic acid on the expression of proinflammatory cytokines in LPS activated monocyte-derived THP-1 macrophages were investigated. In addition, using Western blot, we investigated whether the inhibition was due to the interference on activation of NF-κB. We found that both the tomato extract and ferulic acid presented inhibitory activity on the expression of TNF-α and IL-1β cytokine by inhibiting the activation of NF-κB. The current results suggest that tomatoes and ferulic acid may contribute to prevention of chronic inflammatory diseases.

  7. Aqueous Extract of Tomato (Solanum lycopersicum L.) and Ferulic Acid Reduce the Expression of TNF-α and IL-1β in LPS-Activated Macrophages.

    Science.gov (United States)

    Navarrete, Simón; Alarcón, Marcelo; Palomo, Iván

    2015-08-21

    Acute inflammation is essential for defending the body against pathogens; however, when inflammation becomes chronic, it is harmful to the body and is part of the pathophysiology of various diseases such as Diabetes Mellitus type 2 (DM2) and Cardiovascular Disease (CVD) among others. In chronic inflammation macrophages play an important role, mainly through the secretion of proinflammatory cytokines such as Tumor necrosis factor (TNF)-α and Interleukin (IL)-1β, explained in part by activation of the Toll-like receptor 4 (TLR4), a signaling pathway which culminates in the activation of Nuclear factor (NF)-κB, an important transcription factor in the expression of these proinflammatory genes. On the other hand, the benefits on health of a diet rich in fruit and vegetables are well described. In this work, the effects of aqueous extract of tomato and ferulic acid on the expression of proinflammatory cytokines in LPS activated monocyte-derived THP-1 macrophages were investigated. In addition, using Western blot, we investigated whether the inhibition was due to the interference on activation of NF-κB. We found that both the tomato extract and ferulic acid presented inhibitory activity on the expression of TNF-α and IL-1β cytokine by inhibiting the activation of NF-κB. The current results suggest that tomatoes and ferulic acid may contribute to prevention of chronic inflammatory diseases.

  8. Direct relationship between levels of TNF-α expression and endothelial dysfunction in reperfusion injury

    OpenAIRE

    Zhang, Cuihua; Wu, Junxi; Xu, Xiangbin; Potter, Barry J.; Gao, Xue

    2010-01-01

    We previously found that myocardial ischemia/reperfusion (I/R) initiates expression of tumor necrosis factor-α (TNF) leading to coronary endothelial dysfunction. However, it is not clear whether there is a direct relationship between levels of TNF expression and endothelial dysfunction in reperfusion injury. We studied levels of TNF expression by using different transgenic animals expressing varying amounts of TNF in I/R. We crossed TNF overexpression (TNF++/++) with TNF knockout (TNF−/−) mic...

  9. Divergent pathways for TNF and C(2)-ceramide toxicity in HTC hepatoma cells.

    Science.gov (United States)

    Autelli, Riccardo; Ullio, Chiara; Prigione, Elisa; Crepaldi, Silvia; Schiavone, Nicola; Brunk, Ulf T; Capaccioli, Sergio; Baccino, Francesco M; Bonelli, Gabriella

    2009-07-01

    We previously showed that, in the rat hepatoma cell line HTC, TNF brings about a non-caspase-dependent, apoptosis-like process requiring NADPH oxidase activity, an iron-mediated pro-oxidant status, and a functional acidic vacuolar compartment. This process may thus involve mechanisms such as autophagy or relocation of lysosomal enzymes, perhaps secondary to the formation of ceramide by acidic sphingomyelinase. Here we investigated whether ceramide formation contributes to the apoptogenic process. HTC cells were found to be sensitive to exogenous ceramide and significantly protected against TNF by desipramine, an inhibitor of lysosomal acid sphingomyelinase. However, Bcl-2 transfection and Bcl-x(L) upregulation by dexamethasone significantly diminished the apoptogenic effect of ceramide but not that of TNF, suggesting that ceramide is not directly involved in TNF toxicity. Moreover, Bcl-x(L) silencing precluded dexamethasone-induced protection against ceramide and, by itself, induced massive death, demonstrating the strict dependence of HTC cells on Bcl-x(L) for survival also under standard culture conditions.

  10. On the Contribution of Curl-Free Current Patterns to the Ultimate Intrinsic Signal-to-Noise Ratio at Ultra-High Field Strength.

    Science.gov (United States)

    Pfrommer, Andreas; Henning, Anke

    2017-05-01

    The ultimate intrinsic signal-to-noise ratio (SNR) is a coil independent performance measure to compare different receive coil designs. To evaluate this benchmark in a sample, a complete electromagnetic basis set is required. The basis set can be obtained by curl-free and divergence-free surface current distributions, which excite linearly independent solutions to Maxwell's equations. In this work, we quantitatively investigate the contribution of curl-free current patterns to the ultimate intrinsic SNR in a spherical head-sized model at 9.4 T. Therefore, we compare the ultimate intrinsic SNR obtained with having only curl-free or divergence-free current patterns, with the ultimate intrinsic SNR obtained from a combination of curl-free and divergence-free current patterns. The influence of parallel imaging is studied for various acceleration factors. Moreover results for different field strengths (1.5 T up to 11.7 T) are presented at specific voxel positions and acceleration factors. The full-wave electromagnetic problem is analytically solved using dyadic Green's functions. We show, that at ultra-high field strength (B 0 ⩾7T) a combination of curl-free and divergence-free current patterns is required to achieve the best possible SNR at any position in a spherical head-sized model. On 1.5- and 3T platforms, divergence-free current patterns are sufficient to cover more than 90% of the ultimate intrinsic SNR. Copyright © 2017 John Wiley & Sons, Ltd.

  11. A second CRM1-dependent nuclear export signal in the influenza A virus NS2 protein contributes to the nuclear export of viral ribonucleoproteins.

    Science.gov (United States)

    Huang, Shengping; Chen, Jingjing; Chen, Quanjiao; Wang, Huadong; Yao, Yanfeng; Chen, Jianjun; Chen, Ze

    2013-01-01

    Influenza A virus NS2 protein, also called nuclear export protein (NEP), is crucial for the nuclear export of viral ribonucleoproteins. However, the molecular mechanisms of NEP mediation in this process remain incompletely understood. A leucine-rich nuclear export signal (NES2) in NEP, located at the predicted N2 helix of the N-terminal domain, was identified in the present study. NES2 was demonstrated to be a transferable NES, with its nuclear export activity depending on the nuclear export receptor chromosome region maintenance 1 (CRM1)-mediated pathway. The interaction between NEP and CRM1 is coordinately regulated by both the previously reported NES (NES1) and now the new NES2. Deletion of the NES1 enhances the interaction between NEP and CRM1, and deletion of the NES1 and NES2 motifs completely abolishes this interaction. Moreover, NES2 interacts with CRM1 in the mammalian two-hybrid system. Mutant viruses containing NES2 alterations generated by reversed genetics exhibit reduced viral growth and delay in the nuclear export of viral ribonucleoproteins (vRNPs). The NES2 motif is highly conserved in the influenza A and B viruses. The results demonstrate that leucine-rich NES2 is involved in the nuclear export of vRNPs and contributes to the understanding of nucleocytoplasmic transport of influenza virus vRNPs.

  12. Glucagon-like Peptide-1 receptor signaling in the lateral parabrachial nucleus contributes to the control of food intake and motivation to feed.

    Science.gov (United States)

    Alhadeff, Amber L; Baird, John-Paul; Swick, Jennifer C; Hayes, Matthew R; Grill, Harvey J

    2014-08-01

    Central glucagon-like peptide-1 receptor (GLP-1R) activation reduces food intake and the motivation to work for food, but the neurons and circuits mediating these effects are not fully understood. Although lateral parabrachial nucleus (lPBN) neurons are implicated in the control of food intake and reward, the specific role of GLP-1R-expressing lPBN neurons is unexplored. Here, neuroanatomical tracing, immunohistochemical, and behavioral/pharmacological techniques are used to test the hypothesis that lPBN neurons contribute to the anorexic effect of central GLP-1R activation. Results indicate that GLP-1-producing neurons in the nucleus tractus solitarius project monosynaptically to the lPBN, providing a potential endogenous mechanism by which lPBN GLP-1R signaling may exert effects on food intake control. Pharmacological activation of GLP-1R in the lPBN reduced food intake, and conversely, antagonism of GLP-1R in the lPBN increased food intake. In addition, lPBN GLP-1R activation reduced the motivation to work for food under a progressive ratio schedule of reinforcement. Taken together, these data establish the lPBN as a novel site of action for GLP-1R-mediated control of food intake and reward.

  13. Tumour necrosis factor alpha (TNF-α) genetic polymorphisms and ...

    Indian Academy of Sciences (India)

    2Department of Occupational Health and Environmental Health, School of Public Health at Guangxi Medical University,. Nanning, Guangxi 530021, People's Republic of China. Abstract. Epidemiological studies have evaluated the association between tumour necrosis factor alpha (TNF-α)-308G/A and (TNF-α)-. 238G/A ...

  14. Kadar TNF-α dalam Zalir Peritoneal Penderita Endometriosis

    Directory of Open Access Journals (Sweden)

    TEDJA DANUDJA OEPOMO

    2005-11-01

    Full Text Available The aim of this research was to expose the role of tumor necrotic factor alpha (TNF-α in the pathogenetic endometriosis. This research had been done in dr. Muwardi Hospital Surakarta. Twenty patients undergoing laparoscopic operation because of endometriosis indication (Group I, 20 women (aged 23 to 40 who undergo interval sterilization by means of laparoscopic technique (Group II. During laparoscopic operation, peritoneal fluid is taken to examine TNF-α by ELISA technique. The results indicated that by independent t-test, a significant difference of concentration of TNF-α in the peritoneal fluid is found between endometriosis patients and normal women (who are sterilized (P=0.00. By chi-square test, the Ratio Odds value 171 shows that the high concentration of TNF-α will increase the possibility of endometriosis 171 times rather than the low TNF-α. It could be concluded the high concentration of TNF-α is the risk factor of endometriosis in comparison with the low TNF-α. It shows that quite possibly TNF-α has a role in the pathogenic endometriosis.

  15. Dichotomal role of TNF in experimental pulmonary edema reabsorption

    NARCIS (Netherlands)

    Braun, C; Hamacher, J; Morel, DR; Wendel, A; Lucas, R

    2005-01-01

    Distinct from its receptor binding sites, TNF carries a lectin-like domain, situated at the tip of the molecule, which specifically binds oligosaccharides, such as NN'-diacetylchitobiose. In view of the apparently conflicting data concerning TNF actions in pulmonary edema, we investigated the

  16. Decreased TNF Levels and Improved Retinal Ganglion Cell Survival in MMP-2 Null Mice Suggest a Role for MMP-2 as TNF Sheddase

    Directory of Open Access Journals (Sweden)

    Lies De Groef

    2015-01-01

    Full Text Available Matrix metalloproteinases (MMPs have been designated as both friend and foe in the central nervous system (CNS: while being involved in many neurodegenerative and neuroinflammatory diseases, their actions appear to be indispensable to a healthy CNS. Pathological conditions in the CNS are therefore often related to imbalanced MMP activities and disturbances of the complex MMP-dependent protease network. Likewise, in the retina, various studies in animal models and human patients suggested MMPs to be involved in glaucoma. In this study, we sought to determine the spatiotemporal expression profile of MMP-2 in the excitotoxic retina and to unravel its role during glaucoma pathogenesis. We reveal that intravitreal NMDA injection induces MMP-2 expression to be upregulated in the Müller glia. Moreover, MMP-2 null mice display attenuated retinal ganglion cell death upon excitotoxic insult to the retina, which is accompanied by normal glial reactivity, yet reduced TNF levels. Hence, we propose a novel in vivo function for MMP-2, as an activating sheddase of tumor necrosis factor (TNF. Given the pivotal role of TNF as a proinflammatory cytokine and neurodegeneration-exacerbating mediator, these findings generate important novel insights into the pathological processes contributing to glaucomatous neurodegeneration and into the interplay of neuroinflammation and neurodegeneration in the CNS.

  17. TNF-α Modulation of Intestinal Tight Junction Permeability Is Mediated by NIK/IKK-α Axis Activation of the Canonical NF-κB Pathway

    Science.gov (United States)

    Al-Sadi, Rana; Guo, Shuhong; Ye, Dongmei; Rawat, Manmeet; Ma, Thomas Y.

    2017-01-01

    Tumor necrosis factor (TNF)-α, a key mediator of intestinal inflammation, causes an increase in intestinal epithelial tight junction (TJ) permeability by activating myosin light chain kinase (MLCK; official name MYLK3) gene. However, the precise signaling cascades that mediate the TNF-α–induced activation of MLCK gene and increase in TJ permeability remain unclear. Our aims were to delineate the upstream signaling mechanisms that regulate the TNF-α modulation of intestinal TJ barrier function with the use of in vitro and in vivo intestinal epithelial model systems. TNF-α caused a rapid activation of both canonical and noncanonical NF-κB pathway. NF-κB–inducing kinase (NIK) and mitogen-activated protein kinase kinase-1 (MEKK-1) were activated in response to TNF-α. NIK mediated the TNF-α activation of inhibitory κB kinase (IKK)-α, and MEKK1 mediated the activation of IKK complex, including IKK-β. NIK/IKK-α axis regulated the activation of both NF-κB p50/p65 and RelB/p52 pathways. Surprisingly, the siRNA induced knockdown of NIK, but not MEKK-1, prevented the TNF-α activation of both NF-κB p50/p65 and RelB/p52 and the increase in intestinal TJ permeability. Moreover, NIK/IKK-α/NF-κB p50/p65 axis mediated the TNF-α–induced MLCK gene activation and the subsequent MLCK increase in intestinal TJ permeability. In conclusion, our data show that NIK/IKK-α/regulates the activation of NF-κB p50/p65 and plays an integral role in the TNF-α–induced activation of MLCK gene and increase in intestinal TJ permeability. PMID:26948423

  18. Co-inhibition of NF-κB and JNK is synergistic in TNF-expressing human AML

    Science.gov (United States)

    Volk, Andrew; Li, Jing; Xin, Junping; You, Dewen; Zhang, Jun; Liu, Xinli; Xiao, Yechen; Breslin, Peter; Li, Zejuan; Wei, Wei; Schmidt, Rachel; Li, Xingyu; Zhang, Zhou; Kuo, Paul C.; Nand, Sucha; Zhang, Jianke; Chen, Jianjun

    2014-01-01

    Leukemic stem cells (LSCs) isolated from acute myeloid leukemia (AML) patients are more sensitive to nuclear factor κB (NF-κB) inhibition-induced cell death when compared with hematopoietic stem and progenitor cells (HSPCs) in in vitro culture. However, inadequate anti-leukemic activity of NF-κB inhibition in vivo suggests the presence of additional survival/proliferative signals that can compensate for NF-κB inhibition. AML subtypes M3, M4, and M5 cells produce endogenous tumor necrosis factor α (TNF). Although stimulating HSPC with TNF promotes necroptosis and apoptosis, similar treatment with AML cells (leukemic cells, LCs) results in an increase in survival and proliferation. We determined that TNF stimulation drives the JNK–AP1 pathway in a manner parallel to NF-κB, leading to the up-regulation of anti-apoptotic genes in LC. We found that we can significantly sensitize LC to NF-κB inhibitor treatment by blocking the TNF–JNK–AP1 signaling pathway. Our data suggest that co-inhibition of both TNF–JNK–AP1 and NF-κB signals may provide a more comprehensive treatment paradigm for AML patients with TNF-expressing LC. PMID:24842373

  19. Tumour necrosis factor-alpha (TNF), lymphotoxin and TNF receptor levels in serum from patients with Wegener's granulomatosis

    DEFF Research Database (Denmark)

    Jónasdóttir, O; Petersen, J; Bendtzen, K

    2001-01-01

    Wegener's granulomatosis (WG) is a systemic inflammatory disease with vasculitis as the key feature. Abnormal expression of tumour necrosis factor alpha (TNFalpha) is considered of prime pathogenic importance in several inflammatory diseases. The effects of TNFa are mediated by TNF receptors (TNF...

  20. The antibody response against human and chimeric anti-TNF therapeutic antibodies primarily targets the TNF binding region

    NARCIS (Netherlands)

    van Schie, K. A.; Hart, M. H.; de Groot, E. R.; Kruithof, S.; Aarden, L. A.; Wolbink, G. J.; Rispens, T.

    2015-01-01

    In a subset of patients, anti tumour necrosis factor (TNF) therapeutic antibodies are immunogenic, resulting in the formation of antidrug antibodies (ADAs). Neutralising ADAs compete with TNF for its binding site and reduces the effective serum concentration, causing clinical non-response. It is

  1. TNF-α-induced depressive-like phenotype and p38(MAPK) activation are abolished by ascorbic acid treatment.

    Science.gov (United States)

    Moretti, Morgana; Budni, Josiane; Freitas, Andiara Espíndola; Neis, Vivian Binder; Ribeiro, Camille Mertins; de Oliveira Balen, Grasiela; Rieger, Débora Kurrle; Leal, Rodrigo Bainy; Rodrigues, Ana Lúcia S

    2015-06-01

    We investigated the effects of ascorbic acid on depressive-like behavior induced by tumor necrosis factor (TNF-α) in mice. Additionally, we examined the effects of combined administration of ascorbic acid and antidepressants, MK-801 and 7-nitroindazole in mice exposed or not to TNF-α and the capacity of TNF-α and ascorbic acid to modulate hippocampal and cerebrocortical phosphorylation of extracellular signal-regulated kinase (ERK), p38(MAPK) and c-Jun N-terminal kinase (JNK). In control animals, ascorbic acid reduced the immobility time in the tail suspension test (TST). Unilateral intracerebroventricular administration of TNF-α produced a depressive-like behavior in the TST, and the treatment with ascorbic acid prevented this effect. Sub-effective dose of ascorbic acid combined with sub-effective doses of fluoxetine, imipramine, bupropion, MK-801 or 7-nitroindazole produced a synergistic antidepressant-like effect in mice exposed or not to TNF-α. No treatment caused significant alterations in the locomotor activity of mice. Administration of TNF-α increased the phosphorylation of p38(MAPK) in hippocampus and cerebral cortex, and the treatment with ascorbic acid prevented this effect. Ascorbic acid increased phosphorylation of ERK1 in the hippocampus of saline- and TNF-α-treated animals, however it did not produce alterations in the cerebral cortex. No effects on phosphorylation of ERK2 or JNK were found. The observed effect of ascorbic acid seems to be associated, at least partially, with a reduced p38(MAPK) phosphorylation, activation of the monoaminergic systems as well as inhibition of N-methyl-D-aspartate (NMDA) receptors and nitric oxide (NO) synthesis. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

  2. TNF-α upregulates HIF-1α expression in pterygium fibroblasts and enhances their susceptibility to VEGF independent of hypoxia.

    Science.gov (United States)

    Kim, Kyoung Woo; Lee, Soo Jin; Kim, Jae Chan

    2017-11-01

    The clinical manifestations of pterygium are characterized by rapid growth and postoperative recurrences. We had previously proposed that hypoxia-inducible factor (HIF)-1α recruits progenitor cells during the development and progression of pterygia. Recently, it was reported that various stimuli, including inflammation, could activate HIF-1α even under normoxic conditions. The ocular surface directly faces external environments, and is thus frequently exposed to inflammatory insults. First, we examined the gene expression of HIF-1α, its downstream molecule, vascular endothelial growth factor (VEGF)-A, and VEGF receptor (VEGFR)-2 in corneal and conjunctival cells compared with cultured human umbilical vein endothelial cells. Corneal fibroblasts had high expression of VEGFR-2 in the presence of TNF-α, and HIF-1α was activated by TNF-α in diverse ocular surface cells. The HIF-1α/VEGF/VEGFR signaling pathway in response to TNF-α was evaluated in cultured human pterygium fibroblasts (HPFs) at the gene and protein levels and was compared to treatment with cobalt chloride (CoCl 2 ), a hypoxic mimetic, to exclude the effect of hypoxia. Although VEGF-A expression was not changed by TNF-α, expression of HIF-1α and VEGFR-2 was enhanced in HPFs treated with TNF-α, independent of hypoxia conditioning. In addition, VEGF-C gene expression was activated solely by TNF-α in HPF, but VEGF-B levels were not significantly affected. These results may provide mechanistic explanations for the uniquely vigorous proliferation of pterygium fibrovascular tissue during TNF-α-induced ocular surface inflammation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Molecular mechanisms underlying mancozeb-induced inhibition of TNF-alpha production

    International Nuclear Information System (INIS)

    Corsini, Emanuela; Viviani, Barbara; Birindelli, Sarah; Gilardi, Federica; Torri, Anna; Codeca, Ilaria; Lucchi, Laura; Bartesaghi, Stefano; Galli, Corrado L.; Marinovich, Marina; Colosio, Claudio

    2006-01-01

    Mancozeb, a polymeric complex of manganese ethylenebisdithiocarbamate with zinc salt, is widely used in agriculture as fungicide. Literature data indicate that ethylenebisdithiocarbamates (EBDTCs) may have immunomodulatory effects in humans. We have recently found in agricultural workers occupationally exposed to the fungicide mancozeb a statistically significant decrease in lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF) production in leukocytes. TNF is an essential proinflammatory cytokine whose production is normally stimulated during an infection. The purpose of this work was to establish an in vitro model reflecting in vivo data and to characterize the molecular mechanism of action of mancozeb. The human promyelocytic cell line THP-1 was used as in vitro model to study the effects of mancozeb and its main metabolite ethylenthiourea (ETU) on LPS-induced TNF release. Mancozeb, but not ETU, at non-cytotoxic concentrations (1-100 μg/ml), induced a dose- and time-dependent inhibition of LPS-induced TNF release, reflecting in vivo data. The modulatory effect observed was not limited to mancozeb but also other EBDTCs, namely zineb and ziram, showed similar inhibitory effects. Mancozeb must be added before or simultaneously to LPS in order to observe the effect, indicating that it acts on early events triggered by LPS. It is known that nuclear factor-κB (NF-κB) tightly regulates TNF transcription. We could demonstrate that mancozeb, modulating LPS-induced reactive oxygen species generation, prevented IκB degradation and NF-κB nuclear translocation, which in turn resulted in decreased TNF production. To further understand the mechanism of the effect of mancozeb on TNF transcription, THP-1 cells were transfected with NF-κB promoter-luciferase construct, and the effect of mancozeb on luciferase activity was measured. Cells transfected with promoter constructs containing κB site showed decreased LPS-induced luciferase activity relative to control

  4. The MNK–eIF4E Signaling Axis Contributes to Injury-Induced Nociceptive Plasticity and the Development of Chronic Pain

    Science.gov (United States)

    Asiedu, Marina N.; Megat, Salim; Burton, Michael D.; Burgos-Vega, Carolina C.; Melemedjian, Ohannes K.; Boitano, Scott; Vagner, Josef; Pancrazio, Joseph J.; Mogil, Jeffrey S.; Dussor, Gregory

    2017-01-01

    Injury-induced sensitization of nociceptors contributes to pain states and the development of chronic pain. Inhibiting activity-dependent mRNA translation through mechanistic target of rapamycin and mitogen-activated protein kinase (MAPK) pathways blocks the development of nociceptor sensitization. These pathways convergently signal to the eukaryotic translation initiation factor (eIF) 4F complex to regulate the sensitization of nociceptors, but the details of this process are ill defined. Here we investigated the hypothesis that phosphorylation of the 5′ cap-binding protein eIF4E by its specific kinase MAPK interacting kinases (MNKs) 1/2 is a key factor in nociceptor sensitization and the development of chronic pain. Phosphorylation of ser209 on eIF4E regulates the translation of a subset of mRNAs. We show that pronociceptive and inflammatory factors, such as nerve growth factor (NGF), interleukin-6 (IL-6), and carrageenan, produce decreased mechanical and thermal hypersensitivity, decreased affective pain behaviors, and strongly reduced hyperalgesic priming in mice lacking eIF4E phosphorylation (eIF4ES209A). Tests were done in both sexes, and no sex differences were found. Moreover, in patch-clamp electrophysiology and Ca2+ imaging experiments on dorsal root ganglion neurons, NGF- and IL-6-induced increases in excitability were attenuated in neurons from eIF4ES209A mice. These effects were recapitulated in Mnk1/2−/− mice and with the MNK1/2 inhibitor cercosporamide. We also find that cold hypersensitivity induced by peripheral nerve injury is reduced in eIF4ES209A and Mnk1/2−/− mice and following cercosporamide treatment. Our findings demonstrate that the MNK1/2–eIF4E signaling axis is an important contributing factor to mechanisms of nociceptor plasticity and the development of chronic pain. SIGNIFICANCE STATEMENT Chronic pain is a debilitating disease affecting approximately one in three Americans. Chronic pain is thought to be driven by changes in

  5. Increased Serotonin Signaling Contributes to the Warburg Effect in Pancreatic Tumor Cells Under Metabolic Stress and Promotes Growth of Pancreatic Tumors in Mice.

    Science.gov (United States)

    Jiang, Shu-Heng; Li, Jun; Dong, Fang-Yuan; Yang, Jian-Yu; Liu, De-Jun; Yang, Xiao-Mei; Wang, Ya-Hui; Yang, Min-Wei; Fu, Xue-Liang; Zhang, Xiao-Xin; Li, Qing; Pang, Xiu-Feng; Huo, Yan-Miao; Li, Jiao; Zhang, Jun-Feng; Lee, Ho-Young; Lee, Su-Jae; Qin, Wen-Xin; Gu, Jian-Ren; Sun, Yong-Wei; Zhang, Zhi-Gang

    2017-07-01

    Desmoplasia and poor vascularity cause severe metabolic stress in pancreatic ductal adenocarcinomas (PDACs). Serotonin (5-HT) is a neuromodulator with neurotransmitter and neuroendocrine functions that contributes to tumorigenesis. We investigated the role of 5-HT signaling in the growth of pancreatic tumors. We measured the levels of proteins that regulate 5-HT synthesis, packaging, and degradation in pancreata from Kras G12D/+ /Trp53 R172H/+ /Pdx1-Cre (KPC) mice, which develop pancreatic tumors, as well as in PDAC cell lines and a tissue microarray containing 81 human PDAC samples. We also analyzed expression levels of proteins involved in 5-HT synthesis and degradation by immunohistochemical analysis of a tissue microarray containing 311 PDAC specimens, and associated expression levels with patient survival times. 5-HT level in 14 matched PDAC tumor and non-tumor tissues were analyzed by ELISA. PDAC cell lines were incubated with 5-HT and cell survival and apoptosis were measured. We analyzed expression of the 5-HT receptor HTR2B in PDAC cells and effects of receptor agonists and antagonists, as well as HTR2B knockdown with small hairpin RNAs. We determined the effects of 5-HT stimulation on gene expression profiles of BxPC-3 cells. Regulation of glycolysis by 5-HT signaling via HTR2B was assessed by immunofluorescence and immunoprecipitation analyses, as well as by determination of the extracellular acid ratio, glucose consumption, and lactate production. Primary PDACs, with or without exposure to SB204741 (a selective antagonist of HTR2B), were grown as xenograft tumors in mice, and SB204741 was administered to tumor-bearing KPC mice; tumor growth and metabolism were measured by imaging analyses. In immunohistochemical analysis of a tissue microarray of PDAC specimens, increased levels of TPH1 and decreased level of MAOA, which regulate 5-HT synthesis and degradation, correlated with stage and size of PDACs and shorter patient survival time. We found levels

  6. Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.)

    Science.gov (United States)

    Liu, Yang; Wang, Tongli; El-Kassaby, Yousry A.

    2016-05-01

    Environmental signals are important triggers in the life-cycle transitions and play a crucial role in the life-history evolution. Yet very little is known about the leading ecological factors contributing to the variations of life-history traits in perennial plants. This paper explores both the causes and consequences for the evolution of life-history traits (i.e., seed dormancy and size) in lodgepole pine (Pinus contorta Dougl.) across British Columbia (B.C.), Canada. We selected 83 logepole pine populations covering 22 ecosystem zones of B.C. and through their geographic coordinate, 197 climatic variables were generated accordingly for the reference (1961-1990) and future (2041-2070) periods. We found that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations and thus provide reliable predictors in response to global climate change. Evapotranspiration and precipitation in the plant-to-seed chronology are the most critical climate variables for seed dormancy and size variations, respectively. Hence, we predicted that levels of seed dormancy in lodgepole pine would increase across large tracts of B.C. in 2050s. Winter-chilling is able to increase the magnitude of life-history plasticity and lower the bet-hedge strategy in the seed-to-plant transition; however, winter-chilling is likely to be insufficient in the north of 49° N in 2050s, which may delay germination while unfavorable conditions during dry summers may result in adverse consequences in the survival of seedlings owing to extended germination span. These findings provide useful information to studies related to assessments of seed transfer and tree adaptation.

  7. La sobreexpresión de RAC3 es una señal transformante y proliferativa que contribuye al desarrollo tumoral RAC3 overexpression is a transforming and proliferative signal that contributes to tumoral development

    Directory of Open Access Journals (Sweden)

    Cecilia V. Alvarado

    2011-02-01

    to apoptosis. In this work, we investigated if there are any additional mechanisms by which RAC3 may contribute to tumor development and if TNF-a, an inflammatory cytokine that is found at high levels in cancer could increase RAC3 levels. We found that enhancement of RAC3 levels by transfection of HEK293 cells with a RAC3 expression vector induces a significant increase of cell proliferation not only in the presence, but also in the absence of serum growth factors. Moreover, the cells were transformed showing an anchorage independent growth, similar to that observed in tumoral cells. The treatment of HEK293 cells with TNF-a induced an increase in the protein levels of RAC3 and this was blocked by an NF-?B specific inhibitor, suggesting that this transcription factor is involved in the cytokine effect. We conclude that RAC3, in addition to is anti-apoptotic action, is a transforming factor that promotes the proliferation and growth independent of anchorage, and that its levels could be elevated by the action of inflammatory cytokines that are involved in the anti-tumoral response.

  8. Effects of TNF-α blocking on experimental periodontitis and type 2 diabetes in obese diabetic Zucker rats.

    Science.gov (United States)

    Grauballe, Morten Bay; Østergaard, Jakob Appel; Schou, Søren; Flyvbjerg, Allan; Holmstrup, Palle

    2015-09-01

    Tumour necrosis factor α (TNF-α) is considered a key signalling modulator in the pathogenesis of both periodontitis (PD) and type 2 diabetes mellitus (DM2). This study aims at elucidating the effect of TNF-α blocking on the interplay between PD and DM2. Obese diabetic Zucker rats and their lean littermates were divided into five treatment groups with or without periodontitis. Anti-TNF-α treatment was provided with Etanercept injections. Diabetic state was evaluated by oral glucose tolerance test, the homeostatic model assessment, free fatty acids and blood glucose. Systemic inflammation was assessed by measurement of interleukin (IL)-1β, IL-6 and TNF-α in plasma. Kidney complications were evaluated by real-time rtPCR, creatinine clearance rate, urinary albumin excretion and increase in weight. PD was evaluated by registration of alveolar bone level. After 4 weeks the diabetic state was modified by Etanercept treatment with lower insulin levels and lower homeostatic model assessment. Furthermore, while kidney complications were reduced by Etanercept treatment, PD had no effect. PD was influenced by diabetic state, but the impact was attenuated by Etanercept treatment. In this study anti-TNF-α treatment improved glucose tolerance and compensated for the increased periodontal disease in obese diabetic Zucker. PD did not influence diabetic parameters assessed including complications of the rats kidneys. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Claudin-1 promotes TNF-α-induced epithelial-mesenchymal transition and migration in colorectal adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Ajaz A. [Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Ahmad, Rizwan; Uppada, SrijayaPrakash B. [Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Singh, Amar B. [From the Department of Veterans Affairs, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Dhawan, Punita, E-mail: punita.dhawan@unmc.edu [From the Department of Veterans Affairs, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68022 (United States)

    2016-11-15

    Epithelial-mesenchymal transition (EMT) is an important mechanism in cancer progression and malignancy including colorectal cancer (CRC). Importantly, inflammatory mediators are critical constituents of the local tumor environment and an intimate link between CRC progression and inflammation is now validated. We and others have reported key role of the deregulated claudin-1 expression in colon carcinogenesis including colitis-associated colon cancer (CAC). However, the causal association between claudin-1 expression and inflammation-induced colon cancer progression remains unclear. Here we demonstrate, TNF-α, a pro-inflammatory cytokine, regulates claudin-1 to modulate epithelial to mesenchymal transition (EMT) and migration in colon adenocarcinoma cells. Importantly, colon cancer cells cultured in the presence of TNF-α (10 ng/ml), demonstrated a sharp decrease in E-cadherin expression and an increase in vimentin expression (versus control cells). Interestingly, TNF-α treatment also upregulated (and delocalized) claudin-1 expression in a time-dependent manner accompanied by increase in proliferation and wound healing. Furthermore, similar to our previous observation that claudin-1 overexpression in CRC cells induces ERK1/2 and Src- activation, signaling associated with colon cancer cell survival and transformation, TNF-α-treatment induced upregulation of phospho-ERK1/2 and -Src expression. The shRNA-mediated inhibition of claudin-1 expression largely abrogated the TNF-α-induced changes in EMT, proliferation, migration, p-Erk and p-Src expression. Taken together, our data demonstrate TNF-α mediated regulation of claudin-1 and tumorigenic abilities of colon cancer cells and highlights a key role of deregulated claudin-1 expression in inflammation-induced colorectal cancer growth and progression, through the regulation of the ERK and Src-signaling.

  10. Claudin-1 promotes TNF-α-induced epithelial-mesenchymal transition and migration in colorectal adenocarcinoma cells

    International Nuclear Information System (INIS)

    Bhat, Ajaz A.; Ahmad, Rizwan; Uppada, SrijayaPrakash B.; Singh, Amar B.; Dhawan, Punita

    2016-01-01

    Epithelial-mesenchymal transition (EMT) is an important mechanism in cancer progression and malignancy including colorectal cancer (CRC). Importantly, inflammatory mediators are critical constituents of the local tumor environment and an intimate link between CRC progression and inflammation is now validated. We and others have reported key role of the deregulated claudin-1 expression in colon carcinogenesis including colitis-associated colon cancer (CAC). However, the causal association between claudin-1 expression and inflammation-induced colon cancer progression remains unclear. Here we demonstrate, TNF-α, a pro-inflammatory cytokine, regulates claudin-1 to modulate epithelial to mesenchymal transition (EMT) and migration in colon adenocarcinoma cells. Importantly, colon cancer cells cultured in the presence of TNF-α (10 ng/ml), demonstrated a sharp decrease in E-cadherin expression and an increase in vimentin expression (versus control cells). Interestingly, TNF-α treatment also upregulated (and delocalized) claudin-1 expression in a time-dependent manner accompanied by increase in proliferation and wound healing. Furthermore, similar to our previous observation that claudin-1 overexpression in CRC cells induces ERK1/2 and Src- activation, signaling associated with colon cancer cell survival and transformation, TNF-α-treatment induced upregulation of phospho-ERK1/2 and -Src expression. The shRNA-mediated inhibition of claudin-1 expression largely abrogated the TNF-α-induced changes in EMT, proliferation, migration, p-Erk and p-Src expression. Taken together, our data demonstrate TNF-α mediated regulation of claudin-1 and tumorigenic abilities of colon cancer cells and highlights a key role of deregulated claudin-1 expression in inflammation-induced colorectal cancer growth and progression, through the regulation of the ERK and Src-signaling.

  11. ADAMTS-7 Exhibits Elevated Expression in Cartilage of Osteonecrosis of Femoral Head and Has a Positive Correlation with TNF-α and NF-κB P65

    Directory of Open Access Journals (Sweden)

    Jing-kun Li

    2015-01-01

    Full Text Available ADAMTS-7 has been reported to exaggerate cartilage degeneration and to be associated with TNF-α and NF-κB signaling pathway. In this study we compared the expression of ADAMTS-7, TNF-α, and Phospho-NF-κB in patients with femoral neck fracture (FNF and osteonecrosis of femoral head (ONFH at different stages. We found that expression of ADAMTS-7, TNF-α, and Phospho-NF-κB was significantly upregulated in ONFH patients’ articular cartilage and related to the pathogenesis of ONFH. Thus we conclude that ADAMTS-7 level appears to be positively associated with expression of TNF-α and Phospho-NF-κB P65 in cartilage, which may imply its association with cartilage destruction of ONFH.

  12. Microglial TNF and IL-1 as early disease-modifiers in Alzheimer's-like disease in mice

    DEFF Research Database (Denmark)

    Ilkjær, Laura; Babcock, Alicia; Finsen, Bente

    2015-01-01

    In Alzheimer's disease (AD) signs of microglial activation is evident already in prodromal and early AD. This and other evidence suggest that neuroinflammation contributes to the progression of the early disease development in AD. Microglial cells have the capacity to produce cytokines such as TNF...... and IL-1, and to phagocytose and clear amyloid beta (As), however, the influence of TNF and IL-1, and inflammation in general, on these processes is still poorly understood. We have studied the development of As pathology, and basal and lipopolysaccharide (LPS) stimulated microglial cytokine production...... mice. Microglial expression of TNF and IL-1s can be significantly increased by i.p. injection of LPS, which we find reduces cortical As pathology at 12 months. Results will also be reported on the influence of IL-1 in modulating As pathology during early disease stages in APPswe/PS1DE9 mice. Together...

  13. Elevated Peritoneal Fluid TNF-α Incites Ovarian Early Growth Response Factor 1 Expression and Downstream Protease Mediators

    Science.gov (United States)

    Birt, Julie A.; Nabli, Henda; Stilley, Julie A.; Windham, Emma A.; Frazier, Shellaine R.

    2013-01-01

    Endometriosis-associated infertility manifests itself via multiple, poorly understood mechanisms. Our goal was to characterize signaling pathways, between peritoneal endometriotic lesions and the ovary, leading to failed ovulation. Genome-wide microarray analysis comparing ovarian tissue from an in vivo endometriosis model in the rat (Endo) with controls (Sham) identified 22 differentially expressed genes, including transiently expressed early growth response factor 1 (Egr1). The Egr1 regulates gene requisites for ovulation. The Egr1 promoter is responsive to tumor necrosis factor-alpha (TNF-α) signaling. We hypothesized that altered expression of ovarian EGR1 is induced by elevated peritoneal fluid TNF-α which is upregulated by the presence of peritoneal endometriosis. Endo rats, compared to controls, had more peritoneal fluid TNF-α and quantitative, spatial differences in Egr1 mRNA and EGR1 protein localization in follicular compartments. Interactions between elevated peritoneal fluid TNF-α and overexpression of follicular Egr1/EGR1 expression may affect downstream protease pathways impeding ovulation in endometriosis. Preliminary studies identified similar patterns of EGR1 protein localization in human ovaries from women with endometriosis and compared to those without endometriosis. PMID:23427178

  14. Taraxacum officinale induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

    Science.gov (United States)

    Koo, Hyun-Na; Hong, Seung-Heon; Song, Bong-Keun; Kim, Cheorl-Ho; Yoo, Young-Hyun; Kim, Hyung-Min

    2004-01-16

    Taraxacum officinale (TO) has been frequently used as a remedy for women's disease (e.g. breast and uterus cancer) and disorders of the liver and gallbladder. Several earlier studies have indicated that TO exhibits anti-tumor properties, but its mechanism remains to be elucidated. In this study, we investigated the effect of TO on the cytotoxicity and production of cytokines in human hepatoma cell line, Hep G2. Our results show that TO decreased the cell viability by 26%, and significantly increased the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha production compared with media control (about 1.6-fold for TNF-alpha, and 2.4-fold for IL-1alpha, P < 0.05). Also, TO strongly induced apoptosis of Hep G2 cells as determined by flow cytometry. Increased amounts of TNF-alpha and IL-1alpha contributed to TO-induced apoptosis. Anti-TNF-alpha and IL-1alpha antibodies almost abolished it. These results suggest that TO induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

  15. TNF-α stimulates endothelial palmitic acid transcytosis and promotes insulin resistance

    Science.gov (United States)

    Li, Wenjing; Yang, Xiaoyan; Zheng, Tao; Xing, Shasha; Wu, Yaogong; Bian, Fang; Wu, Guangjie; Li, Ye; Li, Juyi; Bai, Xiangli; Wu, Dan; Jia, Xiong; Wang, Ling; Zhu, Lin; Jin, Si

    2017-01-01

    Persistent elevation of plasma TNF-α is a marker of low grade systemic inflammation. Palmitic acid (PA) is the most abundant type of saturated fatty acid in human body. PA is bound with albumin in plasma and could not pass through endothelial barrier freely. Albumin-bound PA has to be transported across monolayer endothelial cells through intracellular transcytosis, but not intercellular diffusion. In the present study, we discovered that TNF-α might stimulate PA transcytosis across cardiac microvascular endothelial cells, which further impaired the insulin-stimulated glucose uptake by cardiomyocytes and promoted insulin resistance. In this process, TNF-α-stimulated endothelial autophagy and NF-κB signaling crosstalk with each other and orchestrate the whole event, ultimately result in increased expression of fatty acid transporter protein 4 (FATP4) in endothelial cells and mediate the increased PA transcytosis across microvascular endothelial cells. Hopefully the present study discovered a novel missing link between low grade systemic inflammation and insulin resistance. PMID:28304381

  16. Pre-Transplantation Blockade of TNF-α-Mediated Oxygen Species Accumulation Protects Hematopoietic Stem Cells.

    Science.gov (United States)

    Ishida, Takashi; Suzuki, Sachie; Lai, Chen-Yi; Yamazaki, Satoshi; Kakuta, Shigeru; Iwakura, Yoichiro; Nojima, Masanori; Takeuchi, Yasuo; Higashihara, Masaaki; Nakauchi, Hiromitsu; Otsu, Makoto

    2017-04-01

    Hematopoietic stem cell (HSC) transplantation (HSCT) for malignancy requires toxic pre-conditioning to maximize anti-tumor effects and donor-HSC engraftment. While this induces bone marrow (BM)-localized inflammation, how this BM environmental change affects transplanted HSCs in vivo remains largely unknown. We here report that, depending on interval between irradiation and HSCT, residence within lethally irradiated recipient BM compromises donor-HSC reconstitution ability. Both in vivo and in vitro we demonstrate that, among inflammatory cytokines, TNF-α plays a role in HSC damage: TNF-α stimulation leads to accumulation of reactive oxygen species (ROS) in highly purified hematopoietic stem/progenitor cells (HSCs/HSPCs). Transplantation of flow-cytometry-sorted murine HSCs reveals damaging effects of accumulated ROS on HSCs. Short-term incubation either with an specific inhibitor of tumor necrosis factor receptor 1 signaling or an antioxidant N-acetyl-L-cysteine (NAC) prevents TNF-α-mediated ROS accumulation in HSCs. Importantly, pre-transplantation exposure to NAC successfully demonstrats protective effects in inflammatory BM on graft-HSCs, exhibiting better reconstitution capability than that of nonprotected control grafts. We thus suggest that in vivo protection of graft-HSCs from BM inflammation is a feasible and attractive approach, which may lead to improved hematopoietic reconstitution kinetics in transplantation with myeloablative conditioning that inevitably causes inflammation in recipient BM. Stem Cells 2017;35:989-1002. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  17. Cocaine Induces Nuclear Export and Degradation of Neuronal Retinoid X Receptor-γ via a TNF-α/JNK-Mediated Mechanism

    Science.gov (United States)

    Kovalevich, Jane; Yen, William; Ozdemir, Ahmet; Langford, Dianne

    2015-01-01

    Cocaine abuse represents an immense societal health and economic burden for which no effective treatment currently exists. Among the numerous intracellular signaling cascades impacted by exposure to cocaine, increased and aberrant production of pro-inflammatory cytokines in the CNS has been observed. Additionally, we have previously reported a decrease in retinoid-X-receptor-gamma (RXR-γ) in brains of mice chronically exposed to cocaine. Through obligate heterodimerization with a number of nuclear receptors, RXRs serve as master regulatory transcription factors, which can potentiate or suppress expression of a wide spectrum of genes. Little is known about the regulation of RXR levels, but previous studies indicate cellular stressors such as cytokines negatively regulate levels of RXRs in vitro. To evaluate the mechanism underlying the cocaine-induced decreases in RXR-γ levels observed in vivo, we exposed neurons to cocaine in vitro and examined pathways which may contribute to disruption in RXR signaling, including activation of stress pathways by cytokine induction. In these studies, we provide the first evidence that cocaine exposure disrupts neuronal RXR-γ signaling in vitro by promoting its nuclear export and degradation. Furthermore, we demonstrate this effect may be mediated, at least in part, by cocaine-induced production of TNF-α and its downstream effector c-Jun-NH-terminal kinase (JNK). Findings from this study are therefore applicable to both cocaine abuse and to pathological conditions characterized by neuroinflammatory factors, such as neurodegenerative disease. PMID:25586717

  18. Anti-TNF-alpha antibody attenuates subarachnoid hemorrhage-induced apoptosis in the hypothalamus by inhibiting the activation of Erk

    Directory of Open Access Journals (Sweden)

    Ma L

    2018-02-01

    Full Text Available Ling Ma,1 Yong Jiang,2 Yanan Dong,2 Jun Gao,2 Bin Du,2 Dianwei Liu2 1Department of Clinical Laboratory, The Second Hospital of Shandong University, Jinan, Shandong, People’s Republic of China; 2Department of Neurosurgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, People’s Republic of China Background: Subarachnoid hemorrhage (SAH can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis. Materials and methods: SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk and Erk. Finally, anxiety-like behavior was identified by using open field. Results: Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH

  19. TRADD, TRAF2, RIP1 and TAK1 are required for TNF-α-induced pro-labour mediators in human primary myometrial cells.

    Science.gov (United States)

    Lim, Ratana; Barker, Gillian; Lappas, Martha

    2017-07-01

    TNF-α plays a central role in the processes of human labour and delivery. This study sought to determine the role of the adaptor proteins TNFR1-associated death domain protein (TRADD), TNF receptor-associated factor 2 (TRAF2), receptor interacting protein 1 (RIP1) and transforming growth factor beta-activated kinase 1 (TAK1) in TNF-α-induced formation of pro-labour mediators. Human primary myometrial cells were transfected with siRNA against TRADD (siTRADD), TRAF2 (siTRAF2), RIP1 (siRIP1) or TAK1 (siTAK1), treated with TNF-α, and assayed for pro-inflammatory mediators expression. siTRADD, siTRAF2, siRIP1 and siTAK1 significantly decreased TNF-α-induced IL-1α, IL-1β, IL-6, IL-8, MCP-1 mRNA expression and release of IL-6, IL-8 and MCP-1; and cyclooxygenase (COX)-2 expression and release of prostaglandin PGF 2α . There was a significant attenuation of TNF-α-induced expression of adhesion molecules ICAM-1 and VCAM-1 mRNA with siTRADD, siTRAF2 or siRIP1. siTRADD and siRIP1 significantly attenuated TNF-α-induced MMP-9 mRNA expression and release and nuclear factor κB (NF-κB) transcriptional activity. There was a significant increase in TNF-α-induced sVCAM-1 release, MMP-9 mRNA expression and NF-κB activity with siTAK1. TRADD, TRAF2, RIP1 and TAK1 are involved in TNFsignalling in human myometrium. Further studies are required to determine whether inhibition of these proteins can prevent preterm birth. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. TNF-alpha, leptin, and lymphocyte function in human aging

    DEFF Research Database (Denmark)

    Bruunsgaard, H.; Pedersen, Agnes Nadelmann; Schroll, M.

    2000-01-01

    Aging is associated with increased inflammatory activity and concomitant decreased T cell mediated immune responses. Leptin may provide a link between inflammation and T cell function in aging. The aim of the study was to investigate if plasma levels of tumor necrosis factor (TNF)-alpha were...... there was no difference with regard to IL-2 production. Furthermore, there were no age-related differences in serum levels of leptin, However, women had higher levels than men. In the elderly people, serum levels of leptin were correlated with TNF-alpha in univariate regression analysis and in a multiple linear...... regression analysis adjusting for the effect of gender and body mass index. Furthermore, TNF-alpha, but not leptin, was positively correlated to sIL-2R and negatively correlated to IL-2 production. In conclusion, increased plasma levels of TNF-alpha in aging is associated with poor IL-2 production ex vivo...

  1. Skeletal muscle cells possess a 'memory' of acute early life TNF-α exposure: role of epigenetic adaptation.

    Science.gov (United States)

    Sharples, Adam P; Polydorou, Ioanna; Hughes, David C; Owens, Daniel J; Hughes, Thomas M; Stewart, Claire E

    2016-06-01

    Sufficient quantity and quality of skeletal muscle is required to maintain lifespan and healthspan into older age. The concept of skeletal muscle programming/memory has been suggested to contribute to accelerated muscle decline in the elderly in association with early life stress such as fetal malnutrition. Further, muscle cells in vitro appear to remember the in vivo environments from which they are derived (e.g. cancer, obesity, type II diabetes, physical inactivity and nutrient restriction). Tumour-necrosis factor alpha (TNF-α) is a pleiotropic cytokine that is chronically elevated in sarcopenia and cancer cachexia. Higher TNF-α levels are strongly correlated with muscle loss, reduced strength and therefore morbidity and earlier mortality. We have extensively shown that TNF-α impairs regenerative capacity in mouse and human muscle derived stem cells [Meadows et al. (J Cell Physiol 183(3):330-337, 2000); Foulstone et al. (J Cell Physiol 189(2):207-215, 2001); Foulstone et al. (Exp Cell Res 294(1):223-235, 2004); Stewart et al. (J Cell Physiol 198(2):237-247, 2004); Al-Shanti et al. (Growth factors (Chur, Switzerland) 26(2):61-73, 2008); Saini et al. (Growth factors (Chur, Switzerland) 26(5):239-253, 2008); Sharples et al. (J Cell Physiol 225(1):240-250, 2010)]. We have also recently established an epigenetically mediated mechanism (SIRT1-histone deacetylase) regulating survival of myoblasts in the presence of TNF-α [Saini et al. (Exp Physiol 97(3):400-418, 2012)]. We therefore wished to extend this work in relation to muscle memory of catabolic stimuli and the potential underlying epigenetic modulation of muscle loss. To enable this aim; C2C12 myoblasts were cultured in the absence or presence of early TNF-α (early proliferative lifespan) followed by 30 population doublings in the absence of TNF-α, prior to the induction of differentiation in low serum media (LSM) in the absence or presence of late TNF-α (late proliferative lifespan). The cells that

  2. β2-adrenergic agonists modulate TNF-α induced astrocytic inflammatory gene expression and brain inflammatory cell populations

    Science.gov (United States)

    2014-01-01

    Background The NF-κB signaling pathway orchestrates many of the intricate aspects of neuroinflammation. Astrocytic β2-adrenergic receptors have emerged as potential regulators in central nervous system inflammation and are potential targets for pharmacological modulation. The aim of this study was to elucidate the crosstalk between astrocytic β2-adrenergic receptors and the TNF-α induced inflammatory gene program. Methods Proinflammatory conditions were generated by the administration of TNF-α. Genes that are susceptible to astrocytic crosstalk between β2-adrenergic receptors (stimulated by clenbuterol) and TNF-α were identified by qPCR-macroarray-based gene expression analysis in a human 1321 N1 astrocytoma cell line. Transcriptional patterns of the identified genes in vitro were validated by RT-PCR on the 1321 N1 cell line as well as on primary rat astrocytes. In vivo expression patterns were examined by intracerebroventricular administration of clenbuterol and/or TNF-α in rats. To examine the impact on the inflammatory cell content of the brain we performed extensive FACS analysis of rat brain immune cells after intracerebroventricular clenbuterol and/or TNF-α administration. Results Parallel transcriptional patterns in vivo and in vitro confirmed the relevance of astrocytic β2-adrenergic receptors as modulators of brain inflammatory responses. Importantly, we observed pronounced effects of β2-adrenergic receptor agonists and TNF-α on IL-6, CXCL2, CXCL3, VCAM1, and ICAM1 expression, suggesting a role in inflammatory brain cell homeostasis. Extensive FACS-analysis of inflammatory cell content in the brain demonstrated that clenbuterol/TNF-α co-administration skewed the T cell population towards a double negative phenotype and induced a shift in the myeloid brain cell population towards a neutrophilic predominance. Conclusions Our results show that astrocytic β2-adrenergic receptors are potent regulators of astrocytic TNF-α-activated genes in

  3. Sensitization of TNF-induced cytotoxicity in lung cancer cells by concurrent suppression of the NF-κB and Akt pathways

    International Nuclear Information System (INIS)

    Wang Xia; Chen Wenshu; Lin Yong

    2007-01-01

    Blockage of either nuclear factor-κB (NF-κB) or Akt sensitizes cancer cells to TNF-induced apoptosis. In this study, we investigated the undetermined effect of concurrent blockage of these two survival pathways on TNF-induced cytotoxicity in lung cancer cells. The results show that Akt contributes to TNF-induced NF-κB activation in lung cancer cells through regulating phosphorylation of the p65/RelA subunit of NF-κB. Although individually blocking IKK or Akt partially suppressed TNF-induced NF-κB activation, concurrent suppression of these pathways completely inhibited TNF-induced NF-κB activation and downstream anti-apoptotic gene expression, and synergistically potentiated TNF-induced cytotoxicity. Moreover, suppression of Akt inhibited the Akt-mediated anti-apoptotic pathway through dephosphorylation of BAD. These results indicate that concurrent suppression of NF-κB and Akt synergistically sensitizes TNF-induced cytotoxicity through blockage of distinct survival pathways downstream of NF-κB and Akt, which may be applied in lung cancer therapy

  4. Safety of TNF-α inhibitors during IBD pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Loftus, Edward V; Jess, Tine

    2013-01-01

    Tumor necrosis factor (TNF)-alpha inhibitors are increasingly being used in inflammatory bowel disease (IBD). Because this chronic intestinal disorder often affects women of fertile age, it is essential to assess the effect of biologics on pregnancy outcome.......Tumor necrosis factor (TNF)-alpha inhibitors are increasingly being used in inflammatory bowel disease (IBD). Because this chronic intestinal disorder often affects women of fertile age, it is essential to assess the effect of biologics on pregnancy outcome....

  5. Uncaria tomentosa acts as a potent TNF-alpha inhibitor through NF-kappaB.

    Science.gov (United States)

    Allen-Hall, Lisa; Arnason, John T; Cano, Pablo; Lafrenie, Robert M

    2010-02-17

    Uncaria tomentosa, commonly known as Cat's Claw or Uña de gato, is a medicinal plant that has been shown to have effective anti-inflammatory activities. We have previously shown that treatment of monocyte-like THP-1 cells with Uncaria tomentosa inhibits the production of the pro-inflammatory cytokine TNF-alpha while augmenting the production of IL-1beta. Since TNF-alpha and IL-1beta are usually regulated similarly and share a number of common promoter elements, including NF-kappaB and AP-1, the ability of Uncaria tomentosa to differentially regulate these inflammatory cytokines is of particular interest. To determine the mechanism of action of Uncaria tomentosa, we investigated the effects of specific inhibitors of NF-kappaB on cellular responses including transcription factor activation using TransAM assays, the expression of cytokines as measured by ELISA, and cell survival as measured by changes in cell number following treatment. Treatment with Uncaria tomentosa inhibited the LPS-dependent activation of specific NF-kappaB and AP-1 components. In addition, treatment with Uncaria tomentosa enhanced cell death when NF-kappaB was inhibited. The ability of Uncaria tomentosa to inhibit TNF-alpha production was diminished when NF-kappaB activation was prevented by drugs that mask NF-kappaB subunit nuclear localization signals, while IL-1beta expression was unchanged. These results demonstrate that Uncaria tomentosa is able to elicit a response via an NF-kappaB-dependent mechanism. Further studies to characterize the mechanism by which Uncaria tomentosa can affect this pathway could provide a means to develop anti-TNF-alpha therapies. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  6. The TNF-alpha transgenic mouse model of inflammatory arthritis.

    Science.gov (United States)

    Li, Ping; Schwarz, Edward M

    2003-08-01

    Rheumatoid arthritis is a chronic inflammatory disorder that affects multiple peripheral joints. It is the most common form of inflammatory arthritis and is characterized by synovial hyperplasia, immune cell infiltration, cartilage destruction, and bone erosion. To gain insight into the etiology of the disease, a variety of animal models have been established. Twelve years ago George Kollias' laboratory generated a transgenic (Tg) mouse that over-expresses human TNF-alpha, and develops an erosive polyarthritis with many characteristics observed in rheumatoid arthritis patients. The phenotype of this mouse model validated the theory that TNF-alpha is at the apex of the pro-inflammatory cascade in rheumatoid arthritis, and foreshadowed the remarkable success of anti-TNF-alpha therapy that has transformed the effective management of this disease. As such, the TNF-Tg mice are very useful tools for dissecting the molecular mechanisms of the pathogenic process and evaluating the efficacy of novel therapeutic strategies for rheumatoid arthritis. In this review we (1) provide a brief summary of TNF-alpha biology and the role of this dominant cytokine in rheumatoid arthritis, (2) describe the various TNF-Tg models and their phenotypes, and (3) give examples of how this model has been used experimentally.

  7. The potential role of suppressors of cytokine signaling in the attenuation of inflammatory reaction and alveolar bone loss associated with apical periodontitis.

    Science.gov (United States)

    Menezes, Renato; Garlet, Thiago Pompermaier; Trombone, Ana Paula Fávaro; Repeke, Carlos Eduardo; Letra, Ariadne; Granjeiro, José Mauro; Campanelli, Ana Paula; Garlet, Gustavo Pompermaier

    2008-12-01

    Inflammatory cytokines contribute to periapical tissue destruction. Their activity is potentially regulated by suppressors of cytokine signaling (SOCS), which downregulate signal transduction as part of an inhibitory feedback loop. We investigated the expression of the cytokines tumor necrosis factor alpha (TNF-alpha); interleukin (IL)-10 and RANKL; and SOCS-1, -2, and -3 by real-time polymerase chain reaction in 57 periapical granulomas and 38 healthy periapical tissues. Periapical granulomas exhibited significantly higher SOCS-1, -2, and -3, TNF-alpha, IL-10, and RANKL messenger RNA levels when compared with healthy controls. Significant positive correlations were found between SOCS1 and IL-10 and between SOCS3 and IL-10. Significant inverse correlations were observed between SOCS1 and TNF-alpha, SOCS1 and RANKL, and SOCS3 and TNF-alpha. Increased SOCS-1, -2, and -3 messenger RNA levels in periapical granulomas may be related to the downregulation of inflammatory cytokines in these lesions; therefore, SOCS molecules may play a role in the dynamics of periapical granulomas development.

  8. TNF-α and IFN-γ Together Up-Regulates Par-4 Expression and Induce Apoptosis in Human Neuroblastomas.

    Science.gov (United States)

    Shelke, Ganesh V; Jagtap, Jayashree C; Kim, Dae-Kyum; Shah, Reecha D; Das, Gowry; Shivayogi, Mruthyunjaya; Pujari, Radha; Shastry, Padma

    2017-12-26

    The objective of this study was to examine the combined effect of Interferon-gamma (IFN-γ) and Tumor Necrosis factor-alpha (TNF-α) on cytotoxicity and expression of prostate apoptosis response-4 (Par-4) and Par-4 interacting proteins B-cell lymphoma (Bcl-2), nuclear factor kappa-light-chain-enhancer of activated B cells/p65 subunit (NF-κB/p65), Ak mouse strain thymoma (Akt) in human neuroblastoma (NB) cells. Materials and methods included human neuroblastoma cell lines-SK-N-MC, SK-N-SH, and SH-SY5Y, which were treated with IFN-γ and TNF-α individually, or in combination, and were assessed for viability by tetrazolium (MTT) assay. Apoptosis was monitored by hypodiploid population (by flow cytometry), DNA fragmentation, Poly (ADP-ribose) polymerase (PARP) cleavage, and caspase-8 activity. Transcript level of Par-4 was measured by RT-PCR. Protein levels of Par-4 and suppressor of cytokine signaling 3 (SOCS-3) were assessed by immunoblotting. Cellular localization of Par-4 and p65 was examined by immunofluorescence. Unbiased transcript analysis for IFN-γ, TNF-α, and Par-4 were analyzed from three independent clinical datasets from neuroblastoma patients. In terms of results, SK-N-MC cells treated with a combination of, but not individually with, IFN-γ and TNF-α induced apoptosis characterized by hypodiploidy, DNA fragmentation, PARP cleavage, and increased caspase-8 activity. Apoptosis was associated with up-regulation of Par-4 mRNA and protein expression. Immunofluorescence studies revealed that Par-4 was localized exclusively in cytoplasm in SK-N-MC cells cultured for 24 h. but showed nuclear localization at 48 h. Treatment with IFN-γ and TNF-α together enhanced the intensity of nuclear Par-4. In gene expression, data from human neuroblastoma patients, levels of IFN-γ, and TNF-α have strong synergy with Par-4 expression and provide good survival advantage. The findings also demonstrated that apoptosis was associated with reduced level of pro

  9. TNF-α and IFN-γ Together Up-Regulates Par-4 Expression and Induce Apoptosis in Human Neuroblastomas

    Directory of Open Access Journals (Sweden)

    Ganesh V. Shelke

    2017-12-01

    Full Text Available The objective of this study was to examine the combined effect of Interferon-gamma (IFN-γ and Tumor Necrosis factor-alpha (TNF-α on cytotoxicity and expression of prostate apoptosis response-4 (Par-4 and Par-4 interacting proteins B-cell lymphoma (Bcl-2, nuclear factor kappa-light-chain-enhancer of activated B cells/p65 subunit (NF-κB/p65, Ak mouse strain thymoma (Akt in human neuroblastoma (NB cells. Materials and methods included human neuroblastoma cell lines-SK-N-MC, SK-N-SH, and SH-SY5Y, which were treated with IFN-γ and TNF-α individually, or in combination, and were assessed for viability by tetrazolium (MTT assay. Apoptosis was monitored by hypodiploid population (by flow cytometry, DNA fragmentation, Poly (ADP-ribose polymerase (PARP cleavage, and caspase-8 activity. Transcript level of Par-4 was measured by RT-PCR. Protein levels of Par-4 and suppressor of cytokine signaling 3 (SOCS-3 were assessed by immunoblotting. Cellular localization of Par-4 and p65 was examined by immunofluorescence. Unbiased transcript analysis for IFN-γ, TNF-α, and Par-4 were analyzed from three independent clinical datasets from neuroblastoma patients. In terms of results, SK-N-MC cells treated with a combination of, but not individually with, IFN-γ and TNF-α induced apoptosis characterized by hypodiploidy, DNA fragmentation, PARP cleavage, and increased caspase-8 activity. Apoptosis was associated with up-regulation of Par-4 mRNA and protein expression. Immunofluorescence studies revealed that Par-4 was localized exclusively in cytoplasm in SK-N-MC cells cultured for 24 h. but showed nuclear localization at 48 h. Treatment with IFN-γ and TNF-α together enhanced the intensity of nuclear Par-4. In gene expression, data from human neuroblastoma patients, levels of IFN-γ, and TNF-α have strong synergy with Par-4 expression and provide good survival advantage. The findings also demonstrated that apoptosis was associated with reduced level of pro

  10. TNF-α-induced NF-κB activation promotes myofibroblast differentiation of LR-MSCs and exacerbates bleomycin-induced pulmonary fibrosis.

    Science.gov (United States)

    Hou, Jiwei; Ma, Tan; Cao, Honghui; Chen, Yabing; Wang, Cong; Chen, Xiang; Xiang, Zou; Han, Xiaodong

    2018-03-01

    Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and irreversible lung disease of unknown cause. It has been reported that both lung resident mesenchymal stem cells (LR-MSCs) and tumor necrosis factor-α (TNF-α) play important roles in the development of pulmonary fibrosis. However, the underlying connections between LR-MSCs and TNF-α in the pathogenesis of pulmonary fibrosis are still elusive. In this study, we found that the pro-inflammatory cytokine TNF-α and the transcription factor nuclear factor kappa B (NF-κB) p65 subunit were both upregulated in bleomycin-induced fibrotic lung tissue. In addition, we discovered that TNF-α promotes myofibroblast differentiation of LR-MSCs through activating NF-κB signaling. Interestingly, we also found that TNF-α promotes the expression of β-catenin. Moreover, we demonstrated that suppression of the NF-κB signaling could attenuate myofibroblast differentiation of LR-MSCs and bleomycin-induced pulmonary fibrosis which were accompanied with decreased expression of β-catenin. Our data implicates that inhibition of the NF-κB signaling pathway may provide a therapeutic strategy for pulmonary fibrosis, a disease that warrants more effective treatment approaches. © 2017 Wiley Periodicals, Inc.

  11. Anti-TNF drives regulatory T cell expansion by paradoxically promoting membrane TNF–TNF-RII binding in rheumatoid arthritis

    Science.gov (United States)

    2016-01-01

    The interplay between inflammatory and regulatory pathways orchestrates an effective immune response that provides protection from pathogens while limiting injury to host tissue. Tumor necrosis factor (TNF) is a pivotal inflammatory cytokine, but there is conflicting evidence as to whether it boosts or inhibits regulatory T cells (T reg cells). In this study, we show that the therapeutic anti-TNF antibody adalimumab, but not the soluble TNF receptor etanercept, paradoxically promoted the interaction between monocytes and T reg cells isolated from patients with rheumatoid arthritis (RA). Adalimumab bound to monocyte membrane TNF from RA patients and unexpectedly enhanced its expression and its binding to TNF-RII expressed on T reg cells. As a consequence, adalimumab expanded functional Foxp3+ T reg cells equipped to suppress Th17 cells through an IL-2/STAT5-dependent mechanism. Our data not only highlight the beneficial effect of membrane TNF on T reg cell numbers during chronic inflammation, but in addition reveal how a therapeutic antibody that is thought to act by simply blocking its target can enhance the regulatory properties of this proinflammatory cytokine. PMID:27270893

  12. CD40L and TNF both activate the classical NF-κB pathway, which is not required for the CD40L induced alternative pathway in endothelial cells.

    Science.gov (United States)

    Seigner, J; Basilio, J; Resch, U; de Martin, R

    2018-01-01

    CD40L and TNF signal through engagement of their respective receptors, which are both members of the TNF receptor family. They use partially common signaling molecules leading, among others, to activation of the NF-κB pathway. However, whereas TNF activates the classical, CD40L has been reported to activate the alternative NF-κB pathway, leading to the anticipation that differences in the pattern of inflammatory gene expression would occur. Here, we have compared the gene expression repertoire of CD40L (CD154) and TNF stimulated HUVEC and report that unexpectedly, apart from a stronger response to TNF, no major qualitative differences could be observed. This applies for the period of up to 6 h, a time where the alternative pathway has already been activated. Analysis of the early events after receptor engagement revealed that both TNF and CD40L activate the classical NF-κB pathway, and confirm activation of the alternative by the latter. Furthermore, using genetic and pharmacological inhibition of the classical pathway we show that activation of the alternative occurs independently of the former. This reveals novel insights into NF-κB signaling by CD40L and TNF in endothelial cells. Copyright © 2017. Published by Elsevier Inc.

  13. Epstein-Barr virus large tegument protein BPLF1 contributes to innate immune evasion through interference with toll-like receptor signaling.

    Directory of Open Access Journals (Sweden)

    Michiel van Gent

    2014-02-01

    Full Text Available Viral infection triggers an early host response through activation of pattern recognition receptors, including Toll-like receptors (TLR. TLR signaling cascades induce production of type I interferons and proinflammatory cytokines involved in establishing an anti-viral state as well as in orchestrating ensuing adaptive immunity. To allow infection, replication, and persistence, (herpesviruses employ ingenious strategies to evade host immunity. The human gamma-herpesvirus Epstein-Barr virus (EBV is a large, enveloped DNA virus persistently carried by more than 90% of adults worldwide. It is the causative agent of infectious mononucleosis and is associated with several malignant tumors. EBV activates TLRs, including TLR2, TLR3, and TLR9. Interestingly, both the expression of and signaling by TLRs is attenuated during productive EBV infection. Ubiquitination plays an important role in regulating TLR signaling and is controlled by ubiquitin ligases and deubiquitinases (DUBs. The EBV genome encodes three proteins reported to exert in vitro deubiquitinase activity. Using active site-directed probes, we show that one of these putative DUBs, the conserved herpesvirus large tegument protein BPLF1, acts as a functional DUB in EBV-producing B cells. The BPLF1 enzyme is expressed during the late phase of lytic EBV infection and is incorporated into viral particles. The N-terminal part of the large BPLF1 protein contains the catalytic site for DUB activity and suppresses TLR-mediated activation of NF-κB at, or downstream of, the TRAF6 signaling intermediate. A catalytically inactive mutant of this EBV protein did not reduce NF-κB activation, indicating that DUB activity is essential for attenuating TLR signal transduction. Our combined results show that EBV employs deubiquitination of signaling intermediates in the TLR cascade as a mechanism to counteract innate anti-viral immunity of infected hosts.

  14. Illicium verum extract inhibits TNF-α- and IFN-γ-induced expression of chemokines and cytokines in human keratinocytes.

    Science.gov (United States)

    Sung, Yoon-Young; Kim, Young Sang; Kim, Ho Kyoung

    2012-10-31

    Illicium verum Hook. f. (star anise) has been used in traditional medicine for treatment of skin inflammation, rheumatism, asthma, and bronchitis. This study investigated the anti-inflammatory effects of Illicium verum extract (IVE) in the human keratinocyte HaCaT cell line. We investigated the effectiveness of IVE in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced human keratinocytes. To measure the effects of IVE on chemokine and pro-inflammatory cytokine expression in HaCaT cells, we used the following methods: cell viability assay, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, and luciferase reporter assay. IVE inhibited the expression of TNF-α/IFN-γ-induced mRNA and protein expression of thymus and activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22), interleukin (IL)-6, and IL-1β. Furthermore, IVE decreased TNF-α/IFN-γ-induced mRNA expression of intercellular adhesion molecule-1 (ICAM-1). IVE inhibited nuclear factor (NF)-κB translocation into the nucleus, as well as phosphorylation and degradation of IκBα. IVE inhibited TNF-α/IFN-γ-induced NF-κB and signal transducer and activator of transcription (STAT)1 activation in a dose-dependent manner. In addition, IVE significantly inhibited activation of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), and Akt. Furthermore, IVE contained 2.14% trans-anethole and possessed significant anti-inflammatory activities. IVE exerts anti-inflammatory effects by suppressing the expression of TNF-α/IFN-γ-induced chemokines, pro-inflammatory cytokines, and adhesion molecules via blockade of NF-κB, STAT1, MAPK, and Akt activation, suggesting that IVE may be a useful therapeutic candidate for inflammatory skin diseases, such as atopic dermatitis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Experimental Disc Herniation in the Rat Causes Downregulation of Serotonin Receptor 2c in a TNF-dependent Manner.

    Science.gov (United States)

    Jonsson, Daniel; Finskas, Oscar; Fujioka, Yuki; Ståhlberg, Anders; Olmarker, Kjell

    2015-06-01

    During recent decades, the knowledge of the pathophysiology of disc herniation and sciatica has drastically improved. What previously was considered a strict biomechanical process is now considered a more complex interaction between leaked nucleus pulposus and the tissue in the spinal canal. An inflammatory reaction, with tumor necrosis factor (TNF) playing an essential role, has been demonstrated. However, the exact mechanisms of the pathophysiology of disc herniation remain unknown. In this study we use an animal model to investigate (1) if and/or how experimental disc herniation affects gene expression in the early phase (24 hours postsurgery) in the dorsal root ganglion; and (2) if TNF inhibition can reduce any observed changes. A rat model of disc herniation was used. Twenty rats were evenly divided into four groups: naïve, sham, disc herniation, and disc herniation with TNF inhibition. The dorsal root ganglion of the affected nerve root was harvested 24 hours after surgery and analyzed with a TaqMan Low Density Array(®) quantitative polymerase chain reaction assay. Gene expression levels in sham were compared with disc herniation to assess question 1 and disc herniation to disc herniation with TNF inhibition to assess question 2. Experimental disc herniation caused a decrease in the expression of the serotonin receptor 2c gene (p = 0.022). TNF inhibition was found to reduce the observed decrease in expression of serotonin receptor 2c (p = 0.037). Our results suggest that a decrease in the expression of the serotonin receptor 2c gene may contribute to the pathophysiology of disc herniation. Further research on its involvement is warranted. This pilot study gives a brief insight into cellular changes that may contribute to the pathophysiology of disc herniation. This knowledge may contribute to the development of more and better treatment options for patients with disc herniation and sciatica.

  16. Cell lysis-free quantum dot multicolor cellular imaging-based mechanism study for TNF-α-induced insulin resistance.

    Science.gov (United States)

    Kim, Min Jung; Rangasamy, Sabarinathan; Shim, Yumi; Song, Joon Myong

    2015-01-27

    TNF-α is an inflammatory cytokine that plays an important role in insulin resistance observed in obesity and chronic inflammation. Many cellular components involved in insulin signaling cascade are known to be inhibited by TNF-α. Insulin receptor substrate (IRS)-1 is one of the major targets in TNF-α-induced insulin resistance. The serine phosphorylation of IRS-1 enables the inhibition of insulin signaling. Until now, many studies have been conducted to investigate the mechanism of TNF-α-induced insulin resistance based on Western blot. Intracellular protein kinase crosstalk is commonly encountered in inflammation-associated insulin resistance. The crosstalk among the signaling molecules obscures the precise role of kinases in insulin resistance. We have developed a cell lysis-free quantum dots (QDots) multicolor cellular imaging to identify the biochemical role of multiple kinases (p38, JNK, IKKβ, IRS1ser, IRS1tyr, GSK3β, and FOXO1) in inflammation-associated insulin resistance pathway with a single assay in one run. QDot-antibody conjugates were used as nanoprobes to simultaneously monitor the activation/deactivation of the above seven intracellular kinases in HepG2 cells. The effect of the test compounds on the suppression of TNF-α-induced insulin resistance was validated through kinase monitoring. Aspirin, indomethacin, cinnamic acid, and amygdalin were tested. Through the measurement of the glycogen level in HepG2 cell treated with TNF-α, it was found that aspirin and indomethacin increased glycogen levels by almost two-fold compared to amygdalin and cinnamic acid. The glucose production assay proved that cinnamic acid was much more efficient in suppressing glucose production, compared with MAP kinase inhibitors and non-steroidal anti-inflammatory drugs. QDot multicolor cellular imaging demonstrated that amygdalin and cinnamic acid selectively acted via the JNK1-dependent pathway to suppress the inflammation-induced insulin resistance and improve

  17. Immune signal transduction in leishmaniasis from natural to artificial systems: role of feedback loop insertion.

    Science.gov (United States)

    Mol, Milsee; Patole, Milind S; Singh, Shailza

    2014-01-01

    Modulated immune signal (CD14-TLR and TNF) in leishmaniasis can be linked to EGFR pathway involved in wound healing, through crosstalk points. This signaling network can be further linked to a synthetic gene circuit acting as a positive feedback loop to elicit a synchronized intercellular communication among the immune cells which may contribute to a better understanding of signaling dynamics in leishmaniasis. Network reconstruction with positive feedback loop, simulation (ODE 15s solver) and sensitivity analysis of CD14-TLR, TNF and EGFR was done in SimBiology (MATLAB 7.11.1). Cytoscape and adjacency matrix were used to calculate network topology. PCA was extracted by using sensitivity coefficient in MATLAB. Model reduction was done using time, flux and sensitivity score. Network has five crosstalk points: NIK, IκB-NFκB and MKK (4/7, 3/6, 1/2) which show high flux and sensitivity. PI3K in EGFR pathway shows high flux and sensitivity. PCA score was high for cytoplasmic ERK1/2, PI3K, Atk, STAT1/3 and nuclear JNK. Of the 125 parameters, 20% are crucial as deduced by model reduction. EGFR can be linked to CD14-TLR and TNF through the MAPK crosstalk points. These pathways may be controlled through Ras and Raf that lie upstream of signaling components ERK ½ (c) and JNK (n) that have a high PCA score via a synthetic gene circuit for activating cell-cell communication to elicit an inflammatory response. Also a disease resolving effect may be achieved through PI3K in the EGFR pathway. The reconstructed signaling network can be linked to a gene circuit with a positive feedback loop, for cell-cell communication resulting in synchronized response in the immune cell population, for disease resolving effect in leishmaniasis. © 2013 Elsevier B.V. All rights reserved.

  18. Serum levels of the bone turnover markers dickkopf-1, osteoprotegerin, and TNF-α in knee osteoarthritis patients.

    Science.gov (United States)

    Min, Sicong; Wang, Chao; Lu, Wanli; Xu, Zhihong; Shi, Dongquan; Chen, Dongyang; Teng, Huajian; Jiang, Qing

    2017-10-01

    Knee osteoarthritis (KOA) is a common degenerative joint disease causing pain, stiffness, reduced motion, swelling, crepitus, and disability. Several inflammatory markers and cartilage degradation products can be used as biomarkers in OA. The key factors of bone metabolism in normal joint bone, dickkopf-1 (DKK1) and osteoprotegerin (OPG), interact with Wnt signaling pathway, balancing between bone absorption and bone reconstruction. TNF-α is a key inducer of DKK-1, which belongs to the family of proteins involved in joint remodeling. The present study compared the serum levels of DKK1, TNF-α, and OPG in patients with KOA and healthy controls to analyze the interrelationship and the severity of joint destruction. One hundred forty-eight patients with KOA and 101 healthy controls were enrolled in this study. Anteroposterior knee radiographs determined the severity of the disease in the affected knee. The radiographic grading of KOA was performed by the Kellgren-Lawrence criteria. Serum levels of DKK-1, TNF-α, and OPG were estimated using the multiplex particle-based flow cytometry. Higher serum levels of OPG and TNF-α were observed in KOA than the controls; KOA patients showed a lower serum level of DKK-1, whereas the serum levels of DKK1 correlated with the progression of KOA. The serum levels of TNF-α, OPG, and DKK-1 correlated with incident KOA. In the ROC curve analysis, DKK1 levels showed 78.6% sensitivity and 40% specificity, TNF-α levels showed 74.1% sensitivity and 76.0% specificity, and OPG showed 88.1% sensitivity and 81% specificity in predicting severe KOA. In the univariate and multivariate analyses, TNF-α and OPG emerged as independent predictors of severe KOA. This study, for the first time, combined TNF-α, DKK1, and OPG as valuable biological markers in predicting the severity of KOA radiographically in the clinic. This study also supported the inflammation-induced DKK1 and OPG in OA pathogenesis.

  19. Soluble forms of tumor necrosis factor receptors (TNF-Rs). The cDNA for the type I TNF-R, cloned using amino acid sequence data of its soluble form, encodes both the cell surface and a soluble form of the receptor

    DEFF Research Database (Denmark)

    Nophar, Y; Kemper, O; Brakebusch, C

    1990-01-01

    the extracellular domain of the type I TNF-R matches the COOH-terminal sequence of TBPI. Amino acid sequences in the extracellular domain also fully match other sequences found in TBPI. On the other hand, amino acid sequences in the soluble form of the type II TNF-R (TBPII), while indicating a marked homology...... found to have effects characteristic of TNF, including stimulating phosphorylation of specific cellular proteins. Oligonucleotide probes designed on the basis of the NH2-terminal amino acid sequence of TBPI were used to clone the cDNA for the structurally related cell surface type 1 TNF-R. It is notable...... that although this receptor can signal the phosphorylation of cellular proteins, it appears from its amino acid sequence to be devoid of intrinsic protein kinase activity. The extracellular domain of the receptor is composed of four internal cysteine-rich repeats, homologous to structures repeated four times...

  20. PUMA amplifies necroptosis signaling by activating cytosolic DNA sensors.

    Science.gov (United States)

    Chen, Dongshi; Tong, Jingshan; Yang, Liheng; Wei, Liang; Stolz, Donna B; Yu, Jian; Zhang, Jianke; Zhang, Lin

    2018-04-10

    Necroptosis, a form of regulated necrotic cell death, is governed by RIP1/RIP3-mediated activation of MLKL. However, the signaling process leading to necroptotic death remains to be elucidated. In this study, we found that PUMA , a proapoptotic BH3-only Bcl-2 family member, is transcriptionally activated in an RIP3/MLKL-dependent manner following induction of necroptosis. The induction of PUMA, which is mediated by autocrine TNF-α and enhanced NF-κB activity, contributes to necroptotic death in RIP3-expressing cells with caspases inhibited. On induction, PUMA promotes the cytosolic release of mitochondrial DNA and activation of the DNA sensors DAI/Zbp1 and STING, leading to enhanced RIP3 and MLKL phosphorylation in a positive feedback loop. Furthermore, deletion of PUMA partially rescues necroptosis-mediated developmental defects in FADD -deficient embryos. Collectively, our results reveal a signal amplification mechanism mediated by PUMA and cytosolic DNA sensors that is involved in TNF-driven necroptotic death in vitro and in vivo. Copyright © 2018 the Author(s). Published by PNAS.

  1. Molecular probing of TNF: From identification of therapeutic target to guidance of therapy in inflammatory diseases.

    Science.gov (United States)

    Chu, Cong-Qiu

    2018-01-01

    Therapy by blocking tumor necrosis factor (TNF) activity is highly efficacious and profoundly changed the paradigm of several inflammatory diseases. However, a significant proportion of patients with inflammatory diseases do not respond to TNF inhibitors (TNFi). Prediction of therapeutic response is required for TNFi therapy. Isotope labeled anti-TNF antibodies or TNF receptor have been investigated to localize TNF production at inflammatory tissue in animal models and in patients with inflammatory diseases. The in vivo detection of TNF has been associated with treatment response. Recently, fluorophore labeled anti-TNF antibody in combination with confocal laser endomicroscopy in patients with Crohn's disease yielded more accurate and quantitative in vivo detection of TNF in the diseased mucosa. More importantly, this method demonstrated high therapeutic predication value. Fluorophore labeled TNF binding aptamers in combination with modern imaging technology offers additional tools for in vivo TNF probing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. TNF-alpha −308G/A and −238G/A polymorphisms and its protein network associated with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Kaiser Jamil

    2017-09-01

    Full Text Available Several reports document the role of tumor necrosis factor alpha (TNF-α and lipid metabolism in the context of acute inflammation as a causative factor in obesity-associated insulin resistance and as one of the causative parameter of type 2 diabetes mellitus (T2DM. Our aim was to investigate the association between −308G/A and −238G/A polymorphisms located in the promoter region of the TNF-α gene in T2DM in the Indian population with bioinformatics analysis of TNF-α protein networking with an aim to find new target sites for the treatment of T2DM. Demographics of 100 diabetes patients and 100 healthy volunteers were collected in a structured proforma and 3 ml blood samples were obtained from the study group, after approval of Institutional Ethics Committee of the hospital (IEC. The information on clinical parameters was obtained from medical records. Genomic DNA was extracted; PCR–RFLP was performed using TNF-α primers specific to detect the presence of SNPs. Various bioinformatics tools such as STRING software were used to determine its network with other associated genes. The PCR–RFLP studies showed that among the −238G/A types the GG genotype was 87%, GA genotype was 12% and AA genotype was 1%. Almost a similar pattern of results was obtained with TNF-α −308G/A polymorphism. The results obtained were evaluated statistically to determine the significance. By constructing TNF-α protein interaction network we could analyze ontology and hubness of the network to identify the networking of this gene which may influence the functioning of other genes in promoting T2DM. We could identify new targets in T2DM which may function in association with TNF-α. Through hub analysis of TNF-α protein network we have identified three novel proteins RIPK1, BIRC2 and BIRC3 which may contribute to TNF-mediated T2DM pathogenesis. In conclusion, our study indicated that some of the genotypes of TNF-α −308G/A, −238G/A were not significantly

  3. Apoptotic cells can induce non-autonomous apoptosis through the TNF pathway

    Science.gov (United States)

    Pérez-Garijo, Ainhoa; Fuchs, Yaron; Steller, Hermann

    2013-01-01

    Apoptotic cells can produce signals to instruct cells in their local environment, including ones that stimulate engulfment and proliferation. We identified a novel mode of communication by which apoptotic cells induce additional apoptosis in the same tissue. Strong induction of apoptosis in one compartment of the Drosophila wing disc causes apoptosis of cells in the other compartment, indicating that dying cells can release long-range death factors. We identified Eiger, the Drosophila tumor necrosis factor (TNF) homolog, as the signal responsible for apoptosis-induced apoptosis (AiA). Eiger is produced in apoptotic cells and, through activation of the c-Jun N-terminal kinase (JNK) pathway, is able to propagate the initial apoptotic stimulus. We also show that during coordinated cell death of hair follicle cells in mice, TNF-α is expressed in apoptotic cells and is required for normal cell death. AiA provides a mechanism to explain cohort behavior of dying cells that is seen both in normal development and under pathological conditions. DOI: http://dx.doi.org/10.7554/eLife.01004.001 PMID:24066226

  4. Transcriptome analysis of ankylosing spondylitis patients before and after TNF-α inhibitor therapy reveals the pathways affected.

    Science.gov (United States)

    Wang, X B; Ellis, J J; Pennisi, D J; Song, X; Batra, J; Hollis, K; Bradbury, L A; Li, Z; Kenna, T J; Brown, M A

    2017-09-01

    Tumor necrosis factor-α (TNF-α) inhibitors are highly effective in suppressing inflammation in ankylosing spondylitis (AS) patients, and operate by suppression of TFN-α and downstream immunological pathways. To determine the mechanisms of action of TNF-α inhibitors in AS patients, we used transcriptomic and bioinformatic approaches on peripheral blood mononuclear cells from AS patients pre and post treatment. We found 656 differentially expressed genes, including the genome-wide significant AS-associated genes, IL6R, NOTCH1, IL10, CXCR2 and TNFRSF1A. A distinctive gene expression profile was found between male and female patients, mainly because of sex chromosome-linked genes and interleukin 17 receptor C, potentially accounting for the differences in clinical manifestation and treatment response between the genders. In addition to immune and inflammation regulatory pathways, like intestinal immune network for IgA production, cytokine-cytokine receptor interaction, Ras signaling pathway, allograft rejection and hematopoietic cell lineage, KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analyses revealed that infection-associated pathways (influenza A and toxoplasmosis) and metabolism-associated pathways were involved in response to TNF-α inhibitor treatment, providing insight into the mechanism of TNF-α inhibitors.

  5. A role for the non-receptor tyrosine kinase ACK1 in TNF-alpha-mediated apoptosis and proliferation in human intestinal epithelial caco-2 cells.

    Science.gov (United States)

    Zhao, Xinmei; Lv, Chaolan; Chen, Shengbo; Zhi, Fachao

    2017-09-16

    The roles of tumor necrosis factor alpha (TNF-alpha) and its mediators in cellular processes related to intestinal diseases remain elusive. In this study, we aimed to determine the biological role of activated Cdc42-associated kinase 1 (ACK1) in TNF-alpha-mediated apoptosis and proliferation in Caco-2 cells. ACK1 expression was knocked down using ACK1-specific siRNAs, and ACK1 activity was disrupted using a small molecule ACK1 inhibitor. The Terminal deoxynucleotidyl transferase biotin-dUTP Nick End Labeling (TUNEL) and the BrdU incorporation assays were used to measure apoptosis and cell proliferation, respectively. ACK1-specific siRNA and the pharmacological ACK1 inhibitor significantly abrogated the TNF-alpha-mediated anti-apoptotic effects and proliferation of Caco-2 cells. Interestingly, TNF-alpha activated ACK1 at tyrosine 284 (Tyr284), and the ErbB family of proteins was implicated in ACK1 activation in Caco-2 cells. ACK1-Tyr284 was required for protein kinase B (AKT) activation, and ACK1 signaling was mediated through recruiting and phosphorylating the down-stream adaptor protein AKT, which likely promoted cell proliferation in response to TNF-alpha. Moreover, ACK1 activated AKT and Src enhanced nuclear factor-кB (NF-кB) activity, suggesting a correlation between NF-кB signaling and TNF-alpha-mediated apoptosis in Caco-2 cells. Our results demonstrate that ACK1 plays an important role in modulating TNF-alpha-induced aberrant cell proliferation and apoptosis, mediated in part by ACK1 activation. ACK1 and its down-stream effectors may hold promise as therapeutic targets in the prevention and treatment of gastrointestinal cancers, in particular, those induced by chronic intestinal inflammation. © 2017 The Authors. Cell Biology International Published by John Wiley & Sons Ltd on behalf of International Federation of Cell Biology.

  6. TNF-alpha, leptin, and lymphocyte function in human aging

    DEFF Research Database (Denmark)

    Bruunsgaard, H.; Pedersen, Agnes Nadelmann; Schroll, M.

    2000-01-01

    Aging is associated with increased inflammatory activity and concomitant decreased T cell mediated immune responses. Leptin may provide a link between inflammation and T cell function in aging. The aim of the study was to investigate if plasma levels of tumor necrosis factor (TNF)-alpha were...... associated with leptin, circulating interleukin-2 receptors (sIL-2R), and phytohaemagglutinin (PHA) induced IL-2 production in whole blood in elderly humans. Circulating levels of TNF-alpha and sIL-2R were higher in elderly humans (N=42) compared to a young control group (N=37) whereas...... there was no difference with regard to IL-2 production. Furthermore, there were no age-related differences in serum levels of leptin, However, women had higher levels than men. In the elderly people, serum levels of leptin were correlated with TNF-alpha in univariate regression analysis and in a multiple linear...

  7. Activation of Extracellular Signal-Regulated Kinases (ERK 1/2) in the Locus Coeruleus Contributes to Pain-Related Anxiety in Arthritic Male Rats.

    Science.gov (United States)

    Borges, Gisela; Miguelez, Cristina; Neto, Fani; Mico, Juan Antonio; Ugedo, Luisa; Berrocoso, Esther

    2017-06-01

    There is increasing evidence suggesting that the Locus Coeruleus plays a role in pain-related anxiety. Indeed, we previously found that prolonged arthritis produces anxiety-like behavior in rats, along with enhanced expression of phosphorylated extracellular signal-regulated kinase 1/2 (a marker of plasticity) in the Locus Coeruleus. However, it is unknown how this effect correlates with the electrophysiological activity of Locus Coeruleus neurons or pain-related anxiety. Using the complete Freund's adjuvant model of monoarthritis in male Sprague-Dawley rats, we studied the behavioral attributes of pain and anxiety as well as Locus Coeruleus electrophysiology in vivo 1 (MA1W) and 4 weeks (MA4W) after disease induction. The manifestation of anxiety in MA4W was accompanied by dampened tonic Locus Coeruleus activity, which was coupled to an exacerbated evoked Locus Coeruleus response to noxious stimulation of the inflamed and healthy paw. When a mitogen-activating extracellular kinase inhibitor was administered to the contralateral Locus Coeruleus of MA4W, the phosphorylated extracellular signal-regulated kinase 1/2 levels in the Locus Coeruleus were restored and the exaggerated evoked response was blocked, reversing the anxiogenic-like behavior while pain hypersensitivity remained unaltered. As phosphorylated extracellular signal-regulated kinase 1/2 blockade in the Locus Coeruleus relieved anxiety and counteracted altered LC function, we propose that phosphorylated extracellular signal-regulated kinase 1/2 activation in the Locus Coeruleus plays a crucial role in pain-related anxiety. © The Author 2017. Published by Oxford University Press on behalf of CINP.

  8. Decreased SAP Expression in T Cells from Patients with Systemic Lupus Erythematosus Contributes to Early Signaling Abnormalities and Reduced IL-2 Production.

    Science.gov (United States)

    Karampetsou, Maria P; Comte, Denis; Kis-Toth, Katalin; Terhorst, Cox; Kyttaris, Vasileios C; Tsokos, George C

    2016-06-15

    T cells from patients with systemic lupus erythematosus (SLE) display a number of abnormalities, including increased early signaling events following engagement of the TCR. Signaling lymphocytic activation molecule family cell surface receptors and the X-chromosome-defined signaling lymphocytic activation molecule-associated protein (SAP) adaptor are important in the development of several immunocyte lineages and modulating the immune response. We present evidence that SAP protein levels are decreased in T cells and in their main subsets isolated from 32 women and three men with SLE, independent of disease activity. In SLE T cells, SAP protein is also subject to increased degradation by caspase-3. Forced expression of SAP in SLE T cells normalized IL-2 production, calcium (Ca(2+)) responses, and tyrosine phosphorylation of a number of proteins. Exposure of normal T cells to SLE serum IgG, known to contain anti-CD3/TCR Abs, resulted in SAP downregulation. We conclude that SLE T cells display reduced levels of the adaptor protein SAP, probably as a result of continuous T cell activation and degradation by caspase-3. Restoration of SAP levels in SLE T cells corrects the overexcitable lupus T cell phenotype. Copyright © 2016 by The American Association of Immunologists, Inc.

  9. Quinacrine Inhibits ICAM-1 Transcription by Blocking DNA Binding of the NF-κB Subunit p65 and Sensitizes Human Lung Adenocarcinoma A549 Cells to TNF-α and the Fas Ligand.

    Science.gov (United States)

    Harada, Misuzu; Morimoto, Kyoko; Kondo, Tetsuya; Hiramatsu, Reiko; Okina, Yuji; Muko, Ryo; Matsuda, Iyo; Kataoka, Takao

    2017-12-02

    Quinacrine has been used for therapeutic drugs in some clinical settings. In the present study, we demonstrated that quinacrine decreased the expression of intercellular adhesion molecule-1 (ICAM-1) induced by tumor necrosis factor (TNF)-α and interleukin-1 (IL-1) α in human lung adenocarcinoma A549 cells. Quinacrine inhibited ICAM-1 mRNA expression and nuclear factor κB (NF-κB)-responsive luciferase reporter activity following a treatment with TNF-α and IL-1α. In the NF-κB signaling pathway, quinacrine did not markedly affect the TNF-α-induced degradation of the inhibitor of NF-κB or the TNF-α-induced phosphorylation of the NF-κB subunit, p65, at Ser-536 and its subsequent translocation to the nucleus. In contrast, a chromatin immunoprecipitation assay showed that quinacrine prevented the binding of p65 to the ICAM-1 promoter following TNF-α stimulation. Moreover, TNF-α and the Fas ligand effectively reduced the viability of A549 cells in the presence of quinacrine only. Quinacrine down-regulated the constitutive and TNF-α-induced expression of c-FLIP and Mcl-1 in A549 cells. These results revealed that quinacrine inhibits ICAM-1 transcription by blocking the DNA binding of p65 and sensitizes A549 cells to TNF-α and the Fas ligand.

  10. Schizophrenia - A disturbance of signal interaction between the entorhinal cortex and the dentate gyrus? The contribution of experimental dibenamine psychosis to the pathogenesis of schizophrenia: A hypothesis.

    Science.gov (United States)

    Arnold, O H

    1999-01-01

    In addition to the existence of complex memory (similar to the implicit nondeclarative memory of Squire), the existence of a phylogenetically old apparatus of a memory of situations (SMA) is supposed, which is to some extent comparable with the declarative memory of Squire. During actual sensory information the SMA generates a general frame and forms a general 'mark', indicating whether a given information has its origin inside or outside the body, and whether it is new or known. The procedure of this marking process can be explained as the time-depending arrest of a copy of the actual original information-transporting signal 'shower'; this copy must last until the feedback from thalamocortical centers indicates the termination of the processing of the original signal showers. The arrest of the shower copies is the performance of neuronal networks of the entorhinal cortex (EC) and the gyrus dentatus (GD). The psychopathological and biochemical analyses of experimental dibenamine psychosis show a different effect of dibenamine on the noradrenaline (NA) receptors of the EC and GD, respectively: these effects are responsible for the repeated perception cycles of a single situation. N,N-Dibencylamine blocks the postsynaptic alpha(1)-receptors of the EC without influencing the beta-receptors of the GD. Thus the interaction between EC and GD is changed: instead of new scenes, perceptions that have just been experienced get repeated presence and the quality of familiarity. The prolonged arrest of shower copies simultaneously blocks the entrance of new signal showers from the EC to the GD. No information-transporting signal showers can come in as long as the arrest lasts. In case of a disturbance in NA-dependent actions within the EC and the GD, the duration of arrest of information-transporting signal showers is shortened. Thus the formal frame of experience receives the quality of novelty instead of familiarity, and in addition the qualities of uncertainty, vagueness

  11. Cathepsin-D And Tnf-α in Bladder Cancer

    Directory of Open Access Journals (Sweden)

    T. Salman

    1996-01-01

    Full Text Available In a study of 34 normal healthy controls, 35 patients with urinary tract bilharziasis and 93 bladder cancer patients (62 of them are operable cases and 31 are non-operable ones, serum tumor necrosis factor alpha (TNF-α and cytosolic Cathepsin-D were estimated. Though both potential markers were elevated in bladder cancer patients, neither Cathepsin-D nor TNF-α showed associations of prognostic value since there were no positive correlations with tumor stages, grades or association of tumors with bilharzia ova or lymph node involvement.

  12. The Immune Signaling Adaptor LAT Contributes to the Neuroanatomical Phenotype of 16p11.2 BP2-BP3 CNVs

    NARCIS (Netherlands)

    Loviglio, Maria Nicla; Arbogast, Thomas; Jønch, Aia Elise; Collins, Stephan C.; Popadin, Konstantin; Bonnet, Camille S.; Giannuzzi, Giuliana; Maillard, Anne M.; Jacquemont, Sébastien; Loviglio, Maria Nicla; Jønch, Aia Elise; Popadin, Konstantin; Giannuzzi, Giuliana; Maillard, Anne M.; Fagerberg, Christina; Andersen, Charlotte Brasch; Doco-Fenzy, Martine; Delrue, Marie-Ange; Faivre, Laurence; Arveiler, Benoit; Geneviève, David; Schneider, Anouck; Gerard, Marion; Andrieux, Joris; El Chehadeh, Salima; Schaefer, Elise; Depienne, Christel; Van Haelst, Mieke; Brilstra, Eva H.; Van Binsbergen, Ellen; van Harssel, Jeske; van der Veken, Lars T.; Gusella, James F; Shen, Yiping; Mitchell, Elyse; Kini, Usha; Hawkes, Lara; Campbell, Carolyn; Butschi, Florence Niel; Addor, Marie Claude; Beckmann, Jacques S.; Jacquemont, Sébastien; Reymond, Alexandre; Yalcin, Binnaz; Katsanis, Nicholas; Golzio, Christelle; Reymond, Alexandre

    2017-01-01

    Copy-number changes in 16p11.2 contribute significantly to neuropsychiatric traits. Besides the 600 kb BP4-BP5 CNV found in 0.5%–1% of individuals with autism spectrum disorders and schizophrenia and whose rearrangement causes reciprocal defects in head size and body weight, a second distal 220 kb

  13. Importance of TNF-alpha in the course of acute infection with Trypanosoma cruzi: influence of its inhibition by pentoxifylline treatment

    Directory of Open Access Journals (Sweden)

    Sonia G Andrade

    2008-02-01

    Full Text Available Infection of C3H/He mice with the Peruvian strain of Trypanosoma cruzi (Biodeme type I, Z2b, a macrophagotropic strain, determined severe parasitism of macrophages, necrosis of the spleen, and high host mortality. In the present study, pentoxifylline (PTX, an inhibitor of TNF-alpha was investigated on its action upon splenic necrosis, parasitemia and host survival. Immunohistochemical data suggested the importance of this cytokine in parasite destruction and decreasing of parasitemia, although paradoxically contributing to the high mortality of infected mice. Necrotic lesions involving several organs, specially the heart, in acute Chagas disease, are important aggravating factors, increasing cardiac morbidity. Advantage of inhibiting TNF-alpha action was herein investigated. Infected mice were divided into two groups: untreated (n = 24, and PTX treated mice (n = 25. PTX was administered in two daily doses of 30 mg/kg/bw, by intraperitoneal route. Normal controls either treated with PTX or saline were also included. Histopathology of the spleen and in situ immunolabeling of TNF-alpha, using anti-TNF-alpha monoclonal antibody, were performed. Necrotic areas were evaluated by morphometry. Mice treated with PTX showed a significant decrease of necrotic areas and diminution of TNF-alpha expression in spleen tissue, suggesting that PTX treatment could control TNF-alpha effects, and thus be used as an adjuvant in the treatment of acute Chagas' disease.

  14. Glatiramer acetate (GA) prevents TNF-α-induced monocyte adhesion to primary endothelial cells through interfering with the NF-κB pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Guoqian; Zhang, Xueyan; Su, Zhendong; Li, Xueqi, E-mail: xueqili075@yeah.net

    2015-01-30

    Highlights: • GA inhibited TNF-α-induced binding of monocytes to endothelial cells. • GA inhibited the induction of adhesion molecules MCP-1, VCAM-1 and E-selectin. • GA inhibits NF-κB p65 nuclear translocation and transcriptional activity. • GA inhibits TNF-α-induced IκBα degradation. - Abstract: Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) is considered to be the major one contributing to the process of development of endothelial dysfunction. Exposure to TNF-α induces the expression of a number of proinflammatory chemokines, such as monocyte chemotactic protein-1 (MCP-1), and adhesion molecules, including vascular adhesion molecule-1 (VCAM-1) and E-selectin, which mediate the interaction of invading monocytes with vascular endothelial cells. Glatiramer acetate (GA) is a licensed clinical drug for treating patients suffering from multiple sclerosis (MS). The effects of GA in vascular disease have not shown before. In this study, we found that GA significantly inhibited TNF-α-induced binding of monocytes to endothelial cells. Mechanistically, we found that GA ameliorated the upregulation of MCP-1, VCAM-1, and E-selectin induced by TNF-α. Notably, this process is mediated by inhibiting the nuclear translocation and activation of NF-κB. Our results also indicate that GA pretreatment attenuates the up-regulation of COX-2 and iNOS. These data suggest that GA might have a potential benefit in therapeutic endothelial dysfunction related diseases.

  15. Electrical Excitation of the Pulmonary Venous Musculature May Contribute to the Formation of the Last Component of the High Frequency Signal of the P Wave

    Directory of Open Access Journals (Sweden)

    Junko Abe, MD

    2005-01-01

    Full Text Available Pulmonary veins (PVs have been shown to play an important role in the induction and perpetuation of focal AF. Fifty-one patients with AF, and 24 patients without AF as control subjects, were enrolled in this study. Signal-averaged P-wave recording was performed, and the filtered P wave duration (FPD, the root-mean-square voltage for the last 20, 30 and 40 ms (RMS20, 30, and 40, respectively were compared. In 7 patients with AF, these parameters were compared before and after the catheter ablation. The FPD was significantly longer and the RMS20 was smaller in the patients with AF than those without AF. Because RMS30 was widely distributed between 2 and 10 µV, the AF group was sub-divided into two groups; Group 1 was comprised of the patients with an RMS30 ≧5.0 µV, and group 2, <5.0 µV. In group 1, short-coupled PACs were more frequently documented on Holter monitoring, and exercise testing more readily induced AF. After successful electrical disconnection between the LA and PVs, each micropotential parameter was significantly attenuated. These results indicate that the high frequency signal amplitude of the last component of the P wave is relatively high in patients with AF triggered by focal repetitive excitations most likely originating from the PVs. That is, attenuation by the LA-PV electrical isolation, and thus the high frequency P signals of the last component, may contain the electrical excitation of the PV musculature.

  16. Phosphoinositide signaling.

    Science.gov (United States)

    Boss, Wendy F; Im, Yang Ju

    2012-01-01

    "All things flow and change…even in the stillest matter there is unseen flux and movement." Attributed to Heraclitus (530-470 BC), from The Story of Philosophy by Will Durant. Heraclitus, a Greek philosopher, was thinking on a much larger scale than molecular signaling; however, his visionary comments are an important reminder for those studying signaling today. Even in unstimulated cells, signaling pathways are in constant metabolic flux and provide basal signals that travel throughout the organism. In addition, negatively charged phospholipids, such as the polyphosphorylated inositol phospholipids, provide a circuit board of on/off switches for attracting or repelling proteins that define the membranes of the cell. This template of charged phospholipids is sensitive to discrete changes and metabolic fluxes-e.g., in pH and cations-which contribute to the oscillating signals in the cell. The inherent complexities of a constantly fluctuating system make understanding how plants integrate and process signals challenging. In this review we discuss one aspect of lipid signaling: the inositol family of negatively charged phospholipids and their functions as molecular sensors and regulators of metabolic flux in plants.

  17. Does the downregulation of the FGF23 signaling pathway in hyperplastic parathyroid glands contribute to refractory secondary hyperparathyroidism in CKD patients?

    Science.gov (United States)

    Lafage-Proust, Marie-Hélène

    2010-03-01

    Compared to normal tissue, hyperplastic parathyroid glands of patients with chronic kidney disease on dialysis express lower levels of FGFR1 and Klotho proteins. Similar findings are reported in uremic rats with advanced chronic kidney disease. Moreover, in these animals, FGF23 administration fails to reduce PTH serum levels in vivo and to transmit downstream signals in parathyroid cells ex vivo. These findings may explain, at least partly, the concomitant elevation of both FGF23 and PTH serum levels in chronic kidney disease secondary hyperparathyroidism.

  18. [PI 3 K/Akt signaling pathway contributed to the protective effect of acupuncture intervention on epileptic seizure-induced injury of hippocampal pyramidal cells in epilepsy rats].

    Science.gov (United States)

    Yang, Fan; Ang, Wen-Ping; Shen, De-Kai; Liu, Xiang-Guo; Yang, Yong-Qing; Ma, Yun

    2013-02-01

    To observe the protective effect of acupuncture stimulation on pyramidal cells in hippocampal CA 1 and CA 3 regions and to analyze the involvement of phosphatidy linositol-3-kinase (PI 3 K)/protein kinase B(PKB or Akt) signaling pathway in the acupuncture effect in epilepsy rats. A total of 120 SD rats were randomly divided into normal control group, model group, LY 294002 (a specific antagonist for PI 3 K/Akt signaling) group, acupuncture+ LY 294002 group and acupuncture group (n = 24 in each group, 12 for H. E. staining, and 12 for electron microscope observation). Epilepsy model was established by intraperitoneal injection of pentylenetetrazol (PTZ, 5 microL). Manual acupuncture stimulation was applied to "Baihui" (GV 20) and "Dazhui" (GV 14) once daily for 5 days. Dimethyl Sulfoxide (DMSO, 5 microL, a control solvent) was given to rats of the normal, model and acupuncture groups, and LY294002 (5 microL, dissolved in DMSO) given to rats of the LY 294002 and acupuncture+ LY 294002 groups by lateral ventricular injection. Four hours and 24 h after modeling, the hippocampus tissues were sampled for observing pathological changes of CA 1 and CA 3 regions after H. E. staining under light microscope and for checkin ultrastructural changes of the pyramidal cells under transmission electron microscope. In comparison with the normal control group, the numbers of pyramidal cells of hippocampal CA 3 region in the model group were decreased significantly 4 h and 24 h after epileptic seizure (P acupuncture group were increased considerably in the number at both 4 h and 24 h after seizure (P acupuncture+ LY 294002 and model groups in the numbers of pyramidal cells at 4 h and 24 h after seizure (P > 0.05). Findings of the light microscope and electron microscope showed that the injury severity of pyramidal cells of hippocampal CA 1 and CA 3 regions was moderate 4 h after epileptic seizure and even worse 24 h after seizure in the model group, LY 294002 group and acupuncture+ LY

  19. Reactive oxygen species via redox signaling to PI3K/AKT pathway contribute to the malignant growth of 4-hydroxy estradiol-transformed mammary epithelial cells.

    Directory of Open Access Journals (Sweden)

    Victor O Okoh

    Full Text Available The purpose of this study was to investigate the effects of 17-β-estradiol (E2-induced reactive oxygen species (ROS on the induction of mammary tumorigenesis. We found that ROS-induced by repeated exposures to 4-hydroxy-estradiol (4-OH-E2, a predominant catechol metabolite of E2, caused transformation of normal human mammary epithelial MCF-10A cells with malignant growth in nude mice. This was evident from inhibition of estrogen-induced breast tumor formation in the xenograft model by both overexpression of catalase as well as by co-treatment with Ebselen. To understand how 4-OH-E2 induces this malignant phenotype through ROS, we investigated the effects of 4-OH-E2 on redox-sensitive signal transduction pathways. During the malignant transformation process we observed that 4-OH-E2 treatment increased AKT phosphorylation through PI3K activation. The PI3K-mediated phosphorylation of AKT in 4-OH-E2-treated cells was inhibited by ROS modifiers as well as by silencing of AKT expression. RNA interference of AKT markedly inhibited 4-OH-E2-induced in vitro tumor formation. The expression of cell cycle genes, cdc2, PRC1 and PCNA and one of transcription factors that control the expression of these genes - nuclear respiratory factor-1 (NRF-1 was significantly up-regulated during the 4-OH-E2-mediated malignant transformation process. The increased expression of these genes was inhibited by ROS modifiers as well as by silencing of AKT expression. These results indicate that 4-OH-E2-induced cell transformation may be mediated, in part, through redox-sensitive AKT signal transduction pathways by up-regulating the expression of cell cycle genes cdc2, PRC1 and PCNA, and the transcription factor - NRF-1. In summary, our study has demonstrated that: (i 4-OH-E2 is one of the main estrogen metabolites that induce mammary tumorigenesis and (ii ROS-mediated signaling leading to the activation of PI3K/AKT pathway plays an important role in the generation of 4-OH-E2

  20. Genetic ablation of soluble TNF does not affect lesion size and functional recovery after moderate spinal cord injury in mice

    DEFF Research Database (Denmark)

    Ellman, Ditte Gry; Degn, Matilda; Lund, Minna C.

    2016-01-01

    Traumatic spinal cord injury (SCI) is followed by an instant increase in expression of the microglial-derived proinflammatory cytokine tumor necrosis factor (TNF) within the lesioned cord. TNF exists both as membrane-anchored TNF (mTNF) and as cleaved soluble TNF (solTNF). We previously demonstra......, and MHCII), lesion size, and functional outcome after moderate SCI were comparable between genotypes. Collectively, our data demonstrate that genetic ablation of solTNF does not significantly modulate postlesion outcome after SCI....

  1. Differential role of TNF-alpha and IFN-gamma in the brain of rats with chronic relapsing autoimmune encephalomyelitis.

    Science.gov (United States)

    Tanuma, N; Shin, T; Kogure, K; Matsumoto, Y

    1999-04-01

    To elucidate the mechanisms of relapses of the clinical signs in experimental autoimmune encephalomyelitis (EAE), the cytokine profile of chronic relapsing EAE (CR-EAE) in rats was determined by competitive polymerase chain reaction (PCR). By immunization with guinea pig spinal cord homogenate and treatment with low-dose cyclosporin A (CsA), rats developed two attacks of EAE with remission in between. Cytokine analysis revealed that the level of TNF-alpha mRNA increased at the first and second attacks with transient disappearance at the remission phase. In contrast, the level of IFN-gamma mRNA was suppressed at the first attack by CsA and peaked at the second attack. Intraventricular administration of IFN-gamma prior to onset of disease signs induced more relapses, or a severe lethal form. In addition, the intraventricular injection of TNF-alpha caused the persistence of the clinical signs. These findings suggest that TNF-alpha contributes to the first and second attacks of CR-EAE, while IFN-gamma is not required for the first attack but is closely related to the relapse of the disease. With regard to anti-inflammatory cytokines, the levels of both TGF-beta1 and IL-10 mRNA at the second attack were higher than those at the first attack. Taken together, differential involvement of TNF-alpha and IFN-gamma is closely associated with the clinical features of CR-EAE.

  2. Rsu1 contributes to cell adhesion and spreading in MCF10A cells via effects on P38 map kinase signaling.

    Science.gov (United States)

    Kim, Yong-Chul; Gonzalez-Nieves, Reyda; Cutler, Mary L

    2015-01-01

    The ILK, PINCH, Parvin (IPP) complex regulates adhesion and migration via binding of ILK to β1 integrin and α-parvin thus linking focal adhesions to actin cytoskeleton. ILK also binds the adaptor protein PINCH which connects signaling proteins including Rsu1 to the complex. A recent study of Rsu1 and PINCH1 in non-transformed MCF10A human mammary epithelial cells revealed that the siRNA-mediated depletion of either Rsu1 or PINCH1 decreased the number of focal adhesions (FAs) and altered the distribution and localization of FA proteins. This correlated with reduced adhesion, failure to spread or migrate in response to EGF and a loss of actin stress fibers and caveolae. The depletion of Rsu1 caused significant reduction in PINCH1 implying that Rsu1 may function in part by regulating levels of PINCH1. However, Rsu1, but not PINCH1, was required for EGF-induced activation of p38 Map kinase and ATF2 phosphorylation, suggesting a Rsu1 function independent from the IPP complex. Reconstitution of Rsu1-depleted cells with a Rsu1 mutant (N92D) that does not bind to PINCH1 failed to restore FAs or migration but did promote IPP-independent spreading and constitutive as well as EGF-induced p38 activation. In this commentary we discuss p38 activity in adhesion and how Rsu1 expression may be linked to Map kinase kinase (MKK) activation and detachment-induced stress kinase signaling.

  3. ESR/alanine dosimetry: Study of the kinetics of free radical formation. Evaluation of its contribution to the evolution of the signal after irradiation

    International Nuclear Information System (INIS)

    Dolo, J.M.; Feaugas, V.; Hourdin, L.

    1999-01-01

    CH 3 C HCOOH is commonly accepted as the free radical responsible for the ESR signal detected in alanine after irradiation. The aim of this study is to find out the number of transient species leading to this radical and their kinetics of reaction. To do so, we follow the evolution of the ESR/alanine spectrum shape and correlate the response estimated from the central peak height to the absorbed dose. We use the theory of transformation systems. The first step is to make hypothesis on the number of equivalence classes and their content. From these hypotheses, we model the kinetics of free radical concentrations and check their fitting with experiment. We present comments on these different models, and their consequences on the evolution of the ESR signal on the first days after irradiation. The two successive reaction mechanisms (creation of free radicals and recombination reaction) are compared with the results obtained from a multiparametric study (experimental design) of combined effects (temperature and humidity before and after irradiation) which influence the reaction kinetics. (author)

  4. Basal cell carcinoma is associated with high TNF-alpha release but nor with TNF-alpha polymorphism at position--308

    DEFF Research Database (Denmark)

    Skov, Lone; Allen, Michael H; Bang, Bo

    2003-01-01

    secretion of TNF-alpha has been identified in humans. We have therefore investigated the association of the --308 polymorphism with the risk of basal cell carcinoma (BCC) in humans. The frequency of TNF G and TNF A alleles among Caucasian patients with a previous BCC (n=191) and health adults (n-107) were...... compared. For the TNF--308 polymorphism there was significant association between the genotype or allele frequencies and having BCC. To determine whether patients with a previous BCC had an increased capacity to secrete TNF-alpha, mononuclear cells were stimulated with lipopolysaccharide. Mononuclear cells...... from patients with a previous BCC (n=15) demonstrated a significantly increased release of TNF-alpha upon stimulation with lipopolysaccharide (Pcells age-matched control subjects (n=16). Further studies of other polymorphisms of the TNF-alpha gene associated...

  5. Selective TNF-α inhibitor-induced injection site reactions.

    Science.gov (United States)

    Murdaca, Giuseppe; Spanò, Francesca; Puppo, Francesco

    2013-03-01

    During the last decade, many new biological immune modulators entered the market as new therapeutic principles. TNF-α is a pro-inflammatory cytokine known to a have a key role in the pathogenic mechanisms of various immune-mediated or inflammatory diseases. TNF-α blockers have demonstrated efficacy in large, randomized controlled clinical trials either as monotherapy or in combination with other anti-inflammatory or disease-modifying anti-rheumatic drugs. Although generally well tolerated and safe, potential adverse events may be associated with TNF-α inhibitor treatment. The authors will briefly review the potential adverse drug reactions and the immunological mechanisms of injection site reactions (ISRs) in patients treated with etanercept and adalimumab. Patients treated with TNF-α inhibitors can develop ISR around the sites of injections. 'Type IV delayed type reaction' or 'recall ISRs'. Eosinophilic cellulitis or 'Wells syndrome', 'type III' and 'type I' reactions are reported. Long-term studies are necessary to determine the durability of response and the real risk of ISRs with golimumab and certolizumab pegol. Further studies are also necessary to evaluate the immunogenicity of these drugs.

  6. Immunogenicity of anti-TNF biologic therapies for rheumatoid arthritis

    NARCIS (Netherlands)

    van Schouwenburg, Pauline A.; Rispens, Theo; Wolbink, Gerrit Jan

    2013-01-01

    Currently, five anti-TNF biologic agents are approved for the treatment of rheumatoid arthritis (RA): adalimumab, infliximab, etanercept, golimumab and certolizumab pegol. Formation of anti-drug antibodies (ADA) has been associated with all five agents. In the case of adalimumab and infliximab,

  7. Tumour necrosis factor alpha (TNF-α) genetic polymorphisms and ...

    Indian Academy of Sciences (India)

    Sensitivity analysis of the summary odds ratio coefficients on the association between TNF-α-308G/A polymorphism and AILD risk using a random effects model. (A allele vs G allele). Results were computed by omitting each study in turn. Error bars are 95% confidence interval. Journal of Genetics, Vol. 92, No. 3, December ...

  8. Polimorfismo del TNF-alpha en autoinmunidad y tuberculosis.

    Directory of Open Access Journals (Sweden)

    Paula A. Correa

    2004-06-01

    Full Text Available El factor de necrosis tumoral alfa (TNF-a está incriminado tanto en enfermedades autoinmunes como en infecciosas. En el presente estudio se examinó el polimorfismo de la región promotora -308 del gen del TNF-a en enfermedades autoinmunes [lupus eritematoso sistémico (LES, artritis reumatoidea (AR, síndrome de Sjögren primario (SSp] y en tuberculosis. La genotipificación del polimorfismo -308 del TNF-a se realizó en ADN de pacientes con AR (N=165, LES (N=118, SSp (N=67, tuberculosis (N=138 y controles sanos (N=419, mediante reacción en cadena de la polimerasa con polimorfismos en los tamaños de los fragmentos de restricción (PCR-RFLP. El alelo TNF2 se asoció con la AR (OR=1,6; IC95% 1,2-2,3, p=0,008, el LES (OR=2,3; IC95% 1,6-3,3, p

  9. Concluding remarks: Reflections on the forty year's history of TNF

    International Nuclear Information System (INIS)

    Martin, L.W.

    1994-01-01

    The History of NATO's TNF policy is much wider than it may first appear, for NATO TNF policy has been the heart of the whole nuclear question since shortly after it was first so dramatically posed in 1945. Admittedly the ultimate foundation of deterrence has been the overarching balance of strategic nuclear weapons between the two Superpowers. These have provided the strategic open-quotes monitorclose quotes of ultimately unacceptable damage that inspires cautious behavior at lower levels of conflict. But if the strategic weapons inculcate the caution, it has been with TNF that the opposing blocs have chiefly tried to harness nuclear weapons to particular situations and manipulate them to their advantage. The key characteristic of nuclear weapons that distinguishes them from all others is their virtually unlimited destructive potential. Powers disposing of large strategic nuclear forces cannot readily, perhaps ever, be deprived of an ultimate capacity to do outrageous harm. If they are to be defeated, it must therefore be by outmaneuvering them so that they yield the essential prizes without recourse to their worst possibilities. If nuclear weapons are to be used in this process, whether actually or by latent influence on particular issues, it must be in some limited form. NATO's TNF policy constitutes the best example of this so far in nuclear history

  10. Type I NKT-cell-mediated TNF-α is a positive regulator of NLRP3 inflammasome priming.

    Science.gov (United States)

    Chow, Melvyn T; Duret, Helene; Andrews, Daniel M; Faveeuw, Christelle; Möller, Andreas; Smyth, Mark J; Paget, Christophe

    2014-07-01

    The NLRP3 inflammasome plays a crucial role in the innate immune response to pathogens and exogenous or endogenous danger signals. Its activity must be precisely and tightly regulated to generate tailored immune responses. However, the immune cell subsets and cytokines controlling NLRP3 inflammasome activity are still poorly understood. Here, we have shown a link between NKT-cell-mediated TNF-α and NLRP3 inflammasome activity. The NLRP3 inflammasome in APCs was critical to potentiate NKT-cell-mediated immune responses, since C57BL/6 NLRP3 inflammasome-deficient mice exhibited reduced responsiveness to α-galactosylceramide. Importantly, NKT cells were found to act as regulators of NLRP3 inflammasome signaling, as NKT-cell-derived TNF-α was required for optimal IL-1β and IL-18 production by myeloid cells in response to α-galactosylceramide, by acting on the NLRP3 inflammasome priming step. Thus, NKT cells play a role in the positive regulation of NLRP3 inflammasome priming by mediating the production of TNF-α, thus demonstrating another means by which NKT cells control early inflammation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. TNF Blockade Maintains an IL-10+Phenotype in Human Effector CD4+and CD8+T Cells.

    Science.gov (United States)

    Roberts, Ceri A; Durham, Lucy E; Fleskens, Veerle; Evans, Hayley G; Taams, Leonie S

    2017-01-01

    CD4 + and CD8 + effector T cell subpopulations can display regulatory potential characterized by expression of the prototypically anti-inflammatory cytokine IL-10. However, the underlying cellular mechanisms that regulate expression of IL-10 in different T cell subpopulations are not yet fully elucidated. We recently showed that TNF inhibitors (TNFi) promote IL-10 expression in human CD4 + T cells, including IL-17 + CD4 + T cells. Here, we further characterized the regulation of IL-10 expression via blockade of TNF signaling or other cytokine/co-stimulatory pathways, in human T cell subpopulations. Addition of the TNFi drug adalimumab to anti-CD3-stimulated human CD4 + T cell/monocyte cocultures led to increased percentages of IL-10 + cells in pro-inflammatory IL-17 + , IFNγ + , TNFα + , GM-CSF + , and IL-4 + CD4 + T cell subpopulations. Conversely, exogenous TNFα strongly decreased IL-10 + cell frequencies. TNF blockade also regulated IL-10 expression in CD4 + T cells upon antigenic stimulation. Using time course experiments in whole peripheral blood mononuclear cell (PBMC) cultures, we show that TNF blockade maintained, rather than increased, IL-10 + cell frequencies in both CD4 + and CD8 + T cells following in vitro stimulation in a dose- and time-dependent manner. Blockade of IL-17, IFNγ, IL-6R, or CD80/CD86-mediated co-stimulation did not significantly regulate IL-10 expression within CD4 + or CD8 + T cell subpopulations. We show that TNF blockade acts directly on effector CD4 + T cells, in the absence of monocytes or CD4 + CD25 high CD127 low regulatory T cells and independently of IL-27, resulting in higher IL-10 + frequencies after 3 days in culture. IL-10/IL-10R blockade reduced the frequency of IL-10-expressing cells both in the presence and absence of TNF blockade. Addition of recombinant IL-10 alone was insufficient to drive an increase in IL-10 + CD4 + T cell frequencies in 3-day CD4 + T cell/monocyte cocultures, but resulted in increased IL-10

  12. Activation of phosphatidylinositol 3-kinase/AKT/snail signaling pathway contributes to epithelial-mesenchymal transition-induced multi-drug resistance to sorafenib in hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Jiejie Dong

    Full Text Available Sorafenib, an orally available kinase inhibitor, is the standard first-line systemic drug for advanced hepatocellular carcinoma (HCC, and it exerts potent inhibitory activity against epithelial-mesenchymal transition (EMT and multidrug resistance (MDR by inhibiting mitogen-activated protein kinase (MAPK signaling in HCC. However, after long-term exposure to sorafenib, HCC cells exhibit EMT and resistance to sorafenib. The activation of AKT by sorafenib is thought to be responsible for the development of these characteristics. The present study aims to examine the underlying mechanism and seek potential strategies to reverse this resistance and the progression to EMT. Sorafenib-resistant cells showed increased metastatic and invasive ability, with a higher expression of P-glycoprotein (P-gp, compared with the parental cells. This phenomenon was at least partially due to EMT and the appearance of MDR in sorafenib-resistant HCC cells. Moreover, MDR was a downstream molecular event of EMT. Silencing Snail with siRNA blocked EMT and partially reversed the MDR, thereby markedly abolishing invasion and metastasis in sorafenib-resistant HCC cells, but silencing of MDR1 had no effect on the EMT phenotype. Additionally, HCC parental cells that were stably transfected with pCDNA3.1-Snail exhibited EMT and MDR. Two sorafenib-resistant HCC cell lines, established from human HCC HepG2 and Huh7 cells, were refractory to sorafenib-induced growth inhibition but were sensitive to MK-2206, a novel allosteric AKT inhibitor. Thus, the combination of sorafenib and MK-2206 led to significant reversion of the EMT phenotype and P-gp-mediated MDR by downregulating phosphorylated AKT. These findings underscore the significance of EMT, MDR and enhanced PI3K/AKT signaling in sorafenib-resistant HCC cells.

  13. Bipartite recognition of DNA by TCF/Pangolin is remarkably flexible and contributes to transcriptional responsiveness and tissue specificity of wingless signaling.

    Directory of Open Access Journals (Sweden)

    Hilary C Archbold

    2014-09-01

    Full Text Available The T-cell factor (TCF family of transcription factors are major mediators of Wnt/β-catenin signaling in metazoans. All TCFs contain a High Mobility Group (HMG domain that possesses specific DNA binding activity. In addition, many TCFs contain a second DNA binding domain, the C-clamp, which binds to DNA motifs referred to as Helper sites. While HMG and Helper sites are both important for the activation of several Wnt dependent cis-regulatory modules (W-CRMs, the rules of what constitutes a functional HMG-Helper site pair are unknown. In this report, we employed a combination of in vitro binding, reporter gene analysis and bioinformatics to address this question, using the Drosophila family member TCF/Pangolin (TCF/Pan as a model. We found that while there were constraints for the orientation and spacing of HMG-Helper pairs, the presence of a Helper site near a HMG site in any orientation increased binding and transcriptional response, with some orientations displaying tissue-specific patterns. We found that altering an HMG-Helper site pair from a sub-optimal to optimal orientation/spacing dramatically increased the responsiveness of a W-CRM in several fly tissues. In addition, we used the knowledge gained to bioinformatically identify two novel W-CRMs, one that was activated by Wnt/β-catenin signaling in the prothoracic gland, a tissue not previously connected to this pathway. In sum, this work extends the importance of Helper sites in fly W-CRMs and suggests that the type of HMG-Helper pair is a major factor in setting the threshold for Wnt activation and tissue-responsiveness.

  14. Tidal and Ionospheric Contributions in GUVI O/N2 wave-4 Signals and Implications for F-region Plasma Density Variability

    Science.gov (United States)

    Oberheide, J.; Krier, C. S.; Gan, Q.; Nischal, N.; Zhang, Y.; Chang, L. C.

    2017-12-01

    The longitude/local time modulation of the column number density ratio of atomic oxygen to molecular nitrogen (O/N2 ratio) observed by GUVI/TIMED shows several features that are inconsistent with the known tidal structures in the thermosphere. The zonal wavenumber 4 (wave-4) pattern that is usually associated with the eastward propagating DE3 and SE2 nonmigrating tides is propagating westward and the diagnosed relative O/N2 amplitudes of 5-10% are larger than expected from a thermosphere-tidal coupling perspective. Two recent studies from the GUVI team already established the leading source of the bogus wave-4 tidal signals: ionospheric contamination of the O/N2 ratio derived from GUVI's optical observations caused by radiative O+ recombination in the F-region. However, the apparent westward propagation in the wave-4 GUVI O/N2 ratio remained unexplained since the ionospheric contamination pattern itself is controlled by the DE3 and SE2 tides in the F-region plasma and should thus propagate eastward. This paper revisits the problem by separating the "true" thermospheric tidal signal in the GUVI O/N2 ratio from the ionospheric contamination using the TIMED-based empirical climatological tidal model of the thermosphere (CTMT) and supporting COSMIC TEC tidal diagnostics. As such, it provides new observational information about the impact of tidally-induced composition changes on ionospheric variability. Furthermore, it is shown that the superposition of DE3, SE2, and SPW4 from ionospheric and thermospheric sources produces the apparent westward propagation in O/N2, which will be helpful to interpret the forthcoming GOLD and ICON observations.

  15. TNF-α -238, -308, -863 polymorphisms, and brucellosis infection.

    Science.gov (United States)

    Eskandari-Nasab, Ebrahim; Moghadampour, Mehdi; Sepanj-Nia, Adel

    2016-01-01

    Brucella abortus is an intracellular bacterium that affects humans and domestic animals. Tumor necrosis factor-alpha (TNF-α) has been shown as a key player in the induction of cell-mediated resistance against Brucella infection. We aimed to evaluate the possible influence of the TNF-α promoter polymorphisms (-308 G/A, -238 G/A, and -863 C/A) on the susceptibility of human brucellosis. A total of 153 patients with active brucellosis and 128 healthy individuals were recruited. All subjects were genotyped for the polymorphisms in the TNF-α gene by Allele-Specific polymerase chain reaction analysis. Our results showed that the TNF-α -308 GG genotype was significantly more frequently present in controls than in brucellosis patients (91% vs. 75%), thus was a protective factor against developing brucellosis (OR=0.313, p=0.001). In contrast, the -308 GA genotype (OR=3.026, p=0.002) and minor allele (A) (OR=3.058, p=0.001) as well as AAG haplotype (OR=4.014, p=0.001) conferred an increased risk of brucellosis. However, the -238 G/A and -863 C/A polymorphisms were not associated with the risk of brucellosis at both allelic and genotypic levels (p>0.05). Our study revealed that the TNF-α -308 A allele or GA heterozygosity or AAG haplotype were associated with an increased risk of brucellosis in our population. Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  16. Cloning of Human Tumor Necrosis Factor (TNF) Receptor cDNA and Expression of Recombinant Soluble TNF-Binding Protein

    Science.gov (United States)

    Gray, Patrick W.; Barrett, Kathy; Chantry, David; Turner, Martin; Feldmann, Marc

    1990-10-01

    The cDNA for one of the receptors for human tumor necrosis factor (TNF) has been isolated. This cDNA encodes a protein of 455 amino acids that is divided into an extracellular domain of 171 residues and a cytoplasmic domain of 221 residues. The extracellular domain has been engineered for expression in mammalian cells, and this recombinant derivative binds TNFα with high affinity and inhibits its cytotoxic activity in vitro. The TNF receptor exhibits similarity with a family of cell surface proteins that includes the nerve growth factor receptor, the human B-cell surface antigen CD40, and the rat T-cell surface antigen OX40. The TNF receptor contains four cysteine-rich subdomains in the extra-cellular portion. Mammalian cells transfected with the entire TNF receptor cDNA bind radiolabeled TNFα with an affinity of 2.5 x 10-9 M. This binding can be competitively inhibited with unlabeled TNFα or lymphotoxin (TNFβ).

  17. TNF and LT binding capacities in the plasma of arthritis patients: effect of etanercept treatment in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Gudbrandsdottir, S; Larsen, R; Sørensen, L K

    2004-01-01

    necrosis factor (TNF, previously termed TNF alpha) and lymphotoxin (LT, previously termed TNF beta) may be mediated by etanercept itself as well as by naturally occurring soluble TNF receptors. In light of this, it was of interest to study the total TNF neutralizing capacity in plasma before and during...

  18. TNF-alpha promotes lymphangiogenesis and lymphatic metastasis of gallbladder cancer through the ERK1/2/AP-1/VEGF-D pathway

    International Nuclear Information System (INIS)

    Hong, HaiJie; Jiang, Lei; Lin, YanFei; He, CaiLong; Zhu, GuangWei; Du, Qiang; Wang, XiaoQian; She, FeiFei; Chen, YanLing

    2016-01-01

    Tumor necrosis factor-alpha (TNF-α), a key player in cancer-related inflammation, was recently demonstrated to be involved in the lymphatic metastasis of gallbladder cancer (GBC). Vascular endothelial growth factor D (VEGF-D) is a key lymphangiogenic factor that is associated with lymphangiogenesis and lymph node metastasis in GBC. However, whether VEGF-D is involved in TNF-α-induced lymphatic metastasis of GBC remains undetermined. The expression of VEGF-D in patient specimens was detected by immunohistochemistry and the relationship between VEGF-D in the tissue and TNF-α in the bile of the matching patients was analyzed. The VEGF-D mRNA and protein levels after treatment with exogenous TNF-α in NOZ, GBC-SD and SGC-996 cell lines were measured by real-time PCR and ELISA. The promoter activity and transcriptional regulation of VEGF-D were analyzed with the relative luciferase reporter assay, mutant constructs, electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP) assay, RNA interference and Western blotting. Inhibitors of JNK, p38 MAPK and ERK1/2 were used to explore the upstream signaling effector of AP-1. We used lentiviral vector expressing a VEGF-D shRNA construct to knockdown VEGF-D gene in NOZ and GBC-SD cells. The role of the TNF-α-VEGF-D axis in the tube formation of human dermal lymphatic endothelial cells (HDLECs) was determined using a three-dimensional coculture system. The role of the TNF-α - VEGF-D axis in lymphangiogenesis and lymph node metastasis was studied via animal experiment. TNF-α levels in the bile of GBC patients were positively correlated with VEGF-D expression in the clinical specimens. TNF-α can upregulate the protein expression and promoter activity of VEGF-D through the ERK1/2 - AP-1 pathway. Moreover, TNF-α can promote tube formation of HDLECs, lymphangiogenesis and lymph node metastasis of GBC by upregulation of VEGF-D in vitro and in vivo. Taken together, our data suggest that TNF-α can promote

  19. Tanshinone II A Attenuates TNF-α-Induced Expression of VCAM-1 and ICAM-1 in Endothelial Progenitor Cells by Blocking Activation of NF-κB

    Directory of Open Access Journals (Sweden)

    Jin-Xiu Yang

    2016-11-01

    Full Text Available Background/Aims: Tanshinone IIA (Tan IIA is effective in the treatment of inflammation and atherosclerosis. The adhesion of inflammatory cells to vascular endothelium plays important role in atherogenic processes. This study examined the effects of Tan IIA on expression of adhesion molecules in tumor necrosis factor-α (TNF-α-induced endothelial progenitor cells (EPCs. Methods: EPCs were pretreated with Tan IIA and stimulated with TNF-α. Mononuclear cell (MNC adhesion assay was performed to assess the effects of Tan IIA on TNF-α-induced MNC adhesion. Expression of vascular cell adhesion molecule-1 (VCAM-1/intracellular adhesion molecule-1 (ICAM-1 and activation of Nuclear factor κB (NF-κB signaling pathway were measured. Results: The results showed that the adhesion of MNCs to TNF-α-induced EPCs and expression of VCAM-1/ICAM-1 in EPCs were promoted by TNF-α, which were reduced by Tan IIA. TNF-α increased the amount of phosphorylation of NF-κB, IκB-α and IKKα/β in cytosolic fractions and NF-κB p65 in nucleus, while Tan IIA reduced its amount. Conclusion: This study demonstrated a novel mechanism for the anti-inflammatory/anti-atherosclerotic activity of Tan IIA, which may involve down-regulation of VCAM-1 and ICAM-1 through partial blockage of TNF-α-induced NF-κB activation and IκB-α phosphorylation by the inhibition of IKKα/β pathway in EPCs.

  20. TNF-alpha upregulates expression of BMP-2 and BMP-3 genes in the rat dental follicle--implications for tooth eruption.

    Science.gov (United States)

    Yao, Shaomian; Prpic, Veronica; Pan, Fenghui; Wise, Gary E

    2010-01-01

    The dental follicle appears to regulate both the alveolar bone resorption and bone formation needed for tooth eruption. Tumor necrosis factor-alpha (TNF-alpha) gene expression is maximally upregulated at postnatal day 9 in the rat dental follicle of the first mandibular molar, a time that correlates with rapid bone growth at the base of the tooth crypt, as well as a minor burst of osteoclastogenesis. TNF-alpha expression is correlated with the expression of bone morphogenetic protein-2 (BMP-2), a molecule expressed in the dental follicle that can promote bone formation. Because BMP-2 signaling may be augmented by bone morphogenetic protein-3 (BMP-3), our objective in this study was to determine if the dental follicle expresses BMP-3 and if TNF-alpha stimulates the dental follicle cells to express BMP-2 and BMP-3. Dental follicles were collected from different postnatal ages of rat pups. Dental follicle cells were incubated with TNF-alpha to study its dosage and time-course effects on gene expression of BMP-2 and BMP-3, as determined by real-time RT-PCR. Next, immunostaining was conducted to confirm if the protein was synthesized and ELISA of the conditioned medium was conducted to determine if BMP-2 was secreted. We found that BMP-3 expression is correlated with the expression of TNF-alpha in the dental follicle and TNF-alpha significantly increased BMP-2 and BMP-3 expression in vitro. Immunostaining and ELISA showed that BMP-2 and BMP-3 were synthesized and secreted. This study suggests that TNF-alpha can upregulate the expression of bone formation genes that may be needed for tooth eruption.

  1. TNF-α Upregulates Expression of BMP-2 and BMP-3 Genes in the Rat Dental Follicle – Implications for Tooth Eruption

    Science.gov (United States)

    Yao, Shaomian; Prpic, Veronica; Pan, Fenghui; Wise, Gary E.

    2011-01-01

    The dental follicle appears to regulate both the alveolar bone resorption and bone formation needed for tooth eruption. Tumor necrosis factor-alpha ( TNF-α) gene expression is maximally upregulated at postnatal day 9 in the rat dental follicle of the 1st mandibular molar, a time that correlates with rapid bone growth at the base of the tooth crypt, as well as a minor burst of osteoclastogenesis. TNF-α expression is correlated with the expression of bone morphogenetic protein-2 (BMP-2), a molecule expressed in the dental follicle that can promote bone formation. Because BMP-2 signaling may be augmented by bone morphogenetic protein-3 (BMP-3), it was the objective of this study to determine 1) if the dental follicle expresses BMP-3 and 2) if TNF-α stimulates the dental follicle cells to express BMP-2 and BMP-3. Dental follicles were collected from different postnatal ages of rat pups. Dental follicle cells were incubated with TNF-α to study its dosage and time-course effects on gene expression of BMP-2 and BMP-3, as determined by real-time RT-PCR. Next, immunostaining was conducted to confirm if the protein was synthesized and ELISA of the conditioned medium was conducted to determine if BMP-2 was secreted. We found that BMP-3 expression is correlated with the expression of TNF-α in the dental follicle and TNF-α significantly increased BMP-2 and BMP-3 expression in vitro. Immunostaining and ELISA showed that BMP-2 and BMP-3 were synthesized and secreted. This study suggests that TNF-α can upregulate the expression of bone formation genes that may be needed for tooth eruption. PMID:20067418

  2. Allosteric signaling through an mGlu2 and 5-HT2A heteromeric receptor complex and its potential contribution to schizophrenia.

    Science.gov (United States)

    Moreno, José L; Miranda-Azpiazu, Patricia; García-Bea, Aintzane; Younkin, Jason; Cui, Meng; Kozlenkov, Alexey; Ben-Ezra, Ariel; Voloudakis, Georgios; Fakira, Amanda K; Baki, Lia; Ge, Yongchao; Georgakopoulos, Anastasios; Morón, José A; Milligan, Graeme; López-Giménez, Juan F; Robakis, Nikolaos K; Logothetis, Diomedes E; Meana, J Javier; González-Maeso, Javier

    2016-01-12

    Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) can form multiprotein complexes (heteromers), which can alter the pharmacology and functions of the constituent receptors. Previous findings demonstrated that the Gq/11-coupled serotonin 5-HT2A receptor and the Gi/o-coupled metabotropic glutamate 2 (mGlu2) receptor-GPCRs that are involved in signaling alterations associated with psychosis-assemble into a heteromeric complex in the mammalian brain. In single-cell experiments with various mutant versions of the mGlu2 receptor, we showed that stimulation of cells expressing mGlu2-5-HT2A heteromers with an mGlu2 agonist led to activation of Gq/11 proteins by the 5-HT2A receptors. For this crosstalk to occur, one of the mGlu2 subunits had to couple to Gi/o proteins, and we determined the relative location of the Gi/o-contacting subunit within the mGlu2 homodimer of the heteromeric complex. Additionally, mGlu2-dependent activation of Gq/11, but not Gi/o, was reduced in the frontal cortex of 5-HT2A knockout mice and was reduced in the frontal cortex of postmortem brains from schizophrenic patients. These findings offer structural insights into this important target in molecular psychiatry. Copyright © 2016, American Association for the Advancement of Science.

  3. Downregulation of miR-218 contributes to epithelial-mesenchymal transition and tumor metastasis in lung cancer by targeting Slug/ZEB2 signaling.

    Science.gov (United States)

    Shi, Z-M; Wang, L; Shen, H; Jiang, C-F; Ge, X; Li, D-M; Wen, Y-Y; Sun, H-R; Pan, M-H; Li, W; Shu, Y-Q; Liu, L-Z; Peiper, S C; He, J; Jiang, B-H

    2017-05-04

    Epithelial-mesenchymal transition (EMT) has been recognized as a key element of cell migration and invasion in lung cancer; however, the underlying mechanisms are not fully elucidated. Recently, emerging evidence suggest that miRNAs have crucial roles in control of EMT and EMT-associated traits such as migration, invasion and chemoresistance. Here, we found that miR-218 expression levels were significantly downregulated in lung cancer tissues compared with adjacent non-cancerous tissues, and the levels of miR-218 were significantly associated with histological grades and lymph node metastasis. Overexpression of miR-218 inhibited cell migration and invasion as well as the EMT process. Of particular importance, miR-218 was involved in the metastatic process of lung cancer cells in vivo by suppressing local invasion and distant colonization. We identified Slug and ZEB2 as direct functional targets of miR-218. Inverse correlations were observed between miR-218 levels and Slug/ZEB2 levels in cancer tissue samples. In addition, overexpression of miR-218 in H1299 increased chemosensitivity of cells to cisplatin treatment through suppression of Slug and ZEB2. These findings highlight an important role of miR-218 in the regulation of EMT-related traits and metastasis of lung cancer in part by modulation of Slug/ZEB2 signaling, and provide a potential therapeutic strategy by targeting miR-218 in NSCLC.

  4. TNF-α -308 G>A polymorphism and risk of bone marrow failure syndrome: A meta-analysis.

    Science.gov (United States)

    Chen, Wancheng; Zhu, Haili; Yu, Lili; Lu, Ziyuan; Yao, Zhuoxin; Xiao, Yang

    2015-07-01

    The influence of the TNF-α -308 G>A polymorphism on bone marrow failure syndrome susceptibility is unclear. We have conducted a meta-analysis of all relevant published studies. We searched PubMed, Chinese Biomedical Literature and China National Knowledge Infrastructure databases up to February 2015. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of associations. Eleven case-control studies with a total sample size of 909 cases and 1803 controls were eligible to assess the association between the TNF-α -308 G>A polymorphism and susceptibility to bone marrow failure syndrome. Overall, the TNF-α -308 G>A polymorphism was significantly associated with an increased risk of bone marrow failure syndrome in any genetic model. In stratified analysis by disease type, there was a significant association between the TNF-α -308 G>A polymorphism and increased risk of aplastic anemia but no significant association with myelodysplastic syndrome (AA vs. GG: OR=2.23, 95% CI=1.23-4.05, P=0.006; recessive model: OR=3.52, 95% CI=1.30-9.53, P=0.010). In subgroup analysis by ethnicity, there were significant associations between the TNF-α -308 G>A polymorphism and increased risk of bone marrow failure syndrome for Caucasians in two models, but not in Asian populations (AA vs. GG: OR=2.66, 95% CI=1.36-5.21, P=0.003; recessive model: OR=2.68, 95% CI=1.37-5.24, P=0.002). In conclusion, our meta-analysis suggests that the TNF-α -308 G>A polymorphism may contribute to the risk of bone marrow failure syndrome, particularly among Caucasian and aplastic anemia patients. Further investigations are needed to clarify the role of the TNF-α -308 G>A polymorphism in bone marrow failure syndrome. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. TNF-α inhibitory effect of Euphorbia hirta in rats.

    Science.gov (United States)

    Ahmad, Sheikh Fayaz; Bani, Sarang; Sultan, Phalisteen; Ali, Sheikh Abid; Bakheet, Saleh A; Attia, Sabry M; Abd-Allah, Adel R A

    2013-04-01

    Euphorbia hirta L. (Euphorbiaceae) (E. hirta) is a tree locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, respiratory ailments, tumors, and wounds, and it has reported antiallergic, antipyretic, anti-inflammatory activities, etc. This study evaluated the ability of fresh leaves of E. hirta ethanol extract to inhibit the intracellular tumor necrosis factor α (TNF-α) level in the synovial fluid and neutrophils in lipopolysaccharide (LPS)-induced inflamed rat knees. Female Wister albino rats 140-160 g were used. E. hirta ethanol extract was given orally at 25, 50, 100, and 200 mg/kg, 2 h before an intra-articular (i.a.) injection of LPS. Two and three hours later, synovial fluid and neutrophils levels of intracellular TNF-α production were measured. In the time course of the experiment, E. hirta maximum inhibition at 100 and 200 mg/kg (p.o.) dose showed 16.5 ± 1.34 and 14.4 ± 1.30% of synovial fluid, 4.26 ± 0.36 and 3.78 ± 0.29% of neutrophils levels of intracellular TNF-α productions at 2 h after LPS injection. LPS control displayed 22.97 ± 1.61 and 6.78 ± 0.34% of synovial fluid and neutrophils levels of intracellular TNF-α at 2 h after LPS injection. Intracellular TNF-α was also estimated at 3 h after LPS injection. The LPS-injected rat knee model gives a comparative study of acute anti-inflammatory responses. E. hirta inhibition of proinflammatory intracellular cytokine TNF-α production with LPS-induced inflamed rat knee is of great importance in defining the anti-arthritic potential of E. hirta.

  6. Defective glucocorticoid receptor signaling and keratinocyte-autonomous defects contribute to skin phenotype of mouse embryos lacking the Hsp90 co-chaperone p23.

    Directory of Open Access Journals (Sweden)

    Marta Madon-Simon

    Full Text Available p23 is a small acidic protein with intrinsic molecular chaperone activity. It is best known as a co-chaperone of the major cytosolic molecular chaperone Hsp90. p23 binds the N-terminus of Hsp90 and stabilizes the ATP-bound and N-terminally closed Hsp90 dimer. It is in this configuration that many Hsp90 clients are most stably bound. Considering the important role of p23 in the Hsp90 cycle, it came as a surprise that it is not absolutely essential for viability in the budding yeast or for mouse development. Mice without p23 develop quite normally until birth and then all die perinatally because of immature lungs. The only other apparent phenotype of late stage embryos and newborns is a skin defect, which we have further characterized here. We found that skin differentiation is impaired, and that both apoptosis and cell proliferation are augmented in the absence of p23; the consequences are a severe thinning of the stratum corneum and reduced numbers of hair follicles. The altered differentiation, spontaneous apoptosis and proliferation are all mimicked by isolated primary keratinocytes indicating that they do require p23 functions in a cell-autonomous fashion. Since the phenotype of p23-null embryos is strikingly similar to that of embryos lacking the glucocorticoid receptor, a paradigmatic Hsp90-p23 client protein, we investigated glucocorticoid signaling. We discovered that it is impaired in vivo and for some aspects in isolated keratinocytes. Our results suggest that part of the phenotype of p23-null embryos can be explained by an impact on this particular Hsp90 client, but do not exclude that p23 by itself or in association with Hsp90 affects skin development and homeostasis through yet other pathways.

  7. Activation of ERK signalling by Src family kinases (SFKs) in DRG neurons contributes to hydrogen peroxide (H2O2)-induced thermal hyperalgesia.

    Science.gov (United States)

    Singh, Ajeet Kumar; Vinayak, Manjula

    2017-10-01

    Concomitant generation of reactive oxygen species during tissue inflammation has been recognised as a major factor for the development and the maintenance of hyperalgesia, out of which H 2 O 2 is the major player. However, molecular mechanism of H 2 O 2 induced hyperalgesia is still obscure. The aim of present study is to analyse the mechanism of H 2 O 2 -induced hyperalgesia in rats. Intraplantar injection of H 2 O 2 (5, 10 and 20 µmoles/paw) induced a significant thermal hyperalgesia in the hind paw, confirmed by increased c-Fos activity in dorsal horn of spinal cord. Onset of hyperalgesia was prior to development of oxidative stress and inflammation. Rapid increase in phosphorylation of extracellular signal regulated kinase (ERK) was observed in neurons of dorsal root ganglia after 20 min of H 2 O 2 (10 µmoles/paw) administration, which gradually returned towards normal level within 24 h, following the pattern of thermal hyperalgesia. The expression of TNFR1 followed the same pattern and colocalised with pERK. ERK phosphorylation was observed in NF-200-positive and -negative neurons, indicating the involvement of ERK in C-fibres as well as in A-fibres. Intrathecal preadministration of Src family kinases (SFKs) inhibitor (PP1) and MEK inhibitor (PD98059) prevented H 2 O 2 induced augmentation of ERK phosphorylation and thermal hyperalgesia. Pretreatment of protein tyrosine phosphatases (PTPs) inhibitor (sodium orthovanadate) also diminished hyperalgesia, although it further increased ERK phosphorylation. Combination of orthovanadate with PP1 or PD98059 did not exhibit synergistic antihyperalgesic effect. The results demonstrate SFKs-mediated ERK activation and increased TNFR1 expression in nociceptive neurons during H 2 O 2 induced hyperalgesia. However, the role of PTPs in hyperalgesic behaviour needs further molecular analysis.

  8. Pro-inflammatory cytokine TNF-α is a key inhibitory factor for lactose synthesis pathway in lactating mammary epithelial cells.

    Science.gov (United States)

    Kobayashi, Ken; Kuki, Chinatsu; Oyama, Shoko; Kumura, Haruto

    2016-01-15

    Lactose is a milk-specific carbohydrate synthesized by mammary epithelial cells (MECs) in mammary glands during lactation. Lactose synthesis is downregulated under conditions causing inflammation such as mastitis, in which MECs are exposed to high concentrations of inflammatory cytokines. In this study, we investigated whether inflammatory cytokines (TNF-α, IL-1β, and IL-6) directly influence the lactose synthesis pathway by using two types of murine MEC culture models: the monolayer culture of MECs to induce lactogenesis; and the three-dimensional culture of MECs surrounded by Matrigel to induce reconstitution of the alveolar structure in vitro. TNF-α caused severe down-regulation of lactose synthesis-related genes concurrently with the degradation of glucose transporter 1 (GLUT1) from the basolateral membranes in MECs. IL-1β also caused degradation of GLUT1 along with a decrease in the expression level of β-1,4-galactosylransferase 3. IL-6 caused both up-regulation and down-regulation of the expression levels of lactose synthesis-related genes in MECs. These results indicate that TNF-α, IL-1β, and IL-6 have different effects on the lactose synthesis pathway in MECs. Furthermore, TNF-α triggered activation of NFκB and inactivation of STAT5, suggesting that NFκB and STAT5 signaling pathways are involved in the multiple adverse effects of TNF-α on the lactose synthesis pathway. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Reduction of CD19 autoimmunity marker on B cells of paediatric SLE patients through repressing PU.1/TNF-α/BAFF axis pathway by miR-155.

    Science.gov (United States)

    Aboelenein, H R; Hamza, M T; Marzouk, H; Youness, R A; Rahmoon, M; Salah, S; Abdelaziz, A I

    2017-06-01

    microRNA-155 (miR-155) is implicated in regulating B-cell activation and survival that is important in systemic lupus erythematosus (SLE) pathogenesis. PU.1, a target for miR-155, is a crucial regulator of B-cell development and enhances Tumour-Necrosis-factor-alpha (TNF-α) expression. TNF-α induces the expression of B-cell-activating-factor (BAFF). BAFF is reported to increase the expression of the autoimmunity marker; CD19. This study aimed to investigate the regulation of expression of PU.1 in pediatric-systemic-lupus-erythematosus (pSLE) patients by miR-155, and hence evaluate its impact on TNF-α/BAFF/CD19 signalling pathway. Screening revealed that PU.1 is upregulated in PBMCs and B-cells of pSLE patients. PU.1 expression directly correlated with systemic-lupus-erythematosus disease-activity-index-2 K SLEDAI-2K. Ectopic expression of miR-155 and knockdown of PU.1 suppressed PU.1, TNF-α and BAFF. Finally, miR-155 decreased the proportion of BAFF-expressing-B-cells and CD19 protein expression. These findings suggest that miR-155 suppresses autoimmunity through transcriptional repression of PU.1 and TNF-α, which in turn suppresses BAFF and CD19 protein expression.

  10. Sequestration of NF-kappaB signaling complexes in lipid rafts contributes to repression of NF-kappaB in T lymphocytes under hyperthermia stress.

    Science.gov (United States)

    Yan, Guang; Huang, Jiannan; Jarbadan, Nancy Ruth; Jiang, Yixing; Cheng, Hua

    2008-05-02

    Sepsis causes extensive apoptosis of lymphocytes, a pathological condition that is frequently associated with hyperthermia. Heat stress has been implicated to repress the activation of an inflammatory mediator, nuclear factor of kappaB (NF-kappaB), which sensitizes cells to apoptosis mediated by inflammatory cytokine, tumor necrosis factor alpha. However, the molecular mechanism of hyperthermia-associated loss of T cells remains unclear. We show that hyperthermia causes rapid translocation of IkappaB kinase (IKK) and NF-kappaB complexes into the plasma membrane-associated lipid rafts in T cells. Heat stress induces aggregation of Carma1 in lipid rafts, which in turn recruits protein kinase C theta (PKC theta) and Bcl10 to the microdomains, causing subsequent membrane translocation of the IKK and NF-kappaB signalosomes. Depletion of Carma1 and inhibition of PKC theta impair accumulation of NF-kappaB complexes in lipid rafts. Heat stress prohibits IkappaB kinase activity by sequestrating the IKK and NF-kappaB complexes in lipid rafts and by segregating the chaperone protein Hsp90, an essential cofactor for IKK, from the IKK complex. This process ultimately results in functional deficiency of NF-kappaB and renders T cells resistant to tumor necrosis factor alpha-induced activation of IKK, thereby contributing to the apoptotic loss of T lymphocytes in sepsis-associated hyperthermia.

  11. Circulating tumour necrosis factor alpha & soluble TNF receptors in patients with Guillain-Barre syndrome.

    Science.gov (United States)

    Radhakrishnan, V V; Sumi, M G; Reuben, S; Mathai, A; Nair, M D

    2003-05-01

    Tumour necrosis factor-alpha (TNF-alpha) is regarded as one of the immune factors that can induce demyelination of peripheral nerves in patients with Guillian-Barre syndrome (GBS). This present study was undertaken to find out the role of TNF-alpha and soluble TNF receptors in the pathogenesis of GBS; and to study the effect of intravenous immunoglobulin (ivIg) therapy on the serum TNF-alpha and soluble TNF receptors in patients with GBS. Thirty six patients with GBS in progressive stages of motor weakness were included in this study. The serum TNF-alpha and soluble TNF receptors (TNF-RI, TNF-RII) were measured in the serum samples of these patients before and after ivIg therapy by a sandwich ELISA. Of the 36 patients with GBS, 26 (72.2%) showed elevated serum TNF-alpha levels prior to ivIg therapy. Following a complete course of ivIg therapy there was a progressive decrease in the serum TNF-alpha concentrations in these 26 patients. On the other hand, the soluble TNF receptors, particularly TNF-RII showed an increase in the serum of GBS patients following ivIg therapy. The results indicate that ivIg reduces the serum TNF-alpha concentrations in the GBS patients having elevated levels prior to ivIg therapy. Elevated serum levels of soluble TNF receptors following ivIg therapy may play a protective role by inhibiting the demyelinating effect of TNF-alpha in the peripheral nerves of patients with GBS.

  12. Protective effect of chlorpromazine on TNF-mediated hapten-induced irritant reaction.

    Science.gov (United States)

    Erroi, A; Fantuzzi, G; Demitri, M T; Echtenacher, B; Gnocchi, P; Isetta, A; Ghezzi, P

    1995-01-01

    Picryl chloride-induced irritant reaction (IR) was shown to be mediated by tumor necrosis factor (TNF). Anti-TNF monoclonal antibodies, but not interleukin 1 receptor antagonist (IL-1 Ra), had a protective effect. Chlorpromazine (CPZ), an inhibitor of TNF synthesis, protected against IR and inhibited the IR-associated TNF induction in ear homogenates. Investigation of the role of polymorphonuclear leukocyte (PMN) in neutropenic mice showed that neutropenia did not prevent the development of the IR.

  13. TNF Lectin-Like Domain Restores Epithelial Sodium Channel Function in Frameshift Mutants Associated with Pseudohypoaldosteronism Type 1B

    Directory of Open Access Journals (Sweden)

    Anita Willam

    2017-05-01

    abundance varied between mutants. Solnatide restored function in α-ENaC frameshift mutants to current density levels of wild type ENaC or higher despite their lacking a binding site for solnatide, previously located to the region between TM2 and the C-terminus of the α-subunit. TNF similarly restored current density to wild type levels in the mutant αR448fs. Activation of βγ-ENaC may contribute to this moderate current enhancement, but whatever the mechanism, experimental data indicate that solnatide could be a new strategy to treat PHA1B.

  14. Insights into deregulated TNF and IL-10 production in malaria

    DEFF Research Database (Denmark)

    Boeuf, Philippe S; Loizon, Séverine; Awandare, Gordon A

    2012-01-01

    ABSTRACT: BACKGROUND: Severe malarial anaemia (SMA) is a major life-threatening complication of paediatric malaria. Protracted production of pro-inflammatory cytokines promoting erythrophagocytosis and depressing erythropoiesis is thought to play an important role in SMA, which is characterized...... the activation status of those cells in SMA patients. METHODS: The IL-10 and TNF production capacity and the activation phenotype of monocytes and T cells were compared in samples collected from 332 Ghanaian children with non-overlapping SMA (n = 108), cerebral malaria (CM) (n = 144) or uncomplicated malaria (UM......) (n = 80) syndromes. Activation status of monocytes and T cells was ascertained by measuring HLADR + and/or CD69+ surface expression by flow cytometry. The TNF and IL-10 production was assessed in a whole-blood assay after or not stimulation with lipopolysaccharide (LPS) or phytohaemaglutinin (PHA...

  15. Gingival crevicular fluid and serum levels of APRIL, BAFF and TNF-alpha in rheumatoid arthritis and osteoporosis patients with periodontal disease.

    Science.gov (United States)

    Gümüş, Pinar; Buduneli, Eralp; Biyikoğlu, Başak; Aksu, Kenan; Saraç, Fulden; Buduneli, Nurcan; Lappin, David F

    2013-10-01

    This study was performed to evaluate gingival crevicular fluid (GCF) and serum levels of a proliferation inducing ligand (APRIL) and B cell activating factor (BAFF) and compare this to differences between TNF-alpha levels in rheumatoid arthritis (RA), osteoporosis (OPR) and systemically healthy women with periodontal disease (SH). Gingival crevicular fluid (GCF) and serum samples were obtained before any periodontal intervention from 17 RA, 19 OPR patients and 13 SH women with periodontitis. Full-mouth clinical periodontal measurements were recorded. APRIL, BAFF and TNF-α levels were determined by ELISA. Statistical analysis was performed using multivariate analysis, ANOVA and Spearman correlation. Pocket depths differed in site-specific comparisons, but otherwise clinical measurements were similar in the three study groups. Multivariate least squares regression ANOVA adjusted for age and for plaque index indicated that total amounts of TNF-α and concentrations of TNF-α, BAFF and APRIL were significantly greater in the RA patients than in the SH group (p<0.05), and GCF concentrations of BAFF were greater in OPR patients than in SH. Serum TNF-α and BAFF were significantly higher in the RA group compared to SH (p<0.05) and serum TNF-α was greater in RA than in OPR (p<0.05). APRIL and BAFF correlated with RANKL levels in GCF and serum (p<0.05). Despite long-term usage of anti-inflammatory drugs in the RA and OPR patients, increased TNF-family cytokines, might suggest that these patients have a propensity to overproduce these inflammatory mediators but whether this results from greater disease activity or contribute to greater disease activity remains moot. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Cinnamon Extract Improves TNF-a Induced Overproduction of Intestinal ApolipoproteinB-48 Lipoproteins

    Science.gov (United States)

    TNF-alpha stimulates the overproduction of intestinal apolipoproteins. We evaluated whether a water extract of cinnamon (Cinnulin PF®) improved the dyslipidemia induced by TNF-alpha in Triton WR-1339 treated hamsters, and whether Cinnulin PF® inhibits the TNF-alpha-induced over the secretion of apoB...

  17. Receptor-Mediated and Lectin-Like Activities of Carp (Cyprinus carpio) TNF-¿

    NARCIS (Netherlands)

    Forlenza, M.; Magez, S.; Scharsack, J.P.; Westphal, A.H.; Savelkoul, H.F.J.; Wiegertjes, G.F.

    2009-01-01

    Functional characterization of TNF- in species other than mammalian vertebrates is limited, and TNF- has been studied in a limited number of fish species, primarily in vitro using recombinant proteins. Studies on TNF- from different fish species so far pointed to several inconsistencies, in

  18. Improved survival of TNF-deficient mice during the zymosan-induced multiple organ dysfunction syndrome.

    NARCIS (Netherlands)

    Volman, T.J.H.; Hendriks, T.; Verhofstad, A.A.J.; Kullberg, B.J.; Goris, R.J.A.

    2002-01-01

    The purpose of the study was to investigate the course of the zymosan-induced multiple organ dysfunction syndrome (MODS) in the absence of tumor necrosis factor (TNF) in a murine model. Tumor Necrosis Factor-alpha-lymphotoxin-a knockout (TNF/LT-/-) mice (n = 36) and wild-type (TNF/LT+/+) mice (n =

  19. Tumor necrosis factor alpha (TNF alpha) in human skin : A comparison of different antibodies for immunohistochemistry

    NARCIS (Netherlands)

    van der Laan, N; de Leij, LFMH; Buurman, W; Timens, W; ten Duis, HJ

    Conflicting results have been reported regarding the localization and presence of TNF alpha in normal human skin, To study TNF alpha expression, we tested a panel of antibodies directed against human TNF alpha, First, antibodies were tested for immunoreactivity on cytospots of isolated

  20. Tailored anti-TNF therapy during pregnancy in patients with IBD : Maternal and fetal safety

    NARCIS (Netherlands)

    de Lima, A.; Zelinkova, Z.; van der Ent, C.; Steegers, E. A P; van der Woude1, C. J.

    Objective Antitumour necrosis factor (TNF) during pregnancy in patients with IBD is related to high fetal anti-TNF levels. We evaluated maternal and child safety on discontinuing anti-TNF in the second trimester of pregnancy. Design Two groups of women with IBD were prospectively followed-up during

  1. Tailored anti-TNF therapy during pregnancy in patients with IBD: Maternal and fetal safety

    NARCIS (Netherlands)

    A. de Lima (Alison); Z. Zelinkova (Zuzana); C. van der Ent (Cokkie); E.A.P. Steegers (Eric); van der Woude1, C.J.

    2016-01-01

    textabstractObjective Antitumour necrosis factor (TNF) during pregnancy in patients with IBD is related to high fetal anti-TNF levels. We evaluated maternal and child safety on discontinuing anti-TNF in the second trimester of pregnancy. Design Two groups of women with IBD were prospectively

  2. TNF receptor 1 genetic risk mirrors outcome of anti-TNF therapy in multiple sclerosis

    DEFF Research Database (Denmark)

    Gregory, Adam P; Dendrou, Calliope A; Attfield, Kathrine E

    2012-01-01

    Although there has been much success in identifying genetic variants associated with common diseases using genome-wide association studies (GWAS), it has been difficult to demonstrate which variants are causal and what role they have in disease. Moreover, the modest contribution that these varian...

  3. Structural and functional characterization of a novel molluskan ortholog of TRAF and TNF receptor-associated protein from disk abalone (Haliotis discus discus).

    Science.gov (United States)

    Lee, Youngdeuk; Elvitigala, Don Anushka Sandaruwan; Whang, Ilson; Lee, Sukkyoung; Kim, Hyowon; Zoysa, Mahanama De; Oh, Chulhong; Kang, Do-Hyung; Lee, Jehee

    2014-09-01

    Immune signaling cascades have an indispensable role in the host defense of almost all the organisms. Tumor necrosis factor (TNF) signaling is considered as a prominent signaling pathway in vertebrate as well as invertebrate species. Within the signaling cascade, TNF receptor-associated factor (TRAF) and TNF receptor-associated protein (TTRAP) has been shown to have a crucial role in the modulation of immune signaling in animals. Here, we attempted to characterize a novel molluskan ortholog of TTRAP (AbTTRAP) from disk abalone (Haliotis discus discus) and analyzed its expression levels under pathogenic stress. The complete coding sequence of AbTTRAP consisted of 1071 nucleotides, coding for a 357 amino acid peptide, with a predicted molecular mass of 40 kDa. According to our in-silico analysis, AbTTRAP resembled the typical TTRAP domain architecture, including a 5'-tyrosyl DNA phosphodiesterase domain. Moreover, phylogenetic analysis revealed its common ancestral invertebrate origin, where AbTTRAP was clustered with molluskan counterparts. Quantitative real time PCR showed universally distributed expression of AbTTRAP in selected tissues of abalone, from which more prominent expression was detected in hemocytes. Upon stimulation with two pathogen-derived mitogens, lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (poly I:C), transcript levels of AbTTRAP in hemocytes and gill tissues were differentially modulated with time. In addition, the recombinant protein of AbTTRAP exhibited prominent endonuclease activity against abalone genomic DNA, which was enhanced by the presence of Mg(2+) in the medium. Collectively, these results reinforce the existence of the TNF signaling cascade in mollusks like disk abalone, further implicating the putative regulatory behavior of TTRAP in invertebrate host pathology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Clinical management of paradoxical psoriasiform reactions during TNF- α therapy.

    Science.gov (United States)

    Navarro, R; Daudén, E

    2014-10-01

    There have been reports of paradoxical induction or worsening of psoriasis during treatment with tumor necrosis factor (TNF) α agents (infliximab, etanercept, adalimumab, and certolizumab). It has been hypothesized that an imbalance between TNF-α and interferon α might have a role in the etiology and pathogenesis of these reactions. Paradoxical psoriasiform reactions can be divided clinically into de novo psoriasis and exacerbation of preexisting psoriasis. The first, which is more common and more extensively described in the literature, occurs in patients without a history of psoriasis who are receiving TNF-α therapy for another inflammatory disorder. The second can occur with or without changes in the morphology of the lesions. In this article, we review the literature on the clinical and histologic features of paradoxical psoriasiform reactions, analyze their clinical course and treatment, and propose a clinical management model for use in routine practice. Copyright © 2012 Elsevier España, S.L.U. and AEDV. All rights reserved.

  5. Transport experience of new ''TNF-XI'' powder package

    International Nuclear Information System (INIS)

    Nomura, I.; Fujiwara, T.; Naigeon, P.

    2004-01-01

    Since the Tokai criticality accident in 1999, there has been no specialized manufacturer conducting uranium re-conversion in Japan. For this reason, Nuclear Fuel Industries, Ltd. (NFI) imports from overseas almost all the uranium oxide powder used for manufacturing pellets for nuclear fuel assemblies. To date, an NT-IX package has been used for transporting the uranium oxide powder. However, due to the adoption of IAEA TS-R-1 into Japanese domestic regulations, we have begun to use a new TNF-XI powder package because the NT-IX package can suffer major deformation under the drop test III condition. The TNF-XI package was jointly developed by COGEMA LOGISTICS of France and NFI from 2000, and started to be used for actual transportation in 2003. This package has improved transport efficiency, handling operability and safety performance in comparison to its predecessor. This paper describes the characteristics of the new TNF-XI package and its actual transportation records and performance

  6. Analysis of TNF-α (-308) polymorphism and gingival crevicular fluid TNF-α levels in aggressive and chronic periodontitis: A preliminary report.

    Science.gov (United States)

    Özer Yücel, Özlem; Berker, Ezel; Mesci, Lütfiye; Eratalay, Kenan; Tepe, Eser; Tezcan, İlhan

    2015-04-01

    The purpose of this study was to determine the differences in the distribution of TNF-α (-308) gene polymorphism among aggressive periodontitis, chronic periodontitis and periodontally healthy individuals and also to investigate whether this polymorphism is associated with gingival crevicular fluid TNF-α levels and periodontal disease severity. A total of 93 individuals were enrolled in the study including 38 aggressive periodontitis, 29 chronic periodontitis patients, and 26 healthy controls. Single nucleotide polymorphism at TNF-α (-308) is analyzed by PCR-RFLP method. Gingival crevicular fluid samples were analyzed for TNF-α, using ELISA. The distribution of genotypes and allele frequencies for TNF-α (-308) were similar among the groups. After stratification of patients with respect to attachment level, aggressive periodontitis patients with clinical attachment level ⩾4mm was observed to have a higher frequency of TNF-α (-308) allele 2 compared to the chronic periodontitis patients with clinical attachment level ⩾4mm. No significant differences were found between the TNF-α levels of the different genotypes in spite of an insignificant increase in patient groups carrying TNF-α (-308) allele 2. The results of this study revealed an association between TNF-α (-308) allele 2 frequency and aggressive periodontitis patients with clinical attachment level ⩾4mm in the population studied. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Secukinumab efficacy in anti-TNF-naive and anti-TNF-experienced subjects with active ankylosing spondylitis: results from the MEASURE 2 Study.

    Science.gov (United States)

    Sieper, Joachim; Deodhar, Atul; Marzo-Ortega, Helena; Aelion, Jacob A; Blanco, Ricardo; Jui-Cheng, Tseng; Andersson, Mats; Porter, Brian; Richards, Hanno B

    2017-03-01

    There is significant unmet need in patients with ankylosing spondylitis (AS) who have inadequate response or intolerance to anti-tumour necrosis factor (TNF) treatment. Secukinumab, an anti-interleukin-17A monoclonal antibody, significantly improved signs and symptoms of AS in the MEASURE 2 study (NCT01649375). Subjects with active AS (N=219) received secukinumab (150 or 75 mg) or placebo at baseline, weeks 1, 2, 3 and 4, and every 4 weeks thereafter. Randomisation was stratified by prior anti-TNF use: anti-TNF-naive or inadequate response/intolerance to one anti-TNF (anti-TNF-IR). The primary endpoint was Assessment of SpondyloArthritis International Society criteria (ASAS) 20 at week 16. At week 16, 68.2% of anti-TNF-naive subjects treated with secukinumab 150 mg achieved ASAS20 compared with 31.1% treated with placebo (pTNF-IR group, 50.0% of subjects treated with secukinumab 150 mg achieved an ASAS20 response compared with 24.1% treated with placebo (pTNF-naive and anti-TNF-IR subjects through 52 weeks of therapy. NCT01649375. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Down-regulation of surface receptors for TNF and IL-1 on circulating monocytes and granulocytes during human endotoxemia: effect of neutralization of endotoxin-induced TNF activity by infusion of a recombinant dimeric TNF receptor

    NARCIS (Netherlands)

    van der Poll, T.; Coyle, S. M.; Kumar, A.; Barbosa, K.; Agosti, J. M.; Lowry, S. F.

    1997-01-01

    Leukocytes rapidly lose their surface receptors for TNF and IL-1 upon exposure to various stimuli in vitro. We sought to determine by FACS analysis changes in the expression of TNF receptors (TNFR) and type II IL-1R on circulating monocytes and granulocytes during endotoxemia in vivo, and the role

  9. ¿(Anti-TNF-¿ y tuberculosis pulmonar

    Directory of Open Access Journals (Sweden)

    Carlo Vinicio Caballero Uribe

    2006-01-01

    Full Text Available Presentación de una paciente con artritis reumatoide severa en tratamiento con inhibidores del Factor de Necrosis Tumoral (Anti-TNF, quien presenta además un cuadro de tuberculosis pulmonar. La artritis reumatoide es una enfermedad inflamatoria crónica de las articulaciones, que afecta en un inicio la membrana sinovial, pero que si no es tratada oportunamente lleva a daño estructural irreversible del sistema músculo-esquelético y eventualmente de otros sistemas orgánicos. Dentro de los criterios de la American College of Rheumatology se incluyen la Rigidez Matutina, Artritis de 3 o más articulaciones, Artritis simétrica, Nódulos reumáticos, Factor Reumatoideo y hallazgos radiográficos. Dentro de la patogenia de esta enfermedad, el Factor de Necrosis Tumoral es una citocina que juega un papel importante, una producción elevada de TNF-α se ha encontrado en la sinovial de estos pacientes, y por su capacidad de inducir la producción de otras citocinas, como IL-6, IL-17, GM-CSF, M-CSF, e incluso IL-1 y TNF-α (función autócrina, parecería que el TNF-α ejerce una acción “jerárquica” dentro de la llamada red de citocinas y una inhibición de su acción da como resultado un beneficio terapéutico en los pacientes con AR. Sin embargo, es conocido que la infección concurrente más frecuentemente informada con el uso de agentes biológicos (Anti-TNF es la TB, y la incidencia de ésta se ha incrementado desde el advenimiento de la terapia biológica. Por tanto, la descripción de este caso no corresponde a un hecho médico aislado, sino a una problemática actual y real. Este es el primer caso que se reporta en la Costa Caribe.

  10. TNF-alpha neutralizing antibody blocks thermal sensitivity induced by compound 48/80-provoked mast cell degranulation [v2; ref status: indexed, http://f1000r.es/1w5

    Directory of Open Access Journals (Sweden)

    Devavani Chatterjea

    2013-09-01

    Full Text Available Background: Neuro-inflammatory circuits in the tissue regulate the complex pathophysiology of pain. Protective nociceptive pain serves as an early warning system against noxious environmental stimuli. Tissue-resident mast cells orchestrate the increased thermal sensitivity following injection of basic secretagogue compound 48/80 in the hind paw tissues of ND4 mice. Here we investigated the effects of pre-treatment with TNF-α neutralizing antibody on compound 48/80-provoked thermal hyperalgesia. Methods: We treated ND4 Swiss male mice with intravenous anti-TNF-α antibody or vehicle 30 minutes prior to bilateral, intra-plantar compound 48/80 administration and measured changes in the timing of hind paw withdrawal observed subsequent to mice being placed on a 51oC hotplate. We also assessed changes in tissue swelling, TNF-α gene expression and protein abundance, mast cell degranulation, and neutrophil influx in the hind paw tissue. Findings: We found that TNF-α neutralization significantly blocked thermal hyperalgesia, and reduced early tissue swelling. TNF-α neutralization had no significant effect on mast cell degranulation or neutrophil influx into the tissue, however. Moreover, no changes in TNF-α protein or mRNA levels were detected within 3 hours of administration of compound 48/80. Interpretation:  The neutralizing antibodies likely target pre-formed TNF-α including that stored in the granules of tissue-resident mast cells. Pre-formed TNF-α, released upon degranulation, has immediate effects on nociceptive signaling prior to the induction of neutrophil influx. These early effects on nociceptors are abrogated by TNF-α blockade, resulting in compromised nociceptive withdrawal responses to acute, harmful environmental stimuli.

  11. TNF-alpha neutralizing antibody blocks thermal sensitivity induced by compound 48/80-provoked mast cell degranulation [v1; ref status: indexed, http://f1000r.es/1mq

    Directory of Open Access Journals (Sweden)

    Devavani Chatterjea

    2013-08-01

    Full Text Available Background:  Neuro-inflammatory circuits in the tissue regulate the complex pathophysiology of pain.  Protective nociceptive pain serves as an early warning system against noxious environmental stimuli.  Tissue-resident mast cells orchestrate the increased thermal sensitivity following injection of basic secretagogue compound 48/80 in the hind paw tissues of ND4 mice.  Here we investigated the effects of pre-treatment with TNF-α neutralizing antibody on compound 48/80-provoked thermal hyperalgesia.  Methods:  We treated ND4 Swiss male mice with intravenous anti-TNF-α antibody or vehicle 30 minutes prior to bilateral, intra-plantar compound 48/80 administration and measured changes in the timing of hind paw withdrawal observed subsequent to mice being placed on a 51oC hotplate.  We also assessed changes in tissue swelling, TNF-α gene expression and protein abundance, mast cell degranulation, and neutrophil influx in the hind paw tissue.  Findings:  We found that TNF-α neutralization significantly blocked thermal hyperalgesia, and reduced early tissue swelling. TNF-α neutralization had no significant effect on mast cell degranulation or neutrophil influx into the tissue, however.  Moreover, no changes in TNF-α protein or mRNA levels were detected within 3 hours of administration of compound 48/80.  Interpretation:  The neutralizing antibodies likely target pre-formed TNF-α including that stored in the granules of tissue-resident mast cells. Pre-formed TNF-α, released upon degranulation, has immediate effects on nociceptive signaling prior to the induction of neutrophil influx.  These direct effects on nociceptors are abrogated by TNF-α blockade resulting in compromised nociceptive withdrawal responses to acute, harmful environmental stimuli.

  12. Hyperoxaluria Requires TNF Receptors to Initiate Crystal Adhesion and Kidney Stone Disease.

    Science.gov (United States)

    Mulay, Shrikant R; Eberhard, Jonathan N; Desai, Jyaysi; Marschner, Julian A; Kumar, Santhosh V R; Weidenbusch, Marc; Grigorescu, Melissa; Lech, Maciej; Eltrich, Nuru; Müller, Lisa; Hans, Wolfgang; Hrabě de Angelis, Martin; Vielhauer, Volker; Hoppe, Bernd; Asplin, John; Burzlaff, Nicolai; Herrmann, Martin; Evan, Andrew; Anders, Hans-Joachim

    2017-03-01

    Intrarenal crystals trigger inflammation and renal cell necroptosis, processes that involve TNF receptor (TNFR) signaling. Here, we tested the hypothesis that TNFRs also have a direct role in tubular crystal deposition and progression of hyperoxaluria-related CKD. Immunohistochemical analysis revealed upregulated tubular expression of TNFR1 and TNFR2 in human and murine kidneys with calcium oxalate (CaOx) nephrocalcinosis-related CKD compared with controls. Western blot and mRNA expression analyses in mice yielded consistent data. When fed an oxalate-rich diet, wild-type mice developed progressive CKD, whereas Tnfr1-, Tnfr2- , and Tnfr1/2- deficient mice did not. Despite identical levels of hyperoxaluria, Tnfr1-, Tnfr2- , and Tnfr1/2 -deficient mice also lacked the intrarenal CaOx deposition and tubular damage observed in wild-type mice. Inhibition of TNFR signaling prevented the induced expression of the crystal adhesion molecules, CD44 and annexin II, in tubular epithelial cells in vitro and in vivo , and treatment with the small molecule TNFR inhibitor R-7050 partially protected hyperoxaluric mice from nephrocalcinosis and CKD. We conclude that TNFR signaling is essential for CaOx crystal adhesion to the luminal membrane of renal tubules as a fundamental initiating mechanism of oxalate nephropathy. Furthermore, therapeutic blockade of TNFR might delay progressive forms of nephrocalcinosis in oxalate nephropathy, such as primary hyperoxaluria. Copyright © 2017 by the American Society of Nephrology.

  13. Influence of NKG2D Genetic Variants on Response to Anti-TNF Agents in Patients with Rheumatoid Arthritis

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    Milena Iwaszko

    2018-01-01

    Full Text Available A natural killer group 2 member D (NKG2D acts as a powerful activating and co-stimulatory receptor on immune effector cells including NK and T cells. Disruptions within the NKG2D signalling pathway may trigger an exacerbated immune response and promote autoimmune reactions. The objective of the study was to evaluate a plausible role of polymorphisms within the NKG2D gene as a predictor of how effective anti-tumor necrosis factor (TNF therapy is in rheumatoid arthritis (RA patients. A total of 280 RA patients receiving anti-TNF therapy were genotyped for NKG2D rs2255336 (A > G, rs1049174 (C > G, and rs1154831 (C > A. Clinical response was evaluated according to the European League against Rheumatism (EULAR criteria at the 12th and 24th week. Both the NKG2D rs225336 and rs1049174 polymorphisms were significantly associated with efficacy of TNF inhibitors. Inefficient therapy was more frequently observed in patients with rs2255336 GG or rs1049174 CC genotype as compared to other genotypes (p-value = 0.003 and p-value = 0.004, respectively. The presence of the rs2255336 G or the rs1049174 C allele correlated with a worse EULAR response (p-value = 0.002, p-value = 0.031, respectively. Moreover, patients carrying the rs2255336 or rs1049174 heterozygous genotype achieved better EULAR responses than patients with homozygous genotypes (p-value = 0.010 and p-value = 0.002, respectively. Data from the present study provides evidence that NKG2D polymorphisms may affect response to anti-TNF inhibitors in RA patients.

  14. Increased levels of circulating (TNF-α) is associated with (-308G/A) promoter polymorphism of TNF-α gene in Diabetic Nephropathy.

    Science.gov (United States)

    Umapathy, Dhamodharan; Krishnamoorthy, Ezhilarasi; Mariappanadar, Vairamani; Viswanathan, Vijay; Ramkumar, Kunka Mohanram

    2018-02-01

    The crucial role of Tumor Necrosis Factor-α (TNF-α) on renal function in patients with Diabetic Nephropathy (DN) has been well documented. The present study was designed to investigate the association of TNF-α [-308G/A, (rs1800629)] single nucleotide polymorphism (SNP) on the susceptibility to DN subjects and to correlate it with the plasma levels of TNF-α along with circulatory TNF-α receptor super family cytokines (sTNFR-1 and sTNFR-2). A total of 756 subjects, were recruited and divided into groups [Group-I, Control (n=218), Group-II, Normoalbuminuria (n=196), Group-IIIa, Microalbuminuria (n=178), Group-IIIb, Macroalbuminuria (n=164)] and were genotyped by PCR-restriction fragment length polymorphism (RFLP). Circulatory levels of TNF-α and sTNFR-1 & sTNFR-2 were measured using multiplex bead based assay. The 'A' allele of TNF-α (-308 G/A) SNP was associated with a significant risk for macroalbuminuria subjects (OR: 2.1; 95% CI: 0.8-3.7; PTNF-α, sTNF-R1 and sTNF-R2 from normo to macroalbuminuria subjects. In DN subjects, the TNF-α level was higher in individuals who had mutant AA, than the wild GG genotype of TNF-α gene. Our results conclude that rs1800629 polymorphism in TNF-α gene is associated with renal complications in T2DM subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. TNF-α Deficiency Prevents Renal Inflammation and Oxidative Stress in Obese Mice

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    Huaiguo Wang

    2017-07-01

    Full Text Available Background/Aims: Obese patients and experimental animals exhibit high levels of inflammatory cytokines, such as tumor necrosis factor (TNF-α. However, the role of TNF-α in the pathophysiologic process in obesity induced kidney damage is still unknown. Methods: We used TNF-α deficient mice and wild-type (WT C57/BJ6 mice controls to study the effect of TNF-α on inflammation and oxidative stress in kidney by the model of high-fat diet (HFD and primary isolated mouse renal proximal tubule cells treated with a mixture of free fatty acids (FFA. Results: Compared with the chow diet group, HFD-fed WT mice had higher urinary albumin and increased levels of renal fibrosis, glomerulosclerosis, inflammation, oxidative stress and apoptosis in the kidney. These changes were co-related with increased expression of TNF-α in the kidney and were attenuated by TNF-α deficiency. In vitro, accumulation of intracellular lipids induced TNF-α expression and oxidative stress in FFA treated primary proximal tubule cells. However, TNF-α inhibition with siRNA or TNF-α deficiency decreased the lipid induced oxidative stress in these cells. Conclusion: These findings suggest that TNF-α plays an important role in the HFD induced kidney damage, and targeting TNF-α and/or its receptors could be a promising therapeutic regimen for progressive nephropathy.

  16. TNF Receptor-2 Facilitates an Immunosuppressive Microenvironment in the Liver to Promote the Colonization and Growth of Hepatic Metastases

    DEFF Research Database (Denmark)

    Ham, Boram; Wang, Ni; D'Costa, Zarina

    2015-01-01

    Successful colonization by a cancer cell of a distant metastatic site requires immune escape in the new microenvironment. TNF signaling has been implicated broadly in the suppression of immune surveillance that prevents colonization at the metastatic site and therefore must be blocked...... chemotherapy-naïve colon cancer patients confirmed the presence of CD33(+)HLA-DR(-)TNFR2(+) myeloid cells in the periphery of hepatic metastases. Overall, our findings implicate TNFR2 in supporting MDSC-mediated immune suppression and metastasis in the liver, suggesting the use of TNFR2 inhibitors...... as a strategy to prevent metastatic progression to liver in colon, lung, and various other types of cancer....

  17. Primate TNF Promoters Reveal Markers of Phylogeny and Evolution of Innate Immunity

    Science.gov (United States)

    Baena, Andres; Ligeiro, Filipa; Diop, Ousmane M.; Brieva, Claudia; Gagneux, Pascal; O'Brien, Stephen J.; Ryder, Oliver A.; Goldfeld, Anne E.

    2007-01-01

    Background Tumor necrosis factor (TNF) is a critical cytokine in the immune response whose transcriptional activation is controlled by a proximal promoter region that is highly conserved in mammals and, in particular, primates. Specific single nucleotide polymorphisms (SNPs) upstream of the proximal human TNF promoter have been identified, which are markers of human ancestry. Methodology/Principal findings Using a comparative genomics approach we show that certain fixed genetic differences in the TNF promoter serve as markers of primate speciation. We also demonstrate that distinct alleles of most human TNF promoter SNPs are identical to fixed nucleotides in primate TNF promoters. Furthermore, we identify fixed genetic differences within the proximal TNF promoters of Asian apes that do not occur in African ape or human TNF promoters. Strikingly, protein-DNA binding assays and gene reporter assays comparing these Asian ape TNF promoters to African ape and human TNF promoters demonstrate that, unlike the fixed differences that we define that are associated with primate phylogeny, these Asian ape-specific fixed differences impair transcription factor binding at an Sp1 site and decrease TNF transcription induced by bacterial stimulation of macrophages. Conclusions/significance Here, we have presented the broadest interspecies comparison of a regulatory region of an innate immune response gene to date. We have characterized nucleotide positions in Asian ape TNF promoters that underlie functional changes in cell type- and stimulus-specific activation of the TNF gene. We have also identified ancestral TNF promoter nucleotide states in the primate lineage that correspond to human SNP alleles. These findings may reflect evolution of Asian and African apes under a distinct set of infectious disease pressures involving the innate immune response and TNF. PMID:17637837

  18. [Cellular adhesion signal transduction network of tumor necrosis factor-alpha induced hepatocellular carcinoma cells].

    Science.gov (United States)

    Zheng, Yongchang; Du, Shunda; Xu, Haifeng; Xu, Yiyao; Zhao, Haitao; Chi, Tianyi; Lu, Xin; Sang, Xinting; Mao, Yilei

    2014-11-18

    To systemically explore the cellular adhesion signal transduction network of tumor necrosis factor-alpha (TNF-α)-induced hepatocellular carcinoma cells with bioinformatics tools. Published microarray dataset of TNF-α-induced HepG2, human transcription factor database HTRI and human protein-protein interaction database HPRD were used to construct and analyze the signal transduction network. In the signal transduction network, MYC and SP1 were the key nodes of signaling transduction. Several genes from the network were closely related with cellular adhesion.Epidermal growth factor receptor (EGFR) is a possible key gene of effectively regulating cellular adhesion during the induction of TNF-α. EGFR is a possible key gene for TNF-α-induced metastasis of hepatocellular carcinoma.

  19. Linear ubiquitination signals in adaptive immune responses.

    Science.gov (United States)

    Ikeda, Fumiyo

    2015-07-01

    Ubiquitin can form eight different linkage types of chains using the intrinsic Met 1 residue or one of the seven intrinsic Lys residues. Each linkage type of ubiquitin chain has a distinct three-dimensional topology, functioning as a tag to attract specific signaling molecules, which are so-called ubiquitin readers, and regulates various biological functions. Ubiquitin chains linked via Met 1 in a head-to-tail manner are called linear ubiquitin chains. Linear ubiquitination plays an important role in the regulation of cellular signaling, including the best-characterized tumor necrosis factor (TNF)-induced canonical nuclear factor-κB (NF-κB) pathway. Linear ubiquitin chains are specifically generated by an E3 ligase complex called the linear ubiquitin chain assembly complex (LUBAC) and hydrolyzed by a deubiquitinase (DUB) called ovarian tumor (OTU) DUB with linear linkage specificity (OTULIN). LUBAC linearly ubiquitinates critical molecules in the TNF pathway, such as NEMO and RIPK1. The linear ubiquitin chains are then recognized by the ubiquitin readers, including NEMO, which control the TNF pathway. Accumulating evidence indicates an importance of the LUBAC complex in the regulation of apoptosis, development, and inflammation in mice. In this article, I focus on the role of linear ubiquitin chains in adaptive immune responses with an emphasis on the TNF-induced signaling pathways. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Increased TNF-alpha/IFN-gamma/IL-2 and decreased TNF-alpha/IFN-gamma production by central memory T cells are associated with protective responses against bovine tuberculosis following BCG vaccination

    Directory of Open Access Journals (Sweden)

    Mayara Fernanda Maggioli

    2016-10-01

    Full Text Available Central memory T cells (Tcm and polyfunctional CD4 T cell responses contribute to vaccine-elicited protection with both human and bovine tuberculosis (TB; however, their combined role in protective immunity to TB is unclear. To address this question, we evaluated polyfunctional cytokine responses by CD4 T cell effector / memory populations from bacille Calmette Guerin (BCG vaccinated and non-vaccinated calves prior to and after aerosol challenge with virulent Mycobacterium bovis. Polyfunctional cytokine expression patterns in the response by Tcm, effector memory, and effector T cell subsets were similar between BCG-vaccinated and M. bovis-infected calves; only differing in magnitude (i.e., infected > vaccinated. BCG vaccination, however, did alter the kinetics of the ensuing response to virulent M. bovis infection. Early after challenge (three weeks post-infection, non-vaccinates had greater antigen-specific IFN-γ/TNF-α and lesser IFN-γ/TNF-α/IL-2 responses by Tcm cells than did vaccinated animals. Importantly, these differences were also associated with mycobacterial burden upon necropsy. Polyfunctional responses to ESAT-6:CFP10 (antigens not synthesized by BCG strains were detected in memory subsets, as well as in effector cells, as early as three weeks after challenge. These findings suggest that cell fate divergence may occur early after antigen priming in the response to bovine TB and that memory and effector T cells may expand concurrently during the initial phase of the immune response. In summary, robust IFN-γ/TNF-α response by Tcm cells is associated with greater mycobacterial burden while IFN-γ/TNF-α/IL-2 response by Tcm cells are indicative of a protective response to bovine TB.

  1. Direct bone formation during distraction osteogenesis does not require TNF alpha receptors and elevated serum TNF alpha fails to inhibit bone formation in TNFR1 deficient mice

    Science.gov (United States)

    Distraction osteogenesis (DO) is a process which induces direct new bone formation as a result of mechanical distraction. Tumor necrosis factor-alpha (TNF) is a cytokine that can modulate osteoblastogenesis. The direct effects of TNF on direct bone formation in rodents are hypothetically mediated th...

  2. TNF receptor 1, IL-1 receptor, and iNOS genetic knockout mice are not protected from anthrax infection.

    Science.gov (United States)

    Kalns, John; Scruggs, Julie; Millenbaugh, Nancy; Vivekananda, Jeeva; Shealy, David; Eggers, Jeffrey; Kiel, Johnathan

    2002-03-22

    Anthrax produces at least two toxins that cause an intense systemic inflammatory response, edema, shock, and eventually death. The relative contributions of various elements of the immune response to mortality and course of disease progression are poorly understood. We hypothesized that knockout mice missing components of the immune system will have an altered response to infection. Parent strain mice and knockouts were challenged with LD95 of anthrax spores (5 x 10(6)) administered subcutaneously. Our results show that all genetic knockouts succumbed to anthrax infection at the same frequency as the parent. TNF antibody delayed death but TNF receptor 1 knockout had no effect. IL-1 receptor or iNOS knockouts died sooner. Anthrax was more abundant in the injection site of TNF-alpha and iNOS knockouts compared to parent suggesting that attenuated cellular response increases rate of disease progression. With the exception of edema and necrosis at the injection site pathological changes in internal organs were not observed. (C)2002 Elsevier Science (USA).

  3. TNF-α Blocker Effect of Naringenin-Loaded Sericin Microparticles that Are Potentially Useful in the Treatment of Psoriasis

    Directory of Open Access Journals (Sweden)

    Theodora Chlapanidas

    2014-08-01

    Full Text Available This study aims to evaluate the effect of combined use of the racemic flavanone Naringenin (NRG and the protein sericin as TNF-α blockers. Sericin (SMs and (R/S NRG-loaded Sericin (SNRGMs microparticles were prepared by spray-drying, characterized in terms of morphology and particle size distribution, and encapsulation efficiency was determined. Concerning morphology and particle size distribution of microparticles, results indicated that they were not affected by the presence of NRG. The encapsulation efficiency was almost quantitative (93%, thus proving that sericin can be advantageously loaded with (R/S NRG. Biological evaluation of (R/S NRG, SMs and SNRGMs was then performed in lipopolysaccharide (LPS-stimulated human peripheral blood mononuclear cells (hPBMC. SNRGMs resulted cytotoxic at the higher dose used (200 μg/mL and the effect was greater than (R/S NRG alone. Moreover, even if sericin alone was not effective in suppressing LPS-induced serum TNF-α levels, SNRGMs loaded with 9.3% of (R/S NRG were significantly more potent than (R/S NRG alone. In summary, this study provides the proof of concept that sericin-based microspheres loaded with TNF-α-blockers could contribute to the down regulation of the cytokine and represents the starting point for the development of new topical formulations for the treatment of middle-stage psoriasis.

  4. TNF-α blocker effect of nari