1
|
Zúñiga LM, Andrade JC, Fábrega-Guerén F, Orihuela PA, Velásquez EV, Vidal EA, Gutiérrez RA, Morales P, Gómez-Silva B, Croxatto HB. Mating induces early transcriptional response in the rat endosalpinx: the role of TNF and RA. Reproduction 2021; 161:43-59. [PMID: 33112288 DOI: 10.1530/rep-20-0190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 10/13/2020] [Indexed: 11/08/2022]
Abstract
During mating, males provide not only the spermatozoa to fertilize the oocyte but also other stimuli that are essential for initiating and maintaining the reproductive programme in females. In the mammalian oviduct, mating regulates sperm storage, egg transport, fertilization, early embryonic development, and oestradiol metabolism. However, the main molecules underlying these processes are poorly understood. Using microarray analyses, we identified 58 genes that were either induced or repressed by mating in the endosalpinx at 3 h post-stimulus. RT-qPCR confirmed that mating downregulated the expression of the Oas1h and Prim1 genes and upregulated the expression of the Ceacam1, Chad, Chst10, Slc5a3 and Slc26a4 genes. The functional category 'cell-to-cell signalling and interaction' was over-represented in this gene list. Network modelling identified TNF and all-trans retinoic acid (RA) as upstream regulators of the mating-induced transcriptional response, which was confirmed by intraoviductal injection of TNF or RA in unmated rats. It partially mimicked the transcriptional effect of mating in the rat endosalpinx. Furthermore, mating decreased RA levels in oviductal fluid, and RA-receptor-gamma (RARG) exhibited a nuclear location in oviductal epithelium in both unmated and mated rats, indicating RA-RARG transcriptional activity. In conclusion, the early transcriptional response regulated by mating in the rat endosalpinx is mediated by TNF and RA. These signalling molecules regulate a cohort of genes involved in 'cell-to-cell signalling and interactions' and merit further studies to understand the specific processes activated in the endosalpinx to sustain the events that occur in the mammalian oviduct early after mating.
Collapse
Affiliation(s)
- Lidia M Zúñiga
- Laboratorio de Bioquímica, Departamento Biomédico, and Centre for Biotechnology and Bioengineering (CeBiB), Universidad de Antofagasta, Antofagasta, Chile
| | - Juan-Carlos Andrade
- Laboratorio de Biología de la Reproducción, Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile
| | - Francisca Fábrega-Guerén
- Laboratorio de Bioquímica, Departamento Biomédico, and Centre for Biotechnology and Bioengineering (CeBiB), Universidad de Antofagasta, Antofagasta, Chile
| | - Pedro A Orihuela
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Ethel V Velásquez
- Departamento de Tecnologías Nucleares, Comisión Chilena de Energía Nuclear, Santiago, Chile
| | - Elena A Vidal
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- ANID, Programa Iniciativa Científica Milenio, Millennium Institute for Integrative Biology iBio, Santiago, Chile
| | - Rodrigo A Gutiérrez
- FONDAP Centre for Genome Regulation, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- ANID, Programa Iniciativa Científica Milenio, Millennium Institute for Integrative Biology iBio, Santiago, Chile
| | - Patricio Morales
- Laboratorio de Biología de la Reproducción, Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile
| | - Benito Gómez-Silva
- Laboratorio de Bioquímica, Departamento Biomédico, and Centre for Biotechnology and Bioengineering (CeBiB), Universidad de Antofagasta, Antofagasta, Chile
| | - Horacio B Croxatto
- Instituto de Salud Pública, Facultad de Medicina, Universidad Andrés Bello, Santiago, Chile
| |
Collapse
|
2
|
Cuevas CA, Tapia-Pizarro A, Salvatierra AM, Munroe DJ, Velasquez L, Croxatto HB. Effect of single post-ovulatory administration of mifepristone (RU486) on transcript profile during the receptive period in human endometrium. Reproduction 2016; 151:331-49. [DOI: 10.1530/rep-15-0458] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/11/2016] [Indexed: 12/24/2022]
Abstract
Progesterone regulates uterine function during the luteal phase and is essential for the acquisition of endometrial receptivity. The objective of the present study was to identify endometrial transcripts whose expression is altered during the window of implantation after the administration of 200 mg of the antiprogestin mifepristone, 48 h after the LH peak (LH+2, LH+0=LH peak), and to determine the relationship of these transcripts with those regulated during the acquisition of receptivity. Endometrial samples were obtained in LH+7 from seven women of proven fertility, each one contributing with one cycle treated with placebo and another with mifepristone. Additionally, endometrial samples were obtained in LH+2 and LH+7 during a single untreated spontaneous cycle from seven normal fertile women as a reference. DNA microarrays were used to identify transcripts significantly regulated (defined as ≥2.0-fold change with false discovery rate below 1% usingt-test) with the administration of mifepristone vs placebo, or during the transition from pre-receptive to receptive (LH+2 vs LH+7). Approximately 2000 transcripts were significantly regulated in both comparisons (mifepristone vs placebo and LH+2 vs LH+7), but only 777 of them were coincident and displayed opposite regulation except for 25. The mRNA level for eight selected genes regulated by mifepristone was confirmed by real-time RT-PCR. We conclude that not all changes in endometrial transcript levels occurring in the transition from LH+2 to LH+7 seem to be regulated by the progesterone receptor and ∼37% of the genes whose transcript levels changed by effect of mifepristone could be associated with the acquisition of receptivity.
Collapse
|
3
|
Tapia-Pizarro A, Figueroa P, Brito J, Marín JC, Munroe DJ, Croxatto HB. Endometrial gene expression reveals compromised progesterone signaling in women refractory to embryo implantation. Reprod Biol Endocrinol 2014; 12:92. [PMID: 25248672 PMCID: PMC4181418 DOI: 10.1186/1477-7827-12-92] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 09/17/2014] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Endometrial function is essential for embryo implantation. The aim of this study was to analyze gene expression profiles from individual endometrial samples obtained from women with repeated implantation failure after IVF in oocyte donation programs. METHODS Seventeen volunteers were recruited: women who had previously participated as recipients in oocyte donation cycles and repeatedly exhibited implantation failure (Group A, study group, n = 5) or had at least one successful cycle (Group B, control group, n = 6) and spontaneously fertile women (Group C, normal fertility group, n = 6). An endometrial cycle was induced with exogenous estradiol (E2) and progesterone (P) and an endometrial sample was collected on the seventh day of P treatment. RESULTS Transcriptome analysis showed 82 genes with consistent differential gene expression when comparing A vs. B and A vs. C. One hundred transcripts differentially expressed in group A vs. B have been shown to be regulated by P, suggesting compromised P signaling in the endometrium. The P receptor (PR) mutation PROGINS was not detected in women from group A. Semi-quantitation of immunoreactive PRA/B, PRB and Sp1 (a transcription factor related to P signaling) in paraffin-embedded endometrial sections, did not show statistically significant differences amongst groups. However immunostaining glycodelin was significantly decreased in endometrial samples from group A. CONCLUSIONS We conclude that some cases of repeated implantation failure could be associated with an aberrant gene expression profile. Compromised P signaling might be the underlying mechanism for such endometrial gene expression deregulation in women with repeated implantation failure.
Collapse
Affiliation(s)
- Alejandro Tapia-Pizarro
- />Instituto de Investigaciones Materno Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Paula Figueroa
- />Facultad de Medicina, Universidad Mayor, Santiago, Chile
| | - Julio Brito
- />Facultad de Medicina, Universidad Mayor, Santiago, Chile
| | | | - David J Munroe
- />Advanced Technology Program, SAIC-Frederick, Inc., National Cancer Institute-Frederick, Frederick, MD 21701 USA
| | - Horacio B Croxatto
- />Center for Integrative Medicine and Innovative Sciences, Universidad Andrés Bello, Santiago, Chile
| |
Collapse
|
4
|
Brache V, Cochon L, Deniaud M, Croxatto HB. Ulipristal acetate prevents ovulation more effectively than levonorgestrel: analysis of pooled data from three randomized trials of emergency contraception regimens. Contraception 2013; 88:611-8. [PMID: 23809278 DOI: 10.1016/j.contraception.2013.05.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 05/08/2013] [Accepted: 05/16/2013] [Indexed: 12/30/2022]
Abstract
BACKGROUND The days just prior to ovulation are the most crucial for emergency contraception (EC) efficacy. Ulipristal acetate (UPA) and levonorgestrel's (LNG) capacity to inhibit follicular rupture have never been compared directly at this time of the cycle. STUDY DESIGN Raw data from three pharmacodynamics studies with similar methodology were pooled to allow direct comparison of UPA, LNG and LNG + meloxicam's ability to prevent ovulation when administered orally in the advanced follicular phase, with a leading follicle of ≥ 18 mm. RESULTS Forty eight LNG-treated (1.5 mg) cycles, 31 LNG (1.5 mg) + meloxicam (15 mg), 34 UPA (30 mg) cycles and 50 placebo cycles were compared. Follicle rupture was delayed for at least 5 days in 14.6%, 38.7%, 58.8% and 4% of the LNG-, LNG + meloxicam-, UPA- and placebo-treated cycles, respectively. UPA was more effective than LNG and placebo in inhibiting follicular rupture (p = .0001), while LNG, when administered at this time of the cycle, was not different than placebo. The addition of meloxicam improved the efficacy of LNG in preventing follicular rupture (p = .0292 vs. LNG; p = .0001 vs. placebo; non-significant vs. UPA). UPA was effective in preventing rupture in the 5 days following treatment, even when administered at the time of the luteinizing hormone (LH) surge (UPA 79%, LNG 14% and placebo 10%). None of the treatments were effective when administered on the day of the LH peak. The median time from treatment to rupture was 6 days during the ulipristal cycles and 2 days in the placebo and LNG/LNG + meloxicam cycles (p = .0015). CONCLUSION Although no EC treatment is 100% effective in inhibiting follicular rupture when administered in the late follicular phase, UPA is the most effective treatment, delaying ovulation for at least 5 days in 59% of the cycles. LNG is not different from placebo in inhibiting follicular rupture at this advanced phase of the cycle. No treatment was effective in postponing rupture when administered on the day of LH peak.
Collapse
|
5
|
Velasquez EV, Ríos M, Ortiz ME, Lizama C, Nuñez E, Abramovich D, Orge F, Oliva B, Orellana R, Villalon M, Moreno RD, Tesone M, Rokka A, Corthals G, Croxatto HB, Parborell F, Owen GI. Concanavalin-A induces granulosa cell death and inhibits FSH-mediated follicular growth and ovarian maturation in female rats. Endocrinology 2013; 154:1885-96. [PMID: 23515285 DOI: 10.1210/en.2012-1945] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Reproductive success stems from a finely regulated balance between follicular maturation and atresia, in which the role of carbohydrate structure is poorly understood. Here, we describe for the first time a fraction of purified recombinant human FSH that is capable of bringing about the cell death of granulosa cells and preventing follicular maturation in a rat model. Further analysis by mass spectrometry revealed the presence of the lectin Concanavalin-A (Con-A) within this fraction of recombinant FSH. Using both the fractionated FSH and Con-A, the observed cell death was predominantly located to the granulosa cells. Ex vivo culture of rat follicles demonstrated that follicle degeneration occurred and resulted in the release of a denuded and deteriorated oocyte. Moreover, in vivo experiments confirmed an increase in atresia and a corresponding reduction confined to follicle in early antral stage. As a mechanism of action, Con-A reduces ovarian proliferation, Von Willebrand staining, and angiogenesis. Based on the observation that Con-A may induce granulosa cell death followed by follicle death, our results further demonstrate that follicular carbohydrate moiety is changing under the influence of FSH, which may allow a carbohydrate-binding lectin to increase granulosa cell death. The physiological consequences of circulating lectin-like molecules remain to be determined. However, our results suggest a potential exploitation of carbohydrate binding in fertility and ovarian cancer treatment. This work may shed light on a key role of carbohydrates in the still obscure physiological process of follicular selection and atresia.
Collapse
Affiliation(s)
- Ethel V Velasquez
- Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Noe G, Croxatto HB. Response to Letter to the Editor. Contraception 2012. [DOI: 10.1016/j.contraception.2012.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
7
|
Parada-Bustamante A, Croxatto HB, Cárdenas H, Orihuela PA. Differential participation of endothelin receptors in estradiol-induced oviductal egg transport acceleration in unmated and mated rats. Asian Pacific Journal of Reproduction 2012. [DOI: 10.1016/s2305-0500(13)60042-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
8
|
Vargas MF, Tapia-Pizarro AA, Henríquez SP, Quezada M, Salvatierra AM, Noe G, Munroe DJ, Velasquez LA, Croxatto HB. Effect of single post-ovulatory administration of levonorgestrel on gene expression profile during the receptive period of the human endometrium. J Mol Endocrinol 2012; 48:25-36. [PMID: 22052941 DOI: 10.1530/jme-11-0094] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hypothesis that levonorgestrel (LNG) used as an emergency contraceptive interferes with endometrial receptivity remains unproven. We compared the endometrial gene expression profile during the receptive period after administering a single dose of LNG 1.5 mg or placebo on day 1 of the luteal phase. An endometrial biopsy was done on day LH+7 or LH+8 and samples were taken from seven volunteers, each one contributing with one cycle treated with placebo and another with LNG. The expression of 20 383 genes was determined using cDNA microarrays. Real-time RT-PCR was used 1) to confirm the differences found in DNA microarray analysis and 2) to determine the effect of LNG on transcript levels of C3, C4BPα, COX2, MAOA, S100A4, and SERPINB9, known to be upregulated during receptivity, and on cPLA2α, JAK1, JNK1, CTSL1, and GSTP1, known to respond to mifepristone. Additional endometrial biopsies were done during the pre-receptive (LH+3) and receptive (LH+7) period and samples were taken from eight untreated volunteers in order to determine the changes associated with acquisition of receptivity of 14 genes. Mean levels of PAEP, TGM2, CLU, IGF2, and IL6ST mRNAs increased after administering LNG while those of HGD, SAT1, EVA1, LOC90133, ANXA1, SLC25A29, CYB5A, CRIP1, and SLC39A14 decreased. Except for the level of ANXA1 transcript, all changes remained within the range observed in untreated controls, and none of the transcripts responding to mifepristone changed in response to LNG. Post-ovulatory administration of LNG caused minimal changes in gene expression profiling during the receptive period. Neither the magnitude nor the nature or direction of the changes endorses the hypothesis that LNG interferes with endometrial receptivity.
Collapse
Affiliation(s)
- M F Vargas
- Universidad Santiago de Chile, Santiago, Chile
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Hermanny A, Bahamondes MV, Fazano F, Marchi NM, Ortiz ME, Genghini MHRR, Croxatto HB, Bahamondes L. In vitro assessment of some sperm function following exposure to levonorgestrel in human fallopian tubes. Reprod Biol Endocrinol 2012; 10:8. [PMID: 22289514 PMCID: PMC3395846 DOI: 10.1186/1477-7827-10-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 01/30/2012] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The mechanism of action of levonorgestrel (LNG) as emergency contraception (EC) remains a subject of debate and its effect on sperm function has been only partially explained. The aim of this study was to assess whether LNG at a similar dose to those found in serum following oral intake for EC could affect spermatozoa when exposed to human fallopian tubes in vitro. METHODS Fifteen mini-laparotomies were performed, the side on which ovulation occurred was recorded, and both tubes were removed and perfused with a suspension containing 1 × 10(6) motile spermatozoa, with or without LNG. Following 4-hour incubation, the tubes were sectioned to separate the isthmus and the ampulla. Each segment was flushed and the material was evaluated to quantify the number of motile sperm, the number of spermatozoa adhering to the oviductal epithelium and the acrosome reaction (AR) rate. RESULTS The addition of LNG did not significantly alter the number of recovered motile spermatozoa either at the isthmus or at the ampulla, nor did it have any effect on the number of recovered spermatozoa adhered to the human tubal epithelium. Furthermore, LNG did not affect the AR rate. No significant differences were found even when the side on which ovulation occurred was taken into account. CONCLUSIONS In a similar dose to that observed in serum following oral intake for EC, LNG had no effect on the number of motile spermatozoa recovered from the human fallopian tubes in vitro, on their adhesion to the tubal epithelium, distribution or AR rate. The possible effect of LNG as EC on sperm function remains poorly understood.
Collapse
Affiliation(s)
- Alexia Hermanny
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| | - M Valeria Bahamondes
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| | - Francisco Fazano
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| | - Nadia M Marchi
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| | | | - Maria Heloisa RR Genghini
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| | - Horacio B Croxatto
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Luis Bahamondes
- Human Reproduction Unit, Department of Obstetrics and Gynecology, School of Medicine, University of Campinas (UNICAMP), 13084-971 Campinas, SP, Brazil
| |
Collapse
|
10
|
Ríos M, Parada-Bustamante A, Velásquez LA, Croxatto HB, Orihuela PA. Participation of the oviductal s100 calcium binding protein G in the genomic effect of estradiol that accelerates oviductal embryo transport in mated rats. Reprod Biol Endocrinol 2011; 9:69. [PMID: 21605449 PMCID: PMC3115850 DOI: 10.1186/1477-7827-9-69] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Accepted: 05/23/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mating changes the mechanism by which E2 regulates oviductal egg transport, from a non-genomic to a genomic mode. Previously, we found that E2 increased the expression of several genes in the oviduct of mated rats, but not in unmated rats. Among the transcripts that increased its level by E2 only in mated rats was the one coding for an s100 calcium binding protein G (s100 g) whose functional role in the oviduct is unknown. METHODS Herein, we investigated the participation of s100 g on the E2 genomic effect that accelerates oviductal transport in mated rats. Thus, we determined the effect of E2 on the mRNA and protein level of s100 g in the oviduct of mated and unmated rats. Then, we explored the effect of E2 on egg transport in unmated and mated rats under conditions in which s100 g protein was knockdown in the oviduct by a morpholino oligonucleotide against s100 g (s100 g-MO). In addition, the localization of s100 g in the oviduct of mated and unmated rats following treatment with E2 was also examined. RESULTS Expression of s100 g mRNA progressively increased at 3-24 h after E2 treatment in the oviduct of mated rats while in unmated rats s100 g increased only at 12 and 24 hours. Oviductal s100 g protein increased 6 h following E2 and continued elevated at 12 and 24 h in mated rats, whereas in unmated rats s100 g protein increased at the same time points as its transcript. Administration of a morpholino oligonucleotide against s100 g transcript blocked the effect of E2 on egg transport in mated, but not in unmated rats. Finally, immunoreactivity of s100 g was observed only in epithelial cells of the oviducts of mated and unmated rats and it was unchanged after E2 treatment. CONCLUSIONS Mating affects the kinetic of E2-induced expression of s100 g although it not changed the cellular localization of s100 g in the oviduct after E2 . On the other hand, s100 g is a functional component of E2 genomic effect that accelerates egg transport. These findings show a physiological involvement of s100 g in the rat oviduct.
Collapse
Affiliation(s)
- Mariana Ríos
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Alexis Parada-Bustamante
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Luis A Velásquez
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
| | - Horacio B Croxatto
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
- Millennium Institute for Fundamental and Applied Biology, Santiago, Chile
| | - Pedro A Orihuela
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
| |
Collapse
|
11
|
Noé G, Croxatto HB, Salvatierra AM, Reyes V, Villarroel C, Muñoz C, Morales G, Retamales A. Response to the Letter to the Editor. Contraception 2011. [DOI: 10.1016/j.contraception.2010.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Tapia A, Vilos C, Marín JC, Croxatto HB, Devoto L. Bioinformatic detection of E47, E2F1 and SREBP1 transcription factors as potential regulators of genes associated to acquisition of endometrial receptivity. Reprod Biol Endocrinol 2011; 9:14. [PMID: 21272326 PMCID: PMC3040129 DOI: 10.1186/1477-7827-9-14] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 01/27/2011] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The endometrium is a dynamic tissue whose changes are driven by the ovarian steroidal hormones. Its main function is to provide an adequate substrate for embryo implantation. Using microarray technology, several reports have provided the gene expression patterns of human endometrial tissue during the window of implantation. However it is required that biological connections be made across these genomic datasets to take full advantage of them. The objective of this work was to perform a research synthesis of available gene expression profiles related to acquisition of endometrial receptivity for embryo implantation, in order to gain insights into its molecular basis and regulation. METHODS Gene expression datasets were intersected to determine a consensus endometrial receptivity transcript list (CERTL). For this cluster of genes we determined their functional annotations using available web-based databases. In addition, promoter sequences were analyzed to identify putative transcription factor binding sites using bioinformatics tools and determined over-represented features. RESULTS We found 40 up- and 21 down-regulated transcripts in the CERTL. Those more consistently increased were C4BPA, SPP1, APOD, CD55, CFD, CLDN4, DKK1, ID4, IL15 and MAP3K5 whereas the more consistently decreased were OLFM1, CCNB1, CRABP2, EDN3, FGFR1, MSX1 and MSX2. Functional annotation of CERTL showed it was enriched with transcripts related to the immune response, complement activation and cell cycle regulation. Promoter sequence analysis of genes revealed that DNA binding sites for E47, E2F1 and SREBP1 transcription factors were the most consistently over-represented and in both up- and down-regulated genes during the window of implantation. CONCLUSIONS Our research synthesis allowed organizing and mining high throughput data to explore endometrial receptivity and focus future research efforts on specific genes and pathways. The discovery of possible new transcription factors orchestrating the CERTL opens new alternatives for understanding gene expression regulation in uterine function.
Collapse
Affiliation(s)
- Alejandro Tapia
- Instituto de Investigaciones Materno Infantil (IDIMI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Cristian Vilos
- Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | | | - Horacio B Croxatto
- Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Santiago, Chile
| | - Luigi Devoto
- Instituto de Investigaciones Materno Infantil (IDIMI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Centro FONDAP de Estudios Moleculares de la Célula (CEMC), Santiago, Chile
| |
Collapse
|
13
|
Brache V, Cochon L, Jesam C, Maldonado R, Salvatierra AM, Levy DP, Gainer E, Croxatto HB. Immediate pre-ovulatory administration of 30 mg ulipristal acetate significantly delays follicular rupture. Hum Reprod 2010; 25:2256-63. [PMID: 20634186 DOI: 10.1093/humrep/deq157] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- V Brache
- PROFAMILIA, Nicolas de Ovando & Calle 16, Santo Domingo 10401, Dominican Republic.
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Noé G, Croxatto HB, Salvatierra AM, Reyes V, Villarroel C, Muñoz C, Morales G, Retamales A. Contraceptive efficacy of emergency contraception with levonorgestrel given before or after ovulation. Contraception 2010; 81:414-20. [DOI: 10.1016/j.contraception.2009.12.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 12/10/2009] [Accepted: 12/16/2009] [Indexed: 12/30/2022]
|
15
|
Parada-Bustamante A, Orihuela PA, Ríos M, Cuevas CA, Oróstica ML, Velásquez LA, Villalón MJ, Croxatto HB. A non-genomic signaling pathway shut down by mating changes the estradiol-induced gene expression profile in the rat oviduct. Reproduction 2009; 139:631-44. [PMID: 20032209 DOI: 10.1530/rep-09-0218] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Estradiol (E(2)) accelerates oviductal egg transport through intraoviductal non-genomic pathways in unmated rats and through genomic pathways in mated rats. This shift in pathways has been designated as intracellular path shifting (IPS), and represents a novel and hitherto unrecognized effect of mating on the female reproductive tract. We had reported previously that IPS involves shutting down the E(2) non-genomic pathway up- and downstream of 2-methoxyestradiol. Here, we evaluated whether IPS involves changes in the genomic pathway too. Using microarray analysis, we found that a common group of genes changed its expression in response to E(2) in unmated and mated rats, indicating that an E(2) genomic signaling pathway is present before and after mating; however, a group of genes decreased its expression only in mated rats and another group of genes increased its expression only in unmated rats. We evaluated the possibility that this difference is a consequence of an E(2) non-genomic signaling pathway present in unmated rats, but not in mated rats. Mating shuts down this E(2) non-genomic signaling pathway up- and downstream of cAMP production. The Star level is increased by E(2) in unmated rats, but not in mated rats. This is blocked by the antagonist of estrogen receptor ICI 182 780, the adenylyl cyclase inhibitor SQ 22536, and the catechol-O-methyltransferase inhibitor, OR 486. These results indicate that the E(2)-induced gene expression profile in the rat oviduct differs before and after mating, and this difference is probably mediated by an E(2) non-genomic signaling pathway operating on gene expression only in unmated rats.
Collapse
Affiliation(s)
- Alexis Parada-Bustamante
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, 8331010 Santiago, Chile
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Orihuela PA, Zuñiga LM, Rios M, Parada-Bustamante A, Sierralta WD, Velásquez LA, Croxatto HB. Mating changes the subcellular distribution and the functionality of estrogen receptors in the rat oviduct. Reprod Biol Endocrinol 2009; 7:139. [PMID: 19948032 PMCID: PMC2789086 DOI: 10.1186/1477-7827-7-139] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 11/30/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mating changes the mode of action of 17beta-estradiol (E2) to accelerate oviductal egg transport from a nongenomic to a genomic mode, although in both pathways estrogen receptors (ER) are required. This change was designated as intracellular path shifting (IPS). METHODS Herein, we examined the subcellular distribution of ESR1 and ESR2 (formerly known as ER-alpha and ER-beta) in oviductal epithelial cells of rats on day 1 of cycle (C1) or pregnancy (P1) using immunoelectron microscopy for ESR1 and ESR2. The effect of mating on intraoviductal ESR1 or ESR2 signaling was then explored comparing the expression of E2-target genes c-fos, brain creatine kinase (Ckb) and calbindin 9 kDa (s100g) in rats on C1 or P1 treated with selective agonists for ESR1 (PPT) or ESR2 (DPN). The effect of ER agonists on egg transport was also evaluated on C1 or P1 rats. RESULTS Receptor immunoreactivity was associated with the nucleus, cytoplasm and plasma membrane of the epithelial cells. Mating affected the subcellular distribution of both receptors as well as the response to E2. In C1 and P1 rats, PPT increased Ckb while both agonists increased c-fos. DPN increased Ckb and s100g only in C1 and P1 rats, respectively. PPT accelerated egg transport in both groups and DPN accelerated egg transport only in C1 rats. CONCLUSION Estrogen receptors present a subcellular distribution compatible with E2 genomic and nongenomic signaling in the oviductal epithelial cells of C1 and P1 although IPS occurs independently of changes in the distribution of ESR1 and ESR2 in the oviductal epithelial cells. Mating affected intraoviductal ER-signaling and induced loss of functional involvement of ESR2 on E2-induced accelerated egg transport. These findings reveal a profound influence on the ER signaling pathways exerted by mating in the oviduct.
Collapse
Affiliation(s)
- Pedro A Orihuela
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
| | - Lidia M Zuñiga
- Millennium Institute for Fundamental and Applied Biology, Santiago, Chile
| | - Mariana Rios
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - Walter D Sierralta
- Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile
| | - Luis A Velásquez
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
| | - Horacio B Croxatto
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
- Centro para el Desarrollo en Nanociencia y Nanotecnología-CEDENNA, Santiago, Chile
- Millennium Institute for Fundamental and Applied Biology, Santiago, Chile
| |
Collapse
|
17
|
Jesam C, Salvatierra AM, Schwartz JL, Croxatto HB. Suppression of follicular rupture with meloxicam, a cyclooxygenase-2 inhibitor: potential for emergency contraception. Hum Reprod 2009; 25:368-73. [PMID: 19933235 DOI: 10.1093/humrep/dep392] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND There is evidence that cyclooxygenase-2 (COX-2) inhibitors can prevent or delay follicular rupture. COX-2 inhibitors, such as meloxicam, may offer advantages over emergency contraception with levonorgestrel, such as extending the therapeutic window for up to 24 h. We assessed the effect of meloxicam administered in the late follicular phase upon ovulation in women. MATERIALS AND METHODS This was a single center, double blind, crossover study designed to assess the effects in 27 eligible women (18-40 years old, surgically sterilized with regular menstrual cycles) of meloxicam, 15 or 30 mg/day, administered orally for five consecutive days during the late follicular phase, starting when the leading follicle reached 18 mm diameter. Volunteers underwent two treatment cycles separated by one resting cycle, with randomization to dose sequence. Main outcomes were follicular rupture; serum LH, progesterone and estradiol (E2) levels; and incidence of adverse events. RESULTS Twenty-two volunteers completed the study. There were no differences between meloxicam doses in menstrual cycle length. Dysfunctional ovulation was observed in 11/22 (50%) cycles treated with 15 mg/day and 20/22 (90.9%) cycles with 30 mg/day (P = 0.0068). All women had normal luteal phase progesterone levels; mean maximal values +/- SEM were 42 +/- 4.1 and 46.8 +/- 2.6 nmol/l for 15 and 30 mg/day groups, respectively. There were no serious adverse events, and no changes in LH and E2 levels or in cycle length. CONCLUSIONS Meloxicam 30 mg given for five consecutive days in the late follicular phase is safe, effective and may be an alternative form of emergency contraception.
Collapse
Affiliation(s)
- Cristián Jesam
- Instituto Chileno de Medicina Reproductiva (ICMER), José Victorino Lastarria 29, Apt. 101, Santiago, Chile.
| | | | | | | |
Collapse
|
18
|
Andreone L, Velásquez EV, Abramovich D, Ambao V, Loreti N, Croxatto HB, Parborell F, Tesone M, Campo S. Regulation of inhibin/activin expression in rat early antral follicles. Mol Cell Endocrinol 2009; 309:48-54. [PMID: 19464342 DOI: 10.1016/j.mce.2009.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 05/07/2009] [Accepted: 05/12/2009] [Indexed: 11/18/2022]
Abstract
The aim of the present study was to determine the endocrine activity of cultured early antral follicles (EAF) isolated from prepubertal diethylstilbestrol-treated rats. The effect of steroidogenic substrates and FSH on steroid, inhibin A and B, Pro-alphaC and activin A production was evaluated. Androsterone was the predominant steroid produced by EAF. The addition of androstenedione, androstenedione+FSH and progesterone stimulated oestradiol production, whereas 25-hydroxycholesterol (25-OH-Chol) increased progesterone production. Inhibin A, B, Pro-alphaC, and activin A were produced under basal conditions. The predominance of inhibin B over inhibin A was not affected by the addition of androstenedione or progesterone. Inhibin A and activin A production was stimulated by FSH. 25-OH-Chol increased Inha, Inhba and Inhbb mRNA expression and the production of the three molecular forms of inhibins but decreased activin A production. These results show that FSH and the steroid follicular microenvironment differentially modulate the gene expression of inhibin/activin subunits, their assembly and secretion.
Collapse
Affiliation(s)
- Luz Andreone
- Centro de Investigaciones Endocrinológicas (CEDIE-CONICET), Hospital de Niños R. Gutiérrez, Gallo 1330, C1425EFD, Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Zuniga LM, Orihuela PA, Croxatto HB. Mating Modifies the Expression of Nfatc3, Nfkb1, Fos, and Jun in Endosalpinx: Possible Role in Silencing of Non-Genomic Pathway of Estradiol. Biol Reprod 2009. [DOI: 10.1093/biolreprod/81.s1.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
20
|
Tapia A, Gangi LM, Zegers-Hochschild F, Balmaceda J, Pommer R, Trejo L, Pacheco IM, Salvatierra AM, Henríquez S, Quezada M, Vargas M, Ríos M, Munroe DJ, Croxatto HB, Velasquez L. Differences in the endometrial transcript profile during the receptive period between women who were refractory to implantation and those who achieved pregnancy. Hum Reprod 2007; 23:340-51. [PMID: 18077318 DOI: 10.1093/humrep/dem319] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Gene expression profiling of normal receptive endometrium has been characterized, but intrinsic defects in endometrial gene expression associated with implantation failure have not been reported. METHODS Women who had previously participated as recipients in oocyte donation cycles and repeatedly exhibited implantation failure (Group A, study group) or had at least one successful cycle (Group B, control group) and spontaneously fertile women (Group C, normal fertility group) were recruited. All were treated with exogenous estradiol and progesterone to induce an endometrial cycle, and an endometrial biopsy was taken on the seventh day of progesterone administration. RNA from each sample was analysed by cDNA microarrays to identify differentially expressed genes between groups. RESULTS 63 transcripts were differentially expressed (>or=2-fold) between Groups A and B, of which 16 were subjected to real time RT-PCR. Eleven of these were significantly decreased in Group A with regard to Groups B and C. Among the dysregulated genes were MMP-7, CXCR4, PAEP and C4BPA. CONCLUSIONS Repeated implantation failure in some oocyte recipients is associated with an intrinsic defect in the expression of multiple genes in their endometrium. Significantly decreased levels of several transcripts in endometria without manifest abnormalities is demonstrated for the first time and shown to be associated with implantation failure.
Collapse
Affiliation(s)
- Alejandro Tapia
- Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Ortiz ME, Ortiz RE, Garfield R, Zepeda AJ, Croxatto HB. Progesterone, but not luteal estrogen, is required for the establishment of pregnancy in the new world monkey Cebus apella. Am J Primatol 2007; 69:1131-40. [PMID: 17387700 DOI: 10.1002/ajp.20408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aim of this study was to examine the requirement of luteal progesterone or luteal estrogen for the establishment of pregnancy in the Cebus monkey and to test in a primate species the synergism between RU 486 and letrozole (LTZ) found in rodents for inhibiting implantation. Exposure of target tissues to either hormone was suppressed during the mid-luteal phase of mating cycles by subcutaneous administration of the antiprogestin (RU 486), the aromatase inhibitor LTZ or the antiestrogen (ICI 182780) on days 4-7 of the luteal phase. Administration of 0.1 or 0.5 mg/kg of LTZ on days 5-7 of the luteal phase caused a profound drop in the levels of E(2) in all animals, whereas administration of ICI 182780 0.2 mg/kg on days 4-6 of the luteal phase had the opposite effect. The pregnancy rate in vehicle treated cycles of the same females was (58.3%). Treatment with RU 486, 0.8 mg/kg/day on days 5-7 of the luteal phase-induced endometrial bleeding in 3/5 mated females none of which became pregnant, whereas pregnancy was confirmed in one of the two animals that did not bled. Treatment with RU 486, 0.4 mg/kg/day alone or with LTZ on days 5-7 or ICI 182780 alone, on days 4-6 of the luteal phase failed to induce bleeding, allowing the establishment of pregnancy in 50.0-66.6% of the animals in these groups. We conclude that in Cebus monkeys, progesterone but not luteal estradiol is required for the establishment of pregnancy and that RU 486 and LTZ do not exhibit in this species the synergism found in rodents.
Collapse
Affiliation(s)
- M E Ortiz
- Unit of Reproductive Biology and Development, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
| | | | | | | | | |
Collapse
|
22
|
Parada-Bustamante A, Orihuela PA, Ríos M, Navarrete-Gómez PA, Cuevas CA, Velasquez LA, Villalón MJ, Croxatto HB. Catechol-O-Methyltransferase and Methoxyestradiols Participate in the Intraoviductal Nongenomic Pathway Through Which Estradiol Accelerates Egg Transport in Cycling Rats1. Biol Reprod 2007; 77:934-41. [PMID: 17699737 DOI: 10.1095/biolreprod.107.061622] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Estradiol (E(2)) accelerates oviductal egg transport through intraoviductal nongenomic pathways in cyclic rats and through genomic pathways in pregnant rats. This shift in pathways, which we have provisionally designated as intracellular path shifting (IPS), is caused by mating-associated signals and represents a novel and hitherto unrecognized phenomenon. The mechanism underlying IPS is currently under investigation. Using microarray analysis, we identified several genes the expression levels of which changed in the rat oviduct within 6 hours of mating. Among these genes, the mRNA level for the enzyme catechol-O-methyltransferase (COMT), which produces methoxyestradiols from hydroxyestradiols, decreased 6-fold, as confirmed by real-time PCR. O-methylation of 2-hydroxyestradiol was up to 4-fold higher in oviductal protein extracts from cyclic rats than from pregnant rats and was blocked by OR486, which is a selective inhibitor of COMT. The levels in the rat oviduct of mRNA and protein for cytochrome P450 isoforms 1A1 and 1B1, which form hydroxyestradiols, were detected by RT-PCR and Western blotting. We explored whether methoxyestradiols participate in the pathways involved in E(2)-accelerated egg transport. Intrabursal application of OR486 prevented E(2) from accelerating egg transport in cyclic rats but not in pregnant rats, whereas 2-methoxyestradiol (2ME) and 4-methoxyestradiol mimicked the effect of E(2) on egg transport in cyclic rats but not in pregnant rats. The effect of 2ME on egg transport was blocked by intrabursal administration of the protein kinase inhibitor H-89 or the antiestrogen ICI 182780, but not by actinomycin D or OR486. We conclude that in the absence of mating, COMT-mediated formation of methoxyestradiols in the oviduct is essential for the nongenomic pathway through which E(2) accelerates egg transport in the rat oviduct. Yet unidentified mating-associated signals, which act directly on oviductal cells, shut down the E(2) nongenomic signaling pathway upstream and downstream of methoxyestradiols. These findings highlight a physiological role for methoxyestradiols in the female genital tract, thereby confirming the occurrence of and providing a partial explanation for the mechanism underlying IPS.
Collapse
Affiliation(s)
- Alexis Parada-Bustamante
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331010, Chile
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Peñarroja-Matutano C, Parada-Bustamante A, Orihuela PA, Ríos M, Velásquez LA, Croxatto HB. Genital sensory stimulation shifts estradiol intraoviductal signaling from nongenomic to genomic pathways, independently from prolactin surges. Biol Res 2007; 40:213-222. [PMID: 18064358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Estradiol (E2) accelerates oviductal egg transport through nongenomic pathways involving oviductal protein phosphorylation in non-mated rats, and through genomic pathways in mated rats. Here we investigated the ability of cervico-vaginal stimulation (CVS) to switch the mode of action of E2 in the absence of other male-associated components. Pro-estrous rats were subjected to CVS with a glass rod and 12 hours later were injected subcutaneously with E2 and intrabursally with the RNA synthesis inhibitor Actinomycin D or the protein phosphorylation inhibitor H-89. The number of eggs in the oviduct, assessed 24 h later, showed that Actinomycin D, but not H-89 blocked the E2-induced egg transport acceleration. This clearly indicates that CVS alone, without other mating-associated signals, is able to shift E2 signaling from nongenomic to genomic pathways. Since mating and CVS activate a neuroendocrine reflex that causes iterative prolactin (PRL) surges, the involvement of PRL pathway in this phenomenon was evaluated. Prolactin receptor mRNA and protein expression in the rat oviduct was demonstrated by RT-PCR and Western blot, but their levels were not different on day 2 of the cycle (C2) or pregnancy (P2). Activated ST AT 5a/b (phosphorylated) was detected by Western blot on P2 in the ovary, but not in the oviduct, showing that mating does not stimulate this PRL signalling pathway in the oviduct. Other rats subjected to CVS in the evening of pro-estrus were treated with bromoergocriptine to suppress PRL surges. In these rats, H-89 did not block the E2-induced acceleration of egg transport suggesting that PRL surges are not essential to shift E2 signaling pathways in the oviduct. We conclude that CVS is one of the components of mating that shifts E2 signaling in the oviduct from nongenomic to genomic pathways, and this effect is independent of PRL surges elicited by mating.
Collapse
Affiliation(s)
- C Peñarroja-Matutano
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago-Chile
| | | | | | | | | | | |
Collapse
|
24
|
Ortiz ME, Croxatto HB. Copper-T intrauterine device and levonorgestrel intrauterine system: biological bases of their mechanism of action. Contraception 2007; 75:S16-30. [PMID: 17531610 DOI: 10.1016/j.contraception.2007.01.020] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 01/15/2007] [Indexed: 01/10/2023]
Abstract
All intrauterine devices (IUDs) that have been tested experimentally or clinically induce a local inflammatory reaction of the endometrium whose cellular and humoral components are expressed in the tissue and the fluid filling the uterine cavity. Depending on the reproductive strategy of the species considered and the anatomical features and physiologic mechanisms that characterize their reproductive system, the secondary consequences of this foreign body reaction can be very localized within the uterus, as in the rabbit, or widespread throughout the entire genital tract as in women or even systemic as in some farm animals. Levonorgestrel released from an IUD causes some systemic effects, but local effects such as glandular atrophy and stromal decidualization, in addition to the foreign body reaction, are dominant. Copper ions released from an IUD enhance the inflammatory response and reach concentrations in the luminal fluids of the genital tract that are toxic for spermatozoa. In the human, the entire genital tract appears affected due to luminal transmission of the noxa that accumulates in the uterine lumen. This affects the function and viability of gametes, decreasing the rate of fertilization and lowering the chances of survival of any embryo that may be formed, before it reaches the uterus. The bulk of the data indicate that if any embryos are formed in the chronic presence of an IUD, it happens at a much lower rate than in non-IUD users. The common belief that the usual mechanism of action of IUDs in women is destruction of embryos in the uterus is not supported by empirical evidence.
Collapse
Affiliation(s)
- María Elena Ortiz
- Instituto Chileno de Medicina Reproductiva, Postal code 6500970, Santiago, Chile
| | | |
Collapse
|
25
|
Ríos M, Hermoso M, Sánchez TM, Croxatto HB, Villalón MJ. Effect of oestradiol and progesterone on the instant and directional velocity of microsphere movements in the rat oviduct: gap junctions mediate the kinetic effect of oestradiol. Reprod Fertil Dev 2007; 19:634-40. [PMID: 17601411 DOI: 10.1071/rd06146] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Accepted: 04/16/2007] [Indexed: 11/23/2022] Open
Abstract
The oviducal transport of eggs to the uterus normally takes 72–96 h in the rat, but this is reduced to less than 20 h after a single injection of oestradiol (E2). This accelerated transport is associated with an increased frequency of pendular movements in the isthmic segment of the oviduct, with increased levels of the gap junction (GJ) component Connexin (Cx) 43, and is antagonised by progesterone (P). In the present study, we investigated the effect of these hormones on the instant and directional velocity of pendular movements and the role of the GJ and its Cx43 component in the kinetic response of the oviduct to E2 and P. Using microspheres as egg surrogates, microsphere instant velocity (MIV) was measured following treatment with E2, P or P + E2, which accelerate or delay egg transport. Microspheres were delivered into the oviduct of rats on Day 1 of pregnancy and their movement within the isthmic segment was recorded. Oestrogen increased MIV with faster movement towards the uterus. After P or P + E2, MIV was similar to that in the control group. Two GJ uncouplers, namely 18α- and 18β-glycyrrhetinic acid, blocked the effect of E2 on MIV. Connexin 43 mRNA levels increased over that seen in control with all treatments. In conclusion, the effects of E2 on MIV resulted in faster movements that produced accelerated egg transport towards the uterus. Gap junctions are probably involved as smooth muscle synchronisers in this kinetic effect of E2, but the opposing effects of E2 and P are not exerted at the level of Cx43 transcription.
Collapse
Affiliation(s)
- Mariana Ríos
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | | | | | | | | |
Collapse
|
26
|
Quezada M, Henríquez S, Vargas M, Cardenas H, Tapia A, Rios M, Salvatierra AM, Orihuela PA, Croxatto HB, Velasquez L. Proenkephalin A and the gamma-aminobutyric acid A receptor pi subunit: expression, localization, and dynamic changes in human secretory endometrium. Fertil Steril 2006; 86:1750-7. [PMID: 17074347 DOI: 10.1016/j.fertnstert.2006.05.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 05/06/2006] [Accepted: 05/06/2006] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To compare mRNA and protein levels of proenkephalin A (PEA) and gamma-aminobutyric acid A receptor pi subunit (piGABA-R) in human secretory endometrium before and during receptivity and to determine the cell phenotypes where they are expressed. DESIGN Prospective and observational, comparing prereceptive vs. receptive stages of secretory endometrium within the same nonconceptional menstrual cycle. SETTING University and non-governmental organization (NGO)-based academic and clinical-research facilities. PATIENT(S) Seven healthy, multiparous, surgically sterilized women with spontaneous regular menstrual cycles. INTERVENTION(S) Endometrial biopsies were obtained on LH+3 and LH+7 within the same cycle. MAIN OUTCOME MEASURE(S) Levels of PEA and piGABA-R mRNA were determined by real-time PCR, and protein presence, by immunofluorescence. RESULT(S) The mRNA level of PEA fell, whereas that of piGABA-R increased, during endometrial receptivity. Positive immunostaining of PEA was found in the luminal and glandular epithelium, whereas that of piGABA-R was in luminal epithelium and stromal cells. CONCLUSION(S) The discrete cell-phenotype localization and timing of the changes in the level of PEA and of piGABA-R mRNA and protein suggest an important role for these molecules in switching the human endometrium from a refractory to a receptive state.
Collapse
Affiliation(s)
- Marisol Quezada
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Novikova N, Weisberg E, Stanczyk FZ, Croxatto HB, Fraser IS. Effectiveness of levonorgestrel emergency contraception given before or after ovulation--a pilot study. Contraception 2006; 75:112-8. [PMID: 17241840 DOI: 10.1016/j.contraception.2006.08.015] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 08/28/2006] [Accepted: 08/29/2006] [Indexed: 12/30/2022]
Abstract
BACKGROUND Although widely used, the mechanisms of action of the levonorgestrel emergency contraceptive pill (LNG ECP) are still unclear. There are increasing data to indicate that LNG is particularly effective as an ECP by interrupting follicular development and ovulation. An important outstanding question is whether it has any effect on fertilization or implantation. METHOD Ninety-nine women participated; they were recruited at the time they presented with a request for emergency contraception. All women took LNG 1.5 mg in a single dose during the clinic consultation. A blood sample was taken immediately prior to ingestion of the ECP for estimation of serum LH, estradiol and progesterone levels to calculate the day of ovulation. The specimens were analyzed in a single batch. Based on these endocrine data, we estimated the timing of ovulation to be within a +/-24-h period with an accuracy of around 80%. Women were followed up 4-6 weeks later to ascertain pregnancy status. The effectiveness of ECP when taken before and after ovulation was determined. RESULTS Three women became pregnant despite taking the ECP (pregnancy rate, 3.0%). All three women who became pregnant had unprotected intercourse between Days -1 and 0 and took the ECP on Day +2, based on endocrine data. Day 0 was taken as ovulation day. Among 17 women who had intercourse in the fertile period of the cycle and took the ECP after ovulation occurred (on Days +1 to +2), we could have expected three or four pregnancies; three were observed. Among 34 women who had intercourse on Days -5 to -2 of the fertile period and took ECP before or on the day of ovulation, four pregnancies could have been expected, but none were observed. We found major discrepancies between women's self-report of stage of the cycle and the dating calculation based on endocrine data. CONCLUSION These data are supportive of the concept that the LNG ECP has little or no effect on postovulation events but is highly effective when taken before ovulation.
Collapse
Affiliation(s)
- Natalia Novikova
- Department of Obstetrics and Gynaecology, University of Sydney, NSW, 2006, Australia
| | | | | | | | | |
Collapse
|
28
|
Massai MR, Forcelledo ML, Brache V, Tejada AS, Salvatierra AM, Reyes MV, Alvarez F, Faúndes A, Croxatto HB. Does meloxicam increase the incidence of anovulation induced by single administration of levonorgestrel in emergency contraception? A pilot study. Hum Reprod 2006; 22:434-9. [PMID: 16980507 DOI: 10.1093/humrep/del369] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Levonorgestrel (LNG) consistently prevents follicular rupture only when it is given before the onset of the ovulatory stimulus. As locally synthesized prostaglandin (PG) plays a crucial role in follicular rupture and cyclooxygenase-2 (cox-2) catalyses the final step of PG synthesis, we reasoned that adding a cox-2 inhibitor to LNG would prevent follicular rupture even after the ovulatory process had been triggered by the gonadotrophin surge. METHODS Forty-one women were divided into two groups. One was treated when the size of the leading follicle was 15-17 mm (n=10) and the other when it was >or=18 mm (n=31). Each woman contributed with one cycle treated with LNG 1.5 mg single dose plus placebo and another treated with LNG + meloxicam (Melox) 15 mg, in a randomized order. Serial blood sampling for the assay of LH and follicular monitoring by transvaginal ultrasound were performed before and after treatment. RESULTS Follicular rupture failed to occur within the 5-day period that followed treatment in 50 and 70% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the 15-17 mm group (P=0.15) and in 16 and 39% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the >or=18 mm group (P < 0.052). The overall proportion of cycles with no follicular rupture or ovulatory dysfunction increased significantly by the addition of Melox to LNG (66 versus 88%, P < 0.012; n=41-matched pairs). CONCLUSIONS The trend towards increased incidence of no follicular rupture when Melox was combined with LNG suggests that the addition of a cox-2 inhibitor has the potential to improve the contraceptive efficacy of LNG by a pre-fertilization effect.
Collapse
Affiliation(s)
- M R Massai
- Instituto Chileno de Medicina Reproductiva (ICMER), Santiago, Chile.
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Orihuela PA, Parada-Bustamante A, Zuñiga LM, Croxatto HB. Inositol triphosphate participates in an oestradiol nongenomic signalling pathway involved in accelerated oviductal transport in cycling rats. J Endocrinol 2006; 188:579-88. [PMID: 16522737 DOI: 10.1677/joe.1.06448] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Oestradiol (E(2)) accelerates oviductal transport of oocytes in cycling rats through a nongenomic pathway that involves the cAMP-PKA signalling cascade. Here we examined the role of the inositol triphosphate (IP3) and mitogen-activated protein kinase (MAPK) signalling cascades in this nongenomic pathway. Oestrous rats were injected with E(2) s.c. and intrabursally (i.b) with the selective inhibitors of phospholipase C (PLC) ET-18-OCH(3) or MAPK PD98059. The number of eggs in the oviduct assessed 24 h later showed that ET-18-OCH(3) blocked E(2)-induced egg transport acceleration, whereas PD98059 had no effect. Other oestrous rats were treated with E(2) s.c. and 1, 3 or 6 h later oviducts were excised and the levels of IP3 and phosphorylated MAPK p44/42 (activated) were determined by radioreceptor assay and western blot, respectively. Oestradiol administration increased IP3 level at 1 and 6 h after treatment, whereas activated MAPK p44/42 level was unchanged. Finally, we explored whether cAMP-PKA and PLC-IP3 signalling cascades are coupled. Inhibition of adenylyl cyclase by i.b. injection of SQ 22536 blocked the increase of IP3 levels induced by E(2), while inhibition of PLC by ET-18-OCH(3) had no effect on E(2)-induced PKA activity. Furthermore, activation of adenylyl cyclase by Forskolin increased oviductal IP3 levels. Thus, activation of PLC-IP3 by E(2) requires previous stimulation of cAMP-PKA. We conclude that the nongenomic pathway utilised by E(2) to accelerate oviductal transport of oocytes in cycling rats involves successive activation of the cAMP-PKA and PLC-IP3 signalling cascades and does not require activation of MAPK. These findings clearly illustrate a non-genomic pathway triggered by E(2) that regulates a complex physiologic process accomplished by an entire organ.
Collapse
Affiliation(s)
- Pedro A Orihuela
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile.
| | | | | | | |
Collapse
|
30
|
Abstract
Emergency contraception is the only resource that women can use to avoid becoming pregnant after having sexual intercourse without contraceptive protection. It could be a powerful means to prevent unwanted pregnancies and their devastating consequences for women's health, social wellbeing and life project, and for the unwanted child, if all people had ample access to good quality information, education and services for sexual and reproductive health. In spite of the preventive medicine value of emergency contraception, conservative sectors oppose its availability, appealing to moral values that are not universally shared in pluralistic societies. Excluding the only contraceptive that can be used after intercourse because some consider the mechanism of action to be unacceptable would mean restricting the right of choice of others, and imposing one particular belief or set of values on all members of the community, thus violating the freedom of conscience. Authorities have a moral obligation to protect human rights.
Collapse
|
31
|
Velasquez EV, Trigo RV, Creus S, Campo S, Croxatto HB. Pituitary–ovarian axis during lactational amenorrhoea. I. Longitudinal assessment of follicular growth, gonadotrophins, sex steroids and inhibin levels before and after recovery of menstrual cyclicity. Hum Reprod 2005; 21:909-15. [PMID: 16361292 DOI: 10.1093/humrep/dei410] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Comparisons of follicular development and hormonal profile in the same women during and after lactational amenorrhoea (LA) are scarce. We report follicular growth, pituitary and ovarian hormone serum levels in the same women during LA and in follicular phases after resumption of menstrual cyclicity. METHODS Serum samples were obtained from 10 women during LA between days 60 and 89 post-partum and between days 1 and 4 (early follicular phase; EFP) and 7 and 10 (mid-follicular phase; MFP) of the second and third cycles after LA. RESULTS The number of follicles >3 mm and diameter of the largest follicle were significantly higher during LA when compared to EFP and MFP. Serum levels of inhibin B were similar in LA and EFP and increased significantly in MFP. Pro-alphaC was significantly higher in EFP than in LA and MFP. Estradiol was similar during all stages. In comparison with EFP and MFP, LA is associated with higher prolactin levels, normal or slightly elevated gonadotrophins and increased number and size of follicles without a parallel increase in estradiol, inhibin B and Pro-alphaC. CONCLUSIONS During LA, there is a profound dissociation between follicular growth and follicular endocrine activity, which suggests an alteration in the stimulus-response relationship at the follicular level.
Collapse
Affiliation(s)
- E V Velasquez
- Instituto Chileno de Medicina Reproductiva, José Ramón Gutiérrez 295, Departamento 3, e Instituto Milenio de Biología Fundamental y Aplicada, Santiago, Chile
| | | | | | | | | |
Collapse
|
32
|
Velasquez EV, Creus S, Trigo RV, Cigorraga SB, Pellizzari EH, Croxatto HB, Campo S. Pituitary–ovarian axis during lactational amenorrhoea. II. Longitudinal assessment of serum FSH polymorphism before and after recovery of menstrual cycles. Hum Reprod 2005; 21:916-23. [PMID: 16361291 DOI: 10.1093/humrep/dei411] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The association of normal serum levels of immunoassayable gonadotrophins with anovulation during lactational amenorrhoea (LA) has not been fully explained. METHODS Serum FSH polymorphism was analysed in 10 women during LA between days 60 and 70 post-partum and again, in the mid-follicular phase (MFP), after resuming menstrual cyclicity. FSH microheterogeneity was characterized according to charge, using preparative isoelectric focusing, and according to the inner structure of carbohydrate chains, using lectin chromatography. RESULTS A significantly higher proportion of FSH charge isoforms isolated below pH 4.10 and a lower proportion of FSH isoforms bearing highly branched oligosaccharides were observed during LA when compared to MFP. Further analysis with higher resolution showed that FSH charge isoforms, isolated in the lower pH range in LA, corresponded to FSH molecules bearing highly branched and biantennary oligosaccharides. FSH isoforms bearing hybrid-type oligosaccharides were only present during LA. The circulating FSH isoform mix was significantly less bioactive in LA than in MFP. LA is characterized by a more acidic mix of FSH isoforms, containing hormone bearing less processed oligosaccharides, with decreased biopotency in comparison with the follicular phase. CONCLUSIONS This FSH microheterogeneity may be one of the critical factors contributing to incomplete follicular development and anovulation during LA.
Collapse
Affiliation(s)
- E V Velasquez
- Instituto Chileno de Medicina Reproductiva, José Ramón Gutiérrez 295, Departamento 3, Santiago, Chile
| | | | | | | | | | | | | |
Collapse
|
33
|
Massai R, Quinteros E, Reyes MV, Caviedes R, Zepeda A, Montero JC, Croxatto HB. Extended use of a progesterone-releasing vaginal ring in nursing women: a phase II clinical trial. Contraception 2005; 72:352-7. [PMID: 16246661 DOI: 10.1016/j.contraception.2005.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2005] [Accepted: 05/06/2005] [Indexed: 11/25/2022]
Abstract
AIM This study evaluates the performance of extended use of a progesterone (P)-releasing vaginal ring (PVR) in nursing women. METHOD An open-label, noncomparative study on the safety and contraceptive efficacy of PVR replaced every 4 months of use (instead of 3 months) in 192 PVR acceptors. PVR use was initiated at day 59+/-2 (mean+/-SD) postpartum and continued until weaning or completing the use of three PVRs. RESULTS Plasma P levels attained with the ring decreased from 17+/-1 to 14+/-1 nmol/L (mean+/-SE) from the third to the fourth month of use. These levels are still over the critical level of 10 nmol/L required for contraceptive protection. One pregnancy occurred in the third month of use of the second ring in 1998 woman-months of exposure. Extended use of the ring did not appear to affect breast-feeding performance or the rate of infant growth, and lactational amenorrhea was prolonged. No differences in the characteristics of bleeding between the third and fourth month of ring use were observed. CONCLUSION The results indicate that use of the PVR for 4 months represents a safe and effective contraceptive for nursing women.
Collapse
Affiliation(s)
- Rebeca Massai
- Instituto Chileno de Medicina Reproductiva, Consultorio de Planificación Familiar, J.V. Lastarria 29, Department 101, Santiago, Chile.
| | | | | | | | | | | | | |
Collapse
|
34
|
Croxatto HB. Progesterone receptors and opportunities for contraception. Ernst Schering Res Found Workshop 2005:1-17. [PMID: 15704465 DOI: 10.1007/3-540-27147-3_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Affiliation(s)
- H B Croxatto
- Instituto Chileno de Medicina Reproductive, Jośe Ramon Gutierrez 295, Santiago de Chile.
| |
Collapse
|
35
|
Ortiz RE, Ortiz AC, Gajardo G, Zepeda AJ, Parraguez VH, Ortiz ME, Croxatto HB. Cytologic, hormonal, and ultrasonographic correlates of the menstrual cycle of the New World monkeyCebus apella. Am J Primatol 2005; 66:233-44. [PMID: 16015660 DOI: 10.1002/ajp.20141] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Few reports on the reproductive physiology of Cebus apella have been published. In this study we characterized menstrual cycle events by means of vaginal cytology, ultrasonography (US), and hormonal measurements in serum during three consecutive cycles in 10 females, and assessed the probability that ovulation would occur in the same ovary in consecutive cycles in 18 females. The lengths and phases of the cycles were determined according to vaginal cytology. Taking the first day of endometrial bleeding as the first day of the cycle, the mean cycle length +/- SEM was 19.5+/-0.4 days, with follicular and luteal phases lasting 8.2+/-0.2 and 11.3+/-0.4 days, respectively. The follicular phase included menstruation and the periovulatory period, which was characterized by the presence of a large number of superficial eosinophilic cells in the vaginal smear. The myometrium, endometrium, and ovaries were clearly distinguished on US examination. During each menstrual cycle a single follicle was recruited at random from either ovary. The follicle grew from 3 mm to a maximum diameter of 8-9 mm over the course of 8 days, in association with increasing estradiol (E(2)) serum levels (from 489+/-41 to 1600+/-92 pmol/L). At ovulation, the mean diameter of the dominant follicle usually decreased by >20%, 1 day after the maximum E(2) level was reached. Ovulation was associated with an abrupt fall in E(2), a decreased number of eosinophilic cells, the presence of leukocytes and intermediate cells in the vaginal smear, and a progressive increase in progesterone (P) levels that reached a maximum of 892+/-65 nmol/L on days 3-6 of the luteal phase. The menstrual cycle of Cebus apella differs in several temporal and quantitative aspects from that in humans and Old World primates, but it exhibits the same correlations between ovarian endocrine and morphologic parameters.
Collapse
Affiliation(s)
- R E Ortiz
- Unit of Reproductive Biology and Development, Faculty of Biological Sciences, Catholic University of Chile, Casilla 14-D, Santiago, Chile
| | | | | | | | | | | | | |
Collapse
|
36
|
Croxatto HB, Brache V, Pavez M, Cochon L, Forcelledo ML, Alvarez F, Massai R, Faundes A, Salvatierra AM. Pituitary–ovarian function following the standard levonorgestrel emergency contraceptive dose or a single 0.75-mg dose given on the days preceding ovulation. Contraception 2004; 70:442-50. [PMID: 15541405 DOI: 10.1016/j.contraception.2004.05.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Revised: 03/17/2004] [Accepted: 05/19/2004] [Indexed: 11/24/2022]
Abstract
We assessed to what extent the standard dose of levonorgestrel (LNG), used for emergency contraception, or a single dose (half dose), given in the follicular phase, affects the ovulatory process during the ensuing 5-day period. Fifty-eight women were divided into three groups according to timing of treatment. Each woman contributed with three treatment cycles separated by resting cycles. All received placebo in one cycle, and standard or single dose in two other cycles, in a randomized order. The diameter of the dominant follicle determined the time of treatment. Each woman had the same diameter assigned for all her treatments. Diameters were grouped into 33 categories: 12-14, 15-17 or 18-20 mm. Follicular rupture failed to occur during the 5-day period in 44%, 50% and 36% of cycles with the standard, half dose and placebo, respectively. Ovulatory dysfunction, characterized by follicular rupture associated with absent, blunted or mistimed gonadotropin surge, occurred in 35%, 36% and 5% of standard, single dose or placebo cycles, respectively. In conclusion, LNG can disrupt the ovulatory process in 93% of cycles treated when the diameter of the dominant follicle is between 12 and 17 mm. It is highly probable that this mode of action fully accounts for the contraceptive efficacy as well as the failure rate of this method. The present data suggest that half the dose may be as effective as the standard dose.
Collapse
Affiliation(s)
- H B Croxatto
- Instituto Chileno de Medicina Reproductiva, J. V. Lastarria 29, Department 101, Santiago, Chile.
| | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Cortés PP, Orihuela PA, Zúñiga LM, Velásquez LA, Croxatto HB. Sperm Binding to Oviductal Epithelial Cells in the Rat: Role of Sialic Acid Residues on the Epithelial Surface and Sialic Acid-Binding Sites on the Sperm Surface1. Biol Reprod 2004; 71:1262-9. [PMID: 15201197 DOI: 10.1095/biolreprod.104.027474] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The aim of this study was to assess the participation of carbohydrate residues in the adhesion of spermatozoa to the oviductal epithelium in the rat. We first examined, by lectin labeling, the distribution of glycoconjugates in rat oviducts obtained under various hormonal environments. Several classes of glycoconjugates were abundant in the epithelium, and the expression of some of these molecules varied differentially in ampulla and isthmus, along the estrous cycle and with estradiol and progesterone treatment. Proestrous rats were intraoviductally injected with lectins Dolichos biflorus, Erythrina cristagalli, Helix pomatia, Arachis hypogea, Ulex europaeus I, Triticum vulgaris, or Tritrichomonas mobilensis and were inseminated with 10-20 million epididymal spermatozoa in each uterine horn. Three hours later, the total number of spermatozoa present in the oviduct and the proportion adhering to the epithelium were determined. Intraoviductal administration of lectins did not affect the total number of spermatozoa recovered from the oviduct and only the sialic acid-binding lectin TML decreased the percentage of sperm cells adhering to the epithelium. The involvement of sialic acid in sperm-oviduct adhesion was further explored, inseminating spermatozoa preincubated with mannose, galactose, sialic acid, fucose, fetuin, or asialofetuin. Sialic acid and fetuin inhibited sperm-oviduct binding while other carbohydrates had no effect. Using TML lectin immunohistochemistry, we found that sialic acid-rich glycoconjugates are equally localized in the epithelium of ampulla and isthmus of proestrous rats. The electrophoretic pattern of sialic acid-rich glycoproteins of the epithelium showed 15 major protein bands, for which molecular mass ranged from 200 to 50 kDa with no difference between ampulla and isthmus or between estrous cycle stages. Binding sites for sialic acid-fluorescein isothiocyanate were demonstrated on the surface of rat spermatozoa, and biotinylated sialic acid recognized 11 plasma membrane proteins of sperm cells. These groups of sialic acid-rich glycoproteins in the oviductal epithelium and of sialic acid-binding proteins in the plasma membrane of sperm cells are good candidates for further studies to characterize the molecules responsible for sperm binding. We conclude that there are segment-specific changes of sugar residues present in the oviductal epithelium associated with different endocrine environments. Sperm-oviduct adhesion in the rat occurs by interaction of sialoglycoconjugates present in the epithelial cells with sialic acid-binding proteins on the sperm surface. This replicates the situation previously found in hamsters, disclosing for the first time that species-specificity in the sugar involved in sperm binding is not absolute.
Collapse
Affiliation(s)
- Paula P Cortés
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | | | | | |
Collapse
|
38
|
Massai MR, Pavez M, Fuentealba B, Croxatto HB, d'Arcangues C. Effect of intermittent treatment with mifepristone on bleeding patterns in Norplant® implant users. Contraception 2004; 70:47-54. [PMID: 15208052 DOI: 10.1016/j.contraception.2004.02.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Revised: 01/08/2004] [Accepted: 02/12/2004] [Indexed: 10/26/2022]
Abstract
A double-blind, placebo-controlled, randomized trial, was carried out in 120 Norplant users to evaluate the effect of mifepristone, 100 mg/day administered for 2 consecutive days every 30 days, on the vaginal bleeding pattern. Treatment was given from months 2-7 of implant use. Volunteers recorded bleeding and spotting days, during treatment and for the ensuing 6-month period. During treatment, women on mifepristone recorded the same frequency of bleeding/spotting episodes but significantly less prolonged bleeding episodes than placebo controls (mean +/- SD: 11 +/- 3 vs. 22 +/- 23 days) and their total number of bleeding days was 35% lower than in the placebo group. After the end of mifepristone use, bleeding patterns were similar in both groups. One pregnancy occurred in the mifepristone-treated group, in month 6 of treatment, the outcome was a healthy male baby. We conclude that intermittent administration of mifepristone can offer a clinically significant improvement of the vaginal bleeding pattern in Norplant users.
Collapse
Affiliation(s)
- María Rebeca Massai
- Consultorio de Planificación Familiar, Instituto Chileno de Medicina Reproductiva, José Victorino Lastarria 29, Depto. 101, Santiago, Chile.
| | | | | | | | | |
Collapse
|
39
|
Ortiz ME, Ortiz RE, Fuentes MA, Parraguez VH, Croxatto HB. Post-coital administration of levonorgestrel does not interfere with post-fertilization events in the new-world monkey Cebus apella. Hum Reprod 2004; 19:1352-6. [PMID: 15105392 DOI: 10.1093/humrep/deh180] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Experimental evidence to disprove the belief that emergency contraception with levonorgestrel (LNG) prevents pregnancy by interfering with post-fertilization events is lacking. Here we determined the effect of post-coital and pre-ovulatory administration of LNG on fertility and ovulation, respectively, in the Cebus monkey. METHODS To determine the effect on fertility, LNG 0.75 mg or vehicle were administered orally or s.c. once or twice within the first 24 h after mating occurring very close to the time of ovulation. Females that became pregnant were aborted with mifepristone and re-entered the study after a resting cycle until each of 12 females had contributed, in a randomized order, two LNG and two vehicle-treated cycles. To determine the effect on ovulation, LNG 0.75 mg or vehicle were injected twice coinciding with follicles smaller or larger than 5 mm in diameter. Six females contributed five treated cycles each. RESULTS The pregnancy rate was identical in vehicle- and LNG-treated cycles. LNG inhibited or delayed ovulation only when treatment coincided with a follicle <5 mm diameter. CONCLUSION In Cebus monkeys, LNG can inhibit or delay ovulation but, once fertilization has taken place, it cannot prevent the establishment of pregnancy. These findings do not support the hypothesis that emergency contraception with LNG prevents pregnancy by interfering with post-fertilization events.
Collapse
Affiliation(s)
- M E Ortiz
- Unit of Reproductive Biology and Development, Faculty of Biological Sciences, Catholic University of Chile, Chile.
| | | | | | | | | |
Collapse
|
40
|
Abstract
The concept of luteal phase contraception and the use of mifepristone in clinical trials, which allows for testing of its validity, as well as clinical pharmacological research designed to understand its mode of action, are reviewed. Early luteal phase administration has a variety of morphological, physiological and biochemical effects on the endometrium that are likely to interfere with embryonic-endometrial interactions. In fact, specifically designed pilot clinical trials as well as data derived from emergency contraception studies indicate that early luteal phase administration of mifepristone is highly effective in preventing pregnancy, with minimal disturbance of hormonal parameters or menstrual cyclicity. Mid and late luteal phase administration of mifepristone at doses above 25 mg are highly effective in inducing endometrial bleeding in nonconceptional cycles. However, administration of mifepristone within the period between implantation and expected menses fails to induce bleeding in a significant proportion of cases, and furthermore the bleeding induced does not insure the termination of pregnancy. While the data suggest there is potential for a once-a-month contraceptive pill, it is likely that no molecule endowed with partial agonistic properties, like mifepristone, will completely and reliably suppress the essential functions of progesterone in order to achieve contraceptive efficacy comparable to that of modern contraceptive methods.
Collapse
Affiliation(s)
- Horacio B Croxatto
- Instituto Chileno de Medicina Reproductiva, José Ramón Gutiérrez 295 Apt. #3, Santiago Centro, Chile.
| |
Collapse
|
41
|
Abstract
The use of levonorgestrel (LNG) alone or combined with ethinylestradiol (Yuzpe regimen), for hormonal emergency contraception (HEC) has been approved in several countries whereas in others it is still under debate or has been rejected under the claim that these formulations abort the developmental potential of the embryo. The issue is whether they act by preventing fertilization or by impeding the successful development of the zygote through and beyond implantation. Until now, published work has left this issue largely unresolved, and this paucity of knowledge sustains heated controversies in many settings. A single study indicates that LNG impairs sperm migration in the genital tract of women in ways that could interfere with fertilization. Several studies in women examined the effects of HEC on the outcome of the leading follicle, but lack of precision in the timing of treatment relative to follicular growth, maturation, or rupture confers great variability and inconsistency of results within and between studies. Nonetheless, results indicate that ovulatory dysfunction may account for the prevention of pregnancy in a large proportion of cases. Studies searching for possible alterations of the endometrium at the time implantation would normally take place, found minimal changes of doubtful significance. Recent studies in animals cast serious doubts that LNG prevents pregnancy by interfering with post-fertilization events. Failure to prevent expected pregnancies is close to 25% in women, and this is likely to be accounted for entirely by treatment given too late to prevent fertilization. The exact mode of action of HEC remains undetermined.
Collapse
Affiliation(s)
- Horacio B Croxatto
- Instituto Chileno de Medicina Reproductiva, José Ramón Gutiérrez 295, Dpto. 3, Santiago, Chile.
| | | | | |
Collapse
|
42
|
Abstract
Intra-oviductal administration of RNA obtained from oviducts of estradiol-treated rats resulted in accelerated egg transport (Ríos et al., 1997). It is probable that estradiol-induced messenger RNA (mRNA) entered oviductal cells and was translated into the proteins involved in accelerated egg transport. In order to test this interpretation we deposited in vivo 50 micrograms of pure beta-galactosidase (beta-gal) mRNA, 50 micrograms of pure DNA from the reporter gene beta-gal under SV40 promoter or the vehicle (control oviducts) into the oviductal lumen of rats. Twenty four hours later the beta-gal activity was assayed in oviductal tissue homogenates using o-nitrophenyl-beta-D-galactopyranoside as a substrate. The administration of beta-gal mRNA and pSVBgal plasmid increased beta-gal activity by 71% and 142%, respectively, over the control oviducts. These results indicate that naked DNA and mRNA coding for beta-gal can enter oviductal cells and be translated into an active enzyme. They are consistent with the interpretation that embryo transport acceleration caused by the injection of estradiol-induced RNA in the oviduct involves translation of the injected mRNA.
Collapse
Affiliation(s)
- Mariana Rios
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Casilla114-D, Santiago, Chile
| | | | | |
Collapse
|
43
|
Parada-Bustamante A, Orihuela PA, Croxatto HB. Effect of intrauterine insemination with spermatozoa or foreign protein on the mechanism of action of oestradiol in the rat oviduct. Reproduction 2003; 125:677-82. [PMID: 12713430 DOI: 10.1530/rep.0.1250677] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Previously, we showed that oestradiol accelerates oviductal egg transport through a non-genomic action involving oviductal protein phosphorylation in non-mated rats, and through a genomic action in mated rats. Thus, sensory stimulation, seminal fluid or sperm cells may be the source of signals that switch the mechanism of action of oestradiol in the oviduct to a genomic pathway. The present study examined the ability of spermatozoa to switch the mode of action of oestradiol in the absence of the sensory stimulation and seminal fluid provided by mating. Pro-oestrous rats were inseminated in each uterine horn with epididymal spermatozoa and 12 h later were injected subcutaneously with oestradiol and intrabursally with the mRNA synthesis inhibitor alpha-amanitin. The number of eggs in the oviduct, assessed 24 h later, showed that alpha-amanitin blocked the oestradiol-induced egg transport acceleration, indicating that the interaction of spermatozoa with the genital tract shifts the action of oestradiol from non-genomic to genomic. Other rats were inseminated with live or dead spermatozoa and then treated with the protein kinase inhibitor H-89, and oestradiol. Treatment with H-89 did not block the oestradiol-induced acceleration of egg transport in these rats, although dead spermatozoa did not enter the oviduct, indicating that the mere presence of spermatozoa in the uterus abrogated the non-genomic action of oestradiol in the oviduct. Treatment with H-89 also failed to prevent the acceleration of oviductal egg transport induced by oestradiol in rats inseminated with hamster spermatozoa or with BSA, whereas in rats inseminated with their own serum (autologous proteins), H-89 was able to prevent the effect of oestradiol. This finding reveals that the effect of insemination on the mode of action of oestradiol is neither species-nor sperm-specific and it is produced by foreign organic material. It can be concluded that the presence of spermatozoa or foreign protein in the uterus is one of the components of mating that is capable of switching the action of oestradiol in the oviduct from a non-genomic to a genomic mode.
Collapse
Affiliation(s)
- A Parada-Bustamante
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | |
Collapse
|
44
|
Abstract
Levonorgestrel (LNG), a progestin widely used for regular hormonal contraception, is also used for emergency contraception (EC) to prevent pregnancy after unprotected intercourse. However, its mode of action in EC is only partially understood. One unresolved question is whether or not EC prevents pregnancy by interfering with postfertilization events. Here, we report the effects of acute treatment with LNG upon ovulation, fertilization and implantation in the rat. LNG inhibited ovulation totally or partially, depending on the timing of treatment and/or total dose administered, whereas it had no effect on fertilization or implantation when it was administered shortly before or after mating, or before implantation. It is concluded that acute postcoital administration of LNG at doses several-fold higher than those used for EC in women, which are able to inhibit ovulation, had no postfertilization effect that impairs fertility in the rat.
Collapse
Affiliation(s)
- A L Müller
- Pontifícia Universidad Católica de Chile, Facultad de Ciencias Biológicas, Unidad de Reproducción y Desarrollo, Av. Alameda Bernardo O'Higgins 340, Santiago, Chile
| | | | | |
Collapse
|
45
|
Orihuela PA, Parada-Bustamante A, Cortés PP, Gatica C, Croxatto HB. Estrogen receptor, cyclic adenosine monophosphate, and protein kinase A are involved in the nongenomic pathway by which estradiol accelerates oviductal oocyte transport in cyclic rats. Biol Reprod 2003; 68:1225-31. [PMID: 12606351 DOI: 10.1095/biolreprod.102.011395] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
This investigation examined the role of estrogen receptor (ER) on the stimulatory effect of estradiol (E2) on protein phosphorylation in the oviduct as well as on E2-induced acceleration of oviductal oocyte transport in cyclic rats. Estrous rats were injected with E2 s.c. and with the ER antagonist ICI 182 780 intrabursally (i.b.), and 6 h later, oviducts were excised and protein phosphorylation was determined by Western blot analysis. ICI 182 780 inhibited the E2-induced phosphorylation of some oviductal proteins. Other estrous rats were treated with E2 s.c. and ICI 182 780 i.b. The number of eggs in the oviduct, assessed 24 h later, showed that ICI 182 780 blocked the E2-induced egg transport acceleration. The possible involvement of adenylyl cyclase, protein kinase A (PK-A), protein kinase C (PK-C), or tyrosine kinases on egg transport acceleration induced by E2 was then examined. Selective inhibitors of adenylyl cyclase or PK-A inhibited the E2-induced egg transport acceleration, whereas PK-C or tyrosine kinase inhibitors had no effect. Furthermore, forskolin, an adenylyl cyclase activator, mimicked the effect of E2 on ovum transport and E2 increased the level of cAMP in the oviduct of cycling rats. Finally, we measured PK-A activity in vitro in the presence of E2 or E2-ER complex. Activity of PK-A in the presence of E2 or E2-ER was similar to PK-A alone, showing that E2 or E2-ER did not directly activate PK-A. We conclude that the nongenomic pathway by which E2 accelerates oviductal egg transport in the rat requires absolute participation of ER and cAMP and partial participation of PK-A signaling pathways in the oviduct.
Collapse
Affiliation(s)
- Pedro A Orihuela
- Unidad de Reproducción y Desarrollo, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | | | | | |
Collapse
|
46
|
Maisey K, Nardocci G, Imarai M, Cardenas H, Rios M, Croxatto HB, Heckels JE, Christodoulides M, Velasquez LA. Expression of proinflammatory cytokines and receptors by human fallopian tubes in organ culture following challenge with Neisseria gonorrhoeae. Infect Immun 2003; 71:527-32. [PMID: 12496205 PMCID: PMC143407 DOI: 10.1128/iai.71.1.527-532.2003] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infection of the Fallopian tubes (FT) by Neisseria gonorrhoeae can lead to acute salpingitis, an inflammatory condition, which is a major cause of infertility. Challenge of explants of human FT with gonococci induced mRNA expression and protein secretion for the proinflammatory cytokines interleukin (IL)-1alpha, IL-1beta, and tumor necrosis factor alpha (TNF-alpha) but not for granulocyte-macrophage colony-stimulating factor. In contrast, FT expression of IL-6 and of the cytokine receptors IL-6R, TNF receptor I (TNF-RI), and TNF-RII was constitutive and was not increased by gonococcal challenge. These studies suggest that several proinflammatory cytokines are likely to contribute to the cell and tissue damage observed in gonococcal salpingitis.
Collapse
Affiliation(s)
- Kevin Maisey
- Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH) Instituto Chileno de Medicina Reproductiva, Santiago, Chile.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Gemzell-Danielsson K, van Heusden AM, Killick SR, Croxatto HB, Bouchard P, Cameron S, Bygdeman M. Improving cycle control in progestogen-only contraceptive pill users by intermittent treatment with a new anti-progestogen. Hum Reprod 2002; 17:2588-93. [PMID: 12351534 DOI: 10.1093/humrep/17.10.2588] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The safety and efficacy of the anti-progestogen Org 31710 in improving cycle control in healthy women using the desogestrel progestogen-only pill was investigated in this randomized, double-blind, placebo-controlled study. METHODS A total of 103 women using the 75 micro g desogestrel progestogen-only pill daily also received either 150 mg Org 31710 or placebo once every 28 days, starting on day 1, for a duration of 4-7 treatment cycles. RESULTS The percentage of women with bleeding or spotting (B/S) every day in the placebo group was on average 30% during the whole treatment period and no days without reported B/S occurred. In contrast, a cyclic pattern was observed for the Org 31710 group; a peak incidence of B/S was observed on day 3 or 4 of each cycle, followed by a sharp decrease on cycle days 9-15. Compared with controls, less subjects in the Org 31710 group reported irregular, frequent or prolonged bleeding. These differences were clearly observed in the initial cycles, but were somewhat less pronounced during the later cycles of the treatment period. A relatively high incidence of B/S episodes starting in the second section of the cycle was also observed. CONCLUSION The addition of Org 31710 once a month improved cycle control in women using daily treatment with 75 micro g desogestrel.
Collapse
Affiliation(s)
- K Gemzell-Danielsson
- Department of Woman and Child Health, Division for Obstetrics and Gynaecology, Karolinska Hospital/Institute, Stockholm, Sweden.
| | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
A great deal is now known about the migration of spermatozoa within the female reproductive tract, and how they interact with the oocyte and achieve fertilization in a variety of species. The process involves a series of complex features. It is a mixture of active and passive transport and active migration, with drastic jumps in the numbers of spermatozoa that migrate beyond specific physiological checkpoints, and with interactions occurring between spermatozoa, epithelium and luminal fluid. A reservoir of spermatozoa forms, at a discrete location, to hold and liberate spermatozoa in a gradual fashion. After fertilization has occurred, zygotes are passively transported to the uterus by a series of closely coordinated mechanical events where activities of cilia and smooth muscle predominate. Passage of the embryo from oviduct to uterus is regulated and timed by ovarian hormones, signals associated with mating, and zygotic substances. The diverse and exquisite patterns and regulatory signals typical of sperm migration and ovum transport across many species provide fascinating examples of adaptations according with differing reproductive strategies in various mammals.
Collapse
Affiliation(s)
- Horacio B Croxatto
- Facultad de Ciencias Biologicas, Universidad Catolica de Chile, Santiago, Chile.
| |
Collapse
|
49
|
Croxatto HB, Fuentealba B, Brache V, Salvatierra AM, Alvarez F, Massai R, Cochon L, Faundes A. Effects of the Yuzpe regimen, given during the follicular phase, on ovarian function. Contraception 2002; 65:121-8. [PMID: 11927114 DOI: 10.1016/s0010-7824(01)00299-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study was conducted to assess to what extent the Yuzpe regimen, or half the dose, given in the follicular phase, prevents ovulation during the ensuing 5 days. Sixty women were divided into six groups. All groups received placebo in one cycle and drug in another, in a randomized order. Groups differed by the dose and size of the leading follicle at the time of treatment (12-14, 15-17, or 18-20 mm). Ovulation was absent during the ensuing 5 days in 13 of 20 participants (65%) and in 8 of 20 participants (40%) who received the full and the half dose, respectively, when follicles were 12-17 mm. No ovulation occurred, within the critical period, in 7 of 39 placebo cycles (18%). When follicles were 18-20 mm, treatment did not prevent ovulation. In most drug-treated cycles, plasma gonadotropin and sex steroid levels were significantly depressed within the 5-day period, even when follicular rupture occurred within that period. In conclusion, the Yuzpe regimen can suppress or postpone ovulation to an extent that exceeds the fertile life of spermatozoa. Lack of ovulation within the critical period and dysfunction of the ovulatory process probably account for the contraceptive effect of this method in most cases. The present data do not warrant the use of half the dose of the Yuzpe regimen.
Collapse
Affiliation(s)
- H B Croxatto
- Instituto Chileno de Medicina Reproductiva, J.V. Lastarria 29, Depto. 101, Santiago, Chile.
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Abstract
Four different contraceptive implants for women, in the form of capsules or covered rods, that release either one of the synthetic progestins levonorgestrel, etonogestrel, Nestorone, or Elcometrine and nomegestrol acetate were considered. These progestins act by binding to their receptors located in diverse target cells, which are distributed along the hypothalamic-pituitary-gonadal-genital tract axis. These implants differ in the extent to which each one interferes with various steps of the reproductive process and in the intensity with which each one affects the same process along its effective life, but they have in common the ability to interfere with several key processes required for gamete encounter and fertilization. The steps they interfere with most are the ovulatory process, through partial or complete inhibition of the gonadotropin surge, and by changing the quality of cervical mucus; they restrict or suppress the access of fertile spermatozoa to the site of fertilization. Changes in endometrial development also occur, but this contribution to the contraceptive action is difficult to determine at the present time.
Collapse
|