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1.
Chemosphere ; 286(Pt 1): 131639, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346330

RESUMO

Metals are one of the contaminants released from the increase of anthropic activities. They can be classified as endocrine disruptors once they can affect the reproductive parameters of different organisms. The aim of the study was to evaluate the potential effects of cadmium on regulatory reproduction axis (Hypothalamic-Pituitary-Gonadal-Liver, the HPGL axis) in females of Rhamdia quelen exposed to nominal concentrations of 0.1; 1; 10 and 100 µg.L-1 of cadmium. After 15 days, tissues were collected for hormonal quantification, brain aromatase (cyp19a1b), hepatic vitellogenin (vtg) gene expression, and biomarkers analysis. Cadmium was quantified in water, gonad and liver samples. The plasma levels of estradiol, testosterone and gonad and hepatosomatic indexes did not changed after Cd exposure. The cyp19a1b was not different among the groups. Cadmium was detected at higher concentrations in the liver compared to the gonads. No genotoxicity was observed, only erythrocytes nuclear alterations. Metallothionein was reduced at 10 µg.L-1 in the liver and 10 and 100 µg.L-1 in the gonad. Hepatic superoxide dismutase activity increased and this can lead to a hydrogen peroxide increase, one of reactive oxygen species. This increase without a compensation of other enzymes of the antioxidant system can lead to lipoperoxidation, as occurred at 100 µg.L-1. Hepatic vitellogenin gene expression increased as well as the injury index at 0,1 and 100 µg.L-1. The tested cadmium concentrations have been found in the freshwater ecosystems and can affect the female reproductive regulation axis HPGL of the Neotropical species R. quelen.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Animais , Cádmio/toxicidade , Ecossistema , Disruptores Endócrinos/toxicidade , Feminino , Gônadas , Fígado , Reprodução , Vitelogeninas/genética , Poluentes Químicos da Água/toxicidade
2.
Food Chem ; 371: 131114, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34638013

RESUMO

This study aimed to examine the gelation and microstructural properties of scallop male gonad hydrolysates (SMGHs) in the presence of low-acyl gellan gum (GG) at different mass ratios. The rheological results showed that both elastic modulus and thermal stability of SMGHs were significantly improved by the addition of GG. Meanwhile, the relaxation time T23 was significantly reduced in SMGHs/GG by low-field nuclear magnetic resonance, indicating a strong interaction between SMGHs and GG. Fourier transform infrared spectroscopy indicated the blueshift of amide I and II peaks in SMGHs/GG further demonstrated the electrostatic interaction between SMGHs and GG. The network structure of SMGHs/GG binary complexes was more compact and the surface was smoother than that of SMGHs by cryo-scanning electron microscopy. Furthermore, increasing the content of GG in the SMGHs/GG binary complex significantly reinforced the gel strength and promoted the gelation process.


Assuntos
Pectinidae , Hidrolisados de Proteína , Animais , Gônadas , Masculino , Polissacarídeos Bacterianos
3.
Artigo em Inglês | MEDLINE | ID: mdl-34639376

RESUMO

Aging is associated with gender-specific hormonal changes that progressively lead to gonadal insufficiency, a condition which characterizes a minority of men and all women. Work-related factors, such as stress and pollutant exposure, affect gonadal function and can interfere with reproduction in both genders. A systematic review of the PubMed, SCOPUS and EMBASE databases was conducted, according to the Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) statement to investigate the effect of occupational factors on andropause and menopause. A total of 26 studies met the inclusion and exclusion criteria: 9 studies evaluated the effects of work on andropause symptoms, 8 studies examined its effects on age at menopause onset, and 9 studies addressed its effects on menopausal symptoms. Work-related factors, such as psychological stress, physical effort, and sleep disorders, showed a significant correlation with andropause manifestations, whereas age at menopause and severity of menopausal symptoms were both influenced by factors such as pesticide exposure, high job strain, and repetitive work. Since work accompanies men and women for most of their lives, it is essential to identify and prevent the risk factors that may affect reproductive health.


Assuntos
Andropausa , Envelhecimento , Feminino , Gônadas , Humanos , Masculino , Menopausa , Reprodução
4.
Hum Genet ; 140(12): 1733-1751, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34647195

RESUMO

Mitochondrial disorders are collectively common, genetically heterogeneous disorders in both pediatric and adult populations. They are caused by molecular defects in oxidative phosphorylation, failure of essential bioenergetic supply to mitochondria, and apoptosis. Here, we present three affected individuals from a consanguineous family of Pakistani origin with variable seizures and intellectual disability. Both females display primary ovarian insufficiency (POI), while the male shows abnormal sex hormone levels. We performed whole exome sequencing and identified a recessive missense variant c.694C > T, p.Arg232Cys in TFAM that segregates with disease. TFAM (mitochondrial transcription factor A) is a component of the mitochondrial replisome machinery that maintains mtDNA transcription and replication. In primary dermal fibroblasts, we show depletion of mtDNA and significantly altered mitochondrial function and morphology. Moreover, we observed reduced nucleoid numbers with significant changes in nucleoid size or shape in fibroblasts from an affected individual compared to controls. We also investigated the effect of tfam impairment in zebrafish; homozygous tfam mutants carrying an in-frame c.141_149 deletion recapitulate the mtDNA depletion and ovarian dysgenesis phenotypes observed in affected humans. Together, our genetic and functional data confirm that TFAM plays a pivotal role in gonad development and expands the repertoire of mitochondrial disease phenotypes.


Assuntos
DNA Mitocondrial , Proteínas de Ligação a DNA/genética , Genes Recessivos , Perda Auditiva/genética , Deficiência Intelectual/genética , Proteínas Mitocondriais/genética , Insuficiência Ovariana Primária/genética , Convulsões/genética , Fatores de Transcrição/genética , Animais , Células Cultivadas , Feminino , Gônadas/embriologia , Humanos , Masculino , Linhagem , Peixe-Zebra/genética
5.
Theriogenology ; 176: 188-193, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34624813

RESUMO

The dead end gene has been identified as a essential factor for Primordial germ cells (PGCs) migration and survival in many species, but its role in Monopterus albus is unclear. In order to clarify the function of dead end gene in M.albus PGCs migration and survival, we first characterized the expression profile of M.albus dead end (Madnd) in developing embryos and various tissues. qRT-PCR revealed that Madnd transcripts were exclusively detected in gonad, including ovary, testis and ovotestis.Embryos injected with a Madnd morpholino (Madnd-MO) exhibited down-regulation of the vasa gene. Furthermore, the GFP signal show the PGCs migration in control group were injected with GFP-nanos3 3'-UTR mRNA for visualization, as described in a previous study, yet it was disappeared after embryos injected with Madnd-MO.Finally, we characterized the genomics sequence of the Madnd gene and designed five gRNAs for genome editing. Three gRNAs were selected for microinjection according to the results of in vitro tests. gRNAd1 was used for microinjection with the Cas9 protein and was confirmed to be effective. Our analysis in this study suggested that Madnd play a key role in PGCs migration and survival in M. albus. These data provide the basis for the production of fast-growing and reproductively M.albus sterile.


Assuntos
Células Germinativas , Smegmamorpha , Animais , Sobrevivência Celular , Enguias , Feminino , Gônadas , Masculino
6.
Eur J Endocrinol ; 185(5): 717-728, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34519276

RESUMO

Objective: Female patients treated with alkylating agents in childhood are at risk for ovarian impairment. We aimed at describing the pattern of residual ovarian function in a cohort of survivors of hematological malignancies and/or hematopoietic stem cell transplantation (HSCT) and assessing the relationship between cyclophosphamide equivalent dose (CED) and anti-Müllerian hormone (AMH). Design and methods: Gonadal health was clinically and biochemically assessed in 124 post-menarchal survivors who underwent treatment for pediatric hematological malignancies and/or HSCT between 1992 and 2019. Results: Overt 'premature ovarian insufficiency' (POI) was detected in 72.1 and 3.7% of transplanted and non-transplanted patients, respectively; milder 'diminished ovarian reserve' (DOR) in 16.3 and 22.2%. In non-transplanted patients, increasing CED values were associated with lower AMH-SDS (P = 0.04), with the threshold of 7200 g/m2 being the best discriminator between DOR/POI and normal ovarian function (AUC: 0.75 on ROC analysis) and with an observed decrease of 0.14 AMH-SDS for each CED increase of 1 g/m2. In addition, age at diagnosis ≥10 years played a detrimental role on ovarian reserve (P = 0.003). In the HSCT group, irradiation was associated with a statistically significant reduction in AMH-SDS (P = 0.04). Conclusions: In non-transplanted patients, CED ≥ 7200 mg/m2 was associated with a DOR, while younger age at diagnosis played a protective role on ovarian reserve. As a result of the data collected, we propose a systematic algorithm to assess iatrogenic gonadal impairment in young female patients exposed to chemo-radiotherapy in childhood for hematological disorders.


Assuntos
Hormônio Antimülleriano/sangue , Gônadas/fisiologia , Transplante de Células-Tronco Hematopoéticas , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/fisiopatologia , Reserva Ovariana , Adolescente , Adulto , Fatores Etários , Algoritmos , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/uso terapêutico , Biomarcadores/sangue , Criança , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Feminino , Nível de Saúde , Humanos , Neoplasias Ovarianas/radioterapia , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/fisiopatologia , Radioterapia/efeitos adversos , Estudos Retrospectivos , Adulto Jovem
7.
Braz J Biol ; 83: e249158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550290

RESUMO

The knowledge of the testicular and ovarian morphology of a particular fish species is of paramount importance. Such analyze enables the development of studies and techniques aiming the improvement of their reproduction, management, commercialization and even their conservation. This study performed the ovarian and testicular characterization of the ornamental Amazon fish Serrapinnus kriegi. A total of three males and three females had their gonads analyzed by optical microscopy. Females present ovaries filled with oocytes in asynchronous development, indicating partial spawning in the species. Moreover, the micropyle and micropilar cell formation was observed in primary growing oocytes, representing a precocious oocyte development; and the zona radiata in the final vitellogenic oocytes is thicker than other related species, evidencing the development of a better protection to the embryos in function of the waters' turbulence that characterize it spawning sites in the Amazonian streams. The male specimens' present anastomosed tubular testes with unrestricted spermatogonia spread along the entire seminiferous tubules. The present data elucidate the dynamic of spermatogenesis and oogenesis of an ornamental Amazonian species, through the description of the male and female germ cells development.


Assuntos
Characidae , Animais , Feminino , Gônadas , Masculino , Oócitos , Oogênese , Ovário , Testículo
8.
Int J Mol Sci ; 22(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34576257

RESUMO

Although anti-Müllerian hormone (AMH) has classically been correlated with the regression of Müllerian ducts in male mammals, involvement of this growth factor in other reproductive processes only recently come to light. Teleost is the only gnathostomes that lack Müllerian ducts despite having amh orthologous genes. In adult teleost gonads, Amh exerts a role in the early stages of germ cell development in both males and females. Mechanisms involving the interaction of Amh with gonadotropin- and growth factor-induced functions have been proposed, but our overall knowledge regarding Amh function in fish gonads remains modest. In this study, we report on Amh actions in the European sea bass ovary. Amh and type 2 Amh receptor (Amhr2) are present in granulosa and theca cells of both early and late-vitellogenic follicles and cannot be detected in previtellogenic ovaries. Using the Pichia pastoris system a recombinant sea bass Amh has been produced that is endogenously processed to generate a 12-15 kDa bioactive mature protein. Contrary to previous evidence in lower vertebrates, in explants of previtellogenic sea bass ovaries, mature Amh has a synergistic effect on steroidogenesis induced by the follicle-stimulating hormone (Fsh), increasing E2 and cyp19a1a levels.


Assuntos
Hormônio Antimülleriano/química , Hormônio Foliculoestimulante/metabolismo , Ovário/metabolismo , Receptores de Peptídeos/química , Receptores de Fatores de Crescimento Transformadores beta/química , Proteínas Recombinantes/química , Animais , Hormônio Antimülleriano/metabolismo , Bass , Células COS , Chlorocebus aethiops , Estradiol/metabolismo , Feminino , Gonadotropinas/metabolismo , Gônadas/metabolismo , Células da Granulosa/metabolismo , Imunoensaio , Folículo Ovariano/metabolismo , Plasmídeos/metabolismo , Esteroides/metabolismo , Células Tecais/metabolismo , Vitelogênese
9.
Pediatr Ann ; 50(9): e359-e365, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34542337

RESUMO

Throughout the history of Western culture, sex has been reflected as a binary rule, with this binary system affecting self-expression, lifestyle choices, and health outcomes of everyone, but especially those with intersex traits. "Intersex" (or differences of sex development) is an umbrella term used to describe a wide range of natural variations in genitalia, gonads, and chromosome patterns that do not fit typical binary notions of male or female bodies. Currently, people who identify as intersex or as having intersex traits are not provided with the appropriate care needed for their wellbeing. Intersex health care has undergone a great deal of change in the last century, led by intersex leaders and advocates. Clinician advocates have also played a vital role. This article will focus on this history of intersex health care evolution, the role of clinician advocacy, and suggestions for how clinicians can become advocates for improving intersex health care. [Pediatr Ann. 2021;50(9):e359-e365.].


Assuntos
Atenção à Saúde/tendências , Transtornos do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/terapia , Feminino , Gônadas/anatomia & histologia , Humanos , Masculino , Defesa do Paciente , Papel do Médico
10.
Elife ; 102021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477553

RESUMO

Understanding the molecular events that regulate cell pluripotency versus acquisition of differentiated somatic cell fate is fundamentally important. Studies in Caenorhabditis elegans demonstrate that knockout of the germline-specific translation repressor gld-1 causes germ cells within tumorous gonads to form germline-derived teratoma. Previously we demonstrated that endoplasmic reticulum (ER) stress enhances this phenotype to suppress germline tumor progression(Levi-Ferber et al., 2015). Here, we identify a neuronal circuit that non-autonomously suppresses germline differentiation and show that it communicates with the gonad via the neurotransmitter serotonin to limit somatic differentiation of the tumorous germline. ER stress controls this circuit through regulated inositol requiring enzyme-1 (IRE-1)-dependent mRNA decay of transcripts encoding the neuropeptide FLP-6. Depletion of FLP-6 disrupts the circuit's integrity and hence its ability to prevent somatic-fate acquisition by germline tumor cells. Our findings reveal mechanistically how ER stress enhances ectopic germline differentiation and demonstrate that regulated Ire1-dependent decay can affect animal physiology by controlling a specific neuronal circuit.


Assuntos
Caenorhabditis elegans/fisiologia , Diferenciação Celular/fisiologia , Células Germinativas/fisiologia , Neurônios/fisiologia , Animais , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caspases , Estresse do Retículo Endoplasmático/fisiologia , Gônadas , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade de RNA
11.
Theriogenology ; 173: 56-63, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333168

RESUMO

Pacific bluefin tuna (PBT), Thunnus orientalis, is one of the most important species for aquaculture in Japan. Recently, the reduction in muscle fat content associated with sexual maturation in farmed PBT has become a serious problem. To develop technologies for inducing sterility, detailed and reliable data on gonadal development in PBT are needed. Here, we demonstrated the process of gonadal sex differentiation, and of early ovarian and testicular development during the immature stages in PBT. Gonadal sex differentiation was first characterized by the formation of the ovarian cavity in female and of the efferent ducts in male 57 days post hatching (dph). The gonads then differentiated into ovaries or testes according to the genotypic sex until 83 dph. During this period, primordial germ cells, oogonia, and type-A spermatogonia were solitarily distributed in the gonads, and the number of germ cells did not differ between sexes. After gonadal sex differentiation, gonads of PBTs developed in a sexually dimorphic manner: proliferation and differentiation of germ cells occurred earlier in the ovaries than in the testes. The oogonia in ovaries formed cysts at 185 dph, but the type-A spermatogonia were solitarily distributed in testes at this stage, and cysts of type-A spermatogonia were first observed at 247 dph. Moreover, the oogonia entered meiosis and differentiated into chromatin-nucleolus stage oocytes until 247 dph, and subsequently into peri-nucleolus stage oocytes until 285 dph, whereas the type-A spermatogonia differentiated into type-B spermatogonia, spermatocytes, spermatids, and spermatozoa from 446 dph onwards. We believe the results of this study provide the necessary basis for future studies on sterile PBT production.


Assuntos
Diferenciação Sexual , Testículo , Animais , Feminino , Gônadas , Masculino , Ovário , Espermatogônias , Atum
12.
J Exp Biol ; 224(7)2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424970

RESUMO

Thymus plasticity following gonadectomy or sex hormone replacement has long since exemplified sex hormone effects on the immune system in mammals and, to a lesser extent, in 'lower vertebrates', including amphibians and fish. Nevertheless, the underlying physiological significances as well as the ontogenetic establishment of this crosstalk remain largely unknown. Here, we used a teleost fish, the European sea bass, Dicentrarchus labrax, to investigate: (1) whether the regulation of thymus plasticity relies on resource trade-off with somatic growth and reproductive investment and (2) if the gonad-thymus interaction takes place during gonadal differentiation and development. Because gonadal development and, supposedly, thymus function in sea bass depend on environmental changes associated with the winter season, we evaluated thymus changes (foxn1 expression, and thymocyte and T cell content) in juvenile D. labrax raised for 1 year under either constant or fluctuating photoperiod and temperature. Importantly, in both conditions, intensive gonadal development following sex differentiation coincided with a halt of thymus growth, while somatic growth continued. To the best of our knowledge, this is the first study showing that gonadal development during prepuberty regulates thymus plasticity. This finding may provide an explanation for the initiation of the thymus involution related to ageing in mammals. Comparing fixed and variable environmental conditions, our work also demonstrates that the extent of the effects on the thymus, which are related to reproduction, depend on ecophysiological conditions, rather than being directly related to sexual maturity and sex hormone levels.


Assuntos
Bass , Gônadas , Animais , Fotoperíodo , Reprodução , Diferenciação Sexual
13.
BMC Genomics ; 22(1): 609, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372770

RESUMO

BACKGROUND: In the animal kingdom, mollusca is an important phylum of the Lophotrochozoa. However, few studies have investigated the molecular cascade of sex determination/early gonadal differentiation within this phylum. The oyster Crassostrea gigas is a sequential irregular hermaphrodite mollusc of economic, physiological and phylogenetic importance. Although some studies identified genes of its sex-determining/-differentiating pathway, this particular topic remains to be further deepened, in particular with regard to the expression patterns. Indeed, these patterns need to cover the entire period of sex lability and have to be associated to future sex phenotypes, usually impossible to establish in this sequential hermaphrodite. This is why we performed a gonadal RNA-Seq analysis of diploid male and female oysters that have not changed sex for 4 years, sampled during the entire time-window of sex determination/early sex differentiation (stages 0 and 3 of the gametogenetic cycle). This individual long-term monitoring gave us the opportunity to explain the molecular expression patterns in the light of the most statistically likely future sex of each oyster. RESULTS: The differential gene expression analysis of gonadal transcriptomes revealed that 9723 genes were differentially expressed between gametogenetic stages, and 141 between sexes (98 and 43 genes highly expressed in females and males, respectively). Eighty-four genes were both stage- and sex-specific, 57 of them being highly expressed at the time of sex determination/early sex differentiation. These 4 novel genes including Trophoblast glycoprotein-like, Protein PML-like, Protein singed-like and PREDICTED: paramyosin, while being supported by RT-qPCR, displayed sexually dimorphic gene expression patterns. CONCLUSIONS: This gonadal transcriptome analysis, the first one associated with sex phenotypes in C. gigas, revealed 57 genes highly expressed in stage 0 or 3 of gametogenesis and which could be linked to the future sex of the individuals. While further study will be needed to suggest a role for these factors, some could certainly be original potential actors involved in sex determination/early sex differentiation, like paramyosin and could be used to predict the future sex of oysters.


Assuntos
Crassostrea , Animais , Crassostrea/genética , Feminino , Perfilação da Expressão Gênica , Gônadas , Humanos , Masculino , Fenótipo , Filogenia , Diferenciação Sexual/genética , Transcriptoma
14.
FASEB J ; 35(9): e21876, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34449112

RESUMO

Compared with the well-described XY sex determination system in mammals, the avian ZW sex determination system is poorly understood. Knockdown and overexpression studies identified doublesex and mab-3-related transcription factor 1 (DMRT1) as the testis-determining gene in chicken. However, the detailed effects of DMRT1 gene disruption from embryonic to adult development are not clear. Herein, we have generated DMRT1-disrupted chickens using the clustered regularly interspaced short palindromic repeats-associated protein 9 system, followed by an analysis of physiological, hormonal, and molecular changes in the genome-modified chickens. In the early stages of male chicken development, disruption of DMRT1 induced gonad feminization with extensive physiological and molecular changes; however, functional feminine reproductivity could not be implemented with disturbed hormone synthesis. Subsequent RNA-sequencing analysis of the DMRT1-disrupted chicken gonads revealed gene networks, including several novel genes linearly and non-linearly associated with DMRT1, which are involved in gonad feminization. By comparing the gonads of wild type with the genome-modified chickens, a set of genes were identified that is involved in the ZW sex determination system independent of DMRT1. Our results extend beyond the Z-dosage hypothesis to provide further information about the avian ZW sex determination system and epigenetic effects of gonad feminization.


Assuntos
Galinhas/genética , Feminização/genética , Gônadas/fisiologia , Fatores de Transcrição/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Masculino , Ovário/fisiologia , Cromossomos Sexuais , Testículo/fisiologia
15.
Development ; 148(16)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34387307

RESUMO

During early embryogenesis in amniotic vertebrates, the gonads differentiate into either ovaries or testes. The first cell lineage to differentiate gives rise to the supporting cells: Sertoli cells in males and pre-granulosa cells in females. These key cell types direct the differentiation of the other cell types in the gonad, including steroidogenic cells. The gonadal surface epithelium and the interstitial cell populations are less well studied, and little is known about their sexual differentiation programs. Here, we show the requirement of the homeobox transcription factor gene TGIF1 for ovarian development in the chicken embryo. TGIF1 is expressed in the two principal ovarian somatic cell populations: the cortex and the pre-granulosa cells of the medulla. TGIF1 expression is associated with an ovarian phenotype in estrogen-mediated sex reversal experiments. Targeted misexpression and gene knockdown indicate that TGIF1 is required, but not sufficient, for proper ovarian cortex formation. In addition, TGIF1 is identified as the first known regulator of juxtacortical medulla development. These findings provide new insights into chicken ovarian differentiation and development, specifically cortical and juxtacortical medulla formation.


Assuntos
Galinhas/genética , Genes Homeobox , Proteínas de Homeodomínio/genética , Ovário/embriologia , Proteínas Repressoras/genética , Animais , Diferenciação Celular , Linhagem da Célula/genética , Embrião de Galinha , Embrião de Mamíferos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Gônadas/metabolismo , Proteínas de Homeodomínio/metabolismo , Masculino , Ovário/citologia , Ovário/metabolismo , Proteínas Repressoras/metabolismo , Células de Sertoli/metabolismo , Processos de Determinação Sexual/genética , Diferenciação Sexual/genética , Testículo/metabolismo
16.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360982

RESUMO

Reproductive function depends upon an operational hypothalamo-pituitary-gonadal (HPG) axis. Due to its role in determining survival versus reproductive strategies, the HPG axis is vulnerable to a diverse plethora of signals that ultimately manifest with Central Hypogonadism (CH) in all its many guises. Acquired CH can result from any pituitary or hypothalamic lesion, including its treatment (such as surgical resection and/or radiotherapy). The HPG axis is particularly sensitive to the suppressive effects of hyperprolactinaemia that can occur for many reasons, including prolactinomas, and as a side effect of certain drug therapies. Physiologically, prolactin (combined with the suppressive effects of autonomic neural signals from suckling) plays a key role in suppressing the gonadal axis and establishing temporary CH during lactation. Leptin is a further key endocrine regulator of the HPG axis. During starvation, hypoleptinaemia (from diminished fat stores) results in activation of hypothalamic agouti-related peptide neurons that have a dual purpose to enhance appetite (important for survival) and concomitantly suppresses GnRH neurons via effects on neural kisspeptin release. Obesity is associated with hyperleptinaemia and leptin resistance that may also suppress the HPG axis. The suppressibility of the HPG axis also leaves it vulnerable to the effects of external signals that include morphine, anabolic-androgenic steroids, physical trauma and stress, all of which are relatively common causes of CH. Finally, the HPG axis is susceptible to congenital malformations, with reports of mutations within >50 genes that manifest with congenital CH, including Kallmann Syndrome associated with hyposmia or anosmia (reduction or loss of the sense of smell due to the closely associated migration of GnRH with olfactory neurons during embryogenesis). Analogous to the HPG axis itself, patients with CH are often vulnerable, and their clinical management requires both sensitivity and empathy.


Assuntos
Síndrome de Kallmann/metabolismo , Animais , Gônadas/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Síndrome de Kallmann/tratamento farmacológico , Síndrome de Kallmann/genética , Leptina/metabolismo , Prolactina/metabolismo
17.
Sci Rep ; 11(1): 16819, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413402

RESUMO

We here analysed the populations' genetic structure of Coscinasterias tenuispina, an Atlantic-Mediterranean fissiparous starfish, focusing on the western Mediterranean, to investigate: the distribution and prevalence of genetic variants, the relative importance of asexual reproduction, connectivity across the Atlantic-Mediterranean transition, and the potential recent colonisation of the Mediterranean Sea. Individuals from 11 Atlantic-Mediterranean populations of a previous study added to 172 new samples from five new W Mediterranean sites. Individuals were genotyped at 12 microsatellite loci and their gonads histologically analysed for sex determination. Additionally, four populations were genotyped at two-time points. Results demonstrated genetic homogeneity and low clonal richness within the W Mediterranean, due to the dominance of a superclone, but large genetic divergence with adjacent areas. The lack of new genotypes recruitment over time, and the absence of females, confirmed that W Mediterranean populations were exclusively maintained by fission and reinforced the idea of its recent colonization. The existence of different environmental conditions among basins and/or density-depend processes could explain this lack of recruitment from distant areas. The positive correlation between clonal richness and heterozygote excess suggests that most genetic diversity is retained within individuals in the form of heterozygosity in clonal populations, which might increase their resilience.


Assuntos
Estrelas-do-Mar/genética , Animais , Teorema de Bayes , Células Clonais , Análise por Conglomerados , Feminino , Variação Genética , Geografia , Gônadas/fisiologia , Heterozigoto , Larva/genética , Masculino , Região do Mediterrâneo , Processos de Determinação Sexual , Fatores de Tempo
18.
Mar Biotechnol (NY) ; 23(5): 683-694, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34365528

RESUMO

The dopaminergic signaling pathway is involved in many physiological functions in vertebrates, but poorly documented in protostome species except arthropods. We functionally characterized a novel dopamine receptor in the Pacific oyster (Crassostrea gigas), activated by dopamine and tyramine with different efficacy and potency orders. This receptor - Cragi-DOP2R - belongs to the D1-like family of receptors and corresponds to the first representative of the Dop2/invertebrate-type dopamine receptor (Dop2/INDR) group ever identified in Lophotrochozoa. Cragi-DOP2R transcripts were expressed in various adult tissues, with higher expression levels in the visceral ganglia and the gills. Following an experiment under acute osmotic conditions, Cragi-DOP2R transcripts significantly increased in the visceral ganglia and decreased in the gills, suggesting a role of dopamine signaling in the mediation of osmotic stress. Furthermore, a role of the Cragi-DOP2R signaling pathway in female gametogenesis and in early oyster development was strongly suggested by the significantly higher levels of receptor transcripts in mature female gonads and in the early embryonic stages.


Assuntos
Crassostrea/metabolismo , Receptores Dopaminérgicos/metabolismo , Transdução de Sinais , Animais , Crassostrea/genética , Crassostrea/crescimento & desenvolvimento , Dopamina/genética , Dopamina/metabolismo , Feminino , Regulação da Expressão Gênica , Gônadas/metabolismo , Receptores Dopaminérgicos/genética , Salinidade
19.
Nature ; 597(7876): 410-414, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34408322

RESUMO

Signals from sympathetic neurons and immune cells regulate adipocytes and thereby contribute to fat tissue biology. Interactions between the nervous and immune systems have recently emerged as important regulators of host defence and inflammation1-4. Nevertheless, it is unclear whether neuronal and immune cells co-operate in brain-body axes to orchestrate metabolism and obesity. Here we describe a neuro-mesenchymal unit that controls group 2 innate lymphoid cells (ILC2s), adipose tissue physiology, metabolism and obesity via a brain-adipose circuit. We found that sympathetic nerve terminals act on neighbouring adipose mesenchymal cells via the ß2-adrenergic receptor to control the expression of glial-derived neurotrophic factor (GDNF) and the activity of ILC2s in gonadal fat. Accordingly, ILC2-autonomous manipulation of the GDNF receptor machinery led to alterations in ILC2 function, energy expenditure, insulin resistance and propensity to obesity. Retrograde tracing and chemical, surgical and chemogenetic manipulations identified a sympathetic aorticorenal circuit that modulates ILC2s in gonadal fat and connects to higher-order brain areas, including the paraventricular nucleus of the hypothalamus. Our results identify a neuro-mesenchymal unit that translates cues from long-range neuronal circuitry into adipose-resident ILC2 function, thereby shaping host metabolism and obesity.


Assuntos
Tecido Adiposo/inervação , Tecido Adiposo/metabolismo , Encéfalo/metabolismo , Imunidade Inata/imunologia , Mesoderma/citologia , Vias Neurais , Neurônios/citologia , Obesidade/metabolismo , Tecido Adiposo/citologia , Animais , Encéfalo/citologia , Sinais (Psicologia) , Citocinas/metabolismo , Metabolismo Energético , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Gônadas/metabolismo , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Sistema Nervoso Simpático/citologia , Sistema Nervoso Simpático/metabolismo
20.
J Fish Biol ; 99(5): 1719-1728, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34392530

RESUMO

Individuals of the same species may present different reproductive tactics depending on the environment in which they develop and mature. The present study aimed to define the gonadal development phases of males and females of Astyanax rivularis and to carry out a comparative analysis of the reproductive development of specimens captured in two isolated environments of the São Francisco River basin in Serra da Canastra, Brazil (Point 1: low vegetation and river showing calm and crystalline waters with small well formations; Point 2: current waters, and well-established areas of arboreal vegetation). Thus, the gonads of A. rivularis specimens were collected, fixed and processed with techniques for light microscopy. Five maturation phases of the females' reproductive cycle were established: immature, developing, spawning capable, regressing and regenerating. Three maturation phases of the males' reproductive cycle were observed: spawning capable, regressing, and regenerating. There are differences in the phases of gonadal development of A. rivularis between the two sampling points so that, possibly, animals upstream of the waterfall demonstrate a delay in the reproductive cycle in relation to animals downstream.


Assuntos
Characidae , Animais , Brasil , Feminino , Gônadas , Masculino , Reprodução , Rios
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