Depressing antidepressant: Fluoxetine affects serotonin neurons causing adverse reproductive responses in Daphnia magna
2016 (English)In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 50, no 11, 6000-6007 p.Article in journal (Refereed) Published
Selective serotonin reuptake inhibitors (SSRIs) are widely used antidepressants. As endocrine disruptive contaminants in the environment, SSRIs affect reproduction in aquatic organisms. In the water flea Daphnia magna, SSRIs increase offspring production in a food ration-dependent manner. At limiting food conditions, females exposed to SSRIs produce more but smaller offspring, which is a maladaptive life-history strategy. We asked whether increased serotonin levels in newly identified serotonin-neurons in the Daphnia brain mediate these effects. We provide strong evidence that exogenous SSRI fluoxetine selectively increases serotonin-immunoreactivity in identified brain neurons under limiting food conditions thereby leading to maladaptive offspring production. Fluoxetine increases serotonin-immunoreactivity at low food conditions to similar maximal levels as observed under high food conditions and concomitantly enhances offspring production. Sublethal amounts of the neurotoxin 5,7-dihydroxytryptamine known to specifically ablate serotonin-neurons markedly decrease serotonin-immunoreactivity and offspring production, strongly supporting the effect to be serotonin-specific by reversing the reproductive phenotype attained under fluoxetine. Thus, SSRIs impair serotonin-regulation of reproductive investment in a planktonic key organism causing inappropriately increased reproduction with potentially severe ecological impact.
Place, publisher, year, edition, pages
2016. Vol. 50, no 11, 6000-6007 p.
Selective serotonin-reuptake inhibitor, serotonin neurons, reproduction, Daphnia magna, freshwater ecotoxicology
Research subject Ecotoxicology
IdentifiersURN: urn:nbn:se:su:diva-129850DOI: 10.1021/acs.est.6b00826PubMedID: 27128505OAI: oai:DiVA.org:su-129850DiVA: diva2:925453
FunderCarl Tryggers foundation , CTS 07:78