Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.10.2 (
focal adhesion kinase
)
44,029
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The differential regulation of immunoactive
FSH
and LH secretion by endogenous GnRH was studied using a GnRH antagonist, [Ac-D2Nal1,D4FPhe2,DTrp3,DArg6]GnRH (the NAL-
ARG
antagonist), in normal women in the early follicular phase of the menstrual cycle, and their responses were compared to those in two groups of control women. Pulsatile LH secretion was examined as an index of the completeness of blockade of endogenous GnRH secretion. There was a dose-dependent decrease in both the frequency and amplitude of LH pulses. At the highest dose, LH pulses were completely abolished within 20 min after sc administration of the GnRH antagonist and for a minimum of 8 h in all women. The mean plasma LH levels were reduced within the first 4 h after antagonist administration at all doses (P less than 0.001). The duration of LH suppression was influenced by antagonist dose, with a continued effect 24 h after administration of the 500 micrograms/kg dose only. The maximum degree of LH suppression was 40% after 50 micrograms/kg (n = 6), 60% after 150 micrograms/kg (n = 6), and 59% after 500 micrograms/kg (n = 5). In contrast, plasma immunoreactive
FSH
levels did not change after these doses of the NAL-
ARG
GnRH antagonist. The maximum degree of
FSH
suppression was 16%, and the changes in plasma
FSH
concentrations were not dose dependent. Serum antagonist concentrations rose within 30 min after its administration to mean peak levels of 7.5 +/- 2.1 (+/- SE), 20.4 +/- 6.1, and 151 +/- 21 ng/mL after the 50, 150, and 500 micrograms/kg doses, respectively. The half-time of the disappearance of the NAL-
ARG
GnRH antagonist from plasma was 8.8 +/- 1.5 h. While there were no effects of antagonist administration on hematological, hepatic, or renal function, three women developed urticaria distant from the site of injection when administered the highest dose. We conclude that blockade of GnRH receptors by a GnRH antagonist 1) effectively antagonizes the action of GnRH, as assessed by its ability to block pulsatile LH secretion and reduce mean plasma LH levels; and 2) inhibits LH release to a considerably greater degree than
FSH
release, providing further evidence of possible GnRH-independent
FSH
secretion.
...
PMID:Evidence of differential control of FSH and LH secretion by gonadotropin-releasing hormone (GnRH) from the use of a GnRH antagonist. 313 43
The aim of this study was to investigate whether the stimulatory effect of growth hormone (GH) on the in vitro maturation and cumulus expansion of bovine oocytes is exerted through the cAMP or the tyrosine kinase pathway. Therefore bovine cumulus-oocyte complexes (COCs) were cultured in Medium 199 without fetal calf serum and gonadotropins, but supplemented with 100 ng/ml bovine GH (bGH; NIH-GH-B18) with or without 10 microM methyl 2,5-dihydroxycinnamate (erbstatin analogue), a specific tyrosine kinase inhibitor; 100 microM 2',3'-dideoxyadenosine (DDA), a specific adenylate cyclase inhibitor; or 10 microM H-89, a specific inhibitor of cAMP-dependent protein kinase A. Epidermal growth factor (EGF; 20 ng/ml) was added as a positive control for tyrosine kinase activation, and
FSH
(0.05 IU/ml) was added as a positive control for cAMP mediation during in vitro maturation in the absence or presence of the inhibitors. Culture was performed at 39 degrees C in a humidified atmosphere with 5% CO2 in air. To assess the effect on nuclear maturation, the proportion of oocytes in metaphase II stage after 16 h of culture was determined using 4,6-diamino-2-phenylindole staining. To determine the effect on cumulus expansion, the diameter of COCs at the onset and after 24 h of culture was measured. The stimulatory effects of GH on oocyte maturation and cumulus expansion were blocked by DDA and H-89 (p < 0.01). Similarly,
FSH
-induced cumulus expansion was abolished by DDA and H-89 (p < 0.05), while DDA did not block either EGF-induced oocyte maturation or cumulus expansion. Erbstatin analogue significantly blocked the stimulation of oocyte maturation and cumulus expansion by EGF (p < 0.02) but did not inhibit GH action on the COCs. It is concluded that the stimulatory effect of GH on oocyte maturation and cumulus expansion is mediated by the cAMP signal transduction pathway and not by
JAK2
phosphorylation.
...
PMID:Stimulatory effect of growth hormone on in vitro maturation of bovine oocytes is exerted through the cyclic adenosine 3',5'-monophosphate signaling pathway. 940 58
We report on a patient with Klinefelter's syndrome who underwent successful syngeneic peripheral blood stem cell transplantation (PBSCT) for chronic myelogenous leukemia (CML). A-46-year-old man was given a diagnosis of chronic phase CML in May 1994 on the basis of findings of leukocytosis (54,000/microliter) and bone marrow chromosomal abnormalities [47, XXY, t(9; 22; 14) (q34; q11; q24)]. Hydroxyurea and interferon alpha were administered. In August 1996, a syngeneic transplant was performed following myeloablative therapy, using peripheral blood stem cells collected from the patient's identical twin brother, who had been pretreated with rhG-CSF. Following transplantation (4.0 x 10(6) CD34+ cells/kg) and the subsequent administration of rhG-CSF, the patient rapidly achieved normal tri-lineage hematopoiesis. A post-transplant chromosomal analysis of the patient's bone marrow cells detected the 47, XXY karyotype. Although the major BCR-
ABL
gene had been detected in bone marrow by RT-PCR methods prior to the syngeneic PBSCT (August 1996), it was not detected after PBSCT (January 1997). In March 1998, interphase fluorescence in situ hibridization (FISH) procedures disclosed XXY signal patterns in peripheral blood lymphocyte samples from the patient and donor, at frequencies of 96% and 97%, respectively. Both the patient and donor had high levels of serum
FSH
and LH and low levels of serum testosterone.
...
PMID:[Syngeneic peripheral blood stem cell transplantation for chronic myelogenous leukemia associated with Klinefelter's syndrome]. 1022 29
FSH
stimulates in ovarian granulosa cells diverse, differentiation-dependent responses that implicate activation of specific cellular signaling cascades. In these studies three kinases were investigated to determine their relationship to
FSH
, cAMP, and A kinase signaling: protein kinase B (
PKB
/Akt), serum and glucocorticoid-induced kinase (Sgk), and p38 mitogen-activated protein kinase (p38MAPK). The phosphorylation (activation) of these kinases was analyzed by using selective agonists/inhibitors: forskolin/H89 for cAMP-dependent protein kinase (A kinase), insulin-like growth factor I (IGF-I)/LY294002 and wortmannin for phosphatidylinositol-dependent kinase (PI3-K), and phorbol myristate (PMA)/GF109203X for diacylglycerol and Ca++-dependent kinases (C kinases). An inhibitor (PD98059) of MEK1, which regulates extracellular regulated kinases (ERKs), and SB203580, which inhibits p38MAPK, were also used. In addition, we analyzed the expression of the recently described, cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFI and GEFII) that impact Ras-related GTPases and Raf kinases, known regulators of various protein kinase cascades. We provide evidence that
FSH
, forskolin, and 8-bromo-cAMP stimulate phosphorylation of
PKB
by mechanisms involving PI3-K (LY294002/wortmannin sensitive) not A kinase (H89 insensitive), a pattern of response mimicking that of IGF-I. In contrast,
FSH
induction and phosphorylation of Sgk protein requires A kinase (H89 sensitive) but also involves PI3-K (LY294002 sensitive) as well as p38MAPK (SB203580 sensitive) pathways. PMA (C kinase) abolished
FSH
-mediated (but not IGF-I-mediated) phosphorylation of
PKB
at a step(s) upstream of PI3-K and independent of A kinase. Lastly,
FSH
-mediated phosphorylation of p38MAPK is negatively affected by A kinase and PI3-K, suggesting that it may be downstream of specific members of the cAMP-GEF/Rap/Raf pathway. We propose that cAMP activation of A kinase is obligatory for transcription of Sgk in granulosa cells whereas cAMP (IGF-I-like)-mediated phosphorylation (activation) of
PKB
and Sgk (via PI3-K), as well as p38MAPK, involves other cellular events. These results provide new and exciting evidence that cAMP acts in granulosa cells by A kinase-dependent and -independent mechanisms, each of which controls specific kinase cascades.
...
PMID:Follicle-Stimulating hormone (FSH) stimulates phosphorylation and activation of protein kinase B (PKB/Akt) and serum and glucocorticoid-lnduced kinase (Sgk): evidence for A kinase-independent signaling by FSH in granulosa cells. 1093 51
The glycoprotein hormones, ACTH, TSH,
FSH
, and LH regulate diverse functions in endocrine cells. Although cAMP and PKA have long been shown to mediate specific intracellular signaling events including the transcription of specific genes via the CREB-CBP complex, recent observations have indicated that PKA does not account for all of the intracellular targets of cAMP. For example, TSH stimulation of thyroid cell proliferation is not completely blocked by PKA inhibitors. TSH and
FSH
can stimulate
PKB
phosphorylation by a PKAindependent but PI3-K/PDK1-dependent pathway. An
FSH
inducible kinase, Sgk, has recently been shown to be a close relative of
PKB
. Sgk is also a target of PI3-K-PDK1 pathway, indicating that some effects previously ascribed to
PKB
may be mediated by this inducible kinase. The identification of novel cAMP-binding proteins that exhibit guanine nucleotide exchange (GEF) activity (cAMP-GEFS; Epacs) has open new doors for cAMP action that include activation of small GTPases such as Rap1a, Rap2, and possibly Ras. These GTPases are known activators of downstream kinase cascades, including p38MAPK and Erk1/2 as well as PI3-K. Thus,
FSH
and TSH activation of
PKB
and Sgk may occur via this alternative cAMP pathway that involves cAMP-GEFs and the activation of the PI3-K/PDK1 pathway.
...
PMID:New signaling pathways for hormones and cyclic adenosine 3',5'-monophosphate action in endocrine cells. 1115 28
The gonadotropin
FSH
plays a key role in the control of Sertoli cell function. The
FSH
molecular mechanism of action is best recognized for its stimulation of the adenylyl cyclase/cAMP pathway. However, other signaling events have also been demonstrated in Sertoli cells. We have recently presented evidence that
FSH
can stimulate the phosphatidylinositol 3-kinase/protein kinase B (PI3K/
PKB
) pathway in 20-day-old Sertoli cells. At the same time, it was proposed that in 8-day-old Sertoli cells the effects of
FSH
on phosphorylated
PKB
(P-PKB) levels can be explained by a combination of increased secretion of endogenous IGF-I, decreased IGF-binding protein-3 (IGFBP-3) production, and a synergistic action of
FSH
on IGF-I-dependent PI3K activation. The aim of the present study was to determine whether the effect of
FSH
on 20-day-old Sertoli cells is mediated by IGF-I secretion. Twenty-day-old rat Sertoli cell cultures were used.
FSH
stimulation produced a time-dependent increment in P-
PKB
levels reaching maximal values in 60-min incubations. IGF-I stimulation was also time-dependent reaching maximal values in 15-min incubations. On the other hand, stimulation of the cultures with
FSH
showed time-dependent inhibition in phosphorylated mitogen-activated protein kinase (P-MAPK) levels. In sharp contrast, stimulation of the cultures with IGF-I showed time-dependent increments in P-MAPK levels reaching maximal stimulus in 15-min incubations. In order to rule out an IGF-I action on
FSH
stimulation of P-
PKB
levels, the effect of a specific IGF-I antibody on the ability of both hormones to increase P-
PKB
levels was evaluated. As expected, the antibody inhibited IGF-I stimulation of P-
PKB
levels. However, simultaneous addition of an IGF-I antibody with
FSH
did not modify the ability of the hormone to increase P-
PKB
levels. The next set of experiments intended to analyze the relevance of a PI3K/
PKB
pathway to two biological responses of Sertoli cells to
FSH
and IGF-I. The PI3K inhibitor, wortmannin, dose-dependently decreased
FSH
-stimulated lactate and transferrin production. On the other hand, wortmannin was not able to modify the ability of IGF-I to stimulate these metabolic events. In addition, the analysis of the participation of a MAPK pathway in IGF-I regulation of Sertoli cell biological responses showed that the MAPK kinase inhibitors, PD98059 and U0126, decreased IGF-I-stimulated transferrin secretion while not modifying IGF-I-stimulated lactate levels. In summary, results obtained so far support the hypothesis that
FSH
action on P-
PKB
levels and Sertoli cell metabolism in 20-day-old animals is not mediated by autocrine regulation of an IGF-I/ IGFBP-3 axis as previously proposed in 8-day-old Sertoli cells.
...
PMID:FSH activates phosphatidylinositol 3-kinase/protein kinase B signaling pathway in 20-day-old Sertoli cells independently of IGF-I. 1476 77
Inactivation of the cyclic nucleotide signal in granulosa cells depends on a complex array of cyclic nucleotide phosphodiesterases (PDE). In order to examine the role of PDE in cyclic AMP (cAMP) signaling in granulosa cells, the present study examined the expression of PDE4D proteins and regulation of cAMP-PDE activities in cultured rat granulosa cells. The results of immunoblot analyses showed that two predominant PDE4D subtypes of approximately 80 and 70 kDa appeared when immature rat granulosa cells were treated with
FSH
. However, these two new subtypes presumed to be PDE4D proteins were not influenced by treatments of DETA/NO, cGMP and
PKB
inhibitor, LY294002. Immature rat granulosa cells treated with medium alone displayed low cAMP-PDE activity throughout 48 h of culture while those treated with
FSH
(2 ng.mL-1) showed a marked increase in cAMP-PDE activity between 6 and 12 h of culture, followed by a decline. The findings from the present study indicate that the increased cAMP-PDE activity by
FSH
is mainly related to the changes of PDE4D protein levels. However, the inhibitory effects of NO on cAMP accumulation in rat granulosa cells are not via the increased cAMP-PDE activity.
...
PMID:Role of phosphodiesterase in cyclic AMP signaling in cultured rat granulosa cells. 1682 53
Spermiation is the final step of spermatogenesis and culminates in the disengagement (release) of elongated spermatids from Sertoli cells into the seminiferous tubule lumen. Spermiation failure, wherein spermatids are retained by Sertoli cells instead of releasing, occurs after hormone suppression. The mechanisms involved in spermatid disengagement and retention are not well understood. We previously showed that beta(1)-integrin is associated with spermatids until the point of disengagement, but the ectoplasmic specialisation junction (ES) is not. The aims of this paper are to further characterise the complex that is present immediately prior to spermatid disengagement by identifying the alpha-integrin form dimerised with beta(1)-integrin, localising
focal adhesion kinase
(
FAK
) and determining if microtubules are involved. Adult Sprague-Dawley rats received testosterone and oestradiol implants and an
FSH
antibody for 7 days to suppress testicular testosterone and
FSH
and induce spermiation failure. Control rats were treated with saline. Immunohistochemical analysis showed that alpha(6)-integrin and a phosphorylated form of
FAK
(
FAK
-Tyr(397)) are present between late spermatids and Sertoli cells after ES removal, until the point of disengagement, and both proteins remain associated with retained spermatids after spermiation failure induced by hormone suppression. Using dual-label immunofluorescence, tubulins (and thus microtubules) were observed to co-localise with ES, but were neither associated with elongated spermatids just prior to release nor with retained spermatids following hormone suppression. These results suggest that microtubules are not involved in the final release of spermatids from Sertoli cells. We conclude that spermatid release during spermiation is mediated by a 'disengagement complex' containing alpha(6)beta(1)-integrin and phospho-
FAK
, the function of which can be affected by gonadotrophin suppression.
...
PMID:A complex containing alpha6beta1-integrin and phosphorylated focal adhesion kinase between Sertoli cells and elongated spermatids during spermatid release from the seminiferous epithelium. 1700 77
FSH
regulates ovarian granulosa cell differentiation not only by activating adenylyl cyclase and protein kinase A (PKA) but also by other complex mechanisms. Using primary rat granulosa cell cultures, we provide novel evidence that
FSH
rapidly activates two small GTP-binding proteins RAP1 and RAS.
FSH
activation of RAP1 requires cAMP-mediated activation of exchange factor activated by cAMP/RAPGEF3 whereas
FSH
activation of RAS and downstream signaling cascades involves multiple factors. Specifically,
FSH
activation of RAS required Rous sarcoma oncogene (SRC) family tyrosine kinase (SFK) and epidermal growth factor receptor (EGFR) tyrosine kinase activities but not PKA.
FSH
-induced phosphorylation of ERK1/2 was blocked by dominant-negative RAS as well as by inhibitors of EGFR tyrosine kinase, metalloproteinases involved in growth factor shedding, and SFKs. In contrast,
FSH
-induced phosphorylation of protein kinase B (
PKB
/AKT) and the Forkhead transcription factor, FOXO1a occurred by SFK-dependent but RAS-independent mechanisms. The SFKs, c-SRC and
FYN
, and the SRC-related tyrosine kinase
ABL
were present and phosphorylated rapidly in response to
FSH
. Lastly, the EGF-like factor amphiregulin (AREG) activated RAS and ERK1/2 phosphorylation in granulosa cells by mechanisms that were selectively blocked by an EGFR antagonist but not by an SFK antagonist. However, AREG-mediated phosphorylation of
PKB
and FOXO1a required both EGFR and SFK activation. Moreover, we show that
FSH
induces AREG and that activation of the EGFR impacts granulosa cell differentiation and the expression of genes characteristic of the luteal cell phenotype. Thus,
FSH
orchestrates the coordinate activation of three diverse membrane-associated signaling cascades (adenylyl cyclase, RAS, and SFKs) that converge downstream to activate specific kinases (PKA, ERK1/2, and
PKB
/FOXO1a) that control granulosa cell function and differentiation.
...
PMID:Follicle-stimulating hormone induces multiple signaling cascades: evidence that activation of Rous sarcoma oncogene, RAS, and the epidermal growth factor receptor are critical for granulosa cell differentiation. 1753 7
Traumatic brain injury (TBI) is the leading cause of death and disability in young adults. Growth hormone-insulin-like growth factor I (GH-IGF-I) system has an important role in the recovery of the central nervous system. The aim of the study was to evaluate the relationship between pituitary function (in particular, the GH-IGF-I axis) and outcome from TBI. We studied 72 patients (56 males; mean age 37.2 +/- 1.8 years) receiving rehabilitation after TBI. According to the Glasgow Coma Scale (GCS), 10 patients had moderate and 52 severe TBI. Ten patients had growth hormone GH deficiency (GHD), 10 LH-
FSH
, three TSH, and three ACTH deficiency. Overall pituitary dysfunction occurred in 22 (30.5%) patients, with anterior hypopituitarism in 19 (26.4%), isolated diabetes insipidus in one, and isolated hyperprolactinemia in two. GH response to GHRH +
ARG
(arginine) positively correlated with Functional Independence Measure (FIM D; r = 0.267, p < 0.02) and Level of Cognitive Functioning Scale (LCFS D; r = 0.287, p < 0.01) at discharge, and negatively with Disability Rating Score at discharge (DRS D; r = -0.324, p < 0.005). Unfavorable outcome measures (FIM D, LCFS D, and DRS D) occurred in patients with hypopituitarism as compared with normal pituitary function (p < 0.05). Multiple regression analysis identified both GCS (p < 0.005) and GH peak (p < 0.05) as strong independent predictors of outcome. In conclusion, recovery after TBI may be negatively influenced by concomitant pituitary dysfunction. The GH peak value is an independent predictor of outcome, indicating that recovery during an intensive rehabilitation program after TBI may be positively influenced by normal GH secretion.
...
PMID:Anterior pituitary function may predict functional and cognitive outcome in patients with traumatic brain injury undergoing rehabilitation. 1800 Nov 99
1
2
Next >>