title: Danio rerio embryos on Prozac - Effects on the detoxification mechanism and embryo development.
abstract: In the past decade the presence of psychopharmaceuticals, including fluoxetine (FLU), in the aquatic environment has been associated with the increasing trend in human consumption of these substances. Aquatic organisms are usually exposed to chronic low doses and, therefore, risk assessments should evaluate the effects of these compounds in non-target organisms. Teleost fish possess an array of active defence mechanisms to cope with the deleterious effects of xenobiotics. These include ABC transporters, phase I and II of cellular detoxification and oxidative stress enzymes. Hence, the present study aimed at characterising the effect of FLU on embryo development of the model teleost zebrafish (Danio rerio) concomitantly with changes in the detoxification mechanisms during early developmental phases. Embryos were exposed to different concentrations of FLU (0.0015, 0.05, 0.1, 0.5 and 0.8μM) for 80hours post fertilization. Development was screened and the impact in the transcription of key genes, i.e., abcb4, abcc1, abcc2, abcg2, cyp1a, cyp3a65, gst, sod, cat, ahr, pxr, pparα, pparβ, pparγ, rxraa, rxrab, rxrbb, rxrga, rxrgb, raraa, rarab, rarga evaluated. In addition, accumulation assays were performed to measure the activity of ABC proteins and antioxidant enzymes (CAT and Cu/ZnSOD) after exposure to FLU. Embryo development was disrupted at the lowest FLU concentration tested (0.0015μM), which is in the range of concentrations found in WWTP effluents. Embryos exposed to higher concentrations of FLU decreased Cu/Zn SOD, and increased CAT (0.0015 and 0.5μM) enzymatic activity. Exposure to higher concentrations of FLU decreased the expression of most genes belonging to the detoxification system and upregulated cat at 0.0015μM of FLU. Most of the tested concentrations downregulated pparα, pparβ, pparγ, and raraa, rxraa, rxrab, rxrbb rxrgb and ahr gene expression while pxr was significantly up regulated at all tested concentrations. In conclusion, this study shows that FLU can impact zebrafish embryo development, at concentrations found in effluents of WWTPs, concomitantly with changes in antioxidant enzymes, and the transcription of key genes involved in detoxification and development. These finding raises additional concerns supporting the need to monitor the presence of this compound in aquatic reservoirs.
authors: CIIMAR/CIMAR-Interdisciplinary Centre of Marine and Environmental Research, Coastal and Marine Environmental Toxicology Lab, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; ICBAS/UP-Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal. Electronic address: vfpmc83@gmail.com.
authors: V
authors: V
authors: Cunha
authors: CIIMAR/CIMAR-Interdisciplinary Centre of Marine and Environmental Research, Coastal and Marine Environmental Toxicology Lab, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; ICBAS/UP-Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors: P
authors: P
authors: Rodrigues
authors: CIIMAR/CIMAR-Interdisciplinary Centre of Marine and Environmental Research, Coastal and Marine Environmental Toxicology Lab, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; FCUP-Dept of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
authors: M M
authors: MM
authors: Santos
authors: ICBAS/UP-Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; I3S-Institute for Research and Innovation in Health, University of Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC, Institute for Molecular and Cell Biology, Porto, Portugal.
authors: P
authors: P
authors: Moradas-Ferreira
authors: CIIMAR/CIMAR-Interdisciplinary Centre of Marine and Environmental Research, Coastal and Marine Environmental Toxicology Lab, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; School of Marine Studies, Faculty of Science, Techonology and Environment, The University of South Pacific, Laucala Bay Road, Suva, Fiji Islands.
authors: M
authors: M
authors: Ferreira
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000378:metabolism; D047108:Embryonic Development / Q000187:drug effects*; D005473:Fluoxetine / Q000633:toxicity*; D006801:Humans; D000089762:Multidrug Resistance-Associated Protein 2; D018384:Oxidative Stress / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015262:Xenobiotics / Q000633:toxicity; D015027:Zebrafish / Q000254:growth & development / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C000715087:ABCC2 protein, human; D018528:ATP-Binding Cassette Transporters; D000089762:Multidrug Resistance-Associated Protein 2; D014874:Water Pollutants, Chemical; D015262:Xenobiotics; D029961:Zebrafish Proteins; D005473:Fluoxetine; D002374:Catalase; D013482:Superoxide Dismutase
keywords: ABC transporters; Antioxidant enzymes; Fluoxetine; Nuclear receptors; Phase I and II; Zebrafish embryos