sh.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
Combinatory effects of low concentrations of 17α-etinylestradiol and citalopram on non-reproductive behavior in adult zebrafish (Danio rerio)
Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.ORCID iD: 0000-0002-0856-9707
Örebro University.
Örebro University.
Show others and affiliations
2017 (English)In: Vol. 193, 9-17 p.Article in journal (Refereed) Published
Abstract [en]

Sewage treatment plant effluents contain a complex mixture of pharmaceuticals, personal care products and industrial chemicals, thus exposing aquatic organisms. Still, the consequences of exposure to combinations of different classes of drugs is largely unknown. In this study, we expose adult zebrafish (Danio rerio) males and females to low, environmentally relevant concentrations of the endocrine disrupting chemical 17α-ethinyl estradiol (EE2) and the selective serotonin re-uptake inhibitor (SSRI) citalopram, alone and in combination, and analyse three non-reproductive behaviours of importance for population fitness.

Two weeks exposure to 0.1 and 0.5 ng/LEE2 resulted in increased anxiety in males in the scototaxis (light/dark preference) test. Significantly longer latency periods before entering the white zone and fewer visits in the white zone were observed in males exposed to both 0.1 and 0.5 ng/LEE2 compared to unexposed males. No significant effects of citalopram alone (0.1 and 0.5 µg/L) were observed in the scototaxis test. The combined exposures (0.1 ng/L EE2 + 0.1 µg/L citalopram and 0.5 ng/L EE2 + 0.5 µg/L citalopram) resulted in abolishment of the anxiogenic effects of EE2, with significantly shorter latency period (low dose) and more transitions to white (high and low dose) than in fish exposed to EE2 alone. No significant effects of either EE2, citalopramor the combination of the two were observed in females. In the novel tank test, significantly more transitions to the upper half of the tank were observed in males exposed to 0.1 µg/L citalopram alone compared to unexposed males while males exposed to 0.1 ng/lEE2 had significantly shorter latency period to enter the upper half. Exposure to the combination of the two low concentrations did, however, result in a significantly longer latency and fewer transitions to upper half compared to both control, EE2- and citalopram-exposed males. These males also spent significantly less time in the upper half than the fish exposed to 0.1 ng/l EE2 or 0.1 µg/l citalopram alone. No significant effects on novel tank behaviour were observed in females or males exposed to the higher concentrations. In the shoaling test, males exposed to 0.1 µg/L citalopram and females exposed to 0.5 ng/l EE2 made significantly fewer transitions away from peers while males exposed to 0.1 µg/L citalopram + 0.1 ng/l EE2 performed significantly more transitions than the fish exposed to 0.1 µg/L citalopram alone.

In conclusion, this study shows that very low concentrations ofEE2, at or slightly above the predicted noeffect concentration (NOEC), affects anxiety in zebrafish males. Furthermore, citalopram, in spite of marginal effect of its own at such low levels, counteracts the response to EE2. This study represents an initial effort to understand the effects on water-living organisms of the cocktails of anthropogenic substances contaminating aquatic environments.

Place, publisher, year, edition, pages
2017. Vol. 193, 9-17 p.
National Category
Environmental Sciences
Research subject
Environmental Studies
Identifiers
URN: urn:nbn:se:sh:diva-32427DOI: 10.1016/j.aquatox.2017.10.001PubMedID: 29017090Scopus ID: 2-s2.0-85030678324OAI: oai:DiVA.org:sh-32427DiVA: diva2:1089335
Funder
Stockholm County Council, 806/3.1.1/2014The Foundation for Baltic and East European Studies, 1352/3.1.1/2015
Note

As manuscript in dissertation with title: Combinatory effects of low-dose 17alpha-etinyl estradiol and citalopram on behavior in adult zebrafish (Danio rerio)

Available from: 2017-04-19 Created: 2017-04-19 Last updated: 2017-10-16Bibliographically approved
In thesis
1. Selective serotonin re-uptake inhibitors in the environment: Effects of citalopram on fish behaviour
Open this publication in new window or tab >>Selective serotonin re-uptake inhibitors in the environment: Effects of citalopram on fish behaviour
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Selective serotonin re-uptake inhibitors (SSRIs) are a class of anxiolytic and anti-depressant drugs. SSRIs act on the evolutionarily ancient serotonergic system which is virtually identical throughout the vertebrate phylum. Serotonin is involved in a wide range of processes ranging from neuronal and craniofacial embryonic development to regulation of behaviour. However, SSRIs are also emerging pollutants, mainly entering the environment via sewage treatment plants. Since the serotonergic system is virtually identical in humans and other animals, exposed animals will be affected in similar ways as humans and suspicions are rising that ecologically important behaviours may be affected in subtle ways. Using the three-spined stickleback (Gasterosteus aculeatus) and zebrafish (Danio rerio) as model organisms, this thesis focuses on the behavioural effects of SSRIs in fish. The SSRI used throughout this thesis is citalopram, which has been found in fish in coastal areas of the Baltic Sea and other parts of the world.

Effects on behaviour were investigated using several different tests measuring stress response, feeding behaviour, aggression and locomotor activity. Anxiolytic effects of 0.1 μg/l, 1.5 μg/l 15 μg/l were investigated as well as effects of 0.15 μg/l and 1.5 μg/l on feeding behaviour. Because serotonin is involved in the development of the nervous system, the effects of developmental exposure to 1.5 μg/l was studied after 100 days of remediation. Finally, because SSRIs rarely occur alone in natural waters, the effects on zebrafish of citalopram in a cocktail scenario, with the anxiogenic compound 17α-ethinyl estradiol (EE2 ) was also investigated. Citalopram was found to have anxiolytic effects on the three-spined stickleback at 0.1 μg/l, 1.5 μg/l and 15 μg/l.

Citalopram also suppressed feeding behaviour within a week of exposure and at concentrations as low as 0.15 μg/l. Developmental exposure to 1.5 μg/l for 30 days was found to increase aggression and feeding behaviour and to reduce locomotor activity. The changes were persistent and remained in adult fish. In the cocktail scenario, citalopram in single-substance exposure had anxiolytic effects on one parameter in the novel tank test at 0.1 μg/l. Citalopram enhanced the anxiogenic effects of EE2 in the novel tank test, but in the scototaxis test citalopram appeared to counteract the effects of EE2. It is concluded that citalopram has the potential to affect behaviour in fish at concentrations that have been found in close proximity of sewage treatment plants.

Abstract [sv]

Det serotonerga systemet är i stort sett identiskt hos människor och övriga vertebrater. Serotonin är inblandat i ett stort antal kroppsliga funktioner, bland annat stressreaktioner, reglering av födobeteende och aggression. Vidare är serotonin med och reglerar nervsystemets tillväxt under embryonalutvecklingen. Selektiva serotoninåterupptagshämmare (SSRI) är en grupp antidepressiva och lugnande läkemedel vars användning har ökat snabbt på senare år då de är effektiva och har få allvarliga bieffekter. SSRI verkar på det serotonerga systemet, genom att blockera återupptaget av serotonin i den presynaptiska nervänden. SSRI har tilldragit sig en viss uppmärksamhet som potentiella miljöhot då de visats kunna påverka ekologiskt relevanta beteenden hos fisk och andra akvatiska organismer vid relativt låga koncentrationer i miljön samtidigt som de bryts ned dåligt i avloppsreningsverk. Avhandlingen fokuserar på ekologiskt relevanta beteendeeffekter av SSRI på fisk, med storspigg (Gasterosteus aculeatus) och zebrafisk (Danio rerio) som modellorganismer. Citalopram har använts som försökssubstans då det anses vara den SSRI som har minst antal sidoeffekter på till exempel det dopaminerga systemet. Citalopram förekommer i utloppsvatten från reningsverk i alla industrialiserade länder och har även hittats i abborre i Östersjön.

Effekter av exponering för SSRI har påvisats med hjälp av olika beteendetest. Skototaxi-test och novel tank diving test mäter stressresponsen genom att kvantifiera preferensen för närhet till botten och mörka omgivningar. Ätbeteende har mätts som antal utfall mot en matbit under en given tidsperiod och aggression har mätts genom att räkna antal bett mot en spegel. Anxiolytiska effekter undersöktes vid koncentrationer på 0,1 µg/l, 15 µg/l och 1,5 µg/l. Effekter på ätbeteende undersöktes vid 0,15 µg/l och 1,5 µg/l. Eftersom serotonin är inblandat i embryonalutvecklingen testades de beteendemässiga effekterna av exponering för 1,5 µg/l under utvecklingen. Då citalopram sällan förekommer ensamt i miljön testades ett cocktailscenario där zebrafisk samtidigt exponerades för citalopram och den anxiogena substansen 17α-etinylestradiol (EE2).

Citalopram befanns ha anxiolytisk verkan på storspigg samt undertrycka ätbeteendet. Effekter på ätbeteendet uppstod inom en vecka efter exponering och vid den minsta testade dosen vilken var 0,15 µg/l. Storspigg som exponerats under embryonalutvecklingen var mer aggressiva, hade lägre lokomotoraktivitetoch gjorde fler utfall mot mat då de testades 100 dagar efter att exponeringen avslutats. Samtidigt exponering för citalopram och den anxiogena substansen 17α-etinylestradiol (EE2) gav tvetydiga resultat. Citalopram ensamt hade ingen signifikant påverkan på beteendet i detta försök. I skototaxitestet motverkade citalopram den anxiogena effekten av EE2 medan det förstärkte den anxiogena effekten i novel tank. Sammanfattningsvis har citalopram effekter på ekologiskt relevanta beteenden hos fisk i koncentrationer som förekommer i ytvatten. Det har också permanenta effekter på beteende om exponeringen sker under embryonalutvecklingen. Dessa resultat gör det sannolikt att citalopram och andra SSRI har ekologiska effekter i påverkade vattendrag.

Place, publisher, year, edition, pages
Huddinge: Södertörns högskola, 2017. 63 p.
Series
Södertörn Doctoral Dissertations, ISSN 1652-7399 ; 137
Keyword
Citalopram, SSRI, stickleback, Baltic, behaviour, fish, feeding, anxiety, boldness, serotonin, development, Storspigg, serotonin, östersjön, SSRI, läkemedel, miljö, citalopram, ätbeteende, beteende, utveckling
National Category
Environmental Sciences
Research subject
Environmental Studies; Baltic and East European studies
Identifiers
urn:nbn:se:sh:diva-32422 (URN)978-91-87843-96-9 (ISBN)978-91-87843-97-6 (ISBN)
Public defence
2017-06-01, MA624, Alfred Nobels allé 7, Huddinge, 13:00 (English)
Opponent
Supervisors
Funder
Stockholm County Council, 806/3.1.1/2014The Foundation for Baltic and East European Studies, 1352/3.1.1/2015
Available from: 2017-05-10 Created: 2017-04-19 Last updated: 2017-09-25Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMedScopus

Search in DiVA

By author/editor
Porseryd, ToveKellner, MartinReyhanian, NasimVolkova, KristinaElabbas, LubnaOlsén, K. HåkanDinnétz, PatrikPorsch Hällström, Inger
By organisation
Environmental ScienceBiologySchool of Natural Sciences, Technology and Environmental Studies
Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 84 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