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1.
Mol Hum Reprod ; 18(11): 535-45, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22763913

RESUMO

Corticotropin-releasing hormone (CRH) and its receptors are expressed in human placenta. Recently, the impaired function of this system has been associated with a number of complications of pregnancy, including pre-eclampsia. The aim of the study was to test the hypothesis that CRH participates in the pathophysiology of pre-eclampsia through the induction of macrophage-mediated apoptosis of extravillous trophoblasts (EVTs). We found that the expression of CRH was increased in the EVT of the placental bed biopsy specimens from pre-eclamptic pregnancies (1.8-fold increase; P < 0.05). In addition, significantly larger numbers of apoptotic EVT were detected in pre-eclamptic placentas compared with normal ones (P < 0.05), and only in pre-eclamptic placentas, decidual macrophages were found to be Fas ligand (FasL)-positive. In vitro studies on the effect of CRH on human macrophages suggested that CRH induced the expression of the FasL protein in human macrophages and potentiated their ability to induce the apoptosis of a Fas-expressing EVT-based hybridoma cell line in co-cultures. These findings demonstrate a possible mechanism by which the aberrant expression of CRH in pre-eclampsia may activate the FasL-positive decidual macrophages, impair the physiological turnover of EVT and eventually disturb placentation.


Assuntos
Hormônio Liberador da Corticotropina/genética , Decídua/metabolismo , Macrófagos/metabolismo , Pré-Eclâmpsia/genética , Trofoblastos/metabolismo , Apoptose , Western Blotting , Linhagem Celular Tumoral , Técnicas de Cocultura , Hormônio Liberador da Corticotropina/biossíntese , Hormônio Liberador da Corticotropina/farmacologia , Decídua/patologia , Proteína Ligante Fas/genética , Proteína Ligante Fas/metabolismo , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Macrófagos/patologia , Placentação , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Trofoblastos/patologia
2.
Hum Reprod ; 27(12): 3365-79, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23097354

RESUMO

BACKGROUND: The American Society for Reproductive Medicine (ASRM) and the European Society of Human Reproduction and Embryology (ESHRE) are the two largest societies in the world whose members comprise the major experts and professionals working in the field of reproductive medicine and embryology. These societies have never before had a joint scientific meeting. METHODS: A 3-day meeting was planned and took place in March of 2012. The goal was to present and debate key topics, as well as modes of practice in reproductive medicine and to discuss recent developments in the field. RESULTS: Presentations by members of ASRM and ESHRE were of three types: 'state of the art' lectures, 'back-to-back' presentations of two points of view and debates. CONCLUSIONS: For the first time, ASRM and ESHRE held a joint meeting where a special emphasis was given to presentations on the hottest topics in the field. Although different opinions and approaches sometimes exist on the two sides of the Atlantic, an appreciation and acceptance of these differences was evident, and there was more commonality than divergence of opinion.


Assuntos
Embriologia , Medicina Reprodutiva , Sociedades Médicas , Adulto , Endometriose/tratamento farmacológico , Europa (Continente) , Feminino , Substâncias Perigosas/efeitos adversos , Humanos , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/fisiopatologia , Síndrome do Ovário Policístico/terapia , Gravidez , Técnicas de Reprodução Assistida , Estados Unidos
3.
Gynecol Endocrinol ; 28(4): 330-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22114766

RESUMO

UNLABELLED: AIM AND SETTING: To test the effects of crude extracts from flax (Linum usitatissimum) on progesterone and estradiol and ERα and ß/PR production in choriocarcinoma cell lines Jeg 3 and BeWo. Tumor trophoblast cells (Jeg 3 and BeWo) were incubated in the presence of different concentrations of the flax crude extracts. Estradiol and progesterone production was measured. Estrogen receptor α and ß as well as progesterone receptor expressions were also assessed. RESULTS: In Jeg 3 cells, progesterone production was downregulated by flax root and leaves extract, while in BeWo cells only flax root extract did manage to downregulate progesterone production. ERß expression was significantly downregulated by flax root and flax leaves extract in both cell lines; on the contrary, ERα expression was increased by flax leaves extract in BeWo cells. PR expression was downregulated by flax leaves extract in Jeg 3 and by flax root extract in BeWo cells. CONCLUSION: Flax extracts derived from leaves and especially from roots can modify progesterone and possibly estradiol production, while at the same time they seem to alter ERß expression. Further studies on animal models and adequately designed retrospective epidemiological studies are imperative to clarify this role upon progesterone.


Assuntos
Estradiol/metabolismo , Linho , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Progesterona/metabolismo , Trofoblastos/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Coriocarcinoma/tratamento farmacológico , Coriocarcinoma/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Gravidez , Receptores de Progesterona/metabolismo , Trofoblastos/metabolismo , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/metabolismo
4.
Histochem Cell Biol ; 132(2): 159-67, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19387680

RESUMO

Pinopodes represent the morphological and integrins, the biomolecular markers of endometrial receptivity. We studied using scanning electron microscopy, the expression of pinopodes on tubal samples and their corresponding endometria, from 21 women of reproductive age (7 from proliferative phase, 7 from day LH +5 and 7 from day LH +7). In addition, we examined the immunohistochemical staining of integrins alpha v beta 3, alpha v beta 5 and their ligands, fibronectin (FN) and osteopontin (OPN) in the same tubal epithelium samples. Pinopodes were detected on the tubal epithelium exclusively during day LH +7, coincident with their formation in the endometrium and synchronous to alpha v beta 3 sharp increase in the oviduct epithelium, suggesting a regulation similar to the endometrium. In contrast, alpha v beta 5, FN and OPN remained unchanged during the cycle. These results show for the first time the formation of pinopodes in the tubal epithelium at the time of endometrial receptivity and correlate it with the upregulation of the intact dimmer alpha v beta 3 in the tubes.


Assuntos
Implantação do Embrião , Endométrio/fisiologia , Tubas Uterinas/fisiologia , Integrina alfaVbeta3/biossíntese , Adulto , Biomarcadores/análise , Biomarcadores/metabolismo , Endométrio/citologia , Endométrio/metabolismo , Epitélio/metabolismo , Epitélio/fisiologia , Tubas Uterinas/citologia , Tubas Uterinas/metabolismo , Feminino , Fibronectinas/análise , Fibronectinas/biossíntese , Humanos , Imuno-Histoquímica , Integrina alfaVbeta3/análise , Pessoa de Meia-Idade , Osteopontina/análise , Osteopontina/biossíntese , Receptores de Vitronectina/análise , Receptores de Vitronectina/biossíntese
5.
Fetal Diagn Ther ; 23(3): 198-203, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18417978

RESUMO

OBJECTIVES: To investigate if skewed X-chromosome inactivation (XCI) is associated with unexplained recurrent miscarriage (RM) in Greek women. METHODS: This was a prospective case-control study. A methylation-sensitive assay was used to investigate the X-inactivation pattern of women with unexplained RM and controls. RESULTS: Fifty-six of the 74 patients (75.7%) and 55 of 80 controls (68.8%) were informative. Among the informative cases, 6/56 (10.7%) women showed extreme XCI (>90%) and among the informative controls, 2/55 (3.6%) showed extreme XCI. CONCLUSIONS: In the present study, women with unexplained RM showed a statistically nonsignificant increase in skewed XCI prevalence (10.7%) compared with control women (3.6%; p = 0.271).


Assuntos
Aborto Habitual/genética , Inativação do Cromossomo X , Adulto , Estudos de Casos e Controles , Feminino , Grécia , Heterozigoto , Humanos , Masculino , Razão de Chances , Reação em Cadeia da Polimerase , Gravidez , Estudos Prospectivos , Receptores Androgênicos/genética
6.
Toxicology ; 409: 137-143, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30055296

RESUMO

Acetylcholinesterase inhibitors are widely used for a variety of medical, agricultural and public health purposes. Consequently, exposure is highly possible during lifetime. However, their systematic use raises concerns for the potential impact on the fetus and newborn since these substances may affect angiogenesis, the neonatal and maternal intensive care, neuroimmune function and response, mammary growth/lactation via cholinergic/non-cholinergic central and peripheral neuroendocrine pathways. New methodologies, neuroscientific technologies and research studies are needed to harness existing knowledge along with the proper management, availability for new acetylcholinesterase inhibitors, with stable pharmacodynamics and clinical outcomes.


Assuntos
Inibidores da Colinesterase , Embrião de Mamíferos/efeitos dos fármacos , Animais , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Embrião de Mamíferos/fisiologia , Humanos , Teratogênicos/farmacologia
7.
Placenta ; 28(2-3): 127-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16698078

RESUMO

Urocortin (UCN) is a 40 amino acid peptide which is closely related to corticotropin-releasing hormone and binds with high affinity to both CRH type 1 and type 2 receptors. UCN is expressed in human reproductive tissues including endometrium, ovary, and placenta. This study was designed to investigate the cellular localization of UCN at the implantation site of the human blastocyst, as well as the regulation of the UCN promoter by two major intracellular signaling pathways, the cAMP/PKA and diacylglycerol/PKC pathways, in cells of placental origin. For this reason, immunohistochemistry was performed on tissue sections from paraffin-embedded human first trimester placentas and freshly isolated human invasive extravillous trophoblast cells (EVT) were analyzed for UCN expression using RT-PCR and immunofluorescence. Finally, UCN promoter activity was analyzed in the JEG3 human choriocarcinoma cell line. Immunohistochemistry revealed expression of UCN in the cytotrophoblast, the EVT and decidual cells. Both UCN mRNA and peptide were detectable in freshly isolated EVT. Finally, a human UCN promoter luciferase reporter construct transfected into JEG3 cells was significantly inducible by phorbol ester plus ionomycin, but not by phorbol ester alone or by forskolin. Collectively, the present study reports the expression of UCN in EVT and the activation of the UCN gene promoter by the diacylglycerol/PKC pathway. The functional significance of urocortin for the physiology of EVT requires further investigation.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Implantação do Embrião/fisiologia , Gravidez/metabolismo , Trofoblastos/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Ionomicina , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Acetato de Tetradecanoilforbol , Urocortinas
8.
Int J Gynaecol Obstet ; 97(2): 115-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17368647

RESUMO

OBJECTIVE: To investigate whether corticotropin-releasing hormone (CRH) and corticotropin (ACTH) plasma concentrations in women diagnosed with preterm labor are of potential clinical value in the assessment of the risk of preterm birth. METHOD: Plasma samples of 79 women diagnosed with preterm labor were used in this study. Samples were divided into three groups based on the week of gestation (24th-28th, 29th-32nd, 33rd-37th). CRH and ACTH values were determined by ELISA. RESULT: Mean maternal peripheral plasma values of CRH and ACTH were significantly higher (p<0.001) in women who were initially diagnosed with preterm labor and finally delivered a preterm birth, compared to women with the same diagnosis but with term birth. CONCLUSION: CRH and ACTH serum levels in women diagnosed with preterm labor could be used as predictors for the timing of parturition.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina/sangue , Trabalho de Parto Prematuro/sangue , Nascimento Prematuro/diagnóstico , Adulto , Biomarcadores , Feminino , Idade Gestacional , Humanos , Trabalho de Parto Prematuro/fisiopatologia , Valor Preditivo dos Testes , Gravidez
9.
Curr Med Chem ; 13(23): 2751-60, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17073626

RESUMO

CRF, CRF-related peptides and CRF receptors constitute a complex physiological system which has a key role in facilitating the adaptation of the organism to the stressful stimuli of the environment. The behavioral, endocrine, autonomic and immune branches of stress response are considered to be under the coordinating effects of CRF and its related peptides. The effects of these peptides are mediated through two distinct receptors, types 1 and 2 CRF receptors (CRF(1) and CRF(2)). The two receptors are encoded by separate genes and belong to the G-coupled receptor superfamily. The wide influence of the CRF system on physiological processes in both brain and periphery, suggests the implication of the respective peptides in the pathophysiology of numerous disorders which involve dysregulated stress responses. The potential use of CRF antagonists in such disorders is currently under intense investigation. Furthermore, such compounds have been invaluable in elucidating the physiology of the CRF system. This review will focus on existing data on the structural and pharmacological characteristics as well as the experimental and potential clinical uses of non-peptide, small molecule CRF antagonists.


Assuntos
Hidrocarbonetos Aromáticos/farmacologia , Hidrocarbonetos Aromáticos/uso terapêutico , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Animais , Desenho de Fármacos , Humanos , Hidrocarbonetos Aromáticos/química , Ligantes , Estrutura Molecular , Oligopeptídeos/química , Relação Estrutura-Atividade
10.
Endocr Pathol ; 17(1): 19-33, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16760577

RESUMO

During human pregnancy the placenta produces a variety of proteins for the establishment of the fetoplacental unit, including inhibins and activins. Inhibins are dimeric glycoproteins, composed of an alpha-subunit and one of two possible beta-subunits (betaA or betaB). Aims of the present study were (a) the determination of the frequency and tissue distribution patterns of the inhibin/activin subunits in human placental tissue of normal pregnancies and pregnancies complicated with preeclampsia and HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) and (b) the assessment of a combined expression of inhibin-alpha- and both beta-subunits (betaA-and betaB-subunits) using double immunofluorescence technique. A significant lower expression of the inhibin-alpha subunit in preeclamptic and HELLP placental tissue compared to normal pregnancies was observed, while the inhibin-alpha immunostaining was significantly upregulated in syncytotrophoblast. Additionally, we demonstrated a significant down-regulation of inhibin-betaB subunit in extravillous trophoblast cells between normal and preeclamptic compared to HELLP placental tissue, while inhibin-betaA-subunit was significantly higher in preeclamptic syncytotrophoblast cells. A colocalization of inhibin-alpha and the beta-subunits could be demonstrated, suggesting a production and secretion of intact inhibin A and inhibin B. Therefore, inhibin A and activin A might be useful markers in preeclampsia. Valuable parameters in HELLP syndrome could be inhibin A, rather than inhibin B, and activin B. Furthermore, the lower betaB-subunit production in extravillous trophoblast cells demonstrates that this subunit might have an important role in the pathogenesis of HELLP syndrome. Additionally, the higher production of the betaA-subunit in syncytotrophoblast cells suggest a higher production of activin A rather than inhibin A in preeclampsia that might be utilized as a marker of placental function.


Assuntos
Síndrome HELLP/metabolismo , Subunidades beta de Inibinas/metabolismo , Inibinas/metabolismo , Pré-Eclâmpsia/metabolismo , Trofoblastos/metabolismo , Adulto , Biomarcadores/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Síndrome HELLP/patologia , Humanos , Técnicas Imunoenzimáticas , Pré-Eclâmpsia/patologia , Gravidez , Trofoblastos/patologia
11.
Clin Cancer Res ; 5(6): 1523-37, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10389942

RESUMO

Epithelial ovarian cancer (EOC) remains localized within the peritoneal cavity in a large number of patients, lending itself to i.p. approaches of therapy. In the present study, we investigated the effect of replication-selective herpes simplex virus-1 (HSV-1) used as an oncolytic agent against EOC and the use of human teratocarcinoma PA-1 as carrier cells for i.p. therapy. HSV-1716, a replication-competent attenuated strain lacking ICP34.5, caused a direct dose-dependent oncolytic effect on EOC cells in vitro. A single i.p. administration of 5 x 10(6) plaque-forming units resulted in a significant reduction of tumor volume and tumor spread and an increase in survival in a mouse xenograft model. PA-1 cells supported HSV replication in vitro and bound preferentially to human ovarian carcinoma surfaces compared with mesothelial surfaces in vitro and in vivo. In comparison with the administration of HSV-1716 alone, irradiated PA-1 cells, infected at two multiplicities of infection with HSV-1716 and injected i.p. at 5 x 10(6) cells/animal, led to a significant tumor reduction in the two models tested and the significant prolongation of mean survival in one model. Histological evaluation revealed extensive necrosis in tumor areas infected by HSV-1716. Immunohistochemistry against HSV-1 revealed areas of viral infection within tumor nodules, which persisted for several weeks after treatment. Administration of HSV-infected PA-1 carrier cells resulted in larger areas of tumor infected by the virus. Our results indicate that replication-competent attenuated HSV-1 exerts a potent oncolytic effect on EOC, which may be further enhanced by the utilization of a delivery system with carrier cells, based on amplification of the viral load and possibly on preferential binding of carrier cells to tumor surfaces.


Assuntos
Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/terapia , Simplexvirus/genética , Teratocarcinoma/virologia , Animais , Adesão Celular , Sobrevivência Celular/efeitos da radiação , Efeito Citopatogênico Viral , Feminino , Herpes Simples/patologia , Herpes Simples/virologia , Humanos , Imuno-Histoquímica , Injeções Intraperitoneais , Camundongos , Camundongos SCID , Transplante de Neoplasias , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/virologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/virologia , Taxa de Sobrevida , Teratocarcinoma/patologia , Células Tumorais Cultivadas , Replicação Viral
12.
Clin Cancer Res ; 6(8): 3342-53, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10955822

RESUMO

Replication-restricted herpes simplex virus-1 (HSV-1) strains lacking ICP34.5 are emerging as powerful anticancer agents against several solid tumors including epithelial ovarian cancer (EOC). Although chemotherapy-resistant tumors would be likely candidates for treatment with HSV-1 mutants lacking ICP34.5, the efficacy of these mutants on such tumors is unknown. In the present study, we investigated whether chemotherapy resistance affects the response of ovarian cancer cells to HSV-R3616, an ICP34.5-deficient, replication-restricted HSV-1. Primary EOC cultures obtained from patients who varied in their responses to platinum/paclitaxel induction chemotherapy displayed similar sensitivity to HSV-R3616. Similarly, chemotherapy-sensitive ovarian cancer cells A2780 and PA-1, possessing wild-type p53, and their respective chemotherapy-resistant clones A2780/200CP, lacking p53 function, and PA-1/E6, permanently expressing the HPV E6 gene, were equally sensitive to HSV oncolysis. Because wild-type HSV can kill cells by apoptosis and nonapoptotic mechanisms, we investigated the involvement of apoptosis and the role of the p53 tumor suppressor gene in oncolysis induced by HSV-R3616. Infection of ovarian cancer cell lines by HSV-R3616 was followed by cell death via apoptosis or nonapoptotic mechanisms as noted by morphology, cell cycle analysis, and in situ TUNEL assay. p53 protein levels remained unchanged, and Bax protein levels decreased in cells possessing intact p53 and that mainly underwent HSV-induced apoptosis. Loss of p53 function did not affect the frequency or rate of apoptosis or the sensitivity of EOC cells to the oncolytic effect of HSV-R3616. These results suggest that recombinant HSV-1 lacking ICP34.5 is capable of killing ovarian cancer cells that lack p53 function, resist apoptosis, and/or are chemotherapy resistant. These data support the hypothesis that HSV-based oncolytic therapy may be efficacious in chemotherapy-resistant tumors, including tumors that are deficient in p53.


Assuntos
Herpesvirus Humano 1/fisiologia , Neoplasias Ovarianas/terapia , Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Supressora de Tumor p53/fisiologia , Proteínas Virais/fisiologia , Antineoplásicos/farmacologia , Apoptose/fisiologia , Morte Celular/fisiologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/metabolismo , Humanos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/virologia , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo , Proteínas Virais/genética , Replicação Viral , Proteína X Associada a bcl-2
13.
Eur J Obstet Gynecol Reprod Biol ; 121(1): 77-80, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15989987

RESUMO

OBJECTIVE: To examine whether exogenous LH administration has a beneficial effect on the quality of oocytes, fertilization potential, as well as pregnancy rate in IVF-ET cycles. A randomized trial comparing r-FSH versus r-FSH and LH was employed. STUDY DESIGN: Forty-six infertile couples entering IVF-ET for the first time (either tubal or male factor) were divided after prospective randomization into two groups. In both groups the long protocol with GnRH-analogs was used. In group A, ovarian stimulation started with r-FSH (200 IU/day) for the first four days. In group B, the stimulation protocol started with one amp hMG (75 IU FSH + 75 IU LH activity) daily for four days, with simultaneous administration of r-FSH (150 IU/day). The outcome was compared. RESULTS: Statistical difference was observed in the number of mature oocytes, the number of fertilized oocytes as well as the number of transferable embryos. In all cases, results were statistically significantly better (p < 0.05) in group B. Clinical pregnancy rate, finally, was similar in the two groups. CONCLUSION: The relatively small sample size does not allow a definitive conclusion for the important role of LH during early oocyte maturation. Our results, however, indicate a beneficial effect when small doses of LH are used for ovarian stimulation in IVF-ET cycles. This effect may be more important in cases in which few embryos are available for transfer.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Indução da Ovulação/métodos , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Infertilidade Feminina/terapia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Valores de Referência , Medição de Risco , Resultado do Tratamento
14.
Endocrinology ; 131(2): 703-9, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1353443

RESUMO

The PC12 is a cloned rat pheochromocytoma cell line that retains a number of chromaffin cell characteristics, such as the presence of nicotinic cholinergic receptors, the synthesis and secretion of catecholamines, and the expression of a number of neuropeptide genes. The PC12 cell line is a useful model for the study of neuronal development, since PC12 cells can be induced to differentiate toward sympathetic neurons after exposure to nerve growth factor (NGF). PC12 cells can also be induced to differentiate toward the opposite direction, i.e. toward mature chromaffin cells. Morphological and biochemical changes mark the differentiation of PC12 cells toward either direction. Among the substances proposed as biochemical markers of PC12 cell differentiation toward chromaffin cells is the endogenous opioid precursor proenkephalin and its posttranslational peptide products. Indeed, the proenkephalin gene is expressed in both adrenal chromaffin and PC12 cells. The secretion of enkephalins from PC12 cells increases by several-fold after differentiation toward chromaffin cells. On the other hand, prodynorphin (another endogenous opioid precursor) is not present in normal adrenal chromaffin cells, but it is synthesized by human pheochromocytomas. It, thus, appears that dedifferentiation of chromaffin cells induces expression of the prodynorphin gene. Consequently, the aim of this study was to determine whether the rat pheochromocytoma-derived PC12 cell line expresses the prodynorphin gene, if it secretes dynorphins, and if the NGF-induced differentiation of PC12 cells toward sympathetic neurons affects the secretion of the latter. We found the following. 1) PC12 cells synthesize prodynorphin and secrete its peptide products. 2) The size of the prodynorphin transcript and the mol wt of its dominant form of dynorphin appear to be similar or identical to those of prodynorphin in rat anterior pituitary. 3) PC12 dynorphin secretion is increased, in a dose-dependent manner, after nicotinic cholinergic stimulation, an effect blocked by the specific nicotine antagonist hexamethonium. Thus, it appears that after cholinergic stimulation, PC12 dynorphin is cosecreted with catecholamines, a phenomenon described for a number of neuropeptides, including the proenkephalin-derived opioids. 4) The NGF-mediated differentiation of PC12 cells into sympathetic neurons exerted a stimulatory effect on basal, nicotine-induced, and depolarization-dependent dynorphin secretion. However, NGF did not shift the nicotine dose-response curve of dynorphin secretion. In conclusion, it appears that while changes in the secretion of proenkephalin-derived peptides may serve as a marker of PC12 cell differentiation toward chromaffin cells, an increase in the secretion of prodynorphin-derived peptides may represent a marker of NGF-induced differentiation of PC12 cells toward sympathetic neurons.


Assuntos
Dinorfinas/metabolismo , Encefalinas/biossíntese , Fatores de Crescimento Neural/farmacologia , Nicotina/farmacologia , Precursores de Proteínas/biossíntese , Animais , Northern Blotting , Diferenciação Celular , Cromatografia em Gel , Dinorfinas/biossíntese , Dinorfinas/genética , Encefalinas/química , Encefalinas/genética , Expressão Gênica , Hexametônio , Compostos de Hexametônio/farmacologia , Peso Molecular , Células PC12 , Cloreto de Potássio/farmacologia , Precursores de Proteínas/química , Precursores de Proteínas/genética , RNA Mensageiro/análise , Ratos
15.
J Clin Endocrinol Metab ; 85(1): 449-59, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634423

RESUMO

It has been previously demonstrated that the gonadotropin-mediated inhibition ofapoptosis in rat ovarian granulosa cells is associated with changes in the expression of several cell death-regulatory genes, including p53. In addition, it has been shown that the actions of p53 may be amplified through a cooperative interaction with the Wilms' tumor suppressor gene product (WT1). Based on these findings, the present studies were conducted to determine whether p53 and WT1 are expressed and gonadotropin regulated in the human ovary and to study the relationship between tumor suppressor gene expression and apoptosis in human granulosa/lutein cells (GCs). Analysis of total RNA prepared from human GCs using the RT-PCR demonstrated the presence of p53 messenger RNA (mRNA) and four WT1 mRNA splice variants. These observations were supported by Northern blot analysis of total RNA prepared from human GCs, which revealed the presence of a single (approximately 2.8 kb) p53 mRNA transcript and two primary (approximately 1.8 and approximately 3.5 kb) WT1 mRNA transcripts. Western blot analysis of nuclear protein extracts from human GCs yielded one immunoreactive protein of the expected size (approximately 53 kDa) recognized by a p53 antibody and one immunoreactive protein of the expected size (approximately 52-54 kDa) recognized by the WT1 antibody. Immunohistochemical staining showed that both molecules were localized to nuclei of human GCs and were coordinately regulated during follicular development. Immunofluorescence analysis showed that p53 protein was localized exclusively to nuclei of GCs undergoing apoptosis during in vitro culture and was similarly localized to nuclei and cytoplasm of apoptotic granulosa cells in atretic follicles in vivo. To further evaluate whether human GC apoptosis is linked to increased expression of tumor suppressor genes, we analyzed levels of p53 and WT1 mRNA and protein in GCs induced to undergo apoptosis in vitro. Healthy (nonapoptotic) GCs snap-frozen immediately after isolation from patients undergoing in vitro fertilization-embryo transfer possessed relatively low, but detectable, levels of p53 and WT1 mRNA and protein. However, following serum-free culture to induce apoptosis, p53 mRNA and protein levels increased significantly after 24 h, paralleling the increase in the number of apoptotic GCs. The induction of both p53 mRNA and protein in GCs was inhibited by the addition of human CG to the culture medium. In contrast, WT1 mRNA and protein levels remained constitutive in GCs incubated for 24 h compared with GCs snap-frozen immediately after isolation. We conclude that the p53 and WT1 genes are expressed at the mRNA and protein levels in human GCs and that expression of p53 is regulated during follicular maturation. Nuclear accumulation of p53 protein occurs in human GCs during apoptosis in vitro and in vivo, and p53 mRNA and protein are up-regulated in GCs starved of hormonal support but down-regulated by the presence of human CG. We propose that the products of these two principal tumor suppressor genes serve as important regulators of human follicular development and corpus luteum function.


Assuntos
Regulação da Expressão Gênica/fisiologia , Genes Supressores de Tumor/genética , Genes do Tumor de Wilms/genética , Genes p53/genética , Folículo Ovariano/fisiologia , Ovário/metabolismo , Adulto , Apoptose/fisiologia , Northern Blotting , Células Cultivadas , Manutenção do Corpo Lúteo/fisiologia , DNA Complementar/genética , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica/genética , Humanos , Immunoblotting , Indicadores e Reagentes , Gravidez , RNA/genética , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
J Clin Endocrinol Metab ; 75(2): 584-9, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1639959

RESUMO

Immunoreactive beta-endorphin (IR-beta END) is present in human endometrium. Several indirect lines of evidence suggest that endometrial beta END is under steroid hormone control, i.e. IR-beta END is detectable in the secretory, but not the proliferative, endometrium, and progesterone administration increases the concentration of IR-beta END in uterine secretions of ovariectomized gilts. To study the effect of steroid hormones on endometrial beta END, we first questioned whether Ishikawa human endometrial adenocarcinoma cells (which respond to steroid hormones) express the proopiomelanocortin (POMC) gene. Indeed, on Northern blot analysis, a RNA similar or identical in size to pituitary POMC mRNA was present in Ishikawa cell RNA extracts. IR-beta END was also present in Ishikawa cell extracts and culture medium, which coeluted with synthetic human beta END in a Sephadex G-50 column. Ishikawa cells released most of their IR-beta END into the culture medium. Estradiol decreased the release of IR-beta END from Ishikawa cells, an effect that was dependent upon dose and time. The maximal effect was observed after a 4-day exposure to 10 nM estradiol (44 +/- 6% of the control value; n = 6; P less than 0.001). This effect was almost completely counteracted by a 100-fold excess of the antiestrogen 4-hydroxytamoxifen. Progesterone and dihydrotestosterone did not have a statistically significant effect on IR-beta END release. Dexamethasone had effects similar to those of estradiol, i.e. decreased the release of IR-beta END in a time- and dose-dependent manner. The maximal effect was detected after a 4-day exposure to 10 nM dexamethasone (53 +/- 6% of the control value; n = 6; P less than 0.001). Interestingly, the antiprogestin-antiglucocorticoid RU486 exhibited agonistic properties, i.e. diminished the release of IR-beta END in a time- and dose-dependent fashion, possibly via the glucocorticoid receptor. Its maximal effect was reached after a 4-day exposure to 10 nM RU486 (55 +/- 6% of the control value; n = 6; P less than 0.001). In conclusion, our data demonstrate that the release of IR-beta END from Ishikawa cells in culture is inhibited by estradiol and dexamethasone, suggesting that endometrial beta END is under estrogen and glucocorticoid regulation, as is the case with hypothalamic and pituitary POMC-derived peptides. This is the first time that the in vitro release of a peripheral-extracranial POMC-derived peptide has been found to be under the direct control of estrogens and glucocorticoids.


Assuntos
Endométrio/metabolismo , Hormônios/farmacologia , Esteroides/farmacologia , beta-Endorfina/metabolismo , Dexametasona/farmacologia , Endométrio/patologia , Estradiol/farmacologia , Feminino , Humanos , Ensaio Imunorradiométrico , Mifepristona/farmacologia , Pró-Opiomelanocortina/genética , Progesterona/farmacologia , RNA Mensageiro/metabolismo , Esteroides/antagonistas & inibidores , Células Tumorais Cultivadas
17.
J Clin Endocrinol Metab ; 80(1): 185-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7829610

RESUMO

CRH is produced by several intrauterine sites, including placenta and desidua, during pregnancy. However, no data are available regarding the presence of CRH in the nonpregnant uterus. We now report that CRH is produced in the epithelial cells of normally cycling human uterus and in an endometrial epithelial cell-derived tumor. Specifically, we have found that: 1) Northern blot hybridization analysis of normal glandular endometrium as well as of Ishikawa human endometrial adenocarcinoma cells showed the presence of the CRH messenger RNA; the size of the transcript seemed to be identical to that present in human placenta and rat hypothalamus; 2) immunoreactive CRH (ir-CRH) was detectable in normal dispersed glandular endometrial cells as well as in the Ishikawa adenocarcinoma cells; 3) gel filtration chromatography of normal glandular endometrial and Ishikawa cell extracts and their culture media showed that most ir-CRH present had the mol wt of the authentic CRH peptide; in addition, a larger form of ir-CRH was also present in both normal and tumoral endometrial epithelial cell extracts; the latter most probably correspondents to CRH precursor molecules; and 4) immunofluorescence staining of CRH in normal glandular endometrial and Ishikawa cells revealed a cytoplasm rich in granules positive for ir-CRH. Our findings suggest that CRH may play an important role in the physiological events taking place within the uterine cavity, since CRH seems to be present in nonpregnant as well as pregnant uteri. Since CRH is expressed in normal endometrial epithelial cells and in an epithelial tumoral cell line, we propose the use of the Ishikawa cell line as a convenient model for the in vitro study of endometrial CRH.


Assuntos
Adenocarcinoma/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Adenocarcinoma/patologia , Northern Blotting , Cromatografia em Gel , Neoplasias do Endométrio/patologia , Endométrio/citologia , Células Epiteliais , Epitélio/metabolismo , Feminino , Imunofluorescência , Humanos , Valores de Referência , Células Tumorais Cultivadas
18.
J Clin Endocrinol Metab ; 86(12): 5964-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11739471

RESUMO

The Wilms' tumor suppressor gene (WT1) encodes a zinc-finger containing transcription factor that is selectively expressed in the developing urogenital tract and functions as a tissue-specific developmental regulator. In addition to its gene-regulatory function through DNA binding properties, WT-1 also regulates transcription by formation of protein-protein complexes. These properties place WT-1 as a major regulator of cell growth and differentiation. In view of these observations, we studied WT1 mRNA and protein in human endometrial extracts and in endometrial stromal cells (ESCs) differentiating into decidual cells in vitro, by RT-PCR and Western blotting, respectively. WT1 protein expression was also studied in situ in the proliferative and the secretory phase of the menstrual cycle in the early pregnant state. Analysis by PCR of total RNA prepared from human ESCs demonstrated the presence of WT1 mRNA and four WT1 mRNA splice variants. Western blot analysis of nuclear protein extracts from ESCs yielded one immunoreactive protein of the expected size (approximately 52-54 kDa) recognized by the WT1 antibody. Immunohistochemical staining showed that WT1 protein is localized only to nuclei of human endometrial stromal cells. It remains constant in the proliferative and the secretory phase of the menstrual cycle and is increased remarkably during decidualization in early pregnancy. ESCs decidualized in vitro were investigated for WT-1 expression, which confirmed that decidualizing stimuli (E2, medroxy-progesterone-acetate, and relaxin for 12 d or cAMP and progesterone for 1-4 d) induced WT-1 mRNA (P < 0.05) and increased protein levels (P < 0.05). These data indicate that in humans the WT1 gene is expressed in ESCs and its mRNA and protein levels remain constant in the proliferative and the secretory phase of the menstrual cycle and that WT1 mRNA and protein expression increases significantly in ESCs when these cells differentiate into decidual cells.


Assuntos
Endométrio/fisiologia , Expressão Gênica , Genes do Tumor de Wilms , Células Cultivadas , Decídua/fisiologia , Endométrio/citologia , Feminino , Regulação da Expressão Gênica , Humanos , Ciclo Menstrual/fisiologia , Gravidez , RNA Mensageiro/metabolismo , Células Estromais/metabolismo , Proteínas WT1/metabolismo
19.
J Clin Endocrinol Metab ; 84(11): 4239-45, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566679

RESUMO

The present investigation examined the effect of interleukin-1beta (IL-1beta) on progesterone production by human luteal cells and the expression and localization of the IL-1 system in the human corpus luteum (CL). Luteal cells were isolated from corpora lutea collected throughout the luteal phase. After dispersion, luteal cells were treated with a panel of monoclonal antibodies directed to leukocyte-specific molecules. The leukocytes were isolated with immunomagnetic beads. Leukocyte-free luteal cells exhibited greater steroidogenic responsiveness to hCG toward the end of the luteal phase. The treatment of mixed luteal cells (total luteal cells) with IL-1beta inhibited by 60% hCG-stimulated progesterone production. Interestingly, the treatment of leukocyte-free luteal cells with IL-1beta did not affect progesterone production. In addition, the treatment of mixed luteal cells with monoclonal antibodies against IL-1 receptor type I (IL-1RtI) resulted in a 2.5-fold increase in the hCG-supported progesterone production. IL-1RtI and IL-1 receptor antagonist were localized by immunohistochemistry in both somatic and immune cells of the CL. Flow cytometric analysis indicated that both nonleukocyte luteal cells and leukocyte-luteal cells exhibited IL-1Rt-I positive cells, representing 56% and 31% of the total luteal cells, respectively. However, 13% of nonleukocyte luteal cells did not express IL-1Rt-I. Northern analysis demonstrated the presence of the 5.1-kb IL-1RtI messenger ribonucleic acid transcript in CL of different ages. RT-PCR indicated that both leukocyte-free luteal cells and luteal leukocytes express IL-1RtI messenger ribonucleic acid. We conclude that 1) luteal leukocytes have an inhibitory effect on hCG-stimulated progesterone production; 2) IL-1beta inhibits hCG-stimulated progesterone production only in mixed luteal cell cultures, indicating that leukocytes mediate the effect; 3) the somatic and immune cells of the CL are sites of action and expression of the IL-1 system; and 4) interaction between the steroidogenic and immune cells of the CL suggests a functional intraovarian role for IL-1beta in CL physiology.


Assuntos
Corpo Lúteo/metabolismo , Interleucina-1/farmacologia , Células Lúteas/metabolismo , Progesterona/biossíntese , Adulto , Anticorpos Monoclonais/farmacologia , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/química , Corpo Lúteo/citologia , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Cinética , Leucócitos/química , Leucócitos/fisiologia , Fase Luteal , RNA Mensageiro/análise , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Cancer Gene Ther ; 7(2): 275-83, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10770637

RESUMO

Recombinant strains of herpes simplex virus-1 (HSV-1) harboring mutations in the infected cell product (ICP)34.5 region lose their neurovirulence and replicate more efficiently in dividing tumor cells than stationary cells, becoming replication-selective oncolytic agents. Additional mutation of the ICP6 gene, which encodes ribonucleotide reductase, further impairs the ability of HSV-1 mutants to replicate in normal cells, enhancing tumor selectivity. The present study investigated the effect of HSV-G207, a recombinant HSV-1 lacking ICP34.5 and ICP6, against epithelial ovarian cancer (EOC) in vitro and in vivo in a mouse xenograft model. To assess the selectivity of multimutated HSV-G207 against malignant cells, HSV-G207 and wild-type HSV-F were comparatively tested against normal human peritoneal mesothelial cells and EOC cells in vitro. HSV-G207 infected both EOC cells and mesothelial cells; however, unlike EOC cells, mesothelial cells provided a poor substrate for replication of HSV-G207. In contrast to wild-type HSV-F, HSV-G207 exerted a potent oncolytic effect on EOC cells but spared normal mesothelial cells in vitro. Primary EOC cells were more sensitive to the virus than established EOC cell lines. A single intraperitoneal injection of HSV-G207 resulted in a significant reduction in tumor volume and tumor spread in vivo. HSV-G207 was shown to penetrate deeply within tumor nodules and caused no apparent intraperitoneal toxicity. Oncolytic therapy with multimutated replication-restricted HSV may offer a novel approach in the treatment of EOC.


Assuntos
Carcinoma/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/patogenicidade , Mutação/genética , Neoplasias Ovarianas/virologia , Animais , Carcinoma/patologia , Carcinoma/terapia , Transformação Celular Viral/genética , DNA Recombinante/genética , DNA Recombinante/metabolismo , DNA Recombinante/uso terapêutico , DNA Viral/genética , DNA Viral/metabolismo , DNA Viral/uso terapêutico , Epitélio/virologia , Feminino , Herpesvirus Humano 1/fisiologia , Humanos , Infusões Parenterais , Camundongos , Camundongos SCID , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Células Tumorais Cultivadas , Virulência , Replicação Viral/genética
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