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.

scholarly journals An Ebola Virus-Like Particle-Based Reporter System Enables Evaluation of Antiviral DrugsIn Vivounder Non-Biosafety Level 4 Conditions

2016 ◽  
Vol 90 (19) ◽  
pp. 8720-8728 ◽  
Author(s):  
Dapeng Li ◽  
Tan Chen ◽  
Yang Hu ◽  
Yu Zhou ◽  
Qingwei Liu ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Viral Entry ◽  
Ebola Virus ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Target Cells ◽  
Reporter System ◽  
Biosafety Level

ABSTRACTEbola virus (EBOV) is a highly contagious lethal pathogen. As a biosafety level 4 (BSL-4) agent, however, EBOV is restricted to costly BSL-4 laboratories for experimentation, thus significantly impeding the evaluation of EBOV vaccines and drugs. Here, we report an EBOV-like particle (EBOVLP)-based luciferase reporter system that enables the evaluation of anti-EBOV agentsin vitroandin vivooutside BSL-4 facilities. Cotransfection of HEK293T cells with four plasmids encoding the proteins VP40, NP, and GP of EBOV and firefly luciferase (Fluc) resulted in the production of Fluc-containing filamentous particles that morphologically resemble authentic EBOV. The reporter EBOVLP was capable of delivering Fluc into various cultured cells in a GP-dependent manner and was recognized by a conformation-dependent anti-EBOV monoclonal antibody (MAb). Significantly, inoculation of mice with the reporter EBOVLP led to the delivery of Fluc protein into target cells and rapid generation of intense bioluminescence signals that could be blocked by the administration of EBOV neutralizing MAbs. This BSL-4-free reporter system should facilitate high-throughput screening for anti-EBOV drugs targeting viral entry and efficacy testing of candidate vaccines.IMPORTANCEEbola virus (EBOV) researches have been limited to costly biosafety level 4 (BSL-4) facilities due to the lack of animal models independent of BSL-4 laboratories. In this study, we reveal that a firefly luciferase-bearing EBOV-like particle (EBOVLP) with typical filamentous EBOV morphology is capable of delivering the reporter protein into murine target cells bothin vitroandin vivo. Moreover, we demonstrate that the reporter delivery can be inhibited bothin vitroandin vivoby a known anti-EBOV protective monoclonal antibody, 13C6. Our work provides a BSL-4-free system that can facilitate thein vivoevaluation of anti-EBOV antibodies, drugs, and vaccines. The system may also be useful for mechanistic study of the viral entry process.

scholarly journals Real-Time Monitoring of Nuclear Factor κB Activity in Cultured Cells and in Animal Models

2009 ◽  
Vol 8 (5) ◽  
pp. 7290.2009.00026 ◽  
Author(s):  
Christian E. Badr ◽  
Johanna M. Niers ◽  
Lee-Ann Tjon-Kon-Fat ◽  
David P. Noske ◽  
Thomas Wurdinger ◽  
...  
Keyword(s):  
Real Time ◽  
Cultured Cells ◽  
Tumor Development ◽  
Nuclear Factor Κb ◽  
Tumor Formation ◽  
Nuclear Factor ◽  
Reporter System ◽  
Human Disorders

Nuclear factor κB (NF-κB) is a transcription factor that plays a major role in many human disorders, including immune diseases and cancer. We designed a reporter system based on NF-κB responsive promoter elements driving expression of the secreted Gaussia princeps luciferase (Gluc). We show that this bioluminescent reporter is a highly sensitive tool for noninvasive monitoring of the kinetics of NF-κB activation and inhibition over time, both in conditioned medium of cultured cells and in the blood and urine of animals. NF-κB activation was successfully monitored in real time in endothelial cells in response to tumor angiogenic signaling, as well as in monocytes in response to inflammation. Further, we demonstrated dual blood monitoring of both NF-κB activation during tumor development as correlated to tumor formation using the NF-κB Gluc reporter, as well as the secreted alkaline phosphatase reporter. This NF-κB reporter system provides a powerful tool for monitoring NF-κB activity in real time in vitro and in vivo.

A mechanism for the suppression of interleukin-1-induced nuclear factor κB activation by protein phosphatase 2Cη-2

2009 ◽  
Vol 423 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Takeaki Henmi ◽  
Kazutaka Amano ◽  
Yuko Nagaura ◽  
Kunihiro Matsumoto ◽  
Seishi Echigo ◽  
...  
Keyword(s):  
Transforming Growth Factor ◽  
Interleukin 1 ◽  
Ectopic Expression ◽  
Transforming Growth Factor Β ◽  
Nuclear Factor Κb ◽  
Signalling Pathway ◽  
Nuclear Factor ◽  
Interfering Rna ◽  
Signalling Cascade

IL-1 (interleukin-1) is a pro-inflammatory cytokine that has a variety of effects during the process of inflammation. Stimulating cells with IL-1 initiates a signalling cascade that includes the activation of NF-κB (nuclear factor κB), and subsequently induces a variety of inflammatory genes. Although the molecular mechanism for the IL-1-induced activation of NF-κB has been well documented, much less is known about the mechanism by which protein phosphatases down-regulate this pathway. Here we show that mouse PP2Cη-2 (protein serine/threonine phosphatase 2Cη-2), a novel member of the protein serine/threonine phosphatase 2C family, inhibits the IL-1–NF-κB signalling pathway. Ectopic expression of PP2Cη-2 in human embryonic kidney HEK293IL-1RI cells inhibited the IL-1-induced activation of NF-κB. TAK1 (transforming-growth-factor-β-activated kinase 1) mediates the IL-1 signalling pathway to NF-κB, and we observed that the TAK1-induced activation of NF-κB was suppressed by PP2Cη-2 expression. Expression of IKKβ [IκB (inhibitory κB) kinase β], which lies downstream of TAK1, activates NF-κB, and this activation was also readily reversed by PP2Cη-2 co-expression. Additionally, PP2Cη-2 knockdown with small interfering RNA further stimulated the IL-1-enhanced phosphorylation of IKKβ and destabilization of IκBα in HeLa cells. PP2Cη-2 knockdown also increased the IL-1-induced expression of IL-6 mRNA. Furthermore, IKKβ was readily dephosphorylated by PP2Cη-2 in vitro. These results suggest that PP2Cη-2 inhibits the IL-1–NF-κB signalling pathway by selectively dephosphorylating IKKβ.

scholarly journals Inflammatory Cytokines Regulate Glycoprotein Subunit β5 of Thyrostimulin through Nuclear Factor-κB

Endocrinology ◽  
2008 ◽  
Vol 150 (5) ◽  
pp. 2237-2243 ◽  
Author(s):  
Chizuko Suzuki ◽  
Hiroshi Nagasaki ◽  
Yoshiki Okajima ◽  
Hidetaka Suga ◽  
Nobuaki Ozaki ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Nuclear Factor Κb ◽  
Luciferase Reporter ◽  
Nuclear Factor ◽  
Glycoprotein Hormone ◽  
Human Pituitary ◽  
Binding Motifs ◽  
Reporter Assays ◽  
Flanking Region ◽  
Thyrotropic Activity

Thyrostimulin is a heterodimeric hormone comprised of two glycoprotein hormone subunits, namely glycoprotein hormone subunit α2 and glycoprotein hormone subunit β5 (GPB5). Immunological studies have revealed that both subunits colocalize in human pituitary corticotroph cells. Although recombinant thyrostimulin protein selectively activates the TSH receptor and has thyrotropic activity in rats, its biological functions have not been clarified. To explore the physiological regulators for the GPB5, the 5′-flanking region of the GPB5 coding sequence up to 3-kb upstream was analyzed by luciferase reporter assays. We found that nuclear factor-κB (NF-κB) markedly activated GPB5 transcription. Disruption of the putative NF-κB-binding motifs in the GPB5 5′-flanking region silenced the GPB5 activation by p65. Chromatin immunoprecipitation assays revealed that recombinant p65 bound to the predicted NF-κB-binding sites. Because NF-κB is known to associate with acute phase inflammatory cytokines, we examined whether TNFα or IL-1β could regulate GPB5. Both these cytokines activated GPB5 transcription by 2- to 3-fold, and their effects were abolished by the addition of MG132, a NF-κB inhibitor. Our results suggest that inflammatory cytokines positively regulate thyrostimulin through NF-κB activation.

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.

Detection and Functional Evaluation of −262A/T and −188A/G Polymorphisms of SLAM Gene in Patients with Systemic Lupus Erythematosus

2010 ◽  
Vol 37 (11) ◽  
pp. 2268-2272 ◽  
Author(s):  
YI YOU ◽  
ZHE WANG ◽  
GUO-HONG DENG ◽  
YI LIU ◽  
FEI HAO
Keyword(s):  
Systemic Lupus Erythematosus ◽  
Lupus Erythematosus ◽  
Mononuclear Cells ◽  
Gene Promoter ◽  
Chinese Patients ◽  
Luciferase Reporter ◽  
Functional Evaluation ◽  
Reporter System ◽  
Systemic Lupus ◽  
Peripheral Blood Mononuclear

Objective.Signaling lymphocytic activation molecule (SLAM) has been related to the pathology of systemic lupus erythematosus (SLE) through regulation of T cell-dependent humoral immune responses. We investigated the functional associations of the −262A/T and −188A/G polymorphisms of SLAM in Chinese patients with SLE.Methods.Genotyping of −262A/T (rs2295614) and −188A/G (rs2295613) in SLAM was carried out in 248 cases and 278 controls. Promoter activities of haplotypes on the SLAM gene were evaluated with the dual-luciferase reporter system. The mRNA expressions of SLAM on peripheral blood mononuclear cells (PBMC) of SLE patients with different genotypes were determined by real-time polymerase chain reaction.Results.Frequencies of −262A allele and −188G allele were significantly higher in SLE patients than in controls. Haplotype analysis and multifactorial logistic regression analysis showed that individuals with the AG/AG haplotype had increased susceptibility to SLE (p = 0.002, OR 1.478, 95% CI 1.152–1.897). In response to PHA stimulation, the SLAM mRNA expression on PBMC of SLE patients was significantly higher in −262A-188G haplotype homozygotes compared with −262A-188G heterozygotes and individuals with other genotypes.Conclusion.Our findings suggest that −262A-188G haplotype in the SLAM gene promoter contributes to the risk of SLE by increasing the expression of SLAM.

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 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.

scholarly journals Let-7a regulates EV secretion and mitochondrial oxidative phosphorylation by targeting SNAP23 in colorectal cancer

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
You Dong Liu ◽  
Xiao Peng Zhuang ◽  
Dong Lan Cai ◽  
Can Cao ◽  
Qi Sheng Gu ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
Metabolic Reprogramming ◽  
Luciferase Reporter ◽  
Mitochondrial Oxidative Phosphorylation ◽  
In Vivo Assays ◽  
Reporter Assays ◽  
Extracellular Mirna

Abstract Background MicroRNAs (miRNAs) are abundant in tumor-derived extracellular vesicles (EVs) and the functions of extracellular miRNA to recipient cells have been extensively studied with tumorigenesis. However, the role of miRNA in EV secretion from cancer cells remains unknown. Methods qPCR and bioinformatics analysis were applied for determining extracellular let-7a expression from CRC patient serum and cells. Nanosight particle tracking analysis was performed for investigating the effect of let-7a on EV secretion. Luciferase reporter assays was used for identifying targeted genes synaptosome-associated protein 23 (SNAP23). In vitro and in vivo assays were used for exploring the function of let-7a/SNAP23 axis in CRC progression. Bioenergetic assays were performed for investigating the role of let-7a/SNAP23 in cellular metabolic reprogramming. Results let-7a miRNA was elevated in serum EVs from CRC patients and was enriched in CRC cell-derived EVs. We determined that let-7a could suppress EV secretion directly targeting SNAP23. In turn, SNAP23 promotes EV secretion of let-7a to downregulate the intracellular let-7a expression. In addition, we found a novel mechanism of let-7a/SNAP23 axis by regulating mitochondrial oxidative phosphorylation (OXPHOS) through Lin28a/SDHA signaling pathway. Conclusions Let-7a plays an essential role in not only inhibiting EV secretion, but also suppressing OXPHOS through SNAP23, resulting in the suppression of CRC progression, suggesting that let-7a/SNAP23 axis could provide not only effective tumor biomarkers but also novel targets for tumor therapeutic strategies.

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