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Sample records for con disgenesia gonadal

  1. [Gonadal dysfunction].

    PubMed

    Tahara, R; Toma, Y; Yanaihara, T

    1997-11-01

    Function of hypothalamic-pituitary-ovarian axis is an essential factor for the maintenance of regular cycles in mature women. The disturbance of function of those organs causes gonadal dysfunction such as anovulation, amenorrhea and menstrual disorders. Therefore, the correct diagnosis for the assessment of CNS and ovarian function is clinically important to treat the patients those who have an menstrual disorders. In this review, the mechanism of normal gonadal cycles and the diagnostic method and the treatment of gonadal dysfunction are described.

  2. [Gonadal function in Turner syndrome].

    PubMed

    Alves, Márcia; Bastos, Margarida; Almeida Santos, Teresa; Carrilho, Francisco

    2013-01-01

    Introdução: A síndrome de Turner caracteriza-se pela ausência, parcial ou total, de um cromossoma X no sexo feminino, sendo uma das cromossomopatias mais frequentes. O diagnóstico é realizado através do cariótipo e as suas manifestações incluem o hipogonadismo primário, antes ou após a puberdade (disgenesia gonadal). O grau de disfunção e a extensão dos defeitos gonadais são variáveis.Objectivos: Pretendeu-se avaliar a clínica, cariótipo, função gonadal e características ecográficas do útero e ovários de mulheres com síndrome de Turner.Material e Métodos: Estudo retrospectivo de doentes com síndrome de Turner, seguidas nos Serviços de Endocrinologia ou Reprodução Humana dos Hospitais da Universidade de Coimbra - Centro Hospitalar e Universitário de Coimbra, E.P.E. Avaliou-se toda a amostra e consideraram-se o grupo 1 (com puberdade e menarca espontânea) e grupo 2 (sem puberdade espontânea). Parâmetros avaliados: idade do estudo inicial, puberdade, cariótipo, FSH, ecografia pélvica inicial e pós-pubertária, celioscopia e indução pubertária. Estudo estatístico: SPSS (20.0).Resultados: Amostra: 79 doentes, 14,7 ± 6,6 anos. Ausência de sinais pubertários em 57,1%, amenorreia primária 67,1% e secundária 6,6%. Cariótipo: monossomia X-37,2%, mosaico-37,2%, alterações estruturais de X-25,6%. Mediana da FSH 59,5mUI/mL. Ecografia inicial: útero normal-34,2%, atrófico-65,8%; ovários normais-21,6%, atróficos-78,4%, com folículos-5,1%. Ecografia pós-pubertária: útero normal-67,9%, atrófico-32,1%; ovários normais-36,4%, atróficos-63,6%. A laparoscopia realizada em 16 (20,3%) doentes confirmou os achados ecográficos. Duas mulheres com puberdade induzida engravidaram: uma espontaneamente, sem evolução; outra pordoação de ovócitos, evolutiva. Grupo 1 (com puberdade e menarca espontânea): 20 (25,3%) doentes, 16,1 ± 8,9 anos. Puberdade na avaliação inicial: M1-22,2%, M2-33,3%, M3-16,7%, M4-16,7%, M5-11,1%. Cari

  3. Relationship of gonadal activity and chemotherapy-induced gonadal damage

    SciTech Connect

    Rivkees, S.A.; Crawford, J.D.

    1988-04-08

    The authors tested the hypothesis that chemotherapy-induced gonadal damage is proportional to the degree of gonadal activity during treatment. Thirty studies that evaluated gonadal function after cyclophosphamide therapy for renal disease or combination chemotherapy for Hodgkin's disease or acute lymphocytic leukemia provided data for analysis. Data were stratified according to sex, illness, chemotherapeutic regimen and dose, and pubertal stage at the time of treatment. Chemotherapy-induced damage was more likely to occur in patients who were treated when sexually mature compared with those who were treated when prepubertal. Males were significantly more frequently affected than females when treated for renal disease of Hodgkin's disease. Chemotherapy-induced damage was also more likely to occur when patients were treated with large doses of alkylating agents. These data suggest that chemotherapy-induced damage is proportional to gonadal activity. Further efforts are needed to test whether induced gonadal quiescence during chemotherapy will reduce the strikingly high incidence of gonadal failure following chemotherapy.

  4. Gonadal dysfunction in systemic diseases.

    PubMed

    Karagiannis, Asterios; Harsoulis, Faidon

    2005-04-01

    Gonadal function is significantly affected in many acute and chronic systemic diseases. As the function of the testes and the ovaries is determined by the integrity of the hypothalamic-pituitary-gonadal axis, it is obvious that a systemic disease may affect one or more levels of the axis in such a manner that the gonadal dysfunction may have various clinical and laboratory manifestations. In this brief review, the most common disturbances seen in the main systemic diseases will be discussed.

  5. Exercise and gonadal function.

    PubMed

    Elias, A N; Wilson, A F

    1993-10-01

    Exercise is associated with release of a number of pituitary and hypothalamic hormones and a decline in the concentration of luteinizing hormone (LH). Follicle stimulating hormone (FSH) is generally not influenced by exercise. Serum inhibin concentrations, which are reciprocally influenced by serum FSH concentrations, are increased in some animals but are unchanged after acute exercise in human males. Teleologically, the decline in gonadotrophic hormone (LH) secretion after exercise may be geared to enhance individual survival over species propagation in times of stress, analogous to the postulated 'fight or flight' reaction. The decrease in gonadotrophic hormone (LH) secretion is believed to be due to changes in gonadotrophin releasing hormone (GnRH) pulse frequency and amplitude, particularly in women, who often develop amenorrhoea. Males have less dramatic changes in their hypothalamic-pituitary-gonadal axis, although a significant decrease in serum testosterone in physically conditioned males can usually be demonstrated. In this update possible mechanisms for the decline in gonadotrophin secretion with exercise are briefly discussed.

  6. Studies of gonadal sex differentiation

    PubMed Central

    Makiyan, Zograb

    2016-01-01

    ABSTRACT Gonadal differentiation has a determinative influence on sex development in human embryos. Disorders of sexual development (DSD) have been associated with persistent embryonal differentiation stages. Between 1998 and 2015, 139 female patients with various (DSD) underwent operations at the Scientific Center of Obstetrics, Gynaecology and Perynatology in Moscow, Russia. Clinical investigations included karyotyping, ultrasound imaging, hormonal measurement and investigations of gonadal morphology. The male characteristics in the embryo are imposed by testicular hormones. When these are absent or inactive, the fetus may be arrested at between developmental stages, or stay on indifferent stage and become phenotypically female. A systematic analysis of gonadal morphology in DSD patients and a literature review revealed some controversies and led us to formulate a new hypothesis about sex differentiation. Proliferation of the mesonephric system (tubules and corpuscles) in the gonads stimulates the masculinization of gonads to testis. Sustentacular Sertoli cells of the testes are derived from mesonephric excretory tubules, while interstitial Leydig cells are derived from the original mesenchyme of the mesonephros. According of the new hypothesis, the original mesonephric cells (tubules and corpuscles) potentially persist in the ovarian parenchyma. In female gonads, some mesonephric excretory tubules regress and lose the tubular structure, but form ovarian theca interna and externa, becoming analogous to the sustentacular Sertoli cells in the testis. The ovarian interstitial Leydig cells are derived from intertubal mesenchyme of the mesonephros, similar to what occurs in male gonads (testis). Surprisingly, the leading determinative factor in sexual differentiation of the gonads is the mesonephros, represented by the embryonic urinary system. PMID:26950283

  7. Stem Cells in Mammalian Gonads.

    PubMed

    Wu, Ji; Ding, Xinbao; Wang, Jian

    2016-01-01

    Stem cells have great value in clinical application because of their ability to self-renew and their potential to differentiate into many different cell types. Mammalian gonads, including testes for males and ovaries for females, are composed of germline and somatic cells. In male mammals, spermatogonial stem cells maintain spermatogenesis which occurs continuously in adult testis. Likewise, a growing body of evidence demonstrated that female germline stem cells could be found in mammalian ovaries. Meanwhile, prior studies have shown that somatic stem cells exist in both testes and ovaries. In this chapter, we focus on mammalian gonad stem cells and discuss their characteristics as well as differentiation potentials.

  8. Gonadal dysgenesis in del (18p) syndrome

    SciTech Connect

    Telvi, L.; Ion, A.; Fouquet, F.

    1995-07-17

    We report on a girl with syndromal gonadal dysgenesis and a de novo del (18p). Genetic factors controlling gonadal development are located not only on the X chromosome, but also on autosomes. The present case suggests that one of these genes is situated on 18p. We conclude that patients with del (18p) syndrome should be evaluated for gonadal dysgenesis. 16 refs., 3 figs.

  9. Mutation of Gonadal soma-derived factor induces medaka XY gonads to undergo ovarian development.

    PubMed

    Imai, Takuto; Saino, Kentaro; Matsuda, Masaru

    2015-11-01

    Gonochoristic species have a bipotential gonad that develops into a testis or an ovary. In species whose sex is determined by a genetic factor, the expression of a sex-determining gene is the first cue that directs the development of a bipotential gonad. Subsequent expression of downstream genes induces the gonad to develop into a testis or an ovary. The TGF-ß family member Gonadal soma-derived factor (Gsdf) is thought to be an important gene for gonadal development in teleost fish, and it is expressed at higher levels in the testis than in the ovary from early to mature stages. However, there is little functional information about the gene. In this study, we targeted the Gsdf coding region in the medaka fish Oryzias latipes using transcription activator-like effector nucleases (TALENs) and studied the phenotypes of the Gsdf mutant medaka. Although normal and heterozygous XY gonads developed into a testis, all XY gonads with a homozygous mutation in Gsdf developed into an ovary at early developmental stages. However, two-thirds of Gsdf mutant XY gonads developed into testes in the adult stages. These results demonstrate that although a gonad can develop into a complete testis in the absence of Gsdf, Gsdf function is critical for directing the bipotential gonad at early developmental stages. Therefore, Gsdf is an endogenous inducer of testicular development similar to a master sex-determining gene.

  10. Gonadal sex chromosome complement in individuals with sex chromosomal and/or gonadal disorders

    SciTech Connect

    Bridge, J.A.; Sanger, W.G.; Seemayer, T.

    1994-09-01

    Gonadal abnormalities are characteristically seen in patients with sex chromosomal aneuploidy. Morphologically these abnormalities can be variable and are hypothesized to be dependent on the sex chromosomal consititution of the gonad (independent of the chromosomal complement of other tissues, such as peripheral blood lymphocytes). In this study, the gonadal sex chromosome complement was evaluated for potential mosaicism and correlated with the histopathology from 5 patients with known sex chromosomal and/or gonadal disorders. FISH techniques using X and Y chromosome specific probes were performed on nuclei extracted from paraffin embedded tissue. Gonadal tissue obtained from case 1 (a true hemaphroditic newborn) consisted of ovotestes and epididymis (left side) and ovary with fallopian tube (right side). Cytogenetic and FISH studies performed on blood, ovotestes and ovary revealed an XX complement. Cytogenetic analysis of blood from case 2, a 4-year-old with suspected Turner syndrome revealed 45,X/46,X,del(Y)(q11.21). FISH analysis of the resected gonads (histologically = immature testes) confirmed an X/XY mosaic complement. Histologically, the gonadal tissue was testicular. Severe autolysis prohibited successful analysis in the 2 remaining cases. In summary, molecular cytogenetic evaluation of gonadal tissue from individuals with sex chromosomal and/or gonadal disorders did not reveal tissue-specific anomalies which could account for differences observed pathologically.

  11. Methods for the Study of Gonadal Development.

    PubMed

    Piprek, Rafal P

    2016-01-01

    Current knowledge on gonadal development and sex determination is the product of many decades of research involving a variety of scientific methods from different biological disciplines such as histology, genetics, biochemistry, and molecular biology. The earliest embryological investigations, followed by the invention of microscopy and staining methods, were based on histological examinations. The most robust development of histological staining techniques occurred in the second half of the nineteenth century and resulted in structural descriptions of gonadogenesis. These first studies on gonadal development were conducted on domesticated animals; however, currently the mouse is the most extensively studied species. The next key point in the study of gonadogenesis was the advancement of methods allowing for the in vitro culture of fetal gonads. For instance, this led to the description of the origin of cell lines forming the gonads. Protein detection using antibodies and immunolabeling methods and the use of reporter genes were also invaluable for developmental studies, enabling the visualization of the formation of gonadal structure. Recently, genetic and molecular biology techniques, especially gene expression analysis, have revolutionized studies on gonadogenesis and have provided insight into the molecular mechanisms that govern this process. The successive invention of new methods is reflected in the progress of research on gonadal development. PMID:27300186

  12. Thyroid-gonad relationship in chronic schizophrenia.

    PubMed

    Parshad, O; Uppal, A

    1989-06-01

    The effects of the severity of psychiatric illnesses on thyroid function and their relationship to serum testosterone levels were studied in 38 men of African origin, suffering from chronic schizophrenia. Significantly lower levels of serum T4, T3, FT4I and testosterone in acutely psychotic patients indicated decreased thyroid-gonadal activity. Higher serum T4 and FT4I and lower serum TSH, testosterone and cortisol levels were observed in patients whose illnesses were in remission. Levels of both FT4I and testosterone in clinically stable patients, however, were not significantly different in comparison to controls, suggesting recovery from the illness. No significant differences either in thyroid or gonadal hormones were observed between patients exhibiting depression or elated affects; among disorganized, catatonic, paranoid and undifferentiated types; and among patients treated with different psychotropic drugs. The possible mechanisms involved in such thyroid-gonad relationship are discussed.

  13. Gonadal ecdysteroidogenesis in arthropoda: occurrence and regulation.

    PubMed

    Brown, Mark R; Sieglaff, Douglas H; Rees, Huw H

    2009-01-01

    Ecdysteroids are multifunctional hormones in male and female arthropods and are stored in oocytes for use during embryogenesis. Ecdysteroid biosynthesis and its hormonal regulation are demonstrated for insect gonads, but not for the gonads of other arthropods. The Y-organ in the cephalothorax of crustaceans and the integument of ticks are sources of secreted ecdysteroids in adults, as in earlier stages, but the tissue source is not known for adults in many arthropod groups. Ecdysteroid metabolism occurs in several tissues of adult arthropods. This review summarizes the evidence for ecdysteroid biosynthesis by gonads and its metabolism in adult arthropods and considers the apparent uniqueness of ecdysteroid hormones in arthropods, given the predominance of vertebrate-type steroids in sister invertebrate groups and vertebrates.

  14. Exogenous estradiol alters gonadal growth and timing of temperature sex determination in gonads of sea turtle.

    PubMed

    Díaz-Hernández, Verónica; Marmolejo-Valencia, Alejandro; Merchant-Larios, Horacio

    2015-12-01

    Temperature sex determining species offer a model for investigating how environmental cues become integrated to the regulation of patterning genes and growth, among bipotential gonads. Manipulation of steroid hormones has revealed the important role of aromatase in the regulation of the estrogen levels involved in temperature-dependent sex determination. Estradiol treatment counteracts the effect of male-promoting temperature, but the resulting ovarian developmental pattern differs from that manifested with the female-promoting temperature. Hypoplastic gonads have been reported among estradiol-treated turtles; however the estradiol effect on gonadal size has not been examined. Here we focused on the sea turtle Lepidochelys olivacea, which develops hypoplastic gonads with estradiol treatment. We studied the effect of estradiol on cell proliferation and on candidate genes involved in ovarian pattern. We found this effect is organ specific, causing a dramatic reduction in gonadal cell proliferation during the temperature-sensitive period. Although the incipient gonads resembled tiny ovaries, remodeling of the medullary cords and down-regulation of testicular factor Sox9 were considerably delayed. Contrastingly, with ovarian promoting temperature as a cue, exogenous estradiol induced the up-regulation of the ovary factor FoxL2, prior to the expression of aromatase. The strong expression of estrogen receptor alpha at the time of treatment suggests that it mediates estradiol effects. Overall results indicate that estradiol levels required for gonadal growth and to establish the female genetic network are delicately regulated by temperature.

  15. Exogenous estradiol alters gonadal growth and timing of temperature sex determination in gonads of sea turtle.

    PubMed

    Díaz-Hernández, Verónica; Marmolejo-Valencia, Alejandro; Merchant-Larios, Horacio

    2015-12-01

    Temperature sex determining species offer a model for investigating how environmental cues become integrated to the regulation of patterning genes and growth, among bipotential gonads. Manipulation of steroid hormones has revealed the important role of aromatase in the regulation of the estrogen levels involved in temperature-dependent sex determination. Estradiol treatment counteracts the effect of male-promoting temperature, but the resulting ovarian developmental pattern differs from that manifested with the female-promoting temperature. Hypoplastic gonads have been reported among estradiol-treated turtles; however the estradiol effect on gonadal size has not been examined. Here we focused on the sea turtle Lepidochelys olivacea, which develops hypoplastic gonads with estradiol treatment. We studied the effect of estradiol on cell proliferation and on candidate genes involved in ovarian pattern. We found this effect is organ specific, causing a dramatic reduction in gonadal cell proliferation during the temperature-sensitive period. Although the incipient gonads resembled tiny ovaries, remodeling of the medullary cords and down-regulation of testicular factor Sox9 were considerably delayed. Contrastingly, with ovarian promoting temperature as a cue, exogenous estradiol induced the up-regulation of the ovary factor FoxL2, prior to the expression of aromatase. The strong expression of estrogen receptor alpha at the time of treatment suggests that it mediates estradiol effects. Overall results indicate that estradiol levels required for gonadal growth and to establish the female genetic network are delicately regulated by temperature. PMID:26465360

  16. Stem cell potential of the mammalian gonad

    PubMed Central

    Liu, Chia-Feng; Barsoum, Ivraym; Gupta, Rupesh; Hofmann, Marie-Claude; Yao, Humphrey Hung-Chang

    2010-01-01

    Stem cells have enormous potential for therapeutic application because of their ability to self-renew and differentiate into different cell types. Gonads, which consist of somatic cells and germ cells, are the only organs capable of transmitting genetic materials to the offspring. Germ-line stem cells and somatic stem cells have been found in the testis; however, the presence of stem cells in the ovary remains controversial. In this review, we discuss studies focusing on whether stem cell properties are present in the different cell types of male and female gonads and their implications on stem cell research. PMID:19482665

  17. [46 XY gonadal dysgenesis and dysgerminoma (author's transl)].

    PubMed

    Ausín, J; Cavallé, L; Márquez, M; González-Merlo, J

    1980-01-01

    A patient with gonadal dysgenesis, cariotype 46 XY and female biotype is presented. The histological study confirmed the presence of a dysgerminoma in the left gonad. The features of the cases are discussed.

  18. Gonadal vein tumor thrombosis due to renal cell carcinoma.

    PubMed

    Haghighatkhah, Hamidreza; Karimi, Mohammad Ali; Taheri, Morteza Sanei

    2015-01-01

    Renal cell carcinoma (RCC) had a tendency to extend into the renal vein and inferior vena cava, while extension into the gonadal vein has been rarely reported. Gonadal vein tumor thrombosis appears as an enhancing filling defect within the dilated gonadal vein anterior to the psoas muscle and shows an enhancement pattern identical to that of the original tumor. The possibility of gonadal vein thrombosis should be kept in mind when looking at an imaging study of patients with RCC.

  19. Laser capture microdissection of gonads from juvenile zebrafish

    PubMed Central

    2009-01-01

    Background Investigating gonadal gene expression is important in attempting to elucidate the molecular mechanism of sex determination and differentiation in the model species zebrafish. However, the small size of juvenile zebrafish and correspondingly their gonads complicates this type of investigation. Furthermore, the lack of a genetic sex marker in juvenile zebrafish prevents pooling gonads from several individuals. The aim of this study was to establish a method to isolate the gonads from individual juvenile zebrafish allowing future investigations of gonadal gene expression during sex determination and differentiation. Methods The laser capture microdissection technique enables isolation of specific cells and tissues and thereby removes the noise of gene expression from other cells or tissues in the gene expression profile. A protocol developed for laser microdissection of human gonocytes was adjusted and optimised to isolate juvenile zebrafish gonads. Results The juvenile zebrafish gonad is not morphologically distinguishable when using dehydrated cryosections on membrane slides and a specific staining method is necessary to identify the gonads. The protocol setup in this study allows staining, identification, isolation and subsequent RNA purification and amplification of gonads from individual juvenile zebrafish thereby enabling gonadal gene expression profiling. Conclusion The study presents a protocol for isolation of individual juvenile zebrafish gonads, which will enable future investigations of gonadal gene expression during the critical period of sex differentiation. Furthermore, the presented staining method is applicable to other species as it is directed towards alkaline phosphatase that is expressed in gonocytes and embryonic stem cells, which is conserved among vertebrate species. PMID:19747405

  20. Interactions between the gonadal steroids and the immune system.

    PubMed

    Grossman, C J

    1985-01-18

    The immune system is regulated by the gonadal steroids estrogen, androgen, and progesterone, but the circulating levels of these steroids can also be affected by immune system function. Such interactions appear to be mediated through the hypothalamic-pituitary-gonadal-thymic axis and depend on pituitary luteinizing hormone released by thymic factors under the control of the gonadal steroids.

  1. Gonadal hormones in schizophrenia and mood disorders.

    PubMed

    Ozcan, M Erkan; Banoglu, R

    2003-08-01

    There are gender-related differences in the prevalence, course and treatment response characteristics of schizophrenia and mood disorders. Gonadal steroids exert potent effects on mood, cognition and behavior, and there is little doubt that androgens are crucial for differentiating to each gender. Serum level of total testosterone, free testosterone, estradiol and sex hormone binding globulin was measured in 69 medication-free men with either schizophrenia (n=29) or bipolar I disorder, manic episode (n=18) or major depressive disorder (n=22). There was a statistically significant difference in free testosterone level between mania and schizophrenia groups (p<0.05). The higher free testosterone level in the mania group compared to the schizophrenia group found in this study supports further investigation of a potential difference in the hypothalamic-pituitary-gonadal axis between patients with schizophrenia and bipolar I disorder, manic.

  2. Melatonin and hypothalamic-pituitary-gonadal axis.

    PubMed

    Shi, L; Li, N; Bo, L; Xu, Z

    2013-01-01

    Melatonin (N-acetyl-5-methoxy-tryptamine), a principal product of the pineal gland, is produced mainly during the dark phase of the circadian cycle. This hormone plays a crucial role in the regulation of circadian and seasonal changes in various aspects of physiology and neuroendocrine functions. In mammals, melatonin can influence sexual maturation and reproductive functions via activation of its receptors and binding sites in the hypothalamic-pituitary-gonadal (HPG) axis. This review summarizes current knowledge of melatonin on the hypothalamus, pituitary gland, and gonads. We also review recent progress in clinical applications of melatonin or potentials of using melatonin, as a reducer of oxidative stress, to improve reproductive functions for the diseases such as women infertility.

  3. [Sexual and gonadal dysfunction in adrenal disorders].

    PubMed

    Horiba, N

    1997-11-01

    Among various diseases of the adrenals, major disorders that cause sexual and gonadal disturbances are congenital adrenal hyperplasia(CAH) and Cushing's syndrome, and the others include virilizing or feminizing adrenocortical tumors. CAH was reviewed based on the recent advances in molecular genetics. The most striking discovery was steroidogenic acute regulatory protein, mutations of which produce lipoid adrenal hyperplasia that was previously attributed to P-450scc deficiency. Reversible amenorrhea or impotence is found in patients with Cushing's syndrome. Low plasma estrogen and testosterone levels are associated with female and male patients, respectively. Elevated adrenal androgen accounts for mild virilization in female patients with ACTH-dependent subtypes. The sites of action at which hypercortisolemia suppresses the hypothalamic-pituitary-gonadal axis were discussed.

  4. Obesity and gonadal function of women.

    PubMed

    Diamanti-Kandarakis, Evanthia; Kandarakis, Helen A

    2004-08-01

    Excessive visceral adiposity is associated with metabolic and reproductive abnormalities. Adipose tissue is an active endocrine gland and participates in multiple mechanisms in the reproductive function of women. The nature of the complex interaction of obesity with the female reproductive function remains a challenge. Several links have been implicated in the gonadal dysfunction of obese women, like insulin resistance and hyperinsulinemia, via which ovarian androgen production is stimulated resulting in hyperandrogenemia, increased peripheral aromatization of androgens to estrogens, altered gonadotrophin secretion, decreased sex hormone binding globulin, decreased GH and IGFBPs, increased leptin levels and altered neuroregulation of the hypothalamic-pituitary-gonadal axis. The impact of obesity in these mechanisms and their influence on female reproductive function are discussed in this article.

  5. Gonadal transcriptome analysis of wild contaminated female European eels during artificial gonad maturation.

    PubMed

    Baillon, Lucie; Oses, Jennifer; Pierron, Fabien; Bureau du Colombier, Sarah; Caron, Antoine; Normandeau, Eric; Lambert, Patrick; Couture, Patrice; Labadie, Pierre; Budzinski, Hélène; Dufour, Sylvie; Bernatchez, Louis; Baudrimont, Magalie

    2015-11-01

    Since the early 1980s, the population of European eels (Anguilla anguilla) has dramatically declined. Nowadays, the European eel is listed on the red list of threatened species (IUCN Red List) and is considered as critically endangered of extinction. Pollution is one of the putative causes for the collapse of this species. Among their possible effects, contaminants gradually accumulated in eels during their somatic growth phase (yellow eel stage) would be remobilized during their reproductive migration leading to potential toxic events in gonads. The aim of this study was to investigate the effects of organic and inorganic contaminants on the gonad development of wild female silver eels. Female silver eels from two sites with differing contamination levels were artificially matured. Transcriptomic analyses by means of a 1000 candidate gene cDNA microarray were performed on gonads after 11weeks of maturation to get insight into the mechanisms of toxicity of contaminants. The transcription levels of several genes, that were associated to the gonadosomatic index (GSI), were involved in mitotic cell division but also in gametogenesis. Genes associated to contaminants were mainly involved in the mechanisms of protection against oxidative stress, in DNA repair, in the purinergic signaling pathway and in steroidogenesis, suggesting an impairment of gonad development in eels from the polluted site. This was in agreement with the fact that eels from the reference site showed a higher gonad growth in comparison to contaminated fish. PMID:26159298

  6. Neuropeptides in the Gonads: From Evolution to Pharmacology

    PubMed Central

    McGuire, Nicolette L.; Bentley, George E.

    2010-01-01

    Vertebrate gonads are the sites of synthesis and binding of many peptides that were initially classified as neuropeptides. These gonadal neuropeptide systems are neither well understood in isolation, nor in their interactions with other neuropeptide systems. Further, our knowledge of the control of these gonadal neuropeptides by peripheral hormones that bind to the gonads, and which themselves are under regulation by true neuropeptide systems from the hypothalamus, is relatively meager. This review discusses the existence of a variety of neuropeptides and their receptors which have been discovered in vertebrate gonads, and the possible way in which such systems could have evolved. We then focus on two key neuropeptides for regulation of the hypothalamo-pituitary-gonadal axis: gonadotropin-releasing hormone (GnRH) and gonadotropin-inhibitory hormone (GnIH). Comparative studies have provided us with a degree of understanding as to how a gonadal GnRH system might have evolved, and they have been responsible for the discovery of GnIH and its gonadal counterpart. We attempt to highlight what is known about these two key gonadal neuropeptides, how their actions differ from their hypothalamic counterparts, and how we might learn from comparative studies of them and other gonadal neuropeptides in terms of pharmacology, reproductive physiology and evolutionary biology. PMID:21607065

  7. The occurrence of gonadal dysgenesis in association with monozygotic twinning.

    PubMed Central

    Karp, L; Bryant, J I; Tagatz, G; Giblett, E; Fialkow, P J

    1975-01-01

    A case is presented of a monozygotic twin pair, discordant for phenotypic sex, in which the female member showed gonadal dysgenesis and chromosomal mosaicism. Review of the pertinent literature reveals that in monozygotic twin pairs, phenotypic and karyotypic concordance is the usual occurrence for Down's and Klinefelter's syndromes, whereas discordance often accompanies gonadal dysgenesis. Mosaicism is a frequent concomitant of gonadal dysgenesis in monozygotic twins. Our case strengthens the probability of a real association between mosaicism and monozygotic twinning in gonadal dysgenesis. Images PMID:1121022

  8. [Function and expression of transcription factors implicated in gonadal differentiation].

    PubMed

    Morohashi, K

    1998-07-01

    Several transcription factors such as SRY, DAX-1, Ad4BP/SF-1, WT-1 and SOX -9, have been revealed to be implicated in gonadal development by analyzing the genetic disorders of human and the gene disrupted mice. All of these transcription factors are expressed in the early stage of the gonadal development and the expression profiles during the gonadal development are clearly different between the two sexes. Functions of the transcription factors are discussed by referring genes under the control of these factors. Effects of endocrine disruptants on the expression of Ad4BP/SF-1 in the fetal gonads was also discussed. PMID:9702047

  9. Effects of centrifugation on gonadal and adrenocortical steroids in rats

    NASA Technical Reports Server (NTRS)

    Kakihana, R.; Butte, J. C.

    1980-01-01

    Many endocrine systems are sensitive to external changes in the environment. Both the pituitary adrenal and pituitary gonadal systems are affected by stress including centrifugation stress. The effect of centrifugation on the pituitary gonadal and pituitary adrenocortical systems was examined by measuring the gonadal and adrenal steroids in the plasma and brain following different duration and intensity of centrifugation stress in rats. Two studies were completed and the results are presented. The second study was carried out to describe the developmental changes of brain, plasma and testicular testosterone and dihydrotestosterone in Sprague Dawley rats so that the effect of centrifugation stress on the pituitary gonadal syatem could be better evaluated in future studies.

  10. Migratory mechanisms of chick primordial germ cells toward gonadal anlage.

    PubMed

    Kuwana, T; Rogulska, T

    1999-07-01

    After appearing at the germinal crescent region, chick primordial germ cells (PGCs) migrate toward the presumptive gonads (pG) till stage 19 (Hamburger and Hamilton, 1951). This study seeks to elucidate the roles of passive and active factors in the PGC-migration, physical trapping of circulating PGCs by the capillary network and PGC attraction by chemotactic factor from presumptive gonads. Firstly, latex beads/pollens (the same size or larger than PGCs) were injected into the embryonic bloodstream at stage 13-19 (when PGCs are in the migrating and settlement phase to the presumptive gonad) in ovo in order to determine whether the PGCs passively reach pG. Most of such particles accumulated in the head region (60%), whereas the remainder did the same in the gonadal region (23% at the peak) at stage 16 when both the head and gonadal regions are rich in capillary plexus. After 3 days, most particles in the gonadal region were located at the angles of dorsal mesentery near the developing gonads where many extra-gonadal PGCs had been located, and a few particles were detected close to the gonad. These results suggest that one of the mechanisms of PGC-migration to the developing gonads is an autonomous trapping of PGCs by the capillary network quite close to the germinal epithelium (GE) and passive translocation by morphogenetic movement. Secondly, the attraction for PGCs by the gonadal anlage proper was examined in ovo using chick and quail embryos. Grafts of quail gonadal anlage containing gonadal epithelium and neighbouring mesenchymal tissue were excised from the quail embryo at stages 12 to 16 (staging by Zacchei, 1961). With the aims of eliminating the influence of surrounding tissue, the quail graft was ectopically transplanted into the posterior to the optic vesicle of 8 to 17 somite chick embryo from the point of a posterior region to the auditory vesicle by a fine tungsten needle under the illumination by the method of Hara (1971). Then the region posterior to

  11. Chronic stress, visceral obesity and gonadal dysfunction.

    PubMed

    Kyrou, Ioannis; Tsigos, Constantine

    2008-01-01

    Chronic stress represents a prolonged state of dyshomeostasis caused by intense and frequently imposed stressors. Obesity constitutes a chronic dysmetabolic state, leading progressively to a spectrum of metabolic complications, such as diabetes, dyslipidemia, hypertension and cardiovascular disease. Alpha growing body of evidence supports the existence of significant interactions between stress and obesity, with chronic stress promoting weight gain, and consequently excessive fat accumulation especially visceral, all these factors contributing to the development of a chronic stressful state. Maintaining body homeostasis is a prerequisite for normal reproductive function, which is vital for the survival of the species and an important process of natural selection. Under chronic stress, reproductive function is suspended and disrupted due to central and peripheral actions of hormones, adipokines and pro-inflammatory cytokines that inhibit the activity of the hypothalamic-pituitary gonadal (HPG) axis at various levels. Clinical and experimental data link both obesity and chronic stress to dysregulation of the gonadal axis, via independent and synergistic mechanisms, which may chronically lead to reproductive dysfunction and reduced fertility.

  12. Genetic regulation of mammalian gonad development.

    PubMed

    Eggers, Stefanie; Ohnesorg, Thomas; Sinclair, Andrew

    2014-11-01

    Sex-specific gonadal development starts with formation of the bipotential gonad, which then differentiates into either a mature testis or an ovary. This process is dependent on activation of either the testis-specific or the ovary-specific pathway while the opposite pathway is continuously repressed. A network of transcription factors tightly regulates initiation and maintenance of these distinct pathways; disruption of these networks can lead to disorders of sex development in humans and male-to-female or female-to-male sex reversal in mice. Sry is the Y-linked master switch that is both required and sufficient to drive the testis-determining pathway. Another key component of the testis pathway is Sox9, which acts immediately downstream of Sry. In contrast to the testis pathway, no single sex-determining factor has been identified in the ovary pathway; however, multiple genes, such as Foxl2, Rspo1, Ctnnb1, and Wnt4, seem to work synergistically and in parallel to ensure proper ovary development. Our understanding of the regulatory networks that underpin testis and ovary development has grown substantially over the past two decades.

  13. Dissecting the Role of Hedgehog Pathway in Murine Gonadal Development

    ERIC Educational Resources Information Center

    Barsoum, Ivraym Boshra

    2009-01-01

    Hedgehog (Hh) signaling pathway is one of the universal pathways involved in animal development. This dissertation focuses on Hh role in the mammalian gonad development, which is a central part of mammalian sexual development and identity. The central dogma of mammalian sex development is that genetic sex determines the gonadal sex, which in turn…

  14. Pure gonadal dysgenesis (46 XX type) with a familial pattern.

    PubMed

    Kohmanaee, Shahin; Dalili, Setila; Rad, Afagh Hassanzadeh

    2015-01-01

    46, XX gonadal dysgenesis without the phenotype of Turner's syndrome is described as "pure". Although, previous investigations obtained that commonly gonadal dysgenesis did not cause breast development as a result of low levels of circulating estradiol. However, in this study, we aimed to report a familial pure gonadal dysgenesis with and without normal secondary sexual characteristics. In this study, we reported three siblings with pure gonadal dysgenesis with and without normal secondary sexual characteristics. The elder two sisters had a normal female phenotype and the youngest had amenorrhea with no breast development (B1) and pubic hair. In addition, it seems that the absence of pubic hair occurred due to delayed constitutional puberty. According to results, it seems that clinicians should consider different presentations for pure gonadal dysgenesis with familial pattern.

  15. Characterization of early gonadal development in smallmouth bass (Micropterus dolomieu) and effects of ethinyl estradiol on gonadal differentiation

    EPA Science Inventory

    Teleosts vary widely in patterns of gonadal sex differentiation, which might lead to differences in how gonadal development is affected by the presence of estrogenic compounds. This makes it difficult to apply our knowledge of model species such as medaka and fathead minnow to o...

  16. Angiotensin II receptors in the gonads

    SciTech Connect

    Aguilera, G.; Millan, M.A.; Harwood, J.P.

    1989-05-01

    The presence of components of the renin-angiotensin system in ovaries and testes suggests that angiotensin II (AII) is involved in gonadal function, and thus we sought to characterize receptors for AII in rat and primate gonads. In the testes, autoradiographic studies showed receptors in the interstitium in all species. In rat interstitial cells fractionated by Percoll gradient, AII receptors coincided with hCG receptors indicating that AII receptors are located on the Leydig cells. In Leydig cells and membranes from rat and rhesus monkey prepuberal testes, AII receptors were specific for AII analogues and of high affinity (Kd=nM). During development, AII receptor content in rat testes decreases with age parallel to a fall in the ratio of interstitial to tubular tissue. In the ovary, the distribution of AII receptors was dependent on the stage of development, being high in the germinal epithelium and stromal tissue between five and 15 days, and becoming localized in secondary follicles in 20-and 40-day-old rats. No binding was found in primordial or primary follicles. In rhesus monkey ovary, AII receptors were higher in stromal tissue and lower in granulosa and luteal cells of the follicles. Characterization of the binding in rat and monkey ovarian membranes showed a single class of sites with a Kd in the nmol/L range and specificity similar to that of the adrenal glomerulosa and testicular AII receptors. Receptors for AII were also present in membrane fractions from PMSG/hCG primed rat ovaries. Infusion of AII (25 ng/min) or captopril (1.4 micrograms/min) during the PMSG/hCG induction period had no effect on ovarian weight or AII receptor concentration in the ovaries.

  17. Ontogeny of pituitary-gonadal interactions: current advances and controversies.

    PubMed

    Huhtaniemi, I T; Warren, D W

    1990-01-01

    The different compartments of the fetal hypothalamic-pituitary-gonadal axis, the hypothalamus, anterior pituitary, and gonads, probably start their embryonic development independently, and become fully interactive as the last link o f their maturation. The developing hypothalamic-pituitary-gonadal axis offers a good model for studies on the mechanisms of regulation of fetal hormonal systems. It is evident that fetal hormonal functions are not the same as those of the adult on a smaller scale, but that there are fundamental differences between the fetus and adult in basic features of the mechanisms o f reproductive hormone action.

  18. Psychological stress and the function of male gonads.

    PubMed

    Jóźków, Paweł; Mędraś, Marek

    2012-01-01

    Stress is generally a natural phenomenon that affects behaviour, physiological processes, and neuroendocrine, neurochemical, neurological and immune responses. Many somatic and mental disorders are thought to result from chronic stress. Stress-induced gonadal dysfunction is not restricted to humans, but is observed in all higher animals. Stress-induced gonadal dysfunction comprises disturbances of the hypothalamic-pituitary-gonadal axis and of spermatogenesis. Various stressors induce changes in the secretion of neurotransmitters and hormones, such as CRH, ADH, beta-endorphins, somatostatin, VIP, PRL, GH, TSH, dopamine, serotonin, neuropeptide Y, melatonin, ACTH, glucocorticosteroids, catecholamines and androgens. In acute stress, testicular function is principally modified by cytokines and fluctuating concentrations of gonadotropins, while in chronic stress, hypogonadotropic hypogonadism and disruption of spermatogenesis of varying severity, including spermatogenetic arrest, are observed. In spite of the decades-long interest in the relationships between psychological stress and the function of male gonads, many questions in this area remain unanswered.

  19. The genetics of XX gonadal dysgenesis

    SciTech Connect

    Aittomaeki, K. )

    1994-05-01

    In a nationwide population-based study of women born between 1950 and 1976, 75 patients with XX gonadal dysgenesis (XXGD) were identified in Finland. Patients were ascertained through hospital records and the registers of chromosome laboratories. In one family 4 daughters were affected; in six families 2 daughters were affected; and 57 cases were isolated. In one additional family the two affected females were in successive generations. Population records were utilized to trace ancestors of patients back to the beginning of the 19th century, in most cases. Consanguinity was detected in 8 (12%) of 66 families. When females only are considered, the segregation analyses yield a proportion of .23 affected. The relatively large number of affected individuals identified (incidence 1 in 8,300 live-born girls) implies a high gene frequency in the Finnish population. The geographic distribution was highly uneven, with most families originating in the sparsely populated north-central part of Finland. These findings support the existence of an autosomal recessive (XXGD) gene (locus designation [open quotes]ODG1[close quotes]) that is highly enriched in Finland. The multiplex families already identified will make it possible to map the ODG1 gene by a random search for linkage by using polymorphic markers. Linkage-disequilibrium analysis in the sporadic patients will then be used to test for genetic homogeneity versus heterogeneity. 27 refs., 3 figs.

  20. [Genes related with male gonadal morphogenesis in mammals].

    PubMed

    Wu, Jie; Wang, Feng

    2008-04-01

    Gene expressions are sex-specific in the sex development of mammals. Different genes express in different phases and tend to change with the time. The functions of some genes, such as SRY, SOX9, SOX8, DAX1, and FGF9, have already been defined in male gonadal morphogenesis. This paper presents a review of the genes involved in the formation of the male gonad in mammals. PMID:18481432

  1. Variations of Gonadal Veins: Embryological Prospective and Clinical Significance

    PubMed Central

    Gupta, Raman; Aggarwal, Navita

    2015-01-01

    Introduction: An adequate knowledge of anomalies of gonadal veins will help the radiologists and surgeons in recognition and protection of these veins which play major roles in thermo-regulation that is essential for the efficient functioning of testis on which the survival of the human species depends. Aim: The aim of this work is to present an analysis of the anatomical variations of gonadal veins. An effort has also been made to explicate the possible embryological model of development of such variants and to present the variable clinical aspects concerning them. Materials and Methods: Gonadal veins in 60 dissection room cadavers were examined for variations from the classic anatomic description. Result: In the present study, out of 60 cases, male: female ratio was 2:1(40:20) in which no variation was found in ovarian veins. In the 18 (45%) cases, testicular veins showed variations which consist of duplication and atypical drainage. Discussion: Variations of drainage of gonadal vein are due to error of embryological development in venous shift and alteration in anastomotic channel of post-cardinal, supra-cardinal and sub cardinal veins. Conclusion: The gonadal veins present numeric variations as well as variations in its site of drainage, which attributed to the various pathological conditions as varicocele and pelvic congestion syndrome, leading to infertility in patients. Hence, in -depth knowledge of these developmental anomalies of gonadal veins is important. PMID:25859438

  2. [SF-1, a key player in adrenal and gonadal differentiation: implications in gonadal dysgenesis and primary ovarian insufficiency].

    PubMed

    Martinerie, L; Bouvattier, C; Lombes, M

    2009-09-01

    Steroidogenic factor 1 (SF-1) gene, identified by Keith Parker in 1992, encodes for an orphan nuclear receptor, NR5A1, whose expression is detected during fetal life in adrenal and gonadal steroidogenic tissues, but also in the developing hypothalamus and in pituitary gonadotropic cells. SF-1 knock-out mouse models exhibit complete adrenal and gonadal agenesis. Human mutations of this transcription factor, were initially associated with primary adrenal failure and male gonadal dysgenesis with various degrees of under androgenization. More recently, identification of novel SF-1 mutations responsible for isolated 46, XY gonadal dysgenesis or 46, XX primary ovarian insufficiency, underscores its central role in the control and maintenance of adrenal and reproductive functions. A better understanding in the regulatory mechanisms of SF-1 signaling pathway, will open new avenues for diagnostic and therapeutic managements of sex differentiation disorders and infertilities.

  3. Metal levels in the liver, muscle, gill, intestine, and gonad of Lake Van fish (Chalcalburnus tarichi) with abnormal gonad.

    PubMed

    Oğuz, Ahmet R; Yeltekin, Aslı

    2014-06-01

    Recently, an increasing number of studies have shown that Lake Van--the biggest soda lake in the world--is polluted due to an increasing population. Studies have shown abnormalities in the Lake Van fish (Chalcalburnus tarichi), the sole fish species that inhabits the lake. Unlike the vitellogenic and mature oocytes in normal gonads, abnormal gonads show large amounts of connective tissue and young oocytes. In this study, metal levels (nickel [Ni], copper [Cu], cobalt [Co], iron [Fe], zinc [Zn], cadmium [Cd], lead [Pb], and manganese [Mn]) in the muscle, liver, gill, intestine, and gonad of Lake Van fish with normal and abnormal gonads were assessed. Further, the metal contents in the wastewater from the wastewater treatment facility situated near Lake Van in Van City were assessed. All the metal levels, except that of Zn, were high in the Lake Van environment (P<0.05). The highest metal content in the tissues was for Fe, while the lowest level was for Co. The Pb level was found to be very high in both fish groups. Cd was not found in the tissues of both fish groups. The levels of Fe, Cu, Pb, and Mn were not significant in the tissues of both normal and abnormal fish groups. Zn level was significantly high in the livers and gonads of fish with abnormal gonads, and Co level was significantly high only in the livers (P<0.05). Consequently, high levels of Zn in the liver and gonads and high levels of Co in the liver may be factors causing the abnormal gonads in the Lake Van fish.

  4. Cell-Specific mRNA Profiling of the Caenorhabditis elegans Somatic Gonadal Precursor Cells Identifies Suites of Sex-Biased and Gonad-Enriched Transcripts

    PubMed Central

    Kroetz, Mary B.; Zarkower, David

    2015-01-01

    The Caenorhabditis elegans somatic gonad differs greatly between the two sexes in its pattern of cell divisions, migration, and differentiation. Despite decades of study, the genetic pathways directing early gonadal development and establishing sexual dimorphism in the gonad remain largely unknown. To help define the genetic networks that regulate gonadal development, we employed cell-specific RNA-seq. We identified transcripts present in the somatic gonadal precursor cells and their daughter cells of each sex at the onset of sexual differentiation. We identified several hundred gonad-enriched transcripts, including the majority of known regulators of early gonadal development, and transgenic reporter analysis confirmed the effectiveness of this approach. Before the division of the somatic gonad precursors, few sex-biased gonadal transcripts were detectable; less than 6 hr later, after their division, we identified more than 250 sex-biased transcripts, of which about a third were enriched in the somatic gonad compared to the whole animal. This indicates that a robust sex-biased developmental program, some of it gonad-specific, initiates in the somatic gonadal precursor cells around the time of their first division. About 10% of male-biased transcripts had orthologs with male-biased expression in the early mouse gonad, suggesting possible conservation of gonad sex differentiation. Cell-specific analysis also identified approximately 70 previously unannotated mRNA isoforms that are enriched in the somatic gonad. Our data illustrate the power of cell-specific transcriptome analysis and suggest that early sex differentiation in the gonad is controlled by a relatively small suite of differentially expressed genes, even after dimorphism has become apparent. PMID:26497144

  5. Extra-gonadal sites of estrogen biosynthesis and function.

    PubMed

    Barakat, Radwa; Oakley, Oliver; Kim, Heehyen; Jin, Jooyoung; Ko, CheMyong Jay

    2016-09-01

    Estrogens are the key hormones regulating the development and function of reproductive organs in all vertebrates. Recent evidence indicates that estrogens play important roles in the immune system, cancer development, and other critical biological processes related to human well-being. Obviously, the gonads (ovary and testis) are the primary sites of estrogen synthesis, but estrogens synthesized in extra- gonadal sites play an equally important role in controlling biological activities. Understanding non-gonadal sites of estrogen synthesis and function is crucial and will lead to therapeutic interventions targeting estrogen signaling in disease prevention and treatment. Developing a rationale targeting strategy remains challenging because knowledge of extra-gonadal biosynthesis of estrogens, and the mechanism by which estrogen activity is exerted, is very limited. In this review, we will summarize recent discoveries of extra-gonadal sites of estrogen biosynthesis and their local functions and discuss the significance of the most recent novel discovery of intestinal estrogen biosynthesis. [BMB Reports 2016; 49(9): 488-496]. PMID:27530684

  6. Migratory ability of gonadal germ cells (GGCs) isolated from Ciconia boyciana and Geronticus eremita embryos into the gonad of developing chicken embryos

    PubMed Central

    NAKAJIMA, Yuki; FUKUDA, Haruka; ONUMA, Manabu; MURATA, Koichi; UEDA, Miya; SUNAGA, Emi; SHIRAISHI, Toshirou; TAJIMA, Atsushi

    2016-01-01

    We conducted experiments to evaluate the ability of gonadal germ cells (GGCs), isolated from the embryonic gonads of Ciconia boyciana or Geronticus eremita, to migrate into the gonads of developing chicken embryos. Fluorescently labeled GGCs, isolated by the PBS (−) method, were transferred into the dorsal aorta of 2-day-old chicken embryos. Five days after transfer, fluorescent GGCs were detected in the gonads of recipient embryos. Our results indicate that GGCs from Ciconia boyciana and Geronticus eremita are capable of migrating into the gonads of developing chicken embryos. PMID:26922915

  7. Sources and function of neuronal signalling molecules in the gonads.

    PubMed

    Mayerhofer, A; Frungieri, M B; Bulling, A; Fritz, S

    1999-01-01

    While the hypothalamic-pituitary-gonadal axis is crucial for the function of the gonads, non-endocrine regulatory influences are exerted by other factors within the gonads. Among these factors are neurotransmitters, such as catecholamines. Several types of receptors for catecholamines exist in the gonads on vascular or endocrine cells. Their activation can alter blood flow, steroidogenesis and gene expression, depending on the target cells. Recently a neuronal-like cell type expressing catecholamine-biosynthetic enzymes and neuronal proteins was identified in testis and ovary of human and non-human primates. Together with the well-known sympathetic innervation, this gonadal nervous system may serve as a source of catecholamines. Dopamine is present in the follicular fluid. Oocytes, while not able to perform de novo synthesis of catecholamines, were shown to utilize dopamine to produce norepinephrine. This catecholamine then acts on beta-adrenoreceptors of follicular cells to increase cAMP. Oocytes may thus indirectly via dopamine and cAMP be able to control their own meiotic arrest. In addition, neurotransmitters may also be synthesized in other, non-neuronal ovarian cells. Thus, cultured human granulosa-luteal cells possess the acetylcholine synthesizing enzyme and the acetylcholine-specific vesicular transporter protein. These cells also express muscarinic-receptors (M1), which are linked to the mobilization of intracellular calcium and cell proliferation. This suggests involvement of the acetylcholine system in follicular growth and in the periovulatory events. In neurons, neurotransmitters alter the properties of the neuronal cell membrane. If this is the case in endocrine cells of the gonads is not yet clear, but the recent identification of voltage-activated potassium and sodium channels in human luteinized granulosa-luteal cells raises this question and opens a door to a new area of investigation.

  8. Estrogens and gonadal function in schizophrenia and related psychoses.

    PubMed

    Riecher-Rössler, Anita; Kulkarni, Jayashri

    2011-01-01

    Recent research has increasingly pointed to the importance of estrogens and the hypothalamic-pituitary-gonadal axis in schizophrenia. Specifically, there is mounting evidence from clinical, epidemiological, and basic research that estradiol, the main component of estrogens, exerts protective effects in schizophrenia and related psychoses. Possible modes of action of this hormone in the brain have been suggested, and clinical intervention studies have reported the first positive results. Furthermore, there are an increasing number of reports on gonadal dysfunction and states of estrogen deficiency in women with schizophrenia. These findings could have important implications for clinicians and researchers alike.

  9. [Hypothalamic-hypophyseal-gonadal axis in chronic alcoholic patients].

    PubMed

    Rallo, R; Fermoso, J; Ramos, F; González-Calvo, V; Marañón, Y A

    1979-01-01

    Eleven male chronic alcoholics without cirrhosis but with clinical features of alcoholism were studied. Ten healthy men of similar age served as controls. After suppressing hormone (FSH), luteinizing hormone (LH), 17-beta-oestradiol (E2) and testosterone were determined in basal conditions and after administration of clomiphene citrate in each case. Basal levels of FSH, LH and E2 were higher and the testosterone level lower in the alcoholic group. After stimulation, there was no difference in gonadal hormone levels between both groups, suggesting a normal hypothalamic-pituitary axis with an adequate gonadal response.

  10. Social regulation of the brain-pituitary-gonadal axis.

    PubMed

    Francis, R C; Soma, K; Fernald, R D

    1993-08-15

    Reproduction in vertebrates is regulated by the hypothalamic-pituitary-gonadal axis via neural and hormonal feedback. This axis is also subject to exogenous influences, particularly social signals. In the African cichlid fish Haplochromis burtoni, gonadal development in males is socially regulated. A small fraction of the males, which are brightly colored, maintain territories and aggressively dominate inconspicuously colored nonterritorial males. Here we show through manipulation of the social and endocrine environment that changes in social status and gonadal state are accompanied by soma size changes in a population of gonadotropin-releasing hormone-containing neurons in the ventral forebrain. In territorial males, these cells are significantly larger than in nonterritorial males. When an animal switches from being territorial to nonterritorial through a change in social situation, these cells shrink; in animals that change from nonterritorial to territorial status, the cells enlarge. These gonadotropin-releasing hormone-containing cells project to the pituitary and are ultimately responsible for regulating gonadal growth. This mechanism of socially induced cell size change provides the potential for relatively quick adaptive changes in the neuron-endocrine system without nerve cell addition or death. Since the structure of this regulatory axis is conserved among all vertebrates, other species with socially modulated reproductive physiology may exhibit a similar form of physiological regulation.

  11. Gonadal development in mammals at the cellular and molecular levels.

    PubMed

    Mackay, S

    2000-01-01

    In mammals, although sex is determined chromosomally, gonads in both sexes begin development as similar structures. Until recently it was widely held that female development constituted a "default" pathway of development, which would occur in the absence of a testis-determining gene. This master gene on the Y chromosome, SRY in the human and Sry in the mouse, is thought to act in a cell-autonomous fashion to determine that cells in the gonadal somatic population develop as pre-Sertoli cells. Triggering of somatic cell differentiation along the Sertoli cell pathway is therefore a key event; it was thought that further steps in gonadal differentiation would follow in a developmental cascade. In the absence of Sertoli cells, the lack of anti-Mullerian hormone would allow development of the female Mullerian duct and absence of Leydig cells would prevent maintenance of the Wolffian duct. Recent findings that female signals not only maintain the Mullerian duct and repress the Wolffian duct but also suppress the development of Leydig cells and maintain meiotic germ cells, together with the finding that an X-linked gene is required for ovarian development and must be silenced in the male, have shown that the female default pathway model is an oversimplification. Morphological steps in gonadal differentiation can be correlated with emerging evidence of molecular mechanisms; growth factors, cell adhesion, and signaling molecules interact together, often acting within short time windows via reciprocal control relationships.

  12. AMPK: a master energy regulator for gonadal function.

    PubMed

    Bertoldo, Michael J; Faure, Melanie; Dupont, Joëlle; Froment, Pascal

    2015-01-01

    From C. elegans to mammals (including humans), nutrition and energy metabolism significantly influence reproduction. At the cellular level, some detectors of energy status indicate whether energy reserves are abundant (obesity), or poor (diet restriction). One of these detectors is AMPK (5' AMP-activated protein kinase), a protein kinase activated by ATP deficiency but also by several natural substances such as polyphenols or synthetic molecules like metformin, used in the treatment of insulin resistance. AMPK is expressed in muscle and liver, but also in the ovary and testis. This review focuses on the main effects of AMPK identified in gonadal cells. We describe the role of AMPK in gonadal steroidogenesis, in proliferation and survival of somatic gonadal cells and in the maturation of oocytes or spermatozoa. We discuss also the role of AMPK in germ and somatic cell interactions within the cumulus-oocyte complex and in the blood testis barrier. Finally, the interface in the gonad between AMPK and modification of metabolism is reported and discussion about the role of AMPK on fertility, in regards to the treatment of infertility associated with insulin resistance (male obesity, polycystic ovary syndrome). PMID:26236179

  13. See-Thru-Gonad zebrafish line: developmental and functional validation.

    PubMed

    Presslauer, Christopher; Bizuayehu, Teshome Tilahun; Razmi, Komeil; Fernandes, Jorge M O; Babiak, Igor

    2016-11-01

    Zebrafish are an important model species in developmental biology. However, their potential in reproductive biology research has yet to be realized. In this study, we established See-Thru-Gonad zebrafish, a transparent line with fluorescently labeled germ cells visible throughout the life cycle, validated its gonadal development features, and demonstrated its applicability by performing a targeted gene knockdown experiment using vivo-morpholinos (VMOs). To establish the line, we crossed the zf45Tg and mitfa(w2/w2); mpv17(b18/b18) zebrafish lines. We documented the in vivo visibility of the germline-specific fluorescent signal throughout development, from gametes through embryonic and juvenile stages up to sexual maturity, and validated gonadal development with histology. We performed targeted gene knockdown of the microRNA (miRNA) miR-92a-3p through injection of VMOs directly to maturing ovaries. After the treatment, zebrafish were bred naturally. Embryos from miR-92a-3p knockdown ovaries had a significant reduction in relative miR-92a-3p expression and a higher percentage of developmental arrest at the 1-cell stage as compared with 5-base mismatch-treated controls. The experiment demonstrates that See-Thru-Gonad line can be successfully used for vertical transmission of the effects of targeted gene knockdown in ovaries into their offspring. PMID:27655215

  14. AMPK: a master energy regulator for gonadal function

    PubMed Central

    Bertoldo, Michael J.; Faure, Melanie; Dupont, Joëlle; Froment, Pascal

    2015-01-01

    From C. elegans to mammals (including humans), nutrition and energy metabolism significantly influence reproduction. At the cellular level, some detectors of energy status indicate whether energy reserves are abundant (obesity), or poor (diet restriction). One of these detectors is AMPK (5′ AMP-activated protein kinase), a protein kinase activated by ATP deficiency but also by several natural substances such as polyphenols or synthetic molecules like metformin, used in the treatment of insulin resistance. AMPK is expressed in muscle and liver, but also in the ovary and testis. This review focuses on the main effects of AMPK identified in gonadal cells. We describe the role of AMPK in gonadal steroidogenesis, in proliferation and survival of somatic gonadal cells and in the maturation of oocytes or spermatozoa. We discuss also the role of AMPK in germ and somatic cell interactions within the cumulus-oocyte complex and in the blood testis barrier. Finally, the interface in the gonad between AMPK and modification of metabolism is reported and discussion about the role of AMPK on fertility, in regards to the treatment of infertility associated with insulin resistance (male obesity, polycystic ovary syndrome). PMID:26236179

  15. Gonad establishment during asexual reproduction in the annelid Pristina leidyi.

    PubMed

    Özpolat, B Duygu; Bely, Alexandra E

    2015-09-01

    Animals that can reproduce by both asexual agametic reproduction and sexual reproduction must transmit or re-establish their germ line post-embryonically. Although such a dual reproductive mode has evolved repeatedly among animals, how asexually produced individuals establish their germ line remains poorly understood in most groups. We investigated germ line development in the annelid Pristina leidyi, a species that typically reproduces asexually by paratomic fission, intercalating a new tail and head in the middle of the body followed by splitting. We found that in fissioning individuals, gonads occur in anterior segments in the anterior-most individual as well as in new heads forming within fission zones. Homologs of the germ line/multipotency genes piwi, vasa, and nanos are expressed in the gonads, as well as in proliferative tissues including the posterior growth zone, fission zone, and regeneration blastema. In fissioning animals, certain cells on the ventral nerve cord express a homolog of piwi, are abundant near fission zones, and sometimes make contact with gonads. Such cells are typically undetectable near the blastema and posterior growth zone. Time-lapse imaging provides direct evidence that cells on the ventral nerve cord migrate preferentially towards fission zones. Our findings indicate that gonads form routinely in fissioning individuals, that a population of piwi-positive cells on the ventral nerve cord is associated with fission and gonads, and that cells resembling these piwi-positive cells migrate along the ventral nerve cord. We suggest that the piwi-positive ventral cells are germ cells that transmit the germ line across asexually produced individuals via migration along the ventral nerve cord. PMID:26134407

  16. Gonad establishment during asexual reproduction in the annelid Pristina leidyi.

    PubMed

    Özpolat, B Duygu; Bely, Alexandra E

    2015-09-01

    Animals that can reproduce by both asexual agametic reproduction and sexual reproduction must transmit or re-establish their germ line post-embryonically. Although such a dual reproductive mode has evolved repeatedly among animals, how asexually produced individuals establish their germ line remains poorly understood in most groups. We investigated germ line development in the annelid Pristina leidyi, a species that typically reproduces asexually by paratomic fission, intercalating a new tail and head in the middle of the body followed by splitting. We found that in fissioning individuals, gonads occur in anterior segments in the anterior-most individual as well as in new heads forming within fission zones. Homologs of the germ line/multipotency genes piwi, vasa, and nanos are expressed in the gonads, as well as in proliferative tissues including the posterior growth zone, fission zone, and regeneration blastema. In fissioning animals, certain cells on the ventral nerve cord express a homolog of piwi, are abundant near fission zones, and sometimes make contact with gonads. Such cells are typically undetectable near the blastema and posterior growth zone. Time-lapse imaging provides direct evidence that cells on the ventral nerve cord migrate preferentially towards fission zones. Our findings indicate that gonads form routinely in fissioning individuals, that a population of piwi-positive cells on the ventral nerve cord is associated with fission and gonads, and that cells resembling these piwi-positive cells migrate along the ventral nerve cord. We suggest that the piwi-positive ventral cells are germ cells that transmit the germ line across asexually produced individuals via migration along the ventral nerve cord.

  17. Dynamic testing in the evaluation of male gonadal function.

    PubMed

    De Martino, M U; Pastore, R; Caprio, M; Frajese, G; Fabbri, A

    2003-01-01

    The maturation and physiologic functions of male sexual apparatus are under the control of the hypothalamic-pituitary-gonadal (HPG) axis. The determination of gonadotropins and testosterone as secretory products of pituitary and gonads, respectively, represents the first step in the evaluation of male sexual function and the diagnosis of disorders in male reproductive axis. However, there are several clinical situations that require a dynamic evaluation of this system and the measurement of basal gonadotropins and testosterone must be combined with specific dynamic tests. These mainly consist in GnRH stimulation, which evaluates the endocrine reserve capacity of the pituitary, and human chorionic gonadotropin (hCG) stimulation, which is used in the assessment of Leydig cells activity. The paper illustrates the technical aspects, the normal/pathological responses and the role of these two tests in assessing the male HPG axis in respect to different clinical diagnostic queries.

  18. Dielectric properties of porcine glands, gonads and body fluids.

    PubMed

    Peyman, A; Gabriel, C

    2012-10-01

    Dielectric properties of porcine glandular tissues and gonads (in vivo) and body fluids (in vitro) have been obtained in the frequency range of 50 MHz to 20 GHz. The experimental data were fitted to a two term Cole-Cole expression. The data presented complement the available dielectric properties of tissues in the literature and can be used in numerical simulations of the exposure of people to electromagnetic fields.

  19. Kallmann syndrome 1 gene is expressed in the marsupial gonad.

    PubMed

    Hu, Yanqiu; Yu, Hongshi; Shaw, Geoff; Pask, Andrew J; Renfree, Marilyn B

    2011-03-01

    Kallmann syndrome is characterized by hypogonadotrophic hypogonadism and anosmia. The syndrome can be caused by mutations in several genes, but the X-linked form is caused by mutation in the Kallmann syndrome 1 (KAL1). KAL1 plays a critical role in gonadotropin-releasing hormone (GnRH) neuronal migration that is essential for the normal development of the hypothalamic-pituitary-gonadal axis. Interestingly, KAL1 appears to be missing from the rodent X, and no orthologue has been detected as yet. We investigated KAL1 during development and in adults of an Australian marsupial, the tammar wallaby, Macropus eugenii. Marsupial KAL1 maps to an autosome within a group of genes that was added as a block to the X chromosome in eutherian evolution. KAL1 expression was widespread in embryonic and adult tissues. In the adult testis, tammar KAL1 mRNA and protein were detected in the germ cells at specific stages of differentiation. In the adult testis, the protein encoded by KAL1, anosmin-1, was restricted to the round spermatids and elongated spermatids. In the adult ovary, anosmin-1 was not only detected in the oocytes but was also localized in the granulosa cells throughout folliculogenesis. This is the first examination of KAL1 mRNA and protein localization in adult mammalian gonads. The protein localization suggests that KAL1 participates in gametogenesis not only through the development of the hypothalamic-pituitary-gonadal axis by activation of GnRH neuronal migration, but also directly within the gonads themselves. Because KAL1 is autosomal in marsupials but is X-linked in eutherians, its conserved involvement in gametogenesis supports the hypothesis that reproduction-related genes were actively recruited to the eutherian X chromosome.

  20. Physiology of the Hypothalamic Pituitary Gonadal Axis in the Male.

    PubMed

    Corradi, Patricia Freitas; Corradi, Renato B; Greene, Loren Wissner

    2016-05-01

    Testosterone synthesis and male fertility are the results of the perfect coordination of the hypothalamic-pituitary-gonadal axis. A negative feedback finely controls the secretion of hormones at the 3 levels. Congenital or acquired disturbance at any level leads to an impairment of reproductive function and the clinical syndrome of hypogonadism. In some cases, this condition is reversible. Once the diagnosis is made, testosterone replacement therapy is the standard therapy; however, novel therapies may improve spermatogenesis while elevating testosterone levels.

  1. Kallmann syndrome 1 gene is expressed in the marsupial gonad.

    PubMed

    Hu, Yanqiu; Yu, Hongshi; Shaw, Geoff; Pask, Andrew J; Renfree, Marilyn B

    2011-03-01

    Kallmann syndrome is characterized by hypogonadotrophic hypogonadism and anosmia. The syndrome can be caused by mutations in several genes, but the X-linked form is caused by mutation in the Kallmann syndrome 1 (KAL1). KAL1 plays a critical role in gonadotropin-releasing hormone (GnRH) neuronal migration that is essential for the normal development of the hypothalamic-pituitary-gonadal axis. Interestingly, KAL1 appears to be missing from the rodent X, and no orthologue has been detected as yet. We investigated KAL1 during development and in adults of an Australian marsupial, the tammar wallaby, Macropus eugenii. Marsupial KAL1 maps to an autosome within a group of genes that was added as a block to the X chromosome in eutherian evolution. KAL1 expression was widespread in embryonic and adult tissues. In the adult testis, tammar KAL1 mRNA and protein were detected in the germ cells at specific stages of differentiation. In the adult testis, the protein encoded by KAL1, anosmin-1, was restricted to the round spermatids and elongated spermatids. In the adult ovary, anosmin-1 was not only detected in the oocytes but was also localized in the granulosa cells throughout folliculogenesis. This is the first examination of KAL1 mRNA and protein localization in adult mammalian gonads. The protein localization suggests that KAL1 participates in gametogenesis not only through the development of the hypothalamic-pituitary-gonadal axis by activation of GnRH neuronal migration, but also directly within the gonads themselves. Because KAL1 is autosomal in marsupials but is X-linked in eutherians, its conserved involvement in gametogenesis supports the hypothesis that reproduction-related genes were actively recruited to the eutherian X chromosome. PMID:21123819

  2. GPCRs Direct Germline Development and Somatic Gonad Function in Planarians.

    PubMed

    Saberi, Amir; Jamal, Ayana; Beets, Isabel; Schoofs, Liliane; Newmark, Phillip A

    2016-05-01

    Planarians display remarkable plasticity in maintenance of their germline, with the ability to develop or dismantle reproductive tissues in response to systemic and environmental cues. Here, we investigated the role of G protein-coupled receptors (GPCRs) in this dynamic germline regulation. By genome-enabled receptor mining, we identified 566 putative planarian GPCRs and classified them into conserved and phylum-specific subfamilies. We performed a functional screen to identify NPYR-1 as the cognate receptor for NPY-8, a neuropeptide required for sexual maturation and germ cell differentiation. Similar to NPY-8, knockdown of this receptor results in loss of differentiated germ cells and sexual maturity. NPYR-1 is expressed in neuroendocrine cells of the central nervous system and can be activated specifically by NPY-8 in cell-based assays. Additionally, we screened the complement of GPCRs with expression enriched in sexually reproducing planarians, and identified an orphan chemoreceptor family member, ophis, that controls differentiation of germline stem cells (GSCs). ophis is expressed in somatic cells of male and female gonads, as well as in accessory reproductive tissues. We have previously shown that somatic gonadal cells are required for male GSC specification and maintenance in planarians. However, ophis is not essential for GSC specification or maintenance and, therefore, defines a secondary role for planarian gonadal niche cells in promoting GSC differentiation. Our studies uncover the complement of planarian GPCRs and reveal previously unappreciated roles for these receptors in systemic and local (i.e., niche) regulation of germ cell development.

  3. GPCRs Direct Germline Development and Somatic Gonad Function in Planarians

    PubMed Central

    Saberi, Amir; Beets, Isabel; Schoofs, Liliane; Newmark, Phillip A.

    2016-01-01

    Planarians display remarkable plasticity in maintenance of their germline, with the ability to develop or dismantle reproductive tissues in response to systemic and environmental cues. Here, we investigated the role of G protein-coupled receptors (GPCRs) in this dynamic germline regulation. By genome-enabled receptor mining, we identified 566 putative planarian GPCRs and classified them into conserved and phylum-specific subfamilies. We performed a functional screen to identify NPYR-1 as the cognate receptor for NPY-8, a neuropeptide required for sexual maturation and germ cell differentiation. Similar to NPY-8, knockdown of this receptor results in loss of differentiated germ cells and sexual maturity. NPYR-1 is expressed in neuroendocrine cells of the central nervous system and can be activated specifically by NPY-8 in cell-based assays. Additionally, we screened the complement of GPCRs with expression enriched in sexually reproducing planarians, and identified an orphan chemoreceptor family member, ophis, that controls differentiation of germline stem cells (GSCs). ophis is expressed in somatic cells of male and female gonads, as well as in accessory reproductive tissues. We have previously shown that somatic gonadal cells are required for male GSC specification and maintenance in planarians. However, ophis is not essential for GSC specification or maintenance and, therefore, defines a secondary role for planarian gonadal niche cells in promoting GSC differentiation. Our studies uncover the complement of planarian GPCRs and reveal previously unappreciated roles for these receptors in systemic and local (i.e., niche) regulation of germ cell development. PMID:27163480

  4. GPCRs Direct Germline Development and Somatic Gonad Function in Planarians.

    PubMed

    Saberi, Amir; Jamal, Ayana; Beets, Isabel; Schoofs, Liliane; Newmark, Phillip A

    2016-05-01

    Planarians display remarkable plasticity in maintenance of their germline, with the ability to develop or dismantle reproductive tissues in response to systemic and environmental cues. Here, we investigated the role of G protein-coupled receptors (GPCRs) in this dynamic germline regulation. By genome-enabled receptor mining, we identified 566 putative planarian GPCRs and classified them into conserved and phylum-specific subfamilies. We performed a functional screen to identify NPYR-1 as the cognate receptor for NPY-8, a neuropeptide required for sexual maturation and germ cell differentiation. Similar to NPY-8, knockdown of this receptor results in loss of differentiated germ cells and sexual maturity. NPYR-1 is expressed in neuroendocrine cells of the central nervous system and can be activated specifically by NPY-8 in cell-based assays. Additionally, we screened the complement of GPCRs with expression enriched in sexually reproducing planarians, and identified an orphan chemoreceptor family member, ophis, that controls differentiation of germline stem cells (GSCs). ophis is expressed in somatic cells of male and female gonads, as well as in accessory reproductive tissues. We have previously shown that somatic gonadal cells are required for male GSC specification and maintenance in planarians. However, ophis is not essential for GSC specification or maintenance and, therefore, defines a secondary role for planarian gonadal niche cells in promoting GSC differentiation. Our studies uncover the complement of planarian GPCRs and reveal previously unappreciated roles for these receptors in systemic and local (i.e., niche) regulation of germ cell development. PMID:27163480

  5. Identification of side population cells in chicken embryonic gonads.

    PubMed

    Bachelard, Elodie; Raucci, Franca; Montillet, Guillaume; Pain, Bertrand

    2015-02-01

    The side population (SP) phenotype, defined by the ability of a cell to efflux fluorescent dyes such as Hoechst, is common to several stem/progenitor cell types. In avian species, SP phenotype has been identified in pubertal and adult testes, but nothing is known about its expression during prenatal development of a male gonad. In this study, we characterized the Hoechst SP phenotype via the cytofluorimetric analysis of disaggregated testes on different days of chicken embryonic development. Male prenatal gonads contained a fraction of SP cells at each stage analyzed. At least two main SP fractions, named P3 and P4, were identified. The percentage of P3 fraction decreased as development proceeds, whereas P4 cell number was not affected by gonad growth. Functional inhibition of BCRP1 channel membrane using Verapamil and/or Ko143 showed that P3, but not P4 phenotype, was dependent on BCRP1 activity. Molecular analysis of both P3- and P4-sorted fractions revealed a differential RNA expression pattern, indicating that P3 cells mainly contained germinal stem cell markers, whereas P4 was preferentially composed of both Sertoli and Leydig cell progenitor markers. Finally, these findings provided evidence that the SP phenotype is a common feature of both germ and somatic cells detected in chicken developing testis.

  6. Primary gonadal damage following treatment of brain tumors in childhood

    SciTech Connect

    Ahmed, S.R.; Shalet, S.M.; Campbell, R.H.; Deakin, D.P.

    1983-10-01

    Gonadal function was studied in two groups of children previously treated for medulloblastoma with surgery followed by postoperative craniospinal irradiation. In group 1 but not in group 2, the children also received adjuvant chemotherapy for one to two years. All children in group 1 received a nitrosourea (BCNU or CCNU), plus vincristine in four and procarbazine in three patients. The nine children in group 1 showed clinical and biochemical evidence of gonadal damage with elevated serum FSH concentrations and, in the boys, small testes for their stage of pubertal development. In group 2 (n . 8), each child had completed pubertal development normally, the boys had adult sized testes and the girls regular menses. Gonadotropin values were normal in all eight children. We conclude that nitrosoureas were responsible for the gonadal damage in the children in group 1, with procarbazine also contributing to the damage in the three children who received this drug. In view of the limited proved value of adjuvant chemotherapy with nitrosoureas in the treatment of medulloblastoma, recognition of this serious complication of cytotoxic drug therapy may necessitate reassessing in which subgroups of children with medulloblastoma the benefits of adjuvant chemotherapy outweigh the complications.

  7. SHOX haploinsufficiency and overdosage: impact of gonadal function status

    PubMed Central

    Ogata, T.; Matsuo, N.; Nishimura, G.

    2001-01-01

    Since its discovery in 1997, knowledge about the SHOX gene has rapidly increased. In this review, we summarise clinical features and diagnostic and therapeutic implications in SHOX haploinsufficiency and overdosage. SHOX haploinsufficiency usually results in mesomelic short stature and Turner skeletal features, including Madelung deformity with puberty, in subjects with normal gonadal function. Thus, identification of early or mild signs of Madelung deformity is pivotal for the diagnosis, and gonadal suppression therapy may serve to mitigate the clinical features. By contrast, SHOX overdosage usually leads to long limbs and tall stature resulting from continued growth into the late teens in subjects with gonadal dysgenesis. Thus, the combination of tall stature and poor pubertal development is the key to diagnosis, and oestrogen therapy can help the prevention of unfavourably tall stature as well as the induction of sexual development. These findings, in conjunction with skeletal assessment in Turner syndrome and expression analysis during human embryogenesis, imply that SHOX functions as a repressor for growth plate fusion and skeletal maturation in the distal limbs and, thus, counteracts the skeletal maturing effects of oestrogens.


Keywords: SHOX; oestrogens; clinical features; practical implications PMID:11134233

  8. Adrenal-kidney-gonad complex measurements may not predict gonad-specific changes in gene expression patterns during temperature-dependent sex determination in the red-eared slider turtle (Trachemys scripta elegans).

    PubMed

    Ramsey, Mary; Crews, David

    2007-08-01

    Many turtles, including the red-eared slider turtle (Trachemys scripta elegans) have temperature-dependent sex determination in which gonadal sex is determined by temperature during the middle third of incubation. The gonad develops as part of a heterogenous tissue complex that comprises the developing adrenal, kidney, and gonad (AKG complex). Owing to the difficulty in excising the gonad from the adjacent tissues, the AKG complex is often used as tissue source in assays examining gene expression in the developing gonad. However, the gonad is a relatively small component of the AKG, and gene expression in the adrenal-kidney (AK) compartment may interfere with the detection of gonad-specific changes in gene expression, particularly during early key phases of gonadal development and sex determination. In this study, we examine transcript levels as measured by quantitative real-time polymerase chain reaction for five genes important in slider turtle sex determination and differentiation (AR, ERalpha, ERbeta, aromatase, and Sf1) in AKG, AK, and isolated gonad tissues. In all cases, gonad-specific gene expression patterns were attenuated in AKG versus gonad tissue. All five genes were expressed in the AK in addition to the gonad at all stages/temperatures. Inclusion of the AK compartment masked important changes in gonadal gene expression. In addition, AK and gonad expression patterns are not additive, and gonadal gene expression cannot be predicted from intact AKG measurements.

  9. Extraction and analysis of carotenoids from the New Zealand sea urchin Evechinus chloroticus gonads.

    PubMed

    Garama, Daniel; Bremer, Phil; Carne, Alan

    2012-01-01

    Sea urchin gonad (roe) is a highly valued food in Japan and North America. Gonad price is strongly influenced by quality, with appearance, especially colour being a major determinant. Previous attempts to extract a carotenoid profile from the New Zealand sea urchin species Evechinus chloroticus have been challenging due to the large amount of lipid present in the gonad. A carotenoid extraction and high performance liquid chromatography (HPLC) analysis method was developed to reduce lipid contamination by incorporating a saponification and lipid cold precipitation in the extraction procedure. This method enabled greater carotenoid purity and enhanced analysis by HPLC. Echinenone was found to be the main carotenoid present in all E. chloroticus gonads. Dark coloured gonads contained higher levels of fucoxanthin/fucoxanthinol, β-carotene and xanthophylls such as astaxanthin and canthaxanthin. This information on the modification and deposition of carotenoids will help in the development of diets to enhance gonad colour.

  10. An XX female with sexual infantilism, absent gonads, and lack of Müllerian ducts.

    PubMed Central

    Levinson, G; Zárate, A; Guzmán-Toledano, R; Canales, E S; Jiménez, M

    1976-01-01

    A patient with a 46,XX chromosome constitution showed the following main characteristics: lack of secondary sexual development, female external genitalia with absence of vagina, no gonadal structures, and complete lack of internal genitalia. This is a variant of the gonadal agenesis syndrome so far only described in association with and XY chromosome component. Endrocinology demonstrated that in the absence of gonadal feedback the pituitary responsiveness to synthetic luteinizing hormone-releasing hormone was increased. Images PMID:1271429

  11. Gonadal Transcriptome Analysis in Sterile Double Haploid Japanese Flounder

    PubMed Central

    Wang, Guixing; Jiang, Hongbo; Wang, Yufen; Sun, Zhaohui; Jiang, Xiufeng; Yu, Qinghai; Liu, Haijin

    2015-01-01

    Sterility is a serious problem that can affect all bionts. In teleosts, double haploids (DHs) induced by mitogynogenesis are often sterile. This sterility severely restricts the further application of DHs for production of clones, genetic analysis, and breeding. However, sterile DH individuals are good source materials for investigation of the molecular mechanisms of gonad development, especially for studies into the role of genes that are indispensable for fish reproduction. Here, we used the Illumina sequencing platform to analyze the transcriptome of sterile female DH Japanese flounder in order to identify major genes that cause sterility and to provide a molecular basis for an intensive study of gonadal development in teleosts. Through sequencing, assembly, and annotation, we obtained 52,474 contigs and found that 60.7% of these shared homologies with existing sequences. A total of 1225 differentially expressed unigenes were found, including 492 upregulated and 733 downregulated genes. Gene Ontology and KEGG analyses showed that genes showing significant upregulation, such as CYP11A1, CYP11B2, CYP17, CYP21, HSD3β, bcl2l1, and PRLR, principally correlated with sterol metabolic process, steroid biosynthetic process, and the Jak-stat signaling pathway. The significantly downregulated genes were primarily associated with immune response, antigen processing and presentation, cytokine–cytokine receptor interaction, and protein digestion and absorption. Using a co-expression network analysis, we conducted a comprehensive comparison of gene expression in the gonads of fertile and sterile female DH Japanese flounder. Identification of genes showing significantly different expression will provide further insights into DH reproductive dysfunction and oocyte maturation processes in teleosts. PMID:26580217

  12. Hypothalamic-pituitary-gonadal endocrine system in the hagfish.

    PubMed

    Nozaki, Masumi

    2013-12-30

    The hypothalamic-pituitary system is considered to be a seminal event that emerged prior to or during the differentiation of the ancestral agnathans (jawless vertebrates). Hagfishes as one of the only two extant members of the class of agnathans are considered the most primitive vertebrates known, living or extinct. Accordingly, studies on their reproduction are important for understanding the evolution and phylogenetic aspects of the vertebrate reproductive endocrine system. In gnathostomes (jawed vertebrates), the hormones of the hypothalamus and pituitary have been extensively studied and shown to have well-defined roles in the control of reproduction. In hagfish, it was thought that they did not have the same neuroendocrine control of reproduction as gnathostomes, since it was not clear whether the hagfish pituitary gland contained tropic hormones of any kind. This review highlights the recent findings of the hypothalamic-pituitary-gonadal endocrine system in the hagfish. In contrast to gnathostomes that have two gonadotropins (GTH: luteinizing hormone and follicle-stimulating hormone), only one pituitary GTH has been identified in the hagfish. Immunohistochemical and functional studies confirmed that this hagfish GTH was significantly correlated with the developmental stages of the gonads and showed the presence of a steroid (estradiol) feedback system at the hypothalamic-pituitary levels. Moreover, while the identity of hypothalamic gonadotropin-releasing hormone (GnRH) has not been determined, immunoreactive (ir) GnRH has been shown in the hagfish brain including seasonal changes of ir-GnRH corresponding to gonadal reproductive stages. In addition, a hagfish PQRFamide peptide was identified and shown to stimulate the expression of hagfish GTHβ mRNA in the hagfish pituitary. These findings provide evidence that there are neuroendocrine-pituitary hormones that share common structure and functional features compared to later evolved vertebrates.

  13. Gonadal Transcriptome Analysis in Sterile Double Haploid Japanese Flounder.

    PubMed

    Zhang, Xiaoyan; Hou, Jilun; Wang, Guixing; Jiang, Hongbo; Wang, Yufen; Sun, Zhaohui; Jiang, Xiufeng; Yu, Qinghai; Liu, Haijin

    2015-01-01

    Sterility is a serious problem that can affect all bionts. In teleosts, double haploids (DHs) induced by mitogynogenesis are often sterile. This sterility severely restricts the further application of DHs for production of clones, genetic analysis, and breeding. However, sterile DH individuals are good source materials for investigation of the molecular mechanisms of gonad development, especially for studies into the role of genes that are indispensable for fish reproduction. Here, we used the Illumina sequencing platform to analyze the transcriptome of sterile female DH Japanese flounder in order to identify major genes that cause sterility and to provide a molecular basis for an intensive study of gonadal development in teleosts. Through sequencing, assembly, and annotation, we obtained 52,474 contigs and found that 60.7% of these shared homologies with existing sequences. A total of 1225 differentially expressed unigenes were found, including 492 upregulated and 733 downregulated genes. Gene Ontology and KEGG analyses showed that genes showing significant upregulation, such as CYP11A1, CYP11B2, CYP17, CYP21, HSD3β, bcl2l1, and PRLR, principally correlated with sterol metabolic process, steroid biosynthetic process, and the Jak-stat signaling pathway. The significantly downregulated genes were primarily associated with immune response, antigen processing and presentation, cytokine-cytokine receptor interaction, and protein digestion and absorption. Using a co-expression network analysis, we conducted a comprehensive comparison of gene expression in the gonads of fertile and sterile female DH Japanese flounder. Identification of genes showing significantly different expression will provide further insights into DH reproductive dysfunction and oocyte maturation processes in teleosts. PMID:26580217

  14. Assessment of thyroid and gonadal function in liver diseases

    PubMed Central

    Kharb, Sandeep; Garg, M. K.; Puri, Pankaj; Brar, Karninder S.; Pandit, Aditi; Srivastava, Sharad

    2015-01-01

    Introduction: Liver is involved with the synthesis of carrier proteins and metabolism of various hormones and liver diseases may, therefore, be associated with various endocrine disturbances. This study was conducted to assess thyroid and gonadal function in subjects with acute hepatitis (AH), chronic liver disease (CLD), and those who had undergone liver transplantation (LT). Materials and Methods: Patients with AH, CLD with Child-Pugh stage A (CLD-1) and Child-Pugh stage B or C (CLD-2), and LT seen at our tertiary level hospital were assessed clinically, biochemically, and for thyroid and gonadal functions besides 25 healthy controls. Results: Thyroid dysfunction and hypogonadism were present in 14 (16%) and 24 (28%) patients with liver diseases respectively. Among thyroid dysfunction, the commonest was sick euthyroid syndrome six (7%), followed by subclinical hypothyroidism in three patients (3.5%), subclinical hyperthyroidism and thyrotoxicosis in two patients each (2.3%) and overt hypothyroidism in one patient. Among patients with LT and AH groups, the only abnormality was significantly lower total T3 compared with healthy controls. The CLD2 group had significantly lower levels of all thyroid hormones compared with controls and CLD1 group. Hypogonadism was commonest in patients with CLD-2 (14; 50%) followed by LT (3; 33%), CLD-1 (4; 20%), and AH (3; 14%). Hypogonadism was predicted by older age, lower levels of serum albumin, total cholesterol, and triglycerides and higher levels of plasma glucose, serum bilirubin, aspartate transaminases, and international normalized ratio. Gonadal functions showed recovery following LT. Conclusions: Thyroid dysfunction and hypogonadism form an important part of the spectrum of acute and CLD, and patients with LT. Deterioration of synthetic functions of liver disease predicts presence of hypogonadism. PMID:25593833

  15. Meiotic wave adds extra asymmetry to the development of female chicken gonads.

    PubMed

    de Melo Bernardo, Ana; Heeren, A Marijne; van Iperen, Liesbeth; Fernandes, Maria Gomes; He, Nannan; Anjie, Stafford; Noce, Toshiaki; Ramos, Ester Silveira; de Sousa Lopes, Susana M Chuva

    2015-10-01

    Development of female gonads in the chicken is asymmetric. This asymmetry affects gene expression, morphology, and germ cell development; consequently only the left ovary develops into a functional organ, whereas the right ovary remains vestigial. In males, on the other hand, both gonads develop into functional testes. Here, we revisited the development of asymmetric traits in female (and male) chicken gonads between Hamburger Hamilton stage 16 (HH16) and hatching. At HH16, primordial germ cells migrated preferentially to the left gonad, accumulating in the left coelomic hinge between the gut mesentery and developing gonad in both males and females. Using the meiotic markers SYCP3 and phosphorylated H2AFX, we identified a previously undescribed, pronounced asymmetryc meiotic progression in the germ cells located in the central, lateral, and extreme cortical regions of the left female gonad from HH38 until hatching. Moreover, we observed that--in contrast to the current view--medullary germ cells are not apoptotic, but remain arrested in pre-leptotene until hatching. In addition to the systematic analysis of the asymmetric distribution of germ cells in female chicken gonads, we propose an updated model suggesting that the localization of germ cells--in the left or right gonad; in the cortex or medulla of the left gonad; and in the central part or the extremities of the left cortex--has direct consequences for their development and participation in adult reproduction. PMID:26096940

  16. State of the art review in gonadal dysgenesis: challenges in diagnosis and management.

    PubMed

    McCann-Crosby, Bonnie; Mansouri, Roshanak; Dietrich, Jennifer E; McCullough, Laurence B; Sutton, V Reid; Austin, Elise G; Schlomer, Bruce; Roth, David R; Karaviti, Lefkothea; Gunn, Sheila; Hicks, M John; Macias, Charles G

    2014-01-01

    Gonadal dysgenesis, a condition in which gonadal development is interrupted leading to gonadal dysfunction, is a unique subset of disorders of sexual development (DSD) that encompasses a wide spectrum of phenotypes ranging from normally virilized males to slightly undervirilized males, ambiguous phenotype, and normal phenotypic females. It presents specific challenges in diagnostic work-up and management. In XY gonadal dysgenesis, the presence of a Y chromosome or Y-chromosome material renders the patient at increased risk for developing gonadal malignancy. No universally accepted guidelines exist for identifying the risk of developing a malignancy or for determining either the timing or necessity of performing a gonadectomy in patients with XY gonadal dysgenesis. Our goal was to evaluate the literature and develop evidence-based medicine guidelines with respect to the diagnostic work-up and management of patients with XY gonadal dysgenesis. We reviewed the published literature and used the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) system when appropriate to grade the evidence and to provide recommendations for the diagnostic work-up, malignancy risk stratification, timing or necessity of gonadectomy, role of gonadal biopsy, and ethical considerations for performing a gonadectomy. Individualized health care is needed for patients with XY gonadal dysgenesis, and the decisions regarding gonadectomy should be tailored to each patient based on the underlying diagnosis and risk of malignancy. Our recommendations, based on the evidence available, add an important component to the diagnostic and management armament of physicians who treat patients with these conditions.

  17. Relationships between glucocorticoids and gonadal steroids in rheumatoid arthritis.

    PubMed

    da Silva, José António P

    2002-06-01

    Gender and sex hormones are strongly related to the incidence and progression of autoimmune rheumatic diseases. Although sex steroids have been shown to have direct effects on the immune system, their influence in vivo may be mediated via interactions with third party systems including the hypothalamic-pituitary-adrenal axis. Such interactions are well demonstrated in experimental animals. In humans, there is increasing, although indirect, evidence that these interactions also occur. Possible interactions at the cell and gene level, with mutual antagonism or synergy between cortico- and gonadal steroids, open new exciting hypotheses that await clarification.

  18. Characterization of gonadal transcriptomes from Nile tilapia (Oreochromis niloticus) reveals differentially expressed genes.

    PubMed

    Tao, Wenjing; Yuan, Jing; Zhou, Linyan; Sun, Lina; Sun, Yunlv; Yang, Shijie; Li, Minghui; Zeng, Sheng; Huang, Baofeng; Wang, Deshou

    2013-01-01

    Four pairs of XX and XY gonads from Nile tilapia were sequenced at four developmental stages, 5, 30, 90, and 180 days after hatching (dah) using Illumina Hiseq(TM) technology. This produced 28 Gb sequences, which were mapped to 21,334 genes. Of these, 259 genes were found to be specifically expressed in XY gonads, and 69 were found to be specific to XX gonads. Totally, 187 XX- and 1,358 XY-enhanced genes were identified, and 2,978 genes were found to be co-expressed in XX and XY gonads. Almost all steroidogenic enzymes, including cyp19a1a, were up-regulated in XX gonads at 5 dah; but in XY gonads these enzymes, including cyp11b2, were significantly up-regulated at 90 dah, indicating that, at a time critical to sex determination, the XX fish produced estrogen and the XY fish did not produce androgens. The most pronounced expression of steroidogenic enzyme genes was observed at 30 and 90 dah for XX and XY gonads, corresponding to the initiation of germ cell meiosis in the female and male gonads, respectively. Both estrogen and androgen receptors were found to be expressed in XX gonads, but only estrogen receptors were expressed in XY gonads at 5 dah. This could explain why exogenous steroid treatment induced XX and XY sex reversal. The XX-enhanced expression of cyp19a1a and cyp19a1b at all stages suggests an important role for estrogen in female sex determination and maintenance of phenotypic sex. This work is the largest collection of gonadal transcriptome data in tilapia and lays the foundation for future studies into the molecular mechanisms of sex determination and maintenance of phenotypic sex in non-model teleosts.

  19. [XY gonadal dysgenesis with female phenotype (author's transpl)].

    PubMed

    Trias, J V; Martínez, F B

    1975-01-01

    In this paper, we are dealing with the study of a case of multiple somatic malformations, with external female genitals and 46 XY caryotype. The anatomical and histological study of the genital organs, allows us to verify the existence of internal genital organs; consisting essentially in tubes, bicornous uterus, a gonadal ligament in a normotopical position, Wolffian remains and the absence of a vagina. The external female genitals are completely normal. When we interpreted these findings, we paid special attention to the relation existing between the abnormal presence of the Wolffian remains, male genotype, and typical female genital structures. Taking account of the latest scientific advances concerning genital development, we considered the possibility of the existence of secretions of a "masculinizing" substance from the gonad, before its morphological differentiation, which was interrupted by an etiological undetermined noxa. When this evolution was arrested, together with the secretions of the masculinizing substance, the genital development continued normally for a female. The terminal teratogenic period for this malformation is situated from the 5th to the 6th week of gestation (human embryos from 11 to 14 mm., Streeter Horizon XVII).

  20. Role of the prion protein family in the gonads

    PubMed Central

    Allais-Bonnet, Aurélie; Pailhoux, Eric

    2014-01-01

    The prion-gene family comprises four members named PRNP (PRPc), PRND (Doppel), PRNT (PRT), and SPRN (Shadoo). According to species, PRND is located 16–52 kb downstream from the PRNP locus, whereas SPRN is located on another chromosome. The fourth prion-family gene, PRNT, belongs to the same genomic cluster as PRNP and PRND in humans and bovidae. PRNT and PRND possibly resulted from a duplication event of PRND and PRNP, respectively, that occurred early during eutherian species divergence. Although most of the studies concerning the prion-family has been done on PRPc and its involvement in transmissible neurodegenerative disorders, different works report some potential roles of these proteins in the reproductive function of both sexes. Among them, a clear role of PRND, that encodes for the Doppel protein, in male fertility has been demonstrated through gene targeting studies in mice. In other species, Doppel seems to play a role in testis and ovary development but its cellular localization is variable according to the gonadal developmental stage and to the mammalian species considered. For the other three genes, their roles in reproductive function appear ill-defined and/or controversial. The present review aimed to synthesize all the available data on these prion-family members and their relations with reproductive processes, mainly in the gonad of both sexes. PMID:25364761

  1. Male pituitary-gonadal dysfunction following severe traumatic brain injury.

    PubMed

    Lee, S C; Zasler, N D; Kreutzer, J S

    1994-01-01

    A prospective study was conducted to evaluate pituitary-gonadal function and correlated parameters in 21 adult males with severe traumatic brain injury during acute inpatient rehabilitation. Serum concentrations of testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were measured within 1 week after the patient was transferred to the rehabilitation unit. Fourteen of 21 patients (67%) had abnormally low testosterone levels. One of 21 patients had a subnormal FSH level and one had a supranormal level. Three of 21 patients had subnormal LH levels and two had supranormal levels. There was no correlation between the severity of brain injury and the levels of testosterone, FSH or LH. The presence of increased intracranial pressure, hypoxia, skull fracture or abnormal CT findings had no significant influence on the levels of testosterone, FSH or LH. The high incidence of hypotestosteronaemia in survivors of severe traumatic brain injury is seemingly more related to accompanying physiological stressors rather than structural or neurochemical disruption of the hypothalamic-pituitary-gonadal axis. Early identification is important relative to the potential neuromedical and rehabilitative consequences of prolonged hypotestosteronaemia in this patient population.

  2. Hypothalamic-pituitary-adrenocortical and gonadal functions in rheumatoid arthritis.

    PubMed

    Cutolo, M; Sulli, A; Pizzorni, C; Craviotto, C; Straub, R H

    2003-05-01

    Rheumatoid arthritis (RA) as well as most autoimmune disorders results from a combination of several predisposing factors including the relations between epitopes of the trigger agent (i.e., virus, self-antigens) and histocompatibility epitopes (i.e., HLA), the status of the stress response system including the hypothalamic-pituitary-adrenocortical axis (HPA) and the sympathetic nervous system (SNS), as well as the gonadal hormones (hypothalamic-pituitary-gonadal axis, HPG), with estrogens implicated as enhancers of the immune response and androgens and progesterone as natural suppressors. The regular observation of reduced cortisol and adrenal androgen secretion during testing in RA patients not treated with glucocorticoids should clearly be regarded as "relative adrenal insufficiency" in the setting of a sustained inflammatory process, as shown by high interleukin (IL)-6 levels. In polymyalgia rheumatica, several pathogenetic and clinical aspects of the disease might well overlap RA, at least with elderly onset RA (EORA). Therefore, reduced production of adrenal hormones (i.e., cortisol, DHEAS) at baseline in active and untreated patients with polymyalgia rheumatica was detected. The defect was mainly related to altered adrenal responsiveness to ACTH stimulation (i.e., increased 17-OHP), at least in untreated patients with polymyalgia rheumatica. Finally, normal serum estrogen and low androgen levels, but high synovial fluid estrogen and much lower androgen levels, have been found in RA patients, supporting the fundamental role of the peripheral sex hormone metabolism in the manifestations of the disease.

  3. Gonadal differentiation in reptiles exhibiting environmental sex determination.

    PubMed

    Kohno, Satomi; Parrott, Benjamin B; Yatsu, Ryohei; Miyagawa, Shinichi; Moore, Brandon C; Iguchi, Taisen; Guillette, Louis

    2014-01-01

    As temperature-dependent sex determination (TSD) and homozygote or heterozygote genetic sex determination (GSD) exist in multiple reptilian taxa, they represent sex determination systems that have emerged de novo. Current investigations have revealed that the genetic mechanisms used by various reptilian species are similar to those used by other vertebrates. However, the recent completion or near completion of various reptilian genome projects suggests that new studies examining related species with and without TSD could begin to provide additional insight into the evolution of TSD and GSD in vertebrate ancestors. Major questions still remain concerning germ cell migration and specification, the differentiation of gonadal accessory cells, such as the Sertoli cells and granulosa cells of the developing testis and ovary, respectively, and the mechanisms by which gene expression is regulated during TSD events. Further, reptilian sentinels and their mechanisms of gonadogenesis will likely remain important indicator species for environmental health. Thus, ongoing and new investigations need to tie molecular information to gonadal morphogenesis and function in reptiles. Such data will not only provide important information for an understanding of the evolution of these phenomena in vertebrates, but could also provide an important understanding of the health of the environment around us.

  4. Characterization of gonadal transcriptomes from the turbot (Scophthalmus maximus).

    PubMed

    Hu, Yulong; Huang, Meng; Wang, Weiji; Guan, Jiantao; Kong, Jie

    2016-01-01

    The mechanisms underlying sexual reproduction and sex ratio determination remains unclear in turbot, a flatfish of great commercial value. And there is limited information in the turbot database regarding genes related to the reproductive system. Here, we conducted high-throughput transcriptome profiling of turbot gonad tissues to better understand their reproductive functions and to supply essential gene sequence information for marker-assisted selection programs in the turbot industry. In this study, two gonad libraries representing sex differences in Scophthalmus maximus yielded 453 818 high-quality reads that were assembled into 24 611 contigs and 33 713 singletons by using 454 pyrosequencing, 13 936 contigs and singletons (CS) of which were annotated using BLASTx. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analyses revealed that various biological functions and processes were associated with many of the annotated CS. Expression analyses showed that 510 genes were differentially expressed in males versus females; 80% of these genes were annotated. In addition, 6484 and 6036 single nucleotide polymorphisms (SNPs) were identified in male and female libraries, respectively. This transcriptome resource will serve as the foundation for cDNA or SNP microarray construction, gene expression characterization, and sex-specific linkage mapping in turbot. PMID:26745327

  5. Gonadal differentiation in reptiles exhibiting environmental sex determination.

    PubMed

    Kohno, Satomi; Parrott, Benjamin B; Yatsu, Ryohei; Miyagawa, Shinichi; Moore, Brandon C; Iguchi, Taisen; Guillette, Louis

    2014-01-01

    As temperature-dependent sex determination (TSD) and homozygote or heterozygote genetic sex determination (GSD) exist in multiple reptilian taxa, they represent sex determination systems that have emerged de novo. Current investigations have revealed that the genetic mechanisms used by various reptilian species are similar to those used by other vertebrates. However, the recent completion or near completion of various reptilian genome projects suggests that new studies examining related species with and without TSD could begin to provide additional insight into the evolution of TSD and GSD in vertebrate ancestors. Major questions still remain concerning germ cell migration and specification, the differentiation of gonadal accessory cells, such as the Sertoli cells and granulosa cells of the developing testis and ovary, respectively, and the mechanisms by which gene expression is regulated during TSD events. Further, reptilian sentinels and their mechanisms of gonadogenesis will likely remain important indicator species for environmental health. Thus, ongoing and new investigations need to tie molecular information to gonadal morphogenesis and function in reptiles. Such data will not only provide important information for an understanding of the evolution of these phenomena in vertebrates, but could also provide an important understanding of the health of the environment around us. PMID:24642710

  6. Oncofertility in Canada: gonadal protection and fertility-sparing strategies

    PubMed Central

    Ronn, R.; Holzer, H.E.G.

    2013-01-01

    Background Cancer can be a devastating diagnosis. In particular, malignancy and its indicated treatments have profoundly negative effects on the fertility of young cancer patients. Oncofertility has emerged as a new interdisciplinary field to address the issue of gonadotoxicity associated with cancer therapies and to facilitate fertility preservation. In Canada, fertility issues are often inadequately addressed despite the availability of resources. The goal of this four-part series is to facilitate systemic improvements in fertility preservation for adolescent and young adult Canadians with a new diagnosis of cancer. Methods Here, we review the fertility preservation measures currently available. Medical and surgical strategies are both outlined. Results Fertility-preserving strategies and gonadal protection have demonstrated variable success in a number of approaches. The value of hormone suppression is still in question for women. Progestins for endometrial cancer and alternative chemotherapies are other medical approaches. Gonadal shielding and protective surgical approaches have also been attempted. Conclusions The techniques discussed here may be selectively considered and integrated into patient care in an attempt to preserve future fertility before initiating cancer treatment. PMID:24311962

  7. Gonadal development and germ cell tumors in mouse and humans.

    PubMed

    Dolci, Susanna; Campolo, Federica; De Felici, Massimo

    2015-09-01

    In multicellular organisms, proper development of gonads and germ cells is essential for the transmission of genetic information to the next generations and eventually for the survival of the species. For this reason, germline development is finely regulated to control germ cell proliferation, survival and differentiation. Disruption of such controls can lead to infertility or germ cell tumors (GCTs). GCTs are particularly hideous pathologies since they occur mainly in neonates, infants, and children, rarely in the adults. They arise primarily in the testes and ovaries, though they can also develop in extragonadal sites along the midline of the body and the brain. Many similarities exist between most types of GCTs of the ovary and testis, including a morphological resemblance (often constituting a caricature of normal embryogenesis) and a similar pattern of chromosomal alterations. Furthermore, families with both ovarian and testicular GCTs have been reported, suggesting a possible common genetic etiology. This review focuses on the cellular processes, differentiation events and molecular mechanisms occurring during gonad development in mice and humans whose disturbance can be implicated in GCT formation.

  8. Thermal and endocrine regulation of gonadal apoptosis during sex differentiation in pejerrey Odontesthes bonariensis.

    PubMed

    Yamamoto, Y; Hattori, R S; Kitahara, A; Kimura, H; Yamashita, M; Strüssmann, C A

    2013-01-01

    The fate of the differentiating gonads in pejerrey Odontesthes bonariensis is determined by the environmental water temperature experienced by the larvae during the critical period of sex determination. We previously reported a link between apoptosis, temperature and sex differentiation in this species. To clarify this link, we subjected larvae to thermal and endocrine treatments between hatching and the onset of histological sex differentiation of the gonads and assessed the patterns of gonadal development and apoptosis by light microscopic histology and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) analysis, respectively. Apoptotic labeling was widespread among somatic cells of the anterior region of the right gonads of fish reared at the male-producing temperature (MPT) and part of the fish at the mixed sex-producing temperature prior to sex differentiation. In contrast, TUNEL-positive cells were rarely observed in gonads at the female-producing temperature (FPT). Administration of exogenous estrogen completely prevented MPT-induced masculinization, induced feminization and reduced gonadal apoptosis, whereas an aromatase inhibitor (fadrozole) induced TUNEL signals in the gonads of FPT-reared larvae. These results provide strong evidence that apoptosis in somatic cells in the right lobe of the gonads might play a key role in testicular differentiation in pejerrey and that estrogens are involved in the regulation of this process.

  9. Common features and differences of the hypothalamic-pituitary-gonadal axis in male and female.

    PubMed

    Dagklis, Themistoklis; Ravanos, Kostas; Makedou, Kali; Kourtis, Anargyros; Rousso, David

    2015-01-01

    Male and female reproductive axis, comprised of hypothalamus, pituitary and gonads, present common features and differences, discussed in this review. These include the way hypothalamus regulates pituitary function, and the way pituitary, in turn, affects gonadal function. Finally, age plays an important role in axis regulation, in both genders.

  10. Terminology of Gonadal Anomalies in Fish and Amphibians Resulting from Chemical Exposures

    EPA Science Inventory

    This paper reviews the terms that have been used to describe various types of gonadal deformities and lesions in amphibians and fish, identifies the body of literature that has reported effects on gonad morphology/histology, and suggests a standardized set of terms and definition...

  11. Correspondence between Gonadal Steroid Hormone Concentrations and Secondary Sexual Characteristics Assessed by Clinicians, Adolescents, and Parents

    ERIC Educational Resources Information Center

    Huang, Bin; Hillman, Jennifer; Biro, Frank M.; Ding, Lili; Dorn, Lorah D.; Susman, Elizabeth J.

    2012-01-01

    Adolescent sexual maturation is staged using Tanner criteria assessed by clinicians, parents, or adolescents. The physiology of sexual maturation is driven by gonadal hormones. We investigate Tanner stage progression as a function of increasing gonadal hormone concentration and compare performances of different raters. Fifty-six boys (mean age,…

  12. Decision Processes During Development of Molecular Biomarkers for Gonadal Phenotypic Sex

    EPA Science Inventory

    Molecular biomarkers for determination of gonadal phenotypic sex in the Japanese medaka (Oryzias latipes), will serve as a case study. The medaka has unique features that aid in the development of appropriate molecular biomarkers of gonad phenotype, a) genetic sex can be determin...

  13. Proteomic analysis of three gonad types of swamp eel reveals genes differentially expressed during sex reversal

    PubMed Central

    Sheng, Yue; Zhao, Wei; Song, Ying; Li, Zhigang; Luo, Majing; Lei, Quan; Cheng, Hanhua; Zhou, Rongjia

    2015-01-01

    A variety of mechanisms are engaged in sex determination in vertebrates. The teleost fish swamp eel undergoes sex reversal naturally and is an ideal model for vertebrate sexual development. However, the importance of proteome-wide scanning for gonad reversal was not previously determined. We report a 2-D electrophoresis analysis of three gonad types of proteomes during sex reversal. MS/MS analysis revealed a group of differentially expressed proteins during ovary to ovotestis to testis transformation. Cbx3 is up-regulated during gonad reversal and is likely to have a role in spermatogenesis. Rab37 is down-regulated during the reversal and is mainly associated with oogenesis. Both Cbx3 and Rab37 are linked up in a protein network. These datasets in gonadal proteomes provide a new resource for further studies in gonadal development. PMID:25985063

  14. Psychoneuroendocrinology of depression. Hypothalamic-pituitary-gonadal axis.

    PubMed

    Young, E; Korszun, A

    1998-06-01

    Women are more susceptible than men to depression, particularly during periods of rapid fluctuation of gonadal hormones, such as premenstrually, postpartum, and during the climacteric. This review summarizes the evidence for the association of depression with abnormalities in reproductive hormones. Although there are similarities in stress hormones changes between depressed women and women with stress-related amenorrhea, no abnormalities in LH activity have been documented in depression. Similarly no abnormalities in LH, estradiol, or progesterone have been documented in premenstrual syndrome (PMS), although complete elimination of monthly cycling with leuprolide improves mood. Some studies have suggested beneficial effects of estrogen on mood in postmenopausal women but as yet there have been no adequately controlled studies of estrogen treatment of either premenopausal or postmenopausal women.

  15. Hypothalamic-pituitary-gonadal dysfunction in men using cimetidine.

    PubMed

    Van Thiel, D H; Gavaler, J S; Smith, W I; Paul, G

    1979-05-01

    We studied the effect of cimetidine therapy (1200 mg per day by mouth for nine weeks) on the hypothalamic-pituitary-gonadal axis of seven men. There was a 43 per cent mean reduction in sperm count after therapy. The luteinizing hormone response to luteinizing hormone releasing factor was also reduced, and a statistically significnat rise in plasma testosterone occurred, although it was less than that before therapy. Gonadotropin responses to provocative clomiphene stimulation were inadequate when compared with those of controls. Cimetidine did not affect the responses of thyroid-stimulating hormone, prolactin, growth hormone and thyroxine to thyrotropin releasing factor. Caution is advisable in administration of cimetidine for prolonged periods to young men.

  16. Psychoneuroendocrinology of depression. Hypothalamic-pituitary-gonadal axis.

    PubMed

    Young, E; Korszun, A

    1998-06-01

    Women are more susceptible than men to depression, particularly during periods of rapid fluctuation of gonadal hormones, such as premenstrually, postpartum, and during the climacteric. This review summarizes the evidence for the association of depression with abnormalities in reproductive hormones. Although there are similarities in stress hormones changes between depressed women and women with stress-related amenorrhea, no abnormalities in LH activity have been documented in depression. Similarly no abnormalities in LH, estradiol, or progesterone have been documented in premenstrual syndrome (PMS), although complete elimination of monthly cycling with leuprolide improves mood. Some studies have suggested beneficial effects of estrogen on mood in postmenopausal women but as yet there have been no adequately controlled studies of estrogen treatment of either premenopausal or postmenopausal women. PMID:9670228

  17. Sex Chromosome Mosaicism in the Gonads of DSD Patients: A Karyotype/Phenotype Correlation.

    PubMed

    Kamel, Alaa K; Abd El-Ghany, Hoda M; Mekkawy, Mona K; Makhlouf, Manal M; Mazen, Inas M; El Dessouky, Nabil; Mahmoud, Wael; Abd El Kader, Shereen A

    2015-01-01

    Sex chromosome mosaicism results in a large clinical spectrum of disorders of sexual development (DSD). The percentage of 45,X cells in the developing gonad plays a major role in sex determination. However, few reports on the gonadal mosaic status have been published, and the phenotype is usually correlated with peripheral lymphocyte karyotypes, which makes the phenotype prediction imprecise. This study was conducted on 7 Egyptian DSD patients to demonstrate the effect of sex chromosome constitution of both blood lymphocytes and gonadal tissues on the phenotypic manifestations. Conventional cytogenetic and FISH analyses of blood lymphocytes were conducted, and laparoscopy with gonadal biopsy was performed for histopathologic examination and FISH analysis. Gonosomal mosaicism was detected in 3 patients who had a non-mosaic chromosome pattern in blood lymphocytes. Two patients showed the same type of sex chromosome mosaicism in both the blood and gonadal tissues but with different distributions. Two other patients revealed a non-mosaic pattern in both tissues. The present study elucidates the importance of examining sex chromosome mosaicism in gonadal tissues of DSD patients and highlights the critical role of 45,X mosaicism which can lead to serious effects during early gonadal organogenesis.

  18. Minireview: Endocannabinoids and gonadal hormones: bidirectional interactions in physiology and behavior.

    PubMed

    Gorzalka, Boris B; Dang, Silvain S

    2012-03-01

    Endocannabinoids act as a major neuromodulatory system in a variety of physiological and behavioral functions. Three major lines of evidence suggest that the endocannabinoid system interacts with gonadal hormones. First, the endocannabinoid system is implicated in behaviors and physiological functions that are known to be regulated in part by gonadal hormones. Second, receptors and metabolic enzymes of the endocannabinoid system are localized extensively on structures in the hypothalamic-pituitary-gonadal axis. Third, changes in levels of gonadal hormones alter endocannabinoid signaling. Here we reviewed and summarized the current evidence regarding the interaction between the endocannabinoid system and androgens, estrogens, and progesterone. Overall, it appears that bidirectional interactions characterize the relationship between endocannabinoids and gonadal hormones, with endocannabinoids down-regulating hypothalamic-pituitary-gonadal activity and gonadal hormones modulating protein expression in the endocannabinoid system. An understanding of these interactions will have implications for elucidating the neuroendocrine mechanisms underlying a number of behavioral and physiological functions as well as potential pharmaceutical treatments for disorders of these functions.

  19. Over-expression of DMRT1 induces the male pathway in embryonic chicken gonads

    PubMed Central

    Lambeth, Luke; Raymond, Christopher S.; Roeszler, Kelly N.; Kuroiwa, Asato; Nakata, Tomohiro; Zarkower, David; Smith, Craig A.

    2014-01-01

    DMRT1 encodes a conserved transcription factor with an essential role in gonadal function. In the chicken, DMRT1 is located on the Z sex chromosome and is currently the best candidate master regulator of avian gonadal sex differentiation. We previously showed that knockdown of DMRT1 expression during the period of sexual differentiation induces feminisation of male embryonic chicken gonads. This gene is therefore necessary for proper testis development in the chicken. However, whether it is sufficient to induce testicular differentiation has remained unresolved. We show here that over-expression of DMRT1 induces male pathway genes and antagonises the female pathway in embryonic chicken gonads. Ectopic DMRT1 expression in female gonads induces localised SOX9 and AMH expression. It also induces expression of the recently identified Z-linked male factor, Hemogen (HEMGN). Masculinised gonads show evidence of cord-like structures and retarded female-type cortical development. Furthermore, expression of the critical feminizing enzyme, aromatase, is reduced in the presence of over-expressed DMRT1. These data indicate that DMRT1 is an essential sex-linked regulator of gonadal differentiation in avians, and that it likely acts via a dosage mechanism established through the lack of global Z dosage compensation in birds. PMID:24576538

  20. Early Gonadal Differentiation of the Protogynous Red Spotted Grouper, Epinephelus akaara

    PubMed Central

    Kim, Hyun Kyu; Kim, Jung-Hyun; Kim, Woo Sik; Baek, Hea Ja; Kwon, Joon Yeong

    2015-01-01

    Red spotted grouper, Epinephelus akaara is a popular aquaculture species in many Asian countries. This species is a protogynous hermaphrodite that first differentiates into female and changes to male later. Due to this reproductive characteristic, stable supply of male and female gametes is a key to the success of seed production in this species. Thus, understanding early gonadal differentiation is required to develop effective sex control techniques. Red spotted grouper were reared in indoor tanks and sampled every 5 days from 40 days post-hatch (DPH) to 130 DPH. Changes of gonadal tissues were examined and analyzed by means of histology. A pair of gonadal primordium has already existed underneath the kidney in the posterior part of the body cavity at 38 DPH when this study began. Gonadal primordia of 38, 40 DPH consisted of germ cells surrounded by a few somatic cells. The blood vessel was observed in the gonadal primordium at 45 DPH. The number of somatic cells and size of gonadal primordium increased age-dependently up to 60 DPH. Formation of ovarian cavity was obvious by two protuberant aggregations of somatic cells at 65 DPH. Completed ovarian cavity and oogonia were first observed in the gonad of one fish sample at 105 DPH. Based on these histological observations, it can be suggested that induction of primary male differentiation could be more successfully applied at around 60 DPH in this species. PMID:26973972

  1. Meiotic wave adds extra asymmetry to the development of female chicken gonads

    PubMed Central

    de Melo Bernardo, Ana; Heeren, A. Marijne; van Iperen, Liesbeth; Fernandes, Maria Gomes; He, Nannan; Anjie, Stafford; Noce, Toshiaki; Ramos, Ester Silveira

    2015-01-01

    SUMMARY Development of female gonads in the chicken is asymmetric. This asymmetry affects gene expression, morphology, and germ cell development; consequently only the left ovary develops into a functional organ, whereas the right ovary remains vestigial. In males, on the other hand, both gonads develop into functional testes. Here, we revisited the development of asymmetric traits in female (and male) chicken gonads between Hamburger Hamilton stage 16 (HH16) and hatching. At HH16, primordial germ cells migrated preferentially to the left gonad, accumulating in the left coelomic hinge between the gut mesentery and developing gonad in both males and females. Using the meiotic markers SYCP3 and phosphorylated H2AFX, we identified a previously undescribed, pronounced asymmetryc meiotic progression in the germ cells located in the central, lateral, and extreme cortical regions of the left female gonad from HH38 until hatching. Moreover, we observed that—in contrast to the current view—medullary germ cells are not apoptotic, but remain arrested in pre‐leptotene until hatching. In addition to the systematic analysis of the asymmetric distribution of germ cells in female chicken gonads, we propose an updated model suggesting that the localization of germ cells—in the left or right gonad; in the cortex or medulla of the left gonad; and in the central part or the extremities of the left cortex—has direct consequences for their development and participation in adult reproduction. Mol. Reprod. Dev. 82: 774–786, 2015. © 2015 The Authors. Molecular Reproduction and Development published by Wiley Periodicals, Inc. PMID:26096940

  2. Effect of a mercurial fungicide on the gonadal development of the teleostean fish Channa punctatus (Bloch).

    PubMed

    Ram, R N; Sathyanesan, A G

    1986-06-01

    Channa punctatus exposed to a "safe" concentration of 0.20 ppm of a commercial mercurial fungicide, Emisan (MeEHgCl), for 6 months, from January to June, exhibited significant inhibition of gonadal development as evidenced by their histology and reduced gonadosomatic index. Degenerative changes were also evident. Correlative histological changes were also noted in the pituitary gonadotrophs which were reduced in the exposed fish. Several stage I oocytes exhibited proteinaceous extra and intranuclear "inclusion bodies," and intranuclear "ring-like bodies" associated with the ultimate degeneration of the oocytes. These observations suggest that MeEHgCl inhibits gonadal development through the hypothalamic-pituitary-gonadal axis in this species.

  3. Proteomic dataset of Paracentrotus lividus gonads of different sexes and at different maturation stages.

    PubMed

    Ghisaura, Stefania; Loi, Barbara; Biosa, Grazia; Baroli, Maura; Pagnozzi, Daniela; Roggio, Tonina; Uzzau, Sergio; Anedda, Roberto; Addis, Maria Filippa

    2016-09-01

    We report the proteomic dataset of gonads from wild Paracentrotus lividus related to the research article entitled "Proteomic changes occurring along gonad maturation in the edible sea urchin Paracentrotus lividus" [1]. Gonads of three individuals per sex in the recovery, pre-mature, mature, and spent stages were analyzed using a shotgun proteomics approach based on filter-aided sample preparation followed by tandem mass spectrometry, protein identification carried out using Sequest-HT as the search engine within the Proteome Discoverer informatics platform, and label-free differential analysis. The dataset has been deposited in the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PRIDE: PXD004200.

  4. H-Y antigen in Swyer syndrome and the genetics of XY gonadal dysgenesis.

    PubMed

    Moreira-Filho, C A; Toledo, S P; Bagnolli, V R; Frota-Pessoa, O; Bisi, H; Wajntal, A

    1979-01-01

    The H-Y antigen is a plasma membrane antigen involved in the organogenesis of the mammalian testis. Its expression on human cells is determined by a Y-linked gene. Phenotypic females affected by 46,XY gonadal dysgenesis (Swyer's syndrome) can be either H-Y-positive or H-Y-negative. In this paper we report H-Y antigen and endocrine studies in a sibship with three affected sisters. Immunological studies were performed on two of the patients, and a clearly positive expression was detected in both cases. Endocrine studies consisted in the investigation of the hypothalamic-pituitary-gonadal axis, which revealed that gonadal hormone insufficiency is the only endocrine abnormality associated with the syndrome. A new genetic interpretation and calssification of XY gonadal dysgenesis is proposed.

  5. A brief history of the pathology of the gonads.

    PubMed

    Young, Robert H

    2005-02-01

    Our understanding of gonadal pathology has reached its current state as a result of the contributions of numerous outstanding investigators. Knowledge of testicular tumor pathology dates back to the great British workers Percival Pott and Sir Astley Cooper but the single greatest early stride was made with the description in 1906 by the French urologist Maurice Chevassu of the seminoma. The seminal 1946 paper of Nathan B Friedman and Robert A Moore, which segregated out as a distinct entity embryonal carcinoma, is, however, the foundation for the current classification of testicular tumors. In that year Pierre Masson described the distinctive neoplasm, the spermatocytic seminoma. The 1950s saw the publication of an important paper by Frank J Dixon and Dr Moore and they also wrote the first series fascicle on testicular tumors. In this same timeframe, and thereafter, Robert E Scully made significant contributions to testicular pathology, writing the first English language paper on spermatocytic seminoma, describing several subtypes of sex cord tumor, and also the distinctive lesion of intersex, the gonadoblastoma, as well as playing a major role in 1980 in formulating the current classification of premalignant lesions of the testis. The current classification of testicular tumors was arrived at in the early 1970s when the World Health Organization, under the leadership of Dr FK Mostofi, who himself made notable contributions to testicular pathology, devised what is fundamentally the current classification of neoplasms of the male gonad. Although comments on ovarian pathology were made by such legendary figures of earlier times as Giovanni Battista Morgagni and Matthew Baillie, it is only in the mid to later years of the 19th century that contributions, mostly in Europe, began to move knowledge of ovarian pathology to its current state. Thomas Hodgkin, Richard Bright, and Sir James Paget all wrote extensively on ovarian neoplasms. In 1870, Heinrich Waldeyer, and

  6. Starfish gonadotropic hormone: Relaxin-like gonad-stimulating peptides.

    PubMed

    Mita, Masatoshi

    2016-05-01

    Relaxin-like gonad-stimulating peptide (RGP) of starfish Patiria (= Asterina) pectinifera is the first identified invertebrate gonadotropin to trigger final gamete maturation. Recently, chemical structures of RGP were identified in several species of starfish. Three kinds of RGP molecules are found in the class Asteroidea. The chemical structure of P. pectinifera RGP (PpeRGP) is conserved among starfish of the order Valvatida beyond species. In contrast, the chemical structures of RGP identified in Asterias amurensis and Aphelasterias japonica of the order Forcipulatida are quite different from that of PpeRGP. The chemical structure of RGP in A. amurensis (AamRGP) is exactly the same as that in Asterias rubens (the order Forcipulatida), Astropecten scoparius (the order Paxillosida), Astropecten polyacanthus (the order Paxillosida), and Echinaster luzonicus (the order Spinulosida). The chemical structure of Coscinasterias acutispina RGP (the order Forcipulatida) is consistent with that of A. japonica RGP (AjaRGP). In cross-experiments using P. pectinifera, A. amurensis, and A. japonica ovaries, AamRGP and AjaRGP can induce each species of ovaries. Neither AamRGP nor AjaRGP induce oocyte maturation and ovulation in the ovary of P. pectinifera, although the PpeRGP is active in ovaries of A. amurensis and A. japonica. This suggests that the AamRGP and AjaRGP partly act species specificity.

  7. Plasma adrenal and gonadal sex steroids in human pubertal development.

    PubMed

    Ducharme, J R; Forest, M G; De Peretti, E; Sempé, M; Collu, R; Bertrand, J

    1976-03-01

    Plasma free dehydroepiandrosterone (DHA), androstenedione (delta), testosterone (T), dihydrotestosterone (DHT), estrone (E1), and estradiol (E2) were measured by radioimmunoassay in 55 boys and 54 girls 3.5 to 16.3 years of age. Plasma DHA increased significantly between 6 and 8 years of age in girls and between 8 and 10 years of age in boys. A further significant increase was noted between 10 and 12 years of age in both sexes. Delta rose significantly between 8 and 10 years of age in girls and between 10 and 12 years in boys. In contrast, no significant increase in T, DHT, or E1, was noted prior to 12 years of age in both sexes. However, E2 showed a significant increase between 10 and 12 years of age in girls. This early rise in the course of pubertal development of the two sex steroids predominantly of adrenal origin, DHA and delta, and its occurence 1 to 2 years earlier in girls than in boys, as does puberty itself, suggest a possible role for these steroids in the mechanisms involved in triggering the hypothalamic-pituitary-gonadal axis at puberty.

  8. Molecular regulation of hypothalamus-pituitary-gonads axis in males.

    PubMed

    Jin, Jia-Min; Yang, Wan-Xi

    2014-11-01

    The hypothalamic-pituitary-gonadal axis (HPG) plays vital roles in reproduction and steroid hormone production in both sexes. The focus of this review is upon gene structures, receptor structures and the signaling pathways of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The hormones' functions in reproduction as well as consequences resulting from mutations are also summarized. Specific characteristics of hormones such as the pulsatile secretions of GnRH are also covered. The different regulators of the HPG axis are introduced including kisspeptin, activin, inhibin, follistatin, androgens and estrogen. This review includes not only their basic information, but also their unique function in the HPG axis. Here we view the HPG axis as a whole, so relations between ligands and receptors are well described crossing different levels of the HPG axis. Hormone interactions and transformations are also considered. The major information of this article is depicted in three figures summarizing the current discoveries on the HPG axis. This article systematically introduces the basic knowledge of the HPG axis and provides information of the current advances relating to reproductive hormones.

  9. Hypothalamic-pituitary-gonadal function in anorexia nervosa and bulimia.

    PubMed

    Devlin, M J; Walsh, B T; Katz, J L; Roose, S P; Linkie, D M; Wright, L; Vande Wiele, R; Glassman, A H

    1989-04-01

    Patients with anorexia nervosa (AN) exhibit neuroendocrine abnormalities that may result solely from emaciation or may reflect defective endocrine mechanisms which are intrinsic to disordered eating even in the absence of starvation. To distinguish these possibilities, we have studied indices of hypothalamic-pituitary-gonadal (HPG) function in 9 patients with AN, 12 normal weight patients with bulimia and recent or current oligomenorrhea, and 8 normal weight controls. Measurement of 24-hour luteinizing hormone (LH) secretion with 30-min sampling revealed significantly fewer LH secretory spikes and a trend toward lower mean 24-hour LH levels in both bulimic and anorectic patients than in controls. Stimulation with gonadotropin releasing hormone produced elevated LH responses in the bulimic group and blunted LH responses in the anorectic group. Stimulation with estradiol revealed diminished LH augmentative responses and a trend toward diminished follicle stimulating hormone augmentative responses among bulimic as well as AN patients compared to controls. In each instance, the bulimic group tended to show within-group heterogeneity, with some individuals falling within the AN range. These findings suggest that HPG axis abnormalities in eating disordered patients cannot entirely be attributed to emaciation and that factors other than subnormal weight contribute to disturbed hypothalamic-pituitary functioning in these patients.

  10. Thymic regulation of the hypothalamic-pituitary-gonadal axis.

    PubMed

    Hall, N R; O'Grady, M P; Menzies, R A

    1992-04-01

    The thymus gland and the cells that it regulates produce a number of soluble factors that are capable of indirectly modulating the immune system via reproductive neuroendocrine circuits. Studies dating to the turn of the century were designed to evaluate the effects of partially purified thymic extracts in treating various reproductive disorders as well as changes in gonadal tissue weights. More recent studies have focused on the chemical nature of the factors responsible for regulating reproductive function. A number of factors have been described. These include thymosin beta 4 which has been found to stimulate the release of luteinizing hormone releasing hormone and luteinizing hormone (LH). Other factors such as interleukin-1 (IL-1) have been found to inhibit the release of these two peptides. IL-1 has also been found to alter the expression of LH receptors in rat granulosa cells. Certain interferons have been found capable of suppressing estrogen and progesterone release. While many of the studies have been carried out using adult animal models, there is increasing evidence that exposure to cytokines during early development can have long lasting if not permanent effects upon the reproductive axis. These and related topics are the subject of this review.

  11. Hypothalamic-pituitary-gonadal axis homeostasis predicts longevity.

    PubMed

    Yonker, James A; Chang, Vicky; Roetker, Nicholas S; Hauser, Taissa S; Hauser, Robert M; Atwood, Craig S

    2013-02-01

    The reproductive-cell cycle theory of aging posits that reproductive hormone changes associated with menopause and andropause drive senescence via altered cell cycle signaling. Using data from the Wisconsin Longitudinal Study (n = 5,034), we analyzed the relationship between longevity and menopause, including other factors that impact "ovarian lifespan" such as births, oophorectomy, and hormone replacement therapy. We found that later onset of menopause was associated with lower mortality, with and without adjusting for additional factors (years of education, smoking status, body mass index, and marital status). Each year of delayed menopause resulted in a 2.9% reduction in mortality; after including a number of additional controls, the effect was attenuated modestly but remained statistically significant (2.6% reduction in mortality). We also found that no other reproductive parameters assessed added to the prediction of longevity, suggesting that reproductive factors shown to affect longevity elsewhere may be mediated by age of menopause. Thus, surgical and natural menopause at age 40, for example, resulted in identical survival probabilities. These results support the maintenance of the hypothalamic-pituitary-gonadal axis in homeostasis in prolonging human longevity, which provides a coherent framework for understanding the relationship between reproduction and longevity.

  12. Modeling the brain-pituitary-gonad axis in salmon

    SciTech Connect

    Kim, Jonghan; Hayton, William L.; Schultz, Irv R.

    2006-08-24

    To better understand the complexity of the brain-pituitary-gonad axis (BPG) in fish, we developed a biologically based pharmacodynamic model capable of accurately predicting the normal functioning of the BPG axis in salmon. This first-generation model consisted of a set of 13 equations whose formulation was guided by published values for plasma concentrations of pituitary- (FSH, LH) and ovary- (estradiol, 17a,20b-dihydroxy-4-pregnene-3-one) derived hormones measured in Coho salmon over an annual spawning period. In addition, the model incorporated pertinent features of previously published mammalian models and indirect response pharmacodynamic models. Model-based equations include a description of gonadotropin releasing hormone (GnRH) synthesis and release from the hypothalamus, which is controlled by environmental variables such as photoperiod and water temperature. GnRH stimulated the biosynthesis of mRNA for FSH and LH, which were also influenced by estradiol concentration in plasma. The level of estradiol in the plasma was regulated by the oocytes, which moved along a maturation progression. Estradiol was synthesized at a basal rate and as oocytes matured, stimulation of its biosynthesis occurred. The BPG model can be integrated with toxico-genomic, -proteomic data, allowing linkage between molecular based biomarkers and reproduction in fish.

  13. A brief history of the pathology of the gonads.

    PubMed

    Young, Robert H

    2005-02-01

    Our understanding of gonadal pathology has reached its current state as a result of the contributions of numerous outstanding investigators. Knowledge of testicular tumor pathology dates back to the great British workers Percival Pott and Sir Astley Cooper but the single greatest early stride was made with the description in 1906 by the French urologist Maurice Chevassu of the seminoma. The seminal 1946 paper of Nathan B Friedman and Robert A Moore, which segregated out as a distinct entity embryonal carcinoma, is, however, the foundation for the current classification of testicular tumors. In that year Pierre Masson described the distinctive neoplasm, the spermatocytic seminoma. The 1950s saw the publication of an important paper by Frank J Dixon and Dr Moore and they also wrote the first series fascicle on testicular tumors. In this same timeframe, and thereafter, Robert E Scully made significant contributions to testicular pathology, writing the first English language paper on spermatocytic seminoma, describing several subtypes of sex cord tumor, and also the distinctive lesion of intersex, the gonadoblastoma, as well as playing a major role in 1980 in formulating the current classification of premalignant lesions of the testis. The current classification of testicular tumors was arrived at in the early 1970s when the World Health Organization, under the leadership of Dr FK Mostofi, who himself made notable contributions to testicular pathology, devised what is fundamentally the current classification of neoplasms of the male gonad. Although comments on ovarian pathology were made by such legendary figures of earlier times as Giovanni Battista Morgagni and Matthew Baillie, it is only in the mid to later years of the 19th century that contributions, mostly in Europe, began to move knowledge of ovarian pathology to its current state. Thomas Hodgkin, Richard Bright, and Sir James Paget all wrote extensively on ovarian neoplasms. In 1870, Heinrich Waldeyer, and

  14. Germ Cell Nuclear Factor Regulates Gametogenesis in Developing Gonads

    PubMed Central

    Sabour, Davood; Xu, Xueping; Chung, Arthur C. K.; Le Menuet, Damien; Ko, Kinarm; Tapia, Natalia; Araúzo-Bravo, Marcos J.; Gentile, Luca; Greber, Boris; Hübner, Karin; Sebastiano, Vittorio; Wu, Guangming; Schöler, Hans R.; Cooney, Austin J.

    2014-01-01

    Expression of germ cell nuclear factor (GCNF; Nr6a1), an orphan member of the nuclear receptor gene family of transcription factors, during gastrulation and neurulation is critical for normal embryogenesis in mice. Gcnf represses the expression of the POU-domain transcription factor Oct4 (Pou5f1) during mouse post-implantation development. Although Gcnf expression is not critical for the embryonic segregation of the germ cell lineage, we found that sexually dimorphic expression of Gcnf in germ cells correlates with the expression of pluripotency-associated genes, such as Oct4, Sox2, and Nanog, as well as the early meiotic marker gene Stra8. To elucidate the role of Gcnf during mouse germ cell differentiation, we generated an ex vivo Gcnf-knockdown model in combination with a regulated CreLox mutation of Gcnf. Lack of Gcnf impairs normal spermatogenesis and oogenesis in vivo, as well as the derivation of germ cells from embryonic stem cells (ESCs) in vitro. Inactivation of the Gcnf gene in vivo leads to loss of repression of Oct4 expression in both male and female gonads. PMID:25140725

  15. P450 aromatase expression in the temperature-sensitive sexual differentiation of salamander (Hynobius retardatus) gonads.

    PubMed

    Sakata, Natsuko; Tamori, Yoichiro; Wakahara, Masami

    2005-01-01

    Sex differentiation of gonads in amphibians is believed to be controlled genetically, but altered epigenetically or environmentally. When larvae of the salamander Hynobius retardatus were reared at defined temperatures from hatching to metamorphic stages, a high temperature (28 degrees C) induced exclusively female gonads (ovaries), whereas intermediate (20 and 23 degrees C) or lower (16 degrees C) temperatures produced a 1:1 sex ratio of the morphological gonads. The thermosensitive period was determined to be restricted from 15 to 30 days after hatching, just before or when sexual differentiation occurred. Hynobius P450 aromatase (P450arom) cDNA was isolated from adult gonads and the partial nucleotide or deduced amino acid sequences were determined, showing a high level of identity with various vertebrate species. The P450arom gene was expressed predominantly in the adult ovary and brain, weakly in testis, but not in other somatic organs. A typical sexual dimorphism in P450arom expression was detected in normally developing larvae by a quantitative competitive RT-PCR; strong expression in the female gonads but very weak in male gonads. The dimorphism was detected much earlier than the morphological sexual differentiation of the gonads. When larvae were reared at the female-producing temperature (28 degrees C), strong expression was detected in all the temperature-treated larvae, suggesting that P450arom was up-regulated, even in genetic males. Our results confirm the importance of the P450arom regulation in the sexual differentiation of gonads and demonstrate that an up-regulation of P450arom is involved in the process of temperature-sensitive sex reversal in this species.

  16. Sex and alcohol: the effects of alcohol on the hypothalamic-pituitary-gonadal axis.

    PubMed

    Greene, L W; Hollander, C S

    1980-01-01

    Effects of alcohol on the hypothalamic-pituitary-gonadal axis are complex. Those at the gonadal level are best defined in studies such as those presented in this issue. However, there is an accumulating body of data supporting central effects of alcohol. The precise locus or loci is not certain. Further investigations probably including in vitro methodologies are likely to enhance our knowledge in this area. Our understanding of the effects of alcohol in the human female is especially limited.

  17. Development of the mesonephros, metanephros and gonads in the foetal dog.

    PubMed

    Salazar, I; Yllera, M M

    1991-01-01

    We describe the chronology of the development of the renal system and gonads of 19 greyhound foetuses. The smallest specimens were embedded in paraffin wax and were sectioned serially at 10 microns; the rest were sectioned at 50 microns in an LKB 2250 PMV cryomicrotome. Selected sections were stained with haematoxylin and eosin. The mesonephros, metanephros and gonads were measured in drawings of the sections, using the area fraction programme of a Vids II image analyse.

  18. Clinical Features of 32 Patients with XO/XY Gonadal Dysgenesis.

    PubMed

    Jiang, Jian-Fa; Tian, Qin-Jie; Xue, Wei; Deng, Yan; Zheng, Ting-Ping; Sun, Ai-Jun

    2016-08-01

    Objective To summarize the clinical features of XO/XY gonadal dysgenesis. Method We retrospectively analyzed the clinical data of patients with XO/XY gonadal dysgenesis admitted to Peking Union Medical College Hospital from January 2008 to May 2015. Results Totally 32 patients with XO/XY gonadal dysgenesis were included. The social gender was female in all subjects and the age 6 to 33 years. Patients presented mainly with primary amenorrhea or short stature,and usually had specific somatic signs of Turner's syndrome. The breast development of 27 patients (84.38%) was less than level 3. The armpit hair was sparse or absent in 28 patients (87.5%) and the pubic hair was sparse or absent in 26 patients (81.25%).Other findings include naive vulva (n=18,56.25%)) and enlarged clitoris (n=5,15.63%). The average level of follicle stimulating hormone was (78.56±35.62) mIU/ml,the luteinizing hormone level was (20.23±11.35) mIU/ml,the estradiol level was (9.94±8.21) pg/ml,and the testosterone level was (0.24±0.18) ng/ml. All patients received prophylactic gonadectomy. The histopathology results showed a variety of gonads,and gonadal malignancy were observed in 4 patients.Conclusions Patients with XO/XY gonadal dysgenesis manifest primary amenorrhea or short stature,poorly developed secondary sexual characteristics,and elevated gonadotropin level. The gonads have increased risk of gonadal malignancy. PMID:27594153

  19. Prenatal melatonin and its interaction with tachykinins in the hypothalamic-pituitary-gonadal axis.

    PubMed

    Díaz López, B; Debeljuk, L

    2007-01-01

    The pineal gland, through its hormone melatonin, influences the function of the hypothalamic-pituitary-gonadal axis. Tachykinins are bioactive peptides whose presence has been demonstrated in the pineal gland, hypothalamus, anterior pituitary gland and the gonads, in addition to other central and peripheral structures. Tachykinins have been demonstrated to influence the function of the hypothalamic-pituitary-gonadal axis, acting as paracrine factors at each of these levels. In the present review, we examine the available evidence supporting a role for melatonin in the regulation of reproductive functions, the possible role of tachykinins in pineal function and the possible interactions between melatonin and tachykinins in the hypothalamic-pituitary-gonadal axis. Evidence is presented showing that melatonin, given to pregnant rats, influences the developmental pattern of tachykinins in the hypothalamus and the anterior pituitary gland of the offspring during postnatal life. In the gonads, the effects of melatonin on the tachykinin developmental pattern were rather modest. In particular, in the present review, we have included a summary of our own work performed in the past few years on the effect of melatonin on tachykinin levels in the hypothalamic-pituitary-gonadal axis.

  20. Differential effects of testosterone and 17β-estradiol on gonadal development in five anuran species.

    PubMed

    Piprek, Rafał P; Pecio, Anna; Kubiak, Jacek Z; Szymura, Jacek M

    2012-08-01

    Sex hormones are essential for sexual differentiation and play a key role in the development of gonads in amphibians. The goal of this study was to evaluate the influence of exogenous sex steroids, testosterone, and 17β-estradiol (E(2)) on development of gonads in five anuran species differing in their evolutionary positions, sex determination, and mode of gonadogenesis. We found that in two closely related species of fire-bellied toad, Bombina bombina and Bombina variegata, testosterone and E(2) exposure results in sex reversal as well as intersex and undifferentiated gonads. Similarly, sex reversal was observed in Hyla arborea after exposure to male or female sex steroids. Xenopus laevis was sensitive to E(2) but only moderately to testosterone. In Bufo viridis, treatment with either sex hormone provoked a developmental delay in gonads and Bidder's organs. Therefore, susceptibility to hormonal sex reversal appeared species dependent but unrelated to genetic sex determination and the type of gonadogenesis. We also found that the onset of sex steroid exposure influences gonad differentiation and the meiotic status of the germ cells depends on their location within the gonad. Our findings reveal differential sensitivity of amphibians to testosterone and E(2), establishing a hierarchy of sensitivity to these hormones among different anuran species.

  1. Microanatomical Study of Embryonic Gonadal Development in Japanese Quail (Coturnix japonica).

    PubMed

    Intarapat, Sittipon; Satayalai, Orawan

    2014-01-01

    Gonadal development of quail embryos was examined histologically using histological and histochemical methods. In the present study, quail embryos were studied at various stages of incubation period based on phases of gonadogenesis. Germ cell migration was observed on day 3-4 but gonadal differentiation and gonadal function were observed on day 6-8 and day 11-14, respectively. During germ cell migration, quail primordial germ cells (qPGCs) were successfully detected in both left and right genital ridges as well as the dorsal mesentery by lectin histochemistry. Unexpectedly, qPGCs-like cells were found next to the neural tube by Mallory-AZAN stain. During gonadal differentiation, embryonic sex can be distinguished histologically since day 8 of incubation. Embryonic testis exhibited a thin cortex, whereas embryonic ovary exhibited a thick cortex. Testicular cord formation was found in the medulla of embryonic testes while the lacunae and fat-laden cells were found in the medulla of embryonic ovary during gonadal function. This is the first report on a comparison of phases of gonadogenesis and histochemical study of quail embryonic gonads in both sexes. PMID:25276431

  2. Relaxin-3 stimulates the hypothalamic-pituitary-gonadal axis.

    PubMed

    McGowan, B M; Stanley, S A; Donovan, J; Thompson, E L; Patterson, M; Semjonous, N M; Gardiner, J V; Murphy, K G; Ghatei, M A; Bloom, S R

    2008-08-01

    The hypothalamus plays a key role in the regulation of both energy homeostasis and reproduction. Evidence suggests that relaxin-3, a recently discovered member of the insulin superfamily, is an orexigenic hypothalamic neuropeptide. Relaxin-3 is thought to act in the brain via the RXFP3 receptor, although the RXFP1 receptor may also play a role. Relaxin-3, RXFP3, and RXFP1 are present in the hypothalamic paraventricular nucleus, an area with a well-characterized role in the regulation of energy balance that also modulates reproductive function by providing inputs to hypothalamic gonadotropin-releasing hormone (GnRH) neurons. Other members of the relaxin family are known to play a role in the regulation of reproduction. However, the effects of relaxin-3 on reproductive function are unknown. We studied the role of relaxin-3 in the regulation of the hypothalamo-pituitary-gonadal (HPG) axis. Intracerebroventricular (5 nmol) and intraparaventricular (540-1,620 pmol) administration of human relaxin-3 (H3) in adult male Wistar rats significantly increased plasma luteinizing hormone (LH) 30 min postinjection. This effect was blocked by pretreatment with a peripheral GnRH antagonist. Central administration of human relaxin-2 showed no significant effect on plasma LH. H3 dose-dependently stimulated the release of GnRH from hypothalamic explants and GT(1)-7 cells, which express RXFP1 and RXFP3, but did not influence LH or follicle-stimulating hormone release from pituitary fragments in vitro. We have demonstrated a novel role for relaxin-3 in the stimulation of the HPG axis, putatively via hypothalamic GnRH neurons. Relaxin-3 may act as a central signal linking nutritional status and reproductive function.

  3. Gonadal status in male survivors following childhood brain tumors.

    PubMed

    Schmiegelow, M; Lassen, S; Poulsen, H S; Schmiegelow, K; Hertz, H; Andersson, A M; Skakkebaek, N E; Müller, J

    2001-06-01

    The effect of radiotherapy (RT) and chemotherapy (CT) on gonadal function was assessed in males treated for a childhood brain tumor not directly involving the hypothalamus/pituitary (HP) axis in a population-based study with a long follow-up time. All males <15 yr at the time of diagnosis (median: 9.0 yr, range: 0.8 to 14.9 yr) and diagnosed from January 1970 through February 1997 in the eastern part of Denmark and [gte]18 yr at the time of follow-up (median: 25.8 yr, range:18.5 to 39.3 yr) were included. Thirty males fulfilled the criteria. The median age at time of RT was 9.0 yr (range: 0.8 to 14.9 yr) and the median length of follow-up was 18 yr (range: 2.0 to 28.0 yr). The biological effective dose of RT was determined to the HP region and to the spine and expressed in gray because the biological effective dose gives a means of expressing the biological effect on normal tissue of different dosage schedules in a uniform way. Levels of serum FSH, luteinizing hormone (LH), sexual hormone-binding globulin, testosterone, and inhibin B were measured and compared with healthy age-matched male controls (n = 347), and the patients had a GnRH stimulation test performed with determination of peak FSH and LH. Patients treated with RT + CT (n = 13), compared with patients treated with RT only (n = 17), had significantly higher median peak FSH (8.33 vs. 3.79 IU/L, P = 0.03) and median peak LH (20.0 vs. 12.8 IU/L, P = 0.03), and significantly lower median inhibin B (86.0 vs. 270 pg/ml, P = 0.03), and median inhibin B/FSH ratio (12.8 vs. 107.9, P = 0.04), which indicates gonadal damage. Inhibin B and inhibin B/FSH ratio were also significantly lower in the RT + CT group, compared with controls (median: 86.0 vs. 215 pg/ml, P = 0.02), (median:12.8 vs. 67; P = 0.01), respectively. We found a significantly inverse correlation between basal FSH and inhibin B and FSH and total testicular volume (r(s) = -0.83; P < 0.0001), (r(s) = -0.67; P < 0.0001), respectively, and a significant

  4. Embryonic testicular regression sequence: A part of the clinical spectrum of 46,XY gonadal dysgenesis

    SciTech Connect

    Marcantonio, S.M.; Fechner, P.Y.; Migeon, C.J.; Perlman, E.J.; Berkovitz, G.D.

    1994-01-01

    The authors report on a group of 9 subjects who had a 46,XY karyotype, ambiguous genitalia, abnormalities of sexual duct formation, and lack of gonadal tissue on one or both sides. This is sometimes referred to as {open_quotes}embryonic testicular regression.{close_quotes} Previous investigators have suggested that this condition results from loss of testes at a critical stage in development. The authors examined the possibility that embryonic testicular regression is part of the clinical spectrum of 46,XY gonadal dysgenesis. Four subjects totally lacked gonadal tissue, three of them having ambiguous genitalia, and one a micropenis. The development of incongruous sexual ducts (presence of Muellerian ducts in the subject with micropenis, and absence of Muellerian and Wolffian ducts in two subjects with ambiguous genitalia) suggests that the embryonic gonads were intrinsically functionally abnormal before their disappearance. Five subjects had unilateral gonadal tissue, ambiguous genitalia, and a mix of Wolffian and Muellerian structures. The development of incongruous sexual ducts in 3 of them, the presence of ambiguous external genitalia in 5, and the presence of abnormal gonadal histology in 2 patients all indicate an underlying abnormality of gonadal differentiation in these subjects. The occurrence of testicular regression in several subjects in the family of one patient suggests a genetic basis for the condition. The presence of multiple congenital anomalies in other subjects in the study suggests either a mutation in a single gene that functions in several developmental pathways, or a defect of multiple genes that might be the result of a chromosome deletion. The sex-determining region Y (SRY) gene was sequenced in five subjects and was normal in all of them, suggesting that the underlying genetic abnormality in these subjects is located in one of several genes that function subsequent to SRY in the early stages of testis differentiation. 37 refs., 2 tabs.

  5. Discovery and identification of candidate sex-related genes based on transcriptome sequencing of Russian sturgeon (Acipenser gueldenstaedtii) gonads.

    PubMed

    Chen, Yadong; Xia, Yongtao; Shao, Changwei; Han, Lei; Chen, Xuejie; Yu, Mengjun; Sha, Zhenxia

    2016-07-01

    As the Russian sturgeon (Acipenser gueldenstaedtii) is an important food and is the main source of caviar, it is necessary to discover the genes associated with its sex differentiation. However, the complicated life and maturity cycles of the Russian sturgeon restrict the accurate identification of sex in early development. To generate a first look at specific sex-related genes, we sequenced the transcriptome of gonads in different development stages (1, 2, and 5 yr old stages) with next-generation RNA sequencing. We generated >60 million raw reads, and the filtered reads were assembled into 263,341 contigs, which produced 38,505 unigenes. Genes involved in signal transduction mechanisms were the most abundant, suggesting that development of sturgeon gonads is under control of signal transduction mechanisms. Differentially expressed gene analysis suggests that more genes for protein synthesis, cytochrome c oxidase subunits, and ribosomal proteins were expressed in female gonads than in male. Meanwhile, male gonads expressed more transposable element transposase, reverse transcriptase, and transposase-related genes than female. In total, 342, 782, and 7,845 genes were detected in intersex, male, and female transcriptomes, respectively. The female gonad expressed more genes than the male gonad, and more genes were involved in female gonadal development. Genes (sox9, foxl2) are differentially expressed in different sexes and may be important sex-related genes in Russian sturgeon. Sox9 genes are responsible for the development of male gonads and foxl2 for female gonads.

  6. Gonadoblastoma and selected other aspects of gonadal pathology in young patients with disorders of sex development.

    PubMed

    Ulbright, Thomas M; Young, Robert H

    2014-09-01

    Some patients with disorders of sex development (DSDs), previously known as intersex disorders, have abnormal gonadal development and an increased risk of germ cell tumors. Because of their relative rarity, however, many pathologists are unfamiliar with the morphological findings in the gonads of DSD patients and their clinical significance. This review concentrates on some of the most common DSDs where gonadal specimens may come to the attention of pathologists. It highlights the findings in gonadal dysgenesis, a DSD with a spectrum of clinical, pathologic, and molecular features but with the shared attributes of having both Y chromosomal material (even if in very limited amounts) in the gonad and also having mutations or deletions in genes necessary for normal gonadal development, mostly in those upstream of the SOX9 gene. This situation results in testicular tissue lacking normal Sertoli cells, which are now considered an essential element for the normal maturation of the primordial germ cells that migrate to the gonad from the embryonic yolk sac. Germ cells with delayed maturation mimic neoplastic germ cells, but there are both morphological and immunohistochemical differences. If the gonad having germ cells with delayed maturation also harbors the TSPY gene on the GBY locus of the Y chromosome, the cells may undergo neoplastic transformation and result in the distinctive gonadoblastoma, whose pathologic features are explored at length herein, including its potential for variant morphologies, such as a "dissecting" pattern. Another important DSD, the androgen insensitivity syndrome (AIS), is discussed at length, including the varied appearances of the testis and its distinctive lesions-hamartomas and Sertoli cell adenomas. The potential for germ cell neoplasia in the partial AIS is also discussed and contrasted with that of the complete AIS. A third major topic is ovotesticular DSD (true hermaphroditism). The clinical features and morphology of this condition

  7. Hypothalamic-pituitary-gonadal axis in the mutant weaver mouse.

    PubMed

    Schwartz, N B; Szabo, M; Verina, T; Wei, J; Dlouhy, S R; Won, L; Heller, A; Hodes, M E; Ghetti, B

    1998-12-01

    The weaver (wv) mutant mouse manifests severe locomotor defects, a deficiency in granule cells of the cerebellum, and cellular deficits in the midbrain dopaminergic system. The wv phenotype is associated with a missense mutation in the pore region of the G-protein-gated inwardly rectifying potassium channel, GIRK2. The homozygous male wv mouse is essentially infertile due to an inadequate level of sperm production. Females are fertile although they also manifest the neurological phenotype. Homozygotes of both sexes have reduced body weight. We have evaluated the hypothalamic-pituitary-gonadal axis in heterozygote and homozygote male and female wv mutants in comparison with wild-type controls. Testicular weight was significantly reduced in the homozygous males, due to degenerative changes of seminiferous epithelium. Serum and pituitary content of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin were normal in all groups, and the normal sex differences were noted (FSH and LH higher in males, prolactin higher in females). Pituitary growth hormone (GH) concentration was normal, with control and mutant males showing higher GH than females. Serum testosterone levels were normal in the mutants, as was testicular testosterone. Testicular alpha-inhibin content was mildly reduced, but high in proportion to testicular weight. The defect in spermatogenesis appeared predominantly in the postmeiotic stages. In situ hybridization was consistent with expression of some GIRK2 mRNA isoforms in seminiferous epithelium. There were no significant differences between genotypes in the levels of dopamine, dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid in the mediobasal and preoptic hypothalamic regions. Homovanillic acid levels in these two areas were, however, reduced in wv homozygotes compared to wild-type animals. In the light of normal pituitary hormone levels, normal hypothalamic monoamine concentrations and normal sex differences in

  8. Gonadal morphogenesis and gene expression in reptiles with temperature-dependent sex determination.

    PubMed

    Merchant-Larios, H; Díaz-Hernández, V; Marmolejo-Valencia, A

    2010-01-01

    In reptiles with temperature-dependent sexual determination, the thermosensitive period (TSP) is the interval in which the sex is defined during gonadal morphogenesis. One-shift experiments in a group of eggs define the onset and the end of the TSP as all and none responses, respectively. Timing for sex-undetermined (UG) and -determined gonads (DG) differs at male- (MPT) or female-producing temperatures (FPT). During the TSP a decreasing number of embryos respond to temperature shifts indicating that in this period embryos with both UG and DG exist. Although most UG correspond to undifferentiated gonads, some embryos extend UG after the onset of histological differentiation. Thus, temperature affects gonadal cells during the process of morphogenesis, but timing of commitment depends on individual embryos. A correlation between gonadal morphogenesis, TSP, and gene expression suggests that determination of the molecular pathways modulated by temperature in epithelial cells (surface epithelium and medullary cords) holds the key for a unifying hypothesis on temperature-dependent sex determination.

  9. Studies on the functional relationship between thyroid, adrenal and gonadal hormones.

    PubMed

    Tohei, Atsushi

    2004-02-01

    In order to clarify the functional relationship between thyroid, adrenal and gonadal hormones, hypothyroidism was induced by administration of thiuoracil in adult male and female rats, and the effects of hypothyroidism on the adrenal and the gonadal axes were investigated in the present study. 1. The functional relationship between thyroid and adrenal hormones: Adrenal weights and corticosterone were lowered, whereas the secretion of ACTH, corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP) increased in hypothyroid rats compared to euthyroid rats. These results indicate that hypothyroidism causes adrenal dysfunction directly and results in hypersecretion of CRH and AVP from the hypothalamus. 2. The functional relationship between thyroid and gonadal hormones: The pituitary response to LHRH was lowered, whereas the testicular response to hCG was not changed in hypothyroid rats. Hypothyroidism suppressed copulatory behavior in male rats. These results suggest that hypothyroidism probably causes dysfunction in gonadal axis at the hypothalamic-pituitary level in male rats. In adult female rats, hypothyroidism inhibited the follicular development accompanied estradiol secretion, whereas plasma concentrations of progesterone and prolactin (PRL) increased in hypothyroid female rats. Hypothyroidism significantly increased the pituitary content of vasoactive intestinal peptide (VIP) though it did not affect dopamine synthesis. These results suggest that hypothyroidism increases pituitary content of VIP and this increased level of VIP likely affects PRL secretion in a paracrine or autocrine manner. In female rats, inhibition of gonadal function in hypothyroid rats mediated by hyperprolactinemia in addition to hypersecretion of endogenous CRH.

  10. The recreational drug ecstasy disrupts the hypothalamic-pituitary-gonadal reproductive axis in adult male rats.

    PubMed

    Dickerson, Sarah M; Walker, Deena M; Reveron, Maria E; Duvauchelle, Christine L; Gore, Andrea C

    2008-01-01

    Reproductive function involves an interaction of three regulatory levels: hypothalamus, pituitary, and gonad. The primary drive upon this system comes from hypothalamic gonadotropin-releasing hormone (GnRH) neurosecretory cells, which receive afferent inputs from other neurotransmitter systems in the central nervous system to result in the proper coordination of reproduction and the environment. Here, we hypothesized that the recreational drug (+/-)-3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy'), which acts through several of the neurotransmitter systems that affect GnRH neurons, suppresses the hypothalamic-pituitary-gonadal reproductive axis of male rats. Adult male Sprague-Dawley rats self-administered saline or MDMA either once (acute) or for 20 days (chronic) and were euthanized 7 days following the last administration. We quantified hypothalamic GnRH mRNA, serum luteinizing hormone concentrations, and serum testosterone levels as indices of hypothalamic, pituitary, and gonadal functions, respectively. The results indicate that the hypothalamic and gonadal levels of the hypothalamic-pituitary-gonadal axis are significantly altered by MDMA, with GnRH mRNA and serum testosterone levels suppressed in rats administered MDMA compared to saline. Furthermore, our finding that hypothalamic GnRH mRNA levels are suppressed in the context of low testosterone concentrations suggests that the central GnRH neurosecretory system may be a primary target of inhibitory regulation by MDMA usage.

  11. Characterization of the Epigenetic Changes During Human Gonadal Primordial Germ Cells Reprogramming.

    PubMed

    Eguizabal, C; Herrera, L; De Oñate, L; Montserrat, N; Hajkova, P; Izpisua Belmonte, J C

    2016-09-01

    Epigenetic reprogramming is a central process during mammalian germline development. Genome-wide DNA demethylation in primordial germ cells (PGCs) is a prerequisite for the erasure of epigenetic memory, preventing the transmission of epimutations to the next generation. Apart from DNA demethylation, germline reprogramming has been shown to entail reprogramming of histone marks and chromatin remodelling. Contrary to other animal models, there is limited information about the epigenetic dynamics during early germ cell development in humans. Here, we provide further characterization of the epigenetic configuration of the early human gonadal PGCs. We show that early gonadal human PGCs are DNA hypomethylated and their chromatin is characterized by low H3K9me2 and high H3K27me3 marks. Similarly to previous observations in mice, human gonadal PGCs undergo dynamic chromatin changes concomitant with the erasure of genomic imprints. Interestingly, and contrary to mouse early germ cells, expression of BLIMP1/PRDM1 persists in through all gestational stages in human gonadal PGCs and is associated with nuclear lysine-specific demethylase-1. Our work provides important additional information regarding the chromatin changes associated with human PGCs development between 6 and 13 weeks of gestation in male and female gonads. Stem Cells 2016;34:2418-2428. PMID:27300161

  12. The impact of adipose tissue-derived factors on the hypothalamic-pituitary-gonadal (HPG) axis.

    PubMed

    Tsatsanis, Christos; Dermitzaki, Eirini; Avgoustinaki, Pavlina; Malliaraki, Niki; Mytaras, Vasilis; Margioris, Andrew N

    2015-01-01

    Adipose tissue produces factors, including adipokines, cytokines and chemokines which, when released, systemically exert endocrine effects on multiple tissues thereby affecting their physiology. Adipokines also affect the hypothalamic-pituitary-gonadal (HPG) axis both centrally, at the hypothalamic-pituitary level, and peripherally acting on the gonads themselves. Among the adipokines, leptin, adiponectin, resistin, chemerin and the peptide kisspeptin have pleiotropic actions on the HPG axis affecting male and female fertility. Furthermore, adipokines and adipose tissue-produced factors readily affect the immune system resulting in inflammation, which in turn impact the HPG axis, thus evidencing a link between metabolic inflammation and fertility. In this review we provide an overview of the existing extensive bibliography on the crosstalk between adipose tissue-derived factors and the HPG axis, with particular focus on the impact of obesity and the metabolic syndrome on gonadal function and fertility.

  13. Suppression of serum gonadal steroids in rats by chronic treatment with dopamine and serotonin reuptake inhibitors.

    PubMed

    Rehavi, M; Attali, G; Gil-Ad, I; Weizman, A

    2000-05-01

    The impact of chronic administration (3 weeks) of dopamine and serotonin reuptake inhibitors on serum gonadal steroid hormones and prolactin was studied in intact male and female rats. Both the dopamine and the serotonin reuptake inhibitors lowered serum estradiol and progesterone levels in the female rats. The dopamine transporter blockers suppressed testosterone serum levels in the male rats, whereas serotonin reuptake inhibitors induced only a non-significant reduction (30%) of this hormone. In contrast to the decrease in gonadal steroids, none of the serotonin or the dopamine reuptake blockers altered prolactin serum levels in either the male or female rats. It seems that the effect of these agents on ovarian and testicular hormones is related to the impact of the monoamine reuptake inhibitors on the hypothalamic-pituitary-gonadal axis.

  14. Mixed gonadal dysgenesis in 45,X Turner syndrome with SRY gene.

    PubMed

    Jung, Jae Yeop; Yang, Sohyoung; Jeong, Eun-Hwan; Lee, Ho-Chang; Lee, Yong-Moon; Han, Heon-Seok; Yi, Kyung Hee

    2015-12-01

    Turner syndrome is the most common chromosomal disorder in girls. Various phenotypic features show depending upon karyotype from normal female through ambiguous genitalia to male. Usually, Turner girls containing 45,X/46,XY mosaicism, or sex-determining region Y (SRY) gene may have mixed gonadal dysgenesis with various external sexual differentiation. We experienced a short statured 45,X Turner girl with normal external genitalia. Because SRY gene was positive, laparoscopic gonadectomy was performed. The dysgenetic gonads revealed bilateral ovotesticular tissues. The authors report a mixed gonadal dysgenesis case found in clinical 45,X Turner patient with positive SRY gene. Screening for SRY gene should be done even the karyotype is 45,X monosomy and external genitalia is normal.

  15. Proteomic dataset of Paracentrotus lividus gonads of different sexes and at different maturation stages.

    PubMed

    Ghisaura, Stefania; Loi, Barbara; Biosa, Grazia; Baroli, Maura; Pagnozzi, Daniela; Roggio, Tonina; Uzzau, Sergio; Anedda, Roberto; Addis, Maria Filippa

    2016-09-01

    We report the proteomic dataset of gonads from wild Paracentrotus lividus related to the research article entitled "Proteomic changes occurring along gonad maturation in the edible sea urchin Paracentrotus lividus" [1]. Gonads of three individuals per sex in the recovery, pre-mature, mature, and spent stages were analyzed using a shotgun proteomics approach based on filter-aided sample preparation followed by tandem mass spectrometry, protein identification carried out using Sequest-HT as the search engine within the Proteome Discoverer informatics platform, and label-free differential analysis. The dataset has been deposited in the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PRIDE: PXD004200. PMID:27508229

  16. Mixed gonadal dysgenesis in 45,X Turner syndrome with SRY gene

    PubMed Central

    Jung, Jae Yeop; Yang, Sohyoung; Jeong, Eun-Hwan; Lee, Ho-Chang; Lee, Yong-Moon; Han, Heon-Seok

    2015-01-01

    Turner syndrome is the most common chromosomal disorder in girls. Various phenotypic features show depending upon karyotype from normal female through ambiguous genitalia to male. Usually, Turner girls containing 45,X/46,XY mosaicism, or sex-determining region Y (SRY) gene may have mixed gonadal dysgenesis with various external sexual differentiation. We experienced a short statured 45,X Turner girl with normal external genitalia. Because SRY gene was positive, laparoscopic gonadectomy was performed. The dysgenetic gonads revealed bilateral ovotesticular tissues. The authors report a mixed gonadal dysgenesis case found in clinical 45,X Turner patient with positive SRY gene. Screening for SRY gene should be done even the karyotype is 45,X monosomy and external genitalia is normal. PMID:26817010

  17. Recovery of gonadal development in tiger puffer Takifugu rubripes after exposure to 17β-estradiol during early life stages

    NASA Astrophysics Data System (ADS)

    Hu, Peng; Liu, Bin; Meng, Zhen; Liu, Xinfu; Jia, Yudong; Yang, Zhi; Lei, Jilin

    2016-06-01

    The aim of the present study was to investigate the long-term effects of 17β-estradiol (E2) exposure on gonadal development in the tiger puff er (Takifugu rubripes), which has a genetic sex determination system of male homogametic XY-XX. Tiger puff er larvae were exposed to 1, 10 and 100 μg/L E2 from 15 to 100 days post-hatch (dph) and then maintained in clean seawater until 400 dph. Changes in sex ratio, gonadal structure and gonadosomatic index (GSI) were monitored at 100, 160, 270 and 400 dph. Sex-associated single nucleotide polymorphism (SNP) markers were used to analyze the genetic sex of samples, except those at 100 dph. Exposure had a positive effect on the conversion of genetically male gonads into phenotypically female gonads at 100 dph. However, gonads from 60% of genetic XY males in the 1-μg/L E2 group and 100% in the 10-μg/L E2 group developed intersexual gonads at 160 dph; gonads of all genetic XY males in the two treatment groups reverted to testis by 270 dph. While 38%, 57% and 44% of gonads of XY fish in the 100-μg/L E2 group reverted to intersexual gonads at 160, 270 and 400 dph, respectively, none reverted to testis after E2 treatment. In addition, E2 exposure inhibited gonadal growth of both genetic sexes, as indicated by the clear dose-dependent decrease in GSI at 270 and 400 dph. The results showed that exposure to E2 during the early life stages of tiger puff er disrupted gonadal development, but that fish recovered after migration to clean seawater. The study suggests the potential use of tiger puff er as a valuable indicator species to evaluate the effects of environmental estrogens on marine fish, thereby protecting valuable fishery resources.

  18. Sex differences in diurnal rhythms of food intake in mice caused by gonadal hormones and complement of sex chromosomes.

    PubMed

    Chen, Xuqi; Wang, Lixin; Loh, Dawn H; Colwell, Christopher S; Taché, Yvette; Reue, Karen; Arnold, Arthur P

    2015-09-01

    We measured diurnal rhythms of food intake, as well as body weight and composition, while varying three major classes of sex-biasing factors: activational and organizational effects of gonadal hormones, and sex chromosome complement (SCC). Four Core Genotypes (FCG) mice, comprising XX and XY gonadal males and XX and XY gonadal females, were either gonad-intact or gonadectomized (GDX) as adults (2.5months); food intake was measured second-by-second for 7days starting 5weeks later, and body weight and composition were measured for 22weeks thereafter. Gonadal males weighed more than females. GDX increased body weight/fat of gonadal females, but increased body fat and reduced body weight of males. After GDX, XX mice had greater body weight and more fat than XY mice. In gonad-intact mice, males had greater total food intake and more meals than females during the dark phase, but females had more food intake and meals and larger meals than males during the light phase. GDX reduced overall food intake irrespective of gonad type or SCC, and eliminated differences in feeding between groups with different gonads. Diurnal phase of feeding was influenced by all three sex-biasing variables. Gonad-intact females had earlier onset and acrophase (peak) of feeding relative to males. GDX caused a phase-advance of feeding, especially in XX mice, leading to an earlier onset of feeding in GDX XX vs. XY mice, but earlier acrophase in GDX males relative to females. Gonadal hormones and SCC interact in the control of diurnal rhythms of food intake.

  19. The potential role of microRNAs in regulating gonadal sex differentiation in the chicken embryo.

    PubMed

    Cutting, Andrew D; Bannister, Stephanie C; Doran, Tim J; Sinclair, Andrew H; Tizard, Mark V L; Smith, Craig A

    2012-01-01

    Differential gene expression regulates tissue morphogenesis. The embryonic gonad is a good example, where the developmental decision to become an ovary or testis is governed by female- or male-specific gene expression. A number of genes have now been identified that control gonadal sex differentiation. However, the potential role of microRNAs (miRNAs) in ovarian and testicular pathways is unknown. In this review, we summarise our current understanding of gonadal differentiation and the possible involvement of miRNAs, using the chicken embryo as a model system. Chickens and other birds have a ZZ/ZW sex chromosome system, in which the female, ZW, is the heterogametic sex, and the male, ZZ, is homogametic (opposite to mammals). The Z-linked DMRT1 gene is thought to direct testis differentiation during embryonic life via a dosage-based mechanism. The conserved SOX9 gene is also likely to play a key role in testis formation. No master ovary determinant has yet been defined, but the autosomal FOXL2 and Aromatase genes are considered central. No miRNAs have been definitively shown to play a role in embryonic gonadal development in chickens or any other vertebrate species. Using next generation sequencing, we carried out an expression-based screen for miRNAs expressed in embryonic chicken gonads at the time of sexual differentiation. A number of miRNAs were identified, including several that showed sexually dimorphic expression. We validated a subset of miRNAs by qRT-PCR, and prediction algorithms were used to identify potential targets. We discuss the possible roles for these miRNAs in gonadal development and how these roles might be tested in the avian model.

  20. FGF9, activin and TGFβ promote testicular characteristics in an XX gonad organ culture model.

    PubMed

    Gustin, Sonja E; Stringer, Jessica M; Hogg, Kirsten; Sinclair, Andrew H; Western, Patrick S

    2016-11-01

    Testis development is dependent on the key sex-determining factors SRY and SOX9, which activate the essential ligand FGF9. Although FGF9 plays a central role in testis development, it is unable to induce testis formation on its own. However, other growth factors, including activins and TGFβs, also present testis during testis formation. In this study, we investigated the potential of FGF9 combined with activin and TGFβ to induce testis development in cultured XX gonads. Our data demonstrated differing individual and combined abilities of FGF9, activin and TGFβ to promote supporting cell proliferation, Sertoli cell development and male germ line differentiation in cultured XX gonads. FGF9 promoted proliferation of supporting cells in XX foetal gonads at rates similar to those observed in vivo during testis cord formation in XY gonads but was insufficient to initiate testis development. However, when FGF9, activin and TGFβ were combined, aspects of testicular development were induced, including the expression of Sox9, morphological reorganisation of the gonad and deposition of laminin around germ cells. Enhancing β-catenin activity diminished the testis-promoting activities of the combined growth factors. The male promoting activity of FGF9 and the combined growth factors directly or indirectly extended to the germ line, in which a mixed phenotype was observed. FGF9 and the combined growth factors promoted male germ line development, including mitotic arrest, but expression of pluripotency genes was maintained, rather than being repressed. Together, our data provide evidence that combined signalling by FGF9, activin and TGFβ can induce testicular characteristics in XX gonads.

  1. Determination of gonad doses during robotic stereotactic radiosurgery for various tumor sites

    SciTech Connect

    Zorlu, Faruk; Dugel, Gozde; Ozyigit, Gokhan; Hurmuz, Pervin; Cengiz, Mustafa; Yildiz, Ferah; Akyol, Fadil; Gurkaynak, Murat

    2013-04-15

    Purpose: The authors evaluated the absorbed dose received by the gonads during robotic stereotactic radiosurgery (SRS) for the treatment of different tumor localizations. Methods: The authors measured the gonad doses during the treatment of head and neck, thoracic, abdominal, or pelvic tumors in both RANDO phantom and actual patients. The computerized tomography images were transferred to the treatment planning system. The contours of tumor and critical organs were delineated on each slice, and treatment plans were generated. Measurements for gonad doses were taken from the geometric projection of the ovary onto the skin for female patients, and from the scrotal skin for male patients by attaching films and Thermoluminescent dosimeters (TLDs). SRS was delivered with CyberKnife (Accuray Inc., Sunnyvale, CA). Results: The median gonadal doses with TLD and film dosimeter in actual patients were 0.19 Gy (range, 0.035-2.71 Gy) and 0.34 Gy (range, 0.066-3.18 Gy), respectively. In the RANDO phantom, the median ovarian doses with TLD and film dosimeter were 0.08 Gy (range, 0.03-0.159 Gy) and 0.05 Gy (range, 0.015-0.13 Gy), respectively. In the RANDO phantom, the median testicular doses with TLD and film dosimeter were 0.134 Gy (range 0.056-1.97 Gy) and 0.306 Gy (range, 0.065-2.25 Gy). Conclusions: Gonad doses are below sterility threshold in robotic SRS for different tumor localizations. However, particular attention should be given to gonads during robotic SRS for pelvic tumors.

  2. Gonadal hormone-dependent and -independent regulation of immune function by photoperiod in Siberian hamsters.

    PubMed

    Prendergast, Brian J; Baillie, Scott R; Dhabhar, Firdaus S

    2008-02-01

    Siberian hamsters (Phodopus sungorus) exhibit changes in reproductive and immune function in response to seasonal variations in day length. Exposure to short days induces gonadal regression and inhibits testosterone secretion. In parallel, short days enhance immune function: increasing leukocyte numbers and attenuating cytokine and behavioral responses to infection. We examined whether photoperiodic changes in leukocyte phenotypes and sickness behaviors are dependent on concurrent photoperiodic changes in gonadal function. Male hamsters were gonadectomized or sham-gonadectomized and either exposed to short days (9 h light/day; SD) or kept in their natal long-day (15 h light/day; LD) photoperiod for 10-13 wk. Blood samples were obtained for leukocyte enumeration, and hamsters were challenged with bacterial LPS, which induced behavioral (anorexia, reductions in nest building) and somatic (weight loss) sickness responses. Among gonad-intact hamsters, exposure to SD increased total and CD62L+ lymphocytes and CD3+ T lymphocytes in blood and significantly attenuated LPS-induced sickness responses. Independent of photoperiod, castration alone increased total and CD62L+ lymphocyte and CD3+ T lymphocyte numbers and attenuated somatic and anorexic sickness responses. Among castrated hamsters, SD exposure increased lymphocyte numbers and suppressed sickness behaviors. In castrated hamsters, the magnitude of most immunological effects of SD were diminished relative to those evident in gonad-intact hamsters. The SD phenotype in several measures of immunity can be instated via elimination of gonadal hormones alone; however, photoperiodic effects on immune function persist even in castrated hamsters. Thus, photoperiod affects the immune system and neural-immune interactions underlying sickness behaviors via gonadal hormone-dependent and -independent mechanisms.

  3. FGF9, activin and TGFβ promote testicular characteristics in an XX gonad organ culture model.

    PubMed

    Gustin, Sonja E; Stringer, Jessica M; Hogg, Kirsten; Sinclair, Andrew H; Western, Patrick S

    2016-11-01

    Testis development is dependent on the key sex-determining factors SRY and SOX9, which activate the essential ligand FGF9. Although FGF9 plays a central role in testis development, it is unable to induce testis formation on its own. However, other growth factors, including activins and TGFβs, also present testis during testis formation. In this study, we investigated the potential of FGF9 combined with activin and TGFβ to induce testis development in cultured XX gonads. Our data demonstrated differing individual and combined abilities of FGF9, activin and TGFβ to promote supporting cell proliferation, Sertoli cell development and male germ line differentiation in cultured XX gonads. FGF9 promoted proliferation of supporting cells in XX foetal gonads at rates similar to those observed in vivo during testis cord formation in XY gonads but was insufficient to initiate testis development. However, when FGF9, activin and TGFβ were combined, aspects of testicular development were induced, including the expression of Sox9, morphological reorganisation of the gonad and deposition of laminin around germ cells. Enhancing β-catenin activity diminished the testis-promoting activities of the combined growth factors. The male promoting activity of FGF9 and the combined growth factors directly or indirectly extended to the germ line, in which a mixed phenotype was observed. FGF9 and the combined growth factors promoted male germ line development, including mitotic arrest, but expression of pluripotency genes was maintained, rather than being repressed. Together, our data provide evidence that combined signalling by FGF9, activin and TGFβ can induce testicular characteristics in XX gonads. PMID:27495231

  4. Gonadal sex differentiation in frogs: how testes become shorter than ovaries.

    PubMed

    Haczkiewicz, Katarzyna; Ogielska, Maria

    2013-02-01

    Testis differentiation in anuran amphibians is the result of two opposing processes: degeneration of the distal part, and development of the proximal part, which becomes a functional male gonad. Undifferentiated gonad differentiates directly into a testis without a transition phase. We described the morphology of developing testes in Rana temporaria and Hyla arborea, and made careful histology and ultrastructure in Pelophylax lessonae. The developing testis was divided into 10 stages (I-III, undifferentiated gonad, IV-X, testis). The earliest morphological symptoms of testis differentiation were observed in 4- to 5-week-old tadpoles at Gosner stage 27-28. At that time an undifferentiated gonad, composed of 6-9 metameres, differentiates into a testis. The proximal metameres (2-3 in the right gonad and 3-4 in the left one) differentiate into a functional testis, while the distal ones degenerate. The difference between left and right gonad size is maintained until adulthood (stage X). Degeneration of the distal part progresses along the posterior-anterior gradient and starts at stage IV. It affects first the germ cells with accompanying precursor Sertoli cells, and then the mesenchymal cells and fibroblasts. Finally the external epithelium forms a "sleeve" around the almost empty distal part. The total length of the testes stays the same until stage VIII at Gosner stage 41 (age 74-148 days). Active spermatogenesis starts at stage IX (juveniles after their first hibernation), during which the distal part eventually disappears and the proximal part starts growing considerably due to progressing spermatogenesis.

  5. Marked reduction in gonadal steroid hormone levels in rats treated neonatally with monosodium L-glutamate: further evidence for disruption of hypothalamic-pituitary-gonadal axis regulation.

    PubMed

    Nemeroff, C B; Lamartiniere, C A; Mason, G A; Squibb, R E; Hong, J S; Bondy, S C

    1981-11-01

    Serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, estradiol-17 beta and testosterone were determined in adult rats that were treated in the neonatal period with monosodium L-glutamate (MSG) which has previously been shown to reliably produce destruction of arcuate nucleus perikarya. MSG-treated males had significantly smaller accessory sexual organs (seminal vesicles and ventral prostate) and tests and had significantly lower serum concentrations of FSH and testosterone than sex-matched controls. MSG-treated females had significantly lower serum concentrations of LH, FSH and estradiol-17 beta. Prolactin levels of MSG-treated rats were no different than sex-matched controls. This marked reduction in gonadal steroid levels (decreases 68%) and inappropriately low gonadotropin levels further characterizes the deficit of feedback regulation in the hypothalamic-pituitary-gonadal axis in MSG-treated rats.

  6. Immunohistochemical evidence that gonads and gonad-associated tissues are sites for enrichment with immunoglobulin-containing cells in adult chickens.

    PubMed

    Zettergren, L D

    1995-01-01

    Immunohistochemical staining of tissue sections prepared from gonads and gonad-associated tissues obtained from adult chickens was performed in order to assess the possibility that these tissues may be sites of enrichment with IgM-containing cells in various B lineages. Evidence is presented which suggests that IgM-containing B lineage cells are present in 1) the ovarian stroma and subcapsular areas of the ovary and 2) the interstitium and subcapsular areas of the epididymis of the testes. These represent new sites reported for B lineage cells in adult chickens. Some questions relevant to the physiologic, ontogenetic, and phylogenetic implications of these observations relative to vertebrate hematolymphopoietic processes are included.

  7. Motoneuron injury and repair: New perspectives on gonadal steroids as neurotherapeutics.

    PubMed

    Tetzlaff, Julie E; Huppenbauer, Christopher B; Tanzer, Lisa; Alexander, Thomas D; Jones, Kathryn J

    2006-01-01

    In this review, we will summarize recent work from our laboratory on the role of gonadal steroids as neuroprotective agents in motoneuron viability following cell stress. Three motoneuron models will be discussed: developing axotomized hamster facial motoneurons (FMNs); adult axotomized mouse FMNs; and immortalized, cultured mouse spinal motoneurons subjected to heat shock. New work on two relevant motoneuron proteins, the survival of motor neuron protein, and neuritin or candidate plasticity-related gene 15, indicates differential steroid regulation of these two proteins after axotomy. The concept of gonadal steroids as cellular stress correction factors and the implications of this for acute neurological injury situations will be presented as well. PMID:16632875

  8. Impotence is not always psychogenic. Newer insights into hypothalamic-pituitary-gonadal dysfunction.

    PubMed

    Spark, R F; White, R A; Connolly, P B

    The concept that impotence is psychogenic in 95% of cases is reconsidered. Screening serum testosterone levels of 105 consecutive patients with impotence showed that 37 patients had previously unsuspected disorders of the hypothalamic-pituitary-gonadal axis. Twenty patients had hypogonadotropic-hypogonadism, seven had hypergonadotropic-hypogonadism, eight had hyperprolactinemia, and two had occult hyperthyroidism. Once the specific defect was defined, appropriate therapy was instituted, and potency was restored in 33 patients. Screening serum testosterone levels is useful in identifying hypothalamic-pituitary-gonadal dysfunction in patients with impotence.

  9. The aging male hypothalamic-pituitary-gonadal axis: pulsatility and feedback.

    PubMed

    Veldhuis, Johannes D; Keenan, Daniel M; Liu, Peter Y; Iranmanesh, Ali; Takahashi, Paul Y; Nehra, Ajay X

    2009-02-01

    Aging results in insidious decremental changes in hypothalamic, pituitary and gonadal function. The foregoing three main anatomic loci of control are regulated by intermittent time-delayed signal exchange, principally via gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and testosterone/estradiol (Te/E(2)). A mathematical framework is required to embody these dynamics. The present review highlights integrative adaptations in the aging male hypothalamic-pituitary-gonadal axis, as assessed by recent objective ensemble models of the axis as a whole.

  10. Is there hypothalamic-pituitary-gonadal dysfunction in paedophilia? A pilot study.

    PubMed

    Gaffney, G R; Berlin, F S

    1984-12-01

    The hypothalamic - pituitary - gonadal axis was evaluated in men with paedophilia and non-paedophilic paraphilia, and in normal male controls, by infusion of 100 mcg. of synthetic luteinising hormone-releasing hormone (LHRH). There were no significant differences among groups in age, height, weight, testosterone, baseline luteinising hormone (LH) and follicle stimulating hormone (FSH), and FSH response to LHRH. However, there was a significant difference between the paedophilic group and the other two groups in the LH response to LHRH. The paedophiles responded with a marked elevation of LH, when compared with the non-paedophilic paraphiliacs and controls. These data indicate a hypothalamic - pituitary - gonadal dysfunction in paedophiles.

  11. The Aging Male Hypothalamic-Pituitary-Gonadal Axis: pulsatility and feedback

    PubMed Central

    Veldhuis, Johannes D.; Keenan, Daniel M.; Liu, Peter Y.; Iranmanesh, Ali; Takahashi, Paul Y.; Nehra, Ajay X.

    2009-01-01

    Aging results in insidious decremental changes in hypothalamic, pituitary and gonadal function. The foregoing three main anatomic loci of control are regulated by intermittent time-delayed signal exchange, principally via gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and testosterone/estradiol (Te/E2). A mathematical framework is required to embody these dynamics. The present review highlights integrative adaptations in the aging male hypothalamic-pituitary-gonadal axis, as assessed by recent objective ensemble models of the axis as a whole. PMID:18838102

  12. Two gonad-infecting species of Philometra (Nematoda: Philometridae) from groupers (Serranidae) off Tunisia, with a key to Philometra species infecting serranid gonads.

    PubMed

    Moravec, František; Chaabane, Amira; Justine, Jean-Lou; Neifar, Lassad

    2016-01-01

    Based on light and scanning electron microscopical studies of nematode specimens (males and mature females) collected from the ovary of groupers (Serranidae, Perciformes) in the Mediterranean Sea off Tunisia (near Tunis and Sfax), two gonad-infecting species of Philometra Costa, 1845 (Nematoda, Philometridae) are reported: Philometra inexpectata n. sp. from the mottled grouper Mycteroperca rubra and P. jordanoi (López-Neyra, 1951) from the dusky grouper Epinephelus marginatus. Identification of both fish species was confirmed by molecular barcoding. The new species is mainly characterized by the length of equally long spicules (147-165 μm), the gubernaculum (63-93 μm long) bearing at the tip two dorsolateral lamellar parts separated from each other by a smooth median field, a V-shaped mound on the male caudal extremity, the presence of a pair of large caudal papillae located posterior to the cloaca and by the body length of the males (1.97-2.43 mm). Philometra inexpectata n. sp. is the fifth known gonad-infecting philometrid species parasitizing serranid fishes in the Mediterranean region. The males of P. jordanoi were examined by scanning electron microscopy for the first time; this detailed study revealed some new taxonomically important morphological features, such as the number and arrangement of cephalic and caudal papillae, presence of amphids and phasmids and mainly the lamellate structures at the posterior end of the gubernaculum. A key to gonad-infecting species of Philometra parasitic in serranid fishes is provided. PMID:26956219

  13. Two gonad-infecting species of Philometra (Nematoda: Philometridae) from groupers (Serranidae) off Tunisia, with a key to Philometra species infecting serranid gonads.

    PubMed

    Moravec, František; Chaabane, Amira; Justine, Jean-Lou; Neifar, Lassad

    2016-01-01

    Based on light and scanning electron microscopical studies of nematode specimens (males and mature females) collected from the ovary of groupers (Serranidae, Perciformes) in the Mediterranean Sea off Tunisia (near Tunis and Sfax), two gonad-infecting species of Philometra Costa, 1845 (Nematoda, Philometridae) are reported: Philometra inexpectata n. sp. from the mottled grouper Mycteroperca rubra and P. jordanoi (López-Neyra, 1951) from the dusky grouper Epinephelus marginatus. Identification of both fish species was confirmed by molecular barcoding. The new species is mainly characterized by the length of equally long spicules (147-165 μm), the gubernaculum (63-93 μm long) bearing at the tip two dorsolateral lamellar parts separated from each other by a smooth median field, a V-shaped mound on the male caudal extremity, the presence of a pair of large caudal papillae located posterior to the cloaca and by the body length of the males (1.97-2.43 mm). Philometra inexpectata n. sp. is the fifth known gonad-infecting philometrid species parasitizing serranid fishes in the Mediterranean region. The males of P. jordanoi were examined by scanning electron microscopy for the first time; this detailed study revealed some new taxonomically important morphological features, such as the number and arrangement of cephalic and caudal papillae, presence of amphids and phasmids and mainly the lamellate structures at the posterior end of the gubernaculum. A key to gonad-infecting species of Philometra parasitic in serranid fishes is provided.

  14. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  15. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  16. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  17. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  18. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  19. Karyological and gonadal sex of eels (Anguilla anguilla) from the German Bight and the lower River Elbe

    NASA Astrophysics Data System (ADS)

    Passakas, T.; Tesch, F.-W.

    1980-06-01

    Yellow eels (Anguilla anguilla) taken during summer from random commercial trapnet samples in the littoral area of Helgoland (n=116) and from a freshwater area of the River Elbe near Hamburg (n=109) were examined with regard to their karyological (i.e. existence of female sex chromosomes) and gonadal sex. In 47 % and 21 % of the two samples, respectively, chromosomes were unidentifiable because of insufficient numbers of mitotic plates. All eels from Helgoland, except one phenotypically undetermined fish, exhibited female gonads: 48 had female sex chromosomes and 13 were karyologically males. As found previously in the River Elbe, eels with male gonads predominated (n=55); 25 were undifferentiated. Of the gonadal males 26 were karyological males and 16 karyological females; the rest could not be identified by chromosome patterns. In contrast, all but one of the Elbe eels with female gonads (n=28) had female sex chromosomes. Some aspects of the sex reversal documented in the eel are considered.

  20. Effects of the isoflavones genistein and equol on the gonadal development of Japanese medaka Oryzias latipes.

    PubMed Central

    Kiparissis, Yiannis; Balch, Gordon C; Metcalfe, Tracy L; Metcalfe, Chris D

    2003-01-01

    The estrogenic isoflavone compound genistein recently has been found in the effluents of sewage treatment plants and pulp mills, and the related compound equol has been detected in the runoff from agricultural fields treated with hog manure. Waterborne exposures of Japanese medaka (Oryzias latipes) to equol from soon after hatch to approximately 100 days posthatch induced gonadal intersex (i.e., testis-ova) in males at incidences of 10 and 87% in equol treatments of 0.4 and 0.8 micro g/L, respectively. Exposure to the highest test concentration of genistein, 1,000 micro g/L, also caused a low incidence (i.e., 12%) of gonadal intersex in male medaka. The ovaries of female medaka from both equol and genistein treatments showed delayed oocyte maturation, atretic oocytes, an enlarged ovarian lumen, proliferation of somatic stromal tissue, and primordial germ cells; responses were concentration dependent. Alterations to externally visible secondary sex characteristics occurred in medaka exposed to both equol and genistein. In treatments with 1,000 micro g/L genistein, 72% of male medaka (as identified by the gonadal phenotype) showed feminized secondary sex characteristics. Gonadal intersex and alterations to secondary sex characteristics have been noted in several fish populations around the world. This laboratory study indicates that isoflavone compounds should be considered candidate estrogenic compounds that may be involved in the alteration of sexual development in feral fish populations. PMID:12842767

  1. Adaptive Responses to Prochloraz Exposure in the Hypothalamic-Pituitary Gonadal Axis of Fathead Minnows

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict doseresponse and time-course ...

  2. Experiment K-7-19: Pineal Physiology After Spaceflight: Relation to Rat Gonadal Function

    NASA Technical Reports Server (NTRS)

    Holley, D. C.; Soliman, M. R. I.; Krasnov, I.; Asadi, H.

    1994-01-01

    The function of pineal exposed to microgravity and spaceflight is studied. It is found that the spaceflight resulted in a stress response as indicated by adrenal hypertrophy, that gonadal function was compromised, and that the pineal may be linked as part of the mechanisms of the response noted.

  3. Opposite influence of light and blindness on pituitary-gonadal function.

    PubMed

    Bellastella, Antonio; De Bellis, Annamaria; Bellastella, Giuseppe; Esposito, Katherine

    2014-01-13

    Some environmental factors may influence the pituitary-gonadal function. Among these, light plays an important role in animals and in humans. The effect of light on the endocrine system is mediated by the pineal gland, through the modulation of melatonin secretion. In fact, melatonin secretion is stimulated by darkness and suppressed by light, thus its circadian rhythm peaks at night. Light plays a favorable action on the hypothalamic-pituitary axis likely inhibiting melatonin secretion, while the exogenous melatonin administration does not seem to impair the hormonal secretions of this axis. The basal and rhythmic pituitary-gonadal hormone secretions are regulated by a central clock gene and some independent clock genes in the peripheral tissues. Light is able to induce the expression of some of these genes, thus playing an important role in regulating the hormonal secretions of pituitary-gonadal axis and the sexual and reproductive function in animals and humans. The lack of light stimulus in blind subjects induces increase in plasma melatonin concentrations with a free-running rhythm of secretion, which impairs the hormonal secretions of pituitary-gonadal axis, causing disorders of reproductive processes in both sexes.

  4. Gonadal (ovarian) dysgenesis in 46,XX individuals: Frequency of the autosomal recessive form

    SciTech Connect

    Meyers, C.M.; Boughman, J.A.; Rivas, M.

    1996-06-28

    Gonadal (ovarian) dysgenesis with normal chromosomes (46,XX) clearly is a heterogeneous condition. In some forms, the defect is restricted to the gonads, whereas other affected females show neurosensory hearing loss (Perrault syndrome). In another form, brothers may have germ cell aplasia. Nongenetic causes exist as well. To elucidate the proportion of XX gonadal (ovarian) dysgenesis due to autosomal recessive genes, we analyzed published (N = 17) and unpublished (N = 8) families having at least two female offspring. Analysis was restricted to cases in whom ovarian failure was documented by the presence of streak ovaries (published cases) or elevated gonadotropins (unpublished cases). We reasoned that the closer to that segregation ratio expected for an autosomal recessive trait (0.25), the lower the frequency of nongenetic forms. Segregation analysis utilized standard correction for single ascertainment, with only females included in the preliminary analysis. The segregation ratio estimate was 0.16. Our results suggest that many 46,XX females with gonadal (ovarian) dysgenesis represent a disorder segregating as an autosomal recessive trait, placing sisters of these cases at a 25% risk for this disorder. 32 refs., 2 figs., 1 tab.

  5. Longitudinal gonadal steroid excretion in free-living male and female meerkats (Suricata suricatta).

    PubMed

    Moss, A M; Clutton-Brock, T H; Monfort, S L

    2001-05-01

    Slender-tailed meerkats (Suricata suricatta) are small, diurnal, cooperatively breeding mongooses of the family Herpestidae. A prerequisite to fully understanding the mating system of meerkats is the development of a normative reproductive-endocrine database. This study examined longitudinal gonadal steroid excretion in all adult and juvenile individuals of both sexes within a social group of free-living meerkats sampled across an entire breeding season. The specific objectives of this study were to (1) validate noninvasive (fecal and urinary) gonadal steroid hormone monitoring techniques in male (testosterone) and female (estrogens, progestagens) meerkats; (2) test the feasibility of using these noninvasive methods under field conditions; (3) characterize the endocrine correlates associated with the female reproductive cycle, including estrus, gestation, and postpartum estrus; (4) examine longitudinal androgen excretion in males; and (5) determine whether social status (i.e., dominant versus subordinate) affected gonadal steroid excretion. In females, the results demonstrated the physiological validity of noninvasive monitoring in meerkats by corresponding excretory hormone concentrations to major reproductive events (i.e., estrous, pregnancy, parturition). Hormone excretory patterns during estrous intervals suggested possible mechanisms whereby reproductive suppression may operate in female meerkats. In males, androgen excretion did not correspond to changes in reproductive and aggressive behaviors, suggesting that dominance, and hence breeding access to females, was not regulated strictly by gonadal steroid production. The consistency in androgen excretion among male meerkats indicated that reproductive suppression may be mediated by behavioral (i.e., intermale aggression) rather than physiological (i.e., depressed spermatogenesis) mechanisms.

  6. Global DNA methylation in gonads of adult zebrafish Danio rerio under bisphenol A exposure.

    PubMed

    Liu, Yan; Zhang, Yingying; Tao, Shiyu; Guan, Yongjing; Zhang, Ting; Wang, Zaizhao

    2016-08-01

    Altered DNA methylation is pervasively associated with changes in gene expression and signal transduction after exposure to a wide range of endocrine disrupting chemicals. As a weak estrogenic chemical, bisphenol A (BPA) has been extensively studied for reproductive toxicity. In order to explore the effects of BPA on epigenetic modification in gonads of zebrafish Danio rerio, we measured the global DNA methylation together with the gene expression of DNA methyltransferase (dnmts), glycine N-methyltransferase (gnmt), and ten-eleven translocation (tets) in gonads of D. rerio under BPA exposure by ELISA and quantitative real-time PCR method, respectively. The global level of DNA methylation was significantly decreased in ovaries after exposed to BPA for 7 days, and testes following 35-day exposure. Moreover, the global level of DNA methylation was also significantly reduced in testes after exposed to 15μg/L BPA for 7 days. Besides the alteration of the global level of DNA methylation, varying degrees of transcriptional changes of dnmts, gnmt and tets were detected in gonads of D. rerio under BPA exposure. The present study suggested that BPA might cause the global DNA demethylation in gonads of zebrafish by regulating the transcriptional changes of the DNA methylation/demethylation-associated genes (dnmts, gnmt, and tets). PMID:27101439

  7. Reproductive cycle and gonad development of the Northern Argentinean Mesodesma mactroides (Bivalvia: Mesodesmatidae)

    NASA Astrophysics Data System (ADS)

    Herrmann, Marko; Alfaya, José E. F.; Lepore, Mauro L.; Penchaszadeh, Pablo E.; Laudien, Jürgen

    2009-09-01

    The reproductive cycle and gonad development of the yellow clam Mesodesma mactroides was studied over a period of 24 months (January 2005-December 2006) at the Argentinean sandy beach Santa Teresita. Histological examination of gonadal tissue revealed that sex ratios did not significantly deviate from the proportion of 1:1 and no case of hermaphroditism was found. The reproductive cycle of M. mactroides followed an annual cyclicality, which was significantly correlated to monthly mean sea surface temperatures (SST). Oocytes showed highest abundance in winter, indicating a process of gonadal development and sexual maturation. The mean oocyte size decreased significantly during spring. Modal oocyte sizes decreased significantly during winter and late spring of each year, suggesting spawning events. The condition index was not useful in describing the annual reproductive cycle of M. mactroides. Ash-free, shell-free dry mass was chosen to detect the condition of the specimens, and this significantly correlated with monthly mean SST and the gametogenic cycle. Annual recruitment patterns during summer-autumn indicated a 3-month-long planktonic phase of M. mactroides. The reproduction cycle and gonad development of M. mactroides showed only weak differences between data from the present study and those collected 40 years ago.

  8. Sex differences in ischemic stroke sensitivity are influenced by gonadal hormones, not by sex chromosome complement.

    PubMed

    Manwani, Bharti; Bentivegna, Kathryn; Benashski, Sharon E; Venna, Venugopal Reddy; Xu, Yan; Arnold, Arthur P; McCullough, Louise D

    2015-02-01

    Epidemiologic studies have shown sex differences in ischemic stroke. The four core genotype (FCG) mouse model, in which the testes determining gene, Sry, has been moved from Y chromosome to an autosome, was used to dissociate the effects of sex hormones from sex chromosome in ischemic stroke outcome. Middle cerebral artery occlusion (MCAO) in gonad intact FCG mice revealed that gonadal males (XXM and XYM) had significantly higher infarct volumes as compared with gonadal females (XXF and XYF). Serum testosterone levels were equivalent in adult XXM and XYM, as was serum estrogen in XXF and XYF mice. To remove the effects of gonadal hormones, gonadectomized FCG mice were subjected to MCAO. Gonadectomy significantly increased infarct volumes in females, while no change was seen in gonadectomized males, indicating that estrogen loss increases ischemic sensitivity. Estradiol supplementation in gonadectomized FCG mice rescued this phenotype. Interestingly, FCG male mice were less sensitive to effects of hormones. This may be due to enhanced expression of the transgene Sry in brains of FCG male mice. Sex differences in ischemic stroke sensitivity appear to be shaped by organizational and activational effects of sex hormones, rather than sex chromosomal complement.

  9. Intersex gonads in frogs: understanding the time course of natural development and role of endocrine disruptors.

    PubMed

    Storrs-Méndez, Sara I; Semlitsch, Raymond D

    2010-01-15

    The paucity of data on sexual development of anuran amphibians has played an important role in the recent controversy over atrazine exposure. Although some studies have demonstrated the presence of abnormal gonads in control treatments, others have not, leading to varying interpretations of the effects of atrazine exposure on sexual development. However, the timing of development varies among anuran amphibians such that, at any snapshot in time, different species may exhibit different stages of sexual differentiation. We examined three species representing each of the differentiation rates (Bufo americanus=retarded rate; Hyla versicolor=basic rate; Rana sphenocephala=accelerated rate), to examine the natural time course of sexual development along with the influence of atrazine exposure. For each species, exposure to atrazine (1, 3, 10, 30 parts per billion), 17-beta-estradiol or control water occurred throughout larval life. Gonad histology was performed at 3-week intervals during the larval period or at a juvenile stage to examine the proportion of males, females, underdeveloped testes, testicular oocytes (TO; testes with 0-30% oocytes), and ovotestes (OVTs; testes with>30% oocytes). Our results illustrate that a phase of intersex gonads (TO or OVT) is normal during R. sphenocephala sexual development, a species representing the accelerated differentiation rate. Further, intersex gonads were found in juvenile stages of B. americanus and H. versicolor, representing retarded and basic rates, respectively, suggesting that a phase of intersex may be common regardless of differentiation rate. Moreover, these data highlight the importance of longitudinal studies rather than snapshots in time.

  10. The Drosophila Actin Regulator ENABLED Regulates Cell Shape and Orientation during Gonad Morphogenesis

    PubMed Central

    Sano, Hiroko; Barbosa, Vitor; Clark, Ivan B. N.; Ishihara, Shuji; Sugimura, Kaoru; Lehmann, Ruth

    2012-01-01

    Organs develop distinctive morphologies to fulfill their unique functions. We used Drosophila embryonic gonads as a model to study how two different cell lineages, primordial germ cells (PGCs) and somatic gonadal precursors (SGPs), combine to form one organ. We developed a membrane GFP marker to image SGP behaviors live. These studies show that a combination of SGP cell shape changes and inward movement of anterior and posterior SGPs leads to the compaction of the spherical gonad. This process is disrupted in mutants of the actin regulator, enabled (ena). We show that Ena coordinates these cell shape changes and the inward movement of the SGPs, and Ena affects the intracellular localization of DE-cadherin (DE-cad). Mathematical simulation based on these observations suggests that changes in DE-cad localization can generate the forces needed to compact an elongated structure into a sphere. We propose that Ena regulates force balance in the SGPs by sequestering DE-cad, leading to the morphogenetic movement required for gonad compaction. PMID:23300733

  11. Biogenic acidification reduces sea urchin gonad growth and increases susceptibility of aquaculture to ocean acidification.

    PubMed

    Mos, Benjamin; Byrne, Maria; Dworjanyn, Symon A

    2016-02-01

    Decreasing oceanic pH (ocean acidification) has emphasised the influence of carbonate chemistry on growth of calcifying marine organisms. However, calcifiers can also change carbonate chemistry of surrounding seawater through respiration and calcification, a potential limitation for aquaculture. This study examined how seawater exchange rate and stocking density of the sea urchin Tripneustes gratilla that were reproductively mature affected carbonate system parameters of their culture water, which in turn influenced growth, gonad production and gonad condition. Growth, relative spine length, gonad production and consumption rates were reduced by up to 67% by increased density (9-43 individuals.m(-2)) and reduced exchange rates (3.0-0.3 exchanges.hr(-1)), but survival and food conversion efficiency were unaffected. Analysis of the influence of seawater parameters indicated that reduced pH and calcite saturation state (ΩCa) were the primary factors limiting gonad production and growth. Uptake of bicarbonate and release of respiratory CO2 by T. gratilla changed the carbonate chemistry of surrounding water. Importantly total alkalinity (AT) was reduced, likely due to calcification by the urchins. Low AT limits the capacity of culture water to buffer against acidification. Direct management to counter biogenic acidification will be required to maintain productivity and reproductive output of marine calcifiers, especially as the ocean carbonate system is altered by climate driven ocean acidification.

  12. Direct effects of triiodothyronine on production of anterior pituitary hormones and gonadal steroids in goldfish.

    PubMed

    Allan, Euan R O; Habibi, Hamid R

    2012-09-01

    The present study investigated the effects of triiodothyronine (T3) on pituitary gonadotropin (GTH) subunits, thyroid stimulating hormone (TSH) β subunit, and growth hormone (GH) mRNA levels, as well as gonadal steroid secretion during different stages of reproduction in goldfish. Goldfish pituitary cells cultured with T3 exhibited lower tshβ mRNA levels in all reproductive stages and lower luteinising hormone β (lhβ) mRNA levels in early recrudescence, whereas gh and fshβ mRNA levels were not altered. T3 injections significantly reduced circulating oestrogen (OE2) concentrations in early and mid recrudescent male goldfish, but were without effect on the circulating level of OE2 in female fish. T3 injections also reduced circulating levels of testosterone in both male and female goldfish during the mid stage of gonadal recrudescence. In vitro culture of goldfish ovarian follicles at the late stage of gonadal recrudescence, in the presence of T3, resulted in reduced OE2 secretion; no consistent effect of T3 on testosterone secretion was observed in cultured goldfish ovarian follicles and testis. These findings support the hypothesis that T3 impairs reproduction by inhibiting production of gonadal steroids and pituitary luteinising hormone production in goldfish.

  13. Postnatal breast development of preterm infants. An index of gonadal function.

    PubMed Central

    McKiernan, J

    1984-01-01

    Development of breast nodules after birth was examined in 17 preterm infants; nodules developed regularly in girls but not boys. It is concluded that the pituitary-gonadal axis of preterm infants is active in the months after birth and that in preterm infants there is a definite phase of breast growth in early postnatal life. PMID:6508344

  14. Adaptive Response in Female Modeling of the Hypothalamic-pituitary-gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course ...

  15. Longitudinal gonadal steroid excretion in free-living male and female meerkats (Suricata suricatta).

    PubMed

    Moss, A M; Clutton-Brock, T H; Monfort, S L

    2001-05-01

    Slender-tailed meerkats (Suricata suricatta) are small, diurnal, cooperatively breeding mongooses of the family Herpestidae. A prerequisite to fully understanding the mating system of meerkats is the development of a normative reproductive-endocrine database. This study examined longitudinal gonadal steroid excretion in all adult and juvenile individuals of both sexes within a social group of free-living meerkats sampled across an entire breeding season. The specific objectives of this study were to (1) validate noninvasive (fecal and urinary) gonadal steroid hormone monitoring techniques in male (testosterone) and female (estrogens, progestagens) meerkats; (2) test the feasibility of using these noninvasive methods under field conditions; (3) characterize the endocrine correlates associated with the female reproductive cycle, including estrus, gestation, and postpartum estrus; (4) examine longitudinal androgen excretion in males; and (5) determine whether social status (i.e., dominant versus subordinate) affected gonadal steroid excretion. In females, the results demonstrated the physiological validity of noninvasive monitoring in meerkats by corresponding excretory hormone concentrations to major reproductive events (i.e., estrous, pregnancy, parturition). Hormone excretory patterns during estrous intervals suggested possible mechanisms whereby reproductive suppression may operate in female meerkats. In males, androgen excretion did not correspond to changes in reproductive and aggressive behaviors, suggesting that dominance, and hence breeding access to females, was not regulated strictly by gonadal steroid production. The consistency in androgen excretion among male meerkats indicated that reproductive suppression may be mediated by behavioral (i.e., intermale aggression) rather than physiological (i.e., depressed spermatogenesis) mechanisms. PMID:11316421

  16. Effects of Chinese domestic polychlorinated biphenyls (PCBs) on gonadal differentiation in Xenopus laevis.

    PubMed Central

    Qin, Zhan-Fen; Zhou, Jing-Ming; Chu, Shao-Gang; Xu, Xiao-Bai

    2003-01-01

    To determine whether polychlorinated biphenyls (PCBs) influence gonadal differentiation in Xenopus laevis, tadpoles were exposed to two Chinese domestic PCBs (PCB3 and PCB5 from Nieuwkoop and Faber stage 46/47 to complete metamorphosis. Gonads were characterized using a dissecting microscope. The control X. laevis had normal ovaries or testes in gross morphology, whereas obviously abnormal testes including ovotestes were found in PCB3- and PCB5-exposed groups. Ovotestes were characterized by morphologic ovaries in the cranial and caudal parts and morphologic testes in the middle part. PCBs did not alter the percentage of females but reduced the percentage of males with morphologically normal testes. The histologic structure of gonads was examined by a series of sections. Morphologically normal and abnormal testes from a few frogs exposed to PCBs were interspersed with oocytes in histologic sections. These testes exhibited looser structure with fewer seminiferous tubes, spermatogonia, and spermatozoa than in controls. The findings suggest that PCB3 and PCB5 have significant feminization effects on gonadal differentiation in X. laevis and that this species is sensitive to endocrine disruption and may be used as a good model to study endocrine disruption. PMID:12676614

  17. Leptin Genes in Blunt Snout Bream: Cloning, Phylogeny and Expression Correlated to Gonads Development

    PubMed Central

    Zhao, Honghao; Zeng, Cong; Yi, Shaokui; Wan, Shiming; Chen, Boxiang; Gao, Zexia

    2015-01-01

    To investigate the leptin related genes expression patterns and their possible function during the gonadal development in fish, the cDNA and genomic sequences of leptin, leptin receptor (leptinR), and leptin receptor overlapping transcript like-1 (leprotl1) were cloned and their expression levels were quantified in the different gonadal development stages of Megalobrama amblycephala. The results showed that the full length cDNA sequences of leptin, leptinR and leprotl1 were 953, 3432 and 1676 bp, coding 168, 1082, and 131 amino acid polypeptides, and the genomic sequences were 1836, 28,528 and 5480 bp, which respectively had 3, 15 and 4 exons, respectively. The phylogenetic analysis revealed that three genes were relatively conserved in fish species. Quantitative real-time PCR results showed that the three genes were ubiquitously expressed in all examined tissues during the different gonadal development stages. The leptin and leptinR took part in the onset of puberty, especially in female M. amblycephala, by increasing the expression levels in brain during the stage I to III of ovary. The expression levels of leptin and leptinR had significant differences between male and female in hypothalamic-pituitary-gonadal (HPG) axis tissues (p < 0.05). The leptinR had the same variation tendency with leptin, but the opposite changes of expression levels were found in leprotl1, which may resist the expression of leptinR for inhibiting the function of leptin in target organ. These findings revealed details about the possible role of these genes in regulating gonadal maturation in fish species. PMID:26593912

  18. Leptin Genes in Blunt Snout Bream: Cloning, Phylogeny and Expression Correlated to Gonads Development.

    PubMed

    Zhao, Honghao; Zeng, Cong; Yi, Shaokui; Wan, Shiming; Chen, Boxiang; Gao, Zexia

    2015-11-18

    To investigate the leptin related genes expression patterns and their possible function during the gonadal development in fish, the cDNA and genomic sequences of leptin, leptin receptor (leptinR), and leptin receptor overlapping transcript like-1 (leprotl1) were cloned and their expression levels were quantified in the different gonadal development stages of Megalobrama amblycephala. The results showed that the full length cDNA sequences of leptin, leptinR and leprotl1 were 953, 3432 and 1676 bp, coding 168, 1082, and 131 amino acid polypeptides, and the genomic sequences were 1836, 28,528 and 5480 bp, which respectively had 3, 15 and 4 exons, respectively. The phylogenetic analysis revealed that three genes were relatively conserved in fish species. Quantitative real-time PCR results showed that the three genes were ubiquitously expressed in all examined tissues during the different gonadal development stages. The leptin and leptinR took part in the onset of puberty, especially in female M. amblycephala, by increasing the expression levels in brain during the stage I to III of ovary. The expression levels of leptin and leptinR had significant differences between male and female in hypothalamic-pituitary-gonadal (HPG) axis tissues (p < 0.05). The leptinR had the same variation tendency with leptin, but the opposite changes of expression levels were found in leprotl1, which may resist the expression of leptinR for inhibiting the function of leptin in target organ. These findings revealed details about the possible role of these genes in regulating gonadal maturation in fish species.

  19. Gonadal differentiation in frogs, Rana japonica and R. brevipoda, raised from UV irradiated eggs

    SciTech Connect

    Shirane, T.

    1982-10-10

    The gonadal differentiation of anurans, Rana japonica and R. brevipoda, was examined in animals raised from eggs which had been irradiated at the vegetal hemisphere with UV (9300 erg/mm2) at the 2-cell stage. In R. japonica about 70% of the larvae at stage I from the pressed and UV-irradiated eggs were germ cell free, but at a stage immediately after metamorphosis all animals had at least some germ cells, although their gonads often were extremely small and poorly differentiated. When male animals matured sexually, many of them had abnormal gonads. However, all of them were shown by artificial means to be capable of fertilization. In the nonpressed and irradiated group, no larvae were germ cell free and the animals immediately after metamorphosis showed nearly normal gonadal differentiation except for the presence of a few degenerate oocytes in the ovaries. The results in R. brevipoda were basically similar to those in R. japonica. In both species, sex ratios were determined at two stages, the first immediately after metamorphosis and the other when the animals matured, as based on gonad morphology and histology and on external sexually dimorphic characters as well. Sex ratios at these two stages in frogs from the pressed and irradiated eggs differed markedly in R. brevipoda. The ratio was normal at metamorphosis but high M/F ratios occurred when animals became mature. That sex reversal took place in this species as well as in R. japonica (in which sex-ratio deviation was not statistically significant) was supported by the sex ratios of the progenies of these supernumerary males.

  20. Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus (Teleostei)

    NASA Astrophysics Data System (ADS)

    Sun, Peng; You, Feng; Liu, Mengxia; Wu, Zhihao; Wen, Aiyun; Li, Jun; Xu, Yongli; Zhang, Peijun

    2010-03-01

    Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichthys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0-G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group ( P>0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P. olivaceus.

  1. Report of a kindred with x-linked (or autosomal dominant sex-limited) 46, XY partial gonadal dysgenesis

    SciTech Connect

    Fechner, P.Y.; Marcantonio, S.M.; Ogata, T.; Rosales, T.O.; Smith, K.D.; Goodfellow, P.N.; Migeon, C.J.; Berkovitz, G.D. )

    1993-05-01

    The condition termed 46, XY complete gonadal dysgenesis is characterized by the lack of testicular determination with resulting streak gonads, normal Mullerian structures, and female external genitalia. In the partial form, there is incomplete testicular determination with a wide range in the degree of ambiguous genitalia and sexual duct development. The authors evaluated a kindred in which a partial form of 46, XY gonadal dysgenesis occurred in four subjects from two generations. Pedigree analysis indicated an X-linked or possibly an autosomal sex-limited mode of inheritance. All affected subjects were ascertained because of ambiguous genitalia with minimal virilization. At 10 days of age, the proband had a subnormal plasma level of testosterone, and at 4 months, there was no rise in plasma T after stimulation with hCG. At laparotomy, a dysgenetic gonad was found on the right side, but no gonad was found on the left side. A vas deferens was present on the right, indicating the presence of functional leydig cells early in fetal life. In the other affected subjects, gonadal tissue was also limited to one side of the abdomen and showed poorly developed seminiferous tubules. The sex-determining region Y gene, which encodes the testis-determining factor, was present and unaltered in the genomic DNA of all affected subjects. Duplication of the distal short arm of the X-chromosome has been associated with 46, XY complete gonadal dysgenesis in some patients. In the authors studies, Southern blot analysis revealed that sequences of the distal short arm of the X-chromosome were present in single copy, excluding a large duplication in this area of the X. Several kindreds with familial 46, XY complete gonadal dysgenesis have been reported; five of them had evidence of an X-linked mode of inheritance. The authors study of a kindred with 46, XY partial gonadal dysgenesis further supports the role of an X chromosome gene in testicular determination. 44 refs., 1 fig., 3 tabs.

  2. Molecular characterization of the gonadal kisspeptin system: Cloning, tissue distribution, gene expression analysis and localization in sablefish (Anoplopoma fimbria).

    PubMed

    Fairgrieve, Marian R; Shibata, Yasushi; Smith, Elizabeth K; Hayman, Edward S; Luckenbach, J Adam

    2016-01-01

    The kisspeptin system plays pivotal roles in the regulation of vertebrate reproduction. Classically, kisspeptin produced in the brain stimulates brain gonadotropin-releasing hormone signaling, which in turn activates the pituitary-gonad axis. Expression of the kisspeptin system has also been documented in peripheral tissues, including gonads of mammals and fishes. However, the fish gonadal kisspeptin system remained uncharacterized. Herein we report identification and characterization of four kisspeptin system mRNAs (kisspeptin 1 (kiss1), kiss2, and G protein-coupled receptor 54-1 (gpr54-1) and gpr54-2) in sablefish, Anoplopoma fimbria. Sablefish predicted protein sequences were highly similar to those of other marine teleosts, but less so to freshwater teleosts. Tissue distribution analyses revealed that all four kisspeptin-system transcripts were expressed in both brain and gonad. However, kiss2 was the predominant transcript in the gonads and the only transcript detected in ovulated eggs. Ontogenetic analysis of kiss2 expression in juvenile sablefish gonads demonstrated that levels were low during sex differentiation but increased with fish size and gonadal development. Dramatic increases in kiss2 mRNA occurred during primary oocyte growth, while levels remained relatively low in testes. In situ hybridization revealed that kiss2 mRNA was localized to cytoplasm of perinucleolus stage oocytes, suggesting it could play a local role in oogenesis or could be synthesized and stored within oocytes as maternal mRNA. This represents the first study to focus on the gonadal kisspeptin system in fishes and provides important tools for further investigation of both the gonadal and brain kisspeptin systems in sablefish.

  3. Molecular characterization of the gonadal kisspeptin system: Cloning, tissue distribution, gene expression analysis and localization in sablefish (Anoplopoma fimbria).

    PubMed

    Fairgrieve, Marian R; Shibata, Yasushi; Smith, Elizabeth K; Hayman, Edward S; Luckenbach, J Adam

    2016-01-01

    The kisspeptin system plays pivotal roles in the regulation of vertebrate reproduction. Classically, kisspeptin produced in the brain stimulates brain gonadotropin-releasing hormone signaling, which in turn activates the pituitary-gonad axis. Expression of the kisspeptin system has also been documented in peripheral tissues, including gonads of mammals and fishes. However, the fish gonadal kisspeptin system remained uncharacterized. Herein we report identification and characterization of four kisspeptin system mRNAs (kisspeptin 1 (kiss1), kiss2, and G protein-coupled receptor 54-1 (gpr54-1) and gpr54-2) in sablefish, Anoplopoma fimbria. Sablefish predicted protein sequences were highly similar to those of other marine teleosts, but less so to freshwater teleosts. Tissue distribution analyses revealed that all four kisspeptin-system transcripts were expressed in both brain and gonad. However, kiss2 was the predominant transcript in the gonads and the only transcript detected in ovulated eggs. Ontogenetic analysis of kiss2 expression in juvenile sablefish gonads demonstrated that levels were low during sex differentiation but increased with fish size and gonadal development. Dramatic increases in kiss2 mRNA occurred during primary oocyte growth, while levels remained relatively low in testes. In situ hybridization revealed that kiss2 mRNA was localized to cytoplasm of perinucleolus stage oocytes, suggesting it could play a local role in oogenesis or could be synthesized and stored within oocytes as maternal mRNA. This represents the first study to focus on the gonadal kisspeptin system in fishes and provides important tools for further investigation of both the gonadal and brain kisspeptin systems in sablefish. PMID:26386183

  4. Two gonad-infecting species of Philometra (Nematoda: Philometridae) from groupers (Serranidae) off Tunisia, with a key to Philometra species infecting serranid gonads

    PubMed Central

    2016-01-01

    Based on light and scanning electron microscopical studies of nematode specimens (males and mature females) collected from the ovary of groupers (Serranidae, Perciformes) in the Mediterranean Sea off Tunisia (near Tunis and Sfax), two gonad-infecting species of Philometra Costa, 1845 (Nematoda, Philometridae) are reported: Philometra inexpectata n. sp. from the mottled grouper Mycteroperca rubra and P. jordanoi (López-Neyra, 1951) from the dusky grouper Epinephelus marginatus. Identification of both fish species was confirmed by molecular barcoding. The new species is mainly characterized by the length of equally long spicules (147–165 μm), the gubernaculum (63–93 μm long) bearing at the tip two dorsolateral lamellar parts separated from each other by a smooth median field, a V-shaped mound on the male caudal extremity, the presence of a pair of large caudal papillae located posterior to the cloaca and by the body length of the males (1.97–2.43 mm). Philometra inexpectata n. sp. is the fifth known gonad-infecting philometrid species parasitizing serranid fishes in the Mediterranean region. The males of P. jordanoi were examined by scanning electron microscopy for the first time; this detailed study revealed some new taxonomically important morphological features, such as the number and arrangement of cephalic and caudal papillae, presence of amphids and phasmids and mainly the lamellate structures at the posterior end of the gubernaculum. A key to gonad-infecting species of Philometra parasitic in serranid fishes is provided. PMID:26956219

  5. Nam Con Son Basin

    SciTech Connect

    Tin, N.T.; Ty, N.D.; Hung, L.T.

    1994-07-01

    The Nam Con Son basin is the largest oil and gas bearing basin in Vietnam, and has a number of producing fields. The history of studies in the basin can be divided into four periods: Pre-1975, 1976-1980, 1981-1989, and 1990-present. A number of oil companies have carried out geological and geophysical studies and conducted drilling activities in the basin. These include ONGC, Enterprise Oil, BP, Shell, Petro-Canada, IPL, Lasmo, etc. Pre-Tertiary formations comprise quartz diorites, granodiorites, and metamorphic rocks of Mesozoic age. Cenozoic rocks include those of the Cau Formation (Oligocene and older), Dua Formation (lower Miocene), Thong-Mang Cau Formation (middle Miocene), Nam Con Son Formation (upper Miocene) and Bien Dong Formation (Pliocene-Quaternary). The basement is composed of pre-Cenozoic formations. Three fault systems are evident in the basin: north-south fault system, northeast-southwest fault system, and east-west fault system. Four tectonic zones can also be distinguished: western differentiated zone, northern differentiated zone, Dua-Natuna high zone, and eastern trough zone.

  6. Role of PACAP in Female Fertility and Reproduction at Gonadal Level – Recent Advances

    PubMed Central

    Reglodi, Dora; Tamas, Andrea; Koppan, Miklos; Szogyi, Donat; Welke, Laura

    2012-01-01

    Pituitary adenylate cyclase activating polypeptide (PACAP) is a pleiotropic neuropeptide, first isolated from hypothalamic extracts, but later shown in peripheral organs, such as endocrine glands, gastrointestinal system, cardiovascular system, and reproductive organs. PACAP plays a role in fertility and reproduction. Numerous studies report on the gonadal regulatory effects of PACAP at hypothalamo-hypophyseal levels. However, the local effects of PACAP at gonadal levels are also important. The present review summarizes the effects of PACAP in the ovary. PACAP and its receptors are present in the ovary, and PACAP plays a role in germ cell migration, meiotic division, follicular development, and atresia. The autocrine-paracrine hormonal effects seem to play a regulatory role in ovulation, luteinization, and follicular atrophy. Altogether, PACAP belongs to the ovarian regulatory peptides. PMID:23248616

  7. Identification of candidate piRNAs in the gonads of Paralichthys olivaceus (Japanese flounder)

    PubMed Central

    WANG, Chun-Lei; WANG, Zhi-Peng; WANG, Jia-Qi; Li, Ming-You; CHEN, Xiao-Wu

    2016-01-01

    Piwi-interacting RNA (piRNA) plays an important role in the gonadal development and maintenance of Teleostei. In this study, piRNA libraries derived from the adult gonads of Japanese flounder (Paralichthys olivaceus) were generated using next-generation sequencing technology. Using zebrafish piRNAs as a reference, 5 865 unique candidate piRNAs were identified; 289 candidate piRNA clusters (PRCs) were generated from the above piRNAs. Among the isolated candidate PRCs, a total of 38 ovary-specific, 45 ovary-bias, 24 testis-specific, and 131 testis-bias PRCs were found. The relative expression levels of seven PRCs were validated through quantitative reverse transcription-polymerase chain reaction. The results of this study will help facilitate exploration of the development and maintenance of the phenotypic sex mechanism in P. olivaceus. PMID:27686790

  8. Hypothalamic-pituitary-gonadal axis in thalassemic patients with secondary amenorrhea.

    PubMed

    De Sanctis, V; Vullo, C; Katz, M; Wonke, B; Hoffbrand, A V; Bagni, B

    1988-10-01

    Eight thalassemic patients, aged 24-35 years, who developed amenorrhea 2-15 years after menarche, were studied. Mean basal serum LH and FSH levels and the peak levels after gonadotropin-releasing hormone were significantly less than corresponding values in normal controls. All patients showed low basal serum levels of estradiol and six had a poor or absent response to human menopausal gonadotropin. One subject had intact pituitary-gonadal function and one patient had an impaired LH and FSH response to gonadotropin-releasing hormone in the presence of a significant increase of estradiol after human menopausal gonadotropin stimulation. The findings regarding pituitary hormones other than gonadotropins suggest that iron overload damages tropic cells unequally and inconsistently. We conclude that both pituitary and gonadal damage may be responsible for the secondary amenorrhea in thalassemic patients.

  9. 46 XX pure gonadal dysgenesis: an infrequent cause of primary amenorrhoea

    PubMed Central

    Pertusa, Salvador; Palacios, Ana

    2009-01-01

    Amenorrhoea can be primary or secondary. Primary amenorrhoea is a relatively common problem among teenage girls. They usually consult their paediatrician or family doctor. This condition is present in patients with normal secondary sexual characteristics but no menarche by 16 years of age, or patients who have not had menstrual flow by age 14 and are lacking normal secondary sexual characteristics. Gonadal dysgenesis is an infrequent cause for primary amenorrhoea. In this paper, the case of a 16-year-old girl whose mother consulted their family doctor because of worries about her daughter’s lack of menarche is presented. A blood test showed elevated levels of follicle stimulating hormone (FSH) and luteinising hormone (LH) and low levels of oestradiol. An abdominal ultrasound was abnormal. A diagnostic laparoscopy with biopsy of both gonads was performed. Replacement hormonal therapy was applied resulting in normal menstruations after few months. An early diagnosis is extremely important. PMID:21686785

  10. Effects of tributyltin on metamorphosis and gonadal differentiation of Xenopus laevis at environmentally relevant concentrations.

    PubMed

    Shi, Huahong; Zhu, Pan; Guo, Suzhen

    2014-05-01

    Tributyltin (TBT), a well known endocrine disruptor, has high teratogenicity to embryos of amphibian (Xenopus tropicalis). An amphibian metamorphosis assay (AMA) and a complete AMA (CAMA) were conducted for TBT. In AMA, the body weight, the snout-to-vent length and the hind limb length of X. laevis tadpoles were decreased in tributyltin chloride (TBTCl; 12.5-200 ng/L) treatment groups after 7 days exposure. TBT greatly retarded the development of tadpoles, decreased the number of follicle and induced thyroid follicle cell hyperplasia after 19 days exposure. In CAMA, 10 and 100 ng/L TBTCl led to various malformations of gonad, including intersex, segmental aplasia and multiple ovary cavities of X. laevis following exposure from stages 46 to stage 66. The sex ratio was male-biased in TBT treatment groups. These results suggest that TBT delayed the metamorphosis, inhibited the growth of tadpoles and disrupted the gonadal differentiation of X. laevis at environmentally relevant concentrations.

  11. Effects of tributyltin on metamorphosis and gonadal differentiation of Xenopus laevis at environmentally relevant concentrations.

    PubMed

    Shi, Huahong; Zhu, Pan; Guo, Suzhen

    2014-05-01

    Tributyltin (TBT), a well known endocrine disruptor, has high teratogenicity to embryos of amphibian (Xenopus tropicalis). An amphibian metamorphosis assay (AMA) and a complete AMA (CAMA) were conducted for TBT. In AMA, the body weight, the snout-to-vent length and the hind limb length of X. laevis tadpoles were decreased in tributyltin chloride (TBTCl; 12.5-200 ng/L) treatment groups after 7 days exposure. TBT greatly retarded the development of tadpoles, decreased the number of follicle and induced thyroid follicle cell hyperplasia after 19 days exposure. In CAMA, 10 and 100 ng/L TBTCl led to various malformations of gonad, including intersex, segmental aplasia and multiple ovary cavities of X. laevis following exposure from stages 46 to stage 66. The sex ratio was male-biased in TBT treatment groups. These results suggest that TBT delayed the metamorphosis, inhibited the growth of tadpoles and disrupted the gonadal differentiation of X. laevis at environmentally relevant concentrations. PMID:22903176

  12. Pdgfr-α mediates testis cord organization and fetal Leydig cell development in the XY gonad

    PubMed Central

    Brennan, Jennifer; Tilmann, Christopher; Capel, Blanche

    2003-01-01

    During testis development, the rapid morphological changes initiated by Sry require the coordinate integration of many signaling pathways. Based on the established role of the platelet-derived growth factor (PDGF) family of ligands and receptors in migration, proliferation, and differentiation of cells in various organ systems, we have investigated the role of PDGF in testis organogenesis. Analysis of expression patterns and characterization of the gonad phenotype in Pdgfr-α−/− embryos identified PDGFR-α as a critical mediator of signaling in the early testis at multiple steps of testis development. Pdgfr-α−/− XY gonads displayed disruptions in the organization of the vasculature and in the partitioning of interstitial and testis cord compartments. Closer examination revealed severe reductions in characteristic XY proliferation, mesonephric cell migration, and fetal Leydig cell differentiation. This work identifies PDGF signaling through the α receptor as an important event downstream of Sry in testis organogenesis and Leydig cell differentiation. PMID:12651897

  13. From Incidentaloma to Suspicion of Malignancy: The Diverse Clinical Presentation of Gonadal Schistosomiasis mansoni

    PubMed Central

    Almeida, Laiana do Carmo; de Oliveira, Marbele Guimarães; Castro Pereira, Fábio Meira; de Bessa Júnior, José

    2013-01-01

    Schistosomiasis is the second most widespread parasitic disease in the world, second only to malaria. The usual places the Schistosoma mansoni can be found in are the rectal and sigmoidal venules, as well as other segments of the large intestine of men. It may also be present in other ectopic topographies. Gonadal schistosomiasis is an unusual presentation of Schistosomiasis mansoni and its different clinical signs and symptoms disrupt correct diagnosis and culminate in surgical treatment that is, in most cases, unnecessary. In this study, we report four cases of gonadal Schistosomiasis mansoni, two in the ovary and two in the testicles. These cases were clinically investigated as a bacterial infection, a benign neoplasm, and a suspected cancer, whilst one of them was an incidentaloma. PMID:24392230

  14. The social interactions of adult conspecifics with an adult XY gonadal dysgenetic chacma baboon (Papio ursinus).

    PubMed

    Bielert, C

    1984-03-01

    Two separate behavioral studies on an XY gonadal dysgenetic chacma baboon were carried out. In the first experiment the focal subject was treated identically as the control females by her adult male test partners. In contrast to the controls in this experiment the dysgenetic animal reciprocated the agonistic behaviors directed by the males toward her. In the second study intact and castrated males as well as ovariectomized females served as controls for the dysgenetic subject in tests with ovariectomized adult females. The stimulus females presented more to both classes of males than either the subject females or the gonadal dysgenetic individual, suggesting that the focal subject was treated by other female conspecifics as a female.

  15. Gonadal Development, Spawning and Plasma Sex Steroid Levels of the Indoor Cultured Grunt, Hapalogenys nitens

    PubMed Central

    Kang, Hee Woong; Cho, Jae-Kwon; Son, Maeng-Hyun; Park, Jong Youn; Hong, Chang Gi; Chung, Jae Seung; Chung, Ee-Yung

    2015-01-01

    The gonadosomatic index (GSI), gonadal development and changes in hormones in plasma level of the indoor cultured grunt (Hapalogenys nitens) were investigated by histological study from August 2011 to October 2012. The GSI showed similar trends with gonad developmental stages during the culture periods. Changes in plasma level of estradiol-17β of female H. nitens reached the highest value before the spawning period, and seasonal changes in plasma level of estradiol-17β were similar in trends of oocyte developments and GSI changes. Testosterone levels of male H. nitens reached the highest value before and after the spent stage. Ovarian developmental stages of H. nitens could be classified into early growing stage, late growing stage, mature stage, ripe and spawning stage, recovery and resting stage. The testicular developmental stages could be divided into growing stage, mature stage, ripe and spent stage, and recovery and resting stage. PMID:25949208

  16. Identification of candidate piRNAs in the gonads of Paralichthys olivaceus (Japanese flounder).

    PubMed

    Wang, Chun-Lei; Wang, Zhi-Peng; Wang, Jia-Qi; Li, Ming-You; Chen, Xiao-Wu

    2016-09-18

    Piwi-interacting RNA (piRNA) plays an important role in the gonadal development and maintenance of Teleostei. In this study, piRNA libraries derived from the adult gonads of Japanese flounder (Paralichthys olivaceus) were generated using next-generation sequencing technology. Using zebrafish piRNAs as a reference, 5 865 unique candidate piRNAs were identified; 289 candidate piRNA clusters (PRCs) were generated from the above piRNAs. Among the isolated candidate PRCs, a total of 38 ovary-specific, 45 ovary-bias, 24 testis-specific, and 131 testis-bias PRCs were found. The relative expression levels of seven PRCs were validated through quantitative reverse transcription-polymerase chain reaction. The results of this study will help facilitate exploration of the development and maintenance of the phenotypic sex mechanism in P. olivaceus. PMID:27686790

  17. [The effects of antipsychotic treatment on the hypothalamo-pituitary-gonadal (HPG) axis in patients with schizophrenia].

    PubMed

    Wyszogrodzka-Kucharska, Anna; Rabe-Jabłońska, Jolanta; Kostulski, Adrian

    2003-01-01

    The functioning of Hypothalamic-Pituitary-Gonadal axis is commonly affected during a course of antipsychotic therapy. This paper presents epidemiology, possible cause and management of hormonal disturbances during antipsychotic treatment in patients with schizophrenia.

  18. EFFECTS OF INCUBATION TEMPERATURE AND ESTROGEN EXPOSURE ON AROMATASE ACTIVITY IN THE BRAIN AND GONADS OF EMBRYONIC ALLIGATORS

    EPA Science Inventory

    During embryogenesis, incubation temperature and the hormonal environment influence gonadal differentiation of some reptiles, including all crocodilians. Current evidence suggests that aromatase, the enzyme that converts androgens to estrogens, has a role in sexual differentiatio...

  19. Identification of Gender-specific Transcripts by Microarray in Gonad Tissue of Larval and Juvenile Xenopus tropicalis

    EPA Science Inventory

    Amphibian model species Xenopus tropicalis is currently being utilized by EPA in the development of a standardized in vivo reproductive toxicity assay. Perturbations to the hypothalamic-pituitary-gonadal axis from exposure to endocrine disrupting compounds during larval develop...

  20. Global DNA Methylation Changes in Nile Tilapia Gonads during High Temperature-Induced Masculinization

    PubMed Central

    Wang, Hui; Li, Ning

    2016-01-01

    In some fish species, high or low temperature can switch the sex determination mechanisms and induce fish sex reversal when the gonads are undifferentiated. During this high or low temperature-induced sex reversal, the expressions of many genes are altered. However, genome-wide DNA methylation changes in fish gonads after high or low temperature treatment are unclear. Herein, we compared the global DNA methylation changes in the gonads from control females (CF), control males (CM), high temperature-treated females (TF), and high temperature-induced males (IM) from the F8 family of Nile tilapia (Oreochromis niloticus) using methylated DNA immunoprecipitation sequencing. The DNA methylation level in CF was higher than that in CM for various chromosomes. Both females and males showed an increase in methylation levels on various chromosomes after high-temperature induction. We identified 64,438 (CF/CM), 63,437 (TF/IM), 98,675 (TF/CF), 235,270 (IM/CM) and 119,958 (IM/CF) differentially methylated regions (DMRs) in Nile tilapia gonads, representing approximately 0.70% (CF/CM), 0.69% (TF/IM), 1.07% (TF/CF), 2.56% (IM/CM), and 1.30% (IM/CF)of the length of the genome. A total of 89 and 65 genes that exhibited DMRs in their gene bodies and promoters were mapped to the Nile tilapia genome. Furthermore, more than half of the genes with DMRs in the gene body in CF/CM were also included in the IM/CM, TF/CF, TF/IM, and IM/CF groups. Additionally, many important pathways, including neuroactive ligand-receptor interaction, extracellular matrix-receptor interaction, and biosynthesis of unsaturated fatty acids were identified. This study provided an important foundation to investigate the molecular mechanism of high temperature-induced sex reversal in fish species. PMID:27486872

  1. Social cues elicit sexual behavior in subordinate Damaraland mole-rats independent of gonadal status.

    PubMed

    Carter, Sara N; Goldman, Bruce D; Goldman, Sharry L; Freeman, David A

    2014-01-01

    Damaraland mole-rats (Fukomys damarensis) are among a small number of eusocial mammals. Eusociality is a social system where only a few individuals within a colony engage in direct reproduction, while remaining subordinate members are non-breeders and support reproductive efforts of breeding individuals. Inbreeding avoidance precludes mating between subordinate siblings and between offspring and parents. Interestingly, non-breeders readily attempt to mate with unrelated opposite-sex individuals. This is unusual since the non-breeding females do not attain puberty while in their natal colony. Based on this finding, the present study investigated the role of the gonads in the regulation of mating behaviors in this species and identified the mechanism of inbreeding avoidance. Gonadal-intact and gonadectomized non-breeders from different colonies were removed from their colonies and tested for the expression of sexual behavior. Results indicated that gonadal status had only minor effects on the expression of sexual behavior in either males or females. In a second experiment, sexual behaviors were absent between opposite-sex siblings so long as they had frequent contact with each other; however, following 5 weeks of separation, sexual behavior between these siblings was robustly expressed. Thus, Damaraland mole-rats avoid establishing mating relationships with familiar individuals but will readily mate with unfamiliar individuals of the opposite sex, with genetic relatedness apparently playing little role. The initiation of sexual behavior in Damaraland mole-rats does not require the presence of the gonads, but does require that the members of the pair have not been in contact with one another for at least several weeks.

  2. Anti-Müllerian hormone is a gonadal cytokine with two circulating forms and cryptic actions.

    PubMed

    McLennan, Ian S; Pankhurst, Michael W

    2015-09-01

    Anti-Müllerian hormone (AMH) is a multi-faceted gonadal cytokine. It is present in all vertebrates with its original function in phylogeny being as a regulator of germ cells in both sexes, and as a prime inducer of the male phenotype. Its ancient functions appear to be broadly conserved in mammals, but with this being obscured by its overt role in triggering the regression of the Müllerian ducts in male embryos. Sertoli and ovarian follicular cells primarily release AMH as a prohormone (proAMH), which forms a stable complex (AMHN,C) after cleavage by subtilisin/kexin-type proprotein convertases or serine proteinases. Circulating AMH is a mixture of proAMH and AMHN,C, suggesting that proAMH is activated within the gonads and putatively by its endocrine target-cells. The gonadal expression of the cleavage enzymes is subject to complex regulation, and the preliminary data suggest that this influences the relative proportions of proAMH and AMHN,C in the circulation. AMH shares an intracellular pathway with the bone morphogenetic protein (BMP) and growth differentiation factor (GDF) ligands. AMH is male specific during the initial stage of development, and theoretically should produce male biases throughout the body by adding a male-specific amplification of BMP/GDF signalling. Consistent with this, some of the male biases in neuron number and the non-sexual behaviours of mice are dependent on AMH. After puberty, circulating levels of AMH are similar in men and women. Putatively, the function of AMH in adulthood maybe to add a gonadal influence to BMP/GDF-regulated homeostasis.

  3. Adrenal axis activation by chronic social stress fails to inhibit gonadal function in male rats.

    PubMed

    Lemaire, V; Taylor, G T; Mormède, P

    1997-11-01

    Stress in males via the hypothalamic-pituitary-adrenal (HPA) axis may set into motion varied physiological alterations, including dysfunction of the hypothalamic-pituitary-gonadal (HPG) axis. However, the influence of the HPA on the HPG axis may not always be inhibitory. Presence or absence of stimuli of sexual significance that typically activates the HPG axis may alter the influence of the adrenal axis on gonadal axes. In this project, we used male rats and chronic social stimulation that included brief or extended periods with female rats to examine HPA-HPG axes interactions. In experiment 1, we used intact males and a 'chronic social stress' paradigm developed in our previous research that induces social instability by daily changing the membership of group-housed males with females. Thymus weight was reduced and corticosterone levels were marginally increased by chronic social stress, indicating a HPA axis hyperactivity. The HPG axis was also activated as shown by the increased weight of the androgen-sensitive sex structures. These results indicate that when these two axes are stimulated together, neither interferes with nor suppresses activities of the other. Implants of corticosterone pellets to adrenalectomized animals that maintained constant, high corticosterone levels failed to reverse the gonadal hyperactivity induced by sexual stimulation. In a second experiment, we studied the influence of different intensity of sexual stimulations on HPA-HPG axes interactions. Increased corticosterone levels and adrenal weight, indicating a HPA hyperactivity, failed to inhibit HPG hyperactivity as measured by the increased sexual organs weight, whatever the sexual intensity of the stimulation. This work demonstrates that the gonadal axis is freed from suppression when sexual stimulation occurs together with stress. The general conclusion is that the nature of complex social settings is important in determining interactions between the two neuroendocrine axes.

  4. Autoimmune diseases of the adrenal glands, parathyroid glands, gonads, and hypothalamic-pituitary axis.

    PubMed

    Muir, A; Maclaren, N K

    1991-09-01

    Autoimmunity directed against the adrenal glands, parathyroid glands, gonads, and hypothalamic-pituitary axis can arise in isolation or as part of a polyglandular autoimmune syndrome. Affected patients can be asymptomatic, but they may also suffer significant morbidity or even mortality. Currently, treatment is restricted largely to hormone replacement when end-organ destruction is almost complete. As our understanding of the pathogenesis of autoimmune endocrinopathies improves, it is probable that early patient detection will become practical and trials of protective immunotherapies entertained.

  5. Social regulation of gene expression in the hypothalamic-pituitary-gonadal axis.

    PubMed

    Maruska, Karen P; Fernald, Russell D

    2011-12-01

    Reproduction is a critically important event in every animals' life and in all vertebrates is controlled by the brain via the hypothalamic-pituitary-gonadal (HPG) axis. In many species, this axis, and hence reproductive fitness, can be profoundly influenced by the social environment. Here, we review how the reception of information in a social context causes genomic changes at each level of the HPG axis.

  6. Pituitary and gonadal responsiveness is enhanced during GnRH-induced puberty.

    PubMed

    Spratt, D I; Crowley, W F

    1988-05-01

    We hypothesized that the hypothalamic gonadotropin-releasing hormone (GnRH) signal that initiates sexual maturation is further amplified at both the pituitary and gonadal levels during puberty. To test this theory, six GnRH-deficient men were monitored during administration of exogenous GnRH at a physiological frequency for greater than or equal to 9 mo. GnRH doses were progressively increased until normal testosterone (T) concentrations and secondary sexual development were achieved. This "optimized" dose of GnRH was then sustained for at least 6 mo to allow maturation of the hypothalamic-pituitary-gonadal axis. The GnRH dose was then progressively decreased to a level that had been unable to stimulate normal T secretion before sexual maturation. Changes in pituitary responsiveness were analyzed in four of the six men by comparing gonadotropin responses to identical doses of GnRH before and after sexual maturation. Mean serum luteinizing hormone and follicle-stimulating hormone levels as well as luteinizing hormone pulse amplitudes were greater after the induction of sexual maturation than before despite identical doses of GnRH. Both pituitary and gonadal responsiveness was then analyzed in the remaining two subjects by choosing periods of evaluation where endogenous gonadotropin levels were matched before and after the period of sexual maturation. Serum T concentrations were greater after sexual maturation than before despite equivalent gonadotropin input to the testes and LH pulse amplitudes. Thus the testicular responsiveness to gonadotropins increased during sexual maturation. After initiation of puberty by GnRH secretion, amplification at both the pituitary and gonadal levels contributes to sexual maturation in the human.

  7. Effect of gestational antiandrogen treatment on Dicer1 expression in the porcine fetal gonads.

    PubMed

    Knapczyk-Stwora, Katarzyna; Belej, Agnieszka; Grzesiak, Malgorzata; Slomczynska, Maria

    2015-10-01

    Recently, we have demonstrated that flutamide-induced androgen deficiency during fetal life led to changes in gene expression that affected both testicular functions and follicular formation. It is known that microRNA-mediated genes regulation is essential for gonadal development and function. Thus, the aim of the present study was to examine whether prenatal flutamide exposure influences expression of Dicer1, an enzyme involved in microRNA maturation, in gonads of porcine fetuses during mid- and late gestation. Pregnant gilts were injected with flutamide (50mg/day/kg b.w.) or corn oil (controls) between days 43-49, 83-89 or 101-107 of gestation. The fetal gonads were obtained on gestational day 50 (GD50), 90 (GD90) or 108 (GD108). To assess Dicer1 mRNA expression real-time PCR were performed. Furthermore, immunohistochemical Dicer1 localization was conducted. In testes from flutamide treated fetuses, increased Dicer1 mRNA expression was observed in the GD50 and GD108 groups, but decreased in the GD90 group. Dicer1 was immunolocalized in the fetal Leydig cells in both control and flutamide-treated groups. In fetal ovaries, antiandrogen treatment increased Dicer1 mRNA level in the GD50 and GD90 groups. In control and flutamide-exposed groups, Dicer1 was localized in the germ cells within oogonia/oocyte nests as well as in the granulosa cells and oocytes of forming follicles. Concluding, diminished androgen action during gestation induces changes in Dicer1 mRNA expression, which may affect post-transcriptional gene regulation via miRNAs in porcine fetal gonads. However, it seems that androgens exert diverse biological effects depending on the gestational period. PMID:26433267

  8. [Effects of cadmium on metamorphism and gonad differentiation in Rana chensinensis].

    PubMed

    Huang, Min-Yi; Wang, Hong-Yuan; Zhang, Yu-Hui

    2010-06-01

    200 tadpoles of Rana chensinensis at stage 26 - 27 were exposed to 0.05, 0.1, 0.2 or 0.4 mg/L Cd2+ in tap water respectively until they're fully metamorphic after which the heteromorphic young frogs in different treatments were anatomized, females and males were identified through gonad observation, and the female ratio was calculated. Localization of estrogen receptors (ER) in liver cells was investigated in different treatments using immunocytochemistry. The results showed that Cd2+ might induce limb abnormality, however, there was little correlation between abnormality rate and cadmium concentration in lower Cd2+ levels except for a higher limb abnormality ratio in the 0.4 mg/L group. On the other hand, Cd2+ could affect gonad differentiation. Compared to the control group, the proportion of female population increased in the 0.05 mg/L group and decreased in the 0.1, 0.2 and 0.4 mg/L ones. The sex rate in the 0.2 mg/L group is significantly different from that in the control group. Hermaphrodite gonads appeared in the two treatments with 0.2 mg/L and 0.4 mg/L of Cd2+. Additionally, ER expression was positive in both cytoplasm and nucleolus of liver cells in Cd2+ treated groups. But, there was no linear relationship between ER expressions levels and the concentration of Cd2+. These results suggested that cadmium can influence tadpole metamorphosis and gonad development by affecting the secretion of sex hormone.

  9. Global DNA Methylation Changes in Nile Tilapia Gonads during High Temperature-Induced Masculinization.

    PubMed

    Sun, Li-Xue; Wang, Yi-Ya; Zhao, Yan; Wang, Hui; Li, Ning; Ji, Xiang Shan

    2016-01-01

    In some fish species, high or low temperature can switch the sex determination mechanisms and induce fish sex reversal when the gonads are undifferentiated. During this high or low temperature-induced sex reversal, the expressions of many genes are altered. However, genome-wide DNA methylation changes in fish gonads after high or low temperature treatment are unclear. Herein, we compared the global DNA methylation changes in the gonads from control females (CF), control males (CM), high temperature-treated females (TF), and high temperature-induced males (IM) from the F8 family of Nile tilapia (Oreochromis niloticus) using methylated DNA immunoprecipitation sequencing. The DNA methylation level in CF was higher than that in CM for various chromosomes. Both females and males showed an increase in methylation levels on various chromosomes after high-temperature induction. We identified 64,438 (CF/CM), 63,437 (TF/IM), 98,675 (TF/CF), 235,270 (IM/CM) and 119,958 (IM/CF) differentially methylated regions (DMRs) in Nile tilapia gonads, representing approximately 0.70% (CF/CM), 0.69% (TF/IM), 1.07% (TF/CF), 2.56% (IM/CM), and 1.30% (IM/CF)of the length of the genome. A total of 89 and 65 genes that exhibited DMRs in their gene bodies and promoters were mapped to the Nile tilapia genome. Furthermore, more than half of the genes with DMRs in the gene body in CF/CM were also included in the IM/CM, TF/CF, TF/IM, and IM/CF groups. Additionally, many important pathways, including neuroactive ligand-receptor interaction, extracellular matrix-receptor interaction, and biosynthesis of unsaturated fatty acids were identified. This study provided an important foundation to investigate the molecular mechanism of high temperature-induced sex reversal in fish species. PMID:27486872

  10. Gonadal sex differentiation and effects of dietary methyltestosterone treatment in sablefish (Anoplopoma fimbria).

    PubMed

    Luckenbach, J Adam; Fairgrieve, William T

    2016-02-01

    Methods for sex control are needed to establish monosex aquaculture of sablefish (Anoplopoma fimbria). Here we conducted the first characterization of sex differentiation by histology and hormonal sex reversal experiment in sablefish. Ovarian differentiation was first discernible at ~80 mm fork length (FL) and characterized by development of lamellar structures and onset of meiosis. Testes exhibited a dual-lobe appearance over much of their length and remained non-meiotic until males were ≥520 mm FL (2 years post-fertilization). Juveniles with undifferentiated gonads were provided diets containing 0 (control), 5 or 50 mg 17α-methyltestosterone (MT)/kg for 2 months. Following treatment, controls possessed either ovaries or non-meiotic testes, whereas MT-treated fish exhibited meiotic testes (60% of the fish), intersex gonads (~30%), or gonads that appeared sterile (~10%). A genetic sex marker revealed that all intersex fish were genetic females, although other females appeared to be completely sex reversed (i.e., neomales). One year after treatment, MT-treated fish possessed non-meiotic testes similar to control males or intersex gonads with reduced ovarian features, presumably due to atresia following MT withdrawal. Milt collected from neomales and genetic males 3 years post-treatment permitted sperm motility analyses; however, neomale sperm were virtually immotile. These results demonstrated that sablefish are differentiated gonochorists and that MT treatment from 76 to 196 mm FL induced permanent masculinization of a portion of the genetic females, but acquisition of sperm motility was impaired. Earlier administration of MT may be necessary to sex reverse a higher proportion of genetic females and reduce negative effects on fertility.

  11. Comprehensive transcriptomic analysis of the process of gonadal sex differentiation in the turbot (Scophthalmus maximus).

    PubMed

    Ribas, L; Robledo, D; Gómez-Tato, A; Viñas, A; Martínez, P; Piferrer, F

    2016-02-15

    The turbot is a flatfish with a ZW/ZZ sex determination system but with a still unknown sex determining gene(s), and with a marked sexual growth dimorphism in favor of females. To better understand sexual development in turbot we sampled young turbot encompassing the whole process of gonadal differentiation and conducted a comprehensive transcriptomic study on its sex differentiation using a validated custom oligomicroarray. Also, the expression profiles of 18 canonical reproduction-related genes were studied along gonad development. The expression levels of gonadal aromatase cyp19a1a alone at three months of age allowed the accurate and early identification of sex before the first signs of histological differentiation. A total of 56 differentially expressed genes (DEG) that had not previously been related to sex differentiation in fish were identified within the first three months of age, of which 44 were associated with ovarian differentiation (e.g., cd98, gpd1 and cry2), and 12 with testicular differentiation (e.g., ace, capn8 and nxph1). To identify putative sex determining genes, ∼4.000 DEG in juvenile gonads were mapped and their positions compared with that of previously identified sex- and growth-related quantitative trait loci (QTL). Although no genes mapped to the previously identified sex-related QTLs, two genes (foxl2 and 17βhsd) of the canonical reproduction-related genes mapped to growth-QTLs in linkage group (LG) 15 and LG6, respectively, suggesting that these genes are related to the growth dimorphism in this species. PMID:26586209

  12. Unexpected finding of an intact distal vagina in an infant with mixed gonadal dysgenesis

    PubMed Central

    Cabrera, Susanne M.; Alvarez, Rudy; Kaefer, Martin N.; Eugster, Erica A.; Nebesio, Todd D.

    2014-01-01

    Mixed gonadal dysgenesis (MGD) is a form of sex chromosome disorder of sex development with large phenotypic variability. Patients with MGD typically have asymmetric and ambiguous genitalia with a combination of Müllerian and Wolffian duct derivatives. Prenatal androgen exposure results in variable degrees of phallic enlargement and a urogenital sinus. Here, we report an infant with ambiguous genitalia due to MGD. Despite marked evidence of prenatal androgen exposure, there was a completely intact distal vagina. PMID:22145487

  13. [Effects of cadmium on metamorphism and gonad differentiation in Rana chensinensis].

    PubMed

    Huang, Min-Yi; Wang, Hong-Yuan; Zhang, Yu-Hui

    2010-06-01

    200 tadpoles of Rana chensinensis at stage 26 - 27 were exposed to 0.05, 0.1, 0.2 or 0.4 mg/L Cd2+ in tap water respectively until they're fully metamorphic after which the heteromorphic young frogs in different treatments were anatomized, females and males were identified through gonad observation, and the female ratio was calculated. Localization of estrogen receptors (ER) in liver cells was investigated in different treatments using immunocytochemistry. The results showed that Cd2+ might induce limb abnormality, however, there was little correlation between abnormality rate and cadmium concentration in lower Cd2+ levels except for a higher limb abnormality ratio in the 0.4 mg/L group. On the other hand, Cd2+ could affect gonad differentiation. Compared to the control group, the proportion of female population increased in the 0.05 mg/L group and decreased in the 0.1, 0.2 and 0.4 mg/L ones. The sex rate in the 0.2 mg/L group is significantly different from that in the control group. Hermaphrodite gonads appeared in the two treatments with 0.2 mg/L and 0.4 mg/L of Cd2+. Additionally, ER expression was positive in both cytoplasm and nucleolus of liver cells in Cd2+ treated groups. But, there was no linear relationship between ER expressions levels and the concentration of Cd2+. These results suggested that cadmium can influence tadpole metamorphosis and gonad development by affecting the secretion of sex hormone. PMID:20672415

  14. Stabilization of beta-catenin in XY gonads causes male-to-female sex-reversal.

    PubMed

    Maatouk, Danielle M; DiNapoli, Leo; Alvers, Ashley; Parker, Keith L; Taketo, Makoto M; Capel, Blanche

    2008-10-01

    During mammalian sex determination, expression of the Y-linked gene Sry shifts the bipotential gonad toward a testicular fate by upregulating a feed-forward loop between FGF9 and SOX9 to establish SOX9 expression in somatic cells. We previously proposed that these signals are mutually antagonistic with counteracting signals in XX gonads and that a shift in the balance of these factors leads to either male or female development. Evidence in mice and humans suggests that the male pathway is opposed by the expression of two signals, WNT4 and R-SPONDIN-1 (RSPO1), that promote the ovarian fate and block testis development. Both of these ligands can activate the canonical Wnt signaling pathway. Duplication of the distal portion of chromosome 1p, which includes both WNT4 and RSPO1, overrides the male program and causes male-to-female sex reversal in XY patients. To determine whether activation of beta-catenin is sufficient to block the testis pathway, we have ectopically expressed a stabilized form of beta-catenin in the somatic cells of XY gonads. Our results show that activation of beta-catenin in otherwise normal XY mice effectively disrupts the male program and results in male-to-female sex-reversal. The identification of beta-catenin as a key pro-ovarian and anti-testis signaling molecule will further our understanding of the mechanisms controlling sex determination and the molecular mechanisms that lead to sex-reversal. PMID:18617533

  15. Nutrient composition and antioxidant activity of gonads of sea urchin Stomopneustes variolaris.

    PubMed

    Archana, Ayyagari; Babu, K Ramesh

    2016-04-15

    The study investigated, for the first time, proximate nutritional composition and antioxidant activity of gonads from the sea urchin, Stomopneustes variolaris, inhabiting the coastal area of Visakhapatnam (India). Moisture, ash, proteins, lipids and carbohydrate content were 77.53%±0.80, 3.76%±0.25, 12.10%±0.41, 4.98%±0.36 and 1.63%±0.18, respectively, based on dry weight. The gonads were rich in essential amino acids (ca. 32.1% of total amino acids) with the most predominant being phenylalanine, lysine and valine. The essential to non-essential amino acid ratio was 0.5. Polyunsaturated fatty acids (PUFA) constituted 22.01%±2.2 of total fatty acids. The ω6:ω3 ratio was 0.94. Total phenol content of the gonad was 9.90±0.01 mg GAE/g and the IC50 of the extract, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, was 57.81 μg/ml. PMID:26616993

  16. Chronic exogenous kisspeptin administration accelerates gonadal development in basses of the genus Morone.

    PubMed

    Beck, Benjamin H; Fuller, S Adam; Peatman, Eric; McEntire, Matthew E; Darwish, Ahmed; Freeman, Donald W

    2012-07-01

    The present study assesses the effects of chronic administration of peptides to fish, termed kisspeptins, which are the products of the KISS1 and KISS2 genes, and have been shown to control the development of puberty in animals. Using ecologically and commercially important species (white bass, Morone chrysops, striped bass, Morone saxatilis, and their hybrid) as comparative models, we determined that repeated bi-weekly injections (over 7 weeks) differentially accelerate puberty, as evidenced by increases in the prevalence of spermatozoa in the testes of juvenile fish. Moreover, in sexually mature fish, kisspeptin treatment led to increased gonad weight, gonadosomatic index, and spermatocrit in some white and striped bass. Additionally, mature white bass treated with kisspeptins showed an advancement in oocyte development as determined by histological examination. These gonadal changes occurred in the absence of any photothermal manipulation or hormone injections. To date, this is the first description of kisspeptin-mediated pubertal initiation in fish, and the first evidence that kisspeptins could modulate gonad maturation. Although it remains to be determined how kisspeptins may best be utilized in practice, our findings are a basis for future studies to characterize the molecular underpinnings of the KISS system in various fish species. PMID:22497780

  17. The effect of latitude on photoperiodic control of gonadal maturation, regression and molt in birds.

    PubMed

    Dawson, Alistair

    2013-09-01

    Photoperiod is the major cue used by birds to time breeding seasons and molt. However, the annual cycle in photoperiod changes with latitude. Within species, for temperate and high latitude species, gonadal maturation and breeding start earlier at lower latitudes but regression and molt both occur at similar times at different latitudes. Earlier gonadal maturation can be explained simply by the fact that considerable maturation occurs before the equinox when photoperiod is longer at lower latitudes - genetic differences between populations are not necessary to explain earlier breeding at lower latitudes. Gonadal regression is caused either by absolute photorefractoriness or, in some species with long breeding seasons, relative photorefractoriness. In either case, the timing of regression and molt cannot be explained by absolute prevailing photoperiod or rate of change in photoperiod - birds appear to be using more subtle cues from the pattern of change in photoperiod. However, there may be no difference between absolute and relative photorefractory species in how they utilise the annual cycle in photoperiod to time regression. PMID:23770215

  18. Hypothalamic-pituitary-gonadal function in men with cirrhosis of the liver.

    PubMed

    Mowat, N A; Edwards, C R; Fisher, R; McNeilly, A S; Green, J R; Dawson, A M

    1976-05-01

    Hypothalamic-pituitary-gonadal function was studied in 37 cirrhotic males, 25 of whom were alcoholic. Irrespective of aetiology, cirrhotic patients had significantly reduced free testosterone concentrations. Despite low free testosterone concentrations and reduced or absent spermatogenesis, basal levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were normal in nearly all patients, suggesting impaired function of the hypothalamic-pituitary-gonadal axis. In 14 cirrhotic men, seven of whom had gynaecomastia, the ability of the pituitary to secrete LH and FSH in response to exogenous gonadotrophin releasing-hormone (LH/FSH-RH) was asssessed. A normal LH response to LH/FSH-RH was obtained in patients without gynaecomastia. An exaggerated LH response was found in four of seven with gynaecomastia, suggesting Leydig cell failure. The Leydig cell response to exogenous gonadotrophin in eight consecutive cirrhotic patients was probably abnormal but difficult to interpret as all but one were within conventionally accepted limits of normality. The patients without gynaecomastia gave a normal or minimally exaggerated FSH response to LH/FSH-RH. Six of seven with gynaecomastia gave a markedly exaggerated response suggesting failure of spermatogenesis, and all tested were either azoospermic of oligospermic. The single patient with a normal FSH response had a normal sperm count. The pituitary cells can therefore respond to LH/RSH-RH and the Leydig cells of the testes show some response to exogenous gonadotrophin. Similar abnormalities in hypothalamic-pituitary-gonadal function have recently been described in patients with normal liver function on chronic oestrogen therapy.

  19. Sex, Stress, and Mood Disorders: At the Intersection of Adrenal and Gonadal Hormones

    PubMed Central

    Fernández-Guasti, A.; Fiedler, J. L.; Herrera, L.; Handa, R. J.

    2012-01-01

    The risk for neuropsychiatric illnesses has a strong sex bias, and for major depressive disorder (MDD), females show a more than 2-fold greater risk compared to males. Such mood disorders are commonly associated with a dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis. Thus, sex differences in the incidence of MDD may be related with the levels of gonadal steroid hormone in adulthood or during early development as well as with the sex differences in HPA axis function. In rodents, organizational and activational effects of gonadal steroid hormones have been described for the regulation of HPA axis function and, if consistent with humans, this may underlie the increased risk of mood disorders in women. Other developmental factors, such as prenatal stress and prenatal overexposure to glucocorticoids can also impact behaviors and neuroendocrine responses to stress in adulthood and these effects are also reported to occur with sex differences. Similarly, in humans, the clinical benefits of antidepressants are associated with the normalization of the dysregulated HPA axis, and genetic polymorphisms have been found in some genes involved in controlling the stress response. This review examines some potential factors contributing to the sex difference in the risk of affective disorders with a focus on adrenal and gonadal hormones as potential modulators. Genetic and environmental factors that contribute to individual risk for affective disorders are also described. Ultimately, future treatment strategies for depression should consider all of these biological elements in their design. PMID:22581646

  20. Carotenoid extraction from the gonad of the scallop Nodipecten nodosus (Linnaeus, 1758) (Bivalvia: Pectinidae).

    PubMed

    Suhnel, S; Lagreze, F; Ferreira, J F; Campestrini, L H; Maraschin, M

    2009-02-01

    In marine bivalve mollusks, unsaturated molecules called carotenoids are present in the natural diet and play an important role in different biological process, especially in reproduction. In order to gain more insights into these compounds in Nodipecten nodosus it was necessary to develop a suitable protocol for extraction of carotenoids from the gonads. Female gonads of cultured scallops (75 mm length) were lyophilized and macerated in liquid N2. To verify the effect of composition in organosolvents on the extracting solutions, two organic solvents were tested: acetone and hexane (Ac = O:Hex) at four ratios, 1:1, 1:3, 1:5, and 2:3, in four static extraction times: 0, 5, 10, and 15 minutes. Total carotenoids and astaxanthin contents were determined in the crude extracts by UV-visible spectrophotometry and high performance liquid chromatography (HPLC), respectively. Triplicate aliquots of 50 mg were used for each treatment. The results indicated that the best single extraction (0.312 +/- 0.016 microg carotenoids/mg) was attained with Ac = O: Hex 1:3, for 15 minutes. Through exhaustive extraction methodology (10x), a superior yield (0.41 +/- 0.001 microg carotenoids/mg) was obtained from a gonad sample in comparison to the highest value found for a single extraction. Astaxanthin content was reduced by 8.6% in carotenoid extract preservation assay, i.e., -18 degrees C, 26 days incubation, under N2 atmosphere.

  1. Final height and gonad function after total body irradiation during childhood.

    PubMed

    Couto-Silva, A-C; Trivin, C; Esperou, H; Michon, J; Baruchel, A; Lemaire, P; Brauner, R

    2006-09-01

    Short stature and gonad failure can be a side effect of total body irradiation (TBI). The purpose of the study was to evaluate the factors influencing final height and gonad function after TBI. Fifty young adults given TBI during childhood were included. Twenty-seven had been treated with growth hormone (GH). Those given single 10 Grays (Gy) or fractionated 12 Gy TBI had similar characteristics, GH peaks, final heights and gonad function. After the end of GH treatment, 11/20 patients evaluated had GH peak >10 microg/l. Final height was <-2s.d. in 29 (58%). The height loss between TBI and final height (2.4+/-1.1 s.d.) was greater in those who were younger when irradiated (P<0.0001). When the GH-treated and -untreated patients were analyzed separately, this loss was correlated with the age at TBI at 4-8 years for the GH-treated and at 6-8 years for the untreated. Boys showed negative correlations between testicular volume and plasma follicle-stimulating hormone (FSH, P=0.0008) and between plasma FSH and inhibin B (P=0.005) concentrations. We concluded that the indications for GH treatment should be mainly based on the age at irradiation, taking into account the GH peak. The plasma FSH and inhibin B concentrations may predict sperm function.

  2. Regulation of meiotic entry and gonadal sex differentiation in the human: normal and disrupted signaling.

    PubMed

    Jørgensen, Anne; Rajpert-De Meyts, Ewa

    2014-08-01

    Meiosis is a unique type of cell division that is performed only by germ cells to form haploid gametes. The switch from mitosis to meiosis exhibits a distinct sex-specific difference in timing, with female germ cells entering meiosis during fetal development and male germ cells at puberty when spermatogenesis is initiated. During early fetal development, bipotential primordial germ cells migrate to the forming gonad where they remain sexually indifferent until the sex-specific differentiation of germ cells is initiated by cues from the somatic cells. This irreversible step in gonadal sex differentiation involves the initiation of meiosis in fetal ovaries and prevention of meiosis in the germ cells of fetal testes. During the last decade, major advances in the understanding of meiosis regulation have been accomplished, with the discovery of retinoic acid as an inducer of meiosis being the most prominent finding. Knowledge about the molecular mechanisms regulating meiosis signaling has mainly been established by studies in rodents, while this has not yet been extensively investigated in humans. In this review, the current knowledge about the regulation of meiosis signaling is summarized and placed in the context of fetal gonad development and germ cell differentiation, with emphasis on results obtained in humans. Furthermore, the consequences of dysregulated meiosis signaling in humans are briefly discussed in the context of selected pathologies, including testicular germ cell cancer and some forms of male infertility. PMID:25372763

  3. cep-1/p53-dependent dysplastic pathology of the aging C. elegans gonad.

    PubMed

    McGee, Mathew D; Day, Nicholas; Graham, Jill; Melov, Simon

    2012-04-01

    The C. elegans germline and somatic gonad are actively developing until the animal reaches adulthood, and then continue to undergo striking changes as the animal ages. Reported changes include a depletion of available sperm, a decrease in oocyte quality up till mid-life, a reduction in germline nuclei, a decrease in fertility, and an accumulation of DNA in the midbody of aging C. elegans. Here, we have focused on the aging gonad in old animals, and show in detail that the aging gonad undergoes a massive uterine growth composed of endoreduplicating oocytes, yolk, and expanses of chromatin. We use a novel series of imaging techniques in combination with histological methodology for reconstructing aged worms in 3-dimensions, and show in old animals growing masses swelling inside the uterus to occupy most of the diameter of the worm. We link this accelerated growth to the cep-1/p53 tumor suppressor. Because cep-1 is required for DNA damage induced apoptosis, and daf-2 limits longevity, these results suggest a role for age-related DNA damage in dysplastic uterine growths, which in some respects resemble premalignant changes that can occur in aging mammals.

  4. Puberty and Gonadal Hormones: Role in Adolescent-typical Behavioral Alterations

    PubMed Central

    Varlinskaya, Elena I.; Vetter-O’Hagen, Courtney S.; Spear, Linda P.

    2012-01-01

    Adolescence is characterized by a variety of behavioral alterations, including elevations in novelty-seeking and experimentation with alcohol and other drugs of abuse. Some adolescent-typical neurobehavioral alterations may depend upon pubertal rises in gonadal hormones, whereas others may be unrelated to puberty. Using a variety of approaches, studies in laboratory animals have not revealed clear relationships between pubertal-related changes and adolescent- or adult-typical behaviors that are not strongly sexually dimorphic. Data reviewed suggest surprisingly modest influences of gonadal hormones on alcohol intake, alcohol preference and novelty-directed behaviors. Gonadectomy in males (but not females) increased ethanol intake in adulthood following surgery either pre-pubertally or in adulthood, with these increases in intake largely reversed by testosterone replacement in adulthood, supporting an activational role of androgens in moderating ethanol intake in males. In contrast, neither pre-pubertal nor adult gonadectomy influenced sensitivity to the social inhibitory or aversive effects of ethanol when indexed via conditioned taste aversions, although gonadectomy at either age altered the microstructure of social behavior of both males and females. Unexpectedly, the pre-pubertal surgical manipulation process itself was found to increase later ethanol intake, decrease sensitivity to ethanol’s social inhibitory effects, attenuate novelty-directed behavior and lower social motivation, with gonadal hormones being necessary for these long-lasting effects of early surgical perturbations. PMID:23998677

  5. Origin and Differentiation of Androgen-Producing Cells in the Gonads.

    PubMed

    Potter, Sarah J; Kumar, Deepti Lava; DeFalco, Tony

    2016-01-01

    Sexual reproduction is dependent on the activity of androgenic steroid hormones to promote gonadal development and gametogenesis. Leydig cells of the testis and theca cells of the ovary are critical cell types in the gonadal interstitium that carry out steroidogenesis and provide key androgens for reproductive organ function. In this chapter, we will discuss important aspects of interstitial androgenic cell development in the gonad, including: the potential cellular origins of interstitial steroidogenic cells and their progenitors; the molecular mechanisms involved in Leydig cell specification and differentiation (including Sertoli-cell-derived signaling pathways and Leydig-cell-related transcription factors and nuclear receptors); the interactions of Leydig cells with other cell types in the adult testis, such as Sertoli cells, germ cells, peritubular myoid cells, macrophages, and vascular endothelial cells; the process of steroidogenesis and its systemic regulation; and a brief discussion of the development of theca cells in the ovary relative to Leydig cells in the testis. Finally, we will describe the dynamics of steroidogenic cells in seasonal breeders and highlight unique aspects of steroidogenesis in diverse vertebrate species. Understanding the cellular origins of interstitial steroidogenic cells and the pathways directing their specification and differentiation has implications for the study of multiple aspects of development and will help us gain insights into the etiology of reproductive system birth defects and infertility. PMID:27300177

  6. Toying with fate: Redirecting the differentiation of adrenocortical progenitor cells into gonadal-like tissue

    PubMed Central

    Röhrig, Theresa; Pihlajoki, Marjut; Ziegler, Ricarda; Cochran, Rebecca S.; Schrade, Anja; Schillebeeckx, Maximiliaan; Mitra, Robi D.; Heikinheimo, Markku; Wilson, David B.

    2014-01-01

    Cell fate decisions are integral to zonation and remodeling of the adrenal cortex. Animal models exhibiting ectopic differentiation of gonadal-like cells in the adrenal cortex can shed light on the molecular mechanisms regulating steroidogenic cell fate. In one such model, prepubertal gonadectomy (GDX) of mice triggers the formation of adrenocortical neoplasms that resemble luteinized ovarian stroma. Transcriptomic analysis and genome-wide DNA methylation mapping have identified genetic and epi-genetic markers of GDX-induced adrenocortical neoplasia. Members of the GATA transcription factor family have emerged as key regulators of cell fate in this model. Expression of Gata4 is pivotal for the accumulation of gonadal-like cells in the adrenal glands of gonadectomized mice, whereas expression of Gata6 limits the spontaneous and GDX-induced differentiation of gonadal-like cells in the adrenal cortex. Additionally, Gata6 is essential for proper development of the adrenal X-zone, a layer analogous to the fetal zone of the human adrenal cortex. The relevance of these observations to developmental signaling pathways in the adrenal cortex, to other animal models of altered adrenocortical cell fate, and to human diseases is discussed. PMID:25498963

  7. Prey resources before spawning influence gonadal investment of female, but not male, white crappie

    USGS Publications Warehouse

    Bunnell, D.B.; Thomas, S.E.; Stein, R.A.

    2007-01-01

    In this study, an outdoor pool experiment was used to evaluate the effect of prey resources during 4 months before spawning on the gonadal investments of male and female white crappie Pomoxis annularis, a popular freshwater sportfish that exhibits erratic recruitment. Fish were assigned one of three feeding treatments: starved, fed once every 5 days (intermediate) or fed daily (high). All measurements of male testes (i.e. wet mass, energy density and spermatocrit) were similar across treatments. Conversely, high-fed females produced larger ovaries than those of intermediate-fed and starved fish, and invested more energy in their ovaries than starved fish. Compared to pre-experiment fish, starved and intermediate-fed females appeared to increase their ovary size by relying on liver energy stores (‘capital’ spawning). Conversely, high-fed females increased liver and gonad mass, implying an ‘income’-spawning strategy (where gonads are built from recently acquired energy). Fecundity did not differ among treatments, but high-fed fish built larger eggs than those starved. Females rarely ‘skipped’ spawning opportunities when prey resources were low, as only 8% of starved females and 8% of intermediate-fed females lacked vitellogenic eggs. These results suggest that limited prey resources during the months before spawning can limit ovary production, which, in turn, can limit reproductive success of white crappies.

  8. Effects of warm acclimation on physiology and gonad development in the sea urchin Evechinus chloroticus.

    PubMed

    Delorme, Natalí J; Sewell, Mary A

    2016-08-01

    The physiology of the New Zealand sea urchin Evechinus chloroticus was evaluated through feeding, respiration, growth and gonad growth in adult animals acclimated for 90days at 18°C (annual mean temperature) and 24°C (ambient summer temperature (21°C) +3°C). Measured parameters with representative rates of assimilation efficiency were used to calculate scope for growth (SfG) for each treatment. All physiological parameters were negatively affected at 24°C, showing a decrease in feeding rate which coincided with negative growth and gonad development at the end of the acclimation period, and a decrease in respiration rate suggesting metabolic depression. Histology of gonad samples after the acclimation period also showed no gametic material in animals acclimated at 24°C. All animals acclimated at 24°C had negative growth, differing from the calculated SfG which indicated that the animals had sufficient energy for production. The results suggest that calculated SfG in echinoderms should be used together with actual measurements of growth in individuals as, by itself, SfG may underestimate the actual effect of ocean warming when animals are exposed to stressful conditions. Overall, considering the total loss of reproductive output observed in E. chloroticus at higher temperatures, an increase in seawater temperature could dramatically influence the persistence of northern populations of this species, leading to flow-on effects in the subtidal ecosystem. PMID:27043875

  9. Effects of atrazine on metamorphosis, growth, and gonadal development in the green frog (Rana clamitans).

    PubMed

    Coady, Katherine; Murphy, Margaret; Villeneuve, Daniel; Hecker, Markus; Jones, Paul; Carr, James; Solomon, Keith; Smith, Ernest; Van Der Kraak, Glen; Kendall, Ronald; Giesy, John

    2004-06-25

    Embryos of the green frog (Rana clamitans) were collected from the field and exposed to 1 of 6 water-borne treatments for 273 d (mid July 2001 to mid April 2002). The treatments were 0, 10, or 25 microg/L atrazine, 0.005% ethanol (EtOH), or 0.1 mg/L estradiol or dihydrotestosterone carried in 0.005% EtOH. Treatments were applied in a static renewal system with a 50% test solution replacement approximately every 3 d. Following the exposure period, tadpoles were reared in freshwater until metamorphosis or until study termination (at d 506). Time to initiate and complete metamorphosis, stage-specific mortality, length and weight at metamorphosis, and gross morphology and histology of the gonads were examined. At environmentally relevant concentrations, atrazine did not consistently affect growth or metamorphosis. Compared to controls, the length of the larval period was greater in tadpoles exposed to 10 microg/L atrazine. However, the length of the larval period was not markedly different between tadpoles in the control and 25 microg/L atrazine treatments. Neither gross gonadal morphology nor histopathology of the gonads in postmetamorphic frogs was significantly altered in response to atrazine exposure. This study provides evidence that environmentally relevant concentrations of atrazine do not adversely affect the growth or reproductive development of R. clamitans.

  10. Involvement of Antizyme Characterized from the Small Abalone Haliotis diversicolor in Gonadal Development.

    PubMed

    Li, Wei-Dong; Huang, Min; Lü, Wen-Gang; Chen, Xiao; Shen, Ming-Hui; Li, Xiang-Min; Wang, Rong-Xia; Ke, Cai-Huan

    2015-01-01

    The small abalone Haliotis diversicolor is an economically important mollusk that is widely cultivated in Southern China. Gonad precocity may affect the aquaculture of small abalone. Polyamines, which are small cationic molecules essential for cellular proliferation, may affect gonadal development. Ornithine decarboxylase (ODC) and antizyme (AZ) are essential elements of a feedback circuit that regulates cellular polyamines. This paper presents the molecular cloning and characterization of AZ from small abalone. Sequence analysis showed that the cDNA sequence of H. diversicolor AZ (HdiODCAZ) consisted of two overlapping open reading frames (ORFs) and conformed to the +1 frameshift property of the frame. Thin Layer chromatography (TLC) analysis suggested that the expressed protein encoded by +1 ORF2 was the functional AZ that targets ODC to 26S proteasome degradation. The result demonstrated that the expression level of AZ was higher than that of ODC in the ovary of small abalone. In addition, the expression profiles of ODC and AZ at the different development stages of the ovary indicated that these two genes might be involved in the gonadal development of small abalone. PMID:26313647

  11. Puberty and gonadal hormones: role in adolescent-typical behavioral alterations.

    PubMed

    Varlinskaya, Elena I; Vetter-O'Hagen, Courtney S; Spear, Linda P

    2013-07-01

    This article is part of a Special Issue "Puberty and Adolescence". Adolescence is characterized by a variety of behavioral alterations, including elevations in novelty-seeking and experimentation with alcohol and other drugs of abuse. Some adolescent-typical neurobehavioral alterations may depend upon pubertal rises in gonadal hormones, whereas others may be unrelated to puberty. Using a variety of approaches, studies in laboratory animals have not revealed clear relationships between pubertal-related changes and adolescent- or adult-typical behaviors that are not strongly sexually dimorphic. Data reviewed suggest surprisingly modest influences of gonadal hormones on alcohol intake, alcohol preference and novelty-directed behaviors. Gonadectomy in males (but not females) increased ethanol intake in adulthood following surgery either pre-pubertally or in adulthood, with these increases in intake largely reversed by testosterone replacement in adulthood, supporting an activational role of androgens in moderating ethanol intake in males. In contrast, neither pre-pubertal nor adult gonadectomy influenced sensitivity to the social inhibitory or aversive effects of ethanol when indexed via conditioned taste aversions, although gonadectomy at either age altered the microstructure of social behavior of both males and females. Unexpectedly, the pre-pubertal surgical manipulation process itself was found to increase later ethanol intake, decrease sensitivity to ethanol's social inhibitory effects, attenuate novelty-directed behavior and lower social motivation, with gonadal hormones being necessary for these long-lasting effects of early surgical perturbations.

  12. The effect of latitude on photoperiodic control of gonadal maturation, regression and molt in birds.

    PubMed

    Dawson, Alistair

    2013-09-01

    Photoperiod is the major cue used by birds to time breeding seasons and molt. However, the annual cycle in photoperiod changes with latitude. Within species, for temperate and high latitude species, gonadal maturation and breeding start earlier at lower latitudes but regression and molt both occur at similar times at different latitudes. Earlier gonadal maturation can be explained simply by the fact that considerable maturation occurs before the equinox when photoperiod is longer at lower latitudes - genetic differences between populations are not necessary to explain earlier breeding at lower latitudes. Gonadal regression is caused either by absolute photorefractoriness or, in some species with long breeding seasons, relative photorefractoriness. In either case, the timing of regression and molt cannot be explained by absolute prevailing photoperiod or rate of change in photoperiod - birds appear to be using more subtle cues from the pattern of change in photoperiod. However, there may be no difference between absolute and relative photorefractory species in how they utilise the annual cycle in photoperiod to time regression.

  13. Involvement of Antizyme Characterized from the Small Abalone Haliotis diversicolor in Gonadal Development

    PubMed Central

    Lü, Wen-Gang; Chen, Xiao; Shen, Ming-Hui; Li, Xiang-Min; Wang, Rong-Xia; Ke, Cai-Huan

    2015-01-01

    The small abalone Haliotis diversicolor is an economically important mollusk that is widely cultivated in Southern China. Gonad precocity may affect the aquaculture of small abalone. Polyamines, which are small cationic molecules essential for cellular proliferation, may affect gonadal development. Ornithine decarboxylase (ODC) and antizyme (AZ) are essential elements of a feedback circuit that regulates cellular polyamines. This paper presents the molecular cloning and characterization of AZ from small abalone. Sequence analysis showed that the cDNA sequence of H. diversicolor AZ (HdiODCAZ) consisted of two overlapping open reading frames (ORFs) and conformed to the +1 frameshift property of the frame. Thin Layer chromatography (TLC) analysis suggested that the expressed protein encoded by +1 ORF2 was the functional AZ that targets ODC to 26S proteasome degradation. The result demonstrated that the expression level of AZ was higher than that of ODC in the ovary of small abalone. In addition, the expression profiles of ODC and AZ at the different development stages of the ovary indicated that these two genes might be involved in the gonadal development of small abalone. PMID:26313647

  14. Influence of gonadal hormones on odours emitted by male meadow voles (Microtus pennsylvanicus).

    PubMed

    Ferkin, M H; Gorman, M R; Zucker, I

    1992-08-01

    Free-living male meadow voles (Microtus pennsylvanicus) emit odours that are attractive to females at the beginning, but not at the end, of the breeding season. The effect of gonadal hormones on female-attractant cues was examined in males born and reared in long (14 h light day-1) and short (10 h light day-1) photoperiods that simulate daylengths in the breeding and nonbreeding seasons, respectively. Gonadectomy affected the attractant properties of odours emitted by long photoperiod, but not short photoperiod, males. Long photoperiod females preferred odours of intact rather than those of gonadectomized long photoperiod males, and odours of gonadectomized long photoperiod males rather than those of intact short photoperiod males. Females did not show a preference between the odours of intact and castrated short photoperiod males. Gonadal hormone replacement in males affected female responses to the odours emitted by long photoperiod, but not short photoperiod, gonadectomized males. Long photoperiod females did not display a preference between odours of intact long photoperiod males and gonadectomized long photoperiod males treated with testosterone or oestradiol. We conclude that in spring and summer gonadal hormones increase attractiveness of male odours; this effect may require aromatization of testosterone to oestradiol. Substrates that control attractiveness of odour cues in male voles appear to be unresponsive to androgens during the nonbreeding season. PMID:1404090

  15. Nutrient composition and antioxidant activity of gonads of sea urchin Stomopneustes variolaris.

    PubMed

    Archana, Ayyagari; Babu, K Ramesh

    2016-04-15

    The study investigated, for the first time, proximate nutritional composition and antioxidant activity of gonads from the sea urchin, Stomopneustes variolaris, inhabiting the coastal area of Visakhapatnam (India). Moisture, ash, proteins, lipids and carbohydrate content were 77.53%±0.80, 3.76%±0.25, 12.10%±0.41, 4.98%±0.36 and 1.63%±0.18, respectively, based on dry weight. The gonads were rich in essential amino acids (ca. 32.1% of total amino acids) with the most predominant being phenylalanine, lysine and valine. The essential to non-essential amino acid ratio was 0.5. Polyunsaturated fatty acids (PUFA) constituted 22.01%±2.2 of total fatty acids. The ω6:ω3 ratio was 0.94. Total phenol content of the gonad was 9.90±0.01 mg GAE/g and the IC50 of the extract, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, was 57.81 μg/ml.

  16. The ecological and physiological bases of variation in the phenology of gonad growth in an urban and desert songbird.

    PubMed

    Davies, Scott; Lane, Samuel; Meddle, Simone L; Tsutsui, Kazuyoshi; Deviche, Pierre

    2016-05-01

    Birds often adjust to urban areas by advancing the timing (phenology) of vernal gonad growth. However, the ecological and physiological bases of this adjustment are unclear. We tested whether the habitat-related disparity in gonad growth phenology of male Abert's towhees, Melozone aberti, is due to greater food availability in urban areas of Phoenix, Arizona USA or, alternatively, a habitat-related difference in the phenology of key food types. To better understand the physiological mechanism underlying variation in gonad growth phenology, we compared the activity of the reproductive system at all levels of hypothalamo-pituitary-gonadal (HPG) axis. We found no habitat-associated difference in food availability (ground arthropod biomass), but, in contrast to the seasonal growth of leaves on desert trees, the leaf foliage of urban trees was already developed at the beginning of our study. Multiple estimates of energetic status did not significantly differ between the non-urban and urban towhees during three years that differed in the habitat-related disparity in gonad growth and winter precipitation levels. Thus, our results provide no support for the hypothesis that greater food abundance in urban areas of Phoenix drives the habitat-related disparity in gonad growth phenology in Abert's towhees. By contrast, they suggest that differences in the predictability and magnitude of change in food availability between urban and desert areas of Phoenix contribute to the observed habitat-related disparity in gonad growth. Endocrine responsiveness of the gonads may contribute to this phenomenon as desert - but not urban - towhees had a marked plasma testosterone response to GnRH challenge.

  17. Robot-assisted laparoscopic hysterectomy, gonadal biopsy, and orchiopexies in an infant with persistent mullerian duct syndrome.

    PubMed

    Wu, Jonathan A; Hsieh, Michael H

    2014-04-01

    An infant born with hypospadias and no palpable gonads was diagnosed with persistent mullerian duct syndrome (PMDS) based on history, physical examination, laboratory testing, and radiologic imaging. A robot-assisted laparoscopic hysterectomy, right gonadal biopsy, and bilateral orchiopexies were performed without incident. Final pathology confirmed the diagnosis of PMDS. To our knowledge, this is only the second report of PMDS managed through a robot-assisted laparoscopic approach. PMID:24246315

  18. Depression among hospitalized and non-hospitalized gonadal cancer patients in tertiary care public hospitals in Karachi.

    PubMed

    Yousaf, Tahira; Zadeh, Zainab Fotowwat

    2015-03-01

    The study aimed at determining the differences in the levels of depression between hospitalized and non-hospitalized Gonadal cancer patients in tertiary care public hospitals in Karachi. The present study was conducted at the Jinnah Postgraduate Medical Centre and Civil Hospital, Karachi, from July to October 2009. One hundred adult patients diagnosed with Gonadal cancer volunteered for the study. Cases with any other co-morbidity were excluded. Urdu version of Siddiqui Shah Depression Scale (SSDS) was administered. Purposive and snowball sampling methods were used for data collection. The ages of participants in the sample ranged from 20 to 27 years with the mean age of 23.85 years. The participants belonged to the lower and middle classes. Out of the 30 hospitalized gonadal cancer patients 40% were moderately depressed and 60% were severely depressed, whereas out of 70 non-hospitalized gonadal cancer patients 74.3% were mildly depressed, 24.3% were moderately depressed and only 1.4% were severely depressed, which clearly indicated that the depression level of hospitalized gonadal cancer patients was high as compared to non-hospitalized gonadal cancer patients.

  19. Gonadal Disorder in the Thinlip Grey Mullet (Liza ramada, Risso 1827) as a Biomarker of Environmental Stress in Surface Waters

    PubMed Central

    Tancioni, Lorenzo; Caprioli, Riccardo; Dawood Al-Khafaji, Ayad Hantoosh; Mancini, Laura; Boglione, Clara; Ciccotti, Eleonora; Cataudella, Stefano

    2015-01-01

    The aim of this study was to evaluate the use of gonadal alterations in the thinlip grey mullet (Liza ramada) as a biological indicator in assessing aquatic ecosystems health, with particular emphasis to river ecosystems exposed to sewage discharges. For this purpose, the reproductive status and the presence of gonadal alterations were studied in 206 mullets collected from two sites on the low course of the Tiber River, downstream of a large urban sewage treatment plant and in the estuarine area, and from an uncontaminated pond considered as reference site. Intersex and irregularly shaped gonads were observed in 20.8% of the mullets from the most polluted site, and intersex gonads in 10.3% of those from the estuarine area. No alterations were detected in the fish from the reference site, which also showed distinct stages of gonadal development. Conversely, unclear stages of testicular and ovary development were observed in the fish from the two polluted river sites. The results of this study suggest that L. ramada may represent a sentinel species in environmental risk assessment and support the use of gonadal alterations of this species as a bioindicator for extensive monitoring of pollution in lower stretches of rivers and estuarine areas. PMID:25664693

  20. A case of 46, XY DSD presenting as a crossed ectopic gonad with a contralateral sliding inguinal hernia.

    PubMed

    Fukui, Shinji; Watanabe, Masato; Yoshino, Kaoru

    2012-12-01

    A three-month-old boy was referred to our facility for the treatment of a right impalpable testis, left inguinal hernia, and penoscrotal hypospadias with asymmetric external genitalia. The left gonad was palpated in the left scrotum. The chromosomal study revealed a normal male 46, XY karyotype. Operative findings showed that the right streak gonad, uterus, and fallopian tubes were in the wall of the left hernia sac, forming a sliding hernia. Laparoscopy confirmed that the right gonadal vessels had crossed to the left internal inguinal ring. Herniorrhaphy was done and the right streak gonad, uterus, and fallopian tubes were excised. An exploration of the left gonad revealed an ovotestis. The ovary was removed, and a left testicular biopsy was simultaneously performed. A one-stage hypospadias repair using Koyanagi procedure was also performed. The pathological findings showed an ovarian stroma in the right gonad and left ovary. Only Sertoli cells were detected in the biopsied specimen from the left testis. PMID:23217900

  1. Histological and histochemical analysis of the gonadal development of males and females of Armases rubripes (Rathbun 1897) (Crustacea, Brachyura, Sesarmidae).

    PubMed

    Santos, C M; Lima, G V; Nascimento, A A; Sales, A; Oshiro, L M Y

    2009-02-01

    The objective of this study was to provide information on the histological characteristics of the gonads of male and female Armases rubripes crabs, and to try to establish a relationship between the microscopic and macroscopic stages previously identified. Thirty-six crabs were collected by hand between February 2003 and January 2004 in banks of Spartina alterniflora on Sahy Beach in Mangaratiba, Rio de Janeiro state, Brazil. The histological analysis of the ovaries of A. rubripes demonstrated a gradual process of development of the oocytes. According to their cellular characteristics, five types of cells were distinguished: oogonia, oocyte I, oocyte II, oocyte III and oocyte IV. The ovaries showed four stages during gonadal activity: stage I (rudimentary), stage II (developing or maturing), stage III (developed or mature) and stage IV (resting). The results of the histochemical analyses showed that the ovaries vary according to the gonad development stage. The histological aspect of one section of the male gonad was always the same in all of the seminiferous tubules, where the lumen of these tubules always contained spermatozoa and/or spermatids. It was not possible to characterize the three stages of gonad development in the males. This agrees with previous reports in the literature. However, in the females there was a relationship between the gonad stages distinguished macroscopically and the results obtained through the histological and histochemical analysis, due to the presence of different cell types, as well as the lysis process and reabsorption of the oocytes in spent females.

  2. Effect of cadmium on gonadal development in freshwater turtle (Trachemys scripta, Chrysemys picta) embryos.

    PubMed

    Kitana, Noppadon; Callard, Ian P

    2008-02-15

    Prior studies on painted turtle (Chrysemys picta) sub-populations near the Massachusetts Military Reservation (MMR), a Superfund site on Cape Cod, Massachusetts, USA, suggest several reproductive deficits which may be related to xenobiotics. Several heavy metals, including cadmium, have been detected in Cape Cod surface water and sediments. The present study was carried out to investigate the effect of an environmentally relevant dose of cadmium on gonadal development during the end of the germ cell migration phase and post-natal gonadal maturation in freshwater turtles. Comparison of cadmium concentration in eggs of C. picta from Cape Cod showed that eggs from the impacted site animals had significantly higher cadmium in yolk than eggs from the reference site animals (7.23 +/- 1.95 ng/g vs. 1.31 +/- 0.50 ng/g). Gonadal structure and the number of proliferating germ cells of neonates derived from eggs of adult females from these sites showed no marked difference between sites. However, apoptosis of oocytes was significantly increased in neonate C. picta from the impacted pond compared to the reference pond. The effect of an administered environmentally relevant dose of cadmium on germ cell number and oocyte apoptosis was subsequently assessed in lab-reared Trachemys scripta, a closely related freshwater turtle species. Assessment of isotopic cadmium transmission showed that 6.29% of cadmium applied to the eggshell was transmitted through the eggshell to the yolk. The results showed that the total number of germ cells in cadmium-treated (1 microg/g) embryos was less than half that found in control embryos. The reduced germ cell number in Cd-treated embryos suggests that cadmium may reduce proliferation and/or delay migration of germ cells to the genital ridge. The effects of cadmium on turtle gonadal development were found to extend into 3 months post hatch. Proliferation of oocytes was not influenced by exposure to cadmium in ovo. In contrast, apoptosis of oocytes

  3. Prenatal Testosterone Exposure Leads to Gonadal Hormone-Dependent Hyperinsulinemia and Gonadal Hormone-Independent Glucose Intolerance in Adult Male Rat Offspring.

    PubMed

    More, Amar S; Mishra, Jay S; Gopalakrishnan, Kathirvel; Blesson, Chellakkan S; Hankins, Gary D; Sathishkumar, Kunju

    2016-01-01

    Elevated testosterone levels during prenatal life lead to hyperandrogenism and insulin resistance in adult females. This study evaluated whether prenatal testosterone exposure leads to the development of insulin resistance in adult male rats in order to assess the influence of gonadal hormones on glucose homeostasis in these animals. Male offspring of pregnant rats treated with testosterone propionate or its vehicle (control) were examined. A subset of male offspring was orchiectomized at 7 wk of age and reared to adulthood. At 24 wk of age, fat weights, plasma testosterone, glucose homeostasis, pancreas morphology, and gastrocnemius insulin receptor (IR) beta levels were examined. The pups born to testosterone-treated mothers were smaller at birth and remained smaller through adult life, with levels of fat deposition relatively similar to those in controls. Testosterone exposure during prenatal life induced hyperinsulinemia paralleled by an increased HOMA-IR index in a fasting state and glucose intolerance and exaggerated insulin responses following a glucose tolerance test. Prenatal androgen-exposed males had more circulating testosterone during adult life. Gonadectomy prevented hyperandrogenism, reversed hyperinsulinemia, and attenuated glucose-induced insulin responses but did not alter glucose intolerance in these rats. Prenatal androgen-exposed males had decreased pancreatic islet numbers, size, and beta-cell area along with decreased expression of IR in gastrocnemius muscles. Gonadectomy restored pancreatic islet numbers, size, and beta-cell area but did not normalize IRbeta expression. This study shows that prenatal testosterone exposure leads to a defective pancreas and skeletal muscle function in male offspring. Hyperinsulinemia during adult life is gonad-dependent, but glucose intolerance appears to be independent of postnatal testosterone levels. PMID:26586841

  4. Effects of 17α-ethinylestradiol at different water temperatures on zebrafish sex differentiation and gonad development.

    PubMed

    Luzio, Ana; Santos, Dércia; Fontaínhas-Fernandes, António A; Monteiro, Sandra M; Coimbra, Ana M

    2016-05-01

    In the current climate change scenario, studies combining effects of water contaminants with environmental parameters, such as temperature, are essential to predict potentially harmful impacts on aquatic organisms. In zebrafish (Danio rerio), sex determination seems to have a polygenic genetic basis, which can be secondarily influenced by environmental factors, such as temperature and endocrine disrupting chemicals (EDCs). The present study aimed to evaluate the effects of the EDC 17α-ethinylestradiol (EE2), a potent synthetic estrogen, on zebrafish sex differentiation and gonad development at different water temperatures. Therefore, zebrafish raised at three distinct water temperatures (23, 28 or 33±0.5°C), were exposed to 4ng/L of EE2, from 2hours to 60days post-fertilization (dpf). Subsequently, a quantitative (stereological) assessment of zebrafish gonads was performed, at 35 and 60dpf, to identify alterations on gonadal development and differentiation. The results show that low temperature delayed general growth of zebrafish, as well as gonad differentiation and maturation, while high temperature induced an opposite effect. Moreover, sex ratio was skewed toward males when zebrafish were exposed to the high temperature. In general, EE2 exposure promoted gonad maturation in both genders, independently of the temperature. However, at the high temperature condition, exposure to EE2 induced a delay in the male gonad development, with some individuals still showing differentiating gonads at 60dpf. The findings of this study support the notion that zebrafish has a genetic sex determination mechanism highly sensitive to environmental factors and show that it is essential to study the effects of water contaminants at different climate scenarios in order to understand potential future impacts on organisms. PMID:26897088

  5. Extra-gonadal steroids modulate non-breeding territorial aggression in weakly electric fish.

    PubMed

    Jalabert, Cecilia; Quintana, Laura; Pessina, Paula; Silva, Ana

    2015-06-01

    The neuroendocrine control of intraspecific aggression is a matter of current debate. Although aggression in a reproductive context has been associated with high levels of circulating androgens in a broad range of species, it has also been shown to occur during the non-breeding season when gonads are regressed and plasma steroid hormone levels are low. In mammals and birds the aromatization of androgens into estrogens plays a key role in the regulation of aggression in both the breeding and non-breeding seasons. This is the first study in a teleost fish to explore the role of steroids in the modulation of non-breeding aggression. Gymnotus omarorum is a highly aggressive teleost fish that exhibits aggression all year-round. We analyzed male-male non-breeding agonistic behavior, compared circulating 11-Ketotestosterone (11-KT) levels between dominants and isolated males, assessed the regulatory role of aromatization of androgens into estrogens, and evaluated the gonads as a source of these sex steroids. We found that high levels of aggression occurred in the non-breeding season despite low plasma 11-KT levels, and that there was no difference in 11-KT levels between dominant and isolated males. We demonstrated that acute aromatase inhibition decreased aggression, distorted contest dynamics, and affected expected outcome. We also found that castrated individuals displayed aggressive behavior indistinguishable from non-castrated males. Our results show, for the first time in teleost fish, that territorial aggression of G. omarorum during the non-breeding season depends on a non-gonadal estrogenic pathway.

  6. Noonan syndrome: the hypothalamo-adrenal and hypothalamo-gonadal axes.

    PubMed

    Kelnar, Christopher J H

    2009-12-01

    The hypothalamo-pituitary-adrenal axis has not been studied systematically in Noonan syndrome (NS), despite potential concerns about other aspects of hypothalamo-pituitary function. While adrenarche may be delayed in children with constitutional growth of puberty and in isolated GH deficiency, this does not generally seem to be the case in hypergonadotrophic hypogonadism due to Turner syndrome (TS) and this is (anecdotally) the usual hormonal profile in NS children and adults. Precocious or 'exaggerated' adrenarche can be associated with intrauterine growth retardation and is a forerunner of syndrome X. Although NS neonates often have 'normal' birth weights, in some it can be artificially inflated by subcutaneous edema (as in TS, where intrauterine growth retardation is characteristic). Overall, however, a controlling role for adrenarche (whether precocious or delayed) in gonadarche in NS seems unlikely. Neither normally descended testes nor normal (even if delayed) pubertal development implies normal fertility in NS men. Interactions between fetal, neonatal, childhood and pubertal testis development and gonadal axis maturation are complex. There is probably a spectrum of abnormalities in NS, but most commonly primary gonadal failure and hypergonadotrophic hypogonadism - characteristic NS molecular genetic abnormalities - may be important for normal germ cell proliferation, development and migration. The identification of different gene defects facilitates understanding of NS phenotypic diversity and provides opportunities for prospective studies on gonadal and adrenal axes in better defined populations less subject to ascertainment bias. At a clinical level, more longitudinal data are still needed with regard to the natural history of pubertal timing, its tempo of progression and the pattern of pubertal growth.

  7. Endocannabinoids are Involved in Male Vertebrate Reproduction: Regulatory Mechanisms at Central and Gonadal Level.

    PubMed

    Bovolin, Patrizia; Cottone, Erika; Pomatto, Valentina; Fasano, Silvia; Pierantoni, Riccardo; Cobellis, Gilda; Meccariello, Rosaria

    2014-01-01

    Endocannabinoids (eCBs) are natural lipids regulating a large array of physiological functions and behaviors in vertebrates. The eCB system is highly conserved in evolution and comprises several specific receptors (type-1 and type-2 cannabinoid receptors), their endogenous ligands (e.g., anandamide and 2-arachidonoylglycerol), and a number of biosynthetic and degradative enzymes. In the last few years, eCBs have been described as critical signals in the control of male and female reproduction at multiple levels: centrally, by targeting hypothalamic gonadotropin-releasing-hormone-secreting neurons and pituitary, and locally, with direct effects on the gonads. These functions are supported by the extensive localization of cannabinoid receptors and eCB metabolic enzymes at different levels of the hypothalamic-pituitary-gonadal axis in mammals, as well as bonyfish and amphibians. In vivo and in vitro studies indicate that eCBs centrally regulate gonadal functions by modulating the gonadotropin-releasing hormone-gonadotropin-steroid network through direct and indirect mechanisms. Several proofs of local eCB regulation have been found in the testis and male genital tracts, since eCBs control Sertoli and Leydig cells activity, germ cell progression, as well as the acquisition of sperm functions. A comparative approach usually is a key step in the study of physiological events leading to the building of a general model. Thus, in this review, we summarize the action of eCBs at different levels of the male reproductive axis, with special emphasis, where appropriate, on data from non-mammalian vertebrates.

  8. Functional cross-talk between the hypothalamic-pituitary-gonadal and -adrenal axes.

    PubMed

    Viau, V

    2002-06-01

    Under normal conditions, the adrenal glucocorticoids, the endproduct of the hypothalamic-pituitary-adrenal (HPA) axis, provide a frontline of defence against threats to homeostasis (i.e. stress). On the other hand, chronic HPA drive and glucocorticoid hypersecretion have been implicated in the pathogenesis of several forms of systemic, neurodegenerative and affective disorders. The HPA axis is subject to gonadal influence, indicated by sex differences in basal and stress HPA function and neuropathologies associated with HPA dysfunction. Functional cross-talk between the gonadal and adrenal axes is due in large part to the interactive effects of sex steroids and glucocorticoids, explaining perhaps why several disease states linked to stress are sex-dependent. Realizing the interactive nature by which the hypothalamic-pituitary-gonadal and HPA systems operate, however, has made it difficult to model how these hormones act in the brain. Manipulation of one endocrine system is not without effects on the other. Simultaneous manipulation and assessment of both endocrine systems can overcome this problem. This dual approach in the male rat reveals that testosterone can act and interact on different aspects of basal and stress HPA function. Basal adrenocorticotropic hormone (ACTH) release is regulated by testosterone-dependent effects on arginine vasopressin synthesis, and corticosterone-dependent effects on corticotropin-releasing hormone (CRH) synthesis in the paraventricular nucleus (PVN) of the hypothalamus. In contrast, testosterone and corticosterone interact on stress-induced ACTH release and drive to the PVN motor neurones. Candidate structures mediating this interaction include several testosterone-sensitive afferents to the HPA axis, including the medial preoptic area, central and medial amygdala and bed nuclei of the stria terminalis. All of these relay homeostatic information and integrate reproductive and social behaviour. Because these modalities are affected

  9. Demasculinization and feminization of male gonads by atrazine: Consistent effects across vertebrate classes

    PubMed Central

    Hayes, Tyrone B.; Anderson, Lloyd L.; Beasley, Val R.; de Solla, Shane R.; Iguchi, Taisen; Ingraham, Holly; Kestemont, Patrick; Kniewald, Jasna; Kniewald, Zlatko; Langlois, Valerie S.; Luque, Enrique H.; McCoy, Krista A.; Muñoz-de-Toro, Mónica; Oka, Tomohiro; Oliveira, Cleida A.; Orton, Frances; Ruby, Sylvia; Suzawa, Miyuki; Tavera-Mendoza, Luz E.; Trudeau, Vance L.; Victor-Costa, Anna Bolivar; Willingham, Emily

    2015-01-01

    Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called “Hill criteria” (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause–effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a state of the art summary of the mechanisms by which atrazine acts as an endocrine disruptor to produce these effects. Atrazine demasculinizes male gonads producing testicular lesions associated with reduced germ cell numbers in teleost fish, amphibians, reptiles, and mammals, and induces partial and/or complete feminization in fish, amphibians, and reptiles. These effects are strong (statistically significant), consistent across vertebrate classes, and specific. Reductions in androgen levels and the induction of estrogen synthesis – demonstrated in fish, amphibians, reptiles, and mammals – represent plausible and coherent mechanisms that explain these effects. Biological gradients are observed in several of the cited studies, although threshold doses and patterns vary among species. Given that the effects on the male gonads described in all of these experimental studies occurred only after atrazine exposure, temporality is also met here. Thus the case for atrazine as an endocrine disruptor that demasculinizes and feminizes male vertebrates meets all nine of the “Hill criteria”. PMID:21419222

  10. Detection of a parasitic amoeba (Order Dactylopodida) in the female gonads of oysters in Brazil.

    PubMed

    Sühnel, Simone; Ivachuk, Celene da S; Schaefer, Ana L C; Pontinha, Vitor A; Martins, Maurício L; Figueras, Antonio; Meyer, Gary R; Jones, Simon R M; Stewart, Johnson C; Gurney-Smith, Helen J; Magalhães, Aimê R M; Bower, Susan M

    2014-07-01

    The impacts of oocyte parasites on the reproductive success of molluscs are largely unknown. In this study, we evaluated the presence of gonad parasites in 6 species of marine bivalve molluscs native to southern Brazil. Cultured bivalves included the mangrove oyster Crassostrea gasar (sometimes called C. brasiliana), the brown mussel Perna perna, the lion's paw scallop Nodipecten nodosus and the wing pearl oyster Pteria hirundo. Another species of mangrove oyster, C. rhizophorae, and the carib pointed venus clam Anomalocardia brasiliana (syn. A. flexuosa) were collected from the wild. Molluscs were collected in winter 2009 and summer 2010 for histopathological and molecular evaluation. An unknown ovarian parasite (UOP) was observed in histopathological sections of female gonads of C. gasar and C. rhizophorae. The UOP possessed features suggestive of amoebae, including an irregular outer membrane, frothy cytoplasm, a nucleus with a prominent central nucleolus and a closely associated basophilic parasome. PCR analysis was negative for Marteilioides chungmuensis, Perkinsus spp. and Paramoeba perurans. However, real-time PCR successfully amplified DNA from oyster gonads when using universal Paramoeba spp. primers. Also, conventional PCR amplified DNA using primers specific for Perkinsela amoebae-like organisms (syn. Perkinsiella), which are considered as endosymbionts of Parameoba spp., previously thought to be the parasome. Our results suggest that this UOP is a species of amoeba belonging to 1 of the 2 families of the order Dactylopodida, possibly related to Paramoeba spp. This study represents the first report of this type of organism in oysters. We found that C. gasar and C. rhizophorae were the most susceptible molluscs to these UOPs.

  11. Effects of simvastatin and pravastatin on gonadal function in male hypercholesterolemic patients.

    PubMed

    Dobs, A S; Miller, S; Neri, G; Weiss, S; Tate, A C; Shapiro, D R; Musliner, T A

    2000-01-01

    Inhibition of cholesterol biosynthesis by hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors could, in theory, adversely affect male gonadal function because cholesterol is a precursor of steroid hormones. The objective of this randomized double-blind trial was to compare the effects of simvastatin, pravastatin, and placebo on gonadal testosterone production and spermatogenesis. After a 6-week placebo and lipid-lowering diet run-in period, 159 male patients aged 21 to 55 years with type IIa or IIb hypercholesterolemia, low-density lipoprotein (LDL) cholesterol between 145 and 240 mg/dL, and normal basal levels of testosterone were randomly assigned to treatment with simvastatin 20 mg (n = 40), simvastatin 40 mg (n = 41), pravastatin 40 mg (n = 39), or placebo (n = 39) once daily. After 24 weeks of treatment, mean total cholesterol levels were decreased 24% to 27% and mean LDL cholesterol was decreased 30% to 34% in the 3 active-treatment groups (P < .001 for all comparisons to placebo). At 24 weeks, there were no statistically significant differences between the placebo group and any of the active-treatment groups for the change from baseline in testosterone, human chorionic gonadotropin (hCG)stimulated testosterone, free testosterone index, follicle-stimulating hormone (FSH), luteinizing hormone (LH), or sex hormone-binding globulin (SHBG). Moreover, there were no statistically significant differences at week 12 or week 24 for the change from baseline in sperm concentration, ejaculate volume, or sperm motility for any active treatment relative to placebo. Both simvastatin and pravastatin were well tolerated. In summary, we found no evidence for clinically meaningful effects of simvastatin or pravastatin on gonadal testosterone production, testosterone reserve, or multiple parameters of semen quality. PMID:10647074

  12. Males and females gonad fatty acids of the sea urchins Paracentrotus lividus and Arbacia lixula (Echinodermata)

    NASA Astrophysics Data System (ADS)

    Martínez-Pita, Inés; García, Francisco J.; Pita, María-Luisa

    2010-06-01

    The aim of this study was to analyze male and female gonad fatty acids of two sea urchin species, Paracentrotus lividus and Arbacia lixula, from the south coast of Spain. Additionally, we investigated possible differences between two locations. The ovaries of both species showed higher percentages of 14:0, 16:0, 16:1n-7, 18:2n-6, 18:3n-3 and 18:4n-3 than testes and lower levels of 18:0, 22:1n-9, 20:4n-6 and 22:5n-3. In P. lividus but not in A. lixula, the level of 20:5n-3 was higher in testes than in ovaries. These differences between sexes probably indicate different requirements of males and females during gametogenesis although the presence of a large number of gametes in the mature gonad may also have influences on fatty acid composition. Significant differences in gonad fatty acid profiles where also found when individuals of P. lividus collected at a location of the Mediterranean region were compared with specimens collected at the Atlantic coast. The most remarkable changes were the lower levels of 14:0, 18:1n-7, 20:1n-9, 20:4n-6 and 22:4n-6 and the higher values of 20:1n-11, 20:5n-3 and 22:6n-3 found in males and females of the Mediterranean specimens compared to those of the Atlantic coast. These differences probably reflect the differences in potential food sources at each location.

  13. Atrazine concentrations, gonadal gross morphology and histology in ranid frogs collected in Michigan agricultural areas.

    PubMed

    Murphy, M B; Hecker, M; Coady, K K; Tompsett, A R; Jones, P D; Du Preez, L H; Everson, G J; Solomon, K R; Carr, J A; Smith, E E; Kendall, R J; Van Der Kraak, G; Giesy, J P

    2006-03-10

    The triazine herbicide atrazine has been suggested to be a potential disruptor of normal sexual development in male frogs. The goals of this study were to collect native ranid frogs from sites in agricultural and non-agricultural areas and determine whether hypothesised atrazine effects on the gonads could be observed at the gross morphological and histological levels. Juvenile and adult green frogs (Rana clamitans), bullfrogs (R. catesbeiana) and leopard frogs (R. pipiens) were collected in the summers of 2002 and 2003. Atrazine concentrations were below the limit of quantification at non-agricultural sites, and concentrations did not exceed 2 microg/L at most agricultural sites. One concentration greater than 200 microg atrazine/L was measured once at one site in 2002. Hermaphroditic individuals with both male and female gonad tissue in either one or both gonads, were found at a low incidence at both non-agricultural and agricultural sites, and in both adults and juveniles. Testicular oocytes (TO) were found in male frogs at most of the sites, with the greatest incidence occurring in juvenile leopard frogs. TO incidence was not significantly different between agricultural and non-agricultural sites with the exception of juveniles collected in 2003. Atrazine concentrations were not significantly correlated with the incidence of hermaphroditism, but maximum atrazine concentrations were correlated with TO incidence in juvenile frogs in 2003. However, given the lack of a consistent relationship between atrazine concentrations and TO incidence, it is more likely the TOs observed in this study result from natural processes in development rather than atrazine exposure.

  14. Endocannabinoids are Involved in Male Vertebrate Reproduction: Regulatory Mechanisms at Central and Gonadal Level

    PubMed Central

    Bovolin, Patrizia; Cottone, Erika; Pomatto, Valentina; Fasano, Silvia; Pierantoni, Riccardo; Cobellis, Gilda; Meccariello, Rosaria

    2014-01-01

    Endocannabinoids (eCBs) are natural lipids regulating a large array of physiological functions and behaviors in vertebrates. The eCB system is highly conserved in evolution and comprises several specific receptors (type-1 and type-2 cannabinoid receptors), their endogenous ligands (e.g., anandamide and 2-arachidonoylglycerol), and a number of biosynthetic and degradative enzymes. In the last few years, eCBs have been described as critical signals in the control of male and female reproduction at multiple levels: centrally, by targeting hypothalamic gonadotropin-releasing-hormone-secreting neurons and pituitary, and locally, with direct effects on the gonads. These functions are supported by the extensive localization of cannabinoid receptors and eCB metabolic enzymes at different levels of the hypothalamic–pituitary–gonadal axis in mammals, as well as bonyfish and amphibians. In vivo and in vitro studies indicate that eCBs centrally regulate gonadal functions by modulating the gonadotropin-releasing hormone–gonadotropin–steroid network through direct and indirect mechanisms. Several proofs of local eCB regulation have been found in the testis and male genital tracts, since eCBs control Sertoli and Leydig cells activity, germ cell progression, as well as the acquisition of sperm functions. A comparative approach usually is a key step in the study of physiological events leading to the building of a general model. Thus, in this review, we summarize the action of eCBs at different levels of the male reproductive axis, with special emphasis, where appropriate, on data from non-mammalian vertebrates. PMID:24782832

  15. Caenorhabditis elegans SWI/SNF subunits control sequential developmental stages in the somatic gonad.

    PubMed

    Large, Edward E; Mathies, Laura D

    2014-03-20

    The Caenorhabditis elegans somatic gonadal precursors (SGPs) are multipotent progenitors that give rise to all somatic tissues of the adult reproductive system. The hunchback and Ikaros-like gene ehn-3 is expressed specifically in SGPs and is required for their development into differentiated tissues of the somatic gonad. To find novel genes involved in SGP development, we used a weak allele of ehn-3 as the basis for a reverse genetic screen. Feeding RNAi was used to screen ∼2400 clones consisting of transcription factors, signaling components, and chromatin factors. The screen identified five members of the C. elegans SWI/SNF chromatin remodeling complex as genetic enhancers of ehn-3. We characterized alleles of 10 SWI/SNF genes and found that SWI/SNF subunits are required for viability and gonadogenesis. Two conserved SWI/SNF complexes, PBAF and BAF, are defined by their unique array of accessory subunits around a common enzymatic core that includes a catalytic Swi2/Snf2-type ATPase. Tissue-specific RNAi experiments suggest that C. elegans PBAF and BAF complexes control different processes during somatic gonadal development: PBRM-1, a signature subunit of PBAF, is important for normal SGP development, whereas LET-526, the distinguishing subunit of BAF, is required for development of a differentiated cell type, the distal tip cell (DTC). We found that the SWSN-4 ATPase subunit is required for SGP and DTC development. Finally, we provide evidence that C. elegans PBAF subunits and hnd-1/dHand are important for the cell fate decision between SGPs and their differentiated sisters, the head mesodermal cells.

  16. Age, growth, and gonadal characteristics of adult bighead carp, Hypophthalmichthys nobilis, in the lower Missouri River

    USGS Publications Warehouse

    Schrank, S.J.; Guy, C.S.

    2002-01-01

    Bighead carp were introduced into Arkansas in 1973 to improve water clarity in production ponds. Bighead carp subsequently escaped aquaculture facilities in the early 1980's and dispersed into the Mississippi and Missouri rivers. The first documentation of bighead carp reproduction in the Mississippi River system was in 1989. The population has increased in the Missouri River as is evident in their increased proportion in the commercial harvest since 1990. The effect of this exotic planktivore on native ecosystems of the U.S. has not been examined. Basic biological data on bighead carp Hypophthalmichthys nobilis in the Missouri River are needed to predict potential ecological problems and provide a foundation for manipulative studies. The objectives of this study were to assess age, growth, and gonadal characteristics of bighead carp in the Missouri River. Adult bighead carp in our sample varied from age 3 to age 7 and length varied from 475 to 1050 mm. There was a large variation in length at age, and overall bighead carp exhibited fast growth. For example, mean back-calculated length at age 3 was 556 mm. The sample was dominated by bighead carp from the 1994 year class. There was no difference in gonad development (i.e., gonadal somatic index, egg diameter) between winter and spring samples. Length of male bighead carp and GSI were not significantly correlated; however, females exhibited a positive linear relationship between length and GSI. In each ovary, egg diameter frequencies exhibited a bimodal distribution, indicating protracted spawning. Mean fecundity was 226 213, with a maximum fecundity of 769 964. Bighead carp in the Missouri River have similar life history characteristics to Asian and European populations. They have become well established in the Missouri River and it is likely that dispersal and population density will increase.

  17. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    PubMed

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed.

  18. Terminology of gonadal anomalies in fish and amphibians resulting from chemical exposures.

    PubMed

    Hecker, Markus; Murphy, Margaret B; Coady, Katherine K; Villeneuve, Daniel L; Jones, Paul D; Carr, James A; Solomon, Keith R; Smith, Ernest E; Van Der Kraak, Glen; Gross, Timothy; Du Preez, Louis; Kendall, Ronald J; Giesy, John P

    2006-01-01

    Given the recent increase in the number of studies describing the ability of chemicals to exert endocrine-disrupting effects, not only in fish but in a variety of other oviparous groups such as amphibians and reptiles, there is an urgent need to harmonize the terminology currently used in describing pathological changes of the gonads. In addition to difficulties in comparing results from different studies, there is also the risk of miscommunication by using terms that imply a certain clinical relevance which may not be true for the species examined. Especially in the case of the recent and controversial issue about potential effects of the triazine herbicide atrazine on amphibians, clinical terminology has been utilized beyond its true meaning by using terms such as "chemical castration" to describe occurrence of TOs or ovarian tissue in the testis of male frogs exposed to environmental chemicals (Hayes 2004). In clinical terminology, castration is defined as the removal of the gonads or their destruction by an external influence, resulting in a nonfertile organism. However, Hayes (2004) did not investigate any possible effects on the fertility of the test animals and thus did not know if these animals were truly castrated. Similarly, terms such as intersex, hermaphrodite, and sex reversal have been used in ways that appear inappropriate with regard to their clinical meaning in a series of different studies with fish or frogs (see previous sections for a detailed discussion). To ensure the appropriate use of certain terminology in a field as controversial and complex as the study of endocrine disruption, we have attempted, in this chapter, to harmonize the terminology used to describe changes in gonadal development of vertebrates such as fish and amphibians, especially frogs (see Table 3). Where appropriate, the terminology suggested was adopted directly from the clinical terminology. However, as outlined here there are substantial differences between the

  19. The effect of selective estrogen receptor modulators on parameters of the hypothalamic-pituitary-gonadal axis.

    PubMed

    Plouffe, L; Siddhanti, S

    2001-12-01

    The SERMs currently in clinical practice or in late stages of clinical development have been studied primarily for their effects on the breast, cardiovascular, bone, and reproductive systems. The effect of SERMs on the hypothalamic-pituitary-gonadal (HPG) axis has not been the primary focus of the studies conducted thus far. However the effect of SERMs on the HPG axis and the associated regulation of endocrine parameters may play an important role in their overall clinical profile. In this review the effects of selected SERMs on the HPG axis in premenopausal women, postmenopausal women, and men are summarized.

  20. beta-thalassemia and gonadal axis: a cross-sectional, clinical study in a Greek population.

    PubMed

    Papadimas, John; Goulis, Dimitrios G; Mandala, Eudokia; Georgiadis, George; Zournatzi, Vassiliki; Tarlatzis, Basil C; Bontis, John N

    2002-01-01

    beta-thalassemia (beta-thal) is characterized by disturbances of the reproductive system. The aim of the present study was: 1) to assess the hypothalamic- pituitary-gonadal axis in patients with beta-thal in relation to their phenotype and 2) to determine prognostic features of current gonadal status. We studied 135 patients (67 males and 68 females) with beta-thal through history, physical examination, spermiograms and GnRH test. These patients were divided into beta-thal major (51 males and 62 females) and beta-thal intermedia phenotypes (16 males and 6 females). Male patients with beta-thal major were subdivided into three groups a) eugonadal (35%, Tanner's stage V, normal testicular volume, normal spermiograms, normal basal and stimulated hormone values), b) patients with hypogonadotrophic hypogonadism (HH) of late onset (24%, Tanner's stage II-V, low-normal testicular volume, abnormal spermiograms, normal basal gonadotrophin values and abnormal response to GnRH test) and c) patients with HH of early onset (41%, Tanner's stage I, small testicular volume, abnormal spermiograms, abnormal basal and stimulated hormone values). Female patients with beta-thal major were subdivided into: a) eugonadal (32%, Tanner's stage V, regular menstruation, normal basal and stimulated hormone values), b) patients with hypogonadotrophic hypogonadism (HH) of late onset (34%, Tanner's stage II-V, secondary amenorrhea, subnormal basal and stimulated gonadotrophin values) and c) patients with HH of early onset (34%, Tanner's stage I, primary amenorrhea, subnormal basal and stimulated hormone values). Patients with beta-thal intermedia were subdivided into eugonadal (75% of males, 33% of females) and hypogonadal (25% of males, 67% of females). Current gonadal status could not be predicted by means of transfusion or chelation parameters. In conclusion, beta-thal patients could be eugonadal or develop early or late onset HH. trade mark-thal intermedia patients have a more favorable

  1. The effect of increased cardiac output on luteal phase gonadal steroids: a hypothesis for runners amenorrhea.

    PubMed

    Casper, R F; Wilkinson, D; Cotterell, M A

    1984-03-01

    The beta-adrenergic agonist isoproterenol was infused intravenously for 4 hours during the midluteal phase of the cycle in six normal women. A rapid increase in cardiac output occurred for the entire duration of the isoproterenol infusion and serum estrogen and progesterone levels (but not luteinizing hormone levels) decreased significantly (P less than 0.001) to a nadir of 30% and 50% of baseline levels, respectively, suggesting increased metabolic clearance of the two steroids. We hypothesize that endurance training chronically increases metabolic clearance of gonadal steroids, resulting in abnormal negative and/or positive feedback on the hypothalamic/pituitary axis leading to the menstrual irregularities commonly seen in athletes.

  2. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    PubMed

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed. PMID:19218496

  3. Gonadal function after 12-Gy testicular irradiation in childhood acute lymphoblastic leukemia

    SciTech Connect

    Castillo, L.A.; Craft, A.W.; Kernahan, J.; Evans, R.G.; Aynsley-Green, A. )

    1990-01-01

    Gonadal function was assessed in 15 boys with acute lymphoblastic leukemia (ALL) who had received testicular irradiation. The dose to the testes was 12 Gy in 12, 15 Gy in 1, and 24 Gy in 2 cases. All of those who had received 12 or 15 Gy had normal Leydig cell function, although high levels of gonadotropins suggest subclinical Leydig cell damage. The 2 who had 24 Gy had Leydig cell failure. All who were old enough to produce a semen specimen were azoospermic.

  4. Influence of male gonadal hormones and familiarity on pregnancy interruption in prairie voles.

    PubMed

    Smale, L

    1988-08-01

    Pregnancy interruption (PI) was examined in female prairie voles, Microtus ochrogaster, exposed to stimuli from males 7 to 12 days after pairing. Urine from unfamiliar males interrupted pregnancy when placed directly on the external nares of newly mated females, but urine from familiar stud males was without effect. Castration of males did not reduce the efficacy of unfamiliar male urine in interrupting pregnancy. The neuroendocrine system of female prairie voles responded selectively to male urine as a function of its familiarity; the efficacy of male stimuli leading to PI was not dependent on gonadal hormones. PMID:3061485

  5. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay.

    PubMed

    Lu, Zhigang; Sessler, Florian; Holroyd, Nancy; Hahnel, Steffen; Quack, Thomas; Berriman, Matthew; Grevelding, Christoph G

    2016-01-01

    As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects. PMID:27499125

  6. Sex and stress steroids in adolescence: Gonadal regulation of the hypothalamic-pituitary-adrenal axis in the rat.

    PubMed

    Green, Matthew R; McCormick, Cheryl M

    2016-08-01

    This review provides an overview of the current understanding of the role of the hypothalamic-pituitary-gonadal (HPG) axis in regulating the hypothalamic-pituitary-adrenal (HPA) axis response to stressors. HPA function is influenced by both organizational (programming) and activational effects of gonadal hormones. Typically, in adult rats, estradiol increases and androgens decrease the HPA response to stressors, thereby contributing to sex differences in HPA function, and sensitivity of the HPA axis to gonadal steroids is in part determined by exposure to these hormones in early development. Although developmental differences in HPA function are well characterized, the extent to which gonadal steroids contribute to age differences in HPA function is not well understood. Deficits in the understanding of the relationships between the HPA and HPG axes are greatest for the adolescent period of development. The critical outstanding questions are, when do gonadal hormones begin to regulate HPA function in adolescence, and what mechanisms precipitate change in sensitivity of the HPA axis to the HPG axis at this stage of life.

  7. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay

    PubMed Central

    Lu, Zhigang; Sessler, Florian; Holroyd, Nancy; Hahnel, Steffen; Quack, Thomas; Berriman, Matthew; Grevelding, Christoph G.

    2016-01-01

    As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects. PMID:27499125

  8. Sex and stress steroids in adolescence: Gonadal regulation of the hypothalamic-pituitary-adrenal axis in the rat.

    PubMed

    Green, Matthew R; McCormick, Cheryl M

    2016-08-01

    This review provides an overview of the current understanding of the role of the hypothalamic-pituitary-gonadal (HPG) axis in regulating the hypothalamic-pituitary-adrenal (HPA) axis response to stressors. HPA function is influenced by both organizational (programming) and activational effects of gonadal hormones. Typically, in adult rats, estradiol increases and androgens decrease the HPA response to stressors, thereby contributing to sex differences in HPA function, and sensitivity of the HPA axis to gonadal steroids is in part determined by exposure to these hormones in early development. Although developmental differences in HPA function are well characterized, the extent to which gonadal steroids contribute to age differences in HPA function is not well understood. Deficits in the understanding of the relationships between the HPA and HPG axes are greatest for the adolescent period of development. The critical outstanding questions are, when do gonadal hormones begin to regulate HPA function in adolescence, and what mechanisms precipitate change in sensitivity of the HPA axis to the HPG axis at this stage of life. PMID:26851306

  9. The effect of epilepsy and antiepileptic drugs on sexual, reproductive and gonadal health of adults with epilepsy.

    PubMed

    Hamed, Sherifa A

    2016-06-01

    Epilepsy is a common chronic medical illness. Hyposexuality is the most frequent abnormality in men and women with epilepsy. In men with epilepsy, hypoandrogenimia, hypogonadism and sperm abnormalities are common. Testicular atrophy was also infrequently reported. In women with epilepsy, hyperandrogenism, polycystic ovaries (PCOs) and PCO syndrome are frequent. Decreased serum free testosterone, dehydroepiandrosterone levels, free androgen index and free testosterone/leutinizing hormone (LH) ratio and increased sex hormone binding globulin, estradiol, prolactin, LH, follicle stimulating hormone (FSH) levels and LH/FSH ratio are common with epilepsy. Disturbance of central and/or peripheral control of hypothalamic-pituitary-gonadal axis and alteration of central neurotrasmitters (GABA, glutamate and serotonin) by epileptic discharges or antiepileptic drugs (AEDs), direct gonadal toxicity by AEDs and pcyshicatric/psychosocial factors are all incriminated in sexual, reproductive and gonadal abnormalities associated with epilepsy. Patients may benefit from multidisplinary evaluation, tight seizure control, change the AED, androgen therapy, genital vasodilators, L-carnitine supplementation and psychotherapy.

  10. Identification of gonadal soma-derived factor involvement in Monopterus albus (protogynous rice field eel) sex change.

    PubMed

    Zhu, Yefei; Wang, Chunlei; Chen, Xiaowu; Guan, Guijun

    2016-07-01

    We studied molecular events and potential mechanisms underlying the process of female-to-male sex transformation in the rice field eel (Monopterus albus), a protogynous hermaphrodite fish in which the gonad is initially a female ovary and transforms into male testes. We cloned and identified a novel gonadal soma derived factor (GSDF), which encodes a member of the transforming growth factor-beta superfamily. gsdf expression was measured in gonads of female, intersex and male with reverse transcription-PCR and gsdf's role in sex transformation was studied with qPCR, histological analysis and dual-color in situ hybridization assays and compared to other sex-related genes. gsdf was correlated to Sertoli cell differentiation, indicating involvement in testicular differentiation and sex transformation from female to male in this species. A unique expression pattern reveals a potential role of gsdf essential for the sex transformation of rice field eels. PMID:27230579

  11. Gonadal steroidogenesis in vitro from juvenile alligators obtained from contaminated or control lakes.

    PubMed Central

    Guillette, L J; Gross, T S; Gross, D A; Rooney, A A; Percival, H F

    1995-01-01

    The ubiquitous distribution of many contaminants and the nonlethal, multigenerational effects of such contaminants on reproductive, endocrine, and immune systems have led to concerns that wildlife worldwide are affected. Although the causal agents and effects are known for some species, the underlying physiological mechanisms associated with contaminant-induced reproductive modifications are still poorly understood and require extensive research. We describe a study examining the steroidogenic activity of gonads removed from juvenile alligators (Alligator mississippiensis) obtained from contaminated or control lakes in central Florida. Synthesis of estradiol-17 beta (E2) was significantly different when ovaries from the contaminated and control lakes were compared in vitro. Additionally, testes from males obtained from the contaminated lake. Lake Apopka, synthesized significantly higher concentrations of E2 when compared to testes obtained from control males. In contrast, testosterone (T) synthesis from all testes examined in this study displayed a normal pattern and produced concentrations greater than that observed from ovaries obtained from either lake. Interestingly, the pattern of gonadal steroidogenesis differs from previously reported plasma concentrations of these hormones obtained from the same individuals. We suggest that the differences between the in vivo and in vitro patterns are due to modifications in the hepatic degradation of plasma sex steroid hormones. PMID:7556021

  12. Early segregation of germ and somatic lineages during gonadal regeneration in the annelid Enchytraeus japonensis.

    PubMed

    Tadokoro, Ryosuke; Sugio, Mutsumi; Kutsuna, Junko; Tochinai, Shin; Takahashi, Yoshiko

    2006-05-23

    Although regeneration studies are useful for understanding how organs renew, little information is available about regeneration of reproductive organs and germ cells. We here describe the behavior of germ-cell precursors during regeneration of the oligochaete annelid worm Enchytraeus japonensis, which has the remarkable feature of undergoing asexual (by fission) and sexual reproduction . We first found that the gonad can regenerate from any body fragment yielded by fission during asexual reproduction. We then examined behavior of germ-cell lineage during this regenerative process, by using a homolog of the Piwi gene (Ej-piwi) as a marker. We found that in asexually growing animals, specialized cells expressing Ej-piwi are distributed widely in the body as single cells. These cells seem to serve as a reservoir of germ-cell precursors because during asexual propagation these cells migrate into the regenerating tissue, where they ultimately settle in the prospective gonads, and give rise to germ cells upon sexualization. These cells are distinct from the neoblasts, thought to be stem cells in other animals. This is the first report to directly show that the germ and somatic lineages are segregated in asexually growing animals and behave differently during regeneration.

  13. Melatonin and pituitary-gonadal function in disorders of eating behavior.

    PubMed

    Ferrari, E; Foppa, S; Bossolo, P A; Comis, S; Esposti, G; Licini, V; Fraschini, F; Brambilla, F

    1989-01-01

    In order to study the possible relationships between melatonin secretion and pituitary-gonadal function, the circadian rhythm of plasma melatonin, the basal levels of estradiol-17beta and testosterone and the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) response to luteinizing hormone-releasing hormone (LH-RH) stimulation were evaluated in normally cycling healthy women and in two groups of women with menstrual dysfunctions related to eating disorders (19 patients with anorexia nervosa and 16 with primary obesity). The circadian rhythm of plasma melatonin reached statistical significance in anorectic patients but not in obese patients. The mean 24 h melatonin level was significantly higher in anorectic than in obese patients and in control subjects. However, both groups of patients shared some abnormalities of melatonin circadian pattern, such as increased ratio between day and night melatonin levels, abnormal secretory peaks during the light hours and great interindividual variability for timing, amplitude, and duration of melatonin nocturnal peak. A selective impairment of LH secretion was observed in both anorectic and obese patients. By considering together the two groups of patients and controls, a linear inverse correlation between the circadian mesor of plasma melatonin and the basal and LH-RH stimulated LH levels was found. The persistence of a certain melatonin secretion during the light hours in both anorectic and obese patients could play an inhibitory role on the pituitary gonadal function in these subjects.

  14. Morphometics and Gonadal Development of the Hagfish Eptatretus cirrhatus in New Zealand

    PubMed Central

    Martini, Frederic H.; Beulig, Alfred

    2013-01-01

    Hagfishes have been the target of commercial fisheries in many areas of the world, with the catch processed for leather and for human consumption. A fishery has been operating in New Zealand waters for the last six years, harvesting the bearded hagfish, Eptatretus cirrhatus. The fishery has thus far been unregulated. Based on samples collected dockside over a two-year period, this report expands the morphometric database for this species, provides information on the size and weight of the harvested animals, determines the sizes at the onset of gonadal development and the minimum sizes at sexual maturation for males and females, and indicates that E. cirrhatus, like most other hagfish species, has no specific breeding season. Although females appear in the population at smaller sizes, the sex ratio for mature animals is 1:1 and the sizes of the largest males and females are comparable. The changes observed in sex ratio as a function of TL suggest differences in the timing and rates of gonadal development in females versus males rather than protogyny. Based on the size of the eggs, the number of eggs per female, the proportion of the population that contains large eggs, and the number of postovulatory females, it is clear that E. cirrhatus, like other hagfish species, are potentially vulnerable to overexploitation. PMID:24250811

  15. Transgenerational epigenetic imprinting of the male germline by endocrine disruptor exposure during gonadal sex determination.

    PubMed

    Chang, Hung-Shu; Anway, Matthew D; Rekow, Stephen S; Skinner, Michael K

    2006-12-01

    Embryonic exposure to the endocrine disruptor vinclozolin at the time of gonadal sex determination was previously found to promote transgenerational disease states. The actions of vinclozolin appear to be due to epigenetic alterations in the male germline that are transmitted to subsequent generations. Analysis of the transgenerational epigenetic effects on the male germline (i.e. sperm) identified 25 candidate DNA sequences with altered methylation patterns in the vinclozolin generation sperm. These sequences were identified and mapped to specific genes and noncoding DNA regions. Bisulfite sequencing was used to confirm the altered methylation pattern of 15 of the candidate DNA sequences. Alterations in the epigenetic pattern (i.e. methylation) of these genes/DNA sequences were found in the F2 and F3 generation germline. Therefore, the reprogramming of the male germline involves the induction of new imprinted-like genes/DNA sequences that acquire an apparent permanent DNA methylation pattern that is passed at least through the paternal allele. The expression pattern of several of the genes during embryonic development were found to be altered in the vinclozolin F1 and F2 generation testis. A number of the imprinted-like genes/DNA sequences identified are associated with epigenetic linked diseases. In summary, an endocrine disruptor exposure during embryonic gonadal sex determination was found to promote an alteration in the epigenetic (i.e. induction of imprinted-like genes/DNA sequences) programming of the male germline, and this is associated with the development of transgenerational disease states.

  16. Mutations of gonadotropins and gonadotropin receptors: elucidating the physiology and pathophysiology of pituitary-gonadal function.

    PubMed

    Themmen APN; Huhtaniemi, I T

    2000-10-01

    The recent unraveling of structures of genes for the gonadotropin subunits and gonadotropin receptors has provided reproductive endocrinologists with new tools to study normal and pathological functions of the hypothalamic-pituitary-gonadal axis. Rare inactivating mutations that produce distinctive phenotypes of isolated LH or FSH deficiency have been discovered in gonadotropin subunit genes. In addition, there is a common polymorphism in the LHbeta subunit gene with possible clinical significance as a contributing factor to pathologies of LH-dependent gonadal functions. Both activating and inactivating mutations have been detected in the gonadotropin receptor genes, a larger number in the LH receptor gene, but so far only a few in the gene for the FSH receptor. These mutations corroborate and extend our knowledge of clinical consequences of gonadotropin resistance and inappropriate gonadotropin action. The information obtained from human mutations has been complemented by animal models with disrupted or inappropriately activated gonadotropin ligand or receptor genes. These clinical and experimental genetic disease models form a powerful tool for exploring the physiology and pathophysiology of gonadotropin function and provide an excellent example of the power of molecular biological approaches in the study of pathogenesis of diseases.

  17. Sex difference in irritable bowel syndrome: do gonadal hormones play a role?

    PubMed

    Mulak, Agata; Taché, Yvette

    2010-01-01

    Sex and gender effects in irritable bowel syndrome (IBS) have been reported in epidemiological, physiological, and clinical treatment studies. The potential role of gonadal hormones is discussed based on the female predominance in IBS and the correlation between IBS symptoms and hormonal status. Several different models have been proposed to examine the role of sex hormones in gastrointestinal (GI) function, including changes in GI symptoms during the menstrual cycle and differences in symptom expression in pre- and post-menopausal women as well as changes during pregnancy, hormonal treatment, or after ovariectomy. Gonadal hormones, in particular estrogens, can significantly modulate various clinical manifestations of IBS, including alterations in GI motility and visceral hypersensitivity. Additionally, sex differences in the stress response of the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system are considered to be contributing factors in the pathogenesis of functional bowel disorders. The modulatory effects of estrogens on visceral pain may result from interactions with numerous neurotransmitters at different levels of the brain-gut axis, with a pivotal role of estrogens' interactions with the serotonin and corticotropin-releasing factor (CRF) signaling systems. Estrogens can also modulate neuroimmune interactions triggered by stress via the brain-gut axis. Sex differences in the biological actions, pharmacokinetics, and treatment efficacy of serotonergic medications clearly suggest sex differences in pain pathways that have to be taken into consideration in therapeutic interventions.

  18. The hypothalamic-pituitary-adrenal and gonadal axes in rheumatoid arthritis.

    PubMed

    Cutolo, M; Villaggio, B; Foppiani, L; Briata, M; Sulli, A; Pizzorni, C; Faelli, F; Prete, C; Felli, L; Seriolo, B; Giusti, M

    2000-01-01

    The hypothalamic-pituitary-adrenal (HPA) and the hypothalamic-pituitary-gonadal (HPG) axes involvement or response to immune activation seems crucial for the control of excessive inflammatory and immune conditions such as autoimmune rheumatic diseases, including rheumatoid arthritis (RA). However, female patients seem to depend more on the HPA axis, whereas male patients seem to depend more on the HPG axis. In particular, hypoandrogenism may play a pathogenetic role in male RA patients because adrenal and gonadal androgens, both products of the HPA and HPG axes, are considered natural immunosuppressors. A significantly altered steroidogenesis of adrenal androgens (i.e., dehydroepiandrosterone sulfate, DHEAS and DHEA) in nonglucocorticoid-treated premenopausal RA patients has been described. The menopausal peak of RA suggests that estrogens and/or progesterone deficiency also play a role in the disease, and many data indicate that estrogens suppress cellular immunity, but stimulate humoral immunity (i.e., deficiency promotes cellular Th1-type immunity). A range of physical and psychosocial stressors are also implicated in the activation of the HPA axis and related HPG changes. Chronic and acute stressors appear to have different actions on immune mechanisms with experimental and human studies indicating that acute severe stressors may be even immunosuppressive, while chronic stress may enhance immune responses. The interactions between the immunological and neuroendocrine circuits is the subject of active and extensive ongoing research and might in the near future offer highly promising strategies for hormone-replacement therapies in RA.

  19. Enhanced activity of the pituitary-gonadal axis in premature human infants.

    PubMed

    Tapanainen, J; Koivisto, M; Vihko, R; Huhtaniemi, I

    1981-02-01

    The postnatal pituitary-gonadal function of fullterm and premature boys and girls (mean gestational age, 40 and 32 weeks, respectively) was studied by measurements of serum FSH, LH, PRL, and testosterone (T) between 0-25 weeks of postnatal age. During the first 10 postnatal weeks, serum FSH in premature girls reached 10-20 times higher levels than in fullterm girls (mean at 1-5 weeks, 63 and 3.9 mIU/ml, respectively; P < 1.001). During the same time, serum LH levels were 3-4 times higher in premature (12-17 mIU/ml) than in fullterm girls (3.8-4.7 mIU/ml; P < 0.01). In contrast, no difference in serum gonadotropin levels were observed between premature and fullterm boys. Serum T in premature boys (mean, 2.95 ng/ml) reached a significantly higher level (P < 0.01) than in fullterm boys (1.45 ng/ml) from 11-15 weeks of age. The results emphasize the importance of the last weeks of gestation for the functional maturation of the fetal hypothalamic-pituitary-gonadal axis. Interruption of this maturational process by premature birth results in enhanced pituitary gonadotropin production in girls and increased testicular T production in boys.

  20. Endopeptidase-24.15 in rat hypothalamic/pituitary/gonadal axis.

    PubMed

    Pierotti, A R; Lasdun, A; Ayala, J M; Roberts, J L; Molineaux, C J

    1991-04-01

    Endopeptidase-24.15 (E.C. 3.4.24.15; EP-24.15) cleaves several substrates found in the hypothalamic/pituitary/gonadal axis, including gonadotropin-releasing hormone (GnRH) and the opioid peptides of the dynorphin family. We have examined the activity of EP-24.15 in these tissues as a function of maturation, of the estrous cycle, and in response to ovariectomy and estrogen replacement. A developmental regulation of EP-24.15-specific activity is apparent in anterior pituitary, in hypothalamus, and in the gonads. EP-24.15 is increased in the preoptic area and is decreased in the anterior pituitary in both male and female rats prior to puberty. The specific activity of EP-24.15 was increased following ovariectomy in the anterior pituitary and within medial and lateral preoptic nuclei. Testicular specific activity of EP-24.15 increased with age in a linear fashion, while ovarian EP-24.15 activity increased immediately prior to puberty, but returned to prepubertal levels by 65 days of age. The relevance of EP-24.15 to the metabolism of specific peptides is discussed.

  1. Increased levels of adrenocortical and gonadal hormones in mild to moderate Alzheimer's disease.

    PubMed

    Rasmuson, Sigbritt; Näsman, Birgitta; Carlström, Kjell; Olsson, Tommy

    2002-01-01

    Hormonal changes during normal aging include decreasing levels of gonadal hormones and adrenal androgens. These hormones influence multiple nervous functions, including cognition and mood. Related to this, abnormalities at several levels of the hypothalamic-pituitary-adrenal axis (HPA) have been reported in patients with Alzheimer's disease (AD). We studied steroid hormones in 33 patients with mild to moderate AD (12 men; 21 women, 76.4 +/- 7.8 years) and 22 healthy elderly controls (10 men; 12 women, 75.4 +/- 7.5 years old, respectively). Basal levels of serum cortisol, dehydroepiandrosterone (DHEA) and androstenedione were significantly increased in AD patients. Women with AD had significantly higher levels of DHEA and androstenedione. Serum estradiol levels were non-significantly increased in women with AD. After adjustment for age and BMI women with AD had significantly increased levels of androstenedione and DHEA. Increased gonadal hormone levels in mild to moderate AD may reflect an increased secretion, and/or alterations in metabolism of these hormones. This may influence the symptomatology and progression of the disease.

  2. Sexual Precocity--Genetic Bases of Central Precocious Puberty and Autonomous Gonadal Activation.

    PubMed

    Macedo, Delanie Bulcão; Silveira, Letícia Ferreira Gontijo; Bessa, Danielle Souza; Brito, Vinicius Nahime; Latronico, Ana Claudia

    2016-01-01

    Precocious puberty has been classically defined as the onset of sexual secondary characteristics in girls younger than 8 years and in boys younger than 9 years. The discovery of potential factors which trigger human puberty is one of the central mysteries of reproductive biology. Several approaches, including mutational analysis of candidate genes, large-scale genome-wide association studies, and (more recently) whole-exome sequencing, have been performed in attempt to identify novel genetic factors that modulate the human hypothalamic-pituitary-gonadal axis, resulting in premature sexual development. In the last two decades, it has been well established that autonomous gonadal activation can be caused by somatic (GNAS) or germline (LHCGR)-activating mutations of genes that encode essential elements for signal transduction of G protein-coupled receptors, resulting in peripheral precocious puberty in McCune-Albright syndrome and testotoxicosis, respectively. More recently, dominant activating and inactivating mutations of excitatory (KISS1/KISS1R) and inhibitory (MKRN3) modulators of gonadotropin-releasing hormone secretion, respectively, were associated with central precocious puberty phenotype. Indeed, loss-of-function mutations of MKRN3, a maternal imprinted gene located at chromosome 15q, currently represent a frequent cause of central precocious puberty diagnosed in families from distinct geographic origins. Here, we review the known genetic defects in central and peripheral precocious puberty.

  3. Molecular aspects of the ontogeny of the pituitary-gonadal axis.

    PubMed

    Huhtaniemi, I

    1995-01-01

    The endocrine function of the mammalian pituitary-gonadal axis begins in utero. This is important particularly for the ontogeny and function of the male reproductive organs, the induction of which is critically dependent on the two fetal testicular hormones, testosterone and anti-müllerian hormone. In contrast, ovarian endocrine activity begins only after birth. The earliest phases of testicular hormone production are probably under autocrine or paracrine regulation, but the dependence on gonadotrophins starts in fetal life. During maturation of the hypothalamic-pituitary-testicular axis, the target organs acquire their responsiveness (viz receptors) before the onset of secretion of the tropic hormonal stimulus. The last link to develop is the feedback regulation, and the whole axis is functional in the developing male rat during the last days of gestation. Although gonadotrophin secretion starts in both sexes simultaneously, the fetal ovary is endocrinologically quiescent--its gonadotrophin responsiveness and endocrine activity begin only after birth. The fetal and postnatal periods of testicular activity have crucial effects on male sexual differentiation, whereas in the female, early sexual development occurs autonomously without influence of ovarian function. The purpose of this review is to elucidate some of the recent findings on the molecular mechanisms involved in the perinatal maturation of the rat hypothalamic-pituitary-gonadal axis.

  4. Active hypothalamic-pituitary-gonadal axis in an infant with X-linked adrenal hypoplasia congenita.

    PubMed

    Takahashi, T; Shoji, Y; Shoji, Y; Haraguchi, N; Takahashi, I; Takada, G

    1997-03-01

    To evaluate the hypothalamic-pituitary-gonadal axis in an infant with adrenal hypoplasia congenita, we measured the serum levels of testosterone and performed a luteinizing hormone-releasing hormone stimulation test. The diagnosis was made because of the presence of a mutation, A300V, in the DAX-1 gene. The results demonstrated an active hypothalamic-pituitary-gonadal axis, with adult-level testosterone of 266 ng/dl on day 0, and maintenance of testosterone concentration in the 100 to 250 ng/dl range for 140 days as expected. The luteinizing hormone-releasing hormone lest was compatible with an active pituitary gland with a luteinizing hormone peak of 13.1 IU/L and a follicle-stimulating hormone of 5.0 IU/L We conclude that the DAX-1 mutation does allow a normal reproductive axis at birth. We speculate that sometime between infancy and puberty this mutation in the DAX-1 gene leads to an inability to activate the reproductive axis from its childhood suppression; thus puberty will not develop in this infant.

  5. Crossover of the hypothalamic pituitary-adrenal/interrenal, -thyroid, and -gonadal axes in testicular development.

    PubMed

    Castañeda Cortés, Diana C; Langlois, Valerie S; Fernandino, Juan I

    2014-01-01

    Besides the well-known function of thyroid hormones (THs) for regulating metabolism, it has recently been discovered that THs are also involved in testicular development in mammalian and non-mammalian species. THs, in combination with follicle stimulating hormone, lead to androgen synthesis in Danio rerio, which results in the onset of spermatogenesis in the testis, potentially relating the hypothalamic-pituitary-thyroid (HPT) gland to the hypothalamic-pituitary-gonadal (HPG) axes. Furthermore, studies in non-mammalian species have suggested that by stimulating the thyroid-stimulating hormone (TSH), THs can be induced by corticotropin-releasing hormone. This suggests that the hypothalamic-pituitary-adrenal/interrenal gland (HPA) axis might influence the HPT axis. Additionally, it was shown that hormones pertaining to both HPT and HPA could also influence the HPG endocrine axis. For example, high levels of androgens were observed in the testis in Odonthestes bonariensis during a period of stress-induced sex-determination, which suggests that stress hormones influence the gonadal fate toward masculinization. Thus, this review highlights the hormonal interactions observed between the HPT, HPA, and HPG axes using a comparative approach in order to better understand how these endocrine systems could interact with each other to influence the development of testes.

  6. Patterns of hypothalamic-pituitary-gonadal dysfunction in men with liver disease due to differing etiologies.

    PubMed

    van Thiel, D H; Gavaler, J S; Spero, J A; Egler, K M; Wright, C; Sanghvi, A T; Hasiba, U; Lewis, J H

    1981-01-01

    The hypothalamic-pituitary-gonadal axis was evaluated in two groups of age-matched men with documented biochemical and histologic liver disease and compared to that of age-matched normal controls. Basal testosterone levels (p less than 0.05), spermatozoa concentrations (p less than 0.01), and seminal plasma volume (p less than 0.01) were reduced in the alcoholics studied with liver disease, but not the hemophiliacs with liver disease when compared to the normal controls. No difference in estradiol levels was noted between groups. Basal follicle-stimulating hormone and luteinizing hormone (LH) concentrations were increased (both p less than 0.01) in the alcoholics while only LH concentrations were increased (p less than 0.01) in the hemophiliacs compared to the normal controls. Gonadotropins (follicle-stimulating hormone and LH) and testosterone responses to clomiphene and to luteinizing hormone-releasing factor (LH only) in the alcoholic population studied, further distinguished the alcoholics from the hemophiliacs and the normal controls. The basal levels of the other anterior pituitary hormones (growth hormone and thyroid-stimulating hormone) as well as their provocative responses to thyrotropin-releasing hormone also distinguished the alcoholics from the hemophiliac population. Based upon these results, we propose that factors other than the liver disease per se are responsible for the disturbances of hypothalamic-pituitary-gonadal function observed in men with biochemically as well as histologically advanced stable liver disease.

  7. Exogenous Testosterone, Aging, and Changes in Behavioral Response of Gonadally Intact Male Mice

    PubMed Central

    Onaolapo, Olakunle J.; Onaolapo, Adejoke Y.; Omololu, Tope A.; Oludimu, Adedunke T.; Segun-Busari, Toluwalase; Omoleke, Taofeeq

    2016-01-01

    This study tested the hypothesis that aging significantly affects the influence of exogenous testosterone on neurobehavior in gonadally intact male mice. Groups of prepubertal and aged male mice received daily vehicle or testosterone propionate (TP; 2.5 or 5.0 mg/kg intraperitoneal [i.p.]) for 21 days. Behaviors were assessed on days 1 and 21. Weight gain was significant in prepubertal mice. Locomotion and rearing increased in prepubertal mice after first dose and decreased after last dose of TP. Rearing was suppressed in aged mice throughout. Suppression of grooming occurred in both age groups at day 21. Significant increase in working memory in both age groups was seen in the radial-arm maze (at specific doses) and in prepubertal mice in the Y-maze. Elevated plus maze test showed mixed anxiolytic/anxiogenic effects. Aged mice had higher serum testosterone. In conclusion, age is an important determinant for the influence of exogenous testosterone on behavior in gonadally intact male mice. PMID:27158222

  8. Foxl2 and Its Relatives Are Evolutionary Conserved Players in Gonadal Sex Differentiation.

    PubMed

    Bertho, Sylvain; Pasquier, Jeremy; Pan, Qiaowei; Le Trionnaire, Gaël; Bobe, Julien; Postlethwait, John H; Pailhoux, Eric; Schartl, Manfred; Herpin, Amaury; Guiguen, Yann

    2016-01-01

    Foxl2 is a member of the large family of Forkhead Box (Fox) domain transcription factors. It emerged during the last 15 years as a key player in ovarian differentiation and oogenesis in vertebrates and especially mammals. This review focuses on Foxl2 genes in light of recent findings on their evolution, expression, and implication in sex differentiation in animals in general. Homologs of Foxl2 and its paralog Foxl3 are found in all metazoans, but their gene evolution is complex, with multiple gains and losses following successive whole genome duplication events in vertebrates. This review aims to decipher the evolutionary forces that drove Foxl2/3 gene specialization through sub- and neo-functionalization during evolution. Expression data in metazoans suggests that Foxl2/3 progressively acquired a role in both somatic and germ cell gonad differentiation and that a certain degree of sub-functionalization occurred after its duplication in vertebrates. This generated a scenario where Foxl2 is predominantly expressed in ovarian somatic cells and Foxl3 in male germ cells. To support this hypothesis, we provide original results showing that in the pea aphid (insects) foxl2/3 is predominantly expressed in sexual females and showing that in bovine ovaries FOXL2 is specifically expressed in granulosa cells. Overall, current results suggest that Foxl2 and Foxl3 are evolutionarily conserved players involved in somatic and germinal differentiation of gonadal sex. PMID:27441599

  9. Activation of the hypothalamic-pituitary-gonadal axis in infancy: minipuberty.

    PubMed

    Kuiri-Hänninen, Tanja; Sankilampi, Ulla; Dunkel, Leo

    2014-01-01

    The hypothalamic-pituitary-gonadal (HPG) axis is active in the midgestational foetus but silenced towards term because of the negative feedback effects mediated by the placental hormones. This restraint is removed at birth, leading to reactivation of the axis and an increase in gonadotrophin levels. Gonadotrophin levels are high during the first 3 months of life but decrease towards the age of 6 months except for FSH levels in girls that remain elevated until 3-4 years of age. After this, the HPG axis remains quiescent until puberty. The postnatal gonadotrophin surge results in gonadal activation in both sexes. In boys, testosterone levels rise to a peak at 1-3 months of age and then decline following LH levels. Postnatal HPG axis activation is associated with penile and testicular growth and therefore considered important for the development of male genitalia. In girls, elevated gonadotrophin levels result in the maturation of ovarian follicles and in an increase in oestradiol levels. Biological significance and possible long-term consequences of this minipuberty remain elusive, as do the mechanisms that silence the HPG axis until puberty. However, the first months of life provide a 'window of opportunity' for functional studies of the HPG axis prior to pubertal development.

  10. A mutation in the nucleoporin-107 gene causes XX gonadal dysgenesis

    PubMed Central

    Weinberg-Shukron, Ariella; Renbaum, Paul; Kalifa, Rachel; Zeligson, Sharon; Ben-Neriah, Ziva; Dreifuss, Amatzia; Abu-Rayyan, Amal; Maatuk, Noa; Fardian, Nilly; Rekler, Dina; Kanaan, Moien; Samson, Abraham O.; Levy-Lahad, Ephrat; Gerlitz, Offer; Zangen, David

    2015-01-01

    Ovarian development and maintenance are poorly understood; however, diseases that affect these processes can offer insights into the underlying mechanisms. XX female gonadal dysgenesis (XX-GD) is a rare, genetically heterogeneous disorder that is characterized by underdeveloped, dysfunctional ovaries, with subsequent lack of spontaneous pubertal development, primary amenorrhea, uterine hypoplasia, and hypergonadotropic hypogonadism. Here, we report an extended consanguineous family of Palestinian origin, in which 4 females exhibited XX-GD. Using homozygosity mapping and whole-exome sequencing, we identified a recessive missense mutation in nucleoporin-107 (NUP107, c.1339G>A, p.D447N). This mutation segregated with the XX-GD phenotype and was not present in available databases or in 150 healthy ethnically matched controls. NUP107 is a component of the nuclear pore complex, and the NUP107-associated protein SEH1 is required for oogenesis in Drosophila. In Drosophila, Nup107 knockdown in somatic gonadal cells resulted in female sterility, whereas males were fully fertile. Transgenic rescue of Drosophila females bearing the Nup107D364N mutation, which corresponds to the human NUP107 (p.D447N), resulted in almost complete sterility, with a marked reduction in progeny, morphologically aberrant eggshells, and disintegrating egg chambers, indicating defective oogenesis. These results indicate a pivotal role for NUP107 in ovarian development and suggest that nucleoporin defects may play a role in milder and more common conditions such as premature ovarian failure. PMID:26485283

  11. A mutation in the nucleoporin-107 gene causes XX gonadal dysgenesis.

    PubMed

    Weinberg-Shukron, Ariella; Renbaum, Paul; Kalifa, Rachel; Zeligson, Sharon; Ben-Neriah, Ziva; Dreifuss, Amatzia; Abu-Rayyan, Amal; Maatuk, Noa; Fardian, Nilly; Rekler, Dina; Kanaan, Moien; Samson, Abraham O; Levy-Lahad, Ephrat; Gerlitz, Offer; Zangen, David

    2015-11-01

    Ovarian development and maintenance are poorly understood; however, diseases that affect these processes can offer insights into the underlying mechanisms. XX female gonadal dysgenesis (XX-GD) is a rare, genetically heterogeneous disorder that is characterized by underdeveloped, dysfunctional ovaries, with subsequent lack of spontaneous pubertal development, primary amenorrhea, uterine hypoplasia, and hypergonadotropic hypogonadism. Here, we report an extended consanguineous family of Palestinian origin, in which 4 females exhibited XX-GD. Using homozygosity mapping and whole-exome sequencing, we identified a recessive missense mutation in nucleoporin-107 (NUP107, c.1339G>A, p.D447N). This mutation segregated with the XX-GD phenotype and was not present in available databases or in 150 healthy ethnically matched controls. NUP107 is a component of the nuclear pore complex, and the NUP107-associated protein SEH1 is required for oogenesis in Drosophila. In Drosophila, Nup107 knockdown in somatic gonadal cells resulted in female sterility, whereas males were fully fertile. Transgenic rescue of Drosophila females bearing the Nup107D364N mutation, which corresponds to the human NUP107 (p.D447N), resulted in almost complete sterility, with a marked reduction in progeny, morphologically aberrant eggshells, and disintegrating egg chambers, indicating defective oogenesis. These results indicate a pivotal role for NUP107 in ovarian development and suggest that nucleoporin defects may play a role in milder and more common conditions such as premature ovarian failure.

  12. Gonadal mosaicism in ARID1B gene causes intellectual disability and dysmorphic features in three siblings.

    PubMed

    Ben-Salem, Salma; Sobreira, Nara; Akawi, Nadia A; Al-Shamsi, Aisha M; John, Anne; Pramathan, Thachillath; Valle, David; Ali, Bassam R; Al-Gazali, Lihadh

    2016-01-01

    The gene encoding the AT-rich interaction domain-containing protein 1B (ARID1B) has recently been shown to be one of the most frequently mutated genes in patients with intellectual disability (ID). The phenotypic spectrums associated with variants in this gene vary widely ranging for mild to severe non-specific ID to Coffin-Siris syndrome. In this study, we evaluated three children from a consanguineous Emirati family affected with ID and dysmorphic features. Genomic DNA from all affected siblings was analyzed using CGH array and whole-exome sequencing (WES). Based on a recessive mode of inheritance, homozygous or compound heterozygous variants shared among all three affected children could not be identified. However, further analysis revealed a heterozygous variant (c.4318C>T; p.Q1440*) in the three affected children in an autosomal dominant ID causing gene, ARID1B. This variant was absent in peripheral blood samples obtained from both parents and unaffected siblings. Therefore, we propose that the most likely explanation for this situation is that one of the parents is a gonadal mosaic for the variant. To the best of our knowledge, this is the first report of a gonadal mosaicism inheritance of an ARID1B variant leading to familial ID recurrence. PMID:26395437

  13. Gonadal Expression of Foxo1, but Not Foxo3, Is Conserved in Diverse Mammalian Species1

    PubMed Central

    Tarnawa, Edward D.; Baker, Michael D.; Aloisio, Gina M.; Carr, Bruce R.; Castrillon, Diego H.

    2013-01-01

    ABSTRACT The Foxos are key effectors of the PI3K/Akt signaling pathway and regulate diverse physiologic processes. Two of these factors, Foxo1 and Foxo3, serve specific roles in reproduction in the mouse. Foxo3 is required for suppression of primordial follicle activation in females, while Foxo1 regulates spermatogonial stem cell maintenance in males. In the mouse ovary, Foxo1 is highly expressed in somatic cells (but not in oocytes), suggesting an important functional role for Foxo1 in these cells. Given that invertebrate model species such as Caenorhabditis elegans and Drosophila melanogaster harbor a single ancestral Foxo homolog, these observations suggest that gene duplication conferred a selective advantage by permitting the Foxos to adopt distinct roles in oogenesis and spermatogenesis. Our objective was to determine if the remarkably specific expression patterns of Foxo1 and Foxo3 in mouse gonads (and, by inference, Foxo function) are conserved in diverse mammalian species. Western blotting was used to validate isoform-specific antibodies in rodents, companion animals, farm animals, nonhuman primates, and humans. Following validation of each antibody, immunohistochemistry was performed to ascertain Foxo1 and Foxo3 gonadal expression patterns. While Foxo1 expression in spermatogonia and granulosa cells was conserved in each species evaluated, Foxo3 expression in oocytes was not. Our findings suggest that Foxo3 is not uniquely required for primordial follicle maintenance in nonrodent species and that other Foxos, particularly Foxo1, may contribute to oocyte maintenance in a functionally redundant manner. PMID:23486915

  14. Stroke sensitivity in the aged: sex chromosome complement vs. gonadal hormones

    PubMed Central

    McCullough, Louise D.; Mirza, Mehwish A.; Xu, Yan; Bentivegna, Kathryn; Steffens, Eleanor B.; Ritzel, Rodney; Liu, Fudong

    2016-01-01

    Stroke is a sexually dimorphic disease. Elderly women not only have higher stroke incidence than age-matched men, but also have poorer recovery and higher morbidity and mortality after stroke. In older, post-menopausal women, gonadal hormone levels are similar to that of men. This suggests that tissue damage and functional outcomes are influenced by biologic sex (XX vs. XY) rather than the hormonal milieu at older ages. We employed the Four Core Genotype (FCG) mouse model to study the contribution of sex chromosome complement and gonadal hormones to stroke sensitivity in aged mice in which the testis determining gene (Sry) is removed from the Y chromosome, allowing for the generation of XX males and XY females. XXF, XXM, XYF, XYM and XYwt aged mice were subjected to middle cerebral artery occlusion (MCAO). XXF and XXM mice had significantly larger infarct volumes than XYF and XYM cohorts respectively. There was no significant difference in hormone levels among aged FCG mice. XXF/XXM mice also had more robust microglial activation and higher serum levels of pro-inflammatory cytokines than XYF/XYM cohort respectively. We concluded that the sex chromosome complement contributes to ischemic sensitivity in aged animals and leads to sex differences in innate immune responses. PMID:27405096

  15. Circulating gonadal and adrenal steroids in amyotrophic lateral sclerosis: possible markers of susceptibility and outcome.

    PubMed

    Gargiulo-Monachelli, G M; Sivori, M; Meyer, M; Sica, R E P; De Nicola, A F; Gonzalez-Deniselle, M C

    2014-06-01

    Although changes of circulating steroids have been reported in patients with sporadic amyotrophic lateral sclerosis (ALS), a full comparison of the adrenal and gonadal steroid profile between control subjects and ALS patients is lacking. Considering that respiratory failure is the most frequent cause of death in ALS, we looked into whether a relationship emerged between circulating steroids and respiratory parameters. Serum levels of adrenal and gonadal steroids were measured in 52 age- and gender-matched subjects (28 ALS and 24 controls) using radioimmunoassay techniques. We also evaluated respiratory parameters in ALS patients, including forced vital capacity (FVC), maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP). We found increased levels of testosterone in female ALS patients compared to healthy female subjects. Furthermore, control subjects showed a significant decline of testosterone, dehydroepiandrosterone and its sulfate, and a borderline decline of progesterone with increasing age. Instead, testosterone did not decline with increasing age in ALS patients. We also found that the dehydroepiandrosterone sulfate/cortisol ratio was positively associated with FVC, MIP, and MEP. Moreover, ALS patients showing higher testosterone levels and lower progesterone/free testosterone ratio presented a more rapid worsening of the monthly FVC. In conclusion, first our study revealed a differential steroid profile with age and gender in ALS patients relative to controls. Second, we demonstrated an association between some steroids and their ratios with respiratory function and disease progression. Thus, we hypothesize that the endogenous steroid profile could be a marker of susceptibility and prognosis in ALS patients.

  16. Specific involvement of gonadal hormones in the functional maturation of growth hormone releasing hormone (GHRH) neurons.

    PubMed

    Gouty-Colomer, Laurie-Anne; Méry, Pierre-François; Storme, Emilie; Gavois, Elodie; Robinson, Iain C; Guérineau, Nathalie C; Mollard, Patrice; Desarménien, Michel G

    2010-12-01

    Growth hormone (GH) is the key hormone involved in the regulation of growth and metabolism, two functions that are highly modulated during infancy. GH secretion, controlled mainly by GH releasing hormone (GHRH), has a characteristic pattern during postnatal development that results in peaks of blood concentration at birth and puberty. A detailed knowledge of the electrophysiology of the GHRH neurons is necessary to understand the mechanisms regulating postnatal GH secretion. Here, we describe the unique postnatal development of the electrophysiological properties of GHRH neurons and their regulation by gonadal hormones. Using GHRH-eGFP mice, we demonstrate that already at birth, GHRH neurons receive numerous synaptic inputs and fire large and fast action potentials (APs), consistent with effective GH secretion. Concomitant with the GH secretion peak occurring at puberty, these neurons display modifications of synaptic input properties, decrease in AP duration, and increase in a transient voltage-dependant potassium current. Furthermore, the modulation of both the AP duration and voltage-dependent potassium current are specifically controlled by gonadal hormones because gonadectomy prevented the maturation of these active properties and hormonal treatment restored it. Thus, GHRH neurons undergo specific developmental modulations of their electrical properties over the first six postnatal weeks, in accordance with hormonal demand. Our results highlight the importance of the interaction between the somatotrope and gonadotrope axes during the establishment of adapted neuroendocrine functions.

  17. Devicyprin induced gonadal impairment in a freshwater food fish, Channa punctatus (Bloch).

    PubMed

    Srivastava, Rajesh K; Yadav, Kamlesh K; Trivedi, Sunil P

    2008-03-01

    Synthetic pyrethroids are the recent major class of broad spectrum, photostable, organic insecticides used in agricultural, domestic and veterinary applications and now account for more than 30% of global insecticide use. Cypermethrin is metabolized and eliminated significantly more slowly by fish than by mammals or birds, which may explain this compound's high toxicity in fish compared to other organisms. The present communication deals with histoanatomical alterations in the gonads of a local fresh water food fish, Channa punctatus exposed to 0.033 ppm (96 hr LC50 X 1/10) concentration of a synthetic pyrethroid, devicyprin (cypermethrin 25%) in aquatic medium of aged tap water for 15, 30 and 45 days respectively. In testis, exposure dependent histological damage has been observed in terms of vacuolization, condensation of spermatogonic cells, distortion of tubular epithelium, shrinkage of interstitial cells and general inflammatory responses. Longest exposure of 45 days has resulted in peculiar starry-sky appearance of the testicular tissue. Gross histo-anatomy of ovarian tissue reveals epithelial lesions, inflammatory responses, stromal hemorrhage, increased interstitium and shrinkage of yolk vesicles towards periphery These findings are quite suggestive of reproductive impairments leading to delayed gonadal maturity and adversely affecting processes of sperm production and ovulation and thus, the fish production. PMID:18831372

  18. Stroke sensitivity in the aged: sex chromosome complement vs. gonadal hormones.

    PubMed

    McCullough, Louise D; Mirza, Mehwish A; Xu, Yan; Bentivegna, Kathryn; Steffens, Eleanor B; Ritzel, Rodney; Liu, Fudong

    2016-07-01

    Stroke is a sexually dimorphic disease. Elderly women not only have higher stroke incidence than age-matched men, but also have poorer recovery and higher morbidity and mortality after stroke. In older, post-menopausal women, gonadal hormone levels are similar to that of men. This suggests that tissue damage and functional outcomes are influenced by biologic sex (XX vs. XY) rather than the hormonal milieu at older ages. We employed the Four Core Genotype (FCG) mouse model to study the contribution of sex chromosome complement and gonadal hormones to stroke sensitivity in aged mice in which the testis determining gene (Sry) is removed from the Y chromosome, allowing for the generation of XX males and XY females. XXF, XXM, XYF, XYM and XYwt aged mice were subjected to middle cerebral artery occlusion (MCAO). XXF and XXM mice had significantly larger infarct volumes than XYF and XYM cohorts respectively. There was no significant difference in hormone levels among aged FCG mice. XXF/XXM mice also had more robust microglial activation and higher serum levels of pro-inflammatory cytokines than XYF/XYM cohort respectively. We concluded that the sex chromosome complement contributes to ischemic sensitivity in aged animals and leads to sex differences in innate immune responses. PMID:27405096

  19. The Influence of Gonadal Hormones on Neuronal Excitability, Seizures, and Epilepsy in the Female

    PubMed Central

    Scharfman, Helen E.; MacLusky, Neil J.

    2007-01-01

    Summary It is clear from both clinical observations of women, and research in laboratory animals, that gonadal hormones exert a profound influence on neuronal excitability, seizures, and epilepsy. These studies have led to a focus on two of the primary ovarian steroid hormones, estrogen and progesterone, to clarify how gonadal hormones influence seizures in women with epilepsy. The prevailing view is that estrogen is proconvulsant, whereas progesterone is anticonvulsant. However, estrogen and progesterone may not be the only reproductive hormones to consider in evaluating excitability, seizures, or epilepsy in the female. It seems unlikely that estrogen and progesterone would exert single, uniform actions given our current understanding of their complex pharmacological and physiological relationships. Their modulatory effects are likely to depend on endocrine state, relative concentration, metabolism, and many other factors. Despite the challenges these issues raise to future research, some recent advances have helped clarify past confusion in the literature. In addition, testable hypotheses have developed for complex clinical problems such as “catamenial epilepsy.” Clinical and animal research, designed with the relevant endocrinological and neurobiological issues in mind, will help advance this field in the future. PMID:16981857

  20. Gonadal mosaicism in ARID1B gene causes intellectual disability and dysmorphic features in three siblings.

    PubMed

    Ben-Salem, Salma; Sobreira, Nara; Akawi, Nadia A; Al-Shamsi, Aisha M; John, Anne; Pramathan, Thachillath; Valle, David; Ali, Bassam R; Al-Gazali, Lihadh

    2016-01-01

    The gene encoding the AT-rich interaction domain-containing protein 1B (ARID1B) has recently been shown to be one of the most frequently mutated genes in patients with intellectual disability (ID). The phenotypic spectrums associated with variants in this gene vary widely ranging for mild to severe non-specific ID to Coffin-Siris syndrome. In this study, we evaluated three children from a consanguineous Emirati family affected with ID and dysmorphic features. Genomic DNA from all affected siblings was analyzed using CGH array and whole-exome sequencing (WES). Based on a recessive mode of inheritance, homozygous or compound heterozygous variants shared among all three affected children could not be identified. However, further analysis revealed a heterozygous variant (c.4318C>T; p.Q1440*) in the three affected children in an autosomal dominant ID causing gene, ARID1B. This variant was absent in peripheral blood samples obtained from both parents and unaffected siblings. Therefore, we propose that the most likely explanation for this situation is that one of the parents is a gonadal mosaic for the variant. To the best of our knowledge, this is the first report of a gonadal mosaicism inheritance of an ARID1B variant leading to familial ID recurrence.

  1. Expression analysis of Sox9 genes during annual reproductive cycles in gonads and after nanodelivery of LHRH in Clarias batrachus.

    PubMed

    Bhat, Irfan Ahmad; Rather, Mohd Ashraf; Saha, Ratnadeep; Pathakota, Gireesh-Babu; Pavan-Kumar, Annam; Sharma, Rupam

    2016-06-01

    Transcription factor Sox9 plays a crucial role in determining the fate of several cell types and is a primary factor in regulation of gonadal development. Present study reports full-length cDNA sequence of Sox9a gene and partial coding sequence (cds) of Sox9b (two duplicate orthologs of Sox9 gene) from Clarias batrachus. The coding region of Sox9a gene encoded a peptide of 460 amino acids. The partial cds of Sox9b with the length of 558bp was amplified that codes for 186 amino acids. Quantitative Real-time PCR (qRT-PCR) analysis revealed that Sox9a and Sox9b mRNA expression was significantly higher in gonads and brain tissues. Furthermore Sox9a and Sox9b mRNA expression levels were high during preparatory and pre-spawning phases and decreased gradually with onset of spawning and post-spawning phases of reproductive cycles in gonads. Chitosan nanoconjugated sLHRH (CsLHRH) of particle size 133.0nm and zeta potential of 34.3mV were synthesized and evaluated against naked sLHRH (salmon luteinizing hormone-releasing hormone). The entrapment efficiency of CsLHRH was 63%. CsLHRH nanoparticles increased the expression level of Sox9 transcripts in gonads and steroid hormonal levels in blood of male and female. Thus, our findings clearly indicate that Sox9 genes play essential role during seasonal variation of gonads. Besides, the current study reports that sustained release delivery-system will be helpful for proper gonadal development of fish. To the best of our knowledge, till date no study has been reported on nanodelivery of sLHRH and their effect on reproductive gene expression in fish. PMID:27234545

  2. Effect of diets supplemented with different sources of astaxanthin on the gonad of the sea urchin Anthocidaris crassispina.

    PubMed

    Peng, Juan; Yuan, Jian-Ping; Wang, Jiang-Hai

    2012-08-01

    The effect of the microalgae Haematococcus pluvialis and Chorella zofingiensis, and synthetic astaxanthin on the gonad of the sea urchin Anthocidaris crassispina was studied. The basal diet was supplemented with H. pluvialis, C. zofingiensis, or synthetic astaxanthin, at two levels of astaxanthin (approximately 400 mg/kg and 100 mg/kg), to obtain the experimental diets HP1, HP2, CZ1, CZ2, AST1, and AST2, respectively, for two months of feeding experiment. The results showed that the concentrations of astaxanthin in the gonads of the sea urchins fed these experimental diets ranged from 0.15 to 3.01 mg/kg dry gonad weight. The higher astaxanthin levels (>2.90 mg/kg) were found in the gonads of the sea urchins fed the diets HP1 (containing 380 mg/kg of astaxanthins, mostly mono- and diesters) and AST1 (containing 385 mg/kg of synthetic astaxanthin). The lowest astaxanthin level (0.15 mg/kg) was detected in the gonads of the sea urchins fed the diet CZ2 (containing 98 mg/kg of astaxanthins, mostly diesters). Furthermore, the highest canthaxanthin level (7.48 mg/kg) was found in the gonads of the sea urchins fed the diet CZ1 (containing 387 mg/kg of astaxanthins and 142 mg/kg of canthaxanthin), suggesting that astaxanthins, especially astaxanthin esters, might not be assimilated as easily as canthaxanthin by the sea urchins. Our results show that sea urchins fed diets containing astaxanthin pigments show higher incorporation of these known antioxidant constituents, with the resultant seafood products therefore being of potential higher nutritive value.

  3. Histopathological pattern of gonads in cases of sex abnormalities in dogs: An attempt of morphological evaluation involving potential for neoplasia.

    PubMed

    Dzimira, Stanislaw; Nizanski, Wojciech; Ochota, Malgorzata; Madej, Janusz A

    2015-10-01

    Disturbances in sex differentiation (DSD - disorder of sexual development) may result from disturbances in sex chromosomes or a disturbed development of gonads, or from genotypic disturbances. The objective of this article is to describe the histological structure of gonads in dogs showing sexual disturbances and a case of a cancer resembling gonadoblastoma in one of the animals. Among the 10 examined dogs with disturbances of sex development only a single case of a gonadoblastoma was observed. In animals with sex disturbances, similarly to humans, there exists a potential tendency for neoplastic lesions in dysgenetic gonads. As a rule, its frequency in population is confined due to the early procedure of castration of non-breeding dogs. In the present study dogs demonstrated phenotypical traits of bitches with developmental anomalies such as hyperplastic clitoris with vestigial os penis (baculum), or abnormalities in the location and structure of the vulva. The material for the study included canine gonads of various breeds, sampled from phenotypical bitches, aged 7 months to 4 years - patients of the Department of Reproduction and Clinic of Farm Animals, Faculty of Veterinary Medicine, University of Environmental and Life Sciences in Wroclaw (Poland) in years 2006-2013. The organs were surgically removed from the abdomen and sent for histopathological examination for the purpose of determining their histological structure. The 10 examined cases of altered gonads included 6 bilateral cases of testes (60%), 2 cases of bilateral ovotestis (20%), one case of co-manifestation of testis and ovotestis (10%), and a single case of a testis and a neoplastically altered gonad (gonadoblastoma) (10%).

  4. Disruption of apoptosis pathways involved in zebrafish gonad differentiation by 17α-ethinylestradiol and fadrozole exposures.

    PubMed

    Luzio, Ana; Matos, Manuela; Santos, Dércia; Fontaínhas-Fernandes, António A; Monteiro, Sandra M; Coimbra, Ana M

    2016-08-01

    Zebrafish (Danio rerio) sex determination seems to involve genetic factors (GSD) but also environmental factors (ESD), such as endocrine disrupting chemicals (EDCs) that are known to mimic endogenous hormones and disrupt gonad differentiation. Apoptosis has also been proposed to play a crucial role in zebrafish gonad differentiation. Nevertheless, the interactions between EDCs and apoptosis have received little attention. Thus, this study aimed to assess if and which apoptotic pathways are involved in zebrafish gonad differentiation and how EDCs may interfere with this process. With these purposes, zebrafish were exposed to 17α-ethinylestradiol (EE2, 4ng/L) and fadrozole (Fad, 50μg/L) from 2h to 35days post-fertilization (dpf). Afterwards, a gene expression analysis by qRT-PCR and a stereological analysis, based on systematic sampling and protein immunohistochemistry, were performed. The death receptors (FAS; TRADD), anti-apoptotic (BCL-2; MDM2), pro-apoptotic (CASP-2 and -6) and cell proliferation (BIRC5/survivin; JUN) genes and proteins were evaluated. In general, apoptosis was inhibited in females through the involvement of anti-apoptotic pathways, while in males apoptosis seemed to be crucial to the failure of the "juvenile ovary" development and the induction of testes transformation. The JUN protein was shown to be necessary in juvenile ovaries, while the BIRC5 protein seemed to be involved in zebrafish spermatogenesis. Both EDCs, EE2 and Fad, increased the apoptosis stimulus in zebrafish gonad. It was noticed that the few females that were resistant to Fad-induced sex reversal had increased anti-apoptotic factor levels, while males exposed to EE2 showed increased pro-apoptotic genes/proteins and were more advanced in gonad differentiation. Overall, our findings show that apoptosis pathways are involved in zebrafish gonad differentiation and that EDCs can disrupt this process. PMID:27337697

  5. Differential activity of stanniocalcin in male and female fresh water teleost Mastacembelus armatus (Lacepede) during gonadal maturation.

    PubMed

    Verma, Sushant Kumar; Alim, Abdul

    2014-01-01

    The present study was carried out to analyze the differences in the activity of hormone stanniocalcin (STC) between male and female fishes of Mastacembelus armatus during their gonadal cycle. A large variation in nuclear diameter of cells of corpuscles of Stannius (CS) were recorded in relation to testicular cycle as well as ovarian cycle which indicates that the cellular activity varied with different phases of reproductive cycle in both male and female fish. Similar changes in nuclear diameter of CS cells were also observed after 17alpha-methyltestosterone administration in males and 17 β-estradiol administrations in females. A positive correlation was observed between plasma STC levels, gonadosomatic index (GSI) and the sex steroids in both sexes, suggesting that STC has a role in the processes involved in gonadal development. In addition females showed remarkable changes in plasma calcium level during gonadal cycle while no such change for males were observed. In females the plasma calcium level estimated during different phases of reproductive cycle indicates positive correlation between plasma level of calcium and gonad growth. Thus hyperactivity of CS cells was noted in both male and female fishes during gonadal cycle along with the differences in the activity of STC as well. In female it may act as hypocalcemic factor and bring the level of calcium to normal which increases during preparatory and pre spawning phases to fulfill the increased demand of calcium for vitellogenesis. However data of male fishes indicated that plasma STC concentration varied widely during gonadal cycle but showed no consistent relationship to plasma calcium level. PMID:25003342

  6. Sexually dimorphic expression of steroidogenic factor 1 (SF-1) in developing gonads of the American bullfrog, Rana catesbeiana.

    PubMed

    Mayer, Loretta P; Overstreet, Stefanie L; Dyer, Cheryl A; Propper, Catherine R

    2002-06-01

    Genetic sex determination leads to gonadal differentiation and ultimately the differences between the sexes in steroid hormone secretion. Gonadal steroidogenesis is critical for the development of a sexually dimorphic phenotype and adult reproductive function. Control of gonadal development and steroidogenesis is under the regulation, at least in part, of steroidogenic factor-1 (SF-1). We have begun to characterize SF-1 expression in an amphibian to determine the role of this protein in development and reproduction. We have detected a putative SF-1 protein from several tissues in the American bullfrog, Rana catesbeiana, that co-migrates with mouse SF-1 on a Western blot. Our results show that bullfrog SF-1 protein is expressed in steroidogenic and other reproductive tissues in a manner similar to that reported for other species, with high expression in the brain, pituitary, gonad, liver, and interrenal, but little or no expression in non-reproductive tissues such as skin and intestine. Using a quantitative Western blot analysis system, we documented changes in SF-1 protein in the gonads of developing tadpoles. Our results indicate that there is sexually dimorphic expression of SF-1 protein that becomes evident at the time of sexual differentiation of the gonads. In males, the expression of SF-1 decreases following testicular formation and in females the expression increases with the formation of ovaries. This is the first study to investigate changes in SF-1 during development at the protein level. The expression is similar to that reported for changes in SF-1 mRNA expression in chickens and alligators, however, opposite to that seen in mammals and turtles. These results indicate that SF-1 may play a pivotal role in development of the reproductive system in amphibians as it does in other vertebrate groups.

  7. Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio)

    USGS Publications Warehouse

    Sharma, Prakash; Patino, Reynaldo

    2013-01-01

    We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.

  8. Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio).

    PubMed

    Sharma, Prakash; Patiño, Reynaldo

    2013-04-01

    We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.

  9. Morphology, sex steroid level and gene expression analysis in gonadal sex reversal of triploid female (XXX) rainbow trout (Oncorhynchus mykiss).

    PubMed

    Xu, Gefeng; Huang, Tianqing; Jin, Xian; Cui, Cunhe; Li, Depeng; Sun, Cong; Han, Ying; Mu, Zhenbo

    2016-02-01

    In non-mammalian vertebrates, estrogens and expressions of cyp19a1 and foxl2 play critical roles in maintaining ovary differentiation and development, while dmrt1 and sox9 are male-specific genes in testicular differentiation and are highly conserved. In order to deeply understand the morphological change, sex steroids level and molecular mechanism of triploid female gonadal reversal in rainbow trout, we studied the ovary morphology, tendency of estradiol-17β (E2) and testosterone (T) levels and the relative expressions of dmrt1, cyp19a1, sox9 and foxl2 in juvenile and adult fish. Our results demonstrated that the development of triploid female gonads in rainbow trout went through arrested development, oocytes dedifferentiation, ovary reconstruction and sex reversal finally. During early gonadal development (154-334 days post-fertilization), the expressions of foxl2 and cyp19a1 increased linearly, while expressions of dmrt1 and sox9 were extremely suppressed, and E2 level was higher, while T level was lower. During the mid-to-late period of triploid female gonadal development (574-964 days post-fertilization), the expressions of dmrt1 and sox9 remained high and were very close to the quantity of diploid male genes, and T levels were even reaching diploid male plasma concentrations, while expressions of cyp19a1 and foxl2 were decreased, leading to decrease in E2 level. We realized that the development model of rainbow trout triploid female gonads was extremely rare, and the regulatory mechanism was very special. Genes involved in gonadal development and endogenous estrogens are pivotal factors in fish natural sex reversal. PMID:26373423

  10. Sex hormones alter sex ratios in the Indian skipper frog, Euphlyctis cyanophlyctis: Determining sensitive stages for gonadal sex reversal.

    PubMed

    Phuge, S K; Gramapurohit, N P

    2015-09-01

    In amphibians, although genetic factors are involved in sex determination, gonadal sex differentiation can be modified by exogenous steroid hormones suggesting a possible role of sex steroids in regulating the process. We studied the effect of testosterone propionate (TP) and estradiol-17β (E2) on gonadal differentiation and sex ratio at metamorphosis in the Indian skipper frog, Euphlyctis cyanophlyctis with undifferentiated type of gonadal differentiation. A series of experiments were carried out to determine the optimum dose and sensitive stages for gonadal sex reversal. Our results clearly indicate the importance of sex hormones in controlling gonadal differentiation of E. cyanophlyctis. Treatment of tadpoles with 10, 20, 40, and 80μg/L TP throughout larval period resulted in the development of 100% males at metamorphosis at all concentrations. Similarly, treatment of tadpoles with 40μg/L TP during ovarian and testicular differentiation resulted in the development of 90% males, 10% intersexes and 100% males respectively. Treatment of tadpoles with 10, 20, 40, and 80μg/L E2 throughout larval period likewise produced 100% females at all concentrations. Furthermore, exposure to 40μg/L E2 during ovarian and testicular differentiation produced 95% females, 5% intersexes and 91% females, 9% intersexes respectively. Both TP and E2 were also effective in advancing the stages of gonadal development. Present study shows the effectiveness of both T and E2 in inducing complete sex reversal in E. cyanophlyctis. Generally, exposure to E2 increased the larval period resulting in significantly larger females than control group while the larval period of control and TP treated groups was comparable.

  11. Morphology, sex steroid level and gene expression analysis in gonadal sex reversal of triploid female (XXX) rainbow trout (Oncorhynchus mykiss).

    PubMed

    Xu, Gefeng; Huang, Tianqing; Jin, Xian; Cui, Cunhe; Li, Depeng; Sun, Cong; Han, Ying; Mu, Zhenbo

    2016-02-01

    In non-mammalian vertebrates, estrogens and expressions of cyp19a1 and foxl2 play critical roles in maintaining ovary differentiation and development, while dmrt1 and sox9 are male-specific genes in testicular differentiation and are highly conserved. In order to deeply understand the morphological change, sex steroids level and molecular mechanism of triploid female gonadal reversal in rainbow trout, we studied the ovary morphology, tendency of estradiol-17β (E2) and testosterone (T) levels and the relative expressions of dmrt1, cyp19a1, sox9 and foxl2 in juvenile and adult fish. Our results demonstrated that the development of triploid female gonads in rainbow trout went through arrested development, oocytes dedifferentiation, ovary reconstruction and sex reversal finally. During early gonadal development (154-334 days post-fertilization), the expressions of foxl2 and cyp19a1 increased linearly, while expressions of dmrt1 and sox9 were extremely suppressed, and E2 level was higher, while T level was lower. During the mid-to-late period of triploid female gonadal development (574-964 days post-fertilization), the expressions of dmrt1 and sox9 remained high and were very close to the quantity of diploid male genes, and T levels were even reaching diploid male plasma concentrations, while expressions of cyp19a1 and foxl2 were decreased, leading to decrease in E2 level. We realized that the development model of rainbow trout triploid female gonads was extremely rare, and the regulatory mechanism was very special. Genes involved in gonadal development and endogenous estrogens are pivotal factors in fish natural sex reversal.

  12. In Silico analysis of perturbed steroidogenesis and gonad growth in fathead minnows (P. promelas) exposed to 17α-ethynylestradiol.

    PubMed

    Hala, David; Petersen, Lene H; Martinović, Dalma; Huggett, Duane B

    2015-06-01

    The multi-factorial nature of adverse reproductive effects mediated by endocrine disrupting compounds (or EDCs) makes understanding the mechanistic basis of reproductive dysfunction a highly pertinent area of research. As a consequence, a main motivator for continued research is to integrate 'multi-leveled' complexity (i.e., from genes to phenotype) using mathematical methods capable of encapsulating properties of physiological relevance. In this study, an in silico stoichiometric model of piscine steroidogenesis was augmented with a 'biomass' reaction associating the underlying stoichiometry of steroidogenesis with a reaction representative of gonad growth. The ability of the in silico model to predict perturbed steroidogenesis and subsequent effects on gonad growth was tested by exposing reproductively active male and female fathead minnows (Pimephales promelas) to 88 ng/L of the synthetic estrogen, 17α-ethynylestradiol (EE2). The in silico model was parameterized (or constrained) with experimentally quantified concentrations of selected steroid hormones (using mass spectrometry) and fold changes in gene expression (using RT-qPCR) for selected steroidogenic enzyme genes, in gonads of male and female fish. Once constrained, the optimization framework of flux balance analysis (FBA) was used to calculate an optimal flux through the biomass reaction (analogous to gonad growth) and associated steroidogenic flux distributions required to generate biomass. FBA successfully predicted effects of EE2 exposure on fathead minnow gonad growth (%gonadosomatic index or %GSI) and perturbed production of steroid hormones. Specifically, FBA accurately predicted no effects of exposure on male %GSI and a significant reduction for female %GSI. Furthermore, in silico simulations accurately identified disrupted reaction fluxes catalyzing productions of androgens (in male fish) and progestogens (in female fish), an observation which agreed with in vivo experimentation. The analyses

  13. Disruption of apoptosis pathways involved in zebrafish gonad differentiation by 17α-ethinylestradiol and fadrozole exposures.

    PubMed

    Luzio, Ana; Matos, Manuela; Santos, Dércia; Fontaínhas-Fernandes, António A; Monteiro, Sandra M; Coimbra, Ana M

    2016-08-01

    Zebrafish (Danio rerio) sex determination seems to involve genetic factors (GSD) but also environmental factors (ESD), such as endocrine disrupting chemicals (EDCs) that are known to mimic endogenous hormones and disrupt gonad differentiation. Apoptosis has also been proposed to play a crucial role in zebrafish gonad differentiation. Nevertheless, the interactions between EDCs and apoptosis have received little attention. Thus, this study aimed to assess if and which apoptotic pathways are involved in zebrafish gonad differentiation and how EDCs may interfere with this process. With these purposes, zebrafish were exposed to 17α-ethinylestradiol (EE2, 4ng/L) and fadrozole (Fad, 50μg/L) from 2h to 35days post-fertilization (dpf). Afterwards, a gene expression analysis by qRT-PCR and a stereological analysis, based on systematic sampling and protein immunohistochemistry, were performed. The death receptors (FAS; TRADD), anti-apoptotic (BCL-2; MDM2), pro-apoptotic (CASP-2 and -6) and cell proliferation (BIRC5/survivin; JUN) genes and proteins were evaluated. In general, apoptosis was inhibited in females through the involvement of anti-apoptotic pathways, while in males apoptosis seemed to be crucial to the failure of the "juvenile ovary" development and the induction of testes transformation. The JUN protein was shown to be necessary in juvenile ovaries, while the BIRC5 protein seemed to be involved in zebrafish spermatogenesis. Both EDCs, EE2 and Fad, increased the apoptosis stimulus in zebrafish gonad. It was noticed that the few females that were resistant to Fad-induced sex reversal had increased anti-apoptotic factor levels, while males exposed to EE2 showed increased pro-apoptotic genes/proteins and were more advanced in gonad differentiation. Overall, our findings show that apoptosis pathways are involved in zebrafish gonad differentiation and that EDCs can disrupt this process.

  14. A portable electro-immobilization and laparoscopy system for sex determination and gonadal biopsy in largemouth bass Micropterus salmoides.

    PubMed

    Matsche, M A

    2013-11-01

    A portable electro-immobilization and laparoscopy system is described that is suitable for sex determination, gonadal biopsy and immediate release of largemouth bass Micropterus salmoides. Continuous direct current at a power density of 52·2 µW cm⁻¹ for 2 min was sufficient to immobilize fish for surgery, but induced a mild, transient hypokalaemia and hyperglycaemia. Insertion of a 4·8 mm laparoscopic instrument set through the urogenital pore provided access to the gonads for examination and biopsy with mild tissue trauma. PMID:24580673

  15. A portable electro-immobilization and laparoscopy system for sex determination and gonadal biopsy in largemouth bass Micropterus salmoides.

    PubMed

    Matsche, M A

    2013-11-01

    A portable electro-immobilization and laparoscopy system is described that is suitable for sex determination, gonadal biopsy and immediate release of largemouth bass Micropterus salmoides. Continuous direct current at a power density of 52·2 µW cm⁻¹ for 2 min was sufficient to immobilize fish for surgery, but induced a mild, transient hypokalaemia and hyperglycaemia. Insertion of a 4·8 mm laparoscopic instrument set through the urogenital pore provided access to the gonads for examination and biopsy with mild tissue trauma.

  16. Gonadal and Adrenal Abnormalities in Drug Users: Cause or Consequence of Drug Use Behavior and Poor Health Outcomes.

    PubMed

    Brown, Todd T; Wisniewski, Amy B; Dobs, Adrian S

    2006-01-01

    Opiates and cocaine both have effects on adrenal and gonadal function. Opiates suppress the hypothalamic-pituitary adrenal (HPA) axis, whereas cocaine leads to HPA activation. Opiates also cause gonadal dysfunction in both men and women. During withdrawal from opiates and cocaine, the HPA axis is activated which may reinforce relapse behavior. This review describes these hormonal effects and explores the potential consequences, including the effects on mood cognition and cardiovascular risk. Modification of the drug-induced hormonal dysfunction may represent a treatment strategy for drug rehabilitation.

  17. Studies on the antitumor activity and isolation of the glycoprotein from the gonad of Chlamys (Azumapecten) farreri

    NASA Astrophysics Data System (ADS)

    Gu, Qian-Qun; Fang, Yu-Chun; Wang, Chang-Yun; Xiao, Hang; Qin, Yu-Qing

    1998-12-01

    After being degreased with acetone, the female gonad of Chlamys (Azumapecten) farreri was extracted with water, and then subjected to DEAE—cellulose column chromatography and purified by Sephadex G-100 chromatography to obtain a pure female gonad glycoprotein (FGGP). The IR spectra, electrophoresis and chemical analysis of FGGP indicated that it was a kind of acid glycoprotein and that the content of total protein and sugar were 54.8% and 40%, respectively. Pharmacological tests showed that FGGP could inhibit (inhibition rate of 40.87%) the growth of Sarcoma 180 of mice.

  18. GONAD: A Novel CRISPR/Cas9 Genome Editing Method that Does Not Require Ex Vivo Handling of Embryos.

    PubMed

    Gurumurthy, Channabasavaiah B; Takahashi, Gou; Wada, Kenta; Miura, Hiromi; Sato, Masahiro; Ohtsuka, Masato

    2016-01-01

    Transgenic technologies used for creating a desired genomic change in animals involve three critical steps: isolation of fertilized eggs, microinjection of transgenic DNA into them and their subsequent transfer to recipient females. These ex vivo steps have been widely used for over 3 decades and they were also readily adapted for the latest genome editing technologies such as ZFNs, TALENs, and CRISPR/Cas9 systems. We recently developed a method called GONAD (Genome editing via Oviductal Nucleic Acids Delivery) that does not require all the three critical steps of transgenesis and therefore relieves the bottlenecks of widely used animal transgenic technologies. Here we provide protocols for the GONAD system.

  19. Endogenous control of sexual size dimorphism: Gonadal androgens have neither direct nor indirect effect on male growth in a Madagascar ground gecko (Paroedura picta).

    PubMed

    Kubička, Lukáš; Starostová, Zuzana; Kratochvíl, Lukáš

    2015-12-01

    Changes in the effect of gonadal androgens on male growth are considered as a possible mechanism allowing shifts in magnitude and even direction of sexual size dimorphism in vertebrates, particularly squamate reptiles. Positive effects of gonadal androgens on male growth were found in several male-larger species of lizards. Contrastingly, we document that in the male-larger Madagascar ground gecko (Paroedura picta) gonadal androgens do not affect male growth under constant thermal conditions. However, the absence of a thermal gradient might prevent the potential indirect effect of gonadal androgens on growth via the influence of circulating hormones on an individual's thermoregulation and hence metabolic rate. In order to study this, we monitored the growth and body temperature of socially isolated sham-operated and castrated males of the same species in a thermal gradient. We also compared the oxygen consumption and activity between the treatment groups in the open field to test the effect of gonadal hormones on these traits potentially affecting growth. Even under a thermal gradient we found no effect of gonadal androgens on growth rate or final body dimensions. Castration also did not significantly affect oxygen consumption or activity in the open field test. Together with our previous findings, we can exclude both the direct effect of male gonadal androgens on the ontogeny of sexual size dimorphism via the influence on the growth axis, and the indirect influence of gonadal androgens acting on the ontogeny of SSD through the effect on thermoregulation, metabolic rate and activity. PMID:26431613

  20. Endogenous control of sexual size dimorphism: Gonadal androgens have neither direct nor indirect effect on male growth in a Madagascar ground gecko (Paroedura picta).

    PubMed

    Kubička, Lukáš; Starostová, Zuzana; Kratochvíl, Lukáš

    2015-12-01

    Changes in the effect of gonadal androgens on male growth are considered as a possible mechanism allowing shifts in magnitude and even direction of sexual size dimorphism in vertebrates, particularly squamate reptiles. Positive effects of gonadal androgens on male growth were found in several male-larger species of lizards. Contrastingly, we document that in the male-larger Madagascar ground gecko (Paroedura picta) gonadal androgens do not affect male growth under constant thermal conditions. However, the absence of a thermal gradient might prevent the potential indirect effect of gonadal androgens on growth via the influence of circulating hormones on an individual's thermoregulation and hence metabolic rate. In order to study this, we monitored the growth and body temperature of socially isolated sham-operated and castrated males of the same species in a thermal gradient. We also compared the oxygen consumption and activity between the treatment groups in the open field to test the effect of gonadal hormones on these traits potentially affecting growth. Even under a thermal gradient we found no effect of gonadal androgens on growth rate or final body dimensions. Castration also did not significantly affect oxygen consumption or activity in the open field test. Together with our previous findings, we can exclude both the direct effect of male gonadal androgens on the ontogeny of sexual size dimorphism via the influence on the growth axis, and the indirect influence of gonadal androgens acting on the ontogeny of SSD through the effect on thermoregulation, metabolic rate and activity.

  1. Life history strategies in zooplankton communities: The significance of female gonad morphology and maturation types for the reproductive biology of marine calanoid copepods

    NASA Astrophysics Data System (ADS)

    Niehoff, Barbara

    2007-07-01

    The present review addresses the reproductive strategies of marine calanoid copepods, as affected by their physiological preconditioning, and aims to enhance understanding of their adaptations to specific environmental conditions. Knowledge about oocyte development and internal gonad structure, especially in relation to feeding conditions, is essential for a complete understanding of the reproductive strategies of the copepods. Therefore, the foci of the review are to identify general patterns in oocyte and gonad development in calanoid copepod species from marine ecosystems worldwide and to elucidate the significance of gonad structures for reproductive strategies. Oogenesis is similar in all copepod species. During maturation, the morphology of the oocytes changes distinctly and, according to oocyte size and appearance of ooplasm and nucleus, five oocyte developmental stages are distinguished. In contrast, the gonad structure and its changes during the spawning cycle differ considerably among species, and these differences are related to specific reproductive traits. Four gonad morphology types can be distinguished: the Calanus-type, found in species from all over the world with distinctly different life history traits, is apparently most common in calanoid copepods. In this gonad type, most oocyte developmental stages are present simultaneously, and usually many oocytes mature synchronously, all of which are released in one clutch. The gonad structure allows frequent spawning and large clutches, hence, high egg production rates. This may be a preconditioning for exploiting seasonally high food supply. However, the Calanus-type was also found in species producing eggs at lower rates. In the diverticula of Pseudocalanus-type gonads, only two oocyte developmental stages are present and usually fewer oocytes mature synchronously. Accordingly, the egg production rate is generally lower as compared to the Calanus-type, and apparently only this gonad-type is

  2. Subchronic effects of cadmium on the gonads, expressions of steroid hormones and sex-related genes in tilapia Oreochromis niloticus.

    PubMed

    Luo, Yongju; Shan, Dan; Zhong, Huan; Zhou, Yi; Chen, Wenzhi; Cao, Jinling; Guo, Zhongbao; Xiao, Jun; He, Fulin; Huang, Yifan; Li, Jian; Huang, Heming; Xu, Pao

    2015-12-01

    Cadmium (Cd) is one of the most toxic heavy metals in aquatic ecosystem which affects fish health and aquaculture. In the present study, we examined the bioaccumulation of Cd in the gonads of tilapia via dissolved and dietary routes. We evaluated the subchronic effects of Cd on the histology of gonads, steroid hormone levels and sex-related gene expressions in tilapia. In addition, we also studied maternal transfer of Cd. Our results indicated that Cd was accumulated significantly in both ovary and testis from both exposure routes. Histopathological analysis showed that Cd induced ovary and testis injuries. Estradiol levels were significantly increased in dissolved Cd exposed female fish. In addition, the Cd exposure displayed different effects on gene expressions in gonads. In females, the estrogen receptor (ERα) was stimulated in dissolved Cd-exposed fish at 70.32 and 143.78 μg/L for 30 days and in fish at 143.78 μg/L for 60 days. Vitellogenin expression was significantly down-regulated in the ovary of dissolved Cd-exposed fish. In testis, GR expression was elevated after 60 days of dissolved Cd and dietary exposure. Furthermore, Cd level was significantly higher in the eggs than that in the fry. Our results demonstrated that both dissolved and dietary Cd exposures affected gonad development by altering steroid hormone levels and sex-related gene expressions in tilapia. PMID:26471182

  3. Elimination of short-day melatonin signaling accelerates gonadal recrudescence but does not break refractoriness in male Turkish hamsters.

    PubMed

    Jarjisian, Stephan G; Zucker, Irving

    2011-04-01

    Long days stimulate and short days (SDs) inhibit the reproductive axis of photoperiodic rodents. In long-day Turkish hamsters, unlike most other rodents, elimination of pineal melatonin secretion by constant light or pinealectomy initiates a cycle of gonadal involution and recrudescence outwardly similar to that induced by short days. The present study assessed whether short days and constant light induce the seasonal reproductive cycle via common or different interval timing mechanisms. Male hamsters that had undergone gonadal involution in SDs for 8 or 14 weeks were treated with LL for 14 and 8 weeks, respectively. If SDs and LL act via independent mechanisms, then gonadal quiescence of SD-regressed males, which normally lasts 10 weeks, might be extended by LL treatment; alternatively, if SDs and LL act on the same timer, or the timer cannot be retriggered, then LL will not extend the duration of reproductive quiescence. Neither of these outcomes materialized. Instead, male hamsters exposed to LL while reproductively quiescent exhibited accelerated gonadal recrudescence. Extended LL treatment did not restore responsiveness to SDs in photorefractory hamsters. In Turkish hamsters, photoperiodic history determines whether constant light inhibits or stimulates the hypothalamic-pituitary-testicular axis.

  4. In boys with abnormal developmental tempo, maturation of the skeleton and the hypothalamic-pituitary-gonadal axis remains synchronous.

    PubMed

    Flor-Cisneros, Armando; Leschek, Ellen W; Merke, Deborah P; Barnes, Kevin M; Coco, Marilena; Cutler, Gordon B; Baron, Jeffrey

    2004-01-01

    The primary mechanism that initiates puberty is unknown. One possible clue is that pubertal maturation often parallels skeletal maturation. Conditions that delay skeletal maturation also tend to delay the onset of puberty, whereas conditions that accelerate skeletal maturation tend to hasten the onset of puberty. To examine this relationship, we studied boys with congenital adrenal hyperplasia (n = 13) and familial male-limited precocious puberty (n = 22), two conditions that accelerate maturational tempo, and boys with idiopathic short stature (n = 18) in which maturational tempo is sometimes delayed. In all three conditions, the onset of central puberty generally occurred at an abnormal chronological age but a normal bone age. Boys with the greatest skeletal advancement began central puberty at the earliest age, whereas boys with the greatest skeletal delay began puberty at the latest age. Furthermore, the magnitude of the skeletal advancement or delay matched the magnitude of the pubertal advancement or delay. This synchrony between skeletal maturation and hypothalamic-pituitary-gonadal axis maturation was observed among patients within each condition and also between conditions. In contrast, the maturation of the hypothalamic-pituitary-gonadal axis did not remain synchronous with other maturational processes including weight, height, or body mass index. We conclude that in boys with abnormal developmental tempo, maturation of the skeleton and the hypothalamic-pituitary-gonadal axis remains synchronous. This synchrony is consistent with the hypothesis that in boys, skeletal maturation influences hypothalamic-pituitary-gonadal axis maturation.

  5. Predicting Adaptive Response to Fadrozole Exposure:Computational Model of the Fathead MinnowsHypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict doseresponse and time-course (...

  6. Predicting Adaptive Response to Fadrozole Exposure: Computational Model of the Fathead Minnow Hypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (...

  7. RNAi-Mediated Gene Silencing in a Gonad Organ Culture to Study Sex Determination Mechanisms in Sea Turtle

    PubMed Central

    Sifuentes-Romero, Itzel; Merchant-Larios, Horacio; Milton, Sarah L.; Moreno-Mendoza, Norma; Díaz-Hernández, Verónica; García-Gasca, Alejandra

    2013-01-01

    The autosomal Sry-related gene, Sox9, encodes a transcription factor, which performs an important role in testis differentiation in mammals. In several reptiles, Sox9 is differentially expressed in gonads, showing a significant upregulation during the thermo-sensitive period (TSP) at the male-promoting temperature, consistent with the idea that SOX9 plays a central role in the male pathway. However, in spite of numerous studies, it remains unclear how SOX9 functions during this event. In the present work, we developed an RNAi-based method for silencing Sox9 in an in vitro gonad culture system for the sea turtle, Lepidochelys olivacea. Gonads were dissected as soon as the embryos entered the TSP and were maintained in organ culture. Transfection of siRNA resulted in the decrease of both Sox9 mRNA and protein. Furthermore, we found coordinated expression patterns for Sox9 and the anti-Müllerian hormone gene, Amh, suggesting that SOX9 could directly or indirectly regulate Amh expression, as it occurs in mammals. These results demonstrate an in vitro method to knockdown endogenous genes in gonads from a sea turtle, which represents a novel approach to investigate the roles of important genes involved in sex determination or differentiation pathways in species with temperature-dependent sex determination. PMID:24705165

  8. Silencing of Gonad-Inhibiting Hormone Transcripts in Litopenaeus vannamei Females by use of the RNA Interference Technology.

    PubMed

    Feijó, Rubens G; Braga, André L; Lanes, Carlos F C; Figueiredo, Márcio A; Romano, Luis A; Klosterhoff, Marta C; Nery, Luis E M; Maggioni, Rodrigo; Wasielesky, Wilson; Marins, Luis F

    2016-02-01

    The method usually employed to stimulate gonadal maturation and spawning of captive shrimp involves unilateral eyestalk ablation, which results in the removal of the endocrine complex responsible for gonad-inhibiting hormone (GIH) synthesis and release. In the present study, RNAi technology was used to inhibit transcripts of GIH in Litopenaeus vannamei females. The effect of gene silencing on gonad development was assessed by analyzing the expression of GIH and vitellogenin, respectively, in the eyestalk and ovaries of L. vannamei females, following ablation or injection with dsRNA-GIH, dsRNA-IGSF4D (non-related dsRNA), or saline solution. Histological analyses were performed to determine the stage of gonadal development and to assess the diameter of oocytes throughout the experimental procedure. Only oocytes at pre-vitellogenesis and primary vitellogenesis stages were identified in females injected with dsRNA-GIH, dsRNA-IGSF4D, or saline solution. Oocytes at all developmental stages were observed in eyestalk-ablated females, with predominance of later stages, such as secondary vitellogenesis and mature oocytes. Despite achieving 64, 73, and 71% knockdown of eyestalk GIH mRNA levels by 15, 30, and 37 days post-injection (dpi), respectively, in dsRNA-GIH-injected females, the expected increase in ovary vitellogenin mRNA expression was only observed on the 37th dpi. This is the first report of the use of RNAi technology to develop an alternative method to eyestalk ablation in captive L. vannamei shrimps.

  9. [Hormonal activity of the hypophysis-gonadal system in male hamadryas baboons in relationship to their hierarchical position].

    PubMed

    Taranov, A G; Shashk-ogly, L K; Goncharov, N P

    1986-03-01

    Hierarchic status-dependent hormonal activity of pituitary-gonadal system was studied in an isolated group of hamadryas baboons. Testosterone level was higher in dominating males. The level of sex hormone was higher in aged animals with great muscle mass. No correlation was observed between hierarchic status of hamadryas baboon males and the blood level of luteinizing hormone.

  10. Insulin and IGF1 receptors are essential for XX and XY gonadal differentiation and adrenal development in mice.

    PubMed

    Pitetti, Jean-Luc; Calvel, Pierre; Romero, Yannick; Conne, Béatrice; Truong, Vy; Papaioannou, Marilena D; Schaad, Olivier; Docquier, Mylène; Herrera, Pedro Luis; Wilhelm, Dagmar; Nef, Serge

    2013-01-01

    Mouse sex determination provides an attractive model to study how regulatory genetic networks and signaling pathways control cell specification and cell fate decisions. This study characterizes in detail the essential role played by the insulin receptor (INSR) and the IGF type I receptor (IGF1R) in adrenogenital development and primary sex determination. Constitutive ablation of insulin/IGF signaling pathway led to reduced proliferation rate of somatic progenitor cells in both XX and XY gonads prior to sex determination together with the downregulation of hundreds of genes associated with the adrenal, testicular, and ovarian genetic programs. These findings indicate that prior to sex determination somatic progenitors in Insr;Igf1r mutant gonads are not lineage primed and thus incapable of upregulating/repressing the male and female genetic programs required for cell fate restriction. In consequence, embryos lacking functional insulin/IGF signaling exhibit (i) complete agenesis of the adrenal cortex, (ii) embryonic XY gonadal sex reversal, with a delay of Sry upregulation and the subsequent failure of the testicular genetic program, and (iii) a delay in ovarian differentiation so that Insr;Igf1r mutant gonads, irrespective of genetic sex, remained in an extended undifferentiated state, before the ovarian differentiation program ultimately is initiated at around E16.5.

  11. Gonadal Morphology and Gametogenesis in Japanese Red Coral Corallium japonicum (Octocorallia: Alcyonacea) Collected off Cape Ashizuri, Japan.

    PubMed

    Sekida, Satoko; Iwasaki, Nozomu; Okuda, Kazuo

    2016-06-01

    Colonies of the Japanese red coral Corallium japonicum Kishinouye, 1903 collected off Cape Ashizuri, Japan were gonochoric and produced gonads in siphonozooids annually, mainly during the spring season. Polyp anatomy, gonadal morphology and gametogenesis in this species were revealed by light and electron microscopy. A siphonozooid had a pharynx with a prominent siphonoglyph and eight mesenteries: two sulcal, two asulcal, and four lateral. A rudimentary retractor was found on one side of each mesoglea of these mesenteries. The retractor arrangement in the siphonozooid was reverse of what was described in the autozooids of octocorals. Gonads initiated as small protrusions on the mesenteries, except in the asulcal ones, and even at an incipient stage they were covered with a sac-shaped thin layer of mesoglea, which was continuous with the mesoglea of mesenteries. Gastrodermis enveloped the complete outer surface of the thin layer of mesoglea throughout gametogenesis in both oocytes and sperm cysts. Oocytes produced many microvilli on their cortical surfaces beneath the thin layer of mesoglea concomitantly with the accumulation of lipid globules in the cells, whereas in sperm cysts spermatocytes and spermatids increased in number without microvilli production, followed by synchronous spermiogenesis involving remarkable changes in the shape and position of organelles. Based on the comparison of patterns in gonadal development between octocorals including C. japonicum, hexacorals and scyphozoans, octocoral and stauromedusa species may be characterized by the fact that gametogenesis never occurs in the matrix of mesoglea, but rather exclusively within the thin sac of mesoglea surrounded by gastrodermis. PMID:27268987

  12. Adaptive Response in Female Fathead Minnows Exposed to an Aromatase Inhibitor: Computational Modeling of the Hypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course ...

  13. Promotion of haematopoietic activity in embryonic stem cells by the aorta-gonad-mesonephros microenvironment

    SciTech Connect

    Krassowska, Anna; Gordon-Keylock, Sabrina; Samuel, Kay; Gilchrist, Derek; Dzierzak, Elaine; Oostendorp, Robert; Forrester, Lesley M. . E-mail: l.forrester@ed.ac.uk; Ansell, John D.

    2006-11-01

    We investigated whether the in vitro differentiation of ES cells into haematopoietic progenitors could be enhanced by exposure to the aorta-gonadal-mesonephros (AGM) microenvironment that is involved in the generation of haematopoietic stem cells (HSC) during embryonic development. We established a co-culture system that combines the requirements for primary organ culture and differentiating ES cells and showed that exposure of differentiating ES cells to the primary AGM region results in a significant increase in the number of ES-derived haematopoietic progenitors. Co-culture of ES cells on the AM20-1B4 stromal cell line derived from the AGM region also increases haematopoietic activity. We conclude that factors promoting the haematopoietic activity of differentiating ES cells present in primary AGM explants are partially retained in the AM20.1B4 stromal cell line and that these factors are likely to be different to those required for adult HSC maintenance.

  14. Retinoic acid and meiosis induction in adult versus embryonic gonads of medaka

    PubMed Central

    Adolfi, Mateus C.; Herpin, Amaury; Regensburger, Martina; Sacquegno, Jacopo; Waxman, Joshua S.; Schartl, Manfred

    2016-01-01

    In vertebrates, one of the first recognizable sex differences in embryos is the onset of meiosis, known to be regulated by retinoic acid (RA) in mammals. We investigated in medaka a possible meiotic function of RA during the embryonic sex determination (SD) period and in mature gonads. We found RA mediated transcriptional activation in germ cells of both sexes much earlier than the SD stage, however, no such activity during the critical stages of SD. In adults, expression of the RA metabolizing enzymes indicates sexually dimorphic RA levels. In testis, RA acts directly in Sertoli, Leydig and pre-meiotic germ cells. In ovaries, RA transcriptional activity is highest in meiotic oocytes. Our results show that RA plays an important role in meiosis induction and gametogenesis in adult medaka but contrary to common expectations, not for initiating the first meiosis in female germ cells at the SD stage. PMID:27677591

  15. Mechanisms of arsenic disruption on gonadal, adrenal and thyroid endocrine systems in humans: A review.

    PubMed

    Sun, Hong-Jie; Xiang, Ping; Luo, Jun; Hong, Huachang; Lin, Hongjun; Li, Hong-Bo; Ma, Lena Q

    2016-10-01

    Due to its toxicity as a carcinogen and wide distribution in the environment, arsenic (As) exposure in humans is of public concern globally. Many studies have manifested that As exposure induces cancers besides pathological effects in humans. Animal studies showed that chronic As exposure induces serious neurological effects. Based on recent studies, researchers proposed that As, including arsenate (AsV) and arsenite (AsIII), is also an endocrine disruptor. This review discusses the mechanisms of As toxicity on three endocrine systems including gonadal, adrenal and thyroid endocrine systems. Arsenic methylation and oxidative stress are responsible for As-induced disorders of endocrine systems, however, strong binding of AsIII to thiols also play an important role. Some studies showed AsV toxicity on endocrine systems, but mechanistic investigation is lacking. Research is needed to look into their toxicity mechanisms to help cure the illnesses caused by As-induced endocrine system disorders.

  16. Modulation of the hypothalamic-pituitary-gonadal axis by selective ligands of the KISS1R.

    PubMed

    Thompson, Emily L; Murphy, Kevin G

    2010-04-01

    The kisspeptin/kisspeptin receptor (KISS1R) system is a critical regulator of reproductive function. The kisspeptins are potent stimulators of the hypothalamic-pituitary-gonadal (HPG) axis via their actions ongonadotropin-releasing hormone. Therefore, kisspeptins represent putative drug targets for the treatment of reproductive diseases. Kisspeptins of 10, 13, 14 and 54 amino acids in length have been identified, all of which contain a C-terminal decapeptide that is essential for biological activity. The longest form, kisspeptin-54, may be the most bioactive in vivo. Moreover, the pattern of kisspeptin administration is important; whereas single or intermittent injections of kisspeptin generally stimulate the HPG axis, continuous administration leads to the desensitization of the HPG axis to the effects of the peptide. Several kisspeptin analogs have been developed, and are discussed in relation to their activity at the KISS1R and to their in vivo HPG axis effects.

  17. Adaptive interactions between cytokines and the hypothalamic-pituitary-gonadal axis.

    PubMed

    Cannon, J G

    1998-09-29

    Circulating and tissue concentrations of pyrogenic cytokines, especially interleukin (IL)-1 beta, vary temporally through the menstrual cycle and pregnancy. The secretion of these cytokines in vitro by isolated human mononuclear cells is significantly influenced by exogenous gonadal steroids and gonadotropins. Reciprocally, cytokines influence gonadotropin secretion by the pituitary and steroidogenesis by the ovaries and testes. Several hypotheses have been advanced regarding the adaptive value of these interrelationships. Cytokine-induced synthesis of proteolytic enzymes and extracellular matrix proteins may be important for the tissue remodeling necessary for ovulation, implantation, and delivery. Tolerance of the fetal allograft may require downregulation of cytotoxic effector cells and reciprocal upregulation of humoral and nonspecific host defenses. The inhibitory influence of IL-1 beta on the luteinizing hormone surge may prevent inopportune conception, and the abortive influences of tumor necrosis factor-alpha and gamma interferon may terminate pregnancy during periods of infection.

  18. Dysregulation of the hypothalamic-pituitary-gonadal axis in experimental autoimmune encephalomyelitis and multiple sclerosis.

    PubMed

    Foster, Scott C; Daniels, Crystal; Bourdette, Dennis N; Bebo, Bruce F

    2003-07-01

    The ability of sex hormones to regulate cytokine production is well established, but the ability of cytokines to regulate sex hormone production has only begun to be investigated. We measured sex hormones in mice with passive experimental autoimmune encephalomyelitis (EAE) and in multiple sclerosis (MS) patients with sexual dysfunction. Abnormally low serum testosterone levels were found in male mice with EAE and in male MS patients, while serum estrogen levels in female mice with EAE were normal. An inverse relationship between cytokine and testosterone levels in male mice with EAE, coupled with an increase in serum luteinizing hormone (LH) levels, suggests that inflammatory cytokines suppress testosterone production by a direct effect on testicular Leydig cells. Gender differences in the sensitivity of the hypothalamic-pituitary-gonadal (HPG) axis to inflammation may be an important factor regulating the duration and severity of central nervous system (CNS) autoimmunity.

  19. Kisspeptins: regulators of metastasis and the hypothalamic-pituitary-gonadal axis.

    PubMed

    Murphy, K G

    2005-08-01

    The kisspeptins are the peptide products of the KiSS-1 gene and the endogenous agonists for the GPR54 receptor. Although KiSS-1 was initially discovered as a metastasis suppressor gene, recent evidence suggests the kisspeptin/GPR54 system is a key regulator of the reproductive system. Disrupted GPR54 signalling causes hypogonadotrophic hypogonadism in rodents and man. Central or peripheral administration of kisspeptin potently stimulates the hypothalamic-pituitary-gonadal axis, increasing circulating gonadotrophin concentrations in a number of animal models. These effects appear likely to be mediated via the hypothalamic gonadotrophin-releasing hormone system, although kisspeptins may have direct effects on the anterior pituitary gland. Hypothalamic KiSS-1 expression is regulated by circulating sex steroids. The precise physiological role of the kisspeptin system in the regulation of reproductive function remains to be elucidated.

  20. Effects of dopamine receptor stimulation on opiate-induced modifications of pituitary-gonadal function.

    PubMed

    Vescovi, P P; Pezzarossa, A; Ceresini, G; Rastelli, G; Valenti, G; Gerra, G

    1985-01-01

    We evaluated the effects of the dopaminergic drug bromocriptine (Br) on prolactin (PRL), luteinizing hormone (LH) and testosterone (Te) levels in a homogeneous group of opiate addicts in a methadone maintenance program (20 mg twice daily). Basal blood levels of PRL, LH and Te were determined in 15 adult male drug addicts, before 30 and 60 days after Br administration (7.5 mg/day) was started. 15 healthy volunteers served as controls for the evaluation of basal values of the hormones. Before treatment PRL values were high, while LH and Te levels were lower than normal. 30 days later, PRL lowered significantly while LH and Te increased significantly. 60 days later, the blood hormone values were still significantly different from pretreatment values, and close to the normal range. This observation shows that Br, probably through an increase of dopaminergic tone, may counteract some effects of opiates on the hypothalamic-pituitary-gonadal axis.

  1. Pituitary-gonadal response to acute I.M. stimulation with clomiphene citrate in normal men.

    PubMed

    Miechi, H R; Turner, D; Guitelman, A; Aparicio, N J; Schwarzstein, L

    1975-06-01

    In order to asses the effect of acute i.m. injection of clomiphene citrate (CC) on LH, FSH, and testosterone (T) secretion, five normal, fertile men received 5 mg of the drug dissolved in 2 ml 0.9% saline, while a further five were injected 10 mg of the same preparation. All tests were performed at 8 a.m. Blood samples were drawn at 0, 30, 60, 120 and 180 minutes of the injection. Serum LH, FSH, and T values were determined by the double antibody radioimmunoassay technique. A significant rise of the LH, FSH, and T levels was obtained in both groups. Peak LH values were obtained at 30 minutes (average), whereas FSH and T peaks occurred at 60 minutes. The 180-minute values were similar to basal. The results seem to indicate that intramsucularly administered CC could be useful, as a rapid test, in evaluating the function of the hypothalamic-pituitary-gonadal axis.

  2. Paramethasone acetate (PA): corticosteroid potency vs hypothalamic pituitary-gonadal axis.

    PubMed

    Cortés-Gallegos, V; Alonso, R; Castañeda, G; Sojo, I; Carranco, A; Cervantes, C; Parra, A

    1984-01-01

    Because paramethasone acetate (PA) suppresses basal and midcycle LH surge and blocks estrogen synthesis in the female, its possible effect upon testicular physiology was evaluated in 13 healthy men by measuring the circulating levels of FSH, LH, prolactin (PRL), testosterone (T), dihydrotestosterone (DHT), androstenedione (A), estradiol (E2) and cortisol (C) every 4 h throughout the day, before (control) and after PA (6 mg/d/7 d). The total concentrations of each hormone, as well as the PA-induced suppressibility (measured as percent decrease in the mean 24 h plasma level) were analyzed. PA suppressed neither the basal nor circadian rhythm of T and had no effect on LH, FSH or PRL output. DHT, A, E2 were significantly reduced and the basal concentrations and circadian variations of C were abolished. PA showed a dual control on the pituitary gonadal axis and while causing a maximal suppressed adrenocortical activity it had no interference in testosterone synthesis.

  3. Hypothalamic-pituitary gonadal axis in boys with primary hypothyroidism and macroorchidism.

    PubMed

    Castro-Magaña, M; Angulo, M; Cañas, A; Sharp, A; Fuentes, B

    1988-03-01

    Nine of 15 boys with severe long-standing primary hypothyroidism were found to have macroorchidism. All 15 patients had elevated thyroid-stimulating hormone levels. However, only those patients with testicular enlargement had striking elevations of serum prolactin and gonadotropin values. The response to gonadotropin-releasing hormone in our patients was blunted, in contradistinction to that of children with true precocious puberty. In spite of the elevated levels of luteinizing hormone, the serum testosterone levels were in the prepubertal range, explaining the lack of peripheral manifestations of androgenic effect. Improvement of testosterone secretion followed decreasing prolactin levels with bromocriptine administration, suggesting an inhibitory effect of prolactin on luteinizing hormone action at the Leydig cell. We conclude that testicular enlargement is the result of continuous follicle-stimulating hormone stimulation and that the term "true precocious puberty" is not appropriate in children with hypothyroidism and macroorchidism unless the hypothalamic-pituitary gonadal axis is shown to be at the pubertal stage.

  4. DMRT1 protects male gonadal cells from retinoid-dependent sexual transdifferentiation

    PubMed Central

    Minkina, Anna; Matson, Clinton K.; Lindeman, Robin E.; Ghyselinck, Norbert B.; Bardwell, Vivian J.; Zarkower, David

    2014-01-01

    Summary Mammalian sex determination initiates in the fetal gonad with specification of bipotential precursor cells into male Sertoli cells or female granulosa cells. This choice was long presumed to be irreversible, but genetic analysis in the mouse recently revealed that sexual fates must be maintained throughout life. Somatic cells in the testis or ovary, even in adults, can be induced to transdifferentiate to their opposite-sex equivalents by loss of a single transcription factor, DMRT1 in the testis or FOXL2 in the ovary. Here we ask what mechanism DMRT1 prevents from triggering transdifferentiation. We find that DMRT1 blocks testicular retinoic acid (RA) signaling from activating genes normally involved in female sex determination and ovarian development and show that inappropriate activation of these genes can drive sexual transdifferentiation. By preventing activation of potential feminizing genes, DMRT1 allows Sertoli cells to participate in RA signaling, which is essential for reproduction, without being sexually reprogrammed. PMID:24856513

  5. DMRT1 protects male gonadal cells from retinoid-dependent sexual transdifferentiation.

    PubMed

    Minkina, Anna; Matson, Clinton K; Lindeman, Robin E; Ghyselinck, Norbert B; Bardwell, Vivian J; Zarkower, David

    2014-06-01

    Mammalian sex determination initiates in the fetal gonad with specification of bipotential precursor cells into male Sertoli cells or female granulosa cells. This choice was long presumed to be irreversible, but genetic analysis in the mouse recently revealed that sexual fates must be maintained throughout life. Somatic cells in the testis or ovary, even in adults, can be induced to transdifferentiate to their opposite-sex equivalents by loss of a single transcription factor, DMRT1 in the testis or FOXL2 in the ovary. Here, we investigate what mechanism DMRT1 prevents from triggering transdifferentiation. We find that DMRT1 blocks testicular retinoic acid (RA) signaling from activating genes normally involved in female sex determination and ovarian development and show that inappropriate activation of these genes can drive sexual transdifferentiation. By preventing activation of potential feminizing genes, DMRT1 allows Sertoli cells to participate in RA signaling, which is essential for reproduction, without being sexually reprogrammed. PMID:24856513

  6. Sex differences in anxiety disorders: Interactions between fear, stress, and gonadal hormones.

    PubMed

    Maeng, Lisa Y; Milad, Mohammed R

    2015-11-01

    This article is part of a Special Issue "SBN 2014". Women are more vulnerable to stress- and fear-based disorders, such as anxiety and post-traumatic stress disorder. Despite the growing literature on this topic, the neural basis of these sex differences remains unclear, and the findings appear inconsistent. The neurobiological mechanisms of fear and stress in learning and memory processes have been extensively studied, and the crosstalk between these systems is beginning to explain the disproportionate incidence and differences in symptomatology and remission within these psychopathologies. In this review, we discuss the intersect between stress and fear mechanisms and their modulation by gonadal hormones and discuss the relevance of this information to sex differences in anxiety and fear-based disorders. Understanding these converging influences is imperative to the development of more effective, individualized treatments that take sex and hormones into account.

  7. Experiment K-6-19. Pineal physiology in microgravity: Relation to rat gonadal function

    NASA Technical Reports Server (NTRS)

    Holley, D.; Soliman, M. R. I.; Kaddis, F.; Markley, C.; Krasnov, I.

    1990-01-01

    One of the most interesting concomitants to spaceflight and exposure to microgravity has been the disturbing alteration in calcium metabolism and resulting skeletal effects. It was recognized as early as 1685 (cited in Kitay and Altschule, 1954) that the pineal of humans calcified with age. However, little can be found in the literature relating calcification and pineal function. Given the link between exposure to microgravity and perturbation of calcium metabolism and the fact that the pineal is apparently one of the only soft tissues to calcify, researchers examined pineal calcium content following the spaceflight. Researchers concluded that the spaceflight resulted in a stress response as indicated by adrenal hypertrophy, that gonadal function was compromised, and that the pineal may be linked as part of the mechanism of the responses noted.

  8. Mechanisms of arsenic disruption on gonadal, adrenal and thyroid endocrine systems in humans: A review.

    PubMed

    Sun, Hong-Jie; Xiang, Ping; Luo, Jun; Hong, Huachang; Lin, Hongjun; Li, Hong-Bo; Ma, Lena Q

    2016-10-01

    Due to its toxicity as a carcinogen and wide distribution in the environment, arsenic (As) exposure in humans is of public concern globally. Many studies have manifested that As exposure induces cancers besides pathological effects in humans. Animal studies showed that chronic As exposure induces serious neurological effects. Based on recent studies, researchers proposed that As, including arsenate (AsV) and arsenite (AsIII), is also an endocrine disruptor. This review discusses the mechanisms of As toxicity on three endocrine systems including gonadal, adrenal and thyroid endocrine systems. Arsenic methylation and oxidative stress are responsible for As-induced disorders of endocrine systems, however, strong binding of AsIII to thiols also play an important role. Some studies showed AsV toxicity on endocrine systems, but mechanistic investigation is lacking. Research is needed to look into their toxicity mechanisms to help cure the illnesses caused by As-induced endocrine system disorders. PMID:27502899

  9. Differentiation of mesenchymal stem cells into gonad and adrenal steroidogenic cells

    PubMed Central

    Yazawa, Takashi; Imamichi, Yoshitaka; Miyamoto, Kaoru; Umezawa, Akihiro; Taniguchi, Takanobu

    2014-01-01

    Hormone replacement therapy is necessary for patients with adrenal and gonadal failure. Steroid hormone treatment is also employed in aging people for sex hormone deficiency. These patients undergo such therapies, which have associated risks, for their entire life. Stem cells represent an innovative tool for tissue regeneration and the possibility of solving these problems. Among various stem cell types, mesenchymal stem cells have the potential to differentiate into steroidogenic cells both in vivo and in vitro. In particular, they can effectively be differentiated into steroidogenic cells by expressing nuclear receptor 5A subfamily proteins (steroidogenic factor-1 and liver receptor homolog-1) with the aid of cAMP. This approach will provide a source of cells for future regenerative medicine for the treatment of diseases caused by steroidogenesis deficiencies. It can also represent a useful tool for studying the molecular mechanisms of steroidogenesis and its related diseases. PMID:24772247

  10. Identification and comparison of gonadal transcripts of testis and ovary of adult common carp Cyprinus carpio using suppression subtractive hybridization.

    PubMed

    Chen, Jian-Jun; Xia, Xiao-Hua; Wang, Li-Fang; Jia, Yong-Fang; Nan, Ping; Li, Li; Chang, Zhong-Jie

    2015-06-01

    The limited number of gonad-specific and gonad-related genes that have been identified in fish represents a major obstacle in the study of fish gonad development and sex differentiation. In common carp Cyprinus carpio from China's Yellow River, the ovary and testis differ in volume and weight in adult fish of the same age. Comparing sperm, egg, and somatic cell transcripts in this carp may provide insight into the mechanisms of its gonad development and sex differentiation. In the present work, gene expression patterns in the carp ovary and testis were compared using suppression subtractive hybridization. Two bidirectional subtracted complementary DNA (cDNA) libraries were analyzed in parallel using testis or ovary as testers. Eighteen nonredundant clones were identified in the male library, including 15 known cDNAs. The expression patterns of selected genes in testis and ovary were analyzed using reverse transcriptase polymerase chain reaction. Tektin-1, GAPDS, FGFIBP, IGFBP-5, and an unknown gene from the Ccmg4 clone were observed to be expressed only in testis. GSDF, BMI1b, Wt1a, and an unknown gene from the Ccme2 clone were expressed at higher levels in testis than in ovary at sexual maturity. Thirty functional expressed sequence tags (ESTs) were identified in 43 sequenced clones in the female library, including 28 known cDNAs, one uncharacterized cDNA (EST clone), and one novel sequence. Eight identified ESTs showed significant differences in expression between the testis and the ovary. ZP3C and Psmb2 were expressed exclusively in ovary, whereas the expression levels of IFIPGL-1, Setd6, ATP-6, CDC45, AIF-1, and an unknown gene from the Ccfh2 clone were more strongly expressed in ovary than in testis. In addition, the expression of ZP3C, Wt1a, and Setd6 was analyzed in male and female gonads, heart, liver, kidney, and brain. ZP3C was expressed only in ovary. Setd6 expression was significantly stronger in female tissues than that in the male, except in the liver

  11. Mechanism of action of endosulfan as disruptor of gonadal steroidogenesis in the cichlid fish Cichlasoma dimerus.

    PubMed

    Da Cuña, Rodrigo H; Rey Vázquez, Graciela; Dorelle, Luciana; Rodríguez, Enrique M; Guimarães Moreira, Renata; Lo Nostro, Fabiana L

    2016-09-01

    The organochlorine pesticide endosulfan (ES) is used in several countries as a wide spectrum insecticide on crops with high commercial value. Due to its high toxicity to non-target animals, its persistence in the environment and its ability to act as an endocrine disrupting compound in fish, ES use is currently banned or restricted in many other countries. Previous studies on the cichlid fish Cichlasoma dimerus have shown that waterborne exposure to ES can lead to both decreased pituitary FSH content and histological alterations of testes. As gonadotropin-stimulated sex steroids release from gonads was inhibited by ES in vitro, the aim of the present study was to elucidate possible mechanisms of disruption of ES on gonadal steroidogenesis in C. dimerus, as well as compare the action of the active ingredient (AI) with that of currently used commercial formulations (CF). Testis and ovary fragments were incubated with ES (AI or CF) and/or steroidogenesis activators or precursors. Testosterone and estradiol levels were measured in the incubation media. By itself, ES did not affect hormone levels. Co-incubation with LH and the adenylate cyclase activator forskolin caused a decrease of the stimulated sex steroids release. When co-incubated with precursors dehydroandrostenedione and 17αhydroxyprogesterone, ES did not affect the increase caused by their addition alone. No differences were observed between the AI and CFs, suggesting that the effect on steroidogenesis disruption is mainly caused by the AI. Results indicate that action of ES takes place downstream of LH-receptor activation and upstream of the studied steroidogenic enzymes. PMID:27235598

  12. Radiation Dose to the Thyroid and Gonads in Patients Undergoing Cardiac CT Angiography

    PubMed Central

    Behroozi, Hamid; Davoodi, Mohammad; Aghasi, Shahriar

    2015-01-01

    Background: The present data show a global increase in the rate of cardiovascular disease. Cardiac CT angiography has developed as a fast and non-invasive cardiac imaging modality following the introduction of multi-slice computed tomogaraphy. Objectives: The aim of this study was to measure the radiation dose to the thyroid and pelvis regions in patients undergoing cardiac CT angiography using the Care Dose 4D method of 64-slice scanner. Patients and Methods: Eighty-one patients (41 males and 40 females) who were diagnosed with suspected coronary artery disease and were referred to Golestan Hospital, Imaging Department were recruited. Inclusion criteria were based on the protocol of multi-slice CT coronary angiography. The radiation dose to the thyroid and pelvis regions was measured using thermo luminescent dosimeters (TLDs). Results: The mean radiation dose to the thyroid in male and female subjects was 0.32 mSv and 0.41 mSv, respectively (P = 0.032) (total mean, 0.36 mSv). The mean radiation dose to the pelvis in male and female subjects was 81 μSv and 112 μSv, respectively (P = 0.026) (total mean, 96.5 μSv), Conclusions: The total mean radiation dose to the thyroid and gonads was 0.36 mSv, and 96.5 μSv, respectively for the subjects. These values were high for one organ in a single study. Gender can affect the radiation dose to the thyroid and gonads. This can be attributed to the anatomical characteristic differences of the male and female subjects. PMID:26060556

  13. Measuring Faecal Epi-Androsterone as an Indicator of Gonadal Activity in Spotted Hyenas (Crocuta crocuta).

    PubMed

    Pribbenow, Susanne; East, Marion L; Ganswindt, Andre; Tordiffe, Adrian S W; Hofer, Heribert; Dehnhard, Martin

    2015-01-01

    Enzyme immunoassays (EIA) that measure faecal testosterone metabolites (fTM) are useful tools to monitor gonadal activity. The aim of this study was to validate an "in-house" epiandrosterone EIA to monitor fTM in spotted hyenas. FTM were characterised in a male and a female hyena that each received an injection of 3H-testosterone. High-performance liquid chromatography (HPLC) analyses revealed a cluster of highly polar enzyme-hydrolysable hormone metabolite conjugates. We performed hydrolysis using β-glucuronidase to deconjugate metabolites and improve sensitivity of the assay. Because β-glucuronidase from Helix pomatia has been reported to bias testosterone measurements in some species, we compared the enzymatic activity of the commonly used β-glucuronidase extracted from H. pomatia with the same enzyme from Escherichia coli. Our results showed that β-glucuronidases from both sources produced similar results from spotted hyena faeces. We therefore hydrolysed samples with H. pomatia enzymes. HPLC analyses also demonstrated that following hydrolysis the epiandrosterone EIA measured significant amounts of immunoreactive metabolites corresponding to radiolabelled metabolites in both sexes. Additionally, HPLC and GC-MS analyses confirmed the presence of epiandrosterone in faeces of spotted hyenas. The biological relevance of the epiandrosterone EIA was validated by demonstrating (1) a significant increase in fTM levels in response to a testosterone injection within 16 h, (2) no biological responsiveness to an adrenocorticotropic hormone (ACTH) injection and (3) significant differences in fTM levels between juvenile males and adult immigrant males in a free-ranging wild population. Our results clearly demonstrate that the epiandrosterone EIA is a reliable non-invasive method to monitor gonadal activity in spotted hyenas. PMID:26107516

  14. Cyclosporine-induced alterations in the hypothalamic hypophyseal gonadal axis in transplant patients.

    PubMed

    Ramirez, G; Narvarte, J; Bittle, P A; Ayers-Chastain, C; Dean, S E

    1991-01-01

    We evaluated the response of 20 male patients, 13 cadaveric kidney and 7 heart transplant recipients, to the administration of 100 micrograms GnRH (gonadotropin-releasing hormone) and 500 micrograms TRH (thyrotropic-releasing hormone). All of the heart transplant recipients and 7 of the kidney transplant patients were receiving a combination of cyclosporine, azathioprine and prednisone; while the 6 remaining kidney transplant patients received azathioprine and prednisone. The patients receiving cyclosporine had decreased plasma levels of prolactin, and manifested a blunted response to TRH administration for prolactin and TSH. The heart transplant patients had a blunted response of LH and FSH to the administration of GnRH. The levels of testosterone were found to be low in all patients regardless of the immunosuppressant therapy. Despite the low testosterone levels, no increment in the concentration of LH or FSH was present. Intramuscular administration of HCG (human chorionic gonadotropin) (Ayerst Laboratories, New York, N.Y.) failed to increase the testosterone concentration in 5 of 6 patients with renal transplants, 3 taking cyclosporine and 3 taking azathioprine. This study suggests that cyclosporine has a selective effect on the hypothalamus and/or hypophysis, resulting in lower baseline levels of plasma prolactin and a pituitary insensitivity to TRH administration. In addition, FSH and LH were low or normal in the presence of low testosterone levels, suggesting that the hypothalamic pituitary gonadal axis is impaired. Furthermore, there may be a direct toxic effect of the immunosuppressant medications on the gonads, manifested as lower testosterone levels and inability to respond to the administration of HCG.

  15. The influence of hyperthyroidism on the hypothalamic-pituitary-gonadal axis.

    PubMed

    Zähringer, S; Tomova, A; von Werder, K; Brabant, G; Kumanov, P; Schopohl, J

    2000-01-01

    We have investigated the function of the hypothalamic-pituitary-gonadal (H-P-G)-axis in patients with severe, untreated Graves' disease. We studied 7 male and 6 female healthy volunteers, and 7 male and 7 female patients with Graves' disease. Hormone profiles were developed by blood sampling every 10 min for an 8 hour period. In women this was done in the early follicular phase of menstrual cycle. LH-, FSH-, and PRL levels were measured using immunoradiometric assays and testosterone (T), estradiol (E2), sex-hormone binding globulin (SHBG), and progesterone (P) were measured with standard assays. The pulsatility of LH, FSH and PRL was calculated using the programmes Pulsar, Cluster and Desade. The temporal relationship of plasma LH, FSH, and PRL pulses was also investigated using specific concordance analysis. Data were evaluated by means of non-parametric statistics. LH-secretion was increased in all hyperthyroid patients, while FSH-secretion was increased in hyperthyroid men only. Pulsatile characteristics of LH- and FSH-secretion (frequency, peak shape) in patients were not different from controls. No change in PRL-secretion was shown. Significant copulsatility occurred between LH and FSH, and LH and PRL. This was more pronounced in hyperthyroid than in healthy study subjects. Plasma levels of steroid hormones and sex-hormone-binding globulin were significantly (p<0.005) increased in hyperthyroid men. Free Androgen Index was significantly (p<0.005) decreased in hyperthyroid males. No other auto immune diseases were noticed. Our results indicate that the function of the H-P-G axis is not impaired in hyperthyroid patients, but gonadotropin levels are increased. Hyperthyroid men show relative primary gonadal insufficiency that may be due to exaggerated SHBG levels. The copulsatility of LH and FSH, and of LH and PRL was confirmed both in patients and controls.

  16. Ethanol: its adverse effects upon the hypothalamic-pituitary-gonadal axis.

    PubMed

    Gavaler, J S; Urso, T; Van Thiel, D H

    1983-01-01

    Considerable evidence has accrued over the preceding two decades to establish that ethanol is a gonadal toxin. In the male such toxicity is both direct, being expressed at the level of the hypothalamus and/or pituitary. Moreover, such toxicity is due in part to direct ethanol exposure and also in part to the consequences of ethanol metabolism (e.g., acetaldehyde generation, redox changes and alterations in enzyme levels and activities). Thus as a result of studies performed both in man and in animals, it has been shown conclusively that ethanol abuse per se, and not the associated liver disease that occurs with alcohol abuse, is responsible for the impotence, loss of libido, and testicular atrophy which are seen commonly in chronic alcoholic men. With prolonged alcohol abstinence, recent studies have suggested that spontaneous recovery of normal sexual function is possible in some chronic alcoholic men if testicular atrophy has not yet occurred and if their responses to clomiphene and/or luteinizing hormone releasing factor stimulation are normal. In contrast, abstinent alcoholic men with either overt testicular atrophy or inadequate responses to such pharmacologic challenges fail to recover despite continued alcoholic abstinence. Such men will require either a penile prosthesis or long-term oral androgen therapy to achieve "acceptable" sexual functioning. Considerably less information is available concerning the adverse effects of ethanol and alcohol abuse in women. The available data however, suggests that women, like men, develop gonadal injury as a consequence of alcohol abuse and that such injury occurs both at the level of the ovary and at the level of the hypothalamus and pituitary.

  17. Serum angiotensinogen concentration in relation to gonadal hormones, body size, and genotype in growing young people.

    PubMed

    Pratt, J H; Ambrosius, W T; Tewksbury, D A; Wagner, M A; Zhou, L; Hanna, M P

    1998-11-01

    Multiple factors are thought to influence the level of circulating angiotensinogen (AGT). We showed previously that the serum AGT concentration was significantly related to body mass index (BMI) in a cohort of young people. In the present study, we studied whether levels of the gonadal hormones estradiol and testosterone might also predict the AGT level and might contribute to the BMI effect, since both the production of these hormones and BMI increase with age. In boys (n=127; mean+/-SD age, 14.7+/-1.9 years) and girls (n=104; age, 14.8+/-1.9 years) studied as a single group, we found a significant association of AGT level with level of estradiol (P=0.015) after adjustment for haplotype, age, race, testosterone concentration, and BMI. In girls studied alone, the level of AGT showed a significantly positive relation to level of testosterone (P=0.043), possibly a result of peripheral conversion of testosterone to estradiol, after adjustment for haplotype, age, race, estradiol concentration, and BMI. In boys, on the other hand, the level of testosterone was inversely related to AGT concentration (P=0.019), again after making adjustments for the other variables. Finally, in pairs of subjects matched for BMI, age, race, and gender where 1 member of each pair had either 1 or 2 copies of an AGT gene haplotype (T235 and -1074t) and the other member had no copy, the level of AGT was higher in the carrier of a haplotype in 24 of the 34 pairs (P<0.001). In conclusion, gonadal hormones are an additional influence on the circulating level of AGT in growing young people. In addition, with matching for BMI and other covariates, there is a strong association of AGT genotype with the serum level of AGT, emphasizing the importance of AGT gene expression as a determinant of the circulating level of AGT. PMID:9822447

  18. Daily Rhythms of the Expression of Key Genes Involved in Steroidogenesis and Gonadal Function in Zebrafish.

    PubMed

    Di Rosa, Viviana; López-Olmeda, Jose Fernando; Burguillo, Ana; Frigato, Elena; Bertolucci, Cristiano; Piferrer, Francesc; Sánchez-Vázquez, Francisco Javier

    2016-01-01

    Fish present daily and seasonal rhythms in spawning and plasmatic levels of steroids that control reproduction. However, the existence of the rhythms of expression of the genes that underlie the endocrine mechanisms responsible for processes such as steroidogenesis and reproduction in fish have still been poorly explored to date. Here we investigated the daily pattern of the expression of key genes involved in sex steroid production that ultimately set the sex ratio in fish. Adult zebrafish were maintained under a 12:12 h light-dark cycle at a constant temperature of 27°C and were sampled every 4 h during a 24-hour cycle. The expression of key genes in the gonads and brains of female and male individuals were analyzed. In gonads, the expression of aromatase (cyp19a1a, ovarian aromatase) and the antimüllerian hormone (amh, testis) was rhythmic, with almost opposite acrophases: ZT 5:13 h (in the light phase) and ZT 15:39 h (at night), respectively. The expression of foxl2 (forkhead box L2) was also rhythmic in the ovary (acrophase located at ZT 5:02 h) and the expression of dmrt1 (doublesex and mab-3-related transcription factor 1) was rhythmic in testes (acrophase at ZT 18:36 h). In the brain, cyp19a1b (brain aromatase) and cyp11b (11beta-hydroxylase) presented daily differences, especially in males, where the expression peaked at night. These results provide the first evidence for marked time-of-the-day-dependent differences in the expression of the genes involved in sex ratio control, which should be considered when investigating processes such as reproduction, sex differentiation and steroidogenesis in fish. PMID:27322588

  19. [Bio- and immunoactive luteinizing hormone in negative feedback action of gonadal steroids].

    PubMed

    Takahashi, A

    1985-05-20

    To clarify the possible intervention of gonadal steroids on the secretion of bioactive LH from the pituitary, the levels of plasma LH were measured by in vitro bioassay as well as radioimmunoassay, and their changes in specific endocrine conditions were investigated. The ratio of bioactivity to immunoactivity (B/I ratio) of LH in patients with hypergonadotropic hypogonadism and in postmenopausal women was significantly greater than that in women during the follicular phase of the menstrual cycle, and estradiol levels in the former groups were significantly lower than those of the latter group. In cases of gonadotropin-secreting pituitary tumor with high LH and normal estradiol levels, B/I ratio was found at a level similar to that during the follicular phase. The administration of combined pills decreased the high B/I ratio of oophorectomized women to levels comparable to those in the normal follicular phase. Although bioactive LH responded in all groups to LH-RH with a similar pattern to that observed with immunoactive LH with a peak value 15 approximately 30 min. after the stimulation, followed by a gradual decrease thereafter, the B/I ratio of women during the follicular phase was the lowest at 15 min. and returned up to the initial value within 60 min. after the injection of LH-RH. In contrast, this drop of the B/I ratio did not occur in 7 out of 15 cases composed either of hypergonadotropic hypogonadism or postmenopausal women. The peak values of LH in patients without decrease in B/I ratios were higher than those of women showing decreased B/I ratios. In addition, circulating levels of gonadotropin alpha-subunit did not affect the B/I ratio. These results suggest that circulating levels of gonadal steroids regulate the secretion and synthesis of LH quantitatively as well as qualitatively.

  20. Measuring Faecal Epi-Androsterone as an Indicator of Gonadal Activity in Spotted Hyenas (Crocuta crocuta)

    PubMed Central

    Pribbenow, Susanne; East, Marion L.; Ganswindt, Andre; Tordiffe, Adrian S. W.; Hofer, Heribert; Dehnhard, Martin

    2015-01-01

    Enzyme immunoassays (EIA) that measure faecal testosterone metabolites (fTM) are useful tools to monitor gonadal activity. The aim of this study was to validate an “in-house” epiandrosterone EIA to monitor fTM in spotted hyenas. FTM were characterised in a male and a female hyena that each received an injection of 3H-testosterone. High-performance liquid chromatography (HPLC) analyses revealed a cluster of highly polar enzyme-hydrolysable hormone metabolite conjugates. We performed hydrolysis using β-glucuronidase to deconjugate metabolites and improve sensitivity of the assay. Because β-glucuronidase from Helix pomatia has been reported to bias testosterone measurements in some species, we compared the enzymatic activity of the commonly used β-glucuronidase extracted from H. pomatia with the same enzyme from Escherichia coli. Our results showed that β-glucuronidases from both sources produced similar results from spotted hyena faeces. We therefore hydrolysed samples with H. pomatia enzymes. HPLC analyses also demonstrated that following hydrolysis the epiandrosterone EIA measured significant amounts of immunoreactive metabolites corresponding to radiolabelled metabolites in both sexes. Additionally, HPLC and GC-MS analyses confirmed the presence of epiandrosterone in faeces of spotted hyenas. The biological relevance of the epiandrosterone EIA was validated by demonstrating (1) a significant increase in fTM levels in response to a testosterone injection within 16 h, (2) no biological responsiveness to an adrenocorticotropic hormone (ACTH) injection and (3) significant differences in fTM levels between juvenile males and adult immigrant males in a free-ranging wild population. Our results clearly demonstrate that the epiandrosterone EIA is a reliable non-invasive method to monitor gonadal activity in spotted hyenas. PMID:26107516

  1. Nitroreductase-mediated gonadal dysgenesis for infertility control of genetically modified zebrafish.

    PubMed

    Hu, Shao-Yang; Lin, Pei-Yu; Liao, Chia-Hsuan; Gong, Hong-Yi; Lin, Gen-Hwa; Kawakami, Koichi; Wu, Jen-Leih

    2010-10-01

    Genetically modified (GM) fish with desirable features such as rapid growth, disease resistance, and cold tolerance, among other traits, have been established in aquaculture. However, commercially available GM fish are restricted because of global concerns over the incomplete assessments of food safety and ecological impact. The ecological impact concerns include gene flow and escape of the GM fish, which may cause extinction of wild natural fish stocks. Infertility control is a core technology for overcoming this obstacle. Although polyploidy technology, GnRH-specific antisense RNA, and RNAi against GnRH gene expression have been used to cause infertility in fish, these approaches are not 100% reliable and are not heritable. In the present study, zebrafish was used as a model to establish an inducible platform of infertility control in GM fish. Nitroreductase, which converts metronidazole substrate into cytotoxin, was fused with EGFP and expressed specifically by oocytes in the Tg(ZP:NTR-EGFP) by a zona pellucida promoter. Through consecutive immersion of metronidazole from 28 to 42 days posthatching, oocyte-specific EGFP expression was eliminated, and atrophy of the gonads was detected by anatomical analysis. These findings reveal that oocyte-specific nitroreductase-mediated catalysis of metronidazole blocks oogenesis and leads to an undeveloped oocyte. Furthermore, oocyte cell death via apoptosis was detected by a TUNEL assay. We found that the gonadal dysgenesis induced by metronidazole resulted in activation of the ovarian killer gene bok, which is a proapoptotic gene member of the Bcl-2 family and led to infertility. These results show that oocyte-specific nitroreductase-mediated catalysis of metronidazole can cause reliable infertility in zebrafish and could potentially be used as a model for other aquaculture fish species.

  2. Measuring Faecal Epi-Androsterone as an Indicator of Gonadal Activity in Spotted Hyenas (Crocuta crocuta).

    PubMed

    Pribbenow, Susanne; East, Marion L; Ganswindt, Andre; Tordiffe, Adrian S W; Hofer, Heribert; Dehnhard, Martin

    2015-01-01

    Enzyme immunoassays (EIA) that measure faecal testosterone metabolites (fTM) are useful tools to monitor gonadal activity. The aim of this study was to validate an "in-house" epiandrosterone EIA to monitor fTM in spotted hyenas. FTM were characterised in a male and a female hyena that each received an injection of 3H-testosterone. High-performance liquid chromatography (HPLC) analyses revealed a cluster of highly polar enzyme-hydrolysable hormone metabolite conjugates. We performed hydrolysis using β-glucuronidase to deconjugate metabolites and improve sensitivity of the assay. Because β-glucuronidase from Helix pomatia has been reported to bias testosterone measurements in some species, we compared the enzymatic activity of the commonly used β-glucuronidase extracted from H. pomatia with the same enzyme from Escherichia coli. Our results showed that β-glucuronidases from both sources produced similar results from spotted hyena faeces. We therefore hydrolysed samples with H. pomatia enzymes. HPLC analyses also demonstrated that following hydrolysis the epiandrosterone EIA measured significant amounts of immunoreactive metabolites corresponding to radiolabelled metabolites in both sexes. Additionally, HPLC and GC-MS analyses confirmed the presence of epiandrosterone in faeces of spotted hyenas. The biological relevance of the epiandrosterone EIA was validated by demonstrating (1) a significant increase in fTM levels in response to a testosterone injection within 16 h, (2) no biological responsiveness to an adrenocorticotropic hormone (ACTH) injection and (3) significant differences in fTM levels between juvenile males and adult immigrant males in a free-ranging wild population. Our results clearly demonstrate that the epiandrosterone EIA is a reliable non-invasive method to monitor gonadal activity in spotted hyenas.

  3. Osteoporosis and its association with non-gonadal hormones involved in hypertension, adiposity and hyperglycaemia.

    PubMed

    Poudyal, Hemant; Brown, Lindsay

    2013-12-01

    Osteoporosis is a high-prevalence disease, particularly in developed countries, and results in high costs both to the individual and to society through associated fragility fractures. There is an urgent need for identification of novel drug targets and development of new anti-osteoporotic agents. Between 30 and 80% of osteoporotic fractures cannot be prevented despite current treatments achieving relative fracture risk reduction of up to 20%, 50%, and 70% for non-vertebral, hip and spine fractures, respectively. Traditionally, the decline in gonadal hormones has been studied as the sole hormonal determinant for the loss of bone mineral density in osteoporosis. However, recent studies have identified receptors for numerous non-gonadal hormones such as PTH, angiotensin II, leptin, adiponectin, insulin and insulin-like growth factor-1 on the osteoblast lineage cells that directly regulate bone turnover. These hormones are also involved in the pathogenesis of metabolic syndrome risk factors, particularly hypertension, type-II diabetes and obesity. By activating their respective receptors on osteoblastic lineage cells, these hormones appear to act through a common mechanism by down-regulating receptors for activation of nuclear factor kappa B ligand (RANKL) and up-regulating osteoprotegerin (OPG) with inverse responses for adiponectin. Receptors for amylin, gastric inhibitory polypeptide and ghrelin and have also been identified on the osteoblast lineage cells although the roles of these receptors in bone turnover are controversial or poorly studied. Moreover, bone turnover may be independently regulated by modulation of osteoclast-osteoblast function and bone marrow adiposity. Leptin appears to be the only hormone that is a known regulator of both bone mineralisation and bone adiposity.

  4. Gonadal status and reproductive function following treatment for Hodgkin's disease in childhood: The Stanford experience

    SciTech Connect

    Ortin, T.T.; Shostak, C.A.; Donaldson, S.S. )

    1990-10-01

    To ascertain the impact of therapy on gonadal function and reproductive outcome among children treated for Hodgkin's disease, we reviewed the experience at Stanford University Medical Center during the years 1965-1986. There were 240 children 15 years of age or younger, 92 girls and 148 boys; with median follow-up of 9 years, maximum follow-up was 26 years. Of this cohort, data on gonadal function were available on 20 boys, 5 of whom were considered prepubescent; they had no clinical evidence of sexual maturation and were less than 13 years of age. Evaluation of the boys included testicular biopsy, semen analyses and the ability to procreate. Serum gonadotropin hormone levels (FSH, LH) were studied in 11 boys who also had semen analyses. Sexual maturation was attained in all boys without the need for androgen replacement. Among the eight boys treated with radiation alone, four were able to father a child (3 following 40-45 Gy pelvic radiation dose, 1 without pelvic radiation) from 3-19 years following treatment. Three others who received 30-44 Gy pelvic radiation were oligospermic when tested at 10 to 15 years post-treatment. Semen analyses in 10 of 12 (83%) boys who had been treated with six cycles of MOPP with or without pelvic radiation revealed absolute azoospermia with no evidence of recovery as along as 11 years of follow-up. Following prolonged azoospermia, 2 of the 12 boys (17%) had recovery of fertility, with normalization of sperm count and/or ability to procreate at 12 and 15 years following treatment. There was no correlation with serum gonadotropin levels and sterility. Data on menstrual history, pregnancy and offspring were available in 86 (92%) of the girls. Seventy-five of the 86 girls (87%) have normal menstrual function. However, none of the females who underwent pelvic radiation without prior oophoropexy has maintained ovarian function.

  5. Naltrexone effects on pituitary and gonadal hormones in male and female rhesus monkeys.

    PubMed

    Mello, N K; Mendelson, J H; Bree, M P; Skupny, A

    1988-11-01

    The long-acting opioid antagonist, naltrexone, stimulates LH and FSH in women during the early follicular phase of the menstrual cycle and is a new provocative test of hypothalamic-pituitary function (42,63). The acute effects of naltrexone (0.25, 0.50 and 1.0 mg/kg IV) on anterior pituitary (LH, FSH, PRL) and gonadal steroid (T or E2) hormones were studied in 7 female and 4 male rhesus monkeys (Macaca mulatta). Integrated plasma samples were collected at 20 min intervals for 60 min before and for 300 min after intravenous infusion of naltrexone over 10 min. In females studied during the early follicular phase (cycle days 1-3), naltrexone did not stimulate LH and significantly suppressed E2 (p less than 0.0003-0.0001) and FSH (p less than 0.006-0.0001). Naltrexone (0.50 and 1.0 mg/kg) also did not stimulate LH release in late follicular phase females (cycle days 10-12) when estradiol levels were in the peri-ovulatory range. FSH and E2 were significantly suppressed (p less than 0.01-0.05) after 1.0 mg/kg naltrexone, but not after 0.5 mg/kg naltrexone. However, in males all doses of naltrexone significantly stimulated LH (p less than 0.003-0.0001) and T (p less than 0.001-0.0001) but not FSH. LH increased significantly above baseline within 20 to 40 min and T increased significantly within 60 min. These gender differences in naltrexone's effects on pituitary gonadotropins and gonadal steroid hormones were unanticipated. These data are not concordant with clinical studies which report significant naltrexone stimulation of LH in men and in women during the early follicular phase.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3150786

  6. Daily Rhythms of the Expression of Key Genes Involved in Steroidogenesis and Gonadal Function in Zebrafish

    PubMed Central

    Di Rosa, Viviana; López-Olmeda, Jose Fernando; Burguillo, Ana; Frigato, Elena; Bertolucci, Cristiano; Piferrer, Francesc; Sánchez-Vázquez, Francisco Javier

    2016-01-01

    Fish present daily and seasonal rhythms in spawning and plasmatic levels of steroids that control reproduction. However, the existence of the rhythms of expression of the genes that underlie the endocrine mechanisms responsible for processes such as steroidogenesis and reproduction in fish have still been poorly explored to date. Here we investigated the daily pattern of the expression of key genes involved in sex steroid production that ultimately set the sex ratio in fish. Adult zebrafish were maintained under a 12:12 h light-dark cycle at a constant temperature of 27°C and were sampled every 4 h during a 24-hour cycle. The expression of key genes in the gonads and brains of female and male individuals were analyzed. In gonads, the expression of aromatase (cyp19a1a, ovarian aromatase) and the antimüllerian hormone (amh, testis) was rhythmic, with almost opposite acrophases: ZT 5:13 h (in the light phase) and ZT 15:39 h (at night), respectively. The expression of foxl2 (forkhead box L2) was also rhythmic in the ovary (acrophase located at ZT 5:02 h) and the expression of dmrt1 (doublesex and mab-3-related transcription factor 1) was rhythmic in testes (acrophase at ZT 18:36 h). In the brain, cyp19a1b (brain aromatase) and cyp11b (11beta-hydroxylase) presented daily differences, especially in males, where the expression peaked at night. These results provide the first evidence for marked time-of-the-day-dependent differences in the expression of the genes involved in sex ratio control, which should be considered when investigating processes such as reproduction, sex differentiation and steroidogenesis in fish. PMID:27322588

  7. Sequencing and De Novo Assembly of the Gonadal Transcriptome of the Endangered Chinese Sturgeon (Acipenser sinensis)

    PubMed Central

    Du, Hao; Zhang, Shuhuan; Wei, Qiwei

    2015-01-01

    Background The Chinese sturgeon (Acipenser sinensis) is endangered through anthropogenic activities including over-fishing, damming, shipping, and pollution. Controlled reproduction has been adopted and successfully conducted for conservation. However, little information is available on the reproductive regulation of the species. In this study, we conducted de novo transcriptome assembly of the gonad tissue to create a comprehensive dataset for A. sinensis. Results The Illumina sequencing platform was adopted to obtain 47,333,701 and 47,229,705 high quality reads from testis and ovary cDNA libraries generated from three-year-old A. sinensis. We identified 86,027 unigenes of which 30,268 were annotated in the NCBI non-redundant protein database and 28,281 were annotated in the Swiss-prot database. Among the annotated unigenes, 26,152 and 7,734 unigenes, respectively, were assigned to gene ontology categories and clusters of orthologous groups. In addition, 12,557 unigenes were mapped to 231 pathways in the Kyoto Encyclopedia of Genes and Genomes Pathway database. A total of 1,896 unigenes, potentially differentially expressed between the two gonad types, were found, with 1,894 predicted to be up-regulated in ovary and only two in testis. Fifty-five potential gametogenesis-related genes were screened in the transcriptome and 34 genes with significant matches were found. Besides, more paralogs of 11 genes in three gene families (sox, apolipoprotein and cyclin) were found in A. sinensis compared to their orthologs in the diploid Danio rerio. In addition, 12,151 putative simple sequence repeats (SSRs) were detected. Conclusions This study provides the first de novo transcriptome analysis currently available for A. sinensis. The transcriptomic data represents the fundamental resource for future research on the mechanism of early gametogenesis in sturgeons. The SSRs identified in this work will be valuable for assessment of genetic diversity of wild fish and genealogy

  8. Effects of 17 beta-estradiol exposure on Xenopus laevis gonadal histopathology.

    PubMed

    Wolf, Jeffrey C; Lutz, Ilka; Kloas, Werner; Springer, Timothy A; Holden, Larry R; Krueger, Henry O; Hosmer, Alan J

    2010-05-01

    The natural estrogen 17 beta-estradiol (E2) is a potential environmental contaminant commonly employed as a positive control substance in bioassays involving estrogenic effects. The aquatic anuran Xenopus laevis is a frequent subject of reproductive endocrine disruptor research; however, histopathological investigations have tended to be less than comprehensive. Consequently, a study was designed to characterize gross and microscopic changes in the gonads of X. laevis as a result of E2 exposure. Additional goals of this study, which consisted of three separate experiments, included the standardization of diagnostic terminology and criteria, the validation of statistical methodology, and the establishment of a half maximal effective concentration (EC50) for E2 as defined by an approximately 50% conversion of presumptive genotypic males to phenotypic females. In the first experiment, frogs were exposed to nominal concentrations of 0, 0.2, 1.5, or 6.0 microg/L E2. From these experimental results and those of a subsequent range finding trial, the EC50 for E2 was determined to be approximately 0.2 microg/L. This E2 concentration was utilized in the other two experiments, which were performed at different facilities to confirm the reproducibility of results. Experiments were conducted according to Good Laboratory Practice guidelines, and the histopathologic evaluations were peer reviewed by an independent pathologist. Among the three trials, the histopathological findings that were strongly associated with E2-exposure (p<0.001 to 0.0001) included an increase in the proportion of phenotypic females, mixed sex, dilated testis tubules, dividing gonocytes in the testis, and dilated ovarian cavities in phenotypic ovaries. A comparison of the gross and microscopic evaluations suggested that some morphologic changes in the gonads may potentially be missed if studies rely entirely on macroscopic assessment.

  9. Combined effects of androgen anabolic steroids and physical activity on the hypothalamic-pituitary-gonadal axis.

    PubMed

    Hengevoss, Jonas; Piechotta, Marion; Müller, Dennis; Hanft, Fabian; Parr, Maria Kristina; Schänzer, Wilhelm; Diel, Patrick

    2015-06-01

    Analysing effects of pharmaceutical substances and training on feedback mechanisms of the hypothalamic-pituitary-gonadal axis may be helpful to quantify the benefit of strategies preventing loss of muscle mass, and in the fight against doping. In this study we analysed combined effects of anabolic steroids and training on the hypothalamic-pituitary-gonadal axis. Therefore intact male Wistar rats were dose-dependently treated with metandienone, estradienedione and the selective androgen receptor modulator (SARM) S-1. In serum cortisol, testosterone, 17β-estradiol (E2), prolactin, inhibin B, follicle-stimulating hormone (FSH), luteinizing hormone (LH), Insulin-like growth factor 1 (IGF-1), and thyroxine (T4) concentrations were determined. Six human volunteers were single treated with 1-androstenedione. In addition abusing and clean body builders were analysed. Serum concentrations of inhibin B, IGF-1, cortisol, prolactin, T4, thyroid-stimulating hormone (TSH), testosterone and LH were determined. In rats, administration of metandienone, estradienedione and S-1 resulted in an increase of muscle fiber diameter. Metandienone and estradienedione but not S-1 administration significantly decreases LH and inhibin B serum concentration. Administration of estradienedione resulted in an increase of E2 and S-1 in an increase of cortisol. Single administration of 1-androstenedione in humans decreased cortisol and inhibin B serum concentrations. LH was not affected. In abusing body builders a significantly decrease of LH, TSH and inhibin B and an increase of prolactin, IGF-1 and T4 was detected. In clean body builders only T4 and TSH were affected. PMID:25797375

  10. Gonadal steroid–dependent effects on bone turnover and bone mineral density in men

    PubMed Central

    Finkelstein, Joel S.; Lee, Hang; Leder, Benjamin Z.; Goldstein, David W.; Hahn, Christopher W.; Hirsch, Sarah C.; Linker, Alex; Perros, Nicholas; Servais, Andrew B.; Taylor, Alexander P.; Webb, Matthew L.; Youngner, Jonathan M.; Yu, Elaine W.

    2016-01-01

    BACKGROUND. Severe gonadal steroid deficiency induces bone loss in adult men; however, the specific roles of androgen and estrogen deficiency in hypogonadal bone loss are unclear. Additionally, the threshold levels of testosterone and estradiol that initiate bone loss are uncertain. METHODS. One hundred ninety-eight healthy men, ages 20–50, received goserelin acetate, which suppresses endogenous gonadal steroid production, and were randomized to treatment with 0, 1.25, 2.5, 5, or 10 grams of testosterone gel daily for 16 weeks. An additional cohort of 202 men was randomized to receive these treatments plus anastrozole, which suppresses conversion of androgens to estrogens. Thirty-seven men served as controls and received placebos for goserelin and testosterone. Changes in bone turnover markers, bone mineral density (BMD) by dual-energy x-ray absorptiometry (DXA), and BMD by quantitative computed tomography (QCT) were assessed in all men. Bone microarchitecture was assessed in 100 men. RESULTS. As testosterone dosage decreased, the percent change in C-telopeptide increased. These increases were considerably greater when aromatization of testosterone to estradiol was also suppressed, suggesting effects of both testosterone and estradiol deficiency. Decreases in DXA BMD were observed when aromatization was suppressed but were modest in most groups. QCT spine BMD fell substantially in all testosterone-dose groups in which aromatization was also suppressed, and this decline was independent of testosterone dose. Estradiol deficiency disrupted cortical microarchitecture at peripheral sites. Estradiol levels above 10 pg/ml and testosterone levels above 200 ng/dl were generally sufficient to prevent increases in bone resorption and decreases in BMD in men. CONCLUSIONS. Estrogens primarily regulate bone homeostasis in adult men, and testosterone and estradiol levels must decline substantially to impact the skeleton. TRIAL REGISTRATION. ClinicalTrials.gov, NCT00114114

  11. Combined effects of androgen anabolic steroids and physical activity on the hypothalamic-pituitary-gonadal axis.

    PubMed

    Hengevoss, Jonas; Piechotta, Marion; Müller, Dennis; Hanft, Fabian; Parr, Maria Kristina; Schänzer, Wilhelm; Diel, Patrick

    2015-06-01

    Analysing effects of pharmaceutical substances and training on feedback mechanisms of the hypothalamic-pituitary-gonadal axis may be helpful to quantify the benefit of strategies preventing loss of muscle mass, and in the fight against doping. In this study we analysed combined effects of anabolic steroids and training on the hypothalamic-pituitary-gonadal axis. Therefore intact male Wistar rats were dose-dependently treated with metandienone, estradienedione and the selective androgen receptor modulator (SARM) S-1. In serum cortisol, testosterone, 17β-estradiol (E2), prolactin, inhibin B, follicle-stimulating hormone (FSH), luteinizing hormone (LH), Insulin-like growth factor 1 (IGF-1), and thyroxine (T4) concentrations were determined. Six human volunteers were single treated with 1-androstenedione. In addition abusing and clean body builders were analysed. Serum concentrations of inhibin B, IGF-1, cortisol, prolactin, T4, thyroid-stimulating hormone (TSH), testosterone and LH were determined. In rats, administration of metandienone, estradienedione and S-1 resulted in an increase of muscle fiber diameter. Metandienone and estradienedione but not S-1 administration significantly decreases LH and inhibin B serum concentration. Administration of estradienedione resulted in an increase of E2 and S-1 in an increase of cortisol. Single administration of 1-androstenedione in humans decreased cortisol and inhibin B serum concentrations. LH was not affected. In abusing body builders a significantly decrease of LH, TSH and inhibin B and an increase of prolactin, IGF-1 and T4 was detected. In clean body builders only T4 and TSH were affected.

  12. The Study of Gonadal Hormonal Abnormalities and Sexual Dysfunction in HIV Positive Females: An Exploratory Study

    PubMed Central

    Kallikadavil, Abithraj; Shivaswamy, Rajendraprasad; Menon, Vineetha Bharathan

    2016-01-01

    Introduction Every endocrine gland has been reported to be affected at varying rates in HIV. HIV is a highly stigmatized chronic disease with a substantial co-occurrence of mental and sexual health problems; however the sexual health problems in women have not been extensively studied. Aim To study the gonadal hormonal abnormalities and sexual dysfunction in HIV positive female patients and its possible association. Materials and Methods This descriptive/exploratory study was conducted in the Department of General Medicine at a tertiary care hospital from September 2013 to August 2015. The study group included 50 diagnosed HIV-positive patients. They were also subjected to specific questions regarding sexual dysfunction by female counselors using female sexual function index. Visits of the subjects were scheduled independent of the menstrual cycle. Hormonal levels (free testosterone, FSH, LH) were measured. Results Out of 50 patients, 26 patients in our study had sexual dysfunction (52%). Patients with age group between 30-39 years had the maximum sexual dysfunction compared to the other groups (<0.001). Patients with a CD4 count between 200 and 499 had the maximum sexual dysfunction (<0.02). Mean duration of HIV in the study was 30 months in sexual dysfunction group which was significant (p<0.005). Hormonal levels were found to be in normal range. All the study patients reported desire, arousal and lubrication problems whereas orgasm and satisfaction problems were noted in 60% patients with pain reported in 52%. Conclusion We identified that although the hormonal levels were in the normal range, they were comparatively in the lower range in the dysfunction group than the non-dysfunctional group. Both free testosterone and FSH levels were low indicating involvement of the pituitary rather than the gonads. We also conclude that duration of HIV and also level of CD4 count is related to sexual dysfunction. PMID:27190860

  13. Gonadal and extragonadal germ cell tumours in the United States, 1973-2007.

    PubMed

    Stang, A; Trabert, B; Wentzensen, N; Cook, M B; Rusner, C; Oosterhuis, J W; McGlynn, K A

    2012-08-01

    Germ cell tumours (GCTs) most often arise in the gonads, but some develop extragonadally. The aim of this study was to examine gender- and race-specific trends in incidence and survival of gonadal (GGCTs) and extragonadal GCTs (EGCTs) in the US from 1973 to 2007. We also examined the topographical distribution of EGCTs by race and gender. We estimated age-specific and age-standardized incidence rates and 5-year relative survival rates (RSR) of GCTs using the Surveillance, Epidemiology and End Results (SEER) Program (SEER nine registries). GCTs and their topographical sites were identified using ICD-O morphology and topography codes. Of 21,170 GCTs among males, 5.7% were extragonadal (Whites 5.5%; Blacks 16.3%). Of 2093 GCTs among females, 39.3% were extragonadal (Whites, 36.9%; Blacks 51.0%). The incidence of GGCT was much higher among White (56.3/1,000,000) than Black males (10.0/1,000,000), while there was no difference in incidence between White and Black females (3.2/1,000,000). The rates of EGCT among men and women of both races were similar (range:1.9-3.4/1,000,000). The most frequent extragonadal sites were mediastinum among males and placenta among females. The 5-year RSR of testicular GCT was higher among Whites (97%) than Blacks (90%), as was the 5-year RSR of ovarian GCT (Whites, 92%; Blacks 85%). In general, the 5-year RSRs of EGCTs were lower than the 5-year RSRs of GGCTs. The different incidence trends of GGCTs and EGCTs and distinct age-specific incidence patterns by anatomical site of EGCTs suggest that GGCTs and EGCTs may have different aetiologies.

  14. Search for genes involved in the temperature-induced gonadal sex differentiation in the tilapia, Oreochromis niloticus.

    PubMed

    D'Cotta, H; Fostier, A; Guiguen, Y; Govoroun, M; Baroiller, J F

    2001-11-01

    In the tilapia, Oreochromis niloticus, sex is determined by genetic factors (XX/XY) but temperature can also influence the gonadal sex differentiation. Elevated temperatures of 35 degrees C can generate functional male phenotypes if applied before and during sexual differentiation. The genes and mechanisms by which temperature acts on the cascade leading to sex differentiation have been investigated. Two strategies have been followed: 1) Search for novel genes by differential display, and 2) Expression studies of candidate genes. Genetically all-female and all-male progenies were reared at 27 degrees C (natural temperature) and at 35 degrees C (masculinizing treatment) and gonads dissected. Using differential display, we isolated a 300 bp cDNA (MM20C) from temperature-masculinized females. Virtual northern analysis revealed a 1.2 kb transcript in 35 degrees C treated females and males, but hardly any expression in natural females (27 degrees C). Semi-quantitative RT-PCR established a several-fold increase in MM20C expression in 35 degrees C masculinized fry. Elevated expression was observed in natural males (27 degrees C) with higher levels detected in those reared at 35 degrees C. Furthermore, we have analyzed as a candidate gene the P450 11beta-hydroxylase, an important androgen steroidogenic enzyme. Low levels of expression were found in natural males. This coincides with low concentrations of 11 ketotestosterone in the gonads before and during gonadal sex differentiation. Higher expression levels of 11beta-hydroxylase were detected in male gonads at 35 degrees C but levels in phenotypic males were similar to those found for natural females. Previous results reported that expression of aromatase is repressed by masculinizing treatments. Our study demonstrated that masculinizing-temperature can also stimulate the expression of other gene(s).

  15. Morphometric and histopathological parameters of gonadal development in adult common carp from contaminated and reference sites in Lake Mead, Nevada

    USGS Publications Warehouse

    Patino, R.; Goodbred, S.L.; Draugelis-Dale, R.; Barry, C.E.; Scott, Foott J.; Wainscott, M.R.; Gross, T.S.; Covay, K.J.

    2003-01-01

    This study examined the hypothesis that exposure to sublethal concentrations of contaminants alters the gonadal condition of feral common carp Cyprinus carpio. Adult common carp in Lake Mead, Nevada, were collected from a contaminated site (Las Vegas Bay) that receives municipal and industrial effluent and from a reference site (Overton Arm) with a relatively low level of contamination. Fish were sampled seven times over a 1-year period extending over two separate spawning seasons. Morphometric and histopathological parameters of gonadal and germ cell development were determined. In males, the pattern of seasonal changes in the gonadosomatic index (GSI) was similar between the sites and showed no clear association with site-specific seasonal temperature profiles. However, Las Vegas Bay males had consistently lower GSI values and, on one of the sampling dates, a lower proportion of sperm relative to other germ cell stages (determined histologically). Further, Las Vegas Bay males had a higher incidence of gonadal macrophage aggregates, which are putative tissue biomarkers of contaminant exposure in fishes. In females, seasonal GSI profiles, the frequency of fish with postovulatory follicles (an index of spawning activity), and the timing of new follicle recruitment all showed differences between sites, but these differences generally matched differences in water temperature profile. Also, the peak size-frequency of full-grown follicles did not differ between sites, and estimates of fecundity for the second spawning season indicated that females from the reference site unexpectedly produced a lower number of gametes, Overall, site differences in gonadal condition were observed in carp of both sexes but they seemed to be associated with site differences in contaminant levels only in males. The apparent lack of association between contaminant level and gonadal condition in female carp from mildly mesotrophic Lake Mead may indicate a lack of contaminant effects in

  16. Dose-dependent compensation responses of the hypothalamic-pituitary-gonadal-liver axis of zebrafish exposed to the fungicide prochloraz.

    PubMed

    Dang, Yao; Giesy, John P; Wang, Jianghua; Liu, Chunsheng

    2015-03-01

    Compensation responses and adaptability of hypothalamic-pituitary-gonadal (HPG) axis have been reported in fish exposed to model chemicals, however due to its importance in predictive toxicology further study was needed to elucidate details of the integrated responses to model chemicals. Transcriptional profiles of the hypothalamic-pituitary-gonadal (HPG) axis and concentrations of 17β-estradiol (E2) in plasma were measured in male and female zebrafish that had been exposed to one of seven concentrations of the fungicide, prochloraz: low (1, 3 or 10μg/L), medium (30 or 100μg/L) or high concentrations (300 or 1000μg/L) for 4 days. In zebrafish exposed to the low and medium concentrations of prochloraz, compensation responses of the HPG axis through transcription, occurred in brain (up-regulation of gnrh, gnrhr and lhβ) and both brain and gonad (up-regulation of steroidogenic genes), respectively. Concentrations of E2 in plasma and expression of estrogen receptor 1 (er1) and vitellogenins (vtgs) in liver did not change. This result suggested that compensatory responses were successful in maintaining homeostasis. In zebrafish exposed to the two greatest concentrations, compensatory responses occurred in brain, gonad and liver through up-regulation of er2β, but it failed to maintain concentration of E2 in blood plasma and expression of er1 and vtgs in liver. Collectedly, the results observed in this study allowed characterization of dose-dependent compensatory responses along the HPG axis and liver and identified key linkages between compensatory responses occurring in brain, gonad and liver after exposure to prochloraz.

  17. Transcription of key genes regulating gonadal steroidogenesis in control and ketoconazole- or vinclozolin-exposed fathead minnows.

    PubMed

    Villeneuve, Daniel L; Blake, Lindsey S; Brodin, Jeffrey D; Greene, Katie J; Knoebl, Iris; Miracle, Ann L; Martinovic, Dalma; Ankley, Gerald T

    2007-08-01

    This study evaluated changes in the expression of steroidogenesis-related genes in male fathead minnows exposed to ketoconazole (KTC) or vinclozolin (VZ) for 21 days. The aim was to evaluate links between molecular changes and higher level outcomes after exposure to endocrine-active chemicals (EACs) with different modes of action. To aid our analysis and interpretation of EAC-related effects, we first examined variation in the relative abundance of steroidogenesis-related gene transcripts in the gonads of male and female fathead minnows as a function of age, gonad development, and spawning status, independent of EAC exposure. Gonadal expression of several genes varied with age and/or gonadal somatic index in either males or females. However, with the exception of aromatase, steroidogenesis-related gene expression did not vary with spawning status. Following the baseline experiments, expression of the selected genes in male fathead minnows exposed to KTC or VZ was evaluated in the context of effects observed at higher levels of organization. Exposure to KTC elicited changes in gene transcription that were consistent with an apparent compensatory response to the chemical's anticipated direct inhibition of steroidogenic enzyme activity. Exposure to VZ, an antiandrogen expected to indirectly impact steroidogenesis, increased pituitary expression of follicle-stimulating hormone beta-subunit as well as testis expression of 20beta-hydroxysteroid dehydrogenase and luteinizing hormone receptor transcripts. Results of this study contribute to ongoing research aimed at understanding responses of the teleost hypothalamic-pituitary-gonadal axis to different types of EACs and how changes in molecular endpoints translate into apical outcomes reflective of either adverse effect or compensation.

  18. Dose-dependent compensation responses of the hypothalamic-pituitary-gonadal-liver axis of zebrafish exposed to the fungicide prochloraz.

    PubMed

    Dang, Yao; Giesy, John P; Wang, Jianghua; Liu, Chunsheng

    2015-03-01

    Compensation responses and adaptability of hypothalamic-pituitary-gonadal (HPG) axis have been reported in fish exposed to model chemicals, however due to its importance in predictive toxicology further study was needed to elucidate details of the integrated responses to model chemicals. Transcriptional profiles of the hypothalamic-pituitary-gonadal (HPG) axis and concentrations of 17β-estradiol (E2) in plasma were measured in male and female zebrafish that had been exposed to one of seven concentrations of the fungicide, prochloraz: low (1, 3 or 10μg/L), medium (30 or 100μg/L) or high concentrations (300 or 1000μg/L) for 4 days. In zebrafish exposed to the low and medium concentrations of prochloraz, compensation responses of the HPG axis through transcription, occurred in brain (up-regulation of gnrh, gnrhr and lhβ) and both brain and gonad (up-regulation of steroidogenic genes), respectively. Concentrations of E2 in plasma and expression of estrogen receptor 1 (er1) and vitellogenins (vtgs) in liver did not change. This result suggested that compensatory responses were successful in maintaining homeostasis. In zebrafish exposed to the two greatest concentrations, compensatory responses occurred in brain, gonad and liver through up-regulation of er2β, but it failed to maintain concentration of E2 in blood plasma and expression of er1 and vtgs in liver. Collectedly, the results observed in this study allowed characterization of dose-dependent compensatory responses along the HPG axis and liver and identified key linkages between compensatory responses occurring in brain, gonad and liver after exposure to prochloraz. PMID:25625521

  19. Transcription of key genes regulating gonadal steroidogenesis in control and ketoconazole- or vinclozolin-exposed fathead minnows

    SciTech Connect

    Villeneuve, Daniel L.; Blake, Lindsey S.; Brodin, Jeffrey; Greene, Katie J.; Knoebl, Iris; Miracle, Ann L.; Martinovic, Dalma; Ankley, Gerald T.

    2007-08-01

    This study evaluated changes in the expression of steroidogenesis-related genes in male fathead minnows exposed to ketoconazole (KTC) or vinclozolin (VZ) for 21 days. The aim was to evaluate links between molecular changes and higher level outcomes after exposure to endocrine-active chemicals (EACs) with different modes of action. To aid our analysis and interpretation of EAC-related effects, we first examined variation in the relative abundance of steroidogenesis-related gene transcripts in the gonads of male and female fathead minnows as a function of age, gonad development, and spawning status, independent of EAC exposure. Gonadal expression of several genes varied with age and/or gonadal somatic index in either males or females. However, with the exception of aromatase, steroidogenesis-related gene expression did not vary with spawning status. Following the baseline experiments, expression of the selected genes in male fathead minnows exposed to KTC or VZ was evaluated in the context of effects observed at higher levels of organization. Exposure to KTC elicited changes in gene transcription that were consistent with an apparent compensatory response to the chemical's anticipated direct inhibition of steroidogenic enzyme activity. Exposure to VZ, an antiandrogen expected to indirectly impact steroidogenesis, increased pituitary expression of follicle-stimulating hormone beta-subunit as well as testis expression of 20beta-hydroxysteroid dehydrogenase and luteinizing hormone receptor transcripts. Results of this study contribute to ongoing research aimed at understanding responses of the teleost hypothalamic-pituitary-gonadal axis to different types of EACs and how changes in molecular endpoints translate into apical outcomes reflective of either adverse effect or compensation.

  20. Phenotypic correlations of somatic and gonad traits of sea urchins Glyptocidaris crenularis in two sampled periods: first insight into its breeding and aquaculture

    NASA Astrophysics Data System (ADS)

    Luo, Shibin; Tian, Xiaofei; Zhao, Chong; Zhou, Haisen; Zhang, Weijie; Feng, Wenping; Chang, Yaqing

    2014-03-01

    Prior knowledge of the correlations among commercially important traits in Glyptocidaris crenularis can be used to guide development of breeding and aquaculture programs for this species. We evaluated the phenotypic correlations between somatic and gonadal traits in G. crenularis during two sample periods (October 2010 and April 2011). The coefficients of variation (CV%) for body weight (BW), redness ( a*), yellowness ( b*), gonad wet weight (GW), and gonad index (GI) were >20% in both periods, while those of other traits were very low. GW was significantly correlated with somatic traits (diameter, height, and body weight) in both periods, although the correlation coefficients ranged from 0.473 to 0.636 ( P <0.01). Gonad moisture content (GC), a*, and lightness ( L*) were not significantly correlated with somatic traits ( P >0.05). The color trait b* was negatively correlated with somatic traits (test diameter, test height, and body weight) during the period when the gonads were well developed (April 2011, P <0.05). We observed little difference in the nature of the phenotypic correlations between the two sample periods. The high variation in the somatic and gonad weight traits in G. crenularis suggests there is considerable potential for selective breeding. However, our results suggest that gonad quality traits cannot be selected indirectly by selecting for body weight. Our study provides an insight into the method for improving the breeding and aquaculture of G. crenulari.

  1. Epigenetic Control of Gonadal Aromatase (cyp19a1) in Temperature-Dependent Sex Determination of Red-Eared Slider Turtles

    PubMed Central

    Matsumoto, Yuiko; Buemio, Alvin; Chu, Randy; Vafaee, Mozhgon; Crews, David

    2013-01-01

    In the red-eared slider turtle (Trachemys scripta), a species with temperature-dependent sex determination (TSD), the expression of the aromatase gene during gonad development is strictly limited to the female-producing temperature. The underlying mechanism remains unknown. In this study, we identified the upstream 5′-flanking region of the aromatase gene, gonad-specific promoter, and the temperature-dependent DNA methylation signatures during gonad development in the red-eared slider turtle. The 5′-flanking region of the slider aromatase exhibited sequence similarities to the aromatase genes of the American alligator, chicken, quail, and zebra finch. A putative TATA box was located 31 bp upstream of the gonad-specific transcription start site. DNA methylation at the CpG sites between the putative binding sites of the fork head domain factor (FOX) and vertebrate steroidogenic factor 1 (SF1) and adjacent TATA box in the promoter region were significantly lower in embryonic gonads at the female-producing temperature compared the male-producing temperature. A shift from male- to female-, but not from female- to male-, producing temperature changed the level of DNA methylation in gonads. Taken together these results indicate that the temperature, particularly female-producing temperature, allows demethylation at the specific CpG sites of the promoter region which leads the temperature-specific expression of aromatase during gonad development. PMID:23762231

  2. The basement membrane and the sex establishment in the juvenile hermaphroditism during gonadal differentiation of the Gymnocorymbus ternetzi (Teleostei: Characiformes: Characidae).

    PubMed

    Mazzoni, Talita Sarah; Grier, Harry J; Quagio-Grassiotto, Irani

    2015-12-01

    Although there are several studies on morphogenesis in Teleostei, until now there is no research describing the role of the basement membrane in the establishment of the germinal epithelium during gonadal differentiation in Characiformes. In attempt to study these events that result in the formation of ovarian and testicular structures, gonads of Gymnocorymbus ternetzi were prepared for light microscopy. During gonadal development in G. ternetzi, all individuals first developed ovarian tissue. The undifferentiated gonad was formed by somatic cells (SC) and primordial germ cells (PGCs). After successive mitosis, the PGCs became oogonia, which entered into meiosis originating oocytes. An interstitial tissue developed. In half of the individuals, presumptive female, prefollicle cells synthesized a basement membrane around oocyte forming a follicle. Along the ventral region of the ovary, the tissue invaginated to form the ovigerous lamellae, bordered by the germinal epithelium. Stroma developed and the follicle complexes were formed. The gonadal aromatase was detected in interstitial cells in the early steps of the gonadal differentiation in both sexes. In another half of the individuals, presumptive male, there was no synthesis of basement membrane. The interstitium was invaded by numerous granulocytes. Pre-Leydig cells proliferated. Apoptotic oocytes were observed and afterward degenerated. Spermatogonia appeared near the degenerating oocytes and associated to SCs, forming testicular tubules. Germinal epithelium developed and the basement membrane was synthesized. Concomitantly, there was decrease of the gonadal aromatase and increase in the 3β-HSD enzyme expression. Thus, the testis was organized on an ovary previously developed, constituting an indirect gonochoristic differentiation.

  3. Gonadal Steroid Modulation of Sleep and Wakefulness in Male and Female Rats Is Sexually Differentiated and Neonatally Organized by Steroid Exposure

    PubMed Central

    Hadjimarkou, Maria M.; Mong, Jessica A.

    2014-01-01

    The paucity of clinical and preclinical studies investigating sex differences in sleep has resulted in mixed findings as to the exact nature of these differences. Although gonadal steroids are known to modulate sleep in females, less is known about males. Moreover, little evidence exists concerning the origin of these sex differences in sleep behavior. Thus, the goal of this study was to directly compare the sensitivity of sleep behavior in male and female Sprague Dawley rats to changes in the gonadal steroid milieu and to test whether the sex differences in sleep are the result of brain sexual differentiation or differences in circulating gonadal steroids. Here we report the magnitude of change in sleep behavior induced by either estradiol (E2) or testosterone (T) was greater in females compared with males, suggesting that sleep behavior in females is more sensitive to the suppressive effects of gonadal steroids. Furthermore, we demonstrated that the organizational effects of early gonadal steroid exposure result in male-like responsivity to gonadal steroids and directly alter the activity of the ventrolateral preoptic area (VLPO), an established sleep-promoting nucleus, in adult masculinized females. Moreover, the nonaromatizable androgen dihydrotestosterone did not suppress sleep in either males or females, suggesting that the T-mediated effect in females was due to the aromatization of T into E2. Together our data suggest that, like sex behavior, sex differences in sleep follow the classical organizational/activational effects of gonadal steroids. PMID:24189140

  4. Differentiation and morphogenesis of the ovary and expression of gonadal development-related genes in the protogynous hermaphroditic ricefield eel Monopterus albus.

    PubMed

    He, Z; Li, Y; Wu, Y; Shi, S; Sun, C; Deng, Q; Xie, J; Wang, T; Zhang, W; Zhang, L

    2014-11-01

    The ovarian differentiation, morphogenesis and expression of some putative gonadal development-related genes were analysed in the ricefield eel Monopterus albus, a protogynous hermaphroditic teleost with a single elongate ovary. At c. 1 day post-hatching (dph), the gonadal ridge was colonized with primordial germ cells (PGCs) at the periphery and transformed into the gonadal primordium, which appeared to contain two germinal epithelia. At c. 7 dph, four ovarian cavities appeared in the gonadal tissue with two in each germinal epithelial compartment, and the indifferent gonad might have begun to differentiate into the ovary. The oocytes at the leptotene stage in meiosis I appeared at c. 14 dph, and oocytes at the diplotene stage at c. 30 dph. As development proceeded, the connective tissue separating the two germinal epithelia disappeared, and two of the four ovarian cavities collapsed into one. At 60 dph, the gonad had already taken the shape as observed in the adults. One outer and two inner ovarian cavities could be easily recognized, with slightly basophilic primary growth oocytes usually residing close to the outer ovarian cavity. The expression of cyp19a1a and erb in the early gonad was detected at 6 dph. The abundant expression of foxl2 coincided with the up-regulation of cyp19a1a at 8 dph onwards. The expression of dmrt1 isoforms was not detectable until 8 dph for dmrt1a and dmrt1b and until 33 dph for dmrt1d. The earlier appearance of cyp19a1a compared to dmrt1 transcripts in the indifferent gonad may contribute to the initial differentiation of the gonad towards the ovary in M. albus. PMID:25123578

  5. A specific role for PRND in goat foetal Leydig cells is suggested by prion family gene expression during gonad development in goats and mice.

    PubMed

    Allais-Bonnet, Aurélie; Castille, Johan; Pannetier, Maëlle; Passet, Bruno; Elzaïat, Maëva; André, Marjolaine; Montazer-Torbati, Fatemeh; Moazami-Goudarzi, Katayoun; Vilotte, Jean-Luc; Pailhoux, Eric

    2016-01-01

    Three genes of the prion protein gene family are expressed in gonads. Comparative analyses of their expression patterns in mice and goats revealed constant expression of PRNP and SPRN in both species and in both male and female gonads, but with a weaker expression of SPRN. By contrast, expression of PRND was found to be sex-dimorphic, in agreement with its role in spermatogenesis. More importantly, our study revealed that PRND seems to be a key marker of foetal Leydig cells specifically in goats, suggesting a yet unknown role for its encoded protein Doppel during gonadal differentiation in nonrodent mammals.

  6. Assessment of genotoxicity in gonads, liver and gills of zebrafish (Danio rerio) by use of the comet assay and micronucleus test after in vivo exposure to methyl methanesulfonate.

    PubMed

    Faßbender, Christopher; Braunbeck, Thomas

    2013-07-01

    Since generative tissues are a link between the generations, the detection of genetic damage in testis and ovary of fish is conductive to elucidating the relationship between genotoxicity and impairment of reproduction. In the current study, exposure of zebrafish to methyl methanesulfonate over two weeks caused concentration dependent genotoxic effects in gonads, liver and gills using the alkaline comet assay. Likewise, the micronucleus frequency was elevated in all of these organs. Thus, the comet assay and the micronucleus test proved appropriate for the detection of genotoxicity in primary male and female gonad cells and histological sections of the gonads from zebrafish, respectively.

  7. Mixed gonadal dysgenesis with Turner`s phenotype and mosaic karyotype

    SciTech Connect

    Tarim, O.; Lieber, E. |

    1994-09-01

    A 14 8/12-year-old white female patient was evaluated for short stature and amenorrhea. The past and family history were unremarkable. The physical examination revealed a short girl (131.4 cm; height age: 9) with a weight of 39.5kg (weight age: 11-6/12). The blood pressure was in the normal range in all four extremities and the peripheral pulses were positive. She had stigmata of Turner`s syndrome including short neck and slight webbing, cubitus valgus, and shield chest. There was no heart murmur. The only pubertal sign was pubic hair of Tanner stage II. The chromosome study showed a mosaic pattern. A total of 67 cultured lymphocytes from peripheral blood were analyzed which revealed 13 cells with 45,XO; 14 with 46,XY,r(Y); 39 with 46,XY. The patient had a normal vagina and hypoplastic uterus by sonogram. The diagnosis of mixed gonadal dysgenesis was confirmed by exploratory laparotomy and bilateral gonadectomy. The histologic examination of the gonads showed a testicle on the left and a streak ovary on right. The karyotype of the testicular tissue revealed 45,XO in 32 out of 40 and 46,XY in the remaining 8 cells. Pre-operative hormonal evaluation showed elevated gonadotropin levels of FSH 73.5 and LH 12.5 mIU/ml, low estradiol level of 5 pg/ml, normal testosterone level of 18 and DHEA-S of 181 mcg/dl, and normal thyroid function test with T4 of 6 mcg/dl and TSH of 4.2 mIU/ml. Her bone age was 12 years. The patient was also found to have subnormal growth hormone (GH) secretion by overnight GH study (1.55 ng/ml), clonidine stimulation test (7.3ng/ml), and insulin stimulation test (9.2 ng/ml). She responded well to human synthetic GH treatment with a growth velocity of 11.5 cm in two years. Replacement of sex hormones will be initiated after the completion of growth.

  8. The development of the hypothalamic-pituitary-gonadal axis in juvenile great tits.

    PubMed

    Silverin, B; Sharp, P

    1996-08-01

    The development of the hypolamic-pituitary-gonadal axis in free-living nestling great tits (Parus major) was studied from the day of hatching until about 40 days of age. The hypothalamic content of GnRH was low during the entire nestling period, although a significant increase was noted between 6 and 9 days of age. Thereafter there was no further increase. The pituitary content of LH was low in 1- to 6-day-old nestlings, but increased significantly at 9 days of age; this increase was only temporary, and levels decreased in 12-day-old nestlings. Injections of chicken GnRH increased plasma levels of LH in newly hatched great tits. The high plasma levels of LH in newly hatched great tits of both sexes decreased to basal by 9 days of age. Circulating levels of testosterone and estradiol showed more or less the same pattern as LH. Both steroids showed very high levels in newly hatched birds of both sexes. Testosterone levels were down to basal in 3-day-old nestlings, and estradiol levels were basal in 2-day-old nestlings. The only sex difference was observed in 1- and 2-day-old nestlings. During this period males had significantly higher plasma levels of testosterone than females. Gonads showed a more or less linear growth during the entire nestling period, and did not increase further after fledging. Histological and ultrastructural examinations of the testis showed that mature Leydig cells appeared for the first time in 6-day-old birds and become common in 9-day-old nestlings. The development of the seminiferous tubules, the interstitial tissue, and the tunica albuginea reached a "plateau" when the nestlings had reached an age of 9 days. At no age had the germinal epithelium developed beyond the stage of spermatogonia. GnRH treatment did not change male testosterone or female estradiol levels until the nestlings were 9 days of age. The response decreased in older nestlings. Castration of 9-day-old male nestlings showed that neither was there a negative feedback of

  9. Female gonadal hormones and reproductive behaviors as key determinants of successful reproductive output of breeding whooping cranes (Grus americana).

    PubMed

    Brown, Megan E; Converse, Sarah J; Chandler, Jane N; Shafer, Charles; Brown, Janine L; Keefer, Carol L; Songsasen, Nucharin

    2016-05-01

    Reproductive success of endangered whooping cranes (Grus americana) maintained ex situ is poor. As part of an effort to identify potential causes of poor reproductive success in a captive colony, we used non-invasive endocrine monitoring to assess gonadal and adrenal steroids of bird pairs with various reproductive outcomes and evaluated the relationships of hormones and behaviors to reproductive performance. Overall, reproductively successful (i.e., egg laying) females had significantly higher mean estrogen levels but lower mean progestogen concentrations than did unsuccessful females. Other hormones, including glucocorticoids and androgens, were not significantly different between successful and unsuccessful individuals. Observations of specific behaviors such as unison calling, marching, and the number of copulation attempts, along with overall time spent performing reproductive behaviors, were significantly higher in successful pairs. Our findings indicate that overall reproductive performance of whooping crane pairs is linked to female gonadal hormone excretion and reproductive behaviors, but not to altered adrenal hormone production.

  10. Gonadal histopathology following nickel intoxication in the giant gaurami Colisa fasciatus (Bloch and Schneider), a freshwater tropical perch

    SciTech Connect

    Nath, K.; Kumar, N. )

    1990-08-01

    Large variety of data regarding toxic effects of nickel on mammals has been reported. Nickel refinery workers had increased mortality from lung or sinonasal cancers. In human populations exposed to nickel and chromium compounds, chromosomal abberations have been reported. Biochemical as well as histopathological alterations arising from nickel exposure in mammals have also been documented. Very scanty data is available concerning histopathological impact of nickel on fish tissues. However, to the authors' knowledge, there are no reports available on the fish gonads of either sex encountered with nickel. The present study appears to be the first report on the topic. Therefore, in the present investigation impact of nickel on the histological architecture of gonads of both sexes of a freshwater tropical perch, Colisa fasciatus have been assessed.

  11. Effects of repeated morphine administration on copulation and on the hypothalamic-pituitary-gonadal axis of male rats.

    PubMed

    Tokunaga, Y; Muraki, T; Hosoya, E

    1977-02-01

    Adult male rats were administered morphine twice a day for 45 days and the effects of morphine on the copulation rate, the weight of various organs, and on the hypothalamic-pituitary-gonadal axis were examined. Morphine administered rats showed a loss of weight, hypertrophy of the adrenals, decreased weight of accessory sex organs, low sperm count, and decreased copulation rate. The contents of the luteinizing hormone releasing hormone in the hypothalamus and the luteinizing hormone in the pituitary remained unchanged. Serum luteinizing hormone and testosterone levels decreased, but serum follicle-stimulating hormone levels increased. These results suggest that morphine inhibits the hypothalamic-pituitary-gonadal axis and causes a diminution in the number of fertilizations of the partner females.

  12. Luteinizing hormone and follicle stimulating hormone-releasing hormone test in patients with hypothalamic-pituitary-gonadal dysfunction.

    PubMed

    Mortimer, C H; Besser, G M; McNeilly, A S; Marshall, J C; Harsoulis, P; Tunbridge, W M; Gomez-Pan, A; Hall, R

    1973-10-13

    A standard intravenous 100 mug luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH) test was used to assess the pituitary gonadotrophin responses in 155 patients with a variety of diseases of the hypothalamic-pituitary-gonadal axis. In all but nine patients there was an increase in circulating levels of either LH or FSH in response to the releasing hormone though 137 (88%) were clinically hypogonadal. It was not possible with this test to distinguish between hypothalamic and pituitary causes of hypogonadotrophic hypogonadism, since a variety of LH and FSH responses emerged within the disease groups. However, primary gonadal failure characteristically resulted in exaggerated gonadotrophin response. The potential therapeutic use of the gonadotrophin releasing decapeptide is suggested in certain patients with hypogonadotrophic hypogonadism.

  13. Uptake of benzo(a)pyrene by gonadal tissue of flatfish (family pleuronectidae) and its effects on subsequent egg development

    SciTech Connect

    Hose, J.E.; Hannah, J.B.; Landolt, M.L.; Miller, B.S.; Felton, S.P.; Iwaoka, W.T.

    1981-06-01

    Accumulation of benzo(a)pyrene (BaP) by sexually mature flatfish gonad, its transfer to developing gametes, and its subsequent effects on developing embryos were studied. Thin-layer chromatography revealed both unmetabolized BaP and polar metabolites in the ovary, wolffian ducts, oocytes, and semen of English sole 24 h after ip injection with 200 ..mu..Ci 1/sup 3/H)BaP. Concentrations of BaP and its metabolites were 3 to 11 times higher in oocytes and semen than in gonadal tissue. Fertilized eggs from flathead sole that had been fed 4.0 mg BaP 5 h before spawning demonstrated a significantly lower (p <0.001) hatching success (11.9%) than eggs from control fish (56.6%). Morphological abnormalities were found in only 1.6% of control embryos but in 5.6% of embryos from treated females.

  14. Female gonadal hormones and reproductive behaviors as key determinants of successful reproductive output of breeding whooping cranes (Grus americana)

    USGS Publications Warehouse

    Brown, Megan E; Converse, Sarah J.; Chandler, Jane N.; Shafer, Charles; Brown, Janine L; Keefer, Carol L; Songsasen, Nucharin

    2016-01-01

    Reproductive success of endangered whooping cranes (Grus americana) maintained ex situ is poor. As part of an effort to identify potential causes of poor reproductive success in a captive colony, we used non-invasive endocrine monitoring to assess gonadal and adrenal steroids of bird pairs with various reproductive outcomes and evaluated the relationships of hormones and behaviors to reproductive performance. Overall, reproductively successful (i.e., egg laying) females had significantly higher mean estrogen levels but lower mean progestogen concentrations than did unsuccessful females. Other hormones, including glucocorticoids and androgens, were not significantly different between successful and unsuccessful individuals. Observations of specific behaviors such as unison calling, marching, and the number of copulation attempts, along with overall time spent performing reproductive behaviors, were significantly higher in successful pairs. Our findings indicate that overall reproductive performance of whooping crane pairs is linked to female gonadal hormone excretion and reproductive behaviors, but not to altered adrenal hormone production.

  15. Female gonadal hormones and reproductive behaviors as key determinants of successful reproductive output of breeding whooping cranes (Grus americana).

    PubMed

    Brown, Megan E; Converse, Sarah J; Chandler, Jane N; Shafer, Charles; Brown, Janine L; Keefer, Carol L; Songsasen, Nucharin

    2016-05-01

    Reproductive success of endangered whooping cranes (Grus americana) maintained ex situ is poor. As part of an effort to identify potential causes of poor reproductive success in a captive colony, we used non-invasive endocrine monitoring to assess gonadal and adrenal steroids of bird pairs with various reproductive outcomes and evaluated the relationships of hormones and behaviors to reproductive performance. Overall, reproductively successful (i.e., egg laying) females had significantly higher mean estrogen levels but lower mean progestogen concentrations than did unsuccessful females. Other hormones, including glucocorticoids and androgens, were not significantly different between successful and unsuccessful individuals. Observations of specific behaviors such as unison calling, marching, and the number of copulation attempts, along with overall time spent performing reproductive behaviors, were significantly higher in successful pairs. Our findings indicate that overall reproductive performance of whooping crane pairs is linked to female gonadal hormone excretion and reproductive behaviors, but not to altered adrenal hormone production. PMID:27080552

  16. Two gonad-infecting species of Philometra (Nematoda: Philometridae) from marine fishes off the northern coast of Australia.

    PubMed

    Moravec, František; Barton, Diane P

    2015-01-01

    Two different gonad-infecting species of Philometra Costa, 1845 were collected from the ovary of marine perciform fishes, the blackspotted croaker Protonibea diacanthus (Sciaenidae) and the John's snapper Lutjanus johnii (Lutjanidae), from off the northern coast of Australia. Nematodes (males and females) from P. diacanthus represent a new taxon, Philometra protonibeae n. sp., which is mainly characterized by the body length of the males (3.37-3. 90 mm), broad, equally long spicules (length 126-141 μm) and the shape and structure of the gubernaculum with a dorsally lamellate distal tip. The nematodes (only females) from L. johnii may represent an undescribed species, but, because of the absence of conspecific males, they could not be specifically identified. Philometra protonibeae is the fifth nominal gonad-infecting species of this genus recorded from marine fishes in Australian waters and the seventh species of these parasites described from fishes of the family Sciaenidae.

  17. Pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamic-pituitary-gonadal axis: a review of the literature.

    PubMed

    Thomas, Robin L; Crawford, Natalie M; Grafer, Constance M; Halvorson, Lisa M

    2013-08-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP), an ancient molecule highly preserved across species, has been classified as a member of the secretin/glucagon/vasoactive intestinal peptide/growth hormone-releasing hormone polypeptide family. PACAP was first identified as a hypothalamic-releasing factor; nevertheless, it has subsequently been determined to have widespread distribution and function, including expression in the pituitary, gonads, placenta, central and peripheral nervous systems, intestinal tract, and adrenal gland. Consistent with its widespread distribution, PACAP has been found to exert pleiotropic effects. Although first described over 20 years ago, only relatively recently has substantial attention turned to evaluating PACAP's role in the reproductive system. This review will focus on our current understanding of the expression pattern and function of PACAP in the hypothalamic-pituitary-gonadal axis.

  18. Laparoscopic transperitoneal gonadal vein ligation for treatment of pelvic congestion secondary to Nutcracker syndrome: a case report.

    PubMed

    Viriyaroj, Vichit; Akranurakkul, Prinya; Muyphuag, Bunlung; Kitporntheranunt, Maethaphan

    2012-12-01

    Nutcracker syndrome is the term used to describe the patient with clinical symptoms of entrapment of the left renal vein between the aorta and the superior mesenteric artery. Pelvic congestion syndrome, which is a cause of chronic pelvic pain in women, may be due to Nutcracker syndrome. There are many modalities of treatment for Nutcracker syndrome. This is a case report of a 32-year old woman with pelvic congestion syndrome due to Nutcracker syndrome, who subsequently underwent laparoscopic transperitoneal left gonadal vein ligation. She has had complete remission of pain in 4 months after the operation and after 12 months of follow-up. Laparoscopic transperitoneal gonadal vein ligation is an approach that is safe, simple and provides good results for patient with pelvic congestion syndrome secondary to Nutcracker syndrome.

  19. Influence of seasonal and environmental patterns on the lipid content and fatty acid profiles in gonads of the edible sea urchin Paracentrotus lividus from Sardinia.

    PubMed

    Siliani, Silvia; Melis, Riccardo; Loi, Barbara; Guala, Ivan; Baroli, Maura; Sanna, Roberta; Uzzau, Sergio; Roggio, Tonina; Addis, Maria Filippa; Anedda, Roberto

    2016-02-01

    The influence of seasonal and environmental patterns on the lipid fraction of Paracentrotus lividus gonads was investigated. For this purpose, sea urchins were collected monthly over a year from two Sardinian coastal areas. Total lipids in gonads follow an annual cyclical trend, described by a sine wave curve, that it is more influenced by season than by growing area. The lowest lipid content in gonads corresponds to a high percentage of mature reproductive stages (i.e. winter season), independently of sampling area. A variation in total lipid content follows a change in photoperiod, while it is related to sea surface temperature. Multivariate analysis on fatty acid profiles of gonads, detected by gas chromatography, clusters the collected specimens mainly according to the sampling area, secondly according to the sites within the same sampling area and finally according to season.

  20. A time-course analysis of effects of the steroidogenesis inhibitor ketoconazole on components of the hypothalamic-pituitary-gonadal axis of fathead minnows (Presentation)

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconazo...

  1. A Time-course Analysis of Effects of the Steroidogenesis Inhibitor Ketoconazole on Components of the Hypothalamic-pituitary-gonadal Axis of Fathead Minnows

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconazo...

  2. Histochemical and immunohistochemical studies of the gonads and paramesonephric ducts of male and female hatchlings of loggerhead sea turtles (Caretta caretta).

    PubMed

    Sarı, F; Kaska, Y

    2016-08-01

    The sex of neonatal sea turtles is difficult to determine, because neonates lack heteromorphic sex chromosomes and dimorphic external characteristics; internal dimorphic morphology is defined at hatching. We used histochemical staining and made measurements in the gonads and paramesonephric ducts (PD) of both sexes to determine structural differences in female and male loggerhead sea turtle (Caretta caretta) hatchlings. We detected differences in the gonads and PD between the sexes including the amounts of mucopolysaccharides, collagen and elastic fibers. We determined that the thickness of the gonadal cortex and the diameter of the PD lumen are reliable sex-specific characteristics. We also assessed immunolocalization of aromatase, an enzyme complex that converts androgens to estrogens, and found differences in the localization and intensity of aromatase immunostaining in the gonads and PD of female and male hatchlings. Comprehensive studies of the sexual differences of sea turtles are important for conservation programs. PMID:27437606

  3. Transcriptional regulatory dynamics of the hypothalamic-pituitary-gonadal axis and its peripheral pathways as impacted by the 3-beta HSD inhibitor Trilostane in zebrafish (Danio rerio)

    EPA Science Inventory

    To identify transcription factors (TFs), members of hypothalamic-pituitary- gonadal axis (HPG-axis), TF networks and signaling pathways underlying generalized effects of 3-beta hydroxysteroid dehydrogenase (HSD3B) inhibition, reproductively mature zebrafish (Danio rerio) were exp...

  4. Histochemical and immunohistochemical studies of the gonads and paramesonephric ducts of male and female hatchlings of loggerhead sea turtles (Caretta caretta).

    PubMed

    Sarı, F; Kaska, Y

    2016-08-01

    The sex of neonatal sea turtles is difficult to determine, because neonates lack heteromorphic sex chromosomes and dimorphic external characteristics; internal dimorphic morphology is defined at hatching. We used histochemical staining and made measurements in the gonads and paramesonephric ducts (PD) of both sexes to determine structural differences in female and male loggerhead sea turtle (Caretta caretta) hatchlings. We detected differences in the gonads and PD between the sexes including the amounts of mucopolysaccharides, collagen and elastic fibers. We determined that the thickness of the gonadal cortex and the diameter of the PD lumen are reliable sex-specific characteristics. We also assessed immunolocalization of aromatase, an enzyme complex that converts androgens to estrogens, and found differences in the localization and intensity of aromatase immunostaining in the gonads and PD of female and male hatchlings. Comprehensive studies of the sexual differences of sea turtles are important for conservation programs.

  5. A Time-course Analysis of Effects of the Steroidogenesis Inhibitor Ketoconazole on Components of the Hypothalamic-pituitary-gonadal Axis of Fathead Minnows

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconaz...

  6. Wolbachia gonadal density in female and male Drosophila vary with laboratory adaptation and respond differently to physiological and environmental challenges.

    PubMed

    Correa, Claudia C; Ballard, J William O

    2012-11-01

    In symbiotic associations such as those between Wolbachia and insects, the within-host symbiont density plays an important role in the maintenance of the infection in natural populations, as it relates to transmission fidelity and pathogenicity of the symbiont. Within-host density is speculated to be the result of complex interactions between the bacterial genotype, the host genotype and the environment, which may account for the substantial variation in Wolbachia titres among wild collected individuals compared to laboratory lines. Using quantitative PCR, we screened the Wolbachia gonadal density of individuals from 50 isofemale Drosophila simulans lines raised in standard conditions for at least two generations after collection from the wild. Although these newly collected lines displayed significant variation of ovarian Wolbachia titres, such variation was lost by F(19). Assaying these flies at different ages and under different environmental conditions indicated that symbiont titres in female gonads were not affected by the conditions tested. However, Wolbachia density in male gonads was consistently affected by these treatments in a line-specific way. We propose that the differences in Wolbachia densities among ovaries of F(4) flies are the consequence of large differences in the field-collected females caused by the variable environment, and carried over for at least four generations. In addition, we provide evidence of sex-specific dynamics of Wolbachia in gonads of females and males. In combination, our results support the view of sex-specific Wolbachia evolutionary interactions for males and females, which has been predicted by theory and observed experimentally.

  7. Iron excess disturbs metabolic status and relative gonad mass in rats on high fat, fructose, and salt diets.

    PubMed

    Suliburska, Joanna; Bogdański, Paweł; Szulińska, Monika

    2013-02-01

    The aim of this study was to assess the metabolic and physiological changes in rats fed a diet high in fat, fructose, and salt, and with excess iron level. Mineral status was also estimated. Wistar rats were assigned to groups fed either a standard control diet (C) or a diet high in fat, fructose, and salt. The noncontrol diets contained either normal (M) or high level (MFe) of iron. After 6 weeks, the length and weight of the rats were measured, and the animals were euthanized. The kidneys and gonads were collected, and blood samples were taken. Serum levels of insulin, nitric oxide, and iron were measured. The iron, zinc, copper, and calcium concentrations of tissues were determined. It was found that the M diet led to a significant increase in the relative kidney mass of the rats compared with the control group. Among the rats fed the M diet, markedly higher serum level of iron and lower levels of zinc and copper were observed in tissues, while significantly higher calcium levels were found in the gonads. The MFe diet resulted in decreased obesity index, insulin level, and nitric oxide serum concentration in the rats, when compared with both the M and C diets. The high iron level in the modified diet increased the relative mass of the gonads. The excess iron level in the diet disturbed the zinc, copper, and calcium status of tissues. The decrease in insulin and nitric oxide in rats fed the diet high in iron, fat, fructose, and salt was associated with disorders of zinc, copper, and calcium status, as well as with an increase in the relative mass of the gonads.

  8. Loss of DNase II function in the gonad is associated with a higher expression of antimicrobial genes in Caenorhabditis elegans.

    PubMed

    Yu, Hsiang; Lai, Huey-Jen; Lin, Tai-Wei; Chen, Chang-Shi; Lo, Szecheng J

    2015-08-15

    Three waves of apoptosis shape the development of Caenorhabditis elegans. Although the exact roles of the three DNase II genes (nuc-1, crn-6 and crn-7), which are known to mediate degradation of apoptotic DNA, in the embryonic and larval phases of apoptosis have been characterized, the DNase II acting in the third wave of germ cell apoptosis remains undetermined. In the present study, we performed in vitro and in vivo assays on various mutant nematodes to demonstrate that NUC-1 and CRN-7, but not CRN-6, function in germ cell apoptosis. In addition, in situ DNA-break detection and anti-phosphorylated ERK (extracellular-signal-regulated kinase) staining illustrated the sequential and spatially regulated actions of NUC-1 and CRN-7, at the pachytene zone of the gonad and at the loop respectively. In line with the notion that UV-induced DNA fragment accumulation in the gonad activates innate immunity responses, we also found that loss of NUC-1 and CRN-7 lead to up-regulation of antimicrobial genes (abf-2, spp-1, nlp-29, cnc-2, and lys-7). Our observations suggest that an incomplete digestion of DNA fragments resulting from the absence of NUC-1 or CRN-7 in the gonad could induce the ERK signalling, consequently activating antimicrobial gene expression. Taken together, the results of the present study demonstrate for the first time that nuc-1 and crn-7 play a role in degrading apoptotic DNA in distinct sites of the gonad, and act as negative regulators of innate immunity in C. elegans.

  9. Effect of testosterone on the hypothalamic-pituitary-gonadal axis of pinealectomized and pineal-intact male rats.

    PubMed

    Wallen, E P; Turek, F W

    1979-05-15

    Previous studies indicate that steroid hormones alter pineal biochemistry, and it has been suggested that at least part of the negative feedback effect of steroid hormones on pituitary gonadotropin release may be mediated by the pineal gland. In this study, pinealectomy did not alter the inhibitory effect of testosterone on neuroendocine-gonadal activity in the male rat, suggesting that the pineal gland does not mediate the response of the rat hypothalamic-pituitary axis to testosterone.

  10. Effects of 17 α-methyltestosterone on transcriptome, gonadal histology and sex steroid hormones in rare minnow Gobiocypris rarus.

    PubMed

    Gao, Jiancao; Liu, Shaozhen; Zhang, Yingying; Yang, Yanping; Yuan, Cong; Chen, Shu; Wang, Zaizhao

    2015-09-01

    The 17α-methyltestosterone (MT), a synthetic androgen, is known for its interference effects on the endocrine system. Aiming to investigate the transcriptome profiling of gonads induced by MT and to understand the molecular mechanism by which MT causes adverse effects in fish, transcriptome profiling of gonads, gonadal histology and the sex steroid hormones in response to MT were analyzed in Gobiocypris rarus. Eight libraries, 4 from the ovary and 4 from the testis, were constructed and sequenced and then a total number of clean reads per sample ranging from 7.03 to 9.99 million were obtained. In females, a total of 191 transcripts were differentially regulated by MT, consisting of 102 up-regulated transcripts and 89 down-regulated transcripts. In males, 268 differentially expressed genes with 108 up-regulated and 160 down-regulated were detected upon MT exposure. Testosterone serves as the major sex steroid hormone content in G. rarus of both sexes. The concentrations of 17β-estradiol, testosterone and 11-ketotestosterone were significantly increased in females and decreased in males after MT exposure. Interestingly, MT caused a decreased number of vitellogenic oocytes in the ovary and spermatozoa in the testis. After MT exposure, four differentially expressed genes (ndufa4, slc1a3a, caskin-2 and rpt3) were found in G. rarus of both sexes. Overall, we suggest that MT seemed to affect genes involved in pathways related to physiological processes in the gonads of G. rarus. These processes include the electron transfer of Complex IV, endothelial cell activation, axon growth and guidance, and proteasome assembly and glutamate transport metabolic.

  11. In Vivo Administration of Scallop GnRH-Like Peptide Influences on Gonad Development in the Yesso Scallop, Patinopecten yessoensis

    PubMed Central

    Nagasawa, Kazue; Oouchi, Hitoshi; Itoh, Naoki; Takahashi, Keisuke G.; Osada, Makoto

    2015-01-01

    Existing research on the role of gonadotropin-releasing hormone (GnRH) in bivalve reproduction is inadequate, even though a few bivalve GnRH orthologs have been cloned. The objective of this paper was to elucidate the in vivo effect of GnRH administration in Yesso scallop reproduction. We performed in vivo administration of scallop GnRH (py-GnRH) synthetic peptide into the developing gonad, and analyzed its effect on gonad development for 6 weeks during the reproductive season. The resulting sex ratio in the GnRH administered (GnRH(+)) group might be male biased, whereas the control (GnRH(-)) group had an equal sex ratio throughout the experiment. The gonad index (GI) of males in the GnRH(+) group increased from week 2 to 24.8% at week 6. By contrast the GI of the GnRH(-) group peaked in week 4 at 16.6%. No significant difference was seen in female GI between the GnRH(+) and GnRH(-) groups at any sampling point. Oocyte diameter in the GnRH(+) group remained constant (about 42–45 μm) throughout the experiment, while in the GnRH(-) group it increased from 45 to 68 μm i.e. normal oocyte growth. The number of spermatogonia in the germinal acini of males in the GnRH(+) group increased from week 4 to 6. Hermaphrodites appeared in the GnRH(+) group in weeks 2 and 4. Their gonads contained many apoptotic cells including oocytes. In conclusion, this study suggests that py-GnRH administration could have a potential to accelerate spermatogenesis and cause an inhibitory effect on oocyte growth in scallops. PMID:26030928

  12. Ultrastructural changes and programmed cell death of trophocytes in the gonad of Isohypsibius granulifer granulifer Thulin, 1928 (Tardigrada, Eutardigrada, Isohypsibiidae).

    PubMed

    Poprawa, Izabela; Hyra, Marta; Kszuk-Jendrysik, Michalina; Rost-Roszkowska, Magdalena Maria

    2015-03-01

    The studies on the fates of the trophocytes, the apoptosis and autophagy in the gonad of Isohypsibius granulifer granulifer have been described using transmission electron microscope, light and fluorescent microscopes. The results presented here are the first that are connected with the cell death of nurse cells in the gonad of tardigrades. However, here we complete the results presented by Węglarska (1987). The reproductive system of I. g. granulifer contains a single sack-like hermaphroditic gonad and a single gonoduct. The gonad is composed of three parts: a germarium filled with proliferating germ cells (oogonia); a vitellarium that has clusters of female germ cells (the region of oocytes development); and a male part filled with male germ cells in which the sperm cells develop. The trophocytes (nurse cells) show distinct alterations during all of the stages of oogenesis: previtello-, vitello- and choriogenesis. During previtellogenesis the female germ cells situated in the vitellarium are connected by cytoplasmic bridges, and form clusters of cells. No ultrastructural differences appear among the germ cells in a cluster during this stage of oogenesis. In early vitellogenesis, the cells in each cluster start to grow and numerous organelles gradually accumulate in their cytoplasm. However, at the beginning of the middle of vitellogenesis, one cell in each cluster starts to grow in order to differentiate into oocyte, while the remaining cells are trophocytes. Eventually, the cytoplasmic bridges between the oocyte and trophocytes disappear. Autophagosomes also appear in the cytoplasm of nurse cells together with many degenerating organelles. The cytoplasm starts to shrink, which causes the degeneration of the cytoplasmic bridges between trophocytes. Apoptosis begins when the cytoplasm of these cells is full of autophagosomes/autolysosomes and causes their death.

  13. Effects of 17 α-methyltestosterone on transcriptome, gonadal histology and sex steroid hormones in rare minnow Gobiocypris rarus.

    PubMed

    Gao, Jiancao; Liu, Shaozhen; Zhang, Yingying; Yang, Yanping; Yuan, Cong; Chen, Shu; Wang, Zaizhao

    2015-09-01

    The 17α-methyltestosterone (MT), a synthetic androgen, is known for its interference effects on the endocrine system. Aiming to investigate the transcriptome profiling of gonads induced by MT and to understand the molecular mechanism by which MT causes adverse effects in fish, transcriptome profiling of gonads, gonadal histology and the sex steroid hormones in response to MT were analyzed in Gobiocypris rarus. Eight libraries, 4 from the ovary and 4 from the testis, were constructed and sequenced and then a total number of clean reads per sample ranging from 7.03 to 9.99 million were obtained. In females, a total of 191 transcripts were differentially regulated by MT, consisting of 102 up-regulated transcripts and 89 down-regulated transcripts. In males, 268 differentially expressed genes with 108 up-regulated and 160 down-regulated were detected upon MT exposure. Testosterone serves as the major sex steroid hormone content in G. rarus of both sexes. The concentrations of 17β-estradiol, testosterone and 11-ketotestosterone were significantly increased in females and decreased in males after MT exposure. Interestingly, MT caused a decreased number of vitellogenic oocytes in the ovary and spermatozoa in the testis. After MT exposure, four differentially expressed genes (ndufa4, slc1a3a, caskin-2 and rpt3) were found in G. rarus of both sexes. Overall, we suggest that MT seemed to affect genes involved in pathways related to physiological processes in the gonads of G. rarus. These processes include the electron transfer of Complex IV, endothelial cell activation, axon growth and guidance, and proteasome assembly and glutamate transport metabolic. PMID:26070167

  14. Ultrastructural changes and programmed cell death of trophocytes in the gonad of Isohypsibius granulifer granulifer Thulin, 1928 (Tardigrada, Eutardigrada, Isohypsibiidae).

    PubMed

    Poprawa, Izabela; Hyra, Marta; Kszuk-Jendrysik, Michalina; Rost-Roszkowska, Magdalena Maria

    2015-03-01

    The studies on the fates of the trophocytes, the apoptosis and autophagy in the gonad of Isohypsibius granulifer granulifer have been described using transmission electron microscope, light and fluorescent microscopes. The results presented here are the first that are connected with the cell death of nurse cells in the gonad of tardigrades. However, here we complete the results presented by Węglarska (1987). The reproductive system of I. g. granulifer contains a single sack-like hermaphroditic gonad and a single gonoduct. The gonad is composed of three parts: a germarium filled with proliferating germ cells (oogonia); a vitellarium that has clusters of female germ cells (the region of oocytes development); and a male part filled with male germ cells in which the sperm cells develop. The trophocytes (nurse cells) show distinct alterations during all of the stages of oogenesis: previtello-, vitello- and choriogenesis. During previtellogenesis the female germ cells situated in the vitellarium are connected by cytoplasmic bridges, and form clusters of cells. No ultrastructural differences appear among the germ cells in a cluster during this stage of oogenesis. In early vitellogenesis, the cells in each cluster start to grow and numerous organelles gradually accumulate in their cytoplasm. However, at the beginning of the middle of vitellogenesis, one cell in each cluster starts to grow in order to differentiate into oocyte, while the remaining cells are trophocytes. Eventually, the cytoplasmic bridges between the oocyte and trophocytes disappear. Autophagosomes also appear in the cytoplasm of nurse cells together with many degenerating organelles. The cytoplasm starts to shrink, which causes the degeneration of the cytoplasmic bridges between trophocytes. Apoptosis begins when the cytoplasm of these cells is full of autophagosomes/autolysosomes and causes their death. PMID:25543879

  15. Influence of gonadal hormones on the behavioral effects of intermittent hypoxia in mice

    PubMed Central

    Jenkins, Richelle; Magalang, Ulysses J.; Nelson, Randy J.

    2014-01-01

    Obstructive sleep apnea (OSA) is characterized by repetitive upper airway obstruction resulting in cyclic intermittent hypoxia (IH) during sleep in affected individuals. OSA occurs more frequently in postmenopausal than premenopausal women and the severity of OSA increases after menopause. Gonadal hormones can influence brain and behavior; testosterone and estrogens in particular can enhance spatial learning and memory. We hypothesized that estrogens may protect mice from IH-induced hippocampal morphological and behavioral changes. To test this hypothesis we exposed intact or gonadectomized male and female mice to room air or IH [15 cycles/h, 8 h/day, fraction of inspired oxygen (FiO2) nadir of 5%] for a total of 30 days. During the final 4 days of IH, mice were tested for anxiety- and depressive-like behaviors. After cessation of IH exposure mice were tested on the Barnes maze and passive avoidance tests to assess learning and memory. Ovariectomy paired with IH treatment, impaired spatial learning and memory compared to all other female groups. Intact male mice receiving IH treatment also had impaired learning and memory compared with intact or castrated male mice exposed to room air. Learning and memory changes were mirrored by changes in basilar dendritic length of the CA1 region of the hippocampus. These data suggest that estrogens provide protection against IH-induced deficits, whereas androgens partially exacerbate IH-induced deficits on learning and memory. PMID:25552660

  16. Gonadal Hormones Rapidly Enhance Spatial Memory and Increase Hippocampal Spine Density in Male Rats.

    PubMed

    Jacome, Luis F; Barateli, Ketti; Buitrago, Dina; Lema, Franklin; Frankfurt, Maya; Luine, Victoria N

    2016-04-01

    17β-estradiol (E2) rapidly, within minutes, activates behaviors and cognition by binding to membrane estrogen receptors, activating cell signaling cascades and increasing dendritic spines. In female rodents, E2 enhances spatial memory within 2-4 hours, and spine density is increased in the CA1 area of the hippocampus within 30-60 minutes. Although chronic gonadal hormone treatments in male rats alter cognition and spines/spine synapses and acute hormone effects occur in hippocampal slices, effects of acute, in vivo hormone administration in males are unknown. Therefore, we assessed rapid effects of E2 (20 μg/kg) and testosterone (T) (750 μg/kg) on spatial memory using the object placement task and on hippocampal spine density using Golgi impregnation. Orchidectomized rats received hormones immediately after the training trial and were tested for retention 2 hours later. Vehicle-injected orchidectomized males spent equal time exploring objects in the old and new locations, but E2- or T-treated subjects spent more time exploring objects at the new location, suggesting enhanced memory. Both hormones also increased spine density in CA1, but not the dentate gyrus, by 20%-40% at 30 minutes and 2 hours after injections. This report is the first, to our knowledge, to show E2 and T enhancements of memory and spine density within such a short time frame in male rats.

  17. Gonad morphogenesis defects drive hybrid male sterility in asymmetric hybrid breakdown of Caenorhabditis nematodes.

    PubMed

    Dey, Alivia; Jin, Qi; Chen, Yen-Chu; Cutter, Asher D

    2014-01-01

    Determining the causes and evolution of reproductive barriers to gene flow between populations, speciation, is the key to understanding the origin of diversity in nature. Many species manifest hybrid breakdown when they intercross, characterized by increasingly exacerbated problems in later generations of hybrids. Recently, Caenorhabditis nematodes have emerged as a genetic model for studying speciation, and here we investigate the nature and causes of hybrid breakdown between Caenorhabditis remanei and C. latens. We quantify partial F1 hybrid inviability and extensive F2 hybrid inviability; the ~75% F2 embryonic arrest occurs primarily during gastrulation or embryonic elongation. Moreover, F1 hybrid males exhibit Haldane's rule asymmetrically for both sterility and inviability, being strongest when C. remanei serves as maternal parent. We show that the mechanism by which sterile hybrid males are incapable of transferring sperm or a copulatory plug involves defective gonad morphogenesis, which we hypothesize results from linker cell defects in migration and/or cell death during development. This first documented case of partial hybrid male sterility in Caenorhabditis follows expectations of Darwin's corollary to Haldane's rule for asymmetric male fitness, providing a powerful foundation for molecular dissection of intrinsic reproductive barriers and divergence of genetic pathways controlling organ morphogenesis.

  18. Divergence along the gonadal steroidogenic pathway: Implications for hormone-mediated phenotypic evolution.

    PubMed

    Rosvall, Kimberly A; Bergeon Burns, Christine M; Jayaratna, Sonya P; Ketterson, Ellen D

    2016-08-01

    Across a range of taxa, hormones regulate suites of traits that influence survival and reproductive success; however, the mechanisms by which hormone-mediated traits evolve are still unclear. We hypothesized that phenotypic divergence might follow from differential regulation of genes encoding key steps in hormone biosynthesis and thus the rate of hormone production. We tested this hypothesis in relation to the steroid hormone testosterone by comparing two subspecies of junco (Junco hyemalis) in the wild and in captivity. These subspecies have diverged over the last 10-15kyears in multiple testosterone-mediated traits, including aggression, ornamentation, and body size. We show that variation in gonadal gene expression along the steroid biosynthetic pathway predicts phenotypic divergence within and among subspecies, and that the more androgenized subspecies exhibits a more prolonged time-course of elevated testosterone following exogenous stimulation. Our results point to specific genes that fulfill key conditions for phenotypic evolution because they vary functionally in their expression among individuals and between populations, and they map onto population variation in phenotype in a common garden. Our findings therefore build an important bridge between hormones, genes, and phenotypic evolution. PMID:27206546

  19. Effects of early postnatal gonadal steroids on extinction of a continuously food-rewarded running response.

    PubMed

    Enriquez, P; Calés, J M; Sánchez-Santed, F; Guillamón, A

    1991-01-01

    In the present work the existence of sex differences (Experiment 1) on the acquisition and extinction of a continuously reinforced response in a short and narrow runway (100 x 9 x 10 cm) were investigated. In addition to the investigation of the basic sex differences in Experiment 1, the effect of postpuberal gonadectomy of male and female rats and the role of the early postnatal gonadal steroids on these situations were also examined in Experiments 2 and 3, respectively. In all experiments, no sex differences were found in acquisition. However, males extinguished faster than female rats. Gonadectomy of both sexes in adulthood, although it increases their latencies in acquisition, did not affect the differences between sexes during extinction. In contrast, in Experiment 3 female androgenization and male orchidectomy on day one after birth reversed the direction of sex differences found between control rats in the extinction period. Our findings suggests that the observed sex differences in extinction may be due to an underlying sexual dimorphism in the response inhibition process.

  20. Influence of gonadal hormones on the behavioral effects of intermittent hypoxia in mice.

    PubMed

    Aubrecht, Taryn G; Jenkins, Richelle; Magalang, Ulysses J; Nelson, Randy J

    2015-03-15

    Obstructive sleep apnea (OSA) is characterized by repetitive upper airway obstruction resulting in cyclic intermittent hypoxia (IH) during sleep in affected individuals. OSA occurs more frequently in postmenopausal than premenopausal women and the severity of OSA increases after menopause. Gonadal hormones can influence brain and behavior; testosterone and estrogens in particular can enhance spatial learning and memory. We hypothesized that estrogens may protect mice from IH-induced hippocampal morphological and behavioral changes. To test this hypothesis we exposed intact or gonadectomized male and female mice to room air or IH [15 cycles/h, 8 h/day, fraction of inspired oxygen (FiO 2) nadir of 5%] for a total of 30 days. During the final 4 days of IH, mice were tested for anxiety- and depressive-like behaviors. After cessation of IH exposure mice were tested on the Barnes maze and passive avoidance tests to assess learning and memory. Ovariectomy paired with IH treatment, impaired spatial learning and memory compared to all other female groups. Intact male mice receiving IH treatment also had impaired learning and memory compared with intact or castrated male mice exposed to room air. Learning and memory changes were mirrored by changes in basilar dendritic length of the CA1 region of the hippocampus. These data suggest that estrogens provide protection against IH-induced deficits, whereas androgens partially exacerbate IH-induced deficits on learning and memory.

  1. Exercise, Training, and the Hypothalamic-Pituitary-Gonadal Axis in Men and Women.

    PubMed

    Cano Sokoloff, Natalia; Misra, Madhusmita; Ackerman, Kathryn E

    2016-01-01

    The hypothalamic-pituitary-gonadal (HPG) axis is essential for adequate responses to exercise and training both acutely and chronically. Both testosterone and estrogen play leading roles in neuromuscular adaptation to exercise in males and females. The purpose of this chapter is to illustrate the physiological and pathological changes that occur in the HPG axis secondary to exercise and training. In males, testosterone increases with acute bouts of exercise, but long-term effects are less clear, with evidence of lower testosterone in endurance athletes. Restricted energy availability may negatively affect hormone levels in male endurance athletes, but data regarding low energy availability and its impact on the HPG axis are limited in male athletes. Conversely, in females there is significant evidence that decreased energy availability inhibits the HPG axis, leading to menstrual irregularities and lower bone density. Hormonal changes secondary to acute bouts of exercise are more challenging to interpret in females due to menstrual variability, which traditionally has not been taken into account in many studies. However, some evidence supports an increase in testosterone and estradiol with acute exercise. More work is needed to elucidate the relationships among energy availability, basal hormonal fluctuations, and exercise, and their collective effects on the HPG axis.

  2. Effects of exogenous and endogenous opiates on the hypothalamic--pituitary--gonadal axis in the male.

    PubMed

    Cicero, T J

    1980-06-01

    Narcotics acutely depress serum testosterone levels in the male. Three mechanisms could be involved: an enhancement of the degradation of testosterone; a direct inhibition of testicular steroidogenesis; or, finally, an inhibition of the hypothalamic-pituitary-luteinizing hormone (LH) axis resulting in a reduction in LH-dependent testicular steroidogenesis. The currently available evidence indicates that narcotics do not affect the catabolism of testosterone by the liver or testicular steroidogenesis. Rather, the data favor a direct action on the hypothalamic--pituitary--LH axis, probably by inhibiting the secretion of LH-releasing hormone (LH-RH) from the hypothalamus. The effects of narcotics on serum LH appear to be mediated via specific opioid receptors, suggesting that a naturally occurring opioid-like substance exists that normally inhibits LH. In support of this conclusion, opiate receptor blockers markedly increase serum LH levels shortly after their subcutaneous administration. In addition, endogenous opioids also seem to participate in testosterone's negative feedback control of the hypothalamic--pituitary--LH axis. Thus, it appears that opiate drugs inhibit the function of the hypothalamic-pituitary-gonadal axis by occupying opiate receptors in the hypothalamus and, moreover, that endogenous opioids exist that normally bind to these receptors and regulate activity in this axis.

  3. Acute re-feeding reverses food restriction-induced hypothalamic-pituitary-gonadal axis deficits.

    PubMed

    Temple, J L; Rissman, E F

    2000-12-01

    Undernutrition has well-established effects on female reproduction. Here we describe the effects of food restriction on aspects of the hypothalamic-pituitary-gonadal (HPG) axis in the female musk shrew. We determined that acute re-feeding reverses deficits brought on by food restriction. Two days of food restriction led to an increase in proGnRH immunoreactive cells in the preoptic area relative to ad libitum-fed controls (AL). This increase was reversed by 90 min of ad libitum feeding in the re-fed females (RF). In addition, food-restricted (FR) females had significantly greater GnRH content in the median eminence than either the AL or RF females. After GnRH was administered, the majority of females in all food conditions ovulated, yet the FR females had significantly fewer corpora lutea than either the AL or RF animals. These data show that food restriction impairs HPG axis function in female musk shrews, and that some of these impairments can be rapidly reversed by acute re-feeding.

  4. Disturbances in the hypothalamic-pituitary-gonadal axis in male patients with acute renal failure.

    PubMed

    Levitan, D; Moser, S A; Goldstein, D A; Kletzky, O A; Lobo, R A; Massry, S G

    1984-01-01

    The function of the hypothalamic-pituitary-gonadal (HPG) axis was examined in 20 male patients with acute renal failure. During the oliguric phase of the disease, the serum concentrations of follicle stimulating hormone (FSH) and total and unbound testosterone were markedly reduced, those of prolactin were elevated while those of luteinizing hormone (LH) were normal. The serum concentrations of sex hormone binding globulin were normal. During the diuretic phase of the illness, the serum levels of FSH and testosterone remained low but those of prolactin fell towards normal. After recovery of renal function, the abnormalities in the serum concentrations of these hormones were reversed. The responses of LH and FSH to gonadotropin releasing hormone and of prolactin to thyrotropin releasing hormone were abnormal and became normal after recovery of renal function. The results demonstrate that: (1) abnormalities in HPG axis occur early in the course of acute renal failure; (2) many features of these derangements are similar to those seen in chronic renal failure, and (3) the alterations in the function of the HPG axis are reversible when renal function is restored. The data suggest that loss of renal function, uremia per se and/or a metabolic consequence of uremia such as secondary hyperparathyroidism are responsible for these derangements.

  5. The hypothalamic-pituitary-adrenal and the hypothalamic- pituitary-gonadal axes interplay.

    PubMed

    Mastorakos, George; Pavlatou, Maria G; Mizamtsidi, Maria

    2006-01-01

    Vertebrates respond to stress with activation of the hypothalamic-pituitary-adrenal (HPA) axis, the adrenergic and the autonomic nervous systems. The principal central nervous system regulators of the HPA axis are corticotropin releasing hormone (CRH) and antidiuretic hormone (AVP). Apart from in the central nervous system, CRH has been found in the adrenal medulla, ovaries, myometrium, endometrium, placenta, testis and elsewhere. The activation of the HPA axis during stress affects all body systems. The reproductive axis is inhibited by the HPA axis for the sake of saving energy. The changes to the hypothalamic-pituitary-gonadal (HPG) axis during stress are species-specific, and depend on the type and duration of the stimulus. Several conditions may be associated with altered regulation of the HPA axis. Polycystic ovary syndrome, anorexia nervosa and pregnancy in the third trimester are all characterized by HPA axis activation. In contrast, during the postpartum period, HPA axis suppression is implicated in the "postpartum blues". The actions of CRH are also essential in fetal development and neonatal survival.

  6. The hypothalamic-pituitary-adrenocortical and gonadal axis function in rheumatoid arthritis.

    PubMed

    Cutolo, M; Giusti, M; Foppiani, L; Seriolo, B; Briata, M; Bisso, A; Faelli, F; Felli, L; Prete, C; Pizzorni, C; Sulli, A

    2000-01-01

    The altered cortisol and adrenal androgen (i.e., dehydroepiandrosterone sulfate = DHEAS) secretion, observed during testing in rheumatoid arthritis (RA) patients not treated with corticosteroids, should be clearly regarded as a "relative adrenal insufficiency" in the setting of a sustained inflammatory process, as shown by high serum IL-6 levels. Androgens seem implicated in the pathophysiology of autoimmune disorders, including RA, as natural immunosuppressors. Low plasma and synovial fluid testosterone concentrations are observed in male RA patients; low plasma DHEAS levels are mainly observed in female RA patients. The menopausal peak of RA suggests that estrogens and/or progesterone deficiency also play a role in the disease, and many data indicate that estrogens suppress cellular immunity, but stimulate humoral immunity (i.e., deficiency promotes cellular Th1-type immunity). Gene polymorphisms for enzymes involved in the steroidogenesis seem to further complicate the role of sex hormones in the susceptibility to autoimmunity. Acquired changes of sex steroid metabolism seem to also play a role in the peripheral sex hormone levels. In conclusion, a complex interaction between the hypothalamus-pituitary-adrenocortical and gonadal axis functions is evident in RA.

  7. Maturation of the pituitary-gonadal system in the male rat.

    PubMed

    Piacsek, B E; Goodspeed, M P

    1978-01-01

    Serum FSH and testosterone concentrations reached maximum levels between 35 and 45 days of age, which coincided with the appearance of mature spermatozoa in the majority of seminiferous tubules. Spermatozoa were not observed in sections of the urethra until the age of 46 days. Serum LH concentrations were low (5-6 ng/ml) before Day 25, became highly variable (12-57 ng/ml) between Days 25 and 53 and remained consistently above 35 ng/ml thereafter. Serum prolactin levels rose significantly between 30 and 43 days of age. Maximum prolactin levels coincided with the start of accelerated growth in the prostate and seminal vesicle glands. Testicular weights relative to body weight reached a plateau by 35 days of age, while relative pituitary and adrenal weights decreased throughout the study period. It is suggested that spermatogenesis is not complete until FSH and testosterone reach maximum levels, while prolactin may be involved in the stimulation of accessory sex organ growth. The pronounced variation in serum LH concentrations during the maturation period may reflect a progressive change in the sensitivity of the hypothalamic-pituitary axis to the negative feedback of gonadal steroids.

  8. Effects of alcohol on the hypothalamic-pituitary-gonadal axis in the developing male rat.

    PubMed

    Little, P J; Adams, M L; Cicero, T J

    1992-12-01

    The ontogeny of the effects of alcohol on serum testosterone levels was examined in male rats throughout sexual maturation (25-70 days). Alcohol decreased serum testosterone levels in rats 45 days or older as expected. In contrast to these results, we found precisely the opposite effects in prepubescent male rats (25-30 days old): namely, a marked stimulation of serum testosterone. Alcohol produced dose-dependent increases in serum testosterone levels in the prepubescent animal with increases of over 300% observed. In contrast to the biphasic effects of alcohol on serum testosterone levels in the developing animal, we found either no changes or modest decreases in serum luteinizing hormone levels at all ages tested. These data indicate that the increase in testosterone occurred independently of changes in luteinizing hormone in the prepubescent animal. Thus, it appears that the primary site of action of alcohol on the hypothalamic-pituitary-gonadal axis in prepubescent male rats is the testes and that alcohol acts to directly stimulate testosterone's biosynthesis. In contrast, alcohol appears to act at both central and testicular sites in rats 45 days or older to depress the synthesis and release of testosterone. The mechanisms underlying these age-dependent, biphasic effects of alcohol on serum testosterone levels are unknown at the present time, but it seems unlikely that differences in the biodisposition of alcohol were involved.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Central and peripheral administration of kisspeptin-10 stimulates the hypothalamic-pituitary-gonadal axis.

    PubMed

    Thompson, E L; Patterson, M; Murphy, K G; Smith, K L; Dhillo, W S; Todd, J F; Ghatei, M A; Bloom, S R

    2004-10-01

    Kisspeptin is the peptide product of the KiSS-1 gene and the endogenous agonist for the GPR54 receptor. Recent evidence suggests the kisspeptin/GPR54 system is a key regulator of the reproductive system. We examined the effect of intracerebroventricular (i.c.v.) and peripheral administration of the active kisspeptin fragment, kisspeptin-10, on circulating gonadotrophins and total testosterone levels in adult male rats. The effect of kisspeptin-10 in vitro on the release of hypothalamic peptides from hypothalamic explants and gonadotrophins from anterior pituitary fragments was also determined. The i.c.v. administration of kisspeptin-10 dose-dependently increased plasma luteinizing hormone (LH) and increased plasma follicle stimulating hormone (FSH) and total testosterone at 60 min postinjection. In a separate study investigating the time course of this response, i.c.v. administered kisspeptin-10 (3 nmol) significantly increased plasma LH at 10, 20 and 60 min, FSH at 60 min and total testosterone at 20 and 60 min postinjection. Kisspeptin-10 stimulated the release of luteinizing hormone-releasing hormone (LHRH) from in vitro hypothalamic explants. Peripheral administration of kisspeptin-10 increased plasma LH, FSH and total testosterone. However, doses of 100-1000 nM kisspeptin-10 did not influence LH or FSH release from pituitary fragments in vitro. Kisspeptin therefore potently stimulates the hypothalamic-pituitary-gonadal axis. These effects are likely to be mediated via the hypothalamic LHRH system.

  10. Neuroendocrine-gonadal axis in men: frequent sampling of LH, FSH, and testosterone.

    PubMed

    Spratt, D I; O'Dea, L S; Schoenfeld, D; Butler, J; Rao, P N; Crowley, W F

    1988-05-01

    Previous studies of episodic hormone secretion of the hypothalamic-pituitary-gonadal axis in normal men have produced conflicting results due to examinations of small cohorts of subjects or to limited sampling techniques. We evaluated gonadotropin and testosterone (T) secretory patterns in 20 normal men by sampling blood at 10-min intervals for luteinizing hormone (LH) and follicle-stimulating hormone (FSH). T concentrations were also analyzed at 20-min intervals in 10 subjects. A previously unappreciated spectrum of gonadotropin and T secretory patterns was observed in normal men. Both mean LH concentrations and mean LH pulse amplitudes varied fourfold between individuals. LH interpulse intervals varied from 30 to 480 min (mean 119 +/- 32). Results also suggested a relative refractory period at the level of the hypothalamus or pituitary. In three subjects, a striking nighttime accentuation of LH pulsations was noted. Through use of Fourier analysis, a diurnal variation in LH was observed in the population (P less than 0.02). Mean FSH levels showed marked variation between individual subjects, with discrete pulses rarely observed. No diurnal variation in FSH secretion was noted. Serum T concentrations determined at 6-h intervals ranged from 105 to 1,316 ng/dl between subjects. When T was measured at 20-min intervals, marked intermittent declines in the T concentrations to levels well below the normal range were observed in 3 of 10 subjects. T secretion was found to lag behind LH secretion by approximately 40 min (P less than 0.02).

  11. The pituitary-gonadal axis in experimental nephrotic syndrome in male rats.

    PubMed

    Elias, A N; Carreon, G; Vaziri, N D; Pandian, M R; Oveisi, F

    1992-12-01

    Basal and luteinizing releasing hormone-stimulated gonadotropin secretion were studied in male rats made nephrotic with puromycin, and in pair-fed and normal control animals. In addition, plasma concentrations of testosterone, androstenedione, estradiol, and estrone were measured in the three groups of animals. Urinary testosterone concentrations were also measured in the three experimental groups. The data showed that basal luteinizing hormone concentration was significantly elevated in the nephrotic group compared with the pair-fed and normal control groups. Gonadotropin response to luteinizing releasing hormone stimulation was not significantly different in the three groups, suggesting an intact hypothalamic-pituitary axis in nephrotic syndrome. Urinary testosterone concentration in the nephrotic animals was significantly higher than in the pair-fed and normal control groups. Plasma testosterone, androstenedione, estradiol, and estrone concentrations were significantly lower in the nephrotic and pair-fed animals than in the normal control animals, indicating possibly impaired gonadal steroidogenesis in these two groups that may be related to the catabolic state of the animals. It thus appears that urinary loss of protein-bound (sex hormone binding globulin-bound) testosterone in the nephrotic syndrome leads to increased basal secretion of luteinizing hormone, presumably as a result of increased luteinizing releasing hormone secretion. This occurs to compensate for the abnormal urinary testosterone loss and is an attempt to restore plasma testosterone concentrations to normal. The higher basal plasma luteinizing hormone concentration in the nephrotic group supports this conclusion.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Effects and therapeutic potentials of kisspeptin analogs: regulation of the hypothalamic-pituitary-gonadal axis.

    PubMed

    Matsui, Hisanori; Asami, Taiji

    2014-01-01

    The hypothalamic peptide kisspeptin (metastin), the endogenous ligand of the G protein-coupled receptor KISS1R, plays a critical role in controlling GnRH release from hypothalamic GnRH neurons and thereby regulates hypothalamic-pituitary-gonadal functions. Although the therapeutic potential of kisspeptin is attractive, its susceptibility to proteolytic degradation limits its utility. To overcome this, KISS1R agonists or antagonists as peptide analogs or small molecules have been investigated. Kisspeptin analogs have been most extensively studied by reducing the length of the peptide from the original 54 amino acids to 10 amino acids or less and by substituting key amino acid residues. Also, 2 investigational kisspeptin agonist analogs have been evaluated in clinical studies in men; in agreement with animal studies, abrupt elevations in gonadotropin and testosterone levels were observed as an acute effect, followed by rapid reductions in these hormones as a chronic effect. Some studies of small-molecule KISS1R antagonists have also been published. In this review, we present a brief overview on kisspeptin/KISS1R physiology in reproductive functions and summarize the available knowledge of both agonists and antagonists. We also focus on the kisspeptin agonist analogs by summarizing key pharmacological findings from both clinical and preclinical studies, and discuss their potential therapeutic utility.

  13. Impaired hypothalamic-pituitary-gonadal axis function in men with diabetes mellitus.

    PubMed

    Maneesh, M; Jayalakshmi, H; Singh, T A; Chakrabarti, Amit

    2006-03-01

    In view of association of diabetes mellitus and male infertility, present study was designed to investigate the functional status of hypothalamic pituitary gonadal (HPG) axis in diabetic men. Thirty-five diabetic men (BMI 22.24±0.21) in the age group 20-40 (30.6±4.7) years were selected. Twenty-five healthy men (BMI 23.85±0.25), in the same age group (29.5±4.8) served as control. Blood samples were collected for hormonal and biochemical estimations. Diabetic men had significantly low serum testosterone with low LH and FSH, hypercholesterolemia, hypertriglyceridemia, hypoalbuminemia and increased oxidative stress. Low serum testosterone in diabetic men was accompanied by low LH and FSH; the inability of the pituitary gland to respond appropriately to a decline in testosterone implying central effect of high serum glucose on the interaction between the nervous and endocrine system. Nutritional deficiency, increased oxidative stress and increased aromatase activity due to excessive body fat might have also contributed to low serum testosterone.

  14. The response of the hypothalamic-pituitary-gonadal axis to fasting is modulated by leptin.

    PubMed

    Steiner, J; LaPaglia, N; Kirsteins, L; Emanuele, M; Emanuele, N

    2003-05-01

    Reproductive function is intimately related to caloric consumption. During fasting states, the hormones regulating reproduction, those of the hypothalamic-pituitary-gonadal axis, in particular, are severely altered. With the exciting observations that the obese (ob) gene product leptin, may also modulate neuroendocrine functions, we examined leptin's ability to prevent the consequences of fasting on reproductive hormones. Two groups of male rats, aged 65 days old, were either fasted and saline-injected or fasted and leptin-treated for approximately three days. Another group was given free access to rat chow. Leptin was able to prevent the fasting-induced fall of serum testosterone. Similar to testosterones dependence on leptin, leptin concentrations were somewhat dependent on testosterone. Castration accelerated the normal, age-related increase in serum leptin. Leptin also prevented the fasting-induced fall in luteinizing hormone (LH). The increase of beta-LH mRNA seen in the fasting state was prevented by leptin. There were no differences noted in luteinizing hormone releasing hormone (LHRH) mRNA among any of the groups. While neither fasting nor fasting plus leptin caused changes in serum prolactin, the increase in prolactin mRNA seen in fasted animals was prevented by leptin treatment. These data support the hypothesis that leptin plays a specific role in mediating the response of reproductive hormones to the nutritional status of the organism.

  15. Ethanol: its adverse effects upon the hypothalamic-pituitary-gonadal axis.

    PubMed

    Van Thiel, D H

    1983-01-01

    Considerable evidence has accrued over the last decade to establish that ethanol is a gonadal toxin. Such toxicity is both direct, being expressed at the level of the testes, and indirect, being expressed at the level of the hypothalamus and/or pituitary. As a result of studies performed both in man and in animals, it has been shown that ethanol abuse per se, and not the associated disease that occurs with alcohol abuse, is responsible for the impotence, loss of libido, and testicular atrophy which are seen commonly in chronic alcoholic men. With prolonged alcohol abstinence, recent studies have suggested that spontaneous recovery of normal sexual function is possible in some chronic alcoholics if testicular atrophy has not yet occurred and if their responses to clomiphene and/or luteinizing hormone--releasing factor stimulation are normal. In contrast, abstinent alcoholic men with either overt testicular atrophy or inadequate responses to such pharmacologic challenges fail to recover spontaneously despite continued alcohol abstinence and will require either a penile prosthesis or long-term oral androgen therapy to achieve "acceptable" sexual functioning.

  16. Acute iron overload leads to hypothalamic-pituitary-gonadal axis abnormalities in female rats.

    PubMed

    Rossi, Emilly M; Marques, Vinicius B; Nunes, Dieli de O; Carneiro, Maria T W D; Podratz, Priscila L; Merlo, Eduardo; dos Santos, Leonardo; Graceli, Jones B

    2016-01-01

    Iron plays a critical role in a mammal's physiological processes. However, iron tissue deposits have been shown to act as endocrine disrupters. Studies that evaluate the effect of acute iron overload on hypothalamic-pituitary-gonadal (HPG) axis health are particularly sparse. This study demonstrates that acute iron overload leads to HPG axis abnormalities, including iron accumulation and impairment in reproductive tract morphology. Female rats were treated with iron-dextran (Fe rats) to assess their HPG morphophysiology. The increasing serum iron levels due to iron-dextran treatment were positively correlated with higher iron accumulation in the HPG axis and uterus of Fe rats than in control rats. An increase in the production of superoxide anions was observed in the pituitary, uterus and ovary of Fe rats. Morphophysiological reproductive tract abnormalities, such as abnormal ovarian follicular development and the reduction of serum estrogen levels, were observed in Fe rats. In addition, a significant negative correlation was obtained between ovary superoxide anion and serum estrogen levels. Together, these data provide in vivo evidence that acute iron overload is toxic for the HPG axis, a finding that may be associated with the subsequent development of the risk of reproductive dysfunction.

  17. Neuroactive gonadal drugs for neuroprotection in male and female models of Parkinson's disease.

    PubMed

    Litim, Nadhir; Morissette, Marc; Di Paolo, Thérèse

    2016-08-01

    The existence of sex differences in Parkinson's disease (PD) incidence is well documented with greater prevalence and earlier age at onset in men than in women. These reported sex differences could be related to estrogen exposure. In PD animal models, estrogen is well documented to be neuroprotective against dopaminergic neuron loss induced by neurotoxins. Using the 1-methyl 4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) mouse model, we showed that several compounds are neuroprotective on dopaminergic neurons including estrogen, the selective estrogen receptor modulator raloxifene, progesterone, dehydroepiandrosterone, the estrogen receptor alpha (ERα) agonist PPT as well as the G protein-coupled membrane estrogen receptor (GPER1) specific agonist G1. Accumulating evidence suggests that GPER1 could be implicated in the neuroprotective effects of estrogen, raloxifene and G1 in collaboration with ERα. We recently reported that the 5α-reductase inhibitor Dutasteride is also neuroprotective and could bring an alternative to estrogens for therapy in male. Additional studies are needed to optimize therapies with these gonadal drugs into safe personalized treatments according to sex for treatment of PD. PMID:26708712

  18. On gonadic maturation and reproductive strategy in deep-sea benthic octopus Graneledone macrotyla

    NASA Astrophysics Data System (ADS)

    Guerra, Ángel; Sieiro, María Pilar; Roura, Álvaro; Portela, Julio M.; del Río, José Luís

    2013-09-01

    The new information reported in this paper is based on five maturing and mature females of the large-tuberculate octopus Graneledone macrotyla. These specimens were caught in bottom trawl surveys ATLANTIS 2009 (February 24 to April 1, 2009) and ATLANTIS 2010 (March 9 to April 5, 2010) carried out off the Argentinean Economic Exclusive Zone. Capture depth ranged from 475 to 921 m and sea bottom temperature between 2.8 and 3.1 °C. Development of the complex ovary, oviducts, and oviducal glands during gonadic maturation is described. The absence of spermathecae in the oviducal glands and the presence of fertilized eggs inside the ovary suggested that fertilization took place within the ovary. Histological techniques showed the presence of four types of oocytes. Maturing oocyte size-frequency distribution was polymodal. Fluorescence reaction showed that atresia occurred in both early and later oocyte maturation stages. Atresia affected 48-55 % of the initial number of oocytes. The maximum observed potential fecundity was estimated at 250-300 eggs. G. macrotyla showed a group-synchronous ovulation pattern, regulative atresia, and a batching spawning pattern with a few egg batches spawned intermittently over an extended period of spawning.

  19. CACN-1 is required in the Caenorhabditis elegans somatic gonad for proper oocyte development.

    PubMed

    Cecchetelli, Alyssa D; Hugunin, Julie; Tannoury, Hiba; Cram, Erin J

    2016-06-01

    CACN-1/Cactin is a conserved protein identified in a genome-wide screen for genes that regulate distal tip cell migration in the nematode Caenorhabditis elegans. In addition to possessing distal tip cells that migrate past their correct stopping point, animals depleted of cacn-1 are sterile. In this study, we show that CACN-1 is needed in the soma for proper germ line development and maturation. When CACN-1 is depleted, sheath cells are absent and/or abnormal. When sheath cells are absent, hermaphrodites produce sperm, but do not switch appropriately to oocyte production. When sheath cells are abnormal, some oocytes develop but are not successfully ovulated and undergo endomitotic reduplication (Emo). Our previous proteomic studies show that CACN-1 interacts with a network of splicing factors. Here, these interactors were screened using RNAi. Depletion of many of these factors led to missing or abnormal sheath cells and germ line defects, particularly absent and/or Emo oocytes. These results suggest CACN-1 is part of a protein network that influences somatic gonad development and function through alternative splicing or post-transcriptional gene regulation. PMID:27046631

  20. Incidence patterns and trends of gonadal and extragonadal germ cell tumors in Germany, 1998–2008

    PubMed Central

    Rusner, Carsten; Trabert, Britton; Katalinic, Alexander; Kieschke, Joachim; Emrich, Katharina; Stang, Andreas

    2014-01-01

    Background Gonadal (GGCT) and extragonal germ cell tumors [GCT (EGCT)] are thought to originate from primordial germ cells. In contrast to well reported population-based data of GGCTs in males, analyses of GGCTs in females and EGCTs in both sexes remain limited. Methods In a pooling project of nine population-based cancer registries in Germany of the years 1998–2008, 16,883 GCTs and their topographical sites were identified using ICD-O morphology and topography for those aged 15 years and older. We estimated age-specific and age-standardized incidence rates. Results Among males, the incidence of testicular GCTs increased over time. In contrast, there was no increase in the incidence of EGCTs. Among females, rates of ovarian GCTs were stable, while rates of EGCTs declined over time. The most frequent extragonadal sites were mediastinum among males and placenta among females. Conclusions Our results underline different incidence trends and distinct age-specific incidence patterns of GGCTs and EGCTs, as reported recently by several population-based registries. The differences suggest that GGCTs and EGCTs may have different etiologies. PMID:23683844

  1. Gonadal development of larval male Xenopus laevis exposed to atrazine in outdoor microcosms

    USGS Publications Warehouse

    Jooste, A.M.; Du Preez, L.H.; Carr, J.A.; Giesy, J.P.; Gross, T.S.; Kendall, R.J.; Smith, E.E.; Van Der Kraak, G. L.; Solomon, K.R.

    2005-01-01

    The potential effects of atrazine on gonadal development in metamorphs and subadults of the African clawed frog (Xenopus laevis) were studied under conditions of natural photoperiod and temperatures in outdoor microcosms from August 2002 to June 2003 in South Africa. Triplicate 1100 L microcosms for each nominal concentration of 0.0, 1, 10, and 25 ??g of atrazine/L were used. Measured atrazine concentrations varied <25% throughout the study, and no atrazine was detected in the control microcosms. Tadpoles developed well at all concentrations. On the basis of histological examination of testes of recently metamorphosed stage 66 frogs, 57% of the individuals in the reference group exhibited testicular oocytes as compared with 57, 59, and 39% of the 1, 10, and 25 ??g/L atrazine groups, respectively. The average prevalence of testicular oocytes for all of the treatments including the controls was 54% in a single testis, while, in 35% of individuals, testicular oocytes were observed in both testes. The number of testicular oocytes per individual ranged from 0 to 58 with means of 9.5, 9.8, 8.5, and 11.1 for the 0.0, 1, 10, and 25 ??g of atrazine/L groups, respectively. Ten months after metamorphosis, another subset of juveniles was examined, and the maximum number of testicular oocytes observed was five in one animal. The presence of testicular oocytes was not related to exposure to atrazine and may be a natural phenomenon during ontogeny. ?? 2005 American Chemical Society.

  2. Biotinidase deficiency due to a de novo mutation or gonadal mosaicism in a first child.

    PubMed

    Tonin, Rodolfo; Caciotti, Anna; Funghini, Silvia; la Marca, Giancarlo; Pasquini, Elisabetta; Cayton, Erica; Mooney, Sean D; Guerrini, Renzo; Morrone, Amelia

    2015-05-20

    Biotinidase deficiency (BD), which is caused by BTD genetic lesions, if untreated, can result in neurological and cutaneous manifestations. Biotin supplementation can improve or prevent symptoms. We herewith present a family, which we studied at biochemical and molecular level, after identifying the proband through a newborn screening programme. BTD gene molecular analysis showed the proband to be compound heterozygous for the c.1330G>C p.(Asp444His) mild known variant, and for the c.1475 C>T p.(Thr492Ile) new variant. Bioinformatic analysis allowed us to confirm the pathogenic role of the newly identified variant. The proband's father, who exhibited low biotinidase (BTD) enzyme activity, was homozygous for the mild variant, whereas the proband's mother, who exhibited borderline BTD values, the BTD mutation carrier status could not be detected. This is the first description of a patient with BD harbouring a variant whose origin is either de novo or the consequence of gonadal mosaicism. BTD molecular analysis and bioinformatic tools for the evaluation of pathogenicity of newly identified variants are necessary for diagnostic purposes (i.e., clarifying borderline enzyme assays and the carrier status of parents), and for genetic counselling. PMID:25795614

  3. Psychopathy's influence on the coupling between hypothalamic-pituitary-adrenal and -gonadal axes among incarcerated adolescents.

    PubMed

    Johnson, Megan M; Dismukes, Andrew R; Vitacco, Michael J; Breiman, Chelsea; Fleury, Donald; Shirtcliff, Elizabeth A

    2014-04-01

    Conduct disorder (CD) is a heterogeneous diagnosis, leading researchers to initiate studies focused on neurobiological mechanisms underlying this disorder. One specifier of CD currently considered for inclusion in the DSM-V is callous-unemotional (CU) traits, a key component of psychopathy. CU traits are thought to have neuroendocrine underpinnings, yet little is known about hypothalamic-pituitary-adrenal (HPA) and -gonadal (HPG) hormones in the context of psychopathic traits. The current study sought to identify daily coupling patterns between HPA and HPG hormones in order to clarify distinct neurobiological underpinning associated with psychopathic/CU traits. Fifty incarcerated adolescent males who met criteria for CD were recruited and provided 10 saliva samples across 2 days. Participants completed the Psychopathy Checklist Youth Version (PCL:YV) and Inventory of Callous Unemotional Traits (ICU) on a third day. Diurnal cortisol, testosterone, and DHEA functioning was modeled via hierarchical linear modeling. Psychopathy subscales from the measures administered were used as predictors of daily coupling patterns between these hormones. Results indicated all three hormones were tightly coupled. Further, higher PCL-YV interpersonal scores related to greater coupling between all three hormones, whereas higher ICU callousness scores related to greater uncoupling of testosterone with cortisol and DHEA. The current study is novel in its emphasis on testing the coupling of HPA and HPG hormones among incarcerated adolescent males. Results suggest that affective and interpersonal psychopathic traits are marked by unique HPA- and HPG coupling. PMID:23852424

  4. Serum gonadotropins and gonadal steroids associated with ovulation and egg production in sea turtles.

    PubMed

    Wibbels, T; Owens, D W; Licht, P; Limpus, C; Reed, P C; Amoss, M S

    1992-07-01

    Changes in serum concentrations of gonadotropins and gonadal steroids during the periovulatory period were monitored in green, Chelonia mydas, and loggerhead, Caretta caretta, sea turtles. Turtles were from natural populations that nest on a coral island on the Great Barrier Reef. After nesting, each turtle was transferred to a holding tank and held for a maximum of 8 days. A time series of blood samples was obtained from each of five sea turtles (three C. mydas and two C. caretta) starting immediately after nesting and then at approximately 12-hr intervals until the time of release. Prior to release back into the ocean, each turtle was examined by laparoscopy to verify that ovulation had occurred. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), progesterone (PRO), and testosterone (T) in both species exhibited significant changes during this period. Surges of FSH, LH, and PRO were evident within approximately 20 to 50 hr after each turtle had nested. The significant change in FSH concentration during the periovulatory period is the first such report for a reptile. Coincident with maximal concentrations of FSH, LH, and PRO was a decline in T concentrations in both species. Estradiol-17 beta concentrations were near or below assay sensitivity in the C. mydas, whereas those in the C. caretta were detectable but exhibited no significant changes. The dynamic changes in FSH, LH, PRO, and T concentrations are consistent with the hypothesis that these hormones facilitate specific physiological events during ovulation and egg production.

  5. Pineal physiology in microgravity - Relation to rat gonadal function aboard Cosmos 1887

    NASA Technical Reports Server (NTRS)

    Holley, Daniel C.; Markley, Carol L.; Soliman, Magdi R. I.; Kaddis, Farida; Krasnov, Igor'

    1991-01-01

    Results are reported from an analysis of pineal glands obtained for five male rats flown aboard an orbiting satellite for their melatonin, serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIA), and calcium content. Plasma 5-HT and 5-HIAA were measured. These parameters were compared to indicators of gonadal function: plasma testosterone concentration and spermatogonia development. Plasma melotonin was found to be low at the time of euthanasia and was not different among the experimental groups. Pineal calcium of flight animals was not different from ground controls. Pineal 5-HT and 5-HIAA in the flight group were significantly higher than those in ground controls. These findings suggest a possible increase in pineal 5-HT turnover in flight animals which may result in increased melatonin secretion. It is argued that the alteration of pinal 5-HT turnover and its expected effects on melatonin secretion may partially explain the lower plasma testosterone levels and 4-11 percent fewer spermatogonia cells observed in flight animals.

  6. The screening of everyday life chemicals in validated assays targeting the pituitary-gonadal axis.

    PubMed

    Tinwell, H; Colombel, S; Blanck, O; Bars, R

    2013-07-01

    Ten structurally diverse chemicals (vitamins C, B9, B6, B3, sucrose, caffeine, gingerol, xanthan gum, paracetamol, ibuprofen) deemed intrinsic to modern life but not considered as endocrine active, were tested in vitro using the human estrogen receptor transcriptional activation (hERTa) and the H295R steroidogenesis assays. All were inactive in the hERTa assay but paracetamol, gingerol, caffeine and vitamin C affected steroidogenesis in vitro from 250, 25, 500 and 750 μM respectively. One molecule, caffeine, was further tested in rat pubertal assays at the tumorigenic dose-level and at dose-levels relevant for human consumption. In females pubertal parameters (vaginal opening, estrus cycle), ovarian weight and Fsh and prolactin transcript levels were affected. In males, plasma progesterone levels and prostate and seminal vesicle weights were affected. Although the current regulatory focus is synthetic chemicals that can cause adverse effects on the hypothalamus-pituitary-gonadal axis, our data infer that the range of natural chemicals with the potential to affect this axis may be extensive and is probably overlooked. Thus, to avoid regulation of an overwhelming number of chemicals, a weight of evidence approach, combining hazard identification and characterization with exposure considerations, is needed to identify those chemicals of real regulatory concern. PMID:23590819

  7. Inhibitory effects of homeodomain-interacting protein kinase 2 on the aorta-gonad-mapharsen hematopoiesis

    SciTech Connect

    Ohtsu, Naoki; Nobuhisa, Ikuo; Mochita, Miyuki; Taga, Tetsuya . E-mail: taga@kaiju.medic.kumamoto-u.ac.jp

    2007-01-01

    Definitive hematopoiesis starts in the aorta-gonad-mesonephros (AGM) region of the mouse embryo. Our previous studies revealed that STAT3, a gp130 downstream transcription factor, is required for AGM hematopoiesis and that homeodomain-interacting protein kinase 2 (HIPK2) phosphorylates serine-727 of STAT3. HIPK2 is a serine/threonine kinase known to be involved in transcriptional repression and apoptosis. In the present study, we examined the role of HIPK2 in hematopoiesis in mouse embryo. HIPK2 transcripts were found in fetal hematopoietic tissues such as the mouse AGM region and fetal liver. In cultured AGM cells, HIPK2 protein was detected in adherent cells. Functional analyses of HIPK2 were carried out by introducing wild-type and mutant HIPK2 constructs into AGM cultures. Production of CD45{sup +} hematopoietic cells was suppressed by forced expression of HIPK2 in AGM cultures. This suppression required the kinase domain and nuclear localization signals of HIPK2, but the kinase activity was dispensable. HIPK2-overexpressing AGM-derived nonadherent cells did not form cobblestone-like colonies in cultures with stromal cells. Furthermore, overexpression of HIPK2 in AGM cultures impeded the expansion of CD45{sup low}c-Kit{sup +} cells, which exhibit the immature hematopoietic progenitor phenotype. These data indicate that HIPK2 plays a negative regulatory role in AGM hematopoiesis in the mouse embryo.

  8. Immune function, sex ratios, and gonadal histopathology in double-crested cormorant chicks

    SciTech Connect

    Burull, E.J.; Goldberg, D.R.; Sileo, L.; Dale, T.; Allen, P.D.; Stromborg, K.L.; Larson, J.X.; Fry, D.M.

    1994-12-31

    There is evidence that environmental contaminants may be associated with endocrine and reproductive system abnormalities in colonial water birds. Little information is available on immune system response in chicks. Two double-crested cormorant (Phalocrocrozax auritus) colonies were monitored in 1993 for a comparative immune function study. Higher concentrations of organochlorines occurred in one colony. Parameters measured included: CBC, T and B-cell function, heterophil phagocytosis, lymphoid organ size and histopathology, and selected serum hormone analysis. Significant differences at the contaminated site included marked dysplasia and hypertrophy of thyroid gland, higher T3, lower cortisol, lower eosinophil counts, and increase phagocytosis at the contaminated site. Gonads of 101 deformed (cross-bill) chicks, siblings, and normal control chicks collected in 1992 and 1993 were examined microscopically because a sex-ration skewed towards females had been noted. Cross-billed chicks aged 12 to 15 days had disorganized or delayed follicular development which normalized by 20 days of age. Cross-billed or otherwise abnormal chicks aged 18 to 23 days had hypertrophic seminiferous tubules, a decreased interstitium, and decreased evidence of active Leydig cells.

  9. Proteomics analysis of Xenopus laevis gonad tissue following chronic exposure to atrazine.

    PubMed

    Chen, Xiuping; Wang, Jiamei; Zhu, Haojun; Ding, Jiatong; Peng, Yufa

    2015-08-01

    Atrazine is the most commonly detected pesticide contaminant in ground and surface water. Previous studies have shown that atrazine is an endocrine disruptor owing to its adverse effects on the male reproductive system in several vertebrates, but very few molecular mechanisms for these effects have been revealed. In the present study, Xenopus laevis were exposed to 100 ppb of atrazine for 120 d, and then the isobaric tags for relative and absolute quantitation (iTRAQ) technique was used to detect global changes in protein profiles of the testes and ovaries. The results showed that 100 ppb of atrazine exposure adversely affected the growth of X. laevis and did not induce hermaphroditism but delayed or prevented the development of male seminiferous tubules. Proteomic analysis showed that atrazine altered expression of 143 and 121 proteins in the testes and ovaries, respectively, and most of them are involved in cellular and metabolic processes and biological regulation based on their biological processes. In addition, apoptosis, tight junctions, and metabolic pathways were significantly altered in the atrazine-treated gonads. Based on the above results, it is postulated that the reproductive toxicity of atrazine may be the result of disruption of tight junctions and metabolic signaling pathways and/or induction of apoptosis in germ cells.

  10. Gonadal development of larval male Xenopus laevis exposed to atrazine in outdoor microcosms.

    PubMed

    Jooste, Alarik M; Du Preez, Louis H; Carr, James A; Giesy, John P; Gross, Timothy S; Kendall, Ronald J; Smith, Ernest E; Van der Kraak, Glen L; Solomon, Keith R

    2005-07-15

    The potential effects of atrazine on gonadal development in metamorphs and subadults of the African clawed frog (Xenopus laevis) were studied under conditions of natural photoperiod and temperatures in outdoor microcosms from August 2002 to June 2003 in South Africa. Triplicate 1100 L microcosms for each nominal concentration of 0.0, 1, 10, and 25 microg of atrazine/L were used. Measured atrazine concentrations varied <25% throughout the study, and no atrazine was detected in the control microcosms. Tadpoles developed well at all concentrations. On the basis of histological examination of testes of recently metamorphosed stage 66 frogs, 57% of the individuals in the reference group exhibited testicular oocytes as compared with 57, 59, and 39% of the 1, 10, and 25 microg/L atrazine groups, respectively. The average prevalence of testicular oocytes for all of the treatments including the controls was 54% in a single testis, while, in 35% of individuals, testicular oocytes were observed in both testes. The number of testicular oocytes per individual ranged from 0 to 58 with means of 9.5, 9.8, 8.5, and 11.1 forthe 0.0, 1, 10, and 25 microg of atrazine/L groups, respectively. Ten months after metamorphosis, another subset of juveniles was examined, and the maximum number of testicular oocytes observed was five in one animal. The presence of testicular oocytes was not related to exposure to atrazine and may be a natural phenomenon during ontogeny.

  11. Mutagenicity of Tris(2,3-dibromopropyl) phosphate in mammalian gonad and bone marrow tissue

    SciTech Connect

    Salamone, M.F.; Katz, M.

    1981-04-01

    The mutagenic and clastogenic (chromosome breaking) effects of the flame retardant Tris(2,3-dibromopropyl) phosphate (Tris-BP) were investigated in two mammalian in vivo assays, the bone marrow micronucleus test and the abnormal sperm head assay. Two potency of Tris-BP was determined in the Salmonella-mammalian microsome assay. Tris-BP was mutagenic in all three assays, in both mammalian tests, nearly toxic doses were required in B6C3F mice for positive mutagenic and clastogenic results. In the micronucleus test, Tris-BP was a weak clastogen, whereas in the abnormal sperm head assay, Tris-BP was observed to be strongly mutagenic. The abnormal sperm head data might imply genetic damage to germ tissue. The data suggested a means for possibly monitoring Tris-BP exposure. Thus besides being a strong mutagen on bacterial systems, Tris-BP was also a weak clastogen as detected in bone marrow cells and was a mutagen to gonad tissue.

  12. Anticoagulant Activity and Structural Characterization of Polysaccharide from Abalone (Haliotis discus hannai Ino) Gonad.

    PubMed

    Zhao, Jun; Yang, Jingfeng; Song, Shuang; Zhou, Dayong; Qiao, Weizhou; Zhu, Ce; Liu, Shuyin; Zhu, Beiwei

    2016-01-01

    In this study, we aimed at characterizing the structure and the anticoagulant activity of a polysaccharide fraction (AGP33) isolated from the gonads of Haliotis discus hannai Ino. AGP33 was extracted by enzymatic hydrolysis and purified by ion-exchange and gel-filtration chromatography. The backbone fraction of AGP33 (BAGP33), which appeared to contain of mannose, glucose and galactose, was prepared by partial acid hydrolysis. According to methylation and nuclear magnetic resonance (NMR) spectroscopy, the backbone of AGP33 was identified as mainly consisting of 1→3-linked, 1→4-linked, and 1→6-linked monosaccharides. AGP33 is a sulfated polysaccharide with sulfates occur at 3-O- and 4-O-positions. It prolonged thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) compared to a saline control solution in a dosage-dependent manner. AGP33 exhibited an extension (p < 0.01) of APTT compared to the saline group at concentrations higher than 5 μg/mL. AGP33 exhibited higher anticoagulant activity than its desulfated product (AGP33-des) and BAGP33. The results showed that polysaccharide with higher molecular weight and sulfate content demonstrated greater anticoagulant activity. PMID:27338320

  13. Anticoagulant Activity and Structural Characterization of Polysaccharide from Abalone (Haliotis discus hannai Ino) Gonad.

    PubMed

    Zhao, Jun; Yang, Jingfeng; Song, Shuang; Zhou, Dayong; Qiao, Weizhou; Zhu, Ce; Liu, Shuyin; Zhu, Beiwei

    2016-06-08

    In this study, we aimed at characterizing the structure and the anticoagulant activity of a polysaccharide fraction (AGP33) isolated from the gonads of Haliotis discus hannai Ino. AGP33 was extracted by enzymatic hydrolysis and purified by ion-exchange and gel-filtration chromatography. The backbone fraction of AGP33 (BAGP33), which appeared to contain of mannose, glucose and galactose, was prepared by partial acid hydrolysis. According to methylation and nuclear magnetic resonance (NMR) spectroscopy, the backbone of AGP33 was identified as mainly consisting of 1→3-linked, 1→4-linked, and 1→6-linked monosaccharides. AGP33 is a sulfated polysaccharide with sulfates occur at 3-O- and 4-O-positions. It prolonged thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) compared to a saline control solution in a dosage-dependent manner. AGP33 exhibited an extension (p < 0.01) of APTT compared to the saline group at concentrations higher than 5 μg/mL. AGP33 exhibited higher anticoagulant activity than its desulfated product (AGP33-des) and BAGP33. The results showed that polysaccharide with higher molecular weight and sulfate content demonstrated greater anticoagulant activity.

  14. Gonad morphogenesis defects drive hybrid male sterility in asymmetric hybrid breakdown of Caenorhabditis nematodes

    PubMed Central

    Dey, Alivia; Jin, Qi; Chen, Yen-Chu; Cutter, Asher D.

    2014-01-01

    Determining the causes and evolution of reproductive barriers to gene flow between populations, speciation, is the key to understanding the origin of diversity in nature. Many species manifest hybrid breakdown when they intercross, characterized by increasingly exacerbated problems in later generations of hybrids. Recently, Caenorhabditis nematodes have emerged as a genetic model for studying speciation, and here we investigate the nature and causes of hybrid breakdown between C. remanei and C. latens. We quantify partial F1 hybrid inviability and extensive F2 hybrid inviability; the ~75% F2 embryonic arrest occurs primarily during gastrulation or embryonic elongation. Moreover, F1 hybrid males exhibit Haldane’s rule asymmetrically for both sterility and inviability, being strongest when C. remanei serves as maternal parent. We show that the mechanism by which sterile hybrid males are incapable of transferring sperm or a copulatory plug involves defective gonad morphogenesis, which we hypothesize results from linker cell defects in migration and/or cell death during development. This first documented case of partial hybrid male sterility in Caenorhabditis follows expectations of Darwin’s corollary to Haldane’s rule for asymmetric male fitness, providing a powerful foundation for molecular dissection of intrinsic reproductive barriers and divergence of genetic pathways controlling organ morphogenesis. PMID:25196892

  15. Effects of environmentally relevant concentrations of atrazine on gonadal development of snapping turtles (Chelydra serpentina).

    PubMed

    de Solla, Shane R; Martin, Pamela A; Fernie, Kimberly J; Park, Brad J; Mayne, Gregory

    2006-02-01

    The herbicide atrazine has been suspected of affecting sexual development by inducing aromatase, resulting in the increased conversion of androgens to estrogens. We used snapping turtles (Chelydra serpentina), a species in which sex is dependent on the production of estrogen through aromatase activity in a temperature-dependent manner, to investigate if environmentally relevant exposures to atrazine affected gonadal development. Eggs were incubated in soil to which atrazine was applied at a typical field application rate (3.1 L/ha), 10-fold this rate (31 L/ha), and a control rate (no atrazine) for the duration of embryonic development. The incubation temperature (25 degrees C) was selected to produce only males. Although some males with testicular oocytes and females were produced in the atrazine-treated groups (3.3-3.7%) but not in the control group, no statistical differences were found among treatments. Furthermore, snapping turtle eggs collected from natural nests in a corn field were incubated at the pivotal temperature (27.5 degrees C) at which both males and females normally would be produced, and some males had oocytes in the testes (15.4%). The presence of low numbers of males with oocytes may be a natural phenomenon, and we have limited evidence to suggest that the presence of normal males with oocytes may represent a feminizing effect of atrazine. Histological examination of the thyroid gland revealed no effect on thyroid morphology. PMID:16519315

  16. Fecal steroid monitoring for assessing gonadal and adrenal activity in the golden eagle and peregrine falcon.

    PubMed

    Staley, Airica M; Blanco, Juan M; Dufty, Alfred M; Wildt, David E; Monfort, Steven L

    2007-08-01

    We examined the efficacy of noninvasive monitoring of endocrine function via fecal steroid immunoassays in the golden eagle and peregrine falcon. High-pressure liquid chromatography analyses of fecal glucocorticoid metabolites (fGCM) revealed that minor percentages of immunoreactive fGCM co-eluted with [(3)H]corticosterone in both sexes of the eagle (2.5-2.7%) and falcon (7.5-11.9%). In contrast, most fecal estrogen metabolites in eagle and falcon females co-eluted with radiolabeled estradiol-17beta ([(3)H]; 57.6, 64.6%, respectively) or estrone ([(3)H]; 26.9, 4.1%, respectively). Most fecal progestin metabolite immunoreactivity in the female eagle (24.8%) and falcon (21.7%) co-eluted with progesterone ([(14)C]). Most fecal androgen metabolite immunoreactivity in eagle (55.8%) and falcon (63.7%) males co-eluted with testosterone ([(14)C]). Exogenous adrenocorticotropin hormone induced increased fGCM excretion above pre-treatment in both species, but only significantly (P < 0.05) in the eagle. Both species showed increased fGCM after saline administration, suggesting the detection of 'handling stress.' Both species exhibited enterohepatic and renal recirculation of administered steroids as demonstrated by biphasic and triphasic excretion patterns. Thus, noninvasive fecal hormone monitoring is a valid and promising tool for assessing gonadal and adrenal status in rare and threatened birds-of-prey. PMID:17464481

  17. GONAD: Genome-editing via Oviductal Nucleic Acids Delivery system: a novel microinjection independent genome engineering method in mice.

    PubMed

    Takahashi, Gou; Gurumurthy, Channabasavaiah B; Wada, Kenta; Miura, Hiromi; Sato, Masahiro; Ohtsuka, Masato

    2015-06-22

    Microinjection is considered the gold standard technique for delivery of nucleic acids (NAs; transgenes or genome editing tools such as CRISPR/Cas9 systems) into embryos, for creating genetically modified organisms. It requires sophisticated equipment as well as well-trained and highly skilled personnel to perform the micro-injection technique. Here, we describe a novel and simple microinjection-independent technique, called Genome-editing via Oviductal Nucleic Acids Delivery (GONAD). Using GONAD, we show that NAs (e.g., eGFP mRNA or Cas9 mRNA/sgRNAs) can be effectively delivered to pre-implantation embryos within the intact mouse oviduct by a simple electroporation method, and result in the desired genetic modification in the embryos. Thus GONAD can bypass many complex steps in transgenic technology such as isolation of zygotes, microinjection of NAs into them, and their subsequent transfer to pseudo-pregnant animals. Furthermore, this method can potentially be used for genome editing in species other than mice.

  18. Prenatal alcohol exposure and adolescent stress increase sensitivity to stress and gonadal hormone influences on cognition in adult female rats.

    PubMed

    Comeau, Wendy L; Lee, Kristen; Anderson, Katie; Weinberg, Joanne

    2015-09-01

    Abnormal activity of stress hormone (hypothalamic-pituitary-adrenal [HPA]), and gonadal hormone (hypothalamic-pituitary-gonadal [HPG]) systems is reported following prenatal alcohol exposure (PAE). PAE increases vulnerability of brain regions involved in regulation of these systems to stressors or challenges during sensitive periods of development, such as adolescence. In addition, HPA and HPG functions are linked to higher order functions such as executive function (EF), with dysregulation of either system adversely affecting EF processes, including attention and response inhibition, that influence cognition. However, how HPA and HPG systems interact to influence cognitive performance in individuals with an FASD is not fully understood. To investigate, we used a rat model of moderate PAE. Adolescent female PAE and control offspring were exposed to 10days of chronic mild stress (CMS) and cognitive function was assessed on the radial arm maze (RAM) in adulthood. On the final test day, animals were sacrificed, with blood collected for hormone analyses, and vaginal smears taken to assess estrus stage at the time of termination. Analyses showed that adolescent CMS significantly increased levels of CORT and RAM errors during proestrus in adult PAE but not control females. Moreover, CORT levels were correlated with estradiol levels and with RAM errors, but only in PAE females, with outcome dependent on adolescent CMS condition. These results suggest that PAE increases sensitivity to the influences of stress and gonadal hormones on cognition, and thus, in turn, that HPA and HPG dysregulation may underlie some of the deficits in executive function described previously in PAE females.

  19. Long-term caffeine-induced inhibition of EAC cell progression in relation to gonadal hormonal status.

    PubMed

    Mandal, Anup; Batabyal, Sandip K; Poddar, Mrinal K

    2007-04-01

    Inhibitory action of caffeine (a tri-methylxanthine alkaloid) on progression or pathogenesis of lung, breast and ovarian cancer including Ehrlich ascites carcinoma (EAC) cell development has been reported. This information led the authors to study the effect of long-term administration of caffeine (20 mg/kg/day; po for 22-27 consecutive days) on the development of EAC cells in relation to serum gonadal hormones (LH, FSH, 17-OH-beta-estradiol (E2) and progesterone) in adult Swiss albino female mice. Measurement of gonadal hormones in serum using RIA showed that (a) long-term caffeine treatment significantly increased LH (except for 27 consecutive days) and decreased FSH (except for 24 and 27 consecutive days) and both E2 and progesterone (except for 22 and 24 consecutive days) levels, (b) development of EAC cell for 10-15 days, significantly increased LH but decreased FSH, E2 and progesterone levels and (c) long-term caffeine consumption during the development of EAC cell (i) restored the EAC cell- or caffeine-induced induction of LH and reduction of FSH level to their normal levels and (ii) withdrew/reduced the EAC cell-induced reduction in only E2 but not progesterone level. These results therefore, suggest that prolonged caffeine exposures may inhibit the development of EAC cell through the reduction or restoration of EAC cell-induced disruption of ovarian hormonal status to their normal status via the modulation of Hypothalamic-Pituitary-Gonadal (HPG) axis.

  20. The three-way interactions between the hypothalamic-pituitary-adrenal and gonadal axes and the immune system.

    PubMed

    Torpy, D J; Chrousos, G P

    1996-05-01

    The stress system is controlled by brain nuclei at the hypothalamus and brainstem. These nuclei interact with each other and control the HPA axis and sympathetic nervous systems, respectively. Major inputs to the stress system arise from the cerebral cortex and subcortical systems, the sensory organs and nerves, and the endocrine and immune systems. The major peripheral effectors of the stress system are glucocorticoids and the catecholamines. Pathological hypoactivity of the stress system has been associated with atypical depression, the chronic fatigue/fibromyalgia syndromes and autoimmune inflammatory disease; hyperactivity with melancholic depression and anxiety disorders. The stress system responds in a quantitatively and qualitatively specific fashion to different stressors. A major role of the HPA axis is to restrain the immune system and prevent tissue damage. Reciprocal interactions between the HPA axis and immune system constitutes a new endocrine feedback loop that has given rise to the field of neuroendocrine immunology. Gonadal axis hormones directly, and indirectly via the HPA axis, alter the tone of the immune system and the quality and quantity of the inflammatory responses. Effects of the HPA axis on the gonadal axis are consistent with conservation and redirection of valuable resources towards homeostasis during times of stress. These complex interactions between the HPA axis, immune and the gonadal systems may prove to be fundamental in the genesis and perpetuation of autoimmune disease.

  1. The influence of gonadal steroids and the pituitary on the levels and composition of plasma phospholipids in the rat.

    PubMed

    Edén, S; Oscarsson, J; Jansson, J O; Svanborg, A

    1987-06-01

    Gonadal steroids have been shown to influence plasma phospholipids. In the present study, the possible interaction between gonadal steroids and the pituitary in the regulation of plasma phospholipids was studied in rats. The total phospholipid concentration (higher in females) and the fatty acid composition of plasma lecithin was different in male compared to female rats. Gonadectomy resulted in a "feminization" of plasma phospholipids (total concentration and fatty acids in lecithin) in male rats but had no effect in females. Testosterone treatment of gonadectomized males or intact females resulted in a "masculinization" of plasma phospholipids, whereas estrogen treatment of intact males resulted in a "feminization." Hypophysectomy resulted in a marked decrease in plasma phospholipid concentration and the fatty acid composition of lecithin showed a "masculine" pattern in both males and females. Neither testosterone nor estrogen treatment had any effects on plasma phospholipids in hypophysectomized male and female rats, respectively. It is concluded that gonadal steroids and the hypothalamic-pituitary axis interact in the regulation of the synthetic and perhaps also degradative pathways controlling plasma phospholipids.

  2. Acute toxic effects of 3,3'-iminodipropionitrile on hypothalamic-pituitary-gonadal axis in male rats.

    PubMed

    Takahashi, Noriyuki; Hamada, Naomi; Ishizuka, Bunpei

    2014-01-01

    Exposure to 3,3'-iminodipropionitrile (IDPN) causes persistent neurotoxicity, while its reproductive toxicity in female rats is transient, indicating that gonadotropin-releasing hormone (GnRH) neurons and gonadotrophs receive little or no damage from IDPN and that the transient gonadal toxicity may be also observed in males. To clarify these points, the acute toxic effects of IDPN on hypothalamic-pituitary-gonadal axis of male rats were examined histologically, biochemically and serologically. A single intraperitoneal injection of IDPN (1000 mg/kg body weight) induced signs of neurotoxicity within a day; nevertheless, GnRH neurons were not affected throughout the experimental period. Four days after IDPN treatment, the plasma level of testosterone but not gonadotropins decreased and active caspase 3-immunopositive spermatids increased; both parameters returned to normal levels afterwards. Data from our studies revealed that while IDPN had little or no toxic effect on GnRH neurons or gonadotrophs it was transiently toxic to gonads in both sexes.

  3. Ovarian structure protein 1: A sensitive molecular biomarker of gonadal intersex in female Japanese medaka after androgen exposure.

    PubMed

    Abdel-Moneim, Ahmed; Mahapatra, Cecon T; Hatef, Azadeh; Sepúlveda, Maria S

    2015-09-01

    Intersex in gonochoristic fish can be induced after exposure to androgens and estrogens. The main objective of the present study was to identify biomarkers that would be predictive of intersex in Japanese medaka (Oryzias latipes) after exposure to synthetic hormones. First a gene was identified, ovarian structure protein 1 (osp1), with strong female-specific expression during gonadal differentiation. The authors hypothesized that osp1 expression would decrease to male levels in females after the exposure of larvae (15-25 d postfertilization [dpf]) to 17β-trenbolone (TRB; 5 ng/L) and would increase to female levels in males exposed to 17α-ethinylestradiol (EE2; 5 ng/L) and that gonadal intersex would be induced later in life (60 dpf). Tissue distribution and cellular localization of OSP1 was investigated using Western blot and immunohistochemistry. The results indicate that this exposure regime delays testicular maturation in males and development of ovarian intersex in females. Although decreased osp1 expression in females exposed to TRB correlated to changes in ovarian phenotype, up-regulation of osp1 was not observed in males exposed to EE2. In addition, OSP1 was only observed in ovaries and localized in the cytoplasm and follicular layer of immature and mature oocytes. The authors conclude that osp1 is a promising biomarker of androgen exposure and gonadal intersex in female medaka. PMID:25914295

  4. Molecular identification and expression of the Foxl2 gene during gonadal sex differentiation in northern snakehead Channa argus.

    PubMed

    Wang, Dan-Dan; Zhang, Gui-Rong; Wei, Kai-Jian; Ji, Wei; Gardner, Jonathan P A; Yang, Rui-Bin; Chen, Kun-Ci

    2015-12-01

    Channa argus is one of the most commercially important fish species in China. Studies show that males of C. argus grow faster than females at the same age. In order to explore the sex differentiation mechanism of C. argus, we isolated the full length of the sex-related gene Foxl2 cDNA and analysed its expression patterns during gonadal sex differentiation. Alignment of known Foxl2 amino acid sequences from vertebrates confirmed the conservation of the Foxl2 open reading frame, especially the forkhead domain and C-terminal region. Quantitative RT-PCR revealed that Foxl2 is predominantly expressed in brain, pituitary, gill and ovary, with its highest level in ovary but low levels in testis and other tissues, reflecting a potential role for Foxl2 in the brain-pituitary-gonad axis in C. argus. Our ontogenetic stage data showed that C. argus Foxl2 expression was significantly upregulated from 1 to 11 days posthatching (dph) and that the initiation of expression preceded the first anatomical ovarian differentiation (27 dph), suggesting that Foxl2 might play a potential role in early gonadal sex differentiation in C. argus. In addition, the Foxl2 protein was primarily located in granulosa cells surrounding the oocytes of mature C. argus, implying that Foxl2 may have a basic function in granulosa cell differentiation and the maintenance of oocytes. PMID:26159319

  5. Levels of progesterone, testosterone, and estradiol, and androstenedione metabolism in the gonads of Lytechinus variegatus (Echinodermata:echinoidea).

    PubMed

    Wasson, K M; Gower, B A; Hines, G A; Watts, S A

    2000-06-01

    Levels of progesterone (P4), testosterone (T) and estradiol (E2) indicated significant variation among individual echinoids during the annual cycle, reflecting generally the variation in gamete development that can be observed among individuals. Testosterone and E2 levels in both the ovaries and testes were higher during the period of gonadal growth. Levels of all steroids were greatly reduced compared to those levels reported for asteroids. Differences in the levels of P4, T, and estrogens between asteroids and Lytechinus variegatus may be related to differences in gonad morphology and nutrient storage capacity between asteroids and echinoids. It was hypothesized that the low levels of steroids detected in L. variegatus reflect paracrine-like mechanisms in cell signaling as compared to endocrine-like mechanisms proposed to be involved in regulating gonad function in asteroids. Both the ovaries and testes of L. variegatus had the capacity to synthesize T and a variety of 5alpha-reduced androgens including 5alpha-androstane-3beta,17beta-diol and 5alpha-androstane-3alpha,17beta-diol (5alpha-adiols) from androstenedione (AD) in 8 h. Estrogen synthesis was not detected. The sex-specific pattern of accumulation of 5alpha-adiols in the ovaries and testes suggests that the 5alpha-adiols may affect processes related to reproduction in L. variegatus. PMID:11050687

  6. Gonadal function, fertility, and reproductive medicine in childhood and adolescent cancer patients: a national survey of Japanese pediatric endocrinologists.

    PubMed

    Miyoshi, Yoko; Yorifuji, Tohru; Horikawa, Reiko; Takahashi, Ikuko; Nagasaki, Keisuke; Ishiguro, Hiroyuki; Fujiwara, Ikuma; Ito, Junko; Oba, Mari; Kawamoto, Hiroshi; Fujisaki, Hiroyuki; Kato, Masashi; Shimizu, Chikako; Kato, Tomoyasu; Matsumoto, Kimikazu; Sago, Haruhiko; Takimoto, Tetsuya; Okada, Hiroshi; Suzuki, Nao; Yokoya, Susumu; Ogata, Tsutomu; Ozono, Keiichi

    2016-04-01

    An increasing number of pediatric cancer patients survive, and treatment-related infertility represents one of the most important issues for these patients. While official guidelines in Japan recommend long-term follow-up of childhood cancer survivors (CCSs), their gonadal function and fertility have not been clarified. To address this issue, we organized a working panel to compile evidence from long-term survivors who received treatments for cancer during childhood or adolescence. In collaboration with members of the CCS Committee of the Japanese Society for Pediatric Endocrinology (JSPE), we conducted a questionnaire survey regarding reproductive function in pediatric cancer patients. A cross-sectional survey was sent to 178 JSPE-certified councilors who were asked to self-evaluate the medical examinations they had performed. A total of 151 responses were obtained, revealing that 143 endocrinologists were involved in the care of CCSs. A quarter of the respondents reported having experienced issues during gonadal or reproductive examinations. Several survivors did not remember or fully understand the explanation regarding gonadal damage, and faced physical and psychological distress when discussing the risk of becoming infertile. Pediatric endocrinologists had anxieties regarding their patients' infertility and the risk of miscarriage, premature birth, and delivery problems. Only a limited number of endocrinologists had experience with managing childbirth and fertility preservation. Many councilors mentioned the necessity for inter-disciplinary communication among healthcare providers. Both endocrinologists and oncologists should set and follow a uniform clinical guideline that includes management of fertility of CCSs.

  7. Conservation and expression of PIWI-interacting RNA pathway genes in male and female adult gonad of amniotes.

    PubMed

    Lim, Shu Ly; Tsend-Ayush, Enkhjargal; Kortschak, R Daniel; Jacob, Reuben; Ricciardelli, Carmela; Oehler, Martin K; Grützner, Frank

    2013-12-01

    The PIWI-interacting RNA (piRNA) pathway is essential for germline development and transposable element repression. Key elements of this pathway are members of the piRNA-binding PIWI/Argonaute protein family and associated factors (e.g., VASA, MAELSTROM, and TUDOR domain proteins). PIWI-interacting RNAs have been identified in mouse testis and oocytes, but information about the expression of the different piRNA pathway genes, in particular in the mammalian ovary, remains incomplete. We investigated the evolution and expression of piRNA pathway genes in gonads of amniote species (chicken, platypus, and mouse). Database searches confirm a high level of conservation and revealed lineage-specific gain and loss of Piwi genes in vertebrates. Expression analysis in mammals shows that orthologs of Piwi-like (Piwil) genes, Mael (Maelstrom), Mvh (mouse vasa homolog), and Tdrd1 (Tudor domain-containing protein 1) are expressed in platypus adult testis. In contrast to mouse, Piwil4 is expressed in platypus and human adult testis. We found evidence for Mael and Piwil2 expression in mouse Sertoli cells. Importantly, we show mRNA expression of Piwil2, Piwil4, and Mael in oocytes and supporting cells of human, mouse, and platypus ovary. We found no Piwil1 expression in mouse and chicken ovary. The conservation of gene expression in somatic parts of the gonad and germ cells of species that diverged over 800 million yr ago indicates an important role in adult male and female gonad. PMID:24108303

  8. Effects of atrazine and chlorpyrifos on DNA methylation in the brain and gonad of the common carp.

    PubMed

    Xing, Houjuan; Wang, Chao; Wu, Hongda; Chen, Dechun; Li, Shu; Xu, Shiwen

    2015-02-01

    DNA methylation is known to play an important role in the regulation of gene expression in animal. The purpose of the present study was to examine the effect of atrazine (ATR), chlorpyrifos (CPF) and combined ATR/CPF exposure on DNA methylation in the brain and gonad of common carp (Cyprinus carpio L.). The carp were sampled after a 40-d exposure to CPF and ATR, individually or in combination, followed by a 40-d recovery to measure the levels of global DNA methylation and the expression of methylation enzymes (DNA methyltransferases (DNMTs) and methylcytosine binding domain 2 (MBD2)) in the brain and gonad tissues. The results revealed that a significant global DNA hypomethylation in the common carp exposed to ATR, CPF and their mixture was observed compared to the control fish. The MBD2 mRNA expression was up-regulated in the brain and gonad of the common carp exposed to ATR, CPF and their mixture, in contrast, the DNMTs mRNA expression was down-regulated. The information regarding the effects of ATR and CPF on DNA methylation status generated in this study is important for pesticides toxicology evaluation. However, the effect of ATR and CPF on the methylation status of specific genes, as well as its detailed mechanism requires further investigation.

  9. Molecular identification and expression of the Foxl2 gene during gonadal sex differentiation in northern snakehead Channa argus.

    PubMed

    Wang, Dan-Dan; Zhang, Gui-Rong; Wei, Kai-Jian; Ji, Wei; Gardner, Jonathan P A; Yang, Rui-Bin; Chen, Kun-Ci

    2015-12-01

    Channa argus is one of the most commercially important fish species in China. Studies show that males of C. argus grow faster than females at the same age. In order to explore the sex differentiation mechanism of C. argus, we isolated the full length of the sex-related gene Foxl2 cDNA and analysed its expression patterns during gonadal sex differentiation. Alignment of known Foxl2 amino acid sequences from vertebrates confirmed the conservation of the Foxl2 open reading frame, especially the forkhead domain and C-terminal region. Quantitative RT-PCR revealed that Foxl2 is predominantly expressed in brain, pituitary, gill and ovary, with its highest level in ovary but low levels in testis and other tissues, reflecting a potential role for Foxl2 in the brain-pituitary-gonad axis in C. argus. Our ontogenetic stage data showed that C. argus Foxl2 expression was significantly upregulated from 1 to 11 days posthatching (dph) and that the initiation of expression preceded the first anatomical ovarian differentiation (27 dph), suggesting that Foxl2 might play a potential role in early gonadal sex differentiation in C. argus. In addition, the Foxl2 protein was primarily located in granulosa cells surrounding the oocytes of mature C. argus, implying that Foxl2 may have a basic function in granulosa cell differentiation and the maintenance of oocytes.

  10. Gonadal function, fertility, and reproductive medicine in childhood and adolescent cancer patients: a national survey of Japanese pediatric endocrinologists

    PubMed Central

    Miyoshi, Yoko; Yorifuji, Tohru; Horikawa, Reiko; Takahashi, Ikuko; Nagasaki, Keisuke; Ishiguro, Hiroyuki; Fujiwara, Ikuma; Ito, Junko; Oba, Mari; Kawamoto, Hiroshi; Fujisaki, Hiroyuki; Kato, Masashi; Shimizu, Chikako; Kato, Tomoyasu; Matsumoto, Kimikazu; Sago, Haruhiko; Takimoto, Tetsuya; Okada, Hiroshi; Suzuki, Nao; Yokoya, Susumu; Ogata, Tsutomu; Ozono, Keiichi

    2016-01-01

    Abstract. An increasing number of pediatric cancer patients survive, and treatment-related infertility represents one of the most important issues for these patients. While official guidelines in Japan recommend long-term follow-up of childhood cancer survivors (CCSs), their gonadal function and fertility have not been clarified. To address this issue, we organized a working panel to compile evidence from long-term survivors who received treatments for cancer during childhood or adolescence. In collaboration with members of the CCS Committee of the Japanese Society for Pediatric Endocrinology (JSPE), we conducted a questionnaire survey regarding reproductive function in pediatric cancer patients. A cross-sectional survey was sent to 178 JSPE-certified councilors who were asked to self-evaluate the medical examinations they had performed. A total of 151 responses were obtained, revealing that 143 endocrinologists were involved in the care of CCSs. A quarter of the respondents reported having experienced issues during gonadal or reproductive examinations. Several survivors did not remember or fully understand the explanation regarding gonadal damage, and faced physical and psychological distress when discussing the risk of becoming infertile. Pediatric endocrinologists had anxieties regarding their patients’ infertility and the risk of miscarriage, premature birth, and delivery problems. Only a limited number of endocrinologists had experience with managing childbirth and fertility preservation. Many councilors mentioned the necessity for inter-disciplinary communication among healthcare providers. Both endocrinologists and oncologists should set and follow a uniform clinical guideline that includes management of fertility of CCSs. PMID:27212796

  11. Gonadal function, fertility, and reproductive medicine in childhood and adolescent cancer patients: a national survey of Japanese pediatric endocrinologists.

    PubMed

    Miyoshi, Yoko; Yorifuji, Tohru; Horikawa, Reiko; Takahashi, Ikuko; Nagasaki, Keisuke; Ishiguro, Hiroyuki; Fujiwara, Ikuma; Ito, Junko; Oba, Mari; Kawamoto, Hiroshi; Fujisaki, Hiroyuki; Kato, Masashi; Shimizu, Chikako; Kato, Tomoyasu; Matsumoto, Kimikazu; Sago, Haruhiko; Takimoto, Tetsuya; Okada, Hiroshi; Suzuki, Nao; Yokoya, Susumu; Ogata, Tsutomu; Ozono, Keiichi

    2016-04-01

    An increasing number of pediatric cancer patients survive, and treatment-related infertility represents one of the most important issues for these patients. While official guidelines in Japan recommend long-term follow-up of childhood cancer survivors (CCSs), their gonadal function and fertility have not been clarified. To address this issue, we organized a working panel to compile evidence from long-term survivors who received treatments for cancer during childhood or adolescence. In collaboration with members of the CCS Committee of the Japanese Society for Pediatric Endocrinology (JSPE), we conducted a questionnaire survey regarding reproductive function in pediatric cancer patients. A cross-sectional survey was sent to 178 JSPE-certified councilors who were asked to self-evaluate the medical examinations they had performed. A total of 151 responses were obtained, revealing that 143 endocrinologists were involved in the care of CCSs. A quarter of the respondents reported having experienced issues during gonadal or reproductive examinations. Several survivors did not remember or fully understand the explanation regarding gonadal damage, and faced physical and psychological distress when discussing the risk of becoming infertile. Pediatric endocrinologists had anxieties regarding their patients' infertility and the risk of miscarriage, premature birth, and delivery problems. Only a limited number of endocrinologists had experience with managing childbirth and fertility preservation. Many councilors mentioned the necessity for inter-disciplinary communication among healthcare providers. Both endocrinologists and oncologists should set and follow a uniform clinical guideline that includes management of fertility of CCSs. PMID:27212796

  12. 18F-fluorodeoxyglucose positron emission tomography-computed tomography finding of left gonadal vein thrombosis in a case of renal cell carcinoma.

    PubMed

    Narayan, Ravishwar; Ravishankar, Uma; Natarajan, Savita; Vohra, Sandeep

    2016-01-01

    Tumor thrombus from renal cell carcinoma is commonly reported in renal vein and inferior vena cava with a few reports of gonadal vein involvement. Here, we report a case of an elderly female who underwent fluorodeoxyglucose (FDG) positron emission tomography-computed tomography scan for initial staging of left renal cell carcinoma. Along with an FDG avid left renal mass lesion, scan also revealed FDG avid tumor thrombus in the entire length of the left gonadal vein.

  13. High-density aggregations of rodlet cells in the gonads of Greenland halibut Reinhardtius hippoglossoides, a deep-water marine flatfish.

    PubMed

    Rideout, R M; Smith, S A; Morgan, M J

    2015-05-01

    Large aggregations of rodlet cells in the gonads of male and female Greenland halibut Reinhardtius hippoglossoides are reported for the first time. These rodlet cells were not arranged epithelially but rather were found throughout the connective tissue between oocytes (females) or within lymphatic spaces between testicular lobules (males). The reason for large aggregations of rodlet cells in the gonads and not other tissues of this species is uncertain.

  14. Sexually dimorphic expression of Dmrt1 and γH2AX in germ stem cells during gonadal development in Xenopus laevis.

    PubMed

    Fujitani, Kazuko; Otomo, Asako; Wada, Mikako; Takamatsu, Nobuhiko; Ito, Michihiko

    2016-04-01

    In many animals, primordial germ cells (PGCs) migrate into developing gonads. There, they proliferate and differentiate into female and male germ stem cells (GSCs), oogonia and spermatogonia, respectively. Few studies have focused on the molecular mechanisms underlying the development of GSC sex determination. Here, we investigated the expression of the transcription factor Dmrt1 and a phosphorylated form of the histone variant H2AX (γH2AX) during gonadal development in Xenopus laevis. During early sexual differentiation, Dmrt1 was expressed in the GSCs of the ZW (female) and ZZ (male) gonads as well as somatic cells of the ZZ gonads. Notably, the PGCs and primary GSCs contained large, unstructured nuclei, whereas condensed, rounder nuclei appeared only in primary oogonia during tadpole development. After metamorphosis, Dmrt1 showed its expression in secondary spermatogonia, but not in secondary oogonia. Like Dmrt1, γH2AX was expressed in the nuclei of primary GSCs in early developing gonads. However, after metamorphosis, γH2AX expression continued in primary and secondary spermatogonia, but was barely detected in the condensed nuclei of primary oogonia. Taken together, these observations indicate that spermatogonia tend to retain PGC characteristics, compared to oogonia, which undergo substantial changes during gonadal differentiation in X. laevis. Our findings suggest that Dmrt1 and γH2AX may contribute to the maintenance of stem cell identity by controlling gene expression and epigenetic changes, respectively. PMID:27239441

  15. Development of the gonads in the triploid (ZZW and ZZZ) fowl, Gallus domesticus, and comparison with normal diploid males (ZZ) and females (ZW).

    PubMed

    Lin, M; Thorne, M H; Martin, I C; Sheldon, B L; Jones, R C

    1995-01-01

    Gonadal development in fowls aged from 1 day to more than 4.5 years was studied in 63 ZZW and 16 ZZZ triploid crossbreds and compared with normal diploid males (ZZ) and females (ZW). In the ZZW fowl, the right gonad developed into a testis (although this occurred earlier in the ZZ genotype), and a structurally-abnormal excurrent duct system containing some malformed spermatids and spermatozoa was associated with the gonad of young adults. The left gonad was an ovotestes at hatching and no excurrent ducts were associated with it. The ovarian component was much less developed than that in the ZW genotype-it started to degenerate by 1 week of age, and most of the oocytes had disappeared by about 3 weeks of age. The seminiferous tubules developed in the medullary region, but only abnormal spermatozoa were produced. Leukocytes infiltrated both gonads at about 9 months of age and the seminiferous epithelium had degenerated in most fowls over 1 year old. In ZZZ fowl, gonadal and excurrent duct development was normal, but occurred earlier than in the ZZ genotype. However, meiosis and spermiogenesis were abnormal and malformed spermatozoa were produced. The heads of spermatozoa from the ducts deferens were about 1.4-times longer in the ZZZ genotype than in the ZZ genotype, indicating that the former may be producing some diploid spermatozoa. PMID:8848586

  16. Estrogenic environmental contaminants alter the mRNA abundance profiles of genes involved in gonadal differentiation of the American bullfrog.

    PubMed

    Wolff, Stephanie E; Veldhoen, Nik; Helbing, Caren C; Ramirez, Claire A; Malpas, Janae M; Propper, Catherine R

    2015-07-15

    Wildlife and human populations are exposed to anthropogenic mixtures of chemicals in the environment that may adversely influence normal reproductive function and development. We determined the effects of exposure to estrogenic chemicals and wastewater effluent (WWE) on developing gonads of the American bullfrog, Rana (Lithobates) catesbeiana, a species whose widespread distribution make it an ideal model for environmental monitoring of endocrine effects of chemical contaminants. Premetamorphic bullfrog tadpoles were exposed to treatment vehicle, 17β-estradiol (E2; 10(-9)M) or 4-tert-octylphenol (OP; 10(-9)M, 10(-8)M, and 10(-7)M). Additionally, gonadal differentiation was evaluated in bullfrog tadpoles from a WWE-containing site versus those from a reference location receiving no WWE. In both studies, phenotypic sex, steroidogenic factor-1 (nr5a1), and aromatase (cyp19a1) mRNA levels using quantitative real-time PCR were determined. Exposure to E2 or OP did not alter sex ratios. In controls, both nr5a1 and cyp19a1 transcript levels exhibited sexual dimorphism, with males demonstrating higher levels of nr5a1 and females greater abundance of cyp19a1. However, E2 exposure increased cyp19a1 mRNA abundance in testes and decreased levels in ovaries, eliminating the sexual dimorphism observed in controls. E2-exposed males exhibited increased nr5a1 transcript levels in the testes compared to controls, while females demonstrated no E2 effect. OP treatment had no effect on female cyp19a1 mRNA abundance, but exposure to 10(-7)M OP increased testicular transcript levels. Treatment with 10(-9) and 10(-8)M OP, but not 10(-7)M, resulted in decreased abundance of nr5a1 transcript in both ovaries and testes. Animals from the field had sexually dimorphic gonadal levels of cyp19a1, but both sexes from the WWE site exhibited elevated cyp19a1 transcript abundance compared to the reference location. Individual chemical compounds and anthropogenic wastewater effluent dispersed within

  17. Estrogenic environmental contaminants alter the mRNA abundance profiles of genes involved in gonadal differentiation of the American bullfrog.

    PubMed

    Wolff, Stephanie E; Veldhoen, Nik; Helbing, Caren C; Ramirez, Claire A; Malpas, Janae M; Propper, Catherine R

    2015-07-15

    Wildlife and human populations are exposed to anthropogenic mixtures of chemicals in the environment that may adversely influence normal reproductive function and development. We determined the effects of exposure to estrogenic chemicals and wastewater effluent (WWE) on developing gonads of the American bullfrog, Rana (Lithobates) catesbeiana, a species whose widespread distribution make it an ideal model for environmental monitoring of endocrine effects of chemical contaminants. Premetamorphic bullfrog tadpoles were exposed to treatment vehicle, 17β-estradiol (E2; 10(-9)M) or 4-tert-octylphenol (OP; 10(-9)M, 10(-8)M, and 10(-7)M). Additionally, gonadal differentiation was evaluated in bullfrog tadpoles from a WWE-containing site versus those from a reference location receiving no WWE. In both studies, phenotypic sex, steroidogenic factor-1 (nr5a1), and aromatase (cyp19a1) mRNA levels using quantitative real-time PCR were determined. Exposure to E2 or OP did not alter sex ratios. In controls, both nr5a1 and cyp19a1 transcript levels exhibited sexual dimorphism, with males demonstrating higher levels of nr5a1 and females greater abundance of cyp19a1. However, E2 exposure increased cyp19a1 mRNA abundance in testes and decreased levels in ovaries, eliminating the sexual dimorphism observed in controls. E2-exposed males exhibited increased nr5a1 transcript levels in the testes compared to controls, while females demonstrated no E2 effect. OP treatment had no effect on female cyp19a1 mRNA abundance, but exposure to 10(-7)M OP increased testicular transcript levels. Treatment with 10(-9) and 10(-8)M OP, but not 10(-7)M, resulted in decreased abundance of nr5a1 transcript in both ovaries and testes. Animals from the field had sexually dimorphic gonadal levels of cyp19a1, but both sexes from the WWE site exhibited elevated cyp19a1 transcript abundance compared to the reference location. Individual chemical compounds and anthropogenic wastewater effluent dispersed within

  18. Estrogenic environmental contaminants alter the mRNA abundance profiles of genes involved in gonadal differentiation of the American bullfrog

    PubMed Central

    Wolff, Stephanie E.; Veldhoen, Nik; Helbing, Caren C.; Ramirez, Claire A.; Malpas, Janae M.; Propper, Catherine R.

    2015-01-01

    Wildlife and human populations are exposed to anthropogenic mixtures of chemicals in the environment that may adversely influence normal reproductive function and development. We determined the effects of exposure to estrogenic chemicals and wastewater effluent (WWE) on developing gonads of the American bullfrog, Rana (Lithobates) catesbeiana, a species whose widespread distribution make it an ideal model for environmental monitoring for endocrine effects of chemical contaminants. Premetamorphic bullfrog tadpoles were exposed to treatment vehicle, 17β-estradiol (E2; 10−9 M) or 4-tert-octylphenol (OP; 10−9 M, 10−8 M, and 10−7 M). Additionally, gonadal differentiation was evaluated in bullfrog tadpoles from a WWE-containing site versus those from a reference location receiving no WWE. In both studies, phenotypic sex, steroidogenic factor-1 (nr5a1), and aromatase (cyp19a1) mRNA levels using quantitative real-time PCR were determined. Exposure to E2 or OP did not alter sex ratios. In controls, both nr5a1 and cyp19a1 transcript levels exhibited sexual dimorphism, with males demonstrating higher levels of nr5a1 and females greater abundance of cyp19a1. However, E2 exposure increased cyp19a1 mRNA abundance in testes and decreased levels in ovaries, eliminating the sexual dimorphism observed in controls. E2-exposed males exhibited increased nr5a1 transcript levels in the testes compared to controls, while females demonstrated no E2 effect. OP treatment had no effect on female cyp19a1 mRNA abundance, but exposure to 10−7 M OP increased testicular transcript levels. Treatment with 10−9 and 10−8 M OP, but not 10−7 M, resulted in decreased abundance of nr5a1 transcript in both ovaries and testes. Animals from the field had sexually dimorphic gonadal levels of cyp19a1, but both sexes from the WWE site exhibited elevated cyp19a1 transcript abundance compared to the reference location. Individual chemical compounds and anthropogenic wastewater effluent dispersed

  19. Effects of high-dose simvastatin on adrenal and gonadal steroidogenesis in men with hypercholesterolemia.

    PubMed

    Dobs, A S; Schrott, H; Davidson, M H; Bays, H; Stein, E A; Kush, D; Wu, M; Mitchel, Y; Illingworth, R D

    2000-09-01

    In view of the role of both the de novo biosynthesis and receptor-mediated uptake of cholesterol for normal steroidogenesis, we evaluated whether extending the therapeutic dose of the hepatic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitor, simvastatin, to 80 mg/d would affect adrenal and gonadal steroid synthesis in men with hypercholesterolemia. To evaluate this question, we enrolled men into a multicenter randomized, placebo-controlled study lasting 12 weeks. Men with serum low-density lipoprotein cholesterol (LDL-C) more than 145 mg/dL after 6 weeks of a lipid-lowering diet were randomized to 80 mg simvastatin or placebo. Half of the subjects were asked to undergo a 6-hour infusion of corticotropin (ACTH) to evaluate cortisol synthesis, and the entire cohort received a human chorionic gonadotropin (hCG) stimulation test to assess gonadal hormone secretion using pooled serum samples taken 15 minutes apart. A total of 81 men (age, 45 +/- 11 years; 93% Caucasian) with baseline serum LDL-C of 197 mg/dL (placebo, n = 39) and 184 mg/dL (simvastatin 80 mg, n = 42) completed the study. After 12 weeks, serum LDL-C, triglycerides, and high-density lipoprotein cholesterol (HDL-C) in the simvastatin group changed by -43%, -25%, and 8%, respectively (all P < .001). The basal cortisol level and the peak serum cortisol and area under the curve response to the 6-hour ACTH infusion were comparable between the two treatment groups at baseline and after 12 weeks. The pooled total testosterone level at baseline was 541 and 513 ng/dL in the placebo and simvastatin-treated groups, respectively, which declined to 536 +/- 20.5 ng/dL (-1.5%) and 474 +/- 30.4 ng/dL (-13.6%, P = .09) after treatment (mean +/- SD). The pooled free testosterone declined by 6.3% in the simvastatin group, versus a 4.9% increase in the placebo group (P = .588), while pooled bioavailable testosterone declined 10.2% in the simvastatin group and increased 1.4% in the placebo group (P = .035

  20. Pineal and gonadal influences on ultradian locomotor rhythms of male Siberian hamsters

    PubMed Central

    Prendergast, Brian J.; Cable, Erin J.; Cisse, Yasmine M.; Stevenson, Tyler J.; Zucker, Irving

    2013-01-01

    The extent to which changes in ultradian and circadian rhythms (URs and CRs) reflect seasonal variations in pineal melatonin secretion was assessed in male Siberian hamsters transferred from long to short day lengths. The period of the locomotor activity UR increased from 2.5 h in long days to 4.5 h in short day lengths, but this and most other features of the short-day ultradian phenotype were unaffected by pinealectomy; only the short-day increase in UR amplitude was counteracted by pineal extirpation. Virtually all UR components were unaffected by gonadectomy or replacement testosterone or estradiol treatment; changes in testicular hormone secretion appear insufficient to account for seasonal fluctuation in URs. Pinealectomy did not affect activity onsets and offsets or phase angles of CR entrainment in short and long day lengths; the duration of nocturnal activity was equivalently longer in short than long days in both pinealectomized and pineal-intact hamsters. CR robustness of pinealectomized hamsters in short days was intermediate between values of long-day and short-day sham-pinealectomized males. Hourly nocturnal locomotor activity was markedly reduced in SD, and this effect was completely reversed by PINx. We conclude that seasonal transitions in UR and CR waveforms controlled by day length are mediated primarily by melatonin-independent mechanisms, with lesser contributions from melatonin-dependent processes. Most seasonal changes in ultradian and circadian rhythms in males of this species are not influenced by gonadal hormones. URs may allow animals to respond appropriately to changing environmental contingencies. In winter reduced activity combined with temporal restructuring of activity to include longer intervals of rest may be adaptive in maintaining body temperature at lower values and down-regulating energy expenditure when above ground temperatures are extremely low. PMID:23142326

  1. Maturation of the hypothalamic--pituitary--gonadal axis in the male lamb: a review.

    PubMed

    Collu, R; Savoie, S; Hamel, R; Gibb, W; Ducharme, J R

    1983-01-01

    We have studied the activity of the hypothalamic--pituitary--gonadal (HPG) axis in the male ovine fetus and newborn lamb. Circulating levels of gonadotropins, prolactin, cortisol (F), testosterone (T), dehydroepiandrosterone sulfate and delta 4androstenedione (delta 4A) were measured in fetal plasma in the third trimester of gestation and the testicular response to hCG was studied in ovine fetuses at 95 - 141 days. Ultradian variations of LH, FSH and testosterone and the testicular response to hCG also were assessed from 1 to 28 days postnatally. The data indicate that (1) fetal plasma LH, FSH, delta 4A and T levels are low from 95 days of gestation to term, while F levels increase in the last 10 days. Postnatally, F decreases rapidly. Spontaneous T peaks may occur as early as 36 hr of life. (2) Spontaneous LH and concomitant or subsequent T secretory peaks are observed by 3 days of age. (3) hCG can induce an increase in T production by interstitial cells in vitro and can increase the T testicular content and its release in the plasma from 95 days of intrauterine life. Desensitization to hCG also can be observed throughout the last trimester of gestation. We conclude that the HPG axis of the male lamb is active ty 36 - 72 hr of postnatal life and that the steroidogenic capacity of the ovine testis is developed several weeks prenatally. Consequently, the relative quiescence of the axis prenatally and in the first 24 hr of life seems to result from relatively low LH secretion and release, related to an undefined endogenous control, together with decreased Leydig cell sensitivity and relatively low enzyme activity limiting T release.

  2. Neuromedin B stimulates the hypothalamic-pituitary-gonadal axis in male rats.

    PubMed

    Boughton, C K; Patel, S A; Thompson, E L; Patterson, M; Curtis, A E; Amin, A; Chen, K; Ghatei, M A; Bloom, S R; Murphy, K G

    2013-11-10

    Neuromedin B (NMB) is a highly conserved bombesin-related peptide found in mammals. NMB mRNA is detected in the central nervous system (CNS) and is highly expressed in the rat hypothalamus, in particular the medial preoptic area and the arcuate nucleus. The mammalian bombesin family of receptors consists of three closely related G protein coupled receptors, BB1, BB2 and BB3. The BB1 receptor subtype has the highest affinity for NMB. NMB has well documented roles in the regulation of the thyroid axis and the stress axis in rats. However, there is little available data regarding the role of NMB in the regulation of the hypothalamic-pituitary-gonadal (HPG) axis. It is known that the NMB receptor is expressed in immortalised gonadotrophin releasing hormone (GnRH) releasing GT1-7 cells and murine forebrain GnRH neurons, and that anterior pituitary NMB-immunoreactivity is altered by changes in the sex steroid environment. The objective of these studies was thus to further investigate the effects of NMB on the HPG axis. Intracerebroventricular (ICV) administration of NMB (10 nmol) to adult male rats significantly increased plasma luteinising hormone (LH) levels 30 min after injection (plasma LH ng/ml; saline 0.69±0.07, 10 nmol NMB 1.33±0.17, P<0.01). In vitro, NMB stimulated GnRH release from hypothalamic explants from male rats and from hypothalamic GT1-7 cells. NMB had no significant effect on LH release from anterior pituitary explants from male rats, or from pituitary LβT2 cells in vitro. These results suggest a previously unreported role for NMB in the stimulation of the HPG axis via hypothalamic GnRH. Further work is now required to determine the receptor mediating the effects of NMB on the reproductive axis and the physiological role of NMB in reproduction.

  3. Effects of exogenous somatotropin (ST) on gonadal function in ruminants and swine.

    PubMed

    Deaver, D R; Bryan, K A

    1999-10-01

    During the past 15 years, many investigators have examined the effects of somatotropin (ST) on growth and lactation in farm animals. Throughout this period, concerns about potential effects of ST on reproduction have been expressed. The objective of the present review will be to focus on the effects of exogenous ST on the hypothalamic-pituitary-gonadal axis. Plasma progesterone is increased when recombinant bovine (rb)ST is given to cattle, early in lactation, and also to sheep. Also, the release of progesterone from cultured swine and human luteal cells is increased by ST. Treatment with rbSt increases the numbers of small follicles, but does not increase the ovulatory rate of ruminants. Doses of ST similar to those used to increase milk production do not affect the secretion of testosterone or spermatogenesis in rams or bulls. Stimulatory and inhibitory effects of exogenous ST on reproductive function of gilts have been reported. Daily injections of porcine ST (pST) delayed puberty and expression of estrus after puberty. Daily administration of pST increased the number of small follicles, but not of medium follicles, whereas administration of pST by using a sustained release implant increased the number of medium follicles. Size and weight of reproductive organs and concentration of testosterone are not affected when pST is administered for at least 42 d. However, pST enhanced testicular development and spermatogenesis when given to neonatal boars. In summary, administration of exogenous ST at doses known to alter milk production and carcass composition may have subtle positive and/or negative effects on the reproductive systems of cattle and swine; however, these effects appear to be transient.

  4. Effects of alcohol on the hypothalamic-pituitary-gonadal axis in the male rat.

    PubMed

    Cicero, T J; Badger, T M

    1977-05-01

    The effects of acute and chronic alcohol administration on serum testosterone and luteinizing hormone (LH) levels were examined in the male rat. Chronic alcohol administration resulted in depressed serum testosterone and LH levels when alcohol-fed rats were compared with rats maintained, ad libitum, on rat chow and water. However, neither testosterone nor LH levels were significantly lower in alcohol-treated rats when comparisons were made to pair-fed control animals, indicating that the nutritional deficits imposed by the chronic alcohol-feeding regimen contributed heavily to the observed reductions in the two hormones. To avoid the problems associated with a chronic drug delivery model, we injected rats with a single acute injection of alcohol. LH levels dropped significantly within 2 hours after the injection of a 2.5 g/kg dose of alcohol and remained depressed, at a level between 25 and 30% of control values, from 2 to 4 hours. By 6 hours after the injection, LH levels had returned to base-line levels. Testosterone levels were also reduced by alcohol, but this drop was not significant until at least 3 hours after the injection. Testosterone levels did not return to control levels throughout the 6-hour course of the experiment. Dose-response determinations revealed that alcohol produced a biphasic effect on serum testosterone and LH: low doses of alcohol significantly increased testosterone and LH, whereas high doses decreased the levels of both hormones. The results of these studies suggest that the ability of alcohol to depress serum testosterone levels, and thus produce symptoms of hypogonadism in the male of several species, is due to a primary effect of alcohol on the hypothalamic-pituitary aspect of the hypothalamic-pituitary-gonadal axis.

  5. Effects of maternal undernutrition on the hypothalamic-pituitary-gonadal axis function in female sheep offspring.

    PubMed

    Kotsampasi, B; Chadio, S; Papadomichelakis, G; Deligeorgis, S; Kalogiannis, D; Menegatos, I; Zervas, G

    2009-08-01

    A study was conducted to evaluate the effects of maternal undernutrition on the hypothalamic-pituitary-gonadal axis in female sheep offspring. Pregnant ewes were fed to 100% throughout pregnancy (Control) or to 50% from 0 to 30 (R1) or from 31 to 100 days of gestation (R2). Female lambs were selected and fed to appetite throughout the study. At 2, 5.5 and 10 months of age a GnRH challenge was conducted. At the age of 10 months lambs were synchronized and blood samples were collected at 3 h intervals for 72 h following sponge removal. At slaughter (10 months) ovaries were removed and examined macroscopically. Maternal undernutrition did not affect the time of the onset of puberty, defined as the first increase in plasma progesterone concentrations >or=1 ng/ml. The magnitude of the pre-ovulatory gonadotrophin surge and the time to surge were unaffected by treatment. The LH and FSH response to GnRH challenge did not differ between groups at 2 and 5.5 months but at 10 months of age a higher (p < 0.05) FSH response was found in R1 group. Although the total number of visible follicles and corpora lutea did not differ between groups, a significant higher (p < 0.05) number of small (2-3 mm diameter) follicles in R1 group and a significant lower number (p < 0.05) of corpora lutea with diameter 8-11 mm and not even one with diameter >12 mm were detected in the ovaries of R2 lambs. In conclusion, maternal undernutrition during the first month of pregnancy resulted in increased pituitary sensitivity to GnRH and increased number of small follicles in the ovary, while during mid to late gestation resulted in a reduction of large corpora lutea in female offspring.

  6. Seasonal changes in thyroid-gonadal interactions in the edible dormouse, Glis glis.

    PubMed

    Jallageas, M; Mas, N; Gautron, J P; Saboureau, M; Roussel, J P

    1992-01-01

    This study was conducted to determine changes in thyroid-gonadal interaction in the edible dormouse during the phase of the annual cycle that corresponds to the end of the breeding season (from June to September). We evaluated intra-hypothalamic luteinizing hormone-releasing hormone (LHRH) content, and plasma concentrations of luteinizing hormone (LH), testosterone, thyroid-stimulating hormone (TSH) and thyroxine (T4) in three groups of dormice: (1) controls; (2) dormice receiving sufficient T4 supplementation to maintain June levels in control animals until September, thus counteracting the seasonal reduction of T4 that normally begins in July; and (3) thyroidectomized dormice. The effect of thyroidectomy was only detectable in June, when plasma T4 concentration in the control group was maximal, and consisted of a significant decrease in plasma testosterone levels. This provides strong support for the hypothesis that thyroid function positively influences gondal function during the breeding season. The T4 supplementation resulted in a decrease in hypothalamic LHRH concentration, suggesting that an increased LHRH release led to the observed stimulated hypophyseal secretion of LH in June and September and the increased circulating testosterone levels in September. There was no detectable effect in July and August. These results show that thyroid axis activation of the hypothalamic-pituitary-gondal system is only possible during certain phases of the annual cycle, particularly evidenced here during the breeding season. They also reinforce our conclusions drawn from the thyroidectomy results. Conversely, the summer testicular regression which normally occurs after the breeding season is no longer controlled by plasma T4 levels.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. The role of kisspeptin signalling in the hypothalamic-pituitary-gonadal axis--current perspective.

    PubMed

    Javed, Zeeshan; Qamar, Unaiza; Sathyapalan, Thozhukat

    2015-01-01

    The discovery of kisspeptins in the recent past remoulded current understanding of the neuroendocrine axis relating to the regulation of human puberty and reproduction. Kisspeptins have been recognised to act upstream of GnRH and have been shown to play a vital role in the control of the hypothalamic-pituitary-gonadal axis via regulation of gonadotrophin secretion, onset of puberty, and control of fertility. KNDy (kisspeptin/neurokinin-B/dynorphin) neurons have been suggested to modulate GnRH pulsatile secretion, which is required to support reproductive function in both sexes. They have also been involved in mediating both positive and negative sex steroid feedback signals to GnRH neurons and serve as a vital connection between reproduction and metabolic status of the body. When kisspeptin is administered to healthy humans, and in patients with reproductive disorders, it strongly and directly stimulates GnRH and subsequent LH secretion and enhances LH pulse frequency. These observations suggest that kisspeptins are a potential novel therapeutic approach for treating disorders with either pathologically reduced or augmented gonadotrophins pulsatile secretion and is currently a focus of translational research. Kisspeptins have also been identified in several peripheral reproductive organs, indicating their role in modulation of ovarian function, embryo implantation, and placentation, but a great deal of work remains to be done to explore further in this regard, and the evidence is only available from studies done on animal models. In this review we will mainly focus on current available evidence related to the role of kisspeptins in controlling GnRH pulse frequency, specifically their role in puberty, fertility, and reproduction. We will also be appraising other factors that regulate the kiSS1/Kisspeptin/GPR-54 system.

  8. The effects of antipsychotic-induced hyperprolactinaemia on the hypothalamic-pituitary-gonadal axis.

    PubMed

    Smith, Shubulade; Wheeler, Michael J; Murray, Robin; O'Keane, Veronica

    2002-04-01

    Hyperprolactinaemia is commonly induced by antipsychotic medications that have dopamine-blockade as their main mechanism of action. The purpose of this study was to assess the effect of antipsychotic-induced hyperprolactinaemia on hypothalamic-pituitary-gonadal axis (HPG) function.HPG axis function was assessed in 67 consecutive outpatients who were diagnosed with schizophrenia and stabilized for a period of not less than 2 years on typical antipsychotic medication, by means of clinical history, relevant questionnaires and measurement of plasma prolactin, estradiol, progesterone, testosterone, LH, FSH, sex hormone binding globulin, and TSH levels. Normative laboratory data were used to assess whether hormone levels fell within the reference range for a normal population. There was a significant correlation between dose of medication and plasma prolactin levels for the total group (P<0.001). Prolactin levels were significantly negatively associated with sex hormone levels in females (P<0.05). Males taking antipsychotic medication had a mean prolactin level of 404.1m/IU and mean gonadotrophin and sex hormone levels that fell within normal limits. The results of this study indicate that neuroleptic-induced prolactin secretion is a dose-related side effect and, in females, the level of hyperprolactinaemia is correlated with the degree of suppression of the HPG axis. Women taking long-term prolactin-raising antipsychotic medications are likely to be hyperprolactinaemic and have an associated hypogonadal state. In males, prolactin levels remain within normal limits, but at the upper end, with no apparent disturbance of reproductive hormones.

  9. Changes in the hypothalamic-pituitary-gonadal axis in human immunodeficiency virus-infected homosexual men.

    PubMed

    Croxson, T S; Chapman, W E; Miller, L K; Levit, C D; Senie, R; Zumoff, B

    1989-02-01

    Serum total testosterone, total 17 beta-estradiol, LH, FSH, and PRL concentrations were measured by RIA in 59 homosexual men infected with the human immunodeficiency virus (32 clinically healthy antibody-positive men (HH+), 20 men with acquired immune deficiency syndrome (AIDS), and 7 men with AIDS-related complex (ARC). The results were compared with those of 26 antibody-negative homosexual men (HH-) who served as controls. The mean serum total testosterone concentration was significantly lower in the men with AIDS [414 +/- 230 (+/- SD) ng/dL (14.5 +/- 8.0)] than in the HH- men [550 +/- 172 ng/dL (19.0 +/- 6.0 nmol/L); P less than 0.05]. The mean serum LH level was significantly higher in the men with AIDS (26 +/- 14 vs. 14 +/- 4 IU/L in HH- men; P less than 0.01) and slightly but significantly higher in the men with ARC (19 +/- 8 IU/L; 0.10 greater than P greater than 0.05). Serum FSH also was significantly higher in the men with AIDS (P less than 0.05). Serum PRL was significantly higher in the men with ARC (10 +/- 2 micrograms/L; P less than 0.05) and AIDS (16 +/- 10 micrograms/L; P less than 0.001) than in the HH- men (8 +/- 3 micrograms/L). Serum sex hormone-binding globulin levels were similar in HH- men and men with AIDS as were serum T responses to hCG administration for 2 days. These results suggest that alterations of the hypothalamic-pituitary-gonadal axis indicative of primary hypogonadism accompany human immunodeficiency virus infection in homosexual men.

  10. Hypothalamic-pituitary gonadal axis and immune response imbalance during chronic filarial infections.

    PubMed

    Mavoungou, Donatien; Poaty-Mavoungou, Virginie; Ongali, Brice; Akoume, Marie Yvonne; Maka, Gontran; Mavoungou, Elie

    2005-11-01

    Bi-directional relationships operate between the hypothalamic-pituitary-gonadal axis and the immune system. Cytokines, peptide hormones and their shared receptors/ligands are used as a common biological language for communication within and between the immune and neuroendocrine systems. Such communication suggests an immunoregulatory role for the brain and a sensory function for the immune system. We used a radioimmunoassay to measure the concentrations of steroid hormones (cortisol, testosterone, estradiol and progesterone) and pituitary hormones [follicle stimulating hormone (FSH), luteinizing hormone (LH) human chorionic gonadotropin (HCG) and prolactin] in peripheral blood plasma from 78 young Gabonese women with chronic filarial infections. We used an enzyme-linked immunosorbent assay to determine the concentrations of four proinflammatory cytokines [tumor necrosis factor-alpha (TNF-alpha), gamma interferon (IFN-gamma), interleukin-1 (IL-1) and IL-6] in the same plasma samples. Progesterone was unchanged and all other steroid hormone plasma concentrations were lower in microfilaremic women than in amicrofilaremic women. The concentration of LH was higher in amicrofilaremic women, whereas the prolactin concentration was higher in microfilaremics. The plasma concentrations of TNF-alpha, IFN-gamma, IL-1 and IL-6 were higher in microfilaremic women. A strong negative correlation was found between the steroid and pituitary hormones and the pro-inflammatory cytokines. Conversely, a strong positive correlation was found between prolactin and the same cytokines. These data provide first evidence of immune system and hormonal system disturbance during chronic filarial infections and suggest that the observed imbalance should be taken into account in the diagnosis and treatment of filarial infections.

  11. Dysregulation of the hypothalamic-pituitary-gonadal axis with menopause and andropause promotes neurodegenerative senescence.

    PubMed

    Atwood, Craig S; Meethal, Sivan Vadakkadath; Liu, Tianbing; Wilson, Andrea C; Gallego, Miguel; Smith, Mark A; Bowen, Richard L

    2005-02-01

    Senescence is characterized neurologically by a decline in cognitive function, which we propose is the result of degenerative processes initiated by the dysregulation of the hypothalamic-pituitary-gonadal (HPG) axis with menopause and andropause. Compelling epidemiologic evidence to support this assertion includes the increased prevalence of Alzheimer disease (AD) in women, the correlation of serum HPG hormones with disease and the decreased incidence, and delay in the onset of AD following hormone replacement therapy. Dysregulation of the axis at this time leads to alterations in the concentrations of all serum HPG hormones (decreased neuronal sex steroid signaling, but increased neuronal gonadotropin releasing hormone, luteinizing hormone, and activin signaling). Hormones of the HPG axis, receptors for which are present in the adult brain, are important regulators of cell proliferation and differentiation during growth and development. Based on this, we propose that dysregulated HPG hormone signaling with menopause/andropause leads to the abortive reentry of differentiated neurons into the cell cycle via a process we term "dyosis." Interestingly, the major biochemical and neuropathologic changes reported for the AD brain also are intimately associated with neuron division: altered AbetaPP metabolism, Abeta deposition, tau phosphorylation, mitochondrial alterations, chromosomal replication, synapse loss, and death of differentiated neurons. Recent evidence supports the premise that AD-related biochemical changes are likely the combined result of increased mitotic signaling by gonadotropins and GnRH, decreased differentiative and neuroprotective signaling via sex steroids, and increased differentiative signaling via activins. This results in a hormonal milieu that is permissive of cell cycle reentry but does not allow completion of metaphase. Partial resetting of the axis following administration of normal endogenous sex steroids delays the onset and decreases the

  12. Exploring the gonad transcriptome of two extreme male pigs with RNA-seq

    PubMed Central

    2011-01-01

    Background Although RNA-seq greatly advances our understanding of complex transcriptome landscapes, such as those found in mammals, complete RNA-seq studies in livestock and in particular in the pig are still lacking. Here, we used high-throughput RNA sequencing to gain insight into the characterization of the poly-A RNA fraction expressed in pig male gonads. An expression analysis comparing different mapping approaches and detection of allele specific expression is also discussed in this study. Results By sequencing testicle mRNA of two phenotypically extreme pigs, one Iberian and one Large White, we identified hundreds of unannotated protein-coding genes (PcGs) in intergenic regions, some of them presenting orthology with closely related species. Interestingly, we also detected 2047 putative long non-coding RNA (lncRNA), including 469 with human homologues. Two methods, DEGseq and Cufflinks, were used for analyzing expression. DEGseq identified 15% less expressed genes than Cufflinks, because DEGseq utilizes only unambiguously mapped reads. Moreover, a large fraction of the transcriptome is made up of transposable elements (14500 elements encountered), as has been reported in previous studies. Gene expression results between microarray and RNA-seq technologies were relatively well correlated (r = 0.71 across individuals). Differentially expressed genes between Large White and Iberian showed a significant overrepresentation of gamete production and lipid metabolism gene ontology categories. Finally, allelic imbalance was detected in ~ 4% of heterozygous sites. Conclusions RNA-seq is a powerful tool to gain insight into complex transcriptomes. In addition to uncovering many unnanotated genes, our study allowed us to determine that a considerable fraction is made up of long non-coding transcripts and transposable elements. Their biological roles remain to be determined in future studies. In terms of differences in expression between Large White and Iberian pigs

  13. Meta-Analysis of Microarray Data of Rainbow Trout Fry Gonad Differentiation Modulated by Ethynylestradiol

    PubMed Central

    Depiereux, Sophie; Le Gac, Florence; De Meulder, Bertrand; Pierre, Michael; Helaers, Raphaël; Guiguen, Yann; Kestemont, Patrick; Depiereux, Eric

    2015-01-01

    Sex differentiation in fish is a highly labile process easily reversed by the use of exogenous hormonal treatment and has led to environmental concerns since low doses of estrogenic molecules can adversely impact fish reproduction. The goal of this study was to identify pathways altered by treatment with ethynylestradiol (EE2) in developing fish and to find new target genes to be tested further for their possible role in male-to-female sex transdifferentiation. To this end, we have successfully adapted a previously developed bioinformatics workflow to a meta-analysis of two datasets studying sex reversal following exposure to EE2 in juvenile rainbow trout. The meta-analysis consisted of retrieving the intersection of the top gene lists generated for both datasets, performed at different levels of stringency. The intersecting gene lists, enriched in true positive differentially expressed genes (DEGs), were subjected to over-representation