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Review: Role and regulatory mechanism of inhibin in animal reproductive system. Theriogenology 2023; 202:10-20. [PMID: 36878034 DOI: 10.1016/j.theriogenology.2023.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 02/14/2023] [Accepted: 02/15/2023] [Indexed: 03/03/2023]
Abstract
Inhibin (INH) is a glycoprotein hormone secreted by the gonads that inhibit the synthesis and secretion of follicle-stimulating hormone (FSH). Increasing evidence indicates that INH plays a significant role in the development of the reproductive system including follicle development, ovulation rate, corpus luteum formation and ablation, steroid hormone synthesis and spermatogenesis, subsequently affecting the reproductive capacity of animals such as litter size and egg production. There are currently three main views on how INH inhibits FSH synthesis and secretion: influencing the activity of adenylate cyclase, the expression of follicle-stimulating hormone receptor or gonadotropin-releasing hormone receptor, and the competition system of inhibin-activin. This review discusses the current findings on the structure, function, and mechanism of action of INH in the reproductive system of animals.
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Shakeel M, Yoon M. Functions of somatic cells for spermatogenesis in
stallions. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2022; 64:654-670. [PMID: 35969700 PMCID: PMC9353347 DOI: 10.5187/jast.2022.e57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/20/2022]
Abstract
Spermatogenesis and testis development are highly structured physiological
processes responsible for post-pubertal fertility in stallions. Spermatogenesis
comprises spermatocytogenesis, meiosis, and spermiogenesis. Although germ cell
degeneration is a continuous process, its effects are more pronounced during
spermatocytogenesis and meiosis. The productivity and efficiency of
spermatogenesis are directly linked to pubertal development, degenerated germ
cell populations, aging, nutrition, and season of the year in stallions. The
multiplex interplay of germ cells with somatic cells, endocrine and paracrine
factors, growth factors, and signaling molecules contributes to the regulation
of spermatogenesis. A cell-to-cell communication within the testes of these
factors is a fundamental requirement of normal spermatogenesis. A noteworthy
development has been made recently on discovering the effects of different
somatic cells including Leydig, Sertoli, and peritubular myoid cells on
manipulation the fate of spermatogonial stem cells. In this review, we discuss
the self-renewal, differentiation, and apoptotic roles of somatic cells and the
relationship between somatic and germ cells during normal spermatogenesis. We
also summarize the roles of different growth factors, their
paracrine/endocrine/autocrine pathways, and the different cytokines associated
with spermatogenesis. Furthermore, we highlight important matters for further
studies on the regulation of spermatogenesis. This review presents an insight
into the mechanism of spermatogenesis, and helpful in developing better
understanding of the functions of somatic cells, particularly in stallions and
would offer new research goals for developing curative techniques to address
infertility/subfertility in stallions.
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Affiliation(s)
- Muhammad Shakeel
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Clinical Studies, Faculty of
Veterinary and Animal Sciences, Pir Mehr Ali Shah, Arid Agriculture
University, Rawalpindi 44000, Pakistan
| | - Minjung Yoon
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Horse, Companion and Wild
Animal Science, Kyungpook National University, Sangju 37224,
Korea
- Reseach Center for Horse Industry,
Kyungpook National University, Sangju 37224, Korea
- Corresponding author: Minjung Yoon,
Department of Animal Science and Biotechnology, Kyungpook National University,
Sangju 37224, Korea. Tel: +82-54-530-1233, E-mail:
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Brûlé E, Wang Y, Li Y, Lin YF, Zhou X, Ongaro L, Alonso CAI, Buddle ERS, Schneyer AL, Byeon CH, Hinck CS, Mendelev N, Russell JP, Cowan M, Boehm U, Ruf-Zamojski F, Zamojski M, Andoniadou CL, Sealfon SC, Harrison CA, Walton KL, Hinck AP, Bernard DJ. TGFBR3L is an inhibin B co-receptor that regulates female fertility. SCIENCE ADVANCES 2021; 7:eabl4391. [PMID: 34910520 PMCID: PMC8673766 DOI: 10.1126/sciadv.abl4391] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/19/2021] [Indexed: 06/14/2023]
Abstract
Follicle-stimulating hormone (FSH), a key regulator of ovarian function, is often used in infertility treatment. Gonadal inhibins suppress FSH synthesis by pituitary gonadotrope cells. The TGFβ type III receptor, betaglycan, is required for inhibin A suppression of FSH. The inhibin B co-receptor was previously unknown. Here, we report that the gonadotrope-restricted transmembrane protein, TGFBR3L, is the elusive inhibin B co-receptor. TGFBR3L binds inhibin B but not other TGFβ family ligands. TGFBR3L knockdown or overexpression abrogates or confers inhibin B activity in cells. Female Tgfbr3l knockout mice exhibit increased FSH levels, ovarian follicle development, and litter sizes. In contrast, female mice lacking both TGFBR3L and betaglycan are infertile. TGFBR3L’s function and cell-specific expression make it an attractive new target for the regulation of FSH and fertility.
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Affiliation(s)
- Emilie Brûlé
- Department of Anatomy and Cell Biology, McGill University, Montreal, Québec, Canada
| | - Ying Wang
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Yining Li
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Yeu-Farn Lin
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Xiang Zhou
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Luisina Ongaro
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Carlos A. I. Alonso
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | - Evan R. S. Buddle
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
| | | | - Chang-Hyeock Byeon
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Cynthia S. Hinck
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Natalia Mendelev
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - John P. Russell
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, UK
| | - Mitra Cowan
- McGill Integrated Core for Animal Modeling (MICAM), McGill University, Montreal, Québec, Canada
| | - Ulrich Boehm
- Department of Experimental Pharmacology, Center for Molecular Signaling, Saarland University School of Medicine, Homburg, Germany
| | - Frederique Ruf-Zamojski
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Michel Zamojski
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Cynthia L. Andoniadou
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, UK
- Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Stuart C. Sealfon
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Craig A. Harrison
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Kelly L. Walton
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Andrew P. Hinck
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Daniel J. Bernard
- Department of Anatomy and Cell Biology, McGill University, Montreal, Québec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada
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Pool KR, Rickard JP, Pini T, de Graaf SP. Exogenous melatonin advances the ram breeding season and increases testicular function. Sci Rep 2020; 10:9711. [PMID: 32546776 PMCID: PMC7297710 DOI: 10.1038/s41598-020-66594-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/11/2020] [Indexed: 01/19/2023] Open
Abstract
Governed by melatonin, ovine reproductive seasonality limits production outcomes due to periods of decreased reproductive efficiency. Though it is established that slow-release melatonin implants improve out of season reproductive performance in the ewe, the comprehensive effects of exogenous melatonin in the ram remain inconclusive. This study aimed to ultimately clarify the ability of exogenous melatonin to alter ram reproductive function during the non-breeding season and the subsequent breeding season. Hence, we investigated the effect of exogenous melatonin on reproductive endocrinology, semen quality and production, testicular size and libido in Merino and Poll Dorset rams (n = 31, using a subset of 18 rams for analysis of semen production and quality). Melatonin treatment resulted in elevation of melatonin in seminal plasma from 1-8 weeks post-implantation and in blood plasma at 6 weeks post-implantation. The blood plasma testosterone of implanted rams was greater than controls at both 6 weeks post-implantation and during the following breeding season. Implanted rams exhibited increased testicular size and number of sperm per ejaculate from 3-12 weeks post-implantation but did not demonstrate any change in sperm motility or morphology in response to treatment. Compared to their control counterparts, melatonin-treated Poll Dorset rams exhibited a lower percentage of sperm DNA fragmentation during several weeks of the non-breeding season. Though melatonin increased the likelihood of ejaculate collection in Poll Dorset rams (P < 0.05), libido was otherwise unaffected by treatment. Melatonin did not alter seminal plasma concentrations of inhibin A or Anti-Mullerian hormone, however, for the first time in the ram we have shown Anti-Mullerian hormone to be positively correlated with the number of sperm per ejaculate and sperm motility (r = 0.464 and 0.3242 respectively, P < 0.001), and inhibin A to be correlated to the number of sperm per ejaculate (r = 0.1786, P = 0.0135). These results indicate that melatonin is able to both systemically upregulate reproduction and act directly upon testicular function in the ram.
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Affiliation(s)
- K R Pool
- The University of Sydney, Faculty of Science, School of Life and Environmental Sciences, Sydney, NSW, 2006, Australia.
| | - J P Rickard
- The University of Sydney, Faculty of Science, School of Life and Environmental Sciences, Sydney, NSW, 2006, Australia
| | - T Pini
- The University of Sydney, Faculty of Science, School of Life and Environmental Sciences, Sydney, NSW, 2006, Australia
| | - S P de Graaf
- The University of Sydney, Faculty of Science, School of Life and Environmental Sciences, Sydney, NSW, 2006, Australia
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Ball BA, Davolli GM, Esteller-Vico A, Fleming BO, Wynn MAA, Conley AJ. Inhibin-A and Inhibin-B in stallions: Seasonal changes and changes after down-regulation of the hypothalamic-pituitary-gonadal axis. Theriogenology 2018; 123:108-115. [PMID: 30296651 DOI: 10.1016/j.theriogenology.2018.09.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/17/2018] [Accepted: 09/26/2018] [Indexed: 11/26/2022]
Abstract
The biological function of inhibin is mediated by two heterodimers, inhibin-A and inhibin-B. The relative importance of inhibin-A and -B in male reproductive function varies considerably across species with inhibin-B predominating in many species, whereas inhibin-A appears relatively more important in rams. Research reported to date in stallions has examined total or immunoreactive (ir) inhibin which does not distinguish the two heterodimers. Therefore, the objective of this study was to characterize changes in inhibin-A and inhibin-B concentrations in stallions: 1) across season for a period of one year, and 2) after downregulation of the hypothalamic-pituitary-gonadal (HPG) axis. In Study one, serum samples were obtained monthly from five stallions for a period of one year. Serum concentrations of inhibin-A, inhibin-B, testosterone and estrone sulfate were determined by ELISA. In Study two, stallions were treated with the GnRH antagonist, acyline (n = 4; 330 mg/kg acyline IM) or vehicle control (n = 4; vehicle alone) every five days for 50 days. Plasma concentrations of inhibin-A and -B were determined by ELISA at Days 0, 6, 12, 22, 37, 59, 80, 87 and 104 after initiation of acyline treatment. Testis volume was determined by ultrasonography at weekly intervals. In Study 1, both inhibin-A and inhibin-B showed seasonal changes in concentration with highest concentrations in increasing day length and lowest concentrations in short day lengths. Inhibin-B (overall mean 107.8 ± 4.1 pg/mL) was present at 4.7-fold higher concentrations in serum than inhibin-A (overall mean 23.0 ± 0.7 pg/mL). In Study 2, plasma concentrations of inhibin-B but not inhibin-A were significantly downregulated by administration of the GnRH antagonist, acyline. When the HPG axis was downregulated by acyline, testis volume was strongly correlated with inhibin-B (r = 0.73; P < 0.05) but not inhibin-A (r = 0.22; P = 0.20). In summary, inhibin-B appears to be the predominant form of inhibin in the stallion which undergoes seasonal regulation along with other reproductive parameters and is co-regulated with other endocrine parameters of the HPG axis.
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Affiliation(s)
- B A Ball
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA.
| | - G M Davolli
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - A Esteller-Vico
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - B O Fleming
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - M A A Wynn
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - A J Conley
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA
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Han X, Gu L, Xia C, Feng J, Cao X, Du X, Zeng X, Song T. Effect of immunization against GnRH on hypothalamic and testicular function in rams. Theriogenology 2014; 83:642-9. [PMID: 25433833 DOI: 10.1016/j.theriogenology.2014.10.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 10/29/2014] [Accepted: 10/29/2014] [Indexed: 11/15/2022]
Abstract
The objective was to determine effects of active immunization against GnRH on reproductive function in Tibetan rams. Peripubertal Tibetan rams (n = 30) were randomly and equally allocated into three groups: control (no treatment); surgically castrated; or immunized against 100-μg d-Lys6-GnRH-tandem-dimer peptide conjugated to ovalbumin in Specol adjuvant at 24 weeks of age (with a booster 8 weeks later). Blood samples (for antibody titers and hormone concentrations) were collected at 4-week intervals until rams were killed (40 weeks). Immunization triggered a good antibody response in all immunized rams (P < 0.01). Compared with intact controls, anti-GnRH immunization reduced (P < 0.01) serum concentrations of testosterone, inhibin A, LH, and FSH, and it induced testicular atrophy (suppression of spermatogenesis). Androstenone concentrations in fat tissues of GnRH-immunized rams were also rendered nondetectable (P < 0.001). Furthermore, mRNA expressions of GnRH receptor, LH-β, and FSH-β in the pituitary and of LH receptor, FSH receptor, and inhibin α and βA subunits in the testes were decreased in immunized rams compared with intact controls (P < 0.05). This was apparently the first report that active immunization against GnRH-tandem-dimer-ovalbumin conjugate in Specol adjuvant was an effective alternative to surgical castration for Tibetan rams under practical Tibetan plateau conditions.
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Affiliation(s)
- Xingfa Han
- Isotope Research Lab, Sichuan Agricultural University, Ya'an, P.R. China
| | - Longjun Gu
- Isotope Research Lab, Sichuan Agricultural University, Ya'an, P.R. China
| | - Chenyang Xia
- Institute of Animal Science, Tibet Academy of Agricultural and Animal Husbandry Science, Lhasa, P.R. China
| | - Jing Feng
- Institute of Animal Science, Tibet Academy of Agricultural and Animal Husbandry Science, Lhasa, P.R. China
| | - Xiaohan Cao
- Isotope Research Lab, Sichuan Agricultural University, Ya'an, P.R. China
| | - Xiaogang Du
- Isotope Research Lab, Sichuan Agricultural University, Ya'an, P.R. China
| | - Xianyin Zeng
- Isotope Research Lab, Sichuan Agricultural University, Ya'an, P.R. China.
| | - Tianzeng Song
- Institute of Animal Science, Tibet Academy of Agricultural and Animal Husbandry Science, Lhasa, P.R. China.
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Makanji Y, Zhu J, Mishra R, Holmquist C, Wong WPS, Schwartz NB, Mayo KE, Woodruff TK. Inhibin at 90: from discovery to clinical application, a historical review. Endocr Rev 2014; 35:747-94. [PMID: 25051334 PMCID: PMC4167436 DOI: 10.1210/er.2014-1003] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
When it was initially discovered in 1923, inhibin was characterized as a hypophysiotropic hormone that acts on pituitary cells to regulate pituitary hormone secretion. Ninety years later, what we know about inhibin stretches far beyond its well-established capacity to inhibit activin signaling and suppress pituitary FSH production. Inhibin is one of the major reproductive hormones involved in the regulation of folliculogenesis and steroidogenesis. Although the physiological role of inhibin as an activin antagonist in other organ systems is not as well defined as it is in the pituitary-gonadal axis, inhibin also modulates biological processes in other organs through paracrine, autocrine, and/or endocrine mechanisms. Inhibin and components of its signaling pathway are expressed in many organs. Diagnostically, inhibin is used for prenatal screening of Down syndrome as part of the quadruple test and as a biochemical marker in the assessment of ovarian reserve. In this review, we provide a comprehensive summary of our current understanding of the biological role of inhibin, its relationship with activin, its signaling mechanisms, and its potential value as a diagnostic marker for reproductive function and pregnancy-associated conditions.
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Affiliation(s)
- Yogeshwar Makanji
- Department of Obstetrics and Gynecology (Y.M., J.Z., C.H., W.P.S.W., T.K.W.), Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60610; Center for Molecular Innovation and Drug Discovery (R.M., C.H.), Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208; and Department of Molecular Biosciences (N.B.S., K.E.M., T.K.W.), Center for Reproductive Science, Northwestern University, Evanston, Illinois 60208
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Campbell BK, Hernandez-Medrano J, Onions V, Pincott-Allen C, Aljaser F, Fisher J, McNeilly AS, Webb R, Picton HM. Restoration of ovarian function and natural fertility following the cryopreservation and autotransplantation of whole adult sheep ovaries. Hum Reprod 2014; 29:1749-63. [PMID: 24939954 PMCID: PMC4093995 DOI: 10.1093/humrep/deu144] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
STUDY QUESTION Is it possible to restore ovarian function and natural fertility following the cryopreservation and autotransplantation of whole ovaries, complete with vascular pedicle, in adult females from a large monovulatory animal model species (i.e. sheep)? SUMMARY ANSWER Full (100%) restoration of acute ovarian function and high rates of natural fertility (pregnancy rate 64%; live birth rate 29%), with multiple live births, were obtained following whole ovary cryopreservation and autotransplantation (WOCP&TP) of adult sheep ovaries utilizing optimized cryopreservation and post-operative anti-coagulant regimes. WHAT IS KNOWN ALREADY Fertility preservation by WOCP&TP requires successful cryopreservation of both the ovary and its vascular supply. Previous work has indicated detrimental effects of WOCP&TP on the ovarian follicle population. Recent experiments suggest that these deleterious effects can be attributed to an acute loss of vascular patency due to clot formation induced by damage to ovarian arterial endothelial cells. STUDY DESIGN, SIZE, DURATION Study 1 (2010–2011; N = 16) examined the effect of post-thaw perfusion of survival factors (angiogenic, antioxidant, anti-apoptotic; n = 7–8) and treatment with aspirin (pre-operative versus pre- and post-operative (n = 7–9)) on the restoration of ovarian function for 3 months after WOCP&TP. Study 2 (2011–2012; N = 16) examined the effect of cryoprotectant (CPA) perfusion time (10 versus 60 min; n = 16) and pre- and post-operative treatment with aspirin in combination with enoxaparine (Clexane®; n = 8) or eptifibatide (Integrilin®; n = 8) on ovarian function and fertility 11–23 months after WOCP&TP. PARTICIPANTS/MATERIALS, SETTING, METHODS Both studies utilized mature, parous, Greyface ewes aged 3–6 years and weighing 50–75 kg. Restoration of ovarian function was monitored by bi-weekly blood sampling and display of behavioural oestrus. Blood samples were assayed for gonadotrophins, progesterone, anti-Müllerian Hormone and inhibin A. Fertility restoration in Study 2 was quantified by pregnancy rate after a 3 month fertile mating period and was confirmed by ultrasound, hormonal monitoring and live birth. Ovarian function was assessed at sacrifice by ovarian appearance and vascular patency (Doppler ultrasound) and by follicular histology. MAIN RESULTS AND THE ROLE OF CHANCE In Study 1, survival factors were found to have no benefit, but the inclusion of pre-operative aspirin resulted in four ewes showing acute restoration of ovarian function within 3 weeks and a further six ewes showing partial restoration. The addition of post-operative aspirin alone had no clear benefit. In Study 2, combination of aspirin with additional post-operative anti-coagulants resulted in total acute restoration of ovarian function in 14/14 ewes within 3 weeks of WOCP&TP, with 9/14 ewes becoming pregnant and 4/14 giving birth to a total of seven normal lambs. There was no difference between anti-coagulants in terms of restoration of reproductive function and fertility. In contrast, the duration of CPA perfusion was highly significant with a 60 min perfusion resulting in ovaries of normal appearance and function with high rates of primordial follicle survival (70%) and an abundant blood supply, whereas ovaries perfused for 10 min had either resorbed completely and were vestigial (7/14) or were markedly smaller (P < 0.01). It is concluded that both the degree of CPA penetration and the maintenance of post-operative vascular patency are critical determinants of the success of WOCP&TP. LIMITATIONS, REASONS FOR CAUTION Before application of this technology to fertility preservation patients, it will be critical to optimize the CPA perfusion time for different sized human ovaries, determine the optimum period and level of anti-coagulant therapy, and confirm the normality of offspring derived from this procedure. WIDER IMPLICATIONS OF THE FINDINGS This technology holds promise for the preservation of fertility in women. It could also potentially be applied to the cryopreservation of other reproductive or even major organs (kidneys) where there are considerable difficulties in storing donated tissue. STUDY FUNDING/COMPETING INTEREST(S) Funding was received from the Medical Research Council, University of Nottingham. The authors confirm that they have no conflict of interest in relation to this work.
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Affiliation(s)
- B K Campbell
- Division of Child Health Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - J Hernandez-Medrano
- Division of Child Health Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - V Onions
- Division of Child Health Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - C Pincott-Allen
- Division of Child Health Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - F Aljaser
- Division of Child Health Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - J Fisher
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
| | - A S McNeilly
- MRC Centre for Reproductive Health, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - R Webb
- Division of Animal Science, School of Biosciences, University of Nottingham, Nottingham LE12 5RD, UK
| | - H M Picton
- Reproduction and Early Development, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK
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Hedger MP, Winnall WR. Regulation of activin and inhibin in the adult testis and the evidence for functional roles in spermatogenesis and immunoregulation. Mol Cell Endocrinol 2012; 359:30-42. [PMID: 21964464 DOI: 10.1016/j.mce.2011.09.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 09/16/2011] [Accepted: 09/16/2011] [Indexed: 02/03/2023]
Abstract
Activin A provides a unique link between reproduction and immunity, which is especially significant in the adult testis. This cytokine, together with inhibin B and follistatin acting as regulators of activin A activity, is fundamentally involved in the regulation of spermatogenesis and testicular steroidogenesis. However, activin A also has a much broader role in control of inflammation, fibrosis and immunity. In the Sertoli cell, activin A is regulated by signalling pathways that normally regulate stress and inflammation, signalling pathways that intersect with the classical hormonal regulatory pathways mediated by FSH. Modulation of activin A production and activity during spermatogenesis is implicated in the fine control of the cycle of the seminiferous epithelium. The immunoregulatory properties of activin A also suggest that it may be involved in maintaining testicular immune privilege. Consequently, elevated activin A production within the testis during inflammation and infection may contribute to spermatogenic failure, fibrosis and testicular damage.
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Affiliation(s)
- Mark P Hedger
- Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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10
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McNeilly AS. Diagnostic applications for inhibin and activins. Mol Cell Endocrinol 2012; 359:121-5. [PMID: 21741437 DOI: 10.1016/j.mce.2011.06.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 06/15/2011] [Accepted: 06/16/2011] [Indexed: 10/18/2022]
Abstract
Inhibin and activins play major roles as paracrine and autocrine signaling molecules in reproduction and development where the main emphasis has been placed in developing potential diagnostic applications. While a role for activin assays in diagnostics has so far been unfounded, ELISAs specific for the biologically active inhibin A and B dimers, and for free inhibin alpha subunits, alone or in combination have found some specific diagnostic applications. Addition of inhibin A to the triple test for Down syndrome in the second trimester of pregnancy, measurement of total inhibin as a marker of certain forms of ovarian cancer in specific circumstances, and inhibin B for male fertility are useful diagnostics. A review of the evidence so far suggests that other applications for inhibin and activin assays have yet to be confirmed, or translated into reliable tools for clinical practice.
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Affiliation(s)
- Alan S McNeilly
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom.
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11
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Berlinguer F, Gonzalez-Bulnes A, Spezzigu A, Contreras-Solis I, Succu S, McNeilly AS, Naitana S, Leoni GG. Effect of aging on follicular function may be relieved by exogenous gonadotropin treatment in a sheep model. Reproduction 2012; 144:245-55. [PMID: 22685252 DOI: 10.1530/rep-12-0030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The current study investigated hormonal and ovarian changes during physiological reproductive aging in Sarda ewes. In a first experiment, follicular and corpus luteum dynamics were compared during an induced oestrus cycle in aged (12-14 years) and young adult ewes (4-5 years). Oestrus cycle characteristics did not differ between the two experimental groups. However, follicular function during the follicular phase showed significant alterations in aged ewes, as determined by a lack of dominance effect and by lower mean values of circulating oestradiol (E(2)) and inhibin levels, compared with young adult ewes. In a second experiment, differences in follicle growth, hormonal milieu and oocyte quality in response to exogenous FSH administration were assessed in aged and adult ewes. No differences were recorded in ovarian response to FSH treatment between young adult and aged ewes, as evaluated by ultrasonographic data and circulating concentrations of LH, E(2) and inhibin-A. Although the total number of recovered oocytes was similar in the two age groups, the number of good quality oocytes selected for IVM was significantly lower in aged ewes compared with adult ones. Thereafter, no differences were recorded in cleavage rates, total blastocyst output, embryo developmental kinetic and quality between aged and adult groups. In conclusion, this study demonstrated that reproductive aging in sheep is associated with impaired follicle functionality and an increase in the proportion of oocytes showing morphological abnormalities. However interestingly, oocyte developmental competence in vitro and embryo cryotolerance were not affected by the aging process, when only good quality oocytes were chosen.
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Affiliation(s)
- Fiammetta Berlinguer
- Department of Animal Biology, University of Sassari, Via Vienna 2, 07100 Sassari, Italy.
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12
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Young JM, Henderson S, Souza C, Ludlow H, Groome N, McNeilly AS. Activin B is produced early in antral follicular development and suppresses thecal androgen production. Reproduction 2012; 143:637-50. [PMID: 22450673 PMCID: PMC3342735 DOI: 10.1530/rep-11-0327] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Little is known about the role of activin B during folliculogenesis. This study investigated the expression levels of activin/inhibin subunits (βA, βB, and α), steroid enzyme, and gonadotrophin receptors in theca (TC) and granulosa cells (GC) by QPCR and activin A and B and inhibin A protein levels in follicular fluid (FF) of developing sheep follicles during estrus and anestrus. The effect of activin B on androgen production from primary TC cultures in vitro was also assessed. During folliculogenesis, in anestrus and estrus, FF activin B concentrations and thecal and GC activin βB mRNA levels decreased as follicle diameter increased from 1–3 to >6 mm regardless of estrogenic status. Estrogenic preovulatory follicles had reduced concentrations of FF activins B and A, and TC and GCs expressed higher levels of activin βA mRNA at 3–4 mm, and TCs more inhibin α mRNA at >4 mm stages of development compared with nonestrogenic follicles. Activin B decreased androstenedione production from primary TCs in vitro, an effect blocked by inhibin A. Thus, sheep follicles 1–3 mm in diameter contained high FF levels of activin B, which decreased as the follicle size increased, and, like activin A, suppressed thecal androgen production in vitro, an effect blocked by inhibin. Furthermore, the theca of large estrogenic follicles expressed high levels of inhibin α and activin βA mRNA suggesting local thecal derived inhibin A production. This would inhibit the negative effects of thecal activins B and A ensuring maximum androgen production for enhanced estradiol production by the preovulatory follicle(s).
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Affiliation(s)
- J M Young
- MRC Human Reproductive Sciences Unit, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK.
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13
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Young JM, McNeilly AS. Inhibin removes the inhibitory effects of activin on steroid enzyme expression and androgen production by normal ovarian thecal cells. J Mol Endocrinol 2012; 48:49-60. [PMID: 22082494 PMCID: PMC3266103 DOI: 10.1530/jme-11-0134] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Activin and inhibin are important local modulators of theca cell steroidogenesis in the ovary. Using a serum-free primary theca cell culture system, this study investigated the effects of inhibin on theca cell androgen production and expression of steroidogenic enzymes. Androstenedione secretion from theca cells cultured in media containing activin, inhibin and follistatin was assessed by RIA over 144 h. Activin (1-100 ng/ml) suppressed androstenedione production. Inhibin (1-100 ng/ml) blocked the suppressive effects of added activin, but increased androstenedione production when added alone, suggesting it was blocking endogenous activin produced by theca cells. Addition of SB-431542 (activin receptor inhibitor) and follistatin (500 ng/ml) increased androstenedione production, supporting this concept. Infection of theca cells with adenoviruses expressing inhibitory Smad6 or 7 increased androstenedione secretion, confirming that the suppressive effects of activin required activation of the Smad2/3 pathway. Activin decreased the expression levels of steroidogenic acute regulatory protein (STAR), whereas STAR expression was increased by inhibin and SB-431542, alone and in combination. CYP11A was unaffected. The expression of CYP17 encoding 17α-hydroxylase was unaffected by activin but increased by inhibin and SB-431542, and when added in combination the effect was further enhanced. The expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) was significantly decreased by activin, while inhibin alone and in combination with SB-431542 both potently increased the expression of 3β-HSD. In conclusion, activin suppressed theca cell androstenedione production by decreasing the expression of STAR and 3β-HSD. Inhibin and other blockers of activin action reversed this effect, supporting the concept that endogenous thecal activin modulates androgen production in theca cells.
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Affiliation(s)
- J M Young
- MRC Human Reproductive Sciences Unit, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK.
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14
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Bellingham M, McKinnell C, Fowler PA, Amezaga MR, Zhang Z, Rhind SM, Cotinot C, Mandon-Pepin B, Evans NP, Sharpe RM. Foetal and post-natal exposure of sheep to sewage sludge chemicals disrupts sperm production in adulthood in a subset of animals. ACTA ACUST UNITED AC 2011; 35:317-29. [PMID: 22150464 PMCID: PMC3440584 DOI: 10.1111/j.1365-2605.2011.01234.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Exposure to ubiquitous, environmental chemicals (ECs) has been hypothesized as a cause for declining male reproductive health. Understanding the long-term effects of EC exposure on reproductive health in humans requires animal models and exposure to ‘real life’, environmentally relevant, mixtures during development, a life stage of particular sensitivity to ECs. The aim of this study was to evaluate the effects of in utero and post-natal exposure to environmentally relevant levels of ECs, via sewage sludge application to pasture, on the adult male sheep testis. Hormones, liver concentrations of candidate ECs and Sertoli and germ cell numbers in testes of adult rams that were exposed to ECs in sewage sludge in utero, and until weaning via maternal exposure, and post-weaning via grazing pastures fertilized with sewage sludge, were quantified. Evaluated as a single group, exposure to sludge ECs was without significant effect on most parameters. However, a more detailed study revealed that 5 of 12 sludge-exposed rams exhibited major spermatogenic abnormalities. These consisted of major reductions in germ cell numbers per testis or per Sertoli cell and more Sertoli cell-only tubules, when compared with controls, which did not show any such changes. The sludge-related spermatogenic changes in the five affected animals were significantly different from controls (p < 0.001); Sertoli cell number was unaffected. Hormone profiles and liver candidate EC concentrations were not measurably affected by exposure. We conclude that developmental exposure of male sheep to real-world mixtures of ECs can result in major reduction in germ cell numbers, indicative of impaired sperm production, in a proportion of exposed males. The individual-specific effects are presumed to reflect EC effects on a heterogeneous population in which some individuals may be more susceptible to adverse EC effects. Such effects of EC exposure in humans could have adverse consequences for sperm counts and fertility in some exposed males.
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Affiliation(s)
- M Bellingham
- Institute of Biodiversity, Animal Health and Comparative Medicine, School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK.
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15
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Kazutaka S, Winnall WR, Muir JA, Hedger MP. Regulation of Sertoli cell activin A and inhibin B by tumour necrosis factor α and interleukin 1α: interaction with follicle-stimulating hormone/adenosine 3',5'-cyclic phosphate signalling. Mol Cell Endocrinol 2011; 335:195-203. [PMID: 21256182 DOI: 10.1016/j.mce.2011.01.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 01/13/2011] [Accepted: 01/14/2011] [Indexed: 10/18/2022]
Abstract
Regulation of crucial events during spermatogenesis involves dynamic changes in cytokine production and interactions across the cycle of the seminiferous epithelium. Regulation of activin A and inhibin B production by the inflammatory cytokines, tumour necrosis factor α (TNFα) and interleukin 1α (IL1α), alone and in conjunction with FSH or a cAMP analogue (dibutyryl cAMP), was examined in cultures of Sertoli cells from 20-day old rats. Both TNFα and IL1α stimulated activin A secretion and expression of its subunit (β(A)) mRNA, and suppressed inhibin B secretion and expression of its subunit (α and β(B)) mRNAs. The actions of TNFα and IL1α were opposed by FSH and dibutyryl cAMP. Both cytokines inhibited FSH/dibutyryl cAMP-stimulated inhibin B secretion and mRNA expression as well as stem cell factor mRNA expression. Both cytokines also inhibited FSH-induced cAMP production, and reduced baseline FSH receptor mRNA expression. These data highlight the reciprocal relationship that exists between FSH/cAMP signalling and inflammatory cytokine signalling pathways in the control of Sertoli cell function, and production of activin A/inhibin B in particular. It is anticipated that these interactions play important roles in the fine control of events during the cycle of the seminiferous epithelium and in the inhibition of spermatogenesis during inflammation.
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Affiliation(s)
- Saito Kazutaka
- Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia
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16
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Scaramuzzi RJ, Baird DT, Campbell BK, Driancourt MA, Dupont J, Fortune JE, Gilchrist RB, Martin GB, McNatty KP, McNeilly AS, Monget P, Monniaux D, Viñoles C, Webb R. Regulation of folliculogenesis and the determination of ovulation rate in ruminants. Reprod Fertil Dev 2011; 23:444-67. [DOI: 10.1071/rd09161] [Citation(s) in RCA: 185] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2009] [Accepted: 10/05/2010] [Indexed: 11/23/2022] Open
Abstract
The paper presents an update of our 1993 model of ovarian follicular development in ruminants, based on knowledge gained from the past 15 years of research. The model addresses the sequence of events from follicular formation in fetal life, through the successive waves of follicular growth and atresia, culminating with the emergence of ovulatory follicles during reproductive cycles. The original concept of five developmental classes of follicles, defined primarily by their responses to gonadotrophins, is retained: primordial, committed, gonadotrophin-responsive, gonadotrophin-dependent and ovulatory follicles. The updated model has more extensive integration of the morphological, molecular and cellular events during folliculogenesis with systemic events in the whole animal. It also incorporates knowledge on factors that influence oocyte quality and the critical roles of the oocyte in regulating follicular development and ovulation rate. The original hypothetical mechanisms determining ovulation rate are retained but with some refinements; the enhanced viability of gonadotrophin-dependent follicles and increases in the number of gonadotrophin-responsive follicles by increases in the throughput of follicles to this stage of growth. Finally, we reexamine how these two mechanisms, which are thought not to be mutually exclusive, appear to account for most of the known genetic and environmental effects on ovulation rate.
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17
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George JW, Dille EA, Heckert LL. Current concepts of follicle-stimulating hormone receptor gene regulation. Biol Reprod 2011; 84:7-17. [PMID: 20739665 PMCID: PMC4480823 DOI: 10.1095/biolreprod.110.085043] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 05/04/2010] [Accepted: 08/16/2010] [Indexed: 12/25/2022] Open
Abstract
Follicle-stimulating hormone (FSH), a pituitary glycoprotein hormone, is an integral component of the endocrine axis that regulates gonadal function and fertility. To transmit its signal, FSH must bind to its receptor (FSHR) located on Sertoli cells of the testis and granulosa cells of the ovary. Thus, both the magnitude and the target of hormone response are controlled by mechanisms that determine FSHR levels and cell-specific expression, which are supported by transcription of its gene. The present review examines the status of FSHR/Fshr gene regulation, emphasizing the importance of distal sequences in FSHR/Fshr transcription, new insights gained from the influx of genomics data and bioinformatics, and emerging trends that offer direction in deciphering the FSHR/Fshr regulatory landscape.
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Affiliation(s)
- Jitu W. George
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas
| | - Elizabeth A. Dille
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas
| | - Leslie L. Heckert
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas
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18
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Nicol L, Bishop SC, Pong-Wong R, Bendixen C, Holm LE, Rhind SM, McNeilly AS. Homozygosity for a single base-pair mutation in the oocyte-specific GDF9 gene results in sterility in Thoka sheep. Reproduction 2009; 138:921-33. [DOI: 10.1530/rep-09-0193] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The control of fecundity is critical in determining mammalian offspring survival. It is regulated principally by the ovulation rate, so that primates and large farm species commonly have a single offspring. Previously, several mutations have been identified in sheep which increase the naturally low ovulation rate; although in some cases homozygous ewes are infertile. In the present study we present a detailed characterization of a novel mutation in growth differentiation factor 9 (GDF9), found in Icelandic Thoka sheep. This mutation is a single base change (A1279C) resulting in a nonconservative amino acid change (S109R) in the C-terminus of the mature GDF9 protein, which is normally expressed in oocytes at all stages of development. Genotyping all animals for which reproductive records were available confirmed this mutation to be associated with increased fecundity in heterozygous ewes and infertility in homozygotes. Analysis of homozygote ovarian morphology and a number of genes normally activated in growing follicles showed that GDF9 was not involved in oocyte activation, but in subsequent development of the follicle. This study highlights the importance of oocyte factors in regulating fertility and provides new information for structural analysis and investigation of the potentially important sites of dimerization or translational modifications required to produce biologically active GDF9. It also provides the basis for the utilization of these animals to enhance sheep production.
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19
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Voge JL, Parker JB, Wheaton JE. Effects of immunization against alpha-inhibin using two adjuvants on daily sperm production and hormone concentrations in ram lambs. Domest Anim Endocrinol 2009; 37:206-13. [PMID: 19646838 DOI: 10.1016/j.domaniend.2009.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 05/27/2009] [Accepted: 05/28/2009] [Indexed: 11/24/2022]
Abstract
Twenty-five ram lambs were immunized against alpha-inhibin peptide emulsified in Freund's adjuvant (FRA), Emulsigen (EML) containing an oligodeoxynucleotide as an immunostimulant, or adjuvant without alpha-inhibin antigen (control). Four immunizations were administered during an 85-d period, after which testes were obtained for determination of daily sperm production (DSP) and histological evaluation. alpha-Inhibin antibody (Ab) titers were 70-fold greater in lambs treated with FRA than in EML-treated ram lambs. alpha-Inhibin immunization had no effect on testes weight or on plasma concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. Mean DSP/g tended (P=0.1) to be greater in alpha-inhibin-immunized (EML=17.6x10(6); FRA=15.8x10(6)) ram lambs than in control animals (14.4x10(6)). One of the 8 control ram lambs had an elevated DSP/g, which was a statistical outlier. Without data from this lamb, DSP/g was increased (P<0.01) in alpha-inhibin-immunized ram lambs by 28% over controls. No association was found between the titer of alpha-inhibin Ab developed and DSP/g. Histologically, the percentage of testicular area occupied by seminiferous tubules differed (P=0.01) by treatment and was greatest (82%) in EML-treated ram alpha-inhibin-immunized lambs and lowest (74%) in control animals. Percentage tubular area and DSP/g were correlated (r=0.57, P=0.003). Findings show that (1) the extent of the increase in DSP/g is not dependent on the titer of alpha-inhibin Ab; (2) the increase in DSP/g is achieved through an increase in the mass of seminiferous tubules; and (3) FRA elicits a greater alpha-inhibin Ab titer than EML containing an oligodeoxynucleotide.
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Affiliation(s)
- J L Voge
- Department of Animal Science, University of Minnesota, St. Paul, MN 55108, USA
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20
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Onions VJ, Webb R, McNeilly AS, Campbell BK. Ovarian endocrine profile and long-term vascular patency following heterotopic autotransplantation of cryopreserved whole ovine ovaries. Hum Reprod 2009; 24:2845-55. [PMID: 19640895 DOI: 10.1093/humrep/dep274] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND This study examined the ability of cryopreserved whole ovine ovaries to resume function in vivo following autotransplantation. METHODS Swaledale ewes had their left ovaries removed and either perfused but not cryopreserved (n = 4; control), or perfused and cryopreserved (n = 8; cryopreserved) before autotransplantation sub-cutaneously to the neck by microvascular anastomosis. Right ovaries were removed and fixed as non-grafted controls. Weekly jugular venous blood samples were analysed for plasma FSH, LH, inhibin A and progesterone levels, grafts were scanned transdermally and oestrus was detected. Vascular patency was assessed post-mortem and follicle populations were measured in recovered tissue. RESULTS Immediate vascular patency was achieved in all ewes and maintained in 7/8 cryopreserved and 3/4 control grafts. Functional corpora lutea were identified in three ewes (one control; two cryopreserved) 18-25 weeks after grafting. Inhibin A levels indicated resumption of follicular development in four cryopreserved and one control ewes, however, castrate gonadotrophin levels persisted in five cryopreserved and two control ewes. Primordial follicle density was reduced following grafting in both cryopreserved and non-frozen ovaries (P < 0.001). CONCLUSIONS In conclusion, these results demonstrate successful partial restoration of ovarian function following cryopreservation of the whole ovary and vascular pedicle in a large monovulatory species. The inability to restore full ovarian function was related to loss of primordial follicles rather than vascular patency in both frozen and fresh tissue, suggesting that factors associated with cannulation and perfusion may contribute to this depletion. Further work is therefore needed to elucidate these factors before the procedure could be considered a viable option for fertility preservation.
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Affiliation(s)
- V J Onions
- Division of Animal Sciences, School of Biosciences, University of Nottingham, Loughborough, Leicestershire LE12 5RD, UK.
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21
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SHENG X, ZHANG H, ZHANG W, SONG M, ZHANG M, LI B, WENG Q, WATANABE G, TAYA K. Seasonal Changes in Spermatogenesis and Immunolocalization of Inhibin/Activin Subunits in the Wild Male Ground Squirrel ( Citellus dauricus Brandt). J Reprod Dev 2008; 54:460-4. [DOI: 10.1262/jrd.20032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Xia SHENG
- College of Biological Science and Technology, Beijing Forestry University
| | - Haolin ZHANG
- College of Biological Science and Technology, Beijing Forestry University
| | - Wei ZHANG
- College of Biological Science and Technology, Beijing Forestry University
| | - Moshi SONG
- College of Biological Science and Technology, Beijing Forestry University
| | - Mengyuan ZHANG
- College of Biological Science and Technology, Beijing Forestry University
| | - Ben LI
- College of Biological Science and Technology, Beijing Forestry University
| | - Qiang WENG
- College of Biological Science and Technology, Beijing Forestry University
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
| | - Gen WATANABE
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
- Department of Basic Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Kazuyoshi TAYA
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
- Department of Basic Science, United Graduate School of Veterinary Sciences, Gifu University
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22
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Voge JL, Wheaton JE. Effects of immunization against two inhibin antigens on daily sperm production and hormone concentrations in ram lambs1. J Anim Sci 2007; 85:3249-55. [PMID: 17878277 DOI: 10.2527/jas.2007-0506] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The gonadal hormone inhibin regulates daily sperm production (DSP) indirectly through negative feedback control of FSH secretion and may also affect DSP via direct actions within the testis. Studies attempting to increase DSP through the immunization against inhibin have yielded equivocal results. The current study compared 2 inhibin antigens for effects on DSP and hormone secretion. Hampshire ram lambs (BW = 42 +/- 2 kg; age = 113 +/- 3 d) were assigned randomly to 3 groups: 1) control (n = 4); 2) alpha-peptide conjugate (PTC, n = 6); and 3) alpha-subunit (SUB, n = 6). Antigen PTC consisted of an alpha-inhibin, N-terminal, 25-amino acid peptide conjugated to ovalbumin. Antigen SUB was the complete inhibin alpha-subunit. Lambs were immunized on d 0 (June 19, 2006), 18, 38, and 63. Body weight was recorded on immunization days and scrotal circumference on d 63. Blood samples were collected on d 0, 7, 14, 18, 28, 35, 38, 49, 56, 63, and 70. Rams were slaughtered on d 71. Testes were weighed, and parenchyma was obtained for DSP determination. Plasma alpha-inhibin antibody titer and LH, FSH, and testosterone concentrations were measured. alpha-Inhibin antibody titer was first detectable on d 14 in both PTC- and SUB-immunized ram lambs and generally increased thereafter. Mean DSP per gram of testis (DSP/g) was increased (P < 0.01) 26% in PTC- and SUB-immunized ram lambs over that in control ram lambs. Total DSP per ram lamb and testes weight did not differ among the 3 treatment groups. Variation in DSP per ram lamb and testes weight were greater (P = 0.05) in PTC- and SUB-immunized ram lambs than in control ram lambs. Plasma FSH concentrations were similar in PTC- and SUB-immunized ram lambs. Immunization against either alpha-inhibin antigen did not alter LH, testosterone, BW, or scrotal circumference. Findings indicate that 1) the 2 alpha-inhibin antigens increase DSP/g to similar extents; 2) alpha-inhibin antibody may act at least in part through an intratesticular mechanism because DSP/g was increased in some animals without concomitant increases in FSH; and 3) immunization against alpha-inhibin may affect testes weight by actions independent of those that regulate DSP/g.
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Affiliation(s)
- J L Voge
- Department of Animal Science, University of Minnesota, St. Paul 55108-6014, USA
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23
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Oatley JM, Tibary A, de Avila DM, Wheaton JE, McLean DJ, Reeves JJ. Changes in spermatogenesis and endocrine function in the ram testis due to irradiation and active immunization against luteinizing hormone-releasing hormone. J Anim Sci 2007; 83:604-12. [PMID: 15705757 DOI: 10.2527/2005.833604x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Spermatogonial stem cell transplantation is a technique that has potential in livestock to enhance genetic gain and generate transgenic offspring through the male germ line. A means for depletion of endogenous germ cells in a recipient's seminiferous tubules is necessary for this technology to be applied. The objectives of this study were to evaluate several methods for depletion of endogenous germ cells in the testes of adult rams and to evaluate ultrasound-guided injections into the rete testes as a means for infusing a suspension into the seminiferous tubules. Sixteen adult rams were randomly divided into 4 treatment groups (n = 4 per group). Treatments consisted of active immunization against LHRH (IMM), localized testicular irradiation (IR), LHRH immunization + irradiation (IMM+IR), and untreated control. Serial bleedings were conducted pretreatment and monthly after treatment for 4 mo, at which time all rams were castrated. Both IMM and IMM+IR rams received exogenous gonadotropin in the form of Perganol weekly for 8 wk before castration to bypass the immunization. All rams also received an ultrasound-guided injection of PBS containing 0.4% trypan blue into the rete testis of one testicle before castration. Rams receiving IMM and IMM+IR treatments had higher (P < 0.05) average percentages of seminiferous tubule cross sections with depleted germ cells compared with controls. Serum testosterone was decreased (P < 0.05) in IMM and IMM+IR rams 1 mo after treatment and throughout the remainder of the study compared with controls and IR rams, which were not different from each other. Serum inhibin concentration was unchanged in all rams following treatment indicating that Sertoli cell function was unaltered. A greater (P < 0.05) average percentage of the total testicular area could be filled with the trypan blue solution by rete testis injection in IMM and IMM+IR rams. These data demonstrate the depletion of endogenous germ cells in adult ram testes without alteration of Sertoli cell viability and function that have potential as methods for preparing recipient animals for germ cell transplantation.
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Affiliation(s)
- J M Oatley
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman 99164, USA.
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24
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Ohnuma K, Kaneko H, Noguchi J, Kikuchi K, Ozawa M, Hasegawa Y. Production of inhibin A and inhibin B in boars: changes in testicular and circulating levels of dimeric inhibins and characterization of inhibin forms during testis growth. Domest Anim Endocrinol 2007; 33:410-21. [PMID: 17010559 DOI: 10.1016/j.domaniend.2006.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 08/08/2006] [Accepted: 08/17/2006] [Indexed: 10/24/2022]
Abstract
We investigated the production of inhibin in boars from the infantile to pubertal periods by: (1) measurement of testicular and circulating levels of inhibin, (2) characterization of inhibin forms and (3) localization of inhibin alpha subunits in the testis. Total inhibin levels in the testis increased until 8 weeks of age but then declined to much lower values at 15 weeks. Testicular inhibin A and inhibin B were high until 8 weeks. Circulating levels of total inhibin and inhibin A were also high until 8 weeks, then declined from 10 weeks; inhibin B was not detected, because of low sensitivity of the inhibin B assay. Analyses of inhibin A and inhibin B levels in the eluted fractions obtained from testes after immunoaffinity chromatography and SDS-PAGE showed the presence of a peak of approximately 45 kDa until 10 weeks of age. As the boars aged, the levels of inhibin A and inhibin B increased in the molecular weight region of 29-31 kDa. The fractions corresponding to 29 and 30 kDa suppressed FSH release from rat pituitary cells, but the 45 kDa fraction had no FSH-suppressing activity. Total amounts of inhibin A isolated from the SDS gels were similar to those of inhibin B until 10 weeks of age, but were three times higher than those of inhibin B between 15 and 25 weeks. Further fractionation by reverse phase high-performance liquid chromatography revealed that the 29-31 kDa immunoreactive material was composed of mature forms of inhibin A and inhibin B, in addition to a 26 kDa alpha monomer. Immunohistochemistry indicated that positive immunostaining for the alpha subunits was observed in Sertoli cells from the infantile to pubertal periods. Elongated spermatids also showed positive signals at age 25 weeks. These results clearly indicated that: (1) the boar testis has the ability to produce inhibin A and inhibin B during the infantile period but inhibin A is the predominant form towards puberty and (2) the molecular weight forms of inhibin and the sites of production of inhibin change with testicular development.
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Affiliation(s)
- Katsuhiko Ohnuma
- Reproductive Biology Research Unit (Kannondai), National Institute of Agrobiological Science, Tsukuba, Ibaraki 305-8602, Japan
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Veiga-Lopez A, Dominguez V, Souza CJH, Garcia-Garcia RM, Ariznavarreta C, Tresguerres JAF, McNeilly AS, Gonzalez-Bulnes A. Features of follicle-stimulating hormone-stimulated follicles in a sheep model: keys to elucidate embryo failure in assisted reproductive technique cycles. Fertil Steril 2007; 89:1328-37. [PMID: 17604028 DOI: 10.1016/j.fertnstert.2007.02.034] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 02/21/2007] [Accepted: 02/21/2007] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the individual functionality of gonadotropin-stimulated preovulatory follicles, for understanding embryo failure in assisted reproductive technique cycles, in a sheep model. DESIGN Observational, model study. SETTING Public research unit. ANIMAL(S) Fifteen adult Manchega ewes. INTERVENTION(S) Synchronization of the estrous cycle with intravaginal progestagens and ovarian stimulation with FSH; evaluation of reproductive activity, plasma sampling, ovarian ultrasonography, and ovariectomies. MAIN OUTCOME MEASURE(S) Determination of estrus behavior, plasma and intrafollicular concentrations of E(2) and inhibin A, number and size of ovarian follicles, and developmental competence of oocytes. RESULT(S) These results support the usefulness of serial measurements of plasma inhibin A for assessment of follicular growth during the FSH treatment, rather than of E(2) assays commonly used. Functionality of FSH-stimulated preovulatory follicles is clearly disturbed, as confirmed by a negative correlation between follicular size and intrafollicular concentrations of inhibin A and E(2) in preovulatory follicles after individual dissection; moreover, the ability of their oocytes to resume meiosis was diminished. CONCLUSION(S) Functionality of follicles in controlled ovarian stimulation (COS), and developmental competence of their oocytes, is disturbed by the high doses of gonadotropin supplied and finally determined by follicular sizes at starting FSH treatment.
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Affiliation(s)
- Almudena Veiga-Lopez
- Departamento de Reproduccion Animal, Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria, Madrid, Spain.
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26
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Makanji Y, Harrison CA, Stanton PG, Krishna R, Robertson DM. Inhibin A and B in vitro bioactivities are modified by their degree of glycosylation and their affinities to betaglycan. Endocrinology 2007; 148:2309-16. [PMID: 17272393 DOI: 10.1210/en.2006-1612] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Inhibin A and B, important regulators of normal function in tissues of the reproductive axis, are glycosylated at either Asn(268) or Asn(268) and Asn(302) in the alpha-subunit to produce 31- and 34-kDa isoforms, respectively. In this study, glycosylated isoforms of recombinant human inhibin A and B were purified from conditioned medium using immunoaffinity chromatography and reversed-phase HPLC. The masses of the purified inhibin preparations were determined by several inhibin immunoassays, and their in vitro bioactivities were based on suppression of FSH release by rat pituitary cells in culture. Based on a ratio of in vitro bioactivity to immunoactivity (B:I ratio), the monoglycosylated 31-kDa inhibin A was 5-fold more potent than the diglycosylated 34-kDa inhibin A (B:I ratio, 1.22 +/- 0.15 vs. 0.24 +/- 0.05; P < 0.001, respectively). The 31-kDa inhibin B was significantly (P < 0.001) more potent (1.75 +/- 0.29) than the 34-kDa form (1.08 +/- 0.20). Because inhibin biological activity is dependent upon interactions with the coreceptor betaglycan, the effect of inhibin glycosylation on betaglycan binding was assessed. Analogous to the pattern of in vitro bioactivity, 31-kDa inhibin A was 12-fold more active (IC(50), 0.68 nM) than the 34-kDa isoform (IC(50), 8.2 nM) at displacing [(125)I]inhibin A from COS7 cells expressing betaglycan. However, the 1.6-fold difference in bioactivity of the inhibin B isoforms was not matched by differences in their affinities for betaglycan. It is concluded that glycosylation of Asn(302) of the alpha-subunit of inhibin A and B results in a decrease in bioactivity, and the effect on inhibin A, at least, is explained by its reduced affinity to betaglycan.
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Affiliation(s)
- Yogeshwar Makanji
- Prince Henry's Institute of Medical Research, Monash University, PO Box 5152, Clayton, Victoria 3168, Australia
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27
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KANEKO H, HASEGAWA Y. Application of time-resolved fluorometry to immunoassays for bovine reproductive hormones. Anim Sci J 2007. [DOI: 10.1111/j.1740-0929.2006.00398.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Gonzalez Añover P, Gonzalez-Bulnes A, Veiga-Lopez A, Garcia-Garcia RM, McNeilly AS, Encinas T. Effects of growth hormone and gonadotrophin releasing hormone antagonists on ovarian follicle growth in sheep. J Vet Pharmacol Ther 2006; 29:373-7. [PMID: 16958781 DOI: 10.1111/j.1365-2885.2006.00756.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Our objective was to determine the effects of the administration of growth hormone (GH) alone or plus teverelix, a gonadotrophin releasing hormone antagonist (GnRHa), on follicle development in sheep. Ewes were treated daily for 6 days by the intramuscular route with 15 mg of GH alone (GH group; n = 6) or combined with two subcutaneous doses of GnRHa (1.5 mg) on days 0 and 3 of GH treatment (GH/GnRHa group; n = 6); the control group (n = 6) received similar treatment with saline solution. Plasma follicle stimulating hormone levels were significantly lower in the GH/GnRHa group than in the control (P < 0.001) and GH groups (P < 0.05). The number of follicles > or =2 mm increased to reach significant differences with control (18.7 +/- 0.6) on day 4 in GH/GnRHa group (22.7 +/- 0.5, P < 0.001) and on day 5 in GH group (20.3 +/- 0.4 vs. 17.0 +/- 0.6, P < 0.05). These results indicate that GH and GnRHa may be useful for increasing the number of gonadotrophin-responsive follicles in the ovary. However, follicle function could be affected as both GH and GH/GnRHa groups showed lower plasma inhibin A concentrations than control sheep (90-110 pg/mL vs. 170-185 pg/mL, P < 0.005).
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Affiliation(s)
- P Gonzalez Añover
- Cátedra de Farmacología, Facultad de Veterinaria, UCM, Madrid, Spain
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29
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Weng Q, Medan MS, Xu M, Tsubota T, Watanabe G, Taya K. Seasonal changes in immunolocalization of inhibin/activin subunits and testicular activity in wild male raccoon dogs (Nyctereutes procyonoides). J Reprod Dev 2006; 52:503-10. [PMID: 16702758 DOI: 10.1262/jrd.18011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thirty-four pairs of testes from wild adult raccoon dogs (Nyctereutes procyonoides) were obtained between September 2000 and May 2003. The cellular localization of the inhibin alpha and inhibin/activin (betaA and betaB) subunits in wild raccoon dog testes was investigated. The testicular weight and size and seminiferous tubule diameters were measured. There were marked seasonal variations in testicular weight and size and seminiferous tubule diameters, with values relatively low in September and high in March. Spermatogonia and primary spermatocytes were observed in September, and spermatogonia, spermatocytes, and round spermatids were present in January. All types of spermatogenic cells, including mature spermatozoa, were found in March, indicating that the breeding season is around March in Japan. Thereafter, spermatogonia and degenerating spermatocytes were observed in April. The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA and inhibin/activin betaB. The inhibin alpha and inhibin/activin (betaA and betaB) subunits were only expressed in Leydig cells in September. On the other hand, the inhibin alpha, betaA, and betaB subunits were observed in Leydig cells and Sertoli cells, but not in germ cells, in March. These results suggest that the testes of wild raccoon dogs have the ability to synthesize inhibins, and the cellular localization of inhibin/activin subunits showed season-related changes in the breeding and non-breeding seasons.
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Affiliation(s)
- Qiang Weng
- Faculty of Biological Science and Technology, Beijing Forestry University, China
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30
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Kaneko H, Matsuzaki M, Noguchi J, Kikuchi K, Ohnuma K, Ozawa M. Changes in Circulating and Testicular Levels of Inhibin A and B During Postnatal Development in Bulls. J Reprod Dev 2006; 52:741-9. [PMID: 16946582 DOI: 10.1262/jrd.18060] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated testicular and circulating levels of dimeric inhibins in Holstein bulls from the infantile to postpubertal periods (5 to 50 weeks of age) and examined the relationship between the profiles of circulating dimeric inhibins and FSH. Concentrations of total inhibin and inhibin B in the testis were highest at 4 to 5 weeks of age but decreased gradually as the bulls aged. Testicular inhibin A levels showed a gradual decline to a nadir at 15 to 26 weeks of age, but by 39 weeks, they were high again. The contents of total inhibin, inhibin A, and inhibin B per testis generally increased with age. Fractionation of testicular homogenates obtained from 15-week-old bulls by a combination of immunoaffinity chromatography and SDS-PAGE confirmed the presence of two major molecular weight forms (32 and 45 kDa) of dimeric inhibins in the testes. Circulating levels of total inhibin and inhibin A showed a significant increase in bulls at around 10 to 14 weeks of age compared to the levels between 5 and 7 weeks of age but decreased thereafter. However, immunoreactivity for inhibin B was not detected in the peripheral circulation, probably because of low sensitivity of the inhibin B assays. The concentrations of plasma FSH were high at 5 weeks of age but declined to lower levels between 11 and 40 weeks, and then increased from 41 weeks onward. There was no significant correlation between the plasma levels of FSH and inhibin A or total inhibin. The results clearly indicate that the bull testis produces inhibin A and B and secretes at least inhibin A into the circulation during postnatal development. However, the profile of circulating FSH in bulls shows no reciprocal relationship with the inhibin A or total inhibin profile during the postnatal period.
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Affiliation(s)
- Hiroyuki Kaneko
- Reproductive Biology Research Unit (Kannondai), Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
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31
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Lopez-Alonso C, Encinas T, Veiga-Lopez A, Garcia-Garcia RM, Cocero MJ, Ros JM, McNeilly AS, Gonzalez-Bulnes A. Follicular growth, endocrine response and embryo yields in sheep superovulated with FSH after pretreatment with a single short-acting dose of GnRH antagonist. Theriogenology 2005; 64:1833-43. [PMID: 15939464 DOI: 10.1016/j.theriogenology.2005.04.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 04/08/2005] [Accepted: 04/19/2005] [Indexed: 11/30/2022]
Abstract
The objective of this study was to characterize follicular development, onset of oestrus and preovulatory LH surge, and in vivo embryo yields of sheep superovulated after treatment with a single dose of 1.5mg of GnRH antagonist (GnRHa). At first FSH dose, ewes treated with GnRH antagonist (n=12) showed a higher number of gonadotrophin-responsive follicles, 2-3mm, than control ewes (n=9, 13.5+/-3.8 versus 5.3+/-0.3, P<0.05). Administration of FSH increased the number of >or=4mm follicles at sponge removal in both groups (19.3+/-3.8, P<0.0005 for treated ewes and 12.7+/-5.4, P<0.01 for controls). Thereafter, a 25% of the GnRHa-treated sheep did not show oestrous behaviour whilst none control sheep failed (P=0.06). The preovulatory LH surge was detected in an 88.9% of control ewes and 66.7% of GnRHa-treated sheep. A 77.8% of control females showed ovulation with a mean of 9.6+/-0.9 CL and 3.3+/-0.7 viable embryos, while ewes treated with GnRHa and showing an LH surge exhibited a bimodal distribution of response; 50% showed no ovulatory response and 50% superovulated with a mean of 12.2+/-1.1 CL and 7.3+/-1.1 viable embryos. In conclusion, a single dose of GnRHa enhances the number of gonadotrophin-dependent follicles able to grow to preovulatory sizes in response to an FSH supply. However, LH secretion may be altered in some females, which can affect the preovulatory LH surge and/or can weak the terminal maturation of ovulatory follicles.
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Affiliation(s)
- C Lopez-Alonso
- Catedra de Farmacologia, Facultad de Veterinaria, UCM, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
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Paul C, Rhind SM, Kyle CE, Scott H, McKinnell C, Sharpe RM. Cellular and hormonal disruption of fetal testis development in sheep reared on pasture treated with sewage sludge. ENVIRONMENTAL HEALTH PERSPECTIVES 2005; 113:1580-7. [PMID: 16263515 PMCID: PMC1310922 DOI: 10.1289/ehp.8028] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The purpose of this study was to evaluate whether experimental exposure of pregnant sheep to a mixture of environmental chemicals added to pasture as sewage sludge (n = 9 treated animals) exerted effects on fetal testis development or function; application of sewage sludge was undertaken so as to maximize exposure of the ewes to its contents. Control ewes (n = 9) were reared on pasture treated with an equivalent amount of inorganic nitrogenous fertilizer. Treatment had no effect on body weight of ewes, but it reduced body weight by 12-15% in male (n = 12) and female (n = 8) fetuses on gestation day 110. In treated male fetuses (n = 11), testis weight was significantly reduced (32%), as were the numbers of Sertoli cells (34% reduction), Leydig cells (37% reduction), and gonocytes (44% reduction), compared with control fetuses (n = 8). Fetal blood levels of testosterone and inhibin A were also reduced (36% and 38%, respectively) in treated compared with control fetuses, whereas blood levels of luteinizing hormone and follicle-stimulating hormone were unchanged. Based on immunoexpression of anti-Müllerian hormone, cytochrome P450 side chain cleavage enzyme, and Leydig cell cytoplasmic volume, we conclude that the hormone changes in treated male fetuses probably result from the reduction in somatic cell numbers. This reduction could result from fetal growth restriction in male fetuses and/or from the lowered testosterone action; reduced immunoexpression of alpha-smooth muscle actin in peritubular cells and of androgen receptor in testes of treated animals supports the latter possibility. These findings indicate that exposure of the developing male sheep fetus to real-world mixtures of environmental chemicals can result in major attenuation of testicular development and hormonal function, which may have consequences in adulthood.
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Affiliation(s)
- Catriona Paul
- MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
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Abstract
Advances in our understanding of the complexity of GnRH actions at the pituitary and the various mechanisms involved in mediating differential LH and FSH biosynthesis and secretion at the gonadotrope, are continually emerging. In this review, we summarise recent studies pertaining to GnRH and GnRH receptor phylogeny, the divergent signalling and trafficking pathways initiated and utilised by GnRH and its receptor, and the pathways that mediate gonadotropin secretion from the gonadotrope.
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Affiliation(s)
- Adam J Pawson
- Human Reproductive Sciences Unit, Medical Research Council, The University of Edinburgh Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
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34
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Lopez-Alonso C, Encinas T, Garcia-Garcia RM, Veiga-Lopez A, Ros JM, McNeilly AS, Gonzalez-Bulnes A. Administration of single short-acting doses of GnRH antagonist modifies pituitary and follicular function in sheep. Domest Anim Endocrinol 2005; 29:476-87. [PMID: 16153498 DOI: 10.1016/j.domaniend.2005.02.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 02/14/2005] [Accepted: 02/22/2005] [Indexed: 11/23/2022]
Abstract
Current study determined the effect of two different single subcutaneous doses (1.5 and 3 mg) of GnRH antagonist (GnRHa) on pituitary and follicular function in non-lactating cyclic ewes. Both doses abolished the pulsatile secretion of luteinizing hormone (LH) for at least 3 days and decreased mean LH concentration during 6 days (0.64 +/- 0.09 for control and 0.54 +/- 0.05, P < 0.005, and 0.46 +/- 0.02, P < 0.00001, for 1.5 and 3 mg, respectively). Supply of GnRHa decreased the number of large dominant follicles, so the total number of smaller follicles, 2-3 mm in size, increased in both treated groups from day 0, reaching its maximum at day 2 in ewes treated with 1.5 mg (19.83+/-1.05 versus 5.83 +/- 0.50 in the control, P < 0.005) and at day 4 in sheep treated with 3mg (18.67 +/- 0.65 versus 5.50 +/- 0.65 in the control, P < 0.0001). However, the analysis of follicular function in terms of inhibin A indicated a possible effect of the higher dose of GnRHa on follicular function. The pattern of inhibin secretion in the group treated with 3mg of GnRHa decreased after the first 48 h, reaching its lowest value on day 4.5 (182.59 +/- 3.75 to 140.28 +/- 9.91 pg/ml, P < 0.05) concentration significant lower than control sheep (171.93 +/- 6.21 pg/ml, P +/- 0.01) or treated with 1.5 mg (168.04 +/- 7.16 pg/ml, P+ /- 0.05). Hence, the use of 1.5 mg would be more suitable to induce the presence of a high number of follicles able to grow to preovulatory sizes.
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Affiliation(s)
- C Lopez-Alonso
- Catedra de Farmacologia, Facultad de Veterinaria, UCM, Madrid, Spain
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35
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Gonzalez-Bulnes A, Lopez-Sebastian A, Garcia-Garcia RM, Veiga-Lopez A, Souza CJH, McNeilly AS. Restoration of endocrine and ovarian function after stopping GnRH antagonist treatment in goats. Theriogenology 2005; 63:83-91. [PMID: 15589275 DOI: 10.1016/j.theriogenology.2004.03.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2004] [Revised: 03/22/2004] [Accepted: 03/25/2004] [Indexed: 11/25/2022]
Abstract
We have tested if the high number of unfertilized ova and degenerated embryos found in superovulated goats previously treated with GnRH antagonist can be related to a prolongation of gonadotrophin down-regulation and/or alterations in follicular function during the period of administration of the superovulatory treatment, around 4 days after the end of the antagonist treatment. A total of 15 does were treated with intravaginal progestagen sponges and daily injections of 0.5mg of the GnRH antagonist Antarelix for 6 days, while 5 does acted as controls receiving saline. During the antagonist treatment, the mean plasma LH concentration was lower in treated than control goats (0.5 +/- 0.2 versus 0.7 +/- 0.5 ng/ml, P < 0.0005 ); however, the FSH levels remained unaffected (0.8 +/- 0.4 versus 0.8 +/- 0.5 ng/ml). In this period, treated does also showed an increase in the number of small follicles with 2-3 mm in size ( 10.7 +/- 0.7 versus 8.4 +/- 0.6, P < 0.05), and a decrease in both the number of follicles > or =4 mm in size ( 5.0 +/- 0.3 versus 6.8 +/- 0.5, P < 0.005) and the secretion of inhibin A (120.9 +/- 10.7 versus 151.6 +/- 12.6 pg/ml, P < 0.05). After cessation of the antagonist treatment, there was an increase in LH levels in treated goats from the day after the last Antarelix injection (Day 1), so that LH levels were the same as controls on Day 3 (0.6 +/- 0.1 versus 0.6 +/- 0.2 ng/ml). However, there were even greater numbers of small follicles than during the period of antagonist injections (15.4 +/- 0.6 in treated versus 8.9 +/- 0.7 in control, P < 0.0005 ). Moreover, the number of > or =4 mm follicles and the secretion of inhibin A remained lower in treated goats (3.9 +/- 0.3 follicles and 84.4 +/- 7.0 pg/ml versus 5.4 +/- 0.5 follicles, P < 0.05 and 128.9 +/- 14.2 pg/ml, P < 0.05 ). These results indicate that pituitary secretion of gonadotrophins is restored shortly after the end of antagonist treatment, but activity of ovarian follicles is affected.
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Affiliation(s)
- A Gonzalez-Bulnes
- Departamento de Reproducción Animal INIA, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain.
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36
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Phillips DJ. Activins, inhibins and follistatins in the large domestic species. Domest Anim Endocrinol 2005; 28:1-16. [PMID: 15620803 DOI: 10.1016/j.domaniend.2004.05.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Accepted: 05/31/2004] [Indexed: 11/26/2022]
Abstract
The activins and inhibins are members of the transforming growth factor-beta (TGF-beta) superfamily and, along with follistatin, a high affinity binding protein of activin, form a group of interrelated factors originally isolated for their role in regulating the release of follicle-stimulating hormone (FSH). Knowledge of their function, particularly that of activin, has expanded since being originally isolated, such that they are now regarded as important paracrine regulators in many cellular systems. This review summarizes the biology of these proteins as has been established in the large domestic animals. While the majority of data relate to the pituitary, ovary, uterus/placenta and testis, consideration is also given to emerging roles in inflammatory processes and in non-reproductive tissues or systems.
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Affiliation(s)
- David J Phillips
- Center for Molecular Reproduction & Endocrinology, Monash Institute of Reproduction & Development, Monash University, Clayton, Vic. 3168, Australia.
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de Kretser DM, Buzzard JJ, Okuma Y, O'Connor AE, Hayashi T, Lin SY, Morrison JR, Loveland KL, Hedger MP. The role of activin, follistatin and inhibin in testicular physiology. Mol Cell Endocrinol 2004; 225:57-64. [PMID: 15451568 DOI: 10.1016/j.mce.2004.07.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The role of the inhibins, activins and follistatins in testicular function are being more clearly defined following studies describing the cellular localisation of these proteins to the testis and the availability of specific assay systems enabling measurement of these proteins. Taken together with the results of targetted gene inactivation experiments, several concepts emerge. Inhibin B is predominantly produced by the Sertoli cell in many adult male mammals whereas there is a perinatal peak of inhibin A in the rat. In contrast, activin A has its highest concentrations in the immediate post-natal period during which it is involved in the developmental regulation of both germ cells and Sertoli cells being modulated by follistatin. Activin A levels are considerably lower in the adult testis but Sertoli cell production is stimulated by interleukin-1 and inhibited by FSH. Little is known about the production of activin B due to the absence of a suitable assay but the beta(B) subunit mRNA is expressed in germ cells and Sertoli cells and is stage-dependent. This pattern of expression suggest that it may be involved in autocrine or paracrine actions within the seminiferous epithelium.
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Affiliation(s)
- D M de Kretser
- Monash Institute of Reproduction and Development and the ARC Centre of Excellence in Biotechnology and Development, Monash University, Clayton, Melbourne, Vic. 3168, Australia.
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Gold EJ, O'Bryan MK, Mellor SL, Cranfield M, Risbridger GP, Groome NP, Fleming JS. Cell-specific expression of betaC-activin in the rat reproductive tract, adrenal and liver. Mol Cell Endocrinol 2004; 222:61-9. [PMID: 15249126 DOI: 10.1016/j.mce.2004.05.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Accepted: 05/06/2004] [Indexed: 11/30/2022]
Abstract
betaC-activin expression was assessed in rat tissues, using reverse transcription and real-time polymerase chain reaction, Western blotting and immunohistochemistry with a specific monoclonal antibody. betaC-activin mRNA was predominantly expressed in liver, but significant amounts were found in rat whole pituitary extracts (n = 5), and in three of five extracts of ovary, testis, and adrenal gland. Specific betaC-activin immunoreactivity was demonstrated in the cytoplasm of hepatocytes, neurosecretory cell terminals in posterior pituitary, ovarian primordial follicles, theca interna, large luteal cells and rete ovarii, spermatogonia, pachytene spermatocytes and Leydig cells of the testis, uterine endometrium, oviduct epithelium and zona glomerulosa of the adrenal. The observation of stage-specific expression in gonadal cells suggests this activin subunit has specific roles, different from those of other activin/inhibin subunits. Small amounts of mRNA in the presence of significant betaC-activin protein highlights the importance of examining betaC-activin expression at both the mRNA and protein level.
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Affiliation(s)
- Elspeth J Gold
- Department of Anatomy and Structural Biology and Centre for Gene Research, University of Otago, School of Medical Sciences, P.O. Box 913, Dunedin, New Zealand
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Crawford JL, McNeilly JR, McNeilly AS. No Evidence for Pituitary Priming to Gonadotropin-Releasing Hormone in Relation to Luteinizing Hormone (LH) Secretion Prior to the Preovulatory LH Surge in Ewes1. Biol Reprod 2004; 71:224-35. [PMID: 15031142 DOI: 10.1095/biolreprod.104.027615] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The purpose of this study was to determine the occurrence of and the regulatory mechanisms involved in priming of the pituitary to GnRH before the preovulatory LH surge in sheep. Experiment 1: Forty-two ewes had progestagen devices removed after 14 days and were assigned to luteal (Lut) or follicular (Foll) groups. Fifteen days later, blood sampling was initiated either immediately or 36 h after induced luteolysis in groups Lut and Foll, respectively. After 4 h, ewes were administered either saline (n = 5) or 250 ng (n = 8) or 10 microg (n = 8) of GnRH. Five ewes per treatment group were killed 1 h later, while remaining animals were blood sampled for a further 7 h. Experiment 2: Eighteen ewes were allocated to Lut and Foll groups (described above). Blood samples were collected from 2 h before GnRH (10 microg) treatment until 7 h after. Despite up-regulated GnRH-R mRNA levels in Foll ewes, pituitary content and plasma levels of LH and LHbeta mRNA levels were similar between groups. Mean FSHbeta mRNA and plasma FSH levels were elevated in Lut ewes but declined after GnRH treatment. Inversely, plasma estradiol and inhibin-A concentrations were higher in Foll ewes and declined after GnRH treatment. Fewer LH(+ve)/secretogranin II(-ve) (SgII(-ve)) granules were present in gonadotropes of Foll ewes, coincident with increased basal LH levels. Fewer smaller sized granules were present after GnRH treatment. In conclusion, there was no evidence of self-priming before onset of the preovulatory LH surge. Constitutive release of LH(+ve)/SgII(-ve) granules may maintain basal LH levels while smaller sized, presumably mature granules may be preferentially released after GnRH stimulation.
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Affiliation(s)
- J L Crawford
- Human Reproductive Sciences Unit, Medical Research Council, University of Edinburgh Centre for Reproductive Biology, Edinburgh EH16 4SB, United Kingdom.
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Gonzalez-Bulnes A, Garcia-Garcia RM, Carrizosa JA, Urrutia B, Souza CJH, Cocero MJ, Lopez-Sebastian A, McNeilly AS. Plasma inhibin A determination at start superovulatory FSH treatments is predictive for embryo outcome in goats. Domest Anim Endocrinol 2004; 26:259-66. [PMID: 15036379 DOI: 10.1016/j.domaniend.2003.11.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2003] [Accepted: 11/21/2003] [Indexed: 11/16/2022]
Abstract
To test whether inhibin A assays can be used for the prediction of yields in embryo programmes in goats, 50 does were treated with 45 mg FGA sponges (Chronogest) for 16 days plus a single dose of 100 microg i.m. cloprostenol on Day 14, just before the start of administration of eight doses of 1.25 ml of Ovagen twice daily for 4 days. At first FSH injection, the number and size of all follicles > or =2 mm was assessed by transrectal ultrasound and plasma inhibin A levels were measured by specific dimeric assay. There was a positive correlation between number of follicles > or =6 mm (8.8 +/- 0.5) and inhibin A levels at first FSH dose (193.2 +/- 14.5 pg/ml, P<0.05). The mean number of corpora lutea on Day 7 after sponge removal was related to the total number of follicles with a diameter of 2-6 mm at the onset of the FSH treatment (15.3 +/- 0.7, P<0.05). The total number of embryos recovered was related to the number of follicles with 4-6 mm in size (6.2 +/- 0.5, P<0.05) and to the inhibin A levels at first FSH dose (P<0.05). These results suggest that follicles > or =4 mm are the source of inhibin prior to FSH stimulation and are the main source of oocytes resulting in the number of viable embryos recovered after a superovulatory treatment. Hence, the response to superovulatory treatments in goats in terms of the number of embryos can be predicted from either the population of follicles determined by ultrasound or the plasma inhibin A levels at start of the superovulatory FSH treatment.
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Affiliation(s)
- A Gonzalez-Bulnes
- Departamento de Reproduccion Animal, INIA, Avda Puerta de Hierro s/n, 28040-Madrid, Spain.
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Gonzalez-Bulnes A, Santiago-Moreno J, Garcia-Garcia RM, Souza CJH, Lopez-Sebastian A, McNeilly AS. Effect of GnRH antagonists treatment on gonadotrophin secretion, follicular development and inhibin A secretion in goats. Theriogenology 2004; 61:977-85. [PMID: 14757481 DOI: 10.1016/j.theriogenology.2003.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of this study was to determine, for goats, the effects of daily doses of GnRH antagonist on ovarian endocrine and follicular function. Ten does were given 45 mg FGA intravaginal sponges and then five were treated with daily injections of 0.5mg of the GnRH antagonist Teverelix for 11 days from 2 days after the day of sponge insertion, while five does acted as controls. Pituitary activity was monitored by measuring plasma FSH and LH daily from 2 days before the first GnRH injection to Day 12. Follicular activity was determined by ultrasonographic monitoring and by assessing plasma inhibin A levels during the same period. In treated does, the FSH levels decreased linearly (0.8 +/- 0.1 ng/ml to 0.5 +/- 0.1 ng/ml, P < 0.01) and remained lower than the mean concentration in control goats (0.8 +/- 0.1 ng/ml, P < 0.005). LH levels were also lower during the period of antagonist treatment (0.6 +/- 0.2 ng/ml versus 0.4 +/- 0.1 ng/ml, P < 0.0005). During GnRH antagonist treatment, there was a significant decrease in the number of large follicles (> or = 6 mm) from Day 3 of treatment (1.2 +/- 0.6, P < 0.0001), with no large follicles from Day 9. The number of medium follicles (4-5 mm in size) also decrease during the period of treatment (4.2 +/- 0.7 to 1.0 +/- 0.6, P < 0.0001), leading to a significant decrease in inhibin A levels when compared to the control (143.7 +/- 31.3 pg/ml versus 65.2 +/- 19.1 pg/ml, P < 0.00005). In contrast, the number of small follicles (2-3 mm) increased in treated goats from Day 4 of treatment (9.6 +/- 2.9 to 20.2 +/- 6.3, P < 0.005). Such data indicate that GnRH antagonist reduced plasma levels of FSH and LH with suppression of the growth of large dominant ovarian follicles and a two-fold increase in number of smaller follicles. The results confirm that GnRH antagonist treatment can be used in goats to control gonadotrophin secretion and ovarian follicle growth in superovulatory regimes.
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Affiliation(s)
- A Gonzalez-Bulnes
- Departamento de Reproducción Animal INIA. Avda. Puerta de Hierro s/n, Madrid, Spain.
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Wheaton JE, Godfrey RW. Plasma LH, FSH, testosterone, and age at puberty in ram lambs actively immunized against an inhibin alpha-subunit peptide. Theriogenology 2003; 60:933-41. [PMID: 12935870 DOI: 10.1016/s0093-691x(03)00104-3] [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: 10/27/2022]
Abstract
Active immunization against inhibin has been shown to advance puberty and increase ovulation rate in ewe lambs; but in ram lambs, effects on puberty and sperm production are equivocal. The objective of the present study was to determine whether active immunization against an inhibin alpha-subunit peptide advances the onset of puberty in ram lambs. St. Croix hair sheep ram lambs were assigned to inhibin-immunized (n = 7) and control (n = 8) treatment groups. Lambs in the inhibin-immunized group were immunized against a synthetic peptide-carrier protein conjugate, alpha-(1-25)-human alpha-globulin (halpha-G), and control lambs were immunized against halpha-G. Lambs were immunized at 3, 7, 13, 19, 25, 31, and 37 weeks of age. On the day of immunization a blood sample was collected and lambs were weighed. Another blood sample was collected 1 week following each immunization. At 20 weeks of age additional blood samples were collected at 20 min intervals for 8h. Beginning at 20 weeks of age and at weekly intervals thereafter, scrotal circumference (SC) was measured and semen was collected using electroejaculation. A subsequent ejaculate was collected 1 week following onset of puberty, which was defined as the week of age when an ejaculate first contained > or =50 x 10(6) sperm cells. In control lambs, plasma alpha-(1-25)-antibody (Ab) was nondetectable. In inhibin-immunized lambs, alpha-(1-25)-Ab titer increased from 7 to 25 weeks of age and then plateaued at a level that varied (P<0.001) among animals. Body weight and SC of control and inhibin-immunized lambs were similar at the onset of puberty. At pubertal onset inhibin-immunized lambs were older than control lambs (31.9+/-0.5 vs. 29.5+/-0.7 weeks of age, P<0.05). Plasma FSH concentrations were similar in control and inhibin-immunized lambs from 3 to 38 weeks of age. Plasma LH levels were lower (P<0.01) in inhibin-immunized than control lambs. During the 8-h blood sampling period at 20 weeks of age, LH and testosterone concentrations were lower (P<0.05) in inhibin-immunized than control ram lambs, and the LH pulse frequency was similar in the two groups of animals. The decreased LH secretion is consistent with the immunoneutralization of a putative inhibin alpha-subunit-related peptide that stimulates LH secretion in ram lambs. Present findings show that active immunization against an inhibin alpha-peptide delays rather than advances puberty in ram lambs.
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Affiliation(s)
- J E Wheaton
- Department of Animal Science, University of Minnesota, St. Paul, MN 55108, USA.
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