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1.
Ecotoxicol Environ Saf ; 212: 112007, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540337

RESUMO

Microplastic (MP) pollution and the related impacts on aquatic species have drawn worldwide attention. However, knowledge of the kinetic profiles of MPs in fish remains fragmentary. In this study, we conducted exposure and depuration tests of the following fluorescent-labeled MPs: polyethylene (PE; sphere with 200 or 20 µm diameter) and polystyrene (PS; sphere with 20 or 2 µm diameter) using juvenile Japanese medaka (Oryzias latipes). The distribution and concentration of MPs in medaka were directly determined in-situ after tissue transparency. During the 14-day exposure, MPs was mainly detected in the gastrointestinal tract, while some MPs at the size of ≤ 20 µm were located in the area of the gills and head. The bioconcentration factor (BCF; L/kg) for MPs in medaka was estimated as 74.4 (200 µm PE), 25.7 (20 µm PE), 16.8 (20 µm PS), and 139.9 (2 µm PS). Within the first five days of depuration, MPs were exponentially eliminated from the fish body, but 2 µm PS-MPs could be still detected in the gastrointestinal tract at the end of the 10-day depuration phase. Our results suggest that MPs 2 µm in diameter may pose ecological risks to aquatic species due to their relatively higher BCF and the potential for long-term persistence in the body.

2.
Ecotoxicol Environ Saf ; 208: 111747, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396073

RESUMO

Residues of the psychoactive drug diazepam (DZP) may pose potential risks to fish in aquatic environments, especially by disrupting their behavioral traits. In this study, female and male zebrafish were subjected to chronic exposure (21 days) to sublethal doses (120 and 12 µg/L) of DZP, aimed to compare the characteristics of their behavioral responses to DZP exposure, and to investigate the possible links between those behavioral responses and variations in their brain γ-aminobutyric acid (GABA) and acetylcholinesterase (AChE) levels. Chronic exposure to DZP significantly decreased the swimming velocity and locomotor activity of both genders, indicating a typical sedative effect. Compared with males, whose locomotor activity was only significantly decreased by exposure to DZP for 21 days, females became hypoactive on day 14 (i.e., more sensitive), and they developed tolerance to the hypoactive effect induced by 120 µg/L DZP by day 21. Exposure to DZP significantly disturbed the behavioral traits related to social interactions in females but not in males. Those results indicate that DZP exhibits sex-dependent effects on the behaviors of fish. Moreover, exposure to DZP for 21 days significantly disturbed almost all of the tested behavioral traits associated with courtship when both genders were put together. Sex-dependent responses in brain GABA and AChE levels due to DZP exposure were also identified. Significant relationships between the brain GABA/AChE levels and some behavioral parameters related to locomotor activity were detected in females, but not in males.


Assuntos
Diazepam/toxicidade , Testes de Toxicidade Crônica , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Diazepam/administração & dosagem , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Natação , Peixe-Zebra/metabolismo , Ácido gama-Aminobutírico/farmacologia
3.
Food Chem Toxicol ; 149: 112003, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33484791

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP), one of the most common plasticizers, is closely associated with a high prevalence of pubertal type 2 diabetes mellitus (T2DM). Numerous studies have indicated that DEHP-induced metabolic toxicity exhibits sex differences. In this study, the sex differences in the effect of DEHP on pubertal T2DM (P-T2DM) mice, the susceptibility of female P-T2DM mice to DEHP-induced metabolic toxicity, and the underlying mechanisms were investigated. DEHP exposure exacerbated metabolic disorders in female P-T2DM mice. Factorial analysis showed that female P-T2DM mice were more sensitive to DEHP exposure than female normal mice and male P-T2DM mice. It was determined by integrated biomarker response results that female P-T2DM mice had higher risks of developing T2DM, metabolic disorders, cardiovascular events and hepatotoxicity than male P-T2DM mice. Moreover, hepatic transcriptome analysis emphasized the effects of DEHP on the expression of oxidative injury- and metabolic function-related genes. Western blotting indicated that DEHP activated Jun-N-terminal kinase (JNK) and impaired insulin sensitivity in the liver, which were the main causes of DEHP-exacerbated metabolic abnormalities in P-T2DM mice. Our study revealed that compared with normal mice and male P-T2DM mice, female P-T2DM mice tend to suffer from increased DEHP-induced metabolic toxicity, which was primarily attributed to hepatotoxicity.

4.
J Sci Food Agric ; 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33448409

RESUMO

BACKGROUND: The ultrasensitive monitoring strategy of zearalenone (ZEN) is essential and desirable for food safety and human health. In the present study, a coupling of gold nanoparticles-DNA barcode and direct competitive immunoassay-based real-time polymerase chain reaction signal amplification (RT-IPCR) for ZEN close to the sensitivity of PCR-like levels is described and evaluated. RESULTS: The RT-IPCR benefited from the use of a DNA barcode and RT-PCR detection strategy, thus resulting in ultrasensitive and simple detection for ZEN. Under the optimal RT-IPCR, the linear range of detection was from 0.5 to 1000 pg mL-1 and the limit of detection was 0.5 pg mL-1 , which was 400-fold lower than the enzyme-linked immunosorbent assay. The detection procedure was simplified and the detection time was shortened. The specificity, accuracy and precision of the RT-IPCR confirmed a high performance. ZEN-positive contamination levels were from 0.056 to 152.12 ng g-1 by the RT-IPCR, which was demonstrated to be highly reliable by liquid chromatography-tandem mass spectrometry. CONCLUSION: The proposed RT-IPCR could be used as an alternative for detecting ZEN with satisfactory ultrasensitivity, simplicity, low cost and high-throughput. The present study could provide a strategy for the ultrasensitive detection of the small molecule with a simple and practical approach, which has significant appeal and application prospects.

5.
Chemosphere ; 262: 128045, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182117

RESUMO

The vulnerability to environmental insults is heightened at early stages of development. However, the neurotoxic potential of bisphenol A (BPA) and bisphenol S (BPS) at developmental windows remains unclear. To investigate the mechanisms mediating the developmental neurotoxicity, zebrafish embryos were treated with 0.01, 0.03, 0.01, 0.3, 1 µM BPA/BPS. Also, we used Tg(HuC:GFP) zebrafish to investigate whether BPA/BPS could induce neuron development. The reduction in body length, and increased heart rate were significant in 0.3 and 1 µM BPA/BPS groups. The green fluorescence protein (GFP) intensity increased at 72 hpf and 120 hpf in Tg(HuC:GFP) larvae which was consistent with the increased mRNA expression of elval3 following BPS treatments, an indication of the plausible effect of BPS on embryonic neuron development. Additionally, BPA/BPS treatments elicited hyperactivity and reduced static time in zebrafish larvae, suggesting behavioral alterations. Moreover, qRT-PCR results showed that BPA and BPS could interfere with the normal expression of development-related genes vegfa, wnt8a, and mstn1 at the developmental stages. The expression of neurodevelopment-related genes (ngn1, elavl3, gfap, α1-tubulin, mbp, and gap43) were significantly upregulated in BPA and BPS treatments, except for the remarkable downregulation of mbp and gfap elicited by BPA at 48 (0.03 µM) and 120 hpf (0.3 µM) respectively; ngn1 at 48 hpf for 0.1 µM BPS. Overall, our results highlighted that embryonic exposure to low concentrations of BPA/BPS could be deleterious to the central nervous system development and elicit behavioral abnormalities in zebrafish at developmental stages.


Assuntos
Compostos Benzidrílicos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Fenóis/toxicidade , Sulfonas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Embrião não Mamífero/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
6.
Aquat Toxicol ; 228: 105643, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33017738

RESUMO

To better assess the risk of microplastics (MPs) as a vector for contaminants, it is essential to understand the relative importance of MPs compared to other pathways for chemical transfer as well as the consequences of co-exposure. In this study, we exposed Japanese medaka (Oryzias latipes) to anthracene (ANT, 0.1 mg/L) in the presence or absence of pristine polyethylene MPs (PE-MPs, 106 beads/L), to quantify the vector effect of PE-MPs on ANT accumulation. Under the ANT-MPs co-exposure conditions, PE-MPs rapidly accumulated in the gastrointestinal tract of the medaka during a 14-day uptake phase, with an average bioconcentration factor of 171.4 L/kg. The PE-MPs could absorb and accumulate approximately 70 % of the ANT from the water sample. The PE-MPs changed the pharmacokinetic profile of ANT in medaka by decreasing both the uptake and depuration rate constants. The one compartment with first-order elimination model estimated that the amounts of ANT in the water phase and absorbed by PE-MPs (i.e., a vector effect) contributed about 67 % and 33 % of the ANT accumulation in medaka, respectively. At the end of the uptake (exposure) phase, however, the presence of PE-MPs did not significantly alter the final ANT concentrations in the fish body or alter the behavioral impacts of ANT. Thus, PE-MPs ingestion may act as a vector to concentrate and transfer ANT to medaka, but the presence of these particles may have limited adverse effects on fish under co-exposure systems of the type used in this study.


Assuntos
Antracenos/toxicidade , Monitoramento Ambiental , Microplásticos/análise , Oryzias/metabolismo , Polietileno/análise , Animais , Antracenos/farmacocinética , Poluentes Químicos da Água/toxicidade
7.
Sci Total Environ ; 740: 140392, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927558

RESUMO

Environmental pollution by the psychoactive drug diazepam (DZP) has been suggested to disrupt various behavioral traits of fishes. Exposure to DZP in natural waters may be of episodic duration, but there are few reports on the persistence of abnormal behaviors of fishes caused by such acute exposure. In the current study, we exposed juvenile zebrafish (Danio rerio) to sublethal doses of DZP (1200, 120, and 12 µg/L) for four days and evaluated their behavioral traits and brain γ-aminobutyric acid (GABA) levels at days 0 (i.e., immediately after the 4-day exposure), 7, and 21 of the recovery period. Exposure to DZP induced short-term impairment of swimming ability and two-fish interactions of zebrafish. In contrast, DZP induced persistent and/or delayed effects on locomotor activity of zebrafish, i.e., hypoactivity at 1200 µg/L and hyperactivity at 120 and 12 µg/L, that could be still observed on days 7 and/or 21 during the recovery period. DZP exposure also exhibited concentration-specific effects on brain GABA levels in zebrafish, i.e., decreased at 1200 µg/L and increased at 120 and 12 µg/L. Correlation analysis suggested that the changes in brain GABA levels may contribute to the persistence of abnormalities in the locomotor activity of zebrafish. Our findings suggest that zebrafish need a long time to recover from acute exposure to DZP, thus highlighting that the persistence of behavioral abnormalities induced by such psychoactive drugs should be considered in order to better assess their risks in natural ecosystems.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Encéfalo , Diazepam , Ecossistema , Ácido gama-Aminobutírico
8.
Mar Pollut Bull ; 158: 111446, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753222

RESUMO

This study was performed to elucidate the uptake and bioaccumulation of polystyrene microplastics (PS-MPs) in Japanese medaka (freshwater fish) and Java medaka (marine fish), and to assess its impacts on the survival, reproduction, and gene expression of Japanese medaka. Both species were exposed to 2-µm fluorescent PS-MPs (107 beads/L) for 3 weeks. The bioaccumulation factor of PS-MPs for Java medaka was calculated at about 4 × 102, higher than that for Japanese medaka (about 1 × 102). The exposure had no significant effects on the survival and reproduction of Japanese medaka. The mRNA sequencing analysis showed that the expression of a few genes involved in the cell adhesion, xenobiotic metabolic process, brain development, and other functions in medaka intestines significantly changed after exposure. These results suggest that virgin PS-MPs can potentially accumulate in medaka intestines, but has limited toxicity to Japanese medaka at the concentration up to 107 beads/L.


Assuntos
Oryzias , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Microplásticos , Plásticos
9.
Mar Pollut Bull ; 159: 111445, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32758797

RESUMO

Tributyltin-binding protein type 2 (TBT-bp2), a homolog of α1-acid glycoprotein, may contribute to both accumulation and detoxification of TBT in fish. In this study, we conducted acute TBT exposure tests using both wide-type (WT) and TBT-bp2-/- (KO) strains of medaka and compared their responses in survival time and accumulation of TBT. Deficiency of TBT-bp2 significantly accelerated the time to death of medaka and decreased the LC50 of TBT, indicating that the KO-strain is more sensitive to TBT. No significant difference in the intrinsic TBT concentration in surviving fish was observed between the two strains. However, the intrinsic TBT concentration in dead KO-strain was significantly lower than that in WT-strain. These findings provide direct evidence, supporting the hypothesis that TBT-bp2 plays a critical role in the detoxification of TBT in fish.


Assuntos
Diabetes Mellitus Tipo 2 , Oryzias , Compostos de Trialquitina , Animais , Proteínas de Transporte
10.
Chemosphere ; 258: 127238, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32563064

RESUMO

Dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) are phthalate compounds frequently detected in the environment. Despite increasing awareness of their toxicity in human and animals, the male reproductive toxicity of their combined exposure remains elusive. The purposes of this study were to investigate whether combined exposure to DBP and DiBP could induce male reproductive toxicity, and to explore the potential toxicological mechanisms. Adult male zebrafish were exposed to DBP (11, 113 and 1133 µg L-1), DiBP (10, 103 and 1038 µg L-1) and their mixtures (Mix) (11 + 10, 113 + 103, 1133 + 1038 µg L-1) for 30 days, and their effects on plasma hormone secretion, testis histology and transcriptomics were examined. Highest concentrations of Mix exposure caused greater imbalance ratio of T/E2 and more severe structural damage to testis than single exposure. These effects were consistent with the testis transcriptome analysis for which 4570 genes were differentially expressed in Mix exposure, while 2795 and 1613 genes were differentially expressed in DBP and DiBP, respectively. KEGG pathway analysis showed that both single and combined exposure of DBP and DiBP could affect cytokine-cytokine receptor interaction. The difference was that combined exposure could also affect steroid hormone synthesis, extracellular matrix receptor interaction, retinol metabolism, and PPAR signaling pathways. These results demonstrated that combined exposure to DBP and DiBP could disrupt spermatogenesis and elicit male reproductive toxicity in zebrafish.


Assuntos
Dibutilftalato/análogos & derivados , Dibutilftalato/toxicidade , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Humanos , Masculino , Modelos Teóricos , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética , Testículo/metabolismo
11.
Harmful Algae ; 94: 101808, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32414504

RESUMO

Chattonella spp. are known to produce large amounts of reactive oxygen species (ROS); however, little is known about the mechanisms involved in mitigating the intracellular accumulation of ROS. In this study, a time-series of biological responses in C. marina var. antiqua under different oxidative stress conditions, induced by adding H2O2 at the initial concentrations of 100 and 500 µM, was investigated. Although the added exogenous H2O2 was rapidly consumed at 3 h post-exposure (hpe), intracellular ROS levels were enhanced in the 500 µM H2O2 group but decreased in the 100 µM H2O2 group. Accompanied by increased intracellular ROS levels, the photosynthetic activity of C. marina var. antiqua was considerably inhibited in the 500 µM H2O2 group, but not in the 100 µM H2O2 group. The Fv/Fm ratio and PIABS were negatively correlated with the intracellular ROS level, while the ABS/RC, TR0/RC, and DI0/RC were positively correlated with the intracellular ROS level. Expression of the gene encoding 2-cysteine peroxiredoxin (2-Cys Prx) was up-regulated in 100 µM H2O2 group at 6 hpe, but was down-regulated in 100 µM H2O2 group at 3 and 6 hpe. A negative relationship between the 2-Cys Prx transcript levels and intracellular ROS levels was detected. Results of the 2-DE proteomic analysis confirmed that the 500 µM H2O2 treatment down-regulated the expression of 2-Cys Prx and induced more damage to photosynthetic abilities of C. marina var. antiqua.


Assuntos
Cisteína , Peroxirredoxinas , Cisteína/metabolismo , Peróxido de Hidrogênio , Estresse Oxidativo , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Proteômica
12.
Artigo em Inglês | MEDLINE | ID: mdl-32376496

RESUMO

Pufferfish saxitoxin and tetrodotoxin binding proteins (PSTBPs) play an important role in the toxification of certain species of pufferfish. Recombinant Takifugu rubripes PSTBP1 (rTrub.PSTBP1) is reported to bind to tributyltin, and so it has been suggested that rTrub.PSTBP1 may reduce the toxicity of tributyltin. However, the role of PSTBP1 in vivo remains to be elucidated. Here, we established a transgenic medaka line showing whole-body Renilla reniformis green fluorescent protein and Trub.PSTBP1 expression, as confirmed by real-time polymerase chain reaction and mRNA-Seq analysis. mRNA-Seq analysis also showed that cytochrome P450 superfamily genes and the gene encoding ATP-binding cassette sub-family G member 2 were highly expressed in the transgenic medaka. Using embryos of the transgenic medaka line, we conducted an in ovo nanoinjection test to examine the effect of Trub.PSTBP1 in vivo, and obtained data suggesting that Trub.PSTBP1 expression may have reduced the toxicity of tributyltin in our transgenic medaka line. Our findings will be useful for future functional analyses of Trub.PSTBP1.

13.
Arch Toxicol ; 94(4): 1279-1302, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32303808

RESUMO

In the present study, the neurotoxicity and mechanisms of di-(2-ethylhexyl) phthalate (DEHP) exposure on pubertal normal (P-normal) and pubertal type 2 diabetes mellitus (P-T2DM) mice were investigated by typical neurobehavioral methods and transcriptome analysis. Pubertal male ICR mice were orally exposed to DEHP (0.18, 1.8, 18 and 180 mg/kg/d) for 3 weeks. In Open field test, DEHP significantly increased the time in central area staying and decreased the total distance and clockwise (CW) rotation of P-normal and P-T2DM mice. Morris water maze showed that DEHP significantly increased the latency in locating platform and decreased the original platform quadrant and residence time in target quadrant of P-normal and P-T2DM mice. Transcriptome analysis results revealed the effects of DEHP exposure on neural signaling pathway including biogenic amines neurotransmitters, nerve receptors, neurobiological processes, etc. Enzyme-linked immunosorbent assay (ELISA) and western blotting results showed that DEHP significantly decreased the contents of 5-HT, cAMP, GABA and Ca2+, the levels of CREB, phosphorylation of PKA, ERK1/2 and CREB, increased the levels of CaM and phosphorylation of CaMKII in P-normal and P-T2DM mice. Factorial analysis results showed that P-T2DM mice were more sensitive than those of P-normal mice. The potential neurotoxicity mechanism of DEHP may be synergistically mediated by the cAMP-PKA-ERK1/2-CREB signaling and the Ca2+ signaling pathway.

14.
Mar Pollut Bull ; 152: 110896, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31957673

RESUMO

Being the precursor of serotonin and melatonin, dietary supplementation with tryptophan (TRP) may modulates behavior, stress responses, and antioxidant capacity in fish. In this study, effects of Chattonella exposure on the swimming behavior and brain monoamine metabolism of yellowtail fed a commercial diet (control diet) or that enriched by 1.5% L-TRP (TRP + diet) were investigated. A 7-day dietary TRP supplementation elevated spontaneous swimming speed of yellowtail and mitigated their behavioral response to Chattonella (250 cells/mL) exposure. A 30-day dietary TRP supplementation elevated growth of juvenile yellowtail. Lethal exposure to Chattonella (1000 cells/mL) significantly elevated the turnover rates of serotonin, dopamine, and norepinephrine metabolism in fish fed control diet, but did not alter the serotonin turnover rate in fish fed TRP + diet. Our results suggested that dietary supplementation with TRP had potential to mitigate the stress response in yellowtail to Chattonella, partly via mediating their brain monoamine metabolism.


Assuntos
Estramenópilas , Natação , Animais , Encéfalo , Peixes , Triptofano
15.
Arch Toxicol ; 93(11): 3183-3206, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31606821

RESUMO

The prevalence of adolescent type 2 diabetes mellitus (A-T2DM) is increasing year by year. Di-(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, could exacerbate type 2 diabetes mellitus (T2DM). The study aimed to investigate the metabolic toxicity, susceptibility and mechanism of DEHP exposure to A-T2DM. DEHP was administered orally (0, 0.18, 1.8, 18, and 180 mg/kg/day) for 3 weeks to adolescent normal mice (A-normal mice) and established A-T2DM mice. The results of fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) levels showed that the susceptibility of A-T2DM mice to DEHP exposure was more significant than that of A-normal mice. DEHP, interfering with glucose and lipid metabolism of A-normal and A-T2DM mice, caused the body weight increase of A-normal mice and decrease of A-T2DM mice. Besides, DEHP could cause more injury of cardiovascular, hepatic and renal function to A-T2DM mice than A-normal mice. Hepatic transcriptome analysis revealed that DEHP exposure interfered with the biological feedback adjustment of endocrine and metabolic system in A-T2DM mice and then led to the development of T2DM. According to the transcriptome results, insulin signaling transduction pathway was applied and researched by immunoassay. It was discovered that DEHP reduced insulin sensitivity and disturbed insulin signaling transduction, glucose utilization, lipid synthesis and protein synthesis. Collectively, DEHP could disturb the endocrine and metabolic functions and increase the insulin resistance in adolescent mice. Moreover, the adolescent T2DM mice are more sensitive to DEHP-induced endocrine and metabolic toxicity than the healthy adolescent mice.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 2/induzido quimicamente , Dietilexilftalato/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Plastificantes/toxicidade , Transcriptoma/efeitos dos fármacos , Animais , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Glucose/metabolismo , Resistência à Insulina/genética , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR
16.
Aquat Toxicol ; 216: 105290, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31518775

RESUMO

Phthalate esters (PAEs), which are notable plasticizers, can be prolific contaminants in aquatic environments, and have been shown to induce reproductive toxicity. However, the studies concerning their toxicity towards aquatic species are based on individual chemicals, and the combined toxicity of PAEs to aquatic organisms remains unclear. The aim of this study was to explore the potential toxicity mechanisms associated with combined exposure to dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) in adult female zebrafish ovaries. Zebrafish were exposed to DBP, DiBP and their mixtures for 30 days, and their effects on ovarian histology, plasma sex hormones and ovarian transcriptomics were investigated. Plasma estradiol (E2) levels were significantly decreased by 38.9% in the DBP-1133 exposure group and 41.0% in the DiBP-1038 exposure group. The percentage of late/mature oocytes was also significantly decreased by 17.3% under DBP-1133 exposure and 16.2% under DiBP-1038 exposure, while that under combined exposure was not significantly affected. Nevertheless, transcriptome sequencing revealed 2564 differentially expressed genes (DEGs) in zebrafish ovaries after exposure to the mixtures. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were involved in the neuroactive ligand-receptor interaction, GnRH, progesterone-mediated oocyte maturation, oocyte meiosis and steroid hormone biosynthesis signaling pathways. These results revealed that combined exposure exerts potential reproductive toxicity at the molecular level.


Assuntos
Dibutilftalato/análogos & derivados , Dibutilftalato/toxicidade , Exposição Ambiental , Perfilação da Expressão Gênica , Ovário/metabolismo , Transcriptoma/genética , Peixe-Zebra/genética , Animais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Hormônios Esteroides Gonadais/sangue , Ovário/efeitos dos fármacos , Ovário/patologia , Reprodutibilidade dos Testes , Reprodução/efeitos dos fármacos , Reprodução/genética , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/sangue
17.
Chemosphere ; 220: 687-695, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30605811

RESUMO

The ubiquitous environmental obesogens tributyltin (TBT) and perfluorooctane sulfonate (PFOS) may accumulate in parent and be transferred to their offspring, resulting in trans-generational adverse effects. In this study, we investigated the combined toxic and obesogenic effects of TBT and PFOS on the early life stages of Japanese medaka (Oryzias latipes). In ovo nanoinjection was used to simulate the maternal transfer process. Doses were controlled at 0, 0.05, 0.5, and 2.5 ng/egg (TBT) and at 0, 0.05, 0.5, and 5.0 ng/egg (PFOS), with a full factorial design for mixture formulations. Relatively high doses of agents in mixtures were needed to induce significant mortality (TBT ≥ 0.5 ng/egg) or delayed hatching (PFOS = 5.0 ng/egg) of embryos. The interaction between TBT and PFOS in mixtures had significant effects on the observed hatching delay, but not on acute mortality. Compared with controls, separate exposure to TBT (or PFOS) notably elevated adipose areas at the doses of 0.05 and 0.5 ng/egg, but not at the highest doses. Combined exposure significantly promoted the fat accumulation in newly hatched larvae, even when the doses of TBT and PFOS were both at the levels that did not show obesogenic effect. The interactive effect of TBT and PFOS could aggravate the total obesogenic effect of their mixtures, indicating a synergistic interaction. These results highlight the importance of paying close attention to interaction effects when addressing the impacts of mixtures of environmental obesogens.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Ácidos Alcanossulfônicos/farmacologia , Fluorcarbonetos/farmacologia , Oryzias/metabolismo , Compostos de Trialquitina/farmacologia , Tecido Adiposo/crescimento & desenvolvimento , Animais , Sinergismo Farmacológico , Embrião não Mamífero/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Exposição Materna/efeitos adversos , Obesidade/induzido quimicamente , Oryzias/embriologia
18.
Environ Sci Pollut Res Int ; 25(25): 25363-25370, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29946846

RESUMO

The present study investigated how principal environmental factors such as temperature and light intensity change the toxicological properties of thiobencarb (TB) herbicide to the green alga, Raphidocelis subcapitata. At first, we investigated the inhibitory effect of TB (0, 15.6, 31.2, 62.4, and 125 µg L-1) on growth of R. subcapitata at five temperatures (10, 15, 20, 25, or 30 °C) for 144 h exposure and calculated 72- and 144-h effective concentration values (EC10, 20, and EC50) for growth rate. All EC values significantly decreased with an increasing temperature. The maximum quantum yield of photosystem II in R. subcapitata exposed to 125 µg L-1 of TB was also significantly inhibited with increased temperature. These physiological effects could explain the lower EC values at high temperatures. Then, single and interactive effects of TB, temperature, and light intensity on growth rate were investigated by three-way of analysis of variance. As a result, single and interactive effects were detected in all explanatory variables. These results suggest that temperature and light intensity change the acute toxicity parameter in R. subcapitata exposed to TB and must be considered in evaluating the risk of TB.


Assuntos
Clorofíceas/efeitos dos fármacos , Herbicidas/toxicidade , Luz , Temperatura , Tiocarbamatos/toxicidade , Poluentes Químicos da Água/toxicidade , Água , Complexo de Proteína do Fotossistema II
19.
Chemosphere ; 193: 313-320, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29145093

RESUMO

Bisphenol A (BPA) and di-n-butyl phthalate (DBP) are well-known endocrine-disrupting chemicals (EDCs) that have human health risks. Chronic exposure to BPA and DBP increases the occurrence of human disease. Despite the potential for exposure in embryonic development, the mechanism of action of BPA and DBP on vertebrate development and disease still remains unclear. In the present study, we identified proteins and protein networks that are perturbed by BPA and DBP during zebrafish (Danio rerio) development. Zebrafish embryos were exposed to environmentally relevant levels of BPA (10 µg/L) and DBP (50 µg/L) for 96 h. By iTRAQ labeling quantitative proteomics, a set of 26 and 41 differentially expressed proteins were identified in BPA- and DBP-treated zebrafish embryos, respectively. Integrated toxicity analysis predicted that these proteins function in common regulatory networks that are significantly associated with developmental and metabolic disorders. Exposure to low concentrations of BPA and DBP has potential health risks in zebrafish embryos. Our results also show that BPA and DBP significantly up-regulate the expression levels of multiple network proteins, providing valuable information about the molecular actions of BPA and DBP on the developmental systems.


Assuntos
Compostos Benzidrílicos/toxicidade , Dibutilftalato/toxicidade , Fenóis/toxicidade , Proteômica , Animais , Dibutilftalato/metabolismo , Embrião não Mamífero , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Humanos , Proteoma/análise , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
20.
Aquat Toxicol ; 192: 148-154, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28957716

RESUMO

Although most exposures to chlorpyrifos (CPF) in natural flowing waters are brief and episodic, there have been a few reports of the persistence of abnormal fish behaviors caused by such acute exposure. The present study focused on the behavioral and biochemical responses of Japanese medaka (Oryzias latipes) to acute, sublethal exposure to CPF, as well as the persistence of the effects during a 3-week recovery test in CPF-free water. The medaka became hyperactive and exhibited an elevated anxiety state after a 4-day exposure to 0.024mg/L of CPF, but they recovered from these abnormal behavioral responses within 7days of recovery treatment. In contrast, persistent impacts on some startle responses to a sudden stimulation (induced by a ball drop) were observed in medaka exposed to CPF. The reaction latency did not change immediately after the 4-day exposure, but was significantly prolonged by as much as 21days after the termination of exposure. The post-stimulus swimming distance within 5s significantly decreased on the day immediately after the 4-day exposure, but it significantly increased after 7days of recovery treatment. The activity of acetylcholinesterase (AChE) in the brains of medaka was significantly inhibited on the day immediately after the 4-day exposure, but it returned to 80% and 110% of that in control fish on days 7 and 21 of the recovery period, respectively. However, AChE activities in the eyes of exposed medaka were persistently inhibited and declined to 33%, 71%, and 72% of that in control fish on days 0 (immediately after the 4-day exposure), 7, and 21 of recovery, respectively. Correlation analysis suggested that the changes of AChE activities in the brains of medaka may underlie some of the observed acute behavioral changes, and the changes of AChE activities in the eyes may contribute to the persistence of the abnormalities in the reaction latency of the startle response. Our findings suggest that medaka need a long time to recover from acute, sublethal exposure to CPF, and the persistence of the behavioral abnormalities might affect their fitness in natural habitats.


Assuntos
Ansiedade/fisiopatologia , Comportamento Animal/efeitos dos fármacos , Clorpirifos/toxicidade , Locomoção/efeitos dos fármacos , Oryzias/fisiologia , Reflexo de Sobressalto/efeitos dos fármacos , Testes de Toxicidade Aguda , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Olho/efeitos dos fármacos , Olho/enzimologia , Natação , Poluentes Químicos da Água/toxicidade
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