Expression profiling of c-kit and its impact after esiRNA silencing during gonadal development in catfish.

PubMed

Laldinsangi, C; Senthilkumaran, B

2018-04-03

C-kit receptor is a member of a family of growth factor receptors that have tyrosine kinase activity, and are involved in the transduction of growth regulatory signals across plasma membrane by activation of its ligand, kitl/scf. The present study analysed mRNA and protein expression profiles of c-kit in the gonads of catfish, Clarias gariepinus, using real time PCR, in situ hybridization and immunohistochemistry. Tissue distribution analysis revealed higher expression mainly in the catfish gonads. Ontogeny studies showed minimal expression during early developmental stages and highest during 50-75 days post hatch, and the dimorphic expression in gonads decreased gradually till adulthood, which might suggest an important role for this gene around later stages of sex differentiation and gonadal development. Expression of C-kit was analysed at various phases of gonadal cycle in both male and female, which showed minimal expression during the resting phase, and higher expression in male compared to females during the pre-spawning phase. In vitro and in vivo induction using human chorionic gonadotropin elevated the expression of c-kit indicating the regulatory influence of hypothalamo-hypophyseal axis. In vivo transient gene silencing using c-kit-esiRNA in adult catfish during gonadal recrudescence showed a decrease in c-kit expression, which affected the expression level of germ cell meiotic marker sycp3, as well as several factors and steroidogenic enzyme genes involved in germ cell development. Decrease in the levels of serum 11-KT and T were also observed after esiRNA silencing. The findings of this study suggest that c-kit has an important role in the process of germ cell proliferation, development and maturation during gonadal development and recrudescence in catfish. Copyright © 2018. Published by Elsevier Inc.

The timing and reproductive output of the commercial sea cucumber Holothuria scabra on the Kenyan coast

NASA Astrophysics Data System (ADS)

Muthiga, N. A.; Kawaka, J. A.; Ndirangu, S.

2009-09-01

The sea cucumber Holothuria scabra is a widely distributed and economically important species that has been harvested in Kenya for decades. No previous studies have been carried out on the reproduction of this species in Kenya. Standard gonad index methods were used to analyze reproductive patterns of individuals collected monthly in 1998-1999, 2000-2001 and 2006-2007. Morphological characteristics, gonad tubule lengths and fecundity were also measured. Mean monthly gonad indices were significantly correlated between males and females indicating synchronous gonad development between the sexes. Gonad indices showed a biannual pattern that was consistent in all three years with a minor spawning event occurring between August and September and a major spawning event between November and December. The pattern of gonad growth showed significant variability between years and between months. Temporal changes in gonad growth correlated significantly with gonad tubule length and absolute fecundity. Monthly gonad indices also correlated significantly with monthly measurements of air temperature and light suggesting a possible role for both factors in timing gametogenesis and spawning. There was a shift in sex ratio from unity in the 1998-1999 and 2000-2001 samples to significantly more males in the 2006-2007 samples, as well as a significant reduction in mean sizes (body wall weight) and reproductive output (gonad index) which suggests that the reproductive success of this species is potentially negatively affected by fishing.

[The myocardial thickness in budgerigars (Melopsittacus undulatus) and Australian king parrots (Alisterus s. scapularis)].

PubMed

Straub, Jens; Valerius, Klaus-Peter; Pees, Michael; Krautwald-Junghanns, Maria-Elisabeth

2002-01-01

Due to lack of reference values an objective assessment of myocardial dilatation and hypertrophy in cage and aviary birds so far is not possible. Therefore the thickness of the myocardium of the left and the right ventricle of the heart of 14 budgerigars (Melopsittacus undulatus) and 5 Alisterus parrots (Alisterus s. scapularis) of both sexes was examined according to a standard protocol to establish morphometric data and first reference values. In order to compare the results of birds of different sizes all data were set in relation to the size of the bird's body (length of the sternum). Results of different zones were compared by means of statistical methods within one species. Besides that a comparison between the two species was performed. Only minor significant differences could be noticed.

The organizing actions of adolescent gonadal steroid hormones on brain and behavioral development.

PubMed

Schulz, Kalynn M; Sisk, Cheryl L

2016-11-01

Adolescence is a developmental period characterized by dramatic changes in cognition, risk-taking and social behavior. Although gonadal steroid hormones are well-known mediators of these behaviors in adulthood, the role gonadal steroid hormones play in shaping the adolescent brain and behavioral development has only come to light in recent years. Here we discuss the sex-specific impact of gonadal steroid hormones on the developing adolescent brain. Indeed, the effects of gonadal steroid hormones during adolescence on brain structure and behavioral outcomes differs markedly between the sexes. Research findings suggest that adolescence, like the perinatal period, is a sensitive period for the sex-specific effects of gonadal steroid hormones on brain and behavioral development. Furthermore, evidence from studies on male sexual behavior suggests that adolescence is part of a protracted postnatal sensitive period that begins perinatally and ends following adolescence. As such, the perinatal and peripubertal periods of brain and behavioral organization likely do not represent two discrete sensitive periods, but instead are the consequence of normative developmental timing of gonadal hormone secretions in males and females. Copyright © 2016 Elsevier Ltd. All rights reserved.

The organizing actions of adolescent gonadal steroid hormones on brain and behavioral development

PubMed Central

Schulz, Kalynn M.; Sisk, Cheryl L.

2016-01-01

Adolescence is a developmental period characterized by dramatic changes in cognition, risk-taking and social behavior. Although gonadal steroid hormones are well-known mediators of these behaviors in adulthood, the role gonadal steroid hormones play in shaping the adolescent brain and behavioral development has only come to light in recent years. Here we discuss the sex-specific impact of gonadal steroid hormones on the developing adolescent brain. Indeed, the effects of gonadal steroid hormones during adolescence on brain structure and behavioral outcomes differs markedly between the sexes. Research findings suggest that adolescence, like the perinatal period, is a sensitive period for the sex-specific effects of gonadal steroid hormones on brain and behavioral development. Furthermore, evidence from studies on male sexual behavior suggests that adolescence is part of a protracted postnatal sensitive period that begins perinatally and ends following adolescence. As such, the perinatal and peripubertal periods of brain and behavioral organization likely do not represent two discrete sensitive periods, but instead are the consequence of normative developmental timing of gonadal hormone secretions in males and females. PMID:27497718

Transcriptional regulation of Drosophila gonad formation.

PubMed

Tripathy, Ratna; Kunwar, Prabhat S; Sano, Hiroko; Renault, Andrew D

2014-08-15

The formation of the Drosophila embryonic gonad, involving the fusion of clusters of somatic gonadal precursor cells (SGPs) and their ensheathment of germ cells, provides a simple and genetically tractable model for the interplay between cells during organ formation. In a screen for mutants affecting gonad formation we identified a SGP cell autonomous role for Midline (Mid) and Longitudinals lacking (Lola). These transcriptional factors are required for multiple aspects of SGP behaviour including SGP cluster fusion, germ cell ensheathment and gonad compaction. The lola locus encodes more than 25 differentially spliced isoforms and we have identified an isoform specific requirement for lola in the gonad which is distinct from that in nervous system development. Mid and Lola work in parallel in gonad formation and surprisingly Mid overexpression in a lola background leads to additional SGPs at the expense of fat body cells. Our findings support the idea that although the transcription factors required by SGPs can ostensibly be assigned to those being required for either SGP specification or behaviour, they can also interact to impinge on both processes. Copyright © 2014 Elsevier Inc. All rights reserved.

ATRX has a critical and conserved role in mammalian sexual differentiation

PubMed Central

2011-01-01

Background X-linked alpha thalassemia, mental retardation syndrome in humans is a rare recessive disorder caused by mutations in the ATRX gene. The disease is characterised by severe mental retardation, mild alpha-thalassemia, microcephaly, short stature, facial, skeletal, genital and gonadal abnormalities. Results We examined the expression of ATRX and ATRY during early development and gonadogenesis in two distantly related mammals: the tammar wallaby (a marsupial) and the mouse (a eutherian). This is the first examination of ATRX and ATRY in the developing mammalian gonad and fetus. ATRX and ATRY were strongly expressed in the developing male and female gonad respectively, of both species. In testes, ATRY expression was detected in the Sertoli cells, germ cells and some interstitial cells. In the developing ovaries, ATRX was initially restricted to the germ cells, but was present in the granulosa cells of mature ovaries from the primary follicle stage onwards and in the corpus luteum. ATRX mRNA expression was also examined outside the gonad in both mouse and tammar wallaby whole embryos. ATRX was detected in the developing limbs, craniofacial elements, neural tissues, tail and phallus. These sites correspond with developmental deficiencies displayed by ATR-X patients. Conclusions There is a complex expression pattern throughout development in both mammals, consistent with many of the observed ATR-X syndrome phenotypes in humans. The distribution of ATRX mRNA and protein in the gonads was highly conserved between the tammar and the mouse. The expression profile within the germ cells and somatic cells strikingly overlaps with that of DMRT1, suggesting a possible link between these two genes in gonadal development. Taken together, these data suggest that ATRX has a critical and conserved role in normal development of the testis and ovary in both the somatic and germ cells, and that its broad roles in early mammalian development and gonadal function have remained unchanged for over 148 million years of mammalian evolution. PMID:21672208

ATRX has a critical and conserved role in mammalian sexual differentiation.

PubMed

Huyhn, Kim; Renfree, Marilyn B; Graves, Jennifer A; Pask, Andrew J

2011-06-14

X-linked alpha thalassemia, mental retardation syndrome in humans is a rare recessive disorder caused by mutations in the ATRX gene. The disease is characterised by severe mental retardation, mild alpha-thalassemia, microcephaly, short stature, facial, skeletal, genital and gonadal abnormalities. We examined the expression of ATRX and ATRY during early development and gonadogenesis in two distantly related mammals: the tammar wallaby (a marsupial) and the mouse (a eutherian). This is the first examination of ATRX and ATRY in the developing mammalian gonad and fetus. ATRX and ATRY were strongly expressed in the developing male and female gonad respectively, of both species. In testes, ATRY expression was detected in the Sertoli cells, germ cells and some interstitial cells. In the developing ovaries, ATRX was initially restricted to the germ cells, but was present in the granulosa cells of mature ovaries from the primary follicle stage onwards and in the corpus luteum. ATRX mRNA expression was also examined outside the gonad in both mouse and tammar wallaby whole embryos. ATRX was detected in the developing limbs, craniofacial elements, neural tissues, tail and phallus. These sites correspond with developmental deficiencies displayed by ATR-X patients. There is a complex expression pattern throughout development in both mammals, consistent with many of the observed ATR-X syndrome phenotypes in humans. The distribution of ATRX mRNA and protein in the gonads was highly conserved between the tammar and the mouse. The expression profile within the germ cells and somatic cells strikingly overlaps with that of DMRT1, suggesting a possible link between these two genes in gonadal development. Taken together, these data suggest that ATRX has a critical and conserved role in normal development of the testis and ovary in both the somatic and germ cells, and that its broad roles in early mammalian development and gonadal function have remained unchanged for over 148 million years of mammalian evolution.

Characterization of Gonadal Transcriptomes from Nile Tilapia (Oreochromis niloticus) Reveals Differentially Expressed Genes

PubMed Central

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 HiseqTM 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. PMID:23658843

[The role of gonadal peptides in clinical investigation].

PubMed

Lahlou, N; Bouvattier, C; Linglart, A; Rodrigue, D; Teinturier, C

2009-01-01

Inhibins, activins, and anti-Mullerian hormone (AMH) are gonadal dimeric peptides produced in ovaries and testes by homologous cells, granulosa cells and Sertoli cells, respectively. The production of inhibins is driven by FSH, that of AMH may indirectly depends on FSH, while it is down regulated, at least in the male, by testosterone. In the past decade, measurements of serum inhibin and AMH have provided useful tools for clinical investigation in gonadal disorders: pseudohermaphroditism, androgen insensitivity, anorchidism, gonadal dysgenesis, disorders of pubertal developpement. Inhibins, activins, and AMH are also reliable markers of gonadal tumors. They are extensively used as indexes of fertility: in the male the production of inhibin B reflects the spermatogenetic activity, in women both inhibin B and AMH levels are correlated with the number of preantral and early antral follicles and reflect the ovarian reserve of follicles available for recruitment.

Histological and transcriptomic effects of 17α-methyltestosterone on zebrafish gonad development.

PubMed

Lee, Stephanie Ling Jie; Horsfield, Julia A; Black, Michael A; Rutherford, Kim; Fisher, Amanda; Gemmell, Neil J

2017-07-24

Sex hormones play important roles in teleost ovarian and testicular development. In zebrafish, ovarian differentiation appears to be dictated by an oocyte-derived signal via Cyp19a1a aromatase-mediated estrogen production. Androgens and aromatase inhibitors can induce female-to-male sex reversal, however, the mechanisms underlying gonadal masculinisation are poorly understood. We used histological analyses together with RNA sequencing to characterise zebrafish gonadal transcriptomes and investigate the effects of 17α-methyltestosterone on gonadal differentiation. At a morphological level, 17α-methyltestosterone (MT) masculinised gonads and accelerated spermatogenesis, and these changes were paralleled in masculinisation and de-feminisation of gonadal transcriptomes. MT treatment upregulated expression of genes involved in male sex determination and differentiation (amh, dmrt1, gsdf and wt1a) and those involved in 11-oxygenated androgen production (cyp11c1 and hsd11b2). It also repressed expression of ovarian development and folliculogenesis genes (bmp15, gdf9, figla, zp2.1 and zp3b). Furthermore, MT treatment altered epigenetic modification of histones in zebrafish gonads. Contrary to expectations, higher levels of cyp19a1a or foxl2 expression in control ovaries compared to MT-treated testes and control testes were not statistically significant during early gonad development (40 dpf). Our study suggests that both androgen production and aromatase inhibition are important for androgen-induced gonadal masculinisation and natural testicular differentiation in zebrafish.

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...

Transforming Growth Factor Beta (TGFβ1, TGFβ2 and TGFβ3) Null-Mutant Phenotypes in Embryonic Gonadal Development

PubMed Central

Memon, Mushtaq A.; Anway, Matthew D.; Covert, Trevor R.; Uzumcu, Mehmet; Skinner, Michael K.

2008-01-01

The role transforming growth factor beta (TGFb) isoforms TGFb1, TGFb2 and TGFb3 have in the regulation of embryonic gonadal development was investigated with the use of null-mutant (i.e. knockout) mice for each of the TGFb isoforms. Late embryonic gonadal development was investigated because homozygote TGFb null-mutant mice generally die around birth, with some embryonic loss as well. In the testis, the TGFb1 null-mutant mice had a decrease in the number of germ cells at birth, postnatal day 0 (P0). In the testis, the TGFb2 null-mutant mice had a decrease in the number of seminiferous cords at embryonic day 15 (E15). In the ovary, the TGFb2 null-mutant mice had an increase in the number of germ cells at P0. TGFb isoforms appear to have a role in gonadal development, but interactions between the isoforms is speculated to compensate in the different TGFb isoform null-mutant mice. PMID:18790002

Kisspeptin regulates the hypothalamus-pituitary-gonad axis gene expression during sexual maturation in the cinnamon clownfish, Amphiprion melanopus.

PubMed

Kim, Na Na; Shin, Hyun Suk; Choi, Young Jae; Choi, Cheol Young

2014-02-01

Kisspeptins (Kiss) have been recognized as potent regulators of reproduction in teleosts, and Kiss is suggested to be a key regulator of the hypothalamus-pituitary-gonad axis (HPG). However, its regulatory role on reproduction in fish remains unclear. Therefore, to investigate the role of Kiss on fish reproduction, this study aimed to test differences in the hormones of the HPG axis, Kiss as neuropeptides, and sex steroids on the sexual maturation of paired cinnamon clownfish, Amphiprion melanopus, following treatment with Kiss. We investigated the actions of sex maturation hormones, including HPG axis hormones and sex steroid hormones, such as gonadotropin-releasing hormones, gonadotropin hormones (GTHs), GTH receptors, estrogen receptors, and vitellogenin in the pituitary, gonads, and liver following treatment with Kiss. The expression levels of HPG axis genes increased after the Kiss injection. In addition, the levels of plasma 17α-hydroxypregnenolone, estradiol-17β, and 11-ketotestosterone increased. These results support the hypothesis that Kiss play important roles in the regulation of the HPG axis and are most likely involved in gonadal development and sexual maturation in cinnamon clownfish. Copyright © 2013 Elsevier Inc. All rights reserved.

A pioneering study on cytotoxicity in Australian parakeets (Melopsittacus undulates) exposed to tannery effluent.

PubMed

de Souza, Joyce Moreira; Montalvão, Mateus Flores; da Silva, Anderson Rodrigo; de Lima Rodrigues, Aline Sueli; Malafaia, Guilherme

2017-05-01

Waste effluent from the tannery industry is a major source of environmental pollution. Considering that the bird intake of water contaminated with tannery effluent constitutes a potential genotoxic source, especially for birds inhabiting areas closest to tanning industries, the aim of this study is to assess the possible mutagenic effects that the intake may have on Melopsittacus undulatus (Australian parakeet). In order to do so, adult male and female M. undulatus were distributed in two experimental groups: control (drinking water) and TE (5%). After 60 days of exposure, the micronucleus test, as well as tests looking for other nuclear abnormalities in the peripheral blood of the birds were performed. The male and female birds exposed to the pollutant have presented the highest total number of nuclear abnormalities, as well as increased individual abnormalities such as nuclei with symmetrical constricted bi-lobed/bi-nucleated erythrocytes, indented nuclei and micro-lobed nuclei (top)/micro-nuclei (bottom). In addition, the exposure to TE has caused a nuclear variant increase rarely reported in the literature concerning poultry erythrocyte nuclei. The birds exposed to the pollutant have presented the highest frequency of displaced nuclei forming different rotation/displacement angles within the cells. Therefore, the current study confirmed the toxicological potential of TE and was pioneer in showing that male and female M. undulatus exposed to pollutant present the highest frequency of erythrocyte nuclear abnormalities, thus corroborating the initial hypothesis herein presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transcriptome analysis identifies genes involved in sex determination and development of Xenopus laevis gonads.

PubMed

Piprek, Rafal P; Damulewicz, Milena; Kloc, Malgorzata; Kubiak, Jacek Z

Development of the gonads is a complex process, which starts with a period of undifferentiated, bipotential gonads. During this period the expression of sex-determining genes is initiated. Sex determination is a process triggering differentiation of the gonads into the testis or ovary. Sex determination period is followed by sexual differentiation, i.e. appearance of the first testis- and ovary-specific features. In Xenopus laevis W-linked DM-domain gene (DM-W) had been described as a master determinant of the gonadal female sex. However, the data on the expression and function of other genes participating in gonad development in X. laevis, and in anurans, in general, are very limited. We applied microarray technique to analyze the expression pattern of a subset of X. laevis genes previously identified to be involved in gonad development in several vertebrate species. We also analyzed the localization and the expression level of proteins encoded by these genes in developing X. laevis gonads. These analyses pointed to the set of genes differentially expressed in developing testes and ovaries. Gata4, Sox9, Dmrt1, Amh, Fgf9, Ptgds, Pdgf, Fshr, and Cyp17a1 expression was upregulated in developing testes, while DM-W, Fst, Foxl2, and Cyp19a1 were upregulated in developing ovaries. We discuss the possible roles of these genes in development of X. laevis gonads. Copyright © 2018 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

Radiological Evaluation of Ambiguous Genitalia with Various Imaging Modalities

NASA Astrophysics Data System (ADS)

Ravi, N.; Bindushree, Kadakola

2012-07-01

Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. These can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management. We describe case series on ambiguous genitalia presented to our department who were evaluated with multiple imaging modalities.

Morphometry of the heart of budgerigars (Melopsittacus undulatus), Alisterus parrots (Alisterus s scapularis) and common buzzards (Buteo buteo).

PubMed

Straub, J; Valerius, K-P; Pees, M; Krautwald-junghanns, M-E

2002-04-01

In order to establish data and reference values for the thickness of the myocardium and the length of the left and the right ventricle of the avian heart, the hearts of 14 budgerigars (Melopsittacus undulatus), five Alisterus parrots (Alisterus s scapularis) (also known as Australian king parrot) and 10 common buzzards (Buteo buteo) of both sexes were examined according to a standard protocol. In order to compare the results of birds of different sizes all data were related to the size of the bird's body (length of the sternum) and the results of the measurements of the myocardial thickness in relation to the length of the heart. Results of different zones were compared by means of statistical methods within one species. Besides that a comparison between the different species was performed. Only minor significant differences were noted. Copyright 2002 Elsevier Science Ltd. All rights reserved.

Roles of GATA6 during Gonadal Development in Japanese Flounder: Gonadogenesis, Regulation of Gender-Related Genes, Estrogen Formation and Gonadal Function Maintenance.

PubMed

Li, Zan; Liu, Xiumei; Sun, Yan; Liu, Jinxiang; Liu, Yuezhong; Wang, Mengxun; Zhang, Quanqi; Wang, Xubo

2017-01-16

GATA-binding protein 6 (GATA6), a highly-conserved transcription factor of the GATA family plays an important role in gonadal cell proliferation, differentiation and endoderm development. In this study, the full-length cDNA of GATA6 of Paralichthys olivaceus (Japanese flounder) was obtained. Phylogenetic, gene structure and synteny analyses demonstrated that GATA6 of P. olivaceus is homologous to that of teleosts and tetrapods. The P. olivaceus GATA6 transcript showed higher expression in testis than in ovary, demonstrating a sexually dimorphic gene expression. During embryonic development, the expression of P. olivaceus GATA6 increased at the blastula stage, demonstrating that GATA6 is involved in morphogenesis. Results of in situ hybridization showed that GATA6 signals were detected in Sertoli cells, oogonia and oocytes. Moreover, 17α methyl testosterone, a male hormone, could moderately upregulate P. olivaceus GATA6 and downregulate P. olivaceus aromatase CYP19A1 in testis cells. These results suggest that GATA6 may play an important role in gonadal development in P. olivaceus . This study provides valuable information on the function of P. olivaceus GATA6, laying the foundation for further development of breeding techniques in this species.

Roles of GATA6 during Gonadal Development in Japanese Flounder: Gonadogenesis, Regulation of Gender-Related Genes, Estrogen Formation and Gonadal Function Maintenance

PubMed Central

Li, Zan; Liu, Xiumei; Sun, Yan; Liu, Jinxiang; Liu, Yuezhong; Wang, Mengxun; Zhang, Quanqi; Wang, Xubo

2017-01-01

GATA-binding protein 6 (GATA6), a highly-conserved transcription factor of the GATA family plays an important role in gonadal cell proliferation, differentiation and endoderm development. In this study, the full-length cDNA of GATA6 of Paralichthys olivaceus (Japanese flounder) was obtained. Phylogenetic, gene structure and synteny analyses demonstrated that GATA6 of P. olivaceus is homologous to that of teleosts and tetrapods. The P. olivaceus GATA6 transcript showed higher expression in testis than in ovary, demonstrating a sexually dimorphic gene expression. During embryonic development, the expression of P. olivaceus GATA6 increased at the blastula stage, demonstrating that GATA6 is involved in morphogenesis. Results of in situ hybridization showed that GATA6 signals were detected in Sertoli cells, oogonia and oocytes. Moreover, 17α methyl testosterone, a male hormone, could moderately upregulate P. olivaceus GATA6 and downregulate P. olivaceus aromatase CYP19A1 in testis cells. These results suggest that GATA6 may play an important role in gonadal development in P. olivaceus. This study provides valuable information on the function of P. olivaceus GATA6, laying the foundation for further development of breeding techniques in this species. PMID:28275215

Body size and symbiotic status influence gonad development in Aiptasia pallida anemones.

PubMed

Carlisle, Judith F; Murphy, Grant K; Roark, Alison M

2017-01-01

Pale anemones ( Aiptasia pallida ) coexist with dinoflagellates (primarily Symbiodinium minutum ) in a mutualistic relationship. The purpose of this study was to investigate the role of these symbionts in gonad development of anemone hosts. Symbiotic and aposymbiotic anemones were subjected to light cycles that induced gametogenesis. These anemones were then sampled weekly for nine weeks, and gonad development was analyzed histologically. Anemone size was measured as mean body column diameter, and oocytes or sperm follicles were counted for each anemone. Generalized linear models were used to evaluate the influence of body size and symbiotic status on whether gonads were present and on the number of oocytes or sperm follicles produced. Body size predicted whether gonads were present, with larger anemones being more likely than smaller anemones to develop gonads. Both body size and symbiotic status predicted gonad size, such that larger and symbiotic anemones produced more oocytes and sperm follicles than smaller and aposymbiotic anemones. Overall, only 22 % of aposymbiotic females produced oocytes, whereas 63 % of symbiotic females produced oocytes. Similarly, 6 % of aposymbiotic males produced sperm follicles, whereas 60 % of symbiotic males produced sperm follicles. Thus, while gonads were present in 62 % of symbiotic anemones, they were present in only 11 % of aposymbiotic anemones. These results indicate that dinoflagellate symbionts influence gonad development and thus sexual maturation in both female and male Aiptasia pallida anemones. This finding substantiates and expands our current understanding of the importance of symbionts in the development and physiology of cnidarian hosts.

Nutritional modulation of IGF-1 in relation to growth and body condition in Sceloporus lizards.

PubMed

Duncan, Christine A; Jetzt, Amanda E; Cohick, Wendie S; John-Alder, Henry B

2015-05-15

Nutrition and energy balance are important regulators of growth and the growth hormone/insulin-like growth factor (GH/IGF) axis. However, our understanding of these functions does not extend uniformly to all classes of vertebrates and is mainly limited to controlled laboratory conditions. Lizards can be useful models to improve our understanding of the nutritional regulation of the GH/IGF-1 axis because many species are relatively easy to observe and manipulate both in the laboratory and in the field. In the present study, the effects of variation in food intake on growth, body condition, and hepatic IGF-1 mRNA levels were measured in (1) juveniles of Sceloporus jarrovii maintained on a full or 1/3 ration and (2) hatchlings of Sceloporus undulatus subjected to full or zero ration with or without re-feeding. These parameters plus plasma IGF-1 were measured in a third experiment using adults of S. undulatus subjected to full or zero ration with or without re-feeding. In all experiments, plasma corticosterone was measured as an anticipated indicator of nutritional stress. In S. jarrovii, growth and body condition were reduced but lizards remained in positive energy balance on 1/3 ration, and hepatic IGF-1 mRNA and plasma corticosterone were not affected in comparison to full ration. In S. undulatus, growth, body condition, hepatic IGF-1 mRNA, and plasma IGF-1 were all reduced by zero ration and restored by refeeding. Plasma corticosterone was increased in response to zero ration and restored by full ration in hatchlings but not adults of S. undulatus. These data indicate that lizards conform to the broader vertebrate model in which severe food deprivation and negative energy balance is required to attenuate systemic IGF-1 expression. However, when animals remain in positive energy balance, reduced food intake does not appear to affect systemic IGF-1. Consistent with other studies on lizards, the corticosterone response to reduced food intake is an unreliable indicator of nutritional stress. Further studies on ecologically relevant variation in food intake are required to establish the importance of nutrition as an environmental regulator of the GH/IGF axis. Within the range of positive energy balance, the potential involvement of molecular signals in growth regulation requires further investigation. Copyright © 2015 Elsevier Inc. All rights reserved.

Pod-1/Capsulin shows a sex- and stage-dependent expression pattern in the mouse gonad development and represses expression of Ad4BP/SF-1.

PubMed

Tamura, M; Kanno, Y; Chuma, S; Saito, T; Nakatsuji, N

2001-04-01

Mammalian sex-determination and differentiation are controlled by several genes, such as Sry, Sox-9, Dax-1 and Mullerian inhibiting substance (MIS), but their upstream and downstream genes are largely unknown. Ad4BP/SF-1, encoding a zinc finger transcription factor, plays important roles in gonadogenesis. Disruption of this gene caused disappearance of the urogenital system including the gonad. Ad4BP/SF-1, however, is also involved in the sex differentiation of the gonad at later stages, such as the regulation of steroid hormones and MIS. Pod-1/Capsulin, a member of basic helix-loop-helix transcription factors, is expressed in a pattern closely related but mostly complimentary to that of the Ad4BP/SF-1 expression in the developing gonad. In the co-transfection experiment using cultured cells, overexpression of Pod-1/Capsulin repressed expression of a reporter gene that carried the upstream regulatory region of the Ad4BP/SF-1 gene. Furthermore, forced expression of Pod-1/Capsulin repressed expression of Ad4BP/SF-1 in the Leydig cell-derived I-10 cells. These results suggest that Pod-1/Capsulin may play important roles in the development and sex differentiation of the mammalian gonad via transcriptional regulation of Ad4BP/SF-1.

Transcriptomic information from Pacific white shrimp (Litopenaeus vannamei) ovary and eyestalk, and expression patterns for genes putatively involved in the reproductive process.

PubMed

Ventura-López, Claudia; Galindo-Torres, Pavel E; Arcos, Fabiola G; Galindo-Sánchez, Clara; Racotta, Ilie S; Escobedo-Fregoso, Cristina; Llera-Herrera, Raúl; Ibarra, Ana M

2017-05-15

The increased use of massive sequencing technologies has enabled the identification of several genes known to be involved in different mechanisms associated with reproduction that so far have only been studied in vertebrates and other model invertebrate species. In order to further investigate the genes involved in Litopenaeus vannamei reproduction, cDNA and SSH libraries derived from female eyestalk and gonad were produced, allowing the identification of expressed sequences tags (ESTs) that potentially have a role in the regulation of gonadal maturation. In the present study, different transcripts involved in reproduction were identified and a number of them were characterized as full-length. These transcripts were evaluated in males and females in order to establish their tissue expression profiles during developmental stages (juvenile, subadult and adult), and in the case of females, their possible association with gonad maturation was assessed through expression analysis of vitellogenin. The results indicated that the expression of vitellogenin receptor (vtgr) and minichromosome maintenance (mcm) family members in the female gonad suggest an important role during previtellogenesis. Additionally, the expression profiles of genes such as famet, igfbp and gpcr in brain tissues suggest an interaction between the insulin/insulin-like growth factor signaling pathway (IIS) and methyl farnesoate (MF) biosynthesis for control of reproduction. Furthermore, the specific expression pattern of farnesoic acid O-methyltransferase suggests that final synthesis of MF is carried out in different target tissues, where it is regulated by esterase enzymes under a tissue-specific hormonal control. Finally, the presence of a vertebrate type steroid receptor in hepatopancreas and intestine besides being highly expressed in female gonads, suggest a role of that receptor during sexual maturation. Copyright © 2016 Elsevier Inc. All rights reserved.

Expression of deep brain photoreceptors in the Pekin drake: a possible role in the maintenance of testicular function

PubMed Central

Haas, R.; Alenciks, E.; Meddle, S.; Fraley, G. S.

2017-01-01

Abstract Several putative deep brain photoreceptors (DBPs) have been identified, such as melanopsin, opsin 5, and vertebrate ancient opsin. The aim of this study was to elucidate the role of DBPs in gonadal regulation in the Pekin drake. As previously reported, we observed opsin-like immunoreactivity (-ir) in the lateral septum (LS), melanopsin-ir in the premammillary nucleus (PMM), and opsin 5-ir in the periventricular organ. To determine the sensitivity of the DBPs to specific wavelengths of light, drakes were given an acute exposure to red, blue, or white light. Blue light stimulated an increase (P < 0.01) in the immediate early gene fra-2-ir co-expression in melanopsin-ir neurons in the PMM, and red light increased (P < 0.05) fra-2-ir co-expression in opsin-ir neurons, suggesting these neurons are blue- and red-receptive, respectively. To further investigate this photoperiodic response, we exposed drakes to chronic red, long-day white, short-day white, or blue light. Blue light elicited gonadal regression, as testes weight (P < 0.001) and plasma luteinizing hormone (LH) levels (P < 0.001) were lower compared to drakes housed under long-day white light. Photo-regressed drakes experienced complete gonadal recrudescence when housed under long-day red and blue light. qRT-PCR analyses showed that gonadally regressed drakes showed reduced levels (P < 0.01) of gonadotropin releasing hormone (GnRH) mRNA but not photoreceptor or GnIH mRNAs compared to gonadally functional drakes. Our data suggest DBP in the LS may be rhodosin and multiple DBPs are required to fully maintain gonadal function in Pekin drakes. PMID:28339754

The role of fatty acids and triglycerides in the gonads of Paracentrotus lividus from Sardinia: Growth, reproduction and cold acclimatization.

PubMed

Sanna, Roberta; Siliani, Silvia; Melis, Riccardo; Loi, Barbara; Baroli, Maura; Roggio, Tonina; Uzzau, Sergio; Anedda, Roberto

2017-09-01

A detailed characterization of lipid extracts from gonads of P. lividus over a year has been performed combining GC and NMR measurements. For this purpose, sea urchins from two different Sardinian coastal areas were collected monthly. The results underlined a correlation between gonad fatty acids profiles and both water temperature and reproduction process. In particular, EPA and ARA appear to be the most altered fatty acids following seasonal changes. It is suggested that EPA could represent a biomarker of reproduction, reaching a content around 14% during gametogenesis, mainly due to an increase of the sn-1,3 position in TAGs. On the contrary, ARA seems to play a more important role in response to cold acclimatization, which is reflected in a modulation of ARA content in the sn-1,3 position in TAGs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Germ cells are not the primary factor for sexual fate determination in goldfish.

PubMed

Goto, Rie; Saito, Taiju; Takeda, Takahiro; Fujimoto, Takafumi; Takagi, Misae; Arai, Katsutoshi; Yamaha, Etsuto

2012-10-01

The presence of germ cells in the early gonad is important for sexual fate determination and gonadal development in vertebrates. Recent studies in zebrafish and medaka have shown that a lack of germ cells in the early gonad induces sex reversal in favor of a male phenotype. However, it is uncertain whether the gonadal somatic cells or the germ cells are predominant in determining gonadal fate in other vertebrate. Here, we investigated the role of germ cells in gonadal differentiation in goldfish, a gonochoristic species that possesses an XX-XY genetic sex determination system. The primordial germ cells (PGCs) of the fish were eliminated during embryogenesis by injection of a morpholino oligonucleotide against the dead end gene. Fish without germ cells showed two types of gonadal morphology: one with an ovarian cavity; the other with seminiferous tubules. Next, we tested whether function could be restored to these empty gonads by transplantation of a single PGC into each embryo, and also determined the gonadal sex of the resulting germline chimeras. Transplantation of a single GFP-labeled PGC successfully produced a germline chimera in 42.7% of the embryos. Some of the adult germline chimeras had a developed gonad on one side that contained donor derived germ cells, while the contralateral gonad lacked any early germ cell stages. Female germline chimeras possessed a normal ovary and a germ-cell free ovary-like structure on the contralateral side; this structure was similar to those seen in female morphants. Male germline chimeras possessed a testis and a contralateral empty testis that contained some sperm in the tubular lumens. Analysis of aromatase, foxl2 and amh expression in gonads of morphants and germline chimeras suggested that somatic transdifferentiation did not occur. The offspring of fertile germline chimeras all had the donor-derived phenotype, indicating that germline replacement had occurred and that the transplanted PGC had rescued both female and male gonadal function. These findings suggest that the absence of germ cells did not affect the pathway for ovary or testis development and that phenotypic sex in goldfish is determined by somatic cells under genetic sex control rather than an interaction between the germ cells and somatic cells. Copyright © 2012 Elsevier Inc. All rights reserved.

Lizard activity and abundance greater in burned habitat of a xeric montane forest

USGS Publications Warehouse

Fouts, Kevin L.; Moore, Clinton; Johnson, Kristine D.; Maerz, John C.

2017-01-01

Restoring the natural or historical state of ecosystems is a common objective among resource managers, but determining whether desired system responses to management actions are occurring is often protracted and challenging. For wildlife, the integration of mechanistic habitat modeling with population monitoring may provide expedited measures of management effectiveness and improve understanding of how management actions succeed or fail to recover populations. Southern Appalachia is a region of high biodiversity that has undergone dramatic change as a result of human activities such as historic logging, exotic invasions, and alteration of disturbance regimes—including reduction in application of fire. Contemporary efforts to restore fire-maintained ecosystems within southern Appalachian forests require tools to assess the effects of fire management practices on individual animal fitness and relate them to corresponding influences on species abundance. Using automated sensing equipment, we investigated the effects of burned forests on reptile habitat suitability within the western portion of Great Smoky Mountains National Park, Tennessee. Specifically, we used microclimate measurements to model northern fence lizard Sceloporus undulatus hyacinthinus diurnal activity budgets in unburned and variable burn age (3–27-y) forest stands. We estimated northern fence lizard occurrence and abundance along transects through burned and unburned forests. Burned forest stands had microclimates that resulted in longer modeled daily activity periods under most conditions during summer. S. undulatus abundance was 4.75 times greater on burned stands compared to paired unburned stands, although the relationship between burn age and abundance was not well determined. Results suggest the more open habitat structure of burned areas within these xeric pine–oak forests may benefit S. undulatus.

Effects of incubation temperature and estrogen exposure on aromatase activity in the brain and gonads of embryonic alligators.

PubMed Central

Milnes, Matthew R; Roberts, Robert N; Guillette, Louis J

2002-01-01

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 differentiation of species that exhibit temperature-dependent sex determination (TSD). During the temperature-sensitive period (TSP) of sex determination, we compared aromatase activity in the brain and gonads of putative male and female alligator embryos to determine if aromatase activity in the embryonic brain could provide the hormonal environment necessary for ovarian development in a TSD species. In addition, we assessed the pattern of aromatase activity in the brain and gonads of embryos treated with estradiol-17beta (E(2)) and incubated at male-producing temperatures to compare enzyme activity in E(2) sex-reversed females to control males and females. This has particular significance regarding wildlife species living in areas contaminated with suspected environmental estrogens. Gonadal aromatase activity remained low during the early stages of the TSP in both sexes and increased late in the TSP only in females. Aromatase activity in the brain increased prior to gonadal differentiation in both sexes. These results suggest that aromatase activity in the brain is not directly responsible for mediating differentiation of the gonad. E(2) exposure at male-producing temperatures resulted in sex-reversed females that had intermediate gonad function and masculinized brain activity. This study indicates the need to examine multiple end points and to determine the persistence of developmental alterations in contaminant-exposed wildlife populations. PMID:12060834

Expression profiles of three types of GnRH during sex-change in the protandrous cinnamon clownfish, Amphiprion melanopus: Effects of exogenous GnRHs.

PubMed

Kim, Na Na; Shin, Hyun Suk; Habibi, Hamid R; Lee, Jehee; Choi, Cheol Young

2012-02-01

Gonadotropin-releasing hormones (GnRHs) play pivotal roles in the control of reproduction and gonadal maturation in teleost fish. Fish have multiple GnRH genes that encode structurally distinct peptides. We identified salmon GnRH (sGnRH), seabream GnRH (sbGnRH), and chicken GnRH-II (cGnRH-II) by cDNA cloning in cinnamon clownfish (Amphiprion melanopus) using reverse transcription-PCR (RT-PCR) and rapid amplification of cDNA ends-PCR (RACE-PCR). Gene identity was confirmed by sequence alignment and subsequent phylogenetic analyses. We also investigated GnRH mRNA expression in the gonads by quantitative real time-PCR (Q-PCR), and measured plasma estradiol-17β (E(2)) levels in immature fish following treatment with the three molecular forms of GnRHs. The expression levels of sGnRH, sbGnRH, and cGnRH-II mRNA were higher in mature testes and ovaries, as compared to the levels in gonads at earlier stages of maturity. The levels of the three prepro-GnRH mRNA species and the plasma E(2) levels increased after injection of the three GnRH variants. These findings support the hypothesis that GnRH peptides play important roles in the regulation of the hypothalamic-pituitary-gonadal axis and are probably involved in paracrine control of gonadal development and sex change in cinnamon clownfish. Copyright © 2011 Elsevier Inc. All rights reserved.

Unconventional Cadherin Localization in Honey Bee Gonads Revealed Through Domain-Specific Apis mellifera E- and N-Cadherin Antibodies Indicates Alternative Functions

PubMed Central

Florecki, Mônica M.; Hartfelder, Klaus

2012-01-01

As key factors in intercellular adhesion processes, cadherins play important roles in a plethora of developmental processes, including gametogenesis. In a previous study on cadherin localization in the gonads of honey bees, performed with heterologous pan-cadherin antibodies, we detected these proteins as (i) associated with cell membranes, (ii) as homogeneously distributed throughout the cytoplasm, and (iii) as nuclear foci in both somatic and germline cells, raising the possibility of alternative functions. To further investigate such unusual intracellular cadherin localization we produced specific antibodies against the N- and C-terminal domains of honey bee N- and E-cadherin. A 160 kDa protein was recognized by the E-cadherin antibodies as well as one of approximately 300 kDa from those raised against N-cadherin. In gonad preparations, both proteins were detected as dispersed throughout the cytoplasm and as nuclear foci in both germline and somatic cells of queen and worker ovarioles, as well as in the testioles of drones. This leads us to infer that cadherins may indeed be involved in certain signaling pathways and/or transcriptional regulation during gametogenesis. In late oogenesis stages, immunolabeling for both proteins was observed at the cell cortex, in conformity with a role in cell adhesion. In testioles, E-cadherin was seen in co-localization with fusomes, indicating a possible role in cyst organization. Taken together, the distribution of N- and E-cadherins in honey bee gonads is suggestive of alternative roles for cadherins in gametogenesis of both sexes. PMID:26466735

Unconventional Cadherin Localization in Honey Bee Gonads Revealed Through Domain-Specific Apis mellifera E- and N-Cadherin Antibodies Indicates Alternative Functions.

PubMed

Florecki, Mônica M; Hartfelder, Klaus

2012-11-22

As key factors in intercellular adhesion processes, cadherins play important roles in a plethora of developmental processes, including gametogenesis. In a previous study on cadherin localization in the gonads of honey bees, performed with heterologous pan-cadherin antibodies, we detected these proteins as (i) associated with cell membranes, (ii) as homogeneously distributed throughout the cytoplasm, and (iii) as nuclear foci in both somatic and germline cells, raising the possibility of alternative functions. To further investigate such unusual intracellular cadherin localization we produced specific antibodies against the N- and C-terminal domains of honey bee N- and E-cadherin. A 160 kDa protein was recognized by the E-cadherin antibodies as well as one of approximately 300 kDa from those raised against N-cadherin. In gonad preparations, both proteins were detected as dispersed throughout the cytoplasm and as nuclear foci in both germline and somatic cells of queen and worker ovarioles, as well as in the testioles of drones. This leads us to infer that cadherins may indeed be involved in certain signaling pathways and/or transcriptional regulation during gametogenesis. In late oogenesis stages, immunolabeling for both proteins was observed at the cell cortex, in conformity with a role in cell adhesion. In testioles, E-cadherin was seen in co-localization with fusomes, indicating a possible role in cyst organization. Taken together, the distribution of N- and E-cadherins in honey bee gonads is suggestive of alternative roles for cadherins in gametogenesis of both sexes.

Physiological roles of STIM1 and Orai1 homologs and CRAC channels in the genetic model organism Caenorhabditis elegans

PubMed Central

Strange, Kevin; Yan, Xiaohui; Lorin-Nebel, Catherine; Xing, Juan

2007-01-01

Summary The nematode Caenorhabditis elegans provides numerous experimental advantages for developing an integrative molecular understanding of physiological processes and has proven to be a valuable model for characterizing Ca2+ signaling mechanisms. This review will focus on the role of Ca2+ release activated Ca2+ (CRAC) channel activity in function of the worm gonad and intestine. Inositol 1,4,5-trisphosphate (IP3)-dependent oscillatory Ca2+ signaling regulates contractile activity of the gonad and rhythmic posterior body wall muscle contraction (pBoc) required for ovulation and defecation, respectively. The C. elegans genome contains a single homolog of both STIM1 and Orai1, proteins required for CRAC channel function in mammalian and Drosophila cells. C. elegans STIM-1 and ORAI-1 are coexpressed in the worm gonad and intestine and give rise to robust CRAC channel activity when coexpressed in HEK293 cells. STIM-1 or ORAI-1 knockdown causes complete sterility demonstrating that the genes are essential components of gonad Ca2+ signaling. Knockdown of either protein dramatically inhibits intestinal cell CRAC channel activity, but surprisingly has no effect on pBoc, intestinal Ca2+ oscillations or intestinal ER Ca2+ store homeostasis. CRAC channels thus do not play obligate roles in all IP3-dependent signaling processes in C. elegans. Instead, we suggest that CRAC channels carry out highly specialized and cell specific signaling roles and that they may function as a failsafe mechanism to prevent Ca2+ store depletion under pathophysiological and stress conditions. PMID:17376526

Mycobacteriosis due to Mycobacterium genavense in six pet birds.

PubMed Central

Hoop, R K; Böttger, E C; Ossent, P; Salfinger, M

1993-01-01

Six cases of mycobacteriosis due to Mycobacterium genavense in three budgerigars (Melopsittacus undulatus), one orange-winged amazon (Amazona amazonica), one flycatcher (Cyanoptila cyanomelana), and one zebra finch (Taeniopygia guttata) are discussed. Gross lesions associated with the infection included a high degree of muscular wasting (five cases), hepatomegaly (four cases), and thickening of the wall of the small intestine (four cases). Granulomas were found in the lung (one case) and the subcutis (one case). Acid-fast bacilli were detected in the liver of all six birds. Only the use of acidic BACTEC mediums consistently led to growth, whereas the egg-based medium failed. These findings point to a possible role of the environment as a reservoir for M. genavense. Images PMID:8463407

Investigation and control of an attaching and effacing Escherichia coli outbreak in a colony of captive budgerigars (Melopsittacus undulatus).

PubMed

Seeley, Kathryn E; Baitchman, Eric; Bartlett, Susan; DebRoy, Chitrita; Garner, Michael M

2014-12-01

An increase in mortality in a captive flock of budgerigars (Melopsittacus undulatus) coincided with the isolation of attaching and effacing Escherichia coli from postmortem samples. Common histologic lesions included hepatitis, enteritis, and in one case attaching and effacing lesions along the intestinal tract. Retrospective review of necropsy records and increased sampling led to the identification of several cases of E. coli with the attaching and effacing (eae) virulence gene. Factors such as environment, nutrition, and concomitant pathogens were thought to contribute to mortality in the flock. Although it is not clear whether E. coli was a primary pathogen during the period of increased mortality, the presence of the eae gene combined with associated histologic lesions supports the conclusion that this organism was a significant contributor to mortality. Manipulation of diet, environment, and the addition of probiotic supplementation resulted in a decline in mortality rate and decreased shedding of E. coli based on negative follow-up cultures of intestines, liver, and feces.

Effects of two diets on the haematology, plasma chemistry and intestinal flora of budgerigars (Melopsittacus undulatus).

PubMed

Fischer, I; Christen, C; Lutz, H; Gerlach, H; Hässig, M; Hatt, J-M

2006-10-07

Two groups of 22 budgerigars (Melopsittacus undulatus) were housed for 12 months under identical conditions. One group was fed a commercial seed mixture plus carrots and a mineral supplement, and the other group was fed a commercially formulated diet plus carrots. Samples of blood and faeces were collected initially and after three, six, nine and 12 months. There were no significant differences between the haematological values of the two groups. The group fed the seed mixture had significantly higher concentrations of glucose, albumin, triglycerides and uric acid, and higher activity of aspartate aminotransferase, but the values were within the published reference ranges for normal birds. There were no significant differences between the faecal samples from the two groups, except that the fungus Macrorhabdus ornithogaster was identified in 48.3 per cent of the samples from the group fed the commercially formulated diet but from only 3.4 per cent of the samples from the group fed the seed mixture.

Environmental sex determination mechanisms in reptiles.

PubMed

Merchant-Larios, H; Díaz-Hernández, V

2013-01-01

Temperature-dependent sex determination (TSD) was first discovered in reptiles. Since then, a great diversity of sex-determining responses to temperature has been reported. Higher temperatures can produce either males or females, and the temperature ranges and lengths of exposure that influence TSD are remarkably variable among species. In addition, transitory gene regulatory networks leading to gonadal TSD have evolved. Although most genes involved in gonadal development are conserved in vertebrates, including TSD species, temporal and spatial gene expression patterns vary among species. Despite variation in TSD pattern and gene expression heterochrony, the structural framework, the medullary cords, and cortex of the bipotential gonad have been strongly conserved. Aromatase (CYP19), which regulates gonadal estrogen levels, is proposed to be the main target of a putative thermosensitive factor for TSD. However, manipulation of estrogen levels rarely mimics the precise timing of temperature effects on expression of gonadal genes, as occurs with TSD. Estrogen levels may influence sex determination or gonad differentiation depending on the species. Furthermore, the process leading to sex determination under the influence of temperature poses problems that are not encountered by species with genetic sex determination. Yolk steroids of maternal origin and steroids produced by the embryonic nervous system should also be considered as sources of hormones that may play a role in TSD. Copyright © 2012 S. Karger AG, Basel.

X and Y Chromosome Complement Influence Adiposity and Metabolism in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Itoh, Yuichiro; Reue, Karen

2013-01-01

Three different models of MF1 strain mice were studied to measure the effects of gonadal secretions and sex chromosome type and number on body weight and composition, and on related metabolic variables such as glucose homeostasis, feeding, and activity. The 3 genetic models varied sex chromosome complement in different ways, as follows: 1) “four core genotypes” mice, comprising XX and XY gonadal males, and XX and XY gonadal females; 2) the XY* model comprising groups similar to XO, XX, XY, and XXY; and 3) a novel model comprising 6 groups having XO, XX, and XY chromosomes with either testes or ovaries. In gonadally intact mice, gonadal males were heavier than gonadal females, but sex chromosome complement also influenced weight. The male/female difference was abolished by adult gonadectomy, after which mice with 2 sex chromosomes (XX or XY) had greater body weight and percentage of body fat than mice with 1 X chromosome. A second sex chromosome of either type, X or Y, had similar effects, indicating that the 2 sex chromosomes each possess factors that influence body weight and composition in the MF1 genetic background. Sex chromosome complement also influenced metabolic variables such as food intake and glucose tolerance. The results reveal a role for the Y chromosome in metabolism independent of testes and gonadal hormones and point to a small number of X–Y gene pairs with similar coding sequences as candidates for causing these effects. PMID:23397033

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

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.

Hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes: sex differences in regulation of stress responsivity.

PubMed

Oyola, Mario G; Handa, Robert J

2017-09-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism's response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic-pituitary-gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life.

Hypothalamic–pituitary–adrenal and hypothalamic–pituitary–gonadal axes: sex differences in regulation of stress responsivity

PubMed Central

Oyola, Mario G.; Handa, Robert J.

2018-01-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic–pituitary–adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism’s response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic–pituitary–gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life. PMID:28859530

Sex differences and hormonal modulation of deep tissue pain

PubMed Central

Traub, Richard J.; Ji, Yaping

2013-01-01

Women disproportionately suffer from many deep tissue pain conditions. Experimental studies show that women have lower pain thresholds, higher pain ratings and less tolerance to a range of painful stimuli. Most clinical and epidemiological reports suggest female gonadal hormones modulate pain for some, but not all, conditions. Similarly, animal studies support greater nociceptive sensitivity in females in many deep tissue pain models. Gonadal hormones modulate responses in primary afferents, dorsal horn neurons and supraspinal sites, but the direction of modulation is variable. This review will examine sex differences in deep tissue pain in humans and animals focusing on the role of gonadal hormones (mainly estradiol) as an underlying component of the modulation of pain sensitivity. PMID:23872333

Hormonal Regulation of Extinction: Implications for Gender Differences in the Mechanisms of PTSD

DTIC Science & Technology

2010-03-01

Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT This project investigates the role of gonadal hormones in the regulation of Pavlovian fear conditioning ...and its extinction. Pavlovian fear conditioning and its extinction serve as an animal model for the development of pathological fear in humans that...gonadal hormones in the regulation of Pavlovian fear conditioning and its extinction. Pavlovian fear conditioning and its extinction serve as an animal

Specific Roles for 17ß-Estradiol versus Gonad Development in Nutrient Partitioning and Regulation of Nutrient- and Growth-Related Mechanisms During Sexual Maturation in Rainbow Trout

USDA-ARS?s Scientific Manuscript database

The contribution of sex steroids to nutrient partitioning and energy balance during gonad development was studied in rainbow trout (Oncorhynchus mykiss). Nineteen month old triploid (3N) female rainbow trout were fed a diet supplemented with 17ß-estradiol (E2) at 30 mg steroid/kg diet for a 1 month...

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. (c) 2009 Wiley-Liss, Inc.

Potential contributions of heat shock proteins to temperature-dependent sex determination in the American alligator.

PubMed

Kohno, S; Katsu, Y; Urushitani, H; Ohta, Y; Iguchi, T; Guillette, L J

2010-01-01

Sex determination in the American alligator depends on the incubation temperature experienced during a thermo-sensitive period (TSP), although sex determination can be 'reversed' by embryonic exposure to an estrogenic compound. Thus, temperature and estrogenic signals play essential roles during temperature-dependent sex determination (TSD). The genetic basis for TSD is poorly understood, although previous studies observed that many of the genes associated with genetic sex determination (GSD) are expressed in species with TSD. Heat shock proteins (HSPs), good candidates because of their temperature-sensitive expression, have not been examined in regard to TSD but HSPs have the ability to modify steroid receptor function. A number of HSP cDNAs (HSP27, DNAJ, HSP40, HSP47, HSP60, HSP70A, HSP70B, HSP70C, HSP75, HSP90alpha, HSP90beta, and HSP108) as well as cold-inducible RNA binding protein (CIRBP) and HSP-binding protein (HSPBP) were cloned, and expression of their mRNA in the gonadal-adrenal-mesonephros complex (GAM) was investigated. Embryonic and neonatal GAMs exhibited mRNA for all of the HSPs examined during and after the TSP. One-month-old GAMs were separated into 3 portions (gonad, adrenal gland, and mesonephros), and sexual dimorphism in the mRNA expression of gonadal HSP27 (male > female), gonadal HSP70A (male < female), and adrenal HSP90 alpha (male > female) was observed. These findings provide new insights on TSD and suggest that further studies examining the role of HSPs during gonadal development are needed. (c) 2009 S. Karger AG, Basel.

Gonadal steroids regulate the expression of aggrecanases in human endometrial stromal cells in vitro

PubMed Central

Wen, Jiadi; Zhu, Hua; Leung, Peter CK

2013-01-01

The human endometrium undergoes cyclic change during each menstrual cycle in response to gonadal steroids. Proteolysis of endometrial extracellular matrix (ECM) is necessary to prepare this dynamic tissue for pregnancy. Proteolytic enzymes such as matrix metalloproteinase (MMP) and closely related a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been assigned key roles in the highly regulated cyclic remodelling of the endometrial ECM. We have previously shown that ADAMTS-1 undergoes spatiotemporal changes in human endometrial stromal cells under the regulation of gonadal steroids. This suggests that other ADAMTS subtypes, known as aggrecanases, may contribute to the ECM remodelling events that occur in female physiological cycles and in preparation for pregnancy. To determine whether progesterone (P4), 17β-estradiol (E2), or dihydrotestosterone (DHT), alone or in combination, are capable of regulating ADAMTS-4, -5, -8 or -9 expression in human endometrial stromal cells in vitro. Real-time quantitative PCR and Western blot analysis were used to measure ADAMTSs mRNA and protein levels in primary cultures of human endometrial stromal cells (n = 12). P4, DHT but not E2 have regulatory effects on ADAMTS-8, -9 and -5 expression. Combined treatment with gonadal steroids did not show any synergistic or antagonistic effects. However, the synthetic steroid antagonists RU486 and hydroxyflutamide specifically inhibited the P4- or DHT-mediated regulatory effects on ADAMTS expression. These studies provide evidence that the regulation of aggrecanases by gonadal steroids in human endometrial stromal cells may play an important role during decidualization. PMID:23947778

A Novel igf3 Gene in Common Carp (Cyprinus carpio): Evidence for Its Role in Regulating Gonadal Development.

PubMed

Song, Feibiao; Wang, Lanmei; Zhu, Wenbin; Fu, Jianjun; Dong, Juanjuan; Dong, Zaijie

2016-01-01

Since the insulin-like growth factor 3 (igf3) gene was recently discovered in fish ovary, its function in the gonads has received much attention. In this study, we isolated two igf3 subtypes from common carp (Cyprinus carpio), which comprised full-length cDNA of 707 and 1153 nucleotides encoding 205 and 198 amino acids (aa), respectively. The Igf3 aa sequence had the highest gene homology of 72% with the corresponding sequence in zebrafish (Danio rerio). Phylogenetic tree construction revealed that the C. carpio igf3 gene was first clustered with D. rerio and then with other teleost species. Igf3 mRNA was widely expressed, with expression being highest in the gonads and blood. In the gonad development stage, igf3a mRNA expression was highest in the maturity and recession stage of the ovary, and decline phase of the testis, while igf3b was highest in the recession and fully mature periods of the ovaries and testes, respectively. Western blotting of testis protein samples showed two bands of approximately 21 kDa and 34 kDa corresponding to the calculated molecular mass of the two Igf3 subtypes; no signal was detected in the ovary. The Igf3 protein was localized in the ovary granulosa cells and testis spermatogonium and spermatids. 17β-Ethinylestradiol treatment increased both ovary and testis igf3 mRNA expression. These findings suggest that Igf3 may play an important role in C. carpio gonadal development.

A Novel igf3 Gene in Common Carp (Cyprinus carpio): Evidence for Its Role in Regulating Gonadal Development

PubMed Central

Zhu, Wenbin; Fu, Jianjun; Dong, Juanjuan; Dong, Zaijie

2016-01-01

Since the insulin-like growth factor 3 (igf3) gene was recently discovered in fish ovary, its function in the gonads has received much attention. In this study, we isolated two igf3 subtypes from common carp (Cyprinus carpio), which comprised full-length cDNA of 707 and 1153 nucleotides encoding 205 and 198 amino acids (aa), respectively. The Igf3 aa sequence had the highest gene homology of 72% with the corresponding sequence in zebrafish (Danio rerio). Phylogenetic tree construction revealed that the C. carpio igf3 gene was first clustered with D. rerio and then with other teleost species. Igf3 mRNA was widely expressed, with expression being highest in the gonads and blood. In the gonad development stage, igf3a mRNA expression was highest in the maturity and recession stage of the ovary, and decline phase of the testis, while igf3b was highest in the recession and fully mature periods of the ovaries and testes, respectively. Western blotting of testis protein samples showed two bands of approximately 21 kDa and 34 kDa corresponding to the calculated molecular mass of the two Igf3 subtypes; no signal was detected in the ovary. The Igf3 protein was localized in the ovary granulosa cells and testis spermatogonium and spermatids. 17β-Ethinylestradiol treatment increased both ovary and testis igf3 mRNA expression. These findings suggest that Igf3 may play an important role in C. carpio gonadal development. PMID:28002497

Identification of multiple dmrt1s in catfish: localization, dimorphic expression pattern, changes during testicular cycle and after methyltestosterone treatment.

PubMed

Raghuveer, K; Senthilkumaran, B

2009-05-01

The double sex and mab-3 related (DM) transcription factor 1 (dmrt1) plays an important role in testicular differentiation. Here, we report cloning of multiple dmrt1s, a full-length and two alternative spliced forms from adult catfish (Clarias gariepinus) testis, which encode predicted proteins of 287 (dmrt1a), 253 (dmrt1b) and 233 (dmrt1c) amino acid residues respectively. Interestingly, dmrt1c lacks the majority of the DM domain. Multiple dmrt1s (dmrt1a and dmrt1c) were obtained from Clarias batrachus as well. Tissue distribution (transcript and protein) of catfish dmrt1 revealed exclusive expression in testis. Semi-quantitative RT-PCR revealed the presence of multiple dmrt1s with high levels of dmrt1a in adult testis but not in ovary. Real-time RT-PCR analysis during testicular cycle showed higher levels of dmrt1 transcripts in preparatory and pre-spawning when compared with spawning and post-spawning phases. Immunocytochemical and immunofluorescence localization revealed the presence of catfish Dmrt1 protein in spermatogonia and spermatocytes, which indicates plausible role in spermatogenesis. Histological analysis indicated initiation of gonadal sex differentiation in catfish around 40-50 days after hatching. The potential role for dmrt1 in testicular differentiation is evident from its stage-dependent elevated expression in developing testis. Furthermore, dimorphic expressions of dmrt1s were evident at different stages of gonadal development or recrudescence in catfish. Treatment of methyl testosterone (MT) during early stages of gonadal sex differentiation resulted in adult males. Interestingly, we also obtained MT-treated fishes having ova-testis gonads. Analysis of dmrt1, sox9a, foxl2 and cyp19a1 expression patterns in MT-treated gonads revealed tissue-specific pattern. These results together suggest that multiple dmrt1s are testis-specific markers in catfish.

DAX1/NR0B1 was expressed during mammalian gonadal development and gametogenesis before it was recruited to the eutherian X chromosome.

PubMed

Stickels, Robert; Clark, Kevin; Heider, Thomas N; Mattiske, Deidre M; Renfree, Marilyn B; Pask, Andrew J

2015-01-01

The nuclear receptor subfamily 0, group B, member 1 (NR0B1) gene is an orphan nuclear receptor that is X-linked in eutherian mammals and plays a critical role in the establishment and function of the hypothalamic-pituitary-adrenal-gonadal axis. Duplication or overexpression of NR0B1 in eutherian males causes male to female sex reversal, and mutation and deletions of NR0B1 cause testicular defects. Thus, gene dosage is critical for the function of NR0B1 in normal gonadogenesis. However, NR0B1 is autosomal in all noneutherian vertebrates, including marsupials and monotreme mammals, and two active copies of the gene are compatible with both male and female gonadal development. In the current study, we examined the evolution and expression of autosomal NR0B1 during gonadal development in a marsupial (the tammar wallaby) as compared to the role of its X-linked orthologues in a eutherian (the mouse). We show that NR0B1 underwent rapid evolutionary change when it relocated from its autosomal position in the nonmammalian vertebrates, monotremes, and marsupials to an X-linked location in eutherian mammals. Despite the acquisition of a novel genomic location and a unique N-terminal domain, NR0B1 protein distribution was remarkably similar between mice and marsupials both throughout gonadal development and during gamete formation. A conserved accumulation of NR0B1 protein was observed in developing oocytes, where its function appears to be critical in the early embryo, prior to zygotic genome activation. Together these findings suggest that NR0B1 had a conserved role in gonadogenesis that existed long before it moved to the X chromosome and despite undergoing significant evolutionary change. © 2015 by the Society for the Study of Reproduction, Inc.

A role for glucocorticoids in stress-impaired reproduction: beyond the hypothalamus and pituitary.

PubMed

Whirledge, Shannon; Cidlowski, John A

2013-12-01

In addition to the well-characterized role of the sex steroid receptors in regulating fertility and reproduction, reproductive events are also mediated by the hypothalamic-pituitary-adrenal axis in response to an individual's environment. Glucocorticoid secretion in response to stress contributes to the well-characterized suppression of the hypothalamic-pituitary-gonadal axis through central actions in the hypothalamus and pituitary. However, both animal and in vitro studies indicate that other components of the reproductive system are also regulated by glucocorticoids. Furthermore, in the absence of stress, it appears that homeostatic glucocorticoid signaling plays a significant role in reproduction and fertility in all tissues comprising the hypothalamic-pituitary-gonadal axis. Indeed, as central regulators of the immune response, glucocorticoids are uniquely poised to integrate an individual's infectious, inflammatory, stress, nutritional, and metabolic status through glucocorticoid receptor signaling in target tissues. Endocrine signaling between tissues regulating the immune and stress response and those determining reproductive status provides an evolutionary advantage, facilitating the trade-off between reproductive investment and offspring fitness. This review focuses on the actions of glucocorticoids in tissues important for fertility and reproduction, highlighting recent studies that show glucocorticoid signaling plays a significant role throughout the hypothalamic-pituitary-gonadal axis and characterizing these effects as permissive or inhibitory in terms of facilitating reproductive success.

A Role for Glucocorticoids in Stress-Impaired Reproduction: Beyond the Hypothalamus and Pituitary

PubMed Central

Whirledge, Shannon

2013-01-01

In addition to the well-characterized role of the sex steroid receptors in regulating fertility and reproduction, reproductive events are also mediated by the hypothalamic-pituitary-adrenal axis in response to an individual's environment. Glucocorticoid secretion in response to stress contributes to the well-characterized suppression of the hypothalamic-pituitary-gonadal axis through central actions in the hypothalamus and pituitary. However, both animal and in vitro studies indicate that other components of the reproductive system are also regulated by glucocorticoids. Furthermore, in the absence of stress, it appears that homeostatic glucocorticoid signaling plays a significant role in reproduction and fertility in all tissues comprising the hypothalamic-pituitary-gonadal axis. Indeed, as central regulators of the immune response, glucocorticoids are uniquely poised to integrate an individual's infectious, inflammatory, stress, nutritional, and metabolic status through glucocorticoid receptor signaling in target tissues. Endocrine signaling between tissues regulating the immune and stress response and those determining reproductive status provides an evolutionary advantage, facilitating the trade-off between reproductive investment and offspring fitness. This review focuses on the actions of glucocorticoids in tissues important for fertility and reproduction, highlighting recent studies that show glucocorticoid signaling plays a significant role throughout the hypothalamic-pituitary-gonadal axis and characterizing these effects as permissive or inhibitory in terms of facilitating reproductive success. PMID:24064362

Sleep, rhythms, and the endocrine brain: influence of sex and gonadal hormones.

PubMed

Mong, Jessica A; Baker, Fiona C; Mahoney, Megan M; Paul, Ketema N; Schwartz, Michael D; Semba, Kazue; Silver, Rae

2011-11-09

While much is known about the mechanisms that underlie sleep and circadian rhythms, the investigation into sex differences and gonadal steroid modulation of sleep and biological rhythms is in its infancy. There is a growing recognition of sex disparities in sleep and rhythm disorders. Understanding how neuroendocrine mediators and sex differences influence sleep and biological rhythms is central to advancing our understanding of sleep-related disorders. While it is known that ovarian steroids affect circadian rhythms in rodents, the role of androgen is less understood. Surprising findings that androgens, acting via androgen receptors in the master "circadian clock" within the suprachiasmatic nucleus, modulate photic effects on activity in males point to novel mechanisms of circadian control. Work in aromatase-deficient mice suggests that some sex differences in photic responsiveness are independent of gonadal hormone effects during development. In parallel, aspects of sex differences in sleep are also reported to be independent of gonadal steroids and may involve sex chromosome complement. This a summary of recent work illustrating how sex differences and gonadal hormones influence sleep and circadian rhythms that was presented at a Mini-Symposium at the 2011 annual meeting of the Society for Neuroscience.

Sleep, Rhythms, and the Endocrine Brain: Influence of Sex and Gonadal Hormones

PubMed Central

Mong, Jessica A.; Baker, Fiona C.; Mahoney, Megan M.; Paul, Ketema N.; Schwartz, Michael D.; Semba, Kazue; Silver, Rae

2011-01-01

While much is known about the mechanisms that underlie sleep and circadian rhythms, the investigation into sex differences and gonadal steroid modulation of sleep and biological rhythms is in its infancy. There is a growing recognition of sex disparities in sleep and rhythm disorders. Understanding how neuroendocrine mediators and sex differences influence sleep and biological rhythms is central to advancing our understanding of sleep-related disorders. While it is known that ovarian steroids affect circadian rhythms in rodents, the role of androgen is less understood. Surprising findings that androgens, acting via androgen receptors in the master “circadian clock” within the suprachiasmatic nucleus (SCN), modulate photic effects on activity in males points to novel mechanisms of circadian control. Work in aromatase deficient (ArKO) mice suggests that some sex differences in photic responsiveness are independent of gonadal hormone effects during development. In parallel, aspects of sex differences in sleep are also reported to be independent of gonadal steroids and may involve sex chromosome complement. This a summary of recent work illustrating how sex differences and gonadal hormones influence sleep and circadian rhythms that was presented at a mini-symposium at the 2011 annual meeting of the Society for Neuroscience. PMID:22072663

Cloning and expression analysis of vasa during the reproductive cycle of Korean rockfish, Sebastes schlegeli

NASA Astrophysics Data System (ADS)

Mu, Weijie; Wen, Haishen; He, Feng; Li, Jifang; Liu, Miao; Ma, Ruiqin; Zhang, Yuanqing; Hu, Jian; Qi, Baoxia

2013-03-01

Vasa, which is a conserved member of the DEAD-box protein family, plays an indispensable role in primordial germ cell proliferation. However, the expression of vasa gene during the reproductive cycle in ovoviviparous fish has not been documented. In this study, the full-length sequence of vasa was obtained from the ovary of Korean rockfish ( Sebastes schlegeli) using reverse transcription-PCR and rapid amplification of cDNA ends. The Vasa with a mature protein of 650 amino acids showed greatest homology (84%) with giant gourami ( Osphronemus goramy) and Pacific bluefin tuna ( Thunnus orientalis). The expression of vasa mRNA in Korean rockfish was detected in gonads only, suggesting its specific role in gonadal development. In addition, seasonal changes in the vasa expression levels were examined in gonads by quantitative real-time PCR. The vasa transcript levels in adult testis were found higher during spermatogenesis than during spermiation. The vasa transcript levels remained relatively high at the early ovary stage but declined during ovary maturation in adult female fish. These results suggest that the vasa gene play an important role in spermatogenesis and early oogenesis during the reproductive cycle of Korean rockfish.

Gonadal steroids and bone metabolism in men.

PubMed

Leder, Benjamin

2007-06-01

Over the past decade, our increasing awareness of the clinical importance of osteoporosis in men has stimulated intense interest in trying to better understand male skeletal physiology and pathophysiology. The present review focuses on a major focus of research in this area, namely the attempt to define the influence and therapeutic potential of gonadal steroids in male bone metabolism. Building on previous work defining the relative roles of androgens and estrogens in the developing male skeleton and in maintaining normal bone turnover, recent studies have begun to define these issues from epidemiologic, physiologic and therapeutic perspectives. With access to data from large prospectively defined populations of men, investigators are confirming and challenging existing hypotheses and forwarding new concepts. Clinical trials have expanded beyond standard androgen replacement studies to explore more complex hormonal interventions. Physiologic investigation has continued to probe the mechanisms underlying the differential and independent roles of androgens and estrogens in male bone metabolism. Recent work has added significantly to our understanding of the role of gonadal steroids in male skeletal physiology. Nonetheless, further research is necessary to build on these initial human studies and to capitalize on rapidly emerging advances in our understanding of the basic biology of bone metabolism.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Growth and activity of Sceloporus cowlesi (southwestern fence lizard)

Treesearch

Heather L. Bateman; Alice Chung-MacCoubrey

2012-01-01

Lizards from the Sceloporus undulatus complex have been the subject of many studies on lizard ecology (Hager 2001; Rosenblum 2006; Rosenblum et al. 2007), behavior (Hein and Whitaker 1997; Robertson and Rosenblum 2009), and reproduction (Vinegar 1975; Robertson and Rosenblum 2010). However, genetic data (Leache and Reeder 2002) support reallocation of the subspecies of...

Germ cells in the teleost fish medaka have an inherent feminizing effect

PubMed Central

Nishimura, Toshiya; Yamada, Kazuki; Fujimori, Chika; Kikuchi, Mariko; Kawasaki, Toshihiro; Siegfried, Kellee R.; Sakai, Noriyoshi

2018-01-01

Germ cells give rise to eggs or sperm. However, recent analyses in medaka (Oryzias latipes) showed that germ cells are also important for feminization of gonads, although this novel role of germ cells has not been characterized in detail. Here, we show that the feminizing effect is inherent to germ cells and is not affected by gametogenic stages or the sexual fate of germ cells. Three medaka mutants were generated to demonstrate this effect: figlα mutants, in which follicle formation is disrupted; meioC mutants, in which germ cells are unable to commit to gametogenesis and meiosis; and dazl mutants, in which germ cells do not develop into gonocytes. All these different stages of germ cells in XX mutants have an ability to feminize the gonads, resulting in the formation of gonads with ovarian structures. In addition to normal ovarian development, we also suggest that the increased number of gonocytes is sufficient for male to female sex reversal in XY medaka. These results may genetically demonstrate that the mechanism underlying the feminizing effect of germ cells is activated before the sexual fate decision of germ cells and meiosis, probably by the time of gonocyte formation in medaka. Author summary Germ cells are the only cells that can transfer genetic materials to the next generation via the sperm or egg. However, recent analyses in teleosts revealed another essential role of germ cells: feminizing the gonads. In our study, medaka mutants in which gametogenesis was blocked at specific stages provides the novel view that the feminizing effect of germ cells occurs in parallel with other reproductive elements, such as meiosis, the sexual fate decision of germ cells, and gametogenesis. Germ cells in medaka may have a potential to feminize gonads at the moment they have developed. PMID:29596424

High-Throughput Sequencing Reveals Hypothalamic MicroRNAs as Novel Partners Involved in Timing the Rapid Development of Chicken (Gallus gallus) Gonads.

PubMed

Han, Wei; Zou, Jianmin; Wang, Kehua; Su, Yijun; Zhu, Yunfen; Song, Chi; Li, Guohui; Qu, Liang; Zhang, Huiyong; Liu, Honglin

2015-01-01

Onset of the rapid gonad growth is a milestone in sexual development that comprises many genes and regulatory factors. The observations in model organisms and mammals including humans have shown a potential link between miRNAs and development timing. To determine whether miRNAs play roles in this process in the chicken (Gallus gallus), the Solexa deep sequencing was performed to analyze the profiles of miRNA expression in the hypothalamus of hens from two different pubertal stages, before onset of the rapid gonad development (BO) and after onset of the rapid gonad development (AO). 374 conserved and 46 novel miRNAs were identified as hypothalamus-expressed miRNAs in the chicken. 144 conserved miRNAs were showed to be differentially expressed (reads > 10, P < 0.05) during the transition from BO to AO. Five differentially expressed miRNAs were validated by real-time quantitative RT-PCR (qRT-PCR) method. 2013 putative genes were predicted as the targets of the 15 most differentially expressed miRNAs (fold-change > 4.0, P < 0.01). Of these genes, 7 putative circadian clock genes, Per2, Bmal1/2, Clock, Cry1/2, and Star were found to be targeted multiple times by the miRNAs. qRT-PCR revealed the basic transcription levels of these clock genes were much higher (P < 0.01) in AO than in BO. Further functional analysis suggested that these 15 miRNAs play important roles in transcriptional regulation and signal transduction pathways. The results provide new insights into miRNAs functions in timing the rapid development of chicken gonads. Considering the characteristics of miRNA functional conservation, the results will contribute to the research on puberty onset in humans.

Sex-biased miRNAs in gonad and their potential roles for testis development in yellow catfish.

PubMed

Jing, Jing; Wu, Junjie; Liu, Wei; Xiong, Shuting; Ma, Wenge; Zhang, Jin; Wang, Weimin; Gui, Jian-Fang; Mei, Jie

2014-01-01

Recently, YY super-male yellow catfish had been created by hormonal-induced sex reversal and sex-linked markers, which provides a promising research model for fish sex differentiation and gonad development, especially for testis development. MicroRNAs (miRNAs) have been revealed to play crucial roles in the gene regulation and gonad development in vertebrates. In this study, three small RNA libraries constructed from gonad tissues of XX female, XY male and YY super-male yellow catfish were sequenced. The sequencing data generated a total of 384 conserved miRNAs and 113 potential novel miRNAs, among which 23, 30 and 14 miRNAs were specifically detected in XX ovary, XY testis, and YY testis, respectively. We observed relative lower expression of several miR-200 family members, including miR-141 and miR-429 in YY testis compared with XY testis. Histological analysis indicated a higher degree of testis maturity in YY super-males compared with XY males, as shown by larger spermatogenic cyst, more spermatids and fewer spermatocytes in the spermatogenic cyst. Moreover, five miR-200 family members were significantly up-regulated in testis when treated by 17α-ethinylestradiol (EE2), high dose of which will impair testis development and cell proliferation. The down-regulation of miR-141 and 429 coincides with the progression of testis development in both yellow catfish and human. At last, the expression pattern of nine arbitrarily selected miRNAs detected by quantitative RT-PCR was consistent with the Solexa sequencing results. Our study provides a comprehensive miRNA transcriptome analysis for gonad of yellow catfish with different sex genotypes, and identifies a number of sex-biased miRNAs, some of that are potentially involved in testis development and spermatogenesis.

Age, sex, and gonadal hormones differently influence anxiety- and depression-related behavior during puberty in mice.

PubMed

Boivin, Josiah R; Piekarski, David J; Wahlberg, Jessica K; Wilbrecht, Linda

2017-11-01

Anxiety and depression symptoms increase dramatically during adolescence, with girls showing a steeper increase than boys after puberty onset. The timing of the onset of this sex bias led us to hypothesize that ovarian hormones contribute to depression and anxiety during puberty. In humans, it is difficult to disentangle direct effects of gonadal hormones from social and environmental factors that interact with pubertal development to influence mental health. To test the role of gonadal hormones in anxiety- and depression-related behavior during puberty, we manipulated gonadal hormones in mice while controlling social and environmental factors. Similar to humans, we find that mice show an increase in depression-related behavior from pre-pubertal to late-pubertal ages, but this increase is not dependent on gonadal hormones and does not differ between sexes. Anxiety-related behavior, however, is more complex during puberty, with differences that depend on sex, age, behavioral test, and hormonal status. Briefly, males castrated before puberty show greater anxiety-related behavior during late puberty compared to intact males, while pubertal females are unaffected by ovariectomy or hormone injections in all assays except the marble burying test. Despite this sex-specific effect of pubertal hormones on anxiety-related behavior, we find no sex differences in intact young adults, suggesting that males and females use separate mechanisms to converge on a similar behavioral phenotype. Our results are consistent with anxiolytic effects of testicular hormones during puberty in males but are not consistent with a causal role for ovarian hormones in increasing anxiety- and depression-related behavior during puberty in females. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gonadal steroids regulate the expression of aggrecanases in human endometrial stromal cells in vitro.

PubMed

Wen, Jiadi; Zhu, Hua; Leung, Peter C K

2013-10-01

The human endometrium undergoes cyclic change during each menstrual cycle in response to gonadal steroids. Proteolysis of endometrial extracellular matrix (ECM) is necessary to prepare this dynamic tissue for pregnancy. Proteolytic enzymes such as matrix metalloproteinase (MMP) and closely related a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been assigned key roles in the highly regulated cyclic remodelling of the endometrial ECM. We have previously shown that ADAMTS-1 undergoes spatiotemporal changes in human endometrial stromal cells under the regulation of gonadal steroids. This suggests that other ADAMTS subtypes, known as aggrecanases, may contribute to the ECM remodelling events that occur in female physiological cycles and in preparation for pregnancy. To determine whether progesterone (P4), 17β-estradiol (E2), or dihydrotestosterone (DHT), alone or in combination, are capable of regulating ADAMTS-4, -5, -8 or -9 expression in human endometrial stromal cells in vitro. Real-time quantitative PCR and Western blot analysis were used to measure ADAMTSs mRNA and protein levels in primary cultures of human endometrial stromal cells (n = 12). P4, DHT but not E2 have regulatory effects on ADAMTS-8, -9 and -5 expression. Combined treatment with gonadal steroids did not show any synergistic or antagonistic effects. However, the synthetic steroid antagonists RU486 and hydroxyflutamide specifically inhibited the P4- or DHT-mediated regulatory effects on ADAMTS expression. These studies provide evidence that the regulation of aggrecanases by gonadal steroids in human endometrial stromal cells may play an important role during decidualization. © 2013 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Molecular cloning and expression of caspase-3 in the protandrous cinnamon clownfish, Amphiprion melanopus, during sex change.

PubMed

Kim, Na Na; Lee, Jehee; Habibi, Hamid R; Choi, Cheol Young

2013-06-01

The caspase-3 appears to be a key protease in the apoptotic pathway. We identified caspase-3 complementary DNAs from the ovaries of the protandrous cinnamon clownfish (Amphiprion melanopus), and investigated its mRNA and proteins, and activity levels during the sex change (I, mature male; II, male at 90 days after removing of the female; and III, mature female). The nucleotide sequence of the caspase-3 cDNA was 969 base pairs in length with open reading frames encoding peptides of 282 amino acids. The caspase-3 mRNA and protein, and activity levels in stages of the mature gonad are higher than those of the development gonad stage. To understand the effect of gonadotropin-releasing hormone (GnRH) on gonad apoptosis, we examined expression of genes caspase-3 mRNA and activity level in immature cinnamon clownfish gonads after GnRH analogue (GnRHa). The findings support the hypothesis that caspase-3 expression is associated with both testicular and ovarian development, and suggests that it may play a role in the control of ovarian development in cinnamon clownfish. Also, we demonstrate that GnRH agonists stimulate caspase-3 production which can in turn stimulate apoptosis. The present study provides a framework for better understanding of the role of caspase-3 during sex change processes in fish.

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. © 2016 Society for Reproduction and Fertility.

Copy Number Variation in Patients with Disorders of Sex Development Due to 46,XY Gonadal Dysgenesis

PubMed Central

White, Stefan; Ohnesorg, Thomas; Notini, Amanda; Roeszler, Kelly; Hewitt, Jacqueline; Daggag, Hinda; Smith, Craig; Turbitt, Erin; Gustin, Sonja; van den Bergen, Jocelyn; Miles, Denise; Western, Patrick; Arboleda, Valerie; Schumacher, Valerie; Gordon, Lavinia; Bell, Katrina; Bengtsson, Henrik; Speed, Terry; Hutson, John; Warne, Garry; Harley, Vincent; Koopman, Peter; Vilain, Eric; Sinclair, Andrew

2011-01-01

Disorders of sex development (DSD), ranging in severity from mild genital abnormalities to complete sex reversal, represent a major concern for patients and their families. DSD are often due to disruption of the genetic programs that regulate gonad development. Although some genes have been identified in these developmental pathways, the causative mutations have not been identified in more than 50% 46,XY DSD cases. We used the Affymetrix Genome-Wide Human SNP Array 6.0 to analyse copy number variation in 23 individuals with unexplained 46,XY DSD due to gonadal dysgenesis (GD). Here we describe three discrete changes in copy number that are the likely cause of the GD. Firstly, we identified a large duplication on the X chromosome that included DAX1 (NR0B1). Secondly, we identified a rearrangement that appears to affect a novel gonad-specific regulatory region in a known testis gene, SOX9. Surprisingly this patient lacked any signs of campomelic dysplasia, suggesting that the deletion affected expression of SOX9 only in the gonad. Functional analysis of potential SRY binding sites within this deleted region identified five putative enhancers, suggesting that sequences additional to the known SRY-binding TES enhancer influence human testis-specific SOX9 expression. Thirdly, we identified a small deletion immediately downstream of GATA4, supporting a role for GATA4 in gonad development in humans. These CNV analyses give new insights into the pathways involved in human gonad development and dysfunction, and suggest that rearrangements of non-coding sequences disturbing gene regulation may account for significant proportion of DSD cases. PMID:21408189

In silico predicted reproductive endocrine transcriptional regulatory networks during zebrafish (Danio rerio) development.

PubMed

Hala, D

2017-03-21

The interconnected topology of transcriptional regulatory networks (TRNs) readily lends to mathematical (or in silico) representation and analysis as a stoichiometric matrix. Such a matrix can be 'solved' using the mathematical method of extreme pathway (ExPa) analysis, which identifies uniquely activated genes subject to transcription factor (TF) availability. In this manuscript, in silico multi-tissue TRN models of brain, liver and gonad were used to study reproductive endocrine developmental programming in zebrafish (Danio rerio) from 0.25h post fertilization (hpf; zygote) to 90 days post fertilization (dpf; adult life stage). First, properties of TRN models were studied by sequentially activating all genes in multi-tissue models. This analysis showed the brain to exhibit lowest proportion of co-regulated genes (19%) relative to liver (23%) and gonad (32%). This was surprising given that the brain comprised 75% and 25% more TFs than liver and gonad respectively. Such 'hierarchy' of co-regulatory capability (brain

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.

Sex Reversal and Comparative Data Undermine the W Chromosome and Support Z-linked DMRT1 as the Regulator of Gonadal Sex Differentiation in Birds.

PubMed

Hirst, Claire E; Major, Andrew T; Ayers, Katie L; Brown, Rosie J; Mariette, Mylene; Sackton, Timothy B; Smith, Craig A

2017-09-01

The exact genetic mechanism regulating avian gonadal sex differentiation has not been completely resolved. The most likely scenario involves a dosage mechanism, whereby the Z-linked DMRT1 gene triggers testis development. However, the possibility still exists that the female-specific W chromosome may harbor an ovarian determining factor. In this study, we provide evidence that the universal gene regulating gonadal sex differentiation in birds is Z-linked DMRT1 and not a W-linked (ovarian) factor. Three candidate W-linked ovarian determinants are HINTW, female-expressed transcript 1 (FET1), and female-associated factor (FAF). To test the association of these genes with ovarian differentiation in the chicken, we examined their expression following experimentally induced female-to-male sex reversal using the aromatase inhibitor fadrozole (FAD). Administration of FAD on day 3 of embryogenesis induced a significant loss of aromatase enzyme activity in female gonads and masculinization. However, expression levels of HINTW, FAF, and FET1 were unaltered after experimental masculinization. Furthermore, comparative analysis showed that FAF and FET1 expression could not be detected in zebra finch gonads. Additionally, an antibody raised against the predicted HINTW protein failed to detect it endogenously. These data do not support a universal role for these genes or for the W sex chromosome in ovarian development in birds. We found that DMRT1 (but not the recently identified Z-linked HEMGN gene) is male upregulated in embryonic zebra finch and emu gonads, as in the chicken. As chicken, zebra finch, and emu exemplify the major evolutionary clades of birds, we propose that Z-linked DMRT1, and not the W sex chromosome, regulates gonadal sex differentiation in birds. Copyright © 2017 Endocrine Society.

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. Copyright © 2014 Elsevier Inc. All rights reserved.

Differential expression analysis of Paralichthys olivaceus microRNAs in adult ovary and testis by deep sequencing.

PubMed

Gu, Yifeng; Zhang, Lei; Chen, Xiaowu

2014-08-01

MicroRNAs (miRNAs) play an important role in gonadal development and differentiation in fish. However, understanding of the mechanism of this process is hindered by our poor knowledge of miRNA expression patterns in fish gonads. In this study, miRNA libraries derived from adult gonads of Paralichthys olivaceus were generated by using next-generation sequencing (NGS) technology. Bioinformatics analysis was performed to distinguish mature miRNA sequences from two classes of small RNAs represented in the sequencing data. A total of 141 mature miRNAs were identified, in which 21 miRNAs were found in P. olivaceus for the first time. Variance and preference of miRNAs expression were concluded from the deep sequencing reads. Some miRNAs, such as pol-miR-143, pol-miR-26a and pol-let-7a were found with quite high expression levels in both gonads, while some exhibited a clear sex-biased expression in different gonad. Approximate 20.0% and 13.1% of the isolated miRNAs were preferentially expressed in the testis (FC<0.5) or ovary (FC>2), respectively. The identification and the preliminary analysis of the sex-biased expression of miRNAs in P. olivaceus gonads in our work by using NGS will provide us a basic catalog of miRNAs to facilitate future improvement and exploitation of sexual regulatory mechanisms in P. olivaceus. Copyright © 2014. Published by Elsevier Inc.

Insulin and IGF1 Receptors Are Essential for XX and XY Gonadal Differentiation and Adrenal Development in Mice

PubMed Central

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. PMID:23300479

Sex determination and maintenance: the role of DMRT1 and FOXL2

PubMed Central

Huang, Shengsong; Ye, Leping; Chen, Haolin

2017-01-01

In many species, including mammals, sex determination is genetically based. The sex chromosomes that individuals carry determine sex identity. Although the genetic base of phenotypic sex is determined at the moment of fertilization, the development of testes or ovaries in the bipotential early gonads takes place during embryogenesis. During development, sex determination depends upon very few critical genes. When one of these key genes functions inappropriately, sex reversal may happen. Consequently, an individual's sex phenotype may not necessarily be consistent with the sex chromosomes that are present. For some time, it has been assumed that once the fetal choice is made between male and female in mammals, the gonadal sex identity of an individual remains stable. However, recent studies in mice have provided evidence that it is possible for the gonadal sex phenotype to be switched even in adulthood. These studies have shown that two key genes, doublesex and mad-3 related transcription factor 1 (Dmrt1) and forkhead box L2 (Foxl2), function in a Yin and Yang relationship to maintain the fates of testes or ovaries in adult mammals, and that mutations in either gene might have a dramatic effect on gonadal phenotype. Thus, adult gonad maintenance in addition to fetal sex determination may both be important for the fertility. PMID:28091399

20 years of leptin: role of leptin in human reproductive disorders.

PubMed

Chou, Sharon H; Mantzoros, Christos

2014-10-01

Leptin, as a key hormone in energy homeostasis, regulates neuroendocrine function, including reproduction. It has a permissive role in the initiation of puberty and maintenance of the hypothalamic-pituitary-gonadal axis. This is notable in patients with either congenital or acquired leptin deficiency from a state of chronic energy insufficiency. Hypothalamic amenorrhea is the best-studied, with clinical trials confirming a causative role of leptin in hypogonadotropic hypogonadism. Implications of leptin deficiency have also emerged in the pathophysiology of hypogonadism in type 1 diabetes. At the other end of the spectrum, hyperleptinemia may play a role in hypogonadism associated with obesity, polycystic ovarian syndrome, and type 2 diabetes. In these conditions of energy excess, mechanisms of reproductive dysfunction include central leptin resistance as well as direct effects at the gonadal level. Thus, reproductive dysfunction due to energy imbalance at both ends can be linked to leptin. © 2014 Society for Endocrinology.

Intermittent Fasting Dietary Restriction Regimen Negatively Influences Reproduction in Young Rats: A Study of Hypothalamo-Hypophysial-Gonadal Axis

PubMed Central

Kumar, Sushil; Kaur, Gurcharan

2013-01-01

Nutritional infertility is very common in societies where women fail to eat enough to match their energy expenditure and such females often present as clinical cases of anorexia nervosa. The cellular and molecular mechanisms that link energy balance and central regulation of reproduction are still not well understood. Peripheral hormones such as estradiol, testosterone and leptin, as well as neuropeptides like kisspeptin and neuropeptides Y (NPY) play a potential role in regulation of reproduction and energy balance with their primary target converging on the hypothalamic median eminence-arcuate region. The present study was aimed to explore the effects of negative energy state resulting from intermittent fasting dietary restriction (IF-DR) regimen on complete hypothalamo-hypophysial-gonadal axis in Wistar strain young female and male rats. Significant changes in body weight, blood glucose, estrous cyclicity and serum estradiol, testosterone and LH level indicated the negative role of IF-DR regimen on reproduction in these young animals. Further, it was elucidated whether serum level of metabolic hormone, leptin plays a mechanistic role in suppressing hypothalamo-hypophysial-gonadal (HPG) axis via energy regulators, kisspeptin and NPY in rats on IF-DR regimen. We also studied the effect of IF-DR regimen on structural remodeling of GnRH axon terminals in median eminence region of hypothalamus along with the glial cell marker, GFAP and neuronal plasticity marker, PSA-NCAM using immunostaining, Western blotting and RT-PCR. Together these data suggest that IF-DR regimen negatively influences reproduction in young animals due to its adverse effects on complete hypothalamus-hypophysial-gonadal axis and may explain underlying mechanism(s) to understand the clinical basis of nutritional infertility. PMID:23382817

Intermittent fasting dietary restriction regimen negatively influences reproduction in young rats: a study of hypothalamo-hypophysial-gonadal axis.

PubMed

Kumar, Sushil; Kaur, Gurcharan

2013-01-01

Nutritional infertility is very common in societies where women fail to eat enough to match their energy expenditure and such females often present as clinical cases of anorexia nervosa. The cellular and molecular mechanisms that link energy balance and central regulation of reproduction are still not well understood. Peripheral hormones such as estradiol, testosterone and leptin, as well as neuropeptides like kisspeptin and neuropeptides Y (NPY) play a potential role in regulation of reproduction and energy balance with their primary target converging on the hypothalamic median eminence-arcuate region. The present study was aimed to explore the effects of negative energy state resulting from intermittent fasting dietary restriction (IF-DR) regimen on complete hypothalamo-hypophysial-gonadal axis in Wistar strain young female and male rats. Significant changes in body weight, blood glucose, estrous cyclicity and serum estradiol, testosterone and LH level indicated the negative role of IF-DR regimen on reproduction in these young animals. Further, it was elucidated whether serum level of metabolic hormone, leptin plays a mechanistic role in suppressing hypothalamo-hypophysial-gonadal (HPG) axis via energy regulators, kisspeptin and NPY in rats on IF-DR regimen. We also studied the effect of IF-DR regimen on structural remodeling of GnRH axon terminals in median eminence region of hypothalamus along with the glial cell marker, GFAP and neuronal plasticity marker, PSA-NCAM using immunostaining, Western blotting and RT-PCR. Together these data suggest that IF-DR regimen negatively influences reproduction in young animals due to its adverse effects on complete hypothalamus-hypophysial-gonadal axis and may explain underlying mechanism(s) to understand the clinical basis of nutritional infertility.

Lactobacillus rhamnosus Accelerates Zebrafish Backbone Calcification and Gonadal Differentiation through Effects on the GnRH and IGF Systems

PubMed Central

Avella, Matteo A.; Place, Allen; Du, Shao-Jun; Williams, Ernest; Silvi, Stefania; Zohar, Yonathan; Carnevali, Oliana

2012-01-01

Endogenous microbiota play essential roles in the host’s immune system, physiology, reproduction and nutrient metabolism. We hypothesized that a continuous administration of an exogenous probiotic might also influence the host’s development. Thus, we treated zebrafish from birth to sexual maturation (2-months treatment) with Lactobacillus rhamnosus, a probiotic species intended for human use. We monitored for the presence of L. rhamnosus during the entire treatment. Zebrafish at 6 days post fertilization (dpf) exhibited elevated gene expression levels for Insulin-like growth factors -I and -II, Peroxisome proliferator activated receptors -α and -β, VDR-α and RAR-γ when compared to untreated-10 days old zebrafish. Using a gonadotropin-releasing hormone 3 GFP transgenic zebrafish (GnRH3-GFP), higher GnRH3 expression was found at 6, 8 and 10 dpf upon L. rhamnosus treatment. The same larvae exhibited earlier backbone calcification and gonad maturation. Noteworthy in the gonad development was the presence of first testes differentiation at 3 weeks post fertilization in the treated zebrafish population -which normally occurs at 8 weeks- and a dramatic sex ratio modulation (93% females, 7% males in control vs. 55% females, 45% males in the treated group). We infer that administration of L. rhamnosus stimulated the IGF system, leading to a faster backbone calcification. Moreover we hypothesize a role for administration of L. rhamnosus on GnRH3 modulation during early larval development, which in turn affects gonadal development and sex differentiation. These findings suggest a significant role of the microbiota composition on the host organism development profile and open new perspectives in the study of probiotics usage and application. PMID:23029107

Avian Polyomavirus Genome Sequences Recovered from Parrots in Captive Breeding Facilities in Poland

PubMed Central

Dayaram, Anisha; Piasecki, Tomasz; Chrząstek, Klaudia; White, Robyn; Julian, Laurel; van Bysterveldt, Katherine

2015-01-01

Eight genomes of avian polyomaviruses (APVs) were recovered and sequenced from deceased Psittacula eupatria, Psittacula krameri, and Melopsittacus undulatus from various breeding facilities in Poland. Of these APV-positive samples, six had previously tested positive for beak and feather disease virus (BFDV) and/or parrot hepatitis B virus (PHBV). PMID:26404592

Caenorhabditis elegans EXO-3 contributes to longevity and reproduction: differential roles in somatic cells and germ cells.

PubMed

Kato, Yuichi; Moriwaki, Takahito; Funakoshi, Masafumi; Zhang-Akiyama, Qiu-Mei

2015-02-01

Apurinic/apyrimidinic (AP) sites are the major DNA damage generated continuously even under normal conditions, and inhibit DNA replication/transcription. AP endonucleases are ubiquitous enzymes required for the repair of AP sites and 3' blocking ends, but their physiological roles in multicellular organisms are not fully understood. In this study, we investigated how an AP endonuclease functions in a multicellular organism (Caenorhabditis elegans (C. elegans)). EXO-3 is one of the AP endonucleases in C. elegans. Using an exo-3 mutant worm, we found that deletion of the exo-3 gene caused shortened lifespan in an ung-1-dependent manner. UNG-1 is a uracil DNA glycosylase in C. elegans, and the present finding suggested that UNG-1 is the major producer of AP sites that affects lifespan, and EXO-3 contributes to longevity by completing the repair of uracil. Next we found that the exo-3 gene was abundantly expressed in the gonads, and AP sites in the gonad were efficiently repaired, suggesting that EXO-3 functioned particularly in the gonad. Deletion of the exo-3 gene resulted in a significant decrease in self-brood size. This was rescued by deficiency of NTH-1, which is a bifunctional DNA glycosylase in C. elegans that recognizes oxidative base damage. This result suggested that the major substrate of EXO-3 in the gonad was 3' blocking end generated by NTH-1, and that EXO-3 played an important role in reproduction. A contribution of EXO-3 to reproduction was also suggested by our finding here that the decrease of self-brood size of the exo-3 mutant became more marked when worms were treated with methyl methanesulfonate (MMS) and sodium bisulfite (NaHSO3). This study demonstrated differential roles of EXO-3 in somatic cells and germ cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Neural, not gonadal, origin of brain sex differences in a gynandromorphic finch.

PubMed

Agate, Robert J; Grisham, William; Wade, Juli; Mann, Suzanne; Wingfield, John; Schanen, Carolyn; Palotie, Aarno; Arnold, Arthur P

2003-04-15

In mammals and birds, sex differences in brain function and disease are thought to derive exclusively from sex differences in gonadal hormone secretions. For example, testosterone in male mammals acts during fetal and neonatal life to cause masculine neural development. However, male and female brain cells also differ in genetic sex; thus, sex chromosome genes acting within cells could contribute to sex differences in cell function. We analyzed the sexual phenotype of the brain of a rare gynandromorphic finch in which the right half of the brain was genetically male and the left half genetically female. The neural song circuit on the right had a more masculine phenotype than that on the left. Because both halves of the brain were exposed to a common gonadal hormone environment, the lateral differences indicate that the genetic sex of brain cells contributes to the process of sexual differentiation. Because both sides of the song circuit were more masculine than that of females, diffusible factors such as hormones of gonadal or neural origin also likely played a role in sexual differentiation.

Sexually dimorphic expression of gonadotropin subunits in the pituitary of protogynous honeycomb grouper (Epinephelus merra): evidence that follicle-stimulating hormone (FSH) induces gonadal sex change.

PubMed

Kobayashi, Yasuhisa; Alam, Mohammad Ashraful; Horiguchi, Ryo; Shimizu, Akio; Nakamura, Masaru

2010-06-01

Recent studies have suggested that the hypothalamic-pituitary-gonadal axis is involved in gonadal sex change in sex-changing teleosts. However, its underlying mechanism remains largely unknown. In this study, we focused on the distinct roles of two gonadotropins (GTHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), in the protogynous hermaphrodite teleost, honeycomb grouper (Epinephelus merra). First, we investigated the expression pattern of mRNAs for GTH subunits (cga, fshb, and lhb) in the pituitaries from fish at the different sexual phases. Real-time RT-PCR analyses showed that fhsb mRNA levels in the female pituitary were low. However, fshb transcripts increased dramatically in association with testis development. In contrast, levels of cga and lhb mRNAs did not significantly vary during sex change. In addition, immunohistochemical observations of Fshb- and Lhb-producing cells in the pituitary, through the use of specific antibodies for detections of teleost GTH subunits, were consistent with sexually dimorphic expression of Fshb. In order to identify the role of GTH in gonad of honeycomb grouper, we treated females with bovine FSH (50 or 500 ng/fish) or LH (500 ng/fish) in vivo. After 3 wk, FSH treatments induced female-to-male sex change and up-regulated endogenous androgen levels and fshb transcripts, whereas LH treatment had no effect on sex change. These results suggest that FSH may trigger the female-to-male sex change in honeycomb grouper.

Complete depletion of primordial germ cells in an All-female fish leads to Sex-biased gene expression alteration and sterile All-male occurrence.

PubMed

Liu, Wei; Li, Shi-Zhu; Li, Zhi; Wang, Yang; Li, Xi-Yin; Zhong, Jian-Xiang; Zhang, Xiao-Juan; Zhang, Jun; Zhou, Li; Gui, Jian-Fang

2015-11-18

Gynogenesis is one of unisexual reproduction modes in vertebrates, and produces all-female individuals with identical genetic background. In sexual reproduction vertebrates, the roles of primordial germ cells on sexual dimorphism and gonadal differentiation have been largely studied, and two distinct functional models have been proposed. However, the role of primordial germ cells remains unknown in unisexual animals, and it is also unclear whether the functional models in sexual reproduction animals are common in unisexual animals. To solve these puzzles, we attempt to utilize the gynogenetic superiority of polyploid Carassius gibelio to create a complete germ cell-depleted gonad model by a similar morpholino-mediated knockdown approach used in other examined sexual reproduction fishes. Through the germ cell-depleted gonad model, we have performed comprehensive and comparative transcriptome analysis, and revealed a complete alteration of sex-biased gene expression. Moreover, the expression alteration leads to up-regulation of testis-biased genes and down-regulation of ovary-biased genes, and results in the occurrence of sterile all-males with testis-like gonads and secondary sex characteristics in the germ cell-depleted gynogenetic Carassius gibelio. Our current results have demonstrated that unisexual gynogenetic embryos remain keeping male sex determination information in the genome, and the complete depletion of primordial germ cells in the all-female fish leads to sex-biased gene expression alteration and sterile all-male occurrence.

Increased HDL cholesterol levels in mice with XX versus XY sex chromosomes

PubMed Central

Link, Jenny C.; Chen, Xuqi; Prien, Christopher; Borja, Mark S.; Hammerson, Bradley; Oda, Michael N.; Arnold, Arthur P.; Reue, Karen

2015-01-01

Objective The molecular mechanisms underlying sex differences in dyslipidemia are poorly understood. We aimed to distinguish genetic and hormonal regulators of sex differences in plasma lipid levels. Approach and Results We assessed the role of gonadal hormones and sex chromosome complement on lipid levels using the Four Core Genotypes mouse model (XX females, XX males, XY females, and XY males). In gonadally intact mice fed a chow diet, lipid levels were influenced by both male–female gonadal sex and XX–XY chromosome complement. Gonadectomy of adult mice revealed that the male–female differences are dependent on acute effects of gonadal hormones. In both intact and gonadectomized animals, XX mice had higher HDL cholesterol (HDL-C) levels than XY mice, regardless of male–female sex. Feeding a cholesterol-enriched diet produced distinct patterns of sex differences in lipid levels compared to a chow diet, revealing the interaction of gonadal and chromosomal sex with diet. Notably, under all dietary and gonadal conditions, HDL-C levels were higher in mice with two X chromosomes compared to mice with an X and Y chromosome. By generating mice with XX, XY and XXY chromosome complements, we determined that the presence of two X chromosomes, and not the absence of the Y chromosome, influences HDL-C concentration. Conclusions We demonstrate that having two X chromosomes versus an X and Y chromosome complement drives sex differences in HDL-C. It is conceivable that increased expression of genes escaping X-inactivation in XX mice regulates downstream processes to establish sexual dimorphism in plasma lipid levels. PMID:26112012

Increased high-density lipoprotein cholesterol levels in mice with XX versus XY sex chromosomes.

PubMed

Link, Jenny C; Chen, Xuqi; Prien, Christopher; Borja, Mark S; Hammerson, Bradley; Oda, Michael N; Arnold, Arthur P; Reue, Karen

2015-08-01

The molecular mechanisms underlying sex differences in dyslipidemia are poorly understood. We aimed to distinguish genetic and hormonal regulators of sex differences in plasma lipid levels. We assessed the role of gonadal hormones and sex chromosome complement on lipid levels using the four core genotypes mouse model (XX females, XX males, XY females, and XY males). In gonadally intact mice fed a chow diet, lipid levels were influenced by both male-female gonadal sex and XX-XY chromosome complement. Gonadectomy of adult mice revealed that the male-female differences are dependent on acute effects of gonadal hormones. In both intact and gonadectomized animals, XX mice had higher HDL cholesterol (HDL-C) levels than XY mice, regardless of male-female sex. Feeding a cholesterol-enriched diet produced distinct patterns of sex differences in lipid levels compared with a chow diet, revealing the interaction of gonadal and chromosomal sex with diet. Notably, under all dietary and gonadal conditions, HDL-C levels were higher in mice with 2 X chromosomes compared with mice with an X and Y chromosome. By generating mice with XX, XY, and XXY chromosome complements, we determined that the presence of 2 X chromosomes, and not the absence of the Y chromosome, influences HDL-C concentration. We demonstrate that having 2 X chromosomes versus an X and Y chromosome complement drives sex differences in HDL-C. It is conceivable that increased expression of genes escaping X-inactivation in XX mice regulates downstream processes to establish sexual dimorphism in plasma lipid levels. © 2015 American Heart Association, Inc.

The expression of amh and amhr2 is associated with the development of gonadal tissue and sex change in the protandrous black porgy, Acanthopagrus schlegeli.

PubMed

Wu, Guan-Chung; Chiu, Po-Chia; Lyu, Ying-Syuan; Chang, Ching-Fong

2010-09-01

The protandrous black porgy, Acanthopagrus schlegeli, has a striking life cycle, with sex differentiation at the juvenile stage, mono-male development, a bisexual gonad during the first 2 yr of life, and a male-to-female sex change (with vitellogenic oocytes) at 3 yr of age. In the present study, we investigated the possible roles of amh and amhr2 in gonadal development in a nonmammalian model organism (protandrous black porgy), especially in relation to sex differentiation, testicular and ovarian growth, and sex change. Fish of various ages were treated with estradiol or an aromatase inhibitor to induce the fish to become female. Furthermore, a natural sex change (2(+)-yr-old [>2 yr and <3 yr] fish) and a nonchemical method to surgically remove one of the pair of gonads to examine the possible roles of amh in the natural sex change were conducted. We present integrative in situ hybridization, immunohistochemical, cellular, and molecular data describing these phenomena. During gonadal sex differentiation, an increase in amh and amhr2 expression was detected. Higher levels of amh and amhr2 transcripts were observed in the testicular tissue when compared to the ovarian tissue in the bisexual gonad of 1(+)-yr-old (>1 yr and <2 yr) fish. Transcripts of amh reached peak levels in November (prespermatogenesis period) and then declined to the lowest levels in January (spawning period). Chemical-induced ovarian tissue had very low amh transcript levels but high levels of amhr2. Active testes had significantly higher amh and amhr2 expression levels as compared to inactive testes. In contrast, no difference in the expression of amh and amhr2 between active and inactive ovarian tissues was found. Transcripts of amh were expressed in the somatic cells of the spermatogonia and vitellogenic oocytes, and amhr2 was expressed in the somatic cells of the spermatogonia. Transcripts of amh decreased in the testicular tissue 5 mo before occurrence of the sex change into a female. In contrast, testicular amh expression remained high if the fish remained male. Human chorionic gonadotropin regulated amh and amhr2 expression in the testicular tissue but not in the ovarian tissue. The present results suggest that amh plays important roles in early testicular and ovarian development, late ovarian growth (e.g., vitellogenic oocytes), and natural sex change in the protandrous black porgy.

Gonad Transcriptome Analysis of the Pacific Oyster Crassostrea gigas Identifies Potential Genes Regulating the Sex Determination and Differentiation Process.

PubMed

Yue, Chenyang; Li, Qi; Yu, Hong

2018-04-01

The Pacific oyster Crassostrea gigas is a commercially important bivalve in aquaculture worldwide. C. gigas has a fascinating sexual reproduction system consisting of dioecism, sex change, and occasional hermaphroditism, while knowledge of the molecular mechanisms of sex determination and differentiation is still limited. In this study, the transcriptomes of male and female gonads at different gametogenesis stages were characterized by RNA-seq. Hierarchical clustering based on genes differentially expressed revealed that 1269 genes were expressed specifically in female gonads and 817 genes were expressed increasingly over the course of spermatogenesis. Besides, we identified two and one gene modules related to female and male gonad development, respectively, using weighted gene correlation network analysis (WGCNA). Interestingly, GO and KEGG enrichment analysis showed that neurotransmitter-related terms were significantly enriched in genes related to ovary development, suggesting that the neurotransmitters were likely to regulate female sex differentiation. In addition, two hub genes related to testis development, lncRNA LOC105321313 and Cg-Sh3kbp1, and one hub gene related to ovary development, Cg-Malrd1-like, were firstly investigated. This study points out the role of neurotransmitter and non-coding RNA regulation during gonad development and produces lists of novel relevant candidate genes for further studies. All of these provided valuable information to understand the molecular mechanisms of C. gigas sex determination and differentiation.

Avian Polyomavirus Genome Sequences Recovered from Parrots in Captive Breeding Facilities in Poland.

PubMed

Dayaram, Anisha; Piasecki, Tomasz; Chrząstek, Klaudia; White, Robyn; Julian, Laurel; van Bysterveldt, Katherine; Varsani, Arvind

2015-09-24

Eight genomes of avian polyomaviruses (APVs) were recovered and sequenced from deceased Psittacula eupatria, Psittacula krameri, and Melopsittacus undulatus from various breeding facilities in Poland. Of these APV-positive samples, six had previously tested positive for beak and feather disease virus (BFDV) and/or parrot hepatitis B virus (PHBV). Copyright © 2015 Dayaram et al.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

The role of estrogen in turtle sex determination and the effect of PCBs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crews, D.; Bergeron, J.M.; McLachlan, J.A.

1995-10-01

Gonadal sex is fixed at fertilization by specific chromosomes, a process known as genotypic sex determination (GSD). Only after the gonad is formed do hormones begin to exert an influence that modifies specific structures that eventually will differ between the sexes. Many egg-laying reptiles do not exhibit GSD but rather depend on the temperature of the incubating egg to determine the gonadal sex of the offspring, a process termed temperature-dependent sex determination (TSD). Research on TSD indicates that gonadal sex is not irrevocably set by the genetic composition inherited at fertilization but depends ultimately on which genes encoding for steroidogenicmore » enzymes and hormone receptors are activated during the midtrimester of embryonic development by temperature. Incubation temperature modifies the activity as well as the temporal and spatial sequence of enzymes and hormone receptors to determine gonad type. Estrogen is the physiologic equivalent of incubation temperature and the proximate cue that initiates female sex determination. increasing evidence indicates some polychlorinated biphenyl (PCB) compounds are capable of disrupting reproductive and endocrine function in fish, birds, and mammals, including humans. Reproductive disorders resulting from exposure to these xenobiotic compounds may include reductions in fertility, hatch rate in fish and birds, and viability of offspring, as well as alterations in hormone levels or adult sexual behaviors. Research on the mechanism through which these compounds may be acting to alter reproductive function indicates estrogenic activity, by which the compounds may be altering sexual differentiation. In TSD turtles, the estrogenic effect of some PCBs reverses gonadal sex in individuals incubating at an otherwise male-producing temperature. Furthermore, certain PCBs are synergistic in their effect at very low concentrations. 19 refs., 3 figs., 1 tab.« less

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. (c) 2007 Wiley-Liss, Inc.

THE DEVELOPMENT OF SEXUAL DIMORPHISM: STUDIES OF THE C. ELEGANS MALE

PubMed Central

Emmons, Scott W.

2014-01-01

Studies of the development of the C. elegans male have been carried out with the aim of understanding the basis of sexual dimorphism. Postembryonic development of the two C. elegans sexes differs extensively. Development along either the hermaphrodite or male pathway is specified initially by the X to autosome ratio. The regulatory events initiated by this ratio include a male-determining paracrine intercellular signal. Expression of this signal leads to different consequences in three regions of the body: the non-gonadal soma, the somatic parts of the gonad, and the germ line. In the non-gonadal soma, activity of the key Zn-finger transcription factor TRA 1 determines hermaphrodite development; in its absence, the male pathway is followed. Only a few genes directly regulated by TRA 1 are currently known, including members of the evolutionarily conserved, male-determining DM domain Zn-finger transcription factors. In the somatic parts of the gonad and germ line, absence of TRA 1 activity is not sufficient for full expression of the male pathway. Several additional transcription factors involved have been identified. In the germ line, regulatory genes for sperm development that act at the level of RNA in the cytoplasm play a prominent role. PMID:25262817

Painful ovulation in a 46,XX SRY −ve adult male with SOX9 duplication

PubMed Central

Kean, Anne-Maree; Ewans, Lisa; Ohnesorg, Thomas; Ayers, Katie L; Watson, Geoff; Vasilaras, Arthur; Sinclair, Andrew H; Twigg, Stephen M; Handelsman, David J

2017-01-01

46,XX disorders of sexual development (DSDs) occur rarely and result from disruptions of the genetic pathways underlying gonadal development and differentiation. We present a case of a young phenotypic male with 46,XX SRY-negative ovotesticular DSD resulting from a duplication upstream of SOX9 presenting with a painful testicular mass resulting from ovulation into an ovotestis. We present a literature review of ovulation in phenotypic men and discuss the role of SRY and SOX9 in testicular development, including the role of SOX9 upstream enhancer region duplication in female-to-male sex reversal. Learning points: In mammals, the early gonad is bipotent and can differentiate into either a testis or an ovary. SRY is the master switch in testis determination, responsible for differentiation of the bipotent gonad into testis. SRY activates SOX9 gene, SOX9 as a transcription factor is the second major gene involved in male sex determination. SOX9 drives the proliferation of Sertoli cells and activates AMH/MIS repressing the ovary. SOX9 is sufficient to induce testis formation and can substitute for SRY function. Assessing karyotype and then determination of the presence or absence of Mullerian structures are necessary serial investigations in any case of DSD, except for mixed gonadal dysgenesis identified by karyotype alone. Treatment is ideal in a multidisciplinary setting with considerations to genetic (implications to family and reproductive recurrence risk), psychological aspects (sensitive individualized counseling including patient gender identity and preference), endocrinological (hormone replacement), surgical (cosmetic, prophylactic gonadectomy) fertility preservation and reproductive opportunities and metabolic health (cardiovascular and bones). PMID:28620497

Painful ovulation in a 46,XX SRY -ve adult male with SOX9 duplication.

PubMed

Shankara Narayana, Nandini; Kean, Anne-Maree; Ewans, Lisa; Ohnesorg, Thomas; Ayers, Katie L; Watson, Geoff; Vasilaras, Arthur; Sinclair, Andrew H; Twigg, Stephen M; Handelsman, David J

2017-01-01

46,XX disorders of sexual development (DSDs) occur rarely and result from disruptions of the genetic pathways underlying gonadal development and differentiation. We present a case of a young phenotypic male with 46,XX SRY-negative ovotesticular DSD resulting from a duplication upstream of SOX9 presenting with a painful testicular mass resulting from ovulation into an ovotestis. We present a literature review of ovulation in phenotypic men and discuss the role of SRY and SOX9 in testicular development, including the role of SOX9 upstream enhancer region duplication in female-to-male sex reversal. In mammals, the early gonad is bipotent and can differentiate into either a testis or an ovary. SRY is the master switch in testis determination, responsible for differentiation of the bipotent gonad into testis.SRY activates SOX9 gene, SOX9 as a transcription factor is the second major gene involved in male sex determination. SOX9 drives the proliferation of Sertoli cells and activates AMH/MIS repressing the ovary. SOX9 is sufficient to induce testis formation and can substitute for SRY function.Assessing karyotype and then determination of the presence or absence of Mullerian structures are necessary serial investigations in any case of DSD, except for mixed gonadal dysgenesis identified by karyotype alone.Treatment is ideal in a multidisciplinary setting with considerations to genetic (implications to family and reproductive recurrence risk), psychological aspects (sensitive individualized counseling including patient gender identity and preference), endocrinological (hormone replacement), surgical (cosmetic, prophylactic gonadectomy) fertility preservation and reproductive opportunities and metabolic health (cardiovascular and bones).

Spatial occurrence of a habitat-tracking saproxylic beetle inhabiting a managed forest landscape.

PubMed

Schroeder, L Martin; Ranius, Thomas; Ekbom, Barbara; Larsson, Stig

2007-04-01

Because of the dynamic nature of many managed habitats, proper evaluation of conservation efforts calls for models that take into account both spatial and temporal habitat dynamics. We develop a metapopulation model for successional-type systems, in which habitat quality changes over time in a predictable fashion. The occupancy and recruitment of the predatory saproxylic (dependent on dead wood) beetle Harminius undulatus was studied in a managed boreal forest landscape, covering 24,449 ha, in central Sweden. In a first step, we analyzed the beetle's occupancy pattern in relation to stand characteristics, and the amounts of present and past habitat in the surrounding landscape. Managed forest is suitable habitat when > or =60 years old, and immediately after cutting, but not between the ages of 10 and 60 years. The observed occupancy of H. undulatus was positively correlated with the stand's age as habitat. We used a metapopulation model to predict the current probability of occurrence in each forest stand, given the spatiotemporal distribution of suitable forest stands during the last 50 years. Metapopulation parameters were estimated by matching predicted spatial distributions with observed spatial distributions. The model predicted observed spatial distributions better than a similar model that assumed constant habitat quality of each forest stand. Thus, metapopulation models for successional-type systems, such as dead wood dependent organisms in managed forest landscapes, should include habitat dynamics. An estimated 82% of the landscape-wide recruitment took place in managed stands, which covered 87% of the forest area, in comparison with 18% in unmanaged stands, which covered 13% of the forest area. Among the managed stand types, > or =60-year-old stands and 3-7-year-old clear-cuttings contributed to 79% of the total recruitment while 8-59-year-old stands only contributed 3%. The results suggest the following guidelines to improve conditions for H. undulatus and other species with similar habitat requirements: (1) the proportion of the landscape constituted by younger stands should not be allowed to grow too large, (2) the rotation period of managed stands should not be allowed to be too short, and (3) dead wood should be retained and created at final cutting.

Anti-Müllerian Hormone Is Required for Chicken Embryonic Urogenital System Growth but Not Sexual Differentiation.

PubMed

Lambeth, Luke S; Ayers, Katie; Cutting, Andrew D; Doran, Timothy J; Sinclair, Andrew H; Smith, Craig A

2015-12-01

In mammals, the primary role of anti-Müllerian hormone (AMH) during development is the regression of Müllerian ducts in males. These structures otherwise develop into fallopian tubes, oviducts, and upper vagina, as in females. This highly conserved function is retained in birds and is supported by the high levels of AMH expression in developing testes. In mammals, AMH expression is controlled partly by the transcription factor, SOX9. However, in the chicken, AMH mRNA expression precedes that of SOX9 , leading to the view that AMH may lie upstream of SOX9 and play a more central role in avian testicular development. To help define the role of AMH in chicken gonad development, we suppressed AMH expression in chicken embryos using RNA interference. In males, AMH knockdown did not affect the expression of key testis pathway genes, and testis cords developed normally. However, a reduction in the size of the mesonephros and gonads was observed, a phenotype that was evident in both sexes. This growth defect occurred as a result of the reduced proliferative capacity of the cells of these tissues, and male gonads also had a significant reduction in germ cell numbers. These data suggest that although AMH does not directly contribute to testicular or ovarian differentiation, it is required in a sex-independent manner for proper cell proliferation and urogenital system growth. © 2015 by the Society for the Study of Reproduction, Inc.

Photorefractoriness in birds--photoperiodic and non-photoperiodic control.

PubMed

Dawson, Alistair; Sharp, Peter J

2007-01-01

Avian breeding seasons vary in length and in the degree of asymmetry with respect to the annual cycle in photoperiod to suit species-specific food resources. Asymmetry is the result of photorefractoriness. The degree of photorefractoriness, absolute or relative, is related to the length and asymmetry of the breeding season. Absolute photorefractoriness is associated with a marked decrease in hypothalamic cGnRH-I. However, during the initiation of absolute photorefractoriness there is a transient period during which the gonads regress in advance of the decrease in cGnRH-I, and this stage may be analogous to relative photorefractoriness. Photoinduced prolactin secretion has an inhibitory modulatory role during the initiation of absolute photorefractoriness, but is unlikely to be the only factor involved, while a possible role for avian gonadotrophin inhibitory hormone is not established. The first stage in the termination of photorefractoriness is the resumption of cGnRH-I synthesis. The major environmental cue driving gonadal maturation, and the transitions between the photosensitive state and photorefractoriness is the annual cycle in photoperiod. A range of non-photoperiodic cues may also play a role: social cues, climatic factors (temperature, rainfall, etc.), food availability and nutritional state. There is considerable evidence that these cues can influence gonadal maturation and the timing of egg-laying. There is some evidence that non-photoperiodic cues (certainly temperature and possibly social cues and food availability) can affect the timing of the onset of photorefractoriness, but no evidence that they can influence the time of the end of photorefractoriness.

Ghrelin: an emerging player in the regulation of reproduction in non-mammalian vertebrates.

PubMed

Unniappan, Suraj

2010-07-01

The endocrine regulation of vertebrate reproduction is achieved by the coordinated actions of multiple endocrine factors mainly produced from the brain, pituitary, and gonads. In addition to these, several other tissues including the fat and gut produce factors that have reproductive effects. Ghrelin is one such gut/brain hormone with species-specific effects in the regulation of mammalian reproduction. Recent studies have shown that ghrelin and ghrelin receptor mRNAs, and protein are expressed in the ovary and testis of mammals, indicating a direct effect for ghrelin in the control of reproduction. Ghrelin regulates mammalian reproduction by modulating hormone secretion from the brain and pituitary, and by acting directly on the gonads to influence reproductive tissue development and steroid hormone release. Based on the studies reported so far, ghrelin seems to have a predominantly inhibitory role on mammalian reproduction. The presence of ghrelin and ghrelin receptor has been found in the brain, pituitary and gonads of several non-mammalian vertebrates. In contrast to mammals, ghrelin seems to have a stimulatory role in the regulation of non-mammalian reproduction. The main objective of this review is to do a perspective analysis of the comparative aspects of ghrelin regulation of reproduction. (c) 2009 Elsevier Inc. All rights reserved.

The Need for Speed: Neuroendocrine Regulation of Socially-controlled Sex Change.

PubMed

Lamm, Melissa S; Liu, Hui; Gemmell, Neil J; Godwin, John R

2015-08-01

Socially-controlled functional sex change in fishes is a dramatic example of adaptive reproductive plasticity. Functional gonadal sex change can occur within a week while behavioral sex change can begin within minutes. Significant progress has been made in understanding the neuroendocrine bases of this phenomenon at both the gonadal and the neurobiological levels, but a detailed mechanistic understanding remains elusive. We are working with sex-changing wrasses to identify evolutionarily-conserved neuroendocrine pathways underlying this reproductive adaptation. One key model is the bluehead wrasse (Thalassoma bifasciatum), in which sex change is well studied at the behavioral, ecological, and neuroendocrine levels. Bluehead wrasses show rapid increases in aggressive and courtship behaviors with sex change that do not depend on the presence of gonads. The display of male-typical behavior is correlated with the expression of arginine vasotocin, and experiments support a role for this neuropeptide. Estrogen synthesis is also critical in the process. Female bluehead wrasses have higher abundance of aromatase mRNA in the brain and gonads, and estrogen implants block behavioral sex change. While established methods have advanced our understanding of sex change, a full understanding will require new approaches and perspectives. First, contributions of other neuroendocrine systems should be better characterized, particularly glucocorticoid and thyroid signaling. Second, advances in genomics for non-traditional model species should allow conserved mechanisms to be identified with a key next-step being manipulative tests of these mechanisms. Finally, advances in genomics now also allow study of the role of epigenetic modifications and other regulatory mechanisms in the dramatic alterations across the sex-change process. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Deletions of 9p and the quest for a conserved mechanism of sex determination.

PubMed

Ottolenghi, C; McElreavey, K

2000-01-01

Distal chromosome 9p contains a locus that, when deleted, is a cause of 46,XY gonadal dysgenesis in the absence of extragenital anomalies. This locus might account for the frequently observed cases of 46,XY pure gonadal dysgenesis who do not harbor mutations in SRY, the sex master regulator gene found in mammalian species. The genomic organization of 9p positional candidate genes is currently being studied and mutational screens are ongoing. Among other positional candidates, including two additional doublesex-related genes, the evidence to support a role for the gene DMRT1 in vertebrate male sexual development is accumulating. Although formal proof of the requirement of DMRT1 in gonadal sex fate choice has not been obtained so far, the particular interest in this gene and perhaps other doublesex-related genes identified in vertebrates lies in that they may provide an entry point to a conserved mechanism of sex determination across animal phyla. We discuss recent results and emerging views on the genetics of sex determination, while stressing that the majority of cases of 46,XY gonadal dysgenesis remain unexplained. The latter is likely to be efficiently addressed by positional cloning efforts, particularly by considering the wealth of sequence data provided by the Human Genome Project. Copyright 2000 Academic Press.

Gonadotrophic cells and gonadal sex differentiation in medaka: Characterization of several northern and southern strains.

PubMed

Horie, Yoshifumi; Kobayashi, Tohru

2015-07-01

Gonadotropins play an important role in gametogenesis and reproduction in vertebrates. Their localization in the pituitary during gonadal sex differentiation has been studied mainly in southern (Oryzias latipes) strains of medaka fish, with that in northern medaka (O. sakaizumii) remaining poorly understood. Hence, in this study, we characterized gonadal differentiation and gonadotrophic cells during sex differentiation in two northern strains (HNI and Kaga) and two southern strains (Hd-rR and d-rR/Tokyo). All strains exhibited similar sex differentiation at hatching, such as (1) sex difference in germ cell number (XX > XY), and (2) the transition of XX germ cells into meiosis, and (3) presence of glycoprotein-α (Gpa)-positive cells. However, follicle-stimulating hormone-β (Fshb)-positive cells were first detected in the pituitary 1 day post-hatching in HNI. Exposure to high-temperature conditions and to cortisol in a dose dependent manner resulted in the localization of Fshb cells in the pituitary at hatching. This study demonstrates differences in gonadotropin subunit expression between northern and southern strains of medaka, and suggests that Fsh is not involved in early gonadal sex differentiation, such as the sex difference in germ cell number, and that high-temperature induce Fshb expression via cortisol production in medaka. © 2015 Wiley Periodicals, Inc.

Functional insights into the testis transcriptome of the edible sea urchin Loxechinus albus

PubMed Central

Gaitán-Espitia, Juan Diego; Sánchez, Roland; Bruning, Paulina; Cárdenas, Leyla

2016-01-01

The edible sea urchin Loxechinus albus (Molina, 1782) is a keystone species in the littoral benthic systems of the Pacific coast of South America. The international demand for high-quality gonads of this echinoderm has led to an extensive exploitation and decline of its natural populations. Consequently, a more thorough understanding of L. albus gonad development and gametogenesis could provide valuable resources for aquaculture applications, management, conservation and studies about the evolution of functional and structural pathways that underlie the reproductive toolkit of marine invertebrates. Using a high-throughput sequencing technology, we explored the male gonad transcriptome of this highly fecund sea urchin. Through a de novo assembly approach we obtained 42,530 transcripts of which 15,544 (36.6%) had significant alignments to known proteins in public databases. From these transcripts, approximately 73% were functionally annotated allowing the identification of several candidate genes that are likely to play a central role in developmental processes, nutrient reservoir activity, sexual reproduction, gamete generation, meiosis, sex differentiation, sperm motility, male courtship behavior and fertilization. Additionally, comparisons with the male gonad transcriptomes of other echinoderms revealed several conserved orthologous genes, suggesting that similar functional and structural pathways underlie the reproductive development in this group and other marine invertebrates. PMID:27805042

Development without germ cells: the role of the germ line in zebrafish sex differentiation.

PubMed

Slanchev, Krasimir; Stebler, Jürg; de la Cueva-Méndez, Guillermo; Raz, Erez

2005-03-15

The progenitors of the gametes, the primordial germ cells (PGCs) are typically specified early in the development in positions, which are distinct from the gonad. These cells then migrate toward the gonad where they differentiate into sperms and eggs. Here, we study the role of the germ cells in somatic development and particularly the role of the germ line in the sex differentiation in zebrafish. To this end, we ablated the germ cells using two independent methods and followed the development of the experimental fish. First, PGCs were ablated by knocking down the function of dead end, a gene important for the survival of this lineage. Second, a method to eliminate the PGCs using the toxin-antitoxin components of the parD bacterial genetic system was used. Specifically, we expressed a bacterial toxin Kid preferentially in the PGCs and at the same time protected somatic cells by uniformly expressing the specific antidote Kis. Our results demonstrate an unexpected role for the germ line in promoting female development because PGC-ablated fish invariably developed as males.

Development without germ cells: The role of the germ line in zebrafish sex differentiation

PubMed Central

Slanchev, Krasimir; Stebler, Jürg; de la Cueva-Méndez, Guillermo; Raz, Erez

2005-01-01

The progenitors of the gametes, the primordial germ cells (PGCs) are typically specified early in the development in positions, which are distinct from the gonad. These cells then migrate toward the gonad where they differentiate into sperms and eggs. Here, we study the role of the germ cells in somatic development and particularly the role of the germ line in the sex differentiation in zebrafish. To this end, we ablated the germ cells using two independent methods and followed the development of the experimental fish. First, PGCs were ablated by knocking down the function of dead end, a gene important for the survival of this lineage. Second, a method to eliminate the PGCs using the toxin–antitoxin components of the parD bacterial genetic system was used. Specifically, we expressed a bacterial toxin Kid preferentially in the PGCs and at the same time protected somatic cells by uniformly expressing the specific antidote Kis. Our results demonstrate an unexpected role for the germ line in promoting female development because PGC-ablated fish invariably developed as males. PMID:15728735

Sex differentiation and sex change in the protandrous black porgy, Acanthopagrus schlegeli.

PubMed

Wu, Guan-Chung; Tomy, Sherly; Lee, Mong-Fong; Lee, Yan-Horn; Yueh, Wen-Shiun; Lin, Chien-Ju; Lau, En-Lieng; Chang, Ching-Fong

2010-07-01

Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle with a male sex differentiation at the juvenile stage and male-to-female sex change at 3 years of age. We had characterized the sex differentiation and sex change in this species by the integrative approaches of histology, endocrine and molecular genetics. The fish differentiated in gonad at the age around 4-months and the gonad further developed with a bisexual gonad for almost for 3 years and sex change at 3 year of age. An antagonistic relationship in the testicular and ovarian tissues was found during the development of the gonadal tissue. Male- (such as sf-1, dmrt1, dax-1 and amh) and female- (such as wnt4, foxl2 and cyp19a1a) promoting genes were associated with testicular and ovarian development, respectively. During gonadal sex differentiation, steroidogenic pathway and estrogen signaling were also highly expressed in the brain. The increased expression of sf-1 and wnt4, cyp19a1a in ovarian tissue and decreased expression of dax-1 in the ovarian tissue may play important roles in sex change from a male-to-female. Endocrine factors such as estradiol and luteinizing hormone may also involve in the natural sex change. Estradiol induced the expression of female-promoting genes and resulted in the precocious sex change in black porgy. Our series of studies shed light on the sex differentiation and sex change in protandrous black porgy and other animals. (c) 2009 Elsevier Inc. All rights reserved.

Reproductive biology of blood cockle Anadara granosa (Bivalvia: Arcidae) in the northern region of the Strait of Malacca

NASA Astrophysics Data System (ADS)

Khalil, Munawar; Yasin, Zulfigar; Hwai, Tan Shau

2017-03-01

A study on the reproductive cycle of the blood cockle Anadara granosa (Bivalvia: Arcidae) was conducted at three different areas in the northern region of the Strait of Malacca. A total of 1,920 samples of adult A. granosa (38-71 mm length) were collected from June 2009 until September 2010. Qualitative techniques (gonadal microscopic fresh smear test and histology analysis) as well as quantitative techniques (analysis of condition index and gonadal index) were used to predict monthly gonadal development stages of A. granosa. The gonadal index of A. granosa from Banda Aceh (Indonesia) ( r = 0.469, P > 0.05) and Pulau Pinang (Malaysia) ( r = 0.123, P > 0.05) did not show any correlation to their condition index, whereas the gonadal index of A. granosa from Lhokseumawe (Indonesia) ( r = 0.609, P < 0.05) showed moderate positive correlation to the condition index. During the 16 month sampling period, four reproductive cycles were observed: each from three to six months. The process of releasing gametes is termed dribble spawning, and is the same in all populations. The principle component analysis (PCA) indicated that A. granosa reproduction was affected by interaction between internal physiological factors and indigenous environmental factors. In all sampling areas, phytoplankton density played a key role in the reproductive cycle in A. granosa. Information on the reproductive biology of this species is essential for species management and to improve the sustainability practices of the fisheries industry. These findings will provide basic information on the biology of the blood cockle A. granosa for stock management in the region.

Ultimobranchial gland respond in a different way in male and female fresh water teleost Mastacembelus armatus (Lacepede) during reproductive cycle.

PubMed

Verma, Sushant Kumar; Alim, Abdul

2015-05-01

The present study was carried out to analyze the differences in the activity of ultimobranchial gland (UBG) between male and female fresh water teleost Mastacembelus armatus during reproductive cycle. Considerable variations in the nuclear diameter of UBG cells and plasma calcitonin (CT) levels during different reproductive phases of testicular and ovarian cycle suggested that the activity of the UBG depends upon the sexual maturity of fishes. A positive correlation was observed between plasma CT and sex steroid levels and the gonadosomatic index in both sexes which further confirmed the involvement of UBG in the processes related to gonadal development in fishes irrespective of the sex. Sudden increase in the level of plasma CT and nuclear diameter of UBG cells after administration of 17 α-methyltestosterone in males and 17 β-estradiol in females during resting phase of the reproductive cycle clearly showed that UBG becomes hyperactive with increases in the level of sex steroids. Plasma calcium level was also found to be positively correlated with gonadal maturation in females. However no such change in plasma calcium level in relation to testicular cycle was observed. Thus it can be concluded that UBG becomes hyperactive during gonadal maturation but its role differs between male and female fishes. In females it may involved in both gonadal maturation and plasma calcium regulation while in males its involvement in calcium regulation was not justified. Variations in the level of CT during various phases of testicular cycle evidenced its involvement in gonadal maturation only. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of immune stress on body weight regulation is altered by ovariectomy in female rats.

PubMed

Iwasa, Takeshi; Matsuzaki, Toshiya; Kinouchi, Riyo; Gereltsetseg, Ganbat; Murakami, Masahiro; Nakazawa, Hiroshi; Fujisawa, Shinobu; Yamamoto, Satoshi; Kuwahara, Akira; Yasui, Toshiyuki; Irahara, Minoru

2011-09-01

It has been suggested that obesity and loss of ovarian function alter the inflammatory response to immune stress. Ovariectomized (OVX) rats, which are used as a model of human menopause, exhibit both hyperphagia-induced obesity and gonadal steroid deficiency. To evaluate the effects of ovariectomy on inflammatory responses, we compared the anorectic response to LPS in OVX rats and gonad intact female rats. As leptin and hypothalamic interleukin-1β (IL1β) play pivotal roles in the anorectic response to immune stress, these factors were also measured. It was found that the OVX rats exhibited an increased anorectic response to LPS compared with the sham-operated rats. The OVX rats showed higher serum leptin concentrations and a greater increase in hypothalamic IL1β mRNA expression after LPS injection. In addition, in order to determine whether gonadal steroid deficiency contributes to the changes in the inflammatory responses of OVX rats, we compared responses between OVX rats treated with gonadal steroids and untreated OVX rats. There were no differences in appetite, the serum leptin level, and hypothalamic IL1β mRNA expression between the two groups after LPS injection. These findings suggest that the loss of ovarian function increases the induction of leptin and hypothalamic IL1β synthesis and consequently increases the anorectic response under immune stress conditions. It is possible that these alterations are caused by OVX-induced obesity rather than the direct effects of gonadal steroid deficiency. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A genome-wide survey of sexually dimorphic expression of Drosophila miRNAs identifies the steroid hormone-induced miRNA let-7 as a regulator of sexual identity.

PubMed

Fagegaltier, Delphine; König, Annekatrin; Gordon, Assaf; Lai, Eric C; Gingeras, Thomas R; Hannon, Gregory J; Shcherbata, Halyna R

2014-10-01

MiRNAs bear an increasing number of functions throughout development and in the aging adult. Here we address their role in establishing sexually dimorphic traits and sexual identity in male and female Drosophila. Our survey of miRNA populations in each sex identifies sets of miRNAs differentially expressed in male and female tissues across various stages of development. The pervasive sex-biased expression of miRNAs generally increases with the complexity and sexual dimorphism of tissues, gonads revealing the most striking biases. We find that the male-specific regulation of the X chromosome is relevant to miRNA expression on two levels. First, in the male gonad, testis-biased miRNAs tend to reside on the X chromosome. Second, in the soma, X-linked miRNAs do not systematically rely on dosage compensation. We set out to address the importance of a sex-biased expression of miRNAs in establishing sexually dimorphic traits. Our study of the conserved let-7-C miRNA cluster controlled by the sex-biased hormone ecdysone places let-7 as a primary modulator of the sex-determination hierarchy. Flies with modified let-7 levels present doublesex-related phenotypes and express sex-determination genes normally restricted to the opposite sex. In testes and ovaries, alterations of the ecdysone-induced let-7 result in aberrant gonadal somatic cell behavior and non-cell-autonomous defects in early germline differentiation. Gonadal defects as well as aberrant expression of sex-determination genes persist in aging adults under hormonal control. Together, our findings place ecdysone and let-7 as modulators of a somatic systemic signal that helps establish and sustain sexual identity in males and females and differentiation in gonads. This work establishes the foundation for a role of miRNAs in sexual dimorphism and demonstrates that similar to vertebrate hormonal control of cellular sexual identity exists in Drosophila. Copyright © 2014 by the Genetics Society of America.

Cloning and expression of R-Spondin1 in different vertebrates suggests a conserved role in ovarian development.

PubMed

Smith, Craig A; Shoemaker, Christina M; Roeszler, Kelly N; Queen, Joanna; Crews, David; Sinclair, Andrew H

2008-07-24

R-Spondin1 (Rspo1) is a novel regulator of the Wnt/beta-catenin signalling pathway. Loss-of-function mutations in human RSPO1 cause testicular differentiation in 46, XX females, pointing to a role in ovarian development. Here we report the cloning and comparative expression analysis of R-SPONDIN1 orthologues in the mouse, chicken and red-eared slider turtle, three species with different sex-determining mechanisms. Evidence is presented that this gene is an ancient component of the vertebrate ovary-determining pathway. Gonadal RSPO1 gene expression is female up-regulated in the embryonic gonads in each species at the onset of sexual differentiation. In the mouse gonad, Rspo1 mRNA is expressed in the somatic cell lineage at the time of ovarian differentiation (E12.5-E15.5), with little expression in germ cells. However, the protein is localised in the cytoplasm and at the cell surface of both somatic (pre-follicular) and germ cells. In the chicken embryo, RSPO1 expression becomes elevated in females at the time of ovarian differentiation, coinciding with female-specific activation of the FOXL2 gene and estrogen synthesis. RSPO1 protein in chicken is localised in the outer cortical zone of the developing ovary, the site of primordial follicle formation and germ cell differentiation. Inhibition of estrogen synthesis with a specific aromatase inhibitor results in a decline in chicken RSPO1 expression, indicating that RSPO1 is influenced by estrogen. In the red-eared slider turtle, which exhibits temperature-dependent sex determination, up-regulation of RSPO1 occurs during the temperature-sensitive period, when gonadal development is responsive to temperature. Accordingly, RSPO1 expression is temperature-responsive, and is down-regulated in embryos shifted from female- to male-producing incubation temperatures. These results indicate that RSPO1 is up-regulated in the embryonic gonads of female vertebrates with different sex-determining mechanisms. In all instances, RSPO1 is expressed in the incipient ovary. These findings suggest that R-SPONDIN1 is an ancient, conserved part of the vertebrate ovary-determining pathway.

Cloning and expression of R-Spondin1 in different vertebrates suggests a conserved role in ovarian development

PubMed Central

Smith, Craig A; Shoemaker, Christina M; Roeszler, Kelly N; Queen, Joanna; Crews, David; Sinclair, Andrew H

2008-01-01

Background R-Spondin1 (Rspo1) is a novel regulator of the Wnt/β-catenin signalling pathway. Loss-of-function mutations in human RSPO1 cause testicular differentiation in 46, XX females, pointing to a role in ovarian development. Here we report the cloning and comparative expression analysis of R-SPONDIN1 orthologues in the mouse, chicken and red-eared slider turtle, three species with different sex-determining mechanisms. Evidence is presented that this gene is an ancient component of the vertebrate ovary-determining pathway. Results Gonadal RSPO1 gene expression is female up-regulated in the embryonic gonads in each species at the onset of sexual differentiation. In the mouse gonad, Rspo1 mRNA is expressed in the somatic cell lineage at the time of ovarian differentiation (E12.5–E15.5), with little expression in germ cells. However, the protein is localised in the cytoplasm and at the cell surface of both somatic (pre-follicular) and germ cells. In the chicken embryo, RSPO1 expression becomes elevated in females at the time of ovarian differentiation, coinciding with female-specific activation of the FOXL2 gene and estrogen synthesis. RSPO1 protein in chicken is localised in the outer cortical zone of the developing ovary, the site of primordial follicle formation and germ cell differentiation. Inhibition of estrogen synthesis with a specific aromatase inhibitor results in a decline in chicken RSPO1 expression, indicating that RSPO1 is influenced by estrogen. In the red-eared slider turtle, which exhibits temperature-dependent sex determination, up-regulation of RSPO1 occurs during the temperature-sensitive period, when gonadal development is responsive to temperature. Accordingly, RSPO1 expression is temperature-responsive, and is down-regulated in embryos shifted from female- to male-producing incubation temperatures. Conclusion These results indicate that RSPO1 is up-regulated in the embryonic gonads of female vertebrates with different sex-determining mechanisms. In all instances, RSPO1 is expressed in the incipient ovary. These findings suggest that R-SPONDIN1 is an ancient, conserved part of the vertebrate ovary-determining pathway. PMID:18651984

TAC3 and TACR3 mutations in familial hypogonadotropic hypogonadism reveal a key role for Neurokinin B in the central control of reproduction.

PubMed

Topaloglu, A Kemal; Reimann, Frank; Guclu, Metin; Yalin, Ayse Serap; Kotan, L Damla; Porter, Keith M; Serin, Ayse; Mungan, Neslihan O; Cook, Joshua R; Imamoglu, Sazi; Akalin, N Sema; Yuksel, Bilgin; O'Rahilly, Stephen; Semple, Robert K

2009-03-01

The timely secretion of gonadal sex steroids is essential for the initiation of puberty, the postpubertal maintenance of secondary sexual characteristics and the normal perinatal development of male external genitalia. Normal gonadal steroid production requires the actions of the pituitary-derived gonadotropins, luteinizing hormone and follicle-stimulating hormone. We report four human pedigrees with severe congenital gonadotropin deficiency and pubertal failure in which all affected individuals are homozygous for loss-of-function mutations in TAC3 (encoding Neurokinin B) or its receptor TACR3 (encoding NK3R). Neurokinin B, a member of the substance P-related tachykinin family, is known to be highly expressed in hypothalamic neurons that also express kisspeptin, a recently identified regulator of gonadotropin-releasing hormone secretion. These findings implicate Neurokinin B as a critical central regulator of human gonadal function and suggest new approaches to the pharmacological control of human reproduction and sex hormone-related diseases.

A Case of Two Sisters Suffering from 46,XY Gonadal Dysgenesis and Carrying a Mutation of a Novel Candidate Sex-Determining Gene STARD8 on the X Chromosome.

PubMed

Ilaslan, Erkut; Calvel, Pierre; Nowak, Dominika; Szarras-Czapnik, Maria; Slowikowska-Hilczer, Jolanta; Spik, Anna; Sararols, Pauline; Nef, Serge; Jaruzelska, Jadwiga; Kusz-Zamelczyk, Kamila

2018-06-08

Identification of novel genes involved in sexual development is crucial for understanding disorders of sex development (DSD). Here, we propose a member of the START domain family, the X chromosome STARD8, as a DSD candidate gene. We have identified a missense mutation of this gene in 2 sisters with 46,XY gonadal dysgenesis, inherited from their heterozygous mother. Gonadal tissue of one of the sisters contained Leydig cells overloaded with cholesterol droplets, i.e., structures previously identified in 46,XY DSD patients carrying mutations in the STAR gene encoding another START domain family member, which is crucial for steroidogenesis. Based on the phenotypes of our patients, we propose a dual role of STARD8 in sexual development, namely in testes determination and testosterone synthesis. However, further studies are needed to confirm the involvement of STARD8 in sexual development. © 2018 S. Karger AG, Basel.

Elemental composition of two ecologically contrasting seamount fishes, the bluemouth (Helicolenus dactylopterus) and blackspot seabream (Pagellus bogaraveo).

PubMed

Raimundo, Joana; Vale, Carlos; Martins, Inês; Fontes, Jorge; Graça, Gonçalo; Caetano, Miguel

2015-11-15

Concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb were determined in muscle, liver and gonads of two ecologically contrasting fishes, Helicolenus dactylopterus (benthic) and Pagellus bogaraveo (benthopelagic). Elevated concentrations of As, Se and Cd found in tissues of both species appear to mirror the contribution of volcanic activity to the natural inputs of elements to Azorean waters. Results showed different element accumulation between the two species. Whereas higher concentrations were found in the liver of P. bogaraveo, elevated values were observed in the muscle of H. dactylopterus. Differences in accumulation are most likely related to metabolic rates, diet specificities and habitat. Concentrations in gonads varied up to four orders of magnitude, being higher and more variable in P. bogaraveo than H. dactylopterus. Elevated values of Cd were detected in gonads of both species despite its non-essential role on metabolic functions, presumably related to elimination. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sex- and tissue-specific expression of P450 aromatase (cyp19a1a) in the yellowtail clownfish, Amphiprion clarkii.

PubMed

Kobayashi, Yasuhisa; Horiguchi, Ryo; Miura, Saori; Nakamura, Masaru

2010-02-01

To investigate the role of estrogen in the gonad of yellowtail clownfish Amphiprion clarkii, we isolated cDNA encoding cytochrome P450 aromatase (Cyp19a1a) from the adult ovary. The full-length cDNA of clownfish cyp19a1a is 1928-bp long and encodes 520 amino acids. Real-time quantitative RT-PCR analysis showed that cyp19a1a was expressed mainly in the ovary of female-phase fish. In situ hybridization and immunohistochemical observations showed that positive signals were restricted to the ovarian follicle of the female-phase fish. In contrast, Cyp19a1a signal was not detected in the ambisexual gonad of the male-phase fish. These findings suggest that Cyp19a1a is involved in oogenesis in the female-phase fish, but not in the ambisexual gonad of male-phase fish. 2009 Elsevier Inc. All rights reserved.

Identification of a testis-enriched heat shock protein and fourteen members of Hsp70 family in the swamp eel.

PubMed

He, Yan; Luo, Majing; Yi, Minhan; Sheng, Yue; Cheng, Yibin; Zhou, Rongjia; Cheng, Hanhua

2013-01-01

Gonad differentiation is one of the most important developmental events in vertebrates. Some heat shock proteins are associated with gonad development. Heat shock protein 70 (Hsp70) in the teleost fish and its roles in sex differentiation are poorly understood. We have identified a testis-enriched heat shock protein Hspa8b2 in the swamp eel using Western blot analysis and Mass Spectrometry (MS). Fourteen Hsp70 family genes were further identified in this species based on transcriptome information. The phylogenetic tree of Hsp70 family was constructed using the Maximum Likelihood method and their expression patterns in the swamp eel gonads were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). There are fourteen gene members in the Hsp70 family in the swamp eel genome. Hsp70 family, particularly Hspa8, has expanded in the species. One of the family members Hspa8b2 is predominantly expressed in testis of the swamp eel.

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.

Progesterone as a bone-trophic hormone.

PubMed

Prior, J C

1990-05-01

Experimental, epidemiological, and clinical data indicate that progesterone is active in bone metabolism. Progesterone appears to act directly on bone by engaging an osteoblast receptor or indirectly through competition for a glucocorticoid osteoblast receptor. Progesterone seems to promote bone formation and/or increase bone turnover. It is possible, through estrogen-stimulated increased progesterone binding to the osteoblast receptor, that progesterone plays a role in the coupling of bone resorption with bone formation. A model of the interdependent actions of progesterone and estrogen on appropriately-"ready" cells in each bone multicellular unit can be tied into the integrated secretions of these hormones within the ovulatory cycle. Figure 5 is an illustration of this concept. It shows the phases of the bone remodeling cycle in parallel with temporal changes in gonadal steroids across a stylized ovulatory cycle. Increasing estrogen production before ovulation may reverse the resorption occurring in a "sensitive" bone multicellular unit while gonadal steroid levels are low at the time of menstrual flow. The bone remodeling unit would then be ready to begin a phase of formation as progesterone levels peaked in the midluteal phase. From this perspective, the normal ovulatory cycle looks like a natural bone-activating, coherence cycle. Critical analysis of the reviewed data indicate that progesterone meets the necessary criteria to play a causal role in mineral metabolism. This review provides the preliminary basis for further molecular, genetic, experimental, and clinical investigation of the role(s) of progesterone in bone remodeling. Much further data are needed about the interrelationships between gonadal steroids and the "life cycle" of bone. Feldman et al., however, may have been prophetic when he commented; "If this anti-glucocorticoid effect of progesterone also holds true in bone, then postmenopausal osteoporosis may be, in part, a progesterone deficiency disease."

The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1)

PubMed Central

Wolfe, Andrew; Divall, Sara; Wu, Sheng

2014-01-01

The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. PMID:24929098

The Role of Cholesterol Utilization in a Computational Adrenal Steroidogenesis Model to Improve Predictability of Biochemical Responses to Endocrine Active Chemicals

EPA Science Inventory

Steroids, which have an important role in a wide range of physiological processes, are synthesized primarily in the gonads and adrenal glands through a series of enzyme-mediated reactions. The activity of steroidogenic enzymes can be altered by a variety of endocrine active chem...

The Role of Oxysterols in a Computational Steroidogenesis Model of Human H295R Cells to Improve Predictability of Biochemical Responses to Endocrine Disruptors

EPA Science Inventory

Steroids, which have an important role in a wide range of physiological processes, are synthesized primarily in the gonads and adrenal glands through a series of enzyme mediated reactions. The activity of steroidogenic enzymes can be altered by a variety of endocrine disruptors (...

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

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

PubMed

Imai, Takuto; Saino, Kentaro; Matsuda, Masaru

2015-11-06

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. Copyright © 2015 Elsevier Inc. All rights reserved.

The X linked recessive form of XY gonadal dysgenesis with a high incidence of gonadal germ cell tumours: clinical and genetic studies.

PubMed

Mann, J R; Corkery, J J; Fisher, H J; Cameron, A H; Mayerová, A; Wolf, U; Kennaugh, A A; Woolley, V

1983-08-01

Five phenotypic females in one family had the genotype 46,XY and all had gonadal germ cell tumours. Studies of the family pedigree suggest that this form of XY gonadal dysgenesis is inherited in an X linked recessive manner. G banding of elongated metaphase chromosomes from two subjects with XY gonadal dysgenesis and a female carrier showed no aberrations of the X chromosome. The titres of H-Y antigen in three girls with XY gonadal dysgenesis were in the male control range. Thus it appears that, in the X linked form, XY gonadal dysgenesis may be caused by a point deletion or mutation of a gene on the X chromosome, which controls the gonad specific receptor for the H-Y antigen. Studies of Xg blood groups were uninformative about linkage of Xg with the X borne gene causing the XY gonadal dysgenesis. Dermatoglyphic studies in the girls with XY gonadal dysgenesis and female carriers revealed high a-b palmar ridge counts and a tendency for the A mainline to terminate in the thenar area. Both of these features have been described in patients with Turner's syndrome.

Steroidogenic Factor-1 and Human Disease

PubMed Central

El-Khairi, Ranna; Achermann, John C.

2016-01-01

Steroidogenic factor-1 (SF-1) (Ad4BP, NR5A1) is a nuclear receptor that plays a key role in adrenal and reproductive development and function. Deletion of the gene encoding Sf-1 (Nr5a1) in mice results in severe developmental defects of the adrenal gland and gonad. Consequently, initial work on the potential effects of SF-1 disruption in humans focused on individuals with primary adrenal failure, a 46,XY karyotype, complete gonadal dysgenesis, and Müllerian structures. This is a rare phenotype, but has been reported on two occasions, because of alterations that affect key DNA-binding domains of SF-1. Attention then turned to a potential wider role of SF-1 in human adrenal and reproductive disorders. Although changes in SF-1 only very rarely cause isolated adrenal failure, it is emerging that variations in SF-1 are a surprisingly frequent cause of reproductive dysfunction in humans. In 46,XY disorders of sex development, a spectrum of phenotypes has been reported including severe and partial forms of gonadal (testicular) dysgenesis, hypospadias, anorchia with microphallus, and even male factor infertility. In 46,XX females, alterations in SF-1 are associated with primary ovarian insufficiency. Thus, SF-1 seems be a more significant factor in human reproductive health than was first envisioned, with implications for adults as well as children. PMID:23044873

Molecular cloning of cytochrome P450 side-chain cleavage and changes in its mRNA expression during gonadal development of brown hagfish, Paramyxine atami.

PubMed

Nishiyama, Maki; Uchida, Katsuhisa; Abe, Nozomi; Nozaki, Masumi

2015-02-01

Since hagfishes are considered the most primitive vertebrate known, extant or extinct, studies on their reproduction are indispensable for understanding phylogenetic aspects of vertebrate reproduction. However, little information is available on the endocrine regulation of the gonadal function in the hagfish. Based on EST analysis of the testis of the brown hagfish (Paramyxine atami), P450 side chain cleavage (CYP11A), which is the first and essential enzyme for steroidogenesis in jawed vertebrates, was cloned. The deduced amino acid sequence of hagfish CYP11A shows high identity to other animal forms especially in two functional domains, adrenodoxin binding domain and heme-binding domain. In the phylogenetic analysis, hagfish CYP11A forms a clade with the vertebrate CYP11A. Following the real-time PCR analysis, CYP11A mRNA expression levels were clearly correlated to the developmental stages of gonads in both sexes of the brown hagfish. By in situ hybridization, CYP11A mRNA signals were found in the theca cells of the ovarian follicles and Leydig cells and the tubule-boundary cells of the testis. These molecular and histological evidences are suggesting that CYP11A plays functional roles as a steroidogenic enzyme in gonadal development. Moreover, native GTH purified from hagfish pituitary stimulated the transcriptional levels of CYP11A in the organ-cultured testis in vitro, clearly suggesting that the steroidogenic activity of the hagfish is under the control of the pituitary GTH. It is suggested that vertebrates, during their early evolution, have established the pituitary-gonadal reproductive system. Copyright © 2015 Elsevier Inc. All rights reserved.

The platelet-derived growth factor signaling system in snapping turtle embryos, Chelydra serpentina: potential role in temperature-dependent sex determination and testis development.

PubMed

Rhen, Turk; Jangula, Adam; Schroeder, Anthony; Woodward-Bosh, Rikki

2009-05-01

The platelet-derived growth factor (Pdgf) signaling system is known to play a significant role during embryonic and postnatal development of testes in mammals and birds. In contrast, genes that comprise the Pdgf system in reptiles have never been cloned or studied in any tissue, let alone developing gonads. To explore the potential role of PDGF ligands and their receptors during embryogenesis, we cloned cDNA fragments of Pdgf-A, Pdgf-B, and receptors PdgfR-alpha and PdgfR-beta in the snapping turtle, a reptile with temperature-dependent sex determination (TSD). We then compared gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature, as well as between hatchling testes and ovaries. Expression of Pdgf-B mRNA in embryonic gonads was significantly higher at a male temperature than at a female temperature, but there was no difference between hatchling testes and ovaries. This developmental pattern was reversed for Pdgf-A and PdgfR-alpha mRNA: expression of these genes did not differ in embryos, but diverged in hatchling testes and ovaries. Levels of PdgfR-beta mRNA in embryonic gonads were not affected by temperature and did not differ between testes and ovaries. However, expression of both receptors increased at least an order of magnitude from the embryonic to the post-hatching period. Finally, we characterized expression of these genes in several other embryonic tissues. The brain, heart, and liver displayed unique expression patterns that distinguished these tissues from each other and from intestine, lung, and muscle. Incubation temperature had a significant effect on expression of PdgfR-alpha and PdgfR-beta in the heart but not other tissues. Together, these findings demonstrate that temperature has tissue specific effects on the Pdgf system and suggest that Pdgf signaling is involved in sex determination and the ensuing differentiation of testes in the snapping turtle.

The platelet-derived growth factor signaling system in snapping turtle embryos, Chelydra serpentina: potential role in temperature-dependent sex determination and testis development

PubMed Central

Rhen, Turk; Jangula, Adam; Schroeder, Anthony; Woodward-Bosh, Rikki

2009-01-01

The platelet-derived growth factor (Pdgf) signaling system is known to play a significant role during embryonic and postnatal development of testes in mammals and birds. In contrast, genes that comprise the Pdgf system in reptiles have never been cloned or studied in any tissue, let alone developing gonads. To explore the potential role of PDGF ligands and their receptors during embryogenesis, we cloned cDNA fragments of Pdgf-A, Pdgf-B, and receptors PdgfR-α and PdgfR-β in the snapping turtle, a reptile with temperature-dependent sex determination (TSD). We then compared gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature, as well as between hatchling testes and ovaries. Expression of Pdgf-B mRNA in embryonic gonads was significantly higher at a male temperature than at a female temperature, but there was no difference between hatchling testes and ovaries. This developmental pattern was reversed for Pdgf-A and PdgfR-α mRNA: expression of these genes did not differ in embryos, but diverged in hatchling testes and ovaries. Levels of PdgfR-β mRNA in embryonic gonads were not affected by temperature and did not differ between testes and ovaries. However, expression of both receptors increased at least an order of magnitude from the embryonic to the post-hatching period. Finally, we characterized expression of these genes in several other embryonic tissues. The brain, heart, and liver displayed unique expression patterns that distinguished these tissues from each other and from intestine, lung, and muscle. Incubation temperature had a significant effect on expression of PdgfR-α and PdgfR-β in the heart but not other tissues. Together, these findings demonstrate that temperature has tissue specific effects on the Pdgf system and suggest that Pdgf signaling is involved in sex determination and the ensuing differentiation of testes in the snapping turtle. PMID:19523392

Cytoplasmic and nuclear localization of cadherin in honey bee (Apis mellifera L.) gonads.

PubMed

Florecki, Mônica M; Hartfelder, Klaus

2011-01-01

Cadherins are crucial molecules mediating cell-cell interactions between somatic and germline cells in insect and mammalian male and female gonads. We analysed the presence and localization of cadherins in ovaries of honeybee queens and in testes of drones. Transcripts representing two classical cadherins, E-cadherin (shotgun) and N-cadherin, as well as three protocadherins (Starry night, Fat and Fat-like) were detected in gonads of both sexes. Pan-cadherin antibodies, which most probably detect a honeybee N-cadherin, were used in immunolocalization analyses. In the germarium of ovarioles, cadherin-IR (cadherin immunoreactivity) was evidenced as homogeneously distributed in the cytoplasm and as nuclear foci, in both germline and somatic cells. It was also detected in polyfusomes and ring canals. In testiolar tubules, cadherin-IR showed a cytoplasmic and nuclear distributon alike in ovaries. The unexpected nuclear localization and cytoplasmic distribution in ovaries and testes were corroborated by immunogold electron microscopy, which revealed cadherin aggregates associated with electron-dense nuclear structures. With respect to cadherin localization, the honeybee differs from Drosophila, the model for gametogenesis in insects, raising the question as to how differences among solitary and social species may be built into and generated from the general architecture of polytrophic meroistic ovaries. It also indicates the possibility of divergent roles for cadherin in the functional architecture of insect gonads, in general, especially in taxa with high reproductive output.

The para-aortic ridge plays a key role in the formation of the renal, adrenal and gonadal vascular systems

PubMed Central

Isogai, Sumio; Horiguchi, Mayuko; Hitomi, Jiro

2010-01-01

Renal, adrenal, gonadal, ureteral and inferior phrenic arteries vary in their level of origin and in their calibre, number and precise anatomical relationship to other structures. Studies of the origin and early development of these arteries have evoked sharp disputes. The ladder theory of Felix, which states that ‘All the mesonephric arteries may persist; from them are formed the phrenic, suprarenal, renal and internal spermatic arteries’ has been generally quoted in the anatomical textbooks without rigorous verification for 100 years. In this study, we re-examined this theory by performing micro-injection of dye and resin into rat (Rattus norvegicus) embryos. Our results revealed that most of the mesonephric arteries had degenerated before the metanephros started its ascent. The definitive renal, adrenal, gonadal, ureteral and inferior phrenic arteries appeared as new branches from the gonadal artery and/or directly from the abdominal aorta to the para-aortic ridge. Coincidental to this, the anatomical architecture of the inter-renal vascular cage, which consists of the interlobar and arcuate arteries and their collateral veins, was completed within the developing metanephros. We demonstrated that the delicate renal vascular cage switched from the primary renal artery to the definitive renal artery and that the route of venous drainage changed from the posterior cardinal vein to the inferior (caudal) vena cava. PMID:20579173

nr0b1 (DAX1) mutation in zebrafish causes female-to-male sex reversal through abnormal gonadal proliferation and differentiation.

PubMed

Chen, Sijie; Zhang, Hefei; Wang, Fenghua; Zhang, Wei; Peng, Gang

2016-09-15

Sex determinations are diverse in vertebrates. Although many sex-determining genes and pathways are conserved, the mechanistic roles of these genes and pathways in the genetic sex determination are not well understood. DAX1 (encoded by the NR0B1 gene) is a vertebrate specific orphan nuclear receptor that regulates gonadal development and sexual determination. In human, duplication of the NR0B1 gene leads to male-to-female sex reversal. In mice, Nr0b1 shows both pro-testis and anti-testis functions. We generated inheritable nr0b1 mutation in the zebrafish and found the nr0b1 mutation caused homozygous mutants to develop as fertile males due to female-to-male sex reversal. The nr0b1 mutation did not increase Caspase-3 labeling nor tp53 expression in the developing gonads. Introduction of a tp53 mutation into the nr0b1 mutant did not rescue the sex-reversal phenotype. Further examination revealed reduction in cell proliferation and abnormal somatic cell differentiation in the nr0b1 mutant gonads at the undifferentiated and bi-potential ovary stages. Together, our results suggest nr0b1 regulates somatic cell differentiation and cell proliferation to ensure normal sex development in the zebrafish. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Reproductive neuropeptides that stimulate spawning in the Sydney Rock Oyster (Saccostrea glomerata).

PubMed

In, Vu Van; Ntalamagka, Nikoleta; O'Connor, Wayne; Wang, Tianfang; Powell, Daniel; Cummins, Scott F; Elizur, Abigail

2016-08-01

The Sydney Rock Oyster, Saccostrea glomerata, is a socioeconomically important species in Australia, yet little is known about the molecular mechanism that regulates its reproduction. To address this gap, we have performed a combination of high throughput transcriptomic and peptidomic analysis, to identify genes and neuropeptides that are expressed in the key regulatory tissues of S. glomerata; the visceral ganglia and gonads. Neuropeptides are known to encompass a diverse class of peptide messengers that play functional roles in many aspects of an animal's life, including reproduction. Approximately 28 neuropeptide genes were identified, primarily within the visceral ganglia transcriptome, that encode precursor proteins containing numerous neuropeptides; some were confirmed through mass spectral peptidomics analysis of the visceral ganglia. Of those, 28 bioactive neuropeptides were synthesized, and then tested for their capacity to induce gonad development and spawning in S. glomerata. Egg laying hormone, gonadotropin-releasing hormone, APGWamide, buccalin, CCAP and LFRFamide were neuropeptides found to trigger spawning in ripe animals. Additional testing of APGWa and buccalin demonstrated their capacity to advance conditioning and gonadal maturation. In summary, our analysis of S. glomerata has identified neuropeptides that can influence the reproductive cycle of this species, specifically by accelerating gonadal maturation and triggering spawning. Other molluscan neuropeptides identified in this study will enable further research into understanding the neuroendocrinology of oysters, which may benefit their cultivation. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Mass and energy budgets of animals: behavioral and ecological implications. Progress report, December 1, 1984-July 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, W.P.

1985-08-01

We continue to put considerable effort into analysis of the dynamics of interactions between environmental and animal variance and its implications for growth and reproduction. We have completed the physiological experiments necessary for defining a complete mass and energy budget for two species of lizards, Uta stansburiana, and Sceloporus undulatus. We have completed the programming and are evaluating calculations for potential growth and reproduction for Sceloporus undulatus for the sandhill country of western Nebraska, where we have field data on microclimates, doubly labeled water measurements, and growth and reproduction measurements to do a thorough test of the microclimate and ectothermmore » models that together calculate potential growth and reproduction. The doubly labeled water analysis system is calibrated and running very well. We are just beginning analysis of the lizard samples from Nebraska. In deer mice, marmots and prairie dogs we have found significant diurnal and seasonal changes in body temperature and activity times. Deer mice in the field may exhibit 6-7 degree and as much as 20 degree body temperature changes in 15 to 20 minute intervals. Winter work in Jackson Hole at -40C showed capability for core temperature drops in deer mice of 8C in one minute and full recovery once the animal could burrow into the snow. Our calculations show that this variability saves significantly in energy costs.« less

Immune responses of eastern fence lizards (Sceloporus undulatus) to repeated acute elevation of corticosterone.

PubMed

McCormick, Gail L; Langkilde, Tracy

2014-08-01

Prolonged elevations of glucocorticoids due to long-duration (chronic) stress can suppress immune function. It is unclear, however, how natural stressors that result in repeated short-duration (acute) stress, such as frequent agonistic social encounters or predator attacks, fit into our current understanding of the immune consequences of stress. Since these types of stressors may activate the immune system due to increased risk of injury, immune suppression may be reduced at sites where individuals are repeatedly exposed to potentially damaging stressors. We tested whether repeated acute elevation of corticosterone (CORT, a glucocorticoid) suppresses immune function in eastern fence lizards (Sceloporus undulatus), and whether this effect varies between lizards from high-stress (high baseline CORT, invaded by predatory fire ants) and low-stress (low baseline CORT, uninvaded) sites. Lizards treated daily with exogenous CORT showed higher hemagglutination of novel proteins by their plasma (a test of constitutive humoral immunity) than control lizards, a pattern that was consistent across sites. There was no significant effect of CORT treatment on bacterial killing ability of plasma. These results suggest that repeated elevations of CORT, which are common in nature, produce immune effects more typical of those expected at the acute end of the acute-chronic spectrum and provide no evidence of modulated consequences of elevated CORT in animals from high-stress sites. Copyright © 2014 Elsevier Inc. All rights reserved.

Formant-frequency discrimination of synthesized vowels in budgerigars (Melopsittacus undulatus) and humans.

PubMed

Henry, Kenneth S; Amburgey, Kassidy N; Abrams, Kristina S; Idrobo, Fabio; Carney, Laurel H

2017-10-01

Vowels are complex sounds with four to five spectral peaks known as formants. The frequencies of the two lowest formants, F1and F2, are sufficient for vowel discrimination. Behavioral studies show that many birds and mammals can discriminate vowels. However, few studies have quantified thresholds for formant-frequency discrimination. The present study examined formant-frequency discrimination in budgerigars (Melopsittacus undulatus) and humans using stimuli with one or two formants and a constant fundamental frequency of 200 Hz. Stimuli had spectral envelopes similar to natural speech and were presented with random level variation. Thresholds were estimated for frequency discrimination of F1, F2, and simultaneous F1 and F2 changes. The same two-down, one-up tracking procedure and single-interval, two-alternative task were used for both species. Formant-frequency discrimination thresholds were as sensitive in budgerigars as in humans and followed the same patterns across all conditions. Thresholds expressed as percent frequency difference were higher for F1 than for F2, and were unchanged between stimuli with one or two formants. Thresholds for simultaneous F1 and F2 changes indicated that discrimination was based on combined information from both formant regions. Results were consistent with previous human studies and show that budgerigars provide an exceptionally sensitive animal model of vowel feature discrimination.

Study of an outbreak of ciguatera fish poisoning in Hong Kong.

PubMed

Wong, Chun-Kwan; Hung, Patricia; Lee, Kellie L H; Kam, Kai-Man

2005-10-01

Ciguatera fish poisoning (CFP) has been a significant and increasing public health problem in Hong Kong since 1980s. With growing demand for imported live coral fishes, the number of people who suffered from this disease has also been increasing. An outbreak of CFP in 2004 was the second most prominent in record as compared with the most significant one that occurred in 1998. In 2004, out of a total of 823 reported food poisoning outbreaks involving 3159 persons, 65 incidents (7.9%) affecting 247 people (7.8%) were attributed to CFP. Validated mouse bioassay analysis of surveillance samples revealed that seven samples (13%) were confirmed to be contaminated with ciguatoxins (CTXs). Typical symptoms of CTXs were found in mice injected with 20mg of fish extracts. The causative fishes included Cheilinus undulatus, Epinephelus coioides, Plectropomus areolatus, and Plectropomus leopardus. Most of these CTX-positive samples analyzed had only trace amounts of CTXs in their extract, except a C. undulatus sample which contained a mice lethal dose (2.5MU/20mg ether extract). This fish species was also the major origin of coral fish that caused clusters of CFP in the last quarter of 2004. Cigua-Check analysis of 20 flesh grains from seven CTX-positive fishes, previously confirmed as CTX-positive samples by mouse bioassay, showed that 50% of flesh grains were CTX contaminated.

Tumor risk of children with 45,X/46,XY gonadal dysgenesis in relation to their clinical presentations: Further insights into the gonadal management.

PubMed

Tam, Yuk Him; Wong, Yuen Shan; Pang, Kristine Kit Yi; To, Ka Fai; Yiu, Alice Ka Wah; Wong, Hei Yi; Tsui, Siu Yan; Mou, Jennifer Wai Cheung; Chan, Kin Wai; Lee, Kim Hung

2016-09-01

To investigate the risk of gonadal germ cell neoplasms (GCN) in children with 45,X/46,XY gonadal dysgenesis and its relation to the clinical presentations. We conducted a retrospective study reviewing the clinical and gonadal features of all consecutive children with 45,X/46,XY gonadal dysgenesis who received gonadal management in a tertiary center from 1985 to 2015. Study subjects were divided into Group I(significant genitalia anomaly), Group II(female phenotype) and Group III(male phenotype). 21 children were studied (Group I=8; Group II=11; Group III=2). All 19 children of Group I and II eventually underwent bilateral gonadectomy. One patient of Group III underwent gonadal biopsy which showed increase in fibrous tissue in the testes without any GCN. 3/8(37.5%) and 6/11(54.5%) of patients in Group I and II respectively had either gonadoblastoma (GB) or carcinoma-in-situ (CIS) or both affecting one or both gonads. Among Group I patients, the 4 dysgenetic testes affected by CIS in 3 patients were intraabdominal (n=1), inguinal (n=1) and scrotal (n=2) in positions. Among Group II patients, 6/20 streak gonads had GB and 2/2 dysgenetic testes had GB or CIS. 45,X/46,XY children with significant genitalia anomaly or female phenotype are both at high risk of gonadal GCN. Copyright © 2016 Elsevier Inc. All rights reserved.

Expression of three gonadotropin subunits and gonadotropin receptor mRNA during male-to-female sex change in the cinnamon clownfish, Amphiprion melanopus.

PubMed

An, Kwang Wook; Lee, Jehee; Choi, Cheol Young

2010-08-01

To quantify the sex-change progression from male to female in the cinnamon clownfish, Amphiprion melanopus, we divided gonadal development into three stages (I, mature male; II, male at 90 days after removal of the female; and III, mature female), and the expression of GTH subunits and GTH receptors during each of these stages was investigated. The mRNA of the three GTH subunits and their receptors increased with progression from male to female. To understand the effect of gonadotropin-releasing hormone (GnRH) on this progression, we examined expression of genes encoding the GTH subunit mRNA in the pituitary and the GTH-receptor mRNA in the gonads in addition to investigating changes in plasma E(2) levels after GnRH analogue (GnRHa) injection. GnRHa treatment increased mRNA expression levels of these genes, as well as plasma E(2) levels, indicating that GnRH plays an important regulatory role in the brain-pituitary-gonad axis of immature cinnamon clownfish. Copyright (c) 2010 Elsevier Inc. All rights reserved.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

γ-Amino-butyric acid (GABA) receptor subunit and transporter expression in the gonad and liver of the fathead minnow (Pimephales promelas).

PubMed

Biggs, Katie; Seidel, Jason S; Wilson, Alex; Martyniuk, Christopher J

2013-09-01

γ-Amino-butyric acid (GABA) is the major inhibitory neurotransmitter in the vertebrate central nervous system. GABA receptors and synthesizing enzymes have also been localized to peripheral tissues including the liver, oviduct, uterus and ovary of mammals but the distribution and role of GABA in peripheral tissues of fish has not been fully investigated. The objectives of this study were to (1) determine if mRNA encoding GABA synthesizing enzymes (glutamic acid decarboxylase 65 and 67; gad65 and gad67), GABA transporters, and GABAA receptor subunits are localized to liver and gonad of fathead minnow (Pimephales promelas) (FHM) (2) investigate the effects of GABA on ovarian 17β-estradiol (E2) production, and (3) measure transcript responses in the ovary after in vitro incubation to GABA. Real-time PCR assays were developed for gad65, gad67, vesicular GABA transporter (vgat) and GABA transporter 1 (gat1), and select GABAA receptor subunits (gabra1, gabra5, gabrb1, gabrb2, gabrg1, gabrg2). All transcripts were localized to the brain as expected; however transcripts were also detected in the liver, ovary, and testis of FHMs. In the female liver, gad65 mRNA was significantly higher in expression compared to the male liver. Transcripts for gad67 were the highest in the brain>gonad>liver and in the gonads, gad67 was significantly higher in expression than gad65 mRNA. In the liver and gonad, the relative abundance of the subunits followed a general trend of gabrb1>gabrb2=gabrg1=gabrg2>gabra1=gabra5. To explore the effects of GABA in the ovary, tissue explants from reproductive female FHMs were treated with GABA (10(-10), 10(-8) and 10(-6)M) for 12h. GABA had no significant effect on 17β-estradiol production or on mRNA abundance for genes involved in ovarian steroidogenesis (e.g., 11βhsd, cyp17, cyp19a). There was a significant decrease in estrogen receptor 2a (esr2a) mRNA with 10(-10)M GABA. This study begins to investigate the GABA system in non-neural tissues of teleost fish and addresses the broader topic regarding the peripheral roles of neurotransmitters. Copyright © 2013 Elsevier Inc. All rights reserved.

Genome-wide identification, phylogeny, and gonadal expression of fox genes in Nile tilapia, Oreochromis niloticus.

PubMed

Yuan, Jing; Tao, Wenjing; Cheng, Yunying; Huang, Baofeng; Wang, Deshou

2014-08-01

The fox genes play important roles in various biological processes, including sexual development. In the present study, we isolated 65 fox genes, belonging to 18 subfamilies named A-R, from Nile tilapia through genome-wide screening. Twenty-four of them have two or three (foxm1) copies. Furthermore, 16, 25, 68, and 45 fox members were isolated from nematodes, protochordates, teleosts, and tetrapods, respectively. Phylogenetic analyses indicated fox gene family had undergone three expansions parallel to the three rounds of genome duplication during evolution. We also analyzed the clustered fox genes and found that apparent linkage duplication existed in teleosts, which further supported fish-specific genome duplication hypothesis. In addition, species- and lineage-specific duplication is another reason for fox gene family expansion. Based on the four pairs of XX and XY gonadal transcriptome data from four critical developmental stages, we analyzed the expression profile of all fox genes and identified sexually dimorphic fox genes at each stage. All fox genes were detected in gonads, with 15 of them at the background expression level (total read per kb per million reads, RPKM < 10), 29 at moderate expression level (10 < total RPKM < 100), and 21 at high expression level (total RPKM > 100). There are 27, 24, 28, and 9 sexually dimorphic fox genes at 5, 30, 90, and 180 days after hatching (dah), respectively. foxq1a, foxf1, foxr1, and foxr1 were identified as the most differentially expressed genes at each stage. foxl2 was characterized as XX-dominant gene, while foxd5, foxi3, foxn3, foxj1a, foxj3b, and foxo6b were characterized as XY-dominant genes. qPCR and in situ hybridization of foxh1 and foxj1a were performed to confirm the expression profiles and to validate the transcriptome data. Our results suggest that fox genes might play important roles in sex determination and gonadal development in teleosts.

Effects of the insecticide fipronil on reproductive endocrinology in the fathead minnow

EPA Science Inventory

Gamma aminobutyric acid (GABA) and GABA receptors play an important role in neuroendocrine regulation in fish. Disruption of the GABAergic system by environmental contaminants could interfere with normal regulation of the hypothalamic pituitary gonadal (HPG) axis, leading to imp...

Female gonadal shielding with automatic exposure control increases radiation risks.

PubMed

Kaplan, Summer L; Magill, Dennise; Felice, Marc A; Xiao, Rui; Ali, Sayed; Zhu, Xiaowei

2018-02-01

Gonadal shielding remains common, but current estimates of gonadal radiation risk are lower than estimated risks to colon and stomach. A female gonadal shield may attenuate active automatic exposure control (AEC) sensors, resulting in increased dose to colon and stomach as well as to ovaries outside the shielded area. We assess changes in dose-area product (DAP) and absorbed organ dose when female gonadal shielding is used with AEC for pelvis radiography. We imaged adult and 5-year-old equivalent dosimetry phantoms using pelvis radiograph technique with AEC in the presence and absence of a female gonadal shield. We recorded DAP and mAs and measured organ absorbed dose at six internal sites using film dosimetry. Female gonadal shielding with AEC increased DAP 63% for the 5-year-old phantom and 147% for the adult phantom. Absorbed organ dose at unshielded locations of colon, stomach and ovaries increased 21-51% in the 5-year-old phantom and 17-100% in the adult phantom. Absorbed organ dose sampled under the shield decreased 67% in the 5-year-old phantom and 16% in the adult phantom. Female gonadal shielding combined with AEC during pelvic radiography increases absorbed dose to organs with greater radiation sensitivity and to unshielded ovaries. Difficulty in proper use of gonadal shields has been well described, and use of female gonadal shielding may be inadvisable given the risks of increasing radiation.

Loss of Mitogen-Activated Protein Kinase Kinase Kinase 4 (MAP3K4) Reveals a Requirement for MAPK Signalling in Mouse Sex Determination

PubMed Central

Bogani, Debora; Siggers, Pam; Brixey, Rachel; Warr, Nick; Beddow, Sarah; Edwards, Jessica; Williams, Debbie; Wilhelm, Dagmar; Koopman, Peter; Flavell, Richard A.; Chi, Hongbo; Ostrer, Harry; Wells, Sara; Cheeseman, Michael; Greenfield, Andy

2009-01-01

Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY) gonad, sex-determining region of the Y (SRY) protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK) signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg) mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4), a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas). These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and create a novel entry point into the molecular and cellular mechanisms underlying sex determination in mice and disorders of sexual development in humans. PMID:19753101

Retinoic Acid Metabolic Genes, Meiosis, and Gonadal Sex Differentiation in Zebrafish

PubMed Central

Rodríguez-Marí, Adriana; Cañestro, Cristian; BreMiller, Ruth A.; Catchen, Julian M.; Yan, Yi-Lin; Postlethwait, John H.

2013-01-01

To help understand the elusive mechanisms of zebrafish sex determination, we studied the genetic machinery regulating production and breakdown of retinoic acid (RA) during the onset of meiosis in gonadogenesis. Results uncovered unexpected mechanistic differences between zebrafish and mammals. Conserved synteny and expression analyses revealed that cyp26a1 in zebrafish and its paralog Cyp26b1 in tetrapods independently became the primary genes encoding enzymes available for gonadal RA-degradation, showing lineage-specific subfunctionalization of vertebrate genome duplication (VGD) paralogs. Experiments showed that zebrafish express aldh1a2, which encodes an RA-synthesizing enzyme, in the gonad rather than in the mesonephros as in mouse. Germ cells in bipotential gonads of all zebrafish analyzed were labeled by the early meiotic marker sycp3, suggesting that in zebrafish, the onset of meiosis is not sexually dimorphic as it is in mouse and is independent of Stra8, which is required in mouse but was lost in teleosts. Analysis of dead-end knockdown zebrafish depleted of germ cells revealed the germ cell-independent onset and maintenance of gonadal aldh1a2 and cyp26a1 expression. After meiosis initiated, somatic cell expression of cyp26a1 became sexually dimorphic: up-regulated in testes but not ovaries. Meiotic germ cells expressing the synaptonemal complex gene sycp3 occupied islands of somatic cells that lacked cyp26a1 expression, as predicted by the hypothesis that Cyp26a1 acts as a meiosis-inhibiting factor. Consistent with this hypothesis, females up-regulated cyp26a1 in oocytes that entered prophase-I meiotic arrest, and down-regulated cyp26a1 in oocytes resuming meiosis. Co-expression of cyp26a1 and the pluripotent germ cell stem cell marker pou5f1(oct4) in meiotically arrested oocytes was consistent with roles in mouse to promote germ cell survival and to prevent apoptosis, mechanisms that are central for tipping the sexual fate of gonads towards the female pathway in zebrafish. PMID:24040125

Normal pelvic ultrasound or MRI does not rule out neoplasm in patients with gonadal dysgenesis and Y chromosome material.

PubMed

Ebert, Kristin M; Hewitt, Geri D; Indyk, Justin A; McCracken, Katherine A; Nahata, Leena; Jayanthi, Venkata R

2018-04-01

Patients with gonadal dysgenesis (GD) with a Y chromosome have an increased risk of gonadal neoplasm. Few data exist on the ability of imaging to detect malignancy in intra-abdominal gonads in these patients. We aimed to determine the correlation between preoperative imaging findings and gonadal pathology in GD patients with Y chromosome material. A retrospective review was performed of patients with XY or XO/XY GD who underwent gonadectomy at our institution from 2003 to 2017. Patients were assessed preoperatively with ultrasonography; some additionally underwent MRI. The series consisted of 10 patients, all with female gender and non-palpable gonads. Median age was 13.1 years (range 2.4-18.3 years). Overall, four of the ten patients (40%) had a tumor (gonadoblastoma or dysgerminoma) on final pathology. Four patients had a gonad or gonads that were definitively seen on ultrasonography. All visualized gonads were described as "normal" or "small" with the exception of one patient, who had a normal MRI. Three of the four patients in this group had a tumor on final pathology. The remaining six patients had a gonad or gonads that were not definitively visualized on ultrasound; one patient in this group had a tumor on final pathology. Overall, five of seven gonads (71%) definitively visualized on ultrasound had tumor on final pathology, and two of thirteen gonads (15%) not visualized on ultrasound had tumor on final pathology; this difference was statistically significant (p = 0.012). Three patients were imaged with MRI. Of the gonads that could be visualized on MRI, no definitive abnormalities were seen. All patients imaged with MRI had tumors on final pathology. Both ultrasound and MRI are relatively poor at identifying and characterizing intra-abdominal gonads in GD patients. The majority of patients who had a neoplasm had normal imaging findings. Gonads that were definitively visualized on ultrasound were more likely to contain neoplasms that could not be visualized, which perhaps because of tumor growth. No other consistent imaging findings of malignancy were found. Our study included ultrasound evaluations that were completed over 10 years ago and not performed by pediatric ultrasonographers, which may have biased the results. However, results suggest that when discussing gonadectomy with GD patients, one should not be reassured by "normal" imaging findings. Neither ultrasound nor MRI should be relied on for surveillance in GD patients who decide against gonadectomy. A normal ultrasound or MRI does not rule out neoplasm in GD patients with intra-abdominal gonads. Copyright © 2017 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

[Pure gonad dysgenesia or Swyer sindrome. A case report having tumoral development: melanoma].

PubMed

Russo, D; Blanco, M; Falke, G; Rocca Rivarola, M; Séller, R; Puigdevall, J C; Bergada, C

2006-10-01

A 14 year old girl having 10-days lumbar pain, polaquiuria and moderate pain to palpation is reported. Blood and urine analysis were normal. Abdominal ultrasound scan showed cavity free and solid, rounded, heterogeneous, intrapelvic mass compressing bladder and uterus. Magnetic resonance image was performed showing right gonad compromise with extensive liver and sacro-lumbar spine invasion. Tumoral markers were ruled out. During surgery, primary tumor mass localizad in the right gonad was completely excised. Melanotic peritoneal and hepatic disemination were observed. The patient had left streak gonad and infantile uterus (2 x 3 cm). As gonad dysgenesia was suspected, high resolution cromosomic study was performed and resulted in cariotype 46 XY. Microscopy of the resected gonad showed primary gonad melanoma. Chemotherapy was instituted with no tumor response and the patient died two month later.

Dynamic and differential expression of the gonadal aromatase during the process of sexual differentiation in a novel transgenic cyp19a1a-eGFP zebrafish line.

PubMed

Hinfray, Nathalie; Sohm, Frédéric; Caulier, Morgane; Chadili, Edith; Piccini, Benjamin; Torchy, Camille; Porcher, Jean-Marc; Guiguen, Yann; Brion, François

2018-05-15

In zebrafish, there exists a clear need for new tools to study sex differentiation dynamic and its perturbation by endocrine disrupting chemicals. In this context, we developed and characterized a novel transgenic zebrafish line expressing green fluorescent protein (GFP) under the control of the zebrafish cyp19a1a (gonadal aromatase) promoter. In most gonochoristic fish species including zebrafish, cyp19a1a, the enzyme responsible for the synthesis of estrogens, has been shown to play a critical role in the processes of reproduction and sexual differentiation. This novel cyp19a1a-eGFP transgenic line allowed a deeper characterization of expression and localization of cyp19a1a gene in zebrafish gonads both at the adult stage and during development. At the adult stage, GFP expression was higher in ovaries than in testis. We showed a perfect co-expression of GFP and endogenous Cyp19a1a protein in gonads that was mainly localized in the cytoplasm of peri-follicular cells in the ovary and of Leydig and germ cells in the testis. During development, GFP was expressed in all immature gonads of 20 dpf-old zebrafish. Then, GFP expression increased in early differentiated female at 30 and 35dpf to reach a high GFP intensity in well-differentiated ovaries at 40dpf. On the contrary, males consistently displayed low GFP expression as compared to female whatever their stage of development, resulting in a clear dimorphic expression between both sexes. Interestingly, fish that undergoes ovary-to-testis transition (35 and 40dpf) presented GFP levels similar to males or intermediate between females and males. In this transgenic line our results confirm that cyp19a1a is expressed early during development, before the histological differentiation of the gonads, and that the down-regulation of cyp19a1a expression is likely responsible for the testicular differentiation. Moreover, we show that although cyp19a1a expression exhibits a clear dimorphic expression pattern in gonads during sexual differentiation, its expression persists whatever the sex suggesting that estradiol synthesis is important for gonadal development of both sexes. Monitoring the expression of GFP in control and exposed-fish will help determine the sensitivity of this transgenic line to EDCs and to refine mechanistic based-assays for the study of EDCs. In fine, this transgenic zebrafish line will be a useful tool to study physiological processes such as reproduction and sexual differentiation, and their perturbations by EDCs. Copyright © 2017 Elsevier Inc. All rights reserved.

Proteomic analysis of zebrafish brain tissue following exposure to the pesticide prochloraz

EPA Science Inventory

The hypothalamus-pituitary-gonadal (HPG) axis plays a central role in the maintenance of homeostasis. Disruptions of this axis can have important implications for development and other critical biological processes. A number of compounds found in aquatic environments are known t...

Germ Cells Are Not Required to Establish the Female Pathway in Mouse Fetal Gonads

PubMed Central

Maatouk, Danielle M.; Mork, Lindsey; Hinson, Ashley; Kobayashi, Akio; McMahon, Andrew P.; Capel, Blanche

2012-01-01

The fetal gonad is composed of a mixture of somatic cell lineages and germ cells. The fate of the gonad, male or female, is determined by a population of somatic cells that differentiate into Sertoli or granulosa cells and direct testis or ovary development. It is well established that germ cells are not required for the establishment or maintenance of Sertoli cells or testis cords in the male gonad. However, in the agametic ovary, follicles do not form suggesting that germ cells may influence granulosa cell development. Prior investigations of ovaries in which pre-meiotic germ cells were ablated during fetal life reported no histological changes during stages prior to birth. However, whether granulosa cells underwent normal molecular differentiation was not investigated. In cases where germ cell loss occurred secondary to other mutations, transdifferentiation of granulosa cells towards a Sertoli cell fate was observed, raising questions about whether germ cells play an active role in establishing or maintaining the fate of granulosa cells. We developed a group of molecular markers associated with ovarian development, and show here that the loss of pre-meiotic germ cells does not disrupt the somatic ovarian differentiation program during fetal life, or cause transdifferentiation as defined by expression of Sertoli markers. Since we do not find defects in the ovarian somatic program, the subsequent failure to form follicles at perinatal stages is likely attributable to the absence of germ cells rather than to defects in the somatic cells. PMID:23091613

Effects of global warming on fish reproductive endocrine axis, with special emphasis in pejerrey Odontesthes bonariensis.

PubMed

Miranda, Leandro Andrés; Chalde, Tomás; Elisio, Mariano; Strüssmann, Carlos Augusto

2013-10-01

The ongoing of global warming trend has led to an increase in temperature of several water bodies. Reproduction in fish, compared with other physiological processes, only occurs in a bounded temperature range; therefore, small changes in water temperature could significantly affect this process. This review provides evidence that fish reproduction may be directly affected by further global warming and that abnormal high water temperature impairs the expression of important genes throughout the brain-pituitary-gonad axis. In all fishes studied, gonads seem to be the organ more readily damaged by heat treatments through the inhibition of the gene expression and subsequent synthesis of different gonadal steroidogenic enzymes. In view of the feedback role of sex steroids upon the synthesis and release of GnRH and GtHs in fish, it is possible that the inhibition observed at brain and pituitary levels in treated fish is consequence of the sharp decrease in plasma steroids levels. Results of in vitro studies on the inhibition of pejerrey gonad aromatase expression by high temperature corroborate that ovary functions are directly disrupted by high temperature independently of the brain-pituitary axis. For the reproductive responses obtained in laboratory fish studies, it is plausible to predict changes in the timing and magnitude of reproductive activity or even the total failure of spawning season may occur in warm years, reducing annual reproductive output and affecting future populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Black carp vasa identifies embryonic and gonadal germ cells.

PubMed

Xue, Ting; Yu, Miao; Pan, Qihua; Wang, Yizhou; Fang, Jian; Li, Lingyu; Deng, Yu; Chen, Kai; Wang, Qian; Chen, Tiansheng

2017-07-01

Identification of molecular markers is an essential step in the study of germ cells. Vasa is an RNA helicase and a well-known germ cell marker that plays a crucial role in germ cell development. Here, we identified the Vasa homolog termed Mpvasa as the first germ cell marker in black carp (Mylopharyngodon piceus). First, a 2819-bp full-length Mpvasa complementary DNA (cDNA) was cloned by PCR using degenerated primers of conserved sequences and gene-specific primers. The Mpvasa cDNA sequence encodes a 637-amino acid protein that contains eight conserved characteristic motifs of the DEAD box protein family, and shares high identity to grass carp (81%) and zebrafish (74%) vasa homologs. Second, Mpvasa expression was restricted to the gonad in adulthood by RT-PCR and Western blot analysis. The dynamic patterns of temporal-spatial expression of Mpvasa during gametogenesis were examined by in situ hybridization, and Mpvasa transcripts were strictly detected in gonadal germ cells throughout oogenesis, predominantly in immature oocytes (stage I, II, and III oocytes). Third, Mpvasa transcripts were highly detected in unfertilized eggs and early embryos, and the signal indicated a dynamic migration of the primordial germ cells during embryogenesis, suggesting that Mpvasa transcripts were maternally inherited and specifically distributed in germ cells. Taken together, these results demonstrated that Mpvasa is an applicable molecular marker for identification of gonadal and embryonic germ cells, which facilitates the isolation and utilization of germ cells in black carp.

The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1).

PubMed

Wolfe, Andrew; Divall, Sara; Wu, Sheng

2014-10-01

The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. Copyright © 2014 Elsevier Inc. All rights reserved.

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

2015-11-02

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.

A naturally occurring Lgr4 splice variant encodes a soluble antagonist useful for demonstrating the gonadal roles of Lgr4 in mammals.

PubMed

Hsu, Pei-Jen; Wu, Fang-Ju; Kudo, Masataka; Hsiao, Chih-Lun; Hsueh, Aaron J W; Luo, Ching-Wei

2014-01-01

Leucine-rich repeat containing G protein-coupled receptor 4 (LGR4) promotes the Wnt signaling through interaction with R-spondins or norrin. Using PCR amplification from rat ovarian cDNAs, we identified a naturally occurring Lgr4 splice variant encoding only the ectodomain of Lgr4, which was named Lgr4-ED. Lgr4-ED can be detected as a secreted protein in the extracts from rodent and bovine postnatal gonads, suggesting conservation of Lgr4-ED in mammals. Recombinant Lgr4-ED purified from the conditioned media of transfected 293T cells was found to dose-dependently inhibit the LGR4-mediated Wnt signaling induced by RSPO2 or norrin, suggesting that it is capable of ligand absorption and could have a potential role as an antagonist. Intraperitoneal injection of purified recombinant Lgr4-ED into newborn mice was found to significantly decrease the testicular expression of estrogen receptor alpha and aquaporin 1, which is similar to the phenotype found in Lgr4-null mice. Administration of recombinant Lgr4-ED to superovulated female rats can also decrease the expression of estrogen receptor alpha, aquaporin 1, LH receptor and other key steroidogenic genes as well as bring about the suppression of progesterone production. Thus, these findings suggest that endogenously expressed Lgr4-ED may act as an antagonist molecule and help to fine-tune the R-spondin/norrin-mediated Lgr4-Wnt signaling during gonadal development.

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.

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...

Cell-autonomous sex determination outside of the gonad

PubMed Central

Arnold, Arthur P.; Chen, Xuqi; Link, Jenny C.; Itoh, Yuichiro; Reue, Karen

2013-01-01

The classic model of sex determination in mammals states that the sex of the individual is determined by the type of gonad that develops, which in turn determines the gonadal hormonal milieu that creates sex differences outside of the gonads. However, XX and XY cells are intrinsically different because of the cell-autonomous sex-biasing action of X and Y genes. Recent studies of mice, in which sex chromosome complement is independent of gonadal sex, reveal that sex chromosome complement has strong effects contributing to sex differences in phenotypes such as metabolism. Adult mice with two X chromosomes (relative to mice with one X chromosome) show dramatically greater increases in body weight and adiposity after gonadectomy, irrespective of their gonadal sex. When fed a high fat diet, XX mice develop striking hyperinsulinemia and fatty liver, relative to XY mice. The sex chromosome effects are modulated by the presence of gonadal hormones, indicating an interaction of the sex-biasing effects of gonadal hormones and sex chromosome genes. Other cell-autonomous sex chromosome effects are detected in mice in many phenotypes. Birds (relative to eutherian mammals) are expected to show more widespread cell-autonomous sex determination in non-gonadal tissues, because of ineffective sex chromosome dosage compensation mechanisms. PMID:23361913

Sex Reversal and Analyses of Possible Involvement of Sex Steroids in Scallop Gonadal Development in Newly Established Organ-Culture Systems.

PubMed

Otani, Ayano; Nakajima, Tadaaki; Okumura, Tomomi; Fujii, Shiro; Tomooka, Yasuhiro

2017-04-01

Many molluscs perform sex reversal, and sex hormones may be involved in the process. In adult scallops, Patinopecten yessoensis, gonadotropin releasing hormone and 17β-estradiol (E 2 ) are involved in male sexual maturation, however, little is known about the effects of E 2 and testosterone (T) on the gonadal differentiation in young scallops. In the present study, scallop gonadal development was analyzed to determine the sex reversal stage in Funka bay, and effects of E 2 and T were examined. In Funka bay, almost all scallops were male at month 12. Scallops equipped with ambiguous gonads were 61.1% at month 16 and disappeared at month 18. Therefore, sex reversal in Funka bay occurs at around month 16. For establishment of organ culture systems for bivalves, Manila clam gonads were cultured in 15% L-15 medium diluted with HBSS containing 10% KSR on agarose gel at 10°C, and the gonads survived for 14 days. Scallop gonads were also able to be cultured in 30% L15 medium diluted with ASW containing 10% KSR on agarose gel for seven days. At mature stage, Foxl2 and Tesk were predominantly expressed in ovary and testis, respectively. When scallop gonads at sex reversal stage were organ-cultured, sex steroid treatment decreased Tesk expression in the majority of scallop gonads at sex reversal stage. However, no obvious change in Foxl2 and Tesk expression was detected in mature gonads in response to either E 2 or T in culture, suggesting sex steroid treatment might affect gonadal development at sex reversal stage.

Equine fetal adrenal, gonadal and placental steroidogenesis.

PubMed

Legacki, Erin L; Ball, Barry A; Corbin, C Jo; Loux, Shavahn C; Scoggin, Kirsten E; Stanley, Scott D; Conley, Alan J

2017-10-01

Equine fetuses have substantial circulating pregnenolone concentrations and thus have been postulated to provide significant substrate for placental 5α-reduced pregnane production, but the fetal site of pregnenolone synthesis remains unclear. The current studies investigated steroid concentrations in blood, adrenal glands, gonads and placenta from fetuses (4, 6, 9 and 10 months of gestational age (GA)), as well as tissue steroidogenic enzyme transcript levels. Pregnenolone and dehydroepiandrosterone (DHEA) were the most abundant steroids in fetal blood, pregnenolone was consistently higher but decreased progressively with GA. Tissue steroid concentrations generally paralleled those in serum with time. Adrenal and gonadal tissue pregnenolone concentrations were similar and 100-fold higher than those in allantochorion. DHEA was far higher in gonads than adrenals and progesterone was higher in adrenals than gonads. Androstenedione decreased with GA in adrenals but not in gonads. Transcript analysis generally supported these data. CYP17A1 was higher in fetal gonads than adrenals or allantochorion, and HSD3B1 was higher in fetal adrenals and allantochorion than gonads. CYP11A1 transcript was also significantly higher in adrenals and gonads than allantochorion and CYP19 and SRD5A1 transcripts were higher in allantochorion than either fetal adrenals or gonads. Given these data, and their much greater size, the fetal gonads are the source of DHEA and likely contribute more than fetal adrenal glands to circulating fetal pregnenolone concentrations. Low CYP11A1 but high HSD3B1 and SRD5A1 transcript abundance in allantochorion, and low tissue pregnenolone, suggests that endogenous placental pregnenolone synthesis is low and likely contributes little to equine placental 5α-reduced pregnane secretion. © 2017 Society for Reproduction and Fertility.

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

2017-05-01

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.

A novel morphological approach to gonads in disorders of sex development.

PubMed

Lepais, Laureline; Morel, Yves; Mouriquand, Pierre; Gorduza, Daniela; Plotton, Ingrid; Collardeau-Frachon, Sophie; Dijoud, Frédérique

2016-11-01

Disorders of sex development are defined as congenital conditions with discordance between the phenotype, the genotype, the karyotype, and the hormonal profile. The disorders of sex development consensus classification established in 2005 are mainly based on chromosomal and biological data. However, histological anomalies are not considered. The aims of this study were to define the specific pathological features of gonads in various groups of disorders of sex development in order to clarify the nosology of histological findings and to evaluate the tumor risk in case of a conservative approach. One hundred and seventy-five samples from 86 patients with disorders of sex development were analyzed following a strict histological reading protocol. The term 'gonadal dysgenesis' for the histological analysis was found confusing and therefore excluded. The concept of 'dysplasia' was subsequently introduced in order to describe the architectural disorganization of the gonad (various degrees of irregular seminiferous tubules, thin albuginea, fibrous interstitium). Five histological types were identified: normal gonad, hypoplastic testis, dysplastic testis, streak gonad, and ovotestis. The analysis showed an association between undifferentiated gonadal tissue, a potential precursor of gonadoblastoma, and dysplasia. Dysplasia and undifferentiated gonadal tissue were only encountered in cases of genetic or chromosomal abnormality ('dysgenesis' groups in the disorders of sex development consensus classification). 'Dysgenetic testes', related to an embryonic malformation of the gonad, have variable histological presentations, from normal to streak. Conversely, gonads associated with hormonal deficiencies always display a normal architecture. A loss of expression of AMH and α-inhibin was identified in dysplastic areas. Foci of abnormal expression of the CD117 and OCT4 immature germ cells markers in dysplasia and undifferentiated gonadal tissue were associated with an increased risk of neoplasia. This morphological analysis aims at clarifying the histological classification and gives an indication of tumor risk of gonads in disorders of sex development.

Computational Model of Adrenal Steroidogenesis to Predict Biochemical Response to Endocrine Disruptors

EPA Science Inventory

Steroids, which have an important role in a wide range of physiological processes, are synthesized primarily in the gonads and adrenal glands through a series of enzyme mediated reactions. The activity of steroidogenic enzymes can be altered by various endocrine disrupters (ED), ...

Sex Differences in Rhythmic Preferences in the Budgerigar (Melopsittacus undulatus): A Comparative Study with Humans

PubMed Central

Hoeschele, Marisa; Bowling, Daniel L.

2016-01-01

A variety of parrot species have recently gained attention as members of a small group of non-human animals that are capable of coordinating their movements in time with a rhythmic pulse. This capacity is highly developed in humans, who display unparalleled sensitivity to musical beats and appear to prefer rhythmically organized sounds in their music. Do parrots also exhibit a preference for rhythmic over arrhythmic sounds? Here, we presented humans and budgerigars (Melopsittacus undulatus) – a small parrot species that have been shown to be able to align movements with a beat – with rhythmic and arrhythmic sound patterns in an acoustic place preference paradigm. Both species were allowed to explore an environment for 5 min. We quantified how much time they spent in proximity to rhythmic vs. arrhythmic stimuli. The results show that humans spent more time with rhythmic stimuli, and also preferred rhythmic stimuli when directly asked in a post-test survey. Budgerigars did not show any such overall preferences. However, further examination of the budgerigar results showed an effect of sex, such that male budgerigars spent more time with arrthymic stimuli, and female budgerigars spent more time with rhythmic stimuli. Our results support the idea that rhythmic information is interesting to budgerigars. We suggest that future investigations into the temporal characteristics of naturalistic social behaviors in budgerigars, such as courtship vocalizations and head-bobbing displays, may help explain the sex difference we observed. PMID:27757099

Clinical investigation into feed-related hypervitaminosis D in a captive flock of budgerigars (Melopsittacus undulatus): morbidity, mortalities, and pathologic lesions.

PubMed

Olds, June E; Burrough, Eric; Madison, Darin; Ensley, Steve; Horst, Ronald; Janke, Bruce H; Schwartz, Kent; Stevenson, Gregory W; Gauger, Phillip; Cooper, Vickie L; Arruda, Paulo; Opriessnig, Tanja

2015-03-01

The Blank Park Zoo began suffering mortalities in the spring of 2012 within a flock of 229 captive budgerigars (Melopsittacus undulatus) housed in an interactive public-feeding aviary. Clinical signs in affected birds included weakness, posterior paresis, inability to fly, or acute death. Gross and microscopic lesions were not initially apparent in acutely affected deceased birds. Many birds had evidence of trauma, which is now hypothesized to have been related to the birds' weakness. Investigation into the cause(s) of morbidity and mortality were complicated by the opening of a new interactive enclosure. For this reason, environmental conditions and husbandry protocols were heavily scrutinized. Microscopic examination of dead budgies later in the course of the investigation revealed mineralization of soft tissues consistent with hypervitaminosis D. Pooled serum analysis of deceased birds identified elevated vitamin D3 levels. Vitamin D3 analysis was performed on the feed sticks offered by the public and the formulated maintenance diet fed to the flock. This analysis detected elevated levels of vitamin D3 that were 22.5-times the manufacturer's labeled content in the formulated diet. These findings contributed to a manufacturer recall of more than 100 formulated diets fed to a wide variety of domestic and captive wild animal species throughout the United States and internationally. This case report discusses the complexities of determining the etiology of a toxic event in a zoologic institution.

Temporal coherence for pure tones in budgerigars (Melopsittacus undulatus) and humans (Homo sapiens).

PubMed

Neilans, Erikson G; Dent, Micheal L

2015-02-01

Auditory scene analysis has been suggested as a universal process that exists across all animals. Relative to humans, however, little work has been devoted to how animals perceptually isolate different sound sources. Frequency separation of sounds is arguably the most common parameter studied in auditory streaming, but it is not the only factor contributing to how the auditory scene is perceived. Researchers have found that in humans, even at large frequency separations, synchronous tones are heard as a single auditory stream, whereas asynchronous tones with the same frequency separations are perceived as 2 distinct sounds. These findings demonstrate how both the timing and frequency separation of sounds are important for auditory scene analysis. It is unclear how animals, such as budgerigars (Melopsittacus undulatus), perceive synchronous and asynchronous sounds. In this study, budgerigars and humans (Homo sapiens) were tested on their perception of synchronous, asynchronous, and partially overlapping pure tones using the same psychophysical procedures. Species differences were found between budgerigars and humans in how partially overlapping sounds were perceived, with budgerigars more likely to segregate overlapping sounds and humans more apt to fuse the 2 sounds together. The results also illustrated that temporal cues are particularly important for stream segregation of overlapping sounds. Lastly, budgerigars were found to segregate partially overlapping sounds in a manner predicted by computational models of streaming, whereas humans were not. PsycINFO Database Record (c) 2015 APA, all rights reserved.

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. Copyright © 2016 the American Physiological Society.

Maturity Gonad Sea Cucumber Holothuria scabra Under The Month Cycle

NASA Astrophysics Data System (ADS)

Penina Tua Rahantoknam, Santi

2017-10-01

Gonad maturity level of the sea cucumber Holothuria scabra is important to note for selection of parent ready spawn. Sea cucumbers are giving a reaction to the treatment of excitatory spawn mature individuals only. For the determination of the level of maturity of gonads of sea cucumbers, the necessary observation of the gonads are microscopic, macroscopic and gonad maturity gonado somatic indeks (GSI). GSI value is important to know the changes that occur in the gonads quantitatively, so that time can be presumed spawning (Effendie, 1997). Reproductive cycle can be determined by observing the evolution of GSI. The study of sea cucumbers Holothuria scabra gonad maturity conducted in Langgur, Southeast Maluku. Observations were made at every cycle of the moon is the full moon phase (BP) and new moon (BB) in the period January 29, 2017 until July 23, 2017. Observations H. scabra gonad maturity level is done with surgery, observation and calculation GSI gonad histology. GSI highest value obtained in May that full moon cycle at 90% of individuals that are in the spawning stage (phase 5), then 70% of the individuals that are in the spawning stage (phase 5) in March that the full moon cycle. The results obtained show that the peak spawning H. scabra period January 2017 to July 2017 occurred on the full moon cycle in May.

The pineal gland - Its possible roles in human reproduction

NASA Technical Reports Server (NTRS)

Brzezinski, Amnon; Wurtman, Richard J.

1988-01-01

The paper discusses the role of the pineal gland in controlling mammalian reproduction, with particular attention given to the role of melatonin in polyestrus mammals, like humans and laboratory rodents. Evidence is cited indicating the influence of melatonin production and blood content on the age of puberty, the timing of the ovulatory cycle, gonadal steriodogenesis, and patterns of reproductive behavior. It is suggested that abnormal patterns of melatonin might be associated with amenorrhea, anovulation, unexplained infertility, premature menopause, and habitual abortions.

Dmrt1 is necessary for male sexual development in zebrafish

PubMed Central

Webster, Kaitlyn A.; Schach, Ursula; Ordaz, Angel; Steinfeld, Jocelyn S.; Draper, Bruce W.; Siegfried, Kellee R.

2018-01-01

The dmrt1 (doublesex and mab-3 related transcription factor 1) gene is a key regulator of sex determination and/or gonadal sex differentiation across metazoan animals. This is unusual given that sex determination genes are typically not well conserved. The mechanisms by which zebrafish sex is determined have remained elusive due to the lack of sex chromosomes and the complex polygenic nature of sex determination in domesticated strains. To investigate the role of dmrt1 in zebrafish sex determination and gonad development, we isolated mutations disrupting this gene. We found that the majority of dmrt1 mutant fish develop as fertile females suggesting a complete male-to-female sex reversal in mutant animals that would have otherwise developed as males. A small percentage of mutant animals became males, but were sterile and displayed testicular dysgenesis. Therefore zebrafish dmrt1 functions in male sex determination and testis development. Mutant males had aberrant gonadal development at the onset of gonadal sex-differentiation, displaying reduced oocyte apoptosis followed by development of intersex gonads and failed testis morphogenesis and spermatogenesis. By contrast, female ovaries developed normally. We found that Dmrt1 is necessary for normal transcriptional regulation of the amh (anti-Müllerian hormone) and foxl2 (forkhead box L2) genes, which are thought to be important for male or female sexual development respectively. Interestingly, we identified one dmrt1 mutant allele that cooperates with a linked segregation distorter locus to generate an apparent XY sex determination mechanism. We conclude that dmrt1 is dispensable for ovary development but necessary for testis development in zebrafish, and that dmrt1 promotes male development by transcriptionally regulating male and female genes as has been described in other animals. Furthermore, the strong sex-ratio bias caused by dmrt1 reduction-of-function points to potential mechanisms through which sex chromosomes may evolve. PMID:27940159

Characterization and differential expression of three GnRH forms during reproductive development in cultured turbot Schophthalmus maximus

NASA Astrophysics Data System (ADS)

Zhao, Chunyan; Xu, Shihong; Feng, Chengcheng; Liu, Yifan; Yang, Yang; Wang, Yanfeng; Xiao, Yongshuang; Song, Zongcheng; Liu, Qinghua; Li, Jun

2017-10-01

Turbots (Schophthalmus maximus), one of the most important economic marine flatfish species, fail to undergo final spawning and spermiation naturally under artificial farming conditions. In vertebrates, reproduction is regulated by the brain-pituitary-gonadal axis (BPG-axis), and gonadotropin releasing hormone (GnRH) is one of its key components. Therefore, to better understand the physiology of reproduction in the turbot, three of the genes encoding GnRH subtypes—sbGnRH, cGnRH-II and sGnRH—were cloned and sequenced by isolating the cDNA sequences. The localizations and patterns of expression of their mRNAs were also evaluated during seasonal gonadal development. All three mRNAs were expressed abundantly in the brain; sbGnRH and sGnRH mRNAs were also detected in the gonads and pituitary gland, and sbGnRH expression was much higher than that of sGnRH, indicating the critical role of sbGnRH in regulating the BPG-axis. Moreover, the brain expression patterns of sbGnRH and sGnRH mRNAs showed an increased trend during gonadal development, peaking in mature stages. This indicated the direct regulation of gonadal development by the GnRH system. In addition, cGnRH-II mRNA expression showed no significant variations, suggesting that cGnRH-II is not critically involved in the control of reproduction. Further, the mRNA abundances of the three GnRH forms in the breeding season were significantly higher than those in immature and post-breeding stages in all analyzed brain areas. Therefore, we propose that sbGnRH is the most important hormone for the regulation of reproduction in turbot via the BPG-axis. These results will help in better understanding the reproductive endocrine mechanisms of turbots and lay the groundwork for additional studies aimed at comparing the reproductive physiology of wild individuals with those raised under artificial conditions.

Reproductive endocrinology in chondrichthyans: the present and the future.

PubMed

Awruch, C A

2013-10-01

The class Chondrichthyes, that includes Elasmobranchii and Holocephali, is a diverse group of fish occupying a key position at the base of vertebrate evolution. Their evolutionary success is greatly attributed to their wide range of reproductive strategies controlled by different endocrine mechanics. As in other vertebrates, hormonal control of reproduction in chondrichthyans is mediated by the neuropeptide gonadotropin-releasing hormone (GnRH) that regulates the brain control of gonadal activity via a hypothalamus-pituitary-gonadal (HPG) axis. Chondrichthyans lack of a direct vascular supply from the hypothalamus to the zone of the pituitary where the gonadotropic activity resides, thus transport between these two zones likely occurs via the general circulation. In the brain of elasmobranchs, two groups of GnRH, GnRH-I and GnRH-II were identified, and the presence of two immunoreactive gonadotropins similar to the luteinising (LH) and follicle stimulating (FSH) hormones was identified in the pituitary. In holocephalans, only GnRH-II has been confirmed, and while gonadotropin activity has been found in the buccal pituitary lobe, the presence of gonadotropin receptors in the gonads remains unknowns. The diversity of reproductive strategies display by chondrichthyans makes it difficult to generalize the control of gametogenesis and steroidogenesis; however, some general patterns emerge. In both sexes, androgens and estrogens are the main steroids during gonadal growth; while progestins have maturational activity. Androgens also form the precursors for estrogen steroid production. Estrogens stimulate the hepatic synthesis of yolk and stimulate the development of different part of the reproductive tract in females. The role of other gonadal steroids may play in chondrichthyan reproduction remains largely unknown. Future work should concentrate in filling the gaps into the current knowledge of the HPG axis regulation, and the use of reproductive endocrinology as a non-lethal technique for management of chondrichthyan populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Prenatal endocrine influences on sexual orientation and on sexually differentiated childhood behavior

PubMed Central

Hines, Melissa

2012-01-01

Both sexual orientation and sex-typical childhood behaviors, such as toy, playmate and activity preferences, show substantial sex differences, as well as substantial variability within each sex. In other species, behaviors that show sex differences are typically influenced by exposure to gonadal steroids, particularly testosterone and its metabolites, during early development (prenatally or neonatally). This article reviews the evidence regarding prenatal influences of gonadal steroids on human sexual orientation, as well as sex-typed childhood behaviors that predict subsequent sexual orientation. The evidence supports a role for prenatal testosterone exposure in the development of sex-typed interests in childhood, as well as in sexual orientation in later life, at least for some individuals. It appears, however, that other factors, in addition to hormones, play an important role in determining sexual orientation. These factors have not been well-characterized, but possibilities include direct genetic effects, and effects of maternal factors during pregnancy. Although a role for hormones during early development has been established, it also appears that there may be multiple pathways to a given sexual orientation outcome and some of these pathways may not involve hormones. PMID:21333673

Prenatal endocrine influences on sexual orientation and on sexually differentiated childhood behavior.

PubMed

Hines, Melissa

2011-04-01

Both sexual orientation and sex-typical childhood behaviors, such as toy, playmate and activity preferences, show substantial sex differences, as well as substantial variability within each sex. In other species, behaviors that show sex differences are typically influenced by exposure to gonadal steroids, particularly testosterone and its metabolites, during early development (prenatally or neonatally). This article reviews the evidence regarding prenatal influences of gonadal steroids on human sexual orientation, as well as sex-typed childhood behaviors that predict subsequent sexual orientation. The evidence supports a role for prenatal testosterone exposure in the development of sex-typed interests in childhood, as well as in sexual orientation in later life, at least for some individuals. It appears, however, that other factors, in addition to hormones, play an important role in determining sexual orientation. These factors have not been well-characterized, but possibilities include direct genetic effects, and effects of maternal factors during pregnancy. Although a role for hormones during early development has been established, it also appears that there may be multiple pathways to a given sexual orientation outcome and some of these pathways may not involve hormones. Copyright © 2011 Elsevier Inc. All rights reserved.

Sex Change in Clownfish: Molecular Insights from Transcriptome Analysis.

PubMed

Casas, Laura; Saborido-Rey, Fran; Ryu, Taewoo; Michell, Craig; Ravasi, Timothy; Irigoien, Xabier

2016-10-17

Sequential hermaphroditism is a unique reproductive strategy among teleosts that is displayed mainly in fish species living in the coral reef environment. The reproductive biology of hermaphrodites has long been intriguing; however, very little is known about the molecular pathways underlying their sex change. Here, we provide the first de novo transcriptome analyses of a hermaphrodite teleost´s undergoing sex change in its natural environment. Our study has examined relative gene expression across multiple groups-rather than just two contrasting conditions- and has allowed us to explore the differential expression patterns throughout the whole process. Our analysis has highlighted the rapid and complex genomic response of the brain associated with sex change, which is subsequently transmitted to the gonads, identifying a large number of candidate genes, some well-known and some novel, involved in the process. The present study provides strong evidence of the importance of the sex steroidogenic machinery during sex change in clownfish, with the aromatase gene playing a central role, both in the brain and the gonad. This work constitutes the first genome-wide study in a social sex-changing species and provides insights into the genetic mechanism governing social sex change and gonadal restructuring in protandrous hermaphrodites.

Androgen induces gonadal soma-derived factor, Gsdf, in XX gonads correlated to sex-reversal but not Dmrt1 directly, in the teleost fish, northern medaka (Oryzias sakaizumii).

PubMed

Horie, Yoshifumi; Myosho, Taijun; Sato, Tadashi; Sakaizumi, Mitsuru; Hamaguchi, Satoshi; Kobayashi, Tohru

2016-11-15

In the inbred HNI-II strain of Oryzias sakaizumii, Dmy and Gsdf are expressed in XY gonads from Stages 35 and 36, respectively, similarly to the inbred Hd-rR strain of Oryzias latipes. However, Dmrt1 respectively becomes detectable at Stage 36 and 5 days post hatching (dph) in the two strains. In XX HNI-II embryos, 17α-methyltestosterone (MT) induces Gsdf mRNA from Stage 36, accompanied by complete sex-reversal in all treated individuals (MT, 10 ng/mL), while Dmrt1 mRNA was first detectable at 5 dph. In XX d-rR, MT induced Gsdf mRNA expression and sex-reversal in only some of the treated individuals. Together, these results suggest the testis differentiation cascade in XY individuals differs between the HNI-II and Hd-rR strains. In addition, it is suggested that androgen-induced XX sex-reversal proceeds via an androgen-Gsdf-Dmrt1 cascade and that Gsdf plays an important role in sex-reversal in medaka. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Sex Change in Clownfish: Molecular Insights from Transcriptome Analysis

PubMed Central

Casas, Laura; Saborido-Rey, Fran; Ryu, Taewoo; Michell, Craig; Ravasi, Timothy; Irigoien, Xabier

2016-01-01

Sequential hermaphroditism is a unique reproductive strategy among teleosts that is displayed mainly in fish species living in the coral reef environment. The reproductive biology of hermaphrodites has long been intriguing; however, very little is known about the molecular pathways underlying their sex change. Here, we provide the first de novo transcriptome analyses of a hermaphrodite teleost´s undergoing sex change in its natural environment. Our study has examined relative gene expression across multiple groups—rather than just two contrasting conditions— and has allowed us to explore the differential expression patterns throughout the whole process. Our analysis has highlighted the rapid and complex genomic response of the brain associated with sex change, which is subsequently transmitted to the gonads, identifying a large number of candidate genes, some well-known and some novel, involved in the process. The present study provides strong evidence of the importance of the sex steroidogenic machinery during sex change in clownfish, with the aromatase gene playing a central role, both in the brain and the gonad. This work constitutes the first genome-wide study in a social sex-changing species and provides insights into the genetic mechanism governing social sex change and gonadal restructuring in protandrous hermaphrodites. PMID:27748421

EDC testing in the future: Exploring roles of pathway-based in silico, in vitro and in vivo methods

EPA Science Inventory

Many thoroughly validated, robust tests with both mammalian and non-mammalian models have been developed to identify chemicals with the potential to impact endocrine pathways associated with the hypothalamic-pituitary-gonadal (HPG) and thyroidal axes. In the US, for example, the...

Detection of Y chromosome sequences in a 45,X/46,XXq - patient by Southern blot analysis of PCR-amplified DNA and fluorescent in situ hybridization (FISH)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kocova, M.; Siegel, S.F.; Wenger, S.L.

1995-02-13

In some cases of gonadal dysgenesis, cytogenetic analysis seems to be discordant with the phenotype of the patients. We have applied techniques such as Southern blot analysis and fluorescent in situ hybridization (FISH) to resolve the phenotype/genotype discrepancy in a patient with ambiguous genitalia in whom the peripheral blood karotype was 45,X. Gonadectomy at age 7 months showed the gonadal tissue to be prepubertal testis on the left side and a streak gonad on the right. The karyotype obtained from the left gonad was 45,X/46,XXq- and that from the right gonad was 45,X. Three different techniques, PCR amplification, FISH, andmore » chromosome painting for X and Y chromosomes, confirmed the presence of Y chromosome sequences. Five different tissues were evaluated. The highest percentage of Y chromosome positive cells were detected in the left gonad, followed by the peripheral blood lymphocytes, skin fibroblasts, and buccal mucosa. No Y chromosomal material could be identified in the right gonad. Since the Xq- chromosome is present in the left gonad (testis), it is likely that the Xq- contains Y chromosomal material. Sophisticated analysis in this patient showed that she has at least 2 cell lines, one of which contains Y chromosomal material. These techniques elucidated the molecular basis of the genital ambiguity for this patient. When Y chromosome sequences are present in patients with Ullrich-Turner syndrome or gonadal dysgenesis, the risk for gonadal malignancy is significantly increased. Hence, molecular diagnostic methods to ascertain for the presence of Y chromosome sequences may expedite the evaluation of patients with the ambiguous genitalia. 21 refs., 4 figs., 2 tabs.« less

Stress and aversive learning in a wild vertebrate: the role of corticosterone in mediating escape from a novel stressor.

PubMed

Thaker, Maria; Vanak, Abi T; Lima, Steven L; Hews, Diana K

2010-01-01

Elevated plasma corticosterone during stressful events is linked to rapid changes in behavior in vertebrates and can mediate learning and memory consolidation. We tested the importance of acute corticosterone elevation in aversive learning of a novel stressor by wild male eastern fence lizards (Sceloporus undulatus). We found that inhibiting corticosterone elevation (using metyrapone, a corticosterone synthesis blocker) during an encounter with a novel attacker impaired immediate escape responses and limited learning and recall during future encounters. In the wild and in outdoor enclosures, lizards whose acute corticosterone response was blocked by an earlier metyrapone injection did not alter their escape behavior during repeated encounters with the attacker. Control-injected (unblocked) lizards, however, progressively increased flight initiation distance and decreased hiding duration during subsequent encounters. Aversive responses were also initially higher for control lizards exposed to a higher intensity first attack. Further, we demonstrate a role of corticosterone elevation in recollection, since unblocked lizards had heightened antipredator responses 24-28 h later. Exogenously restoring corticosterone levels in metyrapone-injected lizards maintained aversive behaviors and learning at control (unblocked) levels. We suggest that the corticosterone mediation of antipredator behaviors and aversive learning is a critical and general mechanism for the behavioral flexibility of vertebrate prey.

Putting the brakes on reproduction: Implications for conservation, global climate change and biomedicine.

PubMed

Wingfield, John C; Perfito, Nicole; Calisi, Rebecca; Bentley, George; Ubuka, T; Mukai, M; O'Brien, Sara; Tsutsui, K

2016-02-01

Seasonal breeding is widespread in vertebrates and involves sequential development of the gonads, onset of breeding activities (e.g. cycling in females) and then termination resulting in regression of the reproductive system. Whereas males generally show complete spermatogenesis prior to and after onset of breeding, females of many vertebrate species show only partial ovarian development and may delay onset of cycling (e.g. estrous), yolk deposition or germinal vesicle breakdown until conditions conducive for ovulation and onset of breeding are favorable. Regulation of this "brake" on the onset of breeding remains relatively unknown, but could have profound implications for conservation efforts and for "mismatches" of breeding in relation to global climate change. Using avian models it is proposed that a brain peptide, gonadotropin-inhibitory hormone (GnIH), may be the brake to prevent onset of breeding in females. Evidence to date suggests that although GnIH may be involved in the regulation of gonadal development and regression, it plays more regulatory roles in the process of final ovarian development leading to ovulation, transitions from sexual to parental behavior and suppression of reproductive function by environmental stress. Accumulating experimental evidence strongly suggests that GnIH inhibits actions of gonadotropin-releasing hormones on behavior (central effects), gonadotropin secretion (central and hypophysiotropic effects), and has direct actions in the gonad to inhibit steroidogenesis. Thus, actual onset of breeding activities leading to ovulation may involve environmental cues releasing an inhibition (brake) on the hypothalamo-pituitary-gonad axis. Copyright © 2015 Elsevier Inc. All rights reserved.

CLONING AND EXPRESSION OF THE TRANSLOCATOR PROTEIN (18 KDA), VOLTAGE-DEPENDENT ANION CHANNEL, AND DIAZEPAM BINDING INHIBITOR IN THE GONAD OF LARGEMOUTH BASS (MICROPTERUS SALMOIDES) ACROSS THE REPRODUCTIVE CYCLE

PubMed Central

Doperalski, Nicholas J.; Martyniuk, Christopher J.; Prucha, Melinda S.; Kroll, Kevin J.; Denslow, Nancy D.; Barber, David S.

2011-01-01

Cholesterol transport across the mitochondrial membrane is rate-limiting for steroidogenesis in vertebrates. Previous studies in fish have characterized expression of the steroidogenic acute regulatory protein, however the function and regulation of other genes and proteins involved in piscine cholesterol transport have not been evaluated. In the current study, mRNA sequences of the 18 kDa translocator protein (tspo; formerly peripheral benzodiazepine receptor), voltage-dependent anion channel (vdac), and diazepam binding inhibitor (dbi; also acyl-CoA binding protein) were cloned from largemouth bass. Gonadal expression was examined across reproductive stages to determine if expression is correlated with changes in steroid levels and with indicators of reproductive maturation. In testis, transcript abundance of tspo and dbi increased with reproductive maturation (6- and 23-fold maximal increase, respectively) and expression of tspo and dbi was positively correlated with reproductive stage, gonadosomatic index (GSI), and circulating levels of testosterone. Testis vdac expression was positively correlated with reproductive stage and GSI. In females, gonadal tspo and vdac expression was negatively correlated with GSI and levels of plasma testosterone and 17β-estradiol. Ovarian dbi expression was not correlated with indicators of reproductive maturation. These studies represent the first investigation of the steroidogenic role of tspo, vdac, and dbi in fish. Findings suggest that cholesterol transport in largemouth bass testis, but not ovary, may be transcriptionally-regulated, however further investigation will be necessary to fully elucidate the role of these genes in largemouth bass steroidogenesis. PMID:21600210

Two Classes of Gap Junction Channels Mediate Soma-Germline Interactions Essential for Germline Proliferation and Gametogenesis in Caenorhabditis elegans

PubMed Central

Starich, Todd A.; Hall, David H.; Greenstein, David

2014-01-01

In all animals examined, somatic cells of the gonad control multiple biological processes essential for germline development. Gap junction channels, composed of connexins in vertebrates and innexins in invertebrates, permit direct intercellular communication between cells and frequently form between somatic gonadal cells and germ cells. Gap junctions comprise hexameric hemichannels in apposing cells that dock to form channels for the exchange of small molecules. Here we report essential roles for two classes of gap junction channels, composed of five innexin proteins, in supporting the proliferation of germline stem cells and gametogenesis in the nematode Caenorhabditis elegans. Transmission electron microscopy of freeze-fracture replicas and fluorescence microscopy show that gap junctions between somatic cells and germ cells are more extensive than previously appreciated and are found throughout the gonad. One class of gap junctions, composed of INX-8 and INX-9 in the soma and INX-14 and INX-21 in the germ line, is required for the proliferation and differentiation of germline stem cells. Genetic epistasis experiments establish a role for these gap junction channels in germline proliferation independent of the glp-1/Notch pathway. A second class of gap junctions, composed of somatic INX-8 and INX-9 and germline INX-14 and INX-22, is required for the negative regulation of oocyte meiotic maturation. Rescue of gap junction channel formation in the stem cell niche rescues germline proliferation and uncovers a later channel requirement for embryonic viability. This analysis reveals gap junctions as a central organizing feature of many soma–germline interactions in C. elegans. PMID:25195067

Overactive type 2 cannabinoid receptor induces meiosis in fetal gonads and impairs ovarian reserve.

PubMed

De Domenico, Emanuela; Todaro, Federica; Rossi, Gabriele; Dolci, Susanna; Geremia, Raffaele; Rossi, Pellegrino; Grimaldi, Paola

2017-10-05

Type 2 cannabinoid receptor (CB 2 R) has been proposed to promote in vitro meiotic entry of postnatal male germ cells and to maintain the temporal progression of spermatogenesis in vivo. However, no information is presently available on the role played by CB 2 R in male and female fetal gonads. Here we show that in vitro pharmacological stimulation with JWH133, a CB 2 R agonist, induced activation of the meiotic program in both male and female fetal gonads. Upon stimulation, gonocytes initiated the meiotic program but became arrested at early stages of prophase I, while oocytes showed an increased rate of meiotic entry and progression toward more advanced stage of meiosis. Acceleration of meiosis in oocytes was accompanied by a strong increase in the percentage of γ-H2AX-positive pachytene and diplotene cells, paralleled by an increase of TUNEL-positive cells, suggesting that DNA double-strand breaks were not correctly repaired during meiosis, leading to oocyte apoptosis. Interestingly, in vivo pharmacological stimulation of CB 2 R in fetal germ cells through JWH133 administration to pregnant females caused a significant reduction of primordial and primary follicles in the ovaries of newborns with a consequent depletion of ovarian reserve and reduced fertility in adult life, while no alterations of spermatogenesis in the testis of the offspring were detected. Altogether our findings highlight a pro-meiotic role of CB 2 R in male and female germ cells and suggest that the use of cannabis in pregnant female might represent a risk for fertility and reproductive lifespan in female offspring.

The influence of season on the gonad index and biochemical composition of the sea urchin Paracentrotus lividus from the Golf of Tunis.

PubMed

Arafa, Soumaya; Chouaibi, Moncef; Sadok, Saloua; El Abed, Amor

2012-01-01

Seasonal variation in the gonad weight and biochemical composition of the sea urchin Paracentrotus lividus from the Golf of Tunis (Tunisia) were studied between September 2003 and August 2004. The highest gonad indices occurred in March (16.71%). The spawning period occurred between April and July and resulted in a fall in gonad indices to low level (7.12 ± 0.12%). Protein constituted the main component of the gonad, and lipid and carbohydrate were found at appreciable amounts. Consistent with the gonad cycle, sea urchin biochemical components showed clear seasonal variation with a significant decrease during the spawning period. The polyunsaturated fatty acid (PUFA) group was found at high level (40% of the total fatty acids). Of the PUFA group, eicosapentaenoic (C20:5 n - 3) and eicosatetraenoic (C20:4 n - 3) were the most abundant gonadal lipids. The level of PUFA was significantly affected by temperature variation showing an increase during the cold months and a decrease in the hot months.

The Influence of Season on the Gonad Index and Biochemical Composition of the Sea Urchin Paracentrotus lividus from the Golf of Tunis

PubMed Central

Arafa, Soumaya; Chouaibi, Moncef; Sadok, Saloua; El Abed, Amor

2012-01-01

Seasonal variation in the gonad weight and biochemical composition of the sea urchin Paracentrotus lividus from the Golf of Tunis (Tunisia) were studied between September 2003 and August 2004. The highest gonad indices occurred in March (16.71%). The spawning period occurred between April and July and resulted in a fall in gonad indices to low level (7.12 ± 0.12%). Protein constituted the main component of the gonad, and lipid and carbohydrate were found at appreciable amounts. Consistent with the gonad cycle, sea urchin biochemical components showed clear seasonal variation with a significant decrease during the spawning period. The polyunsaturated fatty acid (PUFA) group was found at high level (40% of the total fatty acids). Of the PUFA group, eicosapentaenoic (C20:5 n − 3) and eicosatetraenoic (C20:4 n − 3) were the most abundant gonadal lipids. The level of PUFA was significantly affected by temperature variation showing an increase during the cold months and a decrease in the hot months. PMID:22629206

Multigeneration Inheritance through Fertile XX Carriers of an NR0B1 (DAX1) Locus Duplication in a Kindred of Females with Isolated XY Gonadal Dysgenesis

PubMed Central

Barbaro, Michela; Cook, Jackie; Lagerstedt-Robinson, Kristina; Wedell, Anna

2012-01-01

A 160 kb minimal common region in Xp21 has been determined as the cause of XY gonadal dysgenesis, if duplicated. The region contains the MAGEB genes and the NR0B1 gene; this is the candidate for gonadal dysgenesis if overexpressed. Most patients present gonadal dysgenesis within a more complex phenotype. However, few independent cases have recently been described presenting with isolated XY gonadal dysgenesis caused by relatively small NR0B1 locus duplications. We have identified another NR0B1 duplication in two sisters with isolated XY gonadal dysgenesis with an X-linked inheritance pattern. We performed X-inactivation studies in three fertile female carriers of three different small NR0B1 locus duplications identified by our group. The carrier mothers did not show obvious skewing of X-chromosome inactivation, suggesting that NR0B1 overexpression does not impair ovarian function. We furthermore emphasize the importance to investigate the NR0B1 locus also in patients with isolated XY gonadal dysgenesis. PMID:22518125

Computational Steroidogenesis Model To Predict Biochemical Responses to Endocrine Active Chemicals: Model Development and Cross Validation

EPA Science Inventory

Steroids, which have an important role in a wide range of physiological processes, are synthesized primarily in the gonads and adrenal glands through a series of enzyme-mediated reactions. The activity of steroidogenic enzymes can be altered by a variety of endocrine active chem...

X-Chromosome Dosage and the Response to Cerebral Ischemia

PubMed Central

Turtzo, L. Christine; Siegel, Chad; McCullough, Louise D.

2011-01-01

Gonadal hormones contribute to ischemic neuroprotection, but cannot fully explain the observed sexual dimorphism in stroke outcomes seen during life stages with low sex steroid hormones. Sex chromosomal complement (XX in females; XY in males) may also contribute to ischemic sexual dimorphism. A transient middle cerebral artery occlusion model was used to investigate the role of X chromosome dosage in female XX and XO littermates of two mouse strains (Paf and EdaTa). Cohorts of XX and XO gonadally intact, ovariectomized, and ovariectomized females supplemented with estrogen were examined. Infarct sizes were equivalent between ovariectomized XX and XO mice, between intact XX and XO mice, and between estrogen-supplemented ovariectomized XX and XO mice. This is the first study to investigate the role of sex chromosome dosage in the response to cerebral ischemia. Neither the number of X chromosomes, nor the parent of origin of the remaining X chromosome, had a significant effect on the degree of cerebral infarction after experimental stroke in adult female mice. Estrogen was protective against cerebral ischemia in both XX and XO mice. PMID:21917808

X chromosome dosage and the response to cerebral ischemia.

PubMed

Turtzo, L Christine; Siegel, Chad; McCullough, Louise D

2011-09-14

Gonadal hormones contribute to ischemic neuroprotection, but cannot fully explain the observed sexual dimorphism in stroke outcomes seen during life stages with low sex steroid hormones. Sex chromosomal complement (XX in females; XY in males) may also contribute to ischemic sexual dimorphism. A transient middle cerebral artery occlusion model was used to investigate the role of X chromosome dosage in female XX and XO littermates of two mouse strains (Paf and Eda(Ta)). Cohorts of XX and XO gonadally intact, ovariectomized, and ovariectomized females supplemented with estrogen were examined. Infarct sizes were equivalent between ovariectomized XX and XO mice, between intact XX and XO mice, and between estrogen-supplemented ovariectomized XX and XO mice. This is the first study to investigate the role of sex chromosome dosage in the response to cerebral ischemia. Neither the number of X chromosomes nor the parent of origin of the remaining X chromosome had a significant effect on the degree of cerebral infarction after experimental stroke in adult female mice. Estrogen was protective against cerebral ischemia in both XX and XO mice.

The end of gonad-centric sex determination in mammals

PubMed Central

Arnold, Arthur P.

2011-01-01

The 20th century theory of mammalian sex determination states that the embryo is sexually indifferent until the differentiation of gonads, after which sex differences in phenotype are caused by differential effects of gonadal hormones. That theory is inadequate because some sex differences precede differentiation of the gonads and/or are determined by non-gonadal effects of the sexual inequality in number and type of sex chromosomes. A general theory of sex determination is proposed, which recognizes multiple parallel primary sex-determining pathways initiated by genes or factors encoded by the sex chromosomes. The separate sex-specific pathways interact to synergize with or antagonize each other, enhancing or reducing sex differences in phenotype. PMID:22078126

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.

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

Prostaglandin D2 Regulates SOX9 Nuclear Translocation during Gonadal Sex Determination in Tammar Wallaby, Macropus eugenii.

PubMed

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

2017-01-01

Sex determination and sexual differentiation pathways are highly conserved between marsupials and eutherians. There are 2 different pathways of prostaglandin D2 (PGD2) synthesis: prostaglandin D synthase (PTGDS) and haematopoietic prostaglandin D synthase (HPGDS). PGD2 regulates the subcellular localization of SOX9 during gonadal sexual differentiation. To investigate the function of PGD2 in the tammar gonad, we cultured undifferentiated male gonads in the presence of the HPGDS inhibitor HQL-79 and female gonads with exogenous PGD2 to mimic activation of the PTGDS-PGD2 pathway. Tammar PTGDS and HPGDS have only 50% similarity with mouse and human orthologues, but functional domains are conserved. The expression of SOX9 was unchanged by the treatments in cultured gonads, but its subcellular localization was markedly affected. SOX9 remained cytoplasmic in the Sertoli cells of testes treated with HQL-79. Treated testes developed a thickened ovary-like surface epithelium. In contrast, SOX9 became nuclear in the granulosa cells of developing ovaries treated with PGD2 and the surface epithelium was thin, as in testes. These results demonstrate that PGD2 regulates the subcellular localization of SOX9 and subsequent gonadal development in the developing marsupial gonads, as it does in mice, and that it must have been an ancestral mechanism. © 2017 S. Karger AG, Basel.

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.

Laparoscopic Removal of Streak Gonads in Turner Syndrome.

PubMed

Mandelberger, Adrienne; Mathews, Shyama; Andikyan, Vaagn; Chuang, Linus

To demonstrate the skills necessary for complete resection of bilateral streak gonads in Turner syndrome. Video case presentation with narration highlighting the key techniques used. The video was deemed exempt from formal review by our institutional review board. Turner syndrome is a form of gonadal dysgenesis that affects 1 in 2500 live births. Patients often have streak gonads and may present with primary amenorrhea or premature ovarian failure. Patients with a mosaic karyotype that includes a Y chromosome are at increased risk for gonadoblastoma and subsequent transformation into malignancy. Gonadectomy is recommended for these patients, typically at adolescence. Streak gonads can be difficult to identify, and tissue margins are often in close proximity to critical retroperitoneal structures. Resection can be technically challenging and requires a thorough understanding of retroperitoneal anatomy and precise dissection techniques to ensure complete removal. Laparoscopic approach to bilateral salpingo-oophorectomy of streak gonads. Retroperitoneal dissection and ureterolysis are performed, with the aid of the Ethicon Harmonic Ace, to ensure complete gonadectomy. Careful and complete resection of gonadal tissue in the hands of a skilled laparoscopic surgeon is key for effective cancer risk reduction surgery in Turner syndrome mosaics. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

Identification, expression analysis, and the regulating function on C/EBPs of KLF10 in Dalian purple sea urchin, Strongylocentrotus nudus.

PubMed

Wu, Kaikai; Jia, Zhiying; Wang, Qi'ai; Wei, Zhenlin; Zhou, Zunchun; Liu, Xiaolin

2017-10-01

Accumulating evidence indicates that Krüppel-like factors (KLFs) play important roles in fat biology via the regulation of CCAAT/enhancer binding proteins (C/EBPs). However, KLFs and C/EBPs have not been identified from Strongylocentrotus nudus, and their roles in this species are not clear. In this study, the full-length cDNA of S. nudus KLF10 (SnKLF10) and three cDNA fragments of S. nudus C/EBPs (SnC/EBPs) were obtained. Examination of tissue distribution and expression patterns during gonadal development implied that SnKLF10 and SnC/EBPs play important roles in gonadal lipogenesis. The presence of transcription factor-binding sites (TFBSs) for KLFs in SnC/EBPs, and the results of an over-expression assay, revealed that SnKLF10 negatively regulates the transcription of SnC/EBPs. In addition, the core promoter regions of SnC/EBPs were determined, and multiple TFBSs for transcription factor (TFs) were identified, which are potential regulators of SnC/EBP transcription. Taken together, these results suggest that SnC/EBP genes are potential targets of SnKLF10, and that SnKLF10 plays a role in lipogenesis by repressing the transcription of SnC/EBPs. These findings provide information for further studies of KLF10 in invertebrates and provide new insight into the regulatory mechanisms of C/EBP transcription.

WNT4 signaling in female gonadal development.

PubMed

Pellegrino, Miriam; Maiorino, Raffaella; Schonauer, Sergio

2010-06-01

WNT4 signaling pathways represent an important step in the multi-faceted process of mammalian gonadal differentiation and the development of internal genitalia. WNT4 protein controls the cytoplasmatic stability of specific transcriptional coactivator beta catenin during both embriogenesis and adult homeostasis. The biological significance of WNT4 consists in determining the final female reproductive system, inhibiting Wolff ducts' differentiation, male steroidogenesis and vascular cell migration. An overview of WNT4 cellular mechanisms is given in order to understand its critical role in the genesis of various human diseases such as congenital malformations and gynecological disorders like polycystic ovary syndrome (PCOS). The final discussion focusses on several possible therapeutic uses of Wnt4 both during pregnancy in order to correct the genetic loss of function of the protein and during adulthood in order to normalize fertility in PCOS-affected females planning pregnancy.

Androgens and bone.

PubMed

De Oliveira, D H A; Fighera, T M; Bianchet, L C; Kulak, C A M; Kulak, J

2012-12-01

Testosterone is the major gonadal sex steroid produced by the testes in men. Androgens induce male sexual differentiation before birth and sexual maturation during puberty; in adult men, they maintain the function of the male genital system, including spermatogenesis. Testosterone is also produced in smaller amounts by the ovaries in women. The adrenal glands produce the weaker androgens dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione. Because testosterone can be metabolized to estradiol by the aromatase enzyme, there has been controversy as to which gonadal sex steroid has the greater skeletal effect. In this respect, there is increasing evidence that at least part of the effects of androgens in men can be explained by their aromatization into estrogens. The current evidence suggests that estradiol plays a greater role in maintenance of skeletal health than testosterone, but that androgens also have direct beneficial effects on bone.

GONAD DOSES IN THE X IRRADIATION OF SOME SO-CALLED MILD ILLNESSES (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glauner, R.; Messner, D.; Thelen, P.O.

1958-10-01

Measurements of gonad doses were carried out on men and women using ionization chambers. In women the measurements were made in the vagina. Gonad doses were measured in patients who received x-ray therapy for puerperal mastitis, sweat gland abscesses in the axilla, and furunculi of the face. The conditions of irradiation, as well as the single and total doses, are briefiy discussed. Various means of reducing gonad dose are discussed in detail. (auth)

Gonadal dysgenesis, Turner syndrome with 46,XX,del(18p)3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Telvi, L.; Ion, R.; Bernheim, A.

1994-09-01

The authors report a case of a female infant with gonadal dysgenesis, clinical features of Turner syndrome and a de novo del(18p). The factors controlling gonadal dysgenesis and Turner syndrome are unknown to date. The genes involved could be located not only on X chromosome but also on autosomes. The present case suggests that one of these genes is situated on the short arm of chromosome 18. We conclude that patients with del(18p) syndrome should be evaluated for gonadal dysgenesis.

A test of multiple hypotheses for the function of call sharing in female budgerigars, Melopsittacus undulatus

PubMed Central

Young, Anna M.; Cordier, Breanne; Mundry, Roger; Wright, Timothy F.

2014-01-01

In many social species group, members share acoustically similar calls. Functional hypotheses have been proposed for call sharing, but previous studies have been limited by an inability to distinguish among these hypotheses. We examined the function of vocal sharing in female budgerigars with a two-part experimental design that allowed us to distinguish between two functional hypotheses. The social association hypothesis proposes that shared calls help animals mediate affiliative and aggressive interactions, while the password hypothesis proposes that shared calls allow animals to distinguish group identity and exclude nonmembers. We also tested the labeling hypothesis, a mechanistic explanation which proposes that shared calls are used to address specific individuals within the sender–receiver relationship. We tested the social association hypothesis by creating four–member flocks of unfamiliar female budgerigars (Melopsittacus undulatus) and then monitoring the birds’ calls, social behaviors, and stress levels via fecal glucocorticoid metabolites. We tested the password hypothesis by moving immigrants into established social groups. To test the labeling hypothesis, we conducted additional recording sessions in which individuals were paired with different group members. The social association hypothesis was supported by the development of multiple shared call types in each cage and a correlation between the number of shared call types and the number of aggressive interactions between pairs of birds. We also found support for calls serving as a labeling mechanism using discriminant function analysis with a permutation procedure. Our results did not support the password hypothesis, as there was no difference in stress or directed behaviors between immigrant and control birds. PMID:24860236

Mass and energy budgets of animals: Behavioral and ecological implications: Progress report for period December 1, 1986-July 1987

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, W.P.

1987-08-01

The vacuum gas-analysis system is running and we use doubly labeled water routinely in our research. We have the computer-controlled respirometer system running, and can routinely measure respiratory gases and body temperatures in small, living mammals. Our heat- and mass-balance model calculations of field metabolism and water loss agree exceptionally well with doubly labeled water measurements of the field metabolism and water loss for Sceloporus undulatus in the sandhill country of western Nebraska. We established theoretical links between our biophysical models of individual animals and population dynamics and community models in the literature. Our general, dry, porous-media model works formore » bird feathers as well as fur. Now heat and mass fluxes for any endotherm in any physical environment can be calculated with accuracy knowing only allometry, insulation properties, core or skin temperature and environmental conditions. We developed a general respiratory water-loss model using a coupled molar and heat balance. We developed a general counter-current heat exchange model with a peripheral heat generation and iterative skin temperature solution. We are testing our endotherm model on four species of temperate and tropical birds. We are completing parameter measurements for a test of the ectotherm model on an herbivorous lizard, like the test described above for the carnivorous lizard, Sceloporus undulatus. We have begun lab and field studies of the energetic costs of parasitism and climate on a small endotherm (using tapeworm infection of white-footed mice, Peromyscus leucopus). 8 figs.« less

Quality changes in sea urchin (Strongylocentrotus nudus) during storage in artificial seawater saturated with oxygen, nitrogen and air.

PubMed

Wang, Chao; Xue, Changhu; Xue, Yong; Li, Zhaojie; Lv, Yingchun; Zhang, Hao

2012-01-15

Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days. The sensory acceptability limit was 11-12, 6-7 and 7-8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB-N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g(-1) for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB-N values of about 25 mg 100 g(-1) should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K-values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P > 0.05) for gonads with the three treatments. Gonads with oxygen packaging had lower sensory demerit point (P < 0.05) and TVB-N values (P < 0.05), and higher relative ATP content (P < 0.01) and K-values (P < 0.05), than that with nitrogen or air packaging, with an extended shelf life of 4-5 days during storage in artificial seawater at 5 ± 1 °C. Copyright © 2011 Society of Chemical Industry.

Utility of Ultrasound and Magnetic Resonance Imaging in Patients with Disorders of Sex Development Who Undergo Prophylactic Gonadectomy.

PubMed

Alaniz, V I; Kobernik, E K; Dillman, J; Quint, E H

2016-12-01

To evaluate ultrasonography and magnetic resonance imaging (MRI) in identifying gonads in patients with disorders of sex development (DSD) who undergo prophylactic gonadectomy, and to assess the capacity of preoperative imaging to detect premalignant and malignant transformation. Retrospective cohort at a tertiary referral center of 39 patients with DSD who underwent MRI and/or ultrasonography before prophylactic gonadectomy. None. Identification of gonads on preoperative imaging. Thirty-three patients underwent ultrasonography, which identified 54% (35/65) of gonads and 14 patients had MRI, which identified 41% (11/27) of gonads. There was no significant difference between imaging modalities in the proportion of gonads identified (P = .25). The proportion of pathology-confirmed dysgenetic gonads identified was higher on ultrasound compared with MRI (51% vs 8%; P = .02). There was no difference in the proportion of pathology-confirmed testes identified on ultrasound and MRI (54% vs 71%; P = .33). Eleven out of 39 patients (28%) were diagnosed with a premalignant lesion, and there were no distinguishing characteristics documented on imaging reports to suggest transformation. The only diagnosed malignancy in this series had imaging describing a "normal-sized ovary." Ultrasonography and MRI identified 40%-50% of gonads in patients with DSD who underwent prophylactic gonadectomy, with no significant difference between the 2 modalities. Clinicians should, therefore, consider ultrasonography as a first-line imaging modality. Premalignant lesions were not detected on either imaging modality. The only malignancy was described as a "normal-sized ovary" which should raise concern in a patient with complete gonadal dysgenesis expected to have streak gonads. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Stem Cells, Progenitor Cells, and Lineage Decisions in the Ovary

PubMed Central

Hummitzsch, Katja; Anderson, Richard A.; Wilhelm, Dagmar; Wu, Ji; Telfer, Evelyn E.; Russell, Darryl L.; Robertson, Sarah A.

2015-01-01

Exploring stem cells in the mammalian ovary has unleashed a Pandora's box of new insights and questions. Recent evidence supports the existence of stem cells of a number of the different cell types within the ovary. The evidence for a stem cell model producing mural granulosa cells and cumulus cells is strong, despite a limited number of reports. The recent identification of a precursor granulosa cell, the gonadal ridge epithelial-like cell, is exciting and novel. The identification of female germline (oogonial) stem cells is still very new and is currently limited to just a few species. Their origins and physiological roles, if any, are unknown, and their potential to produce oocytes and contribute to follicle formation in vivo lacks robust evidence. The precursor of thecal cells remains elusive, and more compelling data are needed. Similarly, claims of very small embryonic-like cells are also preliminary. Surface epithelial cells originating from gonadal ridge epithelial-like cells and from the mesonephric epithelium at the hilum of the ovary have also been proposed. Another important issue is the role of the stroma in guiding the formation of the ovary, ovigerous cords, follicles, and surface epithelium. Immune cells may also play key roles in developmental patterning, given their critical roles in corpora lutea formation and regression. Thus, while the cellular biology of the ovary is extremely important for its major endocrine and fertility roles, there is much still to be discovered. This review draws together the current evidence and perspectives on this topic. PMID:25541635

Unexpected diagnosis of stage IIA dysgerminoma in streak gonad in a patient with Swyer syndrome: a case report.

PubMed

Yada-Hashimoto, Namiko; Komura, Hiroko; Nagata, Shigenori; Kubo, Chiaki; Fujita, Masami; Kamiura, Shoji

2018-06-01

Patients with Swyer syndrome, which is also known as 46,XY pure gonadal dysgenesis, are at an increased risk of gonadoblastoma and germ cell tumor. Prophylactic gonadectomy is recommended for these patients. We report a case of stage IIA dysgerminoma arising in a streak gonad in a patient with Swyer syndrome, which was not diagnosable preoperatively and intraoperatively. The patient was primarily amenorrheic and identified as female phenotypically. She underwent gonadectomy at 27 years of age. Preoperative image analysis showed a relatively small uterus without adnexal masses. Laparoscopic findings showed bilateral streak gonads. Postoperatively, histopathological examination revealed that the patient had dysgerminoma in her left streak gonad. Preoperative and intraoperative diagnosis of dysgerminoma in normal size ovaries is thought to be difficult. Although it is rare, considering the occurrence of dysgerminoma in streak gonad with extension to the mesosalpinx, prompt prophylactic gonadectomy is strongly recommended for these patients regardless of the size of the ovaries.

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.

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. (c) 2010 S. Karger AG, Basel.

Cyclic AMP-dependent modification of gonad-selective TAF(II)105 in a human ovarian granulosa cell line.

PubMed

Wu, Yimin; Lu, Yunzhe; Hu, Yanfen; Li, Rong

2005-11-01

In response to gonadotropins, the elevated level of intracellular-cyclic AMP (cAMP) in ovarian granulosa cells triggers an ordered activation of multiple ovarian genes, which in turn promotes various ovarian functions including folliculogenesis and steroidogenesis. Identification and characterization of transcription factors that control ovarian gene expression are pivotal to the understanding of the molecular basis of the tissue-specific gene regulation programs. The recent discovery of the mouse TATA binding protein (TBP)-associated factor 105 (TAF(II)105) as a gonad-selective transcriptional co-activator strongly suggests that general transcription factors such as TFIID may play a key role in regulating tissue-specific gene expression. Here we show that the human TAF(II)105 protein is preferentially expressed in ovarian granulosa cells. We also identified a novel TAF(II)105 mRNA isoform that results from alternative exon inclusion and is predicted to encode a dominant negative mutant of TAF(II)105. Following stimulation by the adenylyl cyclase activator forskolin, TAF(II)105 in granulosa cells undergoes rapid and transient phosphorylation that is dependent upon protein kinase A (PKA). Thus, our work suggests that pre-mRNA processing and post-translational modification represent two important regulatory steps for the gonad-specific functions of human TAF(II)105. Copyright 2005 Wiley-Liss, Inc.

Expression profiles of gonadotropins and their receptors during 17α-methyltestosterone implantation-induced sex change in the orange-spotted grouper (Epinephelus coioides).

PubMed

Hu, Xuesong; Liu, Xiaochun; Zhang, Haifa; Zhang, Yong; Li, Shuisheng; Sang, Qing; Wang, Qian; Luo, Wenna; Liu, Qizhi; Lu, Danqi; Meng, Zining; Lin, Haoran

2011-06-01

It is known that the hypothalamic-pituitary-gonadal axis participates in the sex change of hermaphrodite teleosts, and gonadal steroid hormones mediate this physiological process. The secretion of gonadal steroids is directly regulated by signaling pathways involving gonadotropins (GtHs) and gonadotropin receptors (GtHRs) in teleosts. To gain insight into the involvement of GtH/GtHR systems in the sex change process, cDNAs encoding follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) were firstly isolated from gonads of orange-spotted grouper (Epinephelus coioides), a protogynous hermaphrodite fish. Reverse transcription-PCR (RT-PCR) analysis demonstrated that the expression of the FSHR was confined to the brain, pituitary gland, ovary, and testis, while the LHR was expressed only in the brain, ovary, and testis. Furthermore, the expression profiles of GtH subunits (FSHβ and LHβ) and their receptors were analyzed in parallel with the serum levels of estradiol-17β (E(2) ), testosterone (T), and 11-ketotestosterone (11-KT) during 17α-methyltestosterone (MT)-induced sex change. Quantitative real-time PCR determined that the abundances of FSHβ and FSHR were significantly inhibited after MT treatment for 2 and 4 weeks, but subsequently returned to the control level after 6 weeks. In contrast, the mRNA levels of LHβ and LHR were significantly elevated throughout the sex change process. During MT-induced sex change, serum concentrations of E(2) remained constant while T and 11-KT levels were significantly increased. Taken together, our results suggest that GtH/GtHR systems are involved in MT-induced sex change, and two signaling pathways may have distinct roles in modulating the variations of the corresponding steroid hormones in the orange-spotted grouper. Copyright © 2011 Wiley-Liss, Inc.

Surrogate production of eggs and sperm by intrapapillary transplantation of germ cells in cytoablated adult fish.

PubMed

Majhi, Sullip Kumar; Hattori, Ricardo Shohei; Rahman, Sheikh Mustafizur; Strüssmann, Carlos Augusto

2014-01-01

Germ cell transplantation (GCT) is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae) were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C) and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively). Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6-39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources.

Surrogate Production of Eggs and Sperm by Intrapapillary Transplantation of Germ Cells in Cytoablated Adult Fish

PubMed Central

Majhi, Sullip Kumar; Hattori, Ricardo Shohei; Rahman, Sheikh Mustafizur; Strüssmann, Carlos Augusto

2014-01-01

Germ cell transplantation (GCT) is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae) were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C) and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively). Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6–39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources. PMID:24748387

Prenatal Exposure to Bisphenol A Disrupts Naturally Occurring Bimodal DNA Methylation at Proximal Promoter of fggy, an Obesity-Relevant Gene Encoding a Carbohydrate Kinase, in Gonadal White Adipose Tissues of CD-1 Mice.

PubMed

Taylor, Julia A; Shioda, Keiko; Mitsunaga, Shino; Yawata, Shiomi; Angle, Brittany M; Nagel, Susan C; Vom Saal, Frederick S; Shioda, Toshi

2018-02-01

Exposure of mammalian fetuses to endocrine disruptors can increase the risk of adult-onset diseases. We previously showed that exposure of mouse fetuses to bisphenol A (BPA) caused adult-onset obesity. To examine roles of epigenetic changes in this delayed toxicity, we determined the effects of fetal mouse exposure to BPA on genome-wide DNA methylation and messenger RNA (mRNA) expression in gonadal white adipose tissues (WATs) by deep sequencing, bisulfite pyrosequencing, and real-time quantitative polymerase chain reaction. Pregnant CD-1 mice (F0) were dosed daily with 0, 5, or 500 μg/kg/d BPA during gestational days 9 to 18, and the weaned F1 animals were fed ad libitum with standard chow until they were euthanized at 19 weeks old. In the vehicle-exposed F1 animals, fggy promoter showed a clear bimodal pattern of very strong (55% to 95%) or very weak (5% to 30%) DNA methylation occurring at nearly equal incidence with no intermediate strength. Promoter hypermethylation completely suppressed mRNA expression. BPA exposure eliminated this naturally occurring dichotomy, shifting fggy promoter toward the hypomethylation state to release transcriptional suppression. The strength of Fggy mRNA expression significantly correlated with increased whole body weight and gonadal fat weight of males but not females. Bioinformatics studies showed that expression of Fggy mRNA is stronger in mouse WATs than in brown adipose tissues and enhanced in gonadal fat by diet-induced obesity. These observations suggest that prenatal exposure to BPA may disrupt the physiological bimodal nature of epigenetic regulation of fggy in mouse WATs, possibly contributing to the adult-onset obesity phenotype. Copyright © 2018 Endocrine Society.

An XRCC4 Splice Mutation Associated With Severe Short Stature, Gonadal Failure, and Early-Onset Metabolic Syndrome

PubMed Central

de Bruin, Christiaan; Mericq, Verónica; Andrew, Shayne F.; van Duyvenvoorde, Hermine A.; Verkaik, Nicole S.; Losekoot, Monique; Porollo, Aleksey; Garcia, Hernán; Kuang, Yi; Hanson, Dan; Clayton, Peter; van Gent, Dik C.; Wit, Jan M.; Hwa, Vivian

2015-01-01

Context: Severe short stature can be caused by defects in numerous biological processes including defects in IGF-1 signaling, centromere function, cell cycle control, and DNA damage repair. Many syndromic causes of short stature are associated with medical comorbidities including hypogonadism and microcephaly. Objective: To identify an underlying genetic etiology in two siblings with severe short stature and gonadal failure. Design: Clinical phenotyping, genetic analysis, complemented by in vitro functional studies of the candidate gene. Setting: An academic pediatric endocrinology clinic. Patients or Other Participants: Two adult siblings (male patient [P1] and female patient 2 [P2]) presented with a history of severe postnatal growth failure (adult heights: P1, −6.8 SD score; P2, −4 SD score), microcephaly, primary gonadal failure, and early-onset metabolic syndrome in late adolescence. In addition, P2 developed a malignant gastrointestinal stromal tumor at age 28. Intervention(s): Single nucleotide polymorphism microarray and exome sequencing. Results: Combined microarray analysis and whole exome sequencing of the two affected siblings and one unaffected sister identified a homozygous variant in XRCC4 as the probable candidate variant. Sanger sequencing and mRNA studies revealed a splice variant resulting in an in-frame deletion of 23 amino acids. Primary fibroblasts (P1) showed a DNA damage repair defect. Conclusions: In this study we have identified a novel pathogenic variant in XRCC4, a gene that plays a critical role in non-homologous end-joining DNA repair. This finding expands the spectrum of DNA damage repair syndromes to include XRCC4 deficiency causing severe postnatal growth failure, microcephaly, gonadal failure, metabolic syndrome, and possibly tumor predisposition. PMID:25742519

A game of two? Gene expression analysis of brain (cyp19a1b) and gonadal (cyp19a1a) aromatase in females of a Neotropical cichlid fish through the parental care period and removal of the offspring.

PubMed

Ramallo, Martín R; Honji, Renato M; Birba, Agustina; Morandini, Leonel; Varela, María L; Genovese, Griselda; Moreira, Renata G; Somoza, Gustavo M; Pandolfi, Matías

2017-10-01

For many species parental behavior is essential for the survival of the offspring. While the ultimate causes of teleost parental behavior have been widely studied, comparatively little is known about its proximate causes. The aim of this study was to analyze the yet unexplored, potential dual role of brain and gonadal aromatases, the enzymes responsible for the conversion of androgens to estrogens in the brains and gonads of teleosts, respectively, on the different stages of the maternal care period of the biparental cichlid Cichlasoma dimerus, locally known as chanchita. By immunohistochemistry we analyzed the neural distribution of brain aromatase and observed it exclusively within the forebrain, including areas involved in the regulation of parental behavior. We next analyzed the gene expression of brain aromatase in the brain, and gonadal aromatase in the ovary, of female chanchitas through the parental care period. To further characterize the physiological environment associated to maternal care, we also evaluated sex steroid levels (17β-estradiol, testosterone and 11-ketotestoterone) and ovarian follicle percentage. The onset of parental behavior specifically downregulated sex steroids synthesis and the rate of ovarian maturation, as denoted by a more than 10-fold decrease in steroid levels and delayed detection of mature follicles in females with offspring, compared to females which eggs were removed. Gene expression levels of both aromatases were independent of maternal care at the evaluated time points, even though they varied during the parental care period. Copyright © 2017 Elsevier Inc. All rights reserved.

Desert hedgehog is a mammal-specific gene expressed during testicular and ovarian development in a marsupial.

PubMed

O'Hara, William A; Azar, Walid J; Behringer, Richard R; Renfree, Marilyn B; Pask, Andrew J

2011-12-01

Desert hedgehog (DHH) belongs to the hedgehog gene family that act as secreted intercellular signal transducers. DHH is an essential morphogen for normal testicular development and function in both mice and humans but is not present in the avian lineage. Like other hedgehog proteins, DHH signals through the patched (PTCH) receptors 1 and 2. Here we examine the expression and protein distribution of DHH, PTCH1 and PTCH2 in the developing testes of a marsupial mammal (the tammar wallaby) to determine whether DHH signalling is a conserved factor in gonadal development in all therian mammals. DHH, PTCH1 and PTCH2 were present in the marsupial genome and highly conserved with their eutherian orthologues. Phylogenetic analyses indicate that DHH has recently evolved and is a mammal-specific hedgehog orthologue. The marsupial PTCH2 receptor had an additional exon (exon 21a) not annotated in eutherian PTCH2 proteins. Interestingly we found evidence of this exon in humans and show that its translation would result in a truncated protein with functions similar to PTCH1. We also show that DHH expression was not restricted to the testes during gonadal development (as in mice), but was also expressed in the developing ovary. Expression of DHH, PTCH1 and PTCH2 in the adult tammar testis and ovary was consistent with findings in the adult mouse. These data suggest that there is a highly conserved role for DHH signalling in the differentiation and function of the mammalian testis and that DHH may be necessary for marsupial ovarian development. The receptors PTCH1 and PTCH2 are highly conserved mediators of hedgehog signalling in both the developing and adult marsupial gonads. Together these findings indicate DHH is an essential therian mammal-specific morphogen in gonadal development and gametogenesis.

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...

Retinoic acid signaling is dispensable for somatic development and function in the mammalian ovary.

PubMed

Minkina, Anna; Lindeman, Robin E; Gearhart, Micah D; Chassot, Anne-Amandine; Chaboissier, Marie-Christine; Ghyselinck, Norbert B; Bardwell, Vivian J; Zarkower, David

2017-04-15

Retinoic acid (RA) is a potent inducer of cell differentiation and plays an essential role in sex-specific germ cell development in the mammalian gonad. RA is essential for male gametogenesis and hence fertility. However, RA can also disrupt sexual cell fate in somatic cells of the testis, promoting transdifferentiation of male Sertoli cells to female granulosa-like cells when the male sexual regulator Dmrt1 is absent. The feminizing ability of RA in the Dmrt1 mutant somatic testis suggests that RA might normally play a role in somatic cell differentiation or cell fate maintenance in the ovary. To test for this possibility we disrupted RA signaling in somatic cells of the early fetal ovary using three genetic strategies and one pharmaceutical approach. We found that deleting all three RA receptors (RARs) in the XX somatic gonad at the time of sex determination did not significantly affect ovarian differentiation, follicle development, or female fertility. Transcriptome analysis of adult triple mutant ovaries revealed remarkably little effect on gene expression in the absence of somatic RAR function. Likewise, deletion of three RA synthesis enzymes (Aldh1a1-3) at the time of sex determination did not masculinize the ovary. A dominant-negative RAR transgene altered granulosa cell proliferation, likely due to interference with a non-RA signaling pathway, but did not prevent granulosa cell specification and oogenesis or abolish fertility. Finally, culture of fetal XX gonads with an RAR antagonist blocked germ cell meiotic initiation but did not disrupt sex-biased gene expression. We conclude that RA signaling, although crucial in the ovary for meiotic initiation, is not required for granulosa cell specification, differentiation, or reproductive function. Copyright © 2017 Elsevier Inc. All rights reserved.

Two classes of gap junction channels mediate soma-germline interactions essential for germline proliferation and gametogenesis in Caenorhabditis elegans.

PubMed

Starich, Todd A; Hall, David H; Greenstein, David

2014-11-01

In all animals examined, somatic cells of the gonad control multiple biological processes essential for germline development. Gap junction channels, composed of connexins in vertebrates and innexins in invertebrates, permit direct intercellular communication between cells and frequently form between somatic gonadal cells and germ cells. Gap junctions comprise hexameric hemichannels in apposing cells that dock to form channels for the exchange of small molecules. Here we report essential roles for two classes of gap junction channels, composed of five innexin proteins, in supporting the proliferation of germline stem cells and gametogenesis in the nematode Caenorhabditis elegans. Transmission electron microscopy of freeze-fracture replicas and fluorescence microscopy show that gap junctions between somatic cells and germ cells are more extensive than previously appreciated and are found throughout the gonad. One class of gap junctions, composed of INX-8 and INX-9 in the soma and INX-14 and INX-21 in the germ line, is required for the proliferation and differentiation of germline stem cells. Genetic epistasis experiments establish a role for these gap junction channels in germline proliferation independent of the glp-1/Notch pathway. A second class of gap junctions, composed of somatic INX-8 and INX-9 and germline INX-14 and INX-22, is required for the negative regulation of oocyte meiotic maturation. Rescue of gap junction channel formation in the stem cell niche rescues germline proliferation and uncovers a later channel requirement for embryonic viability. This analysis reveals gap junctions as a central organizing feature of many soma-germline interactions in C. elegans. Copyright © 2014 by the Genetics Society of America.

Cloning and expression of the translocator protein (18 kDa), voltage-dependent anion channel, and diazepam binding inhibitor in the gonad of largemouth bass (Micropterus salmoides) across the reproductive cycle.

PubMed

Doperalski, Nicholas J; Martyniuk, Christopher J; Prucha, Melinda S; Kroll, Kevin J; Denslow, Nancy D; Barber, David S

2011-08-01

Cholesterol transport across the mitochondrial membrane is rate-limiting for steroidogenesis in vertebrates. Previous studies in fish have characterized expression of the steroidogenic acute regulatory protein, however the function and regulation of other genes and proteins involved in piscine cholesterol transport have not been evaluated. In the current study, mRNA sequences of the 18 kDa translocator protein (tspo; formerly peripheral benzodiazepine receptor), voltage-dependent anion channel (vdac), and diazepam binding inhibitor (dbi; also acyl-CoA binding protein) were cloned from largemouth bass. Gonadal expression was examined across reproductive stages to determine if expression is correlated with changes in steroid levels and with indicators of reproductive maturation. In testis, transcript abundance of tspo and dbi increased with reproductive maturation (6- and 23-fold maximal increase, respectively) and expression of tspo and dbi was positively correlated with reproductive stage, gonadosomatic index (GSI), and circulating levels of testosterone. Testis vdac expression was positively correlated with reproductive stage and GSI. In females, gonadal tspo and vdac expression was negatively correlated with GSI and levels of plasma testosterone and 17β-estradiol. Ovarian dbi expression was not correlated with indicators of reproductive maturation. These studies represent the first investigation of the steroidogenic role of tspo, vdac, and dbi in fish. Findings suggest that cholesterol transport in largemouth bass testis, but not in ovary, may be transcriptionally-regulated, however further investigation will be necessary to fully elucidate the role of these genes in largemouth bass steroidogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of gonadotropin inhibitory hormone or gonadotropin-releasing hormone on reproduction-related genes in the protandrous cinnamon clownfish, Amphiprion melanopus.

PubMed

Choi, Young Jae; Kim, Na Na; Habibi, Hamid R; Choi, Cheol Young

2016-09-01

Hypothalamic peptide neurohormones such as gonadotropin-releasing hormones (GnRHs) and gonadotropin-inhibitory hormone (GnIH) play pivotal roles in the control of reproduction and gonadal maturation in teleost fish. To study the effects of GnIH on fish reproduction, we investigated the influence of seabream GnRH (sbGnRH) and GnIH (both alone and in combination) on levels of reproductive genes (GnIH, GnIH-receptor [GnIH-R], melatonin receptor [MT3], sbGnRH, and gonadotropic hormones [GTHs]) during different stages of gonadal maturation in male, female, and immature cinnamon clownfish, Amphiprion melanopus. The results showed that the expression levels of GnIH, GnIH-R, and MT3 genes increased after the GnIH injection, but decreased after the sbGnRH injection. In addition, these gene expression levels gradually lowered after GnIH3 and sbGnRH combination treatment, as compared to the MT3 mRNA levels of GnIH treatment alone. However, the expression levels of the HPG (hypothalamus-pituitary-gonad) axis genes (sbGnRH and GTHs) decreased after the GnIH injection, but increased after the sbGnRH injection. In all cinnamon clownfish groups, HPG axis gene mRNA levels gradually decreased after mixed GnIH3 and sbGnRH treatment, compared to GnIH treatment alone. The present study provides novel information on the effects of GnIH and strongly supports the hypothesis that GnIH plays an important role in the negative regulation of the HPG axis in the protandrous cinnamon clownfish. Copyright © 2016 Elsevier Inc. All rights reserved.

Cloning, localization and differential expression of Neuropeptide-Y during early brain development and gonadal recrudescence in the catfish, Clarias gariepinus.

PubMed

Sudhakumari, Cheni-Chery; Anitha, Arumugam; Murugananthkumar, Raju; Tiwari, Dinesh Kumar; Bhasker, Dharavath; Senthilkumaran, Balasubramanian; Dutta-Gupta, Aparna

2017-09-15

Neuropeptide-Y (NPY) has diverse physiological functions which are extensively studied in vertebrates. However, regulatory role of NPY in relation to brain ontogeny and recrudescence with reference to reproduction is less understood in fish. Present report for the first time evaluated the significance of NPY by transient esiRNA silencing and also analyzed its expression during brain development and gonadal recrudescence in the catfish, Clarias gariepinus. As a first step, full-length cDNA of NPY was cloned from adult catfish brain, which shared high homology with its counterparts from other teleosts upon phylogenetic analysis. Tissue distribution revealed dominant expression of NPY in brain and testis. NPY expression increased during brain development wherein the levels were higher in 100 and 150days post hatch females than the respective age-matched males. Seasonal cycle analysis showed high expression of NPY in brain during pre-spawning phase in comparison with other reproductive phases. Localization studies exhibited the presence of NPY, abundantly, in the regions of preoptic area, hypothalamus and pituitary. Transient silencing of NPY-esiRNA directly into the brain significantly decreased NPY expression in both the male and female brain of catfish which further resulted in significant decrease of transcripts of tryptophan hydroxylase 2, catfish gonadotropin-releasing hormone (cfGnRH), tyrosine hydroxylase and 3β-hydroxysteroid dehydrogenase in brain and luteinizing hormone-β/gonadotropin-II (lh-β/GTH-II) in pituitary exhibiting its influence on gonadal axis. In addition, significant decrease of several ovary-related transcripts was observed in NPY-esiRNA silenced female catfish, indicating the plausible role of NPY in ovary through cfGnRH-GTH axis. Copyright © 2017 Elsevier Inc. All rights reserved.

Knockdown of the GnRH-II receptor in the porcine testis impairs the biosynthesis of 10 gonadal steroids

USDA-ARS?s Scientific Manuscript database

The second mammalian GnRH isoform (GnRH-II) and its cognate receptor (GnRHR-II) are poor modulators of gonadotropin secretion in swine. However, both are abundantly produced within the porcine testis suggesting an autocrine/paracrine role. Within the boar testis, GnRHR-II immunolocalizes to the plas...

1994 C. H. McCloy Research Lecture: Does Physical Activity Play a Role in Preventing Osteoporosis?

ERIC Educational Resources Information Center

Drinkwater, Barbara L.

1994-01-01

Review considers problems encountered in relating women's physical activity to increases in bone mass, noting the implications of recommending exercise to help prevent osteoporosis based on that information. Research indicates that for the full benefit of exercise on skeletal health, there must be adequate gonadal hormone levels. (SM)

Integrated analysis of miRNA and mRNA expression profiles in tilapia gonads at an early stage of sex differentiation.

PubMed

Tao, Wenjing; Sun, Lina; Shi, Hongjuan; Cheng, Yunying; Jiang, Dongneng; Fu, Beide; Conte, Matthew A; Gammerdinger, William J; Kocher, Thomas D; Wang, Deshou

2016-05-04

MicroRNAs (miRNAs) represent a second regulatory network that has important effects on gene expression and protein translation during biological process. However, the possible role of miRNAs in the early stages of fish sex differentiation is not well understood. In this study, we carried an integrated analysis of miRNA and mRNA expression profiles to explore their possibly regulatory patterns at the critical stage of sex differentiation in tilapia. We identified 279 pre-miRNA genes in tilapia genome, which were highly conserved in other fish species. Based on small RNA library sequencing, we identified 635 mature miRNAs in tilapia gonads, in which 62 and 49 miRNAs showed higher expression in XX and XY gonads, respectively. The predicted targets of these sex-biased miRNAs (e.g., miR-9, miR-21, miR-30a, miR-96, miR-200b, miR-212 and miR-7977) included genes encoding key enzymes in steroidogenic pathways (Cyp11a1, Hsd3b, Cyp19a1a, Hsd11b) and key molecules involved in vertebrate sex differentiation (Foxl2, Amh, Star1, Sf1, Dmrt1, and Gsdf). These genes also showed sex-biased expression in tilapia gonads at 5 dah. Some miRNAs (e.g., miR-96 and miR-737) targeted multiple genes involved in steroid synthesis, suggesting a complex miRNA regulatory network during early sex differentiation in this fish. The sequence and expression patterns of most miRNAs in tilapia are conserved in fishes, indicating the basic functions of vertebrate miRNAs might share a common evolutionary origin. This comprehensive analysis of miRNA and mRNA at the early stage of molecular sex differentiation in tilapia XX and XY gonads lead to the discovery of differentially expressed miRNAs and their putative targets, which will facilitate studies of the regulatory network of molecular sex determination and differentiation in fishes.

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...

[Gonadal ontogenesis and sex differentiation in the sea bass, Dicentrarchus labrax, under fish-farming conditions].

PubMed

Roblin, C; Bruslé, J

1983-01-01

The histology of the different stages of gonadal development (appearance of PGC, edification of gonad primordium, organization of an undifferentiated gonad, testicular or ovarian development) has been studied in fingerlings and juveniles of sea-bass in fish-culture conditions. Sex differentiation with a caudo-cranial gradient was direct and more in accordance with length than with age. Ovarian and testicular differentiation occurred in fish 11 to 23 months old and from 90 to 187 mm SL. Testis ova were frequently observed.

Gonadal disorder in the thinlip grey mullet (Liza ramada, Risso 1827) as a biomarker of environmental stress in surface waters.

PubMed

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

2015-02-05

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.

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

Seasonal modulation of immunity by melatonin and gonadal steroids in a short day breeder goat Capra hircus.

PubMed

Ghosh, Somenath; Singh, Amaresh K; Haldar, Chandana

2014-11-01

Role of melatonin in regulation of immunity and reproduction has never been studied in detail in goats. The aim of the present study was to explore hormonal regulation of immunity in goats with special reference to melatonin. Plasma of male and female goats (n = 18 per sex per season) was processed for hormonal (estrogen, testostrone, and melatonin) and cytokine (interleukin [IL-2], IL-6, and tumor necrosis factor α) measurements during three seasons, i.e., summer, monsoon, and winter. To assess cell-mediated immune response, percent stimulation ratio of thymocytes was recorded during three seasons. To support and establish the modulation by hormones, Western blot analysis for expressions of melatonin receptors (MT1, MT2), androgen receptor, and estrogen receptor α and estimations of marker enzymes, arylalkylamine N-acetyltransferase for melatonin and 3β-hydroxysteroid dehydrogenase activities for steroidogenesis were performed in thymus. All the hormones and cytokines were estimated by commercial kits. Biochemical, immunologic, and Western blot analyses were done by standardized protocols. We noted a significant increase in estrogen and testosterone levels (P < 0.05) in circulation during monsoon along with melatonin (P < 0.05) presenting a parallel relationship. Expressions of melatonin receptors (MT1 and MT2) in thymus of both the sexes were significantly high (P < 0.01) during winter. Estrogen receptor α expression in female thymus was significantly high during monsoon (P < 0.05). However, androgen receptor showed almost static expression pattern in male thymus during three seasons. Further, both arylalkylamineN-acetyltransferase and 3β-hydroxysteroid dehydrogenase enzyme activities were significantly high (P < 0.05; P < 0.01, respectively) during monsoon. These results suggest that there may be a functional parallelism between gonadal steroids and melatonin as melatonin is progonadotrophic in goats. Cell-mediated immune parameters (percent stimulation ratio of thymocytes) and circulatory levels of cytokines (IL-2, IL-6, and tumor necrosis factor α) were significantly high (P < 0.01) during monsoon. In vitro supplementation of gonadal steroids to T-cell culture suppressed immunity but cosupplementation with melatonin restored it. Further, we may also suggest that reproductive and immune seasonality are maintained by variations in circulatory hormones and local synthesis of melatonin and gonadal steroids. These functional interactions between melatonin and gonadal steroid might be of great importance in regulating the goat immunity by developing some hormonal microcircuit (gonadal steroid and melatonin) in lymphatic organs. Copyright © 2014 Elsevier Inc. All rights reserved.

The Ecology of Stress: linking life-history traits with physiological control mechanisms in free-living guanacos

PubMed Central

Jahn, Graciela A.; Soto-Gamboa, Mauricio; Novaro, Andrés J.; Carmanchahi, Pablo

2016-01-01

Background Providing the context for the evolution of life-history traits, habitat features constrain successful ecological and physiological strategies. In vertebrates, a key response to life’s challenges is the activation of the Stress (HPA) and Gonadal (HPG) axes. Much of the interest in stress ecology is motivated by the desire to understand the physiological mechanisms in which the environment affects fitness. As reported in the literature, several intrinsic and extrinsic factors affect variability in hormone levels. In both social and non-social animals, the frequency and type of interaction with conspecifics, as well as the status in social species, can affect HPA axis activity, resulting in changes in the reproductive success of animals. We predicted that a social environment can affect both guanaco axes by increasing the secretion of testosterone (T) and Glucocorticoid (GCs) in response to individual social interactions and the energetic demands of breeding. Assuming that prolonged elevated levels of GCs over time can be harmful to individuals, it is predicted that the HPA axis suppresses the HPG axis and causes T levels to decrease, as GCs increase. Methods All of the data for individuals were collected by non-invasive methods (fecal samples) to address hormonal activities. This is a novel approach in physiological ecology because feces are easily obtained through non-invasive sampling in animal populations. Results As expected, there was a marked adrenal (p-value = .3.4e−12) and gonadal (p-value = 0.002656) response due to seasonal variation in Lama guanicoe. No significant differences were found in fecal GCs metabolites between males/females*season for the entire study period (p-value = 0.2839). Despite the seasonal activity variation in the hormonal profiles, our results show a positive correlation (p-value = 1.952e−11, COR = 0.50) between the adrenal and gonadal system. The marked endocrine (r2 = 0.806) and gonad (r2 = 0.7231) response due to seasonal variation in male guanaco individuals highlights the individual’s energetic demands according to life-history strategies. This is a remarkable result because no inhibition was found between the axes as theory suggests. Finally, the dataset was used to build a reactive scope model for guanacos. Discussion Guanacos cope with the trade-off between sociability and reproductive benefits and costs, by regulating their GCs and T levels on a seasonal basis, suggesting an adaptive role of both axes to different habitat pressures. The results presented here highlight the functional role of stress and gonad axes on a critical phase of a male mammal’s life—the mating period—when all of the resources are at the disposal of the male and must be used to maximize the chances for reproductive success. PMID:27833807

Gonadal status in long-term male survivors of childhood cancer.

PubMed

Brignardello, E; Felicetti, F; Castiglione, A; Nervo, A; Biasin, E; Ciccone, G; Fagioli, F; Corrias, A

2016-05-01

To evaluate the prevalence of gonadal dysfunction and the associated risk factors in a cohort of male childhood cancer survivors (CCS). Gonadal function was evaluated measuring FSH, LH, inhibin B and total testosterone levels. Patients with total testosterone <3 ng/dl were considered to have hypogonadism. Patients with FSH >10 UI/l and inhibin B <100 pg/ml were considered to have spermatogenesis damage (SD). To assess the impact of risk factors, we estimated crude and adjusted OR performing logistic regression models. One hundred and ninety-nine male CCS were enrolled; the median follow-up time was 14.01 years. SD was diagnosed in 68 patients, 16 CCS had primary hypogonadism, and 13 had central hypogonadism. The prevalence of gonadal dysfunction (SD or primary hypogonadism) was 45 %, similar in the three considered periods of pediatric cancer diagnosis (1985-1989, 1990-1999, >2000). The adjusted risk of gonadal dysfunction was higher in patients treated with radiotherapy (OR = 8.72; 95 % CI 3.94-19.30) and in those exposed to both alkylating and platinum-derived agents (OR = 9.22; 95 % CI 2.17-39.23). Sarcomas were the cancer diagnosis associated with the higher risk of gonadal dysfunction (OR = 3.69; 95 % CI 1.11-12.22). An extremely high rate of gonadal dysfunction was detected in patients who underwent hematopoietic stem cell transplantation and/or total body irradiation. Gonadal dysfunction still remains a significant late effect of anticancer therapies; thus, it is mandatory to inform patients (and parents) about this risk, and semen cryopreservation should be offered to all boys who are able to produce semen.

Genetic and epigenetic effects in sex determination.

PubMed

Gunes, Sezgin Ozgur; Metin Mahmutoglu, Asli; Agarwal, Ashok

2016-12-01

Sex determination is a complex and dynamic process with multiple genetic and environmental causes, in which germ and somatic cells receive various sex-specific features. During the fifth week of fetal life, the bipotential embryonic gonad starts to develop in humans. In the bipotential gonadal tissue, certain cell groups start to differentiate to form the ovaries or testes. Despite considerable efforts and advances in identifying the mechanisms playing a role in sex determination and differentiation, the underlying mechanisms of the exact functions of many genes, gene-gene interactions, and epigenetic modifications that are involved in different stages of this cascade are not completely understood. This review aims at discussing current data on the genetic effects via genes and epigenetic mechanisms that affect the regulation of sex determination. Birth Defects Research (Part C) 108:321-336, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Phenotypic Variation in 46,XX Disorders of Sex Development due to the NR5A1 p.R92W Variant: A Sibling Case Report and Literature Review.

PubMed

Takasawa, Kei; Igarashi, Maki; Ono, Makoto; Takemoto, Akira; Takada, Shuji; Yamataka, Atsuyuki; Ogata, Tsutomu; Morio, Tomohiro; Fukami, Maki; Kashimada, Kenichi

2017-01-01

Recently, a heterozygous missense mutation in NR5A1, p.R92W, was identified as a cause of 46,XX testicular/ovo-testicular disorders of sexual development (DSD). We report a sibling pair with 46,XX DSD due to an NR5A1 mutation with distinct phenotypes, including external and internal genitalia and gonads, for whom different rearing sexes were selected. Thus, the phenotypes of p.R92W vary, even within a family. The father of the patients showed oligozoospermia with the p.R92W mutation, suggesting that in 46,XY individuals, the mutation would cause various gonadal phenotypes. We review and discuss the general role of the R92W mutation in sexual development. © 2018 S. Karger AG, Basel.

De novo Transcriptome Analysis of Portunus trituberculatus Ovary and Testis by RNA-Seq: Identification of Genes Involved in Gonadal Development

PubMed Central

Meng, Xian-liang; Liu, Ping; Jia, Fu-long; Li, Jian; Gao, Bao-Quan

2015-01-01

The swimming crab Portunus trituberculatus is a commercially important crab species in East Asia countries. Gonadal development is a physiological process of great significance to the reproduction as well as commercial seed production for P. trituberculatus. However, little is currently known about the molecular mechanisms governing the developmental processes of gonads in this species. To open avenues of molecular research on P. trituberculatus gonadal development, Illumina paired-end sequencing technology was employed to develop deep-coverage transcriptome sequencing data for its gonads. Illumina sequencing generated 58,429,148 and 70,474,978 high-quality reads from the ovary and testis cDNA library, respectively. All these reads were assembled into 54,960 unigenes with an average sequence length of 879 bp, of which 12,340 unigenes (22.45% of the total) matched sequences in GenBank non-redundant database. Based on our transcriptome analysis as well as published literature, a number of candidate genes potentially involved in the regulation of gonadal development of P. trituberculatus were identified, such as FAOMeT, mPRγ, PGMRC1, PGDS, PGER4, 3β-HSD and 17β-HSDs. Differential expression analysis generated 5,919 differentially expressed genes between ovary and testis, among which many genes related to gametogenesis and several genes previously reported to be critical in differentiation and development of gonads were found, including Foxl2, Wnt4, Fst, Fem-1 and Sox9. Furthermore, 28,534 SSRs and 111,646 high-quality SNPs were identified in this transcriptome dataset. This work represents the first transcriptome analysis of P. trituberculatus gonads using the next generation sequencing technology and provides a valuable dataset for understanding molecular mechanisms controlling development of gonads and facilitating future investigation of reproductive biology in this species. The molecular markers obtained in this study will provide a fundamental basis for population genetics and functional genomics in P. trituberculatus and other closely related species. PMID:26042806

Developmental staging of male murine embryonic gonad by SAGE analysis

PubMed Central

Lee, Tin-Lap; Li, Yunmin; Alba, Diana; Vong, Queenie P.; Wu, Shao-Ming; Baxendale, Vanessa; Rennert, Owen M.; Lau, Yun-Fai Chris; Chan, Wai-Yee

2012-01-01

Despite the identification of key genes such as Sry integral to embryonic gonadal development, the genomic classification and identification of chromosomal activation of this process is still poorly understood. To better understand the genetic regulation of gonadal development, we performed Serial Analysis of Gene Expression (SAGE) to profile the genes and novel transcripts, and an average of 152,000 tags from male embryonic gonads at E10.5 (embryonic day 10.5), E11.5, E12.5, E13.5, E15.5 and E17.5 were analyzed. A total of 275,583 non-singleton tags that do not map to any annotated sequence were identified in the six gonad libraries, and 47,255 tags were mapped to 24,975 annotated sequences, among which 987 sequences were uncharacterized. Utilizing an unsupervised pattern identification technique, we established molecular staging of male gonadal development. Rather than providing a static descriptive analysis, we developed algorithms to cluster the SAGE data and assign SAGE tags to a corresponding chromosomal position; these data are displayed in chromosome graphic format. A prominent increase in global genomic activity from E10.5 to E17.5 was observed. Important chromosomal regions related to the developmental processes were identified and validated based on established mouse models with developmental disorders. These regions may represent markers for early diagnosis for disorders of male gonad development as well as potential treatment targets. PMID:19376482

Prevalence and Physical Distribution of SRY in the Gonads of a Woman with Turner Syndrome: Phenotypic Presentation, Tubal Formation, and Malignancy Risk.

PubMed

Baer, Tamar G; Freeman, Christopher E; Cujar, Claudia; Mansukhani, Mahesh; Singh, Bahadur; Chen, Xiaowei; Abellar, Rosanna; Oberfield, Sharon E; Levy, Brynn

2017-01-01

Although monosomy X is the most common karyotype in patients with Turner syndrome, the presence of Y chromosome material has been observed in about 10% of patients. Y chromosome material in patients with Turner syndrome poses an increased risk of gonadoblastoma and malignant transformation. We report a woman with a diagnosis of Turner syndrome at 12 years of age, without signs of virilization, and karyotype reported as 46,X,del(X)(q13). At 26 years, cytogenetic studies indicated the patient to be mosaic for monosomy X and a cell line that contained a du-plicated Yq chromosome. Bilateral gonadectomy was performed and revealed streak gonads, without evidence of gonadoblastoma. Histological analysis showed ovarian stromal cells with few primordial tubal structures. FISH performed on streak gonadal tissue showed a heterogeneous distribution of SRY, with exclusive localization to the primordial tubal structures. DNA extraction from the gonadal tissue showed a 6.5% prevalence of SRY by microarray analysis, contrasting the 86% prevalence in the peripheral blood sample. This indicates that the overall gonadal sex appears to be determined by the majority gonosome complement in gonadal tissue in cases of sex chromosome mosaicism. This case also raises questions regarding malignancy risk associated with Y prevalence and tubal structures in gonadal tissue. © 2017 S. Karger AG, Basel.

Potential miRNA regulators of differential HPG axis gene expression between low egg producing and high egg producing turkey hens

USDA-ARS?s Scientific Manuscript database

Expression differences exist in key genes of the hypothalamo-pituitary-gonadal (HPG) axis in low egg producing hens (LEPH) and high egg producing hens (HEPH); however, regulation of these differences is unknown. MicroRNAs (miRNAs) are small non-coding RNAs that play a role in post-transcriptional re...

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,…

Interactions of the hormones leptin, ghrelin, adiponectin, resistin, and PYY3-36 with the reproductive system.

PubMed

Budak, Erdal; Fernández Sánchez, Manuel; Bellver, José; Cerveró, Ana; Simón, Carlos; Pellicer, Antonio

2006-06-01

To summarize the effects of novel hormones (leptin, ghrelin, adiponectin, resistin, and PYY3-36) secreted from adipose tissue and the gastrointestinal tract that have been discovered to exert different effects on several reproductive functions, such as the hypothalamic-pituitary-gonadal axis, embryo development, implantation physiology, and clinically relevant conditions. A MEDLINE computer search was performed to identify relevant articles. Leptin and ghrelin exert important roles on body weight regulation, eating behavior, and reproduction, acting on the central nervous system and target reproductive organs. As a marker of adequate nutritional stores, these hormones may act on the central nervous system to initiate the complex process of puberty and maintain normal reproductive function. In addition, leptin and ghrelin and their receptors are involved in reproductive events such as gonadal function, embryo development, and embryo-endometrial interaction. Leptin and ghrelin and other adipose tissue-secreted hormones have significant effects on reproduction. Acting through the brain, these hormones may serve as links between adipose tissue and the reproductive system to supply and regulate energy needs for normal reproduction and pregnancy. Future studies are needed to further clarify the role of these hormones in reproductive events and other related gynecological conditions.

Sex Reversal in Birds.

PubMed

Major, Andrew T; Smith, Craig A

2016-01-01

Sexual differentiation in birds is controlled genetically as in mammals, although the sex chromosomes are different. Males have a ZZ sex chromosome constitution, while females are ZW. Gene(s) on the sex chromosomes must initiate gonadal sex differentiation during embryonic life, inducing paired testes in ZZ individuals and unilateral ovaries in ZW individuals. The traditional view of avian sexual differentiation aligns with that expounded for other vertebrates; upon sexual differentiation, the gonads secrete sex steroid hormones that masculinise or feminise the rest of the body. However, recent studies on naturally occurring or experimentally induced avian sex reversal suggest a significant role for direct genetic factors, in addition to sex hormones, in regulating sexual differentiation of the soma in birds. This review will provide an overview of sex determination in birds and both naturally and experimentally induced sex reversal, with emphasis on the key role of oestrogen. We then consider how recent studies on sex reversal and gynandromorphic birds (half male:half female) are shaping our understanding of sexual differentiation in avians and in vertebrates more broadly. Current evidence shows that sexual differentiation in birds is a mix of direct genetic and hormonal mechanisms. Perturbation of either of these components may lead to sex reversal. © 2016 S. Karger AG, Basel.

Genome-Wide Identification and Transcriptome-Based Expression Profiling of the Sox Gene Family in the Nile Tilapia (Oreochromis niloticus)

PubMed Central

Wei, Ling; Yang, Chao; Tao, Wenjing; Wang, Deshou

2016-01-01

The Sox transcription factor family is characterized with the presence of a Sry-related high-mobility group (HMG) box and plays important roles in various biological processes in animals, including sex determination and differentiation, and the development of multiple organs. In this study, 27 Sox genes were identified in the genome of the Nile tilapia (Oreochromis niloticus), and were classified into seven groups. The members of each group of the tilapia Sox genes exhibited a relatively conserved exon-intron structure. Comparative analysis showed that the Sox gene family has undergone an expansion in tilapia and other teleost fishes following their whole genome duplication, and group K only exists in teleosts. Transcriptome-based analysis demonstrated that most of the tilapia Sox genes presented stage-specific and/or sex-dimorphic expressions during gonadal development, and six of the group B Sox genes were specifically expressed in the adult brain. Our results provide a better understanding of gene structure and spatio-temporal expression of the Sox gene family in tilapia, and will be useful for further deciphering the roles of the Sox genes during sex determination and gonadal development in teleosts. PMID:26907269

Genome-Wide Identification and Transcriptome-Based Expression Profiling of the Sox Gene Family in the Nile Tilapia (Oreochromis niloticus).

PubMed

Wei, Ling; Yang, Chao; Tao, Wenjing; Wang, Deshou

2016-02-23

The Sox transcription factor family is characterized with the presence of a Sry-related high-mobility group (HMG) box and plays important roles in various biological processes in animals, including sex determination and differentiation, and the development of multiple organs. In this study, 27 Sox genes were identified in the genome of the Nile tilapia (Oreochromis niloticus), and were classified into seven groups. The members of each group of the tilapia Sox genes exhibited a relatively conserved exon-intron structure. Comparative analysis showed that the Sox gene family has undergone an expansion in tilapia and other teleost fishes following their whole genome duplication, and group K only exists in teleosts. Transcriptome-based analysis demonstrated that most of the tilapia Sox genes presented stage-specific and/or sex-dimorphic expressions during gonadal development, and six of the group B Sox genes were specifically expressed in the adult brain. Our results provide a better understanding of gene structure and spatio-temporal expression of the Sox gene family in tilapia, and will be useful for further deciphering the roles of the Sox genes during sex determination and gonadal development in teleosts.

Thyroid hormone actions on male reproductive system of teleost fish.

PubMed

Tovo-Neto, Aldo; da Silva Rodrigues, Maira; Habibi, Hamid R; Nóbrega, Rafael Henrique

2018-04-17

Thyroid hormones (THs) play important roles in the regulation of many biological processes of vertebrates, such as growth, metabolism, morphogenesis and reproduction. An increasing number of studies have been focused on the involvement of THs in the male reproductive system of vertebrates, in particular of fish. Therefore, this mini-review aims to summarize the main findings on THs role in male reproductive system of fish, focusing on sex differentiation, testicular development and spermatogenesis. The existing data in the literature have demonstrated that THs exert their roles at the different levels of the hypothalamic-pituitary-gonadal (HPG) axis. In general a positive correlation has been shown between THs and fish reproductive status; where THs are associated with testicular development, growth and maturation. Recently, the molecular mechanisms underlying the role of THs in spermatogenesis have been unraveled in zebrafish testis. THs promote germ cell proliferation and differentiation by increasing a stimulatory growth factor of spermatogenesis produced by Sertoli cells. In addition, THs enhanced the gonadotropin-induced androgen release in zebrafish testis. Next to their functions in the adult testis, THs are involved in the gonadal sex differentiation through modulating sex-related gene expression, and testicular development via regulation of Sertoli cell proliferation. In conclusion, this mini-review showed that THs modulate the male reproductive system during the different life stages of fish. The physiological and molecular mechanisms showed a link between the thyroid and reproduction, suggesting a possibly co-evolution and interdependence of these two systems. Copyright © 2018 Elsevier Inc. All rights reserved.

Gonadal Identity in the Absence of Pro-Testis Factor SOX9 and Pro-Ovary Factor Beta-Catenin in Mice1

PubMed Central

Nicol, Barbara; Yao, Humphrey H.-C.

2015-01-01

Sex-reversal cases in humans and genetic models in mice have revealed that the fate of the bipotential gonad hinges upon the balance between pro-testis SOX9 and pro-ovary beta-catenin pathways. Our central query was: if SOX9 and beta-catenin define the gonad's identity, then what do the gonads become when both factors are absent? To answer this question, we developed mouse models that lack either Sox9, beta-catenin, or both in the somatic cells of the fetal gonads and examined the morphological outcomes and transcriptome profiles. In the absence of Sox9 and beta-catenin, both XX and XY gonads progressively lean toward the testis fate, indicating that expression of certain pro-testis genes requires the repression of the beta-catenin pathway, rather than a direct activation by SOX9. We also observed that XY double knockout gonads were more masculinized than their XX counterpart. To identify the genes responsible for the initial events of masculinization and to determine how the genetic context (XX vs. XY) affects this process, we compared the transcriptomes of Sox9/beta-catenin mutant gonads and found that early molecular changes underlying the XY-specific masculinization involve the expression of Sry and 21 SRY direct target genes, such as Sox8 and Cyp26b1. These results imply that when both Sox9 and beta-catenin are absent, Sry is capable of activating other pro-testis genes and drive testis differentiation. Our findings not only provide insight into the mechanism of sex determination, but also identify candidate genes that are potentially involved in disorders of sex development. PMID:26108792

The interactive effect of dietary protein and vitamin levels on the depression of gonadal development in growing male rats kept under disturbed daily rhythm.

PubMed

Hanai, Miho; Esashi, Takatoshi

2007-04-01

The purpose of this study was to clarify the effects of nutrients on the gonadal development of male rats kept under constant darkness as a model of disturbed daily rhythm. The present study examined protein and vitamins, and their interactions. This study was based on three-way ANOVA; the three factors were lighting conditions, dietary protein and dietary vitamins, respectively. The levels of dietary protein were low or normal: 9% casein or 20% casein. The levels of dietary vitamins were low, normal or high: 1/3.3 of normal (AIN-93G diet) content, normal content, or three times the normal content, respectively. Other compositions were the same as those of the AIN-93G diet, and six kinds of experimental diet were prepared. Four-week-old rats (Fischer 344 strain) were kept under constant darkness or normal lighting (12-h light/dark cycle) for 4 wk. After 4 wk, the gonadal weights and serum testosterone content were evaluated. In the constant darkness groups (D-groups), the low-protein diet induced reduction of gonadal organ weights and serum testosterone concentrations. This reduction of gonadal organ weights was exacerbated by progressively higher levels of dietary vitamins. In the case of a normal-protein diet, the depression of gonadal development was not accelerated by high-vitamin intake. In the normal lighting groups (N-groups), the low-protein and high-vitamin diet slightly depressed gonadal development. These results suggest that the metabolism of protein and vitamins is different in rats being kept under constant darkness, and that excess dietary vitamins have an adverse effect on gonadal development in rats fed a low-protein diet.

Effect of SKI2670, a novel, orally active, non-peptide GnRH antagonist, on hypothalamic-pituitary-gonadal axis.

PubMed

Kim, Seon Mi; Yoo, Taekyung; Lee, So Young; Kim, Eun Jeong; Lee, Soo Min; Lee, Min Hee; Han, Min Young; Jung, Seung-Hyun; Choi, Jung-Hye; Ryu, Keun Ho; Kim, Hun-Taek

2015-10-15

Suppression of the hypothalamic-pituitary-gonadal axis has been widely utilized for the management of gonadal-hormone-dependent diseases such as endometriosis. Efforts to develop orally available gonadotropin-releasing hormone (GnRH) antagonists for the treatment of gonadal-hormone-dependent diseases led to the discovery of SKI2670, a novel non-peptide GnRH antagonist. The present study was undertaken to pharmacologically characterize SKI2670 in vitro and in vivo. We measured binding affinity and antagonistic activity of SKI2670 for the GnRH receptors. Immediate suppression of gonadotropins by single dosing of SKI2670 was examined in castrated monkeys. Subsequently, influence on gonadal hormones by prolonged administration of SKI2670 was assessed in naive female monkeys. To investigate in vivo efficacy of SKI2670, regression of ectopic implants by repeated administration of SKI2670 was examined in a rat endometriosis model. SKI2670 is a potent functional antagonist for the human GnRH receptor, with subnanomolar binding affinity. In castrated monkeys, single administration of SKI2670 lowered serum luteinizing hormone (LH) levels stronger with longer duration when compared to elagolix at equivalent doses. Moreover, repeated dosing of SKI2670 suppressed serum levels of gonadotropins and gonadal hormones in intact female monkeys while elagolix suppressed serum LH levels only. Finally, it exhibited regressive effects on ectopic implants in a rat endometriosis model without bone loss. Our findings demonstrate robust GnRH antagonistic efficacy of SKI2670 in animal models, suggesting that SKI2670-induced suppression of the hypothalamic-pituitary-gonadal axis may be beneficial for the treatment of gonadal-hormone-dependent diseases such as endometriosis in humans. Copyright © 2015 Elsevier Inc. All rights reserved.

Isolated 46,XY gonadal dysgenesis in two sisters caused by a Xp21.2 interstitial duplication containing the DAX1 gene.

PubMed

Barbaro, Michela; Oscarson, Mikael; Schoumans, Jacqueline; Staaf, Johan; Ivarsson, Sten A; Wedell, Anna

2007-08-01

Testis development is a tightly regulated process that requires an efficient and coordinated spatiotemporal action of many factors, and it has been shown that several genes involved in gonadal development exert a dosage effect. Chromosomal imbalances have been reported in several patients presenting with gonadal dysgenesis as part of severe dysmorphic phenotypes. We screened for submicroscopic DNA copy number variations in two sisters with an apparent normal 46,XY karyotype and female external genitalia due to gonadal dysgenesis, and in which mutations in known candidate genes had been excluded. By high-resolution tiling bacterial artificial chromosome array comparative genome hybridization, a submicroscopic duplication at Xp21.2 containing DAX1 (NR0B1) was identified. Using fluorescence in situ hybridization, multiple ligation probe amplification, and PCR, the rearrangement was further characterized. This revealed a 637-kb tandem duplication that in addition to DAX1 includes the four MAGEB genes, the hypothetical gene CXorf21, GK, and part of the MAP3K7IP3 gene. Sequencing and analysis of the breakpoint boundaries and duplication junction suggest that the duplication originated through a coupled homologous and nonhomologous recombination process. This represents the first duplication on Xp21.2 identified in patients with isolated gonadal dysgenesis because all previously described XY subjects with Xp21 duplications presented with gonadal dysgenesis as part of a more complex phenotype, including mental retardation and/or malformations. Thus, our data support DAX1 as a dosage sensitive gene responsible for gonadal dysgenesis and highlight the importance of considering DAX1 locus duplications in the evaluation of all cases of 46,XY gonadal dysgenesis.

Mortality, size of the gonads, and ultrastructure of primordial germ cell in chick embryos treated with gamma-irradiation or injected with donor cells.

PubMed

Maeda, T; Clark, M E; Etches, R J

1998-06-01

The effects of injection and/or gamma-irradiation prior to injection on mortality, size of the gonads, and ultrastructure of primordial germ cell (PGC) were examined after 5 d of incubation. The mortality of embryos injected with donor cells was significantly higher than that of control and irradiated embryos. All irradiated embryos were alive, although their development was delayed compared to those not exposed to irradiation. The size of the gonads of embryos injected with donor cells were similar to those of control embryos, however, the size of the gonads in irradiated embryos was significantly smaller than those of control embryos. The number of PGC in the gonads was significantly decreased by irradiation. There was no notable effect of irradiation or injection on the nuclei and cytoplasmic organelles in PGC.

Identification and profiling of Cyprinus carpio microRNAs during ovary differentiation by deep sequencing.

PubMed

Wang, Fang; Jia, Yongfang; Wang, Po; Yang, Qianwen; Du, QiYan; Chang, ZhongJie

2017-04-28

MicroRNAs (miRNAs) are endogenous small non-coding RNAs that regulate gene expression by targeting specific mRNAs. However, the possible role of miRNAs in the ovary differentiation and development of fish is not well understood. In this study, we examined the expression profiles and differential expression of miRNAs during three key stages of ovarian development and different developmental stages in common carp Cyprinus carpio. A total of 8765 miRNAs were identified, including 2155 conserved miRNAs highly conserved among various species, 145 miRNAs registered in miRBase for common carp, and 6505 novel miRNAs identified in common carp for the first time. Comparison of miRNA expression profiles among the five libraries identified 714 co-expressed and 2382 specific expressed miRNAs. Overall, 150, 628, and 431 specifically expressed miRNAs were identified in primordial gonad, juvenile ovary, and adult ovary, respectively. MiR-6758-3p, miR-3050-5p, and miR-2985-3p were highly expressed in primordial gonad, miR-3544-5p, miR-6877-3p, and miR-9086-5p were highly expressed in juvenile ovary, and miR-154-3p, miR-5307-5p, and miR-3958-3p were highly expressed in adult ovary. Predicted target genes of specific miRNAs in primordial gonad were involved in many reproductive biology signaling pathways, including transforming growth factor-β, Wnt, oocyte meiosis, mitogen-activated protein kinase, Notch, p53, and gonadotropin-releasing hormone pathways. Target-gene prediction revealed upward trends in miRNAs targeting male-bias genes, including dmrt1, atm, gsdf, and sox9, and downward trends in miRNAs targeting female-bias genes including foxl2, smad3, and smad4. Other sex-related genes such as sf1 were also predicted to be miRNA target genes. This comprehensive miRNA transcriptome analysis demonstrated differential expression profiles of miRNAs during ovary development in common carp. These results could facilitate future exploitation of the sex-regulatory roles and mechanisms of miRNAs, especially in primordial gonads, while the specifically expressed miRNAs represent candidates for studying the mechanisms of ovary determination in Yellow River carp.

Concentrations of pituitary, gonadal and adrenal hormones in serum of laying and broody white rock hens (Gallus domesticus).

PubMed

Bedrak, E; Harvey, S; Chadwick, A

1981-05-01

Diurnal variations in circulating concentrations of LH, GH, prolactin, corticosterone, oestradiol, progesterone and testosterone were followed in laying and broody White Rock domestic fowl. Throughout the 24 h study prolactin concentrations in serum were consistently (two- to fourfold) higher in broody than in laying birds, in which the prolactin level varied with the light:darkness or ovulatory cycles. Concentrations of GH in serum tended to be lower in broody birds but in both groups were very variable and showed no obvious relationship with either the lighting or ovulatory cycles. Broodiness was also characterized by low LH and gonadal steroid levels and by the absence of preovulatory peaks in the serum concentrations of these hormones. A diurnal rhythm in corticosterone was observed in both the laying and broody birds, with high levels during the period of darkness. Corticosterone concentrations were markedly higher in the broody birds than in laying birds during most of the 24 h study. No diurnal rhythm in the blood haematocrit level was observed in either group, although the level was generally lower in broody birds. This difference, however, was insufficient to account for the lower LH and gonadal steroid levels in the broody birds. The results suggest that prolactin is involved in the initiation or maintenance of broodiness in the fowl and the possibility of an antigonadal role for the hormone is discussed.

Germ cell transplantation using sexually competent fish: an approach for rapid propagation of endangered and valuable germlines.

PubMed

Majhi, Sullip K; Hattori, Ricardo S; Yokota, Masashi; Watanabe, Seiichi; Strüssmann, Carlos A

2009-07-02

The transplantation of germ cells into adult recipient gonads is a tool with wide applications in animal breeding and conservation of valuable and/or endangered species; it also provides a means for basic studies involving germ cell (GC) proliferation and differentiation. Here we describe the establishment of a working model for xenogeneic germ cell transplantation (GCT) in sexually competent fish. Spermatogonial cells isolated from juveniles of one species, the pejerrey Odontesthes bonariensis (Atherinopsidae), were surgically transplanted into the gonads of sexually mature Patagonian pejerrey O. hatcheri, which have been partially depleted of endogenous GCs by a combination of Busulfan (40 mg/kg) and high water temperature (25 degrees C) treatments. The observation of the donor cells' behavior showed that transplanted spermatogonial cells were able to recolonize the recipients' gonads and resume spermatogenesis within 6 months from the GCT. The presence of donor-derived gametes was confirmed by PCR in 20% of the surrogate O. hatcheri fathers at 6 months and crosses with O. bonariensis mothers produced hybrids and pure O. bonariensis, with donor-derived germline transmission rates of 1.2-13.3%. These findings indicate that transplantation of spermatogonial cells into sexually competent fish can shorten considerably the production time of donor-derived gametes and offspring and could play a vital role in germline conservation and propagation of valued and/or endangered fish species.

Expression of gonadotropin subunits in roach (Rutilus rutilus, Cyprinidae) infected with plerocercoids of the tapeworm Ligula intestinalis (Cestoda).

PubMed

Trubiroha, Achim; Wuertz, Sven; Frank, Sabrina N; Sures, Bernd; Kloas, Werner

2009-11-01

Plerocercoids of the tapeworm Ligula intestinalis (Cestoda: Bothriocephalidea) have been reported to inhibit gametogenesis of their intermediate fish hosts. However, mechanistic studies are rare and the proximate cues leading to impaired reproduction still remain unknown. In the present study we investigated the effects of infection by L. intestinalis on reproductive parameters of roach (Rutilus rutilus, Cyprinidae), a common fish host of this parasite. Field studies on roach demonstrated that in both genders infection prevented gonad development. As revealed by quantitative PCR, infection was accompanied by essentially lower pituitary expression of follicle-stimulating hormone beta-subunit (FSHbeta) and luteinizing hormone beta-subunit (LHbeta) mRNA compared with uninfected roach, providing clear evidence for gonadotropin-insufficiency as the cause of arrested gametogenesis. Under controlled laboratory conditions infected roach showed lower mRNA levels of FSHbeta but not of LHbeta, despite histology revealing similar gonad stages as in uninfected conspecifics. These findings indicate the involvement of FSH rather than LH in mediating effects of infection early during gonad development in roach. Moreover, the impact of L. intestinalis on reproductive parameters of roach appeared to be independent of the parasite burden. Together, these data provide valuable information on the role of FSH and LH as mediators of parasite-induced sterilization in a vertebrate and implicate the selective inhibition of host reproduction by L. intestinalis as a natural source of endocrine disruption in fish.

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 or...

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 or...

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 or...

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 or...

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 or...

MAP3K1-related gonadal dysgenesis: Six new cases and review of the literature.

PubMed

Granados, Andrea; Alaniz, Veronica I; Mohnach, Lauren; Barseghyan, Hayk; Vilain, Eric; Ostrer, Harry; Quint, Elisabeth H; Chen, Ming; Keegan, Catherine E

2017-06-01

Investigation of disorders of sex development (DSD) has resulted in the discovery of multiple sex-determining genes. MAP3K1 encodes a signal transduction regulator in the sex determination pathway and is emerging as one of the more common genes responsible for 46,XY DSD presenting as complete or partial gonadal dysgenesis. Clinical assessment, endocrine evaluation, and genetic analysis were performed in six individuals from four unrelated families with 46,XY DSD. All six individuals were found to have likely pathogenic MAP3K1 variants. Three of these individuals presented with complete gonadal dysgenesis, characterized by bilateral streak gonads with typical internal and external female genitalia, while the other three presented with partial gonadal dysgenesis, characterized by incomplete testicular development, resulting in clitoral hypertrophy with otherwise typical female external genitalia. Testing for MAP3K1 variants should be considered in patients with 46,XY complete or partial gonadal dysgenesis, particularly in families with multiple members affected with 46,XY DSD. Identification of a MAP3K1 variant should prompt an evaluation for DSD in female siblings of the proband. © 2017 Wiley Periodicals, Inc.

Preliminary Study On Gonad Maturity Stages of the Sea Cucumber Paracaudina australis from Kenjeran Water, Surabaya, Indonesia

NASA Astrophysics Data System (ADS)

Widianingsih, Widianingsih; Zaenuri, Muhammad; Anggoro, Sutrisno; Pancasakti Kusumaningrum, Hermin; Hartati, Retno

2018-02-01

The holothurian Paracaudina australis is belong to family Caudinidae, ordo Molpadida and class Holothuroidea. This species is among the most common holothurian widely distributed in the tropical water. The purpose of this reseach is to do preliminary study on maturity stages of sea cucumber Paracaudina australis from Kenjeran Water, Surabaya, Indonesia. This research was conducted on April 2016. Samples were collected randomly on the Kenjeran Water, Surabaya. The result showed that there are five stages of gonad maturity. At the stage of maturity 1, the gonad was not clearly distinguished, there were unbranched small tubule. At the stage of maturity 2, there were small branched of tubules. At this stage, gonad can be differentiated between male and female. At the stage of maturity 3, tubule can been branched not only for male but also female. At the stage of maturity 4, the gonad was good mature, there were clearly branched tubule. At the stage of matury 5, there were generally had empty tubule except for a few relict unreleased spermatozoa. At female gonad, there were shrunken tubule and relict oocytes were presented in the lumen of the tubule.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

The union of somatic gonad precursors and primordial germ cells during C. elegans embryogenesis

PubMed Central

Rohrschneider, Monica R.; Nance, Jeremy

2013-01-01

Somatic gonadal niche cells control the survival, differentiation, and proliferation of germline stem cells. The establishment of this niche-stem cell relationship is critical, and yet the precursors to these two cell types are often born at a distance from one another. The simple C. elegans gonadal primordium, which contains two somatic gonad precursors (SGPs) and two primordial germ cells (PGCs), provides an accessible model for determining how stem cell and niche cell precursors first assemble during development. To visualize the morphogenetic events that lead to formation of the gonadal primordium, we generated transgenic strains to label the cell membranes of the SGPs and PGCs and captured time-lapse movies as the gonadal primordium formed. We identify three distinct phases of SGP behavior: posterior migration along the endoderm towards the PGCs, extension of a single long projection around the adjacent PGC, and a dramatic wrapping over the PGC surfaces. We show that the endoderm and PGCs are dispensable for SGP posterior migration and initiation of projections. However, both tissues are required for the final positioning of the SGPs and the morphology of their projections, and PGCs are absolutely required for SGP wrapping behaviors. Finally, we demonstrate that the basement membrane component laminin, which localizes adjacent to the developing gonadal primordium, is required to prevent the SGPs from over-extending past the PGCs. Our findings provide a foundation for understanding the cellular and molecular regulation of the establishment of a niche-stem cell relationship. PMID:23562590

Emergence, development, and maturity of the gonad of two species of chitons "sea cockroach" (Mollusca: Polyplacophora) through the early life stages.

PubMed

Avila-Poveda, Omar Hernando; Abadia-Chanona, Quetzalli Yasú

2013-01-01

This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or "early life stages" were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aX(b) . A total of 125 chitons (4≤TL≤40 mm, in total length "TL") were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods ("Pw" without gonad, "Pe" gonad emergence, and "Pf" gonadal sac formed) and four stages ("S0" gametocytogenesis, "S1" gametogenesis, "S2" mature, and "S3" spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13-14.32 mm, Pe 10.32-16.93 mm, Pf 12.99-25.01 mm, S0 16.08-24.34 mm (females) and 19.51-26.60 mm (males), S1 27.15-35.63 mm (females) and 23.45-32.27 mm (males), S2 24.48-40.24 mm (females) and 25.45-32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management.

Dimorphic expression of sex-related genes in different gonadal development stages of sterlet, Acipenser ruthenus, a primitive fish species.

PubMed

Wang, Wei; Zhu, Hua; Dong, Ying; Tian, ZhaoHui; Dong, Tian; Hu, HongXia; Niu, CuiJuan

2017-12-01

Molecular mechanism of sex determination and differentiation of sturgeon, a primitive fish species, is extraordinarily important due to the valuable caviar; however, it is still poorly known. The present work aimed to identify the major genes involved in regulating gonadal development of sterlet, a small species of sturgeon, from 13 candidate genes which have been shown to relate to gonadal differentiation and development in other teleost fish. The sex and gonadal development of sterlets were determined by histological observation and levels of sex steroids testosterone (T), 11-ketotestosterone (11-KT), and 17β-estradiol (E2) in serum. Sexually dimorphic gene expressions were investigated. The results revealed that gonadal development were asynchronous in 2-year-old male and female sterlets with the testes in early or mid-spermatogenesis and the ovaries in chromatin nucleolus stage or perinucleolus stage, respectively. The levels of T and E2 were not significantly different between sexes or different gonadal development stages while 11-KT had the higher level in mid-spermatogenesis testis stage. In all the investigated gonadal development stages, gene dmrt1 and hsd11b2 were expressed higher in male whereas foxl2 and cyp19a1 were expressed higher in female. Thus, these genes provided the promising markers for sex identification of sterlet. It was unexpected that dkk1 and dax1 had significantly higher expression in ovarian perinucleolus stage than in ovarian chromatin nucleolus stage and in the testis, suggesting that these two genes had more correlation with ovarian development than with the testis, contrary to the previous reports in other vertebrates. Testicular development-related genes (gsdf and amh) and estrogen receptor genes (era and erb) differentially expressed at different testis or ovary development stages, but their expressions were not absolutely significantly different in male and female, depending on the gonadal development stage. Expression of androgen receptor gene ar or rspo, which was supposed to be related to ovarian development, presented no difference between gonadal development stages investigated in this study whenever in male or female.

Unusual disease conditions in pet and aviary birds.

PubMed

Panigrahy, B; Mathewson, J J; Hall, C F; Grumbles, L C

1981-02-15

Ninety percent ot 100% mortality in budgerigar (Melopsittacus undulatus) nestlings from 2 aviaries was attributed to giardiasis. Treatment with dimetridazole in drinking water was effective in controlling mortality. Aeromonas hydrophila infection incriminated in acute deaths of aviary canaries (Serinus canarius) was successfully treated with chlortetracycline. Aeromonas hydrophila also was isolated in pure culture from a toucan (ramphastos toco) with acute nephrosis and a cockatiel (Nymphicus hollandicus) with chlamydiosis (psittacosis). Coccidiosis associated with hemorrhagic enteritis, diarrhea, and mortality was diagnosed in budgerigars originating from 3 aviaries. Sporulated oocysts from 1 group of budgerigars were identified as Eimera sp. Sulfamethazine in drinking water was an effective treatment.

Expression of the Wilms' tumor gene WT1 in the murine urogenital system.

PubMed

Pelletier, J; Schalling, M; Buckler, A J; Rogers, A; Haber, D A; Housman, D

1991-08-01

The Wilms' tumor gene WT1 is a recessive oncogene that encodes a putative transcription factor implicated in nephrogenesis during kidney development. In this report we analyze expression of WT1 in the murine urogenital system. WT1 is expressed in non-germ-cell components of the testis and ovaries in both young and adult mice. In situ mRNA hybridization studies demonstrate that WT1 is expressed in the granulosa and epithelial cells of ovaries, the Sertoli cells of the testis, and in the uterine wall. In addition to the 3.1-kb WT1 transcript detected by Northern blotting of RNA from kidney, uterus, and gonads, there is an approximately 2.5-kb WT1-related mRNA species in testis. The levels of WT1 mRNA in the gonads are among the highest observed, surpassing amounts detected in the embryonic kidney. During development, these levels are differentially regulated, depending on the sexual differentiation of the gonad. Expression of WT1 mRNA in the female reproductive system does not fluctuate significantly from days 4 to 40 postpartum. In contrast, WT1 mRNA levels in the tesis increase steadily after birth, reaching their highest expression levels at day 8 postpartum and decreasing slightly as the animal matures. Expression of WT1 in the gonads is detectable as early as 12.5 days postcoitum (p.c.). As an initial step toward exploring the tissue-specific expression of WT1, DNA elements upstream of WT1 were cloned and sequenced. Three putative transcription initiation sites, utilized in testis, ovaries, and uterus, were mapped by S1 nuclease protection assays. The sequences surrounding these sites have a high G + C content, and typical upstream CCAAT and TATAA boxes are not present. These studies allowed us to identify the translation initiation site for WT1 protein synthesis. We have also used an epitope-tagging protocol to demonstrate that WT1 is a nuclear protein, consistent with its role as a transcription factor. Our results demonstrate regulation of WT1 expression during development of the gonads, implicate WT1 in genitourinary development, and provide a molecular framework toward understanding genitourinary defects observed among hereditary cases of Wilms' tumor.

The Drosophila actin regulator ENABLED regulates cell shape and orientation during gonad morphogenesis.

PubMed

Sano, Hiroko; Kunwar, Prabhat S; Renault, Andrew D; 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.

Ovotesticular disorder of sexual development and a rare 46,XX/47,XXY karyotype.

PubMed

Ozsu, Elif; Mutlu, Gul Yesiltepe; Cizmecioglu, Filiz M; Ekingen, Gülsen; Muezzinoglu, Bahar; Hatun, Sukru

2013-01-01

Ovotesticular disorder of sexual development (DSD) is characterized by the presence of both ovarian and testicular tissues in the same individual. The most common karyotype is 46,XX. Here, we report the case of a boy with a 46,XX/47,XXY karyotype diagnosed as ovotesticular DSD by gonadal biopsy. A 5-month-old boy presented with hypospadias, unilateral cryptorchidism, and a micropenis. Pelvic magnetic resonance imaging revealed a suspicious gonad tissue that is solid in structure in the right scrotum and a suspicious gonad that is cystic in structure in the left inguinal canal. He underwent a diagnostic laparoscopy. Cytogenetic analysis of peripheral blood revealed a 46,XX/47,XXY karyotype. Histopathologic examination of the left gonad showed ovarian tissue containing primordial follicles with ipsilateral undifferentiated tuba uterina. The right gonad showed immature testis tissue. He underwent left gonadectomy and hypospadias repair, and was raised as a male. Through this rare case, we highlight the importance of histological and cytogenetic investigation in DSD.

Global Survey of Protein Expression during Gonadal Sex Determination in Mice*

PubMed Central

Ewen, Katherine; Baker, Mark; Wilhelm, Dagmar; Aitken, R. John; Koopman, Peter

2009-01-01

The development of an embryo as male or female depends on differentiation of the gonads as either testes or ovaries. A number of genes are known to be important for gonadal differentiation, but our understanding of the regulatory networks underpinning sex determination remains fragmentary. To advance our understanding of sexual development beyond the transcriptome level, we performed the first global survey of the mouse gonad proteome at the time of sex determination by using two-dimensional nanoflow LC-MS/MS. The resulting data set contains a total of 1037 gene products (154 non-redundant and 883 redundant proteins) identified from 620 peptides. Functional classification and biological network construction suggested that the identified proteins primarily serve in RNA post-transcriptional modification and trafficking, protein synthesis and folding, and post-translational modification. The data set contains potential novel regulators of gonad development and sex determination not revealed previously by transcriptomics and proteomics studies and more than 60 proteins with potential links to human disorders of sexual development. PMID:19617587

Gene Expression Profiling Reveals Potential Players of Left-Right Asymmetry in Female Chicken Gonads.

PubMed

Wan, Zhiyi; Lu, Yanan; Rui, Lei; Yu, Xiaoxue; Yang, Fang; Tu, Chengfang; Li, Zandong

2017-06-20

Most female birds develop only a left ovary, whereas males develop bilateral testes. The mechanism underlying this process is still not completely understood. Here, we provide a comprehensive transcriptional analysis of female chicken gonads and identify novel candidate side-biased genes. RNA-Seq analysis was carried out on total RNA harvested from the left and right gonads on embryonic day 6 (E6), E12, and post-hatching day 1 (D1). By comparing the gene expression profiles between the left and right gonads, 347 differentially expressed genes (DEGs) were obtained on E6, 3730 were obtained on E12, and 2787 were obtained on D1. Side-specific genes were primarily derived from the autosome rather than the sex chromosome. Gene ontology and pathway analysis showed that the DEGs were most enriched in the Piwi-interactiing RNA (piRNA) metabolic process, germ plasm, chromatoid body, P granule, neuroactive ligand-receptor interaction, microbial metabolism in diverse environments, and methane metabolism. A total of 111 DEGs, five gene ontology (GO) terms, and three pathways were significantly different between the left and right gonads among all the development stages. We also present the gene number and the percentage within eight development-dependent expression patterns of DEGs in the left and right gonads of female chicken.

Impact of a gestational exposure to diesel exhaust on offspring gonadal development: experimental study in the rabbit.

PubMed

Bourdon, M; Torres-Rovira, L; Monniaux, D; Faure, C; Levy, R; Tarrade, A; Rousseau-Ralliard, D; Chavatte-Palmer, P; Jolivet, G

2018-06-18

The aim of the present work was to address experimentally the possible impact of exposure to air pollution during gestation on the differentiation and function of the gonads of the offspring using a rabbit model. Rabbits were exposed daily to diluted diesel exhaust gas or filtered air from the 3rd until the 27th day of gestation, during which time germ cells migrate in genital ridges and divide, and fetal sex is determined. Offspring gonads were collected shortly before birth (28th day of gestation) or after puberty (7.5 months after birth). The structure of the gonads was analyzed by histological and immunohistological methods. Serum concentrations of testosterone and anti-Müllerian hormone were determined using ELISA. The morphology and the endocrine function of the gonads collected just at the arrest of the exposure were similar in polluted and control animals in both sexes. No differences were observed as well in gonads collected after puberty. Sperm was collected at the head of the epididymis in adults. Sperm motility and DNA fragmentation were measured. Among all parameters analyzed, only the sperm DNA fragmentation rate was increased three-fold in exposed males. Mechanisms responsible for these modifications and their physiological consequences are to be further clarified.

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. © 2016 AlphaMed Press.

Mutation of foxl2 or cyp19a1a Results in Female to Male Sex Reversal in XX Nile Tilapia.

PubMed

Zhang, Xianbo; Li, Mengru; Ma, He; Liu, Xingyong; Shi, Hongjuan; Li, Minghui; Wang, Deshou

2017-08-01

It is well accepted that Forkhead box protein L2 (Foxl2) and aromatase (Cyp19a1; the enzyme responsible for estrogen synthesis) are critical for ovarian development in vertebrates. Knockouts of Foxl2 and Cyp19a1 in goat, mouse, and zebrafish have revealed similar but not identical functions across species. Functional analyses of these two genes in other animals are needed to elucidate their conserved roles in vertebrate sexual development. In this study, we established foxl2 and cyp19a1a mutant lines in Nile tilapia. Both foxl2-/- and cyp19a1a-/- XX fish displayed female-to-male sex reversal. Sf1, Dmrt1, and Gsdf were upregulated in the foxl2-/- and the cyp19a1a-/- XX gonads. Downregulation of Cyp19a1a and serum estradiol-17β level, and upregulation of Cyp11b2 and serum 11-ketotestosterone level were observed in foxl2-/- XX fish. The mutant phenotype of foxl2-/- XX individuals could be rescued by 17β-estradiol treatment from 5 to 30 days after hatching (dah). Upregulation of Star1, the enzyme involved in androgen production in tilapia, was also observed in the foxl2-/- XX gonad at 30 and 90 dah. In vitro promoter analyses consistently demonstrated that Foxl2 could suppress the transcription of star1 in a dose-dependent manner. In addition, compared with the control XX gonad, fewer germ cells were detected in the foxl2-/- XX, cyp19a1a-/- XX, and control XY gonads 10 dah. These results demonstrate that Foxl2 promotes ovarian development by upregulating Cyp19a1a expression and repressing male pathway gene expression. These results extend the study of Foxl2 and Cyp19a1a loss of function to a commercially important fish species. Copyright © 2017 Endocrine Society.

Expression analysis of cyp11a1 during gonadal development, recrudescence and after hCG induction and sex steroid analog treatment in the catfish, Clarias batrachus.

PubMed

Rajakumar, Anbazhagan; Senthilkumaran, Balasubramanian

2014-10-01

In teleosts, the levels of steroids are critical for sexual development and hence, expression of steroidogenic enzyme genes and specific substrate availability are indispensable for gonadal steroidogenesis. Early stages of steroidogenesis specifically cholesterol to pregnenolone conversion by Cyp11a1 is crucial for estradiol and testosterone biosynthesis. Based on this, in this study, full length cDNA of cyp11a1 (2581bp) was cloned from catfish testis to investigate the importance of Cyp11a1 by analyzing the expression of cyp11a1 during gonadal development, seasonal reproductive cycle, after human chorionic gonadotropin (hCG) induction and sex steroid analog treatment. Phylogenetic analysis revealed that the Cyp11a1 is more conserved across teleosts. Tissue distribution analysis showed that the cyp11a1 expression was higher in the testis followed by the brain, head kidney, muscle and ovary compared to other tissues analyzed. High expression of cyp11a1 in the head kidney and muscle revealed that Cyp11a1 could potentially regulate the extra-gonadal and/or circulating steroid levels in teleosts. Developing and mature testes showed higher expression of cyp11a1 than the ovary of corresponding age group. Further, cyp11a1 expression was found to be higher during pre-spawning and spawning phases of testicular cycle and was upregulated by hCG, in vivo and in vitro, which indicates the possible regulation by gonadotropin. Exposure of methyltestosterone (1μg/L) and ethinylestradiol (1μg/L) for 21days during catfish testicular development showed lower cyp11a1 expression levels in the testis and brain indicating a certain feedback intervention. These results suggest possible role for Cyp11a1 in the testis development and recrudescence. Copyright © 2014 Elsevier Inc. All rights reserved.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zorlu, Faruk; Dugel, Gozde; Ozyigit, Gokhan

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 scrotalmore » 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.« less

Mercury concentrations in gonad, liver, and muscle of white sturgeon Acipenser transmontanus in the lower Columbia River.

PubMed

Webb, M A H; Feist, G W; Fitzpatrick, M S; Foster, E P; Schreck, C B; Plumlee, M; Wong, C; Gundersen, D T

2006-04-01

This study determined the partitioning of total mercury in liver, gonad, and cheek muscle of white sturgeon (Acipenser transmonatus) in the lower Columbia River. The relationship between tissue mercury concentrations and various physiologic parameters was assessed. White sturgeon were captured in commercial fisheries in the estuary and Bonneville, The Dalles, and John Day Reservoirs. Condition factor (CF), relative weight (Wr), and gonadosomatic index (GSI) were determined for each fish (n = 57). Gonadal tissue was examined histologically to determine sex and stage of maturity. Liver (n = 49), gonad (n = 49), and cheek muscle (n = 57) were analyzed for total mercury using cold-vapor atomic fluorescence spectrophotometry. Tissue protein concentrations were measured by ultraviolet-visible spectroscopy. Plasma was analyzed for testosterone (T), 11-ketotestosterone (KT), and 17ss-estradiol (E2) using radioimmunoassay. Mean tissue mercury concentrations were higher in muscle compared with liver and gonad at all sampling locations, except Bonneville Reservoir where mean liver mercury content was the highest tissue concentration observed in the study. Significant negative correlations between plasma androgens (T and KT) and muscle mercury content and plasma E2 and liver mercury content were found. A significant positive linear relationship between white sturgeon age and liver mercury concentrations was evident. Significant negative correlations between CF and relative weight and gonad and liver mercury content were found. In addition, immature male sturgeon with increased gonad mercury content had decreased GSIs. These results suggest that mercury, in the form of methylmercury, may have an effect on the reproductive potential of white sturgeon.

Intersex Occurrence in Rainbow Trout (Oncorhynchus mykiss) Male Fry Chronically Exposed to Ethynylestradiol

PubMed Central

Depiereux, Sophie; Liagre, Mélanie; Danis, Lorraine; De Meulder, Bertrand; Depiereux, Eric; Segner, Helmut; Kestemont, Patrick

2014-01-01

This study aimed to investigate the male-to-female morphological and physiological transdifferentiation process in rainbow trout (Oncorhynchus mykiss) exposed to exogenous estrogens. The first objective was to elucidate whether trout develop intersex gonads under exposure to low levels of estrogen. To this end, the gonads of an all-male population of fry exposed chronically (from 60 to 136 days post fertilization – dpf) to several doses (from environmentally relevant 0.01 µg/L to supra-environmental levels: 0.1, 1 and 10 µg/L) of the potent synthetic estrogen ethynylestradiol (EE2) were examined histologically. The morphological evaluations were underpinned by the analysis of gonad steroid (testosterone, estradiol and 11-ketotestosterone) levels and of brain and gonad gene expression, including estrogen-responsive genes and genes involved in sex differentiation in (gonads: cyp19a1a, ER isoforms, vtg, dmrt1, sox9a2; sdY; cyp11b; brain: cyp19a1b, ER isoforms). Intersex gonads were observed from the first concentration used (0.01 µg EE2/L) and sexual inversion could be detected from 0.1 µg EE2/L. This was accompanied by a linear decrease in 11-KT levels, whereas no effect on E2 and T levels was observed. Q-PCR results from the gonads showed downregulation of testicular markers (dmrt1, sox9a2; sdY; cyp11b) with increasing EE2 exposure concentrations, and upregulation of the female vtg gene. No evidence was found for a direct involvement of aromatase in the sex conversion process. The results from this study provide evidence that gonads of male trout respond to estrogen exposure by intersex formation and, with increasing concentration, by morphological and physiological conversion to phenotypic ovaries. However, supra-environmental estrogen concentrations are needed to induce these changes. PMID:25033040

Estimation of gonad volume, fecundity, and reproductive stage of shovelnose sturgeon using sonography and endoscopy with application to the endangered pallid sturgeon

USGS Publications Warehouse

Bryan, J.L.; Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Annis, M.L.

2007-01-01

Most species of sturgeon are declining in the Mississippi River Basin of North America including pallid (Scaphirhynchus albus F. and R.) and shovelnose sturgeons (S. platorynchus R.). Understanding the reproductive cycle of sturgeon in the Mississippi River Basin is important in evaluating the status and viability of sturgeon populations. We used non-invasive, non-lethal methods for examining internal reproductive organs of shovelnose and pallid sturgeon. We used an ultrasound to measure egg diameter, fecundity, and gonad volume; endoscope was used to visually examine the gonad. We found the ultrasound to accurately measure the gonad volume, but it underestimated egg diameter by 52%. After correcting for the measurement error, the ultrasound accurately measured the gonad volume but it was higher than the true gonad volume for stages I and II. The ultrasound underestimated the fecundity of shovelnose sturgeon by 5%. The ultrasound fecundity was lower than the true fecundity for stage III and during August. Using the endoscope, we viewed seven different egg color categories. Using a model selection procedure, the presence of four egg categories correctly predicted the reproductive stage ± one reproductive stage of shovelnose sturgeon 95% of the time. For pallid sturgeon, the ultrasound overestimated the density of eggs by 49% and the endoscope was able to view eggs in 50% of the pallid sturgeon. Individually, the ultrasound and endoscope can be used to assess certain reproductive characteristics in sturgeon. The use of both methods at the same time can be complementary depending on the parameter measured. These methods can be used to track gonad characteristics, including measuring Gonadosomatic Index in individuals and/or populations through time, which can be very useful when associating gonad characteristics with environmental spawning triggers or with repeated examinations of individual fish throughout the reproductive cycle.

ARX/Arx is expressed in germ cells during spermatogenesis in both marsupial and mouse.

PubMed

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

2014-03-01

The X-linked aristaless gene, ARX, is essential for the development of the gonads, forebrain, olfactory bulb, pancreas, and skeletal muscle in mice and humans. Mutations cause neurological diseases, often accompanied by ambiguous genitalia. There are a disproportionately high number of testis and brain genes on the human and mouse X chromosomes. It is still unknown whether the X chromosome accrued these genes during its evolution or whether genes that find themselves on the X chromosome evolve such roles. ARX was originally autosomal in mammals and remains so in marsupials, whereas in eutherian mammals it translocated to the X chromosome. In this study, we examined autosomal ARX in tammars and compared it with the X-linked Arx in mice. We detected ARX mRNA in the neural cells of the forebrain, midbrain and hindbrain, and olfactory bulbs in developing tammars, consistent with the expression in mice. ARX was detected by RT-PCR and mRNA in situ hybridization in the developing tammar wallaby gonads of both sexes, suggestive of a role in sexual development as in mice. We also detected ARX/Arx mRNA in the adult testis in both tammars and mice, suggesting a potential novel role for ARX/Arx in spermiogenesis. ARX transcripts were predominantly observed in round spermatids. Arx mRNA localization distributions in the mouse adult testis suggest that it escaped meiotic sex chromosome inactivation during spermatogenesis. Our findings suggest that ARX in the therian mammal ancestor already played a role in male reproduction before it was recruited to the X chromosome in eutherians.

Expression profile of amh/Amh during bi-directional sex change in the protogynous orange-spotted grouper Epinephelus coioides.

PubMed

Wu, Guan-Chung; Li, Hau-Wen; Tey, Wei-Guan; Lin, Chien-Ju; Chang, Ching-Fong

2017-01-01

Gonadal differentiation is tightly regulated by the initial sex determining gene and the downstream sex-related genes in vertebrates. However, sex change in fish can alter the sexual fate from one sex to the other. Chemical-induced maleness in the protogynous orange-spotted grouper is transient, and a reversible sex change occurs after the chemical treatment is withdrawn. We used these characteristics to study Amh signaling during bi-directional sex change in the grouper. We successfully induced the female-to-male sex change by chemical (aromatase inhibitor, AI, or methyltestosterone, MT) treatment. A dormant gonad (a low proliferation rate of early germ cells and no characteristics of both sexes) was found during the transient phase of reversible male-to-female sex change after the withdrawal of chemical administration. Our results showed that amh (anti-mullerian hormone) and its receptor amhr2 (anti-mullerian hormone receptor type 2) were significantly increased in the gonads during the process of female-to-male sex change. Amh is expressed in the Sertoli cells surrounding the type A spermatogonia in the female-to-male grouper. Male-related gene (dmrt1 and sox9) expression was immediately decreased in MT-terminated males during the reversible male-to-female sex change. However, Amh expression was found in the surrounding cells of type A spermatogonia-like cells during the transient phase of reversible male-to-female sex change. This phenomenon is correlated with the dormancy of type A spermatogonia-like cells. Thus, Amh signaling is suggested to play roles in regulating male differentiation during the female-to-male sex change and in inhibiting type-A spermatogonia-like cell proliferation/differentiation during the reversible male-to-female sex change. We suggest that Amh signaling might play dual roles during bi-directional sex change in grouper.

Molecular cloning, characterization, and expression analysis of an ecdysone receptor homolog in Teleogryllus emma (Orthoptera: Gryllidae).

PubMed

He, Hui; Xi, Gengsi; Lu, Xiao

2015-01-01

Ecdysteroids are steroid hormones that play important roles in the regulation of Arthropoda animal growth development, larvae ecdysis, and reproduction. The effect of ecdysteroids is mediated by ecdysteroid receptor (EcR). The ecdysone receptor (EcR) belongs to the superfamily of nuclear receptors (NRs) that are ligand-dependent transcription factors. Ecdysone receptor is present only in invertebrates and plays a critical role in regulating the expression of a series of genes during development and reproduction. Here, we isolated and characterized cDNA of the cricket Teleopgryllus emma (Ohmachi & Matsuura) (Orthoptera: Gryllidae) and studied mRNA expression pattern using real time-polymerase chain reaction. The full-length cDNA of T. emma EcR, termed TeEcR, is 2,558 bp and contains a 5'-untranslated region of 555 bp and a 3'-untranslated region of 407 bp. The open reading frame of TeEcR encodes deduced 531-amino acid peptides with a predicted molecular mass of 60.7 kDa. The amino acid sequence of T. emma EcR was similar to that of known EcR especially in the ligand-binding domain of insect EcR. Real-time quantitative reverse transcription-polymerase chain reaction was performed to compare TeEcR mRNA expression level at the whole body and gonad during T. emma development. The data revealed that TeEcR mRNA is differentially expressed during T. emma development, with the highest expression level in late-instar larvae of the body and lowest in third instar. The levels of TeEcR transcripts also vary among gonads development, and levels in ovaries were higher than in testes at every developmental stage. These results suggest that TeEcR may have potential significance to regulate the morphological structure and gonad development of T. emma, due to its expression in different developmental periods. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Molecular Cloning, Characterization, and Expression Analysis of an Ecdysone Receptor Homolog in Teleogryllus emma (Orthoptera: Gryllidae)

PubMed Central

He, Hui; Xi, Gengsi; Lu, Xiao

2015-01-01

Ecdysteroids are steroid hormones that play important roles in the regulation of Arthropoda animal growth development, larvae ecdysis, and reproduction. The effect of ecdysteroids is mediated by ecdysteroid receptor (EcR). The ecdysone receptor (EcR) belongs to the superfamily of nuclear receptors (NRs) that are ligand-dependent transcription factors. Ecdysone receptor is present only in invertebrates and plays a critical role in regulating the expression of a series of genes during development and reproduction. Here, we isolated and characterized cDNA of the cricket Teleopgryllus emma (Ohmachi & Matsuura) (Orthoptera: Gryllidae) and studied mRNA expression pattern using real time-polymerase chain reaction. The full-length cDNA of T. emma EcR, termed TeEcR, is 2,558 bp and contains a 5′-untranslated region of 555 bp and a 3′-untranslated region of 407 bp. The open reading frame of TeEcR encodes deduced 531-amino acid peptides with a predicted molecular mass of 60.7 kDa. The amino acid sequence of T. emma EcR was similar to that of known EcR especially in the ligand-binding domain of insect EcR. Real-time quantitative reverse transcription-polymerase chain reaction was performed to compare TeEcR mRNA expression level at the whole body and gonad during T. emma development. The data revealed that TeEcR mRNA is differentially expressed during T. emma development, with the highest expression level in late-instar larvae of the body and lowest in third instar. The levels of TeEcR transcripts also vary among gonads development, and levels in ovaries were higher than in testes at every developmental stage. These results suggest that TeEcR may have potential significance to regulate the morphological structure and gonad development of T. emma, due to its expression in different developmental periods. PMID:25797799

Expression of putative sex-determining genes during the thermosensitive period of gonad development in the snapping turtle, Chelydra serpentina.

PubMed

Rhen, T; Metzger, K; Schroeder, A; Woodward, R

2007-01-01

Modes of sex determination are quite variable in vertebrates. The developmental decision to form a testis or an ovary can be influenced by one gene, several genes, environmental variables, or a combination of these factors. Nevertheless, certain morphogenetic aspects of sex determination appear to be conserved in amniotes. Here we clone fragments of nine candidate sex-determining genes from the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination (TSD). We then analyze expression of these genes during the thermosensitive period of gonad development. In particular, we compare gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature. Expression of Dmrt1 and Sox9 mRNA increased gradually at the male-producing temperature, but was suppressed at the female-producing temperature. This finding suggests that Dmrt1 and Sox9 play a role in testis development. In contrast, expression of aromatase, androgen receptor (Ar), and Foxl2 mRNA was constant at the male-producing temperature, but increased several-fold in embryos at the female-producing temperature. Aromatase, Ar, and Foxl2 may therefore play a role in ovary development. In addition, there was a small temperature effect on ER alpha expression with lower mRNA levels found in embryos at the female-producing temperature. Finally, Dax1, Fgf9, and SF-1 were not differentially expressed during the sex-determining period, suggesting these genes are not involved in sex determination in the snapping turtle. Comparison of gene expression profiles among amniotes indicates that Dmrt1 and Sox9 are part of a core testis-determining pathway and that Ar, aromatase, ER alpha, and Foxl2 are part of a core ovary-determining pathway. 2007 S. Karger AG, Basel

Expression profile of amh/Amh during bi-directional sex change in the protogynous orange-spotted grouper Epinephelus coioides

PubMed Central

Wu, Guan-Chung; Li, Hau-Wen; Tey, Wei-Guan; Lin, Chien-Ju; Chang, Ching-Fong

2017-01-01

Gonadal differentiation is tightly regulated by the initial sex determining gene and the downstream sex-related genes in vertebrates. However, sex change in fish can alter the sexual fate from one sex to the other. Chemical-induced maleness in the protogynous orange-spotted grouper is transient, and a reversible sex change occurs after the chemical treatment is withdrawn. We used these characteristics to study Amh signaling during bi-directional sex change in the grouper. We successfully induced the female-to-male sex change by chemical (aromatase inhibitor, AI, or methyltestosterone, MT) treatment. A dormant gonad (a low proliferation rate of early germ cells and no characteristics of both sexes) was found during the transient phase of reversible male-to-female sex change after the withdrawal of chemical administration. Our results showed that amh (anti-mullerian hormone) and its receptor amhr2 (anti-mullerian hormone receptor type 2) were significantly increased in the gonads during the process of female-to-male sex change. Amh is expressed in the Sertoli cells surrounding the type A spermatogonia in the female-to-male grouper. Male-related gene (dmrt1 and sox9) expression was immediately decreased in MT-terminated males during the reversible male-to-female sex change. However, Amh expression was found in the surrounding cells of type A spermatogonia-like cells during the transient phase of reversible male-to-female sex change. This phenomenon is correlated with the dormancy of type A spermatogonia-like cells. Thus, Amh signaling is suggested to play roles in regulating male differentiation during the female-to-male sex change and in inhibiting type-A spermatogonia-like cell proliferation/differentiation during the reversible male-to-female sex change. We suggest that Amh signaling might play dual roles during bi-directional sex change in grouper. PMID:29016690

The importance of having two X chromosomes

PubMed Central

Arnold, Arthur P.; Reue, Karen; Eghbali, Mansoureh; Vilain, Eric; Chen, Xuqi; Ghahramani, Negar; Itoh, Yuichiro; Li, Jingyuan; Link, Jenny C.; Ngun, Tuck; Williams-Burris, Shayna M.

2016-01-01

Historically, it was thought that the number of X chromosomes plays little role in causing sex differences in traits. Recently, selected mouse models have been used increasingly to compare mice with the same type of gonad but with one versus two copies of the X chromosome. Study of these models demonstrates that mice with one X chromosome can be strikingly different from those with two X chromosomes, when the differences are not attributable to confounding group differences in gonadal hormones. The number of X chromosomes affects adiposity and metabolic disease, cardiovascular ischaemia/reperfusion injury and behaviour. The effects of X chromosome number are likely the result of inherent differences in expression of X genes that escape inactivation, and are therefore expressed from both X chromosomes in XX mice, resulting in a higher level of expression when two X chromosomes are present. The effects of X chromosome number contribute to sex differences in disease phenotypes, and may explain some features of X chromosome aneuploidies such as in Turner and Klinefelter syndromes. PMID:26833834

Expression profile analysis of aorta-gonad-mesonephros region-derived stromal cells reveals genes that regulate hematopoiesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagao, Kenji; Ohta, Takayuki; Hinohara, Atsushi

The aorta-gonad-mesonephros (AGM) region is involved in the generation and maintenance of the first definitive hematopoietic stem cells (HSCs). A mouse AGM-derived cell line, AGM-S3, was shown to support the development of HSCs. To elucidate the molecular mechanisms regulating early hematopoiesis, we obtained subclones from AGM-S3, one of which was hematopoiesis supportive (S3-A9) and the other one of which was non-supportive (S3-A7), and we analyzed their gene expression profiles by gene chip analysis. In the present study, we found that Glypican-1 (GPC1) was highly expressed in the supportive subclone AGM-S3-A9. Over-expression of GPC1 in non-supportive cells led to the proliferationmore » of progenitor cells in human cord blood when cocultured with the transfected-stromal cells. Thus, GPC1 may have an important role in the establishment of a microenvironment that supports early events in hematopoiesis.« less

Hormonal Regulation of Extinction: Implication for Mechanisms of Gender Difference in PTSD

DTIC Science & Technology

2009-09-01

role of gonadal hormones in the regulation of Pavlovian fear conditioning and its extinction. Pavlovian fear conditioning and its extinction serve...learning in Pavlovian fear conditioning involves training with the presentation of an innocuous stimulus (the conditioned stimulus – CS) that is associated...GD, Schlinger BA, Fanselow MS (1998) Testicular hormones do not regulate sexually dimorphic Pavlovian fear conditioning or perforant- path long-term

Prolonged treatment with N-acetylcysteine and L-arginine restores gonadal function in patients with polycystic ovary syndrome.

PubMed

Masha, A; Manieri, C; Dinatale, S; Bruno, G A; Ghigo, E; Martina, V

2009-12-01

Nitric oxide (NO) plays a wide spectrum of biological actions including a positive role in oocyte maturation and ovulation. Free radicals levels have been shown elevated in polycystic ovary syndrome (PCOS) and therefore would be responsible for quenching NO that, in turn, would play a role in determining oligo- or amenorrhea connoting PCOS. Eight patients with PCOS displaying oligo-amenorrhea from at least 1 yr underwent a combined treatment with N-acetylcysteine (NAC) (1200 mg/die) plus L-arginine (ARG) (1600 mg/die) for 6 months. Menstrual function, glucose and insulin levels, and, in turn, homeostasis model assessment (HOMA) index were monitored. Menstrual function was at some extent restored as indicated by the number of uterine bleedings under treatment (3.00, 0.18-5.83 vs 0.00, 0.00-0.83; p<0.02). Also, a well-defined biphasic pattern in the basal body temperature suggested ovulatory cycles. The HOMA index decreased under treatment (2.12, 1.46-4.42 vs 3.48, 1.62-5.95; p<0.05). In conclusion, this preliminary, open study suggests that prolonged treatment with NAC+ARG might restore gonadal function in PCOS. This effect seems associated to an improvement in insulin sensitivity.

The effect of a low essential fatty acid diet on hibernation in marmots.

PubMed

Florant, G L; Hester, L; Ameenuddin, S; Rintoul, D A

1993-04-01

We investigated the effect of an essential fatty acid (EFA)-deficient diet on hibernation patterns in yellow-bellied marmots (Marmota flaviventris). Fatty acid (FA) analysis of white adipose tissue (WAT) from animals maintained for 2 mo on the EFA-deficient diet suggested that little or no EFAs were present in the gonadal or omental fat depots. Hibernation about lengths of the EFA-deficient animals were significantly shorter (P < 0.01) than control animals. Stated another way, these animals aroused twice as frequently compared with control animals and used more energy to survive winter. Analysis of WAT composition and blood samples revealed that animals were highly lipolytic during winter. Furthermore, the release of FAs was not random: linoleate (cis-9,cis-12-octadecadienoic acid; 18:2, a diene EFA) was significantly (P < 0.05) under-represented in venous outflow from the gonadal WAT pad based on the percentage of this species in WAT. The concentration of saturated FAs was higher than that predicted from the WAT-FA composition. We conclude that linoleate is preferentially retained within WAT and that concentrations of this EFA may influence hibernation behavior. Thus EFAs may have a thermoregulatory role in hibernation in addition to their role as essential precursors for physiologically important lipids after hibernation is over.

Elucidation of the transcription network governing mammalian sex determination by exploiting strain-specific susceptibility to sex reversal

PubMed Central

Munger, Steven C.; Aylor, David L.; Syed, Haider Ali; Magwene, Paul M.; Threadgill, David W.; Capel, Blanche

2009-01-01

Despite the identification of some key genes that regulate sex determination, most cases of disorders of sexual development remain unexplained. Evidence suggests that the sexual fate decision in the developing gonad depends on a complex network of interacting factors that converge on a critical threshold. To elucidate the transcriptional network underlying sex determination, we took the first expression quantitative trait loci (eQTL) approach in a developing organ. We identified reproducible differences in the transcriptome of the embryonic day 11.5 (E11.5) XY gonad between C57BL/6J (B6) and 129S1/SvImJ (129S1), indicating that the reported sensitivity of B6 to sex reversal is consistent with a higher expression of a female-like transcriptome in B6. Gene expression is highly variable in F2 XY gonads from B6 and 129S1 intercrosses, yet strong correlations emerged. We estimated the F2 coexpression network and predicted roles for genes of unknown function based on their connectivity and position within the network. A genetic analysis of the F2 population detected autosomal regions that control the expression of many sex-related genes, including Sry (sex-determining region of the Y chromosome) and Sox9 (Sry-box containing gene 9), the key regulators of male sex determination. Our results reveal the complex transcription architecture underlying sex determination, and provide a mechanism by which individuals may be sensitized for sex reversal. PMID:19884258

A 46,XX Ovotesticular Disorder of Sex Development Likely Caused by a Steroidogenic Factor-1 (NR5A1) Variant.

PubMed

Swartz, Jonathan M; Ciarlo, Ryan; Guo, Michael H; Abrha, Aser; Weaver, Benjamin; Diamond, David A; Chan, Yee-Ming; Hirschhorn, Joel N

2017-01-01

A variant in steroidogenic factor-1 (SF-1, encoded by the gene NR5A1), p.Arg92Trp, has recently been reported in multiple families with 46,XX ovotesticular or testicular disorders of sex development (DSD). This amino acid change impacts the DNA-binding domain and perturbs gonadal differentiation pathways. Whole-exome sequencing was performed on a 46,XX subject with ovotesticular DSD. Exome results identified a heterozygous NR5A1 variant, p.Arg92Gln, in the 46,XX ovotesticular DSD proband. This arginine-to-glutamine change has been previously reported in the homozygous state in a 46,XY patient with gonadal and adrenal dysgenesis, though 46,XY and 46,XX heterozygous carriers of this variant have not been previously reported to have any clinical phenotype. The NR5A1 p.Arg92Gln variant, which has thus far only been seen in a family with 46,XY DSD, most likely contributes to the ovotesticular DSD in this case. In light of the recent reports of unrelated 46,XX subjects with testicular or ovotesticular DSD with the NR5A1 variant p.Arg92Trp, it appears that other mutations in the DNA binding domain have the potential to impact the factors determining testicular and ovarian differentiation. This case demonstrates the variability of phenotypes with the same genotype and broadens our understanding of the role of SF-1 in gonadal differentiation. © 2016 S. Karger AG, Basel.

Novel Familial Variant of the Desert Hedgehog Gene: Clinical Findings in Two Sisters with 46,XY Gonadal Dysgenesis or 46,XX Karyotype and Literature Review.

PubMed

Baldinotti, Fulvia; Cavallaro, Tiziana; Dati, Eleonora; Baroncelli, Giampiero I; Bertini, Veronica; Valetto, Angelo; Massart, Francesco; Fabrizi, Gian Maria; Zanette, Giampietro; Peroni, Diego; Bertelloni, Silvano

2018-01-01

In humans, Desert Hedgehog (DHH) gene mutations are a very rare cause of 46,XY gonadal dysgenesis (GD), eventually associated with peripheral neuropathy. Clinical records of 12 patients with 46,XY GD and unknown genetic background were reviewed and a 46,XY woman with peripheral neuropathy was individuated. Her 46,XX sister affected by similar neuropathy was also investigated. Genomic DNA was extracted and DHH exons sequenced and analyzed. A comparative genomic hybridization array was also performed. In both the 46,XY and 46,XX sisters, a homozygous c.554C>A mutation in exon 2 of the DHH gene was found, determining a premature termination codon (p.Ser 185*). Heterozygous consanguineous carrier parents showed neither reproductive problems nor peripheral neuropathy. In the proband and her sister, a 499-kb duplication in 9p22.1 was also found. A 46,XY European woman with 46,XY GD and a novel homozygous DHH pathogenic variant is reported, confirming that this gene plays a key role in male gonadal development. Her 46,XX sister, harboring the same mutation, showed normal internal and external female phenotype. Thus, DHH seems not to be involved in the ovarian development pathway or its postpubertal function. Homozygous DHH mutations cause a specific peripheral neuropathy in humans with both 46,XY and 46,XX karyotypes. © 2018 S. Karger AG, Basel.

Testis development requires the repression of Wnt4 by Fgf signaling

PubMed Central

Jameson, Samantha A.; Lin, Yi-Tzu; Capel, Blanche

2013-01-01

The bipotential gonad expresses genes associated with both the male and female pathways. Adoption of the male testicular fate is associated with the repression of many female genes including Wnt4. However, the importance of repression of Wnt4 to the establishment of male development was not previously determined. Deletion of either Fgf9 or Fgfr2 in an XY gonad resulted in up-regulation of Wnt4 and male-to-female sex reversal. We investigated whether the deletion if Wnt4 could rescue sex reversal in Fgf9 and Fgfr2 mutants. XY Fgf9/Wnt4 and Fgfr2/Wnt4 double mutants developed testes with male somatic and germ cells present, suggesting that the primary role of Fgf signaling is the repression of female-promoting genes. Thus, the decision to adopt the male fate is based not only on whether male genes, such as Sox9, are expressed, but also on the active repression of female genes, such as Wnt4. Because loss of Wnt4 results in the up-regulation of Fgf9, we also tested the possibility that derepression of Fgf9 was responsible for the aspects of male development observed in XX Wnt4 mutants. However, we found that the relationship between these two signaling factors is not symmetric: loss of Fgf9 in XX Wnt4−/− gonads does not rescue their partial female-to-male sex-reversal. PMID:22705479

Contextual amplification or attenuation of pubertal timing effects on depressive symptoms among Mexican American girls.

PubMed

White, Rebecca M B; Deardorff, Julianna; Gonzales, Nancy A

2012-06-01

To examine the role of neighborhood contextual variation in the putative association between pubertal timing and depressive symptoms among Mexican-origin girls. Mexican-origin girls (N = 344; x̄(age) = 10.8 years) self-reported their total pubertal, adrenal, and gonadal events, along with levels of depressive symptoms in the 5th grade. Girls' residential addresses were geocoded into neighborhoods, and census data were obtained to describe neighborhoods along two dimensions: Hispanic cultural context and socioeconomic disadvantage. Two years later, when most of the girls were in the 7th grade, we reassessed the girls regarding depressive symptoms. Neighborhood Hispanic composition and neighborhood disadvantage were highly positively correlated. Using hierarchical linear modeling, we examined the moderating influence of neighborhood Hispanic composition and neighborhood disadvantage on the prospective associations between pubertal timing (total, gonadal, and adrenal) and depressive symptoms. Neighborhood Hispanic composition moderated the prospective association between total pubertal and gonadal timing and depressive symptoms. Neighborhood disadvantage did not moderate these associations. Our results suggest that early maturing 5th grade Mexican-origin girls living in non-Hispanic neighborhoods are at the greatest risk for increased depressive symptoms in the 7th grade, even though these neighborhoods tend to be socioeconomically more advantaged. The protective cultural context of largely Hispanic neighborhoods may outweigh the potential amplifying effects of neighborhood disadvantage. Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Response to gonadotropin-releasing hormone challenge: Seasonal variation in steroid production in a viviparous lizard, Tiliqua nigrolutea.

PubMed

Edwards, Ashley; Jones, Susan M

2017-04-01

The hypothalamic-pituitary-gonadal axis plays a central role in the regulation of gamete maturation, sex steroid production and the stimulation of reproductive behaviours in vertebrates. In seasonal breeders, the timely activation and deactivation of this control system is important to ensure successful reproduction: this process is not well understood in species which breed irregularly. Males of the viviparous blotched blue-tongued lizard, Tiliqua nigrolutea, breed annually, while females display a multiennial cycle. We investigated seasonal variation in hypothalamic-pituitary-gonadal axis responsiveness in both sexes of T. nigrolutea. We measured changes in plasma concentrations of testosterone and estrogen in response to a single intraperitoneal injection of a GnRH agonist, chicken-II LH-RH, at three reproductively distinct times of year. Plasma testosterone concentrations in males were significantly increased during gonadal quiescence, but not initial or final spermatogenesis. There was no estrogen response in males at any time of year. Conversely, in females, there was an increase in plasma testosterone, but not estrogen, concentration, in reproductively quiescent females several months in advance of a successful pregnancy. These results indicate clear variation in HPG axis activity with sex, season and reproductive condition in this seasonally breeding viviparous lizard. This study opens the way for further investigation into the mechanisms by which internal (body condition) and external seasonal cues (temperature and photoperiod) are coordinated to regulate reproduction in irregularly-breeding reptiles. Copyright © 2015 Elsevier Inc. All rights reserved.

Adrenocorticotropic Hormone Suppresses Gonadotropin-Stimulated Estradiol Release from Zebrafish Ovarian Follicles

PubMed Central

Alsop, Derek; Ings, Jennifer S.; Vijayan, Mathilakath M.

2009-01-01

While stress is known to impact reproductive performance, the pathways involved are not entirely understood. Corticosteroid effects on the functioning of the hypothalamus-pituitary-gonadal axis are thought to be a key aspect of stress-mediated reproductive dysfunction. A vital component of the stress response is the pituitary secretion of adrenocorticotropic hormone (ACTH), which binds to the melanocortin 2 receptor (MC2R) in the adrenal glands and activates cortisol biosynthesis. We recently reported MC2R mRNA abundance in fish gonads leading to the hypothesis that ACTH may be directly involved in gonadal steroid modulation. Using zebrafish (Danio rerio) ovarian follicles, we tested the hypothesis that acute ACTH stimulation modulates cortisol and estradiol (E2) secretion. ACTH neither affected cortisol nor unstimulated E2 release from ovarian follicles. However, ACTH suppressed human chorionic gonadotropin (hCG)-stimulated E2 secretion in a dose-related manner, with a maximum decrease of 62% observed at 1 I.U. ACTH mL−1. This effect of ACTH on E2 release was not observed in the presence of either 8-bromo-cAMP or forskolin, suggesting that the mechanism(s) involved in steroid attenuation was upstream of adenylyl cyclase activation. Overall, our results suggest that a stress-induced rise in plasma ACTH levels may initiate a rapid down-regulation of acute stimulated E2 biosynthesis in the zebrafish ovary, underscoring a novel physiological role for this pituitary peptide in modulating reproductive activity. PMID:19649243

Emergence, Development, and Maturity of the Gonad of Two Species of Chitons “Sea Cockroach” (Mollusca: Polyplacophora) through the Early Life Stages

PubMed Central

Avila-Poveda, Omar Hernando; Abadia-Chanona, Quetzalli Yasú

2013-01-01

This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or “early life stages” were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aXb. A total of 125 chitons (4≤TL≤40 mm, in total length “TL”) were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods (“Pw” without gonad, “Pe” gonad emergence, and “Pf” gonadal sac formed) and four stages (“S0” gametocytogenesis, “S1” gametogenesis, “S2” mature, and “S3” spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13–14.32 mm, Pe 10.32–16.93 mm, Pf 12.99–25.01 mm, S0 16.08–24.34 mm (females) and 19.51–26.60 mm (males), S1 27.15–35.63 mm (females) and 23.45–32.27 mm (males), S2 24.48–40.24 mm (females) and 25.45–32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management. PMID:23936353

Characterization of Atrazine-Induced Gonadal Malformations in African Clawed Frogs (Xenopus laevis) and Comparisons with Effects of an Androgen Antagonist (Cyproterone Acetate) and Exogenous Estrogen (17β-Estradiol): Support for the Demasculinization/Feminization Hypothesis

PubMed Central

Hayes, Tyrone B.; Stuart, A. Ali; Mendoza, Magdalena; Collins, Atif; Noriega, Nigel; Vonk, Aaron; Johnston, Gwynne; Liu, Roger; Kpodzo, Dzifa

2006-01-01

Atrazine is a potent endocrine disruptor that both chemically castrates and feminizes male amphibians. It depletes androgens in adult frogs and reduces androgen-dependent growth of the larynx in developing male larvae. It also disrupts normal gonadal development and feminizes the gonads of developing males. Gonadal malformations induced by atrazine include hermaphrodites and males with multiple testes [single sex polygonadism (SSP)], and effects occur at concentrations as low as 0.1 ppb (μg/L). Here, we describe the frequencies at which these malformations occur and compare them with morphologies induced by the estrogen, 17β-estradiol (E2), and the antiandrogen cyproterone acetate, as a first step in testing the hypothesis that the effects of atrazine are a combination of demasculinization and feminization. The various forms of hermaphroditism did not occur in controls. Nonpigmented ovaries, which occurred at relatively high frequencies in atrazine-treated larvae, were found in four individuals out of more than 400 controls examined (1%). Further, we show that several types of gonadal malformations (SSP and three forms of hermaphroditism) are produced by E2 exposure during gonadal differentiation, whereas a final morphology (nonpigmented ovaries) appears to be the result of chemical castration (disruption of androgen synthesis and/or activity) by atrazine. These experimental findings suggest that atrazine-induced gonadal malformations result from the depletion of androgens and production of estrogens, perhaps subsequent to the induction of aromatase by atrazine, a mechanism established in fish, amphibians, reptiles, and mammals (rodents and humans). PMID:16818259

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.

Telomeric fusion and chromosome instability in multiple tissues of a patient with mosaic Ullrich-Turner syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawyer, J.R.; North, P.E.; Hassed, S.J.

1997-04-14

We describe the cytogenetic evolution of multiple cell lines in the gonadal tissue of a 10-year-old girl with mosaic Ullrich-Turner syndrome (UTS) involving clonal telomeric associations (tas) of the Y chromosome. G-band analysis of all tissues showed at least 2 cell lines; 45,X and 46,X,tas(Y;21)(q12;p13). However, analysis of left gonadal tissue of this patient showed the evolution of 2 additional cell lines, one designated 45,X,tas(Y;21)(q12;p13),-22 and the other 46,X,tas(Y;21)(q12;p13),+tas(Y;14)(q12;p13),-22. Fluorescence in situ hybridization (FISH) analysis of interphase nuclei from uncultured gonadal tissue confirmed the findings of aneuploidy in the left gonadal tissue and extended the findings of aneuploidy to themore » tissue of the right gonad. The chromosome findings in the gonadal tissue of this patient suggest a preneoplastic karyotype relating to several distinct tumor associations. The clonal evolution of telomeric fusions indicates chromosome instability and suggests the extra copy of the Y chromosome may have resulted from a fusion-related malsegregation. In addition, the extra Y suggests low-level amplification of a putative gonadoblastoma gene, while the loss of chromosome 22 suggests the loss of heterozygosity for genes on chromosome 22. This case demonstrates the utility of the study of gonadal tissue in 45X46,XY UTS patients, and provides evidence that clonal telomeric fusions may, in rare cases, be associated with chromosomal malsegregation and with the subsequent evolution of unstable karyotypes. 27 refs., 3 figs.« less

Scattered dose to gonads and associated risks from radiotherapy for common pediatric malignancies : a phantom study.

PubMed

Mazonakis, Michalis; Zacharopoulou, Fotini; Kachris, Stefanos; Varveris, Charalambos; Damilakis, John; Gourtsoyiannis, Nicholas

2007-06-01

To measure the scattered dose to ovaries and testes from radiotherapy for common pediatric malignancies and to assess the relevant risks for radiation-induced gonadal damage and hereditary disorders in future generations. Radiotherapy for central nervous system tumors, acute leukemia, neuroblastoma, Hodgkin's disease, Wilms' tumor, and sarcoma was simulated on three humanoid phantoms representing patients of 5, 10, and 15 years of age. Ovarian and testicular dose measurements were performed using thermoluminescent dosimeters on a linear accelerator with multileaf collimator (MLC) producing 6-MV X-rays. The effect of lead block introduction into the primary beam on the gonadal dose was evaluated. Gonadal dose from radiotherapy for abdominal tumors was measured using an 18-MV photon beam. For a tumor dose range of 12-55 Gy, the scattered dose to ovaries was 0.5-62.4 cGy depending upon the patient's age (corresponding phantom) and treatment site. The corresponding dose to testes was 0.4-145.0 cGy. The use of blocks for field shaping can increase the gonadal dose up to a factor of 2.0 compared to that measured using MLC. Abdominal irradiation with 18-MV instead of 6-MV X-rays reduced the gonadal dose by more than 1.3 times. For female and male patients, the risk for induction of hereditary disorders was less than 81 x 10(-4) and 188 x 10(-4), respectively. The present dosimetric data suggest that pediatric radiotherapy is not associated with a risk for permanent damage to gonads excluded from the treatment volume. The risk for development of hereditary disorders in offspring conceived after exposure is low.

Effect of Diets Supplemented with Different Sources of Astaxanthin on the Gonad of the Sea Urchin Anthocidaris crassispina

PubMed Central

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

2012-01-01

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. PMID:23016124

Toxic effects of male Perna viridis gonad exposed to BaP, DDT and their mixture: A metabolomic and proteomic study of the underlying mechanism.

PubMed

Song, Qinqin; Zheng, Pengfei; Qiu, Liguo; Jiang, Xiu; Zhao, Hongwei; Zhou, Hailong; Han, Qian; Diao, Xiaoping

2016-01-05

Benzo(a)pyrene and dichlorodiphenyltrichloroethane are typical persistent organic pollutants, and also the widespread environmental estrogens with known toxicity towards green mussels Perna viridis. In this study, the toxicological effects of BaP and DDT and their mixture were assessed in green mussel gonads using proteomic and metabolomic approaches. Metabolomics by NMR spectroscopy revealed that BaP did not show obvious metabolite changes in the gonad of male green mussel. DDT mainly caused some disturbance of osmotic regulation and energy metabolism by changing BCAAs, alanine, threonine, arginine, etc., unknown metabolite (3.53 ppm), glycine, homarine and ATP at different levels. However, the mixture of BaP and DDT mainly caused some disturbance in osmotic regulation and energy metabolism by differentially altering branched chain amino acids, glutamate, alanine, arginine, unknown metabolite (3.53 ppm), glycine, 4-aminobutyrate, dimethylglycine, homarine and ATP. The results suggest that DDT alone may cause most of metabolites changes in the mixture exposed male mussel gonad, and the results also show that the male P. viridis gonad was more sensitive to DDT than BaP exposures. Proteomic study showed that BaP, DDT and their mixture may have different modes of action. Proteomic responses revealed that BaP induced signal transduction, oxidative stress, spermatogenesis, etc. in the male green mussel gonad; whereas DDT exposure altered proteins that were associated with signal transduction, oxidative stress, cytoskeleton and cell structure, cellular organization, energy metabolism, etc. However, the mixture of BaP and DDT affected proteins related to cytoskeleton and cell structure, oxidative stress, cellular organization, etc. This research demonstrated that metabolomic and proteomic approaches could better elucidate the underlying mechanism of environmental pollutants gonad toxicity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Transfer and detection of freshly isolated or cultured chicken (Gallus gallus) and exotic species' embryonic gonadal germ stem cells in host embryos.

PubMed

Imus, Nastassja; Roe, Mandi; Charter, Suellen; Durrant, Barbara; Jensen, Thomas

2014-06-01

The management of captive avian breeding programs increasingly utilizes various artificial reproductive technologies, including in ovo sexing of embryos to adjust population sex ratios. Currently, however, no attention has been given to the loss of genetic diversity following sex-selective incubation, even with respect to individuals from critically endangered species. This project evaluated the possibility of using xenotransfer of embryonic gonadal germline stem cells (GGCs) for future reintroduction of their germplasm into the gene pool. We examined and compared the host gonad colonization of freshly isolated and 3 day (3d) cultured donor GGCs from chicken and 13 species of exotic embryos. Following 3d-culture of GGCs, there was a significant increase in the percentage of stem cell marker (SSEA-1, -3, -4) positive cells. However, the percentage of positive host gonads with chicken donor-derived cells decreased from 68% (fresh) to 22% (3d), while the percentage of exotic species donor-cells positive host gonads decreased from 61% (fresh) to 49% (3d-cultured). Donor GGCs from both chicken and exotic species were localized within the caudal endoderm, including the region encompassing the gonadal ridge by 16 hours post-injection. Furthermore, donor-derived cells isolated from stage 36 host embryos were antigenic for anti SSEA-1, VASA/DDX4 and EMA-1 antibodies, presumably indicating maintenance of stem cell identity. This study demonstrates that GGCs from multiple species can migrate to the gonadal region and maintain presumed stemness following xenotransfer into a chicken host embryo, suggesting that germline stem cell migration is highly conserved in birds.

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. Published by Elsevier Inc.

[Gonad protective effect of radiation protective apron in chest radiography].

PubMed

Hashimoto, Masatoshi; Kato, Hideyuki; Fujibuchi, Toshiou; Ochi, Shigehiro; Morita, Fuminori

2004-12-01

Depending on the facility, a radiation protective apron (protector) is used to protect the gonad from radiation exposure in chest radiography. To determine the necessity of using a protector during chest radiography, we measured the effect of the protector on the gonad in this study. First, using a human body phantom, we measured the absorbed dose of the female gonad with and without the protector, using a thermoluminescence dosimeter (TLD), and confirmed its protective effect. Using the protector, the absorbed dose was reduced to 28+/-2% and 39+/-4% for field sizes of 14 x 17 inch and 14 x 14 inch, respectively. Next, we used Monte Carlo simulation and confirmed, not only the validity of the actual measurement values, but also the fact that the influence of radiation on the absorbed dose of the gonad was mostly from scattered radiation from inside the body for the 14 x 17 inch field size, and also from the X-ray tube for the 14 x 14 inch field size. Although a certain protective effect is achieved by using the protector, the radiation dose to the gonad is only a few microGy even without a protector. Thus, the risk of a genetic effect would be as small as 10(-8). Given that acceptable risk is below 10(-6), we conclude the use of a radiation protective apron is not necessary for diagnostic chest radiography.

Use of gene expression data to determine effects on gonad phenotype in Japanese medaka after exposure to trenbolone or estradiol.

PubMed

Flynn, Kevin; Swintek, Joe; Johnson, Rodney

2013-06-01

Various aquatic bioassays using one of several fish species have been developed or are in the process of being developed by organizations like the US Environmental Protection Agency and the Office of Economic Cooperation and Development for testing potential endocrine-disrupting chemicals (EDCs). Often, these involve assessment of the gonad phenotype of individuals as a key endpoint that is inputted into a risk or hazard assessment. Typically, gonad phenotype is determined histologically, which involves specialized and time-consuming techniques. The methods detailed here utilize an entirely different methodology, reverse-transcription quantitative polymerase chain reaction, to determine the relative expression levels of 4 genes after exposure to either 17β-estradiol or 17β-trenbolone and, by extension, the effects of EDCs on the phenotypic status of the gonad. The 4 genes quantified, Sox9b, protamine, Fig1α, and ZPC1, are all involved in gonad development and maintenance in Japanese medaka (Oryzias latipes); these data were then inputted into a permutational multivariate analysis of variance to determine whether significant differences exist between treatment groups. This information in conjunction with the sexual genotype, which can be determined in medaka, can be used to determine adverse effects of exposure to EDCs in a similar fashion to the histologically determined gonad phenotype. Copyright © 2013 SETAC.

Identification of furan fatty acids in the lipids of common carp (Cyprinus carpio L.).

PubMed

Chvalová, Daniela; Špička, Jiří

2016-06-01

Fatty acid (FA) composition was analyzed in muscle and gonad tissues of marketed common carp (Cyprinus carpio). The extracted lipids were separated into four fractions: polar lipids (PL), diacylglycerols, free fatty acids and triacylglycerols (TAG) using thin layer chromatography. FA content within the lipid fractions was determined by gas chromatography with flame ionization detector (GC/FID). The muscle lipids consisted primarily of TAG (96.9% of total FA), while PL were the major component of both male (67.6%) and female gonad (58.6%) lipids. Polyunsaturated fatty acids predominated in PL of all tissues (52.2-55.8% of total FA); monounsaturated fatty acids were the most abundant FA group in TAG of muscle (51.8%) and female gonads (47.8%) whereas high proportion of furan fatty acids (F-acids) (38.2%) was detected in TAG of male gonads. Eight F-acids were identified by gas chromatography-mass spectrometry (GC/MS) in male gonad samples, including less common 12,15-epoxy-13,14-dimethylnonadeca-12,14-dienoic acid with even-numbered alkyl moiety. Copyright © 2016 Elsevier Ltd. All rights reserved.

A new gonad-infecting species of Philometra (Nematoda: Philometridae) from the Atlantic Spanish mackerel Scomberomorus maculatus (Scombridae) off the Atlantic Coast of Florida and South Carolina.

PubMed

Moravec, František; Bakenhaster, Micah; de Buron, Isaure

2013-04-01

A new nematode species, Philometra atlantica n. sp. (Philometridae), is described from male and female specimens found in the ovary of the Atlantic Spanish mackerel, Scomberomorus maculatus (Mitchill) (Scombridae, Perciformes), off the Atlantic coast of Florida and South Carolina. Based on light and scanning electron microscopy examination, the new species differs from most other gonad-infecting Philometra spp. in the length of spicules (111-126 μm), number and arrangement of genital papillae, and a U-shaped, dorsally interrupted caudal mound in the male. A unique feature among all gonad-infecting philometrids is the presence of 2 reflexed dorsal barbs on the distal end of the gubernaculum. From a few congeneric, gonad-infecting species with unknown males, it can be distinguished by some morphological and biometrical features found in gravid females (body length, length of first-stage larvae or esophagus, structure of caudal end) and by the host type (fish family) and geographical distribution. Philometra atlantica is the fourth valid gonad-infecting species of Philometra reported from fishes of the family Scombridae.

Phenotypic effects of leptin in an ectotherm: a new tool to study the evolution of life histories and endothermy?

PubMed

Niewiarowski, P H; Balk, M L; Londraville, R L

2000-01-01

Leptin is a hormone that regulates energy expenditure and body mass in mammals, and it has attracted considerable attention because of its potential in treating human obesity. Comprehensive data from both pathological and non-pathological systems strongly support a role for leptin in regulating energy metabolism, in thermoregulation and in regulating the onset of puberty. We report here that daily injections of recombinant murine leptin in fence lizards (Sceloporus undulatus) produce phenotypic effects similar to those observed when leptin injections are given to mice. Lizards injected with leptin had body temperatures 0.6 degrees C higher, ate 30 % less food and showed a 14 % reduction in activity rates, and females showed a 2. 5-fold increase in resting metabolic rates, compared with lizards injected with vehicle only (phosphate-buffered saline). We also detected native lizard leptin using an immunoassay. Our results indicate that leptin is expressed in ectotherms and may be conserved both functionally and structurally. In the wake of unprecedented research activity on the role of leptin as a cause of, and potential treatment for, human obesity, we believe that other applications of leptin research have been ignored. For example, the response of lizards to leptin injection in our study has important implications for two broad areas of research in evolutionary biology: the evolution of age at first reproduction and of endothermy. We argue that research in these areas, previously limited to comparative approaches, may now benefit from experimental manipulations using leptin.

Emerging roles for neurosteroids in sexual behavior and function.

PubMed

King, Steven R

2008-01-01

Although gonadal and adrenal steroids heavily impact sexual function at the level of the brain, the nervous system also produces its own steroids de novo that may regulate sexual behavior and reproduction. Current evidence points to important roles for neurosteroids in sexual and gender-typical behaviors, control of ovulation, and behaviors that strongly influence sexual interest and motivation like aggression, anxiety and depression. At the cellular level, neurosteroids act through stimulating rapid changes in excitability and direct activation of membrane receptors in neurons. Thus, unlike peripheral steroids, neurosteroids can have immediate and specific effects on select neuronal pathways to regulate sexual function.

Comparative biochemical composition in gonad and adductor muscle of triploid and diploid catarina scallop (Argopecten ventricosus Sowerby II, 1842).

PubMed

Ruiz-Verdugo, C A.; Racotta, I S.; Ibarra, A M.

2001-05-15

Biochemical components of gonad and adductor muscle for diploid and triploid catarina scallop, Argopecten ventricosus, were evaluated and compared at four periods in 1 year (January, April, June, and October). Two comparisons were done. The first one compared an untreated control (diploid) vs. a triploidy-treated group for which the percentage of triploids was 57%. The second comparison was done on a group derived from within the triploidy-treated group, separating diploids (internal control) from triploids ('putative triploids'). Regardless of which comparison, in the gonad diploid scallops had larger concentrations of proteins, carbohydrates, lipids, and acylglycerols than triploid scallops. This reflects the maturation processes in diploid scallops vs. the sterility seen in most triploid scallops, and it is particularly supported by the consistently larger concentration of acylglycerols in gonads of diploids than in triploids. The gonad index of the internal control (diploid) group was significantly larger than that seen in the putative triploid group at all sampling periods but October, when none of the gonad biochemical components were different between ploidy groups.Triploid scallops had a significantly larger muscle index than diploids from April to October. This can be caused by a larger gain in muscle tissue in triploids than diploids from January to June. However, there were no consistent differences in any of the biochemical components evaluated in adductor muscle of diploids and triploids. The use of freshly ingested food rather than reserve mobilization from muscle in diploids is suggested by these results. Nutrients derived from ingested food are apparently used for muscle growth in triploids, whereas in diploids those nutrients serve primarily for gonad development. The importance of freshly ingested food for maintenance and growth is suggested because the decline in biochemical components seen in October in both muscle and gonad was paired with a decline in weight of those two organs, especially when the control groups are considered, but a decrease was also evident for the triploid groups. This may have been caused by the presence of El Niño, with its characteristic high water temperatures and low productivity.

Budgerigars (Melopsittacus undulatus) do not hear infrasound: the audiogram from 8 Hz to 10 kHz.

PubMed

Heffner, Henry E; Koay, Gimseong; Heffner, Rickye S

2016-12-01

The pure-tone thresholds of three budgerigars were determined from 8 Hz to 10 kHz. At a level of 60 dB sound pressure level (re 20 μN/m 2 ), their hearing range extends 6.6 octaves from 77 Hz to 7.6 kHz, with a best sensitivity of 1.1 dB at 3 kHz. Unlike pigeons and chickens, budgerigars do not have better low-frequency hearing than humans. This difference implies anatomical, physiological, and ecological differences between birds that hear infrasound (so far, pigeons and chickens) and those that do not (budgerigars).

The Role of the Y-Located TSPY Gene in Prostatic Oncongenesis

DTIC Science & Technology

2006-02-01

Vizantios Y, Freeman R, Sicurella C, Hammett F, Armes J, Venter D. Cyclooxygenase-2, a colorectal cancer nonsteroidal anti - inflammatory drug target, is...antibodies were detected using ap- propriate secondary antibodies (1:4,000 peroxidase conjugated Donkey anti rabbit/Sheep anti mouse [Amersham...known as ( non )dysgerminomas of the ovary and dysgenetic gonad, and ( non )germinomas of the brain. Various risk factors for these types of GCTs have beenary

Endocannabinoids and the Endocrine System in Health and Disease.

PubMed

Hillard, Cecilia J

2015-01-01

Some of the earliest reports of the effects of cannabis consumption on humans were related to endocrine system changes. In this review, the effects of cannabinoids and the role of the CB1 cannabinoid receptor in the regulation of the following endocrine systems are discussed: the hypothalamic-pituitary-gonadal axis, prolactin and oxytocin, thyroid hormone and growth hormone, and the hypothalamic-pituitary-adrenal axis. Preclinical and human study results are presented.

Clinical review of 95 patients with 46,XX disorders of sex development based on the new Chicago classification.

PubMed

Öcal, Gönül; Berberoğlu, Merih; Sıklar, Zeynep; Aycan, Zehra; Hacıhamdioglu, Bülent; Savas Erdeve, Şenay; Çamtosun, Emine; Kocaay, Pınar; Ruhi, Hatice I; Kılıç, Birim G; Tukun, Ajlan

2015-02-01

The aim of our study was to determine the etiologic distribution of 46,XX disorder of sexual development (DSD) according to the new DSD classification system and to evaluate the clinical features of this DSD subgroup in our patient cohort. The evaluation criteria and clinical findings of 95 46,XX patients were described by clinical presentation, gonadal morphology, genital anatomy, associated dysmorphic features, presence during prenatal period with/without postnatal virilization, hormonal characteristics, and presence or absence of steroidogenic defects among 319 patients with DSD. Types and ratios of each presentation of our 95 patients with 46,XX DSD were as follows: 82 had androgen excess (86.3%): (74 had classical congenital adrenal hyperplasia, 2 had CAH variant possibility of P450-oxidoreductase gene defect), 6 had disorders of ovarian development (6.3%): (1 patient had gonadal dysgenesis with virilization at birth with bilateral streak gonad, 4 patients had complete gonadal dysgenesis, and 1 patient had ovotesticular DSD) and 7 had other 46,XX DSD. Two sisters, who had 46,XX complete gonadal dysgenesis,were diagnosed with Perrault Syndrome with ovarian failure due to streak gonads and associated with sensorineural deafness. 46,XX DSD are usually derived from intrauterine virilization and CAH is the most common cause of 46,XX DSD due to fetal androgen exposure. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Effect of cyclophosphamide exposure on the migration of primordial germ cells in rat fetuses.

PubMed

Ray, B; D'Souza, A S; Potu, B K; Saxena, A

2012-01-01

Effect of a single dose of cyclophosphamide on migration of the primordial germ cells (PGC), when they are about to reach gonadal ridge was investigated histochemically by staining for alkaline phosphatase. This may throw some light on the fate of gonadal ridge when exposed to the drug itself or its breakdown products such as acrolein, which is present as an environmental pollutant. Twelve pregnant Charles foster rats were divided in to control and treatment groups and kept in separate cages. In the experimental group, Cyclophosphamide 20 mg/kg/body weight was injected intraperitoneally on day 12 of gestation. Transverse sections of fetuses collected on day 16 of gestation were stained for alkaline phosphatase activity. Outcome of the study was analysed by scanning the photomicrographs and represented by photomicrographs. An unique finding in experimental group in the gonadal ridge consisted of homogeneously distributed pale staining cells. The gonadal ridge-mesonephros junction showed a single big cluster of the PGC. Under higher magnification, the PGC could be identified by oval or circular shape with well-defined cell membranes and very distinct dark brown staining. There were no signs of degeneration or disintegration of these cells. Cyclophosphamide exposure led to failure of PGC to spread inwards from the gonadal ridge-mesonephros junction giving rise to a situation so far not reported in literature. The presented phenomenon will result in improper development of the gonads leading to infertility in an affected individual in future generation (Fig. 4, Ref. 18).

The "yin and yang" of the adrenal and gonadal systems in elite military men.

PubMed

Taylor, Marcus K; Hernández, Lisa M; Kviatkovsky, Shiloah A; Schoenherr, Matthew R; Stone, Michael S; Sargent, Paul

2017-05-01

We recently established daily, free-living profiles of the adrenal hormone cortisol, the (primarily adrenal) anabolic precursor dehydroepiandrosterone (DHEA) and the (primarily gonadal) anabolic hormone testosterone in elite military men. A prevailing view is that adrenal and gonadal systems reciprocally modulate each other; however, recent paradigm shifts prompted the characterization of these systems as parallel, cooperative processes (i.e. the "positive coupling" hypothesis). In this study, we tested the positive coupling hypothesis in 57 elite military men by evaluating associations between adrenal and gonadal biomarkers across the day. Salivary DHEA was moderately and positively coupled with salivary cortisol, as was salivary testosterone. Anabolic processes (i.e. salivary DHEA and testosterone) were also positively and reliably coupled across the day. In multivariate models, salivary DHEA and cortisol combined to account for substantial variance in salivary testosterone concentrations across the day, but this was driven almost exclusively by DHEA. This may reflect choreographed adrenal release of DHEA with testicular and/or adrenal release of testosterone, systemic conversion of DHEA to testosterone, or both. DHEA and testosterone modestly and less robustly predicted cortisol concentrations; this was confined to the morning, and testosterone was the primary predictor. Altogether, top-down co-activation of adrenal and gonadal hormone secretion may complement bottom-up counter-regulatory functions to foster anabolic balance and neuronal survival; hence, the "yin and yang" of adrenal and gonadal systems. This may be an adaptive process that is amplified by stress, competition, and/or dominance hierarchy.

A Honey Bee Hexamerin, HEX 70a, Is Likely to Play an Intranuclear Role in Developing and Mature Ovarioles and Testioles

PubMed Central

Martins, Juliana R.; Anhezini, Lucas; Dallacqua, Rodrigo P.; Simões, Zilá L. P.; Bitondi, Márcia M. G.

2011-01-01

Insect hexamerins have long been known as storage proteins that are massively synthesized by the larval fat body and secreted into hemolymph. Following the larval-to-pupal molt, hexamerins are sequestered by the fat body via receptor-mediated endocytosis, broken up, and used as amino acid resources for metamorphosis. In the honey bee, the transcript and protein subunit of a hexamerin, HEX 70a, were also detected in ovaries and testes. Aiming to identify the subcellular localization of HEX 70a in the female and male gonads, we used a specific antibody in whole mount preparations of ovaries and testes for analysis by confocal laser-scanning microscopy. Intranuclear HEX 70a foci were evidenced in germ and somatic cells of ovarioles and testioles of pharate-adult workers and drones, suggesting a regulatory or structural role. Following injection of the thymidine analog EdU we observed co-labeling with HEX 70a in ovariole cell nuclei, inferring possible HEX 70a involvement in cell proliferation. Further support to this hypothesis came from an injection of anti-HEX 70a into newly ecdysed queen pupae where it had a negative effect on ovariole thickening. HEX 70a foci were also detected in ovarioles of egg laying queens, particularly in the nuclei of the highly polyploid nurse cells and in proliferating follicle cells. Additional roles for this storage protein are indicated by the detection of nuclear HEX 70a foci in post-meiotic spermatids and spermatozoa. Taken together, these results imply undescribed roles for HEX 70a in the developing gonads of the honey bee and raise the possibility that other hexamerins may also have tissue specific functions. PMID:22205988

A honey bee hexamerin, HEX 70a, is likely to play an intranuclear role in developing and mature ovarioles and testioles.

PubMed

Martins, Juliana R; Anhezini, Lucas; Dallacqua, Rodrigo P; Simões, Zilá L P; Bitondi, Márcia M G

2011-01-01

Insect hexamerins have long been known as storage proteins that are massively synthesized by the larval fat body and secreted into hemolymph. Following the larval-to-pupal molt, hexamerins are sequestered by the fat body via receptor-mediated endocytosis, broken up, and used as amino acid resources for metamorphosis. In the honey bee, the transcript and protein subunit of a hexamerin, HEX 70a, were also detected in ovaries and testes. Aiming to identify the subcellular localization of HEX 70a in the female and male gonads, we used a specific antibody in whole mount preparations of ovaries and testes for analysis by confocal laser-scanning microscopy. Intranuclear HEX 70a foci were evidenced in germ and somatic cells of ovarioles and testioles of pharate-adult workers and drones, suggesting a regulatory or structural role. Following injection of the thymidine analog EdU we observed co-labeling with HEX 70a in ovariole cell nuclei, inferring possible HEX 70a involvement in cell proliferation. Further support to this hypothesis came from an injection of anti-HEX 70a into newly ecdysed queen pupae where it had a negative effect on ovariole thickening. HEX 70a foci were also detected in ovarioles of egg laying queens, particularly in the nuclei of the highly polyploid nurse cells and in proliferating follicle cells. Additional roles for this storage protein are indicated by the detection of nuclear HEX 70a foci in post-meiotic spermatids and spermatozoa. Taken together, these results imply undescribed roles for HEX 70a in the developing gonads of the honey bee and raise the possibility that other hexamerins may also have tissue specific functions.

Emerging roles of NUCB2/nesfatin-1 in the metabolic control of reproduction.

PubMed

García-Galiano, David; Tena-Sempere, Manuel

2013-01-01

Nesfatin-1, derived from the precursor NEFA/nucleobindin2 (NUCB2), was initially identified as a feeding-suppressing neuropeptide, acting at central (mainly, hypothalamic) levels in a leptin-independent manner. However, recent experimental evidence strongly suggests that, rather than being a simple anorectic hypothalamic signal, nesfatin-1 operates at different tissues as an integral regulator of energy homeostasis and closely related neuroendocrine functions. On the latter, growing, albeit as yet fragmentary, evidence has pointed out recently that NUCB2/ nesfatin-1 is involved in the regulation of different aspects of reproductive maturation and function, by acting probably at different levels of the hypothalamic-pituitary-gonadal (HPG) axis. As documented by rodent studies, the reproductive facet of nesfatin-1 likely includes (i) a permissive role in (female) pubertal maturation, (ii) stimulatory effects on the gonadotropic axis, whose magnitude, in terms of LH responses, varies depending on the maturational stage and probably the sex and species, and (iii) direct expression and actions in the gonads. These features, together with the proven expression of NUCB2/nesfatin-1 in tissues with essential roles in the metabolic control of reproduction, such as the hypothalamus, adipose and pancreas, support a putative role of nesfatin-1 as neurohormonal signal linking body metabolic status, puberty and fertility. Curiously enough, although its reproductive dimension seems to be conserved in non-mammalian vertebrates, recent studies in goldfish have surfaced predominant inhibitory actions of nesfatin-1 at different levels of the HPG axis in fish. These findings illustrate our as yet limited understanding of this aspect of nesfatin-1 physiology, whose relevance in the joint control of metabolism and reproduction in health and disease warrants further investigation.

Differential FoxP2 and FoxP1 expression in a vocal learning nucleus of the developing budgerigar

PubMed Central

Whitney, Osceola; Voyles, Tawni; Hara, Erina; Chen, Qianqian; White, Stephanie A.; Wright, Timothy F.

2014-01-01

The forkhead domain FOXP2 and FOXP1 transcription factors are implicated in several cognitive disorders with language deficits, notably autism, and thus play a central role in learned vocal motor behavior in humans. Although a similar role for FoxP2 and FoxP1 is proposed for other vertebrate species, including songbirds, the neurodevelopmental expression of these genes are unknown in a species with lifelong vocal learning abilities. Like humans, budgerigars (Melopsittacus undulatus) learn new vocalizations throughout their entire lifetime. Like songbirds, budgerigars have distinct brain nuclei for vocal learning, which include the magnocellular nucleus of the medial striatum (MMSt), a basal ganglia region that is considered developmentally and functionally analogous to Area X in songbirds. Here we used in situ hybridization and immunohistochemistry to investigate FoxP2 and FoxP1 expression in the MMSt of juvenile and adult budgerigars. We found FoxP2 mRNA and protein expression levels in the MMSt that were lower than the surrounding striatum throughout development and adulthood. In contrast, FoxP1 mRNA and protein had an elevated MMSt/striatum expression ratio as birds matured, regardless of their sex. These results show that life-long vocal plasticity in budgerigars is associated with persistent low-level FoxP2 expression in the budgerigar MMSt, and suggests the possibility that FoxP1 plays an organizational role in the neurodevelopment of vocal motor circuitry. Thus, developmental regulation of the FoxP2 and FoxP1 genes in the basal ganglia appears essential for vocal mimicry in a range of species that possess this relatively rare trait. PMID:25407828

Differential FoxP2 and FoxP1 expression in a vocal learning nucleus of the developing budgerigar.

PubMed

Whitney, Osceola; Voyles, Tawni; Hara, Erina; Chen, Qianqian; White, Stephanie A; Wright, Timothy F

2015-07-01

The forkhead domain FOXP2 and FOXP1 transcription factors are implicated in several cognitive disorders with language deficits, notably autism, and thus play a central role in learned vocal motor behavior in humans. Although a similar role for FoxP2 and FoxP1 is proposed for other vertebrate species, including songbirds, the neurodevelopmental expression of these genes are unknown in a species with lifelong vocal learning abilities. Like humans, budgerigars (Melopsittacus undulatus) learn new vocalizations throughout their entire lifetime. Like songbirds, budgerigars have distinct brain nuclei for vocal learning, which include the magnocellular nucleus of the medial striatum (MMSt), a basal ganglia region that is considered developmentally and functionally analogous to Area X in songbirds. Here, we used in situ hybridization and immunohistochemistry to investigate FoxP2 and FoxP1 expression in the MMSt of juvenile and adult budgerigars. We found FoxP2 mRNA and protein expression levels in the MMSt that were lower than the surrounding striatum throughout development and adulthood. In contrast, FoxP1 mRNA and protein had an elevated MMSt/striatum expression ratio as birds matured, regardless of their sex. These results show that life-long vocal plasticity in budgerigars is associated with persistent low-level FoxP2 expression in the budgerigar MMSt, and suggests the possibility that FoxP1 plays an organizational role in the neurodevelopment of vocal motor circuitry. Thus, developmental regulation of the FoxP2 and FoxP1 genes in the basal ganglia appears essential for vocal mimicry in a range of species that possess this relatively rare trait. © 2014 Wiley Periodicals, Inc.

Therapy Insight: preserving fertility in cyclophosphamide-treated patients with rheumatic disease.

PubMed

Dooley, Mary Anne; Nair, Raj

2008-05-01

Cyclophosphamide remains a necessary treatment for severe rheumatic diseases, despite the continued search for alternative therapies with less gonadal toxicity. The risk of premature gonadal failure and sterility might lead young patients to delay treatment with cyclophosphamide. The patient's age at treatment and the cumulative dose received remain important risk factors for cyclophosphamide-induced gonadal failure in both males and females. Estrogen-containing oral contraceptives for females and testosterone for males are suggested to reduce the gonadal toxicity of cyclophosphamide, although few studies support these interventions. Owing to increased side effects, hormonal therapy is often avoided in patients with edema, hypertension, nephrotic syndrome or antiphospholipid antibodies. Agonists and antagonists of gonadotropin receptors are under study. Gonadotropin-receptor agonists might have beneficial effects in addition to suppression of sex-hormone production. The outcome of attempted cryopreservation of eggs, embryos or ovaries remains uncertain for women seeking to preserve their reproductive potential. Storing male gametes before chemotherapy is widely practiced and technically successful. As recovery of menses or production of testosterone does not predict individual fertility, identification of biomarkers of gonadal function and reserve, including serum levels of several hormones, ultrasonographic measurements of ovarian volume and antral follicle count, are necessary.

[The mixed gonadal dysgenesis. Diagnostic criteria and surgical treatment].

PubMed

Blanco, J A; Martínez-Mora, J; Granada, M; Toran, N; Isnard, R M; Castellví, A; Casasa, J M

1997-01-01

The Mixed Gonadal Dysgenesis represents the 7.6% of all our patients with intersexual states. We report 14 patients who present Mixed Gonadal Dysgenesis. We have studied: diagnosis age; external genitalia description; sex assigned in birth and if has changed; the karyotype; sex chromatine; hormonal study; genitography; internal genitalia and internal Mullerians ducts structures; gonadal histologycal study; surgical treatment and hormonal treatment. The results show that 50% of the cases presents a 46XY karyotype and the other 50% mosaicisme 45XO/46XY. The histological study is very distinctive. A vulvovagynoplasty and clitoroplasty was made in all the cases. Four patients must follow an hormonal treatment after reaching puberal age. Summing up, with patients having ambiguous genitalia we can suspect it consists of a Mixed Gonadal Dysgenesis. The diagnosis must be precocious. And this diagnosis will be based in an ambiguous genitalia, with a karyotype 46XY or 45XO/46XY, the persistence of the internal Müllerian duct structures, and the histological study with a dysgenetic testis. These patients should be raised as females because they can obtain a good morphological and functional development like a normal female.

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.

Relationship between gonad maturation and heavy metal accumulation in the clam, Galatea paradoxa (Born 1778) from the Volta estuary, Ghana.

PubMed

Adjei-Boateng, D; Obirikorang, K A; Amisah, S; Madkour, H A; Otchere, F A

2011-12-01

The relationship between gonadal development and the concentrations of four heavy metals Mn, Zn, Fe and Hg in the tissues of the clam Galatea paradoxa was evaluated at the Volta estuary, Ghana, over an 18-month period. Metal concentrations in the clam tissues were highly variable over the sampling period and seemed to be influenced by the reproductive cycle of the clam. Mn concentrations varied over a wide range from 49 to 867 μg/g and exhibited a significant positive correlation with gonadal development (p = 0.0146, r(2) = 0.3190). Zn and Fe concentrations ranged from 13 to 59 μg/g and 79 to 484 μg/g, respectively and both revealed negative relationships between gonad development and metal accumulation (Zn (p = 0.0554, r(2) = 0.0554) and Fe (p = 0.1040, r(2) = 0.1567)). Hg concentrations ranged from 0.026 to 0.059 μg/g over the sampling period and exhibited a slight positive relationship between gonadal development and metal accumulation (p = 0.0861, r(2) = 0.1730).

[Sexual differentiation of the human brain].

PubMed

Kula, K; Słowikowska-Hilczer, J

2000-01-01

Normal human development requires the compatibility between genetic sex (sex chromosomes), sex of gonades (tests or ovaries), genitalia (external and internal sex organs), somatic features (body characteristics) and psychic sex. The psychic sex, called frequently gender, consist of gender identity (self-estimation), gender role (objective estimation) and sexual orientation (hetero- or homosexual). It was believed that the psychic gender depends only on socio-environmental influences such as rearing, learning and individual choice. Although, the process of sexual differentiation of human brain is not completely elucidated, it has became recently evident that endogenous hormones more then socio-environmental factors influence gender differences. Experimental studies on animals revealed that transient action of sex steroids during perinatal period of life is crucial for the dymorphism of sexual behavior (male or female) in adulthood. It seems, that also in the human male neonates testosterone produced by testes perinatally takes the main role in the irreversible masculinization of the brain i.e. creation of the differences vs. female brain. The evaluation of patients with disturbances of sexual differentiation of external genitalia (the lack of the testosterone transformation into 5-alpha dihydrotestosterone in peripheral tissues of men or the inborn excess of androgens in women with the congenital adrenal hyperplasia) has served as a useful clinical model for understanding factors, affecting the formation of gender. In these individuals the formal sex established according to genetic sex and somatic sex may be incompatible with gender identity and role. However, it has been found that the female gender identity is most frequently associated with the presence of ovaries or the lack of gonads (gonadal dysgenesis), while the male gender identity appear most frequently in the presence of testicular tissue irrespective of female or hermaphrodite (intersex) phenotype. In genetic men with the absence of male genitalia formation, caused by the aberrant function of androgen receptor, the gender identity depends on the severity of the disorder: female gender identity in the complete androgen insensitivity syndrome and female or male gender identity in the complete androgen insensitivity syndrome and female or male in the partial androgen insensitivity. These clinical observations confirm the experimental data indicating androgen role in the male gender identity creation. This knowledge is necessary for the decision of the direction of surgical correction of sex organs in children with ambiguous genitalia, which should not depend on the expected efficiency to perform sexual intercourse, but mostly on the expected or already present individual gender identity.

Ranitidine does not affect gonadal function in man.

PubMed Central

Wang, C; Wong, K L; Lam, K C; Lai, C L

1983-01-01

We studied the effect of ranitidine on gonadal function in 20 male subjects with chronic duodenal ulcer. Eleven were treated with ranitidine 150 mg twice daily for 3 months and 150 mg at night for 9 months, nine with placebo for 3 months. Similar to placebo, treatment with ranitidine did not influence basal serum concentrations of testosterone (T), luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL). No significant changes were found in sperm concentration, motility or morphology. Ranitidine does not affect gonadal function in man. PMID:6313029

Prostaglandins in reproductive physiology*

PubMed Central

Craig, Gillian M.

1975-01-01

The role of prostaglandins in reproductive physiology is reviewed with particular emphasis on their possible importance in ovulation in humans. A possible interaction between gonadal steroids, biogenic amines and prostaglandins at hypothalamic-pituitary level, in relation to the release of luteinizing hormone releasing factor, and LH, is discussed. Anomalies regarding the role of oestrogens in LH release are noted, and it is suggested that high oestrogen levels may release prostaglandins from the uterus and/or centrally in humans, in connection with the mid-cycle LH surge and ovulation. A hypothetical role for prostaglandins in sexual behaviour and premenstrual changes is discussed. The hypotheses open up new areas for clinical research to establish the role of prostaglandins in human endocrinology. The need for measurement of prostaglandin metabolites in blood and urine is emphasized. PMID:1089972

Light colour and intensity alters reproductive/seasonal responses in Japanese quail.

PubMed

Yadav, Suneeta; Chaturvedi, Chandra Mohini

2015-08-01

An extensive literature is available on the photoperiodic responses of avian species but studies on light colour and wavelength from light emitting diode (LED) sources on reproduction are limited. Hence, an experiment was designed to study the effect of different colours and intensities of light on the reproductive responses of Japanese quail. Three-week old quail were exposed to five different light conditions with a long photoperiod (LD 16:8): WT (white fluorescent light 100 lux as control), W LED (white light emitting diode, 30 lux), B LED (blue LED, 30 lux), G LED (green LED, 30 lux) and R-LED (red LED, 30 lux). The cloacal gland size, an indicator of androgenic activity, was monitored weekly. The results indicated an early initiation of gonadal growth in WT quail which continued and maintained a plateau throughout the period of study. On the other hand, in general low intensity light, there was a decreased amplitude of the reproductive cycle and the quail exposed to different colour lights (green, red and blue lights) used different incubation times to initiate their gonadal growth and exhibited a gonadal cycle of a different duration up to 15.5 weeks. Thereafter, the gonad of quail of all the LED groups started developing again (including the blue LED exposed quail which remained undeveloped until this age) and attained the increased degree of growth until 26.5 weeks of age. During the second cycle, gonads of green and red light exposed quail continued to increase and maintained a plateau of development similar to WT exposed control while white and blue LED exposed quail exhibited spontaneous regression and attained complete sexual quiescence. Based on our study, it is suggested that long term exposure to blue LED light of low intensity may induce gonadal regression even under long-day conditions (LD 16:8), while exposure to green and red lights appears to maintain a constant photosensitivity after one complete gonadal cycle. Copyright © 2015 Elsevier Inc. All rights reserved.

Genetic effects of radiotherapy for childhood cancer: gonadal dose reconstruction.

PubMed

Stovall, Marilyn; Donaldson, Sarah S; Weathers, Rita E; Robison, Leslie L; Mertens, Ann C; Winther, Jeanette Falck; Olsen, Jorgen H; Boice, John D

2004-10-01

To estimate the doses of radiation to organs of interest during treatment of childhood cancer for use in an epidemiologic study of possible heritable diseases, including birth defects, chromosomal abnormalities, cancer, stillbirth, and neonatal and premature death. The study population was composed of more than 25,000 patients with cancer in Denmark and the United States who were survivors of childhood cancer and subsequently had nearly 6,500 children of their own. Radiation therapy records were sought for the survivors who parented offspring who had adverse pregnancy outcomes (>300 offspring), and for a sample of all survivors in a case-cohort design. The records were imaged and centrally abstracted. Water phantom measurements were made to estimate doses for a wide range of treatments. Mathematical phantoms were used to apply measured results to estimate doses to ovaries, uterus, testes, and pituitary for patients ranging in age from newborn to 25 years. Gonadal shielding, ovarian pinning (oophoropexy), and field blocking were taken into account. Testicular radiation doses ranged from <1 to 700 cGy (median, 7 cGy) and ovarian doses from <1 to >2,500 cGy (median, 13 cGy). Ten percent of the records were incomplete, but sufficient data were available for broad characterizations of gonadal dose. More than 49% of the gonadal doses were >10 cGy and 16% were >100 cGy. Sufficient radiation therapy data exist as far back as 1943 to enable computation of gonadal doses administered for curative therapy for childhood cancer. The range of gonadal doses is broad, and for many cancer survivors, is high and just below the threshold for infertility. Accordingly, the epidemiologic study has >90% power to detect a 1.3-fold risk of an adverse pregnancy outcome associated with radiation exposure to the gonads. This study should provide important information on the genetic consequences of radiation exposure to humans.

Dissociable Effects of Sry and Sex Chromosome Complement on Activity, Feeding and Anxiety-Related Behaviours in Mice

PubMed Central

Kopsida, Eleni; Lynn, Phoebe M.; Humby, Trevor; Wilkinson, Lawrence S.; Davies, William

2013-01-01

Whilst gonadal hormones can substantially influence sexual differentiation of the brain, recent findings have suggested that sex-linked genes may also directly influence neurodevelopment. Here we used the well-established murine ‘four core genotype’ (FCG) model on a gonadally-intact, outbred genetic background to characterise the contribution of Sry-dependent effects (i.e. those arising from the expression of the Y-linked Sry gene in the brain, or from hormonal sequelae of gonadal Sry expression) and direct effects of sex-linked genes other than Sry (‘sex chromosome complement’ effects) to sexually dimorphic mouse behavioural phenotypes. Over a 24 hour period, XX and XY gonadally female mice (lacking Sry) exhibited greater horizontal locomotor activity and reduced food consumption per unit bodyweight than XX and XY gonadally male mice (possessing Sry); in two behavioural tests (the elevated plus and zero mazes) XX and XY gonadally female mice showed evidence for increased anxiety-related behaviours relative to XX and XY gonadally male mice. Exploratory correlational analyses indicated that these Sry-dependent effects could not be simply explained by brain expression of the gene, nor by circulating testosterone levels. We also noted a sex chromosome complement effect on food (but not water) consumption whereby XY mice consumed more over a 24hr period than XX mice, and a sex chromosome complement effect in a third test of anxiety-related behaviour, the light-dark box. The present data suggest that: i) the male-specific factor Sry may influence activity and feeding behaviours in mice, and ii) dissociable feeding and anxiety-related murine phenotypes may be differentially modulated by Sry and by other sex-linked genes. Our results may have relevance for understanding the molecular underpinnings of sexually dimorphic behavioural phenotypes in healthy men and women, and in individuals with abnormal sex chromosome constitutions. PMID:24009762

Calbindin-D28k immunoreactivity is a marker for a subdivision of the sexually dimorphic nucleus of the preoptic area of the rat: developmental profile and gonadal steroid modulation.

PubMed

Sickel, M J; McCarthy, M M

2000-05-01

Calbindin-D28k (calbindin) is a 28 kilodalton calcium binding protein which potentially plays a role in neuroprotection. We report here the normal development and gonadal steroid modulation of a sexually dimorphic group of calbindin immunoreactive cells within the sexually dimorphic nucleus of the preoptic area (SDN) which we call the calbindin-immunoreactive SDN or CALB-SDN. Beginning on PN2, a faintly immunoreactive CALB-SDN is present, however, the volume is not sexually dimorphic. On PN4, the staining of the CALB-SDN appears more robust but the volume is still not sexually dimorphic. By PN8 and extending through PN12 and PN26, the latest age analysed, the volume of the CALB-SDN is larger in males by two- to fourfold. Cresyl violet counterstain reveals a similar developmental profile of the SDN as well as clusters of darkly staining calbindin immunonegative cells which lie around the CALB-SDN. Castration of males on PN0 decreases the volume of the CALB-SDN by PN12 and administration on the day of birth and PN1 of either testosterone propionate or oestradiol benzoate, but not dihydrotestosterone propionate to females increases the volume of the CALB-SDN by PN12. By demonstrating the sexual dimorphism and gonadal steroid modulation of the CALB-SDN, we hereby establish that calbindin is a specific marker of a subdivision of the SDN and can be used as such in future studies.

NR5A1 is a novel disease gene for 46,XX testicular and ovotesticular disorders of sex development.

PubMed

Baetens, Dorien; Stoop, Hans; Peelman, Frank; Todeschini, Anne-Laure; Rosseel, Toon; Coppieters, Frauke; Veitia, Reiner A; Looijenga, Leendert H J; De Baere, Elfride; Cools, Martine

2017-04-01

We aimed to identify the genetic cause in a cohort of 11 unrelated cases and two sisters with 46,XX SRY-negative (ovo)testicular disorders of sex development (DSD). Whole-exome sequencing (n = 9), targeted resequencing (n = 4), and haplotyping were performed. Immunohistochemistry of sex-specific markers was performed on patients' gonads. The consequences of mutation were investigated using luciferase assays, localization studies, and RNA-seq. We identified a novel heterozygous NR5A1 mutation, c.274C>T p.(Arg92Trp), in three unrelated patients. The Arg92 residue is highly conserved and located in the Ftz-F1 region, probably involved in DNA-binding specificity and stability. There were no consistent changes in transcriptional activation or subcellular localization. Transcriptomics in patient-derived lymphocytes showed upregulation of MAMLD1, a direct NR5A1 target previously associated with 46,XY DSD. In gonads of affected individuals, ovarian FOXL2 and testicular SRY-independent SOX9 expression observed. We propose NR5A1, previously associated with 46,XY DSD and 46,XX primary ovarian insufficiency, as a novel gene for 46,XX (ovo)testicular DSD. We hypothesize that p.(Arg92Trp) results in decreased inhibition of the male developmental pathway through downregulation of female antitestis genes, thereby tipping the balance toward testicular differentiation in 46,XX individuals. In conclusion, our study supports a role for NR5A1 in testis differentiation in the XX gonad.Genet Med 19 4, 367-376.

Sub-chronic indomethacin treatment and its effect on the male reproductive system of albino rats: possible protective role of black tea extract.

PubMed

Bagoji, Ishwar B; Hadimani, Gavishiddappa A; Yendigeri, Saeed M; Das, Kusal K

2017-05-01

Indomethacin is commonly used as a nonsteroidal anti-inflammatory drug (NSAID) to treat inflammation, arthritis and joint pains. Unfortunately, it has a wide range of adverse effects on the physiological system, including gonads. This study aimed to assess possible beneficial effects of black tea extract (BTE) against indomethacin-induced alteration of gonadal hormone levels in male rats. Adult male rats were divided into Group I (control), Group II (indomethacin, 5 mg/kg body weight [bwt.]; i.p., 21 days), Group III (BTE, 2.5 g tea leaf/dL of water, i.e. 2.5% of aqueous BTE, orally, 21 days) and Group IV (indomethacin+BTE, 21 days). Sperm count and motility, serum luteinising hormone (LH), follicle-stimulating hormone (FSH) and testosterone, along with histopathology of testes were studied. One-way ANOVA, followed by post-hoc t-test were conducted. Indomethacin-treated rats showed significant decrease in testicular weight, sperm count, sperm motility, serum gonadotropins and testosterone concentrations. Histopathology of the testes showed tortuous and distorted seminiferous tubules, marked thickening of the tubular basement membrane, reduced spermatogenesis process (>30%) and marked decrease in the number of interstitial cells of Leydig in indomethacin-treated rats. Interestingly, rats supplemented with BTE showed remarkable improvements in testicular weight gain, sperm count and motility, serum gonadotropins and testosterone concentrations, along with testicular histopathology. The results suggest that BTE might have potential ameliorative effects against sub-chronic indomethacin-induced alteration of gonadal hormone levels in male albino rats.

The contribution of p53 and Y chromosome long arm genes to regulation of apoptosis in mouse testis.

PubMed

Lech, Tomasz; Styrna, Józefa; Kotarska, Katarzyna

2018-03-01

Apoptosis of excessive or defective germ cells is a natural process occurring in mammalian testes. Tumour suppressor protein p53 is involved in this process both in developing and adult male gonads. Its contribution to testicular physiology is known to be modified by genetic background. The aim of this study was to evaluate the combined influence of the p53 and Y chromosome long arm genes on male germ cell apoptosis. Knockout of the transformation related protein 53 (Trp53) gene was introduced into congenic strains: B10.BR (intact Y chromosome) and B10.BR-Ydel (Y chromosome with a deletion in the long arm). The level of apoptosis in the testes of 19-day-old and 3-month-old male mice was determined using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate in situ nick-end labelling (TUNEL) method. The study revealed that although p53 is involved in germ cell apoptosis in peripubertal testes, this process can also be mediated by p53-independent mechanisms. However, activation of p53-independent apoptotic pathways in the absence of the p53 protein requires engagement of the multicopy Yq genes and was not observed in gonads of B10.BR-Ydel-p53-/- males. The role of Yq genes in the regulation of testicular apoptosis seems to be restricted to the initial wave of spermatogenesis and is not evident in adult gonads. The study confirmed, instead, that p53 does participate in spontaneous apoptosis in mature testes.

Pisrt1, a gene implicated in XX sex reversal, is expressed in gonads of both sexes during mouse development.

PubMed

Loffler, Kelly A; Combes, Alexander N; Wilhelm, Dagmar; Beverdam, Annemiek; Bowles, Jo; Koopman, Peter

2005-01-01

XX sex reversal syndromes not involving Sry provide an opportunity to identify and study genes important for sexual development. The polled intersex syndrome (PIS) in goats, which shares some features with blepharophimosis, ptosis, epicanthus inversus syndrome (BPES) in humans, exemplifies such syndromes. BPES is caused by defects in the forkhead transcription factor gene FOXL2, while PIS is caused by a large deletion of goat chromosome 1q43 that affects transcription of the genes Pisrt1 and Foxl2. Pisrt1 is a non-translated gene that has a sexually dimorphic expression pattern in goats. Here, we describe the structure and expression of the mouse Pisrt1 locus, to investigate its likely role in ovarian development more broadly in mammals. This gene showed some sequence similarity, and was found in a similar genomic context, to its goat and human orthologues. Expression analyses indicated that Pisrt1 is transcribed, and its mRNA polyadenylated and exported to the cytoplasm, but no significant open reading frames were found in a 1.5kb mouse genomic region corresponding to goat Pisrt1. Pisrt1 transcripts were expressed very broadly among tissues of the developing mouse embryo, and at similar levels in male and female gonads at each stage examined, as determined by in situ hybridisation and RT-PCR. This profile of expression suggests that Pisrt1 is unlikely to contribute to sex-specific events during gonadal development in mice and that divergent pathways of ovarian development operate among different mammalian species.

NR5A1 is a novel disease gene for 46,XX testicular and ovotesticular disorders of sex development

PubMed Central

Baetens, Dorien; Stoop, Hans; Peelman, Frank; Todeschini, Anne-Laure; Rosseel, Toon; Coppieters, Frauke; Veitia, Reiner A.; Looijenga, Leendert H.J.; De Baere, Elfride; Cools, Martine

2017-01-01

Purpose: We aimed to identify the genetic cause in a cohort of 11 unrelated cases and two sisters with 46,XX SRY-negative (ovo)testicular disorders of sex development (DSD). Methods: Whole-exome sequencing (n = 9), targeted resequencing (n = 4), and haplotyping were performed. Immunohistochemistry of sex-specific markers was performed on patients' gonads. The consequences of mutation were investigated using luciferase assays, localization studies, and RNA-seq. Results: We identified a novel heterozygous NR5A1 mutation, c.274C>T p.(Arg92Trp), in three unrelated patients. The Arg92 residue is highly conserved and located in the Ftz-F1 region, probably involved in DNA-binding specificity and stability. There were no consistent changes in transcriptional activation or subcellular localization. Transcriptomics in patient-derived lymphocytes showed upregulation of MAMLD1, a direct NR5A1 target previously associated with 46,XY DSD. In gonads of affected individuals, ovarian FOXL2 and testicular SRY-independent SOX9 expression observed. Conclusions: We propose NR5A1, previously associated with 46,XY DSD and 46,XX primary ovarian insufficiency, as a novel gene for 46,XX (ovo)testicular DSD. We hypothesize that p.(Arg92Trp) results in decreased inhibition of the male developmental pathway through downregulation of female antitestis genes, thereby tipping the balance toward testicular differentiation in 46,XX individuals. In conclusion, our study supports a role for NR5A1 in testis differentiation in the XX gonad. Genet Med 19 4, 367–376. PMID:27490115

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.

Neural Versus Gonadal GnIH: Are they Independent Systems? A Mini-Review.

PubMed

Bentley, George E; Wilsterman, Kathryn; Ernst, Darcy K; Lynn, Sharon E; Dickens, Molly J; Calisi, Rebecca M; Kriegsfeld, Lance J; Kaufer, Daniela; Geraghty, Anna C; viviD, Dax; McGuire, Nicolette L; Lopes, Patricia C; Tsutsui, Kazuyoshi

2017-12-01

Based on research in protochordates and basal vertebrates, we know that communication across the first endocrine axes likely relied on diffusion. Because diffusion is relatively slow, rapid responses to some cues, including stress-related cues, may have required further local control of axis outputs (e.g., steroid hormone production by the gonads). Despite the evolution of much more efficient circulatory systems and complex nervous systems in vertebrates, production of many "neuro"transmitters has been identified outside of the hypothalamus across the vertebrate phylogeny and these neurotransmitters are known to locally regulate endocrine function. Our understanding of tissue-specific neuropeptide expression and their role coordinating physiological/behavioral responses of the whole organism remains limited, in part, due to nomenclature and historic dogma that ignores local regulation of axis output. Here, we review regulation of gonadotropin-inhibitory hormone (GnIH) across the reproductive axis in birds and mammals to bring further attention to context-dependent disparities and similarities in neuropeptide production by the brain and gonads. We find that GnIH responsiveness to cues of stress appears conserved across species, but that the response of specific tissues and the direction of GnIH regulation varies. The implications of differential regulation across tissues remain unclear in most studies, but further work that manipulates and contrasts function in different tissues has the potential to inform us about both organism-specific function and endocrine axis evolution. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

The large Maf factor Traffic Jam controls gonad morphogenesis in Drosophila.

PubMed

Li, Michelle A; Alls, Jeffrey D; Avancini, Rita M; Koo, Karen; Godt, Dorothea

2003-11-01

Interactions between somatic and germline cells are critical for the normal development of egg and sperm. Here we show that the gene traffic jam (tj) produces a soma-specific factor that controls gonad morphogenesis and is required for female and male fertility. tj encodes the only large Maf factor in Drosophila melanogaster, an orthologue of the atypical basic Leu zipper transcription factors c-Maf and MafB/Kreisler in vertebrates. Expression of tj occurs in somatic gonadal cells that are in direct contact with germline cells throughout development. In tj mutant gonads, somatic cells fail to inter-mingle and properly envelop germline cells, causing an early block in germ cell differentiation. In addition, tj mutant somatic cells show an increase in the level of expression for several adhesion molecules. We propose that tj is a critical modulator of the adhesive properties of somatic cells, facilitating germline-soma interactions that are essential for germ cell differentiation.

GONADAL AND BONE MARROW DOSE IN MEDICAL DIAGNOSTIC RADIOLOGY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahmoud, K.A.; Mahfouz, M.M.; Mahmoud, M.E.

1961-08-01

Measurements were made of the active mean bone marrow, integral bone marrow, gonadal, and maximum skin doses from diagnostic x-ray procedures used in Cairo University Hospitals. The active mean marrow dose in cervical, dorsal, and lumbar spine diagnostic exposures were: found to be somewhat smaller than those reported by some western couatries. One of the most striking results of the survey was the relatively high values of the urinary tract cases investigated diagnostically; owing to the high incidence of urinary tract Schistosomiasis. The gonadal dose delivered to males and females was found to be almosi negligible for all diagnostic investigationsmore » of the spine, except for the lumbo-dorsal region which was within the range 50 to 500 mrads. It was also found that the gonadal dose was significant in investigations of the lower gastrointestinal tract, gall bladder, and urinary tract. (P.C.H.)« less

Development of a terrestrial vertebrate model for assessing bioavailability of cadmium in the fence lizard (Sceloporus undulatus) and in ovo effects on hatchling size and thyroid function.

PubMed

Brasfield, Sandra M; Bradham, Karen; Wells, Jason B; Talent, Larry G; Lanno, Roman P; Janz, David M

2004-03-01

In the terrestrial environment, standardized protocols are available for measuring the exposure and effects of contaminants to invertebrates, but none currently exist for vertebrates. In an effort to address this, we proposed that developing lizard embryos may be used as a terrestrial vertebrate model. Lizard eggs may be particularly susceptible to soil contamination and in ovo exposure may affect hatchling size, mortality, as well as thyroid function. Toxicant-induced perturbations of thyroid function resulting from in ovo chemical exposure may result in toxicity during the critical perinatal period in reptiles. Fertilized Eastern fence lizard (Sceloporus undulatus) eggs were placed in cadmium (Cd)-spiked expanded perlite (0, 1.48, 14.8, 148, 1480, 14,800 microg Cd/g, nominal concentrations), artificially incubated at 28 degrees C, and examined daily for mortality. Whole lizard hatchlings as well as failed hatches were homogenized in ethanol and the homogenate was divided for Cd body residue analysis and thyroid hormone (triiodothyronine (T3) and thyroxine (T4)) analyses. Acute mortality was observed in the two highest doses (1480 and 14800 microg Cd/g). Cadmium body residues showed a higher internal concentration with increasing exposure concentration indicating uptake of Cd. There was a decrease in T3:T4 ratio at the highest surviving dose (148 microg Cd/g), however, there were no differences observed in hatchling size measured as weight and snout-vent length, or in whole body thyroid hormone levels. In summary, this study has shown Cd amended to a solid phase representing soil (perlite) can traverse the thin, parchment-like shell membrane of the fence lizard egg and bioaccumulate in lizard embryos. We believe this study is a good first step in investigating and evaluating this species for use as a model.

Spatiotemporal expression profile of the Pumilio gene in the embryonic development of silkworm.

PubMed

Chen, Liang; You, Zaizhi; Xia, Hengchuan; Tang, Qi; Zhou, Yang; Yao, Qin; Chen, Keping

2014-01-01

We previously identified a pumilio gene in silkworm (Bombyx mori L.), designated BmPUM, which was specifically expressed in the ovary and testis. To further characterize this gene's involvement in silkworm development, we have determined the spatiotemporal expression pattern of BmPUM during all embryonic stages. Real-time polymerase chain reaction (RT-PCR) analysis revealed that BmPUM was expressed in all stages of silkworm embryos and that its transcript levels displayed two distinct peaks. The first was observed at the germ-band formation stage (1 d after oviposition) and dropped to a low level at the gonad formation stage (5 d after oviposition). The second was detected at the stage of bristle follicle occurrence (6 d after oviposition), which was confirmed by Western blot analysis and immunohistochemistry. Nanos (Nos), functioning together with Pum in abdomen formation of Drosophila embryos, was also highly expressed at the beginning (0 h to 1 d after oviposition) of embryogenesis, but its transcript levels were very low after the stage of germ-band formation. These results suggest that BmPUM functions with Bombyx mori nanos (Bm-nanos) at the early stages of silkworm embryonic development, and may then play a role in gonad formation and the occurrence of bristle follicles. Our data thus provide a foundation to uncover the role of BmPUM during silkworm development.

Expression studies of the PIS-regulated genes suggest different mechanisms of sex determination within mammals.

PubMed

Pannetier, M; Servel, N; Cocquet, J; Besnard, N; Cotinot, C; Pailhoux, E

2003-01-01

In mammals, the Y-located SRY gene is known to induce testis formation from the indifferent gonad. A related gene, SOX9, also plays a critical role in testis differentiation in mammals, in birds and reptiles. It is now assumed that SRY acts upstream of SOX9 in the sex determination cascade, but the regulatory link which should exist between these two genes remains unknown. Studies on XX sex reversal in polled goats (PIS mutation: Polled Intersex Syndrome) have led to the discovery of a female-specific locus crucial for ovarian differentiation. This genomic region is composed of at least two genes, FOXL2 and PISRT1, which share a common transcriptional regulatory region, PIS. In this review, we present the expression pattern of these PIS-regulated genes in mice. The FOXL2 expression profile of mice is similar to that described in goats in accordance with a conserved role of this ovarian differentiating gene in mammals. On the contrary, the PISRT1 expression profile is different between mice and goats, suggesting different mechanisms of the primary switch in the testis determination process within mammals. A model based on two different modes of SOX9 regulation in mice and other mammals is proposed in order to integrate our results into the current scheme of gonad differentiation. Copyright 2003 S. Karger AG, Basel

Molecular cloning, expression analysis and transcript localization of testicular orphan nuclear receptor 2 in the male catfish, Clarias batrachus.

PubMed

Murugananthkumar, R; Akhila, M V; Rajakumar, A; Mamta, S K; Sudhakumari, C C; Senthilkumaran, B

2016-12-01

Testicular receptor 2 (TR2; also known as Nr2c1) is one of the first orphan nuclear receptors identified and known to regulate various physiological process with or without any ligand. In this study, we report the cloning of full length nr2c1 and its expression analysis during gonadal development, seasonal testicular cycle and after human chorionic gonadotropin (hCG) induction. In addition, in situ hybridization (ISH) was performed to localize nr2c1 transcripts in adult testis and whole catfish (1day post hatch). Tissue distribution and gonadal ontogeny studies revealed high expression of nr2c1 in developing and adult testis. Early embryonic stage-wise expression of nr2c1 seems to emphasize its importance in cellular differentiation and development. Substantial expression of nr2c1 during pre-spawning phase and localization of nr2c1 transcripts in sperm/spermatids were observed. Significant upregulation after hCG induction indicate that nr2c1 is under the regulation of gonadotropins. Whole mount ISH analysis displayed nr2c1 expression in notochord indicating its role in normal vertebrate development. Taken together, our findings suggest that nr2c1 may have a plausible role in the testicular and embryonic development of catfish. Copyright © 2015. Published by Elsevier Inc.

Wide spectrum of NR5A1‐related phenotypes in 46,XY and 46,XX individuals

PubMed Central

Domenice, Sorahia; Machado, Aline Zamboni; Ferreira, Frederico Moraes; Ferraz‐de‐Souza, Bruno; Lerario, Antonio Marcondes; Lin, Lin; Nishi, Mirian Yumie; Gomes, Nathalia Lisboa; da Silva, Thatiana Evelin; Silva, Rosana Barbosa; Correa, Rafaela Vieira; Montenegro, Luciana Ribeiro; Narciso, Amanda; Costa, Elaine Maria Frade; Achermann, John C

2016-01-01

Steroidogenic factor 1 (NR5A1, SF‐1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1‐related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype‐phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian‐determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1‐related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever‐expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal dysfunction. Birth Defects Research (Part C) 108:309–320, 2016. © 2016 The Authors Birth Defects Research Part C: Embryo Today: Reviews Published by Wiley Periodicals, Inc. PMID:28033660

Spatio-Temporal Variation in Effects of Upwelling on the Fatty Acid Composition of Benthic Filter Feeders in the Southern Benguela Ecosystem: Not All Upwelling Is Equal

PubMed Central

McQuaid, Christopher David; Noyon, Margaux

2016-01-01

Variability in mesoscale nearshore oceanographic conditions plays an important role in the distribution of primary production and food availability for intertidal consumers. Advection of nutrient rich waters by upwelling usually allows the proliferation of diatoms, later replaced by dinoflagellates. We examined upwelling effects on the fatty acid (FA) signature of a benthic intertidal filter feeder to identify its response to pulsed variability in food availability. The study took place in two contrasting seasons and at two upwelling and two non-upwelling sites interspersed within the southern Benguela upwelling system of South Africa. We investigated the FA composition of the adductor muscles and gonads of the mussel Mytilus galloprovincialis to assess how FA are apportioned to the different tissues and whether this changes between upwelling and non-upwelling conditions. In situ temperature loggers used to identify upwelling conditions at the four sites indicated that such events occurred only at the upwelling centres and only in summer. Tissues differed strongly, with gonads presenting a higher proportion of essential FAs. This could reflect the faster turnover rate of gonad tissue or preferential retention of specific FA for reproductive purposes. FA composition did not vary as a direct function of upwelling, but there were strong dissimilarities among sites. Upwelling influenced mussel diets at one upwelling site while at the other, the expected signature of upwelling was displaced downstream of the core of upwelling. Condition Index (CI) and Gonad Index (GI) differed among sites and were not influenced by upwelling, with GI being comparable among sites. In addition, FA proportions were consistent among sites, indicating similar food quality and quantity over time and under upwelling and non-upwelling conditions. This suggests that the influence of upwelling on the west coast of South Africa is pervasive and diffuse, rather than discrete; while nearshore retention or advection of upwelled water is critical and site-specific so that the effects of upwelling differ even among sites categorised as upwelling centres. PMID:27570968

The tapeworm Ligula intestinalis (Cestoda: Pseudophyllidea) inhibits LH expression and puberty in its teleost host, Rutilus rutilus.

PubMed

Carter, V; Pierce, R; Dufour, S; Arme, C; Hoole, D

2005-12-01

The tapeworm Ligula intestinalis occurs in the body cavity of its cyprinid second intermediate host, in this study the roach Rutilus rutilus, and inhibits host gonadal development. The mechanism by which infected fish are prevented from reproducing is unknown. Comparison of parameters, such as body length and weight, and condition factor and age, between infected and uninfected individuals, indicated only minor effects of parasitism on growth and condition. In contrast, seasonal gonadal development, as observed in uninfected fish, did not occur in infected fish, and gonads remained small and blocked at the primary oocyte stage in female roach. As immature ovaries and testes are still present, the parasite is presumed to act upon the brain-pituitary-gonadal axis of the fish to inhibit further development of reproductive organs. We investigated the Ligula/fish interaction at the level of the pituitary gland by determination of gonadotrophin (LH) content using a heterologous RIA for carp (Cyprinus carpio) LHbeta subunit. The results indicated that the pituitary glands of infected roach contained approximately 50% less LH than non-infected fish. After the cloning and sequencing of roach LHbeta subunit, we measured roach LHbeta mRNA levels by real-time RT-PCR. A corresponding 50% reduction in LHbeta mRNA pituitary levels was determined. These results reflect a significant and measurable effect of parasitism on the pituitary gland, and lend support to the hypothesis that excretory/secretory products released from the parasite interact with the brain-pituitary-gonadal axis of the fish host and thus inhibit gonadal development.

Gonadal Transcriptome Alterations in Response to Dietary Energy Intake: Sensing the Reproductive Environment

PubMed Central

Martin, Bronwen; Pearson, Michele; Brenneman, Randall; Golden, Erin; Wood, William; Prabhu, Vinayakumar; Becker, Kevin G.; Mattson, Mark P.; Maudsley, Stuart

2009-01-01

Reproductive capacity and nutritional input are tightly linked and animals' specific responses to alterations in their physical environment and food availability are crucial to ensuring sustainability of that species. We have assessed how alterations in dietary energy intake (both reductions and excess), as well as in food availability, via intermittent fasting (IF), affect the gonadal transcriptome of both male and female rats. Starting at four months of age, male and female rats were subjected to a 20% or 40% caloric restriction (CR) dietary regime, every other day feeding (IF) or a high fat-high glucose (HFG) diet for six months. The transcriptional activity of the gonadal response to these variations in dietary energy intake was assessed at the individual gene level as well as at the parametric functional level. At the individual gene level, the females showed a higher degree of coherency in gonadal gene alterations to CR than the males. The gonadal transcriptional and hormonal response to IF was also significantly different between the male and female rats. The number of genes significantly regulated by IF in male animals was almost 5 times greater than in the females. These IF males also showed the highest testosterone to estrogen ratio in their plasma. Our data show that at the level of gonadal gene responses, the male rats on the IF regime adapt to their environment in a manner that is expected to increase the probability of eventual fertilization of females that the males predict are likely to be sub-fertile due to their perception of a food deficient environment. PMID:19127293

UV laser radiation alters the embryonic protein profile of adrenal-kidney-gonadal complex and gonadal differentiation in the lizard, Calotes Versicolor.

PubMed

Khodnapur, Bharati S; Inamdar, Laxmi S; Nindi, Robertraj S; Math, Shivkumar A; Mulimani, B G; Inamdar, Sanjeev R

2015-02-01

To examine the impact of ultraviolet (UV) laser radiation on the embryos of Calotes versicolor in terms of its effects on the protein profile of the adrenal-kidney-gonadal complex (AKG), sex determination and differentiation, embryonic development and hatching synchrony. The eggs of C. versicolor, during thermo-sensitive period (TSP), were exposed to third harmonic laser pulses at 355 nm from a Q-switched Nd:YAG laser for 180 sec. Subsequent to the exposure they were incubated at the male-producing temperature (MPT) of 25.5 ± 0.5°C. The AKG of hatchlings was subjected to protein analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and to histology. The UV laser radiation altered the expression of the protein banding pattern in the AKG complex of hatchlings and it also affected the gonadal sex differentiation. SDS-PAGE of AKG of one-day-old hatchlings revealed a total of nine protein bands in the control group whereas UV laser irradiated hatchlings expressed a total of seven protein bands only one of which had the same Rf as a control band. The UV laser treated hatchlings have an ovotestes kind of gonad exhibiting a tendency towards femaleness instead of the typical testes. It is inferred that 355 nm UV laser radiation during TSP induces changes in the expression of proteins as well as their secretions. UV laser radiation had an impact on the gonadal differentiation pathway but no morphological anomalies were noticed.

Ultrastructure of the protonephridia of larval Rugiloricus cf. cauliculus, male Armorloricus elegans, and female Nanaloricus mysticus (Loricifera).

PubMed

Neuhaus, Birger; Kristensen, Reinhardt Møbjerg

2007-04-01

The protonephridial system of several Loricifera was studied by transmission electron microscopy. A larval specimen of Rugiloricus cf. cauliculus possesses two protonephridia, which are "capped" frontally by a compact mass of still undifferentiated gonadal cells. Each protonephridium consists of four monociliary terminal cells and four canal cells with a diplosome but no cilia. Because of incomplete series of sections and unsatisfactory fixation, the outleading cell(s) could not be detected. In a male specimen of Armorloricus elegans, each gonad contains two protonephridia that open into the gonadal lumen. Each protonephridium consists of two monociliary terminal cells, each forming a filter, two nonciliated canal cells, and two nephroporus cells. The protonephridial lumina of the latter cells fuse to one common lumen, which unites with the gonadal lumen. Preliminary observations on the protonephridia of a female Nanaloricus mysticus reveal a more complicated arrangement of interdigitating terminal and canal cells. One or two terminal cells form their own individual filter or four cells form a common compound filter. The cilium of the terminal cells of all species investigated are surrounded by a palisade of nine microvilli that support the filter barrier made of an extracellular matrix. An additional filter diaphragm could be traced between the pores in the cell wall of each terminal cell of A. elegans. The urogenital system of the Loricifera differs from that of the Priapulida in that the protonephridia of the former are completely integrated into the gonad, whereas the excretory organs of the latter open into the urogenital duct caudally of the gonads. Copyright (c) 2007 Wiley-Liss, Inc.

Detection of Spiroplasma and Wolbachia in the bacterial gonad community of Chorthippus parallelus.

PubMed

Martínez-Rodríguez, P; Hernández-Pérez, M; Bella, J L

2013-07-01

We have recently detected the endosymbiont Wolbachia in multiple individuals and populations of the grasshopper Chorthippus parallelus (Orthoptera: acrididae). This bacterium induces reproductive anomalies, including cytoplasmic incompatibility. Such incompatibilities may help explain the maintenance of two distinct subspecies of this grasshopper, C. parallelus parallelus and C. parallelus erythropus, which are involved in a Pyrenean hybrid zone that has been extensively studied for the past 20 years, becoming a model system for the study of genetic divergence and speciation. To evaluate whether Wolbachia is the sole bacterial infection that might induce reproductive anomalies, the gonadal bacterial community of individuals from 13 distinct populations of C. parallelus was determined by denaturing gradient gel electrophoresis analysis of bacterial 16S rRNA gene fragments and sequencing. The study revealed low bacterial diversity in the gonads: a persistent bacterial trio consistent with Spiroplasma sp. and the two previously described supergroups of Wolbachia (B and F) dominated the gonad microbiota. A further evaluation of the composition of the gonad bacterial communities was carried out by whole cell hybridization. Our results confirm previous studies of the cytological distribution of Wolbachia in C. parallelus gonads and show a homogeneous infection by Spiroplasma. Spiroplasma and Wolbachia cooccurred in some individuals, but there was no significant association of Spiroplasma with a grasshopper's sex or with Wolbachia infection, although subtle trends might be detected with a larger sample size. This information, together with previous experimental crosses of this grasshopper, suggests that Spiroplasma is unlikely to contribute to sex-specific reproductive anomalies; instead, they implicate Wolbachia as the agent of the observed anomalies in C. parallelus.

Ecotoxicological evaluation of tributyltin toxicity to the equilateral venus clam, Gomphina veneriformis (Bivalvia: Veneridae).

PubMed

Park, Kiyun; Kim, Rosa; Park, Jung Jun; Shin, Hyun Chool; Lee, Jung Sick; Cho, Hyeon Seo; Lee, Yeon Gyu; Kim, Jongkyu; Kwak, Inn-Sil

2012-03-01

Tributyltin (TBT) is the most common pesticide in marine and freshwater environments. To evaluate the potential ecological risk posed by TBT, we measured biological responses such as growth rate, gonad index, sex ratio, the percentage of intersex gonads, filtration rate, and gill abnormalities in the equilateral venus clam (Gomphina veneriformis). Additionally, the biochemical and molecular responses were evaluated in G. veneriformis exposed to various concentrations of TBT. The growth of G. veneriformis was significantly delayed in a dose-dependent manner after exposure to all tested TBT concentrations. After TBT was administered to G. veneriformis, the gonad index decreased and the sex balance was altered. The percentage of intersex gonads also increased significantly in treated females, whereas no intersex gonads were detected in the solvent control group. Additionally, intersex gonads were detected in male G. veneriformis specimens exposed to relatively high TBT concentrations (20 μg L⁻¹). The filtration rate was also reduced in a dose-dependent manner in TBT-exposed G. veneriformis. We also noted abnormal gill morphology in TBT-exposed G. veneriformis. Furthermore, increases in antioxidant enzyme activities were observed in TBT-exposed G. veneriformis clams, regardless of dosage. Vitellogenin gene expression also increased significantly in a dose-dependent manner in G. veneriformis exposed to TBT. These results provide valuable information regarding our understanding of the toxicology of TBT in G. veneriformis. Moreover, the responses of biological and molecular factors could be utilized as information for risk assessments and marine monitoring of TBT toxicity. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Oestrogens and spermatogenesis

PubMed Central

Carreau, Serge; Hess, Rex A.

2010-01-01

The role of oestrogens in male reproductive tract physiology has for a long time been a subject of debate. The testis produces significant amounts of oestrogenic hormones, via aromatase, and oestrogen receptors (ERs)α (ESR1) and ERβ (ESR2) are selectively expressed in cells of the testis as well as the epididymal epithelium, depending upon species. This review summarizes the current knowledge concerning the presence and activity of aromatase and ERs in testis and sperm and the potential roles that oestrogens may have in mammalian spermatogenesis. Data show that physiology of the male gonad is in part under the control of a balance of androgens and oestrogens, with aromatase serving as a modulator. PMID:20403867

Transcriptome analysis reveals differentially expressed genes associated with germ cell and gonad development in the Southern bluefin tuna (Thunnus maccoyii).

PubMed

Bar, Ido; Cummins, Scott; Elizur, Abigail

2016-03-10

Controlling and managing the breeding of bluefin tuna (Thunnus spp.) in captivity is an imperative step towards obtaining a sustainable supply of these fish in aquaculture production systems. Germ cell transplantation (GCT) is an innovative technology for the production of inter-species surrogates, by transplanting undifferentiated germ cells derived from a donor species into larvae of a host species. The transplanted surrogates will then grow and mature to produce donor-derived seed, thus providing a simpler alternative to maintaining large-bodied broodstock such as the bluefin tuna. Implementation of GCT for new species requires the development of molecular tools to follow the fate of the transplanted germ cells. These tools are based on key reproductive and germ cell-specific genes. RNA-Sequencing (RNA-Seq) provides a rapid, cost-effective method for high throughput gene identification in non-model species. This study utilized RNA-Seq to identify key genes expressed in the gonads of Southern bluefin tuna (Thunnus maccoyii, SBT) and their specific expression patterns in male and female gonad cells. Key genes involved in the reproductive molecular pathway and specifically, germ cell development in gonads, were identified using analysis of RNA-Seq transcriptomes of male and female SBT gonad cells. Expression profiles of transcripts from ovary and testis cells were compared, as well as testis germ cell-enriched fraction prepared with Percoll gradient, as used in GCT studies. Ovary cells demonstrated over-expression of genes related to stem cell maintenance, while in testis cells, transcripts encoding for reproduction-associated receptors, sex steroids and hormone synthesis and signaling genes were over-expressed. Within the testis cells, the Percoll-enriched fraction showed over-expression of genes that are related to post-meiosis germ cell populations. Gonad development and germ cell related genes were identified from SBT gonads and their expression patterns in ovary and testis cells were determined. These expression patterns correlate with the reproductive developmental stage of the sampled fish. The majority of the genes described in this study were sequenced for the first time in T. maccoyii. The wealth of SBT gonadal and germ cell-related gene sequences made publicly available by this study provides an extensive resource for further GCT and reproductive molecular biology studies of this commercially valuable fish.

Identical NR5A1 Missense Mutations in Two Unrelated 46,XX Individuals with Testicular Tissues.

PubMed

Igarashi, Maki; Takasawa, Kei; Hakoda, Akiko; Kanno, Junko; Takada, Shuji; Miyado, Mami; Baba, Takashi; Morohashi, Ken-Ichirou; Tajima, Toshihiro; Hata, Kenichiro; Nakabayashi, Kazuhiko; Matsubara, Yoichi; Sekido, Ryohei; Ogata, Tsutomu; Kashimada, Kenichi; Fukami, Maki

2017-01-01

The role of monogenic mutations in the development of 46,XX testicular/ovotesticular disorders of sex development (DSD) remains speculative. Although mutations in NR5A1 are known to cause 46,XY gonadal dysgenesis and 46,XX ovarian insufficiency, such mutations have not been implicated in testicular development of 46,XX gonads. Here, we identified identical NR5A1 mutations in two unrelated Japanese patients with 46,XX testicular/ovotesticular DSD. The p.Arg92Trp mutation was absent from the clinically normal mothers and from 200 unaffected Japanese individuals. In silico analyses scored p.Arg92Trp as probably pathogenic. In vitro assays demonstrated that compared with wild-type NR5A1, the mutant protein was less sensitive to NR0B1-induced suppression on the SOX9 enhancer element. Other sequence variants found in the patients were unlikely to be associated with the phenotype. The results raise the possibility that specific mutations in NR5A1 underlie testicular development in genetic females. © 2016 WILEY PERIODICALS, INC.

Loss-of-function mutation in GATA4 causes anomalies of human testicular development

PubMed Central

Lourenço, Diana; Brauner, Raja; Rybczyńska, Magda; Nihoul-Fékété, Claire; McElreavey, Ken; Bashamboo, Anu

2011-01-01

Approximately 1 of every 250 newborns has some abnormality of genital and/or gonadal development. However, a specific molecular cause is identified in only 20% of these cases of disorder of sex development (DSD). We identified a family of French origin presenting with 46,XY DSD and congenital heart disease. Sequencing of the ORF of GATA4 identified a heterozygous missense mutation (p.Gly221Arg) in the conserved N-terminal zinc finger of GATA4. This mutation was not observed in 450 ancestry-matched control individuals. The mutation compromised the ability of the protein to bind to and transactivate the anti-Müllerian hormone (AMH) promoter. The mutation does not interfere with the direct protein–protein interaction, but it disrupts synergistic activation of the AMH promoter by GATA4 and NR5A1. The p.Gly221Arg mutant protein also failed to bind to a known protein partner FOG2 that is essential for gonad formation. Our data demonstrate the key role of GATA4 in human testicular development. PMID:21220346

Expression profile of doublesex/male abnormal-3-related transcription factor-1 during gonadal sex change in the protogynous wrasse, Halichoeres trimaculatus.

PubMed

Nozu, Ryo; Horiguchi, Ryo; Kobayashi, Yasuhisa; Nakamura, Masaru

2015-11-01

Sex change in fish involves a dramatic transformation of gonadal tissue and a switch in gametogenesis. Doublesex/male abnormal-3-related transcription factor-1 (DMRT1), encoded by the DMRT1 gene, is involved in testicular differentiation in a wide range of vertebrates as well as in sexual differentiation and gonadal sex change. In the present study, we investigated changes in the expression of dmrt1 during artificial gonadal sex change in the three-spot wrasse, Halichoeres trimaculatus, by real-time quantitative PCR and immunolocalization, using an anti-wrasse-Dmrt1 antibody that we prepared. We found that dmrt1 expression was predominantly observed in the testes, and that Dmrt1 was expressed in Sertoli cells of testes and a few granulosa cells surrounding vitellogenic oocytes of the ovary. Additionally, the upregulation of dmrt1 expression was consistent with an increase in spermatogenic cyst quantity rather than proliferation of presumptive spermatogonia, suggesting that dmrt1 is involved in the progression of spermatogenesis during sex change. Changes in the localization of Dmrt1 during gonadal sex change further implied that Sertoli cells originate from somatic cells adjacent to gonial germ cells during testicular formation in the three-spot wrasse. © 2015 Wiley Periodicals, Inc.

Characterization of gonadal soma-derived factor expression during sex change in the protogynous wrasse, Halichoeres trimaculatus.

PubMed

Horiguchi, Ryo; Nozu, Ryo; Hirai, Toshiaki; Kobayashi, Yasuhisa; Nagahama, Yoshitaka; Nakamura, Masaru

2013-04-01

Sex change in fishes provides a good experimental model for understanding the mechanisms and plasticity of sex determination and differentiation. The three-spot wrasse, Halichoeres trimaculatus is a protogynous hermaphrodite. During sex change from female to male, the ovary is replaced by the testis through the degeneration of oocytes and subsequent spermatogenesis. In the present study, we cloned a cDNA-encoding gonadal soma-derived factor (GSDF) from protogynous wrasse and examined its expression pattern in the sexually mature gonads and the sex-changing gonad induced experimentally by aromatase inhibition. Expression of gsdf was predominantly observed in the testis, and it was mainly localized to the supporting cells surrounding the spermatogonia. In the ovary, only slight expression of gsdf was observed in morphologically undifferentiated supporting cells in contact with oogonia. During sex change, strong expression of gsdf appeared first in the supporting cells surrounding the gonial germ cells before the onset of spermatogenesis. Thereafter, the expression of gsdf continually increased in the supporting cells surrounding the proliferating spermatogonia throughout the sex change. These results suggest that gsdf is involved in the proliferation of spermatogonia and subsequent spermatogenesis in both the testis and the gonad in the early stages of sex change. Copyright © 2013 Wiley Periodicals, Inc.

Comparing postnatal development of gonadal hormones and associated social behaviors in rats, mice, and humans.

PubMed

Bell, Margaret R

2018-05-14

Postnatal development includes dramatic changes in gonadal hormones and the many social behaviors they help regulate, both in rodents and humans. Parental care-seeking is the most salient social interaction in neonates and infants, play and pro-social behaviors are commonly studied in juveniles, and the development of aggression and sexual behavior begins in peripubertal stages but continues through late adolescence into adulthood. While parental behaviors are shown after reproductive success in adulthood, alloparenting behaviors are actually high in juveniles as well. These behaviors are sensitive to both early life organizational effects of gonadal hormones and later life activational regulation. However, changes in circulating gonadal hormones and the display of the above behaviors over development differs between rats, mice and humans. These endpoints are of interest to endocrinologist, toxicologists, neuroscientists because of their relevance to mental health disorders and their vulnerability to effects of endocrine disrupting chemical exposure. As such, the goal of this minireview is to succinctly describe and relate the postnatal development of gonadal hormones and social behaviors to each other, over time and across animal models. Ideally, this will help identify appropriate animal models and age ranges for continued study of both normative development and in contexts of environmental disruption.

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 ...

Event-related brain potentials to emotional images and gonadal steroid hormone levels in patients with schizophrenia and paired controls

PubMed Central

Champagne, Julie; Mendrek, Adrianna; Germain, Martine; Hot, Pascal; Lavoie, Marc E.

2014-01-01

Prominent disturbances in the experience, expression, and emotion recognition in patients with schizophrenia have been relatively well documented over the last few years. Furthermore, sex differences in behavior and brain activity, associated with the processing of various emotions, have been reported in the general population and in schizophrenia patients. Others proposed that sex differences should be rather attributed to testosterone, which may play a role in the etiology of schizophrenia. Also, it had been suggested that estradiol may play a protective role in schizophrenia. Surprisingly, few studies investigating this pathology have focused on both brain substrates and gonadal steroid hormone levels, in emotional processing. In the present study, we investigated electrocortical responses related to emotional valence and arousal as well as gonadal steroid hormone levels in patients with schizophrenia. Event-Related Potentials (ERP) were recorded during exposition to emotional pictures in 18 patients with schizophrenia and in 24 control participants paired on intelligence, manual dominance and socioeconomic status. Given their previous sensitivity to emotional and attention processes, the P200, N200 and the P300 were selected for analysis. More precisely, emotional valence generally affects early components (N200), which reflect early process of selective attention, whereas emotional arousal and valence both influences the P300 component, which is related to memory context updating, and stimulus categorization. Results showed that, in the control group, the amplitude of the N200 was significantly more lateralized over the right hemisphere, while there was no such lateralization in patients with schizophrenia. In patients with schizophrenia, significantly smaller anterior P300 amplitude was observed to the unpleasant, compared to the pleasant. That anterior P300 reduction was also correlated with negative symptoms. The N200 and P300 amplitudes were positively correlated with the estradiol level in all conditions, revealing that the N200 and the P300 were reduced, when estradiol level was higher. Conversely, only the P300 amplitude showed positive correlation with the testosterone level. PMID:24966840

Event-related brain potentials to emotional images and gonadal steroid hormone levels in patients with schizophrenia and paired controls.

PubMed

Champagne, Julie; Mendrek, Adrianna; Germain, Martine; Hot, Pascal; Lavoie, Marc E

2014-01-01

Prominent disturbances in the experience, expression, and emotion recognition in patients with schizophrenia have been relatively well documented over the last few years. Furthermore, sex differences in behavior and brain activity, associated with the processing of various emotions, have been reported in the general population and in schizophrenia patients. Others proposed that sex differences should be rather attributed to testosterone, which may play a role in the etiology of schizophrenia. Also, it had been suggested that estradiol may play a protective role in schizophrenia. Surprisingly, few studies investigating this pathology have focused on both brain substrates and gonadal steroid hormone levels, in emotional processing. In the present study, we investigated electrocortical responses related to emotional valence and arousal as well as gonadal steroid hormone levels in patients with schizophrenia. Event-Related Potentials (ERP) were recorded during exposition to emotional pictures in 18 patients with schizophrenia and in 24 control participants paired on intelligence, manual dominance and socioeconomic status. Given their previous sensitivity to emotional and attention processes, the P200, N200 and the P300 were selected for analysis. More precisely, emotional valence generally affects early components (N200), which reflect early process of selective attention, whereas emotional arousal and valence both influences the P300 component, which is related to memory context updating, and stimulus categorization. Results showed that, in the control group, the amplitude of the N200 was significantly more lateralized over the right hemisphere, while there was no such lateralization in patients with schizophrenia. In patients with schizophrenia, significantly smaller anterior P300 amplitude was observed to the unpleasant, compared to the pleasant. That anterior P300 reduction was also correlated with negative symptoms. The N200 and P300 amplitudes were positively correlated with the estradiol level in all conditions, revealing that the N200 and the P300 were reduced, when estradiol level was higher. Conversely, only the P300 amplitude showed positive correlation with the testosterone level.

Opposing effects of D-aspartic acid and nitric oxide on tuning of testosterone production in mallard testis during the reproductive cycle.

PubMed

Di Fiore, Maria M; Lamanna, Claudia; Assisi, Loredana; Botte, Virgilio

2008-07-04

D-Aspartic acid (D-Asp) and nitric oxide (NO) play an important role in tuning testosterone production in the gonads of male vertebrates. In particular, D-Asp promotes either the synthesis or the release of testosterone, whereas NO inhibits it. In this study, we have investigated for the first time in birds the putative effects of D-Asp and NO on testicular testosterone production in relation to two phases of the reproductive cycle of the adult captive wild-strain mallard (Anas platyrhynchos) drake. It is a typical seasonal breeder and its cycle consists of a short reproductive period (RP) in the spring (April-May) and a non reproductive period (NRP) in the summer (July), a time when the gonads are quiescent. The presence and the localization of D-Asp and NO in the testis and the trends of D-Asp, NO and testosterone levels were assessed during the main phases of the bird's reproductive cycle. Furthermore, in vitro experiments revealed the direct effect of exogenously administered D-Asp and NO on testosterone steroidogenesis. By using immunohistochemical (IHC) techniques, we studied the presence and the distributional pattern of D-Asp and NO in the testes of RP and NRP drakes. D-Asp levels were evaluated by an enzymatic method, whereas NO content, via nitrite, was assessed using biochemical measurements. Finally, immunoenzymatic techniques determined testicular testosterone levels. IHC analyses revealed the presence of D-Asp and NO in Leydig cells. The distributional pattern of both molecules was in some way correlated to the steroidogenic pathway, which is involved in autocrine testosterone production. Indeed, whereas NO was present only during the NRP, D-Asp was almost exclusively present during the RP. Consistently, the high testosterone testicular content occurring during RP was coupled to a high D-Asp level and a low NO content in the gonad. By contrast, in sexually inactive drakes (NRP), the low testosterone content in the gonad was coupled to a low D-Asp content and to a relatively high NO level. Consequently, to determine the exogenous effects of the two amino acids on testosterone synthesis, we carried out in vitro experiments using testis sections deriving from both the RP and NRP. When testis slices were incubated for 60 or 120 min with D-Asp, testosterone was enhanced, whereas in the presence of L-Arg, a precursor of NO, it was inhibited. Our results provide new insights into the involvement of D-Asp and NO in testicular testosterone production in the adult captive wild-strain mallard drake. The localization of these two molecules in the Leydig cells in different periods of the reproductive cycle demonstrates that they play a potential role in regulating local testosterone production.

Gonadotropin-releasing hormone analogues inhibit leiomyoma extracellular matrix despite presence of gonadal hormones.

PubMed

Malik, Minnie; Britten, Joy; Cox, Jeris; Patel, Amrita; Catherino, William H

2016-01-01

To determine the effect of GnRH analogues (GnRH-a) leuprolide acetate (LA) and cetrorelix acetate on gonadal hormone-regulated expression of extracellular matrix in uterine leiomyoma three-dimensional (3D) cultures. Laboratory study. University research laboratory. Women undergoing hysterectomy for symptomatic leiomyomas. The 3D cell cultures, protein analysis, Western blot, immunohistochemistry. Expression of extracellular matrix proteins, collagen 1, fibronectin, and versican in leiomyoma cells 3D cultures exposed to E2, P, LA, cetrorelix acetate, and combinations for 24- and 72-hour time points. The 3D leiomyoma cultures exposed to E2 for 24 hours demonstrated an increased expression of collagen-1 and fibronectin, which was maintained for up to 72 hours, a time point at which versican was up-regulated significantly. Although P up-regulated collagen-1 protein (1.29 ± 0.04) within 24 hours of exposure, significant increase in all extracellular matrix (ECM) proteins was observed when the gonadal hormones were used concomitantly. Significant decrease in the amount of ECM proteins was observed on use of GnRH-a, LA and cetrorelix, with 24-hour exposure. Both the compounds also significantly decreased ECM protein concentration despite the presence of E2 or both gonadal hormones. This study demonstrates that GnRH-a directly affect the gonadal hormone-regulated collagen-1, fibronectin, and versican production in their presence. These findings suggest that localized therapy with GnRH-a may inhibit leiomyoma growth even in the presence of endogenous gonadal hormone exposure, thereby providing a mechanism to eliminate the hypoestrogenic side effects associated with GnRH-a therapy. Published by Elsevier Inc.

Transcription of key genes regulating gonadal steroidogenesis in control and ketoconazole- or vinclozolin-exposed fathead minnows

DOE Office of Scientific and Technical Information (OSTI.GOV)

Villeneuve, Daniel L.; Blake, Lindsey S.; Brodin, Jeffrey

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 agemore » 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.« less

A timecourse analysis of systemic and gonadal effects of temperature on sexual development of the red-eared slider turtle Trachemys scripta elegans.

PubMed

Czerwinski, Michael; Natarajan, Anirudh; Barske, Lindsey; Looger, Loren L; Capel, Blanche

2016-12-01

Temperature dependent sex determination (TSD) is the process by which the environmental temperature experienced during embryogenesis influences the sex of an organism, as in the red-eared slider turtle Trachemys scripta elegans. In accord with current paradigms of vertebrate sex determination, temperature is believed to exert its effects on sexual development in T. scripta entirely within the middle third of development, when the gonad is forming. However, whether temperature regulates the transcriptome in T. scripta early embryos in a manner that could influence secondary sex characteristics or establish a pro-male or pro-female environment has not been investigated. In addition, apart from a handful of candidate genes, very little is known about potential similarities between the expression cascade during TSD and the genetic cascade that drives mammalian sex determination. Here, we conducted an unbiased transcriptome-wide analysis of the effects of male- and female-promoting temperatures on the turtle embryo prior to gonad formation, and on the gonad during the temperature sensitive period. We found sexually dimorphic expression reflecting differences in steroidogenic enzymes and brain development prior to gonad formation. Within the gonad, we mapped a cascade of differential expression similar to the genetic cascade established in mammals. Using a Hidden Markov Model based clustering approach, we identified groups of genes that show heterochronic shifts between M. musculus and T. scripta. We propose a model in which multiple factors influenced by temperature accumulate during early gonadogenesis, and converge on the antagonistic regulation of aromatase to canalize sex determination near the end of the temperature sensitive window of development. Copyright © 2016 Elsevier Inc. All rights reserved.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

True hermaphroditism in a 46, XY individual, caused by a postzygotic somatic point mutation in the male gonadal sex-determining locus (SRY): Molecular genetics and histological findings in a sporadic case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braun, A.; Kammerer, S.; Cleve, H.

1993-03-01

Recently, the gene for the determination of maleness has been identified in the sex-determining region on the short arm of the Y chromosome (SRY) between the Y-chromosomal pseudoautosomal boundary (PABY) and the ZFY gene locus. Experiments with transgenic mice confirmed that SRY is a part of the testis-determining factor (TDF). The authors describe a sporadic case of a patient with intersexual genitalia and the histological finding of ovotestes in the gonad, which resembles the mixed type of gonadal tissue without primordial follicle structures. The karyotype of the patient was 46,XY. By PCR amplification, they tested for the presence of SRYmore » by using DNA obtained from histological gonadal slices. The SRY products of both DNA preparations were further analyzed by direct sequencing. All three parts of the sex-determining region of the Y chromosome could be amplified from leukocytic DNA. The patient's and the father's SRY sequences were identical with the published sequence. In the SRY PCR product of gonadal DNA, the wild-type and two point mutations were present in the patient's sequence, simulating a heterozygous state of a Y-chromosomal gene: one of the mutations was silent, while the other encoded for a nonconservative amino acid substitution from leucine to histidine. Subcloning procedures showed that the two point mutations always occurred together. The origin of the patient's intersexuality is a postzygotic mutation of the SRY occurring in part of the gonadal tissue. This event caused the loss of the testis-determining function in affected cells. 37 refs., 6 figs.« less

Comparative Study of Reproductive Development in Wild and Captive-Reared Greater Amberjack Seriola dumerili (Risso, 1810)

PubMed Central

Zupa, Rosa; Rodríguez, Covadonga; Mylonas, Constantinos C.; Rosenfeld, Hanna; Fakriadis, Ioannis; Papadaki, Maria; Pérez, José A.; Pousis, Chrysovalentinos; Basilone, Gualtiero

2017-01-01

The greater amberjack Seriola dumerili is a large teleost fish with rapid growth and excellent flesh quality, whose domestication represents an ambitious challenge for aquaculture. The occurrence of reproductive dysfunctions in greater amberjack reared in captivity was investigated by comparing reproductive development of wild and captive-reared individuals. Wild and captive-reared breeders were sampled in the Mediterranean Sea during three different phases of the reproductive cycle: early gametogenesis (EARLY, late April-early May), advanced gametogenesis (ADVANCED, late May-early June) and spawning (SPAWNING, late June-July). Fish reproductive state was evaluated using the gonado-somatic index (GSI), histological analysis of the gonads and determination of sex steroid levels in the plasma, and correlated with leptin expression in the liver and gonad biochemical composition. The GSI and sex steroid levels were lower in captive-reared than in wild fish. During the ADVANCED period, when the wild greater amberjack breeders were already in spawning condition, ovaries of captive-reared breeders showed extensive atresia of late vitellogenic oocytes and spermatogenic activity ceased in the testes of half of the examined males. During the SPAWNING period, all captive-reared fish had regressed gonads, while wild breeders still displayed reproductive activity. Liver leptin expression and gonad proximate composition of wild and captive greater amberjack were similar. However, the gonads of captive-reared fish showed different total polar lipid contents, as well as specific lipid classes and fatty acid profiles with respect to wild individuals. This study underlines the need for an improvement in rearing technology for this species, which should include minimum handling during the reproductive season and the formulation of a specific diet to overcome the observed gonadal decrements of phospholipids, DHA (22:6n-3) and ARA (20:4n-6), compared to wild breeders. PMID:28056063

Incidence, Prevalence, Diagnostic Delay, and Clinical Presentation of Female 46,XY Disorders of Sex Development.

PubMed

Berglund, Agnethe; Johannsen, Trine H; Stochholm, Kirstine; Viuff, Mette H; Fedder, Jens; Main, Katharina M; Gravholt, Claus H

2016-12-01

The prevalence of phenotypic females with a 46,XY karyotype is low, thus current knowledge about age and clinical presentation at diagnosis is sparse even for the most frequent conditions, androgen insensitivity syndrome (AIS), and gonadal dysgenesis. To estimate incidence, prevalence, age at diagnosis, and clinical presentation at diagnosis in 46,XY females. A nationwide study covering all known females with a 46,XY karyotype in Denmark since 1960. The diagnosis of 46,XY disorder of sex development (DSD) was determined by medical record evaluation, data from the Danish National Patient Registry, and genetic testing, if available. A total of 166 females registered as 46,XY females in the Danish Cytogenetic Central Registry were identified. A total of 124 females were classified as having 46,XY DSD, 78 with AIS and 25 with gonadal dysgenesis, whereas the remaining subjects had a variety of different diagnoses. The prevalence of 46,XY females was 6.4 per 100 000 live born females, and for AIS and gonadal dysgenesis, it was 4.1 and 1.5 per 100 000, respectively. Median age at diagnosis was 7.5 years (95% confidence interval, 4.0-13.5; range, 0-34 y) in AIS and 17.0 years (95% confidence interval, 15.5-19.0; range, 0-28 y) in gonadal dysgenesis (P = .001). Clinical presentation was dependent on cause of DSD. The first estimate on prevalence of 46,XY females is 6.4 per 100 000 live born females. The presentation of AIS and gonadal dysgenesis is distinctly different, with AIS being diagnosed during childhood and gonadal dysgenesis during pubertal years. The presenting phenotype is dependent on the cause of 46,XY DSD.

Reproductive strategies and seasonal changes in the somatic indices of seven small-bodied fishes in Atlantic Canada in relation to study design for environmental effects monitoring.

PubMed

Barrett, Timothy J; Brasfield, Sandra M; Carroll, Leslie C; Doyle, Meghan A; van den Heuvel, Michael R; Munkittrick, Kelly R

2015-05-01

Small-bodied fishes are more commonly being used in environmental effects monitoring (EEM) studies. There is a lack of understanding of the biological characteristics of many small-bodied species, which hinders study designs for monitoring studies. For example, 72% of fish population surveys in Canada's EEM program for pulp and paper mills that used small-bodied fishes were conducted outside of the reproductive period of the species. This resulted in an inadequate assessment of the EEM program's primary effect endpoint (reproduction) for these studies. The present study examined seasonal changes in liver size, gonad size, and condition in seven freshwater and estuarine small-bodied fishes in Atlantic Canada. These data were used to examine differences in reproductive strategies and patterns of energy storage among species. Female gonadal recrudescence in all seven species began primarily in the 2-month period in the spring before spawning. Male gonadal development was concurrent with females in five species; however, gonadal recrudescence began in the fall in male three-spined stickleback (Gasterosteus aculeatus) and slimy sculpin (Cottus cognatus). The spawning period for each species was estimated from the decline in relative ovary size after its seasonal maximum value in spring. The duration of the spawning period reflected the reproductive strategy (single vs multiple spawning) of the species. Optimal sampling periods to assess reproductive impacts in each species were determined based on seasonal changes in ovary size and were identified to be during the prespawning period when gonads are developing and variability in relative gonad size is at a minimum.

Extracranial Germ Cell Tumors—Health Professional Version

Cancer.gov

Extracranial germ cell tumors (GCTs) arise from primordial germ cells, which migrate during embryogenesis from the yolk sac to the gonads. Childhood extracranial GCTs can be divided into the following two types: gonadal, and extragonadal. Find evidence-based information on extracranial germ cell tumors treatment.

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 ...

45,X/47,XXX/47,XX, del(Y)(p?)/46,XX mosaicism causing true hermaphroditism.

PubMed

Nieto, Karem; Peña, Rocío; Palma, Icela; Dorantes, Luis M; Eraña, Luis; Alvarez, Rebeca; García-Cavazos, Ricardo; Kofman-Alfaro, Susana; Queipo, Gloria

2004-10-15

Sex differentiation in humans depends on the presence of the Y-linked gene SRY, which is activated in the pre-Sertoli cells of the developing gonadal primordium to trigger testicular differentiation. Occasionally testicular formation can take place in subjects lacking a Y chromosome resulting in a 46,XX sex reversal condition. True hermaphroditism (TH) is a rare form of intersexuality characterized by the presence of testicular and ovarian tissue in the same individual. Genetic heterogeneity has been proposed as a cause of dual gonadal development in some cases and recently, hidden mosaicism was reported to cause TH in some 46,XX SRY negative patients. Here we report a TH case in which hidden mosaicism for the Y and X chromosome was detected by PCR and FISH in peripheral blood and gonadal tissue, supporting the fact that mosaicism may cause TH and that molecular analysis of gonadal tissue should be performed in all 46,XX cases.

The Distribution and Cellular Lineages of XX and XY Cells in Gonads Associated with Ovotesticular Disorder of Sexual Development.

PubMed

Nishina-Uchida, Noriko; Fukuzawa, Ryuji; Ishii, Tomohiro; Anaka, Matthew R; Hasegawa, Tomonobu; Hasegawa, Yukihiro

2016-01-01

Individuals with a 46,XX/46,XY karyotype are categorized as ovotesticular disorder of sexual development (ODSD) and have gonads with either an ovary on one side and a testis on the other side or a mixed ovotestis. To examine the distribution of 46,XX and 46,XY cells in gonads of 3 patients with ODSD, FISH for X and Y chromosomes and immunohistochemistry for SOX9 and FOXL2 were carried out. FISH analysis showed that XX signals were present in Sertoli cells in the seminiferous tubules, while cells containing Y signals were seen in epithelia of ovarian follicles. The immunolabeling of SOX9 and FOXL2 in the seminiferous tubules and ovarian follicles was mutually exclusive, irrespective of the presence of reversed sex chromosomes. We therefore suggest that the fate of individual gonadal epithelial cells is determined not only by the sex chromosomes but also by local environmental factors. © 2016 S. Karger AG, Basel.

Production, optimisation and characterisation of angiotensin converting enzyme inhibitory peptides from sea cucumber (Stichopus japonicus) gonad.

PubMed

Zhong, Chan; Sun, Le-Chang; Yan, Long-Jie; Lin, Yi-Chen; Liu, Guang-Ming; Cao, Min-Jie

2018-01-24

In this study, production of bioactive peptides with angiotensin converting enzyme (ACE) inhibitory activity from sea cucumber (Stichopus japonicus) gonad using commercial protamex was optimised by response surface methodology (RSM). As a result, the optimal condition to achieve the highest ACE inhibitory activity in sea cucumber gonad hydrolysate (SCGH) was hydrolysis for 1.95 h and E/S of 0.75%. For further characterisation, three individual peptides (EIYR, LF and NAPHMR) were purified and identified. The peptide NAPHMR showed the highest ACE inhibitory activity with IC 50 of 260.22 ± 3.71 μM. NAPHMR was stable against simulated gastrointestinal digestion and revealed no significant cytotoxicity toward Caco-2 cells. Molecular docking study suggested that Arg, His and Asn residues in NAPHMR interact with the S2 pocket or Zn 2+ binding motifs of ACE via hydrogen or π-bonds, potentially contributing to ACE inhibitory effect. Sea cucumber gonad is thus a potential resource to produce ACE inhibitory peptides for preparation of functional foods.

Characterization of lipids in three species of sea urchin.

PubMed

Zhou, Xin; Zhou, Da-Yong; Lu, Ting; Liu, Zhong-Yuan; Zhao, Qi; Liu, Yu-Xin; Hu, Xiao-Pei; Zhang, Jiang-Hua; Shahidi, Fereidoon

2018-02-15

Sea urchin gonad has been regarded as a "healthy" food. Although previous studies have suggested that sea urchin gonad might serve as a potential rich source of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) enriched phospholipid (PL), the molecular species profile of its PL has rarely been reported. In this study, about 200 molecular species of glycerophospholipid (GP), including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine and lysoglycerophosphoethanolamine, in gonads from three species of sea urchin (Glyptocidaris crenularis, Strongylocentrotus intermedius and Strongylocentrotus nudus) were characterized using tandem mass spectrometry. Most of the predominant GP molecular species contained PUFA, especially eicosapentaenoic acid (EPA). Meanwhile, the sea urchin lipids contained a high proportion of PL (39.45-50.30% of total lipids) and PUFA (34.47-46.56% of total FA). Among PL, phosphatidylcholine (67.88-72.58mol%) was dominant. Considering the high level of PUFA enriched GP, sea urchin gonads provide great potential as health-promoting food for human consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Fertility preservation in patients with hematological malignancies].

PubMed

Kanda, Yoshinobu

2015-03-01

Antineoplastic chemotherapy and irradiation affect gonadal function and may lead to infertility. Recovery of gonadal function is frequently observed after conventional chemotherapy in young patients with hematological malignancies, but conditioning regimens before hematopoietic stem cell transplantation result in permanent gonadal failure. Cryopreservation of sperm is effective for male patients, but it becomes difficult even after a single cycle of chemotherapy and therefore should be accomplished before starting chemotherapy. Embryo freezing after in vitro fertilization of harvested oocytes is an established method to preserve fertility in female patients. In addition, harvesting and freezing of unfertilized oocytes is also being evaluated in a clinical study. However, collection of good oocytes after chemotherapy is difficult. In addition, oocyte harvesting is an invasive procedure and may be associated with hemorrhage or infectious complications. Ovarian shielding during total body irradiation allows ovary preservation in most female patients, but this cannot be performed in patients with active malignancies. Strategies for gonadal function preservation should be planned before starting treatment for hematological malignancies.

Reproductive strategy of the Patagonian catfish Hatcheria macraei.

PubMed

Chiarello-Sosa, J M; Battini, M A; Barriga, J P

2016-09-01

This study describes the reproductive strategy of the stream-dwelling catfish Hatcheria macraei in the Pichileufu River, Argentina. Gonad maturity phases, classified on the basis of histological analysis, stages of gamete development and the frequency distribution of oocyte size, were correlated with macroscopic features of the gonads. Hatcheria macraei has a cystovarian ovary, asynchronous oocyte development and lobular testes. Five oocyte and four spermatogenic stages were identified and related to macroscopic gonad characteristics, making it possible to divide gonad development into five phases for females and males. Mature oocyte diameter ranged from 922 to 1935 µm. Absolute fecundity in mature females varied from 115 to 480 oocytes. Hatcheria macraei has multiple spawning during a protracted reproductive season that extends from December to April. This, together with its small size, is characteristic of an opportunistic reproductive strategy, commonly found in species that inhabit adverse and unpredictable environments, such as the low-order rivers of Patagonia. © 2016 The Fisheries Society of the British Isles.

A gonad-expressed opsin mediates light-induced spawning in the jellyfish Clytia

PubMed Central

Quiroga Artigas, Gonzalo; Lapébie, Pascal; Leclère, Lucas; Takeda, Noriyo; Deguchi, Ryusaku; Jékely, Gáspár

2018-01-01

Across the animal kingdom, environmental light cues are widely involved in regulating gamete release, but the molecular and cellular bases of the photoresponsive mechanisms are poorly understood. In hydrozoan jellyfish, spawning is triggered by dark-light or light-dark transitions acting on the gonad, and is mediated by oocyte maturation-inducing neuropeptide hormones (MIHs) released from the ectoderm. We determined in Clytia hemisphaerica that blue-cyan light triggers spawning in isolated gonads. A candidate opsin (Opsin9) was found co-expressed with MIH within specialised ectodermal cells. Opsin9 knockout jellyfish generated by CRISPR/Cas9 failed to undergo oocyte maturation and spawning, a phenotype reversible by synthetic MIH. Gamete maturation and release in Clytia is thus regulated by gonadal photosensory-neurosecretory cells that secrete MIH in response to light via Opsin9. Similar cells in ancestral eumetazoans may have allowed tissue-level photo-regulation of diverse behaviours, a feature elaborated in cnidarians in parallel with expansion of the opsin gene family. PMID:29303477

[Transsexualism as a clinical symptom of true hermaphroditism].

PubMed

Derevianko, I M; Derevianko, T I; Abdul'menov, R R

2008-01-01

Transsexualism is incorrectly thought to be a disease of sexual centers (zones) of the brain but these sexual centers in the brain operate only in response to action of sexual hormones (androgens or estrogens) which are produced in the gonads and delivered to the brain by blood. In hermaphroditism the brain receives both androgens and estrogens. Transsexualism syndrome develops in cases when all sexual organs develop under the influence of one sex while sexual psychoorientation, sexual autoidentification and sexual behavior form under the influence of hormones of the other sex. Therefore, treatment of this syndrome should not consist of surgical correction of the sex according to psychic behavior of the patient but should be directed to detection of the gonad (or gonadal tissue) causing abnormal behavior and its removal. Gonad corresponding to sexual organs of the patient should be preserved. Of 19 patients with true hermaphroditism and 199 patients with false hermaphroditism observed by the authors 4 patients with true hermaphroditism had transsexualism.

Molecular and morphological differentiation of testes and ovaries in relation to the thermosensitive period of gonad development in the snapping turtle, Chelydra serpentina.

PubMed

Rhen, Turk; Fagerlie, Ruby; Schroeder, Anthony; Crossley, Dane A; Lang, Jeffrey W

2015-01-01

Ambient temperatures during embryonic development determine gonadal sex in many reptiles. The temperature sensitive period for sex determination has been defined by shifting eggs between female- and male-producing temperatures in a few species. This phase spans 20-35% of embryogenesis in most species, which makes it difficult to define the mechanisms that transduce temperature into a signal for ovarian versus testicular development. We present an extensive set of studies that define a brief period when high temperature specifies, and then determines, ovarian fate in a northern population of snapping turtles, Chelydra serpentina. We shifted embryos from male to female temperatures, or vice versa, at various stages of development. Gonads in embryos incubated at female temperatures commit to ovarian fate earlier (by stage 18) than gonads in embryos incubated at male temperatures commit to testicular fate (by stages 19-21). In double shift studies, embryos were incubated at a female temperature, exposed to a male temperature for set times, and shifted back to the original temperature, or vice versa. The time required to induce ovarian development (≤6 days at female temperatures) was much shorter than the time required to induce testicular formation (>20 days at male temperatures). Differentiation of the gonads at the histological level occurred after the sex-determining period. Nevertheless, we found that a change in temperature rapidly (within 24h) influenced expression and splicing of WT1 mRNA: the absolute abundance of WT1 mRNA, the relative abundance of +KTS versus -KTS isoforms, as well as the ratio of +KTS:-KTS isoforms was higher in gonads at a male versus a female temperature. In conclusion, ovarian fate is more readily determined than testicular fate in snapping turtle embryos. The short sex-determining period in this species (6-8% of embryogenesis) will facilitate studies of molecular mechanisms for specification and determination of gonad fate by temperature. Copyright © 2015 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

Method for observation of deembedded sections of fish gonad by scanning electron microscopy

NASA Astrophysics Data System (ADS)

Mao, Lian-Ju

2000-09-01

This article reports a method for examining the intracellular structure of fish gonads using a scanning electron microscope(SEM). The specimen preparation procedure is similar to that for transmission electron microscopy wherein samples cut into semi-thin sections are fixed and embedded in plastic. The embedment matrix was removed by solvents. Risen-free specimens could be observed by SEM. The morphology of matured sperms in the gonad was very clear, and the oocyte internal structures appeared in three-dimensional images. Spheroidal nucleoli and yolk vesicles and several bundles of filaments adhered on the nucleoli could be viewed by SEM for the first time.

vasa is expressed in somatic cells of the embryonic gonad in a sex-specific manner in Drosophila melanogaster.

PubMed

Renault, Andrew D

2012-10-15

Vasa is a DEAD box helicase expressed in the Drosophila germline at all stages of development. vasa homologs are found widely in animals and vasa has become the gene of choice in identifying germ cells. I now show that Drosophila vasa expression is not restricted to the germline but is also expressed in a somatic lineage, the embryonic somatic gonadal precursor cells. This expression is sexually dimorphic, being maintained specifically in males, and is regulated post-transcriptionally. Although somatic Vasa expression is not required for gonad coalescence, these data support the notion that Vasa is not solely a germline factor.

Stem Cells in Mammalian Gonads.

PubMed

Wu, Ji; Ding, Xinbao; Wang, Jian

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.

Effects of larval-juvenile treatment with perchlorate and co-treatment with thyroxine on zebrafish sex ratios

USGS Publications Warehouse

Mukhi, S.; Torres, L.; Patino, R.

2007-01-01

The objective of this study was to determine the effect of larval-juvenile exposure to perchlorate, a thyroid hormone synthesis inhibitor, on the establishment of gonadal sex ratios in zebrafish. Zebrafish were exposed to untreated water or water containing perchlorate at 100 or 250 ppm for a period of 30 days starting at 3 days postfertilization (dpf). Recovery treatments consisted of a combination of perchlorate and exogenous thyroxine (T4; 10 nM). Thyroid histology was assessed at the end of the treatment period (33 dpf), and gonadal histology and sex ratios were determined in fish that were allowed an additional 10-day period of growth in untreated water. As expected, exposure to perchlorate caused changes in thyroid histology consistent with hypothyroidism and these effects were reversed by co-treatment with exogenous T4. Perchlorate did not affect fish survival but co-treatment with T4 induced higher mortality. However, relative to the corresponding perchlorate concentration, co-treatment with T4 caused increased mortality only at a perchlorate concentration of 100 ppm. Perchlorate alone or in the presence of T4 suppressed body length at 43 dpf relative to control values. Perchlorate exposure skewed the sex ratio toward female in a concentration-dependent manner, and co-treatment with T4 not only blocked the feminizing effect of perchlorate but also overcompensated by skewing the sex ratio towards male. Moreover, co-treatment with T4 advanced the onset of spermatogenesis in males. There was no clear association between sex ratios and larval survival or growth. We conclude that endogenous thyroid hormone plays a role in the establishment of gonadal sex phenotype during early development in zebrafish. ?? 2006 Elsevier Inc. All rights reserved.

Modulation of steroidogenesis and estrogen signalling in the estuarine killifish (Fundulus heteroclitus) exposed to ethinylestradiol.

PubMed

Hogan, Natacha S; Currie, Suzanne; LeBlanc, Sacha; Hewitt, L Mark; MacLatchy, Deborah L

2010-06-10

Previous studies have shown that mummichog (Fundulus heteroclitus; a lunar, asynchronous-spawning killifish of the western Atlantic) exposed to 17alpha-ethynylestradiol (EE2) exhibit decreased plasma reproductive steroid levels, decreased gonadal steroid production, increased plasma vitellogenin, decreased fecundity and impaired fertilization. The objective of this study was to determine the potential mechanisms by which EE2 depresses gonadal steroidogenesis and influences estrogen signalling in the mummichog. Adult recrudesced fish were exposed to the potent synthetic estrogen, ethinylestradiol (EE2; 0-270ng/L) for 14 days. Following exposure, gonadal tissue was removed and incubated for 24h with stimulators of steroidogenesis, including forskolin; 25-OH cholesterol; or pregnenolone. Testosterone production was decreased in basal, forskolin-stimulated and pregnenolone-stimulated EE2-exposed males, indicating effects on the steroidogenic pathway both at and downstream of cholesterol mobilization to P450 side-chain cleavage (P450scc) and/or P450scc conversion of cholesterol to pregnenolone. Hepatic transcript levels of estrogen receptor alpha (ERalpha) and vitellogenin were increased in EE2-treated males compared to control recrudescing males and females confirming an estrogenic response. Hepatic heat shock protein 90 (Hsp90), a chaperoning molecule involved in estrogen signalling, was not affected by EE2 exposure at either the transcript or protein level. However, higher levels of Hsp90 observed in the membrane fractions of female fish raise interesting questions regarding the influence of gender on Hsp90's role in estrogen signalling. These results demonstrate that EE2 can alter steroid production at specific sites within the steroidogenic pathway and can stimulate hepatic estrogen signalling, providing important information regarding the molecular mechanisms underlying the endocrine response of the mummichog to exogenous estrogen.

Exploiting genomic data to identify proteins involved in abalone reproduction.

PubMed

Mendoza-Porras, Omar; Botwright, Natasha A; McWilliam, Sean M; Cook, Mathew T; Harris, James O; Wijffels, Gene; Colgrave, Michelle L

2014-08-28

Aside from their critical role in reproduction, abalone gonads serve as an indicator of sexual maturity and energy balance, two key considerations for effective abalone culture. Temperate abalone farmers face issues with tank restocking with highly marketable abalone owing to inefficient spawning induction methods. The identification of key proteins in sexually mature abalone will serve as the foundation for a greater understanding of reproductive biology. Addressing this knowledge gap is the first step towards improving abalone aquaculture methods. Proteomic profiling of female and male gonads of greenlip abalone, Haliotis laevigata, was undertaken using liquid chromatography-mass spectrometry. Owing to the incomplete nature of abalone protein databases, in addition to searching against two publicly available databases, a custom database comprising genomic data was used. Overall, 162 and 110 proteins were identified in females and males respectively with 40 proteins common to both sexes. For proteins involved in sexual maturation, sperm and egg structure, motility, acrosomal reaction and fertilization, 23 were identified only in females, 18 only in males and 6 were common. Gene ontology analysis revealed clear differences between the female and male protein profiles reflecting a higher rate of protein synthesis in the ovary and higher metabolic activity in the testis. A comprehensive mass spectrometry-based analysis was performed to profile the abalone gonad proteome providing the foundation for future studies of reproduction in abalone. Key proteins involved in both reproduction and energy balance were identified. Genomic resources were utilised to build a database of molluscan proteins yielding >60% more protein identifications than in a standard workflow employing public protein databases. Copyright © 2014 Elsevier B.V. All rights reserved.

Long-Term Recordings of Arcuate Nucleus Kisspeptin Neurons Reveal Patterned Activity That Is Modulated by Gonadal Steroids in Male Mice.

PubMed

Vanacker, Charlotte; Moya, Manuel Ricu; DeFazio, R Anthony; Johnson, Michael L; Moenter, Suzanne M

2017-10-01

Pulsatile release of gonadotropin-releasing hormone (GnRH) is key to fertility. Pulse frequency is modulated by gonadal steroids and likely arises subsequent to coordination of GnRH neuron firing activity. The source of rhythm generation and the site of steroid feedback remain critical unanswered questions. Arcuate neurons that synthesize kisspeptin, neurokinin B, and dynorphin (KNDy) may be involved in both of these processes. We tested the hypotheses that action potential firing in KNDy neurons is episodic and that gonadal steroids regulate this pattern. Targeted extracellular recordings were made of green fluorescent protein-identified KNDy neurons in brain slices from adult male mice that were intact, castrated, or castrated and treated with estradiol or dihydrotestosterone (DHT). KNDy neurons exhibited marked peaks and nadirs in action potential firing activity during recordings lasting 1 to 3.5 hours. Peaks, identified by Cluster analysis, occurred more frequently in castrated than intact mice, and either estradiol or DHT in vivo or blocking neurokinin type 3 receptor in vitro restored peak frequency to intact levels. The frequency of peaks in firing rate and estradiol regulation of this frequency is similar to that observed for GnRH neurons, whereas DHT suppressed firing in KNDy but not GnRH neurons. We further examined the patterning of action potentials to identify bursts that may be associated with increased neuromodulator release. Burst frequency and duration are increased in castrated compared with intact and steroid-treated mice. The observation that KNDy neurons fire in an episodic manner that is regulated by steroid feedback is consistent with a role for these neurons in GnRH pulse generation and regulation. Copyright © 2017 Endocrine Society.

Contextual amplification or attenuation of the impact of pubertal timing on Mexican-origin boys' mental health symptoms.

PubMed

White, Rebecca M B; Deardorff, Julianna; Liu, Yu; Gonzales, Nancy A

2013-12-01

To examine the role of neighborhood contextual variation in the putative association between pubertal timing and internalizing and externalizing symptoms among Mexican-origin boys. In a sample of seventh-grade Mexican-origin boys (N = 353; x¯age=12.8years) we assessed a range of secondary sexual characteristics, internalizing, and externalizing symptoms. Reports on all secondary sexual characteristics were collapsed and age-standardized to represent total pubertal timing. We also distinguished between the timing of physical changes driven by adrenal versus gonadal maturation. Boys' residential addresses were geocoded and American Community Survey data were used to describe neighborhoods along two dimensions: ethnic concentration and socioeconomic disadvantage. Three years later (in 10th grade) we re-assessed internalizing and externalizing symptoms. We examined the moderating influence of neighborhood ethnic concentration and neighborhood socioeconomic disadvantage on the prospective associations between puberty timing (total, gonadal, adrenal) and internalizing and externalizing symptoms. Earlier total pubertal timing predicted increases in externalizing symptoms, but only when Mexican-origin boys lived in neighborhoods low on ethnic concentration. Total timing results for externalizing symptoms were replicated for adrenal timing. Furthermore, early adrenal timing predicted increases in internalizing symptoms, but again, only when boys lived in neighborhoods low on ethnic concentration. No effects were observed for gonadal timing specifically. Early pubertal timing, especially advanced physical changes initiated and regulated by adrenal maturation, have important implications for Mexican-origin boys' internalizing and externalizing symptoms, but these implications depend on neighborhood characteristics. Ethnically concentrated neighborhoods are protective for early-maturing Mexican-origin boys. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Molecular cloning and characterization of amh, dax1 and cyp19a1a genes and their response to 17α-methyltestosterone in Pengze crucian carp.

PubMed

Li, Meng; Wang, Lihong; Wang, Houpeng; Liang, Hongwei; Zheng, Yao; Qin, Fang; Liu, Shaozhen; Zhang, Yingying; Wang, Zaizhao

2013-05-01

The proteins encoded by amh, dax1 and cyp19a1a play important roles in gonad differentiation. Their functions have been far less studied in teleosts. In this study, the full-length cDNAs of amh, dax1 and cyp19a1a were cloned and characterized in a triploid gynogenic fish, the Pengze crucian carp. Their expression profilings in juvenile development, adult tissues and juveniles exposed to 100 ng/L 17α-methyltestosterone (MT) were investigated. Results showed that their putative proteins shared high identities to their counterparts in cyprinid fish species, respectively. The tissue distribution results indicated that amh and cyp19a1a were predominantly expressed in the ovary and dax1 was dominantly expressed in the liver. Gene profiling in the developmental stages showed that all the three target genes had a consistent highest expression at 48 days post hatching (dph). The period of 48 dph appeared to be a key time during the process of the gonad development of Pengze crucian carp. 100 ng/L MT significantly increased the mRNA expression of amh at 2- and 4-week exposures and enhanced dax1 and cyp19a1a at 6-week exposure. The present study indicated that MT could influence the gonad development in Pengze crucian carp by disturbing sex-differentiation associated gene expression. Furthermore, the present study will be of great significance to broaden the understanding of molecular mechanisms of the physiological processes of reproduction in fish. Copyright © 2013 Elsevier Inc. All rights reserved.

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...

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 (...

Influence of Xenorhabdus (Gamma-Proteobacteria: Enterobacteriaceae) symbionts on gonad postembryonic development in Steinernema (Nematoda: Steinernematidae) nematodes.

PubMed

Roder, Alexandra C; Stock, S Patricia

2018-03-01

Steinernema nematodes and their Xenorhabdus partners form an obligate mutualistic association. This partnership is insecticidal to a wide range of insects. Steinernema rely on their Xenorhabdus partner to produce toxins inside the insect cadaver to liberate nutrients from the insect, as well as antimicrobials to sterilize the cadaver, thus creating a suitable environment for reproduction. In return, Steinernema vector their Xenorhabdus between insect hosts. Disruption of this partnership may affect the success of both partners. For instance, when Steinernema associates with non-cognate symbionts, their virulence and reproductive fitness are affected. In this study, we examined the effect of symbiotic (cognate and non-cognate) and non-symbiotic bacteria on maturation time, gonad postembryonic development, and sex ratio of first-generation Steinernema adults. Two Steinernema spp. were considered: S. feltiae SN and S. carpocapsae All. In vitro assays were carried out by pairing each nematode sp. with symbiotic (cognate and non-cognate) Xenorhabdus, and with non-symbiotic bacteria (Serratia proteamaculans). Additionally, for comparative purposes, we also considered adult nematodes reared in vivo in Galleria mellonella larvae to assess nematode development under natural conditions. Results from this study showed non-symbiotic Serratia proteamaculans did not support adult development of S. feltiae but it allowed development of S. carpocapsae adults. Sex ratio decreased from 2:1 to 1:1 (female: male) when S. carpocapsae adults were reared with the non-symbiotic S. proteamaculans. Cognate or non-cognate Xenorhabdus spp. and/or strains did not change the sex ratio of any of either Steinernema spp. tested. Morphometric analysis also revealed that bacterial conditions influenced adult size and gonad postembryonic development in both Steinernema species. Body size (length and width), and gonad length in both S. feltiae males and females, were significantly reduced when reared with a non-cognate Xenorhabdus species. In S. carpocapsae, males exhibited an enhanced body size (length and width) and gonad length when reared with a non-cognate X. nematophila strain. S. carpocapsae females also exhibited an enhanced gonad length when reared with a non-cognate X. nematophila strain. S. carpocapsae males and females were underdeveloped when reared with the non-symbiotic S. proteamaculans, and exhibited reduced body sizes and gonad lengths. We conclude that development of first-generation adults of both Steinernema spp. tested, in particular time to adult maturation as well as body and gonad size were directly influenced by the bacterial symbionts they were cultured with. However, response to the culture conditions was species specific. Published by Elsevier Inc.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Recreational Drug Ecstasy Disrupts the Hypothalamic-Pituitary-Gonadal Reproductive Axis in Adult Male Rats

PubMed Central

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

2009-01-01

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 (HPG) reproductive axis of male rats. Adult male Sprague-Dawley rats self-administered saline or MDMA or saline either once (acute) or for 20 days (chronic), and were euthanized 7 days following last administration. We quantified hypothalamic GnRH mRNA, serum luteinizing hormone (LH) 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 HPG 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. PMID:18309234

Effect of dietary administration of letrozole and tamoxifen on gonadal development, sex differentiation and biochemical changes in common carp (Cyprinus carpio L.).

PubMed

Singh, Atul K; Srivastava, P P; Verma, Rita; Srivastava, Sharad C; Kumar, Dinesh; Ansari, Abubakar

2015-03-01

The effect of letrozole and tamoxifen on the specific growth rate (SGR; % day(-1)), gonado-somatic index (GSI), total haemoglobin (g%), gonadal and serum protein as well as lipid, sex differentiation and 17β-oestradiol levels were studied in sexually undifferentiated Cyprinus carpio fingerlings 30 days post fertilisation (30 dpf) for 60 days. Results showed decreased GSI with tamoxifen treatment whereas letrozole increased it. There were reduced protein, lipid, triglyceride and cholesterol levels after treatment with tamoxifen and letrozole during gonadal development. Tamoxifen (200mgkg(-1) feed) induced 82.5% masculinisation, whereas letrozole in the same dose produced 98.5% males. Gonadal 17β-oestradiol significantly declined from 86.0±1.41pg per 100mg (control) to 45.5±1.94pg per 100mg with tamoxifen and 36.0±0.72pg per 100mg with letrozole treatment. Similarly, serum 17β-oestradiol levels also decreased after tamoxifen and letrozole treatments. Testicular development in 37.8% of fish treated with tamoxifen and letrozole was found to be more advanced (spermatocytes) than in the control (spermatogonium); however, there was reduced ovarian growth and increased atresia. It was concluded that letrozole and tamoxifen both significantly affect sex differentiation and gonadal maturity in C. carpio leading to the production of sex-reversed males, yet the effect of letrozole was more potent.

Function of the hypothalamic-pituitary-gonadal axis in long-term survivors of hematopoietic stem cell transplantation for hematological diseases.

PubMed

Somali, Maria; Mpatakoias, Vassilios; Avramides, Avraam; Sakellari, Ioanna; Kaloyannidis, Panayotis; Smias, Christos; Anagnostopoulos, Achilleas; Kourtis, Anargyros; Rousso, David; Panidis, Dimitrios; Vagenakis, Apostolos

2005-07-01

Gonadal dysfunction in adult long-term survivors of hematopoietic stem cell transplantation (HSCT) is an adverse effect of conditioning regimens consisting of chemotherapy and total body irradiation (TBI). The impact of conditioning regimens consisting of chemotherapy alone on the function of the hypothalamic-pituitary-gonadal (HPG) axis was evaluated in a series of 41 female and 31 male patients who had undergone either autologous or allogeneic bone marrow/peripheral blood stem cell transplantation; mean age at transplantation was 32.6 years and mean time interval from transplantation was 1.5 years (range 0.2-9.8 years). Provocative testing of the HPG axis by administration of luteinizing hormone-releasing hormone was included in the first endocrinological evaluation. The follow-up period extended to three consecutive years. Gonadal dysfunction was not reported by any of the patients prior to their underlying illness. Hypergonadotrophic hypogonadism was observed in 97% of female and 19% of male patients. Leydig cell strain (normal testosterone, high luteinizing hormone levels) was evident in 32% and spermatogenesis damage (high follicle-stimulating hormone levels) in 68% of the male population. At the conclusion of the study four women (10%) had regained spontaneous menses and all hypogonadal men had resumed normal testosterone levels. Our results indicate a high incidence of gonadal dysfunction due to target organ failure in HSCT recipients not treated by TBI.

Attempt to rescue sex-reversal by transgenic expression of the PISRT1 gene in XX PIS-/- goats.

PubMed

Boulanger, L; Kocer, A; Daniel, N; Pannetier, M; Chesné, P; Heyman, Y; Renault, L; Mandon-Pépin, B; Chavatte-Palmer, P; Vignon, X; Vilotte, J-L; Cotinot, C; Renard, J-P; Pailhoux, E

2008-01-01

The Polled Intersex Syndrome (PIS mutation) in goats leads to an absence of horn and to an early sex-reversal of the XX gonads. This mutation is a deletion of an 11.7-kb DNA fragment showing a tissue-specific regulatory activity. Indeed, in XX PIS(-/-) gonads the deletion of PIS leads to the transcriptional extinction of at least 3 neighboring genes, FOXL2, PFOXic and PISRT1. Among them, only FOXL2 is a 'classical' gene, encoding a highly conserved transcription factor. On the other hand, knock-out of Foxl2 in mice results in an early blocking of follicle formation without sex-reversal. This phenotype discrepancy leads to two hypotheses, either FOXL2 is responsible for XX sex-reversal in goat assuming distinct functions of its protein during ovarian differentiation in different mammals, or other PIS-regulated genes are involved. To assess the second possibility, PISRT1 expression was constitutively restored in XX PIS(-/-) gonads. Six transgenic fetuses were obtained by nuclear transfer and studied at 2 developmental stages, 41 and 46 days post-reconstruction. The gonads of these fetuses appear phenotypically identical to those of cloned non-transgenic controls. Conclusively, this result argues for FOXL2 being responsible for the PIS gonad-associated phenotype. Its invalidation in goat will help to better understand this complex syndrome. Copyright 2008 S. Karger AG, Basel.

Reproduction of the giant jellyfish, Nemopilema nomurai (Scyphozoa: Rhizostomeae), in 2006-2008 as peripherally-transported populations

NASA Astrophysics Data System (ADS)

Iguchi, Naoki; Lee, Hye Eun; Yoon, Won Duk; Kim, Suam

2010-06-01

This study investigated the sexual maturation process, release of spermatozoa or eggs and oocyte diameter of the rhizostomid medusae Nemopilema nomurai using samples collected from August 2006 to June 2008 from the waters around Korea and Japan, including peripheral areas outside the species’ usual habitat. Immature medusae were observed from June to October only in the western sector of the study area. The onset of spermatozoa and egg release occurred in September and October, respectively, and peaked in December and January. Medusae migrated eastward from source areas with the Tsushima Warm Current, where they formed gametes and spawned. Peak position and maximum oocyte diameter increased as the gonads developed according to the size-frequency distribution of oocytes. No fertilized eggs or embryos were found in the gonads. The correlation was analyzed with bell diameter, maximum oocyte diameter, sampling date, surface water temperature and gonad color to estimate which environmental factors and maturation indices were related to the maturation stage of females. Maturation stage correlated well with maximum oocyte diameter, which correlated negatively with surface water temperature. There was no significant correlation between bell diameter and maturation stage. Therefore, bell diameter was inappropriate for determining maturation index. Sex could not be distinguished clearly by gonad color. However, light pink gonads were more prevalent in males and various deep colors such as orange and brown were more frequent in female medusae.

Unraveling estradiol metabolism and involvement in the reproductive cycle of non-vertebrate animals: The sea urchin model.

PubMed

Silvia, Mercurio; Paolo, Tremolada; Nobile, Maria; Denise, Fernandes; Cinta, Porte; Michela, Sugni

2015-12-01

Estradiol (E2) is a well-known hormone in vertebrates whereas in invertebrates its unambiguous presence was verified only in some species. Weather this presence is also associated to similarly conserved roles in animal phylogeny is similarly uncertain. Due to their phylogenetic position, echinoderms represent ideal experimental models to provide evolutionary insights into estrogen appearance and function. Therefore, in this research, we investigated if E2 is truly present and has a role in the reproductive biology of the sea urchin Paracentrotus lividus. Presence of 17β estradiol in body fluids was confirmed by liquid chromatography-mass spectrometry. By immunological methods (RIA) we evaluated the physiological circulating E2 levels of adult specimens and, on the basis of these, we directly administered E2 to study its metabolism and its putative effects on gonad development at physiological doses. Although different E2 tested concentrations, a correspondent dose-dependent increase of hormone levels was not found in both body fluids and gonads, suggesting the presence of potent homeostatic/detoxification mechanisms. These latter do not involve enzymes such as aromatase-like, sulfotransferase-like and acyltransferase-like, whose activities were not affected by E2 administration. Despite the increase of endogenous E2, the treatment did not induce significant variations in none of the considered reproductive parameters. Overall, this research (1) provides definitive evidence of E2 presence in sea urchin tissues and (2) demonstrate that, differently from vertebrates and starfish, E2 does not play a key role in sea urchins reproductive processes. Intra-phylum differences suggest the existence of class-specific hormonal mechanisms and highlight the risk of Phylum generalization. Copyright © 2015 Elsevier Inc. All rights reserved.

Molecular cloning and characterization of SoxB2 gene from Zhikong scallop Chlamys farreri

NASA Astrophysics Data System (ADS)

He, Yan; Bao, Zhenmin; Guo, Huihui; Zhang, Yueyue; Zhang, Lingling; Wang, Shi; Hu, Jingjie; Hu, Xiaoli

2013-11-01

The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop ( Chlamys farreri), and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 ( Cf SoxB2) were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group (HMG) box. The full-length cDNA sequence of Cf SoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of Cf SoxB 2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of Cf SoxB2 were similar. Considering the specific expression and roles of SoxB 2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for Sox B 2 in C. farreri.

Human low density lipoprotein as a substrate for in vitro steroidogenesis assays with fathead minnow ovary explants

EPA Science Inventory

Gonad explant in vitro steroidogenesis assays are used as part of a multifaceted strategy to detect endocrine active chemicals capable of altering steroid hormone synthesis. An in vitro steroidogenesis assay used in our laboratory involves exposing fathead minnow (FHM) gonad exp...

POTENTIAL ALTERATIONS IN GENE EXPRESSION ASSOCIATED WITH CARCINOGEN EXPOSURE IN MYA ARENARIA

EPA Science Inventory

Gonadal cancers in soft-shell clams (Mya arenaria) have been found at high prevalences (20-40%) in populations in eastern Maine. The aetiology of these tumours is unknown. We hypothesized that gene expression would be altered in gonadal tumours and that examination of gene expres...

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 (...

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 ...

Inhibitory effects of homeodomain-interacting protein kinase 2 on the aorta-gonad-mapharsen hematopoiesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohtsu, Naoki; Nobuhisa, Ikuo; Mochita, Miyuki

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 HIPK2more » 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.« less

A rare case of 46,XX gonadal dysgenesis and Mayer-Rokitansky-Kuster-Hauser syndrome.

PubMed

Manne, Sriharibabu; Veeraabhinav, C H; Jetti, Mounica; Himabindu, Yalamanchali; Donthu, Kiranmai; Badireddy, Mutyalarayudu

2016-01-01

46,XX gonadal dysgenesis is a rare genetically heterogeneous disorder characterized by underdeveloped ovaries with consequent, impuberism, primary amenorrhea, and hypergonadotropic hypogonadism. Mullerian agenesis or Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome is characterized by congenital aplasia of the uterus and the upper part (2/3) of the vagina in a woman with normal development of secondary sexual characteristics and a normal 46,XX karyotype. The phenotypic manifestations of MRKH syndrome may sometimes overlap with various other syndromes and require accurate delineation. The coexistence of both these disorders is extremely rare. Here, we report a case of 46,XX gonadal dysgenesis and MRKH syndrome with anatomically dispersed congenital anomalies unique among reported cases.

Ovarian Gonadoblastoma with Dysgerminoma in a Young Girl with 46, XX Karyotype: A Case Report

PubMed Central

Kanagal, Deepa V; Prasad, Kishan; Rajesh, Aparna; Kumar, Rohan G; Cherian, Sara; Shetty, Harish; Shetty, Prasanna Kumar

2013-01-01

Gonadoblastoma is a rare gonadal tumour consisting of a mixture of germ cells and sex cord stromal derivatives resembling immature granulosa and Sertoli cells. It usually arises in various types of gonadal dysgenesis containing Y chromosome like pure or mixed gonadal dysgenesis. Occurrence in phenotypically and chromosomally normal women is very rare. We report here a case of gonadoblastoma with dysgerminoma in a 14–years–old girl who presented with a huge tumour, virilisation and normal 46XX karyotype. Association of dysgerminoma is seen in 50% cases of gonadoblastomas. Elevated tumour markers like hCG and alpha Fetoprotein may make the diagnosis challenging. PMID:24179931

vasa is expressed in somatic cells of the embryonic gonad in a sex-specific manner in Drosophila melanogaster

PubMed Central

Renault, Andrew D.

2012-01-01

Summary Vasa is a DEAD box helicase expressed in the Drosophila germline at all stages of development. vasa homologs are found widely in animals and vasa has become the gene of choice in identifying germ cells. I now show that Drosophila vasa expression is not restricted to the germline but is also expressed in a somatic lineage, the embryonic somatic gonadal precursor cells. This expression is sexually dimorphic, being maintained specifically in males, and is regulated post-transcriptionally. Although somatic Vasa expression is not required for gonad coalescence, these data support the notion that Vasa is not solely a germline factor. PMID:23213382

Computational Model of the Fathead Minnow Hypothalamic-Pituitary-Gonadal Axis: Incorporating Protein Synthesis in Improving Predictability of Responses to Endocrine Active Chemicals

EPA Science Inventory

There is international concern about chemicals that alter endocrine system function in humans and/or wildlife and subsequently cause adverse effects. We previously developed a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minno...

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

[Ovarian gonadal tumors in materials of the clinic of gynecological endocrinology of the Medical Academy in Poznań (1970-1998)].

PubMed

Warenik-Szymankiewicz, A; Słopień, R; Kedzia, H; Grotowski, W

1999-05-01

11 patients with ovarian gonadal tumors were treated at Clinic of Endocrinological-Gynecology of Academy of Medicine in Poznań. All presented symptoms of hormonal ovetproduction. In 9 cases we performed adnexectomy, only in 1 case (patient after menopause) hysterectomy with bilateral adnexectomy.

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.

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...

DISTRIBUTION OF MERCURY IN THE TISSUES OF FIVE SPECIES OF FRESHWATER FISH FROM LAKE MEAD, USA

EPA Science Inventory

Total mercury (Hg) concentrations were determined in seven tissues (skeletal muscle, liver,
blood, gonad, brain, gill, and heart) of 59 striped bass and four tissues (muscle, liver, blood, and
gonad) of 69 largemouth bass, 76 channel catfish, 12 bluegill, and 22 blue tila...

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...

Computational Modeling of Hypothalamic-Pituitary-Gonadal Axis to Predict Adaptive Responses in Female Fathead Minnows Exposed to an Aromatase Inhibitor

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...

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...

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...

Cyclophosphamide-induced male subfertility in mice: An assessment of the potential benefits of Maca supplement.

PubMed

Onaolapo, A Y; Oladipo, B P; Onaolapo, O J

2018-04-01

Effects of Lepidium meyenii (Maca) on cyclophosphamide (CYP)-induced gonadal toxicity in male mice were investigated. Mice were assigned to six treatment groups: Vehicle control, CYP control, CYP plus oral Maca (500 or 1,000 mg/kg), and oral Maca (500 or 1,000 mg/kg). CYP was administered via the intraperitoneal route (days 1-2), while vehicle or Maca were administered daily for 28 days. On day 28, half of the animals in each group were either sacrificed or paired with age-matched females for fertility assessment. Plasma testosterone assay, sperm analysis and assessment of tissue antioxidant/morphological status were also carried out. CYP administration was associated with oxidative stress, subfertility and morphometric/morphological indices of gonadal injury, while administration of Maca mitigated CYP-induced gonadal toxicity and subfertility. This study shows that Maca is beneficial in the mitigation of CYP-induced male gonadal insufficiency and/or testicular morphological changes; however, further studies will be needed to ascertain its usability for this purpose in humans. © 2017 Blackwell Verlag GmbH.

Reproductive characteristics of the humbug damselfish, Dascyllus aruanus, in Chuuk Lagoon, Micronesia

NASA Astrophysics Data System (ADS)

Choi, Young-Ung; Park, Miae; Lee, Kyun-Woo; Oh, Chulhong; Park, Heung-Sik

2014-12-01

This study was conducted to investigate the reproductive characteristics of the humbug damselfish, Dascyllus aruanus, through the measurement of gonadosomatic indices (GSI) and histological examination of the gonads. Fish were collected from Chuuk Lagoon, Micronesia (7°27'N; 151°53'E), between August 2009 and July 2010. Overall, the functional sex ratio was approximately 1:1; however, there was a female bias in the smaller size range (35-40 mm standard length [SL]) and male bias in the larger size range (45-60 mm in SL). The process of oocyte development exhibited a group synchronous pattern, from the vitellogenic phase oocytes in the gonads following the two clutches of oocytes, as the primary growth stage and yolk vesicle stage. The testis with an ovarian lumen exists as a central slit, and the sperm ducts extend into the medial hilar region of the gonads, indicating that males of D. aruanus have a secondary testis of protogynous species. Monthly variations in the GSI and evolution of gonad status indicated that reproductive activity in this species occurs throughout the year in Chuuk Lagoon, Micronesia.

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.

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

Structural and molecular brain sexual differences: A tool to understand sex differences in health and disease.

PubMed

Panzica, GianCarlo; Melcangi, Roberto C

2016-08-01

Sex differences are present both in the genotype and in the phenotype of all vertebrates, and they have been evidenced also within the central and peripheral nervous system. Earlier studies on brain sex differences suggested a relatively simple view based on (1) the presence of sexually dimorphic circuits in the hypothalamus (or in regions related to reproductive behaviors), (2) the action of gonadal hormones to masculinize the brain, and (3) the gonadal steroids' action to modulate gene transcription through nuclear receptors. These assumptions are today contradicted by the findings accumulated in the last 20 years. We know now that mechanisms determining sexual dimorphisms may vary according to location and species, and may involve several factors, as genes, epigenetic factors, gonadal hormones and neurosteroids. Sex differences were also revealed by epidemiological studies in several neural pathologies. This suggests that the approach to understand the genesis of these pathologies, should involve specific attention to interactions among genes, gonadal and brain-born steroid hormones, epigenetic and environmental factors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Raman spectroscopic analysis identifies testicular microlithiasis as intratubular hydroxyapatite.

PubMed

De Jong, B W D; De Gouveia Brazao, C A; Stoop, H; Wolffenbuttel, K P; Oosterhuis, J W; Puppels, G J; Weber, R F A; Looijenga, L H J; Kok, D J

2004-01-01

As diagnosed by ultrasonography, testicular microlithiasis is associated with various benign and malignant conditions. The molecular constitution of these microliths is largely unknown. Raman spectroscopy provides detailed in situ information about the molecular composition of tissues and to our knowledge it has not been applied to gonadal microliths. We analyzed the molecular composition of gonadal microlithiasis and its surrounding region using Raman spectroscopy in malignant and benign conditions. Multiple microliths from 6 independent samples diagnosed with gonadal microlithiasis by ultrasound and histologically confirmed were investigated by Raman spectroscopy. The samples included 4 testicular parenchyma samples adjacent to a germ cell tumor (4 seminomas), a gonadoblastoma of a dysgenetic gonad and testicular biopsy of a subfertile male without malignancy. Raman spectroscopic mapping demonstrated that testicular microliths were located within the seminiferous tubule. Glycogen surrounded all microliths in the samples associated with germ cell neoplasm but not in the benign case. The molecular composition of the 26 microliths in all 6 conditions was pure hydroxyapatite. Microliths in the testis are located in the seminiferous tubules and composed of hydroxyapatite. In cases of germ cell neoplasm they co-localize with glycogen deposits.

Control of lateral migration and germ cell elimination by the Drosophila melanogaster lipid phosphate phosphatases Wunen and Wunen 2

PubMed Central

Sano, Hiroko; Renault, Andrew D.; Lehmann, Ruth

2005-01-01

In most organisms, primordial germ cells (PGCs) arise far from the region where somatic gonadal precursors (SGPs) are specified. Although PGCs in general originate as a single cluster of cells, the somatic parts of the gonad form on each site of the embryo. Thus, to reach the gonad, PGCs not only migrate from their site of origin but also split into two groups. Taking advantage of high-resolution real-time imaging, we show that in Drosophila melanogaster PGCs are polarized and migrate directionally toward the SGPs, avoiding the midline. Unexpectedly, neither PGC attractants synthesized in the SGPs nor known midline repellents for axon guidance were required to sort PGCs bilaterally. Repellent activity provided by wunen (wun) and wunen-2 (wun-2) expressed in the central nervous system, however, is essential in this migration process and controls PGC survival. Our results suggest that expression of wun/wun-2 repellents along the migratory paths provides faithful control over the sorting of PGCs into two gonads and eliminates PGCs left in the middle of the embryo. PMID:16301333

The effect of the addition of cow brain powder in commercial feed on the gonadal maturity of comet goldfish (Carassius auratus auratus)

NASA Astrophysics Data System (ADS)

Andriani, Y.; Subhan, U.; Rosidah; Iskandar; Zidni, I.; Abdillah, A. M.

2018-04-01

The aim of this research was to analysis the effect of addition bovine’s brain meal in artificial feed on gonad maturity and to find out the best time of gonad maturity in comet fish.This research was conducted at Fourth Building Hatchery Faculty of Fisheries and Marine Sciences Padjadjaran University on November 2014 until Januari 2015. Freeze drying of bovine brain was conducted at Research Center Inter University Bandung Institute of Technology. The research was using Completely Randomized Design (CRD) with four treatments and three replications.The treatment were 20 mg/kg, 35 mg/kg, 50mg/kg and control. The parameters of this research are Gonado Somatic Index (GSI) and egg maturity level. Addition of bovine brain meal in feed with the dose of 50 mg/kg are giving the best result until 45 days of the care time against gonad maturity of comet fish with GSI result 12.93 %, egg maturity level ripe phase 21.115 and fecundity 1520 grain/g.

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. Copyright © 2013 Elsevier Inc. All rights reserved.

Roles of brca2 (fancd1) in oocyte nuclear architecture, gametogenesis, gonad tumors, and genome stability in zebrafish.

PubMed

Rodríguez-Marí, Adriana; Wilson, Catherine; Titus, Tom A; Cañestro, Cristian; BreMiller, Ruth A; Yan, Yi-Lin; Nanda, Indrajit; Johnston, Adam; Kanki, John P; Gray, Erin M; He, Xinjun; Spitsbergen, Jan; Schindler, Detlev; Postlethwait, John H

2011-03-01

Mild mutations in BRCA2 (FANCD1) cause Fanconi anemia (FA) when homozygous, while severe mutations cause common cancers including breast, ovarian, and prostate cancers when heterozygous. Here we report a zebrafish brca2 insertional mutant that shares phenotypes with human patients and identifies a novel brca2 function in oogenesis. Experiments showed that mutant embryos and mutant cells in culture experienced genome instability, as do cells in FA patients. In wild-type zebrafish, meiotic cells expressed brca2; and, unexpectedly, transcripts in oocytes localized asymmetrically to the animal pole. In juvenile brca2 mutants, oocytes failed to progress through meiosis, leading to female-to-male sex reversal. Adult mutants became sterile males due to the meiotic arrest of spermatocytes, which then died by apoptosis, followed by neoplastic proliferation of gonad somatic cells that was similar to neoplasia observed in ageing dead end (dnd)-knockdown males, which lack germ cells. The construction of animals doubly mutant for brca2 and the apoptotic gene tp53 (p53) rescued brca2-dependent sex reversal. Double mutants developed oocytes and became sterile females that produced only aberrant embryos and showed elevated risk for invasive ovarian tumors. Oocytes in double-mutant females showed normal localization of brca2 and pou5f1 transcripts to the animal pole and vasa transcripts to the vegetal pole, but had a polarized rather than symmetrical nucleus with the distribution of nucleoli and chromosomes to opposite nuclear poles; this result revealed a novel role for Brca2 in establishing or maintaining oocyte nuclear architecture. Mutating tp53 did not rescue the infertility phenotype in brca2 mutant males, suggesting that brca2 plays an essential role in zebrafish spermatogenesis. Overall, this work verified zebrafish as a model for the role of Brca2 in human disease and uncovered a novel function of Brca2 in vertebrate oocyte nuclear architecture.

Roles of brca2 (fancd1) in Oocyte Nuclear Architecture, Gametogenesis, Gonad Tumors, and Genome Stability in Zebrafish

PubMed Central

Rodríguez-Marí, Adriana; Wilson, Catherine; Titus, Tom A.; Cañestro, Cristian; BreMiller, Ruth A.; Yan, Yi-Lin; Nanda, Indrajit; Johnston, Adam; Kanki, John P.; Gray, Erin M.; He, Xinjun; Spitsbergen, Jan; Schindler, Detlev; Postlethwait, John H.

2011-01-01

Mild mutations in BRCA2 (FANCD1) cause Fanconi anemia (FA) when homozygous, while severe mutations cause common cancers including breast, ovarian, and prostate cancers when heterozygous. Here we report a zebrafish brca2 insertional mutant that shares phenotypes with human patients and identifies a novel brca2 function in oogenesis. Experiments showed that mutant embryos and mutant cells in culture experienced genome instability, as do cells in FA patients. In wild-type zebrafish, meiotic cells expressed brca2; and, unexpectedly, transcripts in oocytes localized asymmetrically to the animal pole. In juvenile brca2 mutants, oocytes failed to progress through meiosis, leading to female-to-male sex reversal. Adult mutants became sterile males due to the meiotic arrest of spermatocytes, which then died by apoptosis, followed by neoplastic proliferation of gonad somatic cells that was similar to neoplasia observed in ageing dead end (dnd)-knockdown males, which lack germ cells. The construction of animals doubly mutant for brca2 and the apoptotic gene tp53 (p53) rescued brca2-dependent sex reversal. Double mutants developed oocytes and became sterile females that produced only aberrant embryos and showed elevated risk for invasive ovarian tumors. Oocytes in double-mutant females showed normal localization of brca2 and pou5f1 transcripts to the animal pole and vasa transcripts to the vegetal pole, but had a polarized rather than symmetrical nucleus with the distribution of nucleoli and chromosomes to opposite nuclear poles; this result revealed a novel role for Brca2 in establishing or maintaining oocyte nuclear architecture. Mutating tp53 did not rescue the infertility phenotype in brca2 mutant males, suggesting that brca2 plays an essential role in zebrafish spermatogenesis. Overall, this work verified zebrafish as a model for the role of Brca2 in human disease and uncovered a novel function of Brca2 in vertebrate oocyte nuclear architecture. PMID:21483806

The hippocampal formation: morphological changes induced by thyroid, gonadal and adrenal hormones.

PubMed

Gould, E; Woolley, C S; McEwen, B S

1991-01-01

The hippocampal formation is of considerable interest due to its proposed role in a number of important functions, including learning and memory processes. Manipulations of thyroid, gonadal and adrenal hormones have been shown to influence hippocampal physiology as well as learning and memory. The cellular events which underlie these hormone-induced functional changes are largely unexplored. However, studies suggest that hormonal manipulations during development and in adulthood result in dramatic morphological changes within the hippocampal formation. Because neuronal physiology has been suggested to depend upon neuronal morphology, we have been determining the morphologic sensitivity of hippocampal neurons to thyroid and steroid hormones in an effort to elucidate possible structural mechanisms to account for differences in hippocampal function. In this review, hormone-induced structural changes in the developing and adult hippocampal formation are discussed, with particular emphasis on their functional relevance. Sex differences, as well as the developmental effects of thyroid hormone and glucocorticoids, are described. Moreover, the effects of ovarian steroids, thyroid hormone and glucocorticoids on neuronal morphology in the hippocampal formation of the adult rat are reviewed. These hormone-induced structural changes may account, at least in part, for previously reported hormone-induced changes in hippocampal function.

Methylation Patterns of SOX3, SOX9, and WNT4 Genes in Gonads of Dogs with XX (SRY-Negative) Disorder of Sexual Development.

PubMed

Salamon, Sylwia; Flisikowski, Krzysztof; Switonski, Marek

2017-01-01

Ovotesticular or testicular disorder of sexual development in dogs with female karyotype and lack of SRY (XX DSD) is a common sexual anomaly diagnosed in numerous breeds. The molecular background, however, remains unclear, and epigenetic mechanisms, including DNA methylation, have not been studied. The aim of our study was comparative methylation analysis of CpG islands in promoters of candidate genes for XX DSD: SOX9, SOX3, and WNT4. Methylation studies were performed on DNA extracted from formalin-fixed/paraffin-embedded or frozen gonads from 2 dogs with ovotesticular and 2 dogs with testicular XX DSD as well as control females (n = 4) and males (n = 2). Bisulfite-converted DNA was used for CpG methylation analysis using quantitative pyrosequencing. Promoter regions of SOX9 and WNT4 showed similar CpG methylation in each group, ranging from 0 to 5.5% and from 39 to 74%, respectively. The SOX3 promoter showed significantly higher methylation in the ovotesticular XX DSD cases and the testicular XX DSD and control males, suggesting that SOX3 methylation may play a role in canine XX DSD pathogenesis. © 2017 S. Karger AG, Basel.

De novo disruption of promoter and exon 1 of STAR gene reveals essential role for gonadal development.

PubMed

Piya, Anil; Kaur, Jasmeet; Rice, Alan M; Bose, Himangshu S

2017-01-01

Cholesterol transport into the mitochondria is required for synthesis of the first steroid, pregnenolone. Cholesterol is transported by the steroidogenic acute regulatory protein (STAR), which acts at the outer mitochondrial membrane prior to its import. Mutations in the STAR protein result in lipoid congenital adrenal hyperplasia (CAH). Although the STAR protein consists of seven exons, biochemical analysis in nonsteroidogenic COS-1 cells showed that the first two were not essential for pregnenolone synthesis. Here, we present a patient with ambiguous genitalia, salt-lossing crisis within two weeks after birth and low cortisol levels. Sequence analysis of the STAR , including the exon-intron boundaries, showed the complete deletion of exon 1 as well as more than 50 nucleotides upstream of STAR promoter. Mitochondrial protein import with the translated protein through synthesis cassette of the mutant STAR lacking exon 1 showed protein translation, but it is less likely to have synthesized without a promoter in our patient. Thus, a full-length STAR gene is necessary for physiological mitochondrial cholesterol transport in vivo . STAR exon 1 deletion caused lipoid CAH.Exon 1 substitution does not affect biochemical activity.StAR promoter is responsible for gonadal development.

Differences in peripheral sensory input to the olfactory bulb between male and female mice

NASA Astrophysics Data System (ADS)

Kass, Marley D.; Czarnecki, Lindsey A.; Moberly, Andrew H.; McGann, John P.

2017-04-01

Female mammals generally have a superior sense of smell than males, but the biological basis of this difference is unknown. Here, we demonstrate sexually dimorphic neural coding of odorants by olfactory sensory neurons (OSNs), primary sensory neurons that physically contact odor molecules in the nose and provide the initial sensory input to the brain’s olfactory bulb. We performed in vivo optical neurophysiology to visualize odorant-evoked OSN synaptic output into olfactory bub glomeruli in unmanipulated (gonad-intact) adult mice from both sexes, and found that in females odorant presentation evoked more rapid OSN signaling over a broader range of OSNs than in males. These spatiotemporal differences enhanced the contrast between the neural representations of chemically related odorants in females compared to males during stimulus presentation. Removing circulating sex hormones makes these signals slower and less discriminable in females, while in males they become faster and more discriminable, suggesting opposite roles for gonadal hormones in influencing male and female olfactory function. These results demonstrate that the famous sex difference in olfactory abilities likely originates in the primary sensory neurons, and suggest that hormonal modulation of the peripheral olfactory system could underlie differences in how males and females experience the olfactory world.

The role of kisspeptins and GPR54 in the neuroendocrine regulation of reproduction.

PubMed

Popa, Simina M; Clifton, Donald K; Steiner, Robert A

2008-01-01

Neurons that produce gonadotropin-releasing hormone (GnRH) reside in the basal forebrain and drive reproductive function in mammals. Understanding the circuitry that regulates GnRH neurons is fundamental to comprehending the neuroendocrine control of puberty and reproduction in the adult. This review focuses on a family of neuropeptides encoded by the Kiss1 gene, the kisspeptins, and their cognate receptor, GPR54, which have been implicated in the regulation of GnRH secretion. Kisspeptins are potent secretagogues for GnRH, and the Kiss1 gene is a target for regulation by gonadal steroids (e.g., estradiol and testosterone), metabolic factors (e.g., leptin), photoperiod, and season. Kiss1 neurons in the arcuate nucleus may regulate the negative feedback effect of gonadal steroids on GnRH and gonadotropin secretion in both sexes. The expression of Kiss1 in the anteroventral periventricular nucleus (AVPV) is sexually dimorphic, and Kiss1 neurons in the AVPV may participate in the generation of the preovulatory GnRH/luteinizing hormone (LH) surge in the female rodent. Kiss1 neurons have emerged as primary transducers of internal and environmental cues to regulate the neuroendocrine reproductive axis.

Wired on steroids: sexual differentiation of the brain and its role in the expression of sexual partner preferences.

PubMed

Alexander, Brenda M; Skinner, Donal C; Roselli, Charles E

2011-01-01

The preference to seek out a sexual partner of the opposite sex is robust and ensures reproduction and survival of the species. Development of female-directed partner preference in the male is dependent on exposure of the developing brain to gonadal steroids synthesized during critical periods of sexual differentiation of the central nervous system. In the absence of androgen exposure, a male-directed partner preference develops. The development and expression of sexual partner preference has been extensively studied in rat, ferret, and sheep model systems. From these models it is clear that gonadal testosterone, often through estrogenic metabolites, cause both masculinization and defeminization of behavior during critical periods of brain development. Changes in the steroid environment during these critical periods result in atypical sexual partner preference. In this manuscript, we review the major findings which support the hypothesis that the organizational actions of sex steroids are responsible for sexual differentiation of sexual partner preferences in select non-human species. We also explore how this information has helped to frame our understanding of the biological influences on human sexual orientation and gender identity.

Wired on Steroids: Sexual Differentiation of the Brain and Its Role in the Expression of Sexual Partner Preferences

PubMed Central

Alexander, Brenda M.; Skinner, Donal C.; Roselli, Charles E.

2011-01-01

The preference to seek out a sexual partner of the opposite sex is robust and ensures reproduction and survival of the species. Development of female-directed partner preference in the male is dependent on exposure of the developing brain to gonadal steroids synthesized during critical periods of sexual differentiation of the central nervous system. In the absence of androgen exposure, a male-directed partner preference develops. The development and expression of sexual partner preference has been extensively studied in rat, ferret, and sheep model systems. From these models it is clear that gonadal testosterone, often through estrogenic metabolites, cause both masculinization and defeminization of behavior during critical periods of brain development. Changes in the steroid environment during these critical periods result in atypical sexual partner preference. In this manuscript, we review the major findings which support the hypothesis that the organizational actions of sex steroids are responsible for sexual differentiation of sexual partner preferences in select non-human species. We also explore how this information has helped to frame our understanding of the biological influences on human sexual orientation and gender identity. PMID:22654808

Effects of chromosomal sex and hormonal influences on shaping sex differences in brain and behavior: Lessons from cases of disorders of sex development.

PubMed

Bramble, Matthew S; Lipson, Allen; Vashist, Neerja; Vilain, Eric

2017-01-02

Sex differences in brain development and postnatal behavior are determined largely by genetic sex and in utero gonadal hormone secretions. In humans however, determining the weight that each of these factors contributes remains a challenge because social influences should also be considered. Cases of disorders of sex development (DSD) provide unique insight into how mutations in genes responsible for gonadal formation can perturb the subsequent developmental hormonal milieu and elicit changes in normal human brain maturation. Specific forms of DSDs such as complete androgen insensitivity syndrome (CAIS), congenital adrenal hyperplasia (CAH), and 5α-reductase deficiency syndrome have variable effects between males and females, and the developmental outcomes of such conditions are largely dependent on sex chromosome composition. Medical and psychological works focused on CAH, CAIS, and 5α-reductase deficiency have helped form the foundation for understanding the roles of genetic and hormonal factors necessary for guiding human brain development. Here we highlight how the three aforementioned DSDs contribute to brain and behavioral phenotypes that can uniquely affect 46,XY and 46,XX individuals in dramatically different fashions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Framework for sex differences in adolescent neurobiology: A focus on cannabinoids

PubMed Central

Viveros, Maria-Paz; Marco-López, Eva María; López-Gallardo, Meritxell; Garcia-Segura, Luis Miguel; Wagner, Edward J.

2017-01-01

This review highlights the salient findings that have furthered our understanding of how sex differences are initiated during development and maintained throughout life. First we discuss how gonadal steroid hormones organize the framework for sex differences within critical periods of development—namely, during those exposures which occur in utero and post-partum, as well as those which occur during puberty. Given the extensive precedence of sex differences in cannabinoid-regulated biology, we then focus on the disparities within the endogenous cannabinoid system, as well as those observed with exogenously administered cannabinoids. We start with how the expression of cannabinoid CB1 receptors is regulated throughout development. This is followed by a discussion of differential vulnerability to the pathological sequelae stemming from cannabinoid exposure during adolescence. Next we talk about sex differences in the interactions between cannabinoids and other drugs of abuse, followed by the organizational and activational roles of gonadal steroids in establishing and maintaining the sex dependence in the biological actions of cannabinoids. Finally, we discuss ways to utilize this knowledge to strategically target critical developmental windows of vulnerability/susceptibility and thereby implement more effective therapeutic interventions for afflictions that may be more prevalent in one sex vs. the other. PMID:20869396

De novo disruption of promoter and exon 1 of STAR gene reveals essential role for gonadal development

PubMed Central

Piya, Anil; Kaur, Jasmeet; Rice, Alan M

2017-01-01

Summary Cholesterol transport into the mitochondria is required for synthesis of the first steroid, pregnenolone. Cholesterol is transported by the steroidogenic acute regulatory protein (STAR), which acts at the outer mitochondrial membrane prior to its import. Mutations in the STAR protein result in lipoid congenital adrenal hyperplasia (CAH). Although the STAR protein consists of seven exons, biochemical analysis in nonsteroidogenic COS-1 cells showed that the first two were not essential for pregnenolone synthesis. Here, we present a patient with ambiguous genitalia, salt-lossing crisis within two weeks after birth and low cortisol levels. Sequence analysis of the STAR, including the exon–intron boundaries, showed the complete deletion of exon 1 as well as more than 50 nucleotides upstream of STAR promoter. Mitochondrial protein import with the translated protein through synthesis cassette of the mutant STAR lacking exon 1 showed protein translation, but it is less likely to have synthesized without a promoter in our patient. Thus, a full-length STAR gene is necessary for physiological mitochondrial cholesterol transport in vivo. Learning points: STAR exon 1 deletion caused lipoid CAH. Exon 1 substitution does not affect biochemical activity. StAR promoter is responsible for gonadal development. PMID:28458886

The endoderm specifies the mesodermal niche for the germline in Drosophila via Delta-Notch signaling

PubMed Central

Okegbe, Tishina C.; DiNardo, Stephen

2011-01-01

Interactions between niche cells and stem cells are vital for proper control over stem cell self-renewal and differentiation. However, there are few tissues where the initial establishment of a niche has been studied. The Drosophila testis houses two stem cell populations, which each lie adjacent to somatic niche cells. Although these niche cells sustain spermatogenesis throughout life, it is not understood how their fate is established. Here, we show that Notch signaling is necessary to specify niche cell fate in the developing gonad. Surprisingly, our results indicate that adjacent endoderm is the source of the Notch-activating ligand Delta. We also find that niche cell specification occurs earlier than anticipated, well before the expression of extant markers for niche cell fate. This work further suggests that endoderm plays a dual role in germline development. The endoderm assists both in delivering germ cells to the somatic gonadal mesoderm, and in specifying the niche where these cells will subsequently develop as stem cells. Because in mammals primordial germ cells also track through endoderm on their way to the genital ridge, our work raises the possibility that conserved mechanisms are employed to regulate germline niche formation. PMID:21350008

Temporal Transcriptional Profiling of Somatic and Germ Cells Reveals Biased Lineage Priming of Sexual Fate in the Fetal Mouse Gonad

PubMed Central

Jameson, Samantha A.; Natarajan, Anirudh; Cool, Jonah; DeFalco, Tony; Maatouk, Danielle M.; Mork, Lindsey; Munger, Steven C.; Capel, Blanche

2012-01-01

The divergence of distinct cell populations from multipotent progenitors is poorly understood, particularly in vivo. The gonad is an ideal place to study this process, because it originates as a bipotential primordium where multiple distinct lineages acquire sex-specific fates as the organ differentiates as a testis or an ovary. To gain a more detailed understanding of the process of gonadal differentiation at the level of the individual cell populations, we conducted microarrays on sorted cells from XX and XY mouse gonads at three time points spanning the period when the gonadal cells transition from sexually undifferentiated progenitors to their respective sex-specific fates. We analyzed supporting cells, interstitial/stromal cells, germ cells, and endothelial cells. This work identified genes specifically depleted and enriched in each lineage as it underwent sex-specific differentiation. We determined that the sexually undifferentiated germ cell and supporting cell progenitors showed lineage priming. We found that germ cell progenitors were primed with a bias toward the male fate. In contrast, supporting cells were primed with a female bias, indicative of the robust repression program involved in the commitment to XY supporting cell fate. This study provides a molecular explanation reconciling the female default and balanced models of sex determination and represents a rich resource for the field. More importantly, it yields new insights into the mechanisms by which different cell types in a single organ adopt their respective fates. PMID:22438826

Rapid Change of Microbiota Diversity in the Gut but Not the Hepatopancreas During Gonadal Development of the New Shrimp Model Neocaridina denticulata.

PubMed

Cheung, Man Kit; Yip, Ho Yin; Nong, Wenyan; Law, Patrick Tik Wan; Chu, Ka Hou; Kwan, Hoi Shan; Hui, Jerome Ho Lam

2015-12-01

During evolution of animals, their co-evolution with bacteria has generally been ignored. Recent studies have provided evidences that the symbiotic bacteria in the animal gut can either be essential or contributing to the plasticity of the host. The Crustacea includes crab, crayfish, lobster, and shrimp and represents the second largest subphylum on the planet. Although there are already studies investigating the intestinal bacterial communities in crustaceans, none of them has examined the microbiota in different parts of the digestive system during the gonad development of the host. Here, we utilized a new shrimp model Neocaridina denticulata and sequenced the 16S rRNA using the Ion Torrent platform to survey the bacterial populations colonizing the hepatopancreas, foregut, and intestine, including midgut and hindgut, of the early, mid, and late ovarian maturation stages of the shrimp. The predominant bacteria phylum was found to be Proteobacteria, with more than 80 % reads from the gut flora at the early gonad development belonged to a Coxiella-type bacterium. Distinct bacterial communities can be detected between the hepatopancreas and gut, although no significant difference could be revealed between the different regions of the gut investigated. Surprisingly, during the gonad development, bacterial diversity changed rapidly in the gut but not the hepatopancreas. This study provides the first evidence that microbiota modified differentially in specific regions of the digestive tract during gonadal development of crustaceans.

The Mosaicism Ratio of 45,X May Explain the Phenotype in a Case of Mixed Gonadal Dysgenesis.

PubMed

Hatano, Megumi; Fukuzawa, Ryuji; Hasegawa, Yukihiro

2018-06-08

Some patients with mixed gonadal dysgenesis (MGD), whose prototypical karyotype is 45,X/46,XY, are known to manifest complications characteristic of Turner syndrome. We report a 16-year-old social male with MGD presenting with coarctation of the aorta, one of the common complications for Turner syndrome. At birth, the patient was found to have hypospadias, bifid scrotum, and cryptorchidism. Chromosomal analysis of his lymphocytes revealed the karyotype 45,X[7]/46,X,dic(Y;22)(p11.3;q13.3)[23] (named 45,X/46,X+Y fragment in this article). A left gonadectomy was performed at 1 year of age, and the histology showed a streak gonad with an epithelial cord-like structure compatible with MGD. At the age of 10 years, coarctation of the aorta was discovered by chance, for which the patient underwent surgical repair. The ratio of mosaicism in the gonad and aortic tissues was estimated by FISH with probes to identify the X centromere-specific repeat sequence and Yp11.2. The mosaicism ratio of 45,X/46,X+Y fragment varied among the tissues, with those having a higher ratio being more likely to exhibit the Turner syndrome phenotype. Some 90% of cells in the aortic tissues and 80% in the gonadal tissues lacked a Y chromosome. In conclusion, the mosaicism ratio in the different tissues may explain the phenotypes in MGD. © 2018 S. Karger AG, Basel.

Obesity independently influences gonadal function in very long-term adult male survivors of childhood cancer.

PubMed

Blijdorp, Karin; van Dorp, Wendy; Laven, Joop S E; Pieters, Rob; de Jong, Frank H; Pluijm, Saskia M F; van der Lely, Aart Jan; van den Heuvel-Eibrink, Marry M; Neggers, Sebastian J C M M

2014-08-01

Although obesity is associated with gonadal dysfunction in the general population, gonadotoxic treatment might diminish the impact of obesity in childhood cancer survivors (CCS). The aim was to evaluate whether altered body composition is associated with gonadal dysfunction in male CCS, independent of gonadotoxic cancer treatment. Three hundred fifty-one male CCS were included. Median age at diagnosis was 5.9 years (0-17.8) and median age at follow-up 25.6 years (18.0-45.8). Total and non-SHBG-bound testosterone, sex hormone-binding globulin, inhibin B, and follicle-stimulating hormone (FSH) were studied. Potential determinants were BMI, waist circumference, waist-hip ratio, and body composition measures (dual energy X-ray absorptiometry). Non-SHBG-bound testosterone was significantly decreased in survivors with BMI ≥ 30 kg/m(2) (adjusted mean 9.1 nmol/L vs. 10.2 nmol/L, P = 0.015), high fat percentage (10.0 vs. 11.2, P = 0.004), and high waist circumference (>102 cm) (9.0 vs. 11.0, P = 0.020). Survivors with high fat percentage (≥25%) had significantly lower inhibin B/FSH ratios (inhibin B/FSH ratio: β -34%, P = 0.041). Obesity is associated with gonadal dysfunction in male CCS, independent of the irreversible effect of previous cancer treatment. Randomized controlled trials are required to evaluate whether weight normalization could improve gonadal function, especially in obese survivors with potential other mechanisms than lifestyle causing their obesity. Copyright © 2014 The Obesity Society.

The use of anti-Müllerian hormone as diagnostic for gonadectomy status in dogs.

PubMed

Themmen, Axel P N; Kalra, Bhanu; Visser, Jenny A; Kumar, Ajay; Savjani, Gopal; de Gier, Jeffrey; Jaques, Scott

2016-10-01

In the veterinary practice, there is a need for a diagnostic tool to check the gonadal status in female dogs because it may be difficult to determine whether a female animal has been spayed or whether there are ovarian remnants. Although less prevalent, a similar situation pertains to male dogs. Anti-Müllerian hormone (AMH) is an important regulator of gonadal function and is a specific gonadal product that can be determined in circulation. The objective of this study was to develop and test a canine blood AMH assay as a diagnostic tool to determine the presence of functional gonadal tissue in dogs. A prospective study with a training-validation set paradigm was used. A canine AMH assay was developed and serum and plasma AMH concentrations were determined in blood samples from 46 intact female dogs, 48 spayed females, 50 intact males, and 48 castrated males collected at two separate institutes. Using a training-validation set paradigm, it was found that using cutoff values of 1.1 ng/mL (female) and 5.5 ng/mL (male) AMH, the assay reported excellent specificity and sensitivity of 100% and 90% in female dogs, and good specificity and sensitivity of 100% and 76%, in male dogs, respectively. The sensitivity in male dogs could be further enhanced by including a serum testosterone determination. This newly developed canine AMH assay is a valuable diagnostic tool to determine gonadal status in veterinary medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

Seasonal variation of biochemical components in clam ( Saxidomus purpuratus Sowerby 1852) in relation to its reproductive cycle and the environmental condition of Sanggou Bay, China

NASA Astrophysics Data System (ADS)

Bi, Jinhong; Li, Qi; Zhang, Xinjun; Zhang, Zhixin; Tian, Jinling; Xu, Yushan; Liu, Wenguang

2016-04-01

Seasonal variation of biochemical components in clam ( Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycle of clam. According to the histological analysis, the reproductive cycle of S. purpuratus includes two distinctive phases: a total spent and inactive stage from November to January, and a gametogenesis stage, including ripeness and spawning, during the rest of the year. Gametes were generated at a low temperature (2.1°C) in February. Spawning took place once a year from June to October. The massive spawning occurred in August when the highest water temperature and chlorophyll a level could be observed. The key biochemical components (glycogen, protein and lipid) in five tissues (gonad, foot, mantle, siphon and adductor muscle) were analyzed. The glycogen content was high before gametogenesis, and decreased significantly during the gonad development in the gonad, mantle and foot of both females and males, suggesting that glycogen was an important energy source for gonad development. The protein and lipid contents increased in the ovary during the gonad development, demonstrating that they are the major organic components of oocytes. The lipid and protein contents decreased in the testis, implying that they can provide energy and material for spermatogenesis. The results also showed that protein stored in the mantle and foot could support the reproduction after the glycogen was depleted.

Xenogenesis in teleost fish through generation of germ-line chimeras by single primordial germ cell transplantation.

PubMed

Saito, Taiju; Goto-Kazeto, Rie; Arai, Katsutoshi; Yamaha, Etsuro

2008-01-01

Primordial germ cells (PGCs) are the only cells in developing embryos with the potential to transmit genetic information to the next generation. PGCs therefore have the potential to be of value for gene banking and cryopreservation, particularly via the production of donor gametes with germ-line chimeras. Currently, it is not clear how many PGCs are required for germ-line differentiation and formation of gonadal structures. In the present study, we achieved complete germ-line replacement between two related teleost species, the pearl danio (Danio albolineatus) and the zebrafish (Danio rerio), with transplantation of a single PGC into each host embryo. We isolated and transplanted a single PGC into each blastula-stage, zebrafish embryo. Development of host germ-line cells was prevented by an antisense dead end morpholino oligonucleotide. In many host embryos, the transplanted donor PGC successfully migrated toward the gonadal anlage without undergoing cell division. At the gonadal anlage, the PGC differentiated to form one normally sized gonad rather than the pair of gonads usually present. Offspring were obtained from natural spawning of these chimeras. Analyses of morphology and DNA showed that the offspring were of donor origin. We extended our study to confirm that transplanted single PGCs of goldfish (Carassius auratus) and loach (Misgurnus anguillicaudatus) can similarly differentiate into sperm in zebrafish host embryos. Our results show that xenogenesis is realistic and practical across species, genus, and family barriers and can be achieved by the transplantation of a single PGC from a donor species.

Wide spectrum of NR5A1-related phenotypes in 46,XY and 46,XX individuals.

PubMed

Domenice, Sorahia; Machado, Aline Zamboni; Ferreira, Frederico Moraes; Ferraz-de-Souza, Bruno; Lerario, Antonio Marcondes; Lin, Lin; Nishi, Mirian Yumie; Gomes, Nathalia Lisboa; da Silva, Thatiana Evelin; Silva, Rosana Barbosa; Correa, Rafaela Vieira; Montenegro, Luciana Ribeiro; Narciso, Amanda; Costa, Elaine Maria Frade; Achermann, John C; Mendonca, Berenice Bilharinho

2016-12-01

Steroidogenic factor 1 (NR5A1, SF-1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1-related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype-phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian-determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1-related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever-expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal dysfunction. Birth Defects Research (Part C) 108:309-320, 2016. © 2016 The Authors Birth Defects Research Part C: Embryo Today: Reviews Published by Wiley Periodicals, Inc. © 2016 The Authors Birth Defects Research Part C: Embryo Today: Reviews Published by Wiley Periodicals, Inc.

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 females or a confounding effect of the higher nutrient loads in the Las Vegas Bay environment.

Effects of salinity on gonadal development, osmoregulation and metabolism of adult male Chinese mitten crab, Eriocheir sinensis

PubMed Central

Zhao, Lei; Ye, Haihui; Cheng, Yongxu; Zeng, Chaoshu

2017-01-01

As a catadromous species, salinity is a key parameter that affects gonadal development of Chinese mitten crab Eriocheir sinensis during reproductive migration. It is however unclear the effects of salinity on the gonadal development of male E. sinensis as well as their physiological responses to salinity during reproductive migration. This study investigated the effects of four salinities (0 ‰, 6 ‰, 12 ‰ and 18 ‰) on gonadal development, osmoregulation and metabolism of adult male E. sinensis over a 40-day period. The results showed that elevating salinity promote gonadal development, increase hemolymph osmolality and K+ and Mg2+ concentrations (P < 0.05). The 12 ‰ salinity resulted in the highest contents of taurine and arginine in the hemolymph while the highest contents of threonine, phenylalanine, lysine, ß-alanine, tryptophan, ornithine and total free amino acids were found for 0 ‰ treatment (P < 0.05). A decreasing trend was detected for the Na+/K+-ATPase activity and its mRNA expression level in the posterior gills with salinity (P < 0.05). Total saturated fatty acids in the anterior gills decreased with increasing salinity (P < 0.05); the 0 ‰ treatment had the highest total polyunsaturated fatty acids in the posterior gills while total n-6 polyunsaturated fatty acids increased with salinity (P < 0.05). The hemolymph glucose and uric acid showed a decreasing trend as salinity while an increasing trend was found for the hemolymph triglyceride and high-density lipoprotein cholesterol (P < 0.05). The 12 ‰ treatment had the highest levels of hemolymph malonaldehyde and hepatopancreatic γ-glutamyltranspeptidase (P < 0.05). In conclusion, these results suggested that the brackish water promote gonadal development of male E. sinensis, and increase osmolality and ionic concentrations in hemolymph while reduced the activity of Na+ /K+- ATPase and its mRNA expression in the posterior gills as well as metabolism. PMID:28628611

Gonadogenesis and annual reproductive cycles of an endangered cyprinid fish, the lake minnow Eupallasella percnurus (Pallas, 1814).

PubMed

Hliwa, Piotr; Król, Jarosław; Sikorska, Justyna; Wolnicki, Jacek; Dietrich, Grzegorz J; Kamiński, Rafał; Stabińska, Agnieszka; Ciereszko, Andrzej

2017-01-01

In this study, gonadogenesis, the effect of temperature (15, 20 and 25°C) on sex differentiation, and annual changes in the gonads of mature lake minnow Eupallasella percnurus (Pallas, 1814) were determined. The lake minnow was found to be a primary gonochoristic fish species, where gonads are formed directly in the ovaries or testes. The morphological differentiation of gonads was initiated 35days post hatch (DPH) when two types of gonadal anlages were visible: a pear-shaped gonad attached by a single mesentery string and a spindle-shaped gonad attached on both sides to the peritoneum. Gonadogenesis occurred faster in females than in males, with the first previtellogenic oocytes and ovarian lamellae being already observed in 45 DPH fish. In males, cytological differentiation occurred approximately 85 DPH, when the fish reached an average body weight of more than 400mg. No significant effect of rearing temperature on sex ratio in lake minnow juveniles was observed. The proportion of males and females was similar (close to 1:1) in all of the thermal-treated groups, although there were effects of temperature on the final sizes of fish. Histological examination of wild, mature lake minnow ovaries during the annual cycle (from May to February the following year) showed asynchronous oocyte maturation. The testes were characteristic of multi-batch spawning fish. Quantitative dominance of spermatids and mature spermatozoa in May was observed, while the presence of primary and secondary spermatocytes in all other periods was confirmed. These changes were also reflected in the seasonal variation in the gonado-somatic index in both sexes, with the highest mean values of 11.2% (females) and 4.0% (males) in May, which were found to be significantly different to all other periods. The data presented in this study provide an important contribution to our understanding of the biology and reproductive strategy of the endangered lake minnow. Copyright © 2016 Elsevier B.V. All rights reserved.

Aromatase, steroid-5-alpha-reductase type 1 and type 2 mRNA expression in gonads and in brain of Xenopus laevis during ontogeny.

PubMed

Urbatzka, R; Lutz, I; Kloas, W

2007-01-01

The key enzymes involved in the production of endogenous sex steroids are steroid-5-alpha-reductase and aromatase converting testosterone (T) into dihydrotestosterone (DHT) and into estradiol (E2), respectively. To gain more insights into the molecular mechanisms of sexual differentiation of amphibians, we determined the mRNA expression of steroid-5-alpha-reductase type1 (Srd5a1), type2 (Srd5a2) and aromatase (Aro) during ontogeny starting from the egg and ending after completion of metamorphosis in Xenopus laevis. Expression of all three enzymes was measured by means of semi-quantitative RT-PCR, determining for the first time Srd5a1 and Srd5a2 mRNA expression in amphibians. mRNA was analyzed in whole body homogenates from stage 12 to 48, while brain and gonads with kidney were studied separately from stage 48 to 66. Different ontogenetic mRNA expression patterns were observed for all genes analyzed, revealing early mRNA expression of Srd5a1 already in the egg at stage 12 whereas Srd5a2 and Aro was detected at stage 39. Sex-specific mRNA expressions of Srd5a2 and of Aro were determined in the gonads with kidney but not in brain. Srd5a2 was two-fold higher expressed in testes than in ovaries while Aro mRNA was ten-fold higher in ovaries. No gender-specific mRNA expression was observed for Srd5a1 in gonads and in brain. The ontogenetic patterns of Aro, Srd5a1 and Srd5a2 suggest that these genes are involved in sexual differentiation of gonads and brain already in early developmental stages. Especially in gonads Srd5a2 seems to be important for physiological regulation of testis development while Aro is associated with the development of ovaries.

The mRNA expression of P450 aromatase, gonadotropin beta-subunits and FTZ-F1 in the orange-spotted grouper (Epinephelus Coioides) during 17alpha-methyltestosterone-induced precocious sex change.

PubMed

Zhang, Weimin; Zhang, Yong; Zhang, Lihong; Zhao, Huihong; Li, Xin; Huang, He; Lin, Haoran

2007-06-01

The orange-spotted grouper Epinephelus coioides is a protogynous hermaphroditic fish, but the physiological basis of its sex change remains largely unknown. In the present study, the 2-year-old orange-spotted grouper was induced to change sex precociously by oral administration of 17alpha-methyltestosterone (MT, 50 mg/Kg diet, twice a day at daily ration of 5% bodyweight) for 60 days. The serum testosterone levels were significantly elevated after MT treatment for 20 and 40 days as compared to control, but the levels of serum estradiol (E(2)) remained unchanged. The expression of P450aromA in the gonad significantly decreased after MT treatment for 20, 40, and 60 days. Accordingly, the enzyme activity of gonadal aromatase was also lower. The expression of FSHbeta subunit in the pituitary was significantly decreased after MT treatment for 20 days, but returned to the control levels after 40 and 60 days; however, the expression of LHbeta subunit was not altered significantly by MT treatment. The expression of FTZ-F1 in the gonad also decreased significantly in response to MT treatment for 40 and 60 days, but its expression in the pituitary was not altered significantly. Interestingly, when tested in vitro on ovarian fragments, MT had no direct effect on the expression of P450aromA and FTZ-F1 as well as the activity of gonadal aromatase, suggesting that the inhibition of gonadal P450aromatase and FTZ-F1 by MT may be mediated at upper levels of the brain-pituitary-gonadal axis. Taken together, these results indicated that FSH, P450aromA, FTZ-F1, and serum testosterone are associated with the MT-induced sex change of the orange-spotted grouper, but the cause-effect relationship between these factors and sex change in this species remains to be characterized. (c) 2006 Wiley-Liss, Inc.

Control of molt in birds: association with prolactin and gonadal regression in starlings.

PubMed

Dawson, Alistair

2006-07-01

Despite the importance of molt to birds, very little is known about its environmental or physiological control. In starlings Sturnus vulgaris, and other species, under both natural conditions and experimental regimes, gonadal regression coincides with peak prolactin secretion. The prebasic molt starts at the same time. The aim of this series of experiments was to keep starlings on photo-schedules that would challenge the normally close relationship between gonadal regression and molt, to determine how closely the start of molt is associated with gonadal regression and/or associated changes in prolactin concentrations. In one series of experiments, photosensitive starlings were moved from a short photoperiod, 8 h light per day (8L), to 13 or 18L, and from 13 to 18L or 13 to 8L during testicular maturation. Later, photorefractory birds under 13L that had finished molting were moved to 18L. In another series of experiments, photorefractory starlings were moved from 18 to 8L for 7 weeks, 4 weeks, 2 weeks, 1 week, 3 days, 1 day, or 0 days, before being returned to 18L. There was no consistent relationship between photoperiod, or the increase in photoperiod, and the timing of the start of molt. Nor was there a consistent relationship with gonadal regression and the start of molt-molt could be triggered in the absence of a gonadal cycle. However, there was always an association between the start of molt and prolactin. In all cases where molt was induced, there had been an earlier increase in prolactin. However, the timing of molt was related to the time of peak prolactin, not the magnitude of that peak. This relationship between peak prolactin and the start of molt could explain the normally close relationship between the end of breeding activity and the start of molt.

Primary sex determination of placental mammals: a modelling study uncovers dynamical developmental constraints in the formation of Sertoli and granulosa cells.

PubMed

Sánchez, Lucas; Chaouiya, Claudine

2016-05-26

Primary sex determination in placental mammals is a very well studied developmental process. Here, we aim to investigate the currently established scenario and to assess its adequacy to fully recover the observed phenotypes, in the wild type and perturbed situations. Computational modelling allows clarifying network dynamics, elucidating crucial temporal constrains as well as interplay between core regulatory modules. Relying on a comprehensive revision of the literature, we define a logical model that integrates the current knowledge of the regulatory network controlling this developmental process. Our analysis indicates the necessity for some genes to operate at distinct functional thresholds and for specific developmental conditions to ensure the reproducibility of the sexual pathways followed by bi-potential gonads developing into either testes or ovaries. Our model thus allows studying the dynamics of wild type and mutant XX and XY gonads. Furthermore, the model analysis reveals that the gonad sexual fate results from the operation of two sub-networks associated respectively with an initiation and a maintenance phases. At the core of the process is the resolution of two connected feedback loops: the mutual inhibition of Sox9 and ß-catenin at the initiation phase, which in turn affects the mutual inhibition between Dmrt1 and Foxl2, at the maintenance phase. Three developmental signals related to the temporal activity of those sub-networks are required: a signal that determines Sry activation, marking the beginning of the initiation phase, and two further signals that define the transition from the initiation to the maintenance phases, by inhibiting the Wnt4 signalling pathway on the one hand, and by activating Foxl2 on the other hand. Our model reproduces a wide range of experimental data reported for the development of wild type and mutant gonads. It also provides a formal support to crucial aspects of the gonad sexual development and predicts gonadal phenotypes for mutations not tested yet.

Genome-wide analysis of brain and gonad transcripts reveals changes of key sex reversal-related genes expression and signaling pathways in three stages of Monopterus albus.

PubMed

Chi, Wei; Gao, Yu; Hu, Qing; Guo, Wei; Li, Dapeng

2017-01-01

The natural sex reversal severely affects the sex ratio and thus decreases the productivity of the rice field eel (Monopterus albus). How to understand and manipulate this process is one of the major issues for the rice field eel stocking. So far the genomics and transcriptomics data available for this species are still scarce. Here we provide a comprehensive study of transcriptomes of brain and gonad tissue in three sex stages (female, intersex and male) from the rice field eel to investigate changes in transcriptional level during the sex reversal process. Approximately 195 thousand unigenes were generated and over 44.4 thousand were functionally annotated. Comparative study between stages provided multiple differentially expressed genes in brain and gonad tissue. Overall 4668 genes were found to be of unequal abundance between gonad tissues, far more than that of the brain tissues (59 genes). These genes were enriched in several different signaling pathways. A number of 231 genes were found with different levels in gonad in each stage, with several reproduction-related genes included. A total of 19 candidate genes that could be most related to sex reversal were screened out, part of these genes' expression patterns were validated by RT-qPCR. The expression of spef2, maats1, spag6 and dmc1 were abundant in testis, but was barely detected in females, while the 17β-hsd12, zpsbp3, gal3 and foxn5 were only expressed in ovary. This study investigated the complexity of brain and gonad transcriptomes in three sex stages of the rice field eel. Integrated analysis of different gene expression and changes in signaling pathways, such as PI3K-Akt pathway, provided crucial data for further study of sex transformation mechanisms.

Disorders of sexual development and associated changes in the pituitary-gonadal axis in dogs.

PubMed

Buijtels, J J C W M; de Gier, J; Kooistra, H S; Grinwis, G C M; Naan, E C; Zijlstra, C; Okkens, A C

2012-10-15

Normal sexual differentiation depends on completion of chromosomal sex determination, gonadal differentiation, and development of the phenotypic sex. An irregularity in any of these three steps can lead to a disorder in sexual development (DSD). We examined nine dogs with DSD by abdominal ultrasonography, laparotomy, histologic examination of the gonads, and reproductive tract, cytogenetic analysis, and mRNA expression of the SRY gene. We also determined the plasma concentrations of luteinizing hormone (LH), estradiol-17β, and testosterone before and after administration of gonadotropin-releasing hormone (GnRH) and compared these results with those obtained in anestrous bitches and male control dogs. The gonads of three dogs with DSD contained both testicular and ovarian tissue, while in the other six only testicular tissue was found. Each of the dogs had a uterus. Based on gynecologic examination, cytogenetic analysis, and the histology of the gonads, seven of the nine dogs appeared to be XX sex reversals. Three of these were XX true hermaphrodites and four were XX males; the other two dogs had incomplete XY gonadal dysgenesis. All seven XX sex-reversed dogs were found to be negative for the SRY gene by polymerase chain reaction. The basal plasma luteinizing hormone (LH) concentration was significantly higher in dogs with DSD than in anestrous bitches but not significantly different from that in male dogs. The basal plasma LH concentration increased significantly after GnRH administration in all dogs with DSD. The basal plasma estradiol concentration was significantly higher in dogs with DSD than in anestrous bitches but not significantly different from that in male dogs. The basal plasma testosterone concentration was lower in dogs with DSD than in male dogs. In all dogs with DSD both the basal and GnRH-induced plasma testosterone concentrations were above the upper limit of their respective ranges in the anestrous bitches. In conclusion, the secretion of LH and estradiol in these dogs with DSD, all of which had testicular tissue in their gonads, was similar to that in male control dogs. These results indicate that the basal and/or GnRH-stimulated plasma testosterone concentration might be used to detect the presence of testicular tissue in dogs with DSD. Copyright © 2012 Elsevier Inc. All rights reserved.

Interaction of gonadal steroids and the glucocorticoid corticosterone in the regulation of the L-type Ca(2+) current in rat left ventricular cardiomyocytes.

PubMed

Wagner, M; Moritz, A; Volk, T

2011-08-01

Gonadal steroids as well as glucocorticoids have been shown to regulate the cardiac L-type Ca(2+) current (I(CaL) ). Herein, we compare the effects of the gonadal steroids testosterone and 17β-estradiol with the glucocorticoid corticosterone on I(CaL) , and investigate the interaction between the gonadal steroids and corticosterone. Myocytes were isolated from the left ventricular free wall of female and male Wistar rats and investigated using the ruptured-patch whole-cell patch-clamp technique. In myocytes isolated from female rats, 24 h incubation with 100 nm testosterone led to a 33% increase in I(CaL) compared with control (-8.8 ± 0.5 pA pF(-1) , n = 25 vs. -6.6 ± 0.4 pA pF(-1) , n = 26, P < 0.01, V(Pip) = 0 mV). Incubation with 1 μm corticosterone resulted in a 79% increase in I(CaL) (-11.8 ± 0.7 pA pF(-1) , n = 29, P < 0.001). However, the combination of testosterone and corticosterone did not have any additional effect compared with corticosterone alone (-11.7 ± 0.6 pA pF(-1) , n = 25, ns). In cardiomyocytes from male rats, I(CaL) was not affected by testosterone, whereas the effect of corticosterone was preserved (P < 0.05). 24 h incubation with 17β-estradiol increased I(CaL) by 32% from -7.6 ± 0.5 pA pF(-1) (n = 15) to 10.0 ± 0.9 pA pF(-1) (n = 15, P < 0.05). 17β-estradiol did not exert an additional effect upon co-incubation with corticosterone and did not have an effect on I(CaL) in cardiomyocytes from female rats. Higher concentrations of the gonadal steroids did not result in increased effects. When compared with corticosterone, the in vitro effects of the gonadal steroids are small. However, under conditions in which I(CaL) is not fully activated by glucocorticoids, gonadal steroids may significantly contribute to I(CaL) regulation. © 2011 The Authors. Acta Physiologica © 2011 Scandinavian Physiological Society.

Mechanisms associated with an advance in the timing of seasonal reproduction in an urban songbird

USGS Publications Warehouse

Fudickar, Adam M.; Greives, Timothy J; Abolins-Abols, Mikas; Atwell, Jonathan W.; Meddle, Simone L.; Friis, Guillermo; Stricker, Craig A.; Ketterson, Ellen D.

2017-01-01

The colonization of urban environments by animals is often accompanied by earlier breeding and associated changes in seasonal schedules. Accelerated timing of seasonal reproduction in derived urban populations is a potential cause of evolutionary divergence from ancestral populations if differences in physiological processes that regulate reproductive timing become fixed over time. We compared reproductive development in free-living and captive male dark-eyed juncos deriving from a population that recently colonized a city (~35 years) and ceased migrating to that of conspecifics that live in sympatry with the urban population during winter and spring but migrate elsewhere to breed. We predicted that the earlier breeding sedentary urban birds would exhibit accelerated reproductive development in the spring along the hypothalamic-pituitary-gonadal (HPG) axis as compared to migrants. We found that free-living sedentary urban and migrant juncos differed at the level of the pituitary when measured as baseline luteinizing hormone (LH) levels, but not in increased LH when challenged with Gonadotropin-Releasing Hormone (GnRH). Among captives held in a common garden, and at the level of the gonad, we found that sedentary urban birds produced more testosterone in response to GnRH than migrants living in the same common environment, suggesting greater gonadal sensitivity in the derived urban population. Greater gonadal sensitivity could arise from greater upstream activation by LH or FSH or from reduced suppression of gonadal development by the adrenal axis. We compared abundance of gonadal transcripts for LH receptor (LHR), follicle stimulating hormone receptor (FSHR), glucocorticoid receptor (GR), and mineralocorticoid receptor (MR) in the common-garden, predicting either more abundant transcripts for LHR and FSHR or fewer transcripts for GR and MR in the earlier breeding sedentary urban breeders, as compared to the migrants. We found no difference in the expression of these genes. Together these data suggest that advanced timing of reproduction in a recently derived urban population is facilitated by earlier increase in upstream baseline activity of the HPG and earlier release from gonadal suppression by yet-to-be-discovered mechanisms. Evolutionarily, our results suggest that potential for gene flow between seasonally sympatric populations may be limited due to urban-induced advances in the timing of reproduction and resulting allochrony with ancestral forms.

A study of temporal effects of the model anti-androgen flutamide on components of the hypothalamic-pituitary-gonadal axis in adult fathead minnows

EPA Science Inventory

The aim of this study was to investigate temporal changes in the hypothalamic-pituitary-gonadal (HPG) axis of fathead minnow (Pimephales promelas) treated with the model androgen receptor (AR) antagonist, flutamide. Reproductively-mature fish were exposed in a flow-through, meas...

GONADAL DEVELOPMENT AND ENDOCRINE RESPONSES IN JAPANESE MEDAKA (ORYZIAS LATIPES) EXPOSED TO O,P'-DDT IN WATER OR THROUGH MATERNAL TRANSFER

EPA Science Inventory

Various isomers and metabolites of DDT disrupt endocrine systems and gonadal development in fish andxwildlife and o,p'-DDT has been shown to be a relatively potent estrogen agonist. In this study, we exposed Japanese medaka (Oryzias latipes) to o,p'-DDT using two exposure protoco...

Pain and sex hormones: a review of current understanding.

PubMed

Maurer, Adrian J; Lissounov, Alexei; Knezevic, Ivana; Candido, Kenneth D; Knezevic, Nebojsa Nick

2016-01-01

Multiple epidemiologic studies have demonstrated an increased prevalence for women in several chronic pain disorders. Clinical and experimental investigations have consistently demonstrated sex-specific differences in pain sensitivity and pain threshold. Even though the underlying mechanisms responsible for these differences have not yet been elucidated, the logical possibility of gonadal hormone influence on nociceptive processing has garnered recent attention. In this review, we evaluated the complex literature regarding gonadal hormones and their influence on pain perception. We reviewed the numerous functions of gonadal hormones, discussed the influence of these hormones on several common chronic pain syndromes (migraine, tension and cluster headaches, fibromyalgia, temporomandibular syndrome, rheumatoid arthritis and back pain, among others), and have attempted to draw conclusions from the available data.

The Number of X Chromosomes Causes Sex Differences in Adiposity in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Chen, Jenny; Beaven, Simon W.; Tontonoz, Peter

2012-01-01

Sexual dimorphism in body weight, fat distribution, and metabolic disease has been attributed largely to differential effects of male and female gonadal hormones. Here, we report that the number of X chromosomes within cells also contributes to these sex differences. We employed a unique mouse model, known as the “four core genotypes,” to distinguish between effects of gonadal sex (testes or ovaries) and sex chromosomes (XX or XY). With this model, we produced gonadal male and female mice carrying XX or XY sex chromosome complements. Mice were gonadectomized to remove the acute effects of gonadal hormones and to uncover effects of sex chromosome complement on obesity. Mice with XX sex chromosomes (relative to XY), regardless of their type of gonad, had up to 2-fold increased adiposity and greater food intake during daylight hours, when mice are normally inactive. Mice with two X chromosomes also had accelerated weight gain on a high fat diet and developed fatty liver and elevated lipid and insulin levels. Further genetic studies with mice carrying XO and XXY chromosome complements revealed that the differences between XX and XY mice are attributable to dosage of the X chromosome, rather than effects of the Y chromosome. A subset of genes that escape X chromosome inactivation exhibited higher expression levels in adipose tissue and liver of XX compared to XY mice, and may contribute to the sex differences in obesity. Overall, our study is the first to identify sex chromosome complement, a factor distinguishing all male and female cells, as a cause of sex differences in obesity and metabolism. PMID:22589744

Reproductive and bloom patterns of Pelagia noctiluca in the Strait of Messina, Italy

NASA Astrophysics Data System (ADS)

Milisenda, G.; Martinez-Quintana, A.; Fuentes, V. L.; Bosch-Belmar, M.; Aglieri, G.; Boero, F.; Piraino, S.

2018-02-01

Investigations on sexual reproduction of jellyfish are essential to understanding mechanisms and patterns of outbreaks formation. Pelagia noctiluca (Forskål, 1775) (Scyphozoa) is known as the predominant jellyfish species with direct development in Western and Central Mediterranean Sea. In this paper we used integrated morphometric, histological, and biochemical approaches to investigate the annual reproductive biology of P. noctiluca from the Strait of Messina (South Thyrrenian Sea), a key proliferation area for this species due to favourable temperatures and high productivity. From November 2011 to September 2012, P. noctiluca sexual reproduction occurred throughout the year, with two seasonal peaks (autumn, spring) of spawning and embryonic development. Gonads of female P. noctiluca were characterized by a large amount of mature eggs of small size (diameter < 200 μm) during high food availability, whereas fewer, larger eggs (diameter > 200 μm) were detected during low availability of prey. Two morphometric indexes were applied: the Gonad-Somatic Index (GSI, gonadal/somatic tissue dry weight ratio) and Fecundity Index (FI, n° eggs mm-2 * gonadal dry weight). The FI showed longer spawning periods than the GSI, providing a better causal-mechanistic explanation for the year-round occurrence of P. noctiluca in the Strait of Messina. Protein contents of the gonads changed seasonally, with the highest concentrations during the pre-spawning periods. We suggest that investigations on jellyfish sexual reproduction can provide biological information relevant for understanding mechanisms of jellyfish blooms as well as for the management of coastal zones affected by outbreaks of gelatinous species.

Brain nonapeptide and gonadal steroid responses to deprivation of heterosexual contact in the black molly

PubMed Central

Kulczykowska, Ewa; Kalamarz-Kubiak, Hanna; Nietrzeba, Marta; Gozdowska, Magdalena

2015-01-01

ABSTRACT Fish may respond to different social situations with changes in both physiology and behaviour. A unique feature of fish is that social interactions between males and females strongly affect the sexual characteristics of individuals. Here we provide the first insight into the endocrine background of two phenomena that occur in mono-sex groups of the black molly (Poecilia sphenops): masculinization in females and same-sex sexual behaviour, manifested by gonopodial displays towards same-sex tank mates and copulation attempts in males. In socially controlled situations, brain neurohormones impact phenotypic sex determination and sexual behaviour. Among these hormones are the nonapeptides arginine vasotocin (AVT) and isotocin (IT), counterparts of the well-known mammalian arginine vasopressin and oxytocin, respectively. To reveal potential hormone interactions, we measured the concentrations of bioactive AVT and IT in the brain, along with those of the sex steroids 17β-estradiol and 11-ketotestosterone in the gonads, of females, masculinized females, males displaying same-sex sexual behaviour and those who did not. These data were supplemented by morphological and histological analyses of the gonads. Correlations between brain nonapeptides and gonadal steroids strongly suggest a cross talk between hormonal systems. In the black molly, the masculinization process was associated with the production of brain AVT and gonadal steroids, whereas same-sex sexual behaviour involves both brain nonapeptides, but neither of the sex steroids. This study extends current knowledge of endocrine control of phenotypic sex and sexual behaviour in fish and for the first time links brain nonapeptides with the occurrence of male-male sexual behaviour in lower vertebrates. PMID:25527645

The molecular and cellular basis of gonadal sex reversal in mice and humans

PubMed Central

Warr, Nick; Greenfield, Andy

2012-01-01

The mammalian gonad is adapted for the production of germ cells and is an endocrine gland that controls sexual maturation and fertility. Gonadal sex reversal, namely, the development of ovaries in an XY individual or testes in an XX, has fascinated biologists for decades. The phenomenon suggests the existence of genetic suppressors of the male and female developmental pathways and molecular genetic studies, particularly in the mouse, have revealed controlled antagonism at the core of mammalian sex determination. Both testis and ovary determination represent design solutions to a number of problems: how to generate cells with the right properties to populate the organ primordium; how to produce distinct organs from an initially bipotential primordium; how to pattern an organ when the expression of key cell fate determinants is initiated only in a discrete region of the primordium and extends to other regions asynchronously; how to coordinate the interaction between distinct cell types in time and space and stabilize the resulting morphology; and how to maintain the differentiated state of the organ throughout the adult period. Some of these, and related problems, are common to organogenesis in general; some are distinctive to gonad development. In this review, we discuss recent studies of the molecular and cellular events underlying testis and ovary development, with an emphasis on the phenomenon of gonadal sex reversal and its causes in mice and humans. Finally, we discuss sex-determining loci and disorders of sex development in humans and the future of research in this important area. WIREs Dev Biol 2012, 1:559–577. doi: 10.1002/wdev.42 PMID:23801533

5S rRNA and accompanying proteins in gonads: powerful markers to identify sex and reproductive endocrine disruption in fish.

PubMed

Diaz de Cerio, Oihane; Rojo-Bartolomé, Iratxe; Bizarro, Cristina; Ortiz-Zarragoitia, Maren; Cancio, Ibon

2012-07-17

In anuran ovaries, 5S rDNA is regulated transcriptionally by transcription factor IIIA (TFIIIA), which upon transcription, binds 5S rRNA, forming 7S RNP. 5S rRNA can be stockpiled also in the form of 42S RNP bound to 42sp43. The aim of the present study was to assess the differential transcriptional regulation of 5S rRNA and associated proteins in thicklip gray mullet (Chelon labrosus) gonads. Up to 75% of the total RNA from mullet ovaries was 5S rRNA. qPCR quantification of 5S rRNA expression, in gonads of histologically sexed individuals from different geographical areas, successfully sexed animals. All males had expression levels that were orders of magnitude below expression levels in females, throughout an annual reproductive cycle, with the exception of two individuals: one in November and one in December. Moreover, intersex mullets from a polluted harbor had expression levels between both sexes. TFIIIA and 42sp43 were also very active transcriptionally in gonads of female and intersex mullets, in comparison to males. Nucleocytoplasmatic transport is important in this context and we also analyzed transcriptional levels of importins-α1, -α2, and -β2 and different exportins. Importin-αs behaved similarly to 5S rRNA. Thus, 5S rRNA and associated proteins constitute very powerful molecular markers of sex and effects of xenosterogens in fish gonads, with potential technological applications in the analysis of fish stock dynamics and reproduction as well as in environmental health assessment.

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.

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

Lipid content in hepatic and gonadal adipose tissue parallel aortic cholesterol accumulation in mice fed diets with different omega-6 PUFA to EPA plus DHA ratios

USDA-ARS?s Scientific Manuscript database

Diets with low omega (u)-6 polyunsaturated fatty acids (PUFA) to eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) ratios have been shown to decrease aortic cholesterol accumulation and have been suggested to promote weight loss. The involvement of the liver and gonadal adipose tissue (GAT...

Zinc and copper bioaccumulation in fish from Laizhou Bay, the Bohai Sea

NASA Astrophysics Data System (ADS)

Liu, Jinhu; Cao, Liang; Huang, Wei; Zhang, Chuantao; Dou, Shuozeng

2014-05-01

Zinc (Zn) and copper (Cu) concentrations were determined in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five commercial fish species (mullet Liza haematocheilus, flathead Platycephalus indicus, mackerel Scomberomorus niphonius, silver pomfret Pampus argenteus, and sea bass Lateolabrax japonicus) from Laizhou Bay in the Bohai Sea. Metal bioaccumulation was highest in the metabolically active tissues of the gonads and liver. Bioconcentration factors for Zn were higher in all tissues (gonads 44.35, stomach 7.73, gills 7.72, liver 5.61, skin 4.88, and muscle 1.63) than the corresponding values for Cu (gonads 3.50, stomach 3.00, gills 1.60, liver 5.43, skin 1.50, and muscle 0.93). Mackerel tissues accumulated metal to higher concentrations than did other fish species, but bioaccumulation levels were not significantly correlated with the trophic levels of the fish. Zn and Cu concentrations in the tissues were generally negatively correlated with fish length, except for a few tissues of sea bass. Risk assessment based on national and international permissible limits and provisional tolerances for weekly intake of Zn and Cu revealed that the concentrations of these two metals in muscle were relatively low and would not pose hazards to human health.