| 1. |
- Albertsson, Eva, 1979, et al.
(författare)
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Induction of hepatic carbonyl reductase/20beta-hydroxysteroid dehydrogenase mRNA in rainbow trout downstream from sewage treatment works--possible roles of aryl hydrocarbon receptor agonists and oxidative stress.
- 2010
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Ingår i: Aquatic toxicology (Amsterdam, Netherlands). - : Elsevier BV. - 1879-1514 .- 0166-445X. ; 97:3, s. 243-9
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Tidskriftsartikel (refereegranskat)abstract
- Carbonyl reductase/20beta-hydroxysteroid dehydrogenase (CR/20beta-HSD) serves both as a key enzyme in the gonadal synthesis of maturing-inducing hormone in salmonids, and as an enzyme protecting against certain reactive oxygen species. We have previously shown that mRNA of the hepatic CR/20beta-HSD B isoform is increased in rainbow trout caged downstream from a Swedish sewage treatment plant. Here, we report an increase of both the A as well as B form in fish kept downstream from a second sewage treatment plant. The two mRNAs were also induced in fish hepatoma cells in vitro after exposure to effluent extract. This indicates that the effects observed in vivo could be a direct effect on the liver, i.e. the mRNA induction does not require a signal from any other organ. When fish were exposed in vivo to several effluents treated with more advanced methods (ozone, moving bed biofilm reactor or membrane bioreactor) the expression of hepatic mRNA CR/20beta-HSD A and B was significantly reduced. Their abundance did not parallel the reduction of estrogen-responsive transcripts, in agreement with our previous observations that ethinylestradiol is not a potent inducer. Treatment with norethisterone, methyltestosterone or hydrocortisone in vivo did not induce the hepatic CR/20beta-HSD A and B mRNA expression. In contrast, both isoforms were markedly induced by the aryl hydrocarbon receptor agonist beta-naphthoflavone as well as by the pro-oxidant herbicide paraquat. We hypothesize that the induction of CR/20beta-HSD A and B by sewage effluents could be due to anthropogenic contaminants stimulating the aryl hydrocarbon receptor and/or causing oxidative stress.
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| 2. |
- Carney Almroth, Bethanie, 1974, et al.
(författare)
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Early-age changes in oxidative stress in brown trout, Salmo trutta
- 2010
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Ingår i: COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY. - 1096-4959. ; 155:4, s. 442-448
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Tidskriftsartikel (refereegranskat)abstract
- Fish are often used as models for studies investigating the ability of xenobiotics to induce oxidative stress, though age or developmental stage of the individuals studied has been given little attention. Oxidative stress in other organisms is associated with aging as well as with periods of rapid growth, which occurs in young brown trout. We measured protein carbonyls, 20S proteosome activity and glutathione (GSH) levels in farmed Salmo trutta in four different age groups from 5 months to 3 years. We found an increase in protein carbonyls and a decrease in 20S proteosome activity in both brain and liver tissues of the fish with increasing size and age. Total GSH levels in liver tissue declined as fish aged and the GSSG:GSH ratio increased. Five month and 1 year old trout were treated with paraquat (PQ) to induce oxidative stress. Five month old fish showed no changes in the measured parameters while 1 year old fish had both an increase in protein carbonylation in liver tissue and a decrease in 20S proteosome activity in brain tissue. These results indicate that oxidative stress biomarkers are affected by age or rapid growth in brown trout, and that individuals of different ages respond differently to oxidative stress induced by PQ.
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| 3. |
- Cuklev, Filip, 1981, et al.
(författare)
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Diclofenac in fish : blood plasma levels similar to human therapeutic levels affect global hepatic gene expression
- 2011
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Ingår i: Environmental Toxicology and Chemistry. - New York : Pergamon. - 0730-7268 .- 1552-8618. ; 30:9, s. 2126-2134
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Tidskriftsartikel (refereegranskat)abstract
- Diclofenac is a non-steroidal anti-inflammatory drug frequently found in the aquatic environment. Previous studies have reported histological changes in the liver, kidney and gills of fish at concentrations similar to those measured in treated sewage effluents (approximately 1 µg/L). Analyses or predictions of blood plasma levels in fish allow a direct comparison with human therapeutic plasma levels, and may therefore be used to indicate a risk for pharmacological effects in fish. To relate internal exposure to a pharmacological interaction we investigated global hepatic gene expression together with bioconcentration in blood plasma and liver of rainbow trout (Oncorhynchus mykiss) exposed to waterborne diclofenac. At the highest exposure concentration (81.5 µg/L) the fish plasma concentration reached approximately 88% of the human therapeutic levels (C(max) ) after two weeks. Using an oligonucleotide microarray followed by quantitative PCR we found extensive effects on hepatic gene expression at this concentration, and some genes were found to be regulated down to the lowest concentration tested (1.6 µg/L) corresponding to approximately 1.5% of the human C(max) . Thus, at concentrations detected in European surface waters, diclofenac can affect the expression of multiple genes in exposed fish. Functional analysis of differentially expressed genes revealed effects on biological processes such as inflammation and immune response, in agreement with the mode of action of diclofenac in mammals. In contrast to some previously reported results, the bioconcentration factor was found to be stable (4.02 ± 0.75 for blood plasma and 2.54 ± 0.36 for liver) regardless of the water concentration. Environ. Toxicol. Chem. © 2011 SETAC.
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| 4. |
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| 5. |
- Hanson, Niklas, 1976, et al.
(författare)
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Spatial and annual variation to define the normal range of biological endpoints: an example with biomarkers in perch
- 2010
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Ingår i: Environmental Toxicology and Chemistry. - 0730-7268. ; 29:11, s. 2616-2624
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Tidskriftsartikel (refereegranskat)abstract
- A signal from a biological endpoint can be considered evidence of environmental impact only if it is known that similar signals are unlikely to occur naturally. Using multiple reference sites, the normal range can be estimated. This can be defined as the span that includes 95% of the reference sites. If an investigated site is outside this range, it is interpreted as evidence of impact. The choice of reference sites is thus important for the outcome of the study. Here, biomarker levels in perch (Perca fluviatilis) at a potentially impacted site were compared to different types of reference data. The potentially impacted site was located close to a densely populated area. Four reference sites were located in relatively undisturbed areas on the Swedish Baltic coast. Furthermore, historical data from one of the reference sites were included. The present study showed that multiple reference sites are needed to avoid the risk of interpreting natural variation as impact. The number of reference sites needed depends on the desired level of statistical power. An alternative to multiple reference sites may be to use historical data to estimate the natural variation. However, historical data can include temporal variation due to factors that may not be relevant for the hypothesis that is tested, e.g., climatic variation or changed background levels of pollution.
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| 6. |
- Hedman, JE, et al.
(författare)
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Eelpout (Zoarces viviparus) in marine environmental monitoring
- 2011
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Ingår i: MARINE POLLUTION BULLETIN. - 0025-326X. ; 62:10, s. 2015-2029
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Forskningsöversikt (refereegranskat)abstract
- The implementation of the EU Marine Strategy Framework Directive necessitates the development of common criteria and methodological standards for marineenvironmentalmonitoring and assessment across Europe. Eelpout (Zoarcesviviparus) is proposed as a key indicator organism in the Baltic and North Sea regions. This benthic fish species is widely used in ecotoxicological studies and as a bioindicator of local pollution due to its stationary behavior. Eelpout is included in the environmentalmonitoring program of several Baltic States, covering both chemical and biological effects measurements, and samples have been archived in environmental specimen banks for >15 years. A method for evaluating the frequency of larval aberrations has been suggested as a standardized assessment tool. The large scientific knowledge-base and considerable experience of long-term chemical and biological effects monitoring and specimen banking, make eelpout a suitable species for the assessment of Good Environmental Status in the Baltic and North Seas.
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| 7. |
- Holmberg, Anna, 1974, et al.
(författare)
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Does waterborne citalopram affect the aggressive and sexual behaviour of rainbow trout and guppy?
- 2011
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Ingår i: Journal of hazardous materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 187:1-3, s. 596-9
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Tidskriftsartikel (refereegranskat)abstract
- Citalopram is one of several selective serotonin reuptake inhibitors (SSRIs) commonly found in treated sewage effluents. Accordingly, there are concerns about possible adverse effects of SSRIs on aquatic organisms, particularly behavioural effects similar to those associated with SSRI use in humans. Rainbow trout fry and adult male guppies were therefore exposed to waterborne citalopram, ranging from environmentally relevant to high concentrations (1, 10, 100 μg/L) for 3-7 days. Under these experimental conditions citalopram does not appear to cause significant effects on aggression in rainbow trout fry or on sexual behaviour in male guppies. This may be explained by a relatively low uptake of citalopram from water to fish.
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| 8. |
- Larsson, Åke, 1944, et al.
(författare)
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Kustfisk - hälsa
- 2010
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Ingår i: HAVET 2010. - 1654-6741.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 9. |
- Larsson, Åke, 1944, et al.
(författare)
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Kustfisk - hälsa
- 2011
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Ingår i: HAVET - Om miljötillståndet i svenska havsområden. - 1654-6741. ; år 2011
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 10. |
- Larsson, Åke, 1944, et al.
(författare)
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Kustfisken - alltmer påverkad av miljögifter
- 2011
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Ingår i: HAVET 2011 - Om miljötillståndet i svenska havsområden. - 1654-6741. ; år 2011, s. 74-79
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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