oru.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
17 alpha-Ethinyl estradiol affects anxiety and shoaling behavior in adult male zebra fish (Danio rerio)
Örebro University, School of Science and Technology. Södertörn university, Stockholm, Sweden.
Örebro University, School of Science and Technology. Södertörn university, Stockholm, Sweden.
Södertörn university, Stockholm, Sweden.
Södertörn university, Stockholm, Sweden.
Show others and affiliations
2011 (English)In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 105, no 1-2, p. 41-48Article in journal (Refereed) Published
Abstract [en]

Ethinyl estradiol is a potent endocrine disrupting compound in fish and ubiquitously present in the aquatic environment. In this study, we exposed adult zebra fish (Danio rerio) males to 0,5 or 25 ng Ethinyl estradiol/L for 14 days and analyzed the effects on non-reproductive behavior. Effects of treatment of the exposed males was shown by vitellogenin induction, while brain aromatase (CYP 19B) activity was not significantly altered. Both concentrations of Ethinyl estradiol significantly altered the behavior in the Novel tank test, where anxiety is determined as the tendency to stay at the bottom when introduced into an unfamiliar environment. The effects were, however, opposite for the two concentrations. Fish that were exposed to 5 ng/L had longer latency before upswim, fewer transitions to the upper half and shorter total time spent in the upper half compared with control fish, while 25 ng Ethinyl estradiol treatment resulted in shorter latency and more and longer visits to the upper half. The swimming activity of 25, but not 5 ng-exposed fish were slightly but significantly reduced, and these fish tended to spend a lot of time at the surface. We also studied the shoaling behavior as the tendency to leave a shoal of littermates trapped behind a Plexiglas barrier at one end of the test tank. The fish treated with Ethinyl estradiol had significantly longer latency before leaving shoal mates and left the shoal fewer times. Further, the fish exposed to 5 ng/L also spent significantly less time away from shoal than control fish. Fertilization frequency was higher in males exposed to 5 ng/L Ethinyl estradiol when compared with control males, while no spawning was observed after treatment with 25 ng/L The testes from both treatment groups contained a normal distribution of spermatogenesis stages, and no abnormality in testis morphology could be observed. In conclusion, we have observed effects on two behaviors not related to reproduction in zebra fish males after treatment with Ethinyl estradiol, adding to the ecological consequences of contamination of aquatic environments with estrogenic substances. (C) 2011 Elsevier B.V. All rights reserved.

Place, publisher, year, edition, pages
2011. Vol. 105, no 1-2, p. 41-48
National Category
Biological Sciences
Research subject
Biology
Identifiers
URN: urn:nbn:se:oru:diva-18647DOI: 10.1016/j.aquatox.2011.05.009ISI: 000294317500005OAI: oai:DiVA.org:oru-18647DiVA, id: diva2:444906
Available from: 2011-09-30 Created: 2011-09-29 Last updated: 2018-05-03Bibliographically approved
In thesis
1. Hitting the mark: studies of alterations in behaviour and fertility in ethinyl estradiol-exposed zebrafish and search related biomarkers
Open this publication in new window or tab >>Hitting the mark: studies of alterations in behaviour and fertility in ethinyl estradiol-exposed zebrafish and search related biomarkers
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In this thesis, we have analysed the effects of EE2 on non-reproductive behaviours and fertility. We have showed that two doses of EE2 in male adult short-term exposures evokes opposite behaviours in the novel tank test. A lower dose induced increased bottom-dwelling, a sign of increased anxiety and a higher dose increased surface-dwelling, which would likely expose themselves to predation in a natural environment. Increased shoaling was observed in both exposures, possibly affecting feeding and reproduction opportunities. Fertility analysis of these fish demonstrated a complete inhibition of spawning in the highest dose group. To investigate mechanisms behind the spawning failure, we examined expression levels of genes involved in zebrafish sex differentiation and maintenance of gonadal function. We found downregulated transcription levels of male-predominant genes, suggesting a demasculinization of the testes contributing to functional sterility in these fish. We have demonstrated that non-reproductive behaviour in zebrafish is highly sensitive to EE2 exposure during development. After exposing male and female zebrafish to low doses of EE2 followed by remediation in clean water until adulthood, the fish displayed increased anxiety and shoaling behaviour, demonstrating persistent effects of EE2. Furthermore, behavioural effects were transferred to their progeny. Decreased fertilisation success of the developmentally exposed fish was observed in both sexes when mated to untreated animals of the opposite sex. These fertility effects persisted although the fish had a long remediation period, implying likely reduced fitness of fish populations in aquatic environments. Based on our findings on non-reproductive behaviours and fertility, we performed RNAsequencing analysis of the brain and testes in order to investigate possible biological mechanisms behind the persistent effects. There is a need for biomarkers allowing detection of both reversible and irreversible effects in animals exposed to estrogenic substances, hopefully contributing to better risk assessments for EDCs. Results from RNA-sequencing would serve as a basis for continued studies in pursuit of potential biomarkers.

Place, publisher, year, edition, pages
Örebro: Örebro university, 2016. p. 55
Series
Örebro Studies in Biology, ISSN 1650-8793 ; 10
Series
Södertörn Doctoral Dissertations, ISSN 1652-7399 ; 115
Keywords
Endocrine disrupting compounds, 17α-ethinylestradiol, fertility, anxiety, behaviour, zebrafish, biomarkers, stress
National Category
Other Biological Topics
Research subject
Biology
Identifiers
urn:nbn:se:oru:diva-47393 (URN)978-91-7529-115-4 (ISBN)
Public defence
2016-02-25, Sal MA636, Södertörns högskola, Alfred Nobels allé 7, Huddinge, 13:00 (English)
Opponent
Supervisors
Available from: 2016-01-13 Created: 2016-01-13 Last updated: 2017-10-17Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Authority records BETA

Olsson, Per-Erik

Search in DiVA

By author/editor
Olsson, Per-Erik
By organisation
School of Science and Technology
In the same journal
Aquatic Toxicology
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 555 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf