Haben Lignane im Weizen- und Leinsamenbrot eine östrogenartige Wirkung auf Uterus und Mamma bei der ovarektomierten Ratte im Vergleich mit 17-β-Östradiol?
Do lignans in wheat- and flaxseed bread have an estrogen-like effect on uterus and mammary gland of the ovariectomized rat compared to 17-β-estradiol?
von Jens Kölbel
Datum der mündl. Prüfung:2015-11-10
Betreuer:Prof. Dr. Wolfgang Wuttke
Gutachter:PD Dr. Michael Müller
Gutachter:Prof. Dr. Martin Oppermann
EnglischAn increasing contamination of our environment with estrogen-like acting substances and a growing number of reports about negative health effects of endocrine disruptors in human and wildlife lead to one question: is our food polluted with harmful substances? Studies have shown that wheat and flaxseed are contaminated with estrogen-like acting substances and both are often used in the preparation of our staple food bread. Especially flaxseed contains significant amounts of different phytoestrogens and of the metalloestrogen cadmium. Estrogens have a stimulating effect on the uterine tissue and the mammary gland of ovariectomized rats, who are an established model for testing estrogen-like acting substances, as they are a hormonal equivalent to the postmenopausal woman. The present paper consequently examines, if the consumption of the whole food item wheat bread resp. flaxseed bread has an estrogenic effect on the uterine tissue and the mammary gland of the ovariectomized rat. Therefore 43 Sprague- Dawley rats were ovariectomized and then fed estrogen-free chow (negative control-group), estrogen-containing chow (positive control-group), wheat bread and flaxseed bread. After a trial-period of two months the rats were sacrificed and the following data was collected: uterine weight, uterine layer thickness and the mammary gland morphology. While the positive control-group showed a significant stimulation of the uterine tissue and the mammary gland, no effect was seen in the wheat bread- and the flaxseed bread group. Hence we can conclude that the endocrine-like acting substances contained in wheat and flaxseed seem to have no significant effect on the examined organs when fed as a whole food item like bread. This suggests that the consumption of wheat bread and flaxseed bread has no harmful effects on human health.
Keywords: estrogen; uterus; mammary gland; phytoestrogens