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1.
Ecotoxicol Environ Saf ; 209: 111845, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385677

RESUMO

The coexistence of nanoparticles and organic toxicants in the environment modifies pollutant bioavailability and toxicity. This study investigated the influence of silicon dioxide nanoparticles (n-SiO2) on the uptake of tetrabromobisphenol A (TBBPA) and its impact on the thyroid endocrine system in zebrafish larvae. Zebrafish (Danio rerio) embryos were exposed to TBBPA at different concentrations (50, 100, and 200 µg/L) alone or in combination with n-SiO2 (25 mg/L) until 120 h post-fertilization (hpf). Chemical measurements showed that both TBBPA and n-SiO2 were bioconcentrated in zebrafish larvae, and the uptake of TBBPA was enhanced by n-SiO2. Furthermore, zebrafish larvae exposed to 200 µg/L TBBPA alone exhibited significantly increased T4 contents and decreased T3 contents, whereas n-SiO2 treatment alone did not have a detectable effect. Furthermore, the thyroid hormone levels changed more upon treatment with 200 µg/L TBBPA combined with 25 mg/L n-SiO2 than upon TBBPA treatment alone. Alterations in gene transcription along the related hypothalamic-pituitary-thyroid (HPT) axis were observed, and expression of the binding and transport protein transthyretin (TTR) was significantly decreased for both TBBPA alone and co-exposure with n-SiO2. Thus, the current study demonstrates that n-SiO2, even at the nontoxic concentrations, increases thyroid hormone disruption in zebrafish larvae co-exposed to TBBPA by promoting its bioaccumulation and bioavailability.


Assuntos
Nanopartículas/toxicidade , Bifenil Polibromatos/metabolismo , Dióxido de Silício/toxicidade , Poluentes Químicos da Água/metabolismo , Animais , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/metabolismo , Larva/efeitos dos fármacos , Bifenil Polibromatos/toxicidade , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia
2.
Int J Mol Sci ; 22(2)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33477789

RESUMO

Endocrine disrupting chemicals (EDCs) are exogenous chemicals which can disrupt any action of the endocrine system, and are an important class of substances which play a role in the Developmental Origins of Health and Disease (DOHaD) [...].


Assuntos
Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Exposição Ambiental/prevenção & controle , Humanos
3.
Ecotoxicol Environ Saf ; 208: 111570, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396099

RESUMO

Traditional brominated flame retardants (BFRs) negatively affect the environment and human health, especially in the sensitive (developing) nervous system. Considering the physicochemical similarities between novel brominated flame retardants (NBFRs) and BFRs, more and more evidence reveals the neurotoxic effects of NBFRs. We reviewed the neuro(endocrine) toxic effects of NBFRs in vivo and in vitro and discussed their action mechanisms based on the available information. The neurotoxic potential of NBFRs has been demonstrated through direct neurotoxicity and disruption of the neuroendocrine system, with adverse effects on neurobehavioral and reproductive development. Mechanistic studies have shown that the impact of NBFRs is related to the complex interaction of neural and endocrine signals. From disrupting the gender differentiation of the brain, altering serum thyroid/sex hormone levels, gene/protein expression, and so on, to interfere with the feedback effect between different levels of the HPG/HPT axis. In this paper, the mechanism of neurotoxic effects of NBFRs is explored from a new perspective-neuro and endocrine interactions. Gaps in the toxicity data of NBFRs in the neuroendocrine system are supplemented and provide a broader dataset for a complete risk assessment.


Assuntos
Sistema Endócrino/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Retardadores de Chama/toxicidade , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Hidrocarbonetos Bromados/análise , Síndromes Neurotóxicas/metabolismo , Medição de Risco , Hormônios Tireóideos
4.
Ecotoxicol Environ Saf ; 208: 111617, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396137

RESUMO

Nitrate (NO3-), a potential toxic nitrogenous compound to aquatic animals, is distributed in aquatic ecosystems worldwide. The aim of this study was to investigate the effects of different NO3- levels on growth performance, health status, and endocrine function of juvenile turbot (Scophthalmus maximus) in recirculating aquaculture systems (RAS). Fish were exposed to 0 mg/L (control, CK), 50 mg/L (low nitrate, LN), 200 mg/L (medium nitrate, MN), and 400 mg/L (high nitrate, HN) NO3-N for 60 d in experimental RAS. Cumulative survival (CS) was significantly decreased with increasing NO3- levels in LN, MN, and HN. The lowest CS was 35% in the HN group. Growth parameters, including absolute growth rate, specific growth rate, and feed conversion rate, were significantly different in HN compared with that in the CK. Histological survey of gills and liver revealed dose-dependent histopathological damage induced by NO3- exposure and significant differences in glutamate pyruvate transaminase and glutamate oxalate transaminase in MN and HN compared with that in the CK. The hepatosomatic index in HN was significantly higher than that in the CK. Additionally, NO3- significantly increased bioaccumulation in plasma in LN, MN, and HN compared to that in the CK. Significant decreases in hemoglobin and increases in methemoglobin levels indicated reduced oxygen-carrying capacity in HN. Additionally, qRT-PCR and enzyme-linked immunosorbent assay (ELISA) were developed to investigate key biomarkers involved in the GH/IGF-1, HPT, and HPI axes. Compared with that in the CK, the abundance of GH, GHRb, and IGF-1 was significantly lower in HN, whereas GHRa did not differ between treatments. The plasma T3 level significantly decreased in LN, MN, and HN and T4 significantly decreased in HN. The CRH, ACTH, and plasma cortisol levels were significantly upregulated in HN compared with that in the CK. We conclude that elevated NO3- exposure leads to growth retardation, impaired health status, and endocrine disorders in turbot and the NO3- level for juvenile turbot culture should not exceed 50 mg/L NO3-N in RAS. Our findings indicate that endocrine dysfunction of the GH/IGF-1, HPT, and HPI axes might be responsible for growth inhibition induced by NO3- exposure.


Assuntos
Aquicultura/métodos , Sistema Endócrino/efeitos dos fármacos , Linguados/crescimento & desenvolvimento , Nitratos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Sistema Endócrino/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/patologia , Nível de Saúde , Fígado/efeitos dos fármacos , Fígado/patologia , Alimentos Marinhos , Hormônios Tireóideos/metabolismo
5.
Rev Med Suisse ; 17(720-1): 24-28, 2021 Jan 13.
Artigo em Francês | MEDLINE | ID: mdl-33443826

RESUMO

Health care of gender-incongruent persons deserves optimization. The new World Health Organization ICD-11, introduced this year, classifies gender-incongruence to « conditions related to sexual health ¼, and not anymore to « mental and behavioral disorders ¼. From an endocrine perspective, gender-affirming hormonal treatment induces physical changes consistent with gender identity, but good-quality, long follow-up studies concerning efficacy and safety are needed. Improvements in training of medical professionals as well as a specialized multidisciplinary approach are important measures to be taken.


Assuntos
Sistema Endócrino/efeitos dos fármacos , Disforia de Gênero/fisiopatologia , Disforia de Gênero/terapia , Saúde Sexual , Pessoas Transgênero , Feminino , Disforia de Gênero/classificação , Disforia de Gênero/psicologia , Identidade de Gênero , Humanos , Classificação Internacional de Doenças , Masculino , Pessoas Transgênero/psicologia , Organização Mundial da Saúde
6.
Chemosphere ; 260: 127565, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32758781

RESUMO

The effects of fluoride on endocrine tissues has not been sufficiently explored to date. The current body of knowledge suggest significant effects of that mineral on reducing sex hormone levels, which may consequently impair fertility and disrupt puberty. The majority of studies confirm that sodium fluoride increases TSH levels and decreases the concentrations of T3 and T4 produced by the thyroid. Moreover, a correlation was observed between NaF and increased secretion of PTH by the parathyroid glands, without a significant impact on body calcium levels. Probably, fluoride may exert adverse effects on insulin levels, impairing pancreatic function and resulting in abnormal glucose tolerance. Observations also include decreased levels of cortisol secreted by the adrenal glands. In light of the few existing studies, the mechanism of fluoride toxicity on the endocrine system has been described.


Assuntos
Sistema Endócrino/efeitos dos fármacos , Fluoretos/farmacologia , Glândulas Suprarrenais/metabolismo , Animais , Fluoretos/efeitos adversos , Fluoretos/toxicidade , Humanos , Hidrocortisona/metabolismo , Insulina/análise , Glândulas Paratireoides/efeitos dos fármacos , Glândulas Paratireoides/metabolismo , Fluoreto de Sódio/farmacologia , Fluoreto de Sódio/toxicidade , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo
7.
Ecotoxicol Environ Saf ; 201: 110820, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531574

RESUMO

Growth hormone (GH)/insulin-like growth factor (IGF) axis plays a critical role in fetal development. However, the effect of arsenite exposure on the GH/IGF axis and its toxic mechanism are still unclear. Zebrafish embryos were exposed to a range of NaAsO2 concentrations (0.0-10.0 mM) between 4 and 120 h post-fertilization (hpf). Development indexes of survival, malformation, hatching rate, heart rate, body length and locomotor behavior were measured. Hormone levels, GH/IGF axis-related genes, and nerve-related genes were also tested. The results showed that survival rate, hatching rate, heart rate, body length and locomotor behavior all decreased, while deformity increased. At 120 hpf, the survival rate of zebrafish in 1.5 mM NaAsO2 group was about 70%, the deformity rate exceeded 20%, and the body length shortened to 3.35 mm, the movement distance of zebrafish decreased approximately 63.6% under light condition and about 52.4% under dark condition. The level of GH increased and those of IGF did not change significantly, while the expression of GH/IGF axis related genes (ghra, ghrb, igf2r, igfbp3, igfbp2a, igfbp5b) and nerve related genes (dlx2, shha, ngn1, elavl3, gfap) decreased. In 1.5 mM NaAsO2 group, the decrease of igfbp3 and igfbp5b was almost obvious, about 78.2% and 72.2%. The expression of nerve genes in 1.5 mM NaAsO2 group all have declined by more than 50%. These findings suggested that arsenite exerted disruptive effects on the endocrine system by interfering with the GH/IGF axis, leading to zebrafish embryonic developmental toxicity.


Assuntos
Arsenitos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Hormônio do Crescimento/metabolismo , Somatomedinas/metabolismo , Peixe-Zebra , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/embriologia , Sistema Endócrino/metabolismo , Hormônio do Crescimento/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Transdução de Sinais , Somatomedinas/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
8.
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
10.
Chem Biol Interact ; 326: 109099, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370863

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Disruptores Endócrinos/efeitos adversos , Sistema Endócrino/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Animais , Humanos
11.
Zhongguo Zhong Yao Za Zhi ; 45(5): 997-1003, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237438

RESUMO

To investigate the characteristics of the cold and heat properties of each resolution component of Açaí and the material basis of cooling by observing the effect of resolution components, such as Açaí oil, alcohol extract and water extract, on the neurotransmitter, endocrine hormone and immune factor level in mice with deficiency-heat and deficiency-cold syndrome. KM male mice were randomly divided into 12 groups, namely blank group, deficiency-heat model group, deficiency-heat+Açaí group, deficiency-heat+Açaí oil group, deficiency-heat+Açaí alcohol extract group, deficiency-heat+Açaí water extract group, deficiency-cold model group, deficiency-cold+Cinnamomi Cortex group, deficiency-cold+Açaí group, deficiency-cold+Açaí oil group, deficiency-cold+Açaí alcohol extract group, and deficiency-cold+Açaí water extract group. The mice in deficiency-heat group were given with thyroid tablet solution(160 mg·kg~(-1)), and the mice in deficiency-cold group were given with hydrocortisone solution(25 mg·kg~(-1)) by intragastric administration every afternoon for 14 days. The mice in each administration group received corresponding drug. The neurotransmitter, endocrine hormone and immune factor levels in the mice were measured after the experiment. The Açaí alcohol extract, consistent with the Açaí powder, showed a regulatory effect on the deficiency-heat model mice; Açaí oil and its water extract were consistent with Cinna-momi Cortex, showing a regulatory effect on the deficiency-cold model mice. In this study, on the basis of proving that Açaí was was cool in property, it also revealed that alcohol extract of Açaí was cool while oil and water extract were warm in property based on the effect of Açaí on neuro-endocrine-immune network. The results suggested that the medicine property of Açaí was the result of the comprehensive action of the resolution components with different properties, and the alcohol extract of Açaí was proved as the material basis of Açaí cold medicine by using the methods of homogeneous comparison and heterogeneous disproval.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Sistema Endócrino/efeitos dos fármacos , Euterpe/química , Sistema Imunitário/efeitos dos fármacos , Sistema Nervoso/efeitos dos fármacos , Animais , Hormônios/metabolismo , Fatores Imunológicos/metabolismo , Masculino , Camundongos , Neurotransmissores/metabolismo , Extratos Vegetais/farmacologia
12.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1004-1010, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237439

RESUMO

The aim of this paper was to study the effect of Lepidium meyenii(Maca) on cyclic nucleotides, neurotransmitter levels and hypothalamic-pituitary-adrenal axis and immunization of deficiency-cold and deficiency-heat syndrome rats, in order to explore the cold and hot medicinal properties of Maca. SD rats were divided into blank group, deficiency-cold syndrome group, Cinnamomi Cortex of deficiency-cold syndrome(30 g·kg~(-1)) group, high and low-dose Maca groups(2.4, 1.2 g·kg~(-1)), deficiency-heat syndrome group, Phellodendri Chinensis Cortex(PCC) of deficiency-heat syndrome(5 g·kg~(-1)), and high and low-dose Maca groups(2.4, 1.2 g·kg~(-1)). The rats were treated with intramuscular injection of hydrocortisone(20 mg·kg~(-1)) or dexamethasone sodium phosphate(0.35 mg·kg~(-1)) for 21 days to set up the deficiency-cold and deficiency-heat model. The levels of cAMP, cGMP, NE, DA, 5-HT, CRH, ACTH, CORT and IgM, IgG, C3, C4 were detected by radio immunoassay. Both the high-dose Maca group and the low-dose Maca group can significantly improve the overall state and body weight of rats with deficiency-cold syndrome(P<0.01, P<0.05), significantly increasing cAMP, cAMP/cGMP, NE, DA, ACTH(P<0.01, P<0.001), and significantly decreasing 5-HT(P<0.01, P<0.001). However, high-dose and low-dose Maca groups could not improve the deficiency-heat syndrome, and the levels of cAMP, cGMP, cAMP/cGMP, NE, DA, 5-HT and ACTH were not statistically significant. Maca had a significant regulatory effect on CORT, IgM, IgG and C3 content of rats with deficiency-cold and deficiency-heat syndrome(P<0.01, P<0.05, P<0.001). Maca showed the same effect with Cinnamomi Cortex in adjusting the levels of deficiency-cold rats, but in opposition to Phellodendri Chinese Cortex. This paper confirmed that Maca was slightly warm based on its effect on cyclic nucleotide levels and neuro-endocrine-immune networks by the pharmacological experimental method.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Sistema Endócrino/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Lepidium/química , Sistema Nervoso/efeitos dos fármacos , Animais , Sistema Hipotálamo-Hipofisário , Medicina Tradicional Chinesa , Neurotransmissores , Nucleotídeos Cíclicos , Sistema Hipófise-Suprarrenal , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Temperatura
13.
Int J Mol Sci ; 21(6)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178293

RESUMO

Anthropogenic contaminants in water can impose risks to reproductive health. Most of these compounds are known to be endocrine disrupting chemicals (EDCs). EDCs can impact the endocrine system and subsequently impair the development and fertility of non-human animals and humans. The source of chemical contamination in water is diverse, originating from byproducts formed during water disinfection processes, release from industry and livestock activity, or therapeutic drugs released into sewage. This review discusses the occurrence of EDCs in water such as disinfection byproducts, fluorinated compounds, bisphenol A, phthalates, pesticides, and estrogens, and it outlines their adverse reproductive effects in non-human animals and humans.


Assuntos
Disruptores Endócrinos/efeitos adversos , Sistema Endócrino/efeitos dos fármacos , Genitália/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Água/química , Animais , Poluentes Ambientais/efeitos adversos , Humanos , Poluentes Químicos da Água/efeitos adversos
14.
Environ Res ; 184: 109310, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32163770

RESUMO

The pesticide flutolanil has been detected in fish and aquatic environments, but its potential impact on the endocrine function is unknown. In this study, two-month zebrafish were exposed to the environmentally relevant concentrations of flutolanil for 60 days to examine the reproductive endpoints on the gonad endocrine system. Increased 17 beta-estradiol (17ß-E2) content and 17ß-E2/T ratio and decreased testosterone (T) in male suggested that flutolanil produces the estrogenic effect. In support of this view, vitellogene (vtg1, vtg2) and cytochrome P450 aromatase 19a (cyp19a) expression were up-regulated in the male liver. The levels of global DNA methylation were increased in ovary. Parental zebrafish exposure to different concentrations of flutolanil affected the offspring development as shown by short body length, and increased mortality. Thus, these results demonstrate that flutolanil exposure results in gonad endocrine disruption, decreased reproduction, and developmental toxicity in F1, highlighting the importance of assessing the potential environmental risks of flutolanil application.


Assuntos
Anilidas , Disruptores Endócrinos , Poluentes Químicos da Água , Anilidas/toxicidade , Animais , Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Feminino , Masculino , Reprodução/efeitos dos fármacos , Vitelogeninas , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
15.
Chemosphere ; 249: 126536, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32217413

RESUMO

This study investigated the influences of titanium dioxide nanoparticles (n-TiO2) on the thyroid endocrine disruption and neurobehavioral defects induced by pentachlorophenol (PCP) in zebrafish (Danio rerio). Embryos (2 h post-fertilization) were exposed to PCP (0, 3, 10, and 30 µg/L) or in combination with n-TiO2 (0.1 mg/L) until 6 days post-fertilization. The results showed that n-TiO2 alone did not affect thyroid hormones levels or transcriptions of related genes. Exposure to PCP significantly decreased thyroid hormone thyroxine (T4) content, thyroid stimulating hormone (TSH) level and transcription of thyroglobulin (tg), but significantly increased 3,5,3'-triiodothyronine (T3) level and upregulation of deiodinase 2 (dio2). In comparison, the co-exposure with n-TiO2 significantly reduced the content of T3 by depressing the potential targets, tg and dio2. For neurotoxicity, the single and co-exposure resulted in similar effects with significant downregulation of neurodevelopment-related genes (ELAV like RNA Binding Protein 3, elavl3; Growth associated protein-43, gap43; α-tubulin) and inhibited locomotor activity. The results indicated that the presence of n-TiO2 significantly enhanced the PCP-induced thyroid endocrine disruption but not the neurobehavioral defects in zebrafish larvae.


Assuntos
Disruptores Endócrinos/toxicidade , Pentaclorofenol/toxicidade , Peixe-Zebra/fisiologia , Animais , Sistema Endócrino/efeitos dos fármacos , Larva/efeitos dos fármacos , Nanopartículas/toxicidade , Pentaclorofenol/metabolismo , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Titânio/toxicidade , Tri-Iodotironina/metabolismo , Peixe-Zebra/metabolismo
16.
Ecotoxicol Environ Saf ; 195: 110496, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32213369

RESUMO

The impact of progestins (i.e. synthetic forms of progesterone) on aquatic organisms has drawn increasing attention due to their widespread occurrence in the aquatic environments and potential effects on the endocrine system of fish. In this study, the effects of norethindrone (NET, a progestin) on the reproductive behavior, sex hormone production and transcriptional expressions were evaluated by exposing female zebrafish to NET at 0, 3.1, 36.2 and 398.6 ng L-1 for 60 days. Results showed that NET impaired the mating behaviors of female at 36.2 and 398.6 ng L-1 exhibited by males and increased the frequency of atretic follicular cells in the ovary exposed to NET at 398.6 ng L-1. As for sex hormones, plasma testosterone concentration in zebrafish increased, while estradiol concentration decreased. Up-regulation of genes (Npr, Mpra, Mprß, Fshß, Lß, Tshb, Nis and Dio2) was detected in the brain of fish exposed to NET at 398.6 ng L-1. The transcriptional levels of genes (Esr1, Vtg1, Ar, Cyp19a, Cyp11b and Ptgs2) were generally inhibited in the ovary of zebrafish by NET at 398.6 ng L-1. Moreover, the transcripts of genes (Vtg1, Esr1, Ar and Pgr) in the liver were reduced by NET at 36.2 and 398.6 ng L-1. Our findings suggest that NET can potentially diminish the of fish populations not only by damaging their reproductive organs, but also by altering their mating behavior through the changes in the expressions of genes responsible for the production of sex hormones.


Assuntos
Hormônios Esteroides Gonadais/sangue , Noretindrona/toxicidade , Ovário/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Sistema Endócrino/efeitos dos fármacos , Feminino , Hormônios Esteroides Gonadais/genética , Masculino , Ovário/patologia , Progesterona/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
17.
J Ovarian Res ; 13(1): 32, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32197626

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex reproduction and endocrine disorder of women in the reproductive age. Spearmint (Mentha spicata L.) has anti-androgenic activity and flaxseed (Linum usitatissimum L.) contains phytoestrogen and was reported to improve PCOS conditions. This study aimed to evaluate PCOS conditions following administration of a mixture of these two plants. METHODS: Twenty-four rats with regular cycles were randomly divided into four groups as control (C) and treatment-control (TC) received a combination of spearmint extract (SE) + flaxseed extract (FE). PCOS was induced in PCOS and treatment (T) groups by a single intramuscular injection of estradiol valerate. The treatment group received a combination of SE and FE for 30 days, 7 weeks after injection of estradiol valerate. Estrous cycles were monitored for 10 days and in the last day animals were sacrificed, ovaries were collected for the histomorphometric study and the serum levels of progesterone, testosterone, estradiol, and dehydroepiandrosterone (DHEA) were measured. RESULT: Significant rise in progesterone and a decrease in testosterone and estradiol with no significant change of DHEA in the T group, was observed in comparison with the PCOS group (P < 0.05). No significant difference noticed between T and control groups (C &CT) regarding evaluated hormones. A significant increase in primary, pre-antral and antral follicles noticed in the T group compared to the PCOS group. The number of cystic follicles decreased in the T group compared with the PCOS group. Granulosa layer thickness increased while the thickness of theca decreased significantly in the T group compared to the PCOS group (P < 0.05). No significant endocrine or histological differences noticed between C and TC groups. CONCLUSION: A combination of flaxseed and spearmint extract improved the endocrine profile and the histomorphometric features of the ovary in the T group compared to the PCOS group.


Assuntos
Sistema Endócrino/efeitos dos fármacos , Linho/química , Mentha spicata/química , Ovário/metabolismo , Ovário/patologia , Extratos Vegetais/farmacologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Animais , Biomarcadores , Biópsia , Modelos Animais de Doenças , Sinergismo Farmacológico , Ciclo Estral/efeitos dos fármacos , Feminino , Hormônios/sangue , Hormônios/metabolismo , Imuno-Histoquímica , Extratos Vegetais/química , Síndrome do Ovário Policístico/tratamento farmacológico , Ratos
18.
Environ Int ; 137: 105470, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32050122

RESUMO

High-throughput and computational tools provide a new opportunity to calculate combined bioactivity of exposure to diverse chemicals acting through a common mechanism. We used high throughput in vitro bioactivity data and exposure predictions from the U.S. EPA's Toxicity and Exposure Forecaster (ToxCast and ExpoCast) to estimate combined estrogen receptor (ER) agonist activity of non-pharmaceutical chemical exposures for the general U.S. population. High-throughput toxicokinetic (HTTK) data provide conversion factors that relate bioactive concentrations measured in vitro (µM), to predicted population geometric mean exposure rates (mg/kg/day). These data were available for 22 chemicals with ER agonist activity and were estimated for other ER bioactive chemicals based on the geometric mean of HTTK values across chemicals. For each chemical, ER bioactivity across ToxCast assays was compared to predicted population geometric mean exposure at different levels of in vitro potency and model certainty. Dose additivity was assumed in calculating a Combined Exposure-Bioactivity Index (CEBI), the sum of exposure/bioactivity ratios. Combined estrogen bioactivity was also calculated in terms of the percent maximum bioactivity of chemical mixtures in human plasma using a concentration-addition model. Estimated CEBIs vary greatly depending on assumptions used for exposure and bioactivity. In general, CEBI values were <1 when using median of the estimated general population chemical intake rates, while CEBI were ≥1 when using the upper 95th confidence bound for those same intake rates for all chemicals. Concentration-addition model predictions of mixture bioactivity yield comparable results. Based on current in vitro bioactivity data, HTTK methods, and exposure models, combined exposure scenarios sufficient to influence estrogen bioactivity in the general population cannot be ruled out. Future improvements in screening methods and computational models could reduce uncertainty and better inform the potential combined effects of estrogenic chemicals.


Assuntos
Disruptores Endócrinos , Sistema Endócrino , Poluentes Ambientais , Ensaios de Triagem em Larga Escala , Bioensaio , Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Estrogênios , Humanos
19.
Environ Int ; 137: 105552, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32059144

RESUMO

Swine farm wastewaters (SFWs) are generally discharged either directly into nearby rivers or into fish ponds as a source of fertilizer/food for aquaculture in China. SFWs contain various contaminants including steroid hormones. However, there is an extreme paucity of data on their effects in fish populations. Here we investigated the endocrine disrupting effects of SFWs in G. affinis from 2 rivers (7 sites) and 2 fish ponds (2 sites) receiving SFWs and a reference site in Guangdong Province, China. In this study, a total number of 3078 adult western mosquitofish (Gambusia affinis) were collected and the sex ratio was determined. In addition, secondary sexual characteristics were examined and the transcriptional levels of target genes were analyzed. The results showed the mosquitofish populations had a significant increase in male-to-female ratio from 7 sites (including 2 fish ponds) among the 9 sampling sites. The hemal spines of females were masculinized at most sites while the hemal spines of males were feminized at approximately half of the sites (including 2 fish ponds). Significant reduction in vitellogenin (Vtg) mRNA expression was observed in females from 2 sites (including RS7) while elevated Vtg mRNA expression was noticed in males from 2 sites along the rivers (including RS7). Redundancy analysis showed that androgens in the water samples were closely related with male-to-female ratio in the mosquitofish populations and the masculinized hemal spines of females. The findings from this study demonstrated that discharge of SFWs could result in occurrence of both masculinized females and feminized males in mosquitofish population.


Assuntos
Ciprinodontiformes , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Águas Residuárias , Poluentes Químicos da Água , Animais , China , Ecossistema , Sistema Endócrino/efeitos dos fármacos , Feminino , Masculino , Suínos , Poluentes Químicos da Água/toxicidade
20.
Environ Toxicol Chem ; 39(4): 739-753, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32030793

RESUMO

Recent regulatory testing programs have been designed to evaluate whether a chemical has the potential to interact with the endocrine system and could cause adverse effects. Some endocrine pathways are highly conserved among vertebrates, providing a potential to extrapolate data generated for one vertebrate taxonomic group to others (i.e., biological read-across). To assess the potential for biological read-across, we reviewed tools and approaches that support species extrapolation for fish, amphibians, birds, and reptiles. For each of the estrogen, androgen, thyroid, and steroidogenesis (EATS) pathways, we considered the pathway conservation across species and the responses of endocrine-sensitive endpoints. The available data show a high degree of confidence in the conservation of the hypothalamus-pituitary-gonadal axis between fish and mammals and the hypothalamus-pituitary-thyroid axis between amphibians and mammals. Comparatively, there is less empirical evidence for the conservation of other EATS pathways between other taxonomic groups, but this may be due to limited data. Although more information on sensitive pathways and endpoints would be useful, current developments in the use of molecular target sequencing similarity tools and thoughtful application of the adverse outcome pathway concept show promise for further advancement of read-across approaches for testing EATS pathways in vertebrate ecological receptors. Environ Toxicol Chem 2020;39:739-753. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Ecotoxicologia/métodos , Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Modelos Biológicos , Vertebrados/metabolismo , Rotas de Resultados Adversos , Animais , Ecotoxicologia/legislação & jurisprudência , Disruptores Endócrinos/sangue , Disruptores Endócrinos/farmacocinética , Sistema Endócrino/metabolismo , Regulamentação Governamental , Ligantes , Ligação Proteica , Medição de Risco , Especificidade da Espécie , Vertebrados/sangue
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