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1.
Chemosphere ; 249: 126224, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32088463

RESUMO

To assess the toxic effects of 3-(4-Methylbenzylidene) camphor (4-MBC) at environmentally relevant concentrations on the reproduction and development of Japanese medaka (Oryzias latipes), adult paired medaka (F0) were exposed to 5, 50, and 500 µg/L 4-MBC for 28 d in the current study. The fecundity and fertility were significantly decreased at 500 µg/L 4-MBC (p < 0.05). Histological observations showed that spermatogenesis in F0 males was significantly inhibited at 50 and 500 µg/L 4-MBC, similar to the effects obtained with all treatments of plasma 11-ketotestosterone (p < 0.05). Moreover, the plasma vitellogenin and estradiol levels in F0 females were significantly increased at 5 µg/L 4-MBC (p < 0.05). All the transcripts of hypothalamic-pituitary-gonadal (HPG) axis-related genes tested in the brains and gonads of males were significantly increased at all treatments, similar to the effects obtained for erα, erß and vtg in the livers and in contrast to those found for arα in the livers (p < 0.05). Equal numbers of embryos were exposed to tap water and 4-MBC solutions. Significantly increased times to hatching, decreased hatching rates and decreased body lengths at 14-day post-hatching (dph) were obtained at 500 µg/L 4-MBC treatment (p < 0.05). The cumulative death rates at 14 dph were significantly increased with all the treatments (p < 0.05). Therefore, our results showed that long-term exposure to 50 and 500 µg/L 4-MBC causes reproductive and developmental toxicity and thus provide new insight into antiandrogenicity and the mechanism of 4-MBC in Japanese medaka.


Assuntos
Cânfora/análogos & derivados , Oryzias/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Cânfora/toxicidade , Feminino , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Reprodução/efeitos dos fármacos , Vitelogeninas
2.
Aquat Toxicol ; 221: 105441, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32045789

RESUMO

Previous studies have shown that BDE-47, one of the most abundant polybrominated diphenyl ethers (PBDEs) congeners, has a weak estrogenic activity, but it has remained unclear whether BDE-47 disrupts gonadal development and causes male-to-female sex reversal in lower vertebrates, with limited and controversial data. The present study aimed to determine the effects of BDE-47 on gonadal development in Xenopus laevis, a model amphibian species for studying adverse effects of estrogenic chemicals on reproductive development. X. laevis at stage 45/46 were exposed to BDE-47 (0.5, 5, 50 nM) in semi-static system, with 1 nM 17ß-estradiol (E2) as the positive control. When reaching stage 53, tadpoles were examined for gonadal morphology, histology and sex-dimorphic gene expression. The phenotypic sex (gonadal morphology and histology) of each BDE-47-treated tadpole matched its genetic sex, showing no sex-reversal, whereas one half of genetic males treated with E2 displayed ovarian-like features. However, some genetic males (26%) in the 50 nM BDE-47 treatment group were found to contain more germ cells clumping together in the medulla, along with an increasing tendency of the gonad length/kidney length ratio in males, resembling feminizing outcomes of E2. These observations seem to suggest that BDE-47 exerted weak feminizing effects. However, BDE-47 induced increases in expression of both female-biased genes and male-biased genes in two sexes, which disagrees with feminizing outcomes, suggesting complicated effects of BDE-47 on gonadal development. Taken together, all results demonstrate that nanomolar BDE-47 disrupted gonadal development and exerted weak feminizing effects, but not resulted in male-to-female sex reversal in X. laevis.


Assuntos
Gônadas/efeitos dos fármacos , Éteres Difenil Halogenados/toxicidade , Diferenciação Sexual/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Estradiol/toxicidade , Feminino , Gônadas/crescimento & desenvolvimento , Humanos , Larva/efeitos dos fármacos , Masculino , Reprodução/efeitos dos fármacos , Diferenciação Sexual/genética , Xenopus laevis
3.
Chemosphere ; 242: 125285, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896209

RESUMO

The aim of this study was to assess the long-term effects of synthetic progestin norethindrone (NET) on the growth, reproductive histology, and transcriptional expression profiles of genes associated with the hypothalamic-pituitary-gonadal (HPG) axis and germ cells in adult zebrafish. Adult zebrafish were exposed to 7, 84 and 810 ng/L NET for 90 days. The results showed that exposure to 810 ng/L NET caused a significant decrease in growth of females and males. The ovary weight and GSI was significantly reduced by NET at concentrations of 84 or 810 ng/L, which came along with the delay of ovary maturation in females. However, NET at all treatments resulted in acceleration of sperm maturation in males. In the ovaries of females, a strong inhibition of cyp19a1a gene was observed following exposure to NET at 810 ng/L. Similarly, NET at the highest treatment led to a significant down-regulation of cyp17, cyp19a1a, vasa, nanos1, dazl and dmc1 genes in the testes of males. Taken together, the overall results demonstrated that NET could impact growth and gonadal maturation, with significant alterations of transcriptional expression genes along HPG axis and germ cells.


Assuntos
Expressão Gênica/efeitos dos fármacos , Noretindrona/toxicidade , Progestinas/toxicidade , Poluentes Químicos da Água/toxicidade , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Animais , Regulação para Baixo , Feminino , Células Germinativas/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Masculino , Ovário/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Testículo/efeitos dos fármacos , Peixe-Zebra/genética
4.
Ecotoxicol Environ Saf ; 188: 109912, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706240

RESUMO

Synthetic progestins are emerging contaminants of the aquatic environment with endocrine disrupting potential. The main aim of the present study was to investigate the effects of the synthetic progestins gestodene, and drospirenone on sex differentiation in common carp (Cyprinus carpio) by histological analysis. To gain insights into the mechanisms behind the observations from the in vivo experiment on sex differentiation, we analyzed expression of genes involved in hypothalamus-pituitary-gonad (HPG) and hypothalamus-pituitary-thyroid (HPT) axes, histology of hepatopancreas, and in vitro bioassays. Carp were continuously exposed to concentrations of 2 ng/L of single progestins (gestodene or drospirenone) or to their mixture at concentration 2 ng/L of each. The exposure started 24 h after fertilization of eggs and concluded 160 days post-hatching. Our results showed that exposure of common carp to a binary mixture of drospirenone and gestodene caused increased incidence of intersex (32%) when compared to clean water and solvent control groups (both 3%). Intersex most probably was induced by a combination of multiple modes of action of the studied substances, namely anti-gonadotropic activity, interference with androgen receptor, and potentially also with HPT axis or estrogen receptor.


Assuntos
Androstenos/toxicidade , Carpas/crescimento & desenvolvimento , Disruptores Endócrinos/toxicidade , Norpregnenos/toxicidade , Diferenciação Sexual/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Hepatopâncreas/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Diferenciação Sexual/genética
5.
Chemosphere ; 240: 124970, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726584

RESUMO

Measurement of specific biomarkers identified by proteomics provides a potential alternative method for risk assessment, which is required to discriminate between hepatotoxicity and endocrine disruption. In this study, adult zebrafish (Danio rerio) were exposed to the hepatotoxic substance acetaminophen (APAP) for 21 days, in a fish short-term reproduction assay (FSTRA). The molecular changes induced by APAP exposure were studied in liver and gonads by applying a previously developed combined FSTRA and proteomics approach. We observed a significant decrease in egg numbers, an increase in plasma hyaluronic acid, and the presence of single cell necrosis in liver tissue. Furthermore, nine common biomarkers (atp5f1b, etfa, uqcrc2a, cahz, c3a.1, rab11ba, mettl7a, khdrbs1a and si:dkey-108k21.24) for assessing hepatotoxicity were detected in both male and female liver, indicating hepatic damage. In comparison with exposure to fadrozole, an endocrine disrupting chemical (EDC), three potential biomarkers for liver injury, i.e. cahz, c3a.1 and atp5f1b, were differentially expressed. The zebrafish proteome response to fadrozole exposure indicated a significant regulation in estrogen synthesis and perturbed binding of sperm to zona pellucida in the ovary. This study demonstrates that biomarkers identified and quantified by proteomics can serve as additional weight-of-evidence for the discrimination of hepatotoxicity and endocrine disruption, which is necessary for hazard identification in EU legislation and to decide upon the option for risk assessment.


Assuntos
Biomarcadores/análise , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental/métodos , Proteômica/métodos , Acetaminofen/metabolismo , Acetaminofen/toxicidade , Animais , Biomarcadores/metabolismo , Diagnóstico Diferencial , Fadrozol/toxicidade , Feminino , Gônadas/efeitos dos fármacos , Masculino , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
6.
Chemosphere ; 240: 124900, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563099

RESUMO

Spirotetramat (SPT) is a new tetronic acid derivative insecticide used to control scales and aphids; the potential for endocrine disruptor effects in fish could not be finalized with the available data. In this study, zebrafish were selected to assess the endocrine-disrupting effects. Significant decrease of plasma estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT) were observed in both male and female following the spirotetramat exposure; the vitellogenin (VTG) level in females significantly decreased. The expression of the hypothalamic-pituitary-gonad (HPG) axis genes fshr, lhr and esr1 showed significant increase in the gonads, which expression in males is higher than in females. In addition, the activities of capspase-3 and caspase-9 significantly decreased in both males and females liver, while the capspase-3 and caspase-9 were increased in male testis, the mRNA expression levels of genes expression related to the apoptosis pathway were also significantly altered after the spirotetramat exposure. Additionally, we found the parental zebrafish exposed to spirotetramat induced the development delay of its offspring. Above all, the adverse effects induced by spirotetramat suggesting that spirotetramat is a potential exogenous hazardous agent.


Assuntos
Compostos Aza/toxicidade , Inseticidas/toxicidade , Compostos de Espiro/toxicidade , Animais , Apoptose , Disruptores Endócrinos/toxicidade , Estradiol/metabolismo , Estrogênios/farmacologia , Feminino , Expressão Gênica , Gônadas/efeitos dos fármacos , Fígado/metabolismo , Masculino , Testículo/efeitos dos fármacos , Testosterona/análogos & derivados , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
7.
Environ Pollut ; 258: 113748, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31874432

RESUMO

Soil contaminants can cause direct harm to lizards due to their regular swallowing of soil particles. As the world's fastest growing insecticide with long half-life in soil, the endocrine disrupting effect of neonicotinoids on lizards deserves more attention. In this report, we assessed the endocrine disrupting effect of imidacloprid on Eremias argus during 28 days of continuous exposure. Among the imidacloprid and its metabolites, only the metabolite 6-chloropyridic acid had a significant accumulation in the gonads and was positively correlated with its blood concentration. Imidacloprid might cause endocrine disrupting effects on lizards in two ways. First, the desnitro metabolites of imidacloprid could accumulate in the brain, inhibited the secretion of gonadotropin-releasing hormone, and ultimately affected the feedback regulation of hypothalamic-pituitary-gonadal related hormones. Secondly, imidacloprid severely inhibited the gene expression of the corresponding enzymes in the gonadal anti-oxidative stress system, causing histological damage to the gonads and ultimately affecting gonadal function. Specifically, exposure to imidacloprid resulted in abnormal arrangement of spermatogenic epithelial epithelium, hyperplasia of epididymal wall, and oligospermia of male lizard. Meanwhile, gene expressions of cyp17, cyp19, and hsd17ß were severely inhibited in the imidacloprid exposure group, consistent with decreased levels of testosterone and estradiol in plasma. Imidacloprid exposure could cause insufficient androgen secretion and less spermatogenesis in male lizards. The risk of imidacloprid exposure to female lizards was not as severe as that of male lizards, but it still inhibited the expression of cyp19 in the ovaries and led to a decrease in the synthesis of estradiol. This study firstly reported the endocrine disruption of imidacloprid to lizards, providing new data for limiting the use of neonicotinoids.


Assuntos
Gônadas/efeitos dos fármacos , Lagartos , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Poluentes do Solo/toxicidade , Animais , Estradiol/sangue , Feminino , Masculino , Testosterona/sangue , Testes de Toxicidade
8.
Aquat Toxicol ; 217: 105327, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31703940

RESUMO

Numerous anthropogenic sources, such as pulp mill and sewage treatment effluents, contain androgenic endocrine disrupting compounds that alter the reproductive status of aquatic organisms. The current study injected adult male mummichog (Fundulus heteroclitus) with 0 (control), 1 pg/g, 1 ng/g or 1 µg/g body weight of the model androgen 5α-dihydrotestosterone (DHT) with the intent to induce a period of plasma sex hormone depression, a previously-observed effect of DHT in fish. A suite of gonadal steroidogenic genes were assessed during sex hormone depression and recovery. Fish were sampled 6, 12, 16, 18, 24, 30 and 36 h post-injection, and sections of testis tissue were either snap frozen immediately or incubated for 24 h at 18 °C to determine in vitro gonadal hormone production and then frozen. Plasma testosterone (T) and 11-ketotestosterone (11KT) were depressed beginning 24 h post-injection. At 36 h post-injection plasma T remained depressed while plasma 11KT had recovered. In snap frozen tissue there was a correlation between plasma sex hormone depression and downregulation of key steroidogenic genes including steroidogenic acute regulatory protein (star), cytochrome P450 17a1 (cyp17a1), 3ß-hydroxysteroid dehydrogenase (3ßhsd), 11ß-hydroxysteroid dehydrogenase (11ßhsd) and 17ß-hydroxysteroid dehydrogenase (17ßhsd). Similar to previous studies, 3ßhsd was the first and most responsive gene during DHT exposure. Gene responses from in vitro tissue were more variable and included the upregulation of 3ßhsd, 11ßhsd and star during the period of hormone depression. The differential expression of steroidogenic genes from the in vitro testes compared to the snap frozen tissues may be due to the lack of regulators from the hypothalamo-pituitary-gonadal axis present in whole-animal systems. Due to these findings it is recommended to use snap frozen tissue, not post-incubation tissue from in vitro analysis, for gonadal steroidogenic gene expression to more accurately reflect in vivo responses.


Assuntos
Di-Hidrotestosterona/toxicidade , Fundulidae/fisiologia , 17-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Di-Hidrotestosterona/sangue , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Masculino , Fosfoproteínas/metabolismo , Reprodução/efeitos dos fármacos , Esteroide 17-alfa-Hidroxilase/metabolismo , Testículo/efeitos dos fármacos , Testosterona/análogos & derivados , Testosterona/metabolismo , Poluentes Químicos da Água/toxicidade
9.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3239-3245, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602878

RESUMO

The present study was conducted to explores the effects of short-term addition of 17ß-E2 on the growth,gonad development and internal quality of overwintering Whitmania pigra. Before overwintering,0. 0,1. 0,10. 0,25. 0,50. 0,100. 0 µg·L~(-1) of 17ß-E2 were added to the aquaculture water for 6 weeks and then hibernated for 60 days. The changes of growth performance,gonad index,morphological structure of spermary( ovary),endogenous steroid hormones level and internal quality were measured. The results showed that the body weight,weight gain rate,specific growth rate,female gonad index,oocyte development and endogenous estrogen level of the leech increased first and then decreased with the increase of the concentration of exogenous 17ß-E2,which were higher than those of the control group. The body weight,weight gain rate and specific growth rate of the leech at the concentration of 25 µg·L~(-1)17ß-E2 were significantly higher than those of the other groups( P<0. 05),oocyte development and endogenous estrogen levels were significantly higher than those of other groups at the concentration of 50 µg·L~(-1)( P<0. 05). When the concentration of exogenous 17ß-E2 was higher than 50 µg·L~(-1),the levels of male gonad index,spermatocyte development,endogenous androgen and progesterone were significantly inhibited( P< 0. 05). There was no significant difference in endogenous corticosteroid levels among the groups. In conclusion,short-term addition of exogenous 17ß-E2 of 10-25 µg·L~(-1) could promote the growth of overwintering leeches,oocyte development and antithrombin activity without inhibiting the development of male gonads.


Assuntos
Estradiol/farmacologia , Gônadas/crescimento & desenvolvimento , Sanguessugas/efeitos dos fármacos , Sanguessugas/crescimento & desenvolvimento , Androgênios/análise , Animais , Estrogênios/análise , Feminino , Gônadas/efeitos dos fármacos , Hibernação , Masculino , Progesterona/análise
10.
Ecotoxicol Environ Saf ; 185: 109683, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31550567

RESUMO

Thiamethoxam has emerged as an environmental contaminant detected in aqueous environments, and its endocrine-disrupting effect at chronic exposure in teleosts remains unknown. In the present study, a docking experiment and an in vivo test were integrated to systematically explore the toxic mechanisms of thiamethoxam in fish. Histological analysis, plasma VTG and hormone level (E2, 11-KT, T3 and T4) determinations, and HPG and HPT gene expression quantification were performed after Chinese rare minnow (Gobiocypris rarus) was exposed to thiamethoxam (0, 0.5, 5, and 50 µg/L) for 90 days. According to the docking study, thiamethoxam had different interactions with ERα, AR and TRα via hydrogen bonding. A decrease in body length and plasma T4 was observed in both genders. The histological damage in liver and delayed gonadal development were observed in both genders at 50 µg/L thiamethoxam treatment. In males, the following HPG axis genes were upregulated: gnrh and cyp19b in the brain; vtg and cyp19a in the liver; and cyp17 and cyp19a in the gonad. In females, erɑ in the liver was significantly upregulated with 0.5 µg/L thiamethoxam treatment, and cyp17 in the gonad was upregulated with all treatment. The suppression of cyp19a, gnrh, cyp11a, and ttr was observed at the concentration of 5 µg/L in the female liver. Taken together, the endocrine system of Chinese rare minnow might be disrupted after chronic exposure to thiamethoxam.


Assuntos
Cyprinidae/metabolismo , Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Hormônios/metabolismo , Tiametoxam/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Cyprinidae/genética , Sistema Endócrino/metabolismo , Feminino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Simulação de Acoplamento Molecular , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Regulação para Cima , Vitelogeninas/metabolismo
11.
Aquat Toxicol ; 215: 105289, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31491707

RESUMO

Mifepristone (RU486), a clinical abortion agent and potential endocrine disruptor, binds to progestin and glucocorticoid receptors and has multiple functional importance in reproductive physiology. A long-term exposure of RU486 resulted in masculinization of female fish, however, the epigenetic landscape remains elusive. Recent studies demonstrated that long non-coding RNAs (lncRNAs) might play potential roles in epigenetic modulation of sex differentiation, ovarian cancer and germline stem cell survival. To further understand the influence of RU486 exposure on epigenetic regulation, we performed a comparative investigation on sex-biased gonadal lncRNAs profiles using control XX/XY and RU486-induced sex reversed XX Nile tilapia (Oreochromis niloticus) by RNA-seq. In total, 962 sexually differentially expressed lncRNAs and their target genes were screened from the gonads of control and sex reversed fish. In comparison with the control XX group, sex reversal induced by RU486 treatment led to significant up-regulation of 757 lncRNAs and down-regulation of 221 lncRNAs. Hierarchical clustering analysis revealed that global lncRNA expression profiles in RU486-treated XX group clustered into the same branch with the control XY, whereas XX control group formed a separate branch. The KEGG pathway enrichment analysis showed that the cis-target genes between RU486-XX and control-XX were concentrated in NOD - like receptor signaling pathway, Cell adhesion molecules (CAMs) and Biosynthesis of amino acids. Real-time PCR and in situ hybridization experiments demonstrate that lncRNAs showing intense fluctuation during RU486 treatment are also sexually dimorphic during early sex differentiation, which further proves the intimate relationship between lncRNAs and sex differentiation and sexual transdifferentiation. Taken together, our data strongly indicates that a long-term exposure of RU486 resulted in sex reversal of XX female fish and the altered expression of sexually dimorphic lncRNAs might partially account for the sex reversal via epigenetic modification.


Assuntos
Ciclídeos/genética , Ciclídeos/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Gônadas/metabolismo , Mifepristona/toxicidade , Progestinas/antagonistas & inibidores , RNA Longo não Codificante/genética , Caracteres Sexuais , Animais , Feminino , Genoma , Gônadas/efeitos dos fármacos , Masculino , Fases de Leitura Aberta/genética , Ovário/efeitos dos fármacos , Ovário/metabolismo , RNA Longo não Codificante/metabolismo , Reprodutibilidade dos Testes , Testículo/efeitos dos fármacos , Testículo/metabolismo , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
12.
Bull Environ Contam Toxicol ; 103(5): 729-733, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31531704

RESUMO

Accumulation of nonylphenol (NP) in hepatopancreas, gonad, eyestalk, and muscle of freshwater prawn Macrobrachium rosenbergii following 72 h exposure to 100 µg/L NP, and depuration of NP in these tissues at 0.5-192 h post exposure were examined. We also examined the expressions of vitellogenin (Vg) and vitellogenin receptor (VgR) of prawn following 0-20 days exposure to 0, 1, 10, and 100 µg/L NP. NP accumulation in hepatopancreas and gonad with high concentration, and low concentration in muscle, but depurated faster in eyestalk and muscle. The expressions of vitellogenin (Vg) and vitellogenin receptor (VgR) increased directly with dose and time. In conclusion, NP accumulated significantly in gonad together with high Vg and VgR expressions, and depurated slow in hepatopancreas and gonad when prawns were removed back to control water. The induction of Vg and VgR under NP exposure might be a stress response in M. rosenbergii.


Assuntos
Proteínas do Ovo/genética , Água Doce/química , Palaemonidae/efeitos dos fármacos , Fenóis/toxicidade , Receptores de Superfície Celular/genética , Vitelogeninas/genética , Poluentes Químicos da Água/toxicidade , Animais , 32418/efeitos dos fármacos , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Taxa de Depuração Metabólica , Palaemonidae/metabolismo , Fenóis/metabolismo , Poluentes Químicos da Água/metabolismo
13.
Ecotoxicol Environ Saf ; 183: 109527, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31400723

RESUMO

Eutrophication is an ecological process that results in cyanobacterial blooms. Microcystin-LR is the most toxic variant of microcystins and may cause toxic effects in the organisms, mainly in hepatic tissues. The aims of this study were to use multiple biomarkers in order to evaluate the sublethal effects of a low concentration of MC-LR (1 µg/L) in fish Geophagus brasiliensis by waterborne exposure; and evaluate the depuration of this toxin during 15 days. A group of 30 fish was exposed to 1 µg/L of MC-LR solution for 96 h in a static bioassay. After this time, blood, brain, muscle, liver, gonad and gills were collected from half of the exposed fish group in order to evaluate chemical, biochemical, histological and genotoxic biomarkers. The rest of the fish group was submitted to the depuration experiment with free MC-LR water for 15 days. After this time the same tissues were collected and evaluated using biomarkers analysis. Toxic effects were found mostly in the fish liver from depuration time as alterations on the antioxidant system and histopathologies. The results showed that even low concentrations can cause sublethal effects to aquatic organisms, and cyanotoxins monitoring and regulation tools are required.


Assuntos
Ciclídeos/metabolismo , Microcistinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Ciclídeos/sangue , Ciclídeos/genética , Relação Dose-Resposta a Droga , Eutrofização , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Taxa de Depuração Metabólica , Microcistinas/metabolismo , Especificidade de Órgãos , Alimentos Marinhos , Poluentes Químicos da Água/metabolismo
14.
Mar Biotechnol (NY) ; 21(5): 697-706, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372794

RESUMO

The availability of sexually mature fish often dictates the success of its captive breeding. In this study, we induced reproductive development in juvenile protogynous tiger grouper through oral administration of a plasmid (p) containing an engineered follicle-stimulating hormone (FSH). An expression construct (pcDNA3.1) was designed to express a single-chain FSH consisting of giant grouper FSH ß-subunit and glycoprotein subunit-α (CGα), linked by the carboxy-terminal peptide (CTP) sequence from the human chorionic gonadotropin (hCG). Single oral delivery of pFSH encapsulated in liposome and chitosan to tiger grouper yielded a significant increase in plasma FSH protein level after 4 days. Weekly pFSH feeding of juvenile tiger groupers for 8 weeks stimulated ovarian development as indicated by a significant increase in oocyte diameter and progression of oocytes to cortical alveolar stage. As the pFSH treatment progressed from 20 to 38 weeks, female to male sex change was initiated, characterized by oocyte regression, proliferation of spermatogonial cells, and occurrence of spermatogenic cysts. It was also associated with significantly lower mRNA expression of steroidogenic genes (cyp11b, cyp19a1a, and foxl2) and basal plasma levels of sex steroid hormones 17ß-estradiol (E2), testosterone (T), and 11-ketotestosterone (11KT). Results suggest that pFSH stimulates ovarian development up to cortical alveolar stage and then initiates sex change in tiger grouper. These findings significantly contribute to our knowledge on the role of FSH in the development of protogynous hermaphroditic fish. This study is the first to demonstrate induction of reproductive development in fish through oral delivery of plasmid gonadotropin.


Assuntos
Gonadotropina Coriônica/genética , Hormônio Foliculoestimulante/genética , Gônadas/efeitos dos fármacos , Organismos Hermafroditas/efeitos dos fármacos , Perciformes/genética , Processos de Determinação Sexual/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Administração Oral , Animais , Quitosana/química , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/biossíntese , Composição de Medicamentos , Feminino , Proteínas de Peixes/biossíntese , Proteínas de Peixes/genética , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/biossíntese , Hormônios Esteroides Gonadais/biossíntese , Hormônios Esteroides Gonadais/genética , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Organismos Hermafroditas/genética , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Masculino , Oogênese/efeitos dos fármacos , Oogênese/genética , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Pré-Seleção do Sexo/métodos , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética
15.
Bull Environ Contam Toxicol ; 103(3): 400-404, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31352602

RESUMO

This study aimed to investigate the impact of estrogenic endocrine disruptors in adult male Nile Tilapia (Oreochromis niloticus) from the Seven Lakes (Bunot, Calibato, Mohicap, Palakpakin, Pandin, Sampaloc and Yambo) of San Pablo City in Laguna, Philippines. Fish were collected from aquaculture operations in each lake from July to September 2017 and examined for plasma vitellogenin (VTG) levels, hepatosomatic index (HSI) and gonadosomatic index (GSI). In comparison to the reference group (Pandin Lake), fish from Mohicap, Sampaloc and Yambo had higher levels of plasma VTG. HSI was increased in fish from Bunot Lake while it was markedly reduced in fish from Sampaloc Lake. Comparable GSI were obtained in all samples. While most examined fish are in active spermatogenesis, fish from Sampaloc Lake had immature gonads with no spermatozoa, and with minimal to moderate Leydig cell vacuolation and hyperplasia. The results suggest that cultured Nile tilapia from Sampaloc Lake is most adversely affected by endocrine-active compounds. The identification and quantification of these chemicals are recommended in future studies.


Assuntos
Ciclídeos/fisiologia , Estrogênios/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Aquicultura , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Estrogênios/análise , Gônadas/efeitos dos fármacos , Lagos/química , Masculino , Filipinas , Inquéritos e Questionários , Vitelogeninas/sangue , Poluentes Químicos da Água/análise
16.
Environ Toxicol ; 34(11): 1255-1262, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31298479

RESUMO

Progesterone (P4) is a biologically active steroid hormone that is involved in the regulation of oocyte growth and maturation, as well as development of the endometrium and implantation in the uterus of humans. It can also stimulate oocyte maturation in female fish, as well as spermatogenesis and sperm motility in male fish. Thus, P4 has been extensively used in human and animal husbandry as a typical progestin. However, P4 remaining in the water environment will pose a potential hazard to aquatic organisms. For example, it can interfere with sex differentiation and reproduction in aquatic vertebrates such as fish. Therefore, we investigated the effects of prolonged progesterone exposure on the expression of genes related to circadian rhythm signaling and the hypothalamic-pituitary-gonadal (HPG) axes in Yellow River Carp, which may have a potential impact on their sex differentiation. Our results suggested that P4 exposure altered the expression of genes related to circadian rhythm signaling, which can lead to disorders in the endocrine system and regulate the HPG axes-related activities. Furthermore, the expression of genes related to the HPG axes was also altered, which might affect gonadal development and the reproductive systems of Yellow River Carp. In addition, these changes may provide a plausible mechanism for the observed shifts in their sex ratio toward females.


Assuntos
Ritmo Circadiano/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Progesterona/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Carpas/crescimento & desenvolvimento , Carpas/metabolismo , Feminino , Gônadas/efeitos dos fármacos , Gônadas/patologia , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Diferenciação Sexual/efeitos dos fármacos , Razão de Masculinidade , Transcrição Genética/efeitos dos fármacos
17.
BMC Genomics ; 20(1): 587, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315571

RESUMO

BACKGROUND: Atrazine is widely used in agriculture and is a known endocrine disrupting chemical. Atrazine can seep into the water body through surface, posing a potential threat to the aquatic ecological environment and human drinking water source. In vertebrate, studies have shown that it can affect reproduction and development seriously, but its molecular mechanism for aquatic animals is unknown. Aquaculture is very common in China, especially common carp, whose females grow faster than males. However, the effects of atrazine on the reproduction of carp, especially miRNA, have not been investigated. RESULTS: In this study, common carp (Cyprinus carpio) at two key developmental stages were exposed to atrazine in vitro. Sex ratio was observed to analyze the effect of atrazine on the sex. MiRNA expression profiles were analysed to identify miRNAs related to gonad development and to reveal the atrazine mechanisms interfering with gonad differentiation. The results showed that the sex ratio was biased towards females. Atrazine exposure caused significant alteration of multiple miRNAs. Predicted targets of differently-expressed miRNAs were involved in many reproductive biology signalling pathways. CONCLUSIONS: Our results indicate that atrazine promoted the expression of female-biased genes by decreasing miRNAs in primordial gonad. In addition, our results indicate that atrazine can up-regulate aromatase expression through miRNAs, which supports the hypothesis that atrazine has endocrine-disrupting activity by altering the gene expression profile of the Hypothalamus-Pituitary-Gonad axis through its corresponding miRNAs.


Assuntos
Atrazina/toxicidade , Carpas/genética , Disruptores Endócrinos/toxicidade , Gônadas/efeitos dos fármacos , MicroRNAs/genética , Diferenciação Sexual/efeitos dos fármacos , Animais , Aromatase/genética , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Gônadas/embriologia , Masculino , Razão de Masculinidade , Transcriptoma/efeitos dos fármacos
18.
Chemosphere ; 237: 124422, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31352104

RESUMO

Environmental estrogenic compounds are important pollutants, which are widely distributed in natural water bodies. They produce various adverse effects on fish, but their concentration-dependent toxicities in fish metabolism and health are not fully understood. This study investigated the effects of 17ß-estradiol (E2) and bisphenol A (BPA) at low and high concentrations on lipid deposition, inflammation and antioxidant response in male zebrafish. We measured fish growth parameters, gonad development, lipid contents and the activities of inflammatory and antioxidant enzymes, as well as their mRNA expressions. All E2 and BPA concentrations used increased body weight, damaged gonad structure and induced feminization in male zebrafish. The exposure of zebrafish to E2 and BPA promoted lipid accumulation by increasing total fat, liver triglycerides and free fatty acid contents, and also upregulated lipogenic genes expression, although they decreased total cholesterol content. Notably, zebrafish exposed to low concentrations of E2 (200 ng/L) and BPA (100 µg/L) had higher lipid synthesis and deposition compared to high concentrations (2000 ng/L and 2000 µg/L, respectively). However, the high concentrations of E2 and BPA increased inflammation and antioxidant response. Furthermore, BPA caused greater damage to fish gonad development and more severe lipid peroxidation compared to E2. Overall, the results suggest that the toxic effects of E2 and BPA on zebrafish are concentration-dependent such that, the relative low concentrations used induced lipid deposition, whereas the high ones caused adverse effects on inflammation and antioxidant response.


Assuntos
Antioxidantes/metabolismo , Compostos Benzidrílicos/farmacologia , Estradiol/farmacologia , Inflamação/induzido quimicamente , Metabolismo dos Lipídeos/efeitos dos fármacos , Fenóis/farmacologia , Poluentes Químicos da Água/toxicidade , Animais , Compostos Benzidrílicos/metabolismo , Relação Dose-Resposta a Droga , Estradiol/metabolismo , Estrogênios/farmacologia , Gônadas/efeitos dos fármacos , Inflamação/metabolismo , Masculino , Fenóis/metabolismo , Diferenciação Sexual , Peixe-Zebra/metabolismo
19.
Regul Toxicol Pharmacol ; 108: 104424, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31330157

RESUMO

The fish short-term reproduction assay (FSTRA) is an in vivo screen to assess potential interactions with the fish endocrine system. After a 21-day exposure period vitellogenin (VTG) and secondary sexual characteristics are measured in males and females. Egg production and fertility are also monitored daily throughout the test. This paper presents data from 49 studies performed to satisfy test orders from the United States Environmental Protection Agency's Endocrine Disruptor Screening Program. Data Evaluation Records were used to collate the typical control variability and performance of test parameters in FSTRAs conducted in different laboratories with fathead minnow (Pimephales promelas). We also examine the statistical power of FSTRA endpoints and assess whether available historical control data (HCD) assist evidence-based interpretation of the endpoints. Statistically significant inter-laboratory differences were found for all endpoints except survival. HCD could therefore be usefully developed on a laboratory-by-laboratory basis to aid interpretation of new study data. Reliable HCD ranges could be developed for survival, body weight/length, gonadal somatic index, fertilisation success, and male tubercle score, and used in association with stated test acceptability criteria to interpret FSTRA data. In contrast, high intra- and inter-laboratory control variability for VTG and fecundity means that HCD for these endpoints are of limited use during study interpretation.


Assuntos
Bioensaio , Grupos Controle , Disruptores Endócrinos/toxicidade , Reprodução/efeitos dos fármacos , Testes de Toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Cyprinidae , Feminino , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Laboratórios , Masculino , Reprodutibilidade dos Testes , Vitelogeninas/metabolismo
20.
Environ Pollut ; 249: 1049-1059, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31146311

RESUMO

Tebuconazole is a widely used fungicide that has been detected in water ecosystems, of which the concentrations may affect the endocrine function of aquatic organisms. At present study, tissue-specific bioaccumulation of tebuconazole was found in ovary of adult zebrafish, indicating a potential risk of endocrine disruption. In order to evaluate the potential endocrine disrupting effects, three life stages (2 hpf (hours post-fertilization) -60 dpf (days post-fertilization), Stage I; 60-120 dpf, Stage II; 180-208 dpf, Stage III) of zebrafish (Danio rerio) were chronically exposed to tebuconazole at the concentrations ranging from 0.05 mg/L to 1.84 mg/L. Result showed that exposed to tebuconazole could lead to a male-biased sex differentiation in juvenile zebrafish and significant decrease of the percentage of germ cells in sexually-mature zebrafish. Egg production was significantly inhibited by 57.8% and 19.2% after Stage II- and Stage III-exposures, respectively. The contents of 17ß-estradiol in gonad decreased by 63.5% when exposed to 0.20 mg/L tebuconazole at Stage II and by 49.5% after exposed to 0.18 mg/L tebuconazole at Stage III, respectively. For all stages exposure, reductions in 17ß-estradiol/testosterone ratio were observed, indicating an imbalance in steroids synthesis. Additionally, tebuconazole reduced the expression of cyp19a, which was consistent with the decrease of E2 level. In overall, the present findings indicated that, playing as an anti-estrogen-like chemical, tebuconazole inhibited the expression of Cyp19, thereby impairing steroid hormones biosynthesis, leading to a diminished fecundity of zebrafish.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Fungicidas Industriais/toxicidade , Gônadas/efeitos dos fármacos , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Aromatase/metabolismo , Embrião não Mamífero/metabolismo , Disruptores Endócrinos/metabolismo , Feminino , Fungicidas Industriais/metabolismo , Gônadas/embriologia , Diferenciação Sexual/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Triazóis/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
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