Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.1 (phosphodiesterase)
18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the involvement of the cAMP pathway in the regulation of beta TC1 cell growth with the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) and the activator of adenylate cyclase forskolin. We examined the effect of the increase in cAMP content on the serum-induced resumption of the cell cycle of quiescent cells. IBMX and forskolin both inhibited the mitogenic effect of serum in a concentration-dependent manner. Intracellular cAMP levels were, respectively, enhanced 3.0- and 8.6-fold by IBMX (0.5 mM) and forskolin (20 microM) within 1 h. IBMX and forskolin were also inducers of insulin release, indicating that the growth-arrested beta TC1 cells have retained the essential characteristics of the normal differentiated beta-cells. The effects of IBMX and forskolin were correlated with a modulation of cell cycle-related gene expression. IBMX induced expression of the c-fos gene, which was further enhanced by the simultaneous addition of serum, whereas forskolin alone elicited maximal induction of this gene. Interestingly, c-jun expression was only enhanced with forskolin. We also studied the effects of IBMX and forskolin on the expression of the simian virus-40 T-antigen controlled by the rat insulin II promoter in beta TC1 cells. IBMX and forskolin inhibited the serum-induced accumulation of simian virus-40 T-antigen mRNA in quiescent as well as exponentially growing beta TC1 cells.
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PMID:Modulation of growth-related gene expression and growth inhibition by cyclic adenosine 3',5'-monophosphate-elevating agents in the insulin-producing cell line beta TC1. 138

Regulation of cholecystokinin (CCK) and the proto-oncogene c-fos mRNA expression was studied in the human neuroblastoma cell line SK-N-MC. Cells were treated either with the tumor promoting phorbol-ester phorbol-12-myristate-13-acetate (PMA), the phosphodiesterase inhibitor isobutyl-methylxanthine (IBMX), which results in an elevated intracellular cyclic AMP (cAMP) level, or with a combination of PMA and IBMX. The level of CCK and c-fos mRNA was determined by Northern-blot analysis with CCK and c-fos specific antisense RNA probes after 4-24 h of drug treatment. Treatment with PMA and IBMX for 4-24 hours transiently raised the CCK mRNA level approximately 1.5-3.5 times compared to the controls, and the combination PMA and IBMX had an additive effect and elevated CCK mRNA abundance 1.5-6.5 times. Under the same experimental conditions, both PMA and IBMX elevated the c-fos mRNA level approximately 3-5.5 times. The drug combination showed a pronounced synergistic effect and raised the c-fos mRNA level approximately 3-20 times as compared to controls. Apparently, CCK and c-fos mRNA expression appears to be regulated by similar protein kinase C (PKC) and cAMP-dependent mechanisms in SK-N-MC cells.
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PMID:Phorbol 12-myristate-13-acetate (PMA) stimulates a differential expression of cholecystokinin (CCK) and c-fos mRNA in a human neuroblastoma cell line. 172 Apr 2

We tested the effects of the cyclic AMP-dependent phosphodiesterase inhibitor 4- (3-cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone (rolipram) on c-fos protein-like immunoreactivity (FOS-IR) in adult rat brain. Rolipram (25-100 mg/kg, i.p.) did not detectability alter basal FOS-IR in neurons but induced FOS-IR in glial-like cells scattered in white matter regions and in ependymal cells lining the lateral and third ventricles. This induction was observed at 1 and 4 h after injection but was not detectable 10 min or 24 h after rolipram injection.
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PMID:Rolipram induces c-fos protein-like immunoreactivity in ependymal and glial-like cells in adult rat brain. 251 Sep 5

The hallmark of "beta 2-interferon (IFN-beta 2)/hepatocyte-stimulating factor/interleukin 6" gene expression is its inducibility in different types of human cells (fibroblasts, monocytes, epithelial cells, and endothelial cells) by different stimuli, which include cytokines such as tumor necrosis factor, interleukin 1 (IL-1) and platelet-derived growth factor, different viruses, and bacterial products such as endotoxin. The activation by cytokines, viruses, and second messenger agonists of the IFN-beta 2 promoter linked to the bacterial chloramphenicol acetyltransferase (CAT) gene was studied after transfection into HeLa cells. A chimeric gene containing IFN-beta 2 DNA from -1180 to +13 linked to the CAT gene was inducible approximately 10-fold by phorbol 12-myristate 13-acetate (PMA), followed, in decreasing order, by pseudorabies and Sendai viruses (7- to 11-fold each); serum (6- to 9-fold); the cytokines tumor necrosis factor, IL-1, and epidermal growth factor (3- to 5-fold each); the cAMP agonists BrcAMP and forskolin and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (2- to 6-fold each); poly(I).poly(C) (2- to 4-fold); 1,2-diacylglycerol and the calcium ionophore A23187 (1.5- to 2-fold each). Bacterial endotoxin did not activate this IFN-beta 2/CAT fusion gene in HeLa cells. Deletion of the 5' boundary of the IFN-beta 2 DNA from -1180 to -596 in the fusion gene preserved its activation by IL-1, tumor necrosis factor, epidermal growth factor, serum, pseudorabies, and Sendai viruses and by PMA, Br-cAMP, and forskolin; deletion to -225 led to a small reduction (by a factor of 1.5-2) in the responsiveness to serum, PMA, and Sendai virus but not to the other inducers; a further deletion to -112 greatly reduced all responsiveness. Thus, the region between -225 and -113 in IFN-beta 2, which contains DNA motifs similar to the regulatory elements in the human c-fos gene, appears to contain the major cis-acting regulatory elements responsible for the activation of the IFN-beta 2 promoter by several different cytokines, viruses, and second messenger agonists.
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PMID:Activation of the human "beta 2-interferon/hepatocyte-stimulating factor/interleukin 6" promoter by cytokines, viruses, and second messenger agonists. 304 22

It has previously been shown that caffeine, in a dose-dependent manner, increases the expression of the protooncogene c-fos in the rat brain, predominantly in the caudate-putamen and tuberculum olfactorium. In this study we examined the effect of related xanthines and of selective phosphodiesterase inhibitors on c-fos expression. The effect of caffeine (75 mg kg-1) was mimicked by 3-isobutyl-1-methyl xanthine (IBMX) (25 mg kg-1) and theophylline (100 mg kg-1) but not by 8-p-sulfophenyltheophylline (10 mg kg-1), enprofylline, theobromine or paraxanthine (each at 100 mg kg-1). Moreover, the cyclic AMP-selective phosphodiesterase inhibitors rolipram (10 or 20 mg kg-1) and SQ 20,006 (25 mg kg-1) and the cyclic GMP-selective phosphodiesterase inhibitor zaprinast (10 mg kg-1) failed to induce c-fos in striatum, but caused a clear-cut induction in the overlying cerebral cortex. Thus, c-fos is induced in rat striatum following administration of caffeine and other xanthines that (provided they enter the brain) block adenosine receptors, suggesting an involvement of central adenosine receptors. Inhibition of cyclic nucleotide phosphodiesterase does not appear to play any important role in c-fos induction by the xanthines.
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PMID:Effect of different xanthines and phosphodiesterase inhibitors on c-fos expression in rat striatum. 757 98

A variety of drugs known to act via increasing intracellular cAMP are used in the treatment of asthma. In this study we asked whether anti-asthma drugs are capable of altering gene activation. We determined whether phosphodiesterase inhibitors, either alone or in combination with adrenoceptor agonists, were able to alter the abundance of mRNA of the cAMP responsive gene c-fos in the cell-lines HL60 and U937. Incubation of cells with phosphodiesterase inhibitors aminophylline, theophylline or pentoxyphylline all resulted in an increase in c-fos mRNA. Further upregulation of c-fos mRNA abundance was observed when the cells were stimulated with the combination of aminophylline and adrenoceptor agonists with beta 2-agonist activity. These increases in c-fos mRNA were accompanied by increases in intracellular concentration of cAMP. These data suggest that in these in vitro models, combinations of beta 2-adrenoceptor agonists and phosphodiesterase inhibitors can increase intracellular cAMP and affect gene activation.
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PMID:Pharmacological modulation of c-fos mRNA expression in the HL60 and U937 cell lines. 790 46

Primary cultures of prepubertal rat Sertoli cells secrete two major tissue inhibitors of metalloproteinases: TIMP-1 (M(r) 28K) and TIMP-2 (M(r) 21 K). FSH stimulated Sertoli cell TIMP-1 and TIMP-2 activity in a time- and dose-dependent manner and also stimulated TIMP-1 and TIMP-2 protein and messenger RNA levels. These effects were mimicked by the cAMP analog, 8-bromo-cAMP, and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine. The protein kinase C activating phorbol ester phorbol myristate acetate (TPA) stimulated TIMP-1 but not TIMP-2 activity and messenger RNA levels. Cycloheximide and actinomycin-D inhibited basal TIMP-1 and TIMP-2 activity and inhibited the ability of FSH, 8-bromo-cAMP, and TPA to stimulate TIMP activity. The protein kinase A (PKA) inhibitor AMP Rp isomer did not affect basal TIMP-1 and TIMP-2 activity or TPA-stimulated TIMP-1 activity. However, the PKA inhibitor markedly reduced FSH and 3-isobutyl-1-methylxanthine stimulation of TIMP-1 and TIMP-2 activity. FSH, 8-bromo-cAMP, and TPA stimuli induced DNA binding complexes capable of binding to a TIMP-1 AP-1 site consensus sequence oligonucleotide. The AP-1 site binding complex(es) induced by all three treatments reacted with antibodies directed broadly against fos and jun protooncogene families and against the specific family members c-fos, junB, and junD but not c-jun proteins. Constitutive cAMP response element binding activity capable of binding an artificial cAMP response element binding site oligonucleotide was demonstrated in Sertoli cell nuclear extracts. This activity was minimally modulated by FSH, 8-bromo-cAMP, or TPA treatment. In summary, Sertoli cells secrete TIMP-1 and TIMP-2 that can be coordinately up-regulated by FSH through a cAMP, PKA-dependent pathway. a convergence of TPA, FSH, and cAMP mediated signals in prepubertal Sertoli cells may occur with the induction of specific AP-1 site binding complex(es) containing jun and fos proteins. Our data suggest that FSH stimulation of TIMP-2 expression may be regulated independently to that of TIMP-1. We propose that the ability of FSH to stimulate Sertoli cell TIMP activity suggests a central role for this hormone in the control of extracellular matrix turnover during testicular development at the level of metalloproteinase inhibition.
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PMID:Follicle-stimulating hormone increases the expression of tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 and induces TIMP-1 AP-1 site binding complex(es) in prepubertal rat Sertoli cells. 798 35

The transcription control region of the proto-oncogene c-fos contains multiple cis-acting elements to which specific trans-acting factors bind. One such well-studied binding motif in the c-fos promoter is the major cyclic AMP response element (CRE) TGACGT located at -62/-57. In this study we investigated the role of this element in gene regulation by beta 2-adrenergic/adenylate cyclase signalling and DNA methylation. By transient gene expression assays we were able to show that the c-fos regulatory sequences spanning nucleotides -361 to +13 could mediate gene expression by the beta 2-adrenergic agonist isoproterenol and the phosphodiesterase inhibitor theophylline. For isoproterenol however, a stimulating effect was observed in serum-starved cells, while an inhibitory effect was measured in cells supplemented with serum. The gene regulation by the cAMP elevating agents could be due, at least partially, to the major CRE since this isolated motif mediated gene expression by these drugs. Distinct protein-DNA complexes were obtained with nuclear extracts prepared from cells exposed to isoproterenol or/and theophylline under different serum conditions. We further show that DNA methylation of this CRE may also be involved in gene regulation as methylation of the CRE motif strongly reduced the binding of nuclear proteins.
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PMID:The c-fos cAMP-response element: regulation of gene expression by a beta 2-adrenergic agonist, serum and DNA methylation. 809 31

Parathyroid hormone (PTH)-mediated gene activation was assessed in the osteoblast-like rat cell line ROS17/2.8 with two PTH fragments harboring distinct activating domains: PTH-(1-34) and PTH-(28-48). The PTH response of genes expressed immediate early in the cell cycle or in the osteoblast developmental sequence was investigated. In addition, subtractive cloning was used to identify genes in ROS17/2.8 cells that are activated by the two PTH domains. PTH-(1-34) immediately increased the transcript levels of c-fos and c-jun at a considerably higher rate than PTH-(28-48). A significant immediate PTH effect on osteoblastic marker genes could not be detected, with the exception of elevated ornithine decarboxylase transcript levels. However, continuous application of PTH-(1-34) increased transcript levels of the osteoblast-specific osteocalcin gene and reduced those of other osteoblastic marker genes including alkaline phosphatase and the PTH/PTH-related peptide receptor. By subtractive cloning, nine cDNAs were isolated corresponding to mRNAs directly up-regulated by PTH-(1-34) or PTH-(28-48). Among these were a cyclic phosphodiesterase, a (cytosine 5)-methyltransferase, an 80-kDa protein kinase C substrate, junB, and a novel GC-binding protein. Three cDNAs are unknown at present. Interestingly, in all cases, the efficiency of gene activation by PTH-(28-48) was substantially lower in comparison with PTH-(1-34). PTH-mediated protein kinase C signaling in ROS17/2.8 cells may therefore constitute a minor pathway in comparison with the dominant cAMP/protein kinase A cascade.
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PMID:Domain-specific gene activation by parathyroid hormone in osteoblastic ROS17/2.8 cells. 870 88

The non-competitive NMDA receptor antagonists, such as (+)-MK-801 (dizocilpine), cause the expression of heat shock protein HSP-70 and pathomorphological damage in the retrosplenial cortex of the rat brain. However, the precise mechanism(s) underlying the neurotoxicity of NMDA receptor antagonists is unknown. The present study was undertaken to examine the role of phosphodiesterase type IV in the expression of heat shock genes induced by dizocilpine. Heat shock protein HSP-70, which is known as a sensitive marker of neuron injury, was induced in the retrosplenial cortex of the rat brain 24 h after a single administration of dizocilpine (1 mg/kg). Pretreatment with the specific phosphodiesterase type IV inhibitor rolipram (2.5, 5 or 10 mg/kg, 15 min before dizocilpine) attenuated the expression of HSP-70 and hsp-70 mRNA induced by dizocilpine (1 mg/kg) in a dose-dependent manner. Furthermore, another phosphodiesterase type IV inhibitor, Ro 20-1724 (5 or 10 mg/kg, 15 min before dizocilpine), and a non-selective phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX) (5 or 10 mg/kg, 15 min before dizocilpine), significantly attenuated the expression of HSP-70 protein and hsp-70 mRNA induced in the retrosplenial cortex by dizocilpine. However, the induction of the immediate early gene c-fos and microglial activation in the retrosplenial cortex after administration of dizocilpine was not attenuated by pretreatment with rolipram (5 or 10 mg/kg, 15 min before dizocilpine). Moreover, histopathological study indicated that pretreatment with rolipram (5 or 10 mg/kg, 15 min before dizocilpine) did not prevent the formation of vacuoles caused by treatment with dizocilpine. The present findings suggest that phosphodiesterase type IV may play a significant role in the expression of HSP-70 protein and hsp-70 mRNA in the rat retrosplenial cortex after administration of dizocilpine, and that phosphodiesterase type IV may not play a role in the neurotoxicity of NMDA receptor antagonists such as dizocilpine.
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PMID:Rolipram, a selective phosphodiesterase type-IV inhibitor, prevents induction of heat shock protein HSP-70 and hsp-70 mRNA in rat retrosplenial cortex by the NMDA receptor antagonist dizocilpine. 938 12


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