scholarly journals Mechanical Stretch Up-Regulates the Human Oxytocin Receptor in Primary Human Uterine Myocytes

2005 ◽  
Vol 90 (1) ◽  
pp. 237-246 ◽  
Author(s):  
Vasso Terzidou ◽  
Suren R. Sooranna ◽  
Louise U. Kim ◽  
Steve Thornton ◽  
Phillip R. Bennett ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Dna Binding ◽  
Mrna Expression ◽  
Promoter Activity ◽  
Primary Cultures ◽  
Mechanical Stretch ◽  
Nuclear Factor Κb ◽  
Oxytocin Receptor ◽  
Nuclear Factor ◽  
L Cells

Abstract Oxytocin receptor (OTR) expression is increased before the onset of labor in all models of parturition. However, the mechanisms responsible for the increase in OTR expression are uncertain. Animal data suggest that uterine stretch increases OTR mRNA expression. In primary cultures of human uterine smooth muscle cells obtained from nonpregnant (NP) women and pregnant women before (NL) and after (L) the onset of labor, we investigated the effect of stretch on the expression of OTR mRNA and DNA binding of activator protein-1 (AP-1), CCAAT/enhancer binding protein (C/EBP)β, and nuclear factor-κB transcription factors. OTR expression was least in NL, intermediate in NP, and greatest in L cells. Stretch of NL cells resulted in up-regulation of OTR mRNA expression associated with increased OTR gene promoter activity. Stretch of NP and L cells did not affect OTR mRNA expression. The increased promoter activity was associated with increased DNA binding of C/EBP and AP-1 but not nuclear factor-κB transcription factors. Overexpression of C/EBP, but not AP-1, increased OTR promoter activity. We conclude that stretch of NL cells results in increased OTR mRNA expression probably through increased C/EBPβ DNA binding. These data suggest that stretch contributes to the massive increase in OTR expression before the onset of human labor.

scholarly journals Degradation of Promoter-bound p65/RelA Is Essential for the Prompt Termination of the Nuclear Factor κB Response

2004 ◽  
Vol 200 (1) ◽  
pp. 107-113 ◽  
Author(s):  
Simona Saccani ◽  
Ivan Marazzi ◽  
Amer A. Beg ◽  
Gioacchino Natoli
Keyword(s):  
Transcription Factors ◽  
Dna Binding ◽  
Target Genes ◽  
Proteasomal Degradation ◽  
Nuclear Factor Κb ◽  
Proteasome Activity ◽  
Dependent Manner ◽  
Nuclear Factor ◽  
Transcriptional Termination

Transcription factors of the nuclear factor (NF)-κB/Rel family translocate into the nucleus upon degradation of the IκBs. Postinduction repression of NF-κB activity depends on NF-κB–regulated resynthesis of IκBα, which dissociates NF-κB from DNA and exports it to the cytosol. We found that after activation, p65/RelA is degraded by the proteasome in the nucleus and in a DNA binding–dependent manner. If proteasome activity is blocked, NF-κB is not promptly removed from some target genes in spite of IκBα resynthesis and sustained transcription occurs. These results indicate that proteasomal degradation of p65/RelA does not merely regulate its stability and abundance, but also actively promotes transcriptional termination.

Effect of ciprofloxacin on the activation of the transcription factors nuclear factor κB, activator protein-1 and nuclear factor-interleukin-6, and interleukin-6 and interleukin-8 mRNA expression in a human endothelial cell line

2000 ◽  
Vol 99 (5) ◽  
pp. 405-410 ◽  
Author(s):  
Helen F. GALLEY ◽  
Jatinder K. DHILLON ◽  
Ross L. PATERSON ◽  
Nigel R. WEBSTER
Keyword(s):  
Transcription Factors ◽  
Endothelial Cell ◽  
Mrna Expression ◽  
Cell Line ◽  
Nuclear Factor Κb ◽  
Human Endothelial Cell ◽  
Nuclear Factor ◽  
Activator Protein 1 ◽  
Endothelial Cell Line ◽  
Human Endothelial Cell Line

Quinolone antibiotics such as ciprofloxacin modify immune and inflammatory responses in some cells. We have shown previously that ciprofloxacin decreases the accumulation of interleukin (IL)-6 protein from a human endothelial cell line, whilst IL-8 protein production was increased. It is not known whether this occurs through effects on transcription and mRNA expression. We therefore investigated the effect of ciprofloxacin on mRNA for IL-6 and IL-8, and on three transcription factors known to be involved in the regulation of these cytokines. We investigated the effect of ciprofloxacin on tumour necrosis factor α- and IL-1β-mediated activation of the transcription factors nuclear factor κB (NFκB), activator protein-1 (AP-1) and nuclear factor IL-6 (NF-IL-6) using an electrophoretic mobility shift assay, and the effect on expression of mRNA for IL-6 and IL-8 by reverse transcriptase–PCR in the EAhy926 endothelial cell line. Ciprofloxacin decreased IL-6 mRNA (P < 0.05) and increased IL-8 mRNA (P < 0.05) expression. Ciprofloxacin did not modulate activation of NFκB or AP-1. However, NF-IL-6 binding was decreased in the presence of 100 µg/ml ciprofloxacin (P < 0.05). The study shows that ciprofloxacin-mediated decreased IL-6 release by a human endothelial cell line is reflected by decreased mRNA expression and decreased NF-IL-6 but not NFkB or AP-1 activation. Increased IL-8 mRNA in response to ciprofloxacin was not reflected by altered transcription factor activation and may represent increased mRNA stability.

A direct requirement of nuclear factor-κB for suppression of apoptosis in ventricular myocytes

2000 ◽  
Vol 279 (3) ◽  
pp. H939-H945 ◽  
Author(s):  
Shareef Mustapha ◽  
Alla Kirshner ◽  
Danielle De Moissac ◽  
Lorrie A. Kirshenbaum
Keyword(s):  
Dna Binding ◽  
Gene Transcription ◽  
Ventricular Myocytes ◽  
Vital Staining ◽  
Fold Increase ◽  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Cytoplasmic Factor ◽  
Tnf Α ◽  
Factor Α

Nuclear factor-κB (NF-κB) is a ubiquitously expressed cellular factor regulated by the cytoplasmic factor inhibitor protein κBα (IκBα). Activation of NF-κB by cytokines, including tumor necrosis factor-α (TNF-α), requires the phosphorylation and degradation of IκBα. An anti-apoptotic role for NF-κB has recently been suggested. In the present study, we ascertained whether death-promoting signals and apoptosis mediated by TNF-α are suppressed by NF-κB in postnatal ventricular myocytes. Stimulation of myocytes with TNF-α resulted in a 12.1-fold increase ( P < 0.01) in NF-κB-dependent gene transcription and DNA binding compared with controls. This was accompanied by a corresponding increase in the NF-κB target protein A20 as determined by Western blot analysis. Vital staining revealed that TNF-α was not cytotoxic to myocytes and did not provoke apoptosis. Adenovirus-mediated delivery of a nonphosphorylatable form of IκBα to inactivate NF-κB prevented TNF-α-stimulated NF-κB-dependent gene transcription and nuclear NF-κB DNA binding. Importantly, myocytes stimulated with TNF-α and defective for NF-κB activation resulted in a 2.2-fold increase ( P < 0.001) in apoptosis. To our knowledge, the data provide the first indication that a functional NF-κB signaling pathway is crucial for suppressing death-promoting signals mediated by TNF-α in ventricular myocytes.

UV stimulation induces nuclear factor κB (NF-κB) DNA-binding activity but not transcriptional activation

2001 ◽  
Vol 29 (6) ◽  
pp. 688-691 ◽  
Author(s):  
K. J. Campbell ◽  
N. R. Chapman ◽  
N. D. Perkins
Keyword(s):  
Dna Binding ◽  
Transcriptional Activation ◽  
Cellular Response ◽  
Uv Light ◽  
Binding Protein ◽  
Nuclear Factor Κb ◽  
Camp Response Element Binding ◽  
Binding Activity ◽  
Nuclear Factor ◽  
Dna Binding Activity

The cellular response to DNA-damaging agents is partly mediated by DNA-binding transcription factors such as p53 and nuclear factor κB (NF-κB). Typically NF-κB activation is associated with resistance to apoptosis. Following stimulation with UV light however, NF-κB activation has been shown to be required for programmed cell death. To study this effect further and to determine the relationship between NF-κB and p53 function, we have examined the effect of UV light on U2OS cells. UV stimulation resulted in the activation of NF-κB DNA-binding and the induction of p53. Surprisingly, and in contrast with tumour necrosis factor α stimulation, this UV-induced NF-κB was transcriptionally inert. These observations suggest a model in which the NF-κB switch from an anti-apoptotic to a pro-apoptotic role within the cell results from modulation of its ability to stimulate gene expression, possibly as a result of the ability of p53 to sequester transcriptional co-activator proteins such as p300/CREB (cAMP-response-element-binding protein)-binding protein.

Role of nuclear factor-κB in gastric ulcer healing in rats

2001 ◽  
Vol 280 (6) ◽  
pp. G1296-G1304 ◽  
Author(s):  
Satoru Takahashi ◽  
Takuya Fujita ◽  
Akira Yamamoto
Keyword(s):  
Gastric Ulcer ◽  
Mrna Expression ◽  
Ulcer Healing ◽  
Nuclear Factor Κb ◽  
Normal Mucosa ◽  
Cyclooxygenase 2 ◽  
Interleukin 1Β ◽  
Nuclear Factor ◽  
Gastric Ulcer Healing

We investigated the role of nuclear factor-κB (NF-κB) in gastric ulcer healing in rats. NF-κB was activated in ulcerated tissue but not in normal mucosa, and the level of the activation was decreased with ulcer healing. NF-κB activation was observed in fibroblasts, monocytes/macrophages, and neutrophils. Treatment of gastric fibroblasts, isolated from the ulcer base, with interleukin-1β activated NF-κB and the subsequently induced cyclooxygenase-2 and cytokine-induced neutrophil chemoattractant-1 (CINC-1) mRNA expression. Inhibition of activated NF-κB action resulted in suppression of both their mRNA expression and increases in PGE2 and CINC-1 levels induced by interleukin-1β. Persistent prevention of NF-κB activation caused an impairment of ulcer healing in rats. Gene expression of interleukin-1β, CINC-1, cyclooxygenase-2, and inducible nitric oxide synthase in ulcerated tissue had been inhibited before the delay in ulcer healing became manifest. The increased levels of cyclooxygenase-2 protein and PGE2 production were also reduced. These results demonstrate that NF-κB, activated in ulcerated tissue, might upregulate the expression of healing-promoting factors responsible for gastric ulcer healing in rats.

Bafilomycin A1inhibits rhinovirus infection in human airway epithelium: effects on endosome and ICAM-1

2001 ◽  
Vol 280 (6) ◽  
pp. L1115-L1127 ◽  
Author(s):  
Tomoko Suzuki ◽  
Mutsuo Yamaya ◽  
Kiyohisa Sekizawa ◽  
Masayoshi Hosoda ◽  
Norihiro Yamada ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Airway Epithelium ◽  
Primary Cultures ◽  
Nuclear Factor Κb ◽  
Intercellular Adhesion Molecule ◽  
Nuclear Factor ◽  
Tracheal Epithelial Cells ◽  
Before And After ◽  
Infected Cells ◽  
Viral Titers

To examine the effects of bafilomycin A1, a blocker of vacuolar H+-ATPase, on rhinovirus (RV) infection in the airway epithelium, primary cultures of human tracheal epithelial cells were infected with RV14. Viral infection was confirmed by showing that viral RNA in the infected cells and the viral titers in the supernatants of infected cells increased with time. RV14 infection upregulated the production of cytokines and mRNA of intercellular adhesion molecule (ICAM)-1 in epithelial cells. Bafilomycin A1reduced the viral titers of RV14 and inhibited the production of cytokines and ICAM-1 before and after RV14 infection. Bafilomycin A1reduced susceptibility of epithelial cells to RV14 infection. RV14 increased activated nuclear factor-κB in the cells, and bafilomycin A1reduced the activated nuclear factor-κB. Bafilomycin A1decreased the number of acidic endosomes in the epithelial cells. These results suggest that bafilomycin A1may inhibit infection by RV14 by not only blocking RV RNA entry into the endosomes but also reducing ICAM-1 expression in the epithelial cells. Bafilomycin A1may therefore modulate airway inflammation after RV infection.

Activation of transcription factors activator protein-1 and nuclear factor-κB by 2,3,7,8-Tetrachlorodibenzo-p-dioxin

2000 ◽  
Vol 59 (8) ◽  
pp. 997-1005 ◽  
Author(s):  
Alvaro Puga ◽  
Sonya J Barnes ◽  
Ching-yi Chang ◽  
Huan Zhu ◽  
Kenneth P Nephew ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Activator Protein 1 ◽  
Activator Protein ◽  
Activation Of Transcription ◽  
Tetrachlorodibenzo P Dioxin

Regulation of growth and apoptosis of cultured guinea pig gastric mucosal cells by mitogenic oxidase 1

2000 ◽  
Vol 279 (6) ◽  
pp. G1169-G1176 ◽  
Author(s):  
Shigetada Teshima ◽  
Hiromu Kutsumi ◽  
Tsukasa Kawahara ◽  
Kyoichi Kishi ◽  
Kazuhito Rokutan
Keyword(s):  
Guinea Pig ◽  
Chromatin Condensation ◽  
Primary Cultures ◽  
Nuclear Factor Κb ◽  
Thymidine Uptake ◽  
Nuclear Factor ◽  
Spontaneous Apoptosis ◽  
Oxygen Intermediates ◽  
Diphenylene Iodonium ◽  
Pit Cells

We previously reported that primary cultures of guinea pig gastric pit cells expressed all of the phagocyte NADPH oxidase components (gp91-, p22-, p67-, p47-, and p40- phox) and could spontaneously release superoxide anion (O2−). We demonstrate here that pit cells express a nonphagocyte-specific gp91- phox homolog (Mox1) but not gp91- phox. Inclusion of catalase significantly inhibited [3H]thymidine uptake during the initial 2 days of culture. Pit cells, matured on day 2, slowly underwent spontaneous apoptosis. Scavenging O2−and related oxidants by superoxide dismutase plus catalase or N-acetyl cysteine (NAC) and inhibiting Mox1 oxidase by diphenylene iodonium activated caspase 3-like proteases and markedly enhanced chromatin condensation and DNA fragmentation. This accelerated apoptosis was completely blocked by a caspase inhibitor, z-Val-Ala-Asp-CH2F. Mox1-derived reactive oxygen intermediates constitutively activated nuclear factor-κB, and inhibition of this activity by nuclear factor-κB decoy oligodeoxynucleotide accelerated their spontaneous apoptosis. These results suggest that O2−produced by the pit cell Mox1 oxidase may play a crucial role in the regulation of their spontaneous apoptosis as well as cell proliferation.

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