Publication Abstract

Effects of 17α-ethynylestradiol on EROD activity, spiggin and vitellogenin in three-spined stickleback (Gasterosteus aculeatus)

Effects of 17α-ethynylestradiol on EROD activity, spiggin and vitellogenin in three-spined stickleback (Gasterosteus aculeatus)

C. Andersson, I. Katsiadaki, K. Lundstedt-Enkel and J. Örberg

The three-spined stickleback (Gasterosteus aculeatus) has quantifiable biomarkers of exposure to estrogens (vitellogenin), androgens (spiggin) and arylhydrocarbon receptor (AhR) agonists (EROD activity) and is therefore a promising test species for biomonitoring of reprotoxic chemicals in aquatic environments. In this study we evaluated the effects of 17α-ethynylestradiol (EE₂) on EROD activity, induction of vitellogenin and spiggin, hepatosomatic index (HSI), ovarian somatic index (OSI) and nephrosomatic index (NSI). Adult male and female three-spined sticklebacks were exposed to concentrations of 0- 170 ng EE₂/l (measured concentrations) in a flow-through system for 21 days. Exposure to 170 ng EE₂/l resulted in an 8- and 9-fold induction of EROD activity in males and females, respectively. In livers, EROD activity expressed in relation to microsomal protein content was suppressed due to a significant increase in microsomal protein content. Hepatic EROD activity per se expressed as picomol/min was not affected by exposure to EE₂. The lowest observed effect concentration for induction of vitellogenin in males was 53.7 ng EE₂/l. In females, vitellogenin levels were significantly higher in those exposed to170 ng EE₂/l compared to controls. Spiggin production was inhibited and NSI lower in males exposed to 170 ng EE₂/l. In both females and males LSI was higher in fish exposed to 170 ng EE₂/l than in controls. In females, OSI was significantly lower and NSI was higher than controls. The observed results from this study shows that a synthetic estrogen can affect the well-known biomarker of exposure for dioxin-like compounds, EROD activity, and further that this response can differ between tissues; in this case between gills and liver. In addition, exposure to EE₂ affected both induction of vitellogenin and spiggin.

Reference

C. Andersson, I. Katsiadaki, K. Lundstedt-Enkel and J. Örberg (2007) Effects of 17α-ethynylestradiol on EROD activity, spiggin and vitellogenin in three-spined stickleback (Gasterosteus aculeatus). Aquatic Toxicology, 83(1): 33.42

C. Andersson, I. Katsiadaki*, K. Lundstedt-Enkel and J. Örberg

Aquatic Toxicology, 83(1): 33-42