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Rulli SB, Ahtiainen P, Ratner LD, Jonas K, Calandra RS, Poutanen M, Huhtaniemi I. Elevated chorionic gonadotropic hormone in transgenic mice induces parthenogenetic activation and ovarian teratomas. Mol Cell Endocrinol 2024; 587:112214. [PMID: 38537882 DOI: 10.1016/j.mce.2024.112214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 02/25/2024] [Accepted: 03/19/2024] [Indexed: 04/13/2024]
Abstract
Both male and female reproductive functions are impacted by altered gonadotrophin secretion and action, which may also influence the development of endocrine tumours. To ascertain if chronic hypersecretion of human chorionic gonadotropin (hCG) contributes to the development of gonadal tumours, double transgenic (TG) mice that overexpress hCGα- and β-subunits were analysed. By the age of two months, ovarian tumours with characteristics of teratomas developed with 100% penetrance. Teratomas were also seen in wild-type ovaries orthotopically transplanted into TG mice, demonstrating an endocrine/paracrine mechanism for the hCG-induced ovarian tumorigenesis. Both in vitro and in vivo experiments showed oocyte parthenogenetic activation in TG females. In addition, ovaries showed reduced ovulatory gene expression, inhibited ERK1/2 phosphorylation, and impaired cumulus cell expansion. Hence, persistently high endocrine hCG activity causes parthenogenetic activation and development of ovarian teratomas, along with altered follicle development and impaired ERK1/2 signalling, offering a novel mechanism associated with the molecular pathogenesis of ovarian teratomas.
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Affiliation(s)
- Susana B Rulli
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland; Instituto de Biología y Medicina Experimental-CONICET, Vuelta de Obligado 2490, 1428, Buenos Aires, Argentina; Centro de Estudios Biomédicos Básicos, Aplicados y Desarrollo (CEBBAD), Universidad Maimónides, Hidalgo 775, C1405BCK, Ciudad Autónoma de Buenos Aires, Argentina.
| | - Petteri Ahtiainen
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
| | - Laura D Ratner
- Instituto de Biología y Medicina Experimental-CONICET, Vuelta de Obligado 2490, 1428, Buenos Aires, Argentina
| | - Kim Jonas
- Department of Digestion, Metabolism and Reproduction, Institute of Reproductive and Developmental Biology, Hammersmith Campus, Imperial College London, London, W12 0NN, UK; Department of Women and Children's Health, School of Population and Life Course Sciences, King's College London, London, SE1 1UL, UK
| | - Ricardo S Calandra
- Instituto de Biología y Medicina Experimental-CONICET, Vuelta de Obligado 2490, 1428, Buenos Aires, Argentina
| | - Matti Poutanen
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
| | - Ilpo Huhtaniemi
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland; Department of Digestion, Metabolism and Reproduction, Institute of Reproductive and Developmental Biology, Hammersmith Campus, Imperial College London, London, W12 0NN, UK
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Liu Y, Fan H, Kang X, Hao Y, Wang N, Zheng H, Li Y, Kang S. A rare germline BMP15 missense mutation causes hereditary ovarian immature teratoma in human. Proc Natl Acad Sci U S A 2024; 121:e2310409121. [PMID: 38427603 DOI: 10.1073/pnas.2310409121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 01/11/2024] [Indexed: 03/03/2024] Open
Abstract
Ovarian immature teratomas (OITs) are malignant tumors originating from the ovarian germ cells that mainly occur during the first 30 y of a female's life. Early age of onset strongly suggests the presence of susceptibility gene mutations for the disease yet to be discovered. Whole exon sequencing was used to screen pathogenic mutations from pedigrees with OITs. A rare missense germline mutation (C262T) in the first exon of the BMP15 gene was identified. In silico calculation suggested that the mutation could impair the formation of mature peptides. In vitro experiments on cell lines confirmed that the mutation caused an 84.7% reduction in the secretion of mature BMP15. Clinical samples from OIT patients also showed a similar pattern of decrease in the BMP15 expression. In the transgenic mouse model, the spontaneous parthenogenetic activation significantly increased in oocytes carrying the T allele. Remarkably, a mouse carrying the T allele developed the phenotype of OIT. Oocyte-specific RNA sequencing revealed that abnormal activation of the H-Ras/MAPK pathway might contribute to the development of OIT. BMP15 was identified as a pathogenic gene for OIT which improved our understanding of the etiology of OIT and provided a potential biomarker for genetic screening of this disorder.
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Affiliation(s)
- Yakun Liu
- Department of Gynecology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Hongwei Fan
- Department of Gynecology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Xi Kang
- Department of Surgery, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Yuntao Hao
- Department of Gynecology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Na Wang
- Department of Molecular Biology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Hui Zheng
- Nanjing Personal Oncology Biotechnology Co., Ltd., Nanjing, Jiangsu 211103, China
| | - Yan Li
- Department of Molecular Biology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | - Shan Kang
- Department of Gynecology, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, China
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Ludwig CLM, Bohleber S, Lapp R, Rebl A, Wirth EK, Langhammer M, Schweizer U, Weitzel JM, Michaelis M. Alterations in gonadotropin, apoptotic and metabolic pathways in granulosa cells warrant superior fertility of the Dummerstorf high fertility mouse line 1. J Ovarian Res 2023; 16:32. [PMID: 36739419 PMCID: PMC9898973 DOI: 10.1186/s13048-023-01113-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/29/2023] [Indexed: 02/06/2023] Open
Abstract
The development and maturation of ovarian follicles is a complex and highly regulated process, which is essential for successful ovulation. During recent decades, several mouse models provided insights into the regulation of folliculogenesis. In contrast to the commonly used transgenic or knockout mouse models, the Dummerstorf high-fertility mouse line 1 (FL1) is a worldwide unique selection experiment for increased female reproductive performance and extraordinary high fertility. Interactions of cycle-related alterations of parameters of the hypothalamic pituitary gonadal axis and molecular factors in the ovary lead to improved follicular development and therefore increased ovulation rates in FL1 mice. FL1 females almost doubled the number of ovulated oocytes compared to the unselected control mouse line. To gain insights into the cellular mechanisms leading to the high fertility phenotype we used granulosa cells isolated from antral follicles for mRNA sequencing. Based on the results of the transcriptome analysis we additionally measured hormones and growth factors associated with follicular development to complement the picture of how the signaling pathways are regulated. While IGF1 levels are decreased in FL1 mice in estrus, we found no differences in insulin, prolactin and oxytocin levels in FL1 mice compared to the control line. The results of the mRNA sequencing approach revealed that the actions of insulin, prolactin and oxytocin are restricted local to the granulosa cells, since hormonal receptor expression is differentially regulated in FL1 mice. Additionally, numerous genes, which are involved in important gonadotropin, apoptotic and metabolic signaling pathways in granulosa cells, are differentially regulated in granulosa cells of FL1 mice.We showed that an overlap of different signaling pathways reflects the crosstalk between gonadotropin and growth factor signaling pathways, follicular atresia in FL1 mice is decreased due to improved granulosa cell survival and by improving the efficiency of intracellular signaling, glucose metabolism and signal transduction, FL1 mice have several advantages in reproductive performance and therefore increased the ovulation rate. Therefore, this worldwide unique high fertility model can provide new insights into different factors leading to improved follicular development and has the potential to improve our understanding of high fertility.
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Affiliation(s)
| | - Simon Bohleber
- grid.10388.320000 0001 2240 3300Institut für Biochemie und Molekularbiologie (IBMB), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Rebecca Lapp
- grid.418188.c0000 0000 9049 5051Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Alexander Rebl
- grid.418188.c0000 0000 9049 5051Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Eva Katrin Wirth
- grid.6363.00000 0001 2218 4662Department of Endocrinology and Metabolism, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany ,grid.452396.f0000 0004 5937 5237DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany
| | - Martina Langhammer
- grid.418188.c0000 0000 9049 5051Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Ulrich Schweizer
- grid.10388.320000 0001 2240 3300Institut für Biochemie und Molekularbiologie (IBMB), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Joachim M. Weitzel
- grid.418188.c0000 0000 9049 5051Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Marten Michaelis
- grid.418188.c0000 0000 9049 5051Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
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Ludwig CLM, Bohleber S, Rebl A, Wirth EK, Venuto MT, Langhammer M, Schweizer U, Weitzel JM, Michaelis M. Endocrine and molecular factors of increased female reproductive performance in the Dummerstorf high-fertility mouse line FL1. J Mol Endocrinol 2022; 69:285-298. [PMID: 35388794 PMCID: PMC9175557 DOI: 10.1530/jme-22-0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 04/06/2022] [Indexed: 11/25/2022]
Abstract
The Dummerstorf high-fertility mouse line FL1 is a worldwide unique selection experiment for increased female reproductive performance. After more than 190 generations of selection, these mice doubled the amount of offspring per litter compared to the unselected control line. FL1 females have a superior lifetime fecundity and the highest Silver fecundity index that has been described in mice, while their offspring show no signs of growth retardation. The reasons for the increased reproductive performance remained unclear. Thus, this study aims to characterize the Dummerstorf high-fertility mouse line FL1 on endocrine and molecular levels on the female side. We analyzed parameters of the hypothalamic pituitary gonadal axis on both hormonal and transcriptional levels. Gonadotropin-releasing hormone and follicle-stimulating hormone (FSH) concentrations were decreased in FL1 throughout the whole estrous cycle. Luteinizing hormone (LH) was increased in FL1 mice in estrus. Progesterone concentrations were decreased in estrus in FL1 mice and not affected in diestrus. We used a holistic gene expression approach in the ovary to obtain a global picture of how the high-fertility phenotype is achieved. We found several differentially expressed genes in the ovaries of FL1 mice that are associated with different female fertility traits. Our results indicate that ovulation rates in mice can be increased despite decreased FSH levels. Cycle-related alterations of progesterone and LH levels have the potential to improve follicular maturation, and interactions of endocrine and molecular factors lead to enhanced follicular survival, more successful folliculogenesis and therefore higher ovulation rates in female FL1 mice.
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Affiliation(s)
| | - Simon Bohleber
- Institut für Biochemie und Molekularbiologie (IBMB), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Alexander Rebl
- Institute of Genome Biology, Fish Genetics Unit, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Eva Katrin Wirth
- Department of Endocrinology and Metabolism, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany
| | - Marzia Tindara Venuto
- Institute of Reproductive Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Martina Langhammer
- Institute of Genetics and Biometry, Service Group Model Laboratory Animals, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie (IBMB), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Joachim M Weitzel
- Institute of Reproductive Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
- Correspondence should be addressed to J M Weitzel or M Michaelis: or
| | - Marten Michaelis
- Institute of Reproductive Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
- Correspondence should be addressed to J M Weitzel or M Michaelis: or
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5
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Cheng J, Liu Y. Knockout of cyclin B1 in granulosa cells causes female subfertility. Cell Cycle 2022; 21:1867-1878. [PMID: 35536551 PMCID: PMC9359391 DOI: 10.1080/15384101.2022.2074740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
In mammalian cells, cyclin B1 plays a pivotal role in mitotic and meiotic progression. It has been reported that infertility occurs after disruption of cyclin B1 (Ccnb1) in male germ cells and oocytes. However, it remains to be elucidated whether the specific disruption of Ccnb1 in granulosa cells influences the reproductive activity of female mice. Amhr2 is expressed in granulosa cells (GCs) of the ovary. Here, we mated Ccnb1Flox/Flox mice with a transgenic mouse strain expressing Amhr2-Cre to generate GC-specific Ccnb1 knockout mice. The results showed that Ccnb1 Flox/Flox, Amhr2-Cre (Ccnb1 cKO) mice were subfertile but had normal oocyte meiotic progress, spindle shape and protein levels of cohesin subunits REC8 and SMC3 on arm chromosomes during meiosis I. A further study found that 32.4% of oocytes from Ccnb1 cKO mice exhibited chromosome condensation and spindle disassembly after the first polar body extrusion and failed to undergo second meiosis, which was never found in oocytes from Ccnb1Flox/Flox mice. In addition, the percentages of 2-cell embryos, morulas, and blastocysts in the Ccnb1 mutant group were all dramatically decreased compared to those in the Ccnb1Flox/Flox group (39.2% vs. 86.8%, 26.0% vs. 85.0%, 19.1% vs. 85.8%, respectively). Therefore, GC-specific Ccnb1 deletion in mice could cause fewer and poor-quality blastocysts and subsequent subfertility, which plays an important role in understanding the function of cyclin B1 in reproduction.
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Affiliation(s)
- Jinmei Cheng
- School of Medicine, Institute of Reproductive Medicine, Nantong University, Nantong, Jiangsu, China.,State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, Xicheng, China
| | - Yixun Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, Xicheng, China
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6
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The Roles of Luteinizing Hormone, Follicle-Stimulating Hormone and Testosterone in Spermatogenesis and Folliculogenesis Revisited. Int J Mol Sci 2021; 22:ijms222312735. [PMID: 34884539 PMCID: PMC8658012 DOI: 10.3390/ijms222312735] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 12/17/2022] Open
Abstract
Spermatogenesis and folliculogenesis involve cell–cell interactions and gene expression orchestrated by luteinizing hormone (LH) and follicle-stimulating hormone (FSH). FSH regulates the proliferation and maturation of germ cells independently and in combination with LH. In humans, the requirement for high intratesticular testosterone (T) concentration in spermatogenesis remains both a dogma and an enigma, as it greatly exceeds the requirement for androgen receptor (AR) activation. Several data have challenged this dogma. Here we report our findings on a man with mutant LH beta subunit (LHβ) that markedly reduced T production to 1–2% of normal., but despite this minimal LH stimulation, T production by scarce mature Leydig cells was sufficient to initiate and maintain complete spermatogenesis. Also, in the LH receptor (LHR) knockout (LuRKO) mice, low-dose T supplementation was able to maintain spermatogenesis. In addition, in antiandrogen-treated LuRKO mice, devoid of T action, the transgenic expression of a constitutively activating follicle stimulating hormone receptor (FSHR) mutant was able to rescue spermatogenesis and fertility. Based on rodent models, it is believed that gonadotropin-dependent follicular growth begins at the antral stage, but models of FSHR inactivation in women contradict this claim. The complete loss of FSHR function results in the complete early blockage of folliculogenesis at the primary stage, with a high density of follicles of the prepubertal type. These results should prompt the reassessment of the role of gonadotropins in spermatogenesis, folliculogenesis and therapeutic applications in human hypogonadism and infertility.
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Jonas KC, Rivero Müller A, Oduwole O, Peltoketo H, Huhtaniemi I. The Luteinizing Hormone Receptor Knockout Mouse as a Tool to Probe the In Vivo Actions of Gonadotropic Hormones/Receptors in Females. Endocrinology 2021; 162:6144965. [PMID: 33605422 PMCID: PMC8171189 DOI: 10.1210/endocr/bqab035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Indexed: 11/25/2022]
Abstract
Mouse models with altered gonadotropin functions have provided invaluable insight into the functions of these hormones/receptors. Here we describe the repurposing of the infertile and hypogonadal luteinizing hormone receptor (LHR) knockout mouse model (LuRKO), to address outstanding questions in reproductive physiology. Using crossbreeding strategies and physiological and histological analyses, we first addressed the physiological relevance of forced LHR homomerization in female mice using BAC expression of 2 ligand-binding and signaling deficient mutant LHR, respectively, that have previously shown to undergo functional complementation and rescue the hypogonadal phenotype of male LuRKO mice. In female LuRKO mice, coexpression of signaling and binding deficient LHR mutants failed to rescue the hypogonadal and anovulatory phenotype. This was apparently due to the low-level expression of the 2 mutant LHR and potential lack of luteinizing hormone (LH)/LHR-dependent pleiotropic signaling that has previously been shown at high receptor densities to be essential for ovulation. Next, we utilized a mouse model overexpressing human chorionic gonadotropin (hCG) with increased circulating "LH/hCG"-like bioactivity to ~40 fold higher than WT females, to determine if high circulating hCG in the LuRKO background could reveal putative LHR-independent actions. No effects were found, thus, suggesting that LH/hCG mediate their gonadal and non-gonadal effects solely via LHR. Finally, targeted expression of a constitutively active follicle stimulating hormone receptor (FSHR) progressed antral follicles to preovulatory follicles and displayed phenotypic markers of enhanced estrogenic activity but failed to induce ovulation in LuRKO mice. This study highlights the critical importance and precise control of functional LHR and FSHR for mediating ovarian functions and of the potential repurposing of existing genetically modified mouse models in answering outstanding questions in reproductive physiology.
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Affiliation(s)
- Kim Carol Jonas
- Department of Women and Children’s Health, King’s College London,
London SE1 1UL, UK
- Institute of Reproductive and Developmental Biology, Department of Metabolism,
Digestion and Reproduction, Imperial College London, London W12
0NN, UK
- Correspondence: Dr Kim Jonas, Department of Women and Children’s Health, King’s College London,
London SE1 1UL, UK; Institute of Reproductive and Developmental Biology, Department of
Metabolism, Digestion and Reproduction, Imperial College London, London W12 0NN, UK.
; or Prof. Ilpo Huhtaniemi, Institute of Reproductive and
Developmental Biology, Department of Metabolism, Digestion and Reproduction, Imperial
College London, London, W12 0NN, UK; Institute for Biomedicine, Department of Physiology,
University of Turku, 20520 Turku, Finland.
| | - Adolfo Rivero Müller
- Institute for Biomedicine, Department of Physiology, University of
Turku, 20520 Turku, Finland
- Department of Biochemistry and Molecular Biology, Medical University of
Lublin, 20-093 Lublin, Poland
| | - Olayiwola Oduwole
- Institute of Reproductive and Developmental Biology, Department of Metabolism,
Digestion and Reproduction, Imperial College London, London W12
0NN, UK
| | - Hellevi Peltoketo
- Institute of Reproductive and Developmental Biology, Department of Metabolism,
Digestion and Reproduction, Imperial College London, London W12
0NN, UK
- Laboratory of Cancer Genetics and Tumour Biology, Cancer and Translational
Medicine Research Unit, Biocenter Oulu and University of Oulu,
90220 Oulu, Finland
| | - Ilpo Huhtaniemi
- Institute of Reproductive and Developmental Biology, Department of Metabolism,
Digestion and Reproduction, Imperial College London, London W12
0NN, UK
- Institute for Biomedicine, Department of Physiology, University of
Turku, 20520 Turku, Finland
- Correspondence: Dr Kim Jonas, Department of Women and Children’s Health, King’s College London,
London SE1 1UL, UK; Institute of Reproductive and Developmental Biology, Department of
Metabolism, Digestion and Reproduction, Imperial College London, London W12 0NN, UK.
; or Prof. Ilpo Huhtaniemi, Institute of Reproductive and
Developmental Biology, Department of Metabolism, Digestion and Reproduction, Imperial
College London, London, W12 0NN, UK; Institute for Biomedicine, Department of Physiology,
University of Turku, 20520 Turku, Finland.
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Naser AA, Miyazaki T, Wang J, Takabayashi S, Pachoensuk T, Tokumoto T. MC4R mutant mice develop ovarian teratomas. Sci Rep 2021; 11:3483. [PMID: 33568756 PMCID: PMC7876032 DOI: 10.1038/s41598-021-83001-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 01/19/2021] [Indexed: 01/05/2023] Open
Abstract
Teratomas in mice, composed of different tissue types, are derived from primordial germ cells (PGCs) in the foetal gonads. The strongest candidate gene in the testicular teratoma locus (Ter) responsible for testicular teratoma formation was identified as mutation in Dnd1, Dnd1R178*. However, the phenotype of mice with a mutated Dnd1 gene was germ cell loss. This suggests that other genes are involved in teratoma formation. Testicular teratomas can also be induced experimentally (experimentally testicular teratomas: ETTs) in 129/Sv mice by transplanting E12.5 foetal testes into adult testes. Previously, we mapped the ett1 locus, which is the locus responsible for ETT formation on chromosome 18. By exome sequence analysis of the 129 and LTXBJ (LT) strains, we identified a missense mutation in the melanocortin 4 receptor (MC4R) gene among 8 genes in the ett1 region. The missense mutation causes a substitution of glycine 25 by serine. Thus, this gene is a candidate for ETT formation. We established the LT-ett1 congenic strain, which introduced the locus responsible for ETT formation genetically into the genomes of a testicular teratoma non-susceptible strain. In this study, we crossed LT-ett1 and a previously established LT-Ter strain to establish the double congenic strain LT-Ter-ett1. Also, we established a strain with a point mutation in the MC4R gene of the LT strain by genome editing, LT-MC4RG25S. Furthermore, double genetically modified strain LT-Ter-MC4RG25S was established to address the relation between Ter and MC4R. Surprisingly, highly developed ovarian teratomas (OTs), instead of testicular teratomas, appeared not only in the LT-Ter-MC4RG25S and LT-MC4RG25S strains but also in the LT-ett1 and LT-Ter-ett1 strains. The incidence of OT formation was high in double genetically modified strains. The results demonstrated that MC4R is one of the genes responsible for OT formation. It was suggested that the effect of the missense mutation in MC4R on teratoma formation was promoted by abnormal germ cell formation by the mutation in DND1.
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Affiliation(s)
- Abdullah An Naser
- Integrated Bioscience Section, Graduate School of Science and Technology, National University Corporation Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Takehiro Miyazaki
- Integrated Bioscience Section, Graduate School of Science and Technology, National University Corporation Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8529, Japan
- Department of Molecular Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo, Kyoto, 606-8501, Japan
| | - Jun Wang
- Department of Bioscience, Faculty of Science, Shizuoka University, Shizuoka, 422, Japan
| | - Shuji Takabayashi
- Laboratory Animal Facilities & Services, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
| | - Theeranukul Pachoensuk
- Integrated Bioscience Section, Graduate School of Science and Technology, National University Corporation Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Toshinobu Tokumoto
- Integrated Bioscience Section, Graduate School of Science and Technology, National University Corporation Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8529, Japan.
- Department of Bioscience, Faculty of Science, Shizuoka University, Shizuoka, 422, Japan.
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Mara JN, Zhou LT, Larmore M, Johnson B, Ayiku R, Amargant F, Pritchard MT, Duncan FE. Ovulation and ovarian wound healing are impaired with advanced reproductive age. Aging (Albany NY) 2020; 12:9686-9713. [PMID: 32407290 PMCID: PMC7288922 DOI: 10.18632/aging.103237] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 03/31/2020] [Indexed: 12/14/2022]
Abstract
Aging is associated with reduced tissue remodeling efficiency and increased fibrosis, characterized by excess collagen accumulation and altered matrix degradation. Ovulation, the process by which an egg is released from the ovary, is one of the most dynamic cycles of tissue wounding and repair. Because the ovary is one of the first organs to age, ovulation and ovarian wound healing is impaired with advanced reproductive age. To test this hypothesis, we induced superovulation in reproductively young and old mice and determined the numbers of eggs ovulated and corpora lutea (CLs), the progesterone producing glands formed post-ovulation. Reproductively old mice ovulated fewer eggs and had fewer CLs relative to young controls. Moreover, reproductively old mice exhibited a greater number of oocytes trapped within CLs and expanded cumulus oocyte complexes within unruptured antral follicles, indicative of failed ovulation. In addition, post-ovulatory tissue remodeling was compromised with age as evidenced by reduced CL vasculature, increased collagen, decreased hyaluronan, decreased cell proliferation and apoptosis, impaired wound healing capacity, and aberrant morphology of the ovarian surface epithelium (OSE). These findings demonstrate that ovulatory dysfunction is an additional mechanism underlying the age-related loss of fertility beyond the reduction of egg quantity and quality.
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Affiliation(s)
- Jamie N. Mara
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Luhan T. Zhou
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Megan Larmore
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA
| | - Brian Johnson
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA
| | - Rebecca Ayiku
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Farners Amargant
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Michele T. Pritchard
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Francesca E. Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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10
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Cleary JA, Tillitt DE, Vom Saal FS, Nicks DK, Claunch RA, Bhandari RK. Atrazine induced transgenerational reproductive effects in medaka (Oryzias latipes). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 251:639-650. [PMID: 31108297 DOI: 10.1016/j.envpol.2019.05.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/23/2019] [Accepted: 05/04/2019] [Indexed: 06/09/2023]
Abstract
Atrazine is presently one of the most abundantly used herbicides in the United States, and a common contaminant of natural water bodies and drinking waters in high-use areas. Dysregulation of reproductive processes has been demonstrated in atrazine exposed fish, including alteration of key endocrine pathways on hypothalamic-pituitary-gonadal (HPG) axis. However, the potential for atrazine-induced transgenerational inheritance of reproductive effects in fish has not been investigated. The present study examined the effects of early developmental atrazine exposure on transgenerational reproductive dysregulation in Japanese medaka (Oryzias latipes). F0 medaka were exposed to atrazine (ATZ, 5 or 50 μg/L), 17α-ethinylestradiol (EE2, 0.002 or 0.05 μg/L), or solvent control during the first twelve days of development with no subsequent exposure over three generations. This exposure overlapped with the critical developmental window for embryonic germ cell development, gonadogenesis, and sex determination. Exposed males and females of the F0 generation were bred to produce an F1 generation, and this was continued until the F2 generation. Sperm count and motility were not affected in F0 males; however, both parameters were significantly reduced in the males from F2 Low EE2 (0.002 μg/L), Low ATZ (5 μg/L), and High ATZ (50 μg/L) lineages. Fecundity was unaffected by atrazine or EE2 in F0 through F2 generations; however, fertilization rate was decreased in low atrazine and EE2 exposure lineages in the F2 generation. There were significant transgenerational differences in expression of the genes involved in steroidogenesis and DNA methylation. These results suggest that although early life exposure to atrazine did not cause significant phenotypes in the directly exposed F0 generation, subsequent generations of fish were at greater risk of reproductive dysfunction.
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Affiliation(s)
- Jacob A Cleary
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC 27412, USA
| | - Donald E Tillitt
- U.S. Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201, USA
| | - Frederick S Vom Saal
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Diane K Nicks
- U.S. Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201, USA
| | - Rachel A Claunch
- U.S. Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201, USA
| | - Ramji K Bhandari
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC 27412, USA.
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11
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McDonald R, Sadler C, Kumar TR. Gain-of-Function Genetic Models to Study FSH Action. Front Endocrinol (Lausanne) 2019; 10:28. [PMID: 30792692 PMCID: PMC6374295 DOI: 10.3389/fendo.2019.00028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/15/2019] [Indexed: 12/15/2022] Open
Abstract
Follicle-stimulating hormone (FSH) is a pituitary-derived gonadotropin that plays key roles in male and female reproduction. The physiology and biochemistry of FSH have been extensively studied for many years. Beginning in the early 1990s, coincident with advances in the then emerging transgenic animal technology, and continuing till today, several gain-of-function (GOF) models have been developed to understand FSH homeostasis in a physiological context. Our group and others have generated a number of FSH ligand and receptor GOF mouse models. An FSH GOF model when combined with Fshb null mice provides a powerful genetic rescue platform. In this chapter, we discuss different GOF models for FSH synthesis, secretion and action and describe additional novel genetic models that could be developed in the future to further refine the existing models.
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Affiliation(s)
- Rosemary McDonald
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
- Integrated Physiology Graduate Program, University of Colorado Anschutz Medical CampusAurora, IL, United States
| | - Carolyn Sadler
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
| | - T. Rajendra Kumar
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
- Integrated Physiology Graduate Program, University of Colorado Anschutz Medical CampusAurora, IL, United States
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical CampusAurora, IL, United States
- *Correspondence: T. Rajendra Kumar
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Szymańska K, Kałafut J, Rivero-Müller A. The gonadotropin system, lessons from animal models and clinical cases. ACTA ACUST UNITED AC 2018; 70:561-587. [PMID: 30264954 DOI: 10.23736/s0026-4784.18.04307-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review article centers upon family of gonadotropin hormones which consists of two pituitary hormones - follicle-stimulating hormone (FSH) and luteinizing hormone (LH) as well as one non-pituitary hormone - human chorionic gonadotropin (hCG) secreted by placenta, and their receptors. Gonadotropins play an essential role in proper sexual development, puberty, gametogenesis, maintenance of pregnancy and male sexual differentiation during the fetal development. They belong to the family of glycoprotein hormones thus they constitute heterodimeric proteins built of common α subunit and hormone-specific β-subunit. Hitherto, several mutations in genes encoding both gonadotropins and their receptors have been identified in humans. Their occurrence resulted in a number of different phenotypes including delayed puberty, primary amenorrhea, hermaphroditism, infertility and hypogonadism. In order to understand the effects of mutations on the phenotype observed in affected patients, detailed molecular studies are required to map the relationship between the structure and function of gonadotropins and their receptors. Nonetheless, in vitro assays are often insufficient to understand physiology. Therefore, several animal models have been developed to unravel the physiological roles of gonadotropins and their receptors.
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Huhtaniemi I. MECHANISMS IN ENDOCRINOLOGY: Hormonal regulation of spermatogenesis: mutant mice challenging old paradigms. Eur J Endocrinol 2018; 179:R143-R150. [PMID: 29959220 DOI: 10.1530/eje-18-0396] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 06/28/2018] [Indexed: 11/08/2022]
Abstract
The two pituitary gonadotrophins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and in particular LH-stimulated high intratesticular testosterone (ITT) concentration, are considered crucial for spermatogenesis. We have revisited these concepts in genetically modified mice, one being the LH receptor (R)-knockout mouse (LuRKO), the other a transgenic mouse expressing in Sertoli cells a highly constitutively active mutated Fshr (Fshr-CAM). It was found that full spermatogenesis was induced by exogenous testosterone treatment in LuRKO mice at doses that restored ITT concentration to a level corresponding to the normal circulating testosterone level in WT mice, ≈5 nmol/L, which is 1.4% of the normal high ITT concentration. When hypogonadal LuRKO and Fshr-CAM mice were crossed, the double-mutant mice with strong FSH signaling, but minimal testosterone production, showed near-normal spermatogenesis, even when their residual androgen action was blocked with the strong antiandrogen flutamide. In conclusion, our findings challenge two dogmas of the hormonal regulation of male fertility: (1) high ITT concentration is not necessary for spermatogenesis and (2) strong FSH stimulation can maintain spermatogenesis without testosterone. These findings have clinical relevance for the development of hormonal male contraception and for the treatment of idiopathic oligozoospermia.
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Affiliation(s)
- Ilpo Huhtaniemi
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, Hammersmith Campus, London, UK
- Department of Physiology, Institute of Biomedicine, University of Turku, Turku, Finland
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14
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Gilbert SB, Roof AK, Rajendra Kumar T. Mouse models for the analysis of gonadotropin secretion and action. Best Pract Res Clin Endocrinol Metab 2018; 32:219-239. [PMID: 29779578 PMCID: PMC5973545 DOI: 10.1016/j.beem.2018.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Gonadotropins are pituitary gonadotrope-derived glycoprotein hormones. They act by binding to G-protein coupled receptors on gonads. Gonadotropins play critical roles in reproduction by regulating both gametogenesis and steroidogenesis. Although biochemical and physiological studies provided a wealth of knowledge, gene manipulation techniques using novel mouse models gave new insights into gonadotropin synthesis, secretion and action. Both gain of function and loss of function mouse models for understanding gonadotropin action in a whole animal context have already been generated. Moreover, recent studies on gonadotropin actions in non-gonadal tissues challenged the central dogma of classical gonadotropin actions in gonads and revealed new signaling pathways in these non-gonadal tissues. In this Chapter, we have discussed our current understanding of gonadotropin synthesis, secretion and action using a variety of genetically engineered mouse models.
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Affiliation(s)
- Sara Babcock Gilbert
- Division of Reproductive Endocrinology and Infertility, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA; Division of Reproductive Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA; Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Allyson K Roof
- Division of Reproductive Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA; Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - T Rajendra Kumar
- Division of Reproductive Endocrinology and Infertility, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA; Division of Reproductive Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA; Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
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15
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Das N, Kumar TR. Molecular regulation of follicle-stimulating hormone synthesis, secretion and action. J Mol Endocrinol 2018; 60:R131-R155. [PMID: 29437880 PMCID: PMC5851872 DOI: 10.1530/jme-17-0308] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 02/07/2018] [Indexed: 12/11/2022]
Abstract
Follicle-stimulating hormone (FSH) plays fundamental roles in male and female fertility. FSH is a heterodimeric glycoprotein expressed by gonadotrophs in the anterior pituitary. The hormone-specific FSHβ-subunit is non-covalently associated with the common α-subunit that is also present in the luteinizing hormone (LH), another gonadotrophic hormone secreted by gonadotrophs and thyroid-stimulating hormone (TSH) secreted by thyrotrophs. Several decades of research led to the purification, structural characterization and physiological regulation of FSH in a variety of species including humans. With the advent of molecular tools, availability of immortalized gonadotroph cell lines and genetically modified mouse models, our knowledge on molecular mechanisms of FSH regulation has tremendously expanded. Several key players that regulate FSH synthesis, sorting, secretion and action in gonads and extragonadal tissues have been identified in a physiological setting. Novel post-transcriptional and post-translational regulatory mechanisms have also been identified that provide additional layers of regulation mediating FSH homeostasis. Recombinant human FSH analogs hold promise for a variety of clinical applications, whereas blocking antibodies against FSH may prove efficacious for preventing age-dependent bone loss and adiposity. It is anticipated that several exciting new discoveries uncovering all aspects of FSH biology will soon be forthcoming.
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Affiliation(s)
- Nandana Das
- Division of Reproductive Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, U.S.A
| | - T. Rajendra Kumar
- Division of Reproductive Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, U.S.A
- Division of Reproductive Endocrinology and Infertility, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, U.S.A
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, U.S.A
- Author for Correspondence: T. Rajendra Kumar, PhD, Edgar L. and Patricia M. Makowski Professor, Associate Vice-Chair of Research, Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Mail Stop 8613, Research Complex 2, Room # 15-3000B, 12700 E. 19th Avenue, Aurora, CO 80045, USA, Tel: 303-724-8689,
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16
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Oduwole OO, Peltoketo H, Poliandri A, Vengadabady L, Chrusciel M, Doroszko M, Samanta L, Owen L, Keevil B, Rahman NA, Huhtaniemi IT. Constitutively active follicle-stimulating hormone receptor enables androgen-independent spermatogenesis. J Clin Invest 2018; 128:1787-1792. [PMID: 29584617 PMCID: PMC5919831 DOI: 10.1172/jci96794] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 02/07/2018] [Indexed: 11/17/2022] Open
Abstract
Spermatogenesis is regulated by the 2 pituitary gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This process is considered impossible without the absolute requirement of LH-stimulated testicular testosterone (T) production. The role of FSH remains unclear because men and mice with inactivating FSH receptor (FSHR) mutations are fertile. We revisited the role of FSH in spermatogenesis using transgenic mice expressing a constitutively strongly active FSHR mutant in a LH receptor-null (LHR-null) background. The mutant FSHR reversed the azoospermia and partially restored fertility of Lhr-/- mice. The finding was initially ascribed to the residual Leydig cell T production. However, when T action was completely blocked with the potent antiandrogen flutamide, spermatogenesis persisted. Hence, completely T-independent spermatogenesis is possible through strong FSHR activation, and the dogma of T being a sine qua non for spermatogenesis may need modification. The mechanism for the finding appeared to be that FSHR activation maintained the expression of Sertoli cell genes considered androgen dependent. The translational message of our findings is the possibility of developing a new strategy of high-dose FSH treatment for spermatogenic failure. Our findings also provide an explanation of molecular pathogenesis for Pasqualini syndrome (fertile eunuchs; LH/T deficiency with persistent spermatogenesis) and explain how the hormonal regulation of spermatogenesis has shifted from FSH to T dominance during evolution.
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Affiliation(s)
- Olayiwola O Oduwole
- Institute of Reproductive and Developmental Biology (IRDB), Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom
| | - Hellevi Peltoketo
- Institute of Reproductive and Developmental Biology (IRDB), Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom.,Laboratory of Cancer Genetics and Tumor Biology, Cancer and Translational Medicine Research Unit/Laboratory Medicine, Biocenter Oulu and Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Ariel Poliandri
- Institute of Reproductive and Developmental Biology (IRDB), Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom.,Department of Molecular and Clinical Sciences, St. George's University of London, London, United Kingdom
| | - Laura Vengadabady
- Department of Target Sciences, GlaxoSmithKline, London, United Kingdom
| | | | - Milena Doroszko
- Department of Physiology, University of Turku, Turku, Finland
| | - Luna Samanta
- Department of Zoology, School of Life Sciences, Ravenshaw University, Cuttack, India
| | - Laura Owen
- Biochemistry Department, University Hospital of South Manchester, Manchester, United Kingdom
| | - Brian Keevil
- Biochemistry Department, University Hospital of South Manchester, Manchester, United Kingdom
| | - Nafis A Rahman
- Department of Physiology, University of Turku, Turku, Finland.,Department of Reproduction and Gynecological Endocrinology, Medical University of Bialystok, Bialystok, Poland
| | - Ilpo T Huhtaniemi
- Institute of Reproductive and Developmental Biology (IRDB), Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom.,Department of Physiology, University of Turku, Turku, Finland
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17
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Coss D. Regulation of reproduction via tight control of gonadotropin hormone levels. Mol Cell Endocrinol 2018; 463:116-130. [PMID: 28342855 PMCID: PMC6457911 DOI: 10.1016/j.mce.2017.03.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/16/2017] [Accepted: 03/21/2017] [Indexed: 01/04/2023]
Abstract
Mammalian reproduction is controlled by the hypothalamic-pituitary-gonadal axis. GnRH from the hypothalamus regulates synthesis and secretion of gonadotropins, LH and FSH, which then control steroidogenesis and gametogenesis. In females, serum LH and FSH levels exhibit rhythmic changes throughout the menstrual or estrous cycle that are correlated with pulse frequency of GnRH. Lack of gonadotropins leads to infertility or amenorrhea. Dysfunctions in the tightly controlled ratio due to levels slightly outside the normal range occur in a larger number of women and are correlated with polycystic ovaries and premature ovarian failure. Since the etiology of these disorders is largely unknown, studies in cell and mouse models may provide novel candidates for investigations in human population. Hence, understanding the mechanisms whereby GnRH regulates gonadotropin hormone levels will provide insight into the physiology and pathophysiology of the reproductive system. This review discusses recent advances in our understanding of GnRH regulation of gonadotropin synthesis.
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Affiliation(s)
- Djurdjica Coss
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA 92521, United States.
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18
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Oduwole OO, Peltoketo H, Huhtaniemi IT. Role of Follicle-Stimulating Hormone in Spermatogenesis. Front Endocrinol (Lausanne) 2018; 9:763. [PMID: 30619093 PMCID: PMC6302021 DOI: 10.3389/fendo.2018.00763] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/03/2018] [Indexed: 11/13/2022] Open
Abstract
Spermatogenesis is a concerted sequence of events during maturation of spermatogonia into spermatozoa. The process involves differential gene-expression and cell-cell interplay regulated by the key endocrine stimuli, i.e., follicle-stimulating hormone (FSH) and luteinizing hormone (LH)-stimulated testosterone. FSH affects independently and in concert with testosterone, the proliferation, maturation and function of the supporting Sertoli cells that produce regulatory signals and nutrients for the maintenance of developing germ cells. Rodents are able to complete spermatogenesis without FSH stimulus, but its deficiency significantly decreases sperm quantity. Men carrying loss-of-function mutation in the gene encoding the ligand (FSHB) or its receptor (FSHR) present, respectively, with azoospermia or suppressed spermatogenesis. Recently, the importance of high intratesticular testosterone concentration for spermatogenesis has been questioned. It was established that it can be completed at minimal intratesticular concentration of the hormone. Furthermore, we recently demonstrated that very robust constitutive FSHR action can rescue spermatogenesis and fertility of mice even when the testosterone stimulus is completely blocked. The clinical relevance of these findings concerns a new strategy of high-dose FSH in treatment of spermatogenic failure.
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Affiliation(s)
- Olayiwola O. Oduwole
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom
| | - Hellevi Peltoketo
- Cancer and Translational Medicine Research Unit, Laboratory of Cancer Genetics and Tumor Biology, Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Ilpo T. Huhtaniemi
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom
- Department of Physiology, University of Turku, Turku, Finland
- *Correspondence: Ilpo T. Huhtaniemi
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Khawajkie Y, Buckett W, Nguyen NMP, Mechtouf N, Ao A, Arseneau J, Slim R. Recurrent triploid digynic conceptions and mature ovarian teratomas: Are they different manifestations of the same genetic defect? Genes Chromosomes Cancer 2017; 56:832-840. [DOI: 10.1002/gcc.22484] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 07/17/2017] [Accepted: 07/17/2017] [Indexed: 11/05/2022] Open
Affiliation(s)
| | - William Buckett
- Department of Obstetrics and Gynecology; McGill University; Montreal Canada
| | - Ngoc Minh Phuong Nguyen
- Department of Obstetrics and Gynecology; McGill University; Montreal Canada
- Department of Human Genetics; McGill University; Montreal Canada
| | - Nawel Mechtouf
- Department of Human Genetics; McGill University; Montreal Canada
| | - Asangla Ao
- Department of Obstetrics and Gynecology; McGill University; Montreal Canada
- Department of Human Genetics; McGill University; Montreal Canada
| | - Jocelyne Arseneau
- Department of Pathology; McGill University; Montreal Canada
- Gynecologic Oncology Unit, McGill University Health Centre; Montreal Canada
| | - Rima Slim
- Division of Experimental Medicine; McGill University; Montreal Canada
- Department of Obstetrics and Gynecology; McGill University; Montreal Canada
- Department of Human Genetics; McGill University; Montreal Canada
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20
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Mouse Models for the Study of Synthesis, Secretion, and Action of Pituitary Gonadotropins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 143:49-84. [PMID: 27697204 DOI: 10.1016/bs.pmbts.2016.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Gonadotropins play fundamental roles in reproduction. More than 30years ago, Cga transgenic mice were generated, and more than 20years ago, the phenotypes of Cga null mice were reported. Since then, numerous mouse strains have been generated and characterized to address several questions in reproductive biology involving gonadotropin synthesis, secretion, and action. More recently, extragonadal expression, and in some cases, functions of gonadotropins in nongonadal tissues have been identified. Several genomic and proteomic approaches including novel mouse genome editing tools are available now. It is anticipated that these and other emerging technologies will be useful to build an integrated network of gonadotropin signaling pathways in various tissues. Undoubtedly, research on gonadotropins will continue to provide new knowledge and allow us transcend from benchside to the bedside.
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21
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Munier M, Grouleff J, Gourdin L, Fauchard M, Chantreau V, Henrion D, Coutant R, Schiøtt B, Chabbert M, Rodien P. In Vitro Effects of the Endocrine Disruptor p,p'-DDT on Human Follitropin Receptor. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:991-9. [PMID: 26895433 PMCID: PMC4937862 DOI: 10.1289/ehp.1510006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 09/25/2015] [Accepted: 02/09/2016] [Indexed: 05/23/2023]
Abstract
BACKGROUND 1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene (p,p'-DDT) is a persistent environmental endocrine disruptor (ED). Several studies have shown an association between p,p'-DDT exposure and reproductive abnormalities. OBJECTIVES To investigate the putative effects of p,p'-DDT on the human follitropin receptor (FSHR) function. METHODS AND RESULTS We used Chinese hamster ovary (CHO) cells stably expressing human FSHR to investigate the impact of p,p'-DDT on FSHR activity and its interaction with the receptor. At a concentration of 5 μM p,p'-DDT increased the maximum response of the FSHR to follitropin by 32 ± 7.45%. However, 5 μM p,p'-DDT decreased the basal activity and did not influence the maximal response of the closely related LH/hCG receptor to human chorionic gonadotropin (hCG). The potentiating effect of p,p'-DDT was specific for the FSHR. Moreover, in cells that did not express FSHR, p,p'-DDT had no effect on cAMP response. Thus, the potentiating effect of p,p'-DDT was dependent on the FSHR. In addition, p,p'-DDT increased the sensitivity of FSHR to hCG and to a low molecular weight agonist of the FSHR, 3-((5methyl)-2-(4-benzyloxy-phenyl)-5-{[2-[3-ethoxy-4-methoxy-phenyl)-ethylcarbamoyl]-methyl}-4-oxo-thiazolidin-3-yl)-benzamide (16a). Basal activity in response to p,p'-DDT and potentiation of the FSHR response to FSH by p,p'-DDT varied among FSHR mutants with altered transmembrane domains (TMDs), consistent with an effect of p,p'-DDT via TMD binding. This finding was corroborated by the results of simultaneously docking p,p'-DDT and 16a into the FSHR transmembrane bundle. CONCLUSION p,p'-DDT acted as a positive allosteric modulator of the FSHR in our experimental model. These findings suggest that G protein-coupled receptors are additional targets of endocrine disruptors. CITATION Munier M, Grouleff J, Gourdin L, Fauchard M, Chantreau V, Henrion D, Coutant R, Schiøtt B, Chabbert M, Rodien P. 2016. In vitro effects of the endocrine disruptor p,p'-DDT on human follitropin receptor. Environ Health Perspect 124:991-999; http://dx.doi.org/10.1289/ehp.1510006.
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Affiliation(s)
- Mathilde Munier
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
- Reference center for rare diseases of hormonal receptivity, Angers, France
| | - Julie Grouleff
- Department of Endocrinology, University Hospital, Angers, France
- Interdisciplinary Nanoscience Center,
| | - Louis Gourdin
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
- Reference center for rare diseases of hormonal receptivity, Angers, France
| | - Mathilde Fauchard
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
| | - Vanessa Chantreau
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
| | - Daniel Henrion
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
| | - Régis Coutant
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
- Reference center for rare diseases of hormonal receptivity, Angers, France
- Department of Endocrinology, University Hospital, Angers, France
| | - Birgit Schiøtt
- Interdisciplinary Nanoscience Center,
- Center for Insoluble Protein Structures, and
- Department of Chemistry, Aarhus University, Aarhus, Denmark
| | - Marie Chabbert
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
| | - Patrice Rodien
- MITOVASC Institute, Angers, France
- UMR CNRS 6214, INSERM 1083, Laboratory of Integrated Neurovascular and Mitochondrial Biology, University of Angers, Angers, France
- Reference center for rare diseases of hormonal receptivity, Angers, France
- Department of Pediatric Endocrinology, University Hospital, Angers, France
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Gonadal development and germ cell tumors in mouse and humans. Semin Cell Dev Biol 2015; 45:114-23. [DOI: 10.1016/j.semcdb.2015.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/01/2015] [Indexed: 12/12/2022]
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23
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Yang QE, Nagaoka SI, Gwost I, Hunt PA, Oatley JM. Inactivation of Retinoblastoma Protein (Rb1) in the Oocyte: Evidence That Dysregulated Follicle Growth Drives Ovarian Teratoma Formation in Mice. PLoS Genet 2015; 11:e1005355. [PMID: 26176933 PMCID: PMC4503754 DOI: 10.1371/journal.pgen.1005355] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 06/12/2015] [Indexed: 02/02/2023] Open
Abstract
The origin of most ovarian tumors is undefined. Here, we report development of a novel mouse model in which conditional inactivation of the tumor suppressor gene Rb1 in oocytes leads to the formation of ovarian teratomas (OTs). While parthenogenetically activated ooctyes are a known source of OT in some mutant mouse models, enhanced parthenogenetic propensity in vitro was not observed for Rb1-deficient oocytes. Further analyses revealed that follicle recruitment and growth is disrupted in ovaries of mice with conditional inactivation of Rb1, leading to abnormal accumulation of secondary/preantral follicles. These findings underpin the concept that miscues between the germ cell and somatic compartments cause premature oocyte activation and the formation of OTs. Furthermore, these results suggest that defects in folliculogenesis and a permissive genetic background are sufficient to drive OT development, even in the absence of enhanced parthenogenetic activation. Thus, we have discovered a novel role of Rb1 in regulating the entry of primordial oocytes into the pool of growing follicles and signaling between the oocyte and granulosa cells during the protracted process of oocyte growth. Our findings, coupled with data from studies of other OT models, suggest that defects in the coordinated regulation between growth of the oocyte and somatic components in follicles are an underlying cause of OT formation.
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Affiliation(s)
- Qi-En Yang
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - So I. Nagaoka
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Ivy Gwost
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Patricia A. Hunt
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Jon M. Oatley
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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Hai L, McGee SR, Rabideau AC, Paquet M, Narayan P. Infertility in Female Mice with a Gain-of-Function Mutation in the Luteinizing Hormone Receptor Is Due to Irregular Estrous Cyclicity, Anovulation, Hormonal Alterations, and Polycystic Ovaries. Biol Reprod 2015; 93:16. [PMID: 26040673 DOI: 10.1095/biolreprod.115.129072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 05/29/2015] [Indexed: 11/01/2022] Open
Abstract
The luteinizing hormone receptor, LHCGR, is essential for fertility in males and females, and genetic mutations in the receptor have been identified that result in developmental and reproductive defects. We have previously generated and characterized a mouse model (KiLHR(D582G)) for familial male-limited precocious puberty caused by an activating mutation in the receptor. We demonstrated that the phenotype of the KiLHR(D582G) male mice is an accurate phenocopy of male patients with activating LHCGR mutations. In this study, we observed that unlike women with activating LHCGR mutations who are normal, female KiLHR(D582G) mice are infertile. Mice exhibit irregular estrous cyclicity, anovulation, and precocious puberty. A temporal study from 2-24 wk of age indicated elevated levels of progesterone, androstenedione, testosterone, and estradiol and upregulation of several steroidogenic enzyme genes. Ovaries of KiLHR(D582G) mice exhibited significant pathology with the development of large hemorrhagic cysts as early as 3 wk of age, extensive stromal cell hyperplasia and hypertrophy with luteinization, numerous atretic follicles, and granulosa cell tumors. Ovulation could not be rescued by the addition of exogenous gonadotropins. The body weights of the KiLHR(D582G) mice were higher than wild-type counterparts, but there was no increase in the body fat composition or metabolic abnormalities such as impaired glucose tolerance and insulin resistance. These studies demonstrate that activating LHCGR mutations do not produce the same phenotype in female mice as in humans and clearly illustrate species differences in the expression and regulation of LHCGR in the ovary, but not in the testis.
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Affiliation(s)
- Lan Hai
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Stacey R McGee
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Amanda C Rabideau
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Marilène Paquet
- Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
| | - Prema Narayan
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
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Mazurkiewicz JE, Herrick-Davis K, Barroso M, Ulloa-Aguirre A, Lindau-Shepard B, Thomas RM, Dias JA. Single-molecule analyses of fully functional fluorescent protein-tagged follitropin receptor reveal homodimerization and specific heterodimerization with lutropin receptor. Biol Reprod 2015; 92:100. [PMID: 25761594 DOI: 10.1095/biolreprod.114.125781] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/02/2015] [Indexed: 01/27/2023] Open
Abstract
We have previously shown that the carboxyl terminus (cT) of human follicle-stimulating hormone (FSH, follitropin) receptor (FSHR) is clipped before insertion into the plasma membrane. Surprisingly, several different constructs of FSHR fluorescent fusion proteins (FSHR-FPs) failed to traffic to the plasma membrane. Subsequently, we discovered that substituting the extreme cT of luteinizing hormone (LH) receptor (LHR) to create an FSHR-LHRcT chimera has no effect on FSHR functionality. Therefore, we used this approach to create an FSHR-LHRcT-FP fusion. We found this chimeric FSHR-LHRcT-FP was expressed in HEK293 cells at levels similar to reported values for FSHR in human granulosa cells, bound FSH with high affinity, and transduced FSH binding to produce cAMP. Quantitative fluorescence resonance energy transfer (FRET) analysis of FSHR-LHRcT-YFP/FSHR-LHRcT-mCherry pairs revealed an average FRET efficiency of 12.9 ± 5.7. Advanced methods in single-molecule analyses were applied in order to ascertain the oligomerization state of the FSHR-LHRcT. Fluorescence correlation spectroscopy coupled with photon-counting histogram analyses demonstrated that the FSHR-LHRcT-FP fusion protein exists as a freely diffusing homodimer in the plasma membrane. A central question is whether LHR could oligomerize with FSHR, because both receptors are coexpressed in differentiated granulosa cells. Indeed, FRET analysis revealed an average FRET efficiency of 14.4 ± 7.5 when the FSHR-LHR cT-mCherry was coexpressed with LHR-YFP. In contrast, coexpression of a 5-HT2cVSV-YFP with FSHR-LHR cT-mCherry showed only 5.6 ± 3.2 average FRET efficiency, a value indistinguishable from the detection limit using intensity-based FRET methods. These data demonstrate that coexpression of FSHR and LHR can lead to heterodimerization, and we hypothesize that it is possible for this to occur during granulosa cell differentiation.
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Affiliation(s)
- Joseph E Mazurkiewicz
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, New York
| | | | - Margarida Barroso
- Center for Cardiovascular Science, Albany Medical College, Albany, New York
| | - Alfredo Ulloa-Aguirre
- Research Support Network, Instituto Nacional de Ciencias Médicas y Nutrición SZ-Universidad Nacional Autónoma de México, México D.F., México
| | - Barbara Lindau-Shepard
- Division of Genetic Disorders, Wadsworth Center, New York State Department of Health, Albany, New York
| | - Richard M Thomas
- Department of Biomedical Sciences, State University of New York at Albany, Albany, New York
| | - James A Dias
- Department of Biomedical Sciences, State University of New York at Albany, Albany, New York
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26
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Jonas KC, Oduwole OO, Peltoketo H, Rulli SB, Huhtaniemi IT. Mouse models of altered gonadotrophin action: insight into male reproductive disorders. Reproduction 2014; 148:R63-70. [DOI: 10.1530/rep-14-0302] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The advent of technologies to genetically manipulate the mouse genome has revolutionised research approaches, providing a unique platform to study the causality of reproductive disorders in vivo. With the relative ease of generating genetically modified (GM) mouse models, the last two decades have yielded multiple loss-of-function and gain-of-function mutation mouse models to explore the role of gonadotrophins and their receptors in reproductive pathologies. This work has provided key insights into the molecular mechanisms underlying reproductive disorders with altered gonadotrophin action, revealing the fundamental roles of these pituitary hormones and their receptors in the hypothalamic–pituitary–gonadal axis. This review will describe GM mouse models of gonadotrophins and their receptors with enhanced or diminished actions, specifically focusing on the male. We will discuss the mechanistic insights gained from these models into male reproductive disorders, and the relationship and understanding provided into male human reproductive disorders originating from altered gonadotrophin action.
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27
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Ulloa-Aguirre A, Reiter E, Bousfield G, Dias JA, Huhtaniemi I. Constitutive activity in gonadotropin receptors. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 70:37-80. [PMID: 24931192 DOI: 10.1016/b978-0-12-417197-8.00002-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Constitutively active mutants (CAMs) of gonadotropin receptors are, in general, rare conditions. Luteinizing hormone-choriogonadotropin receptor (LHCGR) CAMs provoke the dramatic phenotype of familial gonadotropin-independent isosexual male-limited precocious puberty, whereas in females, there is not yet any identified phenotype. Only one isolated follicle-stimulating hormone receptor (FSHR) CAM (Asp567Gly) has so far been detected in a single male patient, besides other FSHR weak CAMs linked to pregnancy-associated ovarian hyperstimulation syndrome or to impaired desensitization and internalization. Several animal models have been developed for studying enhanced gonadotropin action; in addition to unraveling valuable new information about the possible phenotypes of isolated FSHR and LHCGR CAMs in women, the information obtained from these mouse models has served multiple translational goals, including the development of new diagnostic and therapeutic targets as well as the prediction of phenotypes for mutations not yet identified in humans. Mutagenesis and computational studies have shed important information on the physiopathogenic mechanisms leading to constitutive activity of gonadotropin receptors; a common feature in these receptor CAMs is the release of stabilizing interhelical interactions between transmembrane domains (TMDs) 3 and 6 leading to an increase, with respect to the wild-type receptor, in the solvent accessibility at the cytosolic extension of TMDs 3, 5, and 6, which involves the highly conserved Glu/Asp-Arg-Tyr/Trp sequence. In this chapter, we summarize the structural features, functional consequences, and mechanisms that lead to constitutive activation of gonadotropin receptor CAMs and provide information on pharmacological approaches that might potentially modulate gonadotropin receptor CAM function.
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Affiliation(s)
- Alfredo Ulloa-Aguirre
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France; Research Support Network, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán" and Universidad Nacional Autónoma de México, México D.F., Mexico.
| | - Eric Reiter
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France; BIOS Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR7247, Nouzilly, France; Université François Rabelais, Tours, France
| | - George Bousfield
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France; Department of Biological Sciences, Wichita State University, Wichita, Kansas, USA
| | - James A Dias
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France; Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
| | - Ilpo Huhtaniemi
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France; Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom
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28
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Bianco AC, Anderson G, Forrest D, Galton VA, Gereben B, Kim BW, Kopp PA, Liao XH, Obregon MJ, Peeters RP, Refetoff S, Sharlin DS, Simonides WS, Weiss RE, Williams GR. American Thyroid Association Guide to investigating thyroid hormone economy and action in rodent and cell models. Thyroid 2014; 24:88-168. [PMID: 24001133 PMCID: PMC3887458 DOI: 10.1089/thy.2013.0109] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment approaches for patients with thyroid disease. SUMMARY Important clinical practices in use today for the treatment of patients with hypothyroidism, hyperthyroidism, or thyroid cancer are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a series of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings. CONCLUSIONS It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes.
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Affiliation(s)
- Antonio C. Bianco
- Division of Endocrinology, Diabetes and Metabolism, University of Miami Miller School of Medicine, Miami, Florida
| | - Grant Anderson
- Department of Pharmacy Practice and Pharmaceutical Sciences, College of Pharmacy, University of Minnesota Duluth, Duluth, Minnesota
| | - Douglas Forrest
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Valerie Anne Galton
- Department of Physiology and Neurobiology, Dartmouth Medical School, Lebanon, New Hampshire
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Brian W. Kim
- Division of Endocrinology, Diabetes and Metabolism, University of Miami Miller School of Medicine, Miami, Florida
| | - Peter A. Kopp
- Division of Endocrinology, Metabolism, and Molecular Medicine, and Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Xiao Hui Liao
- Section of Adult and Pediatric Endocrinology, Diabetes, and Metabolism, The University of Chicago, Chicago, Illinois
| | - Maria Jesus Obregon
- Institute of Biomedical Investigation (IIB), Spanish National Research Council (CSIC) and Autonomous University of Madrid, Madrid, Spain
| | - Robin P. Peeters
- Division of Endocrinology, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Samuel Refetoff
- Section of Adult and Pediatric Endocrinology, Diabetes, and Metabolism, The University of Chicago, Chicago, Illinois
| | - David S. Sharlin
- Department of Biological Sciences, Minnesota State University, Mankato, Minnesota
| | - Warner S. Simonides
- Laboratory for Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Roy E. Weiss
- Section of Adult and Pediatric Endocrinology, Diabetes, and Metabolism, The University of Chicago, Chicago, Illinois
| | - Graham R. Williams
- Department of Medicine, Imperial College London, Hammersmith Campus, London, United Kingdom
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29
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Prunskaite-Hyyryläinen R, Shan J, Railo A, Heinonen KM, Miinalainen I, Yan W, Shen B, Perreault C, Vainio SJ. Wnt4, a pleiotropic signal for controlling cell polarity, basement membrane integrity, and antimüllerian hormone expression during oocyte maturation in the female follicle. FASEB J 2013; 28:1568-81. [PMID: 24371124 DOI: 10.1096/fj.13-233247] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Wnt4 is a key signal that channels the developmental fate of the indifferent mammalian gonad toward the ovary, but whether Wnt4 has later roles during ovary development remains unknown. To investigate this, we inactivated the Wnt4 gene by crossing Amhr2Cre and doxycycline-inducible Rosa(rtTA)-knock-in Cre mice with mice carrying a floxed Wnt4 allele and used a novel Wnt4(mCherry)-knock-in mouse. In these models, ovarian folliculogenesis was compromised, and female fertility was severely reduced, and Wnt4 deficiency eventually led to premature ovarian failure. These anomalies were associated with cell polarity defects in the follicle. Within the follicle, laminin and type IV collagen assembled ectopic basement membrane-like structures, the cell adherens junction components N-cadherin and β-catenin lost their polarized expression pattern, and expression of the gap junction protein connexin 43 was reduced by ~30% when compared with that of the controls. Besides these changes, expression of antimüllerian hormone (Amh) was inhibited in the absence of Wnt4 signaling in vivo. Consistent with this, Wnt4 signaling up-regulated Amh gene expression in KK1 cells in vitro. Thus, Wnt4 signaling is necessary during maturation of the ovarian follicles, where it coordinates expression of Amh, cell survival, and polarized organization of the follicular cells.
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Affiliation(s)
- Renata Prunskaite-Hyyryläinen
- 1Laboratory of Developmental Biology, Department of Medical Biochemistry and Molecular Biology, University of Oulu and Biocenter Oulu, Aapistie 5, P. O. Box 5000, FIN-90220, Oulu, Finland.
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30
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Fu X, Cheng J, Hou Y, Zhu S. The association between the oocyte pool and aneuploidy: a comparative study of the reproductive potential of young and aged mice. J Assist Reprod Genet 2013; 31:323-31. [PMID: 24362910 DOI: 10.1007/s10815-013-0160-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 12/10/2013] [Indexed: 10/25/2022] Open
Abstract
PURPOSE The present study examined the effect of aging on female reproductive potential. METHODS Six-week-old and 9-month-old CD1 mice were referred to as the 'young' and 'aged' groups, respectively. Oocytes were collected after superovulation, and their viability were compared using parthenogenetic activation. The aneuploidy of the oocytes (MII) was assessed using chromosome spread, and the whole ovarian follicle number was counted using an unbiased stereological method. Serum hormone levels were measured using the radio-immunity method, and the expression of the Cohesin subunit genes in the oocytes (GV) were assessed using RT-PCR. RESULTS The mean number of recovered (25.8 vs. 16.2; P < 0.05) and live oocytes (24.0 vs. 11.73; P <0.01) per head in the young-mice group (6-week-old) was significantly higher than that of the aged group (9-month-old). The aneuploidy rate of the ovulated oocytes in the aged group was significantly higher than that of the young group (36.8% vs. 10%; P < 0.01), and the rate of blastocyst formation in the young group (85.23%) was significantly higher than that of the aged group (81.2%; P <0.05). The number of primordial follicles (the oocyte pool) per ovary in the aged group was significantly decreased compared with the young group (330 ± 33.51 vs. 2079.6 ± 420.70; P < 0.01), and the level of AMH in the aged group was significantly higher than that of the young group (4.66 ± 0.11 ng/ml vs. 4.07 ± 0.18 ng/ml; P < 0.01). CONCLUSIONS We propose that maternal aging significantly reduces the oocyte pool, superovulation efficiency and developmental potential and increases the oocyte aneuploidy rate.
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Affiliation(s)
- Xiangwei Fu
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
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31
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The transcription factor GATA4 is required for follicular development and normal ovarian function. Dev Biol 2013; 381:144-58. [PMID: 23769843 DOI: 10.1016/j.ydbio.2013.06.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 11/20/2022]
Abstract
Sex determination in mammals requires interaction between the transcription factor GATA4 and its cofactor FOG2. We have recently described the function of both proteins in testis development beyond the sex determination stage; their roles in the postnatal ovary, however, remain to be defined. Here, we use gene targeting in mice to determine the requirement of GATA4 and FOG2 in ovarian development and folliculogenesis. The results from this study identify an essential role of the GATA4 protein in the ovarian morphogenetic program. We show that in contrast to the sex determination phase, which relies on the GATA4-FOG2 complex, the subsequent regulation of ovarian differentiation is dependent upon GATA4 but not FOG2. The loss of Gata4 expression within the ovary results in impaired granulosa cell proliferation and theca cell recruitment as well as fewer primordial follicles in the ovarian cortex, causing a failure in follicular development. Preantral follicular atresia is observed within the few follicles that develop despite Gata4 deficiency. The depletion of the follicular pool in GATA4 deficient ovary results in the formation of ovarian cysts and sterility.
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32
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Ulloa-Aguirre A, Dias JA, Bousfield G, Huhtaniemi I, Reiter E. Trafficking of the follitropin receptor. Methods Enzymol 2013; 521:17-45. [PMID: 23351732 DOI: 10.1016/b978-0-12-391862-8.00002-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The follitropin or follicle-stimulating hormone receptor (FSHR) belongs to a highly conserved subfamily of the G protein-coupled receptor (GPCR) superfamily and is mainly expressed in specific cells in the gonads. As any other GPCR, the newly synthesized FSHR has to be correctly folded and processed in order to traffic to the cell surface plasma membrane and interact with its cognate ligand. In this chapter, we describe in detail the conditions and procedures used to study outward trafficking of the FSHR from the endoplasmic reticulum to the plasma membrane. We also describe some methods to analyze phosphorylation, β-arrestin recruitment, internalization, and recycling of this particular receptor, which have proved useful in our hands for dissecting its downward trafficking and fate following agonist stimulation.
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Affiliation(s)
- Alfredo Ulloa-Aguirre
- Studium Consortium for Research and Training in Reproductive Sciences (sCORTS), Tours, France.
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33
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Balakrishnan A, Chaillet JR. Role of the inositol polyphosphate-4-phosphatase type II Inpp4b in the generation of ovarian teratomas. Dev Biol 2012; 373:118-29. [PMID: 23078915 DOI: 10.1016/j.ydbio.2012.10.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/14/2012] [Accepted: 10/09/2012] [Indexed: 10/27/2022]
Abstract
Teratomas are a unique class of tumors composed of ecto-, meso- and endodermal tissues, all foreign to the site of origin. In humans, the most common teratoma is the ovarian teratoma. Not much is known about the molecular and genetic etiologies of these tumors. Female carriers of the Tgkd transgene are highly susceptible to developing teratomas. Ovaries of Tgkd/+ hemizygous female mice exhibit defects in luteinization, with numerous corpora lutea, some of which contain central trapped, fully-grown oocytes. Genetically, Tgkd teratomas originate from mature oocytes that have completed meiosis I, suggesting that Tgkd teratomas originate from these trapped oocytes. The insertion of Tgkd 3' of the Inpp4b gene is associated with decreased expression of Inpp4b and changes in intracellular PI3 Kinase/AKT signaling in follicular granulosa cells. Because Inpp4b is not expressed in fully-grown wild-type or Tgkd oocytes, these findings suggest that hyperactivation of the PI3K/AKT pathway caused by the decrease in INPP4B in granulosa cells promotes an ovarian environment defective in folliculogenesis and conducive to teratoma formation.
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Affiliation(s)
- Ashwini Balakrishnan
- Department of Microbiology and Molecular Genetics, Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, PA 15208, USA
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34
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Menon KMJ, Menon B. Structure, function and regulation of gonadotropin receptors - a perspective. Mol Cell Endocrinol 2012; 356:88-97. [PMID: 22342845 PMCID: PMC3327826 DOI: 10.1016/j.mce.2012.01.021] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 01/13/2012] [Accepted: 01/24/2012] [Indexed: 11/19/2022]
Abstract
Luteinizing hormone receptor and follicle stimulating hormone receptor play a crucial role in female and male reproduction. Significant new information has emerged about the structure, mechanism of activation, and regulation of expression of these receptors. Here we provide an overview of the current information on those aspects with an in-depth discussion of the recent developments in the post-transcriptional mechanism of LH receptor expression mediated by a specific LH receptor mRNA binding protein, designated as LRBP. LRBP was identified by electrophoretic gel mobility shift assay using cytosolic fractions from ovaries in the down regulated state. LRBP was purified, its binding site on LH receptor mRNA was identified and characterized. During ligand-induced down regulation, LRBP expression is increased through the cAMP/PKA and ERK signaling pathway, is translocated to translating ribosomes, binds LH receptor mRNA and forms an untranslatable ribonucleoprotein complex. This complex is then routed to the mRNA degradation machinery resulting in diminished levels of both LHR mRNA and cell surface expression of LH receptor. The studies leading to these conclusions are presented.
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Affiliation(s)
- K M J Menon
- Departments of Obstetrics/Gynecology and Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109-0617, United States.
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35
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Abstract
PURPOSE OF REVIEW To review the current knowledge of genetic variants in the two genes affecting the individual responsiveness to follicle-stimulating hormone (FSH) action-the FSH beta-subunit (FSHB) and the FSH receptor (FSHR), as well as the pharmacogenetic ramifications of the findings. RECENT FINDINGS Four common variants in the FSHB and the FSHR genes were shown to exhibit significant effect on FSH action: linked FSHR variants Thr307Ala and Asn680Ser determining common receptor isoforms, and gene expression affecting polymorphisms FSHR -29G/A and FSHB -211G/T. In women, the FSHR Thr307Ala/Asn680Ser polymorphisms show consistent predictive value for estimating the most optimal recombinant FSH dosage in controlled ovarian hyperstimulation (COH). The same variants exhibit a potential for the pharmacogenetic assessment of the treatment of polycystic ovarian syndrome. The FSHR -29G/A variant was also shown to contribute to ovarian response to COH. Pilot studies have suggested the FSHB -211 TT homozygous oligozoospermic men with genetically determined low concentration of FSH, as potentially the best responders to FSH treatment; furthermore, modulation of this response by FSHR polymorphisms is possible. SUMMARY Genetic variants in FSHB and FSHR exhibit a potential for pharmacogenetic applications in selecting appropriate treatment options (timing and dosage) in male and female conditions requiring or benefiting from FSH therapy.
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Affiliation(s)
- Maris Laan
- Human Molecular Genetics Research Group, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia.
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36
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Walters KA, Allan CM, Handelsman DJ. Rodent models for human polycystic ovary syndrome. Biol Reprod 2012; 86:149, 1-12. [PMID: 22337333 DOI: 10.1095/biolreprod.111.097808] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is the most frequent female endocrine disorder, affecting 5%-10% of women, causing infertility due to dysfunctional follicular maturation and ovulation, distinctive multicystic ovaries and hyperandrogenism, together with metabolic abnormalities including obesity, hyperinsulinism, an increased risk of type 2 diabetes, and cardiovascular disease. The etiology of PCOS is unclear, and decisive clinical studies are limited by ethical and logistic constraints. Consequently treatment is palliative rather than curative and focuses on symptomatic approaches. Hence, a suitable animal model could provide a valuable means with which to study the pathogenesis of the characteristic reproductive and metabolic abnormalities and thereby identify novel and more effective treatments. So far there is no consensus on the best experimental animal model, which should ideally reproduce the key features associated with human PCOS. The prenatally androgenized rhesus monkey displays many characteristics of the human condition, including hyperandrogenism, anovulation, polycystic ovaries, increased adiposity, and insulin insensitivity. However, the high cost of nonhuman primate studies limits the practical utility of these large-animal models. Rodent models, on the other hand, are inexpensive, provide well-characterized and stable genetic backgrounds readily accessible for targeted genetic manipulation, and shorter reproductive life spans and generation times. Recent rodent models display both reproductive and metabolic disturbances associated with human PCOS. This review aimed to evaluate the rodent models reported to identify the advantages and disadvantages of the distinct rodent models used to investigate this complex endocrine disorder.
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Affiliation(s)
- Kirsty A Walters
- Andrology Laboratory, ANZAC Research Institute, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia.
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Abstract
During the last two decades a large number of genetically modified mouse lines with altered gonadotropin action have been generated. These mouse lines fall into three categories: the lack-of-function mice, gain-of-function mice, and the mice generated by breeding the abovementioned lines with other disease model lines. The mouse strains lacking gonadotropin action have elucidated the necessity of the pituitary hormones in pubertal development and function of gonads, and revealed the processes from the original genetic defect to the pathological phenotype such as hypo- or hypergonadotropic hypogonadism. Conversely, the strains of the second group depict consequences of chronic gonadotropin action. The lines vary from those expressing constitutively active receptors and those secreting follicle-stimulating hormone (FSH) with slowly increasing amounts to those producing human choriogonadotropin (hCG), amount of which corresponds to 2000-fold luteinizing hormone (LH)/hCG biological activity. Accordingly, the phenotypes diverge from mild anomalies and enhanced fertility to disrupted gametogenesis, but eventually chronic, enhanced and non-pulsatile action of both FSH and LH leads to female and male infertility and/or hyper- and neoplasias in most of the gonadotropin gain-of-function mice. Elevated gonadotropin levels also alter the function of several extra-gonadal tissues either directly or indirectly via increased sex steroid production. These effects include promotion of tumorigenesis in tissues such as the pituitary, mammary and adrenal glands. Finally, the crossbreedings of the current mouse strains with other disease models are likely to uncover the contribution of gonadotropins in novel biological systems, as exemplified by the recent crossbreed of LHCG receptor deficient mice with Alzheimer disease mice.
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Affiliation(s)
- Hellevi Peltoketo
- Institute of Reproductive and Developmental Biology, Imperial College London, DuCane Road, London, W12 0NN, UK.
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Impact of luteinized unruptured follicles on endometrial receptivity. ACTA ACUST UNITED AC 2011; 31:181. [DOI: 10.1007/s11596-011-0248-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Indexed: 11/26/2022]
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Handelsman DJ. RFD Award Lecture 2010.Hormonal regulation of spermatogenesis: insights from constructing genetic models. Reprod Fertil Dev 2011; 23:507-19. [DOI: 10.1071/rd10308] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Accepted: 12/23/2010] [Indexed: 11/23/2022] Open
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Consequences of genetic manipulations of gonadotrophins and gonadotrophin receptors in mice. ANNALES D'ENDOCRINOLOGIE 2010; 71:170-6. [PMID: 20362970 DOI: 10.1016/j.ando.2010.02.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 02/11/2010] [Accepted: 02/12/2010] [Indexed: 11/23/2022]
Abstract
We have produced over the years several genetically modified mouse models (transgenic [TG], knockout [KO] and knockin [KI]) for the study of normal and aberrant functions of gonadotrophins and their receptors. We summarise in the present review some of our recent findings on these animal models. One is the cascade of extragonadal phenotypes triggered by ovarian hyperstimulation in TG mice overexpressing the human choriongonadotrophin (hCG) beta-subunit and presenting with elevated levels of serum luteinising hormone (LH)/hCG bioactivity. Massively elevated levels of serum progesterone, rather than oestrogens, are responsible for the induction of pituitary prolactinomas and the subsequently elevated prolactin (PRL) levels. Along with normal oestradiol and elevated progesterone levels, the increased concentration of PRL induces lobuloalveolar development of the mammary gland, with ultimate formation of oestrogen and progesterone receptor-negative malignant tumours. Another TG mouse model expressing a constitutively activating mutant form of the follicle-stimulating hormone receptor (FSHR) presents with a strong ovarian phenotype inducing advanced follicular development and depletion, haemorrhagic follicles, teratomas and infertility. A third TG mouse model, coexpressing binding- and signalling-deficient mutants of LHCGR in the KO background for the same receptor (R) gene provided convincing evidence that functional complementation through homo-di/oligomerisation is a physiologically relevant mode of activation of class A G protein-coupled receptors (GPCR). Taken together, genetically modified mouse models provide powerful tools for the elucidation of normal and pathological functions of gonadotrophins and their R.
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