Expression of Vitamin D Receptor by Pulse Consumption in the Uterus of Menopausal Mouse Model

Abstract

Objectives: Phytoestrogen-containing pulse supplements have beneficial effects on postmenopausal symptoms, but how such effects are achieved is unclear. This study investigates the effects of pulse consumption on the menopausal changes in ovariectomized rats. Methods: Female Sprague-Dawley rats were either sham operated (Sham; n = 3) or surgically ovariectomized (n = 13). The Sham group was fed the regular AIN-93M diet. Ovariectomized group was divided into 3 sub-groups and fed AIN-93M containing soybean (n = 5), mung bean (n = 3), or cowpea (n = 5) for 10 weeks. At the end of the experiment, all rats were sacrificed, and the uterus was harvested, rinsed, and weighed. Expressions of vitamin D receptor (VDR), estrogen receptor (ER) β, and ezrin in uterus were evaluated by immunohistochemistry. Results: VDR was highly expressed in the uterus of rat, irrespective of ovariectomized state. VDR was more definitely expressed in the uterus of ovariectomized groups than the sham-operated group. There were no significant differences in expression of ER β. However the expression of ezrin was highly expressed in the cowpea group compared to sham group (P = 0.044). Conclusion: This study suggested that legumes diet may concern menopausal changes via VDR and ezrin. The result may partly explain the beneficial effects of VDR on menopausal symptoms. Further study is necessary to study the detailed mechanisms of VDR and ezrin on the menopausal changes in the uterus. (J Korean Soc Menopause 2013;19:1-8)