کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4425618 | 1309109 | 2011 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha](/preview/png/4425618.png)
Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the non-target organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 μg L−1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 μg L−1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.
Research highlights
► Bioaccumulation of levonorgestrel in mussels is higher than expected based on its lipophilicity.
► Exposure to levonorgestrel causes oxidative stress and enhanced elimination processes.
► Glutathione S-transferase (pi class) mRNA induction after one day hint on phase II biotransformation.
► mRNA induction of heat shock protein 70 after one week prove protein damage.
Journal: Environmental Pollution - Volume 159, Issue 1, January 2011, Pages 38–44