Corticosteroid Fludrocortisone Acetate Targets Multiple End Points in Zebrafish (Danio rerio) at Low Concentrations.
Synthetic corticosteroids may pose an environmental risk to fish. Here, we describe multiend point responses of adult zebrafish (8 months old) upon 21-day exposure to a commonly prescribed corticosteroid, fludrocortisone acetate (FLU), at concentrations between 0.006 and 42 μg/L. No remarkable reproductive impacts were observed, while physiological effects, including plasma glucose level and blood leukocyte numbers were significant altered even at 42 ng/L. Ovary parameters and transcriptional analysis of hypothalamic-pituitary-gonadal-liver axis revealed negligible effects. Significant alterations of the circadian rhythm network were observed in the zebrafish brain. Transcripts of several biomarker genes, including per1a and nr1d1, displayed strong transcriptional changes, which occurred at environmental relevant concentrations of 6 and 42 ng/L FLU. Importantly, the development and behavior of F1 embryos were significant changed. Heartbeat, hatching success and swimming behavior of F1 embryos were all increased even at 6 and 42 ng/L. All effects were further confirmed by exposure of eleuthero-embryos. Significant transcriptional changes of biomarker genes involved in gluconeogenesis, immune response and circadian rhythm in eleuthero-embryos confirmed the observations in adult fish. Hatching success, heartbeat, and swimming activity were increased at 81 ng/L and higher, as with F1 embryos. These results provide novel insights into the understanding of potential environmental risks of corticosteroids.
School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, CH-4132 Muttenz, Switzerland.
Yanbin
Y
Zhao
School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, CH-4132 Muttenz, Switzerland.
Kun
K
Zhang
School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, CH-4132 Muttenz, Switzerland.|Institute of Biogeochemistry and Pollution Dynamics, Department of Environmental System Sciences, Swiss Federal Institute of Technology (ETH Zürich) , CH-8092 Zürich, Switzerland.
Karl
K
Fent
D000305:Adrenal Cortex Hormones / Q000378:metabolism; D000818:Animals; D004703:Endocrine System / Q000378:metabolism; D005260:Female; D005438:Fludrocortisone / Q000031:analogs & derivatives* / Q000378:metabolism / Q000633:toxicity; D010053:Ovary; D012098:Reproduction / Q000187:drug effects; D015027:Zebrafish / Q000378:metabolism
D000305:Adrenal Cortex Hormones; D005438:Fludrocortisone; C034635:fludrocortisone acetate