scholarly journals Involvement of diacylglycerol production in activation of nuclear factor κB by a CD14-mediated lipopolysaccharide stimulus

1997 ◽  
Vol 325 (1) ◽  
pp. 223-228 ◽  
Author(s):  
Hisanori YAMAMOTO ◽  
Kentaro HANADA ◽  
Masahiro NISHIJIMA
Keyword(s):  
Phospholipase C ◽  
Phospholipase D ◽  
Nuclear Translocation ◽  
Chinese Hamster ◽  
Nuclear Factor Κb ◽  
Short Chain ◽  
Nuclear Factor ◽  
Mouse Macrophage

Exposure of Chinese hamster CHO-K1 transfectant cells expressing mouse CD14 (CHO/CD14 cells) to lipopolysaccharide (LPS) induced rapid elevation of the cellular diacylglycerol (DAG) and choline/phosphocholine levels and nuclear translocation of nuclear factor κB (NFκB). When cells were incubated with short-chain DAG analogues or bacterial phospholipase C, NFκB activation occurred even without the LPS stimulus. Treatment of CHO/CD14 cells with tricyclo[5.2.1.02.6]decyl-(9[8])xanthogenate (D609), an inhibitor of phosphatidylcholine-specific phospholipase C and phospholipase D, almost completely inhibited not only the LPS-dependent production of DAG and choline/phosphocholine but also the LPS-dependent NFκB activation. In contrast, treatment of cells with 1-(6-{[3-methoxyoestra-1,3,5(10)-trien-17β-yl]-1H-pyrrole-2,5-dione (U73122), an inhibitor of phosphatidylinositol-specific phospholipase C in vitro, did not affect the LPS-dependent activation of NFκB. Production of DAG and activation of NFκB after the LPS stimulus were observed in mouse macrophage-like J774.1 cells, and this response to LPS by J774.1 cells was also inhibited by D609. These results suggest that the production of DAG from phosphatidylcholine was upstream of NFκB activation in response to a CD14-mediated LPS stimulus.

scholarly journals Cell-specific Activation of Nuclear Factor-κB by the ParasiteTrypanosoma cruziPromotes Resistance to Intracellular Infection

2000 ◽  
Vol 11 (1) ◽  
pp. 153-160 ◽  
Author(s):  
Belinda S. Hall ◽  
Winnie Tam ◽  
Ranjan Sen ◽  
Miercio E. A. Pereira
Keyword(s):  
Mammalian Cells ◽  
Nuclear Translocation ◽  
Nuclear Factor Κb ◽  
Microbial Pathogens ◽  
Tissue Tropism ◽  
Nuclear Factor ◽  
Infection Level ◽  
Direct Role ◽  
Intracellular Infection

The transcription factor nuclear factor-κB (NF-κB) is central to the innate and acquired immune response to microbial pathogens, coordinating cellular responses to the presence of infection. Here we demonstrate a direct role for NF-κB activation in controlling intracellular infection in nonimmune cells. Trypanosoma cruzi is an intracellular parasite of mammalian cells with a marked preference for infection of myocytes. The molecular basis for this tissue tropism is unknown. Trypomastigotes, the infectious stage of T. cruzi, activate nuclear translocation and DNA binding of NF-κB p65 subunit and NF-κB-dependent gene expression in epithelial cells, endothelial cells, and fibroblasts. Inactivation of epithelial cell NF-κB signaling by inducible expression of the inhibitory mutant IκBaM significantly enhances parasite invasion.T. cruzi do not activate NF-κB in cells derived from skeletal, smooth, or cardiac muscle, despite the ability of these cells to respond to tumor necrosis factor-α with NF-κB activation. The in vitro infection level in these muscle-derived cells is more than double that seen in the other cell types tested. Therefore, the ability of T. cruzi to activate NF-κB correlates inversely with susceptibility to infection, suggesting that NF-κB activation is a determinant of the intracellular survival and tissue tropism ofT. cruzi.

Testes-specific protease 50 (TSP50) promotes cell proliferation through the activation of the nuclear factor κB (NF-κB) signalling pathway

2011 ◽  
Vol 436 (2) ◽  
pp. 457-467 ◽  
Author(s):  
Zhen-Bo Song ◽  
Yong-Li Bao ◽  
Yu Zhang ◽  
Xu-Guang Mi ◽  
Ping Wu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Colony Formation ◽  
Nuclear Translocation ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Nuclear Factor Κb ◽  
Signalling Pathway ◽  
Nuclear Factor ◽  
Iκb Kinase ◽  
Specific Protease

TSP50 (testes-specific protease 50) is a testis-specific expression protein, which is expressed abnormally at high levels in breast cancer tissues. This makes it an attractive molecular marker and a potential target for diagnosis and therapy; however, the biological function of TSP50 is still unclear. In the present study, we show that overexpression of TSP50 in CHO (Chinese-hamster ovary) cells markedly increased cell proliferation and colony formation. Mechanistic studies have revealed that TSP50 can enhance the level of TNFα (tumour necrosis factor α)- and PMA-induced NF-κB (nuclear factor κB)-responsive reporter activity, IκB (inhibitor of NF-κB) α degradation and p65 nuclear translocation. In addition, the knockdown of endogenous TSP50 in MDA-MB-231 cells greatly inhibited NF-κB activity. Co-immunoprecipitation studies demonstrated an interaction of TSP50 with the NF-κB–IκBα complex, but not with the IKK (IκB kinase) α/β–IKKγ complex, which suggested that TSP50, as a novel type of protease, promoted the degradation of IκBα proteins by binding to the NF-κB–IκBα complex. Our results also revealed that TSP50 can enhance the expression of NF-κB target genes involved in cell proliferation. Furthermore, overexpression of a dominant-negative IκB mutant that is resistant to proteasome-mediated degradation significantly reversed TSP50-induced cell proliferation, colony formation and tumour formation in nude mice. Taken together, the results of the present study suggest that TSP50 promotes cell proliferation, at least partially, through activation of the NF-κB signalling pathway.

scholarly journals Dehydroxymethylepoxyquinomicin, a Novel Nuclear Factor-κB Inhibitor, Enhances Antitumor Activity of Taxanes in Anaplastic Thyroid Cancer Cells

Endocrinology ◽  
2008 ◽  
Vol 149 (11) ◽  
pp. 5357-5365 ◽  
Author(s):  
Zhaowei Meng ◽  
Norisato Mitsutake ◽  
Masahiro Nakashima ◽  
Dmytro Starenki ◽  
Michiko Matsuse ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Nuclear Translocation ◽  
Combined Treatment ◽  
Xenograft Model ◽  
Anaplastic Thyroid Cancer ◽  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Antitumor Activities

Nuclear factor κB (NF-κB), as an antiapoptotic factor, crucially affects the outcomes of cancer treatments, being one of the major culprits of resistance to chemotherapy. In this study, we investigated whether dehydroxymethylepoxyquinomicin (DHMEQ), a novel NF-κB inhibitor, can enhance antitumor activities of taxanes in anaplastic thyroid cancer (ATC) cells. Taxanes induced NF-κB activation in ATC cells, which could compromise the therapeutic effect of the drugs. However, DHMEQ, by inhibiting the nuclear translocation of NF-κB, completely suppressed the DNA binding capacities of NF-κB and lowered the levels of nuclear NF-κB protein. Compared with single treatment (either taxane or DHMEQ), the combined treatment strongly potentiated apoptosis, confirmed by cell survival assay; Western blotting for poly (ADP-ribose) polymerase, caspase 3, X-linked inhibitor of apoptosis, and survivin; and flow cytometry for annexin V. Furthermore, we also demonstrate for the first time that the combined treatment showed significantly greater inhibitory effect on tumor growth in a nude mice xenograft model. These findings suggest that taxanes are able to induce NF-κB activation in ATC cells, which could attenuate antitumor activities of the drugs, but inhibition of NF-κB by DHMEQ creates a chemosensitive environment and greatly enhances apoptosis in taxanes-treated ATC cells in vitro and in vivo. Thus, DHMEQ may emerge as an attractive therapeutic strategy to enhance the response to taxanes in ATCs.

scholarly journals A Nitrobenzoyl Sesquiterpenoid Insulicolide A Prevents Osteoclast Formation via Suppressing c-Fos-NFATc1 Signaling Pathway

2022 ◽  
Vol 12 ◽  
Author(s):  
Yanhui Tan ◽  
Minhong Ke ◽  
Zhichao Li ◽  
Yan Chen ◽  
Jiehuang Zheng ◽  
...  
Keyword(s):  
Nuclear Translocation ◽  
Osteoclast Differentiation ◽  
Nuclear Factor Κb ◽  
Osteoclast Formation ◽  
Marine Fungus ◽  
Nuclear Factor ◽  
Protective Effects ◽  
Mice Model

It is a viable strategy to inhibit osteoclast differentiation for the treatment of osteolytic diseases such as osteoporosis, rheumatoid arthritis and tumor bone metastases. Here we assessed the effects of insulicolide A, a natural nitrobenzoyl sesquiterpenoid derived from marine fungus, on receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis in vitro and its protective effects on LPS-induced osteolysis mice model in vivo. The results demonstrated that insulicolide A inhibited osteoclastogenesis from 1 μM in vitro. Insulicolide A could prevent c-Fos and nuclear factor of activated T-cell cytoplasmic 1 (NFATc1) nuclear translocation and attenuate the expression levels of osteoclast-related genes and DC-STAMP during RANKL-stimulated osteoclastogenesis but have no effects on NF-κB and MAPKs. Insulicolide A can also protect the mice from LPS-induced osteolysis. Our research provides the first evidence that insulicolide A may inhibit osteoclastogenesis both in vitro and in vivo, and indicates that it may have potential for the treatment of osteoclast-related diseases.

scholarly journals The Protective Roles and Molecular Mechanisms of Troxerutin (Vitamin P4) for the Treatment of Chronic Diseases: A Mechanistic Review

2020 ◽  
Vol 19 (1) ◽  
pp. 97-110
Author(s):  
Mohammad Zamanian ◽  
Gholamreza Bazmandegan ◽  
Antoni Sureda ◽  
Eduardo Sobarzo-Sanchez ◽  
Hasan Yousefi-Manesh ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Nuclear Translocation ◽  
Therapeutic Potential ◽  
Acetylcholinesterase Activity ◽  
Nuclear Factor Κb ◽  
In Vivo Studies ◽  
Related Factor ◽  
Nuclear Factor

: Troxerutin (TRX), a semi-synthetic bioflavonoid derived from rutin, has been reported to exert several pharmacological effects including antioxidant, anti-inflammatory, antihyperlipidemic, and nephroprotective. However, the related molecular details and its mechanisms remain poorly understood. In the present review, we presented evidences from the diversity in vitro and in vivo studies on the therapeutic potential of TRX against neurodegenerative, diabetes, cancer and cardiovascular diseases with the purpose to find molecular pathways related to the treatment efficacy. TRX has a beneficial role in many diseases through multiple mechanisms including, increasing antioxidant enzymes and reducing oxidative damage, decreasing in proapoptotic proteins (APAF-1, BAX, caspases-9 and-3) and increasing the antiapoptotic BCL-2, increasing the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and downregulating the nuclear factor κB (NFκ). TRX also reduces acetylcholinesterase activity and upregulates phosphoinositide 3- kinase/Akt signaling pathway in Alzheimer’s disease models. Natural products such as TRX may develop numerous and intracellular pathways at several steps in the treatment of many diseases. Molecular mechanisms of action are revealing novel, possible combinational beneficial approaches to treat multiple pathological conditions.

scholarly journals Thyroid-Stimulating Hormone Induces Interleukin-6 Release from Human Adipocytes through Activation of the Nuclear Factor-κB Pathway

Endocrinology ◽  
2008 ◽  
Vol 149 (6) ◽  
pp. 3062-3066 ◽  
Author(s):  
Tayze T. Antunes ◽  
AnneMarie Gagnon ◽  
Melanie L. Langille ◽  
Alexander Sorisky
Keyword(s):  
Nuclear Translocation ◽  
Chinese Hamster ◽  
Fold Increase ◽  
Nuclear Factor Κb ◽  
Thyroid Stimulating Hormone ◽  
Nuclear Factor ◽  
Human Adipocytes ◽  
Ovarian Cells ◽  
Iκb Kinase ◽  
Iκbα Degradation

Our objective was to identify the signaling pathway activated by TSH that induces IL-6 secretion from human abdominal sc differentiated adipocytes. Human abdominal sc preadipocytes in culture were differentiated into adipocytes. IL-6 release stimulated by TSH was inhibited by 35% (P < 0.05) with SN50, an inhibitor of nuclear factor-κB (NF-κB) nuclear translocation, and 60% (P < 0.01) with sc-514, an inhibitor of inhibitory-κB (IκB) kinase (IKK)-β. Phosphorylation of IKKβ increased upon TSH treatment (10.3-fold, P < 0.01), and IκBα levels were reduced by 78% (P < 0.01). TSH activated NF-κB (23-fold, P < 0.001), a process that was inhibited (60%, P < 0.01) by SN50. Inhibition of protein kinase A by H89 did not affect TSH-stimulated IKKβ phosphorylation or IκBα degradation. TSH-mediated NF-κB activation and IL-6 induction also specifically occurred in Chinese hamster ovarian cells expressing the human TSH receptor, resulting in a 5.9-fold (P < 0.001) increase in IKKβ phosphorylation and a 9.5-fold increase in IL-6 mRNA expression. Our data demonstrate that the IKKβ/NF-κB pathway is a novel TSH target that is required for TSH-induced IL-6 release from human adipocytes.

scholarly journals Periprosthetic Osteolysis: Mechanisms, Prevention and Treatment

2019 ◽  
Vol 8 (12) ◽  
pp. 2091 ◽  
Author(s):  
Stuart B. Goodman ◽  
Jiri Gallo
Keyword(s):  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Activator Protein 1 ◽  
Periprosthetic Osteolysis ◽  
Bone Implant ◽  
Joint Replacements ◽  
In Vivo Experiments ◽  
Mechanical Factors

Clinical studies, as well as in vitro and in vivo experiments have demonstrated that byproducts from joint replacements induce an inflammatory reaction that can result in periprosthetic osteolysis (PPOL) and aseptic loosening (AL). Particle-stimulated macrophages and other cells release cytokines, chemokines, and other pro-inflammatory substances that perpetuate chronic inflammation, induce osteoclastic bone resorption and suppress bone formation. Differentiation, maturation, activation, and survival of osteoclasts at the bone–implant interface are under the control of the receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent pathways, and the transcription factors like nuclear factor κB (NF-κB) and activator protein-1 (AP-1). Mechanical factors such as prosthetic micromotion and oscillations in fluid pressures also contribute to PPOL. The treatment for progressive PPOL is only surgical. In order to mitigate ongoing loss of host bone, a number of non-operative approaches have been proposed. However, except for the use of bisphosphonates in selected cases, none are evidence based. To date, the most successful and effective approach to preventing PPOL is usage of wear-resistant bearing couples in combination with advanced implant designs, reducing the load of metallic and polymer particles. These innovations have significantly decreased the revision rate due to AL and PPOL in the last decade.

scholarly journals The nuclear factor κB inhibitor (E)-2-fluoro-4′-methoxystilbene inhibits firefly luciferase

2012 ◽  
Vol 32 (6) ◽  
pp. 531-537 ◽  
Author(s):  
Albert Braeuning ◽  
Silvia Vetter
Keyword(s):  
Photon Emission ◽  
Gene Promoter ◽  
Firefly Luciferase ◽  
Nuclear Factor Κb ◽  
Signalling Pathway ◽  
Luciferase Reporter ◽  
Nuclear Factor ◽  
Reporter System ◽  
Reporter Assays

Photinus pyralis (firefly) luciferase is widely used as a reporter system to monitor alterations in gene promoter and/or signalling pathway activities in vitro. The enzyme catalyses the formation of oxyluciferin from D-luciferin in an ATP-consuming reaction involving photon emission. The purpose of the present study was to characterize the luciferase-inhibiting potential of (E)-2-fluoro-4′-methoxystilbene, which is known as a potent inhibitor of the NF-κB (nuclear factor κB) signalling pathway that is used to modulate the NF-κB signalling pathway in vitro. Results show that (E)-2-fluoro-4′-methoxystilbene effectively inhibits firefly luciferase activity in cell lysates and living cells in a non-competitive manner with respect to the luciferase substrates D-luciferin and ATP. By contrast, the compound has no effect on Renilla and Gaussia luciferases. The mechanism of firefly luciferase inhibition by (E)-2-fluoro-4′-methoxystilbene, as well as its potency is comparable to its structure analogue resveratrol. The in vitro use of trans-stilbenes such as (E)-2-fluoro-4′-methoxystilbene or resveratrol compromises firefly luciferase reporter assays as well as ATP/luciferase-based cell viability assays.

In Vitro and in Vivo Nuclear Factor-κB Inhibitory Effects of the Cell-Penetrating Penetratin Peptide

2006 ◽  
Vol 69 (6) ◽  
pp. 2027-2036 ◽  
Author(s):  
Tamás Letoha ◽  
Erzsébet Kusz ◽  
Gábor Pápai ◽  
Annamária Szabolcs ◽  
József Kaszaki ◽  
...  
Keyword(s):  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Inhibitory Effects ◽  
Cell Penetrating

scholarly journals Activation of Nuclear Factor κb and bcl-x Survival Gene Expression by Nerve Growth Factor Requires Tyrosine Phosphorylation of IκBα

2001 ◽  
Vol 152 (4) ◽  
pp. 753-764 ◽  
Author(s):  
Nguyen Truc Bui ◽  
Antonia Livolsi ◽  
Jean-Francois Peyron ◽  
Jochen H.M. Prehn
Keyword(s):  
Gene Expression ◽  
Tyrosine Phosphorylation ◽  
Fluorescent Protein ◽  
Nuclear Translocation ◽  
Nuclear Factor Κb ◽  
Dominant Negative ◽  
Dominant Negative Mutant ◽  
Nuclear Factor ◽  
Human Neuroblastoma ◽  
Tnf Α

NGF has been shown to support neuron survival by activating the transcription factor nuclear factor-κB (NFκB). We investigated the effect of NGF on the expression of Bcl-xL, an anti–apoptotic Bcl-2 family protein. Treatment of rat pheochromocytoma PC12 cells, human neuroblastoma SH-SY5Y cells, or primary rat hippocampal neurons with NGF (0.1–10 ng/ml) increased the expression of bcl-xL mRNA and protein. Reporter gene analysis revealed a significant increase in NFκB activity after treatment with NGF that was associated with increased nuclear translocation of the active NFκB p65 subunit. NGF-induced NFκB activity and Bcl-xL expression were inhibited in cells overexpressing the NFκB inhibitor, IκBα. Unlike tumor necrosis factor-α (TNF-α), however, NGF-induced NFκB activation occurred without significant degradation of IκBs determined by Western blot analysis and time-lapse imaging of neurons expressing green fluorescent protein–tagged IκBα. Moreover, in contrast to TNF-α, NGF failed to phosphorylate IκBα at serine residue 32, but instead caused significant tyrosine phosphorylation. Overexpression of a Y42F mutant of IκBα potently suppressed NFG-, but not TNF-α–induced NFκB activation. Conversely, overexpression of a dominant negative mutant of TNF receptor-associated factor-6 blocked TNF-α–, but not NGF-induced NFκB activation. We conclude that NGF and TNF-α induce different signaling pathways in neurons to activate NFκB and bcl-x gene expression.

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