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1.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33374934

RESUMO

DNA damage caused by exogenous or endogenous factors is a common challenge for developing fish embryos. DNA damage repair (DDR) pathways help organisms minimize adverse effects of DNA alterations. In terms of DNA repair mechanisms, sturgeons represent a particularly interesting model due to their exceptional genome plasticity. Sterlet (Acipenser ruthenus) is a relatively small species of sturgeon. The goal of this study was to assess the sensitivity of sterlet embryos to model genotoxicants (camptothecin, etoposide, and benzo[a]pyrene), and to assess DDR responses. We assessed the effects of genotoxicants on embryo survival, hatching rate, DNA fragmentation, gene expression, and phosphorylation of H2AX and ATM kinase. Exposure of sterlet embryos to 1 µM benzo[a]pyrene induced low levels of DNA damage accompanied by ATM phosphorylation and xpc gene expression. Conversely, 20 µM etoposide exposure induced DNA damage without activation of known DDR pathways. Effects of 10 nM camptothecin on embryo development were stage-specific, with early stages, before gastrulation, being most sensitive. Overall, this study provides foundational information for future investigation of sterlet DDR pathways.


Assuntos
Dano ao DNA , Reparo do DNA , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Peixes/genética , Animais , Benzo(a)pireno/toxicidade , Camptotecina/toxicidade , Ensaio Cometa , Fragmentação do DNA/efeitos dos fármacos , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Etoposídeo/toxicidade , Feminino , Peixes/embriologia , Masculino , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade
2.
Chemosphere ; 254: 126882, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957289

RESUMO

Methamphetamine, mainly consumed as an illicit drug, is a potent addictive psychostimulant that has been detected in surface water at concentrations ranging from nanograms to micrograms per litre, especially in Middle and East Europe. The aim of this study was to expose brown trout (Salmo trutta fario) to environmental (1 µg L-1) and higher (50 µg L-1) concentrations of methamphetamine for 35 days with a four-day depuration phase to assess the possible negative effects on fish health. Degenerative liver and heart alterations, similar to those described in mammals, were observed at both concentrations, although at different intensities. Apoptotic changes in hepatocytes, revealed by activated caspase-3, were found in exposed fish. The parent compound and a metabolite (amphetamine) were detected in fish tissues in both concentration groups, in the order of kidney > liver > brain > muscle > plasma. Bioconcentration factors ranged from 0.13 to 80. A therapeutic plasma concentration was reached for both compounds in the high-concentration treatment. This study indicates that chronic environmental concentrations of methamphetamine can lead to health issues in aquatic organisms.


Assuntos
Metanfetamina/toxicidade , Truta/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Europa (Continente) , Rim/patologia , Fígado/metabolismo , Truta/metabolismo
4.
Small ; 16(36): e2003303, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32700469

RESUMO

Nanotechnologies have reached maturity and market penetration that require nano-specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)-by-Design (SbD) concepts. This paper provides an overview of the state-of-the-art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re-thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science-based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.

5.
Biomolecules ; 10(2)2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979037

RESUMO

The lipid composition of sperm membranes is crucial for fertilization and differs among species. As the evolution of internal fertilization modes in fishes is not understood, a comparative study of the sperm lipid composition in freshwater representatives of externally and internally fertilizing fishes is needed for a better understanding of taxa-specific relationships between the lipid composition of the sperm membrane and the sperm physiology. The lipidomes of spermatozoa from stingray, a representative of cartilaginous fishes possessing internal fertilization, and sterlet, a representative of chondrostean fishes with external fertilization, have been studied by means of nuclear magnetic resonance (NMR), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), electrospray MS, gas chromatography-(GC) MS, and thin-layer chromatography (TLC). NMR experiments revealed higher cholesterol content and the presence of phosphatidylserine in stingray compared to sterlet sperm. Unknown MS signals could be assigned to different glycosphingolipids in sterlet (neutral glycosphingolipid Gal-Cer(d18:1/16:0)) and stingray (acidic glycosphingolipid sulpho-Gal-Cer(d18:1/16:0)). Free fatty acids in sterlet sperm indicate internal energy storage. GC-MS experiments indicated a significant amount of adrenic acid, but only a low amount of docosahexaenoic acid in stingray sperm. In a nutshell, this study provides novel data on sperm lipid composition for freshwater stingray and sterlet possessing different modes of fertilization.

6.
Ecotoxicol Environ Saf ; 188: 109912, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706240

RESUMO

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


Assuntos
Androstenos/toxicidade , Carpas/crescimento & desenvolvimento , Disruptores Endócrinos/toxicidade , Norpregnenos/toxicidade , Diferenciação Sexual/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Hepatopâncreas/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Diferenciação Sexual/genética
7.
Theriogenology ; 140: 33-43, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31425935

RESUMO

We report for the first time, a comparison of two approaches for artificially induced triploidy in zebrafish (Danio rerio) using cold shock and heat shock treatments. Of the two methods, heat shock treatment proved more effective with a triploid production rate of 100% in particular females. Subsequently, triploid zebrafish larvae were used as recipients for intraperitoneal transplantation of ovarian and testicular cells originating from vas:EGFP strain in order to verify their suitability for surrogate reproduction. Production of donor-derived sperm was achieved in 23% of testicular cell recipients and 16% of ovarian cell recipients, indicating the suitability of triploids as surrogate hosts for germ cell transplantation. Success of the transplantation was confirmed by positive GFP signal detected in gonads of dissected fish and stripped sperm. Germline transmission was confirmed by fertilization tests followed by PCR analysis of embryos with GFP specific primers. Reproductive success of germline chimera triploids evaluated as fertilization rate and progeny development was comparable to control groups.


Assuntos
Engenharia Genética/veterinária , Células Germinativas/transplante , Triploidia , Peixe-Zebra/genética , Animais , Cruzamento/métodos , Feminino , Citometria de Fluxo , Engenharia Genética/métodos , Masculino , Temperatura
8.
Animals (Basel) ; 9(3)2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30901855

RESUMO

To expand germ cell populations and provide a consistent supply for transplantation, we established basal culture conditions for sturgeon germ cells and subsequently increased their mitotic activity by eliminating gonad somatic cells, supplementing with growth factor, and replacing fetal bovine serum (FBS). The initial basal culture conditions were Leibovitz's L-15 medium (pH 8.0) supplemented with 5% FBS (p < 0.001) at 21 °C. Proliferation of germ cells was significantly enhanced and maintained for longer periods by elimination of gonad somatic cells and culture under feeder-cell free conditions, with addition of leukemia inhibitory factor and glial-cell-derived neurotrophic factor (p < 0.001). A serum-free culture medium improved germ cell proliferation compared to the L-15 with FBS (p < 0.05). Morphology remained similar to that of fresh germ cells for at least 40 d culture. Germline-specific gene expression analysis revealed no significant changes to germ cells before and after culture. Sterlet Acipenser ruthenus germ cells cultured more than 40 days showed development after transplant into Russian sturgeon Acipenser gueldenstaedtii. Polymerase chain reaction showed 33.3% of recipient gonads to contain sterlet cells after four months. This study developed optimal culture condition for sturgeon germ cells. Germ cells after 40 d culture developed in recipient gonads. This study provided useful information for culture of sturgeon germ cells.

9.
Cryobiology ; 87: 78-85, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30716303

RESUMO

Several experiments were conducted in order to develop an optimal protocol for slow-rate freezing (-1 °C/min) and short-term storage (-80 or 4 °C) of common carp ovarian tissue fragments with an emphasis on oogonial stem cells (OSCs). Dimethyl sulfoxide (Me2SO) with concentration of 1.5 M was identified as the best cryoprotectant in comparison to propylene glycol and methanol. When comparing supplementation of sugars (glucose, trehalose, sucrose) in different concentrations (0.1, 0.3, 0.5 M), glucose and trehalose in 0.3 M were identified as optimal. Short-term storage options for ovarian tissue pieces at -80 °C and 4 °C were tested as alternatives to cryopreservation and storage in liquid nitrogen. The presence of OSCs was confirmed by immunocytochemistry and viability after storage was determined by the trypan blue exclusion test. This study identified the optimal protocol for OSC cryopreservation using slow rate freezing resulting in ∼65% viability. The frozen/thawed OSCs were labelled by PKH-26 and transplanted into goldfish recipients. The success of the transplantation was confirmed by presence of fluorescent cells in the recipient gonad and later on by RT-PCR with carp dnd1 specific primers. The results of this study can facilitate long-term preservation of common carp germplasm which can be recovered in a surrogate recipient through interspecific germ cell transplantation.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Oogônios/fisiologia , Células-Tronco de Oogônios/fisiologia , Animais , Carpas , Sobrevivência Celular/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Feminino , Congelamento , Metanol/farmacologia , Oogônios/citologia , Ovário/citologia , Propilenoglicol/farmacologia , Sacarose/farmacologia , Trealose/farmacologia
10.
Sci Total Environ ; 663: 206-215, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30711587

RESUMO

High rates of progestins consumption in the form of active ingredients in women's oral contraceptives and other hormonal preparations may lead to their increased concentrations in aquatic environments and subsequent harmful effect on fish reproduction. The objective of the present study was to assess the effect of etonogestrel, a third-generation synthetic progestin, on the reproductive behavior, fertility, gonads histology, and secondary sexual characteristics of male and female Endler's guppies (Poecilia wingei). Fish were subjected for 34 days to two concentrations of etonogestrel, including one possibly environmentally relevant (3.2 ng L-1) and one sublethal (320 ng L-1) concentration. A mating behavior study was subsequently conducted and revealed that the treatment with etonogestrel significantly reduced mating frequency in the exposed fish compared to controls. All the exposed females were unable to reproduce. In addition, female fish exposed to the highest level of etonogestrel were masculinized, as their anal fins and body coloration showed patterns similar to those of male fish. Etonogestrel-exposed females also had fewer developed oocytes. In conclusion, the low etonogestrel concentration (3.2 ng L-1) led to a reduction of mating activity in males without effect on their reproductive success, but it completely inhibited reproduction in females. Exposure to etonogestrel clearly has more severe consequences for females than males.


Assuntos
Anticoncepcionais Femininos/efeitos adversos , Desogestrel/efeitos adversos , Poecilia/fisiologia , Reprodução/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Animais , Feminino , Fertilidade/efeitos dos fármacos , Gônadas/anatomia & histologia , Gônadas/efeitos dos fármacos , Masculino , Poecilia/anatomia & histologia , Caracteres Sexuais
11.
Micron ; 111: 19-27, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29859424

RESUMO

Detection of patterns of subcellular calcium distribution in the cardiovascular system can contribute to understanding its role in cardiac and blood function. The present study localized calcium in heart atrium, ventricle, and bulbus arteriosus as well as in erythrocytes of zebrafish Danio rerio using an oxalate-pyroantimonate technique combined with transmission electron microscopy. Intracellular calcium stores were detected in caveolae, mitochondria, and the nuclei of several zebrafish cardiac cell types. Melanin pigmentation containing calcium stores was detected in the pericardial cavity. Melanin might be an extracellular source of calcium for heart beating and/or a lubricant to prevent friction during beating process. Calcium deposits were also detected in the plasma membrane, cytoplasm and nucleus of erythrocytes as well as in blood plasma. Possible exchange of calcium between erythrocytes and blood plasma was observed. Interactions of such calcium stores and possible contribution of extracellular calcium stores such as melanin pigmentation to supply calcium for vital functions of heart cells should be addressed in future studies.


Assuntos
Cálcio/análise , Eritrócitos/metabolismo , Átrios do Coração/citologia , Ventrículos do Coração/citologia , Miócitos Cardíacos/metabolismo , Peixe-Zebra/fisiologia , Animais , Cavéolas/metabolismo , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Melaninas/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo
12.
Nanomaterials (Basel) ; 8(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596351

RESUMO

Nanotechnology is closely related to the tailored manufacturing of nanomaterials for a huge variety of applications. However, such applications with newly developed materials are also a reason for concern. The DaNa2.0 project provides information and support for these issues on the web in condensed and easy-to-understand wording. Thus, a key challenge in the field of advanced materials safety research is access to correct and reliable studies and validated results. For nanomaterials, there is currently a continuously increasing amount of publications on toxicological issues, but criteria to evaluate the quality of these studies are necessary to use them e.g., for regulatory purposes. DaNa2.0 discusses scientific results regarding 26 nanomaterials based on actual literature that has been selected after careful evaluation following a literature criteria checklist. This checklist is publicly available, along with a selection of standardized operating protocols (SOPs) established by different projects. The spectrum of information is rounded off by further articles concerning basics or crosscutting topics in nanosafety research. This article is intended to give an overview on DaNa2.0 activities to support reliable toxicity testing and science communication alike.

13.
Chemosphere ; 159: 10-22, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27268790

RESUMO

The aim of this study was to characterize biomarker responses, haematological profiles, structural changes and uptake in juvenile rainbow trout exposed to clotrimazole (CLO) at three concentrations (0.01 - [lowest environmentally relevant concentration], 1.0 [highest environmentally relevant concentration] and 10 µg L(-1)) in a semi-static system over a period of 42 days. Antioxidant defence enzymes, which responded to CLO exposure, changed the oxidative stress status of cells, but no differences were observed in lipid peroxidation. Clotrimazole triggered a biphasic response of CYP3A-like activity in liver microsomes, which may indicate a detoxification process in the liver. Histopathological alterations were most pronounced in kidneys and testes in the group exposed to 10 µg L(-1). Structural changes in the kidney included tubulonephrosis and hyaline droplet degeneration in the tubular epithelial cells. The relative proportions of germ cells in testes were changed: The number of spermatozoa was reduced, and the spermatogonia and spermatocytes were increased. The highest CLO concentration was detected in fish liver (3710 ng per gram wet tissue) and kidney (4280 ng per gram wet tissue). Depuration half-life was estimated to be 72, 159, and 682 h in liver, muscle, and kidney, respectively. Taken together, these results provide valuable toxicological data on the effects of CLO on aquatic non-target organisms, which could be useful for further understanding of the potential risks in the real aquatic environment.


Assuntos
Clotrimazol/toxicidade , Oncorhynchus mykiss , Poluentes Químicos da Água/toxicidade , Animais , Clotrimazol/farmacocinética , Meia-Vida , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Masculino , Microssomos Hepáticos/metabolismo , Músculos/metabolismo , Oncorhynchus mykiss/anatomia & histologia , Oncorhynchus mykiss/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Contagem de Espermatozoides , Espermatozoides/citologia , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia , Poluentes Químicos da Água/farmacocinética
14.
Chemosphere ; 157: 57-64, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27208646

RESUMO

Diltiazem is a pharmaceutical belonging to a group of calcium channel blockers (CCB) that is widely used in the treatment of angina pectoris and hypertension. The objective of the present study was to assess the effect of diltiazem on rainbow trout (Oncorhynchus mykiss). Juvenile trout were exposed for 21 and 42 days to three nominal concentrations of diltiazem: 0.03 µg L(-1) (environmentally relevant concentration), 3 µg L(-1), and 30 µg L(-1) (sub-lethal concentrations). The number of mature neutrophilic granulocytes was significantly increased by 450 and 400% in fish exposed to 3 µg L(-1) and 30 µg L(-1) diltiazem compared to the control, respectively. Antioxidant enzyme activity was affected in liver and gills of fish exposed to all tested concentrations of diltiazem but the changes were mostly transient and not concentration dependent. Creatine kinase activity was markedly increased (ranging from 520 to 845%) at all tested diltiazem concentrations at the end of the exposure indicating muscle and/or kidney damage. The highest concentration was associated with histological changes in heart, liver, and kidney. These alterations can be attributed to the effects of diltiazem on the cardiovascular system, similar to those observed in the human body, as well as to its metabolism. At the environmentally relevant concentration, diltiazem was found to induce some alterations in the blood, gills, and liver of fish, indicating its potential for adverse effects on non-target organisms in the aquatic environment.


Assuntos
Diltiazem/farmacologia , Oncorhynchus mykiss/metabolismo , Poluentes Químicos da Água/farmacologia , Animais , Bloqueadores dos Canais de Cálcio , Relação Dose-Resposta a Droga , Brânquias/enzimologia , Brânquias/metabolismo , Rim/metabolismo , Rim/patologia , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Miocárdio/patologia , Oxirredutases/análise , Fatores de Tempo , Poluentes Químicos da Água/farmacocinética
15.
Rapid Commun Mass Spectrom ; 30(9): 1153-62, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-27060844

RESUMO

RATIONALE: Diltiazem, a calcium channel blocker drug, is widespread in the environment because of its incomplete elimination during water treatment. It can cause negative effects on aquatic organisms; thus, a rapid and sensitive liquid chromatography/mass spectrometry (LC/MS) method to detect its presence was developed. Our approach is based on accurate mass measurements using a hybrid quadrupole-orbital trap mass spectrometer that was used to measure diltiazem and its metabolites in fish tissue. METHODS: Blood plasma, muscle, liver, and kidney tissues of rainbow trout (Oncorhynchus mykiss), exposed for 42 days to 30 µg L(-1) diltiazem, were used for the method development. No metabolite standards were required to identify the diltiazem biotransformation products in the fish tissue. RESULTS: Overall, 17 phase I diltiazem metabolites (including isomeric forms) were detected and tentatively identified using the MassFrontier spectral interpretation software. A semi-quantitative approach was used for organ-dependent comparison of the metabolite concentrations. CONCLUSIONS: These data increase our understanding about diltiazem and its metabolites in aquatic organisms, such as fish. These encompass desmethylation, desacetylation and hydroxylation as well as their combinations. This study represents the first report of the complex diltiazem phase I metabolic pathways in fish.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/metabolismo , Diltiazem/química , Diltiazem/metabolismo , Peixes/metabolismo , Espectrometria de Massas/métodos , Animais , Cromatografia Líquida/métodos , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Estrutura Molecular , Músculos/química , Músculos/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
16.
Dis Aquat Organ ; 118(3): 185-94, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27025306

RESUMO

Histopathological alterations in the heart are often reported in fish as a result of exposure to a variety of chemical compounds. However, researchers presently lack a standardized method for the evaluation of histopathological alterations in the cardiovascular system of fish and the calculation of an 'organ index'. Therefore, we designed a method for a standardized assessment and evaluation of histopathological alterations in the heart of fish. As a model species, we used rainbow trout Oncorhynchus mykiss, but the protocol was also successfully applied to other fish species belonging to different taxonomic orders. To test the protocol, we re-evaluated sections of atenolol-exposed and unexposed rainbow trout obtained in a previous study. The results were in accordance with those previously published, demonstrating the applicability of the protocol. The protocol provides a universal method for the comparative evaluation of histopathological changes in the heart of fish.


Assuntos
Doenças dos Peixes/patologia , Cardiopatias/veterinária , Oncorhynchus mykiss , Animais , Doenças dos Peixes/classificação , Coração/anatomia & histologia , Cardiopatias/patologia , Miocárdio/patologia
17.
Chemosphere ; 144: 154-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26356646

RESUMO

Diltiazem is a human therapeutic drug and a member of the group of calcium channel blockers having widespread use in the treatment of angina pectoris and hypertension. The objective of the present study was to assess the bioconcentration, metabolism, and half-life time of diltiazem in rainbow trout Oncorhynchus mykiss. Juvenile trout were exposed for 21 and 42 days to three nominal concentrations of diltiazem: 0.03 µg L(-1) (environmentally relevant concentration), 3 µg L(-1), and 30 µg L(-1) (sub-lethal concentrations). The bioconcentration factor (BCF) of diltiazem was relatively low (0.5-194) in analysed tissues, following the order kidney > liver > muscle > blood plasma. The half-life of diltiazem in liver, kidney, and muscle was 1.5 h, 6.2 h, and 49 h, respectively. The rate of metabolism for diltiazem in liver, kidney, muscle, and blood plasma was estimated to be 85 ± 9%, 64 ± 14%, 46 ± 6%, and 41 ± 8%, respectively. Eight diltiazem metabolites were detected. The presence of desmethyl diltiazem (M1), desacetyl diltiazem (M2), and desacetyl desmethyl diltiazem (M3) suggests that rainbow trout metabolize diltiazem mainly via desmethylation and desacetylation, similar to mammals. In addition, diltiazem undergoes hydroxylation in fish. At environmentally relevant concentrations, diltiazem and its metabolites were identified in liver and kidney, indicating the potential for uptake and metabolism in non-target organisms in the aquatic environment.


Assuntos
Diltiazem/farmacocinética , Oncorhynchus mykiss/metabolismo , Poluentes Químicos da Água/farmacocinética , Animais , Diltiazem/sangue , Meia-Vida , Rim/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Poluentes Químicos da Água/sangue
18.
Sci Total Environ ; 497-498: 209-218, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25129157

RESUMO

Atenolol is a highly prescribed anti-hypertensive pharmaceutical and a member of the group of ß-blockers. It has been detected at concentrations ranging from ng L(-1) to low µg L(-1) in waste and surface waters. The present study aimed to assess the sub-lethal effects of atenolol on rainbow trout (Oncorhynchus mykiss) and to determine its tissue-specific bioconcentration. Juvenile rainbow trout were exposed for 21 and 42 days to three concentration levels of atenolol (1 µg L(-1) - environmentally relevant concentration, 10 µg L(-1), and 1000 µg L(-1)). The fish exposed to 1 µg L(-1) atenolol exhibited a higher lactate content in the blood plasma and a reduced haemoglobin content compared with the control. The results show that exposure to atenolol at concentrations greater than or equal to 10 µg L(-1) significantly reduces both the haematocrit value and the glucose concentration in the blood plasma. The activities of the studied antioxidant enzymes (catalase and superoxide dismutase) were not significantly affected by atenolol exposure, and only the highest tested concentration of atenolol significantly reduced the activity of glutathione reductase. The activities of selected CYP450 enzymes were not affected by atenolol exposure. The histological changes indicate that atenolol has an effect on the vascular system, as evidenced by the observed liver congestion and changes in the pericardium and myocardium. Atenolol was found to have a very low bioconcentration factor (the highest value found was 0.27). The bioconcentration levels followed the order liver>kidney>muscle. The concentration of atenolol in the blood plasma was below the limit of quantification (2.0 ng g(-1)). The bioconcentration factors and the activities of selected CYP450 enzymes suggest that atenolol is not metabolised in the liver and may be excreted unchanged.


Assuntos
Atenolol/toxicidade , Oncorhynchus mykiss/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Anti-Hipertensivos/metabolismo , Atenolol/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
19.
Neuro Endocrinol Lett ; 34 Suppl 2: 37-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24362091

RESUMO

OBJECTIVES: The aim of this study was to assess the effect of pesticide Fury 10 EW, containing zeta-cypermethrin 100 g.l-1, on common carp (Cyprinus carpio L.). DESIGN: The toxicity tests were performed on common carp according to OECD 203 methodologies. The common carp were exposed to Fury 10 EW at concentrations, 5, 7, 10, 50 and 100 µg.l-1 for 96 h and compared to common carp in a non-treated control group. Acute toxicity tests were detected value 96hLC50=13.8 µg.l-1. On the basis of the results was assessed the effect on the hematological profile, oxidative stress parameters, and antioxidants biomarkers in tissues, in another acute test. RESULTS: The observed 96hLC50 value of Fury 10 EW was 13.8 µg.l-1. A significantly lower large lymphocyte and monocyte count, and a significantly greater number of segmented eosinophil granulocyte and higher hematocrit was found in the pesticide-exposed common carp compared to controls. Oxidative damage was not detected in the experimental common carp, however there were significant differences from control in superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in tissue after acute exposure to 13.8 µg.l-1 Fury 10 EW. CONCLUSIONS: Zeta-cypermethrin as Fury 10 EW was classified as a substance highly toxic to fish. The hematological profile well oxidative stress parameters and antioxidant defensive systems provide important information about the internal environment of organisms. There is a lack of experimental results about the effects of zeta-cypermethrin on fish in the literature.


Assuntos
Carpas/fisiologia , Inseticidas/toxicidade , Piretrinas/toxicidade , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda
20.
Ecotoxicol Environ Saf ; 96: 41-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23906701

RESUMO

UV filters belong to a group of compounds that are used by humans and are present in municipal waste-waters, effluents from sewage treatment plants and surface waters. Current information regarding UV filters and their effects on fish is limited. In this study, the occurrence of three commonly used UV filters - 2-phenylbenzimidazole-5-sulfonic acid (PBSA), 2-hydroxy-4-methoxybenzophenone (benzophenone-3, BP-3) and 5-benzoyl-4-hydroxy-2-methoxy-benzenesulfonic acid (benzophenone-4, BP-4) - in South Bohemia (Czech Republic) surface waters is presented. PBSA concentrations (up to 13µgL(-1)) were significantly greater than BP-3 or BP-4 concentrations (up to 620 and 390ngL(-1), respectively). On the basis of these results, PBSA was selected for use in a toxicity test utilizing the common model organism rainbow trout (Oncorhynchus mykiss). Fish were exposed to three concentrations of PBSA (1, 10 and 1000µgL(-1)) for 21 and 42 days. The PBSA concentrations in the fish plasma, liver and kidneys were elevated after 21 and 42 days of exposure. PBSA increased activity of certain P450 cytochromes. Exposure to PBSA also changed various biochemical parameters and enzyme activities in the fish plasma. However, no pathological changes were obvious in the liver or gonads.


Assuntos
Benzimidazóis/toxicidade , Oncorhynchus mykiss/fisiologia , Ácidos Sulfônicos/toxicidade , Protetores Solares/análise , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Água/química , Animais , Benzimidazóis/análise , Citocromos/metabolismo , República Tcheca , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácidos Sulfônicos/análise , Testes de Toxicidade Crônica
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