scholarly journals Phosphorylation of Cyclic Adenosine Monophosphate Response Element Binding Protein in Oligodendrocytes in the Corpus Callosum after Focal Cerebral Ischemia in the Rat

2001 ◽  
Vol 21 (10) ◽  
pp. 1177-1188 ◽  
Author(s):  
Kortaro Tanaka ◽  
Shigeru Nogawa ◽  
Daisuke Ito ◽  
Shigeaki Suzuki ◽  
Tomohisa Dembo ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Corpus Callosum ◽  
Focal Cerebral Ischemia ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Medial Region ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
Phosphorylated Creb

Phosphorylation of cyclic adenosine monophosphate (AMP) response element binding protein (CREB) was examined immunohistochemically in the corpus callosum of the rat brain at various time points after 90-minute focal cerebral ischemia. Focal ischemia was induced by occlusion of the middle cerebral artery (MCA) using the intraluminal suture method. Sham animals showed that numerous oligodendrocytes (OLGs) constitutively express unphosphorylated CREB. Local cerebral blood flow (lCBF) measured by the14 C-iodoantipyrine method was reduced from 44.2 ± 15.4 (mL 100 g−1 min−1) to 18.4 ± 3.8 and from 53.9 ± 14.4 to 4.8 ± 4.5 in the medial and the lateral regions of the corpus callosum, respectively, during MCA occlusion (MCAO). After release of the MCAO, lCBF recovered to the control level in each region. The medial region of the corpus callosum showed a marked increase in phosphorylated CREB-positive OLGs at 3.5 hours of recirculation, and it remained increased until 2 weeks of recirculation as it gradually declined. The activation of CREB phosphorylation in the OLGs was accompanied by expression of antiapoptotic protein bcl-2, normal staining with cresyl violet, and negative TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling) staining. Myelination detected by immunostaining with anti-myelin basic protein (MBP) antibody and anti-myelin associated glycoprotein (MAG) antibody remained normal in the medial region of the corpus callosum. The lateral region of the corpus callosum showed a significant but only transient increase in phosphorylated CREB-positive OLGs at 3.5 hours of recirculation, which was followed by a rapid decrease during the subsequent recirculation period. Expression of bcl-2 was suppressed in this region, and demyelination became apparent. These findings suggest that signal transduction through CREB phosphorylation may be closely associated with survival of OLGs and maintenance of myelination in the corpus callosum after cerebral ischemia.

scholarly journals Cyclic AMP response element-binding protein is required in excitatory neurons in the forebrain to sustain wakefulness

SLEEP ◽  
2020 ◽  
Author(s):  
Mathieu E Wimmer ◽  
Rosa Cui ◽  
Jennifer M Blackwell ◽  
Ted Abel
Keyword(s):  
Cyclic Amp ◽  
Intracellular Signaling ◽  
Target Genes ◽  
Binding Protein ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
And Control

Abstract The molecular and intracellular signaling processes that control sleep and wake states remain largely unknown. A consistent observation is that the cyclic adenosine monophosphate (AMP) response element-binding protein (CREB), an activity-dependent transcription factor, is differentially activated during sleep and wakefulness. CREB is phosphorylated by the cyclic AMP/protein kinase A (cAMP/PKA) signaling pathway as well as other kinases, and phosphorylated CREB promotes the transcription of target genes. Genetic studies in flies and mice suggest that CREB signaling influences sleep/wake states by promoting and stabilizing wakefulness. However, it remains unclear where in the brain CREB is required to drive wakefulness. In rats, CREB phosphorylation increases in the cerebral cortex during wakefulness and decreases during sleep, but it is not known if this change is functionally relevant to the maintenance of wakefulness. Here, we used the Cre/lox system to conditionally delete CREB in the forebrain (FB) and in the locus coeruleus (LC), two regions known to be important for the production of arousal and wakefulness. We used polysomnography to measure sleep/wake levels and sleep architecture in conditional CREB mutant mice and control littermates. We found that FB-specific deletion of CREB decreased wakefulness and increased non-rapid eye movement sleep. Mice lacking CREB in the FB were unable to sustain normal periods of wakefulness. On the other hand, deletion of CREB from LC neurons did not change sleep/wake levels or sleep/wake architecture. Taken together, these results suggest that CREB is required in neurons within the FB but not in the LC to promote and stabilize wakefulness.

scholarly journals A Novel Cell-Based Assay for G-Protein-Coupled Receptor-Mediated Cyclic Adenosine Monophosphate Response Element Binding Protein Phosphorylation

2006 ◽  
Vol 11 (4) ◽  
pp. 351-358 ◽  
Author(s):  
Julie V. Selkirk ◽  
Lisa M. Nottebaum ◽  
Ian C. Ford ◽  
Mark Santos ◽  
Siobhan Malany ◽  
...  
Keyword(s):  
G Protein ◽  
Binding Protein ◽  
Expression System ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
G Protein Coupled Receptor ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
G Protein Coupled

Currently, the most popular means of assessing functional activity of Gs/olf-coupled receptors is via the measurement of intracellular cyclic adenosine monophosphate (cAMP) accumulation. An additional readout is the downstream phosphorylation of cAMP response element binding protein (CREB), which gives an indication of gene transcription, the ultimate response of many G-protein-coupled receptor (GPCR) signals. Current methods of quantifying CREB phosphorylation are low throughput, and so we have designed a novel higher throughput method using the Odyssey™ infrared imaging system. Functional potencies of both agonists and antagonists correlate well with radioligand binding affinities determined using examples of both an endogenous (adenosine2A receptor in PC-12 cells) and a heterologous (human melanocortin 4 receptor in HEK-293 cells) expression system. For example, the antagonist ZM241385 demonstrates 0.23 ± 0.03 nM affinity for the A2A receptor and has a functional potency of 0.26 ± 0.04 nM determined using cAMP and 0.15 ± 0.06 nM using CREB phosphorylation. These data demonstrate that this novel approach for the measurement of CREB phosphorylation is a useful tool for the assessment of GPCR activity in whole cells and is more amenable to the throughput required for the purposes of drug discovery.

Ceramide and Cyclic Adenosine Monophosphate (cAMP) Induce cAMP Response Element Binding Protein Phosphorylation via Distinct Signaling Pathways While Having Opposite Effects on Myeloid Cell Survival

Blood ◽  
1999 ◽  
Vol 93 (1) ◽  
pp. 217-225 ◽  
Author(s):  
Michael P. Scheid ◽  
Ian N. Foltz ◽  
Peter R. Young ◽  
John W. Schrader ◽  
Vincent Duronio
Keyword(s):  
P38 Mapk ◽  
Binding Protein ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Camp Response Element Binding ◽  
Camp Response Element ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
Induced Apoptosis

Abstract The role of ceramide as a second messenger is a subject of great interest, particularly since it is implicated in signaling in response to inflammatory cytokines. Ceramide induces apoptosis in both cytokine-dependent MC/9 cells and factor-independent U937 cells. Elevation of cyclic adenosine monophosphate (cAMP) levels inhibits apoptosis induced by ceramide and several other treatments. One target of cAMP-mediated signaling is the transcription factor CREB (cAMP response element binding protein), and recently CREB phosphorylation at an activating site has been shown to also be mediated by a cascade involving p38 mitogen-activated protein kinase (MAPK), one of the stress-activated MAP kinases. Because no role for p38 MAPK in apoptosis has been firmly established, we examined the relationship between p38 MAPK and CREB phosphorylation under various conditions. Ceramide, or sphingomyelinase, like tumor necrosis factor- (TNF-) or the hematopoietic growth factor, interleukin-3 (IL-3), was shown to activate p38 MAPK, which in turn activated MAPKAP kinase-2. Each of these treatments led to phosphorylation of CREB (and the related factor ATF-1). A selective p38 MAPK inhibitor, SB203580, blocked TNF-– or ceramide-induced CREB phosphorylation, but had no effect on the induction of apoptosis mediated by these agents. The protective agents cAMP and IL-3 also led to CREB phosphorylation, but this effect was independent of p38 MAPK, even though IL-3 was shown to activate both p38 MAPK and MAPKAP kinase-2. Therefore, the opposing effects on apoptosis observed with cAMP and IL-3, compared with ceramide and TNF-, could not be explained on the basis of phosphorylation of CREB. In addition, because SB203580 had no effect of TNF- or ceramide-induced apoptosis, our results strongly argue against a role for p38 MAPK in the induction of TNF-– or ceramide-induced apoptosis.

Ceramide and Cyclic Adenosine Monophosphate (cAMP) Induce cAMP Response Element Binding Protein Phosphorylation via Distinct Signaling Pathways While Having Opposite Effects on Myeloid Cell Survival

Blood ◽  
1999 ◽  
Vol 93 (1) ◽  
pp. 217-225 ◽  
Author(s):  
Michael P. Scheid ◽  
Ian N. Foltz ◽  
Peter R. Young ◽  
John W. Schrader ◽  
Vincent Duronio
Keyword(s):  
P38 Mapk ◽  
Binding Protein ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Camp Response Element Binding ◽  
Camp Response Element ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
Induced Apoptosis

The role of ceramide as a second messenger is a subject of great interest, particularly since it is implicated in signaling in response to inflammatory cytokines. Ceramide induces apoptosis in both cytokine-dependent MC/9 cells and factor-independent U937 cells. Elevation of cyclic adenosine monophosphate (cAMP) levels inhibits apoptosis induced by ceramide and several other treatments. One target of cAMP-mediated signaling is the transcription factor CREB (cAMP response element binding protein), and recently CREB phosphorylation at an activating site has been shown to also be mediated by a cascade involving p38 mitogen-activated protein kinase (MAPK), one of the stress-activated MAP kinases. Because no role for p38 MAPK in apoptosis has been firmly established, we examined the relationship between p38 MAPK and CREB phosphorylation under various conditions. Ceramide, or sphingomyelinase, like tumor necrosis factor- (TNF-) or the hematopoietic growth factor, interleukin-3 (IL-3), was shown to activate p38 MAPK, which in turn activated MAPKAP kinase-2. Each of these treatments led to phosphorylation of CREB (and the related factor ATF-1). A selective p38 MAPK inhibitor, SB203580, blocked TNF-– or ceramide-induced CREB phosphorylation, but had no effect on the induction of apoptosis mediated by these agents. The protective agents cAMP and IL-3 also led to CREB phosphorylation, but this effect was independent of p38 MAPK, even though IL-3 was shown to activate both p38 MAPK and MAPKAP kinase-2. Therefore, the opposing effects on apoptosis observed with cAMP and IL-3, compared with ceramide and TNF-, could not be explained on the basis of phosphorylation of CREB. In addition, because SB203580 had no effect of TNF- or ceramide-induced apoptosis, our results strongly argue against a role for p38 MAPK in the induction of TNF-– or ceramide-induced apoptosis.

scholarly journals Estradiol Suppresses Phosphorylation of Cyclic Adenosine 3′,5′-Monophosphate Response Element Binding Protein (CREB) in the Pituitary: Evidence for Indirect Action via Gonadotropin-Releasing Hormone

1999 ◽  
Vol 13 (8) ◽  
pp. 1338-1352
Author(s):  
W. Rachel Duan ◽  
Jennifer L. Shin ◽  
J. Larry Jameson
Keyword(s):  
Gene Promoter ◽  
Camp Response Element Binding ◽  
Ovariectomized Rats ◽  
Pituitary Cells ◽  
Camp Response Element ◽  
Similar Reduction ◽  
Response Element ◽  
Creb Phosphorylation ◽  
Element Binding Protein ◽  
Phosphorylated Creb

Abstract Estradiol acts on the hypothalamus and pituitary gland to modulate the synthesis and secretion of gonadotropins. We recently reported that GnRH-induced transcription of the human gonadotropin α-gene promoter is increased markedly in transfected pituitary cells derived from animals treated with estradiol. Because the cAMP response element binding (CREB) protein plays an important role in the transcriptional regulation of this promoter and is highly regulated by posttranslational phosphorylation, we hypothesized that it might serve as a target for estradiol-induced sensitivity to GnRH. In this study, we assessed the roles of estradiol and GnRH in the regulation of CREB phosphorylation in the rat pituitary. Using an antibody that specifically recognizes phosphorylated CREB (pCREB), we found that the pituitary content of pCREB was inversely related to the level of estradiol during the estrous cycle. Ovariectomy increased the level of pCREB, and treatment with estradiol for 10 days decreased the content of pCREB dramatically (93% inhibition). A similar reduction of pCREB was seen when ovariectomized rats were treated with a GnRH receptor antagonist for 10 days. This result indicates that the ovariectomy-induced increase in pCREB is GnRH-dependent. In αT3 gonadotrope cells, estradiol had no direct effect on CREB phosphorylation, whereas GnRH increased CREB phosphorylation 4- to 5-fold within 5 min. We conclude that estradiol inhibits CREB phosphorylation in the gonadotrope, probably by inhibiting GnRH production. The estradiol-induced decrease in CREB phosphorylation is proposed to lower basalα -promoter activity and increase its responsiveness to GnRH. (Molecular Endocrinology 13: 1338–1352, 1999)

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