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1.
Pestic Biochem Physiol ; 174: 104802, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33838703

RESUMO

The beet armyworm, Spodoptera exigua, is a highly polyphagous pest originated from Southeast Asia but has spread globally, attacking economically important crops and fruits. Bistrifluron insecticide is one of the highly active insect growth regulators that has been reported to inhibit development and longevity in other lepidopteran species and could be used in the control of S. exigua. In the present study, the age-stage, two-sex life table technique was applied to assess the sublethal effects of bistrifluron on biological traits and vitellogenin gene (SeVg) expression when 2nd instar larvae fed to sublethal concentrations (LC10, LC20 and LC40) of bistrifluron. Mean generation time from eggs to adults was longer at LC40 (37.79 ± 0.81 d) and LC20 (37.04 ± 0.72) compared to the LC10 (36.89 ± 0.63 d) and control groups (36.07 ± 0.38 d). Fecundity of female at LC40 (279.17 ± 42.8 eggs), LC20 (347 ± 35.4 eggs) and LC10 (411.58 ± 42.38 eggs) were significantly lower than the control treatment (532.47 ± 7.13). Furthermore, the lower intrinsic rates of increase (LC40; r = 0.1207 ± 0.009, LC20; r = 0.1329 ± 0.009 and LC10; r = 0.14398 ± 0.009 compared to the control r = 0.164 ± 0.0076), was observed along with significantly extended mean generation times (LC40; T = 34.825 ± 0.317 days, LC20; T = 33.27 ± 0.368 days and LC10; T = 31.899 ± 0.398 days compared to the control 30.927 ± 0.255 days). Furthermore, the contents of energy reserve macronutrients (carbohydrate, lipid and protein) significantly reduced in dose and time dependent manner in treated insects as compared to control. Furthermore, the expression level of SeVg mRNA significantly decreased by 43.8% in the female adults when one-day-old second instar larvae were treated with sublethal concentrations of bistrifluron in comparison with the control. Documenting these sublethal effects is a vital, and often overlooked factor, in assessing the overall efficacy of insecticides in the management of pest populations.


Assuntos
Inseticidas , Vitelogeninas , Animais , Feminino , Hidrocarbonetos Halogenados , Inseticidas/toxicidade , Larva , Nutrientes , Compostos de Fenilureia , Spodoptera/genética , Vitelogeninas/genética
2.
Arch Insect Biochem Physiol ; 106(3): e21775, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33644918

RESUMO

DDX3 represents a well-defined subfamily of DEAD-box RNA helicase and exerts multiple functions in RNA metabolism, cell cycle, tumorigenesis, signal pathway, and fertility. Our previous study has shown that LmDDX3, the ortholog of DDX3 in Locusta migratoria, is ubiquitously expressed, and with a high abundance in testis and ovary. Knockdown of LmDDX3 results in a lethal phenotype in nymph, but it still remains unclear for its role in reproductive process. In this study, we therefore characterized LmDDX3 expression in female adult locust and analyzed its function in oocyte development. LmDDX3 was expressed in all tissues examined with significant more transcripts in ovary and hindgut. In ovary, a strong expression level was detected at the day just after adult eclosion, and a dramatic reduction then occurred during the oocyte development. LmDDX3 RNAi led to a reduced vitellogenin (Vg) expression in fat body via partially at least, the JH signaling pathway, and caused an upregulation of vitellogenin receptor (VgR) in ovary, and thus blocked the ovarian development and oocyte maturation. Sequence and phylogenetic analysis indicated that LmDDX3 was closely related to termite DDX3. Taken together, these data reveal a critical role for LmDDX3 in regulating the transcription of Vg and VgR, two major factors in vitellogenesis that is a key process required for ovary development and oocyte maturation in locust, and contribute thereof a new putative target for locust biological control.


Assuntos
Locusta migratoria , Oócitos/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , RNA Helicases , Animais , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Feminino , Expressão Gênica , Genes de Insetos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Locusta migratoria/genética , Locusta migratoria/fisiologia , Ninfa/genética , Ninfa/fisiologia , Oogênese/fisiologia , Ovário/metabolismo , Filogenia , RNA Helicases/genética , RNA Helicases/metabolismo , Interferência de RNA , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Vitelogênese/fisiologia , Vitelogeninas/genética , Vitelogeninas/metabolismo
3.
Environ Sci Technol ; 55(8): 5024-5036, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33755441

RESUMO

There is increasing pressure to develop alternative ecotoxicological risk assessment approaches that do not rely on expensive, time-consuming, and ethically questionable live animal testing. This study aimed to develop a comprehensive early life stage toxicity pathway model for the exposure of fish to estrogenic chemicals that is rooted in mechanistic toxicology. Embryo-larval fathead minnows (FHM; Pimephales promelas) were exposed to graded concentrations of 17α-ethinylestradiol (water control, 0.01% DMSO, 4, 20, and 100 ng/L) for 32 days. Fish were assessed for transcriptomic and proteomic responses at 4 days post-hatch (dph), and for histological and apical end points at 28 dph. Molecular analyses revealed core responses that were indicative of observed apical outcomes, including biological processes resulting in overproduction of vitellogenin and impairment of visual development. Histological observations indicated accumulation of proteinaceous fluid in liver and kidney tissues, energy depletion, and delayed or suppressed gonad development. Additionally, fish in the 100 ng/L treatment group were smaller than controls. Integration of omics data improved the interpretation of perturbations in early life stage FHM, providing evidence of conservation of toxicity pathways across levels of biological organization. Overall, the mechanism-based embryo-larval FHM model showed promise as a replacement for standard adult live animal tests.


Assuntos
Cyprinidae , Poluentes Químicos da Água , Animais , Etinilestradiol/toxicidade , Proteômica , Diferenciação Sexual , Vitelogeninas , Poluentes Químicos da Água/toxicidade
4.
Aquat Toxicol ; 233: 105788, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33662878

RESUMO

The gene expression response thought to underlie the negative apical effects resulting from estrogen exposure have been thoroughly described in fish. Although epigenetics are believed to play a critical role translating environmental exposures into the development of adverse apical effects, they remain poorly characterized in fish species. This study investigated alterations of DNA methylation of estrogen receptor alpha (esr1) in brain and liver tissues from 8 to 10 month old male fathead minnows (Pimephales promelas) after a 2d exposure to either 2.5 ng/L or 10 ng/L 17α-ethynylestradiol (EE2). Changes in the patterns of methylation were evaluated using targeted deep sequencing of bisulfite treated DNA in the 5' region of esr1. Methylation and gene expression were assessed at 2d of exposure and after a 7 and 14d depuration period. After 2d EE2 exposure, males exhibited significant demethylation in the 5' upstream region of esr1 in liver tissue, which was inversely correlated to gene expression. This methylation pattern reflected what was seen in females. No gene body methylation (GBM) was observed for liver of exposed males. Differential methylation was observed for a single upstream CpG site in the liver after the 14d depuration. A less pronounced methylation response was observed in the upstream region in brain tissue, however, several CpGs were necessarily excluded from the analysis. In contrast to the liver, a significant GBM response was observed across the entire gene body, which was sustained until at least 7d post-exposure. No differential expression was observed in the brain, limiting functional interpretation of methylation changes. The identification of EE2-dependent changes in methylation levels strongly suggests the importance of epigenetic mechanisms as a mediator of the organismal response to environmental exposures and the need for further characterization of the epigenome. Further, differential methylation following depuration indicates estrogenic effects persist well after the active exposure, which has implications for the risk posed by repeated exposures..


Assuntos
Cyprinidae/metabolismo , Metilação de DNA/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Etinilestradiol/toxicidade , Expressão Gênica/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cyprinidae/genética , Estrogênios/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Vitelogeninas/metabolismo
5.
mBio ; 12(1)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563820

RESUMO

Many insects are intimately associated with microbial symbionts, which are passed to developing oocytes in the maternal body for ensuring vertical transmission to the next generation. Previous studies uncovered that some symbionts utilize preexisting host's molecular and cellular machineries for targeting oocytes. For example, the major yolk protein vitellogenin (Vg) is massively produced in fat body cells, processed and transported to ovaries, and incorporated into developing oocytes via Vg receptor (VgR)-mediated endocytosis, and some symbiotic bacteria were reported to interact with Vg and migrate to oocytes by hitchhiking the VgR-mediated endocytotic mechanism. In a recent study, Mao et al. (mBio 12:e01142-20, 2020, https://doi.org/10.1128/mBio.01142-20) reported that, in some leafhoppers, a considerable proportion of Vg is incorporated into symbiotic bacteria and translocated into oocytes by hitchhiking the symbiont's vertical transmission mechanism, uncovering the host's cooption of the symbiont's oocyte-targeting machineries and highlighting complicated trajectories toward host-symbiont coevolution and integration.


Assuntos
Proteínas do Ovo , Vitelogeninas , Animais , Bactérias , Oócitos , Simbiose
6.
Gene ; 774: 145423, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33434625

RESUMO

Sox9 gene, a crucial member of the Sox gene family, is present in various organisms and involved in many physiological processes, especially in sex determination and gonad development. In this study, we reported a sox9 gene (designated as Spsox9) from Scylla paramamosain through analyzing published gonad transcriptome data. Meanwhile, the accuracy was validated by PCR technology, and the 3' sequences were cloned with 3' RACE technology. The full-length cDNA of Spsox9 is 2843 bp, consisting of a 243 bp 5' UTR, an 1124 bp 3' UTR, and a 1476 bp ORF encoding 491 amino acids. Furthermore, to better understand its conservation among crustacean species, the sox9 gene ortholog was identified in several other crustaceans species with their published transcriptome data, respectively. All of the Sox9 proteins identified in the current study had the common feature of Sox proteins (HMG domain) and were highly conserved among analyzed crustacean species. In all examined tissues, the Spsox9 was mainly expressed in the gonad (testis and ovary), eyestalk, and cerebral ganglion. During embryo development, Spsox9 was highly expressed in 5 pairs of appendages, 7 pairs of appendages, and eye-pigment formation stage. During ovary development, the expression level of Spsox9 remained stable in the first 4 stages (O1-O4) and decreased in the tertiary vitellogenesis (O5) stage. During testis development, the expression level of Spsox9 was highest in the spermatid stage (T2) and was significantly different from that in the spermatocyte stage (T1) and mature sperm stage (T3) (p < 0.05). In addition, Spsox9 exhibited a sex-biased expression pattern in T1 and O1. These present results indicated that the Spsox9 gene might play crucial roles in the gonad and embryo development of mud crab.


Assuntos
Proteínas de Artrópodes/genética , Braquiúros/genética , Fatores de Transcrição SOX9/genética , Sequência de Aminoácidos , Animais , Braquiúros/embriologia , Clonagem Molecular , Sequência Conservada , DNA Complementar , Feminino , Perfilação da Expressão Gênica , Gônadas/embriologia , Humanos , Masculino , Homologia de Sequência de Aminoácidos , Caracteres Sexuais , Especificidade da Espécie , Vitelogeninas/genética
7.
Sci Total Environ ; 767: 144379, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421642

RESUMO

Equine estrogens (EEs) are widely used in hormone replacement therapy pharmaceuticals for postmenopausal women. Previous studies have shown that EEs occur in the aquatic environment; however, the potential estrogenicity and risk of EEs in aquatic organisms, including fish, have yet to be studied in detail. Therefore, we evaluated the estrogenic potential of major EEs, namely equilin (Eq), 17α-dihydroequilin (17α-Eq), 17ß-dihydroequilin (17ß-Eq), equilenin (Eqn), 17α-dihydroequilenin (17α-Eqn), and 17ß-dihydroequilenin (17ß-Eqn), on medaka (Oryzias latipes) using in vivo and in silico assays. Quantitative real-time RT-PCR analyses revealed that expression levels of choriogenin L (ChgL) and choriogenin H (ChgH) in medaka embryos responded to various types and concentrations of EEs in a concentration-dependent manner, whereas transcription levels of vitellogenin 1 were not significantly affected by any of the EEs in the concentration range tested. The order of the in vivo estrogenic potencies of EEs was as follows: 17ß-Eq > Eq > 17ß-Eqn > Eqn > 17α-Eqn > 17α-Eq. Additionally, the 50% effective concentrations (EC50) of 17ß-Eq was lower than that of 17ß-estradiol. We also investigated the interaction potential of EEs with medaka estrogen receptor (ER) subtypes in silico using a three-dimensional model of the ligand-binding domain (LBD) for each ER and docking simulations. All six EEs were found to interact with the LBDs of ERα, ERß1, and ERß2. The order of the in silico interaction potentials of EEs with each ER LBD was as follows: 17ß-Eq > 17α-Eq > Eq > 17ß-Eqn > 17α-Eqn > Eqn. Furthermore, we identified the key amino acids that interact with EEs in each ER LBD; our findings suggest that amino acids and/or their hydrogen bonding may be responsible for the ligand-specific interactions with each ER. This study is the first to comprehensively analyze the estrogenic potential of EEs in medaka both in vivo and in silico.


Assuntos
Oryzias , Animais , Simulação por Computador , Estrogênios/toxicidade , Estrona , Feminino , Cavalos , Humanos , Vitelogeninas/genética
8.
Gene ; 776: 145446, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484761

RESUMO

Bumblebees are important pollinators that have evolved between solitary and advanced eusocial insects. Compared with advanced honeybees, workers of social bumblebee species are prone to laying eggs during the competition phase, which leads to the end of the colony. Therefore, worker reproductive behavior has become a popular research topic for exploring various biological phenomena. Here, we demonstrate a novel reproduction-related function of an immune response protein-encoding gene (Immune Responsive Protein 30, IRP30) in Bombus terrestris by employing RNA interference (RNAi) and a transgenic Drosophila melanogaster system. The results show that worker egg-laying was significantly affected by IRP30 expression levels (P < 0.01). Compared with those in the dsGFP-treated groups, the first egg-laying time was delayed by 3.7 d and the egg number was decreased by 41% in the dsIRP30-treated group. In addition, the average size of the largest oocyte and the relative mRNA expression levels of Vg (vitellogenin) were significantly reduced in the dsIRP30-treated group (P < 0.05). Cellular localization by immunofluorescence demonstrated that IRP30 has important functions in the germ cells of workers' ovarioles. Overexpression of IRP30 was confirmed to increase the reproductive capability of the transgenic D. melanogaster. In conclusion, IRP30 regulates worker egg-laying by affecting the expression of Vg, the size of the ovary and the formation of the oocyte. These findings provide essential information for understanding the mechanisms underlying worker reproductive regulation.


Assuntos
Abelhas/genética , Abelhas/metabolismo , Reprodução/genética , Animais , Animais Geneticamente Modificados/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Expressão Gênica/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Ovário/metabolismo , Oviposição , Óvulo/metabolismo , Polinização , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Vitelogeninas/genética
9.
Ecotoxicol Environ Saf ; 208: 111566, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396095

RESUMO

Androgens and estrogens often co-exist in aquatic environments and pose potential risks to fish populations. However, little is known about the endocrine disrupting effects of the mixture of androgens and estrogens in fish. In this study, transcriptional level of target genes related to the hypothalamic-pituitary-gonadal-liver (HPGL) axis, sex hormone level, VTG protein concentration, histology and secondary sex characteristic were assessed in the ovaries and livers of adult female western mosquitofish (Gambusia affinis) exposed to 17ß-estradiol (E2), testosterone (T), and mixtures of E2 and T for 91 days. The results showed that the transcriptional expression of cytochrome P450, family 19, subfamily A, polypeptide 1a (Cyp19a1a) was suppressed in the 200 ng/L T treatment and the 50 ng/L E2 + 200 ng/L T treatment in the ovaries. Steroidogenic acute regulatory protein (Star) and Cyp11a1 showed a similar expression pattern in the T treatment to its corresponding T + E2 mixtures. In the ovaries, the concentrations of 17ß-estradiol and testosterone were decreased in most treatments compared with the solvent control. VTG protein was induced in all steroid treatment. However, exposure to T or E2 + T mixture did not cause the abnormal cells of the ovaries and livers and an extension of the anal fins in female G. affinis. This study demonstrates that chronic exposure to E2, T and their mixtures affects the transcripts of genes in the HPGL axis, steroid hormone level and VTG protein concentration in the ovaries and livers, but fails to cause the histopathological effect of the ovaries and livers and alter the morphology of the anal fins in G. affinis.


Assuntos
Ciprinodontiformes/fisiologia , Disruptores Endócrinos/toxicidade , Estradiol/toxicidade , Androgênios/metabolismo , Animais , Ciprinodontiformes/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Disruptores Endócrinos/metabolismo , Estradiol/metabolismo , Estrogênios/metabolismo , Feminino , Hormônios Esteroides Gonadais/metabolismo , Fígado/efeitos dos fármacos , Masculino , Ovário/efeitos dos fármacos , Testosterona/metabolismo , Vitelogeninas/metabolismo
10.
Ecotoxicol Environ Saf ; 208: 111581, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396104

RESUMO

Lead (Pb) stress affects hormone-mediated responses (e.g., reproduction) in insects. In this study, the effects of Pb stress (12.5-50 mg Pb/kg in larval artificial diets) on the reproduction of the common cutworm Spodoptera litura (Lepidoptera: Noctuidae) were investigated after 7 generations. The results showed that Pb stress did not reduce the longevity of adult females, but 50 mg Pb/kg significantly reduced the longevity of adult males, regardless of the generation. After 50 mg Pb/kg stress for one or 7 generations, the peak time of egg-laying was delayed, and egg production and hatchability were decreased significantly. The vitellin content in eggs was significantly inhibited by Pb stress. The S. litura vitellogenin (Vg) gene promoter was cloned and analyzed. Multiple putative transcription factors were predicted for the 2321 bp Vg promoter region, including the TATA box, GATA, basic helix-loop-helix (bHLH) transcription factor, Broad-Complex (BR-C) binding sites, etc. The fragment from -2222 to -211 bp of the Vg promoter was the activation domain for Vg, whereas the region from -211 to -55 bp repressed the activity of the Vg promoter. The construct promoter (-782/+76) in Trichoplusia ni (Hi5) cells significantly improved Vg expression, which was not affected by Pb stress (1 or 10 mg/ml). Therefore, Pb stress significantly inhibited the reproduction of S. litura but not by regulating the Vg promoter.


Assuntos
Poluentes Ambientais/toxicidade , Chumbo/toxicidade , Spodoptera/fisiologia , Vitelogeninas/genética , Animais , Dieta , Poluentes Ambientais/metabolismo , Feminino , Larva/efeitos dos fármacos , Chumbo/metabolismo , Longevidade , Masculino , Mariposas , Oviposição/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Vitelogeninas/metabolismo
11.
Environ Pollut ; 270: 116237, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33412467

RESUMO

Recently, bioaccumulation of dietary organic selenium (Se) in the ovaries and inhibition of reproduction in female aquatic animals have been reported. However, there is limited data on the subtle reproductive impacts of waterborne exposure to inorganic Se in fish. Here, zebrafish embryos (2 h post-fertilization) were exposed to solutions with environmentally relevant levels of Na2SeO3 with concentrations of 0 (control), 7.98 ± 0.31, 25.14 ± 0.15, and 79.60 ± 0.81 µg Se/L for 120 d until they reached sexual maturity. Female zebrafish were selected for reproductive toxicity assessment. In the early embryonic stage, whole-mount in situ hybridization of zebrafish embryos showed that waterborne Na2SeO3 exposure did not affect the observed location of vasa expression in primordial germ cells at 24, 48, and 72 h post-fertilization. Life-cycle exposure to 25.14 ± 0.15 and 79.60 ± 0.81 µg Se/L Na2SeO3 did not change the testosterone and 17ß-estradiol contents in female zebrafish at the endpoint of exposure, but significantly reduced the proportion of early vitellogenic oocytes and mature oocytes. Follicle maturity retardation was accompanied by changes in transcriptional levels of the genes related to the hypothalamus-pituitary-gonad-liver (HPGL) axis. Transcriptional levels of cyp19a and lhr in the ovary were down-regulated, while the transcriptional level of fshr in the ovaries was up-regulated. In the 21-day cumulative spawning experiment, Na2SeO3 (25.14 ± 0.15 and 79.60 ± 0.81 µg Se/L) caused fewer eggs to be produced. Additionally, the malformation of zebrafish offspring significantly increased in the group exposed to 79.60 ± 0.81 µg Se/L. In conclusion, for the first time, this study shows that life-cycle exposure to environmentally relevant concentrations of waterborne Na2SeO3 significantly delays ovarian maturation and reduces the fertility of the female zebrafish.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Feminino , Gônadas , Estágios do Ciclo de Vida , Reprodução , Ácido Selenioso , Vitelogeninas , Poluentes Químicos da Água/toxicidade
12.
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
13.
Bull Environ Contam Toxicol ; 106(2): 289-294, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33392690

RESUMO

Phenanthrene (PHE) as a tricyclic polycyclic aromatic hydrocarbon is one of the common pollutants in water and sediments, which can cause reproductive toxicity to aquatic organisms. In this study, enzyme-linked immunosorbent assay (ELISA) was used to detect the vitellogenin (VTG) of loach, and then to explore the estrogenic toxicity effect of PHE on loach. The results were as follows: (1) with the increase of PHE concentrations and the extension of exposure time, the gonadosomatic index (GSI) of males decreased significantly, while it increased in female loaches. In addition, males had more obvious changes than females and were more sensitive to PHE. (2) The increase of VTG contents in serum of males were stronger than that in females. Those results reveal that PHE has estrogenic effect, which can affect the generation of VTG, thus causing damage to the gonad development of loach.


Assuntos
Cipriniformes , Fenantrenos , Poluentes Químicos da Água , Animais , Estrogênios/toxicidade , Feminino , Gônadas , Masculino , Fenantrenos/toxicidade , Vitelogeninas , Poluentes Químicos da Água/toxicidade
14.
Chemosphere ; 263: 128251, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297196

RESUMO

Vitellogenin (VTG) is typically produced by females but when present in males can indicate contamination with estrogenic endocrine-disrupting chemicals (EDCs). Here we used primary hepatocytes isolated from male crucian carp uncontaminated with estrogenic EDCs as a culture model. Nine EDCs were used for validation, and an enzyme-linked immunosorbent assay (ELISA) was used to quantify VTG production by primary hepatocytes. The lower limit of detection of 17ß-E2, DES, and HES using the method was 10-12 M. Fresh pork was roasted, and non-hydrolytic acetonitrile-vortexing was used to extract potential estrogenic EDCs. The extracted substances were separated by thin-layer chromatography (TLC), and dimethyl terephthalate present in roast pork was found to induce high VTG concentrations. Therefore, the detection of VTG by ELISA provides a sensitive and reliable method for detecting known and unknown estrogenic EDCs in food products.


Assuntos
Disruptores Endócrinos , Produtos da Carne , Animais , Disruptores Endócrinos/toxicidade , Ensaio de Imunoadsorção Enzimática , Estrogênios/toxicidade , Estrona , Feminino , Masculino , Vitelogeninas
15.
Aquat Toxicol ; 231: 105719, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360234

RESUMO

Numerous environmental pollutants have the potential to accumulate in sediments, and among them are endocrine-disrupting chemicals (EDCs). It is well documented that water-borne exposure concentrations of some potent EDCs, more specifically estrogenic- active compounds (ECs), can impair the reproduction of fish. In contrast, little is known about the bioavailability and effects of sediment-associated ECs on fish. Particularly, when sediments are disturbed, e.g., during flood events, chemicals may be released from the sediment and become bioavailable. The main objectives of this study were to evaluate a) whether ECs from the sediment become bioavailable to fish when the sediment is suspended, and b) whether such exposure leads to endocrine responses in fish. Juvenile rainbow trout (Oncorhynchus mykiss) were exposed over 21 days to constantly suspended sediments in the following treatments: i) a contaminated sediment from the Luppe River, representing a "hotspot" for EC accumulation, ii) a reference sediment (exhibiting only background contamination), iii) three dilutions, 2-, 4- and 8-fold of Luppe sediment diluted with the reference sediment, and iv) a water-only control. Measured estrogenic activity using in vitro bioassays as well as target analysis of nonylphenol and estrone via LC-MS/MS in sediment, water, fish plasma, as well as bile samples, confirmed that ECs became bioavailable from the sediment during suspension. ECs were dissolved in the water phase, as indicated by passive samplers, and were readily taken up by the exposed trout. An estrogenic response of fish to Luppe sediment was indicated by increased abundance of transcripts of typical estrogen responsive genes, i.e. vitelline envelope protein α in the liver and vitellogenin induction in the skin mucus. Altered gene expression profiles of trout in response to suspended sediment from the Luppe River suggest that in addition to ECs a number of other contaminants such as dioxins, polychlorinated biphenyls (PCBs) and heavy metals were remobilized during suspension. The results of the present study demonstrated that sediments not only function as a sink for ECs but can turn into a significant source of pollution when sediments are resuspended as during flood-events. This highlights the need for sediment quality criteria considering bioavailability sediment-bound contaminants in context of flood events.


Assuntos
Estrogênios/toxicidade , Sedimentos Geológicos/química , Oncorhynchus mykiss/metabolismo , Animais , Disponibilidade Biológica , Exposição Ambiental , Feminino , Ontologia Genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade
16.
J Insect Sci ; 20(6)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33367730

RESUMO

Oviposition-related genes have remained a consistent focus of insect molecular biology. Previous research has gradually clarified our mechanistic understanding of oviposition-related genes, including those related to oviposition-gland-related genes, oogenesis-related genes, oviposition-site-selection-related genes, and genes related to ovulation and hatching. Moreover, some of this research has revealed how the expression of single oviposition-related genes affects the expression of related genes, and more importantly, how individual node genes function to link the expression of upstream and downstream genes. However, the research to date is not sufficient to completely explain the overall interactions among the genes of the insect oviposition system. Through a literature review of a large number of studies, this review provides references for future research on oviposition-related genes in insects and the use of RNAi or CRISPR/Cas9 technology to verify the functions of oviposition-related genes and to prevent and control harmful insects.


Assuntos
Insetos/genética , Oviposição/genética , Animais , Sistemas CRISPR-Cas , Proteínas do Ovo/genética , Feminino , Expressão Gênica , Genes de Insetos , Controle de Insetos/métodos , Oogênese/genética , Interferência de RNA , Receptores de Superfície Celular/genética , Vitelogeninas/genética
17.
Nat Commun ; 11(1): 4627, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009389

RESUMO

Animals have evolved responses to low oxygen conditions to ensure their survival. Here, we have identified the C. elegans zinc finger transcription factor PQM-1 as a regulator of the hypoxic stress response. PQM-1 is required for the longevity of insulin signaling mutants, but surprisingly, loss of PQM-1 increases survival under hypoxic conditions. PQM-1 functions as a metabolic regulator by controlling oxygen consumption rates, suppressing hypoxic glycogen levels, and inhibiting the expression of the sorbitol dehydrogenase-1 SODH-1, a crucial sugar metabolism enzyme. PQM-1 promotes hypoxic fat metabolism by maintaining the expression of the stearoyl-CoA desaturase FAT-7, an oxygen consuming, rate-limiting enzyme in fatty acid biosynthesis. PQM-1 activity positively regulates fat transport to developing oocytes through vitellogenins under hypoxic conditions, thereby increasing survival rates of arrested progeny during hypoxia. Thus, while pqm-1 mutants increase survival of mothers, ultimately this loss is detrimental to progeny survival. Our data support a model in which PQM-1 controls a trade-off between lipid metabolic activity in the mother and her progeny to promote the survival of the species under hypoxic conditions.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Hipóxia/metabolismo , Metabolismo dos Lipídeos , Transativadores/metabolismo , Animais , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica , Glicogênio/metabolismo , Insulina/metabolismo , Larva/metabolismo , Mutação/genética , Consumo de Oxigênio , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida , Transativadores/genética , Transcrição Genética , Vitelogeninas/metabolismo
18.
Bull Environ Contam Toxicol ; 105(5): 692-698, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33040230

RESUMO

Effluents from on-site wastewater treatment systems can influence surface water quality, particularly when infrastructure is aging, malfunctioning, and improperly installed. Municipal wastewater often contains chemical compounds that can lead to adverse biological effects, such as reproductive impairment, in organisms that are chronically exposed. A significant number of these compounds are endocrine-disrupting chemicals. Water quality influences of on-site systems are poorly studied in semi-arid regions where instream flows are seasonally dependent on snowmelt, and when instream dilution of wastewater effluents is minimal during other times of the year. Here we examined surface water estrogenicity in low order tributaries of two unique semi-arid streams with on-site wastewater treatment systems, for which seasonal instream flow fluctuations occur in Park City, UT, USA. Water samples were collected from a total of five locations along two lotic systems downstream from active on-site treatment systems. Samples were extracted for targeted chemical analyses and to perform in vivo and in vitro bioassays with juvenile rainbow trout. Estrogenic activity was measured by quantifying the concentration and expression of vitellogenin (VTG) in plasma and liver, respectively. Plasma VTG presented elevated levels in fish exposed to water samples collected at the two sites in close proximity to on-site systems and during seasons with low stream discharge, though the levels observed did not suggest severe endocrine disruption. However, long-term exposure to these surface water could compromise the fish populations. While the sensitivity of in vitro bioassays was low and targeted chemical analyses did not identify causative compounds, the use of complementary lines of evidence (e.g., in vivo biological models) was advantageous in identifying estrogenic activity in waters influenced by effluents from on-site wastewater systems.


Assuntos
Disruptores Endócrinos/toxicidade , Oncorhynchus mykiss/sangue , Rios/química , Neve/química , Vitelogeninas/sangue , Poluentes Químicos da Água/toxicidade , Animais , Cidades , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Modelos Teóricos , Estações do Ano , Utah , Vitelogeninas/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água , Qualidade da Água
19.
Aquat Toxicol ; 227: 105586, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32882451

RESUMO

Estrogenic effects triggered by androgens have been previously shown in a few studies. Aromatization and direct binding to estrogen receptors (ERs) are the most proposed mechanisms. For example, previously, a modulation of vitellogenin A (VtgA) by testosterone (T), an aromatizable androgen, was reported in brown trout primary hepatocytes. The effect was reversed by an ER antagonist. In this study, using the same model the disruption caused by T and by the non-aromatizable androgen - dihydrotestosterone (DHT), was assessed in selected estrogenic targets. Hepatocytes were exposed (96 h) to six concentrations of each androgen. The estrogenic targets were VtgA, ERα, ERß1 and two zona pellucida genes, ZP2.5 and ZP3a.2. The aromatase CYP19a1 gene and the androgen receptor (AR) were also included. Modulation of estrogenic targets was studied by quantitative real-time PCR and immunohistochemistry, using an HScore system. VtgA and ERα were up-regulated by DHT (1, 10, 100 µM) and T (10, 100 µM). In contrast, ERß1 was down-regulated by DHT (10, 100 µM), and T (100 µM). ZP2.5 mRNA levels were increased by DHT and T (1, 10, 100 µM), while ZP3a.2 was up-regulated by DHT (100 µM) and T (10, 100 µM). Positive correlations were found between VtgA and ERα mRNA levels and ZPs and ERα, after exposure to both androgens. The mRNA levels of CYP19a1 were not changed, while AR expression tended to increase after micromolar DHT exposures. HScores for Vtg and ZPs corroborated the molecular findings. Both androgens triggered estrogen signaling through direct binding to ERs, most probably ERα.


Assuntos
Androgênios/toxicidade , Di-Hidrotestosterona/toxicidade , Estrogênios/metabolismo , Hepatócitos/efeitos dos fármacos , Testosterona/toxicidade , Truta/metabolismo , Poluentes Químicos da Água/toxicidade , Androgênios/metabolismo , Animais , Células Cultivadas , Di-Hidrotestosterona/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Estrogênios/genética , Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Cultura Primária de Células , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Testosterona/metabolismo , Vitelogeninas/genética , Vitelogeninas/metabolismo , Poluentes Químicos da Água/metabolismo
20.
Aquat Toxicol ; 227: 105590, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32891021

RESUMO

The aim of the present study was to investigate effects of defined mixtures of polycyclic aromatic hydrocarbons (PAHs) and perfluoroalkyl substances (PFASs), at low, environmentally relevant (1× = L), or high (20× = H) doses, on biological responses in Atlantic cod (Gadus morhua). To this end, farmed juvenile cod were exposed at day 0 and day 7 via intraperitoneal (i.p.) injections, in a two-week in vivo experiment. In total, there were 10 groups of fish (n = 21-22): two control groups, four separate exposure groups of PAH and PFAS mixtures (L, H), and four groups combining PAH and PFAS mixtures (L/L, H/L, L/H, H/H). Body burden analyses confirmed a dose-dependent accumulation of PFASs in cod liver and PAH metabolites in bile. The hepatosomatic index (HSI) was significantly reduced for three of the combined PAH/PFAS exposure groups (L-PAH/H-PFAS, H-PAH/L-PFAS, H-PAH/H-PFAS). Analysis of the hepatic proteome identified that pathways related to lipid degradation were significantly affected by PFAS exposure, including upregulation of enzymes in fatty acid degradation pathways, such as fatty acid ß-oxidation. The increased abundances of enzymes in lipid catabolic pathways paralleled with decreasing levels of triacylglycerols (TGs) in the H-PFAS exposure group, suggest that PFAS increase lipid catabolism in Atlantic cod. Markers of oxidative stress, including catalase and glutathione S-transferase activities were also induced by PFAS exposure. Only minor and non-significant differences between exposure groups and control were found for cyp1a and acox1 gene expressions, vitellogenin concentrations in plasma, Cyp1a protein synthesis and DNA fragmentation. In summary, our combined proteomics and lipidomics analyses indicate that PFAS may disrupt lipid homeostasis in Atlantic cod.


Assuntos
Fluorcarbonetos/toxicidade , Gadus morhua/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bile/metabolismo , Biomarcadores/metabolismo , Fluorcarbonetos/análise , Lipidômica , Fígado/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Proteoma/metabolismo , Proteômica , Vitelogeninas/metabolismo , Poluentes Químicos da Água/análise
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