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Uju CN, Unniappan S. Growth factors and female reproduction in vertebrates. Mol Cell Endocrinol 2024; 579:112091. [PMID: 37863469 DOI: 10.1016/j.mce.2023.112091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/05/2023] [Accepted: 10/13/2023] [Indexed: 10/22/2023]
Abstract
Female reproductive efficiency is influenced by the outcomes of various processes, including folliculogenesis, apoptosis, response to gonadotropin signaling, oocyte maturation, and ovulation. The role of hormones in regulating these processes and other reproductive activities has been well established. It is becoming increasingly evident that in addition to well-characterized hormones, growth factors play vital roles in regulating some of these reproductive activities. Growth factors and their receptors are widely distributed in vertebrate ovaries at different stages of ovarian development, indicating their involvement in intraovarian reproductive functions. In the ovary, cell surface receptors allow growth factors to regulate intraovarian reproductive activities. Understanding these actions in the reproductive axis would provide a tool to target growth factors and/or their receptors to yield desirable reproductive outcomes. These include enrichment of in vitro maturation and fertilization culture media, and management of infertility. This review discusses some widely characterized growth factors belonging to the TGF, EGF, IGF, FGF, and BDNF family of peptides and their role in female reproduction in vertebrates, with a focus on mammals.
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Affiliation(s)
- Chinelo N Uju
- Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - Suraj Unniappan
- Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B4, Canada.
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2
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Izadi M, Rezvani ME, Aliabadi A, Karimi M, Aflatoonian B. Mesenchymal stem cells-derived exosomes as a promising new approach for the treatment of infertility caused by polycystic ovary syndrome. Front Pharmacol 2022; 13:1021581. [PMID: 36299896 PMCID: PMC9589245 DOI: 10.3389/fphar.2022.1021581] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/28/2022] [Indexed: 11/13/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is a multifactorial metabolic and most common endocrine disorder that its prevalence, depending on different methods of evaluating PCOS traits, varies from 4% to 21%. Chronic low-grade inflammation and irregular apoptosis of granulosa cells play a crucial role in the pathogenesis of PCOS infertility. Mesenchymal stem cells (MSCs)-derived exosomes and extracellular vesicles (EVs) are lipid bilayer complexes that act as a means of intercellular transferring of proteins, lipids, DNA and different types of RNAs. It seems that this nanoparticles have therapeutic effects on the PCOS ovary such as regulating immunity response, anti-inflammatory (local and systemic) and suppress of granulosa cells (GCs) apoptosis. Although there are few studies demonstrating the effects of exosomes on PCOS and their exact mechanisms is still unknown, in the present study we reviewed the available studies of the functions of MSC-derived exosome, EVs and secretome on apoptosis of granulosa cells and inflammation in the ovary. Therefore, the novel cell-free therapeutic approaches for PCOS were suggested in this study.
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Affiliation(s)
- Mahin Izadi
- Research and Clinical Center for Infertility, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- Department of Reproductive Biology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mohammad Ebrahim Rezvani
- Department of Physiology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Ali Aliabadi
- Department of Physiology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mahdieh Karimi
- Stem Cell Biology Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Behrouz Aflatoonian
- Research and Clinical Center for Infertility, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- Department of Reproductive Biology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- Stem Cell Biology Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- *Correspondence: Behrouz Aflatoonian,
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Effects of embryonic stem cell-conditioned medium on the preimplantation development of mouse embryos. ZYGOTE 2022; 30:464-470. [PMID: 35172909 DOI: 10.1017/s0967199421000575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The production of high-quality embryos in the laboratory and a successful pregnancy are closely related to the condition and contents of oocyte and embryo culture media. In this study, we investigated the effects of embryonic stem cell-conditioned medium (ESCCM) and embryonic stem cells growth medium (ESCGM) compared with potassium-enriched simplex optimized medium (KSOM) on preimplantation embryo development stages during natural or in vitro fertilization (IVF). Birth rate of pups was measured. To obtain mature oocytes, and 2-cell and 8-cell embryos, human chorionic gonadotropin (HCG) was injected 48 h after i.p. injection of 5 units of pregnant mare serum gonadotropin. Mature oocytes were obtained from non-mated female mice 14 h after HCG injection. To obtain 2-cell and 8-cell embryos, mated female mice, 1 day and 3 days, respectively, after HCG injection, were used. Mature oocytes were fertilized in HTF medium. Embryos obtained from natural or in vitro fertilization were cultured in experimental media, ESCCM and ESCGM, or KSOM as the control culture medium. Embryos that developed to the blastocyst stage were transferred to the uteri of pseudopregnant mice and effects of the experimental media on embryo viability were determined. ESCCM and ESCGM could not pass the embryo after the 2-cell stage, but they were suitable for the development of the embryo from the 8-cell stage to the blastocyst. It can be concluded that the embryo has various requirements at different stages of development.
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He M, Zhang T, Yang Y, Wang C. Mechanisms of Oocyte Maturation and Related Epigenetic Regulation. Front Cell Dev Biol 2021; 9:654028. [PMID: 33842483 PMCID: PMC8025927 DOI: 10.3389/fcell.2021.654028] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 02/25/2021] [Indexed: 12/16/2022] Open
Abstract
Meiosis is the basis of sexual reproduction. In female mammals, meiosis of oocytes starts before birth and sustains at the dictyate stage of meiotic prophase I before gonadotropins-induced ovulation happens. Once meiosis gets started, the oocytes undergo the leptotene, zygotene, and pachytene stages, and then arrest at the dictyate stage. During each estrus cycle in mammals, or menstrual cycle in humans, a small portion of oocytes within preovulatory follicles may resume meiosis. It is crucial for females to supply high quality mature oocytes for sustaining fertility, which is generally achieved by fine-tuning oocyte meiotic arrest and resumption progression. Anything that disturbs the process may result in failure of oogenesis and seriously affect both the fertility and the health of females. Therefore, uncovering the regulatory network of oocyte meiosis progression illuminates not only how the foundations of mammalian reproduction are laid, but how mis-regulation of these steps result in infertility. In order to provide an overview of the recently uncovered cellular and molecular mechanism during oocyte maturation, especially epigenetic modification, the progress of the regulatory network of oocyte meiosis progression including meiosis arrest and meiosis resumption induced by gonadotropins is summarized. Then, advances in the epigenetic aspects, such as histone acetylation, phosphorylation, methylation, glycosylation, ubiquitination, and SUMOylation related to the quality of oocyte maturation are reviewed.
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Affiliation(s)
- Meina He
- Department of Biology, School of Basic Medical Science, Guizhou Medical University, Guiyang, China
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, Yinchuan, China
| | - Tuo Zhang
- Department of Physiology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, Yinchuan, China
| | - Yi Yang
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, Yinchuan, China
| | - Chao Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, Yinchuan, China
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Effects of Human Endothelial Progenitor Cell and Its Conditioned Medium on Oocyte Development and Subsequent Embryo Development. Int J Mol Sci 2020; 21:ijms21217983. [PMID: 33121114 PMCID: PMC7662943 DOI: 10.3390/ijms21217983] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/20/2020] [Accepted: 10/23/2020] [Indexed: 12/15/2022] Open
Abstract
Human endothelial progenitor cells (EPCs) secrete numerous growth factors, and they have been applied to regenerative medicine for their roles in angiogenesis as well as neovascularization. Angiogenesis is one of the essential factors for the maturation of ovarian follicles; however, the physiological function of EPCs or their derivatives on in vitro culture systems has not been fully understood. The aim of this study was to evaluate the effectiveness of EPCs and their conditioned medium (EPC-CM) on oocyte development and subsequent embryo development. In the results, the oocyte development and subsequent embryo development were significantly improved in EPCs and the EPC-CM group. In addition, markedly increased levels of growth factors/cytokines, such as basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), insulin growth factor-1 (IGF-1), interleukin-10 (IL-10), and epidermal growth factor (EGF), were observed in medium from the EPC-CM group. Additionally, EPC-CM after in vitro maturation (IVM) had significantly decreased reactive oxygen species (ROS) levels compared to those of other groups. Transcriptional levels of growth factor receptor-related genes (FGFR2, IGF1R) and anti-apoptotic-related gene (BCL2) were significantly upregulated in cumulus cells/oocytes from the EPC-CM group compared with those from the control. Furthermore, the expression levels of cumulus expansion-related genes (PTGS2, TNFAIP6, HAS2) and oocyte-maturation-related factors (GDF9, BMP15) were significantly enhanced in the EPC-CM group. Consequently, the present study provides the first evidence that EPC-CM contains several essential growth factors for oocyte development by regulating genes involved in oocyte maturation.
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Hatırnaz Ş, Ata B, Hatırnaz ES, Dahan MH, Tannus S, Tan J, Tan SL. Oocyte in vitro maturation: A sytematic review. Turk J Obstet Gynecol 2018; 15:112-125. [PMID: 29971189 PMCID: PMC6022428 DOI: 10.4274/tjod.23911] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 04/26/2018] [Indexed: 02/07/2023] Open
Abstract
In vitro maturation (IVM) is one of the most controversial aspects of assisted reproductive technology. Although it has been studied extensively, it is still not a conventional treatment option and is accepted as an alternative treatment. However, studies have shown that IVM can be used in almost all areas where in vitro fertilization (IVF) is used and it has a strong place in fertility protection and Ovarian Hyperstimulation syndrome management. The aim of this systematic review was to address all aspects of the current knowledge of IVM treatment together with the evolution of IVM and IVF.
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Affiliation(s)
- Şafak Hatırnaz
- Medicana International Hospital, In Vitro Fertilization Center, Samsun, Turkey
| | - Barış Ata
- Koç University Faculty of Medicine, Department of Obstetrics and Gynecology, In Vitro Fertilization Center, İstanbul, Turkey
| | | | - Michael Haim Dahan
- Mc Gill University Faculty of Medicine, Department of Obstetrics and Gynecology, Quebec, Canada
| | - Samer Tannus
- Mc Gill University Faculty of Medicine, Department of Obstetrics and Gynecology, Quebec, Canada
| | - Justin Tan
- Mc Gill University Faculty of Medicine, Department of Obstetrics and Gynecology, Quebec, Canada
| | - Seang Lin Tan
- Originelle Women and Reproductive Medicine Center, Clinic of Obstetrics and Gynecology, Montreal, Quebec, Canada
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McWilliam R, Leake RE, Coutts JR. Growth Factors in Human Ovarian Follicle Fluid and Growth Factor Receptors in Granulosa-Luteal Cells. Int J Biol Markers 2018; 10:216-20. [PMID: 8750648 DOI: 10.1177/172460089501000405] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The levels of oestradiol (E2), progesterone (P4), transforming growth factor a (TGFa), transforming growth factor β2 (TGFβ2), insulin-like growth factor I (IGF-I), platelet-derived growth factor AB (PDGF-AB) and epidermal growth factor (EGF) were measured in follicular fluids obtained from patients undergoing ovarian stimulation as part of an in vitro fertilisation program. Each of the substances was detected in all of the fluid samples tested, except TGFα (which was detected in 90% of samples tested), PDGF-AB (70%) and EGF (2%). Comparisons were made between each of these factors, follicular maturity, successful oocyte recovery and the outcome of fertilisation and embryo transfer. No statistically significant correlations were found. The presence of receptors for EGF, IGF-I and PDGF in extracts from granulosa-luteal cells isolated from follicular fluids was detected by means of Western blotting. The co-localisation of these growth factors and their receptors within the ovarian follicle suggests a likely role in control of follicular development.
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Affiliation(s)
- R McWilliam
- Division of Biochemistry and Molecular Biology, University of Glasgow
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Prochazka R, Blaha M, Němcová L. Significance of epidermal growth factor receptor signaling for acquisition of meiotic and developmental competence in mammalian oocytes†. Biol Reprod 2017; 97:537-549. [DOI: 10.1093/biolre/iox112] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/30/2017] [Indexed: 12/28/2022] Open
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Liu C, Wu GQ, Fu XW, Mo XH, Zhao LH, Hu HM, Zhu SE, Hou YP. The Extracellular Calcium-Sensing Receptor (CASR) Regulates Gonadotropins-Induced Meiotic Maturation of Porcine Oocytes. Biol Reprod 2015; 93:131. [PMID: 26490840 DOI: 10.1095/biolreprod.115.128579] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 10/14/2015] [Indexed: 12/16/2022] Open
Abstract
Gonadotropins and epidermal growth factor (EGF) play crucial roles in promoting oocyte maturation. The regulatory network downstream of these key factors is not well understood. The present study was designed to investigate the role of the calcium-sensing receptor (CASR) in porcine oocyte in vitro maturation. CASR expression was up-regulated in oocytes matured in gonadotropin-containing medium. Cortical distribution of CASR was enhanced with gonadotropins but not EGF. Supplementation of a CASR agonist (NPS R-568) in the gonadotropin (FSH and/or LH)-containing maturation medium significantly enhanced oocyte nuclear maturation. Addition of NPS2390, a CASR antagonist, compromised oocyte nuclear maturation. Furthermore, increased cortical distribution and decreased expression of CASR was observed after the NPS R-568 treatment. Oocytes treated with NPS R-568 had higher concentration of CYCLIN B1, decreased reactive oxygen species, and increased glutathione levels, indicative of advanced cytoplasmic maturation. In contrast, NPS2390 treatment compromised oocyte cytoplasmic maturation. A higher blastocyst formation rate after parthenogenetic activation was observed when oocytes were matured in the presence of the CASR agonist, NPS R-568. MAPK3/1 phosphorylation was increased during in vitro maturation and after NPS R-568 treatment, and decreased following CASR antagonist supplementation. Taken together, our data showed that the CASR is a gonadotropin-regulated factor that promotes porcine oocyte maturation in a MAPK-dependent manner.
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Affiliation(s)
- Cong Liu
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Guo-Quan Wu
- Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, China
| | - Xiang-Wei Fu
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Xian-Hong Mo
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Li-Hong Zhao
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Hong-Mei Hu
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Shi-En Zhu
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yun-Peng Hou
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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Yıldırım K, Vural MR, Küplülü S, Ozcan Z, Polat IM. The effects of EGF and IGF-1 on FSH-mediated in vitro maturation of domestic cat oocytes derived from follicular and luteal stages. Reprod Biol 2013; 14:122-7. [PMID: 24856471 DOI: 10.1016/j.repbio.2013.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 11/11/2013] [Accepted: 11/12/2013] [Indexed: 01/05/2023]
Abstract
The objective of this study was to evaluate the influence of epidermal growth factor (EGF) and insulin like growth factor-I (IGF-1) on the in vitro maturation of cat oocytes recovered from follicular and luteal stage ovaries. Oocytes from follicular (n=580) and luteal (n=209) stages were harvested and divided into four groups, which were cultured in FSH-mediated maturation medium supplemented with: (1) EGF alone (25ng/mL); (2) IGF-1 alone (100ng/mL); (3) EGF+IGF-1 (25ng/mL EGF+100ng/mL IGF-I); or (4) no growth factor (control). The proportion of follicular stage oocytes reaching the metaphase II stage was significantly higher than that of oocytes obtained at the luteal stage in both control and study groups (p<0.001). The percentages of oocytes reaching the metaphase II stage during the follicular period were 62.6% in control; 70.9% in EGF; 72.8% in IGF-1, and 78.1% in EGF+IGF-1 groups, whereas the respective values for gametes collected from luteal stage ovaries were 12.5%, 17.5%, 12.5%, and 16.9%. Additionally, the differences between the study and control groups were significant in the case of follicular stage oocytes. Finally, supplementing the maturation medium with EGF and/or IGF-1 significantly enhanced the meiotic maturation of oocytes recovered from follicular stage ovaries. The present study also demonstrated that the combination of EGF and IGF-I provides an additional or synergic effect on meiotic maturation of oocytes recovered from the follicular stage.
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Affiliation(s)
- Koray Yıldırım
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
| | - M Rıfat Vural
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
| | - Sükrü Küplülü
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
| | - Ziya Ozcan
- Department of Histology and Embriology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
| | - I Mert Polat
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
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Ruvolo G, Fattouh RR, Bosco L, Brucculeri AM, Cittadini E. New molecular markers for the evaluation of gamete quality. J Assist Reprod Genet 2013; 30:207-12. [PMID: 23371558 DOI: 10.1007/s10815-013-9943-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
PURPOSE Only 30 % of IVF cycles result in a pregnancy, so that multiple embryos need to be replaced, per treatment cycle, to increase pregnancy rates, resulting in a multiple gestation rate of 25 %. The use of new markers in the gamete selection, could reduce the number of the oocytes to be fertilized and embryos to be produced, but the tools to evidence the gamete competence remain unavailable and more studies are needed to identify bio-markers to select the best oocyte and sperm to produce embryos with higher implantation potentiality. METHODS To define oocyte competence, the apoptosis of the surrounding cumulus cells and the oxygen consumption rates for individual oocytes before fertilization seems to provide a non-invasive marker of oocyte competence and hence a quantitative assessment of the reproductive potential for the oocyte. The chromatin integrity seems to be used also as biological marker of sperm competence, together with the morphological evaluation of large vacuoles in the head. RESULTS The apoptosis rate of cumulus cells lower than 25 % and an higher oxygen consumption could be an evidence of an overall metabolic activity, related to a better fertilization ability and embryo cleavage quality. The apoptosis rate of the sperm chromatin, evaluated by direct Tunel in situ analysis, seems to be, also for the male gamete, a marker of competence and implantation potentiality, in particular when it is lower than 20 %. The evaluation of the presence of large vacuoles in the sperm head prior to perform ICSI seems to increase the implantation rate, but it is not associated to chromatin integrity. CONCLUSIONS The biological concept of competence appears unrelated to any morphological parameters, so that it is necessary to investigate new molecular markers in the gamete selection. Apoptosis of cumulus cells in the oocytes and spermatozoa, revealing the presence of large vacuoles, could help to determine the competence of the gamete to be fertilize.
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Affiliation(s)
- G Ruvolo
- Centro di Biologia della Riproduzione, Via V. Villareale 54, Palermo, Italy.
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Yu Y, Yan J, Li M, Yan L, Zhao Y, Lian Y, Li R, Liu P, Qiao J. Effects of combined epidermal growth factor, brain-derived neurotrophic factor and insulin-like growth factor-1 on human oocyte maturation and early fertilized and cloned embryo development. Hum Reprod 2012; 27:2146-59. [DOI: 10.1093/humrep/des099] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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13
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Pereira AF, Alcântara Neto AS, Albuquerque ES, Luciano MCS, Teixeira DIA, Freitas VJF, Melo LM. Goat oocyte production by standard or one-shot FSH treatments and quantitative analysis of transcripts for EGF ligands and its receptor after in vitro maturation. Reprod Domest Anim 2011; 47:244-51. [PMID: 21923881 DOI: 10.1111/j.1439-0531.2011.01845.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Hormonal ovarian stimulation may affect the success of embryo production by regulating transcripts in recovered cumulus-oocyte complexes (COCs). Here, in parallel to morphological classification and in vitro maturation (IVM) rate analysis, we investigated the expression of epidermal growth factor (EGF) and its receptor (EGFR) in oocytes and cumulus cells from goat COCs recovered by laparoscopy after standard [multi-dose follicle-stimulating hormone (FSH)] or one-shot (single dose FSH plus eCG) treatments. No differences were observed among the number of recovered and morphologically graded COCs or the IVM rates for both gonadotropic treatments. However, the standard protocol produced COCs with higher EGFR expression in the cumulus cells than the one-shot treatment. Additionally, EGF mRNA levels were less than EGFR mRNA levels, and they did not differ among COCs from both treatments. However, during maturation, the EGF transcripts increased in oocytes derived only from the standard protocol. Interestingly, IVM strikingly increased EGFR expression in oocytes and cumulus cells but not in oocytes that fail in first polar body extrusion, irrespective of hormonal treatment. These results appear to be related to the resumption of meiosis and suggest that EGF may act through the cumulus cells or directly on the oocyte receptor.
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Affiliation(s)
- A F Pereira
- Faculdade de Veterinária, Universidade Estadual do Ceará, Fortaleza-CE, Brazil
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Structural and functional changes linked to, and factors promoting, cytoplasmic maturation in mammalian oocytes. Reprod Med Biol 2011; 10:69-79. [PMID: 29699083 DOI: 10.1007/s12522-011-0079-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 02/21/2011] [Indexed: 02/04/2023] Open
Abstract
In most mammals, oocyte maturation is the final process of oogenesis, from the prophase of the first meiosis (germinal vesicle stage) to the metaphase of the second meiosis (MII), during which the oocyte acquires fertilizable competence as well as post-fertilization development competence. The nuclear and cytoplasmic maturation processes occur in synchrony but independently. Cytoplasmic maturation entails biochemical and structural changes in the cytoplasm, which give rise to oocytes capable of being fertilized and developing into embryos. Herein we review the literature and results from our own experiments on the structural and molecular events regulating cytoplasmic maturation in oocytes, concentrating on (1) the appropriate reorganization of active mitochondria and the endoplasmic reticulum, a structural and functional feature of cytoplasmic maturation, and (2) factors involved in regulatory mechanisms such as cumulus cell-oocyte gap junctional signaling, cumulus cell-oocyte bidirectional paracrine signaling, and the complex interactions of these signaling processes and follicular fluid constituents in the follicle environment.
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15
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Ben-Ami I, Komsky A, Bern O, Kasterstein E, Komarovsky D, Ron-El R. In vitro maturation of human germinal vesicle-stage oocytes: role of epidermal growth factor-like growth factors in the culture medium. Hum Reprod 2010; 26:76-81. [DOI: 10.1093/humrep/deq290] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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16
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Song HJ, Kang EJ, Maeng GH, Ock SA, Lee SL, Yoo JG, Jeon BG, Rho GJ. Influence of epidermal growth factor supplementation during in vitro maturation on nuclear status and gene expression of canine oocytes. Res Vet Sci 2010; 91:439-45. [PMID: 20888022 DOI: 10.1016/j.rvsc.2010.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 07/20/2010] [Accepted: 09/04/2010] [Indexed: 10/19/2022]
Abstract
This study evaluated the effect of epidermal growth factor (EGF) supplementation during in vitro maturation on the meiotic status and the expression of EGF receptor (EGFr), luteinizing hormone receptor (LHr) and gap junction protein α 5 (GJA5) in canine cumulus-oocyte-complexes (COCs). COCs of ≥110 μm diameter, exhibiting dark pigmentation and completely surrounded by three or more layers of cumulus cells collected from anestrus stage ovaries in natural cycle were matured in TCM-199 supplemented with 10% fetal bovine serum, 0.57 mM cysteine, 10 μg/ml LH and FSH, and different concentrations of EGF (0, 10 and 30 ng/ml). Oocytes cultured for 72 h were fixed to assess the nuclear maturation. Expression of EGFr, LHr and GAJ5 was assessed by immunocytochemistry and real-time PCR. Proportion of metaphase II status of oocytes cultured in in vitro maturation (IVM) medium supplemented with 10 ng/ml EGF for 72 h was significantly (P<0.05) higher than 0 and 30 ng/ml EGF supplemented IVM medium (9.8% vs. 6.5% and 5.2%). In both cumulus cells and oocytes, EGFr protein was undetectable, LHr protein level of expression was low and a strong expression of GJA5 protein was observed. The relative abundance (RA) of EGFr transcript revealed low levels and the LHr expression decreased steadily with addition of EGF. However it did not vary among different concentrations of EGF supplementation. The RA of GJA5 transcript exhibited lower level at 10 ng/ml EGF supplementation. In conclusion, the supplementation of 10 ng/ml EGF in IVM media exerted a positive influence on the progression of maturation to MII phase and the expression level of GJA5 at 72 h, but did not demonstrate any stimulatory role on the expression of EGFr and LHr during the maturation of the canine IVM oocytes.
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Affiliation(s)
- H J Song
- College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701, Republic of Korea
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17
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Zamah AM, Hsieh M, Chen J, Vigne JL, Rosen MP, Cedars MI, Conti M. Human oocyte maturation is dependent on LH-stimulated accumulation of the epidermal growth factor-like growth factor, amphiregulin. Hum Reprod 2010; 25:2569-78. [PMID: 20719813 DOI: 10.1093/humrep/deq212] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The LH surge promotes ovulation via activation of multiple signaling networks in the ovarian follicle. Studies in animal models have shown the importance of LH-induced activation of the epidermal growth factor (EGF)signaling network in critical peri-ovulatory events. We investigated the biological significance of regulatory mechanisms mediated by EGF-like growth factors during LH stimulation in humans. METHODS We characterized the EGF signaling network in mature human ovarian follicles using in vivo and in vitro approaches. Amphiregulin (AREG) levels were measured in 119 follicular fluid (FF) samples from IVF/ICSI patients. Biological activity of human FF was assessed using in vitro oocyte maturation, cumulus expansion and cell mitogenic assays. RESULTS AREG is the most abundant EGF-like growth factor accumulating in the FF of mature follicles of hCG-stimulated patients. No AREG was detected before the LH surge or before hCG stimulation of granulosa cells in vitro, demonstrating that the accumulation of AREG requires gonadotrophin stimulation. Epiregulin and betacellulin mRNA were detected in both human mural and cumulus granulosa cells, although at significantly lower levels than AREG. FF from stimulated follicles causes cumulus expansion and oocyte maturation in a reconstitution assay. Immunodepletion of AREG abolishes the ability of FF to stimulate expansion (P < 0.0001) and oocyte maturation (P < 0.05), confirming the biological activity of AREG. Conversely, mitogenic activity of FF remained after depletion of AREG, indicating that other mitogens accumulate in FF. FF from follicles yielding an immature germinal vesicle oocyte or from an oocyte that develops into an aberrant embryo contains lower AREG levels than that from follicles yielding a healthy oocyte (P = 0.008). CONCLUSIONS EGF-like growth factors play a role in critical peri-ovulatory events in humans, and AREG accumulation is a useful marker of gonadotrophin stimulation and oocyte competence.
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Affiliation(s)
- A M Zamah
- Department of Obstetrics and Gynecology and Reproductive Sciences, Division of Reproductive Endocrinology and Infertility, University of California San Francisco, 2356 Sutter Street, 7th Floor, San Francisco, CA 94115, USA.
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18
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Real-time qRT-PCR analysis of EGF receptor in cumulus-oocyte complexes recovered by laparoscopy in hormonally treated goats. ZYGOTE 2010; 19:127-36. [DOI: 10.1017/s0967199410000225] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SummaryOvarian stimulation with exogenous follicle stimulating hormone (FSH) has been used to increase the number of viable oocytes for laparoscopic oocyte recovery (LOR) in goats. The aim of this study was to evaluate the effect of two FSH protocols for ovarian stimulation in goats on the expression pattern of epidermal growth factor (EGF) receptor (EGFR) in cumulus–oocyte complexes (COCs) recovered by LOR. After real-time qRT-PCR analysis, expression profiles of morphologically graded COCs were compared prior to and after in vitro maturation (IVM) on a FSH protocol basis. The use of a protocol with higher number of FSH injections at a shorter interval resulted in GI/GII COCs with a higher level of EGFR expression in cumulus cells, but not in the oocyte, which was correlated with an elevated meiotic competence following IVM. Based on the maturation profile and EGFR expression patterns observed between groups, the morphological selection of COCs prior to IVM was not a good predictor of oocyte meiotic competence. Therefore, EGFR may be a good candidate marker for indirect prediction of goat oocyte quality. The IVM process of goat COCs increased the EGFR expression in oocytes and cumulus cells, which seemed to be strongly associated with the resumption of meiosis. In summary, differential EGFR expression in goat cumulus cells was associated with the in vivo prematuration process, and in turn, the upregulation in the entire COC was associated with IVM. Cause-and-effect relationships between such increased expression levels, particularly in the oocyte, and oocyte competence itself still need to be further investigated.
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Tkachenko OY, Delimitreva S, Isachenko E, Valle RR, Michelmann HW, Berenson A, Nayudu PL. Epidermal growth factor effects on marmoset monkey (Callithrix jacchus) oocyte in vitro maturation, IVF and embryo development are altered by gonadotrophin concentration during oocyte maturation. Hum Reprod 2010; 25:2047-58. [DOI: 10.1093/humrep/deq148] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Uhm S, Gupta M, Yang J, Chung HJ, Min T, Lee H. Epidermal growth factor can be used in lieu of follicle-stimulating hormone for nuclear maturation of porcine oocytes in vitro. Theriogenology 2010; 73:1024-36. [DOI: 10.1016/j.theriogenology.2009.11.029] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 11/10/2009] [Accepted: 11/16/2009] [Indexed: 10/19/2022]
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21
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Kiapekou E, Loutradis D, Mastorakos G, Bletsa R, Beretsos P, Zapanti E, Drakakis P, Antsaklis A, Kiessling AA. Effect of PRL on In Vitro Follicle Growth, In Vitro Oocyte Maturation, Fertilization and Early Embryonic Development in Mice. CLONING AND STEM CELLS 2009; 11:293-300. [DOI: 10.1089/clo.2008.0046] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Erasmia Kiapekou
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
- Bedford Stem Cell Research Foundation, Somerville, Massachusetts
| | - Dimitris Loutradis
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
| | - George Mastorakos
- Endocrine Unit, Second Department of Obstetrics and Gynecology, Aretaieion Hospital, University of Athens, Athens, Greece
| | - Ritsa Bletsa
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
| | - Panagiotis Beretsos
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
| | | | - Peter Drakakis
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
| | - Aristeidis Antsaklis
- First Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens, Athens, Greece
| | - Ann A. Kiessling
- Bedford Stem Cell Research Foundation, Somerville, Massachusetts
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22
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Effects of growth factors and granulosa cell co-culture on in-vitro maturation of oocytes. Reprod Biomed Online 2009; 19:165-70. [DOI: 10.1016/s1472-6483(10)60068-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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23
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Ling B, Feng DQ, Zhou Y, Gao T, Wei HM, Tian ZG. Effect of conditioned medium of mesenchymal stem cells on the in vitro maturation and subsequent development of mouse oocyte. ACTA ACUST UNITED AC 2008; 41:978-85. [PMID: 19039379 DOI: 10.1590/s0100-879x2008005000053] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Accepted: 10/17/2008] [Indexed: 11/22/2022]
Abstract
Mesenchymal stem cells (MSCs) secrete a variety of cytokines and growth factors in addition to self-renewal and multiple forms of differentiation. Some of these secreted bioactive factors could improve meiotic maturation in vitro and subsequent embryo developmental potential. The aim of the present study was to determine whether in vitro maturation (IVM) of mouse oocyte with or without cumulus cells could be improved by contact with conditioned medium (CM) of MSCs as well as the efficiency of CM to support follicular growth and oocyte maturation in the ovarian organ of mice cultured on soft agar. The developmental potential of matured oocyte was assessed by blastocyst formation after in vitro fertilization (IVF). Germinal vesicle stage oocytes with or without cumulus cells were subjected to IVM in either CM, Dulbecco's modified Eagle's medium (DMEM), alpha-minimum essential medium (alpha-MEM) or human tubal fluid (HTF). Approximately 120 oocytes were studied for each medium. CM produced a higher maturation rate (91.2%) than DMEM (54.7%), alpha-MEM (63.5%) and HTF (27.1%). Moreover, CM improved embryo development to blastocyst stage significantly more than DMEM and HTF (85 vs 7% and 41.7%, respectively) but there was no significant difference compared with alpha-MEM (85 vs 80.3%). The behavior of cortical granules of IVM oocytes cultured in CM revealed cytoplasmic maturation. Moreover, CM also supported preantral follicles growth well in organotypic culture on soft agar resulting in the maturation of 60% of them to developmentally competent oocytes. The production of estrogen progressively increased approximately 1-fold every other day during organ culture, while a dramatic 10-fold increase in progesterone was observed 17 h after human chorionic gonadotropin stimulus at the end of culture. Thus, CM is an effective medium for preantral follicle growth, oocyte maturation, and sequential embryo development.
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Affiliation(s)
- B Ling
- Department of Obstetrics and Gynecology, Anhui Provincial Hospital Affiliated, Anhui Medical University, Hefei 230001, China.
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24
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Singhal S, Prasad S, Singh B, Prasad JK, Gupta HP. Effect of including growth factors and antioxidants in maturation medium used for in vitro culture of buffalo oocytes recovered in vivo. Anim Reprod Sci 2008; 113:44-50. [PMID: 18620823 DOI: 10.1016/j.anireprosci.2008.05.078] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 05/17/2008] [Accepted: 05/30/2008] [Indexed: 10/22/2022]
Abstract
This study examined the effect of including one of two growth factors (100 ng/ml IGF-1 or 20 ng/ml EGF) in combination with one of two antioxidants (50 microM cysteamine or 50 microM beta-mercaptoethanol) in maturation, fertilization and subsequent development of buffalo oocytes. The oocytes were recovered by in vivo ovum pick-up technique from six Murrah buffalo heifers twice a week over a period of 16 weeks. Immediately after ovum pick-up oocytes recovered from six donors were allocated randomly to five different maturation treatments. The control treatment was the basic maturation medium (MM; TCM-199 supplemented with 10% FBS, 10 IU/ml LH, 0.5 microg/ml FSH, 1 microg/ml estradiol-17beta and 50 microg/ml gentamicin). The other four treatments consisted of the control maturation medium (MM) plus one combination of a growth factor and an antioxidant viz. IGF-1+cysteamine; IGF-1+beta-ME; EGF+cysteamine or EGF+beta-ME. The total number of oocytes assigned to each maturation treatment ranged from 31 to 66. After maturation in different maturation medium, media used for in vitro fertilization and subsequent development of embryo was same for all groups. Data were analysed using Chi-square test. The maturation rate observed for the growth factor plus antioxidant treatments was similar to that for the control (90.4%). The highest cleavage rate recorded in the IGF-1+cysteamine treatment (71.9%) which was significantly higher (P<0.05) than the IGF-1+beta-ME (45.2%) and EGF+beta-ME (46.4%) treatments, but not significantly differ from the control (63.8%) and EGF+cysteamine treatment (60.7%). The proportion of cleaved oocytes those developed to blastocyst stage was significantly higher in the IGF-1+cysteamine treatment (52.2%; P<0.05) than in the control (23.3%), the EGF+cysteamine (13.5%) or the EGF+beta-ME (7.7%) treatments, but did not differ significantly from the IGF-1+beta-ME (28.6%) treatment. Following non-surgical transfer of 15 embryos to 14 synchronized recipients, four became pregnant and only one recipient sustained the pregnancy as long as 4.5 months when spontaneous abortion occurred. It was concluded that supplementing the maturation medium with IGF-1+cysteamine improved the production of buffalo embryos significantly in vitro culture.
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Affiliation(s)
- Sumit Singhal
- Department of Animal Reproduction, Gynaecology & Obstetrics, College of Veterinary and Animal Sciences, G.B. Pant University of Agriculture & Technology, Pantnagar 263145, Uttarakhand, India
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25
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Li M, Liang CG, Xiong B, Xu BZ, Lin SL, Hou Y, Chen DY, Schatten H, Sun QY. PI3-kinase and mitogen-activated protein kinase in cumulus cells mediate EGF-induced meiotic resumption of porcine oocyte. Domest Anim Endocrinol 2008; 34:360-71. [PMID: 18023131 DOI: 10.1016/j.domaniend.2007.10.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 10/03/2007] [Accepted: 10/04/2007] [Indexed: 10/22/2022]
Abstract
Previous studies have shown that epidermal growth factor (EGF) has the ability to promote in vitro cultured porcine oocyte maturation. However, little is known about the detailed downstream events in EGF-induced meiotic resumption. We designed this study to determine the relationship of EGF, EGFR, phosphatidylinositol 3-kinase (PI3-kinase), MAPK, and germinal vesicle breakdown (GVBD) during oocyte maturation. Our results showed that GVBD in cumulus-enclosed oocytes (CEOs) but not in denuded oocytes (DOs) was induced by EGF in a dose-dependent manner, which indicated that cumulus cells but not oocyte itself were the main target for EGF-induced meiotic resumption. Furthermore, we found that MAPK in cumulus cells rather than in oocyte was activated immediately after EGF administration. To explore whether EGF exerts its functions through MAPK pathway, the activities of EGF receptor (EGFR) and MAPK were inhibited by employing AG1478 and U0126, respectively. Inhibition of MAPK blocked EGF-induced GVBD, whereas inhibition of EGFR prevented MAPK activation. Both AG1478 and U0126 could lead to the failure of EGF-induced GVBD singly. Notably, we found that LY294002, a specific inhibitor of PI3-kinase, effectively inhibited EGF-induced MAPK activation as well as subsequent oocyte meiotic resumption and this inhibition could not be reversed by adding additional EGF. Thus, PI3-kinase-induced MAPK activation in cumulus cells mediated EGF-induced meiotic resumption in porcine CEOs. Together, this study provides evidences demonstrating a linear relationship of EGF/EGFR, PI3-kinase, MAPK and GVBD and presents a relatively definitive mechanism of EGF-induced meiotic resumption of porcine oocyte.
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Affiliation(s)
- Mo Li
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Da Tun Road, Chaoyang, Beijing 100101, PR China
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26
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Wu J, Tian Q. Role of follicle stimulating hormone and epidermal growth factor in the development of porcine preantral follicle in vitro. ZYGOTE 2007; 15:233-40. [PMID: 17637104 DOI: 10.1017/s0967199407004194] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SummaryThe aim of the present study was to assess the role of follicle stimulating hormone (FSH), epidermal growth factor (EGF) or a combination of EGF and FSH on the in vitro growth of porcine preantral follicles, estradiol secretion, antrum formation, oocyte maturation and subsequent embryonic development. Porcine preantral follicles were cultured for 3 days in the absence or in the presence of FSH or EGF. Oocytes from these follicles were then matured, fertilized in vitro and embryos were cultured. Estradiol secretion and histological analysis of cultured follicles were also carried out. The results showed that when FSH, or a combination of EGF and FSH, was added to the culture medium, most of preantral follicles grew to antral follicles with high estradiol secretion and the oocytes from these antral follicles could mature, fertilize and develop to the blastocyst stage. Without FSH, or a combination of EGF and FSH, preantral follicles were unable to develop to the antral stage. Histology demonstrated that the resulting follicles were nonantral, estradiol production was reduced and none of their oocytes matured after in vitro maturation. The results indicate the essential role of FSH in promoting in vitro growth of porcine preantral follicle, estradiol secretion, antrum formation, oocyte maturation and subsequent embryonic development. EGF with FSH treatment of porcine preantral follicles improves the quality of oocytes, shown by a higher frequency of embryonic development.
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Affiliation(s)
- Ji Wu
- School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
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27
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Preis KA, Seidel GE, Gardner DK. Reduced oxygen concentration improves the developmental competence of mouse oocytes following in vitro maturation. Mol Reprod Dev 2007; 74:893-903. [PMID: 17192892 DOI: 10.1002/mrd.20655] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reduced atmospheric oxygen concentration is beneficial to embryo development; however, optimal oxygen concentration for oocyte maturation remains undetermined. Likewise, there is no consensus of appropriate medium supplementation during maturation. The objective of this study was to determine whether oxygen tension (20% or 5% O2) and epidermal growth factor (EGF) affect oocyte metabolism and subsequent embryo development. Cumulus-oocyte complexes (COCs) were collected from 28-day-old equine chorionic gonadotropin (eCG) primed or unprimed F1 (C57BL/6xCBA) mice. COCs were matured in defined medium in one of four groups: 20% O2, 20% O2 + EGF, 5% O2, 5% O2 + EGF. In vivo matured COCs were also collected for analysis. COCs from unprimed mice, matured in 5% O2 +/- EGF or 20% O2 + EGF had higher metabolic rates than COCs matured in 20% O2 (P < 0.05). COCs from primed mice had higher metabolic rates when matured in the presence of EGF, regardless of oxygen tension (P < 0.01). Oxygen uptake and mitochondrial membrane potential were higher for in vivo matured oocytes and oocytes matured under 5% O2 compared to oocytes matured under 20% O2 (P < 0.05). Blastocyst formation was not different between maturation groups (primed or unprimed); however, embryo cell numbers were 20-45% significantly higher when COCs were matured at 5% O2 (P < 0.05). Results suggest that oocytes matured in physiological concentrations of oxygen have improved development and metabolic activity, more closely resembling in vivo maturation. These findings have implications for oocyte maturation in both clinical and research laboratories.
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Affiliation(s)
- Kimberly A Preis
- Colorado Center for Reproductive Medicine, Englewood, Colorado 80113, USA
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28
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Stricker SA, Smythe TL. Differing mechanisms of cAMP- versus seawater-induced oocyte maturation in marine nemertean worms II. The roles of tyrosine kinases and phosphatases. Mol Reprod Dev 2006; 73:1564-77. [PMID: 16902949 DOI: 10.1002/mrd.20596] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Instead of blocking oocyte maturation as it does in most animals, cAMP causes oocytes of marine nemertean worms to initiate maturation (=germinal vesicle breakdown, "GVBD"). To characterize cAMP-induced GVBD in nemerteans, inhibitors of tyrosine kinase signaling were tested on Cerebratulus sp. oocytes that had been incubated in cAMP-elevating drugs versus seawater (SW) alone. Such tests yielded similar results for Src-like tyrosine kinase blockers, as the inhibitors prevented mitogen-activated protein kinase (MAPK) activation without stopping either GVBD or maturation-promoting factor (MPF) activation in both SW and cAMP-elevating treatments. Alternatively, genistein, a general tyrosine kinase antagonist, and piceatannol, an inhibitor of the tyrosine kinase Syk, reduced GVBD and MAPK/MPF activities in SW-, but not cAMP-induced maturation. Similarly, inhibitors of the human epidermal growth factor receptor-2 (HER-2) tyrosine kinase prevented GVBD and MAPK/MPF activations in oocytes treated with SW, but not with cAMP-elevating drugs. Antagonists of either protein tyrosine phosphatases (PTPs) or the dual-specificity phosphatase Cdc25 also reduced GVBD and MAPK/MPF activities in SW-treated oocytes without generally affecting cAMP-induced maturation. Collectively, these data suggest cAMP triggers GVBD via pathways that do not require MAPK activation or several components of tyrosine kinase signaling. In addition, such differences in tyrosine kinase cascades, coupled with the dissimilar patterns of Ser/Thr kinase signaling described in the accompanying study, indicate that nemertean oocytes are capable of utilizing multiple mechanisms to activate MPF during GVBD.
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Affiliation(s)
- Stephen A Stricker
- Department of Biology, University of New Mexcio, Albuquerque, 87131, USA.
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29
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Gall L, Boulesteix C, Ruffini S, Germain G. EGF-induced EGF-receptor and MAP kinase phosphorylation in goat cumulus cells during in vitro maturation. Mol Reprod Dev 2006; 71:489-94. [PMID: 15858794 DOI: 10.1002/mrd.20317] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
EGF has been shown to influence meiotic maturation and development competence of oocyte in various mammalian species. We previously reported, in goat, that the EGF receptor (EGF-R) was present both on cumulus cells and oocytes. Here, EGF-induced signaling was investigated during the in vitro maturation process in goat cumulus-oocyte complexes (COCs). Cumulus cells and oocytes were subjected to Western immunoblotting analysis using anti-MAP kinase, anti-phosphotyrosine, anti-phospho MAP kinase, and anti-phospho EGF-R antibodies. We demonstrated that treatment with EGF during the in vitro maturation process induced rapid tyrosine phosphorylation of EGF-R in a time and concentration dependent manner in cumulus cells. A similar pattern of activation by phosphorylation was observed for MAP kinase upon EGF stimulation. AG 1478, an inhibitor of the EGF kinase, suppressed EGF-stimulated phosphorylation of EGF-R and also affected the MAP kinase activation. Treatment with the MEK inhibitor PD 98059 abolished EGF-induced MAP kinase activation. We did not observe oocyte EGF-R phosphorylation in our experiments during the in vitro maturation process. Our data indicate, in goat cumulus cells, that activation of EGF-R by EGF triggers signaling through the MAP kinase pathway during in vitro maturation. This supports the hypothesis that the major site of action for EGF, that regulates oocyte maturation, is the cumulus cell.
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Affiliation(s)
- Laurence Gall
- Unité Biologie du Developpement et de la Reproduction, INRA, Jouy-en-Josas, France.
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30
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Asimakopoulos B, Schöpper B, Dawson A, Caglar GS, Vakalopoulos I, Al-Hasani S, Diedrich K, Nikolettos N. IGF-I and epidermal growth factor levels in follicular fluid of women undergoing controlled ovarian hyperstimulation using the multidose GnRH-antagonist protocol or the long GnRH-agonist protocol. J Endocrinol Invest 2006; 29:RC5-8. [PMID: 16794358 DOI: 10.1007/bf03344118] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The intrafollicular levels of IGF-I and epidermal growth factor (EGF) were studied in women undergoing controlled ovarian hyperstimulation using the multidose GnRH-antagonist protocol or the long agonist protocol, in an attempt to elucidate whether GnRH-antagonists affect the levels of the two growth factors. The follicular fluid concentration of IGF-I, EGF, estradiol and progesterone were detected in 68 women undergoing ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) cycles. There were no differences in intrafollicular concentrations of EGF and IGF-I in the two studied groups. Additionally, we found no correlation between the intrafollicular levels of IGF-I or EGF and the ICSI outcome. The intrafollicular levels of IGF-I were positively correlated with those of progesterone. In conclusion, the intrafollicular levels of IGF-I and EGF do not seem to be influenced by the stimulation protocol. The intrafollicular levels of both growth factors can not serve as prognostic markers for the ICSI outcome.
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Affiliation(s)
- B Asimakopoulos
- Laboratory of Physiology, School of Medicine, Democritus University of Thrace, 68100 Alexandroupolis, Greece
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Mehlmann LM. Stops and starts in mammalian oocytes: recent advances in understanding the regulation of meiotic arrest and oocyte maturation. Reproduction 2006; 130:791-9. [PMID: 16322539 DOI: 10.1530/rep.1.00793] [Citation(s) in RCA: 319] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mammalian oocytes grow and undergo meiosis within ovarian follicles. Oocytes are arrested at the first meiotic prophase, held in meiotic arrest by the surrounding follicle cells until a surge of LH from the pituitary stimulates the immature oocyte to resume meiosis. Meiotic arrest depends on a high level of cAMP within the oocyte. This cAMP is generated by the oocyte, through the stimulation of the G(s) G-protein by the G-protein-coupled receptor, GPR3. Stimulation of meiotic maturation by LH occurs via its action on the surrounding somatic cells rather than on the oocyte itself. LH induces the expression of epidermal growth factor-like proteins in the mural granulosa cells that act on the cumulus cells to trigger oocyte maturation. The signaling pathway between the cumulus cells and the oocyte, however, remains unknown. This review focuses on recent studies highlighting the importance of the oocyte in producing cAMP to maintain arrest, and discusses possible targets at the level of the oocyte on which LH could act to stimulate meiotic resumption.
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Affiliation(s)
- Lisa M Mehlmann
- Department of Cell Biology, University of Connecticut Health Center, 263 Farmington Ave., Farmington, Connecticut 06032, USA.
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32
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Conti M, Hsieh M, Park JY, Su YQ. Role of the epidermal growth factor network in ovarian follicles. Mol Endocrinol 2005; 20:715-23. [PMID: 16051667 DOI: 10.1210/me.2005-0185] [Citation(s) in RCA: 266] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The LH surge causes major remodeling of the ovarian follicle in preparation for the ovulatory process. These changes include reprogramming of granulosa cells to differentiate into luteal cells, changes in cumulus cell secretory properties, and oocyte maturation. This review summarizes published data in support of the concept that LH stimulation of ovarian follicles involves activation of a local epidermal growth factor (EGF) network. A model describing this property of LH signaling and its branching to other signaling modules is discussed. According to this model, LH activation of mural granulosa cells stimulates cAMP signaling, which, in turn, induces the expression of the EGF-like growth factors epiregulin, amphiregulin, and betacellulin. These growth factors function by activating EGF receptors in either an autocrine/juxtacrine fashion within the mural layer, or they diffuse to act on cumulus cells. Activation of EGF receptor signaling in cumulus cells, together with cAMP priming, triggers oocyte nuclear maturation and acquisition of developmental competence as well as cumulus expansion. This model has important implications for ovarian physiology and for the development of new strategies for the pharmacological control of ovulation and for gamete maturation in vitro.
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Affiliation(s)
- Marco Conti
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, California 94305-5317, USA.
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Kawamura K, Kawamura N, Mulders SM, Sollewijn Gelpke MD, Hsueh AJW. Ovarian brain-derived neurotrophic factor (BDNF) promotes the development of oocytes into preimplantation embryos. Proc Natl Acad Sci U S A 2005; 102:9206-11. [PMID: 15967989 PMCID: PMC1166611 DOI: 10.1073/pnas.0502442102] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Optimal development of fertilized eggs into preimplantation embryos is essential for reproduction. Although mammalian oocytes ovulated after luteinizing hormone (LH) stimulation can be fertilized and promoted into early embryos in vitro, little is known about ovarian factors important for the conditioning of eggs for early embryo development. Because LH interacts only with ovarian somatic cells, its potential regulation of oocyte functions is presumably mediated by local paracrine factors. We performed DNA microarray analyses of ovarian transcripts and identified brain-derived neurotrophic factor (BDNF) secreted by granulosa and cumulus cells as an ovarian factor stimulated by the preovulatory LH surge. Ovarian BDNF acts on TrkB receptors expressed exclusively in oocytes to enhance first polar body extrusion of oocytes and to promote the in vitro development of zygotes into preimplantation embryos. Furthermore, in vivo treatment with a Trk receptor inhibitor suppressed first polar body extrusion and the progression of zygotes into blastocysts. Thus, ovarian BDNF is important to nuclear and cytoplasmic maturation of the oocyte, which is essential for successful oocyte development into preimplantation embryos. Treatment with BDNF could condition the cultured oocytes for optimal progression into the totipotent blastocysts.
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Affiliation(s)
- Kazuhiro Kawamura
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA 94305-5317, USA
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Vlahos NF, Bankowski BJ, Zacur HA, Garcia JE, Wallach EE, Zhao Y. An oocyte donation protocol using the GnRH antagonist ganirelix acetate, does not compromise embryo quality and is associated with high pregnancy rates. Arch Gynecol Obstet 2005; 272:1-6. [PMID: 15838696 DOI: 10.1007/s00404-005-0726-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Accepted: 01/14/2005] [Indexed: 11/28/2022]
Abstract
PURPOSE To evaluate the effect of the GnRH antagonist, ganirelix acetate, on oocyte quality. METHODS Stimulation characteristics, implantation rates and clinical pregnancy rates were compared between 29 oocyte donors 21-31 years of age who underwent 31 cycles of ovarian stimulation with gonadotropins and ganirelix acetate, and 36 infertile couples of similar age range who underwent 51 cycles of ovarian stimulation using the same protocol. RESULTS A significantly lower number of embryos were transferred in the donor/recipient group as compared to the infertile group (2.32+/-0.54 vs. 2.82+/-0.71, P<0.05). In contrast, implantation and clinical pregnancy rates per transfer, were significantly higher in the donor/recipient group (38.1% vs. 10.4%, P<0.01) and (61.3% vs. 23.1%, P<0.05) respectively, as compared to the infertile group. CONCLUSIONS Incorporation of ganirelix acetate for pituitary suppression in stimulation protocols for oocyte donation is associated with high pregnancy rates suggesting that ganirelix acetate does not exert an adverse effect on oocyte or embryo quality.
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Affiliation(s)
- N F Vlahos
- Division of Reproductive Endocrinology & Infertility, The Johns Hopkins Hospital, 600 N. Wolfe Street/Phipps 249, Baltimore, 21287-1247, USA.
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Merlo B, Iacono E, Zambelli D, Prati F, Belluzzi S. Effect of EGF on in vitro maturation of domestic cat oocytes. Theriogenology 2004; 63:2032-9. [PMID: 15823358 DOI: 10.1016/j.theriogenology.2004.09.045] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Accepted: 09/26/2004] [Indexed: 10/26/2022]
Abstract
The objective of this study was to evaluate the influence of different concentrations of epidermal growth factor (EGF) on in vitro maturation of domestic cat oocytes. A total of 444 cat oocytes were matured in MSOF (maturation synthetic oviductal fluid) in the presence of varying EGF concentrations: (1) MSOF (control); (2) MSOF+10 ng/mL EGF (EGF10); (3) MSOF+25 ng/mL EGF (EGF25); and (4) MSOF+50 ng/mL EGF (EGF50). After IVM, oocytes were in vitro fertilized to verify the effect of adding EGF on cytoplasmic maturation. Cleavage rate was recorded and noncleaving oocytes were stained with Hoechst 33258 and examined to determine nuclear maturation rate. Cleaved zygotes were cultured in vitro and embryo stages were evaluated on days 6 and 7. There was no difference among groups in the total number of oocytes reaching the metaphase II (MII) stage (P>0.05). The EGF25 group had the highest (P<0.01) blastocyst yield (37.5%) and developmental competence (60.9%). Cleavage rate and resulting morulae and blastocysts on day 6 for EGF25 group were higher (P<0.01) than control and EGF50 groups. Although EGF did not significantly enhance nuclear maturation rate, it had a dose-related positive effect on cytoplasmic maturation, since the oocyte's ability to cleave and reach the blastocyst stage was improved at 25 ng/mL, with intermediate improvement at 10 ng/mL, but 50 ng/mL had no significant benefit. In conclusion, the addition of EGF to the maturation medium enhanced cytoplasmic maturation of cat oocytes in vitro.
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Affiliation(s)
- Barbara Merlo
- Veterinary Clinical Department, Obstetric-Gynecological Section, University of Bologna, via Tolara di Sopra 50, 40064 Ozzano Emilia (BO), Italy
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Dadi TD, Li MW, Lloyd KCK. Expression Levels of EGF, TGF-α, and EGF-R Are Significantly Reduced in Pre-Implantation Cloned Mouse Embryos. CLONING AND STEM CELLS 2004; 6:267-83. [PMID: 15671673 DOI: 10.1089/clo.2004.6.267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Tedla D Dadi
- Center for Comparative Medicine, School of Veterinary Medicine, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
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O'Donnell JB, Hill JL, Gross DJ. Epidermal growth factor activates cytosolic [Ca2+] elevations and subsequent membrane permeabilization in mouse cumulus-oocyte complexes. Reproduction 2004; 127:207-20. [PMID: 15056787 DOI: 10.1530/rep.1.00027] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The role of epidermal growth factor (EGF) in the maturation of mammalian oocytes is well known but not well characterized. It is known that EGF enhances oocyte maturation in vitro and that EGF stimulation of cumulus-oocyte complexes (COCs) induces pulsatile Ca(2+) efflux from the cell complex. By use of quantitative Fura-2 imaging, EGF-stimulated changes in intracellular [Ca(2+)] in germinal vesicle stage murine COCs are shown to occur in a subpopulation of cumulus cells that interact cooperatively within individual COCs. Oocytes fail to respond to EGF stimulus. In many of the cumulus cells responding with a rise in intracellular [Ca(2+)], a concomitant permeabilization of the plasma membrane is found. Neither cumulus cells of control COCs nor those that show a rise in intracellular [Ca(2+)] in response to calcium ionophore treatment display a similar membrane permeabilization, although those cells responding with a prolonged [Ca(2+)] increase in response to thimerosal or thapsigargin do display plasma membrane permeabilization. Thus, EGF stimulation of mammalian COCs activates release of Ca(2+) from intracellular stores of cumulus cells, the depletion of which activates permeabilization of the plasma membrane. This membrane permeabilization leads to loss of cell contents and presumptive cumulus cell death. This catastrophic EGF-induced plasma membrane permeabilization of individual cumulus cells within a COC leads to pulsatile Ca(2+) efflux as previously seen, and may lead to improved cumulus cell expansion during COC maturation.
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Affiliation(s)
- John B O'Donnell
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Lederle GRC, 710 N. Pleasant Street, Amherst, Massachusetts 01003, USA
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Gall L, Chene N, Dahirel M, Ruffini S, Boulesteix C. Expression of epidermal growth factor receptor in the goat cumulus-oocyte complex. Mol Reprod Dev 2004; 67:439-45. [PMID: 14991735 DOI: 10.1002/mrd.20040] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
It has been previously reported that epidermal growth factor (EGF) influences meiotic maturation and development competence of oocytes in various mammalian species. The present study was undertaken to analyze the expression of the gene encoding the EGF-receptor (EGF-R) in the goat cumulus-oocyte complex during meiotic competence acquisition. Expression of EGF-R mRNA was evaluated by PCR on reverse transcribed mRNA from follicular cells and oocytes, using EGF-R specific primers designed from human cDNA. The presence of the EGF-R transcript was evidenced in follicular cells as well as in meiotically competent and incompetent oocytes. Western blot analysis performed with specific anti EGF-R antibody revealed in meiotically competent and incompetent oocytes and in follicular cells a 170 kD polypeptide corresponding to the goat EGF-R protein. In oocytes the amount of EGF-R increased with meiotic competence acquisition. EGF-R distribution was examined by indirect immunofluorescence on frozen sections of cumulus-oocyte complexes (COCs). EGF-R immunoreactivity was observed in cumulus cells and in oocytes. Staining appeared to be confined to the periphery of the cells for both oocytes and cumulus cells. In this study, we identified the main component required for signaling via EGF-R in the goat oocyte and in follicular cells. These results suggest a possible involvement of EGF in the regulation of follicular growth and oocyte maturation in goat.
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Affiliation(s)
- Laurence Gall
- Unité de Biologie du Développement et de la Reproduction, INRA, Jouy-en-Josas, France.
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Nandi S, Ravindranatha BM, Gupta PSP, Raghu HM, Sarma PV. Developmental competence and post-thaw survivability of buffalo embryos produced in vitro: effect of growth factors in oocyte maturation medium and of embryo culture system. Theriogenology 2003; 60:1621-31. [PMID: 14580645 DOI: 10.1016/s0093-691x(03)00148-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The present study was conducted to examine the effects of supplementation to IVM medium of epidermal growth factor (EGF), fibroblast growth factor (FGF) and vasoactive intestinal peptide (VIP) along with pregnant mare serum gonadotrophin (PMSG) on oocyte maturation and cleavage of buffalo embryos (experiment 1). The developmental competence of cleaved embryos cultured in either a complex co-culture system (TCM-199+10% serum+oviduct cell monolayer) or defined media (a) modified form of synthetic oviductal fluid (mSOF) was evaluated (experiment 2). The post-thaw morphology and survivability of frozen blastocysts developed from embryos cultured either in complex or defined medium was compared (experiment 3). Aspirated oocytes were cultured in maturation medium (TCM-199+PMSG (40 IU/ml-control)) supplemented with EGF (20 ng/ml), FGF (20 ng/ml) and VIP (20 ng/ml), either alone or in combination, in a CO(2) incubator at 38.5 degrees C for 24h. Maturation rate was assessed and oocytes were inseminated in vitro with frozen-thawed sperm processed in Brackett and Oliphant (BO) medium. The cleaved embryos were cultured either in complex co-culture system or mSOF. Results suggested that EGF had more beneficial effect on buffalo oocyte maturation, and embryo cleavage than FGF. Addition of VIP to the oocyte maturation medium did not improve the results. Blastocyst yields from buffalo oocytes were significantly higher in a complex co-culture system than in defined media (mSOF) when oocytes were matured in presence of EGF either alone or in combination with FGF and VIP. The mean percent of morphologically normal blastocysts after thawing and their survivability were significantly higher in blastocysts obtained from embryos cultured in mSOF than those cultured in complex co-culture system.
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Affiliation(s)
- S Nandi
- National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore 560 030, India
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Raghu HM, Nandi S, Reddy SM. Effect of insulin, transferrin and selenium and epidermal growth factor on development of buffalo oocytes to the blastocyst stage in vitro in serum-free, semidefined media. Vet Rec 2002; 151:260-5. [PMID: 12233827 DOI: 10.1136/vr.151.9.260] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The in vitro development of buffalo oocytes up to the blastocyst stage was studied in serum-free, semidefined media containing bovine serum albumin, follicle-stimulating hormone (FSH), insulin, transferrin and selenium (ITS) and epidermal growth factor (EGF). In experiment 1, oocytes aspirated from abattoir-derived ovaries were cultured in eight serum-free, semidefined culture media containing different combinations of these four factors. In experiment 2, the maturation of buffalo oocytes and the development of the embryos were compared in a complex co-culture system and in the serum-free, semidefined media. Supplementation with FSH and EGF significantly (P < 0.05) increased the maturation rates of buffalo oocytes, and the yield of blastocysts was higher (P < 0.05) in media containing EGF and ITS. The yield of blastocysts was lower in the serum-free semidefined media (P < 0.05) than in the complex co-culture system.
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Affiliation(s)
- H M Raghu
- University of Agricultural Sciences, Hebbal, Bangalore, Karnataka, India
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Goff AK, Yang Z, Cortvrindt R, Smitz J, Miron P. Protein synthesis during maturation of bovine oocytes, effect of epidermal growth factor. Reprod Domest Anim 2001; 36:19-24. [PMID: 11305481 DOI: 10.1046/j.1439-0531.2001.00263.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The objective of this study was to determine whether epidermal growth factor (EGF) affected protein synthesis in oocytes during maturation. Initially, the effect of EGF on oocyte maturation was examined to ensure that there was a beneficial effect of EGF in the protein-free maturation medium used in these studies. Results showed that the presence of EGF during maturation significantly enhanced cleavage rate and development to the blastocyst stage. Development after maturation in the presence of EGF was similar to that seen in medium containing serum, luteinizing hormone, follicle-stimulating hormone and estradiol. Protein synthesis was examined in immature oocytes and after 16 or 24 h maturation. Oocytes from each group were labelled by incubation for 4 h with 35S-methionine, the proteins were then separated by two-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Between 400 and 500 proteins could be separated using this method and marked changes in protein synthesis was observed during maturation. Changes in eight different proteins were observed when protein patterns from oocytes matured for 16 h with and without EGF were compared. These results suggest that EGF plays a physiological role in oocyte maturation and identification of the proteins induced by EGF could be important for improving our understanding of oocyte maturation in vitro.
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Affiliation(s)
- A K Goff
- CRRA, Faculty of Veterinary Medicine, University of Montréal, St-Hyacinthe, Canada
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Kim BK, Lee SC, Kim KJ, Han CH, Kim JH. In vitro maturation, fertilization, and development of human germinal vesicle oocytes collected from stimulated cycles. Fertil Steril 2000; 74:1153-8. [PMID: 11119743 DOI: 10.1016/s0015-0282(00)01617-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVE To evaluate whether germinal vesicle (GV) oocytes from stimulated cycles can be a source of embryos. DESIGN In vitro model study. SETTING Specialized laboratory of women's clinic. PATIENT(S) Women in whom oocytes were retrieved at the GV stage. INTERVENTION(S) After culture of GV oocytes in the modified TLP medium with human follicular fluid, oocytes that reached the metaphase II stage underwent ICSI. Potential of fertilization and subsequent cleavage of in vitro-matured oocytes was compared with that of an in vivo-matured control. MAIN OUTCOME MEASURE(S) Maturation rate, rate of pronuclei formation, and developmental activity. RESULT(S) The maturation rate of GV oocytes from follicles primed with gonadotropin was not affected by the presence or absence of cumulus. However, the maturation was more synchronous in oocytes with cumulus than in those without cumulus. Proportions of oocytes with two pronuclei and embryos cleaved to the 16-cell stage after ICSI were significantly lower in the oocytes matured in vitro than in the oocytes matured in vivo. CONCLUSION(S) Human GV oocytes from stimulated ovaries can be matured, fertilized, and developed in vitro. Production of embryos from GV oocytes will increase the opportunity for achieving pregnancy.
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Affiliation(s)
- B K Kim
- Department of Biology, Dongeui University, Pusan, South Korea.
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Sakaguchi M, Dominko T, Leibfried-Rutledge ML, Nagai T, First NL. A combination of EGF and IGF-I accelerates the progression of meiosis in bovine follicular oocytes in vitro and fetal calf serum neutralizes the acceleration effect. Theriogenology 2000; 54:1327-42. [PMID: 11192191 DOI: 10.1016/s0093-691x(00)00439-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effects of a combination of EGF and IGF-I (GFs) on the progress of meiosis and on their developmental competence were examined in cumulus-enclosed bovine oocytes. Exposure to GFs in serum-free, 0.3% PVP-containing maturation medium significantly (P<0.05) increased the frequency of oocytes with the first polar body (PB) at 16 h of culture and decreased those with PB at 20 h. The cleavage rates of PB-extruded oocytes after fertilization were not affected by treatment of GFs during maturation culture, and blastocyst yield was not improved by GFs treatment. Although replacement of PVP from GFs-containing medium with fatty acid-free BSA did not affect the timing of PB extrusion, replacement with 10% FCS neutralized the acceleration effects of GFs. Replacement for macromolecule in maturation medium did not improve blastocyst yield of PB-extruded oocytes after fertilization. These results indicate that the progression of meiosis in bovine oocytes with cumulus cells is accelerated by exposure to GFs in serum-free maturation medium but their developmental competence is not improved, and that the acceleration effects on the progress of meiosis is neutralized by the presence of FCS in maturation medium with no improvement of developmental competence after in vitro fertilization.
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Affiliation(s)
- M Sakaguchi
- Laboratory of Animal Reproduction, Tohoku National Agricultural Experiment Station, Morioka, Iwate, Japan.
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Abeydeera LR, Wang WH, Cantley TC, Rieke A, Murphy CN, Prather RS, Day BN. Development and viability of pig oocytes matured in a protein-free medium containing epidermal growth factor. Theriogenology 2000; 54:787-97. [PMID: 11101038 DOI: 10.1016/s0093-691x(00)00390-3] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This study examined the ability of epidermal growth factor (EGF) to improve the developmental competence of pig oocytes matured in a protein-free (PF) in vitro maturation (IVM) system. Oocyte maturation was done in one of three media: 1. PF-TCM: tissue culture medium (TCM) 199 + 0.1% polyvinylalcohol (PVA); 2. PF-TCM+EGF: PF-TCM + 10 ng/ml EGF; and 3. +ve CONT: North Carolina State University (NCSU) 23 medium + 10% porcine follicular fluid. All media contained 0.57 mM cysteine. Hormonal supplements, 0.5 microg/mL LH and 0.5 microg/mL FSH, were present only for the first half (20 to 22 h) of the culture period. After maturation, oocytes were co-incubated with frozen-thawed spermatozoa for 5 to 6 h and transferred to embryo culture medium, NCSU 23 containing 0.4% BSA, for 144 h. In Experiment 1, differences in cumulus expansion were observed for oocytes matured in +ve CONT (Category 4), PF-TCM (Category 2) and PF-TCM+EGF (Category 3). However, no significant differences in nuclear maturation to metaphase II stage were observed. In Experiment 2, no differences in fertilization parameters were observed. Significant (P < 0.01) differences in cleavage rates were observed among the three media for a proportion of the oocytes matured (52, 60 and 69% in PF-TCM, PF-TCM+EGF, and +ve CONT, respectively). Oocytes matured in PF-TCM showed the lowest (P < 0.01) blastocyst development (22%). However, the same rate of blastocyst development was obtained for +ve CONT (37%) and PF-TCM+EGF (37%). Blastocyst cell numbers were significantly higher when oocytes were matured in the presence of EGF (26 vs. 37 to 41). In Experiment 3, oocytes matured in PF-TCM+EGF had a significantly (P < 0.05) higher intracellular glutathione (GSH) concentration (5.9 vs. 11.4 pmol/oocyte) compared with PF-TCM. Twenty-two of 25 embryo transfer recipients became pregnant (Experiment 4). Four animals returned to estrus in within 60 days. Six pregnant animals slaughtered at 26 to 45 days had 43 fetuses (range: 4 to 12) and the remaining 12 animals farrowed 82 piglets (range: 3 to 12). These results indicate that EGF enhances the developmental competence of pig oocytes matured in a protein-free culture medium which is correlated with higher GSH level in oocytes. Birth of piglets indicate that embryos derived from oocytes matured in the presence of EGF are viable.
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Affiliation(s)
- L R Abeydeera
- Department of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
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Hernandez ER. Embryo implantation and GnRH antagonists: embryo implantation: the Rubicon for GnRH antagonists. Hum Reprod 2000; 15:1211-6. [PMID: 10831542 DOI: 10.1093/humrep/15.6.1211] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
When gonadotrophin-releasing hormone (GnRH) was discovered, the agonist and antagonist of GnRH were developed to control the release of FSH and LH by the gonadotrophs. More than 10 years of research were needed to develop a GnRH antagonist free of histamine release. Recent studies have shown that these GnRH antagonists are effective in preventing a rise in LH during ovarian stimulation in IVF. However, a decrease in ongoing pregnancies seems to suggest that implantation rates per transferred embryo are reduced in GnRH antagonist-stimulated cycles. In my opinion, these data highlight an area less well known to clinicians: the role of the GnRH antagonist at the cellular level in extrapituitary tissues. There are sufficient data in the literature suggesting that GnRH antagonist is an inhibitor of the cell cycle by decreasing the synthesis of growth factors. Given that, for folliculogenesis, blastomere formation and endometrium development, mitosis is everything; the interaction between the GnRH antagonist and the GnRH receptor (present in all these cells and tissues) may compromise the mitotic programme of these cells. This is the Rubicon for the GnRH antagonist: to demonstrate irrevocably that, at the minimal doses necessary to suppress LH release, it does not affect processes such as implantation, embryo development and folliculogenesis.
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Affiliation(s)
- E R Hernandez
- Clinica de Reproduccion Asistida FIV-Madrid and Instituto de Bioquimica (CSIC-UCM), C/Alvarez de Baena 4, 28006 Madrid, Spain.
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Procházka R, Srsen V, Nagyová E, Miyano T, Flechon JE. Developmental regulation of effect of epidermal growth factor on porcine oocyte-cumulus cell complexes: nuclear maturation, expansion, and F-actin remodeling. Mol Reprod Dev 2000; 56:63-73. [PMID: 10737968 DOI: 10.1002/(sici)1098-2795(200005)56:1<63::aid-mrd8>3.0.co;2-d] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Epidermal growth factor (EGF) efficiently stimulates expansion of mouse and rat oocyte-cumulus complexes (OCC). Contradictory data have been published by several laboratories about the ability of EGF to stimulate expansion of porcine OCC. We assumed that these contradictions may have resulted from heterogeneous conditions used for isolation, culture, and assessment of OCC. The present experiments were designed to test the hypothesis that porcine OCC acquire the ability to synthesize hyaluronic acid (HA) and undergo expansion following EGF-stimulation gradually during the growth of follicles. For this reason, we isolated OCC from follicles of different sizes and assessed quantity of produced HA and proportions of expanding OCC after stimulation by EGF. In addition, we assessed in those OCC changes in morphology of cumulus cells and assembly of F-actin microfilaments, which are necessary for expansion to occur. Finally, nuclear maturation of EGF-stimulated OCC was assessed and its relationship with occurrence of expansion was evaluated. In all experiments, OCC stimulated with FSH were used as positive controls. The results showed that EGF did not stimulate production of HA, rearrangement of F-actin and expansion in OCC isolated from small follicles (<4 mm in diameter). OCC isolated from large preovulatory follicles (6-7 mm in diameter and PMSG-stimulated follicles) underwent efficient expansion when stimulated by EGF (93% and 100%, respectively). EGF dramatically stimulated total production of HA in these OCC and its retention in extracellular matrix of the expanding cumulus. Cumulus cells of the large OCC underwent essential changes of their morphology and extensive rearrangement of F-actin microfilaments following stimulation with EGF. Interestingly, EGF enhanced nuclear maturation of OCC isolated from both small and large follicles, which suggest diversity of signaling pathways controlling maturation and expansion. FSH caused cumulus expansion, F-actin remodeling, and enhancement of oocyte nuclear maturation in OCC originated from both small and large follicles. We conclude that EGF can stimulate expansion of porcine OCC in vitro; however, only of those isolated from large follicles. This indicates that EGF may have a physiological role in regulation of porcine cumulus expansion in preovulatory follicles, presumably as a mediator of signals elicited by the LH surge.
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Affiliation(s)
- R Procházka
- Academy of Sciences of the Czech Republic, Institute of Animal Physiology and Genetics, Libĕchov, Czech Republic.
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47
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De La Fuente R, O'Brien MJ, Eppig JJ. Epidermal growth factor enhances preimplantation developmental competence of maturing mouse oocytes. Hum Reprod 1999; 14:3060-8. [PMID: 10601097 DOI: 10.1093/humrep/14.12.3060] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The objective of this study was to determine whether epidermal growth factor (EGF) promotes nuclear and cytoplasmic maturation of mouse oocytes grown in vivo or in vitro. In-vivo-grown oocytes were isolated at the germinal vesicle (GV) stage from gonadotrophin-primed (PR) or -unprimed (UPR) 22-day-old mice before in-vitro maturation (IVM). In-vitro-grown (IVG) oocytes were isolated from preantral follicles of 12-day-old mice and grown in vitro without gonadotrophins for 10 days before maturation (IVG/IVM oocytes). IVM and IVG/IVM oocytes were matured in medium supplemented with either EGF (10 ng/ml), follicle stimulating hormone (FSH) (100 ng/ml), EGF plus FSH, or with neither ligand (control). When oocyte-cumulus cell complexes were isolated from PR and UPR mice, IVM with EGF (10 ng/ml), alone or in combination with FSH (100 ng/ml), increased (P < 0.05) the incidence of nuclear maturation to metaphase II. Cytoplasmic maturation of oocytes from PR females, manifested as increased frequency of cleavage to the 2-cell stage and development to the blastocyst stage, was also enhanced with EGF (P < 0.05). Moreover, EGF increased the number of cells per blastocyst, but only in the absence of FSH (P < 0.01). In contrast, EGF, FSH, or EGF plus FSH did not affect the percentage of oocytes from UPR mice completing preimplantation development, but did increase the number of cells per blastocyst. These ligands also increased the proportion of IVG oocytes reaching metaphase II (53-57%) compared with controls (25%; P < 0.05). EGF alone or in combination with FSH increased (P < 0.05) the frequency of blastocyst formation (23% and 28%, respectively) compared with controls (13%). EGF treatment of maturing IVG oocytes produced blastocysts with more cells than other IVG groups (P < 0.05). It is concluded that gonadotrophins in vivo increase the sensitivity or responsiveness of cumulus cell-enclosed oocytes to EGF, thereby promoting both nuclear and cytoplasmic maturation. However, oocyte-granulosa cell complexes grown in vitro become responsive to EGF without gonadotrophin treatment. Thus, nuclear and cytoplasmic maturation of IVG oocytes is promoted by EGF treatment during meiotic maturation.
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Schramm RD, Bavister BD. A macaque model for studying mechanisms controlling oocyte development and maturation in human and non-human primates. Hum Reprod 1999; 14:2544-55. [PMID: 10527985 DOI: 10.1093/humrep/14.10.2544] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A model to study mechanisms controlling nuclear and cytoplasmic maturation of primate oocytes is being developed in our laboratory. The high incidence of pregnancy failure in women following in-vitro fertilization (IVF) may be partly attributed to inadequate cytoplasmic maturation of oocytes. Advancement of knowledge of mechanisms controlling primate oocyte maturation would have important implications for treatment of human infertility, and would potentially increase numbers of viable non-human primate embryos for biomedical research. Use of a non-human primate model to study oocyte and embryo biology avoids legal, ethical and experimental limitations encountered in a clinical situation. Using this model, the meiotic and developmental capacity of oocytes from three sources have been compared: (i) in-vivo matured oocytes from monkeys stimulated with follicle-stimulating hormone (FSH) and human chorionic gonadotrophin, (ii) in-vitro matured oocytes from monkeys primed with FSH, and (iii) in-vitro matured oocytes from non-stimulated monkeys. This work demonstrates that oocyte developmental competence is likely acquired both during follicle development, before meiotic resumption, and during meiotic progression, concurrent with nuclear maturation. Potential causes of developmental failure of in-vitro matured oocytes, implications for human infertility, and future strategies to study the regulation of primate oocyte maturation are discussed.
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Affiliation(s)
- R D Schramm
- Wisconsin Regional Primate Research Center, 1223 Capitol Court, Madison, WI 53715, USA
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Ng ST, Chang TH, Wu TC. Prediction of the rates of fertilization, cleavage, and pregnancy success by cumulus-coronal morphology in an in vitro fertilization program. Fertil Steril 1999; 72:412-7. [PMID: 10519609 DOI: 10.1016/s0015-0282(99)00290-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To examine the relation between the grading of cumulus-coronal morphology at oocyte retrieval and the rates of fertilization, cleavage, and pregnancy success in IVF-ET cycles. DESIGN Retrospective study. SETTING University-affiliated medical center. PATIENT(S) Infertile women who underwent IVF-ET treatment. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Fertilization and cleavage of the oocytes and the pregnancy outcome. RESULT(S) Mature grade 3 cumulus-oocyte complexes (COCs) constituted the highest percentage among all grades and had a higher fertilization rate than COCs of other grades (77% versus 65%, 43%, and 28% for grades 2, 1, and 4, respectively). The cleavage and polyspermy rates did not correlate with cumulus-coronal morphology grading. The pregnancy rate was higher in cycles with >50% grade 3 COCs than in cycles with < or =50% grade 3 COCs (32% versus 16%). In cycles with >80% grade 3 COCs, the pregnancy rate was 57%. The correlation between the percentage of grade 3 COCs and the pregnancy rate was independent of patient age and the number of COCs retrieved. CONCLUSION(S) The cumulus-coronal morphology grade correlates with the fertilization rate but not with the cleavage or polyspermy rate. In vitro fertilization cycles that have a greater percentage of grade 3 COCs have an increased chance of resulting in pregnancy. The cumulus-coronal morphology grade predicts pregnancy success in IVF-ET cycles.
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Affiliation(s)
- S T Ng
- Department of Obstetrics and Gynecology, University of California-Los Angeles School of Medicine, 90095-1740, USA
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Park KW, Choi SH, Song XX, Funahashi H, Niwa K. Production of plasminogen activators (PAs) in bovine cumulus-oocyte complexes during maturation in vitro: effects of epidermal growth factor on production of PAs in oocytes and cumulus cells. Biol Reprod 1999; 61:298-304. [PMID: 10377062 DOI: 10.1095/biolreprod61.1.298] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We examined whether plasminogen activators (PAs) are produced by bovine cumulus-oocyte complexes (COCs) during maturation in vitro. The effects of epidermal growth factor (EGF) on production of PAs in oocytes and cumulus cells were also examined. When COCs were cultured for 24 h with 30 ng/ml EGF, three plasminogen-dependent lytic zones (58.5 +/- 3.5 kDa, 79.0 +/- 3.0 kDa, and 113.5 +/- 6.5 kDa) were observed. Addition of amiloride, a competitive inhibitor of urokinase-type PA (uPA), to the zymogram eliminated the activity of the 58.5 +/- 3.5-kDa zone, suggesting that this band is a uPA. However, since the activity of the remaining two bands was not eliminated, it was suggested that the 79.0 +/- 3.0-kDa band is a tissue-type PA (tPA) and the 113.5 +/- 6.5-kDa band is possibly a tPA-PA inhibitor (tPA-PAI) complex. In COCs before culture, however, no activity of PAs was detected. At 6 h of culture, the same level of uPA activity was detected in COCs cultured both in the absence and in the presence of EGF. The uPA activity was increased at 12 h of culture but without further increase at 24 h of culture, with higher activity in the presence than in the absence of EGF. The activity of tPA and tPA-PAI was first detected at 24 h of culture in the absence of EGF. In the presence of EGF, however, some activity of tPA-PAI was detected at 12 h of culture. At 24 h of culture, the activity of all PAs was detected in cumulus cells, but only uPA activity was detected in oocytes, with higher activity in the presence than in the absence of EGF. The uPA activity in oocytes was not detected when they were cultured without cumulus cells in either the presence or absence of EGF, although cumulus expansion was stimulated by EGF, exhibiting a time-course similar to that observed in PA production. These results suggest that uPA, tPA, and tPA-PAI are all produced by bovine COCs, but only uPA by oocytes, during maturation in vitro. However, cumulus cells play an essential role or roles in the production of uPA by oocytes, and EGF enhances the roles of cumulus cells.
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Affiliation(s)
- K W Park
- The Graduate School of Natural Science and Technology and Faculty of Agriculture, Okayama University, Okayama 700-8530, Japan
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