Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This investigation determined the effects of K(+) channel antagonists on proliferation, differentiation, and apoptosis of porcine granulosa cells. The drugs screened for functional effects included the class III antiarrhythmic agents MK-499 and clofilium, the chromanol I(Ks) antagonist 293B, the benzodiazepine I(Ks) antagonists L-735,821 and L-768,673, and the peptidyl toxins charybdotoxin (CTX) and margatoxin (MTX). Granulosa cell proliferation and differentiation were assessed by serial measurements of cell number and progesterone accumulation in the culture media, respectively. Granulosa cell apoptosis was evaluated using flow cytometry. Additional information about drug effects was obtained by immunoblotting to detect expression of proliferating cell nuclear antigen, p27(kip1) and the caspase-3 substrate poly(ADP-ribose) polymerase. The ERG channel antagonist MK-499 had no functional effects on cultured granulosa cells. However, the broad spectrum K(+) channel antagonist clofilium decreased, in a concentration-dependent fashion, the number of viable granulosa cells cultured, and these effects were associated with induction of apoptosis. All three I(Ks) antagonists (293B, L-735,821, and L-768,673) increased basal, but not FSH-enhanced progesterone accumulation on Day 1 after treatment without affecting the number of viable cells in culture, an effect that was blocked by pimozide. In contrast, CTX and MTX increased the number of viable cells in FSH-stimulated cultures on Day 3 after treatment without affecting progesterone output per cell. These data demonstrate that selective antagonism of granulosa cell K(+) channels with distinct molecular correlates, electrophysiological properties, and expression patterns can influence differential granulosa cell proliferation, steroidogenic capability, and apoptosis. Thus, K(+) channels may represent pharmacological targets for affecting Granulosa cell function and oocyte maturation, in vivo or in vitro.
 ...
PMID:Potassium channel antagonists influence porcine granulosa cell proliferation, differentiation, and apoptosis. 1208 3

Hyperandrogenism is known to perturb ovarian physiology resulting in anovulatory conditions. In the ovary, androgens produced by theca-interstitial cells are converted to estrogens in granulosa cells under the influence of FSH and LH. In some of the target organs, including the ovary, androgens are also converted into their 5alpha reduced metabolites. In the present study, we examined the molecular mechanism by which dihydrotestosterone (DHT), a 5alpha reduced metabolite of testosterone, mediates the inhibition of granulosa cell proliferation, using a rat model. Immature female rats were primed with estradiol, followed by DHT administration for 2 d and granulosa cells were cultured in the presence or absence of forskolin. Granulosa cells from the DHT-treated rats showed reduced [(3)H]thymidine incorporation into DNA and reduced cell number in response to forskolin stimulation, compared with control. The decreased responsiveness of DHT-treated granulosa cells to forskolin was not due to increased apoptosis because the expression of cleaved caspase 3 remained the same in both control and DHT-exposed granulosa cells stimulated with forskolin. Forskolin treatment stimulated the expression of cyclin D2 mRNA in control granulosa cells, whereas DHT treatment abolished this response. In vitro DHT treatment of granulosa cells for 48 h resulted in a cell cycle arrest with 70% of cells at G1 phase and 26% at S phase, and control cells exhibited a distribution of 42% and 55% at G1 and S phase, respectively. In conclusion, the present study shows that DHT inhibits the granulosa cell proliferation through a decrease in cyclin D2 mRNA expression, which leads to cell cycle arrest at the G1 phase.
 ...
PMID:Dihydrotestosterone inhibits granulosa cell proliferation by decreasing the cyclin D2 mRNA expression and cell cycle arrest at G1 phase. 1213 May 58

Apoptosis is necessary for the development and maturation of Leydig cells. However, increased apoptosis results the decline of testosterone production, which may increase germ cell apoptosis and the possibility of infertility. There are several aspects contributing to Leydig cell apoptosis such as ethane dimethanesulphonate (EDS), glucocorticoid, developmental stage and some hormones including FSH, LH/hCG and testosterone. A number of genes are involved in the regulation of Leydig cells apoptosis. It was reported that SCF/c-kit, Bcl-2 and Bcl-xl inhibited the apoptosis while caspase-3, Fas, Bax and clusterine stimulated it.
 ...
PMID:[Leydig cell apoptosis and its regulation]. 1286 41

In this study, we investigated the mechanisms of protein kinase B (PKB) activation and its role in cumulus cells during in vitro meiotic resumption of porcine oocytes. PKB activity in cumulus cells was significantly decreased by 12 h cultivation of cumulus-oocyte complexes (COCs) in basic medium. However, the addition of phosphodiesterase inhibitors, hypoxanthine or 3-isobutyl-1-methylxanthine, maintained the level of PKB activity in cumulus cells at comparable with that in cumulus cells just after collection from their follicles. When COCs were cultured with phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor, LY294002, PKB activity was significantly decreased, and both caspase 3 activity and the proportion of apoptotic cells were significantly increased as compared with those in cumulus cells just after collection from their follicles. Moreover, the inhibitory effect of hypoxanthine on spontaneous meiotic resumption was overcome by addition of LY294002. On the other hand, markedly high activity of PKB and high intensity of the phosphorylated PKB band were observed in cumulus cells of COCs which were cultured with FSH. The addition of 20 microM LY294002 to FSH-containing medium induced an apoptosis of cumulus cells, whereas little apoptotic-positive signal was detected in COCs cultured with 5 microM LY294002 and FSH. However, the inhibitory effects of LY294002 on progesterone production by cumulus cells and germinal vesicle breakdown in oocytes reached a maximum at 5 microM. Thus, high activity of the PI 3-kinase-PKB pathway in cumulus cells plays an important role in FSH regulation of cell function. Judging from these results, it is estimated that PI 3-kinase in cumulus cells is required for both the suppression of spontaneous meiotic resumption and the induction of gonadotropin-stimulated meiotic resumption.
 ...
PMID:Phosphatidylinositol 3-kinase in cumulus cells is responsible for both suppression of spontaneous maturation and induction of gonadotropin-stimulated maturation of porcine oocytes. 1452 62

Apoptosis causes the elimination of ovarian germ cells and the atretic degeneration of ovarian follicles. Here we have used cultured rat preovulatory follicles to examine the regulation of effector caspase-3 and -7 in follicles undergoing apoptosis in the presence or absence of gonadotropins or IGF-I. Culturing follicles in the presence or absence of serum resulted in the induction of apoptosis of granulosa cells (GC), which was accompanied by effector caspase activation. Surprisingly, the addition of the survival factors LH or FSH, but not IGF-I, further increased caspase-3 and -7 activity. Immunohistochemistry studies of the LH- and FSH-treated follicles indicated that cleaved caspase-3 was predominantly localized to the peripheral theca-interstitial cells (TIC). Western blot analysis and caspase-3 and -7 activity assays of the separated follicular compartments confirmed that both LH and FSH treatments significantly enhance caspase-3 and -7 activity in TIC. The elevation in caspase-3 and -7 activity in TIC was accompanied by an increase in apoptosis. Interestingly, LH and FSH also induced an increase in caspase-3 and -7 activity in GC; however, this increase was accompanied by a decrease in apoptosis. Finally, we demonstrate that in freshly isolated preovulatory follicles and in antral follicles in intact ovaries, the expression level of procaspase-3 is significantly higher in TIC than in GC. Thus, LH and FSH have a dual effect on the cultured rat preovulatory follicle: an antiapoptotic effect on GC and a proapoptotic effect on TIC.
 ...
PMID:Gonadotropins enhance caspase-3 and -7 activity and apoptosis in the theca-interstitial cells of rat preovulatory follicles in culture. 1472 42

To investigate the effect of thyroid hormone on the proliferative activity and apoptosis of granulosa cells at the varying stages of follicular growth, porcine granulosa cells obtained from small (1-2 mm), medium (3-5 mm) and large (6-11 mm) follicles were cultured under a serum-free condition in the presence or absence of follicle stimulating hormone (FSH; 20 ng/ml), with or without triiodothyronine (T3; 10-8M). Relative viability, proliferative activity, and apoptosis of cultured granulosa cells were evaluated with 3-(4.5-dimethylahiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT] assay, Ki67 expression and activated caspase-3 protein expression, respectively. MTT assay showed that T3 had no significant effect on the relative viability of granulosa cells regardless of the follicle size. Ki67-positive rate in small follicle granulosa cells was augmented by treatment with FSH whereas it was not affected by T3. Furthermore, FSH treatment decreased activated caspase-3 protein-positive rate of small follicle granulosa cells. Relative to the treatment with FSH alone, concomitant treatment with FSH and T3 resulted in further decrease in caspase-3 protein-positive rate in small follicle granulosa cells. Treatment with T3 alone did not affect the caspase-3 protein-positive rate. These results suggest that thyroid hormone synergizes with FSH to inhibit apoptosis in small follicle granulosa cells without affecting the proliferative potential of those cells.
 ...
PMID:Thyroid hormone synergizes with follicle stimulating hormone to inhibit apoptosis in porcine granulosa cells selectively from small follicles. 1514 Nov 46

Oxidative stress and depletion of the antioxidant glutathione (GSH) trigger apoptosis in many systems. Previous work showed that antioxidants prevented apoptosis as effectively as FSH in preovulatory follicles. We aimed to test the hypotheses that follicular reactive oxygen species (ROS) initiate apoptosis and that follicular GSH protects against apoptosis. Preovulatory follicles were isolated from ovaries of immature rats primed with pregnant mare serum gonadotropin. Negative control (0-h) follicles were processed immediately. Others were cultured for 2 to 48 h with 1) medium alone, 2) 75 ng/ml ovine FSH, or 3) FSH plus 100 mum buthionine sulfoximine (BSO), a specific inhibitor of GSH synthesis. Total GSH concentrations declined in follicles cultured without FSH for 48 h, whereas FSH increased GSH levels above those observed at 0 h. BSO suppressed GSH to undetectable levels. Treatment with FSH prevented apoptosis in granulosa cells, measured by terminal dUTP transferase-mediated nick-end-labeling and activated caspase 3 immunohistochemistry. Addition of BSO partially and significantly reversed the antiapoptotic effect of FSH on granulosa cells; supplementation of GSH completely prevented BSO-induced granulosa cell apoptosis. Whole-follicle ROS production, measured as dichlorofluorescein and rhodamine fluorescence using confocal microscopy, was significantly increased by 4 h of culture and increased further thereafter. FSH significantly suppressed ROS production, and the addition of BSO partially overcame this effect of FSH. These findings provide evidence that oxidative stress induces apoptosis in preovulatory follicles and that the antiapoptotic effect of FSH is mediated in part by stimulation of follicular GSH synthesis and suppression of ROS production.
 ...
PMID:Opposing effects of glutathione depletion and follicle-stimulating hormone on reactive oxygen species and apoptosis in cultured preovulatory rat follicles. 1633 98

Ovarian follicular atresia represents a selection process that ensures the release of only healthy and viable oocytes during ovulation. The transition from preantral to early antral stage is the penultimate stage of development in terms of gonadotropin dependence and follicle destiny (survival/growth vs. atresia). We have examined whether and how oocyte-derived growth differentiation factor 9 (GDF-9) and FSH regulate follicular development and atresia during the preantral to early antral transition, by a novel combination of in vitro gene manipulation (i.e. intraoocyte injection of GDF-9 antisense oligos) and preantral follicle culture. Injection of GDF-9 antisense suppressed basal and FSH-induced preantral follicle growth in vitro, whereas addition of GDF-9 enhanced basal and FSH-induced follicular development. GDF-9 antisense activated caspase-3 and induced apoptosis in cultured preantral follicles, a response attenuated by exogenous GDF-9. GDF-9 increased phospho-Akt content in granulosa cells of early antral follicles. Although granulosa cell apoptosis induced by ceramide was attenuated by the presence of GDF-9, this protective effect of GDF-9 was prevented by the phosphatidylinositol 3-kinase inhibitor LY294002 and a dominant negative form of Akt. Injection of GDF-9 antisense decreased FSH receptor mRNA levels in cultured follicles, a response preventable by the presence of exogenous GDF-9. The data suggest that GDF-9 is antiapoptotic in preantral follicles and protects granulosa cells from undergoing apoptosis via activation of the phosphatidylinositol 3-kinase/Akt pathway. An adequate level of GDF-9 is required for follicular FSH receptor mRNA expression. GDF-9 promotes follicular survival and growth during the preantral to early antral transition by suppressing granulosa cell apoptosis and follicular atresia.
 ...
PMID:Growth differentiation factor 9 is antiapoptotic during follicular development from preantral to early antral stage. 1674 Jun 54

cAMP response-element binding (CREB) transcription factors transduce cell survival responses to peptide hormones and growth factors in normal tissues and mutant CREB proteins are implicated in tumorigenesis. Ovarian cancer most frequently arises from the ovarian surface epithelium (OSE), possibly due to repeat inflammation-associated injury-repair episodes that promote neoplasia. We asked if post-receptor signalling involving the CREB family of proteins plays a role in OSE cell survival. In an ovine ovulation model, abundant expression of phospho-CREB/activating transcription factor (ATF) protein was detected immunohistochemically, strongly localised to OSE cells in the proximity of pre-ovulatory follicles. Treatment of primary sheep OSE cell cultures with LH stimulated cAMP accumulation and reduced apoptosis (caspase 3/7 activity) in response to serum withdrawal. When OSE cells were infected with an adenovirus containing a CRE-luciferase construct, exposure to LH and FSH induced CRE-directed transcription. Finally, when a non-phosphorylatable mutant of CREB (Ad CREB(S133A)) was adenovirally expressed, apoptosis measured by activation of caspases was increased several fold relative to that caused by transfection with wild-type CREB (Ad CREB(WT)) or lacZ (Ad lacZ). To test the potential clinical relevance of these findings, we expressed mutant CREB protein in normal human OSE cells from four women and a series of cell lines derived from human ovarian cancers. Infection with Ad CREB(S133A) markedly increased apoptosis in normal human OSE but had no detectable effect on apoptosis in any of the cancer cell lines. We conclude that CREB/ATF signalling is important for the maintenance of OSE cell survival in vitro and is altered in human cell lines derived from ovarian cancers.
 ...
PMID:cAMP response element-binding (CREB) signalling and ovarian surface epithelial cell survival. 1706 10

Atresia and luteolysis are well-documented processes in which most of the growing ovarian follicles and all corpora lutea, respectively, are eliminated by apoptosis. We have previously reported that LH and FSH enhance caspase-3 and -7 activity and apoptosis in the theca-interstitial cells of rat preovulatory follicles in culture. Here we have used cultured follicles to examine whether LH-induced caspase activation is related to the ability of LH to stimulate steroid production. In these studies, we used three inhibitors of enzymes involved in steroid production: aminoglutethimide and ketoconazole, acting on cytochrome P450 side-chain cleavage (P450scc) located at the mitochondria, and epostane, acting on 3beta-hydroxysteroid dehydrogenase located at the endoplasmic reticulum. We found that treatment with either aminoglutethimide or ketoconazole, but not with epostane, significantly reduced LH-induced caspase-3 and -7 activation and apoptosis, suggesting the mediation of LH-induced caspase activation by P450scc. Supplementing pregnenolone, the product of P450scc catalysis, to follicles treated with aminoglutethimide did not restore LH-induced caspase activation. On the other hand, treatment with antioxidants inhibited LH-induced caspase activation. Moreover, LH treatment was associated with an increase in reactive oxygen species which was inhibited by aminoglutethimide. Thus, P450scc catalysis results in an increase in reactive oxygen species, which in turn may trigger/facilitate caspase-3 activation. Finally, we found that in rat corpora lutea in vivo, an increase in steroidogenesis was accompanied by an increase in caspase activity. Thus, this study reveals a linkage between two seemingly distinct processes in which LH-induced caspase activation in cultured rat preovulatory follicles is coupled to mitochondrial steroidogenesis via P450scc.
 ...
PMID:Luteinizing hormone-induced caspase activation in rat preovulatory follicles is coupled to mitochondrial steroidogenesis. 1721 6


1 2 3 4 5 6 Next >>