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1.
Reprod Biomed Online ; 49(2): 103853, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38865783

RESUMEN

RESEARCH QUESTION: How is the production of progesterone (P4) and 17-hydroxy-P4 (17-OH-P4) regulated between theca cells and granulosa cells during the follicular phase, during ovulation and after transformation into a corpus luteum? DESIGN: Three cohorts were examined: (i) 31 women undergoing natural and stimulated cycles, with serum hormone measurements taken every 3 days; (ii) 50 women undergoing ovarian stimulation, with hormone concentrations in serum and follicular fluid assessed at five time points during final follicle maturation; and (iii) 12 women undergoing fertility preservation, with hormone concentrations evaluated via the follicular fluid of small antral follicles. RESULTS: In the early follicular phase, theca cells primarily synthesized 17-OH-P4 while granulosa cells produced limited P4, maintaining the P4:17-OH-P4 ratio <1. As follicles reached follicle selection at a diameter of approximately 10 mm, P4 synthesis in granulosa cells was up-regulated, but P4 was mainly accumulated in follicular fluid. During final maturation, enhanced activity of the enzyme HSD3B2 in granulosa cells enhanced P4 production, with the P4:17-OH-P4 ratio increasing to >1. The concentration of 17-OH-P4 in the luteal phase was similar to that in the follicular phase, but P4 production increased in the luteal phase, yielding a P4:17-OH-P4 ratio significantly >1. CONCLUSIONS: The P4:17-OH-P4 ratio reflects the activity of granulosa cells and theca cells during the follicular phase and following luteinization in the corpus luteum. Managing the function of granulosa cells is key for reducing the concentration of P4 during ovarian stimulation, but the concerted action of FSH and LH on granulosa cells during the second half of the follicular phase makes this complex.

2.
J Assist Reprod Genet ; 38(11): 3039-3045, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34617199

RESUMEN

PURPOSE: This study evaluated the concentrations of hormones resulting from the transplantation of ovarian tissue (OTT) in relation to whether the tissue was frozen at a time close to puberty or above the age of 19 years. METHODS: Six girls and adolescents (aged 9-14 years) who underwent ovarian tissue cryopreservation (OTC) were followed after transplantation in adulthood. After OTT, the women were followed via regular blood samples to evaluate the concentrations of FSH, LH, oestradiol and AMH. Twenty-three women undergoing OTT (aged 19-36 years at the time of OTC) were included as a reference group. All of the women had postmenopausal levels of gonadotropins at the time of transplantation. RESULTS: The return of FSH and LH to normal premenopausal concentrations in adult women transplanted with ovarian tissue that was frozen at a time close to puberty was similar to the profiles in women from the reference group. Serum AMH levels were below the detection limit (via the Roche Elecsys assay) in many samples, but four out of six young girls showed measurable concentrations. Oestradiol similarly increased in the first 12 weeks following transplantation, after which it tended to be higher in women having frozen tissue in adulthood. CONCLUSIONS: Ovarian tissue that was excised from girls at a time close to puberty, after which it was frozen and transplanted in adulthood, interacts with pituitary tissue in a similar manner to ovarian tissue that is frozen from adult women. Follicles located in the ovarian tissue from young girls are equally sensitive to gonadotropin stimulation as follicles from adult women when exposed to postmenopausal levels of gonadotropins. This result indicates that it is not the ovaries that require maturation to sustain full reproductive potential but rather proper FSH and LH stimulation. Moreover, these results support the continued use of OTC in young women.


Asunto(s)
Criopreservación/métodos , Estradiol/sangre , Preservación de la Fertilidad/métodos , Hormona Folículo Estimulante/sangre , Infertilidad Femenina/terapia , Hormona Luteinizante/sangre , Ovario/trasplante , Adolescente , Adulto , Niño , Femenino , Humanos , Pubertad , Adulto Joven
3.
Hum Reprod Open ; 2020(3): hoaa016, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32529047

RESUMEN

BACKGROUND: Infertility is an important side effect of treatments used for cancer and other non-malignant conditions in males. This may be due to the loss of spermatogonial stem cells (SSCs) and/or altered functionality of testicular somatic cells (e.g. Sertoli cells, Leydig cells). Whereas sperm cryopreservation is the first-line procedure to preserve fertility in post-pubertal males, this option does not exist for prepubertal boys. For patients unable to produce sperm and at high risk of losing their fertility, testicular tissue freezing is now proposed as an alternative experimental option to safeguard their fertility. OBJECTIVE AND RATIONALE: With this review, we aim to provide an update on clinical practices and experimental methods, as well as to describe patient management inclusion strategies used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss. SEARCH METHODS: Based on the expertise of the participating centres and a literature search of the progress in clinical practices, patient management strategies and experimental methods used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss were identified. In addition, a survey was conducted amongst European and North American centres/networks that have published papers on their testicular tissue banking activity. OUTCOMES: Since the first publication on murine SSC transplantation in 1994, remarkable progress has been made towards clinical application: cryopreservation protocols for testicular tissue have been developed in animal models and are now offered to patients in clinics as a still experimental procedure. Transplantation methods have been adapted for human testis, and the efficiency and safety of the technique are being evaluated in mouse and primate models. However, important practical, medical and ethical issues must be resolved before fertility restoration can be applied in the clinic.Since the previous survey conducted in 2012, the implementation of testicular tissue cryopreservation as a means to preserve the fertility of prepubertal boys has increased. Data have been collected from 24 co-ordinating centres worldwide, which are actively offering testis tissue cryobanking to safeguard the future fertility of boys. More than 1033 young patients (age range 3 months to 18 years) have already undergone testicular tissue retrieval and storage for fertility preservation. LIMITATIONS REASONS FOR CAUTION: The review does not include the data of all reproductive centres worldwide. Other centres might be offering testicular tissue cryopreservation. Therefore, the numbers might be not representative for the entire field in reproductive medicine and biology worldwide. The key ethical issue regarding fertility preservation in prepubertal boys remains the experimental nature of the intervention. WIDER IMPLICATIONS: The revised procedures can be implemented by the multi-disciplinary teams offering and/or developing treatment strategies to preserve the fertility of prepubertal boys who have a high risk of fertility loss. STUDY FUNDING/COMPETING INTERESTS: The work was funded by ESHRE. None of the authors has a conflict of interest.

4.
Hum Reprod ; 34(5): 942-948, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30927415

RESUMEN

STUDY QUESTION: Is there an association between progesterone (P4) levels on the day of hCG or GnRH trigger and on the day of oocyte retrieval in IVF/ICSI cycles? SUMMARY ANSWER: A significant positive correlation between P4 levels on the day of trigger and the day of oocyte retrieval is seen; HCG trigger induces a steeper P4 increase than GnRHa trigger. WHAT IS KNOWN ALREADY: FSH induces LH receptor (LHR) expression on granulosa cells, and LHR produces progesterone when exposed to LH-like activity. FSH per se also to some extent induces P4 secretion. Late follicular phase progesterone rise has been associated with reduced reproductive outcomes. STUDY DESIGN, SIZE, DURATION: This study is based on data from a previously published RCT conducted from 2009 to 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 384 participants were enrolled; 199 received 5000 IU hCG and 185 received buserelin 0.5 mg for triggering ovulation. P4 was measured on the day of ovulation induction and on the day of oocyte retrieval. FSH consumption and number of retrieved follicles were recorded. MAIN RESULTS AND THE ROLE OF CHANCE: A significant linear relationship between P4 on the day of ovulation induction and oocyte retrieval was seen in the hCG trigger group (P < 0.00001) as well as in the GnRHa trigger group (P < 0.00001). The P4 ratio (the increase in P4 between ovulation induction and oocyte retrieval) was significantly higher in the group of patients with <5 follicles compared to those with 5-15 and >15 follicles (P < 0.0001). The FSH consumption per follicle was significantly higher in the group of patients with <5 follicles compared to those with 5-15 and >15 follicles (P < 0.0001). LIMITATIONS, REASONS FOR CAUTION: Although the study demonstrates a significant correlation between P4 levels before and after ovulation trigger, it does not demonstrate a causal relation to the number of LHRs present on granulosa cells. WIDER IMPLICATIONS OF THE FINDINGS: The findings of this study support the proposed hypothesis that follicles exposed to high levels of FSH during ovarian stimulation will respond with an inappropriately high LHR expression. This in turn causes a high P4 output in response to the trigger. This study further expands our understanding of the underlying mechanisms affecting reproductive outcomes in relation to ovarian stimulation. STUDY FUNDING/COMPETING INTEREST(S): The authors received no specific funding for this work and disclose no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Fármacos para la Fertilidad Femenina/administración & dosificación , Fertilización In Vitro/métodos , Fase Folicular/efectos de los fármacos , Inducción de la Ovulación/métodos , Progesterona/sangre , Adulto , Buserelina/administración & dosificación , Gonadotropina Coriónica/administración & dosificación , Femenino , Fase Folicular/sangre , Hormona Liberadora de Gonadotropina/administración & dosificación , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Humanos , Recuperación del Oocito/métodos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/metabolismo , Embarazo , Índice de Embarazo , Progesterona/metabolismo , Receptores de HL/metabolismo , Resultado del Tratamiento , Adulto Joven
5.
Hum Reprod ; 33(12): 2276-2284, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30358835

RESUMEN

STUDY QUESTION: Can follicle survival in frozen-thawed human ovarian tissue be quantified in situ using the dye Neutral Red (NR) to stain viable follicles specifically? SUMMARY ANSWER: A follicle survival rate within ovarian tissue can be calculated using NR followed by histological evaluation and evidence for a consistently high follicle survival in a series of ovarian tissue from 25 Danish girls and women undergoing ovarian tissue cryopreservation (OTC) was obtained. WHAT IS KNOWN ALREADY: Securing follicle survival in cryopreserved ovarian tissue is crucial for proper quality control when centers wish to implement OTC. The only established technique for validation of follicle survival is xenografting of thawed ovarian tissue to immunodeficient mice. However, this functional test is expensive, time consuming, requires animal facilities and only provides a qualitative-not quantitative-measure for follicle survival. STUDY DESIGN SIZE, DURATION: Quantification of follicle survival in human ovarian tissue donated from 30 girls and women having tissue cryopreserved for fertility preservation from 2000 to 2015 at the Laboratory of Reproductive Biology in Copenhagen, Denmark. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cryopreserved ovarian cortex was donated from 25 girls and young women aged 10-36 years (mean age: 25 years) and the average storage time in liquid nitrogen was 9.1 ± 5.6 years, ranging from 1.6 to 17.9 years. In 12 of the cases, the ovarian tissue was collected from the local hospital and in the other 13 cases the ovarian tissue was transported on ice up to 6 h prior to freezing. Donated fresh ovarian surplus tissue was obtained from five women aged 23-34 years (mean age: 27 years). Ovarian tissues were chopped into small fragments and incubated in culture medium containing 50 mg/ml NR for 3-4 h. Fragments of ovarian tissue containing clearly NR-stained follicles were selected for counting, encapsulated in 4% agar and were processed for histology to calculate a follicular survival rate. MAIN RESULTS AND THE ROLE OF CHANCE: The mean follicle survival rate in the 25 patients after freezing and thawing was 84% ± 11 (mean ±SD), ranging from 50% to 98%. The high follicle survival rate in this clinical series of patients reflects a constant high-quality service performed in our center and confirms the robustness of the slow freezing protocol. No significant association between follicle survival rates and storage time was found using linear regression analysis, suggesting that storage in liquid nitrogen does not affect viability of the tissue. No significant association in follicle survival rates was found between ovarian tissues collected at the local hospital compared to tissues transported on ice prior to freezing, supporting that prolonged cooling does not seem to greatly affect the follicle survival. For the fresh ovarian tissue, the average follicle survival rate was 91% ± 5 (mean ± SD) in five patients, ranging from 81% to 95%. LIMITATIONS, REASONS FOR CAUTION: Even though the NR staining requires active incorporation of the dye, the test is merely a short in situ test that cannot completely replace the functional value of xenografting studies in which the integrity and developmental potential of the ovarian follicles are assessed. WIDER IMPLICATIONS OF THE FINDINGS: OTC is now being employed around the world but to date it has been difficult for centers to evaluate the effectiveness of their program and perform proper quality control. NR staining combined with histological evaluation is the first quantitative method to provide a survival rate for follicles in frozen-thawed human ovarian tissue and offer a valuable and easily applicable tool to validate the cryopreservation procedure when implementing OTC or as routine quality control for the overall freezing performance within tissue banking facilities. STUDY FUNDING/COMPETING INTEREST(S): The Research Pools of Rigshospitalet, the Danish Cancer Foundation, Dagmar Marshalls Foundation, and the Novo Nordic Foundation are thanked for having funded this study. The authors have no conflicts of interest.


Asunto(s)
Supervivencia Celular/fisiología , Preservación de la Fertilidad/métodos , Folículo Ovárico/citología , Adulto , Criopreservación , Femenino , Humanos , Adulto Joven
6.
Hum Reprod ; 33(8): 1506-1516, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29955789

RESUMEN

STUDY QUESTION: Is the chance of a live birth following IVF treatment and fresh embryo transfer affected by early and mid-luteal serum progesterone (P4) levels? SUMMARY ANSWER: Low as well as high serum P4 levels in the early and mid-luteal phase reduce the chance of a live birth following IVF treatment with fresh embryo transfer. WHAT IS KNOWN ALREADY: Data from non-human studies and studies of frozen-thawed embryo transfer cycles indicate that low as well as high P4 levels during the mid-luteal phase decrease the chance of pregnancy. The altered P4 pattern may disrupt the endometrial maturation leading to asynchrony between embryonic development and endometrial receptivity, thereby, compromising implantation and early development of pregnancy. STUDY DESIGN, SIZE, DURATION: Prospective multicenter cohort study of 602 women undergoing IVF treatment. Patients were recruited from four Danish public Fertility Centers from May 2014 to June 2017. The study population was unselected, thus, representing a normal everyday patient cohort. Patients were treated in a long GnRH-agonist protocol or a GnRH-antagonist protocol and triggered for final oocyte maturation with either hCG or a GnRH-agonist. The same vaginal luteal support regimen was applied in all patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Serum P4 levels from the early or mid-luteal phase were correlated to positive hCG and live birth rates (delivery > gestational week 20). Patients were divided into four P4 groups based on raw data of P4 serum levels and reproductive outcomes during early luteal phase (P4<60 nmol/l, P4 60-100 nmol/l, P4 101-400 nmol/l and P4>400 nmol/l) and during mid-luteal phase (P4<150 nmol/l, P4 150-250 nmol/l, P4 251-400 nmol/l and P4>400 nmol/l). MAIN RESULTS AND THE ROLE OF CHANCE: The optimal chance of pregnancy was achieved with serum P4 levels of 60-100 nmol/l in the early luteal phase whereas the optimal P4 level during the mid-luteal phase was 150-250 nmol/l. Below, but most distinctly above these levels, the chance of pregnancy was consistently reduced. With an early luteal P4 level of 60-100 nmol/l, the chance of a positive hCG-test was 73%, 95% CI: [59, 84] following cleavage stage embryo transfer. In contrast, with P4 levels >400 nmol/l, the chance of a positive hCG-test was significantly reduced to 35%, 95% CI: [17, 57], thus, an absolute risk difference of -38%, P = 0.01. A similar negative association between early luteal P4 and live birth rate was found, although it did not reach statistical significance. During the mid-luteal phase, a P4 level of 150-250 nmol/l resulted in an optimal chance of live birth: 54%, 95% CI: [37, 70] compared to 38%, 95% CI: [20, 60] with a P4 level >400 nmol/l, thus, an absolute risk difference of -16%, P = 0.14. All estimates were adjusted for maternal age, maternal BMI, study site, final follicle count and late follicular P4 levels. LIMITATIONS, REASONS FOR CAUTION: This study is the first to explore the possible upper and lower thresholds for luteal P4 following IVF treatment and fresh embryo transfer, and the optimal P4 ranges found in this study should be corroborated in future clinical trials. Furthermore, the P4 thresholds in this study only apply to fresh IVF cycles, using vaginal luteal phase support, as the optimal P4 level in cycles using intramuscular P4 may be different. WIDER IMPLICATIONS OF THE FINDINGS: Future studies are necessary to explore whether additional exogenous luteal P4 supplementation in the low P4 group could increase the chance of a live birth following fresh embryo transfer, and whether patients with luteal P4 levels >400 nmol/l would benefit from segmentation followed by subsequent transfer in frozen/thawed cycles. TRIAL REGISTRATION NUMBER: NCT02129998 (Clinicaltrials.gov). STUDY FUNDING/COMPETING INTEREST(S): L.H.T. received an unrestricted grant from Ferring Pharmaceuticals, Denmark, to support this study. P.H. received unrestricted research grants from MSD, Merck, Gedeon Richter and Ferring Pharmaceuticals outside of this work as well as honoraria for lectures from MSD, Merck and Gedeon Richter outside of this work. U.K. received honoraria for lectures from MSD and Ferring Pharmaceuticals outside of this work. C.A. received unrestricted research grants from MSD, IBSA, and Ferring Pharmaceuticals outside of this work as well as honoraria for lectures from MSD and IBSA. H.O.E. and B.B.P. received an unrestricted research grant from Gedeon Richter outside of this work. K.E., L.B., D.P. and B.H. have no conflict of interest. Furthermore, grants from 'The Health Research Fund of Central Denmark Region', 'The Research Foundation of the Hospital of Central Jutland', 'The Research Foundation of A.P. Møller', 'The Research Foundation of Aase & Ejnar Danielsen', 'The Research Foundation of Dagmar Marshall', 'The Research Foundation of Dir. Jacob Madsen & Hustru Olga Madsen', 'The Research Foundation of Fam. Hede Nielsen' and 'The Danish Medical Research Grant' supported conducting this study. The providers of funding were neither involved in the conduction of the study nor in the writing of the scientific report.


Asunto(s)
Fertilización In Vitro , Infertilidad/terapia , Fase Luteínica/sangre , Progesterona/sangre , Adulto , Biomarcadores/sangre , Dinamarca , Transferencia de Embrión , Femenino , Humanos , Infertilidad/sangre , Infertilidad/diagnóstico , Infertilidad/fisiopatología , Nacimiento Vivo , Embarazo , Índice de Embarazo , Estudios Prospectivos , Inyecciones de Esperma Intracitoplasmáticas , Resultado del Tratamiento
7.
Hum Reprod ; 32(8): 1684-1700, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28854595

RESUMEN

STUDY QUESTION: Do specific transcriptome dynamics in human oocytes from primordial and primary follicles identify novel pathways in oocyte activation? SUMMARY ANSWER: The transcriptomic profiles in oocytes from primordial and primary follicles, respectively, revealed several new canonical pathways as putative mediators of oocyte dormancy and activation. WHAT IS KNOWN ALREADY: Cellular signaling pathways including PI3K/AKT and AKT/mTOR as well as TGF-ß and IGF signaling are known to regulate the primordial-to-primary transition in mammalian follicle development. STUDY DESIGN, SIZE, DURATION: We performed a class comparison study on human oocytes from primordial (n = 436) and primary (n = 182) follicles donated by three women having ovarian tissue cryopreserved before chemotherapy. PARTICIPANTS/MATERIALS, SETTING, METHODS: RNA was extracted from oocytes from primordial and primary follicles isolated by Laser Capture Microdissection, and submitted to the HiSeq Illumina platform. Data mapping, quality control, filtering and expression analysis were performed using Tophat (2.0.4), Cufflinks (2.0.2), BWA (0.6.2) and software R. Modeling of complex biological systems was performed using the IPA® software. Finally, qPCR and immunohistochemistry were employed to explore expression and localization of selected genes and products in human ovarian tissue. MAIN RESULTS AND THE ROLE OF CHANCE: We found 223 and 268 genes down-regulated and up-regulated, respectively, in the oocytes during the human primordial-to-primary follicle transition (P < 0.05 and/or FPKM fold-change >2). IPA® enrichment analysis revealed known pathways ('mTOR Signaling', 'PI3K/AKT Signaling' and 'PTEN Signaling') as well as enriched canonical pathways not previously associated with human ovarian follicle development such as 'ErB Signaling' and 'NGF Signaling' in the down-regulated category and 'Regulation of eIF4 and P70S6K Signaling' and 'HER-2 Signaling in Breast Cancer' in the up-regulated group. Additionally, immunohistochemistry on human ovarian tissue explored the intraovarian localization of VASA, FOXO1 and eIF4E. LARGE SCALE DATA: http://users-birc.au.dk/biopv/published_data/ernst_2017/. LIMITATIONS, REASONS FOR CAUTION: This is a descriptive analysis and no functional studies were performed. The study was based on a limited number of patients and the experimental design could not take into account the natural biological variance in human samples. Therefore, qPCR was used to confirm selected genes alongside immunohistochemical stainings. WIDER IMPLICATIONS OF THE FINDINGS: This study shows, for the first time, a detailed molecular description of global gene transcription activities in oocytes from primordial and primary follicles, respectively. Knowing the global transcription profiles of human oocyte dormancy and activation are important in developing new clinical applications. STUDY FUNDING/COMPETING INTEREST(S): E.H.E. was supported by Health Faculty, Aarhus University and Kong Christian Den Tiendes Fond. K.H. and S.F. were supported by an MRC (UK) project grant MR/M012638/1. K.L.H. was supported by grants from Fonden til Lægevidenskabens Fremme, Kong Christian Den Tiendes Fond. K.L.H. and L.S. were supported by the IDEAS grant from Aarhus University Research Foundation (AUFF). There are no conflicts of interest.


Asunto(s)
Oocitos/metabolismo , Oogénesis/fisiología , Folículo Ovárico/metabolismo , Transducción de Señal/fisiología , Transcriptoma , Femenino , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
9.
Hum Reprod ; 30(12): 2838-45, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26443605

RESUMEN

STUDY QUESTION: What are the results of transplanting cryopreserved ovarian tissue? SUMMARY ANSWER: The transplanted ovarian tissue can last up to 10 years, with no relapses following the 53 transplantations, and the chance of a successful pregnancy is currently around one in three for those with a pregnancy-wish. WHAT IS KNOWN ALREADY: Cryopreservation of ovarian tissue is now gaining ground as a valid method for fertility preservation. More than 36 children worldwide have now been born following this procedure. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study of 41 women who had thawed ovarian tissue transplanted 53 times over a period of 10 years, including 1 patient who was lost to follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS: The 41 Danish women, who had in total 53 transplantations, were followed for ovarian function and fertility outcome. Safety was assessed by monitoring relapse in cancer survivors. MAIN RESULTS, AND THE ROLE OF CHANCE: Among 32 women with a pregnancy-wish, 10 (31%) had a child/children (14 children in total); this included 1 woman with a third trimester on-going pregnancy. In addition, two legal abortions and one second trimester miscarriage occurred. A total of 24 clinical pregnancies were established in the 32 women with a pregnancy-wish. The tissue remained functional for close to 10 years in some cases and lasted only a short period in others. Three relapses occurred but were unlikely to be due to the transplanted tissue. LIMITATIONS, REASONS FOR CAUTION: Self-report through questionnaires with only in-one hospital formalised follow-up of transplanted patients could result in unreported miscarriages. The longevity of the tissue may vary by few months compared with those reported because some patients simply could not remember the date when the tissue became non-functional. WIDER IMPLICATIONS OF THE FINDINGS: Cryopreservation of ovarian tissue is likely to become integrated into the treatment of young women, with cancer, who run a risk of losing their fertility. The full functional lifespan of grafts is still being evaluated, because many of the transplanted women have continued to maintain ovarian activity. Some of our first cases have had tissue functioning for ∼ 10 years.


Asunto(s)
Criopreservación/métodos , Preservación de la Fertilidad/métodos , Fertilidad/fisiología , Ovario/trasplante , Adulto , Dinamarca , Femenino , Humanos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Resultado del Tratamiento
10.
Mol Hum Reprod ; 21(7): 571-82, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25920489

RESUMEN

From early embryonic life, anti-Müllerian hormone (AMH) is produced by Sertoli cells and is essential for male sex differentiation. In females, AMH is produced by immature granulosa cells (GCs) but a definitive function in females is uncertain. We have assessed the cellular localization and specificity of a panel of five novel high-affinity AMH monoclonal antibodies. Two recognize the mature C-terminal form of AMH, whereas three recognize the active pro-mature form of AMH in human tissue. The antibodies were tested on fetal male testicular and mesonephric tissue aged 8-19 weeks post conception (pc), fetal male serum aged 16-26 weeks pc and human immature GCs by immunofluorescence, immunohistochemistry, ELISA and western blotting. The active pro-mature forms of AMH were expressed in both Sertoli cells from human fetal testis and human immature GCs. In contrast, the mature C-terminal form of AMH was hardly detected in Sertoli cells, but was readily detected in GCs. This particular form was also located to the nucleus in GCs, whereas the other investigated AMH forms remained in the cytoplasm. Interestingly, the distribution of the AMH forms in the fetal serum of boys showed that the fraction of inactive precursor AMH only accounted for 4.5% ± 0.6 (mean ± SD) of the total AMH measured, and the remaining AMH was the active pro-mature form. Furthermore, western blot analysis demonstrated a number of previously unrecognized molecular forms of AMH. The present findings suggest that processing of AMH is a tightly regulated process, which is likely to be important for the function of AMH and which differs between the two sexes.


Asunto(s)
Hormona Antimülleriana/metabolismo , Ovario/metabolismo , Proteolisis , Testículo/metabolismo , Adulto , Femenino , Células de la Granulosa/metabolismo , Humanos , Masculino , Células de Sertoli/metabolismo , Testículo/embriología
11.
Mol Cell Endocrinol ; 403: 10-20, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25578602

RESUMEN

The concentration of the important second messenger cAMP is regulated by phosphodiesterases (PDEs) and hence an attractive drug target. However, limited human data are available about the PDEs in the ovary. The aim of the present study was to describe and characterise the PDEs in the human ovary. Results were obtained by analysis of mRNA microarray data from follicles and granulosa cells (GCs), combined RT-PCR and enzymatic activity analysis in GCs, immunohistochemical analysis of ovarian sections and by studying the effect of PDE inhibitors on progesterone production from cultured GCs. We found that PDE3, PDE4, PDE7 and PDE8 are the major families present while PDE11A was not detected. PDE8B was differentially expressed during folliculogenesis. In cultured GCs, inhibition of PDE7 and PDE8 increased basal progesterone secretion while PDE4 inhibition increased forskolin-stimulated progesterone secretion. In conclusion, we identified PDE3, PDE4, PDE7 and PDE8 as the major PDEs in the human ovary.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/genética , Criopreservación , Células de la Granulosa/enzimología , Ovario , ARN Mensajero/genética , 3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , 3',5'-AMP Cíclico Fosfodiesterasas/clasificación , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Adulto , Colforsina/farmacología , Femenino , Expresión Génica , Células de la Granulosa/citología , Células de la Granulosa/efectos de los fármacos , Humanos , Inmunohistoquímica , Isoenzimas/antagonistas & inhibidores , Isoenzimas/clasificación , Isoenzimas/genética , Isoenzimas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Inhibidores de Fosfodiesterasa/farmacología , Cultivo Primario de Células , Progesterona/biosíntesis , Progesterona/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Hum Reprod ; 29(5): 997-1010, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24510971

RESUMEN

STUDY QUESTION: Which genes and molecular mechanisms are involved in the human ovulatory cascade and final oocyte maturation? SUMMARY ANSWER: Up-regulated genes in granulosa cells (GC) represented inflammation, angiogenesis, extracellular matrix, growth factors and genes previously associated with ovarian cancer, while down-regulated genes mainly represented cell cycle and proliferation. WHAT IS KNOWN ALREADY: Radical changes occur in the follicle during final follicle maturation after the ovulatory trigger: these range from ensuring an optimal milieu for the oocyte in meiotic arrest to the release of a mature oocyte and remodeling into a corpus luteum. A wide range of mediators of final follicle maturation has been identified in rodents, non-human primates and cows. STUDY DESIGN, SIZE, DURATION: Prospective cohort study including 24 women undergoing ovarian stimulation with the long gonadotrophin-releasing hormone agonist protocol during 2010-2012 at Holbæk Fertility Clinic. Nine paired samples of GC and 24 paired samples of follicular fluid (FF) were obtained before and after recombinant human chorionic gonadotrophin (rhCG) administration. PARTICIPANTS/MATERIALS, SETTING, METHODS: Nine paired (nine arrays before rhCG and nine arrays after rhCG) samples of GC mRNA were amplified and hybridized to Affymetrix Human Gene 1.0 ST GeneChip arrays, compared and bioinformatically analyzed. Eleven selected genes were validated by quantitative reverse transcriptase PCR. FF hormones were analyzed by enzyme-linked immunosorbent assay. MAIN RESULTS AND THE ROLE OF CHANCE: Eleven hundred and eighty-six genes were differentially expressed (>2-fold, P<0.0001, false discovery rate <0.0012) when comparing GC isolated before and 36 h after hCG, among those were genes known to be expressed at ovulation, i.e. ADAMTS1 and HAS2. Many new ovulation-related genes were revealed, such as CD24, ANKRD22, CLDN11 and FBXO32. FF estrogen, androstenedione and anti-Müllerian hormone decreased significantly while progesterone increased, accompanied by radical changes in the expression of steroidogenic genes (CYP17A, CYP19A, HSD11B1 and HSD11B2, StAR). Genes related to inflammation, angiogenesis, extracellular matrix formation, growth factors and cancer were up-regulated while cell cycle genes were massively down-regulated. Seventy-two genes previously described in connection with ovarian cancer were among the highly regulated genes. In silico analysis for top upstream regulators of the ovulatory trigger suggested--besides LH--TNF, IGF1, PGR, AR, EGR1 (early growth response 1), ERK1/2 (extracellular signal regulated kinase 1/2) and CDKN1A (cyclin-dependent kinase inhibitor 1A) as potential mediators of the LH/hCG response. LIMITATIONS, REASONS FOR CAUTION: The present dataset was generated from women under hormonal stimulation. However, comparison with a macaque natural cycle whole follicle ovulation dataset revealed major overlap, supporting the idea that the ovulation-related genes found in this study are relevant in the human natural cycle. WIDER IMPLICATIONS OF THE FINDINGS: These data will serve as a research resource for genes involved in human ovulation and final oocyte maturation. Ovulation-related genes might be good candidate biomarkers of follicle and oocyte health. Further, some of the ovulation-related genes may serve as future ovarian cancer biomarkers. STUDY FUNDING/COMPETING INTEREST(S): Grants from the Research Fund of Region Sjælland are gratefully acknowledged. None of the authors declared any conflict of interest. TRIAL REGISTRATION NUMBER: Not applicable.


Asunto(s)
Células de la Granulosa/metabolismo , Inducción de la Ovulación , Ovulación/genética , Transcriptoma , Adulto , Gonadotropina Coriónica/farmacología , Femenino , Células de la Granulosa/efectos de los fármacos , Humanos , Ovulación/efectos de los fármacos , Ovulación/metabolismo , Estudios Prospectivos
13.
Hum Reprod ; 28(9): 2511-21, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23753114

RESUMEN

STUDY QUESTION: Does a GnRH agonist (GnRHa) trigger followed by a bolus of 1.500 IU hCG in a group of patients at risk of ovarian hyperstimulation syndrome (OHSS) reduce the OHSS incidence compared with hCG trigger? SUMMARY ANSWER: A GnRHa trigger followed by early luteal hCG support with one bolus of 1.500 IU hCG appears to reduce OHSS in patients at risk of OHSS; however, in a low-risk group a second bolus of 1.500 IU hCG induced two cases of late onset OHSS. WHAT IS KNOWN ALREADY: A GnRHa trigger is an alternative to hCG in GnRH antagonist co-treated cycles. STUDY DESIGN, SIZE, DURATION: Two RCTs were performed in four Danish IVF units. A total of 446 patients were assessed for eligibility and 390 patients were enrolled in the study from January 2009 until December 2011. The primary outcome of the study was OHSS incidence in the group at risk of OHSS. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients received a fixed dose of recombinant human FSH for the first 4 days. On the day of triggering, patients were assessed for their risk of OHSS based on the total number of follicles ≥11 mm diameter, and were classified as being at risk of OHSS when the total number of follicles ≥11 mm was between 15 and 25 and at low risk of OHSS when the total number of follicles ≥11 mm was ≤14. Two separate randomization lists were used for each of the OHSS risk groups. Women at risk of OHSS were allocated (RCT 1) to either: Group A (n = 60), ovulation triggering with a bolus of 0.5 mg buserelin (GnRHa) s.c. followed by a single bolus of 1.500 IU hCG s.c. after the oocyte retrieval-or: Group B (n = 58): 5.000 IU hCG. Similarly, women at low risk of OHSS were allocated (RCT 2) to receive either: Group C (n = 125), a bolus of 0.5 mg buserelin s.c., followed by a bolus of 1.500 IU hCG s.c. after oocyte retrieval and a second bolus of 1.500 IU hCG on the day of oocyte retrieval +5-or: Group D (n = 141), 5.000 IU hCG. Groups C and D were included in order to obtain preliminary data. MAIN RESULTS AND THE ROLE OF CHANCE: In women at risk of OHSS (RCT 1) (15-25 follicles) no OHSS case was seen in Group A (GnRHa trigger and one bolus of 1.500 IU hCG), whereas two cases of moderate late-onset OHSS occurred in group B (3.4%), (P = 0.24). In contrast, in women at a low risk of OHSS (RCT 2) (≤14 follicles) two cases of late-onset OHSS occurred in Group C (GnRHa trigger and two boluses of 1.500 IU hCG), whereas no OHSS case was encountered in Group D (P = 0.22). LIMITATIONS, REASONS FOR CAUTION: Although the first RCT was powered to include 168 patients at risk of OHSS (15-25 follicles ≥11 mm) randomized to either GnRHa trigger or hCG trigger, the trial was prematurely discontinued when a total of 118 patients at risk of OHSS were randomized. In addition the second RCT in the OHSS low-risk group was designed as a feasibility study to assess the incidence of OHSS after GnRHa trigger and dual hCG administration versus 5.000 IU hCG. No power calculation was performed for this trial. In addition, there was a lack of blinding in the RCTs. WIDER IMPLICATIONS OF THE FINDINGS: Although a non-significant result, one bolus of 1.500 IU hCG after GnRHa trigger tended to reduce the OHSS rate in patients with 15-25 follicles ≥11 mm as well as secure the ongoing pregnancy rate. In contrast, in patients at low risk of OHSS the administration of two boluses of 1.500 IU hCG after GnRHa trigger should be avoided as it may induce OHSS.


Asunto(s)
Gonadotropina Coriónica/administración & dosificación , Cuerpo Lúteo/efectos de los fármacos , Fármacos para la Fertilidad Femenina/farmacología , Hormona Liberadora de Gonadotropina/agonistas , Síndrome de Hiperestimulación Ovárica/prevención & control , Inducción de la Ovulación/efectos adversos , Medicina de Precisión , Adulto , Gonadotropina Coriónica/efectos adversos , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/diagnóstico por imagen , Dinamarca/epidemiología , Relación Dosis-Respuesta a Droga , Terminación Anticipada de los Ensayos Clínicos , Estudios de Factibilidad , Femenino , Fármacos para la Fertilidad Femenina/efectos adversos , Fertilización In Vitro/efectos adversos , Hormona Folículo Estimulante Humana/farmacología , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Incidencia , Infertilidad Femenina/diagnóstico por imagen , Infertilidad Femenina/terapia , Síndrome de Hiperestimulación Ovárica/epidemiología , Ovario/diagnóstico por imagen , Ovario/efectos de los fármacos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/farmacología , Riesgo , Índice de Severidad de la Enfermedad , Ultrasonografía
14.
Reprod Domest Anim ; 47 Suppl 6: 300-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23279524

RESUMEN

Assisted reproductive technology (ART) is considered an important tool in the conservation of endangered species, but often the most limiting factor of ART is the availability of mature oocytes. The aim of the present study was to investigate the feasibility of preserving female germ cells from ovaries of female lions (Panthera leo). Good quality cumulus-oocyte complexes (COCs) were isolated and subjected to in vitro maturation (IVM). In addition, ovarian cortex was obtained and cut into pieces for culture and cryopreservation by slow freezing. The survival of ovarian follicles was assessed by histology. Frozen-thawed samples of ovarian cortex samples were xenotransplanted under the skin of ovariectomized immunodeficient mouse for 28 days. Overall, 178 intact COCs were obtained from 13 lions, but only 28.1% were matured in vitro indicating insufficient IVM conditions. In contrast, almost all follicles within the ovarian cortex survived culture when the original sample was from a young healthy lion collected immediately after euthanasia. Within the xenotransplants, the number of primordial follicles decreased after 28 days by 20%, but the relation between primordial and growing follicles changed in favour of follicular growth. Female gamete rescue from valuable felids may be performed by slow freeze cryopreservation of ovarian cortex. Although the IVM protocol for lions is not yet optimized, mature oocytes may be obtained after long-term xenotransplantation and IVM and could potentially represent one way of salvage of endangered felid species in the future.


Asunto(s)
Criopreservación/veterinaria , Leones/fisiología , Folículo Ovárico/fisiología , Animales , Criopreservación/métodos , Femenino , Ratones , Ratones Desnudos , Trasplante Heterólogo
15.
BJOG ; 117(2): 163-74, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19874293

RESUMEN

Girls and young women suffering from a malignant disease that requires treatment with chemo- and/or radiotherapy are at risk of losing fertility. The most significant risk factors are age and type of treatment given. Preserving fertility is of high priority to both the young patient and her parents. This article reviews the effect of chemo- and radiotherapy on gonadal function, and thus fertility, and offers different fertility preserving methods based on the literature. Cryopreservation of ovarian tissue is a possible way of preserving fertility in this group of patients in the future.


Asunto(s)
Criopreservación , Infertilidad Femenina/terapia , Preservación de Órganos/métodos , Insuficiencia Ovárica Primaria/etiología , Adolescente , Adulto , Factores de Edad , Antineoplásicos Alquilantes/efectos adversos , Niño , Dinamarca , Femenino , Fertilidad/efectos de los fármacos , Fertilidad/efectos de la radiación , Fertilización In Vitro , Humanos , Lactante , Infertilidad Femenina/etiología , Infertilidad Femenina/prevención & control , Masculino , Menarquia/efectos de los fármacos , Menarquia/efectos de la radiación , Neoplasias/terapia , Recuperación del Oocito/métodos , Oocitos/crecimiento & desarrollo , Oocitos/trasplante , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/efectos de la radiación , Embarazo , Insuficiencia Ovárica Primaria/terapia , Pubertad/efectos de los fármacos , Pubertad/efectos de la radiación , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/prevención & control , Sobrevivientes/estadística & datos numéricos , Adulto Joven
16.
Int J Androl ; 31(6): 565-72, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17877720

RESUMEN

Smoking during pregnancy has been reported to alter levels of reproductive hormones in adult sons. From a Danish pregnancy cohort established in 1984-1987, 347 out of 5109 sons were selected according to their exposure to tobacco smoke in foetal life. From February 2005 to January 2006, a blood sample from each young man (18-21 years) was collected and analysed for reproductive hormones. There were no apparent trends of increasing or decreasing hormonal levels with increased exposure to maternal tobacco smoking during pregnancy. Only the free testosterone/free estradiol ratios increased with increased maternal smoking during pregnancy (p for trend = 0.05). No trends for increasing odds ratios for high follicle-stimulating hormone (> or =25 percentile) or low inhibin B (< or =25 percentile) in relation to maternal smoking were observed. We found no major indication of long-term effects of pre-natal exposure to tobacco smoke on the levels of reproductive hormones later in life, but the data may suggest a shift in the hypothalamo-pituitary-gonadal axis towards higher androgenicity. This result was, however, of only borderline significance and could be because of chance.


Asunto(s)
Hijos Adultos , Estradiol/sangre , Hormona Folículo Estimulante/sangre , Inhibinas/sangre , Complicaciones del Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Fumar , Testosterona/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Embarazo , Fumar/efectos adversos , Contaminación por Humo de Tabaco , Adulto Joven
17.
Hum Reprod ; 16(12): 2501-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11726566

RESUMEN

BACKGROUND: The aim of this study was to evaluate whether characteristics of human ovulation correlate with age and pregnancy potential. METHODS: Two groups of women with regular menstrual cycles were included (i.e. one fertile and one infertile group), which were divided into four age groups (< or =29, 30-34, 35-39, > or = 40 years). Monitoring included observations of follicular phase length, whether ovulations occurred from the left or right ovary, the pattern of ovulations in succeeding natural cycles and, in a subset of women, early follicular phase FSH concentrations. RESULTS: Ovulation moving from one ovary to the other in two consecutive cycles (i.e. contralateral ovulation) was inversely correlated with age, showing a ratio of contralateral ovulation per contra plus ipsilateral ovulations (C/C+I) of 62% in women <29 years, gradually decreasing to 42% in women >40 years. The ratio of right-sided ovulation per right plus left-sided ovulations (R/R+L) was unrelated to age and remained almost constant at a level of approximately 55%. The follicular phase length was inversely correlated with age, being 16.2 +/- 2.9, 15.4 +/- 2.9, 14.8 +/- 2.8 and 13.7 +/- 1.3 days in women < 29, 30-34, 35-39 and >40 years of age respectively. The follicular phase length was similar when comparing ovulations occurring from the right and left ovary, but comparing two successive cycles, the length of the follicular phase of the second cycle, showing contralateral ovulation, was shorter than ipsilateral ovulation with two consecutive ovulations in the same ovary. The pregnancy rate of the four groups decreased with age, being 14, 12, 5 and 3% respectively. The C/C+I ratio correlates with pregnancy rate and follicular phase length, and inversely correlates with basal FSH, whereas R/R+L is unrelated to age and pregnancy rate. CONCLUSIONS: Human ovulation shows characteristics related to age. The interaction between the two ovaries seems to be most pronounced in the younger years, where ovulations jump from one ovary to the other more frequently than later on in life. The C/C+I ratio shows a clear correlation with age and pregnancy rate.


Asunto(s)
Infertilidad Femenina/fisiopatología , Ciclo Menstrual , Ovulación , Adulto , Envejecimiento , Femenino , Hormona Folículo Estimulante/sangre , Fase Folicular , Humanos , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos
18.
Ugeskr Laeger ; 163(37): 5007-13, 2001 Sep 10.
Artículo en Danés | MEDLINE | ID: mdl-11573373

RESUMEN

The medical treatment of various cancers may, as long-term sequelae, cause infertility in girls and young women. In order to preserve the fertility of such women, techniques to cryopreserve ovarian tissue have gained considerable interest during recent years. The ovarian tissue is cryopreserved before cancer treatment is commenced, and first replaced when the woman has been cured. Based on the successful results from the use of this technique in test animals, where normal live young have been born, cryopreservation of human ovarian tissue has been initiated in a number of fertility clinics worldwide over the last few years. So far, only two women have experienced transplantation of cryopreserved ovarian tissue. Menstrual cycles and oestradiol production were restored in both women, but restoration of fertility have not yet been demonstrated. This review describes the technique and its present possibilities and limitations. The legal aspects in Denmark are presented and some ethical aspects described.


Asunto(s)
Criopreservación , Infertilidad Femenina/prevención & control , Ovario , Óvulo , Reimplantación , Conservación de Tejido , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Criopreservación/métodos , Criopreservación/tendencias , Dinamarca , Ética Médica , Femenino , Humanos , Infertilidad Femenina/inducido químicamente , Infertilidad Femenina/etiología , Legislación Médica , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Ovario/citología , Ovario/trasplante , Óvulo/trasplante , Radioterapia/efectos adversos , Reimplantación/métodos , Reimplantación/tendencias , Conservación de Tejido/métodos , Conservación de Tejido/tendencias
19.
Mol Hum Reprod ; 7(2): 129-35, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11160838

RESUMEN

The ability of different isoforms of follicle stimulating hormone (FSH) to induce accumulation of cAMP in cultured mouse cumulus-oocyte-complexes (COC) was evaluated in a time course study. Using isoform fractions representing less acidic (pI 6.43-5.69), mid-acidic (pI 5.62-4.96) and acidic (pI 4.69-3.75) isoforms, the accumulation of cAMP was monitored after an exposure time of 0, 5, 10, 15, 30, 60, 120 and 180 min. In addition, cAMP production was monitored for 0, 5, 10, 15 and 30 min following a 5 min exposure to FSH isoform fractions. Based on FSH measurements using radioimmunoassays, the less and mid-acidic isoforms caused almost twice as much cAMP to be accumulated than the acidic isoform fraction, thereby confirming an enhanced biological activity of FSH isoforms with a isoelectric point (pI) of >5.0. For all isoform fractions, maximal accumulation of cAMP was achieved after 30 min of exposure, after which the production declined to background levels. After a 5 min exposure to isoform fractions, levels of cAMP were significantly higher in the less acidic isoform fractions, but after isoform removal, the decline in cAMP production to background levels followed a similar time course. The results demonstrate that FSH isoforms with a pI of >5.0 induced significant biological responses within a period of 30 min and that prolonged exposure caused attenuated signal transduction. The present results, set in the context of the pulsatile characteristics of FSH release from the pituitary and the reported half-life of less acidic isoforms of approximately 35 min, make it conceivable that isoforms with a pI >5.0 actually possess important physiological functions during the periovulatory period.


Asunto(s)
AMP Cíclico/biosíntesis , Hormona Folículo Estimulante/farmacología , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Animales , Femenino , Hormona Folículo Estimulante/química , Hormona Folículo Estimulante/fisiología , Fase Folicular/fisiología , Técnicas In Vitro , Punto Isoeléctrico , Cinética , Ratones , Ratones Endogámicos C57BL , Ovario/citología , Ovario/efectos de los fármacos , Ovario/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/farmacología , Isoformas de Proteínas/fisiología
20.
Zygote ; 9(4): 283-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11771893

RESUMEN

The proteinase inhibitor inter-alpha trypsin inhibitor (ITI) is a blood-derived protein necessary for normal female fertility. Absence of ITI leads to ovulation of naked oocytes that cannot fertilise. ITI consists of two heavy chains (ITI-HC) and bikunin linked by a chrondroitin sulphate. By binding to hyaluronate, ITI-HC stabilises the extracellular matrix, but ITI-HC also binds to proteoglycans in follicular fluid. In vivo concentrations of ITI components in preovulatory follicular fluid, free as well as bound to hyaluronate or proteoglycan, are unknown. In order to quantify these components, 58 follicular fluids and 13 blood samples were collected in connection with in vitro fertilisation and embryo transfer treatment of 13 women. Quantitation of glycosaminoglycan-bound ITI-HC was performed after separation from free ITI in agarose gel. ITI components were determined by immunoelectrophoresis and hyaluronate by an ELISA method. The follicular fluid concentration of ITI was on average 70% of that in plasma and the concentration of hyaluronate remained low despite follicular production, suggesting that the production of hyaluronate is the rate-limiting step in the formation of the extracellular matrix of the oocyte-cumulus complex. In follicular fluid, the concentration of free ITI-HC was higher than that of glycosaminoglycan-bound ITI-HC. Addition of exogeneous hyaluronate doubled the amount of hyaluronate-bound ITI-HC, further supporting the notion that ITI in follicular fluid is not rate-limiting for cumulus expansion in vivo.


Asunto(s)
alfa-Globulinas/fisiología , Líquido Folicular/fisiología , Glicosaminoglicanos/fisiología , Inhibidor de la Tripsina de Soja de Kunitz , Adulto , Femenino , Humanos , Ácido Hialurónico/fisiología , Glicoproteínas de Membrana/fisiología , Folículo Ovárico/crecimiento & desarrollo
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