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1.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808818

RESUMO

Dichlorodiphenyltrichloroethane (DDT) is the most widespread, persistent pollutant and endocrine disruptor on the planet. Although DDT has been found to block androgen receptors, the effects of its low-dose exposure in different periods of ontogeny on the male reproductive system remain unclear. We evaluate sex steroid hormone production in the pubertal period and after maturation in male Wistar rats exposed to low doses of o,p'-DDT, either during prenatal and postnatal development or postnatal development alone. Prenatally and postnatally exposed rats exhibit lower testosterone production and increased estradiol and estriol serum levels after maturation, associated with the delayed growth of gonads. Postnatally exposed rats demonstrate accelerated growth of gonads and higher testosterone production in the pubertal period. In contrast to the previous group, they do not present raised estradiol production. All of the exposed animals exhibit a reduced conversion of progesterone to 17OH-progesterone after sexual maturation, which indicates putative attenuation of sex steroid production. Thus, the study reveals age-dependent outcomes of low-dose exposure to DDT. Prenatal onset of exposure results in the later onset of androgen production and the enhanced conversion of androgens to estrogens after puberty, while postnatal exposure induces the earlier onset of androgen secretion.


Assuntos
Androgênios/biossíntese , DDT/farmacologia , Disruptores Endócrinos/farmacologia , Exposição Ambiental/efeitos adversos , Estrogênios/biossíntese , Animais , DDT/administração & dosagem , Disruptores Endócrinos/administração & dosagem , Feminino , Genitália Masculina/efeitos dos fármacos , Genitália Masculina/metabolismo , Hormônios Esteroides Gonadais/biossíntese , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Masculino , Ratos
2.
Eur J Endocrinol ; 184(5): K11-K14, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33667194

RESUMO

Objective: The role of miRNA as endocrine regulators is emerging, and microRNA mir-30b has been reported to repress Mkrn3. However, the expression of miR-30b during male puberty has not been studied. Design and methods: Circulating relative miR-30b expression was assessed in sera of 26 boys with constitutional delay of growth and puberty (CDGP), treated with low-dose testosterone (T) (n =11) or aromatase inhibitor letrozole (Lz) (n =15) for 6 months and followed up to 12 months (NCT01797718). The associations between the relative expression of miR-30b and hormonal markers of puberty were evaluated. Results: During the 12 months of the study, circulating miR-30b expression increased 2.4 ± 2.5 (s.d.) fold (P = 0.008) in all boys, but this change did not correlate with corresponding changes in LH, testosterone, inhibin B, FSH, or testicular volume (P = 0.25-0.96). Lz-induced activation of the hypothalamic-pituitary-gonadal (HPG) axis was associated with more variable miR-30b responses at 3 months (P < 0.05), whereas those treated with T exhibited significant changes in relative miR-30b levels in the course the study (P < 0.01-0.05). Conclusions: Circulating miR-30b expression in boys with CDGP increases in the course of puberty, and appears to be related to the activity of the HPG axis.


Assuntos
MicroRNAs/sangue , Puberdade/sangue , Adolescente , Quimioterapia Combinada , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Gônadas/fisiologia , Transtornos do Crescimento/sangue , Transtornos do Crescimento/complicações , Transtornos do Crescimento/tratamento farmacológico , Terapia de Reposição Hormonal , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Injeções Intramusculares , Letrozol/administração & dosagem , Letrozol/farmacologia , Estudos Longitudinais , Masculino , Puberdade/efeitos dos fármacos , Puberdade/genética , Puberdade Tardia/sangue , Puberdade Tardia/complicações , Puberdade Tardia/tratamento farmacológico , Testosterona/administração & dosagem , Testosterona/farmacologia , Ubiquitina-Proteína Ligases/genética
3.
Methods Mol Biol ; 2218: 49-60, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606222

RESUMO

The regulation of reproduction in zebrafish, the prime model of fish research, is not fully understood. An efficient tool to gain a better understanding of this complicated process is utilization of severely sex-biased families or groups. Here, we describe a method for partial depletion of primordial germ cells (PGCs) that leads to eventual masculinization of zebrafish. The technique is based on injecting early embryos with diluted morpholino oligonucleotides that temporarily interfere with the production of Dead end (Dnd), an RNA-binding protein essential for PGC survival. In addition, we also propose the use of eviscerated trunk, as a suitable alternative for examining gonadal expression in juvenile zebrafish.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Morfolinos/administração & dosagem , Oligonucleotídeos/administração & dosagem , Animais , Embrião não Mamífero/metabolismo , Feminino , Células Germinativas/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Injeções , Masculino , Proteínas de Ligação a RNA/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
4.
Environ Toxicol Pharmacol ; 83: 103596, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482285

RESUMO

The wastewater contamination of urban rivers is a concern for biodiversity and a consequence from poor urban conservation policies. In the current study, the impact of urban and industrial activities was investigated in Iguaçu river (Southern Brazil) using juvenile Oreochromis niloticus, after trophic and chronic exposure (25, 50 and 100 %), over 81 days. After exposure liver, gills, gonads, brain, muscle, and blood were sampled for chemical, biochemical, histopathological, genotoxic and molecular analyses. Water levels of persistent organic pollutants such as polychlorinated biphenyls, organochlorine pesticides, polycyclic aromatics hydrocarbon (PAHs) and metals were investigated. The redox unbalance, histopathological and increase in vitellogenin expression in fish revealed both the bioavailability of micropollutants and their harmful effects. According to the results, the level of Iguaçu river pollution negatively impacts the health of O. niloticus revealing and highlighting the risk of this pollution exposure to biota and human populations.


Assuntos
Ciclídeos , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Brasil , Catalase/metabolismo , Ciclídeos/sangue , Ciclídeos/metabolismo , Feminino , Brânquias/efeitos dos fármacos , Brânquias/patologia , Glutationa Transferase/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/patologia , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Metais Pesados/análise , Metais Pesados/toxicidade , Músculos/efeitos dos fármacos , Músculos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Carbonilação Proteica/efeitos dos fármacos , Rios , Vitelogeninas/sangue , Poluentes Químicos da Água/análise
5.
Clin Sci (Lond) ; 134(24): 3237-3257, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33346358

RESUMO

Hypertension is one of the most prevalent diseases that leads to end organ damage especially affecting the heart, kidney, brain, and eyes. Numerous studies have evaluated the association between hypertension and impaired sexual health, in both men and women. The detrimental effects of hypertension in men includes erectile dysfunction, decrease in semen volume, sperm count and motility, and abnormal sperm morphology. Similarly, hypertensive females exhibit decreased vaginal lubrication, reduced orgasm, and several complications in pregnancy leading to fetal and maternal morbidity and mortality. The adverse effect of hypertension on male and female fertility is attributed to hormonal imbalance and changes in the gonadal vasculature. However, mechanistic studies investigating the impact of hypertension on gonads in more detail on a molecular basis remain scarce. Hence, the aim of the current review is to address and summarize the effects of hypertension on reproductive health, and highlight the importance of research on the effects of hypertension on gonadal inflammation and lymphatics.


Assuntos
Gônadas/fisiopatologia , Hipertensão/fisiopatologia , Inflamação/fisiopatologia , Linfangiogênese , Reprodução/fisiologia , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Gônadas/efeitos dos fármacos , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Inflamação/complicações , Reprodução/efeitos dos fármacos
6.
Ecotoxicol Environ Saf ; 205: 111367, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32971454

RESUMO

Tebuconazole (TBZ), an azole pesticide, is one of the most frequently detected fungicides in surface water. Despite its harmful effects, mainly related to endocrine disturbance, the consequences of TBZ exposure in amphibians remain poorly understood. Here, we investigated the adverse and delayed effects of TBZ chronic exposure on a native anuran species, often inhabiting cultivated areas, the Italian tree frog (Hyla intermedia). To disclose the multiple mechanisms of action through which TBZ exerts its toxicity we exposed tadpoles over the whole larval period to two sublethal TBZ concentrations (5 and 50 µg/L), and we evaluated histological alterations in three target organs highly susceptible to xenobiotics: liver, kidney, and gonads. We also assessed morphometric and gravimetric parameters: snout-vent length (SVL), body mass (BM), liver somatic index (LSI), and gonad-mesonephros complex index (GMCI) and determined sex ratio, gonadal development, and differentiation. Our results show that TBZ induces irreversible effects on multiple target organs in H. intermedia, exerting its harmful effects through several pathological pathways, including a massive inflammatory response. Moreover, TBZ markedly affects sexual differentiation also by inducing the appearance of sexually undetermined individuals and a general delay of germ cell maturation. Given the paucity of data on the effects of TBZ in amphibians, our results will contribute to a better understanding of the environmental risk posed by this fungicide to the most endangered group of vertebrates.


Assuntos
Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Animais , Anuros/crescimento & desenvolvimento , Gônadas/efeitos dos fármacos , Larva/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos
7.
Ecotoxicol Environ Saf ; 205: 111176, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32846301

RESUMO

The effects of 17α-ethinylestradiol (EE2) on sex ratio, gonopodium morphology, and gonadal histology of C. decemmaculatus were assessed by a full-lifecycle exposure experiment. Newborn fish were waterborne exposed to 30, 100, and 300 ng EE2/L for 90 d, using 50 fish per treatment. Additionally, in December of 2016, a field survey was conducted on a C. decemmaculatus population inhabiting the Girado Creek downstream of the Chascomus city wastewater effluent discharge. After 90 d of exposure, EE2 was able to histologically skew the sex ratio toward females and inhibit the full gonopodium development since the lowest tested concentration (LOEC = 30 ng/L). At higher concentrations, EE2 was toxic, inducing mortality in a concentration-dependent fashion (90 d-LC50 = 109.9 ng/L) and altering the gonadal histoarchitecture, causing neither testes nor ovaries discernible histologically (LOEC = 100 ng/L). In addition, a novel response, perianal hyperpigmentation, was discovered been induced by the EE2 exposure in a concentration-dependent fashion (90 d-EC50 = 39.3 ng/L). A higher proportion of females and perianal hyperpigmentation were observed in wild fish collected from the Girado Creek. The major reached conclusions are: i) EE2 induce different effects on the sexual traits of C. decemmaculatus when exposed from early-life or adult stages. ii) The most sensitive effects observed in the laboratory occur in a creek receiving wastewater effluent. iii) The perianal hyperpigmentation comes-up as a promising biomarker of exposure to estrogenic compounds.


Assuntos
Ciprinodontiformes/crescimento & desenvolvimento , Disruptores Endócrinos/toxicidade , Etinilestradiol/toxicidade , Gônadas/efeitos dos fármacos , Hiperpigmentação/induzido quimicamente , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Gônadas/crescimento & desenvolvimento , Gônadas/patologia , Humanos , Estágios do Ciclo de Vida/efeitos dos fármacos , Masculino , Ovário/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ovário/patologia , Fenótipo , Razão de Masculinidade , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Testículo/patologia
8.
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
9.
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
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.
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
12.
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
13.
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
14.
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
15.
Mar Environ Res ; 156: 104904, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174334

RESUMO

This study assesses the sex-specific effects induced by CdTe QDs, on the marine mussel Mytilus galloprovincialis in comparison to its dissolved counterpart. A 14 days exposure to CdTe QDs and dissolved Cd was conducted (10 µg Cd L-1), analysing Cd accumulation, oxidative stress, biotransformation, metallothionein and oxidative damage in the gonads. Both Cd forms caused significant antioxidant alterations, whereby QDs were more pro-oxidant, leading to oxidative damage, being females more affected. Overall, biochemical impairments on gonads of M. galloprovincialis demonstrate that the reproductive toxicity induced by CdTe QDs in mussels are sex-dependent and mediated by oxidative stress and lipid peroxidation. It is crucial to acknowledge how gametes are affected by metal-based nanoparticles, such as Cd-based QDs. As well as understanding the potential changes they may undergo at the cellular level during gametogenesis, embryogenesis and larval development potentially leading to serious impacts on population sustainability and ecosystem health.


Assuntos
Compostos de Cádmio/toxicidade , Gônadas/efeitos dos fármacos , Mytilus , Pontos Quânticos/toxicidade , Telúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cádmio , Ecossistema , Peroxidação de Lipídeos , Estresse Oxidativo
16.
Gen Comp Endocrinol ; 291: 113439, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32061640

RESUMO

Anthropogenic emissions of carbon dioxide in the atmosphere have generated rapid variations in atmospheric composition which drives major climate changes. Climate change related effects include changes in physico-chemical proprieties of sea and freshwater, such as variations in water temperature, salinity, pH/pCO2 and oxygen content, which can impact fish critical physiological functions including reproduction. In this context, the main aim of the present review is to discuss how climate change related effects (variation in water temperature and salinity, increases in duration and frequency of hypoxia events, water acidification) would impact reproduction by affecting the neuroendocrine axis (brain-pituitary-gonad axis). Variations in temperature and photoperiod regimes are known to strongly affect sex differentiation and the timing and phenology of spawning period in several fish species. Temperature mainly acts at the level of gonad by interfering with steroidogenesis, (notably on gonadal aromatase activity) and gametogenesis. Temperature is also directly involved in the quality of released gametes and embryos development. Changes in salinity or water acidification are especially associated with reduction of sperm quality and reproductive output. Hypoxia events are able to interact with gonad steroidogenesis by acting on the steroids precursor cholesterol availability or directly on aromatase action, with an impact on the quality of gametes and reproductive success. Climate change related effects on water parameters likely influence also the reproductive behavior of fish. Although the precise mechanisms underlying the regulation of these effects are not always understood, in this review we discuss different hypothesis and propose future research perspectives.


Assuntos
Encéfalo/fisiologia , Mudança Climática , Peixes/fisiologia , Gônadas/fisiologia , Hipófise/fisiologia , Reprodução/fisiologia , Animais , Gônadas/efeitos dos fármacos
17.
J Toxicol Environ Health A ; 83(3): 95-112, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32075523

RESUMO

Bisphenol A (BPA) is an emerging pollutant of global concern. Viviparous fish Goodea atripinnis is endemic to the Central Mexican Plateau where BPA was detected; however, few studies examined the influence of this chemical on native viviparous fish. The effects of BPA (sublethal dose) were determined on DNA integrity and Foxl2 expression in G. atripinnis gonads, and interactions of BPA with FOXL2 protein. Genotoxicity analysis revealed that % comets, at 14 and 28 days and comet tail length (at 14 days) were significantly higher in exposed compared to controls. In general, the % DNA tail was not markedly higher in BPA-treated fish; however, tail moment related to tail length exhibited significant increases in DNA damage. RT-qPCR assays showed Foxl2 overexpression after 14 and 28 days of exposure in females; while in males, Foxl2 was overexpressed after 28 days. In silico analysis demonstrated that BPA interacted with seven residues located in FOXL2 homeodomain. In summary, sublethal BPA doses induced DNA damage and changes in Foxl2 expression in gonadal cells of G. atripinnis, which may adversely affect reproduction in BPA-exposed wild populations. Foxl2 overexpression and BPA-FOXL2 interaction suggested alterations in processes involving Foxl2. Viviparous fish may thus serve as potential non-conventional models for assessing pollutants effects.


Assuntos
Compostos Benzidrílicos/toxicidade , Ciprinodontiformes , Proteína Forkhead Box L2/metabolismo , Gônadas/efeitos dos fármacos , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Feminino , Proteína Forkhead Box L2/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino
18.
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
19.
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
20.
Environ Pollut ; 260: 113980, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31991354

RESUMO

Developmental exposures to estrogenic chemicals possibly cause structural and functional abnormalities of reproductive organs in vertebrates. Bisphenol AF (BPAF), a bisphenol A (BPA) analogue, has been shown to have higher estrogenic activity than BPA, but little is known about the effects of BPAF on gonadal development, particularly gonadal differentiation. We aimed to determine whether low concentrations of BPAF could disrupt gonadal differentiation and subsequent development using Xenopus laevis, a model species for studying feminizing effects of estrogenic chemicals. X. laevis tadpoles were exposed to BPAF (1, 10, 100 nM) or 17ß-estradiol (E2, positive control) from stages 45/46 to 53 and 66 in a semi-static exposure system, with a prolonged treatment with the highest concentration to the eighth week post-metamorphosis (WPM8). Gonadal morphology and histology as well as sexually dimorphic gene expression were examined to evaluate the effects of BPAF. All concentrations of BPAF caused changes in testicular morphology at different developmental stages compared with controls. Specifically, at stage 53, BPAF like E2 resulted in decreases in both the size and the number of gonadal metameres (gonomeres) in testes, looking like ovaries. Some of BPAF-treated testes remained segmented and even became discontinuous and fragmented at subsequent stages. Histological abnormalities were also observed in BPAF-treated testes, such as ovarian cavity at stages 53 and 66 and poorly developed seminiferous tubules on WPM8. At the molecular level, BPAF inhibited expression of male highly expressed genes in testes at stage 53. Correspondingly, BPAF, like E2, inhibited cell proliferation in testes at stage 50. All results show that low concentrations of BPAF inhibited testicular differentiation and subsequent development in X. laevis, along with feminizing effects to some degree. Our finding implies a risk of BPAF to the male reproductive system of vertebrates including humans.


Assuntos
Compostos Benzidrílicos/toxicidade , Poluentes Ambientais/toxicidade , Gônadas/crescimento & desenvolvimento , Animais , Diferenciação Celular , Feminino , Feminização , Gônadas/efeitos dos fármacos , Humanos , Masculino , Fenóis , Testículo , Xenopus laevis
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