Effects of Selected Metal Oxide Nanoparticles on Multiple Biomarkers in Carassius auratus

Objective To study the biological effects of nanoscale copper oxide （nCuO）, zinc oxide （nZnO）, cerium dioxide （nCeO2） and their mixtures on Carassius auratus. Methods Juvenile fish （Carossius auratus） were exposed to aqueous suspensions of nCuO, nZnO, and nCeO2 （alone and in mixtures） at concentrations of 20, 40, 80, 3.60, and 320 mg/L. The biomarkers-acetylcholinesterase （ACHE） in brain, sodium/potassium-activated ATPase （Na~/K＊-ATPase） in gill, and superoxide dismutase （SOD） and catalase （CAT） in liver-were determined after 4 days of exposure. Integrated biomarker response （IBR） was calculated by combining multiple biomarkers into a single value. Results AChE and SOD activities were significantly inhibited by all test metal oxide nanoparticles （NPs） at high concentrations （__.160 rag/L） with the exception of nCeO2. Na~/K＋-ATPase induction exhibited bell-shaped concentration-response curves. CAT activity was significantly inhibited at concentrations equal to or higher than 160 mg/L. The order of IBR values was nCeO2 = nZnO/nCeO2= nCuO/nCeO2 〈 nCuO/nZnO/nCeO2 〈 nZnO 〈 nCuO 〈 nCuO/nZnO. The joint effect seemed to be synergistic for nCuO/nZnO mixtures, additive for the ternary mixture and less than additive or antagonistic for the binary mixtures containing nCe02. Conclusion Concentration-dependent changes of enzymatic activities （ACHE, Na~/K＊-ATPase, SOD, and CAT） were observed in fish exposed to nanoscale metal oxides. IBR analysis allowed good discrimination between the different exposures and might be a useful tool for the quantification of integrated negative effects induced by NPs toward fish.

Single and Combined Effects of Estrone and 17 β-Estradiol on Male Goldfish

Objective To assess the single and combined effects of estrone （El） and 1713-estradiol （E2） on goldfish （ Carassius auratus）. Methods Batch tests were conducted. Serum levels of vitellogenin （VTG） and E2, gonadosomatic indices （GSI）, gonadal DNA damage and liver 7-ethoxyresorufin-O-deethylase （EROD） activity were measured after exposure for 14 days. Results The VTG level increased significantly in a concentration-dependent manner. The serum E2 level was significantly higher and the GSI level was significantly lower in goldfish after exposed to the 3 drugs. DNA damage occurred in treated samples and EROD activity was significantly suppressed 7 days after exposure. The joint effect of E1 and E2 was additive with regard to VTG induction. Conclusion The results of our study highlight a series of effects of steroidal estrogens on goldfish. Further study is needed to confirm their effect as a whole.