Phytosterols Act as Endocrine and Metabolic Disruptors in the European Polecat (Mustela putorius)

Department of Biology, University of Joensuu, Joensuu, Finland.
Toxicology and Applied Pharmacology (Impact Factor: 3.71). 02/2002; 178(1):22-8. DOI: 10.1006/taap.2001.9315
Source: PubMed


Phytosterols or plant sterols (PS) are consumed as natural remedies and margarines by the general population in developed countries to lower elevated serum cholesterol levels. They are also present in high concentrations in pulp mill effluents. The aim of the study was to screen the endocrine and metabolic parameters of the European polecat (Mustela putorius) for the effects of PS. The results showed an increase in the plasma estradiol and TH levels with no effects on the hypophyseal regulatory hormones. The plasma ghrelin levels decreased. PS also affected intermediary metabolism. The liver glycogen content increased as did the kidney glucose-6-phosphatase activity. The liver lipase esterase activity, on the other hand, decreased due to PS. In serum lipids the total cholesterol did not change, but the low-density lipoprotein levels increased and the high-density lipoprotein-cholesterol ratio decreased. PS had widespread previously unreported effects on the physiology of the polecat. The multiple effects indicate the need of a thorough risk assessment of the effects and interactions of PS.

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