scholarly journals Glucocorticoid inhibition of human SP-A1 promoter activity in NCI-H441 cells

1999 ◽  
Vol 340 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Russell R. HOOVER ◽  
Klaus H. THOMAS ◽  
Joanna FLOROS
Keyword(s):  
Protein Complex ◽  
Promoter Activity ◽  
Nuclear Extract ◽  
Surfactant Protein ◽  
Inhibitory Effect ◽  
Mrna Levels ◽  
Cis Acting ◽  
Lung Adenocarcinoma Cell Line ◽  
Dose Dependent Decrease ◽  
Dose Dependent

Glucocorticoids have complex effects on human surfactant protein (SP) SP-A1 and SP-A2 gene expression that occur at both transcriptional and post-transcriptional levels. In the lung adenocarcinoma cell line NCI-H441, dexamethasone causes a dose-dependent decrease in total SP-A mRNA levels and inhibits SP-A gene transcription. In this study, a deletional analysis of the SP-A1 promoter was performed in order to identify cis-acting elements that mediate dexamethasone responsiveness in NCI-H441 cells. The region -32/+63 relative to the start of SP-A1 transcription mediated both basal promoter activity and dexamethasone repression of transcription. Removal of the region +18/+63 abolished dexamethasone responsiveness, indicating that sequences within this region are necessary for the inhibitory effect. Furthermore, the region -32/+63 formed a sequence-specific DNA-protein complex with NCI-H441 nuclear extract. This DNA-protein complex was induced by dexamethasone exposure and its formation was mediated partially by sequences within the region +26/+63.

SP-A 3′-UTR is involved in the glucocorticoid inhibition of humanSP-Agene expression

1999 ◽  
Vol 276 (6) ◽  
pp. L917-L924 ◽  
Author(s):  
Russell R. Hoover ◽  
Joanna Floros
Keyword(s):  
Mrna Stability ◽  
Untranslated Region ◽  
Surfactant Protein ◽  
Inhibitory Effect ◽  
Inhibitory Response ◽  
Differential Regulation ◽  
Adenocarcinoma Cell Line ◽  
Adenocarcinoma Cell ◽  
Cis Acting ◽  
Lung Adenocarcinoma Cell Line

The synthetic glucocorticoid dexamethasone has a major inhibitory effect on human surfactant protein A1 ( SP-A1) and SP-A2 gene expression that occurs at both the transcriptional and posttranscriptional levels. Toward the identification of cis-acting elements that may be involved in the dexamethasone regulation of SP-A mRNA stability, chimeric chloramphenicol acetyltransferase (CAT) constructs that contained various portions of SP-A1 or SP-A2 cDNA in place of the native CAT 3′-untranslated region (UTR) were transiently transfected into the lung adenocarcinoma cell line NCI-H441. CAT activity was reduced in NCI-H441 cells by exposure to 100 nM dexamethasone only for the chimeric CAT constructs that contained the SP-A 3′-UTR. Moreover, the inhibitory response seen with dexamethasone was greater for the 3′-UTR derived from the SP-A1 allele 6A3than with the 3′-UTR derived from either the SP-A1 allele 6A2or SP-A2 allele 1A0, indicating differential regulation between SP-Agenes and/or alleles.

Evidence that estrogen receptor β enhances MMP-13 promoter activity in HIG-82 cells and that this enhancement can be influenced by ligands and involves specific promoter sites

2007 ◽  
Vol 85 (3) ◽  
pp. 326-336 ◽  
Author(s):  
Ting Lu ◽  
Yamini Achari ◽  
Jerome B. Rattner ◽  
David A. Hart
Keyword(s):  
Estrogen Receptor ◽  
Promoter Activity ◽  
Estrogen Receptor Β ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Connective Tissues ◽  
Matrix Metalloproteinase 13 ◽  
Promoter Construct ◽  
The Impact ◽  
Dose Dependent

Degradation of articular cartilage is characteristic of osteoarthritis, and matrix metalloproteinase-13 (MMP-13) has been implicated in this condition. Estrogen receptors (ERs) are present in connective tissues, indicating these tissues' potential responsiveness to estrogen. We based this study on the hypothesis that estrogen receptor β (ERβ) can modulate MMP-13 promoter activity. Transfection of cells with ERβ constructs led to the induction of the endogenous MMP-13 gene, as evidenced by increased mRNA levels. The results also indicated that MMP-13 promoter construct activity in the HIG-82 cell line significantly increased when ERβ was present, and that estrogen downregulated this response in a dose-dependent manner. ERβ was shown to enhance MMP-13 expression somewhat more strongly than ERα, and the impact of a number of selective ER modulators (tamoxifen, raloxifene, and ICI 182,780) on ERβ enhancement of promoter activity was found to be significantly less than that of estrogen. Furthermore, transcription regulatory sites in the MMP-13 promoter, specifically AP-1 and PEA-3, were shown to act in conjunction to mediate ERβ effects. Thus, ERβ likely influences MMP-13 promoter expression in normal and disease processes.

The effect of epitestosterone on gonadotrophin synthesis and secretion

1994 ◽  
Vol 143 (2) ◽  
pp. 353-358 ◽  
Author(s):  
O Lapcik ◽  
A Perheentupa ◽  
M Bicikova ◽  
I Huhtaniemi ◽  
R Hampl ◽  
...  
Keyword(s):  
Significant Negative Correlation ◽  
Inhibitory Effect ◽  
Male Rats ◽  
Mrna Levels ◽  
Α Subunit ◽  
Direct Inhibitory Effect ◽  
Testosterone Effect ◽  
Dose Dependent ◽  
Circulating Levels ◽  
Hypothalamic Level

Abstract The effects of 3-week treatment with increasing doses of epitestosterone (ET) on gonadotrophin gene expression and secretion, on testosterone and 5α-dihydrotestosterone (DHT) levels, and on the weight of testes and prostates, were studied in intact adult male rats. The hormones were delivered by means of silastic capsules of different lengths filled with the steroid. One group of rats received testosterone (T) instead of ET, to compare the results with previous studies concerning the testosterone effect. The controls were given capsules with glucose only. Treatment with ET, as well as with T, significantly reduced the weights of prostates. When the data from ET-treated rats and controls were combined, a significant negative correlation (P<0·001) was found between the weight of prostates and serum ET. T, in contrast to ET, also decreased significantly the weights of testes. ET treatment caused a significant reduction of serum T levels but only an insignificant decline of DHT levels, independent of the dose. Serum and pituitary (p) luteinizing hormone (LH) levels in the ET-treated rats did not change. Pituitary mRNA contents for the βLH subunit (βLH-mRNA) showed a dose-dependent significant increase, up to 170% (P<0·01), with ET treatment. pFSH decreased with the lowest ET (2 cm) dose (P<0·05), but no change was observed with the other doses. The mRNA for the common α-subunit also increased with the ET load. In conclusion, ET acts at several sites in the regulation of gonadotrophin formation and release. It enhances the steady-state mRNA levels of both gonadotrophins in the pituitary. At the same time, ET may act directly in the pituitary by inhibition of post-transcriptional events in LH synthesis. A direct inhibitory effect of ET at the hypothalamic level is also possible. The circulating levels of both gonadotrophins are thus the result of these composite effects. Journal of Endocrinology (1994) 143, 353–358

3,3′,5′-Triiodothyronine inhibits ontogenetic development of iodothyronine-5′-deiodinase in the liver of the neonatal mouse

1988 ◽  
Vol 119 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Doo Chol Han ◽  
Kanji Sato ◽  
Yuko Fujii ◽  
Minoru Ozawa ◽  
Hidehito Imamura ◽  
...  
Keyword(s):  
Single Injection ◽  
Inhibitory Effect ◽  
Antagonistic Effect ◽  
Time Dependent ◽  
Dependent Manner ◽  
Neonatal Mice ◽  
Dose Dependent Decrease ◽  
Dose Dependent

Abstract. To elucidate the effect of rT3 on iodothyronine-5′-deiodinating activity (I-5′-DA) in the liver of neonatal mice, rT3 was injected sc on the 5–8th day after birth and I-5′-DA in the liver was determined. A single injection of rT3 (0.01–1 μg/g) inhibited the ontogenetically developing I-5′-DA in a dose- and time-dependent manner. The inhibitory effect was reversible and specific for I-5′-DA. Lineweaver-Burk analysis revealed that the time- and dose-dependent decrease in the enzyme activity was due to a decrease in Vmax with no alteration in Km values (5 × 10−8 mol/l). The maximal inhibitory effect was observed at a dose of 1 μg rT3/g, whereas the inhibitory effect was diminished at greater doses (4–10 μg/g), probably owing to a contamination with T4 of the rT3 preparation administered. Furthermore, consistent with our previous in vitro findings, rT3 inhibited the I-5′-DA induced by T3 in the liver of neonatal mice. These findings suggest that rT3 inhibited I-5′-DA in the liver of neonatal mice by decreasing the amount of enzyme available to the substrate and that rT3 also elicited an antagonistic effect against T3 in the induction of I-5′-DA in vivo.

scholarly journals SF002-96-1, a new drimane sesquiterpene lactone from an Aspergillus species, inhibits survivin expression

2013 ◽  
Vol 9 ◽  
pp. 2866-2876 ◽  
Author(s):  
Silke Felix ◽  
Louis P Sandjo ◽  
Till Opatz ◽  
Gerhard Erkel
Keyword(s):  
Sesquiterpene Lactone ◽  
Promoter Activity ◽  
Survivin Expression ◽  
Anticancer Therapy ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Survivin Promoter ◽  
Apoptosis Gene ◽  
Apoptosis Regulation ◽  
Dose Dependent

Survivin, a member of the IAP (inhibitor of apoptosis) gene family, is overexpressed in virtually all human cancers and is functionally involved in the inhibition of apoptosis, regulation of cell proliferation, metastasis and resistance to therapy. Because of its upregulation in malignancy, survivin has currently attracting considerable interest as a new target for anticancer therapy. In a screening of approximately 200 strains of imperfect fungi for the production of inhibitors of survivin promoter activity, a new drimane sesquiterpene lactone, SF002-96-1, was isolated from fermentations of an Aspergillus species. The compound inhibited survivin promoter activity in transiently transfected Colo 320 cells in a dose dependent manner with IC50 values of 3.42 µM (1.3 µg/mL). Moreover, it also reduced mRNA levels and protein synthesis of survivin and triggered apoptosis.

Downregulation of the PTH/PTHrP receptor by vitamin D3 in the osteoblast-like ROS 17/2.8 cells

1996 ◽  
Vol 270 (4) ◽  
pp. E654-E660 ◽  
Author(s):  
L. Y. Xie ◽  
A. Leung ◽  
G. V. Segre ◽  
I. Yamamoto ◽  
A. B. Abou-Samra
Keyword(s):  
Receptor Gene ◽  
Inhibitory Effect ◽  
Receptor Protein ◽  
Mrna Levels ◽  
Dihydroxyvitamin D3 ◽  
Low Concentrations ◽  
Potent Inhibitory Effect ◽  
Receptor Number ◽  
Pthrp Receptor ◽  
Dose Dependent

Effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the expression of the parathyroid hormone (PTH)/PTH-related peptide (rP) receptor protein and mRNA in ROS 17/2.8 cells were studied. Treatment of ROS 17/2.8 cells with 1,25(OH)2D3 caused time- and dose-dependent suppression of PTH/PTHrP receptor number and immunoreactivity. The effects required more than 24 h incubation with 1,25(OH)2D3 and were maximal by 72 h. The cells did not recover their PTH/PTHrP receptors even after 4 days of treatment with control medium. Treatment with low concentrations of 1,25(OH)2D3 (0.1 M) dramatically decreased the PTH/PTHrP receptor mRNA levels, which were maximal after 24 h of incubation. The half-life of the PTH/PTHrP receptor transcript, 6-8 h, was similar in control and 1,25(OH)2D3-treated cells, suggesting that 1,25(OH)2D3 acts in controlling transcription of the PTH/PTHrP receptor gene but does not change the degradation rate of the PTH/PTHrP receptor transcripts. These data indicate that 1,25(OH)2D3 has a potent inhibitory effect on the expression of the PTH/PTHrP receptor protein and mRNA in ROS 17/2.8 cells.

scholarly journals Heterologous expression of rab4 reduces glucose transport and GLUT4 abundance at the cell surface in oocytes

1997 ◽  
Vol 324 (2) ◽  
pp. 455-459 ◽  
Author(s):  
Silvia MORA ◽  
Ingrid MONDEN ◽  
Antonio ZORZANO ◽  
Konrad KELLER
Keyword(s):  
Cell Surface ◽  
Glucose Transport ◽  
Glucose Transporter ◽  
Glucose Transporters ◽  
Inhibitory Effect ◽  
Trafficking Pathway ◽  
Independent Mechanism ◽  
Dose Dependent Decrease ◽  
Dose Dependent

To evaluate the role of the small rab GTP-binding proteins in glucose transporter trafficking, we have heterologously co-expressed rab4 or rab5 and GLUT4 or GLUT1 glucose transporters in Xenopus oocytes. Co-injection of rab4 and GLUT4 cRNAs resulted in a dose-dependent decrease in glucose transport; this effect was specific for rab4, since co-injection of an inactive rab4 mutant or rab5 cRNA did not have any effect on glucose transport. The effect of rab4 was selective for GLUT4, since no effect was detected in GLUT1-expressing oocytes. The inhibitory effect of rab4 on GLUT4-induced glucose transport was not the result of a change in overall cellular levels of GLUT4 glucose transporters. However, rab4 expression caused a marked decrease in the abundance of GLUT4 transporters present at the cell surface. Finally, rab4 and inhibitors of PtdIns 3-kinase showed additive effects in decreasing glucose transport in GLUT4-expressing oocytes. We conclude that rab4 plays an important role in the regulation of the intracellular GLUT4 trafficking pathway, by contributing to the intracellular retention of GLUT4 through a PtdIns 3-kinase-independent mechanism.

Concurrent generation of nitric oxide and superoxide damages surfactant protein A

1994 ◽  
Vol 267 (3) ◽  
pp. L242-L249 ◽  
Author(s):  
I. Y. Haddad ◽  
J. P. Crow ◽  
P. Hu ◽  
Y. Ye ◽  
J. Beckman ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Hydrogen Peroxide ◽  
Xanthine Oxidase ◽  
Protein A ◽  
Surfactant Protein ◽  
Simultaneous Generation ◽  
Tyrosine Residues ◽  
Dose Dependent Decrease ◽  
Dose Dependent

The conditions under which nitric oxide (.NO) may modulate or promote lung injury have not been identified. We hypothesized that .NO-induced injury results from peroxynitrite, formed by the reaction of .NO with superoxide. The simultaneous generation of .NO and superoxide by 3-morpholinosydnonimine (SIN-1, 0.1-2 mM) resulted in oxidation of dihydrorhodamine, a marker of peroxynitrite production, and a dose-dependent decrease in the ability of SP-A to enhance lipid aggregation. Western blot analysis of SIN-1 exposed SP-A samples, overlaid with a polyclonal antibody against nitrotyrosine, were consistent with nitration of SP-A tyrosine residues. Superoxide dismutase (100 U/ml), L-cysteine (5 mM), xanthine oxidase (10 mU/ml) and xanthine (500 microM), or urate (100 microM) prevented the SIN-1-induced dihydrorhodamine oxidation and injury to SP-A. .NO alone, generated by S-nitroso-N-acetylpenicillamine plus 100 microM L-cysteine, or superoxide and hydrogen peroxide, generated by pterin and xanthine oxidase in the absence of iron, did not damage SP-A or oxidize dihydrorhodamine. We concluded that peroxynitrite, but not .NO or superoxide and hydrogen peroxide, in concentrations likely to be encountered in vivo, caused nitrotyrosine formation and decreased the ability of SP-A to aggregate lipids.

Surfactant protein C: hormonal control of SP-C mRNA levels in vitro

1992 ◽  
Vol 262 (6) ◽  
pp. L684-L687 ◽  
Author(s):  
S. V. Veletza ◽  
K. V. Nichols ◽  
I. Gross ◽  
H. Lu ◽  
D. W. Dynia ◽  
...  
Keyword(s):  
Hormonal Regulation ◽  
Protein C ◽  
Cdna Probe ◽  
Surfactant Protein ◽  
Hormonal Control ◽  
Mrna Levels ◽  
Cyclic Monophosphate ◽  
Surfactant Protein C ◽  
Dose Dependent Increase ◽  
Dose Dependent

We have studied hormonal regulation of the surfactant protein C (SP-C) in fetal 18-dah rat lung explants. SP-C mRNA was detected in Northern blots with a specific rat SP-C cDNA probe and quantified by densitometry. Treatment of the explants with dexamethasone resulted in a dose-dependent increase of the SP-C mRNA level. Transcriptional assays have shown that the regulation of SP-C mRNA by dexamethasone involves a transcriptional step. Administration of the cAMP analogues, 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP) or dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP), produced a dose-dependent increase of SP-C mRNA levels, with maximum stimulation observed at 200 microM. The thyroid hormone T3 had no effect on SP-C mRNA levels, whether administered alone or in combination with dexamethasone. Variation in the effects of the above hormones on three surfactant protein mRNAs, SP-A, SP-B and SP-C, indicates that the hormonal regulation of the surfactant proteins is a complex process and that each gene is, in part, differentially regulated.

Hyperosmotic stress stimulates tissue plasminogen activator expression by a PKC-independent pathway

1993 ◽  
Vol 265 (2) ◽  
pp. C387-C396 ◽  
Author(s):  
E. G. Levin ◽  
L. Santell ◽  
F. Saljooque
Keyword(s):  
Environmental Stress ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Hela Cells ◽  
Fold Increase ◽  
Mrna Levels ◽  
Tissue Plasminogen ◽  
Dose Dependent Decrease ◽  
Dose Dependent ◽  
Hyperosmotic Environment

Shear, stretch, and the generation of oxygen radicals stimulate increases in tissue plasminogen activator (t-PA) mRNA levels and antigen production, suggesting that environmental stress may regulate t-PA gene expression. We have examined whether t-PA production is also responsive to a hyperosmotic environment. Endothelial and HeLa cells were treated with hyperosmotic medium, and t-PA mRNA and antigen secretion were measured. Endothelial cells incubated in hyperosmotic medium showed a dose-dependent decrease in cell volume and a 1.9 +/- 0.3- and 3.7 +/- 0.9-fold increase in t-PA secretion at 425 and 485 mosmol/kgH2O, respectively. HeLa cells showed a 3.3 +/- 0.6- and 5.1 +/- 1.2-fold increase at the same osmolalities. Increased secretion began between 8 and 16 h and continued through 24 h. Cultures returned to isosmotic medium after 8 h of treatment continued to release 98.1 +/- 7% of the maximum levels of t-PA for the next 16 h, despite the reversal of other responses to hyperosmotic environment. t-PA mRNA levels also increased between 8 and 16 h to five times control levels but returned to baseline by 24 h. No change in intracellular Ca2+ concentration, inositol 1,4,5-trisphosphate, or diacylglycerol content was detected, suggesting that a different intracellular signal pathway may be involved in the response to hyperosmolar stimulus. Thus environmental stress may be a general stimulatory signal through which t-PA production can be induced.

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