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1.
Mar Environ Res ; 160: 104985, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907723

RESUMO

This study aims at (1) experimentally estimating first sexual maturation of the European sardine S. pilchardus, (2) using the results to calibrate existing bioenergetic models. During the 183 days-experiment, fish growth and body condition were assessed by biometry, and gonads were weighed when present. Age, wet weight and total length at first maturity were estimated at 262 days, 10.79 ± 0.75 g, and 11.26 ± 0.21 cm, respectively. Including these traits in biphasic Von Bertalanffy models did not significantly improve simulations for either length or weight data, meaning that energy allocation was not impacted by these traits. The implementation of the results in the Dynamic Energy Budget (DEB) calibration procedure strengthened the parameter set of the existing model, but resulted in significant changes in the energy allocation. Our results are a first step that will allow the design of new experiments to further quantify maturation and reproduction rates in diverse environmental conditions, consolidating DEB model calibration.


Assuntos
Peixes , Alimentos Marinhos , Animais , Metabolismo Energético , Peixes/crescimento & desenvolvimento , Gônadas
2.
Medicine (Baltimore) ; 99(34): e21831, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846829

RESUMO

Adoption of interventional endoscopic procedures is increasing with increasing prevalence of diseases. However, medical radiation exposure is concerning; therefore, radiation protection for medical staff is important. However, there is limited information on the usefulness of an additional lead shielding device during interventional endoscopic procedures. Therefore, we aimed to determine whether an additional lead shielding device protects medical staff from radiation.An X-ray unit (CUREVISTA; Hitachi Medical Systems, Tokyo, Japan) with an over-couch X-ray system was used. Fluoroscopy-associated scattered radiation was measured using a water phantom placed at the locations of the endoscopist, assistant, nurse, and clinical engineer. For each location, measurements were performed at the gonad and thyroid gland/eye levels. Comparisons were performed between with and without the additional lead shielding device and with and without a gap in the shielding device. Additionally, a clinical study was performed with 27 endoscopic retrograde cholangiopancreatography procedures.The scattered radiation dose was lower with than without additional lead shielding at all medical staff locations and decreased by 84.7%, 82.8%, 78.2%, and 83.7%, respectively, at the gonad level and by 89.2%, 86.4%, 91.2%, and 87.0%, respectively, at the thyroid gland/eye level. Additionally, the scattered radiation dose was lower without than with a gap in the shielding device at all locations.An additional lead shielding device could protect medical staff from radiation during interventional endoscopic procedures. However, gaps in protective equipment reduce effectiveness and should be eliminated.


Assuntos
Exposição Ocupacional/prevenção & controle , Exposição à Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Radiografia Intervencionista/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/estatística & dados numéricos , Fluoroscopia/efeitos adversos , Gônadas/efeitos da radiação , Humanos , Traumatismos Ocupacionais/prevenção & controle , Imagens de Fantasmas/estatística & dados numéricos , Equipamentos de Proteção/normas , Doses de Radiação , Lesões por Radiação/prevenção & controle , Proteção Radiológica/métodos , Glândula Tireoide/efeitos da radiação
3.
Proc Biol Sci ; 287(1930): 20200578, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32605522

RESUMO

Apoptosis is an evolutionarily conserved process of programmed cell death. Here, we show structural changes in the gonads caused by apoptosis during gametogenesis in the scleractinian coral, Euphyllia ancora. Anatomical and histological analyses revealed that from the non-spawning to the spawning season, testes and ovaries increased in size due to active proliferation, differentiation and development of germ cells. Additionally, the thickness and cell density of the gonadal somatic layer decreased significantly as the spawning season approached. Further analyses demonstrated that the changes in the gonadal somatic layer were caused by apoptosis in a subpopulation of gonadal somatic cells. The occurrence of apoptosis in the gonadal somatic layer was also confirmed in other scleractinian corals. Our findings suggest that decreases in thickness and cell density of the gonadal somatic layer are structural adjustments facilitating oocyte and spermary (male germ cell cluster) enlargement and subsequent gamete release from the gonads. In animal reproduction, apoptosis in germ cells is an important process that controls the number and quality of gametes. However, apoptosis in gonadal somatic cells has rarely been reported among metazoans. Thus, our data provide evidence for a unique use of apoptosis in animal reproduction.


Assuntos
Antozoários/fisiologia , Apoptose , Animais , Diploide , Feminino , Células Germinativas , Gônadas , Masculino , Oócitos , Ovário , Estações do Ano , Testículo
4.
Chemosphere ; 259: 127415, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32603964

RESUMO

Amphibians are the most endangered class of vertebrates. In this study, Xenopus laevis frogs were exposed to 0, 1 and 10 mg/L of triadimefon or triadimenol. After 14 or 28 days of exposure, high levels of triadimefon or triadimenol obstructed the growth of frogs. However, low levels of triadimefon induced the growth of females after the longer period of exposure. We also found that the antioxidant enzyme activity and LDH levels in males were higher than those in females after 28-days exposure. In histopathology tests, triadimenol exerted more effect on the ovary while triadimefon exerted more effect on the testes. Additionally, the levels of Estradiol in all 14-day treatments, except 1 mg/L triadimenol, were significantly decreased, however, there was no difference in testosterone levels. Furthermore, triadimefon and triadimenol disrupted the expression of genes controlling hormone homeostasis and reproduction, and this effect depended on the exposure time and the gender of the organism. Our experiments explored the effect of triadimefon and its metabolite on the gonads of frogs and highlighted the role that pesticides are likely to play in the global decline of amphibians.


Assuntos
Fungicidas Industriais/toxicidade , Gônadas/crescimento & desenvolvimento , Triazóis/toxicidade , Xenopus laevis/fisiologia , Animais , Feminino , Fungicidas Industriais/metabolismo , Gônadas/anatomia & histologia , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Masculino , Xenopus laevis/metabolismo
5.
Chemosphere ; 259: 127221, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32615454

RESUMO

Due to its unique properties, graphene oxide (GO) has potential for biomedical and electronic applications, however environmental contamination including aquatic ecosystem is inevitable. Moreover, potential risks of GO in aquatic life are inadequately explored. Present study was designed to evaluate GO as an endocrine disrupting chemical (EDC) using the model Japanese medaka (Oryzias latipes). GO was injected intraperitoneally (25-200 µg/g) once to breeding pairs and continued pair breeding an additional 21 days. Eggs laid were analyzed for fecundity and the fertilized eggs were evaluated for developmental abnormalities including hatching. Histopathological evaluation of gonads, liver, and kidneys was made 21 days post-injection. LD50 was found to be sex-dependent. Fecundity tended to reduce in a dose-dependent manner during early post-injection days; however, the overall evaluation showed no significant difference. The hatchability of embryos was reduced significantly in the 200 µg/g group; edema (yolk and cardiovascular) and embryo-mortality remained unaltered. Histopathological assessment identified black particles, probably agglomerated GO, in the gonads of GO-treated fish. However, folliculogenesis in stromal compartments of ovary and the composition of germinal elements in testis remained almost unaltered. Moreover, granulosa and Leydig cells morphology did not indicate any significant EDC-related effects. Although liver and kidney histopathology did not show GO as an EDC, some GO-treated fish accumulated proteinaceous fluid in hepatic vessels and induced hyperplasia in interstitial lymphoid cells (HIL) located in kidneys. GO agglomerated in medaka gonads after 21-days post-injection. However, gonad histopathology including granulosa and Leydig cells alterations were associated with GO toxicity rather than EDC effects.


Assuntos
Grafite/toxicidade , Oryzias/fisiologia , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Disruptores Endócrinos/toxicidade , Feminino , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos
6.
Environ Sci Pollut Res Int ; 27(29): 36799-36815, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32572740

RESUMO

The objective of this study was to determine how the short-term exposure to a supraphysiological concentration of waterborne 17ß-estradiol (E2) influences on melatonin (Mel) and thyroxine (T4) concentrations in plasma and E2 and 11-ketotestosterone (11-KT) concentrations in plasma and gonads in both sexes of round goby (Neogobius melanostomus) during the pre-spawning, spawning, late spawning and non-spawning phases. The experimental protocol was based on short-term, repeated exposures of fish to a supraphysiological dose of waterborne E2. Mel level was unchanged on exposure to E2 during the investigated phases, and its role in determining a time frame for spawning in both sexes of round goby seems to be stable in those conditions. T4 and sex steroids (E2 and 11-KT) were sensitive to the exposure of E2, and those changes influence gonads by accelerating oocyte development, ovulation and regression and inhibiting spermatogenesis in this species. The results demonstrate that the physiological responses of fish in all investigated phases were altered over a short window of exposure, indicating that short-term exposure to a supraphysiological dose of E2 may impact fish in the wild. Furthermore, round goby can be recommended as a very suitable model for studying endocrine disruptors, which is sensitive to even short exposure to E2.


Assuntos
Estradiol , Perciformes , Animais , Estrogênios , Feminino , Peixes , Gônadas , Masculino
7.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1873-1878, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489072

RESUMO

The present study was conducted to explore the effect of constant temperature overwintering on the growth, gonadal development and internal quality of the Wh. pigra which were in overwintering period. Wh. pigra which in overwintering period were placed in light incubator at 21 ℃, and the Wh. pigra that overwintered under natural conditions were used as control. That the changes of growth performance, gonad index, internal quality of two groups of Wh. pigra were measured at the end of the overwintering. Simultaneously the tissue slice technique was used to observe the morphological structure of the spermary and ovary of the two groups. The results showed that the body weight of constant temperature overwintering Wh. pigra which were placed in light incubator at 21 ℃ was 2.35 times that of natural overwintering Wh. pigra which overwintered under natural conditions, and the weight of female gonads of the Wh. pigra which were placed in light incubator at 21 ℃ was 11.54% higher than that of Wh. pigra which overwintered under natural conditions, and the weight of male gonads of the Wh. pigra which were placed in light incubator at 21 ℃ was 48.33% higher than that of the Wh. pigra which overwintered under natural conditions. At the same time, that vitellogenesis cells and film forming cells which in ovarian vesicles were significantly higher than those of the Wh. pigra which overwintered under natural conditions, and that spermatogonia and primary spermatocytes which in seminal vesicle were significantly higher than those of Wh. pigra which overwintered under natural conditions. Most important of all, the anti-thrombin activity of Wh. pigra which were placed in light incubator at 21 ℃ increased by 27.85% compared with the Wh. pigra that overwintered under natural conditions. In conclusion, that constant temperature can promote the growth, the development of sperm and egg cells, and the increase of anti-thrombin activity of Wh. pigra which were in overwintering period.


Assuntos
Sanguessugas , Animais , Feminino , Gônadas , Masculino , Ovário , Óvulo , Temperatura
8.
Gene ; 755: 144906, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32554048

RESUMO

The olive flounder Paralichthys olivaceus, an important marine fish, shows gender differences in growth. The mechanism on its gonadal differentiation direction affected with exogenous factors still needs to be clarified. The anti-Müllerian hormone (amh) gene is involved in fish testicular differentiation and maintenance. The aim of this study was to investigate the expression of the flounder amh in tissues and the gonads. The quantitative expression analysis results showed that it was highly expressed in the testis, especially in the testis at stages I - IV (P < 0.05). Also, amh was detected in Sertoli cells surrounding spermatogonia and peripheral seminiferous lobule of the testis with in situ hybridization (ISH) and immunohistochemistry (IHC). During the differentiation period, the amh expression in the testis of the tamoxifen treatment group (100 ppm) was higher than that in the ovary of the 17ß-estradiol (E2, 5 ppm) group, and the expression levels of amh during process of the male differentiation in the tamoxifen group were higher than those in the 17ɑ-methyltestosterone (MT, 5 ppm) group (P < 0.05). ISH results also exhibited that amh was expressed in the somatic cells that surrounded the germ cells of juvenile flounder similar to adult ones. Furthermore, the flounder gonads in the tamoxifen group maintained more germ cells and somatic cells than those in the MT group from 20 to 80 mm total length (TL). Especially, at 60 and 80 mm TL, the numbers of germ and somatic cells in the tamoxifen group were significantly higher than those in the MT group (P < 0.05). In summary, amh might initiate the process of testicular differentiation, and is involved in the early development and maintenance of testis.


Assuntos
Hormônio Antimülleriano/genética , Linguado/genética , Células de Sertoli/metabolismo , Animais , Hormônio Antimülleriano/metabolismo , Diferenciação Celular , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Gônadas/metabolismo , Hibridização In Situ/métodos , Masculino , Metiltestosterona/farmacologia , Ovário/metabolismo , Diferenciação Sexual/genética , Espermatogônias/metabolismo , Tamoxifeno/farmacologia , Testículo/metabolismo
9.
Ecotoxicol Environ Saf ; 201: 110852, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32554204

RESUMO

Maps with grey or even white spaces are still present in spite of the fact that persistent organic pollutants (POPs) are at the forefront of research in aquatic toxicology and environmental safety. This is also the case for the Mureș River basin. The intensive use of industrial substances such as polychlorinated biphenyls (PCBs) and pesticides such as organochlorine compounds (OCPs) has caused global contamination of the aquatic environment. In our study we have found very high concentrations of both PCBs (2110-169,000 ng/g lipid weight ΣPCB, 1950-166,000 ng/g lipid weight ΣPCB7) and OCPs (1130-7830 ng/g lipid weight ΣDDT, 47.6-2790 ng/g lipid weight ΣHCH, 5.53-35.6 ng/g lipid weight ΣChlordane, and 6.74-158 ng/g lipid weight HCB) in the gonad tissue of Barbus barbus (Linnaeus, 1758) males and females. Contrary to most studies where the weight, length, and lipid percentage are positively correlated with the concentration of POPs from different tissue types, we observed a downward trend for the lipid normalized concentrations of some pollutants in gonads while these indices were actually increasing. The decrease of lipid normalized POPs with the increase of CF and lipid percentage may be due to the fact that individuals are eliminating hard and soft roes every year during reproduction which could mean that some quantities of pollutants are also eliminated along with the hard and soft roes. The high POPs concentrations found in our study should be a needed wakeup call for environmentalists and a starting point in developing monitoring and management measures for these pollutants.


Assuntos
Bioacumulação , Cyprinidae/metabolismo , Monitoramento Ambiental/métodos , Gônadas/metabolismo , Rios/química , Poluentes Químicos da Água/análise , Animais , Feminino , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Masculino , Praguicidas/análise , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Romênia , Poluentes Químicos da Água/metabolismo
10.
Sci Total Environ ; 735: 139496, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32480152

RESUMO

Pyriproxyfen (PPF), a broad-spectrum insecticide known to cause reproductive and endocrine disruption in invertebrates, while the data is scarce in aquatic vertebrates. The goal of this study is to investigate the impact of PPF on reproductive endocrine system of male and female zebrafish along hypothalamus-pituitary-gonadal (HPG) axis. In brain, PPF caused significant alteration in the transcripts of erα, lhß, and cyp19b genes in male and fshß, lhß, and cyp19b genes in female zebrafish. The downstream genes of steroidogenic pathway like, star, 3ßhsd, 17ßhsd, and cyp19a expression were significantly altered in gonad of both sexes. Subsequent changes in circulatory steroid hormone levels lead to imbalance in hormone homeostasis as revealed from estradiol/testosterone (E2/T) ratio. Further, the vitellogenin transcript level was enhanced in hepatic tissues and their blood plasma content was increased in male (16.21%) and declined in female (21.69%). PPF also induced histopathological changes in gonads such as, reduction of mature spermatocytes in male and vitellogenic oocytes in female zebrafish. The altered E2/T ratio and gonadal histopathology were supported by the altered transcript levels of HPG axis genes. Overall, these findings provide new insights of PPF in zebrafish reproductive system and highlights for further investigations on its potential risks in aquatic environment.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água/farmacologia , Animais , Sistema Endócrino/efeitos dos fármacos , Feminino , Gônadas/efeitos dos fármacos , Homeostase , Hipotálamo , Masculino , Piridinas , Reprodução , Vitelogeninas , Peixe-Zebra
11.
Chemosphere ; 255: 126941, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388259

RESUMO

With the aim of evaluating health risk to hake consumers, mercury and selenium were measured in muscle, liver, gonads, kidney, and gills of 62 specimens of Merluccius productus from northern Gulf of California. Means ± confidence interval (95% confidence level) concentrations (mg kg-1 wet weight) of Hg in tissues were: gonads (1.01 ± 0.25) > muscle (0.44 ± 0.06) > gills (0.29 ± 0.04) > kidneys (0.20 ± 0.07) > liver (0.02 ± 0.004). No significant differences between sexes were found for Hg. The distribution of mean concentrations of Se (mg kg-1 wet weight) were: kidneys (4.61 ± 1.27) > liver (1.66 ± 0.22) > gonads (1.66 ± 0.75) > gills (0.86 ± 0.04) > muscle (0.40 ± 0.09). Se in gonads showed a significant difference between sex (females > males). Positive significant correlations with total length (p < 0.05) and total weight (p < 0.05) were found in the same tissue for both morphological variables: Hg in muscle, Se in muscle and Se in liver. An excess of Se over Hg (molar ratio Se:Hg > 1) was found in all tissues. The Hazard Quotient health risk index was evaluated for humans that consume muscle and gonads. The recommended Hg safe intake for adults and children were 110.0 and 33.0 g week-1, respectively for muscle; for gonads weekly consumption portions of 35.0 and 14.0 g for adults and children represent no Hg risk. There was no risk of exposure to Se.


Assuntos
Monitoramento Ambiental , Gadiformes/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , California , Criança , Exposição Dietética/estatística & dados numéricos , Feminino , Peixes , Gônadas , Humanos , Masculino , Mercúrio/análise , Músculos/metabolismo , Perciformes , Medição de Risco , Selênio/análise , Poluentes Químicos da Água/análise
12.
Environ Pollut ; 264: 114710, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417572

RESUMO

Bisphenol A (BPA), a monomer used for polycarbonate manufacture, has been widely reported as an endocrine-disrupting chemical (EDC). Among other alterations, BPA induces reproductive dysfunctionalities. Changes in the endocannabinoid system (ECS) have been recently shown to be associated with reproductive disorders. The ECS is a lipid-based signaling system (cannabinoid receptors, endocannabinoids and enzymatic machinery) involved in several physiological functions. The main goal of the present study was to assess the effects of two environmental concentrations of BPA (10 and 20 µg/L) on the ECS in 1-year old zebrafish gonads. In males, BPA increased the gonadosomatic index (GSI) and altered testicular levels of endocannabinoids as well as reduced the testicular area occupied by spermatogonia. In male liver, exposure to 20 µg/L BPA significantly increased vitellogenin (vtg) transcript levels. In female zebrafish, BPA altered ovarian endocannabinoid levels, elevated hepatic vtg mRNA levels as well as increased the percentage of vitellogenic oocytes in the ovaries. In conclusion, exposure to two environmentally relevant concentrations of BPA altered the ECS and consequently, gonadal function in both male and female zebrafish.


Assuntos
Disruptores Endócrinos/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Compostos Benzidrílicos/farmacologia , Endocanabinoides , Feminino , Gônadas/efeitos dos fármacos , Masculino , Fenóis , Reprodução , Vitelogeninas , Peixe-Zebra
13.
Gene ; 749: 144754, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32376450

RESUMO

DNA methylation is an essential epigenetic modification that significantly regulates gene expression during development and differentiation. In this study, genome-wide methylation analysis of different gonads of the large yellow croaker was performed using whole-genome bisulfite sequencing (WGBS), which has characterized DNA methylation patterns in gonad tissue and identified candidate regions for future studies. Clustering analysis revealed that male and neomale methylation patterns were close compared to female. Based on KEGG pathway analysis of differentially methylated genes, we obtained signaling pathways related to gonadal development. We further investigated the methylation status of previously reported sex determination genes, and found that these genes showed different methylation status in three types of gonads, which may provide important clues to reveal the sex determination genes in the large yellow croaker. Furthermore, combined with transcriptome analysis, we found 7 sex-related genes in three comparison groups where expression negatively correlated with methylation.


Assuntos
Metilação de DNA , Gônadas/metabolismo , Perciformes/genética , Animais , Citosina/metabolismo , Epigênese Genética , Feminino , Masculino , Perciformes/metabolismo , Regiões Promotoras Genéticas , RNA-Seq , Análise de Sequência de DNA , Processos de Determinação Sexual , Fatores de Transcrição/genética
14.
Gene ; 750: 144756, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389707

RESUMO

Noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) have been extensively studied in biological processes such as disease development, cell proliferation but remained unclear in sex differentiation in organisms. In this study, the transcriptome profiles were comparatively analyzed between male and female gonads in Mauremys mutica. A total of 8237 differentially expressed genes (DEGs), 9573 DE lncRNAs, 84 DE circRNAs and 665 DE miRNAs were identified between male and female gonads. Through gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) of the DE RNAs, it was revealed that the DE mRNAs were majorly involved in GO terms, such as 'reproduction', 'reproductive process' and the pathways of 'focal adhesion' and 'oocyte meiosis'. In addition, a co-expression network showed that the expression of gametogenesis and sex differentiation related genes, including dmrt3a, tdrd7, sox14, etc were closely associated with the levels of their corresponding ncRNAs. Intriguingly, the dmrt1 circRNA and its target mRNA were detected upregulated both in adult testis and male producing temperature (MPT) embryos. Our findings demonstrated the sexually dimorphic expression profiles of mRNAs and ncRNAs in turtle gonads, which will provide the index to find out the molecular mechanisms behind the sex differentiation in turtles, even in other environmental sex determination (ESD) species.


Assuntos
Caracteres Sexuais , Tartarugas/genética , Animais , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/genética , Ontologia Genética , Gônadas/metabolismo , Masculino , MicroRNAs/genética , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA não Traduzido/genética , Diferenciação Sexual , Transcriptoma/genética
15.
Proc Natl Acad Sci U S A ; 117(22): 12174-12181, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32409601

RESUMO

Germ cells have the ability to differentiate into eggs and sperm and must determine their sexual fate. In vertebrates, the mechanism of commitment to oogenesis following the sexual fate decision in germ cells remains unknown. Forkhead-box protein L3 (foxl3) is a switch gene involved in the germline sexual fate decision in the teleost fish medaka (Oryzias latipes). Here, we show that foxl3 organizes two independent pathways of oogenesis regulated by REC8 meiotic recombination protein a (rec8a), a cohesin component, and F-box protein (FBP) 47 (fbxo47), a subunit of E3 ubiquitin ligase. In mutants of either gene, germ cells failed to undergo oogenesis but developed normally into sperm in testes. Disruption of rec8a resulted in arrest at a meiotic pachytenelike stage specifically in females, revealing a sexual difference in meiotic progression. Analyses of fbxo47 mutants showed that this gene regulates transcription factors that facilitate folliculogenesis: LIM homeobox 8 (lhx8b), factor in the germline α (figla), and newborn ovary homeobox (nobox). Interestingly, we found that the fbxo47 pathway ensures that germ cells do not deviate from an oogenic pathway until they reach diplotene stage. The mutant phenotypes together with the timing of their expression imply that germline feminization is established during early meiotic prophase I.


Assuntos
Proteínas de Peixes/metabolismo , Células Germinativas/citologia , Gônadas/embriologia , Oogênese , Oryzias/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/fisiologia , Gônadas/metabolismo , Masculino , Meiose , Folículo Ovariano/citologia , Processos de Determinação Sexual , Espermatogênese , Espermatozoides/citologia
16.
Ann Endocrinol (Paris) ; 81(2-3): 83-88, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32340851

RESUMO

Gonad differentiation depends on a set of cellular and hormonal signals interacting in a specific order, with very precise windows of action, to contribute to the establishment of the genital tract and a male or female phenotype. Research initially focused on the stages of gonad differentiation toward testis, in particular following the identification in 1990 of the SRY factor on chromosome Y. The mechanisms involved in gonad differentiation toward ovary took longer to identify. Thanks to patients with different sexual development (DSD) and animal knock-out models, description of the cascades involved in the activation and maintenance of ovarian development has progressed considerably in recent years.


Assuntos
Gônadas/fisiologia , Ovário/fisiologia , Processos de Determinação Sexual/fisiologia , Diferenciação Sexual/genética , Animais , Diferenciação Celular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/embriologia , Gônadas/crescimento & desenvolvimento , Humanos , Masculino , Ovário/embriologia , Ovário/crescimento & desenvolvimento , Fenótipo , Desenvolvimento Sexual/genética , Desenvolvimento Sexual/fisiologia
17.
Bull Environ Contam Toxicol ; 104(6): 738-747, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32313983

RESUMO

In this study, freshwater snail (Physa acuta) was investigated to determine histopathological effects of CuSO4 on digestive gland, foot, mantle and ovotestis under laboratory conditions. The snails were exposed to different sublethal concentrations of CuSO4 (0.05 mg/L, 0.1 mg/L and 0.2 mg/L) periods of 10, 20 and 30 days. The relationship between CuSO4 concentration and mortality rate in snails was calculated as Y = 8.8 + 125.14X, R2 = 0.9444. The histopathological examinations revealed that CuSO4 caused significant histopathological changes in all the tissues of the snail. The severity of these lesions in tissues increased with increasing CuSO4 concentration and duration of exposure. The results showed that freshwater snail, Physa acuta can be considered to be a suitable bioindicator to demonstrate the toxic effect of copper in aquatic environments.


Assuntos
Sulfato de Cobre/toxicidade , Água Doce/química , Caramujos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/patologia , Relação Dose-Resposta a Droga , Gônadas/efeitos dos fármacos , Gônadas/patologia , Músculos/efeitos dos fármacos , Músculos/patologia , Caramujos/ultraestrutura , Turquia
18.
Sci Total Environ ; 726: 138522, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335401

RESUMO

Our recent study revealed some early molecular and cellular events in which 17ß-estradiol (E2) disrupted testis differentiation and resulted in feminization in Xenopus laevis (the African clawed frog), an ideal species for studying reproductive endocrine disruption by estrogenic endocrine disrupting chemicals (EDCs). On this basis, we aimed to develop multiple biomarkers for early detection of testis differentiation disruption by estrogenic EDCs in X. laevis. Tadpoles at stage 45/46 were exposed to four known estrogenic EDCs with different estrogenic activities, including E2, diethylstilbestrol (DES), mestranol (MES) and 4-n-nonyphenol (NP). At stage 53, gonadal morphological and histological changes as well as altered sex-dimorphic gene expression in gonad-mesonephros complexes (GMCs) showed that these estrogenic EDCs disrupted testis differentiation and caused feminization to different degrees. Then we measured transcriptional changes of 48 candidate genes, which are believed to be associated with E2-induced testis differentiation alterations, in GMCs at stage 50. As a result, 19 genes were found to be transcriptionally altered by all test chemicals and proposed as promising biomarkers for early detection of testis differentiation disruption by estrogenic EDCs. Finally, all biomarker responses were integrated as integrated biomarker response (IBR) index to characterize testis differentiation disruption by these estrogenic EDCs in X. laevis. Compared with the methods used in previous studies, the multiple biomarker test using X. laevis at early developmental stages largely shortens the exposure duration, thereby achieving the goal of rapid detection. Certainly, the biomarker test needs further validations in the future study.


Assuntos
Disruptores Endócrinos , Animais , Biomarcadores , Gônadas/efeitos dos fármacos , Masculino , Mesonefro , Testículo/efeitos dos fármacos , Xenopus laevis
19.
Exp Parasitol ; 213: 107887, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32224062

RESUMO

Infection with trematodes produces physiological and behavioural changes in intermediate snail hosts. One response to infection is parasitic castration, in which energy required for reproduction of the host is thought to be redirected to promote development and multiplication of the parasite. This study investigated some reproductive and biochemical parameters in the nervous (CNS) and ovotestis (OT) tissues of Biomphalaria alexandrina during the course of Schistosoma mansoni infection. Antioxidant and oxidative stress parameters including catalase (CAT), nitric oxide (NO) and lipid peroxidation (MDA) were measured. Levels of steroid hormones, including testosterone, progesterone and estradiol, were also assessed. Finally, flow cytometry was used to compare measures of apoptosis between control snails and those shedding cercariae by examining mitochondrial membrane potential with the stain 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimi-dazolylcarbocyanine iodide (JC-1) and poly(ADP-ribose) polymerase (PARP). Infection with S. mansoni caused a 47.7% reduction in the net reproductive rate (Ro) of B. alexandrina. CAT activity was increased in the CNS at 21 days post infection (dpi) but by 28 dpi it was reduced below control values. Also, CAT activity increased significantly in the OT at 14, 21 and 28 dpi. In CNS tissues, NO levels were reduced at 7 dpi, increased at 14 and 21 dpi, and reduced again at 28 dpi. The overall level of lipid peroxidation gradually increased during the course of infection to reach its highest levels at 28 dpi. Steroid hormone measurements showed that concentrations of testosterone and estradiol were reduced in the CNS tissues at 28 dpi, while those of progesterone were slightly increased in the CNS and OT tissues. The percentage of cells that positively stained with JC-1was significantly increased in CNS and OT tissues of infected snails while the percentage of cells positively stained with PARP was decreased compared to controls. Together, these findings indicate that infection initiates diverse biochemical and hormonal changes leading to loss of cells responsible for egg laying and reproduction in B. alexandrina.


Assuntos
Biomphalaria/parasitologia , Interações Hospedeiro-Parasita , Schistosoma mansoni/fisiologia , Animais , Cercárias/fisiologia , Gônadas/parasitologia , Sistema Nervoso/parasitologia
20.
Arch Environ Contam Toxicol ; 79(1): 156-166, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32266455

RESUMO

The biological effects of endocrine-active compounds and increasing water temperatures as a result of climate change have been studied extensively and independently, but there is a dearth of research to examine the combined effect of these factors on exposed organisms. Recent data suggest that estrogenic exposure and rising ambient temperatures independently impact predator-prey relationships. However, establishing these connections in natural settings is complex. These obstacles can be circumvented if biomarkers of estrogenic exposure in resident fish can predict changes in predator-prey relationships. To test the effects of estrone and temperature, the piscivore bluegill sunfish (Lepomis macrochirus) was exposed for 30 days to estrone at concentrations (90 ± 17.6 ng/L [mean ± standard deviation] and 414 ± 146 ng/L) previously shown to reduce prey-capture success. Exposures were conducted at four temperatures (15 °C, 18 °C, 21 °C, 24 °C) to simulate breeding season ambient temperatures across the natural range of this species. A suite of morphological and physiological biomarkers previously linked to estrogenic exposures were examined. Biomarkers of estrone exposure were more commonly and severely impacted in male fish than in female fish. Notably, the gonadosomatic index was lower and gonads were less mature in exposed males. Additionally, temperature modulated the effects of estrone similarly in males and females with fish exposed at higher temperatures typically exhibiting a decreased morphological index. This study provides evidence that alterations in hepatic function and gonadal function may cause shifts in metabolism and energy allocation that may lead to declining prey capture performance.


Assuntos
Biomarcadores/metabolismo , Disruptores Endócrinos/toxicidade , Estrona/toxicidade , Água Doce/química , Perciformes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Comportamento Predatório/efeitos dos fármacos , Temperatura
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