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1.
Hum Reprod Open ; 2022(4): hoac042, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36382009

RESUMO

STUDY QUESTION: In a non-commercial national gamete donation programme, do the motivations and personality characteristics of candidate sperm and oocyte donors differ according to their parenthood status? SUMMARY ANSWER: Moderate differences exist between non-parent and parent candidate donors in motivations for gamete donation and representations as well as in personality characteristics. WHAT IS KNOWN ALREADY: Several studies have analysed the motivations and experiences of oocyte or sperm donors, but mainly in countries where gamete donation is a commercial transaction, and very few studies have reported results of personality traits using personality inventory tests. No study has specifically investigated the motivations and personality characteristics of candidate gamete donors according to parenthood status. STUDY DESIGN SIZE DURATION: A prospective study was carried out including 1021 candidate donors from 21 centres (in university hospitals) of the national sperm and egg banking network in France between November 2016 and December 2018. PARTICIPANTS/MATERIALS SETTING METHODS: In total, 1021 candidate gamete donors were included in the study. During their first visit, male (n = 488) and female candidate donors (n = 533) completed a questionnaire on sociodemographic characteristics, their motivations for donation and their representations of donation, infertility and family. Secondly, a NEO Personality Inventory (NEO-PI-R) exploring the Big Five personality traits was completed online. Results were compared between parent and non-parent candidate donors. MAIN RESULTS AND THE ROLE OF CHANCE: Altruistic values were the principal motive for donation irrespective of parenthood status. Reassurance about their fertility or preservation of sperm for future use was more often reported in non-parent than in parent candidate donors. With regard to representation of gamete donation or of the family, independently of their parenthood status, candidate donors more frequently selected social rather than biological representations. Mean personality characteristics were in the normal range. Non-parent candidate donors had higher scores on openness and depression than parents, while parent candidate donors appeared more social than non-parents. LIMITATIONS REASONS FOR CAUTION: The personality characteristics inventory was not completed by all candidate donors included in the study. However, family status did not differ between the two groups (NEO-PI-R completed (n = 525) or not), while the group who completed the NEO-PI-R had a higher educational level. This national study was performed in a country where gamete donation is subject to strict legislation. WIDER IMPLICATIONS OF THE FINDINGS: In a global context where reproductive medicine is commercialized and gamete donor resources are limited, this study found that altruism and social representations of gamete donation and family are the main motivations for gamete donation in a country which prohibits financial incentive. These findings are relevant for health policy and for gamete donation information campaigns. STUDY FUNDING/COMPETING INTERESTS: Grant from the Agence de la Biomédecine, France. The authors have nothing to disclose related to this study. TRIAL REGISTRATION NUMBER: N/A.

2.
Blood ; 137(6): 826-829, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32976551

RESUMO

Sperm parameters are known to be impaired in men with sickle cell disease (SCD). Although treatment with hydroxyurea (HU) has an impact on sperm quality, sperm preservation is impossible before puberty. This study's primary objective was to analyze and compare sperm parameters in male patients with SCD exposed (or not) to HU before puberty. Twenty-six sperm samples from 15 patients (median age, 17 years; range, 16-23) treated with HU during childhood were compared with 46 samples from 23 HU-naïve patients (20 years; 16-24). The median age at HU initiation was 6 years (1-14 years), the median duration of HU treatment was 4 years (0.5-10), and the mean dose of HU was 22.4 ± 3.7 mg/kg per day. Although we observed substantial quantitative and qualitative semen abnormalities in all patients, there were no significant differences in semen volume, sperm concentration, total sperm count, or spermatozoa motility, morphology, and vitality between the HU-exposed and HU-naïve groups. At the time of the semen analysis, 100% of the patients in the HU-exposed group and 52% of the patients in the HU-naïve group received transfusion therapy. The specific effect of HU on spermatogenesis in very young infants and the putative value of transfusion for reversing the toxicity of HU warrant further investigation.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/efeitos adversos , Hidroxiureia/efeitos adversos , Infertilidade Masculina/induzido quimicamente , Puberdade , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Síndrome Torácica Aguda/epidemiologia , Síndrome Torácica Aguda/etiologia , Adolescente , Fatores Etários , Anemia Falciforme/complicações , Anemia Falciforme/fisiopatologia , Anemia Falciforme/terapia , Antidrepanocíticos/administração & dosagem , Antidrepanocíticos/uso terapêutico , Arteriopatias Oclusivas/epidemiologia , Arteriopatias Oclusivas/etiologia , Transfusão de Sangue , Criança , Pré-Escolar , Terapia Combinada , Humanos , Hidroxiureia/administração & dosagem , Hidroxiureia/uso terapêutico , Lactente , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Adulto Jovem
3.
Hum Reprod ; 31(7): 1508-14, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27165623

RESUMO

STUDY QUESTION: In couples who have chosen and confirmed the fate of surplus frozen embryos, which factors influence their decision, with a special emphasis on their symbolic representation of the embryo(s)? SUMMARY ANSWER: Embryo representation and gamete donation use significantly influence the fate of surplus cryopreserved embryos. WHAT IS KNOWN ALREADY: Previous studies report difficulties for couples to decide whether or not to continue storing their frozen embryo(s) and different factors have been already highlighted which influence their decision, including embryo conceptualization, information and support provided by the medical institution, quality of embryo(s) and life events. Little is known, however, about couples who definitely decided to stop their parental project and finalized the process of decision-making about the fate of their cryopreserved embryo(s). STUDY DESIGN, SIZE, DURATION: This prospective study was conducted over a period of 3 years (2007-2010) and included IVF/ICSI patients with surplus frozen embryos, who made a final embryo disposition decision. Among the 280 eligible IVF/ICSI patients, 247 agreed to participate in the study. According to the available options, 91 persons chose to 'stop cryopreservation', 77 chose donation to 'research' and 48 'embryo donation' to infertile couples. Furthermore, 31 participants who chose embryo donation for a parental project were refused by the center as not compatible with their mandatory medical conditions. Among them, 27 participants then selected donation to research as a new option and were included in a fourth group: 'donation to research after Refusal of Embryo Donation for parental project' or 'research-RED' (n = 27). Four participants chose 'stop cryopreservation', however, given the small number of subjects this latter group was not included in the analysis. In all, 243 participants who made a final choice concerning the fate of their cryopreserved embryos were included in this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were sent a letter of invitation to a semi-structured interview of 30 min with a psychologist. Interviews were conducted separately for each partner, including a questionnaire with a common part and a specific part, according to the chosen option, and allowing a quantitative evaluation. A multivariate logistic regression model was used to assess the link between their embryo representation and their decision about their embryos' fate. MAIN RESULTS AND THE ROLE OF CHANCE: After adjustment for age, gender, gamete donation, number of children and the different embryo representations, a choice to 'stop cryopreservation' is more frequent if the embryo is represented as a child [odds ratio (OR) adjusted = 3.29, 95% confidence interval (CI) = 1.62-6.66], P = 0.0009. Representing the embryo as a project prompts patients to choose 'donation to research' [OR adjusted = 3.76, 95% CI = 1.56-9.06], P = 0.0032. Respondents are more likely to choose 'embryo donation' if they represent the embryo as a potential person [OR adjusted = 3.77, 95% CI = 1.45-9.80], P = 0.0064. Furthermore, patients who benefited from gamete donation are ∼10 times more likely to donate their embryos to another couple [OR adjusted = 10.62, 95% CI = 3.99-28.30], P < 0.0001. For more than half the participants (57%) the decision-making was easy, however, deciding to stop cryopreservation was significantly more difficult than choosing research or embryo donation (P < 0.0001). LIMITATIONS, REASONS FOR CAUTION: Socio-economic status, moral and religious affiliations are known to influence the choice of couples but analyzing these factors was not an aim of the present study. WIDER IMPLICATIONS OF THE FINDINGS: When couples definitely decide to stop their parental project, the embryo symbolic representation remains the main factor that influences the fate of their frozen embryo(s). Moreover, this representation can evolve when influenced by external events and information provided. In order to support patients who are making this difficult decision, it could be helpful to explore this symbolic representation early in the IVF/ICSI procedure, before surplus embryo freezing, as a new tool enhancing the accuracy of counseling. STUDY FUNDING/COMPETING INTERESTS: this study was supported by a grant from the 'Agence de la biomedicine (ABM)', the national regulatory ART agency, under the authority of the French Ministry of Health. The authors have no conflict of interest to declare.


Assuntos
Destinação do Embrião/estatística & dados numéricos , Adulto , Comportamento de Escolha , Tomada de Decisões , Destinação do Embrião/psicologia , Pesquisas com Embriões , Feminino , Humanos , Estudos Prospectivos , Técnicas de Reprodução Assistida/psicologia
4.
Cytometry B Clin Cytom ; 88(2): 120-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25220539

RESUMO

BACKGROUND: Because cigarette smoke is a powerful ROS producer, we hypothesized that the spermatozoa of smokers would be more at risk of having increased DNA fragmentation than spermatozoa of non-smoking men. METHODS: A cross-sectional study was performed on consenting smokers and non-smokers, consulting in an infertility clinic for routine sperm analysis. The application of a novel TUNEL assay coupled to a vitality marker, LIVE/DEAD®, allowed both DNA fragmentation and viability measurement within spermatozoa of participants to be analyzed by flow cytometry. RESULTS: The coupled vitality-DNA fragmentation analysis revealed that non-smokers and smokers, respectively presented medians of 3.6% [0.6-36.8] and 3.3% [0.9-9.6] DNA fragmented spermatozoa among the living spermatozoa population (P > 0.05). CONCLUSION: No deleterious effect of smoking on spermatozoa was found in our study. More studies concerning potential mutagenic capacities of cigarette smoke on spermatozoa are necessary. In addition, the coupled vitality-DNA fragmentation analysis may orient Assisted Reproductive Technology teams when confronted with patients having a high percentage of DNA-fragmented living spermatozoa.


Assuntos
Fragmentação do DNA , Citometria de Fluxo/métodos , Análise do Sêmen/métodos , Fumar/patologia , Espermatozoides/patologia , Adolescente , Adulto , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos , Espermatozoides/fisiologia , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-25175858

RESUMO

Background: Because cigarette smoke is a powerful ROS producer, we hypothesized that the spermatozoa of smokers would be more at risk of having increased DNA fragmentation than spermatozoa of non-smoking men. Methods: A Cross-Sectional Study was performed on consenting smokers and non-smokers, consulting in an infertility clinic for routine sperm analysis. The application of a novel TUNEL assay coupled to a vitality marker, LIVE/DEAD®, allowed both DNA fragmentation and viability measurement within spermatozoa of participants to be analyzed by flow cytometry. Results: The coupled vitality-DNA fragmentation analysis revealed that non-smokers and smokers respectively presented medians of 3.6% [0.6-36.8] and 3.3% [0.9-9.6] DNA fragmented spermatozoa among the living spermatozoa population (p>0.05). Conclusion: No deleterious effect of smoking on spermatozoa was found in our study. More studies concerning potential mutagenic capacities of cigarette smoke on spermatozoa are necessary. In addition, the coupled vitality-DNA fragmentation analysis may orient Assisted Reproductive Technologies teams when confronted with patients having a high percentage of DNA-fragmented living spermatozoa. © 2014 Clinical Cytometry Society.

6.
J Assist Reprod Genet ; 30(6): 827-33, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23652788

RESUMO

INTRODUCTION: Temozolomide is an oral alkylating agent with proven efficacy in recurrent high-grade glioma. The antitumour activity of this molecule is attributed to the inhibition of replication through DNA methylation. However, this methylation may also perturb other DNA-dependent processes, such as spermatogenesis. The ability to father a child may be affected by having this treatment. Here we report a pregnancy and a baby born after 6 cures of temozolomide. METHODS: The quality of gametes of the father has been studied through these cures and after the cessation of treatment. Sperm parameters, chromosomal content and epigenetic profiles of H19, MEST and MGMT have been analysed. RESULTS: Sperm counts decrease significantly and hypomethylation of the H19 locus increase with time even staying in the normal range. CONCLUSION: This is the first report of an epigenetic modification in sperm after temozolomide treatment suggesting a potential risk for the offspring. A sperm cryopreservation before the initiation of temozolomide treatment should be recommended.


Assuntos
Dacarbazina/análogos & derivados , Células Germinativas/efeitos dos fármacos , Glioma/tratamento farmacológico , Espermatozoides/efeitos dos fármacos , Adulto , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Epigênese Genética/genética , Feminino , Glioma/complicações , Humanos , Masculino , Gravidez , Proteínas/metabolismo , RNA Longo não Codificante/metabolismo , Espermatogênese/efeitos dos fármacos , Espermatozoides/citologia , Temozolomida , Proteínas Supressoras de Tumor/metabolismo
7.
Gynecol Obstet Fertil ; 39(9): 525-8, 2011 Sep.
Artigo em Francês | MEDLINE | ID: mdl-21835669

RESUMO

Klinefelter syndrome is defined by the presence of a supernumerary X chromosome in a phenotypic male. It is the most frequent gonosomic anomaly in infertile men with an incidence of 0.1 to 0.2% in newborn males. The presence of an additional X chromosome induces spermatogenic failure but when gametes are present, they are usually normal. The risk of transmission of the chromosomal anomaly remains low. In the literature, only one 47,XXY foetus resulting from more than a hundred births from fathers with Klinefelter syndrome, has been reported. One can estimate, that a TESE performed in half of the patients with non-mosaic 47,XXY will be positive and may enable IVF/ICSI to be achieved.


Assuntos
Síndrome de Klinefelter/genética , Síndrome de Klinefelter/fisiopatologia , Espermatogênese/genética , Espermatozoides/fisiologia , Aberrações Cromossômicas/embriologia , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/terapia , Cariotipagem , Masculino , Injeções de Esperma Intracitoplásmicas , Espermatozoides/ultraestrutura
8.
Reprod Biomed Online ; 22(3): 277-83, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21269879

RESUMO

Hypogonadotrophic hypogonadism (HH) is characterized by deficient gonadotrophin secretion, resulting from pituitary or hypothalamic defects. In order to induce spermatogenesis, HH patients are treated with commercially available gonadotrophins. As far as is known, quality and genetic integrity of induced sperm cells have never been investigated, although they represent an important issue, since the ultimate goal of this treatment is to have competent spermatozoa in order to achieve paternity. In order to evaluate the nuclear integrity of induced sperm cells, sperm samples from treated HH patients were compared with sperm samples from normospermic control donors. Sperm cells were analysed by fluorescence in-situ hybridization, using probes specific for chromosomes 13, 21, 18, X and Y, and by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling assay. Results showed that the rate of aneuploid and diploid sperm cells in patients was not statistically different from controls and that the rate of sperm cells with fragmented DNA was within the normal values. Spermatozoa obtained by gonadotrophin treatment in HH patients are likely to have a balanced chromosomal content and a normal DNA integrity but this conclusion needs to be confirmed by further studies dealing with a greater number of patients.


Assuntos
Cromossomos Humanos/ultraestrutura , Gonadotropinas/farmacologia , Hipogonadismo/tratamento farmacológico , Análise do Sêmen/estatística & dados numéricos , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Gonadotropinas/uso terapêutico , Humanos , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Masculino , Razão de Masculinidade
9.
Gynecol Obstet Fertil ; 37(10): 796-802, 2009 Oct.
Artigo em Francês | MEDLINE | ID: mdl-19766037

RESUMO

OBJECTIVE: Despite normal sperm parameters, 5% of in vitro fertilization (IVF) attempts result in an unpredictable failure of fertilization. In 56% of the cases, there is no obvious oocyte anomaly, but lack of sperm binding to the zona pellucida. This study aims to contribute to clarify the male molecular causes of failures in IVF, which are undetected by classical sperm analysis. PATIENTS AND METHODS: The spermatic proteomic profiles of patients, with a complete failure of fertilization and no spermatozoa bound to the zona pellucida, is compared to controls (patients with normal fertilization and cleavage rates after a classical IVF for tubal indication). All samples are analysed by 2 Dimensional Electrophoresis-Differential In Gel Electrophoresis (2DE-DIGE) after being divided into three fractions according to their isoelectric point (acid, intermediate and basic). RESULTS: Fourteen proteins differentially expressed between all the cases and all the controls were highlighted. Twelve of these proteins were identified by mass spectrometry (six from the acid fraction and six from the basic fraction). Two of these proteins may have an interest in gametic interaction: the laminin receptor LR67 and the L-xylulose reductase. DISCUSSION AND CONCLUSION: More investigation is needed to understand the involvement of the identified proteins in the IVF fertilization failure of the infertile patients in this study.


Assuntos
Fertilização in vitro , Espermatozoides/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Espectrometria de Massas , Proteômica , Receptores de Laminina/metabolismo , Desidrogenase do Álcool de Açúcar/metabolismo , Falha de Tratamento
10.
Gynecol Obstet Fertil ; 37(9): 712-9, 2009 Sep.
Artigo em Francês | MEDLINE | ID: mdl-19682941

RESUMO

Performance and security questions in human oocyte cryopreservation have been taking researchers for about two decades. Oocytes are usually frozen at metaphase II. Immature oocytes cryopreservation is still a research alternative. Two techniques are currently available for oocyte cryopreservation: slow freezing and vitrification. Experimental data suggest that vitrification has less impact on oocyte physiology than classical slow freezing. After slow freezing of mature oocytes, survival and fertilization rates reach 70 to 80% whereas cleavage rates are around 90%, leading to five implantations and 1.2 births per 100 thawed oocytes. After vitrification of mature oocytes, survival and cleavage rates reach 90% leading to 11 implantations and 1.8 births per 100 thawed oocytes. The obstetrical and neonatal prognosis of these pregnancies is reassuring. No increased risk of congenital anomalies has been observed. However, further evaluation is needed to guarantee the safety of cryopreservation procedures. Immature oocyte cryopreservation is not currently perfected but some indications appear of great interest.


Assuntos
Criopreservação/métodos , Oócitos/fisiologia , Sobrevivência Celular , Feminino , Humanos , Metáfase , Oócitos/citologia , Técnicas de Reprodução Assistida
11.
Mol Hum Reprod ; 13(7): 461-4, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17494104

RESUMO

In elongating spermatids, human sperm chromatin undergoes a complex compaction in which the transition proteins are extensively replaced by the protamine proteins. Several human studies demonstrate that expression of the protamine proteins is altered in some men with male infertility. For this study, we screened the PRM1 (protamine 1) gene for mutations in a large cohort of 281 men seeking infertility treatment. We identified the c.102G>T transversion that results in an p.Arg34Ser amino acid change in two men. One of these patients presented with oligozoospermia associated with increased sperm DNA fragmentation. The second individual was normospermic but together with his partner sought treatment for idiopathic couple infertility. We also identified a novel missense mutation (c.119G>A, p.Cys40Tyr) in a man with oligoasthenozoospermia. These mutations were not observed in control populations. Interestingly, we also detected variants both 5' and 3' to the PRM1 open-reading frame specifically in infertile individuals. Four individuals with unexplained severe oligozoospermia were heterozygote for a c.-107G>C change that is located at -15 bp from the transcription initiation site of the gene. This mutation may influence PRM1 expression. In addition, a c.*51G>C variant was detected in the 3'UTR of PRM1 specifically in a man with severe oligoasthenozoospermia.


Assuntos
Infertilidade Masculina/genética , Protaminas/genética , Sequência de Bases , Análise Mutacional de DNA , Heterozigoto , Humanos , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto
12.
Mol Hum Reprod ; 13(1): 55-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17077110

RESUMO

No phenotypic effect is observed in most inversion heterozygotes. However, reproductive risks may occur in the form of infertility, spontaneous abortions or chromosomally unbalanced children as a consequence of meiotic recombination between inverted and non-inverted chromosomes. An odd number of crossovers within the inverted segment results in gametes bearing recombinant chromosomes with a duplication of the region outside of the inversion segment of one arm and a deletion of the terminal segment of the other arm [dup(p)/del(q) and del(p)/dup(q)]. Using fluorescence in-situ hybridization (FISH), the chromosome segregation of a pericentric inversion of chromosome 1 was studied in spermatozoa of a inv(1)(p22q42) heterozygous carrier. Three-colour FISH was performed on sperm samples using a probe mixture consisting of chromosome 1p telomere-specific probe, chromosome 1q telomere-specific probe and chromosome 18 centromere-specific alpha satellite DNA probe. The frequency of the non-recombinant product was 80.1%. The frequencies of the two types of recombinants carrying a duplication of the short arm and a deletion of the long arm, and vice versa, were respectively 7.6 and 7.2%, and these frequencies were not statistically significant from the expected ratio of 1:1. Sperm-FISH allows the further understanding of segregation patterns and their effect on reproductive failure and allows an accurate genetic counselling.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 1 , Hibridização in Situ Fluorescente/métodos , Infertilidade Masculina/genética , Espermatozoides/patologia , Adulto , Humanos , Infertilidade Masculina/patologia , Masculino , Modelos Genéticos , Recombinação Genética
13.
Hum Reprod ; 21(6): 1484-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16484311

RESUMO

BACKGROUND: Sperm donors represent an appropriate population for evaluating the frequency of chromosomal abnormalities in phenotypically normal and fertile adult males. METHODS: A large multicentric retrospective study was made within the French CECOS (Centre d'Etude et de Conservation des ufs et du Sperme) for collecting cytogenetic, biological and familial data in sperm donors over a 25-year period. RESULTS: As a whole, 10,202 karyotypes have been recorded. Thirty-eight karyotype aberrations (0.37%) have been diagnosed including 21 balanced chromosomal rearrangements (0.2%). These results are in agreement with those obtained in most large-scale studies performed in unselected newborns. Semen parameters were known for all men carrying an abnormal karyotype and showed normal sperm counts, suggesting that these types of chromosomal aberrations have no or poor consequences on spermatogenesis. Available familial data did not reveal any particular history of malformations, mental retardation or fetal losses. CONCLUSION: This study is the first large-scale cytogenetic study made in normal and fertile males and shows that the frequency of chromosomal aberrations is not influenced by a previous normal fertility or by an uneventful familial history when compared to that found at birth.


Assuntos
Aberrações Cromossômicas , Espermatozoides , Transtornos Cromossômicos/genética , Fertilidade , Humanos , Cariotipagem , Masculino , Fenótipo , Prevalência , Estudos Retrospectivos , Contagem de Espermatozoides , Fatores de Tempo , Doadores de Tecidos
15.
J Steroid Biochem Mol Biol ; 66(5-6): 319-26, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9749837

RESUMO

The regulation of the androgen receptor (AR) expression was studied using immunocytochemical and Western blot techniques on separate cultures of epithelial cells (PNT2) and fibroblasts of human prostate. In both cell types, immunocytochemistry revealed both nuclear and cytoplasmic staining. Treatment with DHT (5 x 10(-9) M) increased both the intensity of nuclear staining and the number of cells stained. The increase, observed after DHT treatment was markedly decreased by cyproterone acetate (5 x 10(-7) M), confirming a direct action of DHT via the AR. This autoregulation of AR was confirmed by Western blot, and seems to involve transcription and protein synthesis, since it was suppressed by actinomycin D and cycloheximide. In fibroblasts, known to contain an estrogen receptor, estradiol treatment (5 x 10(-7) M) also increases the AR immunostaining. In addition, coculture studies show that epithelial cells require the presence of fibroblasts for optimal expression of the AR. These results demonstrate that prostate epithelial cells and fibroblasts have retained in culture, an hormonal sensitivity correlated with the presence of specific receptors and can serve as a model for the study of hormone action in this tissue in normal or pathological conditions.


Assuntos
Di-Hidrotestosterona/farmacologia , Estradiol/farmacologia , Próstata/metabolismo , Receptores Androgênicos/biossíntese , Antagonistas de Androgênios/farmacologia , Núcleo Celular/química , Células Cultivadas , Técnicas de Cocultura , Cicloeximida/farmacologia , Acetato de Ciproterona/farmacologia , Citoplasma/química , Dactinomicina/farmacologia , Células Epiteliais/metabolismo , Antagonistas de Estrogênios/farmacologia , Fibroblastos/metabolismo , Homeostase , Humanos , Masculino , Inibidores da Síntese de Ácido Nucleico/farmacologia , Próstata/citologia , Inibidores da Síntese de Proteínas/farmacologia , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia
16.
Prostate ; 32(3): 155-63, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9254894

RESUMO

BACKGROUND: Whereas the embryological development of the human prostate is clearly dependent on steroid 5 alpha-reductase (5 alpha-R) type 2 expression, the respective expression of the two known isoforms (types 1 and 2) of 5 alpha-R in the adult human prostate remains unclear. METHODS: 5 alpha-R isoform mRNA expression (Northern blots and reverse transcriptase-polymerase chain reaction [RT-PCR]) and enzyme activity were studied in immortalized epithelial cells (NE) and in fibroblasts from normal (NF) or hyperplastic (BPHF) human prostates. RESULTS: 5 alpha-R activity (fmol/microgram DNA/hr) was 1.43 +/- 0.5 in NE, 10.7 +/- 4.7 in NF, and 79 +/- 37 in BPHF. mRNAs for both 5 alpha-R isoforms were expressed in the three cell types, as shown by Northern blot and RT-PCR analysis. LY306089, a selective 5 alpha-R type 1 inhibitor, strongly inhibited 5 alpha-R activity in all cell types (IC50: 10 nM), confirming the predominant expression of 5 alpha-R type 1 in these cells. Finasteride, a 5 alpha-R type 2 inhibitor, was less efficient (IC50: 45, 35, and 65 nM in NE, NF, and BPHF, respectively). In addition, the inhibition by finasteride decreased with serial subculture in NF only, suggesting an effect of age in culture on the expression of 5 alpha-R type 2 in these cells. SKF105657, also a 5 alpha-R type 2 inhibitor, was a poor inhibitor in this system. CONCLUSIONS: These studies demonstrate that human prostate cells in culture express both isoforms of 5 alpha-R and suggest a balance in the expression of the two isoforms as a function of various regulatory factors.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/análise , Regulação Enzimológica da Expressão Gênica , Isoenzimas/análise , Próstata/enzimologia , Hiperplasia Prostática/enzimologia , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Inibidores de 5-alfa Redutase , Androstadienos/farmacologia , Sequência de Bases , Benzoquinonas/farmacologia , Northern Blotting , Linhagem Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Células Epiteliais , Epitélio/enzimologia , Epitélio/patologia , Fibroblastos/citologia , Fibroblastos/enzimologia , Fibroblastos/patologia , Finasterida/farmacologia , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Masculino , Oligonucleotídeos/análise , Oligonucleotídeos/química , Oligonucleotídeos/genética , Reação em Cadeia da Polimerase , Próstata/citologia , Próstata/patologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , RNA Mensageiro/análise , RNA Mensageiro/química , RNA Mensageiro/genética
17.
J Steroid Biochem Mol Biol ; 58(2): 235-42, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8809206

RESUMO

The prostate gland depends on androgens for its development and the maintainance of its differentiated structures and secretory function. We have characterized the metabolic pathways of testosterone in isolated epithelial (NE) and fibroblast cultured cells from normal (NF) and hyperplastic (BPHF) prostates, in order to provide a tool for the study of androgen function in the prostate in defined conditions. In NE, 5 alpha-reductase (5 alpha-R) is the predominant metabolic pathway whereas in NF 17 beta-hydroxysteroid dehydrogenase (17 beta-OHSDHase) is the main activity. However, 5 alpha-R in NF is 5-10-fold higher than in NE. Furthermore, a striking increase in both enzyme activities is observed in fibroblasts from hyperplastic prostates (5 alpha-R x 8; 17 beta-OHSDHase x 250 relative to NF). delta 4-androstenedione could serve as a reservoir for testosterone or could be a tentative protective mechanism directing testosterone metabolism towards an inactive molecule. In conclusion, human epithelial and stromal cells maintain in culture their main metabolic characteristics. The knowledge derived from these studies should facilitate the reconstitution and analysis of their interactions, which in vivo may modify their respective metabolism.


Assuntos
Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Testosterona/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Células Cultivadas , Células Epiteliais , Epitélio/metabolismo , Fibroblastos/metabolismo , Humanos , Masculino , Próstata/citologia , Hiperplasia Prostática/patologia , Fatores de Tempo
18.
J Clin Endocrinol Metab ; 81(5): 1989-93, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8626870

RESUMO

Dihydrotestosterone (DHT), the 5 alpha-reduced metabolite of testosterone, is the active molecule triggering androgen action, and 5 alpha-reductase (5 alpha-R), the enzyme converting testosterone to DHT, is a key step in this mechanism. Skin, like prostate, is a DHT- dependent tissue. Our laboratory demonstrated, many years ago, that 5 alpha-R in external genitalia was not regulated by androgens, whereas it was androgen dependent in public skin. As two genes, 5 alpha-R types 1 and 2, encoding for 5 alpha-R enzymes have been recently cloned, we undertook the present study to determine whether the two enzymes we had postulated on the basis of regulation studies were coincident with the cloned isoforms. The expression of the two isoforms was studied in genital and pubic skin fibroblasts from normal men, normal women, and hirsute patients. Messenger ribonucleic acid analysis, using Northern blot and RT-PCR techniques, indicated that both 5 alpha-R1 and -2 messenger ribonucleic acids are expressed in genital skin as well as in public skin fibroblasts. In contrast, studies using specific inhibitors of 5 alpha-R1 (LY306089) and 5 alpha-R2 (finasteride) showed that 5 alpha-R2 is predominant in pubic skin of normal men, normal women, and hirsute patients. These data raise the question of the possible use of specific 5 alpha-R1 inhibitors in the treatment of idiopathic hirsutism.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Expressão Gênica , Genitália/enzimologia , Hirsutismo/enzimologia , Pele/enzimologia , Inibidores de 5-alfa Redutase , Northern Blotting , Inibidores Enzimáticos/farmacologia , Feminino , Fibroblastos/enzimologia , Humanos , Masculino , Reação em Cadeia da Polimerase , Osso Púbico , Sínfise Pubiana , RNA Mensageiro/análise
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