J Vet Sci.  2011 Jun;12(2):121-126. 10.4142/jvs.2011.12.2.121.

Evaluation of the estrogenic effects of dietary perinatal Trifolium pratense

• Yatkin E
• Daglioglu

• KMID: 1106553
• DOI: http://doi.org/10.4142/jvs.2011.12.2.121

Abstract

This study was designed to investigate the potential estrogenic effects of perinatal dietary phytoestrogens on the rat uterus. Pregnant rats were divided to three groups provided the following diets: (1) rat chow, (2) rat chow with 7.5% Trifolium (T.) pratense, or (3) rat chow supplemented with 17beta-estradiol (0.5 mg/kg). The dams in each group were kept on the same diet during pregnancy and lactation. Female offspring were euthanized on day 21 at which time body and organ weights were recorded and tissue samples were taken for histology. Immunohistochemistry was performed to detect estrogen receptor alpha (ERalpha) and progesterone receptor (PR) levels. Our results revealed estrogen-like biological effects of perinatal T. pratense exposure. Relative uterus and ovary weights in the experimental groups were increased compared to control. The number of uterine glands and luminal epithelium heights were also increased. However, there were no statistically significant changes detected in the immunostaining intensity of ERalpha and PR between the groups.

Keyword

estrogen receptor alpha; progesterone receptor; rat uterus; red clover; Trifolium pratense

MeSH Terms

Animals
Animals, Suckling
Body Weight/drug effects
Estrogen Receptor alpha/*metabolism
Female
Immunohistochemistry
Isoflavones/*pharmacology
Lactation
Maternal Exposure
Organ Size/drug effects
Phytoestrogens/*pharmacology
Plant Components, Aerial/chemistry
Pregnancy
Rats
Rats, Wistar
Receptors, Progesterone/*metabolism
Trifolium/*chemistry
Uterus/*drug effects

Figure

• 

  Fig. 1 Immunohistochemical expression of estrogen receptor alpha (ERα) in the uterus and progesterone receptor (PR) in the uterus and uterine tube. M: myometrium, GE: glandular epithelium, E: endometrium, LE: luminal epithelium, L: lumen. Arrows: nuclear staining of ERα and PR. Counterstain with Mayer's hematoxylin. Scale bars = 50 µm.

• 

  Fig. 2 ERα (A) and PR (B) immunostaining score in the uterus of 21-day-old rats. The proportion of positively stained cells was scored as follows: 0, none; 1, weak; 2, moderate; 3, strong; 4, intense staining.

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